ntp_proto.c revision 309007
154359Sroberto/* 254359Sroberto * ntp_proto.c - NTP version 4 protocol machinery 354363Sroberto * 4132454Sroberto * ATTENTION: Get approval from Dave Mills on all changes to this file! 5132454Sroberto * 654359Sroberto */ 754359Sroberto#ifdef HAVE_CONFIG_H 854359Sroberto#include <config.h> 954359Sroberto#endif 1054359Sroberto 1154359Sroberto#include "ntpd.h" 1254359Sroberto#include "ntp_stdlib.h" 1354359Sroberto#include "ntp_unixtime.h" 1454359Sroberto#include "ntp_control.h" 1554359Sroberto#include "ntp_string.h" 16280849Scy#include "ntp_leapsec.h" 17285169Scy#include "refidsmear.h" 18293423Sdelphij#include "lib_strbuf.h" 1954359Sroberto 2082505Sroberto#include <stdio.h> 21280849Scy#ifdef HAVE_LIBSCF_H 22280849Scy#include <libscf.h> 2354359Sroberto#endif 24280849Scy#ifdef HAVE_UNISTD_H 25280849Scy#include <unistd.h> 2654359Sroberto#endif 2754359Sroberto 28298695Sdelphij/* [Bug 3031] define automatic broadcastdelay cutoff preset */ 29298695Sdelphij#ifndef BDELAY_DEFAULT 30298695Sdelphij# define BDELAY_DEFAULT (-0.050) 31298695Sdelphij#endif 32298695Sdelphij 3354359Sroberto/* 34182007Sroberto * This macro defines the authentication state. If x is 1 authentication 35182007Sroberto * is required; othewise it is optional. 36182007Sroberto */ 37289764Sglebius#define AUTH(x, y) ((x) ? (y) == AUTH_OK \ 38289764Sglebius : (y) == AUTH_OK || (y) == AUTH_NONE) 39182007Sroberto 40280849Scy#define AUTH_NONE 0 /* authentication not required */ 41280849Scy#define AUTH_OK 1 /* authentication OK */ 42280849Scy#define AUTH_ERROR 2 /* authentication error */ 43280849Scy#define AUTH_CRYPTO 3 /* crypto_NAK */ 44280849Scy 45182007Sroberto/* 46289764Sglebius * Set up Kiss Code values 47289764Sglebius */ 48289764Sglebius 49289764Sglebiusenum kiss_codes { 50289764Sglebius NOKISS, /* No Kiss Code */ 51289764Sglebius RATEKISS, /* Rate limit Kiss Code */ 52289764Sglebius DENYKISS, /* Deny Kiss */ 53289764Sglebius RSTRKISS, /* Restricted Kiss */ 54289764Sglebius XKISS, /* Experimental Kiss */ 55289764Sglebius UNKNOWNKISS /* Unknown Kiss Code */ 56289764Sglebius}; 57289764Sglebius 58298695Sdelphijenum nak_error_codes { 59298695Sdelphij NONAK, /* No NAK seen */ 60298695Sdelphij INVALIDNAK, /* NAK cannot be used */ 61298695Sdelphij VALIDNAK /* NAK is valid */ 62298695Sdelphij}; 63298695Sdelphij 64289764Sglebius/* 65280849Scy * traffic shaping parameters 6654359Sroberto */ 67280849Scy#define NTP_IBURST 6 /* packets in iburst */ 68280849Scy#define RESP_DELAY 1 /* refclock burst delay (s) */ 69280849Scy 70280849Scy/* 71280849Scy * pool soliciting restriction duration (s) 72280849Scy */ 73280849Scy#define POOL_SOLICIT_WINDOW 8 74280849Scy 75280849Scy/* 76280849Scy * peer_select groups statistics for a peer used by clock_select() and 77280849Scy * clock_cluster(). 78280849Scy */ 79280849Scytypedef struct peer_select_tag { 80280849Scy struct peer * peer; 81280849Scy double synch; /* sync distance */ 82280849Scy double error; /* jitter */ 83280849Scy double seljit; /* selection jitter */ 84280849Scy} peer_select; 85280849Scy 86280849Scy/* 87280849Scy * System variables are declared here. Unless specified otherwise, all 88280849Scy * times are in seconds. 89280849Scy */ 90285169Scyu_char sys_leap; /* system leap indicator, use set_sys_leap() to change this */ 91285169Scyu_char xmt_leap; /* leap indicator sent in client requests, set up by set_sys_leap() */ 92280849Scyu_char sys_stratum; /* system stratum */ 93182007Srobertos_char sys_precision; /* local clock precision (log2 s) */ 9482505Srobertodouble sys_rootdelay; /* roundtrip delay to primary source */ 95280849Scydouble sys_rootdisp; /* dispersion to primary source */ 96280849Scyu_int32 sys_refid; /* reference id (network byte order) */ 97280849Scyl_fp sys_reftime; /* last update time */ 98280849Scystruct peer *sys_peer; /* current peer */ 9954359Sroberto 100285169Scy#ifdef LEAP_SMEAR 101285169Scystruct leap_smear_info leap_smear; 102285169Scy#endif 103285169Scyint leap_sec_in_progress; 104285169Scy 10554359Sroberto/* 106280849Scy * Rate controls. Leaky buckets are used to throttle the packet 107280849Scy * transmission rates in order to protect busy servers such as at NIST 108280849Scy * and USNO. There is a counter for each association and another for KoD 109280849Scy * packets. The association counter decrements each second, but not 110280849Scy * below zero. Each time a packet is sent the counter is incremented by 111280849Scy * a configurable value representing the average interval between 112280849Scy * packets. A packet is delayed as long as the counter is greater than 113280849Scy * zero. Note this does not affect the time value computations. 11454359Sroberto */ 115280849Scy/* 116280849Scy * Nonspecified system state variables 117280849Scy */ 118132454Srobertoint sys_bclient; /* broadcast client enable */ 119132454Srobertodouble sys_bdelay; /* broadcast client default delay */ 12054359Srobertoint sys_authenticate; /* requre authentication for config */ 12154359Srobertol_fp sys_authdelay; /* authentication delay */ 122280849Scydouble sys_offset; /* current local clock offset */ 123280849Scydouble sys_mindisp = MINDISPERSE; /* minimum distance (s) */ 124280849Scydouble sys_maxdist = MAXDISTANCE; /* selection threshold */ 125280849Scydouble sys_jitter; /* system jitter */ 126280849Scyu_long sys_epoch; /* last clock update time */ 127280849Scystatic double sys_clockhop; /* clockhop threshold */ 128280849Scystatic int leap_vote_ins; /* leap consensus for insert */ 129280849Scystatic int leap_vote_del; /* leap consensus for delete */ 13082505Srobertokeyid_t sys_private; /* private value for session seed */ 13182505Srobertoint sys_manycastserver; /* respond to manycast client pkts */ 132280849Scyint ntp_mode7; /* respond to ntpdc (mode7) */ 13382505Srobertoint peer_ntpdate; /* active peers in ntpdate mode */ 134132454Srobertoint sys_survivors; /* truest of the truechimers */ 135280849Scychar *sys_ident = NULL; /* identity scheme */ 13654359Sroberto 13754359Sroberto/* 138132454Sroberto * TOS and multicast mapping stuff 139132454Sroberto */ 140182007Srobertoint sys_floor = 0; /* cluster stratum floor */ 141309007Sdelphiju_char sys_bcpollbstep = 0; /* Broadcast Poll backstep gate */ 142280849Scyint sys_ceiling = STRATUM_UNSPEC - 1; /* cluster stratum ceiling */ 143132454Srobertoint sys_minsane = 1; /* minimum candidates */ 144280849Scyint sys_minclock = NTP_MINCLOCK; /* minimum candidates */ 145182007Srobertoint sys_maxclock = NTP_MAXCLOCK; /* maximum candidates */ 146132454Srobertoint sys_cohort = 0; /* cohort switch */ 147182007Srobertoint sys_orphan = STRATUM_UNSPEC + 1; /* orphan stratum */ 148280849Scyint sys_orphwait = NTP_ORPHWAIT; /* orphan wait */ 149182007Srobertoint sys_beacon = BEACON; /* manycast beacon interval */ 150132454Srobertoint sys_ttlmax; /* max ttl mapping vector index */ 151132454Srobertou_char sys_ttl[MAX_TTL]; /* ttl mapping vector */ 152132454Sroberto 153132454Sroberto/* 154280849Scy * Statistics counters - first the good, then the bad 15554359Sroberto */ 156280849Scyu_long sys_stattime; /* elapsed time */ 157132454Srobertou_long sys_received; /* packets received */ 158280849Scyu_long sys_processed; /* packets for this host */ 159280849Scyu_long sys_newversion; /* current version */ 160280849Scyu_long sys_oldversion; /* old version */ 161132454Srobertou_long sys_restricted; /* access denied */ 162132454Srobertou_long sys_badlength; /* bad length or format */ 163132454Srobertou_long sys_badauth; /* bad authentication */ 164280849Scyu_long sys_declined; /* declined */ 165132454Srobertou_long sys_limitrejected; /* rate exceeded */ 166280849Scyu_long sys_kodsent; /* KoD sent */ 16754359Sroberto 168294554Sdelphij/* 169301247Sdelphij * Mechanism knobs: how soon do we peer_clear() or unpeer()? 170294554Sdelphij * 171294554Sdelphij * The default way is "on-receipt". If this was a packet from a 172294554Sdelphij * well-behaved source, on-receipt will offer the fastest recovery. 173294554Sdelphij * If this was from a DoS attack, the default way makes it easier 174294554Sdelphij * for a bad-guy to DoS us. So look and see what bites you harder 175294554Sdelphij * and choose according to your environment. 176294554Sdelphij */ 177301247Sdelphijint peer_clear_digest_early = 1; /* bad digest (TEST5) and Autokey */ 178294554Sdelphijint unpeer_crypto_early = 1; /* bad crypto (TEST9) */ 179294554Sdelphijint unpeer_crypto_nak_early = 1; /* crypto_NAK (TEST5) */ 180294554Sdelphijint unpeer_digest_early = 1; /* bad digest (TEST5) */ 181294554Sdelphij 182298695Sdelphijint dynamic_interleave = DYNAMIC_INTERLEAVE; /* Bug 2978 mitigation */ 183298695Sdelphij 184298695Sdelphijint kiss_code_check(u_char hisleap, u_char hisstratum, u_char hismode, u_int32 refid); 185298695Sdelphijenum nak_error_codes valid_NAK(struct peer *peer, struct recvbuf *rbufp, u_char hismode); 186280849Scystatic double root_distance (struct peer *); 187280849Scystatic void clock_combine (peer_select *, int, int); 188280849Scystatic void peer_xmit (struct peer *); 189280849Scystatic void fast_xmit (struct recvbuf *, int, keyid_t, int); 190280849Scystatic void pool_xmit (struct peer *); 191280849Scystatic void clock_update (struct peer *); 192280849Scystatic void measure_precision(void); 193280849Scystatic double measure_tick_fuzz(void); 194280849Scystatic int local_refid (struct peer *); 195280849Scystatic int peer_unfit (struct peer *); 196280849Scy#ifdef AUTOKEY 197280849Scystatic int group_test (char *, char *); 198280849Scy#endif /* AUTOKEY */ 199280849Scy#ifdef WORKER 200280849Scyvoid pool_name_resolved (int, int, void *, const char *, 201280849Scy const char *, const struct addrinfo *, 202280849Scy const struct addrinfo *); 203280849Scy#endif /* WORKER */ 20454359Sroberto 205293423Sdelphijconst char * amtoa (int am); 206293423Sdelphij 207293423Sdelphij 208285169Scyvoid 209293423Sdelphijset_sys_leap( 210293423Sdelphij u_char new_sys_leap 211293423Sdelphij ) 212293423Sdelphij{ 213285169Scy sys_leap = new_sys_leap; 214285169Scy xmt_leap = sys_leap; 215182007Sroberto 216285169Scy /* 217285169Scy * Under certain conditions we send faked leap bits to clients, so 218285169Scy * eventually change xmt_leap below, but never change LEAP_NOTINSYNC. 219285169Scy */ 220285169Scy if (xmt_leap != LEAP_NOTINSYNC) { 221285169Scy if (leap_sec_in_progress) { 222285169Scy /* always send "not sync" */ 223285169Scy xmt_leap = LEAP_NOTINSYNC; 224285169Scy } 225285169Scy#ifdef LEAP_SMEAR 226285169Scy else { 227285169Scy /* 228293423Sdelphij * If leap smear is enabled in general we must 229293423Sdelphij * never send a leap second warning to clients, 230293423Sdelphij * so make sure we only send "in sync". 231285169Scy */ 232285169Scy if (leap_smear.enabled) 233285169Scy xmt_leap = LEAP_NOWARNING; 234285169Scy } 235285169Scy#endif /* LEAP_SMEAR */ 236285169Scy } 237285169Scy} 238285169Scy 239293423Sdelphij 240289764Sglebius/* 241289764Sglebius * Kiss Code check 242289764Sglebius */ 243293423Sdelphijint 244293423Sdelphijkiss_code_check( 245293423Sdelphij u_char hisleap, 246293423Sdelphij u_char hisstratum, 247293423Sdelphij u_char hismode, 248293423Sdelphij u_int32 refid 249293423Sdelphij ) 250293423Sdelphij{ 251285169Scy 252293423Sdelphij if ( hismode == MODE_SERVER 253293423Sdelphij && hisleap == LEAP_NOTINSYNC 254293423Sdelphij && hisstratum == STRATUM_UNSPEC) { 255293423Sdelphij if(memcmp(&refid,"RATE", 4) == 0) { 256293423Sdelphij return (RATEKISS); 257293423Sdelphij } else if(memcmp(&refid,"DENY", 4) == 0) { 258293423Sdelphij return (DENYKISS); 259293423Sdelphij } else if(memcmp(&refid,"RSTR", 4) == 0) { 260293423Sdelphij return (RSTRKISS); 261293423Sdelphij } else if(memcmp(&refid,"X", 1) == 0) { 262293423Sdelphij return (XKISS); 263293423Sdelphij } else { 264293423Sdelphij return (UNKNOWNKISS); 265289764Sglebius } 266293423Sdelphij } else { 267293423Sdelphij return (NOKISS); 268293423Sdelphij } 269289764Sglebius} 270293423Sdelphij 271293423Sdelphij 272298695Sdelphij/* 273298695Sdelphij * Check that NAK is valid 274298695Sdelphij */ 275298695Sdelphijenum nak_error_codes 276298695Sdelphijvalid_NAK( 277298695Sdelphij struct peer *peer, 278298695Sdelphij struct recvbuf *rbufp, 279298695Sdelphij u_char hismode 280298695Sdelphij ) 281298695Sdelphij{ 282309007Sdelphij int base_packet_length = MIN_V4_PKT_LEN; 283301247Sdelphij int remainder_size; 284301247Sdelphij struct pkt * rpkt; 285301247Sdelphij int keyid; 286301247Sdelphij l_fp p_org; /* origin timestamp */ 287301247Sdelphij const l_fp * myorg; /* selected peer origin */ 288298695Sdelphij 289298695Sdelphij /* 290298695Sdelphij * Check to see if there is something beyond the basic packet 291298695Sdelphij */ 292298695Sdelphij if (rbufp->recv_length == base_packet_length) { 293298695Sdelphij return NONAK; 294298695Sdelphij } 295298695Sdelphij 296298695Sdelphij remainder_size = rbufp->recv_length - base_packet_length; 297298695Sdelphij /* 298298695Sdelphij * Is this a potential NAK? 299298695Sdelphij */ 300298695Sdelphij if (remainder_size != 4) { 301298695Sdelphij return NONAK; 302298695Sdelphij } 303298695Sdelphij 304298695Sdelphij /* 305298695Sdelphij * Only server responses can contain NAK's 306298695Sdelphij */ 307298695Sdelphij 308298695Sdelphij if (hismode != MODE_SERVER && 309298695Sdelphij hismode != MODE_ACTIVE && 310298695Sdelphij hismode != MODE_PASSIVE 311298695Sdelphij ) { 312301247Sdelphij return INVALIDNAK; 313298695Sdelphij } 314298695Sdelphij 315298695Sdelphij /* 316298695Sdelphij * Make sure that the extra field in the packet is all zeros 317298695Sdelphij */ 318298695Sdelphij rpkt = &rbufp->recv_pkt; 319298695Sdelphij keyid = ntohl(((u_int32 *)rpkt)[base_packet_length / 4]); 320298695Sdelphij if (keyid != 0) { 321301247Sdelphij return INVALIDNAK; 322298695Sdelphij } 323298695Sdelphij 324298695Sdelphij /* 325298695Sdelphij * Only valid if peer uses a key 326298695Sdelphij */ 327301247Sdelphij if (!peer || !peer->keyid || !(peer->flags & FLAG_SKEY)) { 328301247Sdelphij return INVALIDNAK; 329298695Sdelphij } 330301247Sdelphij 331301247Sdelphij /* 332301247Sdelphij * The ORIGIN must match, or this cannot be a valid NAK, either. 333301247Sdelphij */ 334301247Sdelphij NTOHL_FP(&rpkt->org, &p_org); 335301247Sdelphij if (peer->flip > 0) 336301247Sdelphij myorg = &peer->borg; 337301247Sdelphij else 338301247Sdelphij myorg = &peer->aorg; 339309007Sdelphij 340301247Sdelphij if (L_ISZERO(&p_org) || 341301247Sdelphij L_ISZERO( myorg) || 342301247Sdelphij !L_ISEQU(&p_org, myorg)) { 343301247Sdelphij return INVALIDNAK; 344298695Sdelphij } 345301247Sdelphij 346301247Sdelphij /* If we ever passed all that checks, we should be safe. Well, 347301247Sdelphij * as safe as we can ever be with an unauthenticated crypto-nak. 348301247Sdelphij */ 349301247Sdelphij return VALIDNAK; 350298695Sdelphij} 351298695Sdelphij 352298695Sdelphij 35354359Sroberto/* 354280849Scy * transmit - transmit procedure called by poll timeout 35554359Sroberto */ 35654359Srobertovoid 35754359Srobertotransmit( 35854359Sroberto struct peer *peer /* peer structure pointer */ 35954359Sroberto ) 36054359Sroberto{ 361280849Scy u_char hpoll; 36254359Sroberto 363132454Sroberto /* 364132454Sroberto * The polling state machine. There are two kinds of machines, 365132454Sroberto * those that never expect a reply (broadcast and manycast 366132454Sroberto * server modes) and those that do (all other modes). The dance 367132454Sroberto * is intricate... 368132454Sroberto */ 36954359Sroberto hpoll = peer->hpoll; 370182007Sroberto 371182007Sroberto /* 372182007Sroberto * In broadcast mode the poll interval is never changed from 373182007Sroberto * minpoll. 374182007Sroberto */ 375132454Sroberto if (peer->cast_flags & (MDF_BCAST | MDF_MCAST)) { 376182007Sroberto peer->outdate = current_time; 377280849Scy if (sys_leap != LEAP_NOTINSYNC) 378280849Scy peer_xmit(peer); 379182007Sroberto poll_update(peer, hpoll); 380182007Sroberto return; 381182007Sroberto } 38254359Sroberto 383182007Sroberto /* 384182007Sroberto * In manycast mode we start with unity ttl. The ttl is 385182007Sroberto * increased by one for each poll until either sys_maxclock 386182007Sroberto * servers have been found or the maximum ttl is reached. When 387182007Sroberto * sys_maxclock servers are found we stop polling until one or 388280849Scy * more servers have timed out or until less than sys_minclock 389182007Sroberto * associations turn up. In this case additional better servers 390280849Scy * are dragged in and preempt the existing ones. Once every 391280849Scy * sys_beacon seconds we are to transmit unconditionally, but 392280849Scy * this code is not quite right -- peer->unreach counts polls 393280849Scy * and is being compared with sys_beacon, so the beacons happen 394280849Scy * every sys_beacon polls. 395182007Sroberto */ 396182007Sroberto if (peer->cast_flags & MDF_ACAST) { 397182007Sroberto peer->outdate = current_time; 398182007Sroberto if (peer->unreach > sys_beacon) { 399182007Sroberto peer->unreach = 0; 400182007Sroberto peer->ttl = 0; 401182007Sroberto peer_xmit(peer); 402289764Sglebius } else if ( sys_survivors < sys_minclock 403289764Sglebius || peer_associations < sys_maxclock) { 404280849Scy if (peer->ttl < (u_int32)sys_ttlmax) 405182007Sroberto peer->ttl++; 406182007Sroberto peer_xmit(peer); 407182007Sroberto } 408182007Sroberto peer->unreach++; 409182007Sroberto poll_update(peer, hpoll); 410182007Sroberto return; 411182007Sroberto } 41282505Sroberto 413182007Sroberto /* 414280849Scy * Pool associations transmit unicast solicitations when there 415280849Scy * are less than a hard limit of 2 * sys_maxclock associations, 416280849Scy * and either less than sys_minclock survivors or less than 417280849Scy * sys_maxclock associations. The hard limit prevents unbounded 418280849Scy * growth in associations if the system clock or network quality 419280849Scy * result in survivor count dipping below sys_minclock often. 420280849Scy * This was observed testing with pool, where sys_maxclock == 12 421280849Scy * resulted in 60 associations without the hard limit. A 422280849Scy * similar hard limit on manycastclient ephemeral associations 423280849Scy * may be appropriate. 424280849Scy */ 425280849Scy if (peer->cast_flags & MDF_POOL) { 426280849Scy peer->outdate = current_time; 427289764Sglebius if ( (peer_associations <= 2 * sys_maxclock) 428289764Sglebius && ( peer_associations < sys_maxclock 429293423Sdelphij || sys_survivors < sys_minclock)) 430280849Scy pool_xmit(peer); 431280849Scy poll_update(peer, hpoll); 432280849Scy return; 433280849Scy } 434280849Scy 435280849Scy /* 436182007Sroberto * In unicast modes the dance is much more intricate. It is 437280849Scy * designed to back off whenever possible to minimize network 438182007Sroberto * traffic. 439182007Sroberto */ 440182007Sroberto if (peer->burst == 0) { 441182007Sroberto u_char oreach; 442182007Sroberto 443132454Sroberto /* 444182007Sroberto * Update the reachability status. If not heard for 445182007Sroberto * three consecutive polls, stuff infinity in the clock 446282408Scy * filter. 447132454Sroberto */ 448182007Sroberto oreach = peer->reach; 449182007Sroberto peer->outdate = current_time; 450280849Scy peer->unreach++; 451182007Sroberto peer->reach <<= 1; 452182007Sroberto if (!peer->reach) { 45382505Sroberto 454182007Sroberto /* 455182007Sroberto * Here the peer is unreachable. If it was 456280849Scy * previously reachable raise a trap. Send a 457280849Scy * burst if enabled. 458182007Sroberto */ 459280849Scy clock_filter(peer, 0., 0., MAXDISPERSE); 460182007Sroberto if (oreach) { 461280849Scy peer_unfit(peer); 462280849Scy report_event(PEVNT_UNREACH, peer, NULL); 463182007Sroberto } 464289764Sglebius if ( (peer->flags & FLAG_IBURST) 465289764Sglebius && peer->retry == 0) 466280849Scy peer->retry = NTP_RETRY; 467182007Sroberto } else { 468182007Sroberto 469182007Sroberto /* 470280849Scy * Here the peer is reachable. Send a burst if 471280849Scy * enabled and the peer is fit. Reset unreach 472280849Scy * for persistent and ephemeral associations. 473280849Scy * Unreach is also reset for survivors in 474280849Scy * clock_select(). 475182007Sroberto */ 476280849Scy hpoll = sys_poll; 477280849Scy if (!(peer->flags & FLAG_PREEMPT)) 478182007Sroberto peer->unreach = 0; 479289764Sglebius if ( (peer->flags & FLAG_BURST) 480289764Sglebius && peer->retry == 0 481289764Sglebius && !peer_unfit(peer)) 482280849Scy peer->retry = NTP_RETRY; 483182007Sroberto } 484182007Sroberto 485132454Sroberto /* 486280849Scy * Watch for timeout. If ephemeral, toss the rascal; 487280849Scy * otherwise, bump the poll interval. Note the 488280849Scy * poll_update() routine will clamp it to maxpoll. 489280849Scy * If preemptible and we have more peers than maxclock, 490280849Scy * and this peer has the minimum score of preemptibles, 491280849Scy * demobilize. 492282408Scy */ 493132454Sroberto if (peer->unreach >= NTP_UNREACH) { 494280849Scy hpoll++; 495280849Scy /* ephemeral: no FLAG_CONFIG nor FLAG_PREEMPT */ 496280849Scy if (!(peer->flags & (FLAG_CONFIG | FLAG_PREEMPT))) { 497280849Scy report_event(PEVNT_RESTART, peer, "timeout"); 498182007Sroberto peer_clear(peer, "TIME"); 49982505Sroberto unpeer(peer); 50082505Sroberto return; 50182505Sroberto } 502289764Sglebius if ( (peer->flags & FLAG_PREEMPT) 503289764Sglebius && (peer_associations > sys_maxclock) 504289764Sglebius && score_all(peer)) { 505280849Scy report_event(PEVNT_RESTART, peer, "timeout"); 506280849Scy peer_clear(peer, "TIME"); 507280849Scy unpeer(peer); 508280849Scy return; 509280849Scy } 51082505Sroberto } 511182007Sroberto } else { 512182007Sroberto peer->burst--; 513132454Sroberto if (peer->burst == 0) { 51454359Sroberto 51554359Sroberto /* 516182007Sroberto * If ntpdate mode and the clock has not been 517182007Sroberto * set and all peers have completed the burst, 518182007Sroberto * we declare a successful failure. 51954359Sroberto */ 520182007Sroberto if (mode_ntpdate) { 521182007Sroberto peer_ntpdate--; 522182007Sroberto if (peer_ntpdate == 0) { 523132454Sroberto msyslog(LOG_NOTICE, 524280849Scy "ntpd: no servers found"); 525280849Scy if (!msyslog_term) 526280849Scy printf( 527280849Scy "ntpd: no servers found\n"); 528132454Sroberto exit (0); 529132454Sroberto } 53054359Sroberto } 53154359Sroberto } 53254359Sroberto } 533280849Scy if (peer->retry > 0) 534280849Scy peer->retry--; 53554359Sroberto 53654359Sroberto /* 537282408Scy * Do not transmit if in broadcast client mode. 53854359Sroberto */ 539182007Sroberto if (peer->hmode != MODE_BCLIENT) 540182007Sroberto peer_xmit(peer); 541132454Sroberto poll_update(peer, hpoll); 542293423Sdelphij 543293423Sdelphij return; 54454359Sroberto} 54554359Sroberto 546182007Sroberto 547293423Sdelphijconst char * 548293423Sdelphijamtoa( 549293423Sdelphij int am 550293423Sdelphij ) 551293423Sdelphij{ 552293423Sdelphij char *bp; 553293423Sdelphij 554293423Sdelphij switch(am) { 555293423Sdelphij case AM_ERR: return "AM_ERR"; 556293423Sdelphij case AM_NOMATCH: return "AM_NOMATCH"; 557293423Sdelphij case AM_PROCPKT: return "AM_PROCPKT"; 558293423Sdelphij case AM_BCST: return "AM_BCST"; 559293423Sdelphij case AM_FXMIT: return "AM_FXMIT"; 560293423Sdelphij case AM_MANYCAST: return "AM_MANYCAST"; 561293423Sdelphij case AM_NEWPASS: return "AM_NEWPASS"; 562293423Sdelphij case AM_NEWBCL: return "AM_NEWBCL"; 563293423Sdelphij case AM_POSSBCL: return "AM_POSSBCL"; 564293423Sdelphij default: 565293423Sdelphij LIB_GETBUF(bp); 566293423Sdelphij snprintf(bp, LIB_BUFLENGTH, "AM_#%d", am); 567293423Sdelphij return bp; 568293423Sdelphij } 569293423Sdelphij} 570293423Sdelphij 571293423Sdelphij 57254359Sroberto/* 573280849Scy * receive - receive procedure called for each packet received 57454359Sroberto */ 57554359Srobertovoid 57654359Srobertoreceive( 57754359Sroberto struct recvbuf *rbufp 57854359Sroberto ) 57954359Sroberto{ 580132454Sroberto register struct peer *peer; /* peer structure pointer */ 581132454Sroberto register struct pkt *pkt; /* receive packet pointer */ 582280849Scy u_char hisversion; /* packet version */ 583280849Scy u_char hisleap; /* packet leap indicator */ 584280849Scy u_char hismode; /* packet mode */ 585280849Scy u_char hisstratum; /* packet stratum */ 586280849Scy u_short restrict_mask; /* restrict bits */ 587293423Sdelphij const char *hm_str; /* hismode string */ 588293423Sdelphij const char *am_str; /* association match string */ 589293423Sdelphij int kissCode = NOKISS; /* Kiss Code */ 590132454Sroberto int has_mac; /* length of MAC field */ 591132454Sroberto int authlen; /* offset of MAC field */ 592301247Sdelphij int is_authentic = AUTH_NONE; /* cryptosum ok */ 593298695Sdelphij int crypto_nak_test; /* result of crypto-NAK check */ 594280849Scy int retcode = AM_NOMATCH; /* match code */ 595280849Scy keyid_t skeyid = 0; /* key IDs */ 596280849Scy u_int32 opcode = 0; /* extension field opcode */ 597293423Sdelphij sockaddr_u *dstadr_sin; /* active runway */ 598132454Sroberto struct peer *peer2; /* aux peer structure pointer */ 599293423Sdelphij endpt *match_ep; /* newpeer() local address */ 600182007Sroberto l_fp p_org; /* origin timestamp */ 601182007Sroberto l_fp p_rec; /* receive timestamp */ 602132454Sroberto l_fp p_xmt; /* transmit timestamp */ 603280849Scy#ifdef AUTOKEY 604280849Scy char hostname[NTP_MAXSTRLEN + 1]; 605280849Scy char *groupname = NULL; 606132454Sroberto struct autokey *ap; /* autokey structure pointer */ 607132454Sroberto int rval; /* cookie snatcher */ 608280849Scy keyid_t pkeyid = 0, tkeyid = 0; /* key IDs */ 609280849Scy#endif /* AUTOKEY */ 610280849Scy#ifdef HAVE_NTP_SIGND 611280849Scy static unsigned char zero_key[16]; 612280849Scy#endif /* HAVE_NTP_SIGND */ 61354359Sroberto 61454359Sroberto /* 61582505Sroberto * Monitor the packet and get restrictions. Note that the packet 61682505Sroberto * length for control and private mode packets must be checked 617280849Scy * by the service routines. Some restrictions have to be handled 618280849Scy * later in order to generate a kiss-o'-death packet. 