1/* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * The User Datagram Protocol (UDP). 7 * 8 * Version: $Id: udp.c,v 1.1.1.1 2007/08/03 18:53:51 Exp $ 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Arnt Gulbrandsen, <agulbra@nvg.unit.no> 13 * Alan Cox, <Alan.Cox@linux.org> 14 * Hirokazu Takahashi, <taka@valinux.co.jp> 15 * 16 * Fixes: 17 * Alan Cox : verify_area() calls 18 * Alan Cox : stopped close while in use off icmp 19 * messages. Not a fix but a botch that 20 * for udp at least is 'valid'. 21 * Alan Cox : Fixed icmp handling properly 22 * Alan Cox : Correct error for oversized datagrams 23 * Alan Cox : Tidied select() semantics. 24 * Alan Cox : udp_err() fixed properly, also now 25 * select and read wake correctly on errors 26 * Alan Cox : udp_send verify_area moved to avoid mem leak 27 * Alan Cox : UDP can count its memory 28 * Alan Cox : send to an unknown connection causes 29 * an ECONNREFUSED off the icmp, but 30 * does NOT close. 31 * Alan Cox : Switched to new sk_buff handlers. No more backlog! 32 * Alan Cox : Using generic datagram code. Even smaller and the PEEK 33 * bug no longer crashes it. 34 * Fred Van Kempen : Net2e support for sk->broadcast. 35 * Alan Cox : Uses skb_free_datagram 36 * Alan Cox : Added get/set sockopt support. 37 * Alan Cox : Broadcasting without option set returns EACCES. 38 * Alan Cox : No wakeup calls. Instead we now use the callbacks. 39 * Alan Cox : Use ip_tos and ip_ttl 40 * Alan Cox : SNMP Mibs 41 * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support. 42 * Matt Dillon : UDP length checks. 43 * Alan Cox : Smarter af_inet used properly. 44 * Alan Cox : Use new kernel side addressing. 45 * Alan Cox : Incorrect return on truncated datagram receive. 46 * Arnt Gulbrandsen : New udp_send and stuff 47 * Alan Cox : Cache last socket 48 * Alan Cox : Route cache 49 * Jon Peatfield : Minor efficiency fix to sendto(). 50 * Mike Shaver : RFC1122 checks. 51 * Alan Cox : Nonblocking error fix. 52 * Willy Konynenberg : Transparent proxying support. 53 * Mike McLagan : Routing by source 54 * David S. Miller : New socket lookup architecture. 55 * Last socket cache retained as it 56 * does have a high hit rate. 57 * Olaf Kirch : Don't linearise iovec on sendmsg. 58 * Andi Kleen : Some cleanups, cache destination entry 59 * for connect. 60 * Vitaly E. Lavrov : Transparent proxy revived after year coma. 61 * Melvin Smith : Check msg_name not msg_namelen in sendto(), 62 * return ENOTCONN for unconnected sockets (POSIX) 63 * Janos Farkas : don't deliver multi/broadcasts to a different 64 * bound-to-device socket 65 * Hirokazu Takahashi : HW checksumming for outgoing UDP 66 * datagrams. 67 * Hirokazu Takahashi : sendfile() on UDP works now. 68 * Arnaldo C. Melo : convert /proc/net/udp to seq_file 69 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which 70 * Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind 71 * a single port at the same time. 72 * Derek Atkins <derek@ihtfp.com>: Add Encapulation Support 73 * 74 * 75 * This program is free software; you can redistribute it and/or 76 * modify it under the terms of the GNU General Public License 77 * as published by the Free Software Foundation; either version 78 * 2 of the License, or (at your option) any later version. 79 */ 80 81#include <asm/system.h> 82#include <asm/uaccess.h> 83#include <asm/ioctls.h> 84#include <linux/types.h> 85#include <linux/fcntl.h> 86#include <linux/module.h> 87#include <linux/socket.h> 88#include <linux/sockios.h> 89#include <linux/igmp.h> 90#include <linux/in.h> 91#include <linux/errno.h> 92#include <linux/timer.h> 93#include <linux/mm.h> 94#include <linux/inet.h> 95#include <linux/netdevice.h> 96#include <net/tcp_states.h> 97#include <linux/skbuff.h> 98#include <linux/proc_fs.h> 99#include <linux/seq_file.h> 100#include <net/icmp.h> 101#include <net/route.h> 102#include <net/checksum.h> 103#include <net/xfrm.h> 104#include "udp_impl.h" 105 106/* 107 * Snmp MIB for the UDP layer 108 */ 109 110DEFINE_SNMP_STAT(struct udp_mib, udp_statistics) __read_mostly; 111 112struct hlist_head udp_hash[UDP_HTABLE_SIZE]; 113DEFINE_RWLOCK(udp_hash_lock); 114 115static int udp_port_rover; 116 117static inline int __udp_lib_lport_inuse(__u16 num, struct hlist_head udptable[]) 118{ 119 struct sock *sk; 120 struct hlist_node *node; 121 122 sk_for_each(sk, node, &udptable[num & (UDP_HTABLE_SIZE - 1)]) 123 if (sk->sk_hash == num) 124 return 1; 125 return 0; 126} 127 128/** 129 * __udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6 130 * 131 * @sk: socket struct in question 132 * @snum: port number to look up 133 * @udptable: hash list table, must be of UDP_HTABLE_SIZE 134 * @port_rover: pointer to record of last unallocated port 135 * @saddr_comp: AF-dependent comparison of bound local IP addresses 136 */ 137int __udp_lib_get_port(struct sock *sk, unsigned short snum, 138 struct hlist_head udptable[], int *port_rover, 139 int (*saddr_comp)(const struct sock *sk1, 140 const struct sock *sk2 ) ) 141{ 142 struct hlist_node *node; 143 struct hlist_head *head; 144 struct sock *sk2; 145 int error = 1; 146 147 write_lock_bh(&udp_hash_lock); 148 if (snum == 0) { 149 int best_size_so_far, best, result, i; 150 151 if (*port_rover > sysctl_local_port_range[1] || 152 *port_rover < sysctl_local_port_range[0]) 153 *port_rover = sysctl_local_port_range[0]; 154 best_size_so_far = 32767; 155 best = result = *port_rover; 156 for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) { 157 int size; 158 159 head = &udptable[result & (UDP_HTABLE_SIZE - 1)]; 160 if (hlist_empty(head)) { 161 if (result > sysctl_local_port_range[1]) 162 result = sysctl_local_port_range[0] + 163 ((result - sysctl_local_port_range[0]) & 164 (UDP_HTABLE_SIZE - 1)); 165 goto gotit; 166 } 167 size = 0; 168 sk_for_each(sk2, node, head) { 169 if (++size >= best_size_so_far) 170 goto next; 171 } 172 best_size_so_far = size; 173 best = result; 174 next: 175 ; 176 } 177 result = best; 178 for (i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; 179 i++, result += UDP_HTABLE_SIZE) { 180 if (result > sysctl_local_port_range[1]) 181 result = sysctl_local_port_range[0] 182 + ((result - sysctl_local_port_range[0]) & 183 (UDP_HTABLE_SIZE - 1)); 184 if (! __udp_lib_lport_inuse(result, udptable)) 185 break; 186 } 187 if (i >= (1 << 16) / UDP_HTABLE_SIZE) 188 goto fail; 189gotit: 190 *port_rover = snum = result; 191 } else { 192 head = &udptable[snum & (UDP_HTABLE_SIZE - 1)]; 193 194 sk_for_each(sk2, node, head) 195 if (sk2->sk_hash == snum && 196 sk2 != sk && 197 (!sk2->sk_reuse || !sk->sk_reuse) && 198 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if 199 || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && 200 (*saddr_comp)(sk, sk2) ) 201 goto fail; 202 } 203 inet_sk(sk)->num = snum; 204 sk->sk_hash = snum; 205 if (sk_unhashed(sk)) { 206 head = &udptable[snum & (UDP_HTABLE_SIZE - 1)]; 207 sk_add_node(sk, head); 208 sock_prot_inc_use(sk->sk_prot); 209 } 210 error = 0; 211fail: 212 write_unlock_bh(&udp_hash_lock); 213 return error; 214} 215 216int udp_get_port(struct sock *sk, unsigned short snum, 217 int (*scmp)(const struct sock *, const struct sock *)) 218{ 219 return __udp_lib_get_port(sk, snum, udp_hash, &udp_port_rover, scmp); 220} 221 222int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2) 223{ 224 struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2); 225 226 return ( !ipv6_only_sock(sk2) && 227 (!inet1->rcv_saddr || !inet2->rcv_saddr || 228 inet1->rcv_saddr == inet2->rcv_saddr )); 229} 230 231static inline int udp_v4_get_port(struct sock *sk, unsigned short snum) 232{ 233 return udp_get_port(sk, snum, ipv4_rcv_saddr_equal); 234} 235 236/* UDP is nearly always wildcards out the wazoo, it makes no sense to try 237 * harder than this. -DaveM 238 */ 239static struct sock *__udp4_lib_lookup(__be32 saddr, __be16 sport, 240 __be32 daddr, __be16 dport, 241 int dif, struct hlist_head udptable[]) 242{ 243 struct sock *sk, *result = NULL; 244 struct hlist_node *node; 245 unsigned short hnum = ntohs(dport); 246 int badness = -1; 247 248 read_lock(&udp_hash_lock); 249 sk_for_each(sk, node, &udptable[hnum & (UDP_HTABLE_SIZE - 1)]) { 250 struct inet_sock *inet = inet_sk(sk); 251 252 if (sk->sk_hash == hnum && !ipv6_only_sock(sk)) { 253 int score = (sk->sk_family == PF_INET ? 