61954359Sroberto */ 620132454Sroberto /* 621132454Sroberto * Bogus port check is before anything, since it probably 622132454Sroberto * reveals a clogging attack. 623132454Sroberto */ 624132454Sroberto sys_received++; 625280849Scy if (0 == SRCPORT(&rbufp->recv_srcadr)) { 626132454Sroberto sys_badlength++; 627132454Sroberto return; /* bogus port */ 628132454Sroberto } 629280849Scy restrict_mask = restrictions(&rbufp->recv_srcadr); 630293423Sdelphij pkt = &rbufp->recv_pkt; 631293423Sdelphij DPRINTF(2, ("receive: at %ld %s<-%s flags %x restrict %03x org %#010x.%08x xmt %#010x.%08x\n", 632132454Sroberto current_time, stoa(&rbufp->dstadr->sin), 633293423Sdelphij stoa(&rbufp->recv_srcadr), rbufp->dstadr->flags, 634293423Sdelphij restrict_mask, ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf), 635293423Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf))); 636182007Sroberto hisversion = PKT_VERSION(pkt->li_vn_mode); 637182007Sroberto hisleap = PKT_LEAP(pkt->li_vn_mode); 638132454Sroberto hismode = (int)PKT_MODE(pkt->li_vn_mode); 639182007Sroberto hisstratum = PKT_TO_STRATUM(pkt->stratum); 640301247Sdelphij INSIST(0 != hisstratum); 641301247Sdelphij 642280849Scy if (restrict_mask & RES_IGNORE) { 643280849Scy sys_restricted++; 644280849Scy return; /* ignore everything */ 645280849Scy } 646132454Sroberto if (hismode == MODE_PRIVATE) { 647280849Scy if (!ntp_mode7 || (restrict_mask & RES_NOQUERY)) { 648132454Sroberto sys_restricted++; 64982505Sroberto return; /* no query private */ 650132454Sroberto } 65156749Sroberto process_private(rbufp, ((restrict_mask & 65256749Sroberto RES_NOMODIFY) == 0)); 65354359Sroberto return; 65454359Sroberto } 655132454Sroberto if (hismode == MODE_CONTROL) { 656132454Sroberto if (restrict_mask & RES_NOQUERY) { 657132454Sroberto sys_restricted++; 65882505Sroberto return; /* no query control */ 659132454Sroberto } 66054359Sroberto process_control(rbufp, restrict_mask); 66154359Sroberto return; 66254359Sroberto } 663132454Sroberto if (restrict_mask & RES_DONTSERVE) { 664132454Sroberto sys_restricted++; 665280849Scy return; /* no time serve */ 666132454Sroberto } 667280849Scy 668280849Scy /* 669280849Scy * This is for testing. If restricted drop ten percent of 670280849Scy * surviving packets. 671280849Scy */ 672280849Scy if (restrict_mask & RES_FLAKE) { 673280849Scy if ((double)ntp_random() / 0x7fffffff < .1) { 674280849Scy sys_restricted++; 675280849Scy return; /* no flakeway */ 676280849Scy } 67782505Sroberto } 678282408Scy 679132454Sroberto /* 680132454Sroberto * Version check must be after the query packets, since they 681280849Scy * intentionally use an early version. 682132454Sroberto */ 683182007Sroberto if (hisversion == NTP_VERSION) { 684280849Scy sys_newversion++; /* new version */ 685289764Sglebius } else if ( !(restrict_mask & RES_VERSION) 686289764Sglebius && hisversion >= NTP_OLDVERSION) { 687280849Scy sys_oldversion++; /* previous version */ 688132454Sroberto } else { 689280849Scy sys_badlength++; 690132454Sroberto return; /* old version */ 691132454Sroberto } 69254359Sroberto 69354359Sroberto /* 694132454Sroberto * Figure out his mode and validate the packet. This has some 695132454Sroberto * legacy raunch that probably should be removed. In very early 696132454Sroberto * NTP versions mode 0 was equivalent to what later versions 697132454Sroberto * would interpret as client mode. 69854359Sroberto */ 69982505Sroberto if (hismode == MODE_UNSPEC) { 700182007Sroberto if (hisversion == NTP_OLDVERSION) { 701132454Sroberto hismode = MODE_CLIENT; 702132454Sroberto } else { 703132454Sroberto sys_badlength++; 704132454Sroberto return; /* invalid mode */ 705132454Sroberto } 70682505Sroberto } 70754359Sroberto 70854359Sroberto /* 70982505Sroberto * Parse the extension field if present. We figure out whether 71082505Sroberto * an extension field is present by measuring the MAC size. If 711182007Sroberto * the number of words following the packet header is 0, no MAC 712182007Sroberto * is present and the packet is not authenticated. If 1, the 713182007Sroberto * packet is a crypto-NAK; if 3, the packet is authenticated 714280849Scy * with DES; if 5, the packet is authenticated with MD5; if 6, 715280849Scy * the packet is authenticated with SHA. If 2 or * 4, the packet 716280849Scy * is a runt and discarded forthwith. If greater than 6, an 717280849Scy * extension field is present, so we subtract the length of the 718280849Scy * field and go around again. 71954359Sroberto */ 720298695Sdelphij 72154359Sroberto authlen = LEN_PKT_NOMAC; 722132454Sroberto has_mac = rbufp->recv_length - authlen; 723132454Sroberto while (has_mac > 0) { 724280849Scy u_int32 len; 725280849Scy#ifdef AUTOKEY 726280849Scy u_int32 hostlen; 727280849Scy struct exten *ep; 728280849Scy#endif /*AUTOKEY */ 72982505Sroberto 730280849Scy if (has_mac % 4 != 0 || has_mac < (int)MIN_MAC_LEN) { 73154359Sroberto sys_badlength++; 732280849Scy return; /* bad length */ 73354359Sroberto } 734280849Scy if (has_mac <= (int)MAX_MAC_LEN) { 73582505Sroberto skeyid = ntohl(((u_int32 *)pkt)[authlen / 4]); 73682505Sroberto break; 73754359Sroberto 738280849Scy } else { 739280849Scy opcode = ntohl(((u_int32 *)pkt)[authlen / 4]); 740280849Scy len = opcode & 0xffff; 741289764Sglebius if ( len % 4 != 0 742289764Sglebius || len < 4 743289764Sglebius || (int)len + authlen > rbufp->recv_length) { 74482505Sroberto sys_badlength++; 745280849Scy return; /* bad length */ 74682505Sroberto } 747280849Scy#ifdef AUTOKEY 748280849Scy /* 749280849Scy * Extract calling group name for later. If 750280849Scy * sys_groupname is non-NULL, there must be 751280849Scy * a group name provided to elicit a response. 752280849Scy */ 753289764Sglebius if ( (opcode & 0x3fff0000) == CRYPTO_ASSOC 754289764Sglebius && sys_groupname != NULL) { 755280849Scy ep = (struct exten *)&((u_int32 *)pkt)[authlen / 4]; 756280849Scy hostlen = ntohl(ep->vallen); 757289764Sglebius if ( hostlen >= sizeof(hostname) 758289764Sglebius || hostlen > len - 759289764Sglebius offsetof(struct exten, pkt)) { 760280849Scy sys_badlength++; 761280849Scy return; /* bad length */ 762280849Scy } 763280849Scy memcpy(hostname, &ep->pkt, hostlen); 764280849Scy hostname[hostlen] = '\0'; 765280849Scy groupname = strchr(hostname, '@'); 766280849Scy if (groupname == NULL) { 767280849Scy sys_declined++; 768280849Scy return; 769280849Scy } 770280849Scy groupname++; 771280849Scy } 772280849Scy#endif /* AUTOKEY */ 773280849Scy authlen += len; 774280849Scy has_mac -= len; 77582505Sroberto } 77654359Sroberto } 77754359Sroberto 77854359Sroberto /* 779280849Scy * If has_mac is < 0 we had a malformed packet. 780280849Scy */ 781280849Scy if (has_mac < 0) { 782280849Scy sys_badlength++; 783280849Scy return; /* bad length */ 784280849Scy } 785280849Scy 786280849Scy /* 787280849Scy * If authentication required, a MAC must be present. 788280849Scy */ 789280849Scy if (restrict_mask & RES_DONTTRUST && has_mac == 0) { 790280849Scy sys_restricted++; 791280849Scy return; /* access denied */ 792280849Scy } 793280849Scy 794280849Scy /* 795280849Scy * Update the MRU list and finger the cloggers. It can be a 796280849Scy * little expensive, so turn it off for production use. 797280849Scy * RES_LIMITED and RES_KOD will be cleared in the returned 798280849Scy * restrict_mask unless one or both actions are warranted. 799280849Scy */ 800280849Scy restrict_mask = ntp_monitor(rbufp, restrict_mask); 801280849Scy if (restrict_mask & RES_LIMITED) { 802280849Scy sys_limitrejected++; 803289764Sglebius if ( !(restrict_mask & RES_KOD) 804289764Sglebius || MODE_BROADCAST == hismode 805289764Sglebius || MODE_SERVER == hismode) { 806280849Scy if (MODE_SERVER == hismode) 807280849Scy DPRINTF(1, ("Possibly self-induced rate limiting of MODE_SERVER from %s\n", 808280849Scy stoa(&rbufp->recv_srcadr))); 809280849Scy return; /* rate exceeded */ 810280849Scy } 811280849Scy if (hismode == MODE_CLIENT) 812280849Scy fast_xmit(rbufp, MODE_SERVER, skeyid, 813280849Scy restrict_mask); 814280849Scy else 815280849Scy fast_xmit(rbufp, MODE_ACTIVE, skeyid, 816280849Scy restrict_mask); 817280849Scy return; /* rate exceeded */ 818280849Scy } 819280849Scy restrict_mask &= ~RES_KOD; 820280849Scy 821280849Scy /* 82282505Sroberto * We have tossed out as many buggy packets as possible early in 82382505Sroberto * the game to reduce the exposure to a clogging attack. Now we 82482505Sroberto * have to burn some cycles to find the association and 82582505Sroberto * authenticate the packet if required. Note that we burn only 826280849Scy * digest cycles, again to reduce exposure. There may be no 82782505Sroberto * matching association and that's okay. 82882505Sroberto * 82982505Sroberto * More on the autokey mambo. Normally the local interface is 83082505Sroberto * found when the association was mobilized with respect to a 83182505Sroberto * designated remote address. We assume packets arriving from 83282505Sroberto * the remote address arrive via this interface and the local 83382505Sroberto * address used to construct the autokey is the unicast address 83482505Sroberto * of the interface. However, if the sender is a broadcaster, 83582505Sroberto * the interface broadcast address is used instead. 836280849Scy * Notwithstanding this technobabble, if the sender is a 83782505Sroberto * multicaster, the broadcast address is null, so we use the 83882505Sroberto * unicast address anyway. Don't ask. 83954359Sroberto */ 840280849Scy peer = findpeer(rbufp, hismode, &retcode); 84182505Sroberto dstadr_sin = &rbufp->dstadr->sin; 842182007Sroberto NTOHL_FP(&pkt->org, &p_org); 843182007Sroberto NTOHL_FP(&pkt->rec, &p_rec); 844182007Sroberto NTOHL_FP(&pkt->xmt, &p_xmt); 845293423Sdelphij hm_str = modetoa(hismode); 846293423Sdelphij am_str = amtoa(retcode); 847182007Sroberto 848182007Sroberto /* 849182007Sroberto * Authentication is conditioned by three switches: 850182007Sroberto * 851182007Sroberto * NOPEER (RES_NOPEER) do not mobilize an association unless 852182007Sroberto * authenticated 853182007Sroberto * NOTRUST (RES_DONTTRUST) do not allow access unless 854182007Sroberto * authenticated (implies NOPEER) 855182007Sroberto * enable (sys_authenticate) master NOPEER switch, by default 856182007Sroberto * on 857182007Sroberto * 858182007Sroberto * The NOPEER and NOTRUST can be specified on a per-client basis 859182007Sroberto * using the restrict command. The enable switch if on implies 860182007Sroberto * NOPEER for all clients. There are four outcomes: 861182007Sroberto * 862182007Sroberto * NONE The packet has no MAC. 863182007Sroberto * OK the packet has a MAC and authentication succeeds 864182007Sroberto * ERROR the packet has a MAC and authentication fails 865182007Sroberto * CRYPTO crypto-NAK. The MAC has four octets only. 866182007Sroberto * 867182007Sroberto * Note: The AUTH(x, y) macro is used to filter outcomes. If x 868182007Sroberto * is zero, acceptable outcomes of y are NONE and OK. If x is 869182007Sroberto * one, the only acceptable outcome of y is OK. 870182007Sroberto */ 871298695Sdelphij crypto_nak_test = valid_NAK(peer, rbufp, hismode); 872280849Scy 873298695Sdelphij /* 874298695Sdelphij * Drop any invalid crypto-NAKs 875298695Sdelphij */ 876298695Sdelphij if (crypto_nak_test == INVALIDNAK) { 877298695Sdelphij report_event(PEVNT_AUTH, peer, "Invalid_NAK"); 878298695Sdelphij if (0 != peer) { 879298695Sdelphij peer->badNAK++; 880298695Sdelphij } 881298695Sdelphij msyslog(LOG_ERR, "Invalid-NAK error at %ld %s<-%s", 882298695Sdelphij current_time, stoa(dstadr_sin), stoa(&rbufp->recv_srcadr)); 883298695Sdelphij return; 884298695Sdelphij } 885298695Sdelphij 88654359Sroberto if (has_mac == 0) { 887280849Scy restrict_mask &= ~RES_MSSNTP; 888182007Sroberto is_authentic = AUTH_NONE; /* not required */ 889293423Sdelphij DPRINTF(2, ("receive: at %ld %s<-%s mode %d/%s:%s len %d org %#010x.%08x xmt %#010x.%08x NOMAC\n", 890182007Sroberto current_time, stoa(dstadr_sin), 891293423Sdelphij stoa(&rbufp->recv_srcadr), hismode, hm_str, am_str, 892293423Sdelphij authlen, 893293423Sdelphij ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf), 894293423Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf))); 895298695Sdelphij } else if (crypto_nak_test == VALIDNAK) { 896280849Scy restrict_mask &= ~RES_MSSNTP; 897280849Scy is_authentic = AUTH_CRYPTO; /* crypto-NAK */ 898293423Sdelphij DPRINTF(2, ("receive: at %ld %s<-%s mode %d/%s:%s keyid %08x len %d auth %d org %#010x.%08x xmt %#010x.%08x MAC4\n", 899182007Sroberto current_time, stoa(dstadr_sin), 900293423Sdelphij stoa(&rbufp->recv_srcadr), hismode, hm_str, am_str, 901293423Sdelphij skeyid, authlen + has_mac, is_authentic, 902293423Sdelphij ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf), 903293423Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf))); 904280849Scy 905280849Scy#ifdef HAVE_NTP_SIGND 906280849Scy /* 907280849Scy * If the signature is 20 bytes long, the last 16 of 908280849Scy * which are zero, then this is a Microsoft client 909280849Scy * wanting AD-style authentication of the server's 910282408Scy * reply. 911280849Scy * 912280849Scy * This is described in Microsoft's WSPP docs, in MS-SNTP: 913280849Scy * http://msdn.microsoft.com/en-us/library/cc212930.aspx 914280849Scy */ 915289764Sglebius } else if ( has_mac == MAX_MD5_LEN 916289764Sglebius && (restrict_mask & RES_MSSNTP) 917289764Sglebius && (retcode == AM_FXMIT || retcode == AM_NEWPASS) 918289764Sglebius && (memcmp(zero_key, (char *)pkt + authlen + 4, 919293423Sdelphij MAX_MD5_LEN - 4) == 0)) { 920280849Scy is_authentic = AUTH_NONE; 921280849Scy#endif /* HAVE_NTP_SIGND */ 922280849Scy 92354359Sroberto } else { 924280849Scy restrict_mask &= ~RES_MSSNTP; 925280849Scy#ifdef AUTOKEY 92682505Sroberto /* 92782505Sroberto * For autokey modes, generate the session key 92882505Sroberto * and install in the key cache. Use the socket 92982505Sroberto * broadcast or unicast address as appropriate. 93082505Sroberto */ 931280849Scy if (crypto_flags && skeyid > NTP_MAXKEY) { 932282408Scy 93382505Sroberto /* 93482505Sroberto * More on the autokey dance (AKD). A cookie is 93582505Sroberto * constructed from public and private values. 93682505Sroberto * For broadcast packets, the cookie is public 93782505Sroberto * (zero). For packets that match no 93882505Sroberto * association, the cookie is hashed from the 93982505Sroberto * addresses and private value. For server 94082505Sroberto * packets, the cookie was previously obtained 94182505Sroberto * from the server. For symmetric modes, the 94282505Sroberto * cookie was previously constructed using an 94382505Sroberto * agreement protocol; however, should PKI be 94482505Sroberto * unavailable, we construct a fake agreement as 94582505Sroberto * the EXOR of the peer and host cookies. 94682505Sroberto * 94782505Sroberto * hismode ephemeral persistent 94882505Sroberto * ======================================= 94982505Sroberto * active 0 cookie# 95082505Sroberto * passive 0% cookie# 95182505Sroberto * client sys cookie 0% 95282505Sroberto * server 0% sys cookie 95382505Sroberto * broadcast 0 0 95482505Sroberto * 95582505Sroberto * # if unsync, 0 95682505Sroberto * % can't happen 95782505Sroberto */ 958280849Scy if (has_mac < (int)MAX_MD5_LEN) { 959280849Scy sys_badauth++; 960280849Scy return; 961280849Scy } 96282505Sroberto if (hismode == MODE_BROADCAST) { 96354359Sroberto 96482505Sroberto /* 96582505Sroberto * For broadcaster, use the interface 96682505Sroberto * broadcast address when available; 96782505Sroberto * otherwise, use the unicast address 96882505Sroberto * found when the association was 969182007Sroberto * mobilized. However, if this is from 970182007Sroberto * the wildcard interface, game over. 97182505Sroberto */ 972289764Sglebius if ( crypto_flags 973289764Sglebius && rbufp->dstadr == 974289764Sglebius ANY_INTERFACE_CHOOSE(&rbufp->recv_srcadr)) { 975182007Sroberto sys_restricted++; 976182007Sroberto return; /* no wildcard */ 977182007Sroberto } 97882505Sroberto pkeyid = 0; 979280849Scy if (!SOCK_UNSPEC(&rbufp->dstadr->bcast)) 98082505Sroberto dstadr_sin = 98182505Sroberto &rbufp->dstadr->bcast; 98282505Sroberto } else if (peer == NULL) { 98382505Sroberto pkeyid = session_key( 98482505Sroberto &rbufp->recv_srcadr, dstadr_sin, 0, 98582505Sroberto sys_private, 0); 98682505Sroberto } else { 987132454Sroberto pkeyid = peer->pcookie; 98882505Sroberto } 98982505Sroberto 99054359Sroberto /* 99182505Sroberto * The session key includes both the public 99282505Sroberto * values and cookie. In case of an extension 99382505Sroberto * field, the cookie used for authentication 99482505Sroberto * purposes is zero. Note the hash is saved for 99582505Sroberto * use later in the autokey mambo. 99654359Sroberto */ 997280849Scy if (authlen > (int)LEN_PKT_NOMAC && pkeyid != 0) { 99882505Sroberto session_key(&rbufp->recv_srcadr, 99982505Sroberto dstadr_sin, skeyid, 0, 2); 100054359Sroberto tkeyid = session_key( 100182505Sroberto &rbufp->recv_srcadr, dstadr_sin, 100282505Sroberto skeyid, pkeyid, 0); 100382505Sroberto } else { 100454359Sroberto tkeyid = session_key( 100582505Sroberto &rbufp->recv_srcadr, dstadr_sin, 100682505Sroberto skeyid, pkeyid, 2); 100754359Sroberto } 100854359Sroberto 100954359Sroberto } 1010280849Scy#endif /* AUTOKEY */ 101154359Sroberto 101254359Sroberto /* 101354359Sroberto * Compute the cryptosum. Note a clogging attack may 101482505Sroberto * succeed in bloating the key cache. If an autokey, 101582505Sroberto * purge it immediately, since we won't be needing it 1016182007Sroberto * again. If the packet is authentic, it can mobilize an 1017182007Sroberto * association. Note that there is no key zero. 101854359Sroberto */ 1019182007Sroberto if (!authdecrypt(skeyid, (u_int32 *)pkt, authlen, 1020280849Scy has_mac)) 1021182007Sroberto is_authentic = AUTH_ERROR; 1022280849Scy else 1023182007Sroberto is_authentic = AUTH_OK; 1024280849Scy#ifdef AUTOKEY 1025280849Scy if (crypto_flags && skeyid > NTP_MAXKEY) 102682505Sroberto authtrust(skeyid, 0); 1027280849Scy#endif /* AUTOKEY */ 1028293423Sdelphij DPRINTF(2, ("receive: at %ld %s<-%s mode %d/%s:%s keyid %08x len %d auth %d org %#010x.%08x xmt %#010x.%08x\n", 1029132454Sroberto current_time, stoa(dstadr_sin), 1030293423Sdelphij stoa(&rbufp->recv_srcadr), hismode, hm_str, am_str, 1031293423Sdelphij skeyid, authlen + has_mac, is_authentic, 1032293423Sdelphij ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf), 1033293423Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf))); 103454359Sroberto } 103554359Sroberto 103654359Sroberto /* 103782505Sroberto * The association matching rules are implemented by a set of 1038182007Sroberto * routines and an association table. A packet matching an 1039182007Sroberto * association is processed by the peer process for that 1040182007Sroberto * association. If there are no errors, an ephemeral association 1041182007Sroberto * is mobilized: a broadcast packet mobilizes a broadcast client 1042132454Sroberto * aassociation; a manycast server packet mobilizes a manycast 1043132454Sroberto * client association; a symmetric active packet mobilizes a 1044182007Sroberto * symmetric passive association. 104554359Sroberto */ 104654359Sroberto switch (retcode) { 1047182007Sroberto 1048182007Sroberto /* 1049182007Sroberto * This is a client mode packet not matching any association. If 1050182007Sroberto * an ordinary client, simply toss a server mode packet back 1051182007Sroberto * over the fence. If a manycast client, we have to work a 1052182007Sroberto * little harder. 1053182007Sroberto */ 105454359Sroberto case AM_FXMIT: 105554359Sroberto 105656749Sroberto /* 1057280849Scy * If authentication OK, send a server reply; otherwise, 1058280849Scy * send a crypto-NAK. 105956749Sroberto */ 1060182007Sroberto if (!(rbufp->dstadr->flags & INT_MCASTOPEN)) { 1061182007Sroberto if (AUTH(restrict_mask & RES_DONTTRUST, 1062280849Scy is_authentic)) { 1063182007Sroberto fast_xmit(rbufp, MODE_SERVER, skeyid, 1064182007Sroberto restrict_mask); 1065280849Scy } else if (is_authentic == AUTH_ERROR) { 1066182007Sroberto fast_xmit(rbufp, MODE_SERVER, 0, 1067182007Sroberto restrict_mask); 1068280849Scy sys_badauth++; 1069280849Scy } else { 1070280849Scy sys_restricted++; 1071280849Scy } 1072182007Sroberto return; /* hooray */ 107356749Sroberto } 107454359Sroberto 107556749Sroberto /* 1076182007Sroberto * This must be manycast. Do not respond if not 1077182007Sroberto * configured as a manycast server. 107856749Sroberto */ 1079182007Sroberto if (!sys_manycastserver) { 1080182007Sroberto sys_restricted++; 1081182007Sroberto return; /* not enabled */ 1082182007Sroberto } 1083182007Sroberto 1084280849Scy#ifdef AUTOKEY 1085182007Sroberto /* 1086280849Scy * Do not respond if not the same group. 1087182007Sroberto */ 1088280849Scy if (group_test(groupname, NULL)) { 1089280849Scy sys_declined++; 1090280849Scy return; 1091280849Scy } 1092280849Scy#endif /* AUTOKEY */ 1093182007Sroberto 1094182007Sroberto /* 1095280849Scy * Do not respond if we are not synchronized or our 1096280849Scy * stratum is greater than the manycaster or the 1097280849Scy * manycaster has already synchronized to us. 1098182007Sroberto */ 1099289764Sglebius if ( sys_leap == LEAP_NOTINSYNC 1100289764Sglebius || sys_stratum >= hisstratum 1101289764Sglebius || (!sys_cohort && sys_stratum == hisstratum + 1) 1102289764Sglebius || rbufp->dstadr->addr_refid == pkt->refid) { 1103280849Scy sys_declined++; 1104182007Sroberto return; /* no help */ 1105280849Scy } 1106182007Sroberto 1107182007Sroberto /* 1108182007Sroberto * Respond only if authentication succeeds. Don't do a 1109182007Sroberto * crypto-NAK, as that would not be useful. 1110182007Sroberto */ 1111182007Sroberto if (AUTH(restrict_mask & RES_DONTTRUST, is_authentic)) 111282505Sroberto fast_xmit(rbufp, MODE_SERVER, skeyid, 111382505Sroberto restrict_mask); 1114182007Sroberto return; /* hooray */ 1115182007Sroberto 1116182007Sroberto /* 1117182007Sroberto * This is a server mode packet returned in response to a client 1118280849Scy * mode packet sent to a multicast group address (for 1119280849Scy * manycastclient) or to a unicast address (for pool). The 1120280849Scy * origin timestamp is a good nonce to reliably associate the 1121280849Scy * reply with what was sent. If there is no match, that's 1122280849Scy * curious and could be an intruder attempting to clog, so we 1123280849Scy * just ignore it. 1124182007Sroberto * 1125282408Scy * If the packet is authentic and the manycastclient or pool 1126280849Scy * association is found, we mobilize a client association and 1127280849Scy * copy pertinent variables from the manycastclient or pool 1128280849Scy * association to the new client association. If not, just 1129280849Scy * ignore the packet. 1130182007Sroberto * 1131182007Sroberto * There is an implosion hazard at the manycast client, since 1132182007Sroberto * the manycast servers send the server packet immediately. If 1133182007Sroberto * the guy is already here, don't fire up a duplicate. 1134182007Sroberto */ 113554359Sroberto case AM_MANYCAST: 113654359Sroberto 1137280849Scy#ifdef AUTOKEY 1138280849Scy /* 1139280849Scy * Do not respond if not the same group. 1140280849Scy */ 1141280849Scy if (group_test(groupname, NULL)) { 1142280849Scy sys_declined++; 1143280849Scy return; 1144280849Scy } 1145280849Scy#endif /* AUTOKEY */ 1146182007Sroberto if ((peer2 = findmanycastpeer(rbufp)) == NULL) { 1147132454Sroberto sys_restricted++; 1148182007Sroberto return; /* not enabled */ 1149132454Sroberto } 1150289764Sglebius if (!AUTH( (!(peer2->cast_flags & MDF_POOL) 1151289764Sglebius && sys_authenticate) 1152289764Sglebius || (restrict_mask & (RES_NOPEER | 1153289764Sglebius RES_DONTTRUST)), is_authentic)) { 1154280849Scy sys_restricted++; 1155280849Scy return; /* access denied */ 1156280849Scy } 1157132454Sroberto 1158132454Sroberto /* 1159280849Scy * Do not respond if unsynchronized or stratum is below 1160280849Scy * the floor or at or above the ceiling. 1161132454Sroberto */ 1162289764Sglebius if ( hisleap == LEAP_NOTINSYNC 1163289764Sglebius || hisstratum < sys_floor 1164289764Sglebius || hisstratum >= sys_ceiling) { 1165280849Scy sys_declined++; 1166280849Scy return; /* no help */ 1167280849Scy } 1168280849Scy peer = newpeer(&rbufp->recv_srcadr, NULL, rbufp->dstadr, 1169280849Scy MODE_CLIENT, hisversion, peer2->minpoll, 1170280849Scy peer2->maxpoll, FLAG_PREEMPT | 1171280849Scy (FLAG_IBURST & peer2->flags), MDF_UCAST | 1172280849Scy MDF_UCLNT, 0, skeyid, sys_ident); 1173280849Scy if (NULL == peer) { 1174280849Scy sys_declined++; 1175280849Scy return; /* ignore duplicate */ 1176280849Scy } 117756749Sroberto 1178280849Scy /* 1179280849Scy * After each ephemeral pool association is spun, 1180280849Scy * accelerate the next poll for the pool solicitor so 1181280849Scy * the pool will fill promptly. 1182280849Scy */ 1183280849Scy if (peer2->cast_flags & MDF_POOL) 1184280849Scy peer2->nextdate = current_time + 1; 1185280849Scy 1186280849Scy /* 1187280849Scy * Further processing of the solicitation response would 1188280849Scy * simply detect its origin timestamp as bogus for the 1189280849Scy * brand-new association (it matches the prototype 1190280849Scy * association) and tinker with peer->nextdate delaying 1191280849Scy * first sync. 1192280849Scy */ 1193280849Scy return; /* solicitation response handled */ 1194280849Scy 1195182007Sroberto /* 1196182007Sroberto * This is the first packet received from a broadcast server. If 1197182007Sroberto * the packet is authentic and we are enabled as broadcast 1198182007Sroberto * client, mobilize a broadcast client association. We don't 1199182007Sroberto * kiss any frogs here. 1200182007Sroberto */ 1201182007Sroberto case AM_NEWBCL: 1202280849Scy 1203280849Scy#ifdef AUTOKEY 1204280849Scy /* 1205280849Scy * Do not respond if not the same group. 