1 : 0); 254 if (inet->rcv_saddr) { 255 if (inet->rcv_saddr != daddr) 256 continue; 257 score+=2; 258 } 259 if (inet->daddr) { 260 if (inet->daddr != saddr) 261 continue; 262 score+=2; 263 } 264 if (inet->dport) { 265 if (inet->dport != sport) 266 continue; 267 score+=2; 268 } 269 if (sk->sk_bound_dev_if) { 270 if (sk->sk_bound_dev_if != dif) 271 continue; 272 score+=2; 273 } 274 if (score == 9) { 275 result = sk; 276 break; 277 } else if (score > badness) { 278 result = sk; 279 badness = score; 280 } 281 } 282 } 283 if (result) 284 sock_hold(result); 285 read_unlock(&udp_hash_lock); 286 return result; 287} 288 289static inline struct sock *udp_v4_mcast_next(struct sock *sk, 290 __be16 loc_port, __be32 loc_addr, 291 __be16 rmt_port, __be32 rmt_addr, 292 int dif) 293{ 294 struct hlist_node *node; 295 struct sock *s = sk; 296 unsigned short hnum = ntohs(loc_port); 297 298 sk_for_each_from(s, node) { 299 struct inet_sock *inet = inet_sk(s); 300 301 if (s->sk_hash != hnum || 302 (inet->daddr && inet->daddr != rmt_addr) || 303 (inet->dport != rmt_port && inet->dport) || 304 (inet->rcv_saddr && inet->rcv_saddr != loc_addr) || 305 ipv6_only_sock(s) || 306 (s->sk_bound_dev_if && s->sk_bound_dev_if != dif)) 307 continue; 308 if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif)) 309 continue; 310 goto found; 311 } 312 s = NULL; 313found: 314 return s; 315} 316 317/* 318 * This routine is called by the ICMP module when it gets some 319 * sort of error condition. If err < 0 then the socket should 320 * be closed and the error returned to the user. If err > 0 321 * it's just the icmp type << 8 | icmp code. 322 * Header points to the ip header of the error packet. We move 323 * on past this. Then (as it used to claim before adjustment) 324 * header points to the first 8 bytes of the udp header. We need 325 * to find the appropriate port. 326 */ 327 328void __udp4_lib_err(struct sk_buff *skb, u32 info, struct hlist_head udptable[]) 329{ 330 struct inet_sock *inet; 331 struct iphdr *iph = (struct iphdr*)skb->data; 332 struct udphdr *uh = (struct udphdr*)(skb->data+(iph->ihl<<2)); 333 const int type = icmp_hdr(skb)->type; 334 const int code = icmp_hdr(skb)->code; 335 struct sock *sk; 336 int harderr; 337 int err; 338 339 sk = __udp4_lib_lookup(iph->daddr, uh->dest, iph->saddr, uh->source, 340 skb->dev->ifindex, udptable ); 341 if (sk == NULL) { 342 ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); 343 return; /* No socket for error */ 344 } 345 346 err = 0; 347 harderr = 0; 348 inet = inet_sk(sk); 349 350 switch (type) { 351 default: 352 case ICMP_TIME_EXCEEDED: 353 err = EHOSTUNREACH; 354 break; 355 case ICMP_SOURCE_QUENCH: 356 goto out; 357 case ICMP_PARAMETERPROB: 358 err = EPROTO; 359 harderr = 1; 360 break; 361 case ICMP_DEST_UNREACH: 362 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ 363 if (inet->pmtudisc != IP_PMTUDISC_DONT) { 364 err = EMSGSIZE; 365 harderr = 1; 366 break; 367 } 368 goto out; 369 } 370 err = EHOSTUNREACH; 371 if (code <= NR_ICMP_UNREACH) { 372 harderr = icmp_err_convert[code].fatal; 373 err = icmp_err_convert[code].errno; 374 } 375 break; 376 } 377 378 /* 379 * RFC1122: OK. Passes ICMP errors back to application, as per 380 * 4.1.3.3. 