1206280849Scy */ 1207280849Scy if (group_test(groupname, sys_ident)) { 1208280849Scy sys_declined++; 1209280849Scy return; 1210280849Scy } 1211280849Scy#endif /* AUTOKEY */ 1212280849Scy if (sys_bclient == 0) { 1213280849Scy sys_restricted++; 1214280849Scy return; /* not enabled */ 1215280849Scy } 1216182007Sroberto if (!AUTH(sys_authenticate | (restrict_mask & 1217280849Scy (RES_NOPEER | RES_DONTTRUST)), is_authentic)) { 1218280849Scy sys_restricted++; 1219280849Scy return; /* access denied */ 1220280849Scy } 122154359Sroberto 122256749Sroberto /* 1223182007Sroberto * Do not respond if unsynchronized or stratum is below 1224182007Sroberto * the floor or at or above the ceiling. 122556749Sroberto */ 1226289764Sglebius if ( hisleap == LEAP_NOTINSYNC 1227289764Sglebius || hisstratum < sys_floor 1228289764Sglebius || hisstratum >= sys_ceiling) { 1229280849Scy sys_declined++; 1230280849Scy return; /* no help */ 1231280849Scy } 1232132454Sroberto 1233280849Scy#ifdef AUTOKEY 123456749Sroberto /* 1235280849Scy * Do not respond if Autokey and the opcode is not a 1236280849Scy * CRYPTO_ASSOC response with association ID. 123756749Sroberto */ 1238289764Sglebius if ( crypto_flags && skeyid > NTP_MAXKEY 1239289764Sglebius && (opcode & 0xffff0000) != (CRYPTO_ASSOC | CRYPTO_RESP)) { 1240280849Scy sys_declined++; 1241280849Scy return; /* protocol error */ 1242280849Scy } 1243280849Scy#endif /* AUTOKEY */ 124482505Sroberto 1245132454Sroberto /* 1246280849Scy * Broadcasts received via a multicast address may 1247280849Scy * arrive after a unicast volley has begun 1248280849Scy * with the same remote address. newpeer() will not 1249280849Scy * find duplicate associations on other local endpoints 1250280849Scy * if a non-NULL endpoint is supplied. multicastclient 1251280849Scy * ephemeral associations are unique across all local 1252280849Scy * endpoints. 1253132454Sroberto */ 1254280849Scy if (!(INT_MCASTOPEN & rbufp->dstadr->flags)) 1255280849Scy match_ep = rbufp->dstadr; 1256280849Scy else 1257280849Scy match_ep = NULL; 125856749Sroberto 1259132454Sroberto /* 1260280849Scy * Determine whether to execute the initial volley. 126156749Sroberto */ 1262298695Sdelphij if (sys_bdelay > 0.0) { 1263280849Scy#ifdef AUTOKEY 1264182007Sroberto /* 1265182007Sroberto * If a two-way exchange is not possible, 1266182007Sroberto * neither is Autokey. 1267182007Sroberto */ 1268280849Scy if (crypto_flags && skeyid > NTP_MAXKEY) { 1269280849Scy sys_restricted++; 1270182007Sroberto return; /* no autokey */ 1271182007Sroberto } 1272280849Scy#endif /* AUTOKEY */ 1273280849Scy 1274280849Scy /* 1275280849Scy * Do not execute the volley. Start out in 1276280849Scy * broadcast client mode. 1277280849Scy */ 1278280849Scy peer = newpeer(&rbufp->recv_srcadr, NULL, 1279280849Scy match_ep, MODE_BCLIENT, hisversion, 1280280849Scy pkt->ppoll, pkt->ppoll, FLAG_PREEMPT, 1281280849Scy MDF_BCLNT, 0, skeyid, sys_ident); 1282280849Scy if (NULL == peer) { 1283280849Scy sys_restricted++; 1284280849Scy return; /* ignore duplicate */ 1285280849Scy 1286280849Scy } else { 1287280849Scy peer->delay = sys_bdelay; 1288294554Sdelphij peer->bxmt = p_xmt; 1289280849Scy } 1290280849Scy break; 1291132454Sroberto } 129256749Sroberto 1293280849Scy /* 1294280849Scy * Execute the initial volley in order to calibrate the 1295280849Scy * propagation delay and run the Autokey protocol. 1296280849Scy * 1297280849Scy * Note that the minpoll is taken from the broadcast 1298280849Scy * packet, normally 6 (64 s) and that the poll interval 1299280849Scy * is fixed at this value. 1300280849Scy */ 1301280849Scy peer = newpeer(&rbufp->recv_srcadr, NULL, match_ep, 1302280849Scy MODE_CLIENT, hisversion, pkt->ppoll, pkt->ppoll, 1303280849Scy FLAG_BC_VOL | FLAG_IBURST | FLAG_PREEMPT, MDF_BCLNT, 1304280849Scy 0, skeyid, sys_ident); 1305280849Scy if (NULL == peer) { 1306280849Scy sys_restricted++; 1307280849Scy return; /* ignore duplicate */ 1308280849Scy } 1309294554Sdelphij peer->bxmt = p_xmt; 1310280849Scy#ifdef AUTOKEY 1311280849Scy if (skeyid > NTP_MAXKEY) 1312280849Scy crypto_recv(peer, rbufp); 1313280849Scy#endif /* AUTOKEY */ 1314280849Scy 1315280849Scy return; /* hooray */ 1316280849Scy 1317182007Sroberto /* 1318182007Sroberto * This is the first packet received from a symmetric active 1319182007Sroberto * peer. If the packet is authentic and the first he sent, 1320182007Sroberto * mobilize a passive association. If not, kiss the frog. 1321182007Sroberto */ 1322182007Sroberto case AM_NEWPASS: 132356749Sroberto 1324280849Scy#ifdef AUTOKEY 132556749Sroberto /* 1326280849Scy * Do not respond if not the same group. 132756749Sroberto */ 1328280849Scy if (group_test(groupname, sys_ident)) { 1329280849Scy sys_declined++; 1330280849Scy return; 1331280849Scy } 1332280849Scy#endif /* AUTOKEY */ 1333280849Scy if (!AUTH(sys_authenticate | (restrict_mask & 1334280849Scy (RES_NOPEER | RES_DONTTRUST)), is_authentic)) { 1335280849Scy 1336280849Scy /* 1337280849Scy * If authenticated but cannot mobilize an 1338280849Scy * association, send a symmetric passive 1339280849Scy * response without mobilizing an association. 1340280849Scy * This is for drat broken Windows clients. See 1341280849Scy * Microsoft KB 875424 for preferred workaround. 1342280849Scy */ 1343280849Scy if (AUTH(restrict_mask & RES_DONTTRUST, 1344280849Scy is_authentic)) { 1345280849Scy fast_xmit(rbufp, MODE_PASSIVE, skeyid, 1346280849Scy restrict_mask); 1347280849Scy return; /* hooray */ 1348280849Scy } 1349280849Scy if (is_authentic == AUTH_ERROR) { 1350182007Sroberto fast_xmit(rbufp, MODE_ACTIVE, 0, 1351182007Sroberto restrict_mask); 1352280849Scy sys_restricted++; 1353280849Scy return; 1354280849Scy } 1355289764Sglebius /* [Bug 2941] 1356289764Sglebius * If we got here, the packet isn't part of an 1357289764Sglebius * existing association, it isn't correctly 1358289764Sglebius * authenticated, and it didn't meet either of 1359289764Sglebius * the previous two special cases so we should 1360289764Sglebius * just drop it on the floor. For example, 1361289764Sglebius * crypto-NAKs (is_authentic == AUTH_CRYPTO) 1362289764Sglebius * will make it this far. This is just 1363289764Sglebius * debug-printed and not logged to avoid log 1364289764Sglebius * flooding. 1365289764Sglebius */ 1366293423Sdelphij DPRINTF(2, ("receive: at %ld refusing to mobilize passive association" 1367293423Sdelphij " with unknown peer %s mode %d/%s:%s keyid %08x len %d auth %d\n", 1368289764Sglebius current_time, stoa(&rbufp->recv_srcadr), 1369293423Sdelphij hismode, hm_str, am_str, skeyid, 1370293423Sdelphij (authlen + has_mac), is_authentic)); 1371289764Sglebius sys_declined++; 1372289764Sglebius return; 1373182007Sroberto } 1374280849Scy 1375280849Scy /* 1376280849Scy * Do not respond if synchronized and if stratum is 1377280849Scy * below the floor or at or above the ceiling. Note, 1378280849Scy * this allows an unsynchronized peer to synchronize to 1379280849Scy * us. It would be very strange if he did and then was 1380280849Scy * nipped, but that could only happen if we were 1381280849Scy * operating at the top end of the range. It also means 1382280849Scy * we will spin an ephemeral association in response to 1383280849Scy * MODE_ACTIVE KoDs, which will time out eventually. 1384280849Scy */ 1385289764Sglebius if ( hisleap != LEAP_NOTINSYNC 1386289764Sglebius && (hisstratum < sys_floor || hisstratum >= sys_ceiling)) { 1387280849Scy sys_declined++; 1388280849Scy return; /* no help */ 1389182007Sroberto } 139054359Sroberto 1391182007Sroberto /* 1392280849Scy * The message is correctly authenticated and allowed. 1393280849Scy * Mobilize a symmetric passive association. 1394182007Sroberto */ 1395280849Scy if ((peer = newpeer(&rbufp->recv_srcadr, NULL, 1396280849Scy rbufp->dstadr, MODE_PASSIVE, hisversion, pkt->ppoll, 1397280849Scy NTP_MAXDPOLL, 0, MDF_UCAST, 0, skeyid, 1398280849Scy sys_ident)) == NULL) { 1399280849Scy sys_declined++; 1400280849Scy return; /* ignore duplicate */ 1401280849Scy } 1402182007Sroberto break; 1403182007Sroberto 1404280849Scy 140554359Sroberto /* 1406182007Sroberto * Process regular packet. Nothing special. 140754359Sroberto */ 1408182007Sroberto case AM_PROCPKT: 1409280849Scy 1410280849Scy#ifdef AUTOKEY 1411280849Scy /* 1412280849Scy * Do not respond if not the same group. 1413280849Scy */ 1414280849Scy if (group_test(groupname, peer->ident)) { 1415280849Scy sys_declined++; 1416280849Scy return; 1417280849Scy } 1418280849Scy#endif /* AUTOKEY */ 1419294554Sdelphij 1420294554Sdelphij if (MODE_BROADCAST == hismode) { 1421298695Sdelphij int bail = 0; 1422298695Sdelphij l_fp tdiff; 1423298695Sdelphij u_long deadband; 1424294554Sdelphij 1425294554Sdelphij DPRINTF(2, ("receive: PROCPKT/BROADCAST: prev pkt %ld seconds ago, ppoll: %d, %d secs\n", 1426294554Sdelphij (current_time - peer->timelastrec), 1427294554Sdelphij peer->ppoll, (1 << peer->ppoll) 1428294554Sdelphij )); 1429294554Sdelphij /* Things we can check: 1430294554Sdelphij * 1431294554Sdelphij * Did the poll interval change? 1432294554Sdelphij * Is the poll interval in the packet in-range? 1433294554Sdelphij * Did this packet arrive too soon? 1434294554Sdelphij * Is the timestamp in this packet monotonic 1435294554Sdelphij * with respect to the previous packet? 1436294554Sdelphij */ 1437294554Sdelphij 1438294554Sdelphij /* This is noteworthy, not error-worthy */ 1439294554Sdelphij if (pkt->ppoll != peer->ppoll) { 1440294554Sdelphij msyslog(LOG_INFO, "receive: broadcast poll from %s changed from %ud to %ud", 1441294554Sdelphij stoa(&rbufp->recv_srcadr), 1442294554Sdelphij peer->ppoll, pkt->ppoll); 1443294554Sdelphij } 1444294554Sdelphij 1445294554Sdelphij /* This is error-worthy */ 1446298695Sdelphij if (pkt->ppoll < peer->minpoll || 1447298695Sdelphij pkt->ppoll > peer->maxpoll ) { 1448294554Sdelphij msyslog(LOG_INFO, "receive: broadcast poll of %ud from %s is out-of-range (%d to %d)!", 1449294554Sdelphij pkt->ppoll, stoa(&rbufp->recv_srcadr), 1450294554Sdelphij peer->minpoll, peer->maxpoll); 1451294554Sdelphij ++bail; 1452294554Sdelphij } 1453294554Sdelphij 1454309007Sdelphij /* too early? worth an error, too! 1455309007Sdelphij * 1456309007Sdelphij * [Bug 3113] Ensure that at least one poll 1457309007Sdelphij * interval has elapsed since the last **clean** 1458309007Sdelphij * packet was received. We limit the check to 1459309007Sdelphij * **clean** packets to prevent replayed packets 1460309007Sdelphij * and incorrectly authenticated packets, which 1461309007Sdelphij * we'll discard, from being used to create a 1462309007Sdelphij * denial of service condition. 1463309007Sdelphij */ 1464298695Sdelphij deadband = (1u << pkt->ppoll); 1465298695Sdelphij if (FLAG_BC_VOL & peer->flags) 1466298695Sdelphij deadband -= 3; /* allow greater fuzz after volley */ 1467309007Sdelphij if ((current_time - peer->timereceived) < deadband) { 1468298695Sdelphij msyslog(LOG_INFO, "receive: broadcast packet from %s arrived after %lu, not %lu seconds!", 1469294554Sdelphij stoa(&rbufp->recv_srcadr), 1470309007Sdelphij (current_time - peer->timereceived), 1471298695Sdelphij deadband); 1472294554Sdelphij ++bail; 1473294554Sdelphij } 1474294554Sdelphij 1475309007Sdelphij /* Alert if time from the server is non-monotonic. 1476309007Sdelphij * 1477309007Sdelphij * [Bug 3114] is about Broadcast mode replay DoS. 1478309007Sdelphij * 1479309007Sdelphij * Broadcast mode *assumes* a trusted network. 1480309007Sdelphij * Even so, it's nice to be robust in the face 1481309007Sdelphij * of attacks. 1482309007Sdelphij * 1483309007Sdelphij * If we get an authenticated broadcast packet 1484309007Sdelphij * with an "earlier" timestamp, it means one of 1485309007Sdelphij * two things: 1486309007Sdelphij * 1487309007Sdelphij * - the broadcast server had a backward step. 1488309007Sdelphij * 1489309007Sdelphij * - somebody is trying a replay attack. 1490309007Sdelphij * 1491309007Sdelphij * deadband: By default, we assume the broadcast 1492309007Sdelphij * network is trustable, so we take our accepted 1493309007Sdelphij * broadcast packets as we receive them. But 1494309007Sdelphij * some folks might want to take additional poll 1495309007Sdelphij * delays before believing a backward step. 1496309007Sdelphij */ 1497309007Sdelphij if (sys_bcpollbstep) { 1498309007Sdelphij /* pkt->ppoll or peer->ppoll ? */ 1499309007Sdelphij deadband = (1u << pkt->ppoll) 1500309007Sdelphij * sys_bcpollbstep + 2; 1501309007Sdelphij } else { 1502309007Sdelphij deadband = 0; 1503309007Sdelphij } 1504309007Sdelphij 1505309007Sdelphij if (L_ISZERO(&peer->bxmt)) { 1506309007Sdelphij tdiff.l_ui = tdiff.l_uf = 0; 1507309007Sdelphij } else { 1508309007Sdelphij tdiff = p_xmt; 1509309007Sdelphij L_SUB(&tdiff, &peer->bxmt); 1510309007Sdelphij } 1511309007Sdelphij if (tdiff.l_i < 0 && 1512309007Sdelphij (current_time - peer->timereceived) < deadband) 1513309007Sdelphij { 1514294554Sdelphij msyslog(LOG_INFO, "receive: broadcast packet from %s contains non-monotonic timestamp: %#010x.%08x -> %#010x.%08x", 1515294554Sdelphij stoa(&rbufp->recv_srcadr), 1516294554Sdelphij peer->bxmt.l_ui, peer->bxmt.l_uf, 1517294554Sdelphij p_xmt.l_ui, p_xmt.l_uf 1518294554Sdelphij ); 1519294554Sdelphij ++bail; 1520294554Sdelphij } 1521294554Sdelphij 1522294554Sdelphij if (bail) { 1523294554Sdelphij peer->timelastrec = current_time; 1524294554Sdelphij sys_declined++; 1525294554Sdelphij return; 1526294554Sdelphij } 1527294554Sdelphij } 1528294554Sdelphij 1529182007Sroberto break; 153054359Sroberto 153154359Sroberto /* 1532182007Sroberto * A passive packet matches a passive association. This is 1533182007Sroberto * usually the result of reconfiguring a client on the fly. As 1534280849Scy * this association might be legitimate and this packet an 1535182007Sroberto * attempt to deny service, just ignore it. 153654359Sroberto */ 1537182007Sroberto case AM_ERR: 1538280849Scy sys_declined++; 1539182007Sroberto return; 1540132454Sroberto 1541132454Sroberto /* 1542182007Sroberto * For everything else there is the bit bucket. 1543132454Sroberto */ 1544182007Sroberto default: 1545280849Scy sys_declined++; 1546182007Sroberto return; 1547182007Sroberto } 1548280849Scy 1549280849Scy#ifdef AUTOKEY 1550280849Scy /* 1551280849Scy * If the association is configured for Autokey, the packet must 1552280849Scy * have a public key ID; if not, the packet must have a 1553280849Scy * symmetric key ID. 1554280849Scy */ 1555289764Sglebius if ( is_authentic != AUTH_CRYPTO 1556289764Sglebius && ( ((peer->flags & FLAG_SKEY) && skeyid <= NTP_MAXKEY) 1557289764Sglebius || (!(peer->flags & FLAG_SKEY) && skeyid > NTP_MAXKEY))) { 1558280849Scy sys_badauth++; 1559280849Scy return; 1560280849Scy } 1561280849Scy#endif /* AUTOKEY */ 1562298695Sdelphij 1563280849Scy peer->received++; 1564182007Sroberto peer->flash &= ~PKT_TEST_MASK; 1565280849Scy if (peer->flags & FLAG_XBOGUS) { 1566280849Scy peer->flags &= ~FLAG_XBOGUS; 1567280849Scy peer->flash |= TEST3; 1568280849Scy } 1569132454Sroberto 1570132454Sroberto /* 1571182007Sroberto * Next comes a rigorous schedule of timestamp checking. If the 1572280849Scy * transmit timestamp is zero, the server has not initialized in 1573280849Scy * interleaved modes or is horribly broken. 1574298695Sdelphij * 1575298695Sdelphij * A KoD packet we pay attention to cannot have a 0 transmit 1576298695Sdelphij * timestamp. 1577132454Sroberto */ 1578182007Sroberto if (L_ISZERO(&p_xmt)) { 1579280849Scy peer->flash |= TEST3; /* unsynch */ 1580301247Sdelphij if (STRATUM_UNSPEC == hisstratum) { /* KoD packet */ 1581298695Sdelphij peer->bogusorg++; /* for TEST2 or TEST3 */ 1582298695Sdelphij msyslog(LOG_INFO, 1583298695Sdelphij "receive: Unexpected zero transmit timestamp in KoD from %s", 1584298695Sdelphij ntoa(&peer->srcadr)); 1585298695Sdelphij return; 1586298695Sdelphij } 1587132454Sroberto 1588132454Sroberto /* 1589298695Sdelphij * If the transmit timestamp duplicates our previous one, the 1590182007Sroberto * packet is a replay. This prevents the bad guys from replaying 1591182007Sroberto * the most recent packet, authenticated or not. 1592132454Sroberto */ 1593280849Scy } else if (L_ISEQU(&peer->xmt, &p_xmt)) { 1594280849Scy peer->flash |= TEST1; /* duplicate */ 1595182007Sroberto peer->oldpkt++; 1596280849Scy return; 1597132454Sroberto 1598132454Sroberto /* 1599301247Sdelphij * If this is a broadcast mode packet, make sure hisstratum 1600301247Sdelphij * is appropriate. Don't do anything else here - we wait to 1601301247Sdelphij * see if this is an interleave broadcast packet until after 1602301247Sdelphij * we've validated the MAC that SHOULD be provided. 1603301247Sdelphij * 1604301247Sdelphij * hisstratum should never be 0. 1605301247Sdelphij * If hisstratum is 15, then we'll advertise as UNSPEC but 1606301247Sdelphij * at least we'll be able to sync with the broadcast server. 1607132454Sroberto */ 1608280849Scy } else if (hismode == MODE_BROADCAST) { 1609301247Sdelphij if ( 0 == hisstratum 1610301247Sdelphij || STRATUM_UNSPEC <= hisstratum) { 1611301247Sdelphij /* Is this a ++sys_declined or ??? */ 1612301247Sdelphij msyslog(LOG_INFO, 1613301247Sdelphij "receive: Unexpected stratum (%d) in broadcast from %s", 1614301247Sdelphij hisstratum, ntoa(&peer->srcadr)); 1615280849Scy return; 1616280849Scy } 1617132454Sroberto 1618132454Sroberto /* 1619298695Sdelphij * Basic KoD validation checking: 1620298695Sdelphij * 1621298695Sdelphij * KoD packets are a mixed-blessing. Forged KoD packets 1622298695Sdelphij * are DoS attacks. There are rare situations where we might 1623298695Sdelphij * get a valid KoD response, though. Since KoD packets are 1624298695Sdelphij * a special case that complicate the checks we do next, we 1625298695Sdelphij * handle the basic KoD checks here. 1626298695Sdelphij * 1627298695Sdelphij * Note that we expect the incoming KoD packet to have its 1628298695Sdelphij * (nonzero) org, rec, and xmt timestamps set to the xmt timestamp 1629298695Sdelphij * that we have previously sent out. Watch interleave mode. 1630298695Sdelphij */ 1631301247Sdelphij } else if (STRATUM_UNSPEC == hisstratum) { 1632298695Sdelphij DEBUG_INSIST(!L_ISZERO(&p_xmt)); 1633298695Sdelphij if ( L_ISZERO(&p_org) /* We checked p_xmt above */ 1634298695Sdelphij || L_ISZERO(&p_rec)) { 1635298695Sdelphij peer->bogusorg++; 1636298695Sdelphij msyslog(LOG_INFO, 1637298695Sdelphij "receive: KoD packet from %s has a zero org or rec timestamp. Ignoring.", 1638298695Sdelphij ntoa(&peer->srcadr)); 1639298695Sdelphij return; 1640298695Sdelphij } 1641298695Sdelphij 1642298695Sdelphij if ( !L_ISEQU(&p_xmt, &p_org) 1643298695Sdelphij || !L_ISEQU(&p_xmt, &p_rec)) { 1644298695Sdelphij peer->bogusorg++; 1645298695Sdelphij msyslog(LOG_INFO, 1646298695Sdelphij "receive: KoD packet from %s has inconsistent xmt/org/rec timestamps. Ignoring.", 1647298695Sdelphij ntoa(&peer->srcadr)); 1648298695Sdelphij return; 1649298695Sdelphij } 1650298695Sdelphij 1651298695Sdelphij /* Be conservative */ 1652298695Sdelphij if (peer->flip == 0 && !L_ISEQU(&p_org, &peer->aorg)) { 1653298695Sdelphij peer->bogusorg++; 1654298695Sdelphij msyslog(LOG_INFO, 1655298695Sdelphij "receive: flip 0 KoD origin timestamp %#010x.%08x from %s does not match %#010x.%08x - ignoring.", 1656298695Sdelphij p_org.l_ui, p_org.l_uf, 1657298695Sdelphij ntoa(&peer->srcadr), 1658298695Sdelphij peer->aorg.l_ui, peer->aorg.l_uf); 1659298695Sdelphij return; 1660298695Sdelphij } else if (peer->flip == 1 && !L_ISEQU(&p_org, &peer->borg)) { 1661298695Sdelphij peer->bogusorg++; 1662298695Sdelphij msyslog(LOG_INFO, 1663298695Sdelphij "receive: flip 1 KoD origin timestamp %#010x.%08x from %s does not match interleave %#010x.%08x - ignoring.", 1664298695Sdelphij p_org.l_ui, p_org.l_uf, 1665298695Sdelphij ntoa(&peer->srcadr), 1666298695Sdelphij peer->borg.l_ui, peer->borg.l_uf); 1667298695Sdelphij return; 1668298695Sdelphij } 1669309007Sdelphij 1670298695Sdelphij /* 1671293423Sdelphij * Basic mode checks: 1672289764Sglebius * 1673294554Sdelphij * If there is no origin timestamp, it's either an initial packet 1674294554Sdelphij * or we've already received a response to our query. Of course, 1675294554Sdelphij * should 'aorg' be all-zero because this really was the original 1676298695Sdelphij * transmit timestamp, we'll ignore this reply. There is a window 1677298695Sdelphij * of one nanosecond once every 136 years' time where this is 1678298695Sdelphij * possible. We currently ignore this situation. 1679293423Sdelphij * 1680293423Sdelphij * Otherwise, check for bogus packet in basic mode. 1681293423Sdelphij * If it is bogus, switch to interleaved mode and resynchronize, 1682293423Sdelphij * but only after confirming the packet is not bogus in 1683293423Sdelphij * symmetric interleaved mode. 1684293423Sdelphij * 1685289764Sglebius * This could also mean somebody is forging packets claiming to 1686289764Sglebius * be from us, attempting to cause our server to KoD us. 1687132454Sroberto */ 1688280849Scy } else if (peer->flip == 0) { 1689298695Sdelphij INSIST(0 != hisstratum); 1690301247Sdelphij INSIST(STRATUM_UNSPEC != hisstratum); 1691309007Sdelphij 1692298695Sdelphij if (0) { 1693298695Sdelphij } else if (L_ISZERO(&p_org)) { 1694309007Sdelphij char *action; 1695309007Sdelphij 1696309007Sdelphij L_CLR(&peer->aorg); 1697309007Sdelphij /**/ 1698309007Sdelphij switch (hismode) { 1699309007Sdelphij /* We allow 0org for: */ 1700309007Sdelphij case UCHAR_MAX: 1701309007Sdelphij action = "Allow"; 1702309007Sdelphij break; 1703309007Sdelphij /* We disallow 0org for: */ 1704309007Sdelphij case MODE_UNSPEC: 1705309007Sdelphij case MODE_ACTIVE: 1706309007Sdelphij case MODE_PASSIVE: 1707309007Sdelphij case MODE_CLIENT: 1708309007Sdelphij case MODE_SERVER: 1709309007Sdelphij case MODE_BROADCAST: 1710309007Sdelphij action = "Drop"; 1711309007Sdelphij peer->bogusorg++; 1712309007Sdelphij peer->flash |= TEST2; /* bogus */ 1713309007Sdelphij break; 1714309007Sdelphij default: 1715309007Sdelphij INSIST(!"receive(): impossible hismode"); 1716309007Sdelphij break; 1717309007Sdelphij } 1718309007Sdelphij /**/ 1719298695Sdelphij msyslog(LOG_INFO, 1720309007Sdelphij "receive: %s 0 origin timestamp from %s@%s xmt %#010x.%08x", 1721309007Sdelphij action, hm_str, ntoa(&peer->srcadr), 1722298695Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf)); 1723298695Sdelphij } else if (!L_ISEQU(&p_org, &peer->aorg)) { 1724298695Sdelphij /* are there cases here where we should bail? */ 1725298695Sdelphij /* Should we set TEST2 if we decide to try xleave? */ 1726280849Scy peer->bogusorg++; 1727280849Scy peer->flash |= TEST2; /* bogus */ 1728289764Sglebius msyslog(LOG_INFO, 1729298695Sdelphij "receive: Unexpected origin timestamp %#010x.%08x does not match aorg %#010x.%08x from %s@%s xmt %#010x.%08x", 1730293423Sdelphij ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf), 1731298695Sdelphij peer->aorg.l_ui, peer->aorg.l_uf, 1732298695Sdelphij hm_str, ntoa(&peer->srcadr), 1733293423Sdelphij ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf)); 1734289764Sglebius if ( !L_ISZERO(&peer->dst) 1735289764Sglebius && L_ISEQU(&p_org, &peer->dst)) { 1736293423Sdelphij /* Might be the start of an interleave */ 1737298695Sdelphij if (dynamic_interleave) { 1738298695Sdelphij peer->flip = 1; 1739298695Sdelphij report_event(PEVNT_XLEAVE, peer, NULL); 1740298695Sdelphij } else { 1741298695Sdelphij msyslog(LOG_INFO, 1742298695Sdelphij "receive: Dynamic interleave from %s@%s denied", 1743298695Sdelphij hm_str, ntoa(&peer->srcadr)); 1744298695Sdelphij } 1745182007Sroberto } 1746280849Scy } else { 1747280849Scy L_CLR(&peer->aorg); 1748182007Sroberto } 1749280849Scy 1750280849Scy /* 1751280849Scy * Check for valid nonzero timestamp fields. 1752280849Scy */ 1753301247Sdelphij } else if ( L_ISZERO(&p_org) 1754301247Sdelphij || L_ISZERO(&p_rec) 1755301247Sdelphij || L_ISZERO(&peer->dst)) { 1756280849Scy peer->flash |= TEST3; /* unsynch */ 1757280849Scy 1758280849Scy /* 1759280849Scy * Check for bogus packet in interleaved symmetric mode. This 1760280849Scy * can happen if a packet is lost, duplicated or crossed. If 1761280849Scy * found, flip and resynchronize. 1762280849Scy */ 1763289764Sglebius } else if ( !L_ISZERO(&peer->dst) 1764289764Sglebius && !L_ISEQU(&p_org, &peer->dst)) { 1765280849Scy peer->bogusorg++; 1766280849Scy peer->flags |= FLAG_XBOGUS; 1767280849Scy peer->flash |= TEST2; /* bogus */ 1768289764Sglebius return; /* Bogus packet, we are done */ 1769182007Sroberto } 1770132454Sroberto 1771301247Sdelphij /**/ 1772301247Sdelphij 1773132454Sroberto /* 1774280849Scy * If this is a crypto_NAK, the server cannot authenticate a 1775280849Scy * client packet. The server might have just changed keys. Clear 1776280849Scy * the association and restart the protocol. 1777280849Scy */ 1778298695Sdelphij if (crypto_nak_test == VALIDNAK) { 1779280849Scy report_event(PEVNT_AUTH, peer, "crypto_NAK"); 1780280849Scy peer->flash |= TEST5; /* bad auth */ 1781280849Scy peer->badauth++; 1782280849Scy if (peer->flags & FLAG_PREEMPT) { 1783294554Sdelphij if (unpeer_crypto_nak_early) { 1784294554Sdelphij unpeer(peer); 1785294554Sdelphij } 1786280849Scy return; 1787280849Scy } 1788280849Scy#ifdef AUTOKEY 1789301247Sdelphij if (peer->crypto) { 1790280849Scy peer_clear(peer, "AUTH"); 1791301247Sdelphij } 1792280849Scy#endif /* AUTOKEY */ 1793280849Scy return; 1794182007Sroberto 1795282408Scy /* 1796282408Scy * If the digest fails or it's missing for authenticated 1797282408Scy * associations, the client cannot authenticate a server 1798280849Scy * reply to a client packet previously sent. The loopback check 1799280849Scy * is designed to avoid a bait-and-switch attack, which was 1800280849Scy * possible in past versions. If symmetric modes, return a 1801280849Scy * crypto-NAK. The peer should restart the protocol. 1802182007Sroberto */ 1803282408Scy } else if (!AUTH(peer->keyid || has_mac || 1804282408Scy (restrict_mask & RES_DONTTRUST), is_authentic)) { 1805301247Sdelphij 1806301247Sdelphij if (peer->flash & PKT_TEST_MASK) { 1807301247Sdelphij msyslog(LOG_INFO, 1808301247Sdelphij "receive: Bad auth in packet with bad timestamps from %s denied - spoof?", 1809301247Sdelphij ntoa(&peer->srcadr)); 1810301247Sdelphij return; 1811301247Sdelphij } 1812301247Sdelphij 1813280849Scy report_event(PEVNT_AUTH, peer, "digest"); 1814280849Scy peer->flash |= TEST5; /* bad auth */ 1815280849Scy peer->badauth++; 1816289764Sglebius if ( has_mac 1817301247Sdelphij && ( hismode == MODE_ACTIVE 1818301247Sdelphij || hismode == MODE_PASSIVE)) 1819132454Sroberto fast_xmit(rbufp, MODE_ACTIVE, 0, restrict_mask); 1820280849Scy if (peer->flags & FLAG_PREEMPT) { 1821294554Sdelphij if (unpeer_digest_early) { 1822294554Sdelphij unpeer(peer); 1823294554Sdelphij } 1824280849Scy } 1825280849Scy#ifdef AUTOKEY 1826301247Sdelphij else if (peer_clear_digest_early && peer->crypto) { 1827280849Scy peer_clear(peer, "AUTH"); 1828301247Sdelphij } 1829280849Scy#endif /* AUTOKEY */ 1830280849Scy return; 183154359Sroberto } 183254359Sroberto 1833182007Sroberto /* 1834301247Sdelphij * For broadcast packets: 1835301247Sdelphij * 1836301247Sdelphij * HMS: This next line never made much sense to me, even 1837301247Sdelphij * when it was up higher: 1838301247Sdelphij * If an initial volley, bail out now and let the 1839301247Sdelphij * client do its stuff. 1840301247Sdelphij * 1841301247Sdelphij * If the packet has not failed authentication, then 1842301247Sdelphij * - if the origin timestamp is nonzero this is an 1843301247Sdelphij * interleaved broadcast, so restart the protocol. 1844301247Sdelphij * - else, this is not an interleaved broadcast packet. 1845282408Scy */ 1846301247Sdelphij if (hismode == MODE_BROADCAST) { 1847301247Sdelphij if ( is_authentic == AUTH_OK 1848301247Sdelphij || is_authentic == AUTH_NONE) { 1849301247Sdelphij if (!L_ISZERO(&p_org)) { 1850301247Sdelphij if (!(peer->flags & FLAG_XB)) { 1851301247Sdelphij msyslog(LOG_INFO, 1852301247Sdelphij "receive: Broadcast server at %s is in interleave mode", 1853301247Sdelphij ntoa(&peer->srcadr)); 1854301247Sdelphij peer->flags |= FLAG_XB; 1855301247Sdelphij peer->aorg = p_xmt; 1856301247Sdelphij peer->borg = rbufp->recv_time; 1857301247Sdelphij report_event(PEVNT_XLEAVE, peer, NULL); 1858301247Sdelphij return; 1859301247Sdelphij } 1860301247Sdelphij } else if (peer->flags & FLAG_XB) { 1861301247Sdelphij msyslog(LOG_INFO, 1862301247Sdelphij "receive: Broadcast server at %s is no longer in interleave mode", 1863301247Sdelphij ntoa(&peer->srcadr)); 1864301247Sdelphij peer->flags &= ~FLAG_XB; 1865301247Sdelphij } 1866301247Sdelphij } else { 1867301247Sdelphij msyslog(LOG_INFO, 1868301247Sdelphij "receive: Bad broadcast auth (%d) from %s", 1869301247Sdelphij is_authentic, ntoa(&peer->srcadr)); 1870301247Sdelphij } 1871309007Sdelphij 1872309007Sdelphij /* 1873309007Sdelphij * Now that we know the packet is correctly authenticated, 1874309007Sdelphij * update peer->bxmt. 1875309007Sdelphij */ 1876309007Sdelphij peer->bxmt = p_xmt; 1877301247Sdelphij } 1878301247Sdelphij 1879301247Sdelphij 1880301247Sdelphij /* 1881301247Sdelphij ** Update the state variables. 1882301247Sdelphij */ 1883282408Scy if (peer->flip == 0) { 1884282408Scy if (hismode != MODE_BROADCAST) 1885282408Scy peer->rec = p_xmt; 1886282408Scy peer->dst = rbufp->recv_time; 1887282408Scy } 1888282408Scy peer->xmt = p_xmt; 1889282408Scy 1890282408Scy /* 1891280849Scy * Set the peer ppoll to the maximum of the packet ppoll and the 1892280849Scy * peer minpoll. If a kiss-o'-death, set the peer minpoll to 1893280849Scy * this maximum and advance the headway to give the sender some 1894280849Scy * headroom. Very intricate. 1895280849Scy */ 1896289764Sglebius 1897289764Sglebius /* 1898289764Sglebius * Check for any kiss codes. Note this is only used when a server 1899289764Sglebius * responds to a packet request 1900289764Sglebius */ 1901289764Sglebius 1902289764Sglebius kissCode = kiss_code_check(hisleap, hisstratum, hismode, pkt->refid); 1903289764Sglebius 1904289764Sglebius /* 1905289764Sglebius * Check to see if this is a RATE Kiss Code 1906289764Sglebius * Currently this kiss code will accept whatever poll 1907289764Sglebius * rate that the server sends 1908289764Sglebius */ 1909280849Scy peer->ppoll = max(peer->minpoll, pkt->ppoll); 1910289764Sglebius if (kissCode == RATEKISS) { 1911289764Sglebius peer->selbroken++; /* Increment the KoD count */ 1912280849Scy report_event(PEVNT_RATE, peer, NULL); 1913280849Scy if (pkt->ppoll > peer->minpoll) 1914280849Scy peer->minpoll = peer->ppoll; 1915280849Scy peer->burst = peer->retry = 0; 1916280849Scy peer->throttle = (NTP_SHIFT + 1) * (1 << peer->minpoll); 1917280849Scy poll_update(peer, pkt->ppoll); 1918280849Scy return; /* kiss-o'-death */ 1919280849Scy } 1920289764Sglebius if (kissCode != NOKISS) { 1921289764Sglebius peer->selbroken++; /* Increment the KoD count */ 1922289764Sglebius return; /* Drop any other kiss code packets */ 1923289764Sglebius } 1924280849Scy 1925301247Sdelphij 1926294554Sdelphij /* 1927301247Sdelphij * XXX 1928301247Sdelphij */ 1929301247Sdelphij 1930301247Sdelphij 1931301247Sdelphij /* 1932294554Sdelphij * If: 1933294554Sdelphij * - this is a *cast (uni-, broad-, or m-) server packet 1934298695Sdelphij * - and it's symmetric-key authenticated 1935294554Sdelphij * then see if the sender's IP is trusted for this keyid. 1936294554Sdelphij * If it is, great - nothing special to do here. 1937294554Sdelphij * Otherwise, we should report and bail. 1938298695Sdelphij * 1939298695Sdelphij * Autokey-authenticated packets are accepted. 1940294554Sdelphij */ 1941289764Sglebius 1942294554Sdelphij switch (hismode) { 1943294554Sdelphij case MODE_SERVER: /* server mode */ 1944294554Sdelphij case MODE_BROADCAST: /* broadcast mode */ 1945294554Sdelphij case MODE_ACTIVE: /* symmetric active mode */ 1946298695Sdelphij case MODE_PASSIVE: /* symmetric passive mode */ 1947294554Sdelphij if ( is_authentic == AUTH_OK 1948298695Sdelphij && skeyid 1949298695Sdelphij && skeyid <= NTP_MAXKEY 1950294554Sdelphij && !authistrustedip(skeyid, &peer->srcadr)) { 1951294554Sdelphij report_event(PEVNT_AUTH, peer, "authIP"); 1952294554Sdelphij peer->badauth++; 1953294554Sdelphij return; 1954294554Sdelphij } 1955309007Sdelphij break; 1956294554Sdelphij 1957294554Sdelphij case MODE_CLIENT: /* client mode */ 1958294554Sdelphij#if 0 /* At this point, MODE_CONTROL is overloaded by MODE_BCLIENT */ 1959294554Sdelphij case MODE_CONTROL: /* control mode */ 1960294554Sdelphij#endif 1961294554Sdelphij case MODE_PRIVATE: /* private mode */ 1962294554Sdelphij case MODE_BCLIENT: /* broadcast client mode */ 1963309007Sdelphij break; 1964298695Sdelphij 1965298695Sdelphij case MODE_UNSPEC: /* unspecified (old version) */ 1966294554Sdelphij default: 1967298695Sdelphij msyslog(LOG_INFO, 1968298695Sdelphij "receive: Unexpected mode (%d) in packet from %s", 1969298695Sdelphij hismode, ntoa(&peer->srcadr)); 1970309007Sdelphij break; 1971294554Sdelphij } 1972294554Sdelphij 1973294554Sdelphij 1974280849Scy /* 1975182007Sroberto * That was hard and I am sweaty, but the packet is squeaky 1976182007Sroberto * clean. Get on with real work. 1977182007Sroberto */ 1978182007Sroberto peer->timereceived = current_time; 1979294554Sdelphij peer->timelastrec = current_time; 1980182007Sroberto if (is_authentic == AUTH_OK) 1981182007Sroberto peer->flags |= FLAG_AUTHENTIC; 1982182007Sroberto else 1983182007Sroberto peer->flags &= ~FLAG_AUTHENTIC; 1984280849Scy 1985280849Scy#ifdef AUTOKEY 198654359Sroberto /* 198782505Sroberto * More autokey dance. The rules of the cha-cha are as follows: 198882505Sroberto * 198982505Sroberto * 1. If there is no key or the key is not auto, do nothing. 199082505Sroberto * 1991132454Sroberto * 2. If this packet is in response to the one just previously 1992132454Sroberto * sent or from a broadcast server, do the extension fields. 1993132454Sroberto * Otherwise, assume bogosity and bail out. 1994132454Sroberto * 1995132454Sroberto * 3. If an extension field contains a verified signature, it is 199682505Sroberto * self-authenticated and we sit the dance. 199782505Sroberto * 1998132454Sroberto * 4. If this is a server reply, check only to see that the 199982505Sroberto * transmitted key ID matches the received key ID. 200082505Sroberto * 2001132454Sroberto * 5. Check to see that one or more hashes of the current key ID 200282505Sroberto * matches the previous key ID or ultimate original key ID 200382505Sroberto * obtained from the broadcaster or symmetric peer. If no 2004280849Scy * match, sit the dance and call for new autokey values. 2005182007Sroberto * 2006280849Scy * In case of crypto error, fire the orchestra, stop dancing and 2007280849Scy * restart the protocol. 200854359Sroberto */ 2009280849Scy if (peer->flags & FLAG_SKEY) { 2010280849Scy /* 2011280849Scy * Decrement remaining autokey hashes. This isn't 2012280849Scy * perfect if a packet is lost, but results in no harm. 2013280849Scy */ 2014280849Scy ap = (struct autokey *)peer->recval.ptr; 2015280849Scy if (ap != NULL) { 2016280849Scy if (ap->seq > 0) 2017280849Scy ap->seq--; 2018280849Scy } 2019182007Sroberto peer->flash |= TEST8; 2020132454Sroberto rval = crypto_recv(peer, rbufp); 2021280849Scy if (rval == XEVNT_OK) { 2022280849Scy peer->unreach = 0; 2023280849Scy } else { 2024280849Scy if (rval == XEVNT_ERR) { 2025280849Scy report_event(PEVNT_RESTART, peer, 2026280849Scy "crypto error"); 2027280849Scy peer_clear(peer, "CRYP"); 2028280849Scy peer->flash |= TEST9; /* bad crypt */ 2029294554Sdelphij if (peer->flags & FLAG_PREEMPT) { 2030294554Sdelphij if (unpeer_crypto_early) { 2031294554Sdelphij unpeer(peer); 2032294554Sdelphij } 2033294554Sdelphij } 2034280849Scy } 2035182007Sroberto return; 2036280849Scy } 2037132454Sroberto 2038280849Scy /* 2039280849Scy * If server mode, verify the receive key ID matches 2040280849Scy * the transmit key ID. 2041280849Scy */ 2042280849Scy if (hismode == MODE_SERVER) { 204382505Sroberto if (skeyid == peer->keyid) 2044182007Sroberto peer->flash &= ~TEST8; 2045280849Scy 2046280849Scy /* 2047280849Scy * If an extension field is present, verify only that it 2048280849Scy * has been correctly signed. We don't need a sequence 2049280849Scy * check here, but the sequence continues. 2050280849Scy */ 2051182007Sroberto } else if (!(peer->flash & TEST8)) { 205282505Sroberto peer->pkeyid = skeyid; 2053280849Scy 2054280849Scy /* 2055280849Scy * Now the fun part. Here, skeyid is the current ID in 2056280849Scy * the packet, pkeyid is the ID in the last packet and 2057280849Scy * tkeyid is the hash of skeyid. If the autokey values 2058280849Scy * have not been received, this is an automatic error. 2059280849Scy * If so, check that the tkeyid matches pkeyid. If not, 2060280849Scy * hash tkeyid and try again. If the number of hashes 2061280849Scy * exceeds the number remaining in the sequence, declare 2062280849Scy * a successful failure and refresh the autokey values. 2063280849Scy */ 2064280849Scy } else if (ap != NULL) { 206582505Sroberto int i; 206682505Sroberto 206782505Sroberto for (i = 0; ; i++) { 2068289764Sglebius if ( tkeyid == peer->pkeyid 2069289764Sglebius || tkeyid == ap->key) { 2070182007Sroberto peer->flash &= ~TEST8; 207182505Sroberto peer->pkeyid = skeyid; 2072280849Scy ap->seq -= i; 207382505Sroberto break; 207482505Sroberto } 2075280849Scy if (i > ap->seq) { 2076280849Scy peer->crypto &= 2077280849Scy ~CRYPTO_FLAG_AUTO; 207882505Sroberto break; 2079280849Scy } 208054359Sroberto tkeyid = session_key( 208182505Sroberto &rbufp->recv_srcadr, dstadr_sin, 208282505Sroberto tkeyid, pkeyid, 0); 208354359Sroberto } 2084280849Scy if (peer->flash & TEST8) 2085280849Scy report_event(PEVNT_AUTH, peer, "keylist"); 208654359Sroberto } 2087182007Sroberto if (!(peer->crypto & CRYPTO_FLAG_PROV)) /* test 9 */ 2088280849Scy peer->flash |= TEST8; /* bad autokey */ 208982505Sroberto 209082505Sroberto /* 2091280849Scy * The maximum lifetime of the protocol is about one 2092280849Scy * week before restarting the Autokey protocol to 2093280849Scy * refresh certificates and leapseconds values. 209482505Sroberto */ 2095280849Scy if (current_time > peer->refresh) { 2096280849Scy report_event(PEVNT_RESTART, peer, 2097280849Scy "crypto refresh"); 2098280849Scy peer_clear(peer, "TIME"); 2099280849Scy return; 2100132454Sroberto } 210154359Sroberto } 2102280849Scy#endif /* AUTOKEY */ 210354359Sroberto 210454359Sroberto /* 2105182007Sroberto * The dance is complete and the flash bits have been lit. Toss 2106182007Sroberto * the packet over the fence for processing, which may light up 2107182007Sroberto * more flashers. 210854359Sroberto */ 2109280849Scy process_packet(peer, pkt, rbufp->recv_length); 2110182007Sroberto 2111182007Sroberto /* 2112280849Scy * In interleaved mode update the state variables. Also adjust the 2113280849Scy * transmit phase to avoid crossover. 2114182007Sroberto */ 2115280849Scy if (peer->flip != 0) { 2116280849Scy peer->rec = p_rec; 2117280849Scy peer->dst = rbufp->recv_time; 2118280849Scy if (peer->nextdate - current_time < (1U << min(peer->ppoll, 2119280849Scy peer->hpoll)) / 2) 2120280849Scy peer->nextdate++; 2121280849Scy else 2122280849Scy peer->nextdate--; 2123182007Sroberto } 212454359Sroberto} 212554359Sroberto 212654359Sroberto 212754359Sroberto/* 2128301247Sdelphij * process_packet - Packet Procedure, a la Section 3.4.4 of RFC-1305 2129301247Sdelphij * Or almost, at least. If we're in here we have a reasonable 2130301247Sdelphij * expectation that we will be having a long term 213154359Sroberto * relationship with this host. 213254359Sroberto */ 213382505Srobertovoid 213454359Srobertoprocess_packet( 213554359Sroberto register struct peer *peer, 2136280849Scy register struct pkt *pkt, 2137280849Scy u_int len 213854359Sroberto ) 213954359Sroberto{ 2140182007Sroberto double t34, t21; 2141132454Sroberto double p_offset, p_del, p_disp; 2142280849Scy l_fp p_rec, p_xmt, p_org, p_reftime, ci; 2143280849Scy u_char pmode, pleap, pversion, pstratum; 2144280849Scy char statstr[NTP_MAXSTRLEN]; 2145280849Scy#ifdef ASSYM 2146280849Scy int itemp; 2147280849Scy double etemp, ftemp, td; 2148280849Scy#endif /* ASSYM */ 214954359Sroberto 2150301247Sdelphij#if 0 215154359Sroberto sys_processed++; 215254359Sroberto peer->processed++; 2153301247Sdelphij#endif 215454359Sroberto p_del = FPTOD(NTOHS_FP(pkt->rootdelay)); 2155280849Scy p_offset = 0; 2156280849Scy p_disp = FPTOD(NTOHS_FP(pkt->rootdisp)); 215754359Sroberto NTOHL_FP(&pkt->reftime, &p_reftime); 2158280849Scy NTOHL_FP(&pkt->org, &p_org); 215954359Sroberto NTOHL_FP(&pkt->rec, &p_rec); 216054359Sroberto NTOHL_FP(&pkt->xmt, &p_xmt); 2161132454Sroberto pmode = PKT_MODE(pkt->li_vn_mode); 2162132454Sroberto pleap = PKT_LEAP(pkt->li_vn_mode); 2163280849Scy pversion = PKT_VERSION(pkt->li_vn_mode); 2164132454Sroberto pstratum = PKT_TO_STRATUM(pkt->stratum); 216554359Sroberto 2166301247Sdelphij /**/ 2167301247Sdelphij 2168301247Sdelphij /**/ 2169301247Sdelphij 217054359Sroberto /* 2171301247Sdelphij * Verify the server is synchronized; that is, the leap bits, 2172301247Sdelphij * stratum and root distance are valid. 2173301247Sdelphij */ 2174301247Sdelphij if ( pleap == LEAP_NOTINSYNC /* test 6 */ 2175301247Sdelphij || pstratum < sys_floor || pstratum >= sys_ceiling) 2176301247Sdelphij peer->flash |= TEST6; /* bad synch or strat */ 2177301247Sdelphij if (p_del / 2 + p_disp >= MAXDISPERSE) /* test 7 */ 2178301247Sdelphij peer->flash |= TEST7; /* bad header */ 2179301247Sdelphij 2180301247Sdelphij /* 2181301247Sdelphij * If any tests fail at this point, the packet is discarded. 2182301247Sdelphij * Note that some flashers may have already been set in the 2183301247Sdelphij * receive() routine. 2184301247Sdelphij */ 2185301247Sdelphij if (peer->flash & PKT_TEST_MASK) { 2186301247Sdelphij peer->seldisptoolarge++; 2187301247Sdelphij DPRINTF(1, ("packet: flash header %04x\n", 2188301247Sdelphij peer->flash)); 2189301247Sdelphij return; 2190301247Sdelphij } 2191301247Sdelphij 2192301247Sdelphij /**/ 2193301247Sdelphij 2194301247Sdelphij#if 1 2195301247Sdelphij sys_processed++; 2196301247Sdelphij peer->processed++; 2197301247Sdelphij#endif 2198301247Sdelphij 2199301247Sdelphij /* 2200280849Scy * Capture the header values in the client/peer association.. 220154359Sroberto */ 2202280849Scy record_raw_stats(&peer->srcadr, peer->dstadr ? 2203280849Scy &peer->dstadr->sin : NULL, 2204280849Scy &p_org, &p_rec, &p_xmt, &peer->dst, 2205280849Scy pleap, pversion, pmode, pstratum, pkt->ppoll, pkt->precision, 2206280849Scy p_del, p_disp, pkt->refid); 2207132454Sroberto peer->leap = pleap; 2208182007Sroberto peer->stratum = min(pstratum, STRATUM_UNSPEC); 2209182007Sroberto peer->pmode = pmode; 2210182007Sroberto peer->precision = pkt->precision; 2211182007Sroberto peer->rootdelay = p_del; 2212280849Scy peer->rootdisp = p_disp; 2213182007Sroberto peer->refid = pkt->refid; /* network byte order */ 2214182007Sroberto peer->reftime = p_reftime; 221582505Sroberto 221682505Sroberto /* 2217280849Scy * First, if either burst mode is armed, enable the burst. 2218280849Scy * Compute the headway for the next packet and delay if 2219280849Scy * necessary to avoid exceeding the threshold. 222082505Sroberto */ 2221280849Scy if (peer->retry > 0) { 2222280849Scy peer->retry = 0; 2223280849Scy if (peer->reach) 2224280849Scy peer->burst = min(1 << (peer->hpoll - 2225280849Scy peer->minpoll), NTP_SHIFT) - 1; 2226280849Scy else 2227280849Scy peer->burst = NTP_IBURST - 1; 2228280849Scy if (peer->burst > 0) 2229280849Scy peer->nextdate = current_time; 2230280849Scy } 2231280849Scy poll_update(peer, peer->hpoll); 2232280849Scy 2233301247Sdelphij /**/ 2234132454Sroberto 2235132454Sroberto /* 2236280849Scy * If the peer was previously unreachable, raise a trap. In any 2237280849Scy * case, mark it reachable. 2238282408Scy */ 2239280849Scy if (!peer->reach) { 2240280849Scy report_event(PEVNT_REACH, peer, NULL); 224154359Sroberto peer->timereachable = current_time; 224254359Sroberto } 224354359Sroberto peer->reach |= 1; 224454359Sroberto 224554359Sroberto /* 2246182007Sroberto * For a client/server association, calculate the clock offset, 2247182007Sroberto * roundtrip delay and dispersion. The equations are reordered 2248182007Sroberto * from the spec for more efficient use of temporaries. For a 2249182007Sroberto * broadcast association, offset the last measurement by the 2250280849Scy * computed delay during the client/server volley. Note the 2251182007Sroberto * computation of dispersion includes the system precision plus 2252182007Sroberto * that due to the frequency error since the origin time. 225354359Sroberto * 2254182007Sroberto * It is very important to respect the hazards of overflow. The 2255182007Sroberto * only permitted operation on raw timestamps is subtraction, 2256182007Sroberto * where the result is a signed quantity spanning from 68 years 2257182007Sroberto * in the past to 68 years in the future. To avoid loss of 2258182007Sroberto * precision, these calculations are done using 64-bit integer 2259182007Sroberto * arithmetic. However, the offset and delay calculations are 2260182007Sroberto * sums and differences of these first-order differences, which 2261182007Sroberto * if done using 64-bit integer arithmetic, would be valid over 2262182007Sroberto * only half that span. Since the typical first-order 2263182007Sroberto * differences are usually very small, they are converted to 64- 2264182007Sroberto * bit doubles and all remaining calculations done in floating- 2265280849Scy * double arithmetic. This preserves the accuracy while 2266280849Scy * retaining the 68-year span. 2267182007Sroberto * 2268280849Scy * There are three interleaving schemes, basic, interleaved 2269280849Scy * symmetric and interleaved broadcast. The timestamps are 2270280849Scy * idioscyncratically different. See the onwire briefing/white 2271280849Scy * paper at www.eecis.udel.edu/~mills for details. 2272280849Scy * 2273280849Scy * Interleaved symmetric mode 2274280849Scy * t1 = peer->aorg/borg, t2 = peer->rec, t3 = p_xmt, 2275280849Scy * t4 = peer->dst 227654359Sroberto */ 2277280849Scy if (peer->flip != 0) { 2278280849Scy ci = p_xmt; /* t3 - t4 */ 2279280849Scy L_SUB(&ci, &peer->dst); 2280280849Scy LFPTOD(&ci, t34); 2281280849Scy ci = p_rec; /* t2 - t1 */ 2282280849Scy if (peer->flip > 0) 2283280849Scy L_SUB(&ci, &peer->borg); 2284280849Scy else 2285280849Scy L_SUB(&ci, &peer->aorg); 2286280849Scy LFPTOD(&ci, t21); 2287280849Scy p_del = t21 - t34; 2288280849Scy p_offset = (t21 + t34) / 2.; 2289280849Scy if (p_del < 0 || p_del > 1.) { 2290280849Scy snprintf(statstr, sizeof(statstr), 2291280849Scy "t21 %.6f t34 %.6f", t21, t34); 2292280849Scy report_event(PEVNT_XERR, peer, statstr); 2293280849Scy return; 2294280849Scy } 229554359Sroberto 229654359Sroberto /* 2297280849Scy * Broadcast modes 229854359Sroberto */ 2299280849Scy } else if (peer->pmode == MODE_BROADCAST) { 2300280849Scy 2301280849Scy /* 2302280849Scy * Interleaved broadcast mode. Use interleaved timestamps. 2303280849Scy * t1 = peer->borg, t2 = p_org, t3 = p_org, t4 = aorg 2304280849Scy */ 2305282408Scy if (peer->flags & FLAG_XB) { 2306282408Scy ci = p_org; /* delay */ 2307280849Scy L_SUB(&ci, &peer->aorg); 2308280849Scy LFPTOD(&ci, t34); 2309280849Scy ci = p_org; /* t2 - t1 */ 2310280849Scy L_SUB(&ci, &peer->borg); 2311280849Scy LFPTOD(&ci, t21); 2312280849Scy peer->aorg = p_xmt; 2313280849Scy peer->borg = peer->dst; 2314280849Scy if (t34 < 0 || t34 > 1.) { 2315298695Sdelphij /* drop all if in the initial volley */ 2316298695Sdelphij if (FLAG_BC_VOL & peer->flags) 2317298695Sdelphij goto bcc_init_volley_fail; 2318280849Scy snprintf(statstr, sizeof(statstr), 2319280849Scy "offset %.6f delay %.6f", t21, t34); 2320280849Scy report_event(PEVNT_XERR, peer, statstr); 232182505Sroberto return; 2322280849Scy } 2323280849Scy p_offset = t21; 2324280849Scy peer->xleave = t34; 232554359Sroberto 2326280849Scy /* 2327280849Scy * Basic broadcast - use direct timestamps. 2328280849Scy * t3 = p_xmt, t4 = peer->dst 2329280849Scy */ 2330280849Scy } else { 2331280849Scy ci = p_xmt; /* t3 - t4 */ 2332280849Scy L_SUB(&ci, &peer->dst); 2333280849Scy LFPTOD(&ci, t34); 2334280849Scy p_offset = t34; 233554359Sroberto } 2336280849Scy 2337280849Scy /* 2338280849Scy * When calibration is complete and the clock is 2339280849Scy * synchronized, the bias is calculated as the difference 2340280849Scy * between the unicast timestamp and the broadcast 2341280849Scy * timestamp. This works for both basic and interleaved 2342280849Scy * modes. 2343298695Sdelphij * [Bug 3031] Don't keep this peer when the delay 2344298695Sdelphij * calculation gives reason to suspect clock steps. 2345298695Sdelphij * This is assumed for delays > 50ms. 2346280849Scy */ 2347280849Scy if (FLAG_BC_VOL & peer->flags) { 2348280849Scy peer->flags &= ~FLAG_BC_VOL; 2349280849Scy peer->delay = fabs(peer->offset - p_offset) * 2; 2350298695Sdelphij DPRINTF(2, ("broadcast volley: initial delay=%.6f\n", 2351298695Sdelphij peer->delay)); 2352298695Sdelphij if (peer->delay > fabs(sys_bdelay)) { 2353298695Sdelphij bcc_init_volley_fail: 2354298695Sdelphij DPRINTF(2, ("%s", "broadcast volley: initial delay exceeds limit\n")); 2355298695Sdelphij unpeer(peer); 2356298695Sdelphij return; 2357298695Sdelphij } 2358280849Scy } 2359298695Sdelphij peer->nextdate = current_time + (1u << peer->ppoll) - 2u; 236054359Sroberto p_del = peer->delay; 2361280849Scy p_offset += p_del / 2; 2362280849Scy 2363280849Scy 2364280849Scy /* 2365280849Scy * Basic mode, otherwise known as the old fashioned way. 2366280849Scy * 2367280849Scy * t1 = p_org, t2 = p_rec, t3 = p_xmt, t4 = peer->dst 2368280849Scy */ 236954359Sroberto } else { 2370280849Scy ci = p_xmt; /* t3 - t4 */ 2371280849Scy L_SUB(&ci, &peer->dst); 2372280849Scy LFPTOD(&ci, t34); 2373280849Scy ci = p_rec; /* t2 - t1 */ 2374280849Scy L_SUB(&ci, &p_org); 2375280849Scy LFPTOD(&ci, t21); 2376280849Scy p_del = fabs(t21 - t34); 2377182007Sroberto p_offset = (t21 + t34) / 2.; 237854359Sroberto } 237982505Sroberto p_del = max(p_del, LOGTOD(sys_precision)); 2380280849Scy p_disp = LOGTOD(sys_precision) + LOGTOD(peer->precision) + 2381280849Scy clock_phi * p_del; 2382280849Scy 2383280849Scy#if ASSYM 2384280849Scy /* 2385280849Scy * This code calculates the outbound and inbound data rates by 2386280849Scy * measuring the differences between timestamps at different 2387280849Scy * packet lengths. This is helpful in cases of large asymmetric 2388280849Scy * delays commonly experienced on deep space communication 2389280849Scy * links. 2390280849Scy */ 2391280849Scy if (peer->t21_last > 0 && peer->t34_bytes > 0) { 2392280849Scy itemp = peer->t21_bytes - peer->t21_last; 2393280849Scy if (itemp > 25) { 2394280849Scy etemp = t21 - peer->t21; 2395280849Scy if (fabs(etemp) > 1e-6) { 2396280849Scy ftemp = itemp / etemp; 2397280849Scy if (ftemp > 1000.) 2398280849Scy peer->r21 = ftemp; 2399280849Scy } 2400280849Scy } 2401280849Scy itemp = len - peer->t34_bytes; 2402280849Scy if (itemp > 25) { 2403280849Scy etemp = -t34 - peer->t34; 2404280849Scy if (fabs(etemp) > 1e-6) { 2405280849Scy ftemp = itemp / etemp; 2406280849Scy if (ftemp > 1000.) 2407280849Scy peer->r34 = ftemp; 2408280849Scy } 2409280849Scy } 2410280849Scy } 2411280849Scy 2412280849Scy /* 2413280849Scy * The following section compensates for different data rates on 2414280849Scy * the outbound (d21) and inbound (t34) directions. To do this, 2415280849Scy * it finds t such that r21 * t - r34 * (d - t) = 0, where d is 2416280849Scy * the roundtrip delay. Then it calculates the correction as a 2417280849Scy * fraction of d. 2418280849Scy */ 2419293423Sdelphij peer->t21 = t21; 2420280849Scy peer->t21_last = peer->t21_bytes; 2421280849Scy peer->t34 = -t34; 2422280849Scy peer->t34_bytes = len; 2423293423Sdelphij DPRINTF(2, ("packet: t21 %.9lf %d t34 %.9lf %d\n", peer->t21, 2424293423Sdelphij peer->t21_bytes, peer->t34, peer->t34_bytes)); 2425280849Scy if (peer->r21 > 0 && peer->r34 > 0 && p_del > 0) { 2426280849Scy if (peer->pmode != MODE_BROADCAST) 2427280849Scy td = (peer->r34 / (peer->r21 + peer->r34) - 2428280849Scy .5) * p_del; 2429280849Scy else 2430280849Scy td = 0; 2431280849Scy 2432280849Scy /* 2433293423Sdelphij * Unfortunately, in many cases the errors are 2434280849Scy * unacceptable, so for the present the rates are not 2435280849Scy * used. In future, we might find conditions where the 2436280849Scy * calculations are useful, so this should be considered 2437280849Scy * a work in progress. 2438280849Scy */ 2439280849Scy t21 -= td; 2440280849Scy t34 -= td; 2441293423Sdelphij DPRINTF(2, ("packet: del %.6lf r21 %.1lf r34 %.1lf %.6lf\n", 2442280849Scy p_del, peer->r21 / 1e3, peer->r34 / 1e3, 2443293423Sdelphij td)); 2444282408Scy } 2445280849Scy#endif /* ASSYM */ 2446280849Scy 2447280849Scy /* 2448280849Scy * That was awesome. Now hand off to the clock filter. 2449280849Scy */ 2450280849Scy clock_filter(peer, p_offset + peer->bias, p_del, p_disp); 2451280849Scy 2452280849Scy /* 2453280849Scy * If we are in broadcast calibrate mode, return to broadcast 2454280849Scy * client mode when the client is fit and the autokey dance is 2455280849Scy * complete. 2456280849Scy */ 2457289764Sglebius if ( (FLAG_BC_VOL & peer->flags) 2458289764Sglebius && MODE_CLIENT == peer->hmode 2459289764Sglebius && !(TEST11 & peer_unfit(peer))) { /* distance exceeded */ 2460280849Scy#ifdef AUTOKEY 2461280849Scy if (peer->flags & FLAG_SKEY) { 2462280849Scy if (!(~peer->crypto & CRYPTO_FLAG_ALL)) 2463280849Scy peer->hmode = MODE_BCLIENT; 2464280849Scy } else { 2465280849Scy peer->hmode = MODE_BCLIENT; 2466280849Scy } 2467280849Scy#else /* !AUTOKEY follows */ 2468280849Scy peer->hmode = MODE_BCLIENT; 2469280849Scy#endif /* !AUTOKEY */ 2470280849Scy } 247154359Sroberto} 247254359Sroberto 247354359Sroberto 247454359Sroberto/* 247554359Sroberto * clock_update - Called at system process update intervals. 247654359Sroberto */ 247754359Srobertostatic void 2478280849Scyclock_update( 2479280849Scy struct peer *peer /* peer structure pointer */ 2480280849Scy ) 248154359Sroberto{ 2482182007Sroberto double dtemp; 2483280849Scy l_fp now; 2484280849Scy#ifdef HAVE_LIBSCF_H 2485280849Scy char *fmri; 2486280849Scy#endif /* HAVE_LIBSCF_H */ 248754359Sroberto 248854359Sroberto /* 2489280849Scy * Update the system state variables. We do this very carefully, 2490280849Scy * as the poll interval might need to be clamped differently. 249154359Sroberto */ 2492280849Scy sys_peer = peer; 2493280849Scy sys_epoch = peer->epoch; 2494280849Scy if (sys_poll < peer->minpoll) 2495280849Scy sys_poll = peer->minpoll; 2496280849Scy if (sys_poll > peer->maxpoll) 2497280849Scy sys_poll = peer->maxpoll; 2498280849Scy poll_update(peer, sys_poll); 2499280849Scy sys_stratum = min(peer->stratum + 1, STRATUM_UNSPEC); 2500289764Sglebius if ( peer->stratum == STRATUM_REFCLOCK 2501289764Sglebius || peer->stratum == STRATUM_UNSPEC) 2502280849Scy sys_refid = peer->refid; 2503280849Scy else 2504280849Scy sys_refid = addr2refid(&peer->srcadr); 2505280849Scy /* 2506280849Scy * Root Dispersion (E) is defined (in RFC 5905) as: 2507280849Scy * 2508280849Scy * E = p.epsilon_r + p.epsilon + p.psi + PHI*(s.t - p.t) + |THETA| 2509280849Scy * 2510280849Scy * where: 2511280849Scy * p.epsilon_r is the PollProc's root dispersion 2512280849Scy * p.epsilon is the PollProc's dispersion 2513280849Scy * p.psi is the PollProc's jitter 2514280849Scy * THETA is the combined offset 2515280849Scy * 2516280849Scy * NB: Think Hard about where these numbers come from and 2517280849Scy * what they mean. When did peer->update happen? Has anything 2518280849Scy * interesting happened since then? What values are the most 2519280849Scy * defensible? Why? 2520280849Scy * 2521280849Scy * DLM thinks this equation is probably the best of all worse choices. 2522280849Scy */ 2523280849Scy dtemp = peer->rootdisp 2524280849Scy + peer->disp 2525280849Scy + sys_jitter 2526280849Scy + clock_phi * (current_time - peer->update) 2527280849Scy + fabs(sys_offset); 2528182007Sroberto 2529280849Scy if (dtemp > sys_mindisp) 2530280849Scy sys_rootdisp = dtemp; 2531280849Scy else 2532280849Scy sys_rootdisp = sys_mindisp; 2533280849Scy sys_rootdelay = peer->delay + peer->rootdelay; 2534280849Scy sys_reftime = peer->dst; 2535280849Scy 2536293423Sdelphij DPRINTF(1, ("clock_update: at %lu sample %lu associd %d\n", 2537293423Sdelphij current_time, peer->epoch, peer->associd)); 253854359Sroberto 253982505Sroberto /* 2540280849Scy * Comes now the moment of truth. Crank the clock discipline and 2541280849Scy * see what comes out. 2542280849Scy */ 2543280849Scy switch (local_clock(peer, sys_offset)) { 2544280849Scy 2545280849Scy /* 2546182007Sroberto * Clock exceeds panic threshold. Life as we know it ends. 254782505Sroberto */ 254882505Sroberto case -1: 2549280849Scy#ifdef HAVE_LIBSCF_H 2550280849Scy /* 2551280849Scy * For Solaris enter the maintenance mode. 2552280849Scy */ 2553280849Scy if ((fmri = getenv("SMF_FMRI")) != NULL) { 2554280849Scy if (smf_maintain_instance(fmri, 0) < 0) { 2555280849Scy printf("smf_maintain_instance: %s\n", 2556280849Scy scf_strerror(scf_error())); 2557280849Scy exit(1); 2558280849Scy } 2559280849Scy /* 2560280849Scy * Sleep until SMF kills us. 2561280849Scy */ 2562280849Scy for (;;) 2563280849Scy pause(); 2564280849Scy } 2565280849Scy#endif /* HAVE_LIBSCF_H */ 2566132454Sroberto exit (-1); 2567182007Sroberto /* not reached */ 256854359Sroberto 256982505Sroberto /* 257082505Sroberto * Clock was stepped. Flush all time values of all peers. 257182505Sroberto */ 2572182007Sroberto case 2: 257382505Sroberto clear_all(); 2574285169Scy set_sys_leap(LEAP_NOTINSYNC); 2575182007Sroberto sys_stratum = STRATUM_UNSPEC; 2576280849Scy memcpy(&sys_refid, "STEP", 4); 2577182007Sroberto sys_rootdelay = 0; 2578280849Scy sys_rootdisp = 0; 2579280849Scy L_CLR(&sys_reftime); 2580280849Scy sys_jitter = LOGTOD(sys_precision); 2581280849Scy leapsec_reset_frame(); 258254359Sroberto break; 258354359Sroberto 258482505Sroberto /* 2585280849Scy * Clock was slewed. Handle the leapsecond stuff. 258682505Sroberto */ 2587182007Sroberto case 1: 2588182007Sroberto 2589182007Sroberto /* 2590280849Scy * If this is the first time the clock is set, reset the 2591280849Scy * leap bits. If crypto, the timer will goose the setup 2592280849Scy * process. 2593182007Sroberto */ 2594280849Scy if (sys_leap == LEAP_NOTINSYNC) { 2595285169Scy set_sys_leap(LEAP_NOWARNING); 2596280849Scy#ifdef AUTOKEY 2597280849Scy if (crypto_flags) 2598280849Scy crypto_update(); 2599280849Scy#endif /* AUTOKEY */ 2600280849Scy /* 2601280849Scy * If our parent process is waiting for the 2602280849Scy * first clock sync, send them home satisfied. 2603280849Scy */ 2604280849Scy#ifdef HAVE_WORKING_FORK 2605280849Scy if (waitsync_fd_to_close != -1) { 2606280849Scy close(waitsync_fd_to_close); 2607280849Scy waitsync_fd_to_close = -1; 2608280849Scy DPRINTF(1, ("notified parent --wait-sync is done\n")); 2609280849Scy } 2610280849Scy#endif /* HAVE_WORKING_FORK */ 2611280849Scy 2612182007Sroberto } 2613280849Scy 2614280849Scy /* 2615280849Scy * If there is no leap second pending and the number of 2616280849Scy * survivor leap bits is greater than half the number of 2617280849Scy * survivors, try to schedule a leap for the end of the 2618280849Scy * current month. (This only works if no leap second for 2619280849Scy * that range is in the table, so doing this more than 2620280849Scy * once is mostly harmless.) 2621280849Scy */ 2622280849Scy if (leapsec == LSPROX_NOWARN) { 2623289764Sglebius if ( leap_vote_ins > leap_vote_del 2624280849Scy && leap_vote_ins > sys_survivors / 2) { 2625280849Scy get_systime(&now); 2626280849Scy leapsec_add_dyn(TRUE, now.l_ui, NULL); 2627280849Scy } 2628289764Sglebius if ( leap_vote_del > leap_vote_ins 2629280849Scy && leap_vote_del > sys_survivors / 2) { 2630280849Scy get_systime(&now); 2631280849Scy leapsec_add_dyn(FALSE, now.l_ui, NULL); 2632280849Scy } 2633132454Sroberto } 2634182007Sroberto break; 2635280849Scy 2636182007Sroberto /* 2637182007Sroberto * Popcorn spike or step threshold exceeded. Pretend it never 2638182007Sroberto * happened. 2639182007Sroberto */ 2640182007Sroberto default: 2641182007Sroberto break; 264254359Sroberto } 264354359Sroberto} 264454359Sroberto 264554359Sroberto 264654359Sroberto/* 264782505Sroberto * poll_update - update peer poll interval 264854359Sroberto */ 264954359Srobertovoid 265054359Srobertopoll_update( 2651280849Scy struct peer *peer, /* peer structure pointer */ 2652280849Scy u_char mpoll 265354359Sroberto ) 265454359Sroberto{ 2655280849Scy u_long next, utemp; 2656280849Scy u_char hpoll; 265754359Sroberto 265854359Sroberto /* 2659182007Sroberto * This routine figures out when the next poll should be sent. 2660280849Scy * That turns out to be wickedly complicated. One problem is 2661280849Scy * that sometimes the time for the next poll is in the past when 2662280849Scy * the poll interval is reduced. We watch out for races here 2663280849Scy * between the receive process and the poll process. 2664182007Sroberto * 2665280849Scy * Clamp the poll interval between minpoll and maxpoll. 266654359Sroberto */ 2667280849Scy hpoll = max(min(peer->maxpoll, mpoll), peer->minpoll); 2668182007Sroberto 2669280849Scy#ifdef AUTOKEY 2670182007Sroberto /* 2671280849Scy * If during the crypto protocol the poll interval has changed, 2672280849Scy * the lifetimes in the key list are probably bogus. Purge the 2673280849Scy * the key list and regenerate it later. 2674182007Sroberto */ 2675280849Scy if ((peer->flags & FLAG_SKEY) && hpoll != peer->hpoll) 2676182007Sroberto key_expire(peer); 2677280849Scy#endif /* AUTOKEY */ 2678182007Sroberto peer->hpoll = hpoll; 267982505Sroberto 268082505Sroberto /* 2681280849Scy * There are three variables important for poll scheduling, the 2682280849Scy * current time (current_time), next scheduled time (nextdate) 2683280849Scy * and the earliest time (utemp). The earliest time is 2 s 2684280849Scy * seconds, but could be more due to rate management. When 2685280849Scy * sending in a burst, use the earliest time. When not in a 2686280849Scy * burst but with a reply pending, send at the earliest time 2687280849Scy * unless the next scheduled time has not advanced. This can 2688280849Scy * only happen if multiple replies are pending in the same 2689280849Scy * response interval. Otherwise, send at the later of the next 2690280849Scy * scheduled time and the earliest time. 2691280849Scy * 2692280849Scy * Now we figure out if there is an override. If a burst is in 2693280849Scy * progress and we get called from the receive process, just 2694280849Scy * slink away. If called from the poll process, delay 1 s for a 2695280849Scy * reference clock, otherwise 2 s. 269682505Sroberto */ 2697280849Scy utemp = current_time + max(peer->throttle - (NTP_SHIFT - 1) * 2698280849Scy (1 << peer->minpoll), ntp_minpkt); 269954359Sroberto if (peer->burst > 0) { 2700280849Scy if (peer->nextdate > current_time) 270154359Sroberto return; 270282505Sroberto#ifdef REFCLOCK 270382505Sroberto else if (peer->flags & FLAG_REFCLOCK) 2704280849Scy peer->nextdate = current_time + RESP_DELAY; 2705182007Sroberto#endif /* REFCLOCK */ 270654359Sroberto else 2707280849Scy peer->nextdate = utemp; 2708280849Scy 2709280849Scy#ifdef AUTOKEY 2710182007Sroberto /* 2711280849Scy * If a burst is not in progress and a crypto response message 2712280849Scy * is pending, delay 2 s, but only if this is a new interval. 2713182007Sroberto */ 2714280849Scy } else if (peer->cmmd != NULL) { 2715280849Scy if (peer->nextdate > current_time) { 2716280849Scy if (peer->nextdate + ntp_minpkt != utemp) 2717280849Scy peer->nextdate = utemp; 2718280849Scy } else { 2719280849Scy peer->nextdate = utemp; 2720280849Scy } 2721280849Scy#endif /* AUTOKEY */ 2722182007Sroberto 272382505Sroberto /* 2724280849Scy * The ordinary case. If a retry, use minpoll; if unreachable, 2725280849Scy * use host poll; otherwise, use the minimum of host and peer 2726280849Scy * polls; In other words, oversampling is okay but 2727280849Scy * understampling is evil. Use the maximum of this value and the 2728280849Scy * headway. If the average headway is greater than the headway 2729280849Scy * threshold, increase the headway by the minimum interval. 273082505Sroberto */ 2731280849Scy } else { 2732280849Scy if (peer->retry > 0) 2733280849Scy hpoll = peer->minpoll; 2734280849Scy else if (!(peer->reach)) 2735280849Scy hpoll = peer->hpoll; 2736280849Scy else 2737280849Scy hpoll = min(peer->ppoll, peer->hpoll); 2738280849Scy#ifdef REFCLOCK 2739280849Scy if (peer->flags & FLAG_REFCLOCK) 2740280849Scy next = 1 << hpoll; 2741280849Scy else 2742280849Scy#endif /* REFCLOCK */ 2743280849Scy next = ((0x1000UL | (ntp_random() & 0x0ff)) << 2744280849Scy hpoll) >> 12; 2745280849Scy next += peer->outdate; 2746280849Scy if (next > utemp) 2747280849Scy peer->nextdate = next; 2748280849Scy else 2749280849Scy peer->nextdate = utemp; 2750280849Scy if (peer->throttle > (1 << peer->minpoll)) 2751280849Scy peer->nextdate += ntp_minpkt; 2752280849Scy } 2753280849Scy DPRINTF(2, ("poll_update: at %lu %s poll %d burst %d retry %d head %d early %lu next %lu\n", 2754280849Scy current_time, ntoa(&peer->srcadr), peer->hpoll, 2755280849Scy peer->burst, peer->retry, peer->throttle, 2756280849Scy utemp - current_time, peer->nextdate - 2757280849Scy current_time)); 275854359Sroberto} 275954359Sroberto 2760280849Scy 276154359Sroberto/* 2762280849Scy * peer_clear - clear peer filter registers. See Section 3.4.8 of the 2763280849Scy * spec. 276454359Sroberto */ 276554359Srobertovoid 2766280849Scypeer_clear( 2767280849Scy struct peer *peer, /* peer structure */ 2768280849Scy const char *ident /* tally lights */ 2769280849Scy ) 277054359Sroberto{ 2771280849Scy u_char u; 2772309007Sdelphij l_fp bxmt = peer->bxmt; /* bcast clients retain this! */ 2773280849Scy 2774280849Scy#ifdef AUTOKEY 277582505Sroberto /* 277682505Sroberto * If cryptographic credentials have been acquired, toss them to 277782505Sroberto * Valhalla. Note that autokeys are ephemeral, in that they are 277882505Sroberto * tossed immediately upon use. Therefore, the keylist can be 277982505Sroberto * purged anytime without needing to preserve random keys. Note 278082505Sroberto * that, if the peer is purged, the cryptographic variables are 278182505Sroberto * purged, too. This makes it much harder to sneak in some 278282505Sroberto * unauthenticated data in the clock filter. 278382505Sroberto */ 2784280849Scy key_expire(peer); 2785132454Sroberto if (peer->iffval != NULL) 2786132454Sroberto BN_free(peer->iffval); 2787132454Sroberto value_free(&peer->cookval); 2788132454Sroberto value_free(&peer->recval); 2789280849Scy value_free(&peer->encrypt); 2790280849Scy value_free(&peer->sndval); 2791280849Scy if (peer->cmmd != NULL) 2792182007Sroberto free(peer->cmmd); 2793280849Scy if (peer->subject != NULL) 2794280849Scy free(peer->subject); 2795280849Scy if (peer->issuer != NULL) 2796280849Scy free(peer->issuer); 2797280849Scy#endif /* AUTOKEY */ 2798182007Sroberto 279982505Sroberto /* 2800280849Scy * Clear all values, including the optional crypto values above. 280182505Sroberto */ 2802280849Scy memset(CLEAR_TO_ZERO(peer), 0, LEN_CLEAR_TO_ZERO(peer)); 280382505Sroberto peer->ppoll = peer->maxpoll; 2804182007Sroberto peer->hpoll = peer->minpoll; 2805182007Sroberto peer->disp = MAXDISPERSE; 2806280849Scy peer->flash = peer_unfit(peer); 2807182007Sroberto peer->jitter = LOGTOD(sys_precision); 2808280849Scy 2809309007Sdelphij /* Don't throw away our broadcast replay protection */ 2810309007Sdelphij if (peer->hmode == MODE_BCLIENT) 2811309007Sdelphij peer->bxmt = bxmt; 2812309007Sdelphij 2813280849Scy /* 2814280849Scy * If interleave mode, initialize the alternate origin switch. 2815280849Scy */ 2816280849Scy if (peer->flags & FLAG_XLEAVE) 2817280849Scy peer->flip = 1; 2818280849Scy for (u = 0; u < NTP_SHIFT; u++) { 2819280849Scy peer->filter_order[u] = u; 2820280849Scy peer->filter_disp[u] = MAXDISPERSE; 2821182007Sroberto } 282282505Sroberto#ifdef REFCLOCK 282382505Sroberto if (!(peer->flags & FLAG_REFCLOCK)) { 2824280849Scy#endif 282582505Sroberto peer->leap = LEAP_NOTINSYNC; 282682505Sroberto peer->stratum = STRATUM_UNSPEC; 2827132454Sroberto memcpy(&peer->refid, ident, 4); 2828280849Scy#ifdef REFCLOCK 282982505Sroberto } 2830280849Scy#endif 283154359Sroberto 283254359Sroberto /* 2833182007Sroberto * During initialization use the association count to spread out 2834280849Scy * the polls at one-second intervals. Passive associations' 2835280849Scy * first poll is delayed by the "discard minimum" to avoid rate 2836280849Scy * limiting. Other post-startup new or cleared associations 2837280849Scy * randomize the first poll over the minimum poll interval to 2838280849Scy * avoid implosion. 283954359Sroberto */ 2840132454Sroberto peer->nextdate = peer->update = peer->outdate = current_time; 2841280849Scy if (initializing) { 2842182007Sroberto peer->nextdate += peer_associations; 2843280849Scy } else if (MODE_PASSIVE == peer->hmode) { 2844280849Scy peer->nextdate += ntp_minpkt; 2845280849Scy } else { 2846280849Scy peer->nextdate += ntp_random() % peer->minpoll; 2847280849Scy } 2848280849Scy#ifdef AUTOKEY 2849280849Scy peer->refresh = current_time + (1 << NTP_REFRESH); 2850280849Scy#endif /* AUTOKEY */ 2851293423Sdelphij DPRINTF(1, ("peer_clear: at %ld next %ld associd %d refid %s\n", 2852280849Scy current_time, peer->nextdate, peer->associd, 2853293423Sdelphij ident)); 285454359Sroberto} 285554359Sroberto 285654359Sroberto 285754359Sroberto/* 285854359Sroberto * clock_filter - add incoming clock sample to filter register and run 285954359Sroberto * the filter procedure to find the best sample. 286054359Sroberto */ 286154359Srobertovoid 286254359Srobertoclock_filter( 2863132454Sroberto struct peer *peer, /* peer structure pointer */ 2864132454Sroberto double sample_offset, /* clock offset */ 2865132454Sroberto double sample_delay, /* roundtrip delay */ 2866132454Sroberto double sample_disp /* dispersion */ 286754359Sroberto ) 286854359Sroberto{ 2869132454Sroberto double dst[NTP_SHIFT]; /* distance vector */ 2870132454Sroberto int ord[NTP_SHIFT]; /* index vector */ 2871132454Sroberto int i, j, k, m; 2872182007Sroberto double dtemp, etemp; 2873280849Scy char tbuf[80]; 287454359Sroberto 287554359Sroberto /* 2876280849Scy * A sample consists of the offset, delay, dispersion and epoch 2877280849Scy * of arrival. The offset and delay are determined by the on- 2878280849Scy * wire protocol. The dispersion grows from the last outbound 2879280849Scy * packet to the arrival of this one increased by the sum of the 2880280849Scy * peer precision and the system precision as required by the 2881280849Scy * error budget. First, shift the new arrival into the shift 2882280849Scy * register discarding the oldest one. 288354359Sroberto */ 288454359Sroberto j = peer->filter_nextpt; 288582505Sroberto peer->filter_offset[j] = sample_offset; 2886280849Scy peer->filter_delay[j] = sample_delay; 2887182007Sroberto peer->filter_disp[j] = sample_disp; 2888182007Sroberto peer->filter_epoch[j] = current_time; 2889182007Sroberto j = (j + 1) % NTP_SHIFT; 2890182007Sroberto peer->filter_nextpt = j; 289154359Sroberto 289254359Sroberto /* 289382505Sroberto * Update dispersions since the last update and at the same 2894280849Scy * time initialize the distance and index lists. Since samples 2895280849Scy * become increasingly uncorrelated beyond the Allan intercept, 2896280849Scy * only under exceptional cases will an older sample be used. 2897280849Scy * Therefore, the distance list uses a compound metric. If the 2898280849Scy * dispersion is greater than the maximum dispersion, clamp the 2899280849Scy * distance at that value. If the time since the last update is 2900280849Scy * less than the Allan intercept use the delay; otherwise, use 2901280849Scy * the sum of the delay and dispersion. 290254359Sroberto */ 290382505Sroberto dtemp = clock_phi * (current_time - peer->update); 290482505Sroberto peer->update = current_time; 290582505Sroberto for (i = NTP_SHIFT - 1; i >= 0; i--) { 2906132454Sroberto if (i != 0) 290782505Sroberto peer->filter_disp[j] += dtemp; 2908282408Scy if (peer->filter_disp[j] >= MAXDISPERSE) { 2909132454Sroberto peer->filter_disp[j] = MAXDISPERSE; 291082505Sroberto dst[i] = MAXDISPERSE; 2911280849Scy } else if (peer->update - peer->filter_epoch[j] > 2912280849Scy (u_long)ULOGTOD(allan_xpt)) { 2913280849Scy dst[i] = peer->filter_delay[j] + 2914280849Scy peer->filter_disp[j]; 2915280849Scy } else { 2916132454Sroberto dst[i] = peer->filter_delay[j]; 2917280849Scy } 291882505Sroberto ord[i] = j; 2919280849Scy j = (j + 1) % NTP_SHIFT; 292082505Sroberto } 292154359Sroberto 2922280849Scy /* 2923282408Scy * If the clock has stabilized, sort the samples by distance. 292454359Sroberto */ 2925280849Scy if (freq_cnt == 0) { 2926182007Sroberto for (i = 1; i < NTP_SHIFT; i++) { 2927182007Sroberto for (j = 0; j < i; j++) { 2928280849Scy if (dst[j] > dst[i]) { 2929182007Sroberto k = ord[j]; 2930182007Sroberto ord[j] = ord[i]; 2931182007Sroberto ord[i] = k; 2932182007Sroberto etemp = dst[j]; 2933182007Sroberto dst[j] = dst[i]; 2934182007Sroberto dst[i] = etemp; 2935182007Sroberto } 293654359Sroberto } 293754359Sroberto } 293882505Sroberto } 293982505Sroberto 294082505Sroberto /* 294182505Sroberto * Copy the index list to the association structure so ntpq 2942280849Scy * can see it later. Prune the distance list to leave only 2943280849Scy * samples less than the maximum dispersion, which disfavors 2944280849Scy * uncorrelated samples older than the Allan intercept. To 2945280849Scy * further improve the jitter estimate, of the remainder leave 2946280849Scy * only samples less than the maximum distance, but keep at 2947280849Scy * least two samples for jitter calculation. 294882505Sroberto */ 294982505Sroberto m = 0; 295082505Sroberto for (i = 0; i < NTP_SHIFT; i++) { 2951132454Sroberto peer->filter_order[i] = (u_char) ord[i]; 2952289764Sglebius if ( dst[i] >= MAXDISPERSE 2953289764Sglebius || (m >= 2 && dst[i] >= sys_maxdist)) 295482505Sroberto continue; 295582505Sroberto m++; 295682505Sroberto } 2957282408Scy 295854359Sroberto /* 2959182007Sroberto * Compute the dispersion and jitter. The dispersion is weighted 2960182007Sroberto * exponentially by NTP_FWEIGHT (0.5) so it is normalized close 2961182007Sroberto * to 1.0. The jitter is the RMS differences relative to the 2962280849Scy * lowest delay sample. 296354359Sroberto */ 2964182007Sroberto peer->disp = peer->jitter = 0; 296582505Sroberto k = ord[0]; 296654359Sroberto for (i = NTP_SHIFT - 1; i >= 0; i--) { 296782505Sroberto j = ord[i]; 296882505Sroberto peer->disp = NTP_FWEIGHT * (peer->disp + 296982505Sroberto peer->filter_disp[j]); 297082505Sroberto if (i < m) 2971182007Sroberto peer->jitter += DIFF(peer->filter_offset[j], 297282505Sroberto peer->filter_offset[k]); 297354359Sroberto } 297454359Sroberto 297554359Sroberto /* 297682505Sroberto * If no acceptable samples remain in the shift register, 297782505Sroberto * quietly tiptoe home leaving only the dispersion. Otherwise, 2978182007Sroberto * save the offset, delay and jitter. Note the jitter must not 2979182007Sroberto * be less than the precision. 298082505Sroberto */ 2981280849Scy if (m == 0) { 2982280849Scy clock_select(); 298382505Sroberto return; 2984280849Scy } 2985132454Sroberto etemp = fabs(peer->offset - peer->filter_offset[k]); 298682505Sroberto peer->offset = peer->filter_offset[k]; 298782505Sroberto peer->delay = peer->filter_delay[k]; 298882505Sroberto if (m > 1) 2989182007Sroberto peer->jitter /= m - 1; 2990182007Sroberto peer->jitter = max(SQRT(peer->jitter), LOGTOD(sys_precision)); 299182505Sroberto 299282505Sroberto /* 2993280849Scy * If the the new sample and the current sample are both valid 2994280849Scy * and the difference between their offsets exceeds CLOCK_SGATE 2995280849Scy * (3) times the jitter and the interval between them is less 2996280849Scy * than twice the host poll interval, consider the new sample 2997280849Scy * a popcorn spike and ignore it. 299854359Sroberto */ 2999289764Sglebius if ( peer->disp < sys_maxdist 3000289764Sglebius && peer->filter_disp[k] < sys_maxdist 3001289764Sglebius && etemp > CLOCK_SGATE * peer->jitter 3002289764Sglebius && peer->filter_epoch[k] - peer->epoch 3003289764Sglebius < 2. * ULOGTOD(peer->hpoll)) { 3004280849Scy snprintf(tbuf, sizeof(tbuf), "%.6f s", etemp); 3005280849Scy report_event(PEVNT_POPCORN, peer, tbuf); 300654359Sroberto return; 300754359Sroberto } 300854359Sroberto 300954359Sroberto /* 3010280849Scy * A new minimum sample is useful only if it is later than the 3011280849Scy * last one used. In this design the maximum lifetime of any 3012280849Scy * sample is not greater than eight times the poll interval, so 3013280849Scy * the maximum interval between minimum samples is eight 3014280849Scy * packets. 301554359Sroberto */ 3016280849Scy if (peer->filter_epoch[k] <= peer->epoch) { 3017293423Sdelphij DPRINTF(2, ("clock_filter: old sample %lu\n", current_time - 3018293423Sdelphij peer->filter_epoch[k])); 301954359Sroberto return; 302054359Sroberto } 3021280849Scy peer->epoch = peer->filter_epoch[k]; 302282505Sroberto 302382505Sroberto /* 302482505Sroberto * The mitigated sample statistics are saved for later 3025280849Scy * processing. If not synchronized or not in a burst, tickle the 3026280849Scy * clock select algorithm. 302782505Sroberto */ 3028280849Scy record_peer_stats(&peer->srcadr, ctlpeerstatus(peer), 3029280849Scy peer->offset, peer->delay, peer->disp, peer->jitter); 3030293423Sdelphij DPRINTF(1, ("clock_filter: n %d off %.6f del %.6f dsp %.6f jit %.6f\n", 303182505Sroberto m, peer->offset, peer->delay, peer->disp, 3032293423Sdelphij peer->jitter)); 3033182007Sroberto if (peer->burst == 0 || sys_leap == LEAP_NOTINSYNC) 3034182007Sroberto clock_select(); 303554359Sroberto} 303654359Sroberto 303754359Sroberto 303854359Sroberto/* 303954359Sroberto * clock_select - find the pick-of-the-litter clock 3040132454Sroberto * 3041280849Scy * LOCKCLOCK: (1) If the local clock is the prefer peer, it will always 3042280849Scy * be enabled, even if declared falseticker, (2) only the prefer peer 3043280849Scy * can be selected as the system peer, (3) if the external source is 3044280849Scy * down, the system leap bits are set to 11 and the stratum set to 3045280849Scy * infinity. 304654359Sroberto */ 304754359Srobertovoid 304854359Srobertoclock_select(void) 304954359Sroberto{ 3050132454Sroberto struct peer *peer; 3051132454Sroberto int i, j, k, n; 3052280849Scy int nlist, nl2; 3053280849Scy int allow; 3054280849Scy int speer; 3055182007Sroberto double d, e, f, g; 3056132454Sroberto double high, low; 3057280849Scy double speermet; 3058280849Scy double orphmet = 2.0 * U_INT32_MAX; /* 2x is greater than */ 3059280849Scy struct endpoint endp; 306054359Sroberto struct peer *osys_peer; 3061280849Scy struct peer *sys_prefer = NULL; /* prefer peer */ 3062280849Scy struct peer *typesystem = NULL; 3063280849Scy struct peer *typeorphan = NULL; 3064280849Scy#ifdef REFCLOCK 306582505Sroberto struct peer *typeacts = NULL; 306682505Sroberto struct peer *typelocal = NULL; 3067280849Scy struct peer *typepps = NULL; 3068280849Scy#endif /* REFCLOCK */ 306954359Sroberto static struct endpoint *endpoint = NULL; 307082505Sroberto static int *indx = NULL; 3071280849Scy static peer_select *peers = NULL; 307254359Sroberto static u_int endpoint_size = 0; 3073280849Scy static u_int peers_size = 0; 307482505Sroberto static u_int indx_size = 0; 3075280849Scy size_t octets; 307654359Sroberto 307754359Sroberto /* 307882505Sroberto * Initialize and create endpoint, index and peer lists big 307982505Sroberto * enough to handle all associations. 308054359Sroberto */ 308182505Sroberto osys_peer = sys_peer; 3082132454Sroberto sys_survivors = 0; 3083132454Sroberto#ifdef LOCKCLOCK 3084285169Scy set_sys_leap(LEAP_NOTINSYNC); 3085132454Sroberto sys_stratum = STRATUM_UNSPEC; 3086132454Sroberto memcpy(&sys_refid, "DOWN", 4); 3087132454Sroberto#endif /* LOCKCLOCK */ 308854359Sroberto 308954359Sroberto /* 3090280849Scy * Allocate dynamic space depending on the number of 3091280849Scy * associations. 3092280849Scy */ 3093280849Scy nlist = 1; 3094280849Scy for (peer = peer_list; peer != NULL; peer = peer->p_link) 3095280849Scy nlist++; 3096280849Scy endpoint_size = ALIGNED_SIZE(nlist * 2 * sizeof(*endpoint)); 3097280849Scy peers_size = ALIGNED_SIZE(nlist * sizeof(*peers)); 3098280849Scy indx_size = ALIGNED_SIZE(nlist * 2 * sizeof(*indx)); 3099280849Scy octets = endpoint_size + peers_size + indx_size; 3100280849Scy endpoint = erealloc(endpoint, octets); 3101280849Scy peers = INC_ALIGNED_PTR(endpoint, endpoint_size); 3102280849Scy indx = INC_ALIGNED_PTR(peers, peers_size); 3103280849Scy 3104280849Scy /* 310582505Sroberto * Initially, we populate the island with all the rifraff peers 310682505Sroberto * that happen to be lying around. Those with seriously 310782505Sroberto * defective clocks are immediately booted off the island. Then, 310882505Sroberto * the falsetickers are culled and put to sea. The truechimers 310982505Sroberto * remaining are subject to repeated rounds where the most 311082505Sroberto * unpopular at each round is kicked off. When the population 3111132454Sroberto * has dwindled to sys_minclock, the survivors split a million 3112132454Sroberto * bucks and collectively crank the chimes. 311354359Sroberto */ 3114280849Scy nlist = nl2 = 0; /* none yet */ 3115280849Scy for (peer = peer_list; peer != NULL; peer = peer->p_link) { 3116280849Scy peer->new_status = CTL_PST_SEL_REJECT; 311754359Sroberto 3118280849Scy /* 3119280849Scy * Leave the island immediately if the peer is 3120280849Scy * unfit to synchronize. 3121280849Scy */ 3122309007Sdelphij if (peer_unfit(peer)) { 3123280849Scy continue; 3124309007Sdelphij } 312582505Sroberto 3126280849Scy /* 3127280849Scy * If this peer is an orphan parent, elect the 3128280849Scy * one with the lowest metric defined as the 3129280849Scy * IPv4 address or the first 64 bits of the 3130280849Scy * hashed IPv6 address. To ensure convergence 3131280849Scy * on the same selected orphan, consider as 3132280849Scy * well that this system may have the lowest 3133280849Scy * metric and be the orphan parent. If this 3134280849Scy * system wins, sys_peer will be NULL to trigger 3135280849Scy * orphan mode in timer(). 3136280849Scy */ 3137280849Scy if (peer->stratum == sys_orphan) { 3138280849Scy u_int32 localmet; 3139280849Scy u_int32 peermet; 314054359Sroberto 3141280849Scy if (peer->dstadr != NULL) 3142280849Scy localmet = ntohl(peer->dstadr->addr_refid); 3143280849Scy else 3144280849Scy localmet = U_INT32_MAX; 3145280849Scy peermet = ntohl(addr2refid(&peer->srcadr)); 3146280849Scy if (peermet < localmet && peermet < orphmet) { 3147280849Scy typeorphan = peer; 3148280849Scy orphmet = peermet; 314954359Sroberto } 3150280849Scy continue; 3151280849Scy } 315254359Sroberto 3153280849Scy /* 3154280849Scy * If this peer could have the orphan parent 3155280849Scy * as a synchronization ancestor, exclude it 3156282408Scy * from selection to avoid forming a 3157280849Scy * synchronization loop within the orphan mesh, 3158282408Scy * triggering stratum climb to infinity 3159280849Scy * instability. Peers at stratum higher than 3160280849Scy * the orphan stratum could have the orphan 3161280849Scy * parent in ancestry so are excluded. 3162280849Scy * See http://bugs.ntp.org/2050 3163280849Scy */ 3164309007Sdelphij if (peer->stratum > sys_orphan) { 3165280849Scy continue; 3166309007Sdelphij } 3167280849Scy#ifdef REFCLOCK 3168280849Scy /* 3169280849Scy * The following are special cases. We deal 3170280849Scy * with them later. 3171280849Scy */ 3172280849Scy if (!(peer->flags & FLAG_PREFER)) { 3173280849Scy switch (peer->refclktype) { 3174280849Scy case REFCLK_LOCALCLOCK: 3175289764Sglebius if ( current_time > orphwait 3176289764Sglebius && typelocal == NULL) 3177280849Scy typelocal = peer; 3178280849Scy continue; 3179182007Sroberto 3180280849Scy case REFCLK_ACTS: 3181289764Sglebius if ( current_time > orphwait 3182289764Sglebius && typeacts == NULL) 3183280849Scy typeacts = peer; 3184280849Scy continue; 318554359Sroberto } 3186280849Scy } 3187280849Scy#endif /* REFCLOCK */ 318854359Sroberto 3189280849Scy /* 3190280849Scy * If we get this far, the peer can stay on the 3191280849Scy * island, but does not yet have the immunity 3192280849Scy * idol. 3193280849Scy */ 3194280849Scy peer->new_status = CTL_PST_SEL_SANE; 3195280849Scy f = root_distance(peer); 3196280849Scy peers[nlist].peer = peer; 3197280849Scy peers[nlist].error = peer->jitter; 3198280849Scy peers[nlist].synch = f; 3199280849Scy nlist++; 3200182007Sroberto 3201280849Scy /* 3202280849Scy * Insert each interval endpoint on the unsorted 3203280849Scy * endpoint[] list. 3204280849Scy */ 3205280849Scy e = peer->offset; 3206280849Scy endpoint[nl2].type = -1; /* lower end */ 3207280849Scy endpoint[nl2].val = e - f; 3208280849Scy nl2++; 3209280849Scy endpoint[nl2].type = 1; /* upper end */ 3210280849Scy endpoint[nl2].val = e + f; 3211280849Scy nl2++; 3212280849Scy } 3213280849Scy /* 3214280849Scy * Construct sorted indx[] of endpoint[] indexes ordered by 3215280849Scy * offset. 3216280849Scy */ 3217280849Scy for (i = 0; i < nl2; i++) 3218280849Scy indx[i] = i; 3219280849Scy for (i = 0; i < nl2; i++) { 3220280849Scy endp = endpoint[indx[i]]; 3221280849Scy e = endp.val; 3222280849Scy k = i; 3223280849Scy for (j = i + 1; j < nl2; j++) { 3224280849Scy endp = endpoint[indx[j]]; 3225280849Scy if (endp.val < e) { 3226280849Scy e = endp.val; 3227280849Scy k = j; 322854359Sroberto } 322954359Sroberto } 3230280849Scy if (k != i) { 3231280849Scy j = indx[k]; 3232280849Scy indx[k] = indx[i]; 3233280849Scy indx[i] = j; 3234280849Scy } 323554359Sroberto } 3236280849Scy for (i = 0; i < nl2; i++) 3237280849Scy DPRINTF(3, ("select: endpoint %2d %.6f\n", 3238280849Scy endpoint[indx[i]].type, endpoint[indx[i]].val)); 3239280849Scy 3240132454Sroberto /* 3241132454Sroberto * This is the actual algorithm that cleaves the truechimers 3242132454Sroberto * from the falsetickers. The original algorithm was described 3243132454Sroberto * in Keith Marzullo's dissertation, but has been modified for 3244132454Sroberto * better accuracy. 3245132454Sroberto * 3246132454Sroberto * Briefly put, we first assume there are no falsetickers, then 3247132454Sroberto * scan the candidate list first from the low end upwards and 3248132454Sroberto * then from the high end downwards. The scans stop when the 3249132454Sroberto * number of intersections equals the number of candidates less 3250132454Sroberto * the number of falsetickers. If this doesn't happen for a 3251132454Sroberto * given number of falsetickers, we bump the number of 3252132454Sroberto * falsetickers and try again. If the number of falsetickers 3253132454Sroberto * becomes equal to or greater than half the number of 3254132454Sroberto * candidates, the Albanians have won the Byzantine wars and 3255132454Sroberto * correct synchronization is not possible. 3256132454Sroberto * 3257132454Sroberto * Here, nlist is the number of candidates and allow is the 3258182007Sroberto * number of falsetickers. Upon exit, the truechimers are the 3259280849Scy * survivors with offsets not less than low and not greater than 3260182007Sroberto * high. There may be none of them. 3261132454Sroberto */ 3262132454Sroberto low = 1e9; 3263132454Sroberto high = -1e9; 3264132454Sroberto for (allow = 0; 2 * allow < nlist; allow++) { 3265132454Sroberto 3266132454Sroberto /* 3267282408Scy * Bound the interval (low, high) as the smallest 3268280849Scy * interval containing points from the most sources. 3269132454Sroberto */ 3270132454Sroberto n = 0; 3271280849Scy for (i = 0; i < nl2; i++) { 3272132454Sroberto low = endpoint[indx[i]].val; 3273132454Sroberto n -= endpoint[indx[i]].type; 3274132454Sroberto if (n >= nlist - allow) 327554359Sroberto break; 327654359Sroberto } 3277132454Sroberto n = 0; 3278280849Scy for (j = nl2 - 1; j >= 0; j--) { 3279132454Sroberto high = endpoint[indx[j]].val; 328082505Sroberto n += endpoint[indx[j]].type; 3281132454Sroberto if (n >= nlist - allow) 328254359Sroberto break; 328354359Sroberto } 3284132454Sroberto 3285132454Sroberto /* 3286132454Sroberto * If an interval containing truechimers is found, stop. 3287132454Sroberto * If not, increase the number of falsetickers and go 3288132454Sroberto * around again. 3289132454Sroberto */ 3290132454Sroberto if (high > low) 329154359Sroberto break; 329254359Sroberto } 329354359Sroberto 329454359Sroberto /* 3295280849Scy * Clustering algorithm. Whittle candidate list of falsetickers, 3296280849Scy * who leave the island immediately. The TRUE peer is always a 3297182007Sroberto * truechimer. We must leave at least one peer to collect the 3298280849Scy * million bucks. 3299280849Scy * 3300280849Scy * We assert the correct time is contained in the interval, but 3301280849Scy * the best offset estimate for the interval might not be 3302280849Scy * contained in the interval. For this purpose, a truechimer is 3303282408Scy * defined as the midpoint of an interval that overlaps the 3304280849Scy * intersection interval. 3305182007Sroberto */ 3306182007Sroberto j = 0; 3307182007Sroberto for (i = 0; i < nlist; i++) { 3308280849Scy double h; 3309280849Scy 3310280849Scy peer = peers[i].peer; 3311280849Scy h = peers[i].synch; 3312289764Sglebius if (( high <= low 3313289764Sglebius || peer->offset + h < low 3314289764Sglebius || peer->offset - h > high 3315289764Sglebius ) && !(peer->flags & FLAG_TRUE)) 3316182007Sroberto continue; 3317182007Sroberto 3318280849Scy#ifdef REFCLOCK 3319182007Sroberto /* 3320280849Scy * Eligible PPS peers must survive the intersection 3321280849Scy * algorithm. Use the first one found, but don't 3322280849Scy * include any of them in the cluster population. 3323182007Sroberto */ 3324280849Scy if (peer->flags & FLAG_PPS) { 3325282408Scy if (typepps == NULL) 3326280849Scy typepps = peer; 3327282408Scy if (!(peer->flags & FLAG_TSTAMP_PPS)) 3328282408Scy continue; 3329182007Sroberto } 3330280849Scy#endif /* REFCLOCK */ 3331182007Sroberto 3332280849Scy if (j != i) 3333280849Scy peers[j] = peers[i]; 3334182007Sroberto j++; 3335182007Sroberto } 3336182007Sroberto nlist = j; 3337182007Sroberto 3338182007Sroberto /* 3339282408Scy * If no survivors remain at this point, check if the modem 3340280849Scy * driver, local driver or orphan parent in that order. If so, 3341280849Scy * nominate the first one found as the only survivor. 3342280849Scy * Otherwise, give up and leave the island to the rats. 334354359Sroberto */ 3344182007Sroberto if (nlist == 0) { 3345280849Scy peers[0].error = 0; 3346280849Scy peers[0].synch = sys_mindisp; 3347280849Scy#ifdef REFCLOCK 3348280849Scy if (typeacts != NULL) { 3349280849Scy peers[0].peer = typeacts; 335054359Sroberto nlist = 1; 3351280849Scy } else if (typelocal != NULL) { 3352280849Scy peers[0].peer = typelocal; 335354359Sroberto nlist = 1; 3354280849Scy } else 3355280849Scy#endif /* REFCLOCK */ 3356280849Scy if (typeorphan != NULL) { 3357280849Scy peers[0].peer = typeorphan; 3358280849Scy nlist = 1; 335954359Sroberto } 336054359Sroberto } 336154359Sroberto 336254359Sroberto /* 3363280849Scy * Mark the candidates at this point as truechimers. 3364132454Sroberto */ 3365280849Scy for (i = 0; i < nlist; i++) { 3366280849Scy peers[i].peer->new_status = CTL_PST_SEL_SELCAND; 3367280849Scy DPRINTF(2, ("select: survivor %s %f\n", 3368280849Scy stoa(&peers[i].peer->srcadr), peers[i].synch)); 3369280849Scy } 3370132454Sroberto 337154359Sroberto /* 3372289764Sglebius * Now, vote outliers off the island by select jitter weighted 3373182007Sroberto * by root distance. Continue voting as long as there are more 3374280849Scy * than sys_minclock survivors and the select jitter of the peer 3375280849Scy * with the worst metric is greater than the minimum peer 3376282408Scy * jitter. Stop if we are about to discard a TRUE or PREFER 3377280849Scy * peer, who of course have the immunity idol. 337854359Sroberto */ 337954359Sroberto while (1) { 338082505Sroberto d = 1e9; 338182505Sroberto e = -1e9; 3382280849Scy g = 0; 338382505Sroberto k = 0; 338482505Sroberto for (i = 0; i < nlist; i++) { 3385280849Scy if (peers[i].error < d) 3386280849Scy d = peers[i].error; 3387280849Scy peers[i].seljit = 0; 338882505Sroberto if (nlist > 1) { 3389280849Scy f = 0; 339082505Sroberto for (j = 0; j < nlist; j++) 3391280849Scy f += DIFF(peers[j].peer->offset, 3392280849Scy peers[i].peer->offset); 3393280849Scy peers[i].seljit = SQRT(f / (nlist - 1)); 339454359Sroberto } 3395280849Scy if (peers[i].seljit * peers[i].synch > e) { 3396280849Scy g = peers[i].seljit; 3397280849Scy e = peers[i].seljit * peers[i].synch; 339854359Sroberto k = i; 339954359Sroberto } 340054359Sroberto } 3401280849Scy g = max(g, LOGTOD(sys_precision)); 3402289764Sglebius if ( nlist <= max(1, sys_minclock) 3403289764Sglebius || g <= d 3404289764Sglebius || ((FLAG_TRUE | FLAG_PREFER) & peers[k].peer->flags)) 3405132454Sroberto break; 3406280849Scy 3407280849Scy DPRINTF(3, ("select: drop %s seljit %.6f jit %.6f\n", 3408280849Scy ntoa(&peers[k].peer->srcadr), g, d)); 3409280849Scy if (nlist > sys_maxclock) 3410280849Scy peers[k].peer->new_status = CTL_PST_SEL_EXCESS; 3411280849Scy for (j = k + 1; j < nlist; j++) 3412280849Scy peers[j - 1] = peers[j]; 341354359Sroberto nlist--; 341454359Sroberto } 341582505Sroberto 341682505Sroberto /* 3417132454Sroberto * What remains is a list usually not greater than sys_minclock 3418280849Scy * peers. Note that unsynchronized peers cannot survive this 3419280849Scy * far. Count and mark these survivors. 3420280849Scy * 3421280849Scy * While at it, count the number of leap warning bits found. 3422280849Scy * This will be used later to vote the system leap warning bit. 3423280849Scy * If a leap warning bit is found on a reference clock, the vote 3424280849Scy * is always won. 3425280849Scy * 3426280849Scy * Choose the system peer using a hybrid metric composed of the 3427280849Scy * selection jitter scaled by the root distance augmented by 3428280849Scy * stratum scaled by sys_mindisp (.001 by default). The goal of 3429280849Scy * the small stratum factor is to avoid clockhop between a 3430280849Scy * reference clock and a network peer which has a refclock and 3431280849Scy * is using an older ntpd, which does not floor sys_rootdisp at 3432280849Scy * sys_mindisp. 3433280849Scy * 3434280849Scy * In contrast, ntpd 4.2.6 and earlier used stratum primarily 3435280849Scy * in selecting the system peer, using a weight of 1 second of 3436280849Scy * additional root distance per stratum. This heavy bias is no 3437280849Scy * longer appropriate, as the scaled root distance provides a 3438280849Scy * more rational metric carrying the cumulative error budget. 343954359Sroberto */ 3440280849Scy e = 1e9; 3441280849Scy speer = 0; 3442280849Scy leap_vote_ins = 0; 3443280849Scy leap_vote_del = 0; 3444182007Sroberto for (i = 0; i < nlist; i++) { 3445280849Scy peer = peers[i].peer; 3446280849Scy peer->unreach = 0; 3447280849Scy peer->new_status = CTL_PST_SEL_SYNCCAND; 3448182007Sroberto sys_survivors++; 3449280849Scy if (peer->leap == LEAP_ADDSECOND) { 3450280849Scy if (peer->flags & FLAG_REFCLOCK) 3451280849Scy leap_vote_ins = nlist; 3452280849Scy else if (leap_vote_ins < nlist) 3453280849Scy leap_vote_ins++; 3454280849Scy } 3455280849Scy if (peer->leap == LEAP_DELSECOND) { 3456280849Scy if (peer->flags & FLAG_REFCLOCK) 3457280849Scy leap_vote_del = nlist; 3458280849Scy else if (leap_vote_del < nlist) 3459280849Scy leap_vote_del++; 3460280849Scy } 3461132454Sroberto if (peer->flags & FLAG_PREFER) 3462132454Sroberto sys_prefer = peer; 3463280849Scy speermet = peers[i].seljit * peers[i].synch + 3464280849Scy peer->stratum * sys_mindisp; 3465280849Scy if (speermet < e) { 3466280849Scy e = speermet; 3467280849Scy speer = i; 3468280849Scy } 346954359Sroberto } 347054359Sroberto 347154359Sroberto /* 3472280849Scy * Unless there are at least sys_misane survivors, leave the 3473280849Scy * building dark. Otherwise, do a clockhop dance. Ordinarily, 3474280849Scy * use the selected survivor speer. However, if the current 3475280849Scy * system peer is not speer, stay with the current system peer 3476280849Scy * as long as it doesn't get too old or too ugly. 3477132454Sroberto */ 3478280849Scy if (nlist > 0 && nlist >= sys_minsane) { 3479280849Scy double x; 3480280849Scy 3481280849Scy typesystem = peers[speer].peer; 3482280849Scy if (osys_peer == NULL || osys_peer == typesystem) { 3483282408Scy sys_clockhop = 0; 3484280849Scy } else if ((x = fabs(typesystem->offset - 3485280849Scy osys_peer->offset)) < sys_mindisp) { 3486280849Scy if (sys_clockhop == 0) 3487280849Scy sys_clockhop = sys_mindisp; 3488280849Scy else 3489280849Scy sys_clockhop *= .5; 3490280849Scy DPRINTF(1, ("select: clockhop %d %.6f %.6f\n", 3491280849Scy j, x, sys_clockhop)); 3492280849Scy if (fabs(x) < sys_clockhop) 3493280849Scy typesystem = osys_peer; 3494280849Scy else 3495280849Scy sys_clockhop = 0; 3496280849Scy } else { 3497280849Scy sys_clockhop = 0; 3498280849Scy } 3499182007Sroberto } 3500132454Sroberto 3501132454Sroberto /* 3502280849Scy * Mitigation rules of the game. We have the pick of the 3503280849Scy * litter in typesystem if any survivors are left. If 3504280849Scy * there is a prefer peer, use its offset and jitter. 3505280849Scy * Otherwise, use the combined offset and jitter of all kitters. 350654359Sroberto */ 3507280849Scy if (typesystem != NULL) { 3508280849Scy if (sys_prefer == NULL) { 3509280849Scy typesystem->new_status = CTL_PST_SEL_SYSPEER; 3510280849Scy clock_combine(peers, sys_survivors, speer); 3511182007Sroberto } else { 3512280849Scy typesystem = sys_prefer; 3513280849Scy sys_clockhop = 0; 3514280849Scy typesystem->new_status = CTL_PST_SEL_SYSPEER; 3515280849Scy sys_offset = typesystem->offset; 3516280849Scy sys_jitter = typesystem->jitter; 3517182007Sroberto } 3518280849Scy DPRINTF(1, ("select: combine offset %.9f jitter %.9f\n", 3519280849Scy sys_offset, sys_jitter)); 3520280849Scy } 3521280849Scy#ifdef REFCLOCK 3522280849Scy /* 3523280849Scy * If a PPS driver is lit and the combined offset is less than 3524280849Scy * 0.4 s, select the driver as the PPS peer and use its offset 3525280849Scy * and jitter. However, if this is the atom driver, use it only 3526280849Scy * if there is a prefer peer or there are no survivors and none 3527280849Scy * are required. 3528280849Scy */ 3529289764Sglebius if ( typepps != NULL 3530289764Sglebius && fabs(sys_offset) < 0.4 3531289764Sglebius && ( typepps->refclktype != REFCLK_ATOM_PPS 3532289764Sglebius || ( typepps->refclktype == REFCLK_ATOM_PPS 3533289764Sglebius && ( sys_prefer != NULL 3534289764Sglebius || (typesystem == NULL && sys_minsane == 0))))) { 3535280849Scy typesystem = typepps; 3536280849Scy sys_clockhop = 0; 3537280849Scy typesystem->new_status = CTL_PST_SEL_PPS; 3538293423Sdelphij sys_offset = typesystem->offset; 3539280849Scy sys_jitter = typesystem->jitter; 3540280849Scy DPRINTF(1, ("select: pps offset %.9f jitter %.9f\n", 3541280849Scy sys_offset, sys_jitter)); 3542280849Scy } 3543280849Scy#endif /* REFCLOCK */ 3544182007Sroberto 3545280849Scy /* 3546280849Scy * If there are no survivors at this point, there is no 3547280849Scy * system peer. If so and this is an old update, keep the 3548280849Scy * current statistics, but do not update the clock. 3549280849Scy */ 3550280849Scy if (typesystem == NULL) { 3551280849Scy if (osys_peer != NULL) { 3552280849Scy if (sys_orphwait > 0) 3553280849Scy orphwait = current_time + sys_orphwait; 3554280849Scy report_event(EVNT_NOPEER, NULL, NULL); 3555182007Sroberto } 3556280849Scy sys_peer = NULL; 3557280849Scy for (peer = peer_list; peer != NULL; peer = peer->p_link) 3558280849Scy peer->status = peer->new_status; 3559280849Scy return; 356054359Sroberto } 3561182007Sroberto 3562182007Sroberto /* 3563280849Scy * Do not use old data, as this may mess up the clock discipline 3564280849Scy * stability. 3565182007Sroberto */ 3566280849Scy if (typesystem->epoch <= sys_epoch) 3567280849Scy return; 3568132454Sroberto 3569280849Scy /* 3570280849Scy * We have found the alpha male. Wind the clock. 3571280849Scy */ 3572280849Scy if (osys_peer != typesystem) 3573280849Scy report_event(PEVNT_NEWPEER, typesystem, NULL); 3574280849Scy for (peer = peer_list; peer != NULL; peer = peer->p_link) 3575280849Scy peer->status = peer->new_status; 3576280849Scy clock_update(typesystem); 357754359Sroberto} 357854359Sroberto 3579182007Sroberto 3580182007Srobertostatic void 358154359Srobertoclock_combine( 3582280849Scy peer_select * peers, /* survivor list */ 3583280849Scy int npeers, /* number of survivors */ 3584280849Scy int syspeer /* index of sys.peer */ 358554359Sroberto ) 358654359Sroberto{ 3587132454Sroberto int i; 3588182007Sroberto double x, y, z, w; 3589132454Sroberto 3590182007Sroberto y = z = w = 0; 359154359Sroberto for (i = 0; i < npeers; i++) { 3592280849Scy x = 1. / peers[i].synch; 3593280849Scy y += x; 3594280849Scy z += x * peers[i].peer->offset; 3595280849Scy w += x * DIFF(peers[i].peer->offset, 3596280849Scy peers[syspeer].peer->offset); 359754359Sroberto } 3598182007Sroberto sys_offset = z / y; 3599280849Scy sys_jitter = SQRT(w / y + SQUARE(peers[syspeer].seljit)); 360054359Sroberto} 360154359Sroberto 3602280849Scy 360354359Sroberto/* 360454359Sroberto * root_distance - compute synchronization distance from peer to root 360554359Sroberto */ 360654359Srobertostatic double 360754359Srobertoroot_distance( 3608280849Scy struct peer *peer /* peer structure pointer */ 360954359Sroberto ) 361054359Sroberto{ 3611280849Scy double dtemp; 3612182007Sroberto 361382505Sroberto /* 3614280849Scy * Root Distance (LAMBDA) is defined as: 3615309007Sdelphij * (delta + DELTA)/2 + epsilon + EPSILON + D 3616280849Scy * 3617280849Scy * where: 3618280849Scy * delta is the round-trip delay 3619280849Scy * DELTA is the root delay 3620309007Sdelphij * epsilon is the peer dispersion 3621280849Scy * + (15 usec each second) 3622280849Scy * EPSILON is the root dispersion 3623309007Sdelphij * D is sys_jitter 3624280849Scy * 3625280849Scy * NB: Think hard about why we are using these values, and what 3626280849Scy * the alternatives are, and the various pros/cons. 3627280849Scy * 3628280849Scy * DLM thinks these are probably the best choices from any of the 3629280849Scy * other worse choices. 3630280849Scy */ 3631280849Scy dtemp = (peer->delay + peer->rootdelay) / 2 3632309007Sdelphij + peer->disp 3633280849Scy + clock_phi * (current_time - peer->update) 3634280849Scy + peer->rootdisp 3635280849Scy + peer->jitter; 3636280849Scy /* 363782505Sroberto * Careful squeak here. The value returned must be greater than 3638182007Sroberto * the minimum root dispersion in order to avoid clockhop with 3639280849Scy * highly precise reference clocks. Note that the root distance 3640280849Scy * cannot exceed the sys_maxdist, as this is the cutoff by the 3641280849Scy * selection algorithm. 364282505Sroberto */ 3643280849Scy if (dtemp < sys_mindisp) 3644280849Scy dtemp = sys_mindisp; 3645280849Scy return (dtemp); 364654359Sroberto} 364754359Sroberto 3648280849Scy 364954359Sroberto/* 365054359Sroberto * peer_xmit - send packet for persistent association. 365154359Sroberto */ 365254359Srobertostatic void 365354359Srobertopeer_xmit( 365454359Sroberto struct peer *peer /* peer structure pointer */ 365554359Sroberto ) 365654359Sroberto{ 365782505Sroberto struct pkt xpkt; /* transmit packet */ 3658280849Scy size_t sendlen, authlen; 3659182007Sroberto keyid_t xkeyid = 0; /* transmit key ID */ 3660280849Scy l_fp xmt_tx, xmt_ty; 366154359Sroberto 3662280849Scy if (!peer->dstadr) /* drop peers without interface */ 3663182007Sroberto return; 3664182007Sroberto 3665280849Scy xpkt.li_vn_mode = PKT_LI_VN_MODE(sys_leap, peer->version, 3666280849Scy peer->hmode); 3667280849Scy xpkt.stratum = STRATUM_TO_PKT(sys_stratum); 366854359Sroberto xpkt.ppoll = peer->hpoll; 366954359Sroberto xpkt.precision = sys_precision; 3670280849Scy xpkt.refid = sys_refid; 3671280849Scy xpkt.rootdelay = HTONS_FP(DTOFP(sys_rootdelay)); 3672280849Scy xpkt.rootdisp = HTONS_FP(DTOUFP(sys_rootdisp)); 367354359Sroberto HTONL_FP(&sys_reftime, &xpkt.reftime); 3674280849Scy HTONL_FP(&peer->rec, &xpkt.org); 3675280849Scy HTONL_FP(&peer->dst, &xpkt.rec); 367654359Sroberto 367754359Sroberto /* 367882505Sroberto * If the received packet contains a MAC, the transmitted packet 367982505Sroberto * is authenticated and contains a MAC. If not, the transmitted 368082505Sroberto * packet is not authenticated. 368182505Sroberto * 3682182007Sroberto * It is most important when autokey is in use that the local 3683182007Sroberto * interface IP address be known before the first packet is 3684182007Sroberto * sent. Otherwise, it is not possible to compute a correct MAC 3685182007Sroberto * the recipient will accept. Thus, the I/O semantics have to do 3686182007Sroberto * a little more work. In particular, the wildcard interface 3687182007Sroberto * might not be usable. 368854359Sroberto */ 368954359Sroberto sendlen = LEN_PKT_NOMAC; 3690293423Sdelphij if ( 3691280849Scy#ifdef AUTOKEY 3692293423Sdelphij !(peer->flags & FLAG_SKEY) && 3693280849Scy#endif /* !AUTOKEY */ 3694293423Sdelphij peer->keyid == 0) { 3695280849Scy 3696280849Scy /* 3697280849Scy * Transmit a-priori timestamps 3698280849Scy */ 3699280849Scy get_systime(&xmt_tx); 3700280849Scy if (peer->flip == 0) { /* basic mode */ 3701280849Scy peer->aorg = xmt_tx; 3702280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 3703280849Scy } else { /* interleaved modes */ 3704280849Scy if (peer->hmode == MODE_BROADCAST) { /* bcst */ 3705280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 3706280849Scy if (peer->flip > 0) 3707280849Scy HTONL_FP(&peer->borg, 3708280849Scy &xpkt.org); 3709280849Scy else 3710280849Scy HTONL_FP(&peer->aorg, 3711280849Scy &xpkt.org); 3712280849Scy } else { /* symmetric */ 3713280849Scy if (peer->flip > 0) 3714280849Scy HTONL_FP(&peer->borg, 3715280849Scy &xpkt.xmt); 3716280849Scy else 3717280849Scy HTONL_FP(&peer->aorg, 3718280849Scy &xpkt.xmt); 3719280849Scy } 3720280849Scy } 3721280849Scy peer->t21_bytes = sendlen; 3722132454Sroberto sendpkt(&peer->srcadr, peer->dstadr, sys_ttl[peer->ttl], 3723280849Scy &xpkt, sendlen); 372482505Sroberto peer->sent++; 3725280849Scy peer->throttle += (1 << peer->minpoll) - 2; 3726280849Scy 3727280849Scy /* 3728280849Scy * Capture a-posteriori timestamps 3729280849Scy */ 3730280849Scy get_systime(&xmt_ty); 3731280849Scy if (peer->flip != 0) { /* interleaved modes */ 3732280849Scy if (peer->flip > 0) 3733280849Scy peer->aorg = xmt_ty; 3734280849Scy else 3735280849Scy peer->borg = xmt_ty; 3736280849Scy peer->flip = -peer->flip; 3737280849Scy } 3738280849Scy L_SUB(&xmt_ty, &xmt_tx); 3739280849Scy LFPTOD(&xmt_ty, peer->xleave); 3740293423Sdelphij DPRINTF(1, ("peer_xmit: at %ld %s->%s mode %d len %zu xmt %#010x.%08x\n", 3741293423Sdelphij current_time, 3742293423Sdelphij peer->dstadr ? stoa(&peer->dstadr->sin) : "-", 3743293423Sdelphij stoa(&peer->srcadr), peer->hmode, sendlen, 3744293423Sdelphij xmt_tx.l_ui, xmt_tx.l_uf)); 374582505Sroberto return; 374682505Sroberto } 374754359Sroberto 374882505Sroberto /* 3749280849Scy * Authentication is enabled, so the transmitted packet must be 3750280849Scy * authenticated. If autokey is enabled, fuss with the various 3751280849Scy * modes; otherwise, symmetric key cryptography is used. 375282505Sroberto */ 3753280849Scy#ifdef AUTOKEY 3754280849Scy if (peer->flags & FLAG_SKEY) { 3755132454Sroberto struct exten *exten; /* extension field */ 375682505Sroberto 375754359Sroberto /* 375882505Sroberto * The Public Key Dance (PKD): Cryptographic credentials 375982505Sroberto * are contained in extension fields, each including a 376082505Sroberto * 4-octet length/code word followed by a 4-octet 376182505Sroberto * association ID and optional additional data. Optional 376282505Sroberto * data includes a 4-octet data length field followed by 376382505Sroberto * the data itself. Request messages are sent from a 376482505Sroberto * configured association; response messages can be sent 376582505Sroberto * from a configured association or can take the fast 376682505Sroberto * path without ever matching an association. Response 376782505Sroberto * messages have the same code as the request, but have 376882505Sroberto * a response bit and possibly an error bit set. In this 376982505Sroberto * implementation, a message may contain no more than 3770280849Scy * one command and one or more responses. 377182505Sroberto * 377282505Sroberto * Cryptographic session keys include both a public and 377382505Sroberto * a private componet. Request and response messages 377482505Sroberto * using extension fields are always sent with the 377582505Sroberto * private component set to zero. Packets without 377682505Sroberto * extension fields indlude the private component when 377782505Sroberto * the session key is generated. 377854359Sroberto */ 377982505Sroberto while (1) { 3780282408Scy 378154359Sroberto /* 378282505Sroberto * Allocate and initialize a keylist if not 378382505Sroberto * already done. Then, use the list in inverse 378482505Sroberto * order, discarding keys once used. Keep the 378582505Sroberto * latest key around until the next one, so 378682505Sroberto * clients can use client/server packets to 378782505Sroberto * compute propagation delay. 378882505Sroberto * 378982505Sroberto * Note that once a key is used from the list, 379082505Sroberto * it is retained in the key cache until the 379182505Sroberto * next key is used. This is to allow a client 379282505Sroberto * to retrieve the encrypted session key 379382505Sroberto * identifier to verify authenticity. 379482505Sroberto * 379582505Sroberto * If for some reason a key is no longer in the 3796280849Scy * key cache, a birthday has happened or the key 3797280849Scy * has expired, so the pseudo-random sequence is 3798280849Scy * broken. In that case, purge the keylist and 3799280849Scy * regenerate it. 380054359Sroberto */ 380182505Sroberto if (peer->keynumber == 0) 380282505Sroberto make_keylist(peer, peer->dstadr); 380382505Sroberto else 380482505Sroberto peer->keynumber--; 380582505Sroberto xkeyid = peer->keylist[peer->keynumber]; 380682505Sroberto if (authistrusted(xkeyid)) 380782505Sroberto break; 380882505Sroberto else 380982505Sroberto key_expire(peer); 381054359Sroberto } 381182505Sroberto peer->keyid = xkeyid; 3812182007Sroberto exten = NULL; 381382505Sroberto switch (peer->hmode) { 381454359Sroberto 3815280849Scy /* 3816280849Scy * In broadcast server mode the autokey values are 3817280849Scy * required by the broadcast clients. Push them when a 3818280849Scy * new keylist is generated; otherwise, push the 3819280849Scy * association message so the client can request them at 3820280849Scy * other times. 3821280849Scy */ 382282505Sroberto case MODE_BROADCAST: 382382505Sroberto if (peer->flags & FLAG_ASSOC) 3824132454Sroberto exten = crypto_args(peer, CRYPTO_AUTO | 3825280849Scy CRYPTO_RESP, peer->associd, NULL); 382682505Sroberto else 3827132454Sroberto exten = crypto_args(peer, CRYPTO_ASSOC | 3828280849Scy CRYPTO_RESP, peer->associd, NULL); 382982505Sroberto break; 383082505Sroberto 383154359Sroberto /* 3832282408Scy * In symmetric modes the parameter, certificate, 3833280849Scy * identity, cookie and autokey exchanges are 3834280849Scy * required. The leapsecond exchange is optional. But, a 3835280849Scy * peer will not believe the other peer until the other 3836280849Scy * peer has synchronized, so the certificate exchange 3837280849Scy * might loop until then. If a peer finds a broken 3838280849Scy * autokey sequence, it uses the autokey exchange to 3839280849Scy * retrieve the autokey values. In any case, if a new 3840280849Scy * keylist is generated, the autokey values are pushed. 384154359Sroberto */ 384282505Sroberto case MODE_ACTIVE: 384382505Sroberto case MODE_PASSIVE: 3844280849Scy 3845182007Sroberto /* 3846280849Scy * Parameter, certificate and identity. 3847182007Sroberto */ 384882505Sroberto if (!peer->crypto) 3849132454Sroberto exten = crypto_args(peer, CRYPTO_ASSOC, 3850280849Scy peer->associd, hostval.ptr); 3851280849Scy else if (!(peer->crypto & CRYPTO_FLAG_CERT)) 3852132454Sroberto exten = crypto_args(peer, CRYPTO_CERT, 3853280849Scy peer->associd, peer->issuer); 3854182007Sroberto else if (!(peer->crypto & CRYPTO_FLAG_VRFY)) 3855182007Sroberto exten = crypto_args(peer, 3856280849Scy crypto_ident(peer), peer->associd, 3857280849Scy NULL); 3858132454Sroberto 3859132454Sroberto /* 3860280849Scy * Cookie and autokey. We request the cookie 3861280849Scy * only when the this peer and the other peer 3862280849Scy * are synchronized. But, this peer needs the 3863280849Scy * autokey values when the cookie is zero. Any 3864280849Scy * time we regenerate the key list, we offer the 3865280849Scy * autokey values without being asked. If for 3866280849Scy * some reason either peer finds a broken 3867280849Scy * autokey sequence, the autokey exchange is 3868280849Scy * used to retrieve the autokey values. 3869132454Sroberto */ 3870289764Sglebius else if ( sys_leap != LEAP_NOTINSYNC 3871289764Sglebius && peer->leap != LEAP_NOTINSYNC 3872289764Sglebius && !(peer->crypto & CRYPTO_FLAG_COOK)) 3873132454Sroberto exten = crypto_args(peer, CRYPTO_COOK, 3874280849Scy peer->associd, NULL); 3875132454Sroberto else if (!(peer->crypto & CRYPTO_FLAG_AUTO)) 3876132454Sroberto exten = crypto_args(peer, CRYPTO_AUTO, 3877280849Scy peer->associd, NULL); 3878289764Sglebius else if ( peer->flags & FLAG_ASSOC 3879289764Sglebius && peer->crypto & CRYPTO_FLAG_SIGN) 3880280849Scy exten = crypto_args(peer, CRYPTO_AUTO | 3881280849Scy CRYPTO_RESP, peer->assoc, NULL); 3882132454Sroberto 3883132454Sroberto /* 3884280849Scy * Wait for clock sync, then sign the 3885280849Scy * certificate and retrieve the leapsecond 3886280849Scy * values. 3887132454Sroberto */ 3888280849Scy else if (sys_leap == LEAP_NOTINSYNC) 3889280849Scy break; 3890280849Scy 3891280849Scy else if (!(peer->crypto & CRYPTO_FLAG_SIGN)) 3892280849Scy exten = crypto_args(peer, CRYPTO_SIGN, 3893280849Scy peer->associd, hostval.ptr); 3894280849Scy else if (!(peer->crypto & CRYPTO_FLAG_LEAP)) 3895280849Scy exten = crypto_args(peer, CRYPTO_LEAP, 3896280849Scy peer->associd, NULL); 389782505Sroberto break; 389882505Sroberto 389982505Sroberto /* 3900280849Scy * In client mode the parameter, certificate, identity, 3901280849Scy * cookie and sign exchanges are required. The 3902280849Scy * leapsecond exchange is optional. If broadcast client 3903280849Scy * mode the same exchanges are required, except that the 3904280849Scy * autokey exchange is substitutes for the cookie 3905280849Scy * exchange, since the cookie is always zero. If the 3906280849Scy * broadcast client finds a broken autokey sequence, it 3907280849Scy * uses the autokey exchange to retrieve the autokey 3908280849Scy * values. 390982505Sroberto */ 391082505Sroberto case MODE_CLIENT: 3911280849Scy 3912182007Sroberto /* 3913280849Scy * Parameter, certificate and identity. 3914182007Sroberto */ 391582505Sroberto if (!peer->crypto) 3916132454Sroberto exten = crypto_args(peer, CRYPTO_ASSOC, 3917280849Scy peer->associd, hostval.ptr); 3918280849Scy else if (!(peer->crypto & CRYPTO_FLAG_CERT)) 3919132454Sroberto exten = crypto_args(peer, CRYPTO_CERT, 3920280849Scy peer->associd, peer->issuer); 3921182007Sroberto else if (!(peer->crypto & CRYPTO_FLAG_VRFY)) 3922182007Sroberto exten = crypto_args(peer, 3923280849Scy crypto_ident(peer), peer->associd, 3924280849Scy NULL); 3925132454Sroberto 3926132454Sroberto /* 3927280849Scy * Cookie and autokey. These are requests, but 3928280849Scy * we use the peer association ID with autokey 3929280849Scy * rather than our own. 3930132454Sroberto */ 3931280849Scy else if (!(peer->crypto & CRYPTO_FLAG_COOK)) 3932132454Sroberto exten = crypto_args(peer, CRYPTO_COOK, 3933280849Scy peer->associd, NULL); 3934280849Scy else if (!(peer->crypto & CRYPTO_FLAG_AUTO)) 3935132454Sroberto exten = crypto_args(peer, CRYPTO_AUTO, 3936280849Scy peer->assoc, NULL); 3937132454Sroberto 3938132454Sroberto /* 3939280849Scy * Wait for clock sync, then sign the 3940280849Scy * certificate and retrieve the leapsecond 3941280849Scy * values. 3942132454Sroberto */ 3943280849Scy else if (sys_leap == LEAP_NOTINSYNC) 3944280849Scy break; 3945280849Scy 3946280849Scy else if (!(peer->crypto & CRYPTO_FLAG_SIGN)) 3947132454Sroberto exten = crypto_args(peer, CRYPTO_SIGN, 3948280849Scy peer->associd, hostval.ptr); 3949280849Scy else if (!(peer->crypto & CRYPTO_FLAG_LEAP)) 3950280849Scy exten = crypto_args(peer, CRYPTO_LEAP, 3951280849Scy peer->associd, NULL); 395282505Sroberto break; 395382505Sroberto } 395482505Sroberto 395582505Sroberto /* 3956280849Scy * Add a queued extension field if present. This is 3957280849Scy * always a request message, so the reply ID is already 3958280849Scy * in the message. If an error occurs, the error bit is 3959280849Scy * lit in the response. 3960182007Sroberto */ 3961182007Sroberto if (peer->cmmd != NULL) { 3962280849Scy u_int32 temp32; 3963280849Scy 3964280849Scy temp32 = CRYPTO_RESP; 3965280849Scy peer->cmmd->opcode |= htonl(temp32); 3966280849Scy sendlen += crypto_xmit(peer, &xpkt, NULL, 3967280849Scy sendlen, peer->cmmd, 0); 3968182007Sroberto free(peer->cmmd); 3969182007Sroberto peer->cmmd = NULL; 3970182007Sroberto } 3971280849Scy 3972280849Scy /* 3973280849Scy * Add an extension field created above. All but the 3974280849Scy * autokey response message are request messages. 3975280849Scy */ 3976182007Sroberto if (exten != NULL) { 3977280849Scy if (exten->opcode != 0) 3978280849Scy sendlen += crypto_xmit(peer, &xpkt, 3979280849Scy NULL, sendlen, exten, 0); 3980182007Sroberto free(exten); 3981182007Sroberto } 3982182007Sroberto 3983182007Sroberto /* 3984280849Scy * Calculate the next session key. Since extension 3985280849Scy * fields are present, the cookie value is zero. 398682505Sroberto */ 3987280849Scy if (sendlen > (int)LEN_PKT_NOMAC) { 398882505Sroberto session_key(&peer->dstadr->sin, &peer->srcadr, 398982505Sroberto xkeyid, 0, 2); 3990182007Sroberto } 3991282408Scy } 3992280849Scy#endif /* AUTOKEY */ 3993182007Sroberto 3994182007Sroberto /* 3995280849Scy * Transmit a-priori timestamps 3996182007Sroberto */ 3997280849Scy get_systime(&xmt_tx); 3998280849Scy if (peer->flip == 0) { /* basic mode */ 3999280849Scy peer->aorg = xmt_tx; 4000280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 4001280849Scy } else { /* interleaved modes */ 4002280849Scy if (peer->hmode == MODE_BROADCAST) { /* bcst */ 4003280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 4004280849Scy if (peer->flip > 0) 4005280849Scy HTONL_FP(&peer->borg, &xpkt.org); 4006280849Scy else 4007280849Scy HTONL_FP(&peer->aorg, &xpkt.org); 4008280849Scy } else { /* symmetric */ 4009280849Scy if (peer->flip > 0) 4010280849Scy HTONL_FP(&peer->borg, &xpkt.xmt); 4011280849Scy else 4012280849Scy HTONL_FP(&peer->aorg, &xpkt.xmt); 4013280849Scy } 4014280849Scy } 401582505Sroberto xkeyid = peer->keyid; 401682505Sroberto authlen = authencrypt(xkeyid, (u_int32 *)&xpkt, sendlen); 401782505Sroberto if (authlen == 0) { 4018280849Scy report_event(PEVNT_AUTH, peer, "no key"); 4019280849Scy peer->flash |= TEST5; /* auth error */ 4020280849Scy peer->badauth++; 402182505Sroberto return; 402282505Sroberto } 402382505Sroberto sendlen += authlen; 4024280849Scy#ifdef AUTOKEY 402582505Sroberto if (xkeyid > NTP_MAXKEY) 402682505Sroberto authtrust(xkeyid, 0); 4027280849Scy#endif /* AUTOKEY */ 402882505Sroberto if (sendlen > sizeof(xpkt)) { 4029293423Sdelphij msyslog(LOG_ERR, "peer_xmit: buffer overflow %zu", sendlen); 4030132454Sroberto exit (-1); 403182505Sroberto } 4032280849Scy peer->t21_bytes = sendlen; 4033132454Sroberto sendpkt(&peer->srcadr, peer->dstadr, sys_ttl[peer->ttl], &xpkt, 4034280849Scy sendlen); 4035280849Scy peer->sent++; 4036280849Scy peer->throttle += (1 << peer->minpoll) - 2; 403782505Sroberto 403882505Sroberto /* 4039280849Scy * Capture a-posteriori timestamps 404082505Sroberto */ 4041280849Scy get_systime(&xmt_ty); 4042280849Scy if (peer->flip != 0) { /* interleaved modes */ 4043280849Scy if (peer->flip > 0) 4044280849Scy peer->aorg = xmt_ty; 4045280849Scy else 4046280849Scy peer->borg = xmt_ty; 4047280849Scy peer->flip = -peer->flip; 4048280849Scy } 4049280849Scy L_SUB(&xmt_ty, &xmt_tx); 4050280849Scy LFPTOD(&xmt_ty, peer->xleave); 4051280849Scy#ifdef AUTOKEY 4052293423Sdelphij DPRINTF(1, ("peer_xmit: at %ld %s->%s mode %d keyid %08x len %zu index %d\n", 4053280849Scy current_time, latoa(peer->dstadr), 4054280849Scy ntoa(&peer->srcadr), peer->hmode, xkeyid, sendlen, 4055293423Sdelphij peer->keynumber)); 4056280849Scy#else /* !AUTOKEY follows */ 4057293423Sdelphij DPRINTF(1, ("peer_xmit: at %ld %s->%s mode %d keyid %08x len %d\n", 4058280849Scy current_time, peer->dstadr ? 4059280849Scy ntoa(&peer->dstadr->sin) : "-", 4060293423Sdelphij ntoa(&peer->srcadr), peer->hmode, xkeyid, sendlen)); 4061280849Scy#endif /* !AUTOKEY */ 4062293423Sdelphij 4063293423Sdelphij return; 406454359Sroberto} 406554359Sroberto 406682505Sroberto 4067285169Scy#ifdef LEAP_SMEAR 4068285169Scy 4069285169Scystatic void 4070293423Sdelphijleap_smear_add_offs( 4071293423Sdelphij l_fp *t, 4072293423Sdelphij l_fp *t_recv 4073293423Sdelphij ) 4074293423Sdelphij{ 4075293423Sdelphij 4076285169Scy L_ADD(t, &leap_smear.offset); 4077293423Sdelphij 4078309007Sdelphij /* 4079309007Sdelphij ** XXX: Should the smear be added to the root dispersion? 4080309007Sdelphij */ 4081309007Sdelphij 4082293423Sdelphij return; 4083285169Scy} 4084285169Scy 4085285169Scy#endif /* LEAP_SMEAR */ 4086285169Scy 4087285169Scy 408854359Sroberto/* 408982505Sroberto * fast_xmit - Send packet for nonpersistent association. Note that 409082505Sroberto * neither the source or destination can be a broadcast address. 409154359Sroberto */ 409254359Srobertostatic void 409354359Srobertofast_xmit( 409454359Sroberto struct recvbuf *rbufp, /* receive packet pointer */ 4095280849Scy int xmode, /* receive mode */ 4096132454Sroberto keyid_t xkeyid, /* transmit key ID */ 4097280849Scy int flags /* restrict mask */ 409854359Sroberto ) 409954359Sroberto{ 4100280849Scy struct pkt xpkt; /* transmit packet structure */ 4101280849Scy struct pkt *rpkt; /* receive packet structure */ 4102280849Scy l_fp xmt_tx, xmt_ty; 4103293423Sdelphij size_t sendlen; 4104280849Scy#ifdef AUTOKEY 4105132454Sroberto u_int32 temp32; 4106132454Sroberto#endif 410754359Sroberto 410854359Sroberto /* 410982505Sroberto * Initialize transmit packet header fields from the receive 4110280849Scy * buffer provided. We leave the fields intact as received, but 4111280849Scy * set the peer poll at the maximum of the receive peer poll and 4112280849Scy * the system minimum poll (ntp_minpoll). This is for KoD rate 4113280849Scy * control and not strictly specification compliant, but doesn't 4114280849Scy * break anything. 4115182007Sroberto * 4116280849Scy * If the gazinta was from a multicast address, the gazoutta 4117280849Scy * must go out another way. 411854359Sroberto */ 411954359Sroberto rpkt = &rbufp->recv_pkt; 4120182007Sroberto if (rbufp->dstadr->flags & INT_MCASTOPEN) 412182505Sroberto rbufp->dstadr = findinterface(&rbufp->recv_srcadr); 412282505Sroberto 412382505Sroberto /* 4124280849Scy * If this is a kiss-o'-death (KoD) packet, show leap 4125182007Sroberto * unsynchronized, stratum zero, reference ID the four-character 4126280849Scy * kiss code and system root delay. Note we don't reveal the 4127280849Scy * local time, so these packets can't be used for 4128280849Scy * synchronization. 4129182007Sroberto */ 4130280849Scy if (flags & RES_KOD) { 4131280849Scy sys_kodsent++; 4132132454Sroberto xpkt.li_vn_mode = PKT_LI_VN_MODE(LEAP_NOTINSYNC, 4133132454Sroberto PKT_VERSION(rpkt->li_vn_mode), xmode); 4134280849Scy xpkt.stratum = STRATUM_PKT_UNSPEC; 4135280849Scy xpkt.ppoll = max(rpkt->ppoll, ntp_minpoll); 4136280849Scy xpkt.precision = rpkt->precision; 4137182007Sroberto memcpy(&xpkt.refid, "RATE", 4); 4138280849Scy xpkt.rootdelay = rpkt->rootdelay; 4139280849Scy xpkt.rootdisp = rpkt->rootdisp; 4140280849Scy xpkt.reftime = rpkt->reftime; 4141280849Scy xpkt.org = rpkt->xmt; 4142280849Scy xpkt.rec = rpkt->xmt; 4143280849Scy xpkt.xmt = rpkt->xmt; 4144182007Sroberto 4145182007Sroberto /* 4146182007Sroberto * This is a normal packet. Use the system variables. 4147182007Sroberto */ 4148280849Scy } else { 4149285169Scy#ifdef LEAP_SMEAR 4150285169Scy /* 4151285169Scy * Make copies of the variables which can be affected by smearing. 4152285169Scy */ 4153285169Scy l_fp this_ref_time; 4154285169Scy l_fp this_recv_time; 4155285169Scy#endif 4156285169Scy 4157285169Scy /* 4158285169Scy * If we are inside the leap smear interval we add the current smear offset to 4159285169Scy * the packet receive time, to the packet transmit time, and eventually to the 4160285169Scy * reftime to make sure the reftime isn't later than the transmit/receive times. 4161285169Scy */ 4162285169Scy xpkt.li_vn_mode = PKT_LI_VN_MODE(xmt_leap, 416382505Sroberto PKT_VERSION(rpkt->li_vn_mode), xmode); 4164285169Scy 416582505Sroberto xpkt.stratum = STRATUM_TO_PKT(sys_stratum); 4166280849Scy xpkt.ppoll = max(rpkt->ppoll, ntp_minpoll); 4167280849Scy xpkt.precision = sys_precision; 416882505Sroberto xpkt.refid = sys_refid; 4169182007Sroberto xpkt.rootdelay = HTONS_FP(DTOFP(sys_rootdelay)); 4170280849Scy xpkt.rootdisp = HTONS_FP(DTOUFP(sys_rootdisp)); 4171285169Scy 4172285169Scy#ifdef LEAP_SMEAR 4173285169Scy this_ref_time = sys_reftime; 4174285169Scy if (leap_smear.in_progress) { 4175285169Scy leap_smear_add_offs(&this_ref_time, NULL); 4176285169Scy xpkt.refid = convertLFPToRefID(leap_smear.offset); 4177285169Scy DPRINTF(2, ("fast_xmit: leap_smear.in_progress: refid %8x, smear %s\n", 4178285169Scy ntohl(xpkt.refid), 4179285169Scy lfptoa(&leap_smear.offset, 8) 4180285169Scy )); 4181285169Scy } 4182285169Scy HTONL_FP(&this_ref_time, &xpkt.reftime); 4183285169Scy#else 4184280849Scy HTONL_FP(&sys_reftime, &xpkt.reftime); 4185285169Scy#endif 4186285169Scy 4187280849Scy xpkt.org = rpkt->xmt; 4188285169Scy 4189285169Scy#ifdef LEAP_SMEAR 4190285169Scy this_recv_time = rbufp->recv_time; 4191285169Scy if (leap_smear.in_progress) 4192285169Scy leap_smear_add_offs(&this_recv_time, NULL); 4193285169Scy HTONL_FP(&this_recv_time, &xpkt.rec); 4194285169Scy#else 4195280849Scy HTONL_FP(&rbufp->recv_time, &xpkt.rec); 4196285169Scy#endif 4197285169Scy 4198280849Scy get_systime(&xmt_tx); 4199285169Scy#ifdef LEAP_SMEAR 4200285169Scy if (leap_smear.in_progress) 4201285169Scy leap_smear_add_offs(&xmt_tx, &this_recv_time); 4202285169Scy#endif 4203280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 4204280849Scy } 4205182007Sroberto 4206280849Scy#ifdef HAVE_NTP_SIGND 4207280849Scy if (flags & RES_MSSNTP) { 4208280849Scy send_via_ntp_signd(rbufp, xmode, xkeyid, flags, &xpkt); 4209280849Scy return; 421082505Sroberto } 4211280849Scy#endif /* HAVE_NTP_SIGND */ 421282505Sroberto 421382505Sroberto /* 421482505Sroberto * If the received packet contains a MAC, the transmitted packet 421582505Sroberto * is authenticated and contains a MAC. If not, the transmitted 421682505Sroberto * packet is not authenticated. 421782505Sroberto */ 421854359Sroberto sendlen = LEN_PKT_NOMAC; 421982505Sroberto if (rbufp->recv_length == sendlen) { 422082505Sroberto sendpkt(&rbufp->recv_srcadr, rbufp->dstadr, 0, &xpkt, 422156749Sroberto sendlen); 4222293423Sdelphij DPRINTF(1, ("fast_xmit: at %ld %s->%s mode %d len %lu\n", 4223132454Sroberto current_time, stoa(&rbufp->dstadr->sin), 4224293423Sdelphij stoa(&rbufp->recv_srcadr), xmode, 4225293423Sdelphij (u_long)sendlen)); 422682505Sroberto return; 422782505Sroberto } 422854359Sroberto 422982505Sroberto /* 423082505Sroberto * The received packet contains a MAC, so the transmitted packet 4231182007Sroberto * must be authenticated. For symmetric key cryptography, use 4232182007Sroberto * the predefined and trusted symmetric keys to generate the 4233182007Sroberto * cryptosum. For autokey cryptography, use the server private 4234182007Sroberto * value to generate the cookie, which is unique for every 4235182007Sroberto * source-destination-key ID combination. 423682505Sroberto */ 4237280849Scy#ifdef AUTOKEY 423882505Sroberto if (xkeyid > NTP_MAXKEY) { 423982505Sroberto keyid_t cookie; 424082505Sroberto 424154359Sroberto /* 424282505Sroberto * The only way to get here is a reply to a legitimate 424382505Sroberto * client request message, so the mode must be 424482505Sroberto * MODE_SERVER. If an extension field is present, there 424582505Sroberto * can be only one and that must be a command. Do what 424682505Sroberto * needs, but with private value of zero so the poor 424782505Sroberto * jerk can decode it. If no extension field is present, 424882505Sroberto * use the cookie to generate the session key. 424954359Sroberto */ 425082505Sroberto cookie = session_key(&rbufp->recv_srcadr, 425182505Sroberto &rbufp->dstadr->sin, 0, sys_private, 0); 4252293423Sdelphij if ((size_t)rbufp->recv_length > sendlen + MAX_MAC_LEN) { 425382505Sroberto session_key(&rbufp->dstadr->sin, 425482505Sroberto &rbufp->recv_srcadr, xkeyid, 0, 2); 4255132454Sroberto temp32 = CRYPTO_RESP; 4256132454Sroberto rpkt->exten[0] |= htonl(temp32); 4257280849Scy sendlen += crypto_xmit(NULL, &xpkt, rbufp, 4258280849Scy sendlen, (struct exten *)rpkt->exten, 4259280849Scy cookie); 426082505Sroberto } else { 426182505Sroberto session_key(&rbufp->dstadr->sin, 426282505Sroberto &rbufp->recv_srcadr, xkeyid, cookie, 2); 426382505Sroberto } 426482505Sroberto } 4265280849Scy#endif /* AUTOKEY */ 4266280849Scy get_systime(&xmt_tx); 4267280849Scy sendlen += authencrypt(xkeyid, (u_int32 *)&xpkt, sendlen); 4268280849Scy#ifdef AUTOKEY 426982505Sroberto if (xkeyid > NTP_MAXKEY) 427082505Sroberto authtrust(xkeyid, 0); 4271280849Scy#endif /* AUTOKEY */ 427282505Sroberto sendpkt(&rbufp->recv_srcadr, rbufp->dstadr, 0, &xpkt, sendlen); 4273280849Scy get_systime(&xmt_ty); 4274280849Scy L_SUB(&xmt_ty, &xmt_tx); 4275280849Scy sys_authdelay = xmt_ty; 4276293423Sdelphij DPRINTF(1, ("fast_xmit: at %ld %s->%s mode %d keyid %08x len %lu\n", 427782505Sroberto current_time, ntoa(&rbufp->dstadr->sin), 4278293423Sdelphij ntoa(&rbufp->recv_srcadr), xmode, xkeyid, 4279293423Sdelphij (u_long)sendlen)); 428054359Sroberto} 428154359Sroberto 428282505Sroberto 428354359Sroberto/* 4284280849Scy * pool_xmit - resolve hostname or send unicast solicitation for pool. 4285280849Scy */ 4286280849Scystatic void 4287280849Scypool_xmit( 4288280849Scy struct peer *pool /* pool solicitor association */ 4289280849Scy ) 4290280849Scy{ 4291280849Scy#ifdef WORKER 4292280849Scy struct pkt xpkt; /* transmit packet structure */ 4293280849Scy struct addrinfo hints; 4294280849Scy int rc; 4295280849Scy struct interface * lcladr; 4296280849Scy sockaddr_u * rmtadr; 4297280849Scy int restrict_mask; 4298280849Scy struct peer * p; 4299280849Scy l_fp xmt_tx; 4300280849Scy 4301280849Scy if (NULL == pool->ai) { 4302280849Scy if (pool->addrs != NULL) { 4303280849Scy /* free() is used with copy_addrinfo_list() */ 4304280849Scy free(pool->addrs); 4305280849Scy pool->addrs = NULL; 4306280849Scy } 4307280849Scy ZERO(hints); 4308280849Scy hints.ai_family = AF(&pool->srcadr); 4309280849Scy hints.ai_socktype = SOCK_DGRAM; 4310280849Scy hints.ai_protocol = IPPROTO_UDP; 4311280849Scy /* ignore getaddrinfo_sometime() errors, we will retry */ 4312280849Scy rc = getaddrinfo_sometime( 4313280849Scy pool->hostname, 4314280849Scy "ntp", 4315280849Scy &hints, 4316280849Scy 0, /* no retry */ 4317280849Scy &pool_name_resolved, 4318280849Scy (void *)(intptr_t)pool->associd); 4319280849Scy if (!rc) 4320280849Scy DPRINTF(1, ("pool DNS lookup %s started\n", 4321280849Scy pool->hostname)); 4322280849Scy else 4323280849Scy msyslog(LOG_ERR, 4324289764Sglebius "unable to start pool DNS %s: %m", 4325280849Scy pool->hostname); 4326280849Scy return; 4327280849Scy } 4328280849Scy 4329280849Scy do { 4330280849Scy /* copy_addrinfo_list ai_addr points to a sockaddr_u */ 4331280849Scy rmtadr = (sockaddr_u *)(void *)pool->ai->ai_addr; 4332280849Scy pool->ai = pool->ai->ai_next; 4333280849Scy p = findexistingpeer(rmtadr, NULL, NULL, MODE_CLIENT, 0); 4334280849Scy } while (p != NULL && pool->ai != NULL); 4335280849Scy if (p != NULL) 4336280849Scy return; /* out of addresses, re-query DNS next poll */ 4337280849Scy restrict_mask = restrictions(rmtadr); 4338280849Scy if (RES_FLAGS & restrict_mask) 4339282408Scy restrict_source(rmtadr, 0, 4340280849Scy current_time + POOL_SOLICIT_WINDOW + 1); 4341280849Scy lcladr = findinterface(rmtadr); 4342280849Scy memset(&xpkt, 0, sizeof(xpkt)); 4343280849Scy xpkt.li_vn_mode = PKT_LI_VN_MODE(sys_leap, pool->version, 4344280849Scy MODE_CLIENT); 4345280849Scy xpkt.stratum = STRATUM_TO_PKT(sys_stratum); 4346280849Scy xpkt.ppoll = pool->hpoll; 4347280849Scy xpkt.precision = sys_precision; 4348280849Scy xpkt.refid = sys_refid; 4349280849Scy xpkt.rootdelay = HTONS_FP(DTOFP(sys_rootdelay)); 4350280849Scy xpkt.rootdisp = HTONS_FP(DTOUFP(sys_rootdisp)); 4351280849Scy HTONL_FP(&sys_reftime, &xpkt.reftime); 4352280849Scy get_systime(&xmt_tx); 4353280849Scy pool->aorg = xmt_tx; 4354280849Scy HTONL_FP(&xmt_tx, &xpkt.xmt); 4355280849Scy sendpkt(rmtadr, lcladr, sys_ttl[pool->ttl], &xpkt, 4356280849Scy LEN_PKT_NOMAC); 4357280849Scy pool->sent++; 4358280849Scy pool->throttle += (1 << pool->minpoll) - 2; 4359293423Sdelphij DPRINTF(1, ("pool_xmit: at %ld %s->%s pool\n", 4360293423Sdelphij current_time, latoa(lcladr), stoa(rmtadr))); 4361280849Scy msyslog(LOG_INFO, "Soliciting pool server %s", stoa(rmtadr)); 4362280849Scy#endif /* WORKER */ 4363280849Scy} 4364280849Scy 4365280849Scy 4366280849Scy#ifdef AUTOKEY 4367280849Scy /* 4368280849Scy * group_test - test if this is the same group 4369280849Scy * 4370280849Scy * host assoc return action 4371280849Scy * none none 0 mobilize * 4372280849Scy * none group 0 mobilize * 4373280849Scy * group none 0 mobilize * 4374280849Scy * group group 1 mobilize 4375280849Scy * group different 1 ignore 4376280849Scy * * ignore if notrust 4377280849Scy */ 4378293423Sdelphijint 4379293423Sdelphijgroup_test( 4380280849Scy char *grp, 4381280849Scy char *ident 4382280849Scy ) 4383280849Scy{ 4384280849Scy if (grp == NULL) 4385280849Scy return (0); 4386280849Scy 4387280849Scy if (strcmp(grp, sys_groupname) == 0) 4388280849Scy return (0); 4389280849Scy 4390280849Scy if (ident == NULL) 4391280849Scy return (1); 4392280849Scy 4393280849Scy if (strcmp(grp, ident) == 0) 4394280849Scy return (0); 4395280849Scy 4396280849Scy return (1); 4397280849Scy} 4398280849Scy#endif /* AUTOKEY */ 4399280849Scy 4400298695Sdelphij 4401280849Scy#ifdef WORKER 4402280849Scyvoid 4403280849Scypool_name_resolved( 4404280849Scy int rescode, 4405280849Scy int gai_errno, 4406280849Scy void * context, 4407280849Scy const char * name, 4408280849Scy const char * service, 4409280849Scy const struct addrinfo * hints, 4410280849Scy const struct addrinfo * res 4411280849Scy ) 4412280849Scy{ 4413280849Scy struct peer * pool; /* pool solicitor association */ 4414280849Scy associd_t assoc; 4415280849Scy 4416280849Scy if (rescode) { 4417280849Scy msyslog(LOG_ERR, 4418280849Scy "error resolving pool %s: %s (%d)", 4419280849Scy name, gai_strerror(rescode), rescode); 4420280849Scy return; 4421280849Scy } 4422280849Scy 4423280849Scy assoc = (associd_t)(intptr_t)context; 4424280849Scy pool = findpeerbyassoc(assoc); 4425280849Scy if (NULL == pool) { 4426280849Scy msyslog(LOG_ERR, 4427280849Scy "Could not find assoc %u for pool DNS %s", 4428280849Scy assoc, name); 4429280849Scy return; 4430280849Scy } 4431280849Scy DPRINTF(1, ("pool DNS %s completed\n", name)); 4432280849Scy pool->addrs = copy_addrinfo_list(res); 4433280849Scy pool->ai = pool->addrs; 4434280849Scy pool_xmit(pool); 4435280849Scy 4436280849Scy} 4437280849Scy#endif /* WORKER */ 4438280849Scy 4439280849Scy 4440280849Scy#ifdef AUTOKEY 4441280849Scy/* 444282505Sroberto * key_expire - purge the key list 444354359Sroberto */ 444482505Srobertovoid 444582505Srobertokey_expire( 444682505Sroberto struct peer *peer /* peer structure pointer */ 444754359Sroberto ) 444854359Sroberto{ 444954359Sroberto int i; 445054359Sroberto 4451132454Sroberto if (peer->keylist != NULL) { 445282505Sroberto for (i = 0; i <= peer->keynumber; i++) 445382505Sroberto authtrust(peer->keylist[i], 0); 445482505Sroberto free(peer->keylist); 445582505Sroberto peer->keylist = NULL; 445654359Sroberto } 4457132454Sroberto value_free(&peer->sndval); 4458132454Sroberto peer->keynumber = 0; 4459280849Scy peer->flags &= ~FLAG_ASSOC; 4460293423Sdelphij DPRINTF(1, ("key_expire: at %lu associd %d\n", current_time, 4461293423Sdelphij peer->associd)); 446254359Sroberto} 4463280849Scy#endif /* AUTOKEY */ 446454359Sroberto 4465132454Sroberto 446654359Sroberto/* 4467280849Scy * local_refid(peer) - check peer refid to avoid selecting peers 4468280849Scy * currently synced to this ntpd. 4469280849Scy */ 4470280849Scystatic int 4471280849Scylocal_refid( 4472280849Scy struct peer * p 4473280849Scy ) 4474280849Scy{ 4475280849Scy endpt * unicast_ep; 4476280849Scy 4477280849Scy if (p->dstadr != NULL && !(INT_MCASTIF & p->dstadr->flags)) 4478280849Scy unicast_ep = p->dstadr; 4479280849Scy else 4480280849Scy unicast_ep = findinterface(&p->srcadr); 4481280849Scy 4482280849Scy if (unicast_ep != NULL && p->refid == unicast_ep->addr_refid) 4483280849Scy return TRUE; 4484280849Scy else 4485280849Scy return FALSE; 4486280849Scy} 4487280849Scy 4488280849Scy 4489280849Scy/* 4490132454Sroberto * Determine if the peer is unfit for synchronization 4491132454Sroberto * 4492132454Sroberto * A peer is unfit for synchronization if 4493182007Sroberto * > TEST10 bad leap or stratum below floor or at or above ceiling 4494280849Scy * > TEST11 root distance exceeded for remote peer 4495182007Sroberto * > TEST12 a direct or indirect synchronization loop would form 4496182007Sroberto * > TEST13 unreachable or noselect 4497132454Sroberto */ 4498182007Srobertoint /* FALSE if fit, TRUE if unfit */ 4499132454Srobertopeer_unfit( 4500132454Sroberto struct peer *peer /* peer structure pointer */ 4501132454Sroberto ) 4502132454Sroberto{ 4503182007Sroberto int rval = 0; 4504182007Sroberto 4505182007Sroberto /* 4506182007Sroberto * A stratum error occurs if (1) the server has never been 4507182007Sroberto * synchronized, (2) the server stratum is below the floor or 4508280849Scy * greater than or equal to the ceiling. 4509182007Sroberto */ 4510289764Sglebius if ( peer->leap == LEAP_NOTINSYNC 4511289764Sglebius || peer->stratum < sys_floor 4512309007Sdelphij || peer->stratum >= sys_ceiling) { 4513280849Scy rval |= TEST10; /* bad synch or stratum */ 4514309007Sdelphij } 4515182007Sroberto 4516182007Sroberto /* 4517280849Scy * A distance error for a remote peer occurs if the root 4518280849Scy * distance is greater than or equal to the distance threshold 4519280849Scy * plus the increment due to one host poll interval. 4520182007Sroberto */ 4521289764Sglebius if ( !(peer->flags & FLAG_REFCLOCK) 4522289764Sglebius && root_distance(peer) >= sys_maxdist 4523309007Sdelphij + clock_phi * ULOGTOD(peer->hpoll)) { 4524182007Sroberto rval |= TEST11; /* distance exceeded */ 4525309007Sdelphij } 4526182007Sroberto 4527182007Sroberto /* 4528182007Sroberto * A loop error occurs if the remote peer is synchronized to the 4529280849Scy * local peer or if the remote peer is synchronized to the same 4530280849Scy * server as the local peer but only if the remote peer is 4531280849Scy * neither a reference clock nor an orphan. 4532182007Sroberto */ 4533309007Sdelphij if (peer->stratum > 1 && local_refid(peer)) { 4534280849Scy rval |= TEST12; /* synchronization loop */ 4535309007Sdelphij } 4536182007Sroberto 4537182007Sroberto /* 4538182007Sroberto * An unreachable error occurs if the server is unreachable or 4539182007Sroberto * the noselect bit is set. 4540182007Sroberto */ 4541309007Sdelphij if (!peer->reach || (peer->flags & FLAG_NOSELECT)) { 4542182007Sroberto rval |= TEST13; /* unreachable */ 4543309007Sdelphij } 4544182007Sroberto 4545182007Sroberto peer->flash &= ~PEER_TEST_MASK; 4546182007Sroberto peer->flash |= rval; 4547182007Sroberto return (rval); 4548132454Sroberto} 4549132454Sroberto 4550132454Sroberto 4551132454Sroberto/* 455254359Sroberto * Find the precision of this particular machine 455354359Sroberto */ 4554280849Scy#define MINSTEP 20e-9 /* minimum clock increment (s) */ 4555280849Scy#define MAXSTEP 1 /* maximum clock increment (s) */ 4556280849Scy#define MINCHANGES 12 /* minimum number of step samples */ 4557280849Scy#define MAXLOOPS ((int)(1. / MINSTEP)) /* avoid infinite loop */ 455854359Sroberto 455954359Sroberto/* 4560280849Scy * This routine measures the system precision defined as the minimum of 4561280849Scy * a sequence of differences between successive readings of the system 4562280849Scy * clock. However, if a difference is less than MINSTEP, the clock has 4563280849Scy * been read more than once during a clock tick and the difference is 4564280849Scy * ignored. We set MINSTEP greater than zero in case something happens 4565280849Scy * like a cache miss, and to tolerate underlying system clocks which 4566280849Scy * ensure each reading is strictly greater than prior readings while 4567280849Scy * using an underlying stepping (not interpolated) clock. 4568132454Sroberto * 4569280849Scy * sys_tick and sys_precision represent the time to read the clock for 4570280849Scy * systems with high-precision clocks, and the tick interval or step 4571280849Scy * size for lower-precision stepping clocks. 4572280849Scy * 4573280849Scy * This routine also measures the time to read the clock on stepping 4574280849Scy * system clocks by counting the number of readings between changes of 4575280849Scy * the underlying clock. With either type of clock, the minimum time 4576280849Scy * to read the clock is saved as sys_fuzz, and used to ensure the 4577280849Scy * get_systime() readings always increase and are fuzzed below sys_fuzz. 457854359Sroberto */ 4579280849Scyvoid 4580280849Scymeasure_precision(void) 458154359Sroberto{ 4582280849Scy /* 4583280849Scy * With sys_fuzz set to zero, get_systime() fuzzing of low bits 4584280849Scy * is effectively disabled. trunc_os_clock is FALSE to disable 4585280849Scy * get_ostime() simulation of a low-precision system clock. 4586280849Scy */ 4587280849Scy set_sys_fuzz(0.); 4588280849Scy trunc_os_clock = FALSE; 4589280849Scy measured_tick = measure_tick_fuzz(); 4590280849Scy set_sys_tick_precision(measured_tick); 4591280849Scy msyslog(LOG_INFO, "proto: precision = %.3f usec (%d)", 4592280849Scy sys_tick * 1e6, sys_precision); 4593280849Scy if (sys_fuzz < sys_tick) { 4594280849Scy msyslog(LOG_NOTICE, "proto: fuzz beneath %.3f usec", 4595280849Scy sys_fuzz * 1e6); 4596280849Scy } 4597280849Scy} 4598280849Scy 4599280849Scy 4600280849Scy/* 4601280849Scy * measure_tick_fuzz() 4602280849Scy * 4603280849Scy * measures the minimum time to read the clock (stored in sys_fuzz) 4604280849Scy * and returns the tick, the larger of the minimum increment observed 4605280849Scy * between successive clock readings and the time to read the clock. 4606280849Scy */ 4607280849Scydouble 4608280849Scymeasure_tick_fuzz(void) 4609280849Scy{ 4610280849Scy l_fp minstep; /* MINSTEP as l_fp */ 4611132454Sroberto l_fp val; /* current seconds fraction */ 4612132454Sroberto l_fp last; /* last seconds fraction */ 4613280849Scy l_fp ldiff; /* val - last */ 4614132454Sroberto double tick; /* computed tick value */ 4615280849Scy double diff; 4616280849Scy long repeats; 4617280849Scy long max_repeats; 4618280849Scy int changes; 4619132454Sroberto int i; /* log2 precision */ 462054359Sroberto 4621280849Scy tick = MAXSTEP; 4622280849Scy max_repeats = 0; 4623280849Scy repeats = 0; 4624280849Scy changes = 0; 4625280849Scy DTOLFP(MINSTEP, &minstep); 4626132454Sroberto get_systime(&last); 4627280849Scy for (i = 0; i < MAXLOOPS && changes < MINCHANGES; i++) { 4628132454Sroberto get_systime(&val); 4629280849Scy ldiff = val; 4630280849Scy L_SUB(&ldiff, &last); 4631132454Sroberto last = val; 4632280849Scy if (L_ISGT(&ldiff, &minstep)) { 4633280849Scy max_repeats = max(repeats, max_repeats); 4634280849Scy repeats = 0; 4635280849Scy changes++; 4636280849Scy LFPTOD(&ldiff, diff); 4637280849Scy tick = min(diff, tick); 4638280849Scy } else { 4639280849Scy repeats++; 4640280849Scy } 464154359Sroberto } 4642280849Scy if (changes < MINCHANGES) { 4643280849Scy msyslog(LOG_ERR, "Fatal error: precision could not be measured (MINSTEP too large?)"); 4644280849Scy exit(1); 4645280849Scy } 4646132454Sroberto 4647280849Scy if (0 == max_repeats) { 4648280849Scy set_sys_fuzz(tick); 4649280849Scy } else { 4650280849Scy set_sys_fuzz(tick / max_repeats); 4651280849Scy } 4652280849Scy 4653280849Scy return tick; 4654280849Scy} 4655280849Scy 4656280849Scy 4657280849Scyvoid 4658280849Scyset_sys_tick_precision( 4659280849Scy double tick 4660280849Scy ) 4661280849Scy{ 4662280849Scy int i; 4663280849Scy 4664280849Scy if (tick > 1.) { 4665280849Scy msyslog(LOG_ERR, 4666280849Scy "unsupported tick %.3f > 1s ignored", tick); 4667280849Scy return; 4668280849Scy } 4669280849Scy if (tick < measured_tick) { 4670280849Scy msyslog(LOG_ERR, 4671280849Scy "proto: tick %.3f less than measured tick %.3f, ignored", 4672280849Scy tick, measured_tick); 4673280849Scy return; 4674280849Scy } else if (tick > measured_tick) { 4675280849Scy trunc_os_clock = TRUE; 4676280849Scy msyslog(LOG_NOTICE, 4677280849Scy "proto: truncating system clock to multiples of %.9f", 4678280849Scy tick); 4679280849Scy } 4680280849Scy sys_tick = tick; 4681280849Scy 4682132454Sroberto /* 4683132454Sroberto * Find the nearest power of two. 4684132454Sroberto */ 4685280849Scy for (i = 0; tick <= 1; i--) 4686132454Sroberto tick *= 2; 4687280849Scy if (tick - 1 > 1 - tick / 2) 4688280849Scy i++; 468954359Sroberto 4690280849Scy sys_precision = (s_char)i; 4691132454Sroberto} 4692132454Sroberto 4693132454Sroberto 4694132454Sroberto/* 469554359Sroberto * init_proto - initialize the protocol module's data 469654359Sroberto */ 469754359Srobertovoid 469854359Srobertoinit_proto(void) 469954359Sroberto{ 4700132454Sroberto l_fp dummy; 4701132454Sroberto int i; 470254359Sroberto 470354359Sroberto /* 470454359Sroberto * Fill in the sys_* stuff. Default is don't listen to 4705280849Scy * broadcasting, require authentication. 470654359Sroberto */ 4707285169Scy set_sys_leap(LEAP_NOTINSYNC); 470854359Sroberto sys_stratum = STRATUM_UNSPEC; 4709132454Sroberto memcpy(&sys_refid, "INIT", 4); 4710280849Scy sys_peer = NULL; 471154359Sroberto sys_rootdelay = 0; 4712280849Scy sys_rootdisp = 0; 471354359Sroberto L_CLR(&sys_reftime); 4714280849Scy sys_jitter = 0; 4715280849Scy measure_precision(); 4716280849Scy get_systime(&dummy); 471782505Sroberto sys_survivors = 0; 4718132454Sroberto sys_manycastserver = 0; 471954359Sroberto sys_bclient = 0; 4720298695Sdelphij sys_bdelay = BDELAY_DEFAULT; /*[Bug 3031] delay cutoff */ 472154359Sroberto sys_authenticate = 1; 4722280849Scy sys_stattime = current_time; 4723280849Scy orphwait = current_time + sys_orphwait; 4724132454Sroberto proto_clr_stats(); 4725132454Sroberto for (i = 0; i < MAX_TTL; i++) { 4726132454Sroberto sys_ttl[i] = (u_char)((i * 256) / MAX_TTL); 4727132454Sroberto sys_ttlmax = i; 4728132454Sroberto } 4729280849Scy hardpps_enable = 0; 473054359Sroberto stats_control = 1; 473154359Sroberto} 473254359Sroberto 473354359Sroberto 473454359Sroberto/* 473554359Sroberto * proto_config - configure the protocol module 473654359Sroberto */ 473754359Srobertovoid 473854359Srobertoproto_config( 4739132454Sroberto int item, 4740132454Sroberto u_long value, 4741132454Sroberto double dvalue, 4742280849Scy sockaddr_u *svalue 474354359Sroberto ) 474454359Sroberto{ 474554359Sroberto /* 474654359Sroberto * Figure out what he wants to change, then do it 474754359Sroberto */ 4748280849Scy DPRINTF(2, ("proto_config: code %d value %lu dvalue %lf\n", 4749280849Scy item, value, dvalue)); 4750280849Scy 475154359Sroberto switch (item) { 4752132454Sroberto 4753132454Sroberto /* 4754280849Scy * enable and disable commands - arguments are Boolean. 4755132454Sroberto */ 4756280849Scy case PROTO_AUTHENTICATE: /* authentication (auth) */ 4757280849Scy sys_authenticate = value; 475854359Sroberto break; 475954359Sroberto 4760280849Scy case PROTO_BROADCLIENT: /* broadcast client (bclient) */ 4761280849Scy sys_bclient = (int)value; 4762280849Scy if (sys_bclient == 0) 4763280849Scy io_unsetbclient(); 4764280849Scy else 4765280849Scy io_setbclient(); 476654359Sroberto break; 476754359Sroberto 4768280849Scy#ifdef REFCLOCK 4769280849Scy case PROTO_CAL: /* refclock calibrate (calibrate) */ 4770280849Scy cal_enable = value; 4771280849Scy break; 4772280849Scy#endif /* REFCLOCK */ 4773280849Scy 4774280849Scy case PROTO_KERNEL: /* kernel discipline (kernel) */ 4775280849Scy select_loop(value); 4776280849Scy break; 4777280849Scy 4778280849Scy case PROTO_MONITOR: /* monitoring (monitor) */ 477954359Sroberto if (value) 478054359Sroberto mon_start(MON_ON); 4781285169Scy else { 478254359Sroberto mon_stop(MON_ON); 4783285169Scy if (mon_enabled) 4784285169Scy msyslog(LOG_WARNING, 4785285169Scy "restrict: 'monitor' cannot be disabled while 'limited' is enabled"); 4786285169Scy } 478754359Sroberto break; 478854359Sroberto 4789280849Scy case PROTO_NTP: /* NTP discipline (ntp) */ 4790280849Scy ntp_enable = value; 479154359Sroberto break; 479254359Sroberto 4793280849Scy case PROTO_MODE7: /* mode7 management (ntpdc) */ 4794280849Scy ntp_mode7 = value; 479554359Sroberto break; 479654359Sroberto 4797280849Scy case PROTO_PPS: /* PPS discipline (pps) */ 4798280849Scy hardpps_enable = value; 4799182007Sroberto break; 4800182007Sroberto 4801280849Scy case PROTO_FILEGEN: /* statistics (stats) */ 4802280849Scy stats_control = value; 480354359Sroberto break; 480454359Sroberto 4805132454Sroberto /* 4806280849Scy * tos command - arguments are double, sometimes cast to int 4807132454Sroberto */ 4808309007Sdelphij 4809309007Sdelphij case PROTO_BCPOLLBSTEP: /* Broadcast Poll Backstep gate (bcpollbstep) */ 4810309007Sdelphij sys_bcpollbstep = (u_char)dvalue; 4811309007Sdelphij break; 4812309007Sdelphij 4813280849Scy case PROTO_BEACON: /* manycast beacon (beacon) */ 4814280849Scy sys_beacon = (int)dvalue; 481554359Sroberto break; 481654359Sroberto 4817280849Scy case PROTO_BROADDELAY: /* default broadcast delay (bdelay) */ 4818298695Sdelphij sys_bdelay = (dvalue ? dvalue : BDELAY_DEFAULT); 481954359Sroberto break; 482054359Sroberto 4821280849Scy case PROTO_CEILING: /* stratum ceiling (ceiling) */ 4822280849Scy sys_ceiling = (int)dvalue; 4823132454Sroberto break; 4824132454Sroberto 4825280849Scy case PROTO_COHORT: /* cohort switch (cohort) */ 4826280849Scy sys_cohort = (int)dvalue; 482754359Sroberto break; 482854359Sroberto 4829280849Scy case PROTO_FLOOR: /* stratum floor (floor) */ 4830280849Scy sys_floor = (int)dvalue; 483182505Sroberto break; 483282505Sroberto 4833280849Scy case PROTO_MAXCLOCK: /* maximum candidates (maxclock) */ 4834182007Sroberto sys_maxclock = (int)dvalue; 4835132454Sroberto break; 4836132454Sroberto 4837280849Scy case PROTO_MAXDIST: /* select threshold (maxdist) */ 4838280849Scy sys_maxdist = dvalue; 4839132454Sroberto break; 4840132454Sroberto 4841280849Scy case PROTO_CALLDELAY: /* modem call delay (mdelay) */ 4842280849Scy break; /* NOT USED */ 4843132454Sroberto 4844280849Scy case PROTO_MINCLOCK: /* minimum candidates (minclock) */ 4845280849Scy sys_minclock = (int)dvalue; 4846132454Sroberto break; 4847132454Sroberto 4848280849Scy case PROTO_MINDISP: /* minimum distance (mindist) */ 4849280849Scy sys_mindisp = dvalue; 4850182007Sroberto break; 4851182007Sroberto 4852280849Scy case PROTO_MINSANE: /* minimum survivors (minsane) */ 4853280849Scy sys_minsane = (int)dvalue; 4854132454Sroberto break; 4855182007Sroberto 4856280849Scy case PROTO_ORPHAN: /* orphan stratum (orphan) */ 4857280849Scy sys_orphan = (int)dvalue; 4858182007Sroberto break; 4859182007Sroberto 4860280849Scy case PROTO_ORPHWAIT: /* orphan wait (orphwait) */ 4861280849Scy orphwait -= sys_orphwait; 4862280849Scy sys_orphwait = (int)dvalue; 4863280849Scy orphwait += sys_orphwait; 4864182007Sroberto break; 4865182007Sroberto 4866182007Sroberto /* 4867280849Scy * Miscellaneous commands 4868182007Sroberto */ 4869280849Scy case PROTO_MULTICAST_ADD: /* add group address */ 4870280849Scy if (svalue != NULL) 4871280849Scy io_multicast_add(svalue); 4872280849Scy sys_bclient = 1; 4873182007Sroberto break; 4874182007Sroberto 4875280849Scy case PROTO_MULTICAST_DEL: /* delete group address */ 4876280849Scy if (svalue != NULL) 4877280849Scy io_multicast_del(svalue); 4878132454Sroberto break; 4879132454Sroberto 4880294554Sdelphij /* 4881301247Sdelphij * Peer_clear Early policy choices 4882301247Sdelphij */ 4883301247Sdelphij 4884301247Sdelphij case PROTO_PCEDIGEST: /* Digest */ 4885301247Sdelphij peer_clear_digest_early = value; 4886301247Sdelphij break; 4887301247Sdelphij 4888301247Sdelphij /* 4889294554Sdelphij * Unpeer Early policy choices 4890294554Sdelphij */ 4891294554Sdelphij 4892294554Sdelphij case PROTO_UECRYPTO: /* Crypto */ 4893294554Sdelphij unpeer_crypto_early = value; 4894294554Sdelphij break; 4895294554Sdelphij 4896294554Sdelphij case PROTO_UECRYPTONAK: /* Crypto_NAK */ 4897294554Sdelphij unpeer_crypto_nak_early = value; 4898294554Sdelphij break; 4899294554Sdelphij 4900294554Sdelphij case PROTO_UEDIGEST: /* Digest */ 4901294554Sdelphij unpeer_digest_early = value; 4902294554Sdelphij break; 4903294554Sdelphij 490456749Sroberto default: 4905280849Scy msyslog(LOG_NOTICE, 4906280849Scy "proto: unsupported option %d", item); 490754359Sroberto } 490854359Sroberto} 490954359Sroberto 491054359Sroberto 491154359Sroberto/* 491254359Sroberto * proto_clr_stats - clear protocol stat counters 491354359Sroberto */ 491454359Srobertovoid 491554359Srobertoproto_clr_stats(void) 491654359Sroberto{ 4917132454Sroberto sys_stattime = current_time; 4918132454Sroberto sys_received = 0; 4919132454Sroberto sys_processed = 0; 4920280849Scy sys_newversion = 0; 4921280849Scy sys_oldversion = 0; 4922280849Scy sys_declined = 0; 4923132454Sroberto sys_restricted = 0; 492454359Sroberto sys_badlength = 0; 492554359Sroberto sys_badauth = 0; 492654359Sroberto sys_limitrejected = 0; 4927280849Scy sys_kodsent = 0; 492854359Sroberto} 4929