381 */ 382 if (!inet->recverr) { 383 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 384 goto out; 385 } else { 386 ip_icmp_error(sk, skb, err, uh->dest, info, (u8*)(uh+1)); 387 } 388 sk->sk_err = err; 389 sk->sk_error_report(sk); 390out: 391 sock_put(sk); 392} 393 394void udp_err(struct sk_buff *skb, u32 info) 395{ 396 return __udp4_lib_err(skb, info, udp_hash); 397} 398 399/* 400 * Throw away all pending data and cancel the corking. Socket is locked. 401 */ 402static void udp_flush_pending_frames(struct sock *sk) 403{ 404 struct udp_sock *up = udp_sk(sk); 405 406 if (up->pending) { 407 up->len = 0; 408 up->pending = 0; 409 ip_flush_pending_frames(sk); 410 } 411} 412 413/** 414 * udp4_hwcsum_outgoing - handle outgoing HW checksumming 415 * @sk: socket we are sending on 416 * @skb: sk_buff containing the filled-in UDP header 417 * (checksum field must be zeroed out) 418 */ 419static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, 420 __be32 src, __be32 dst, int len ) 421{ 422 unsigned int offset; 423 struct udphdr *uh = udp_hdr(skb); 424 __wsum csum = 0; 425 426 if (skb_queue_len(&sk->sk_write_queue) == 1) { 427 /* 428 * Only one fragment on the socket. 429 */ 430 skb->csum_start = skb_transport_header(skb) - skb->head; 431 skb->csum_offset = offsetof(struct udphdr, check); 432 uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0); 433 } else { 434 /* 435 * HW-checksum won't work as there are two or more 436 * fragments on the socket so that all csums of sk_buffs 437 * should be together 438 */ 439 offset = skb_transport_offset(skb); 440 skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); 441 442 skb->ip_summed = CHECKSUM_NONE; 443 444 skb_queue_walk(&sk->sk_write_queue, skb) { 445 csum = csum_add(csum, skb->csum); 446 } 447 448 uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum); 449 if (uh->check == 0) 450 uh->check = CSUM_MANGLED_0; 451 } 452} 453 454/* 455 * Push out all pending data as one UDP datagram. Socket is locked. 456 */ 457static int udp_push_pending_frames(struct sock *sk) 458{ 459 struct udp_sock *up = udp_sk(sk); 460 struct inet_sock *inet = inet_sk(sk); 461 struct flowi *fl = &inet->cork.fl; 462 struct sk_buff *skb; 463 struct udphdr *uh; 464 int err = 0; 465 __wsum csum = 0; 466 467 /* Grab the skbuff where UDP header space exists. */ 468 if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) 469 goto out; 470 471 /* 472 * Create a UDP header 473 */ 474 uh = udp_hdr(skb); 475 uh->source = fl->fl_ip_sport; 476 uh->dest = fl->fl_ip_dport; 477 uh->len = htons(up->len); 478 uh->check = 0; 479 480 if (up->pcflag) /* UDP-Lite */ 481 csum = udplite_csum_outgoing(sk, skb); 482 483 else if (sk->sk_no_check == UDP_CSUM_NOXMIT) { /* UDP csum disabled */ 484 485 skb->ip_summed = CHECKSUM_NONE; 486 goto send; 487 488 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ 489 490 udp4_hwcsum_outgoing(sk, skb, fl->fl4_src,fl->fl4_dst, up->len); 491 goto send; 492 493 } else /* `normal' UDP */ 494 csum = udp_csum_outgoing(sk, skb); 495 496 /* add protocol-dependent pseudo-header */ 497 uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, up->len, 498 sk->sk_protocol, csum ); 499 if (uh->check == 0) 500 uh->check = CSUM_MANGLED_0; 501 502send: 503 err = ip_push_pending_frames(sk); 504out: 505 up->len = 0; 506 up->pending = 0; 507 return err; 508} 509 510int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 511 size_t len) 512{ 513 struct inet_sock *inet = inet_sk(sk); 514 struct udp_sock *up = udp_sk(sk); 515 int ulen = len; 516 struct ipcm_cookie ipc; 517 struct rtable *rt = NULL; 518 int free = 0; 519 int connected = 0; 520 __be32 daddr, faddr, saddr; 521 __be16 dport; 522 u8 tos; 523 int err, is_udplite = up->pcflag; 524 int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; 525 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); 526 527 if (len > 0xFFFF) 528 return -EMSGSIZE; 529 530 /* 531 * Check the flags. 532 */ 533 534 if (msg->msg_flags&MSG_OOB) /* Mirror BSD error message compatibility */ 535 return -EOPNOTSUPP; 536 537 ipc.opt = NULL; 538 539 if (up->pending) { 540 /* 541 * There are pending frames. 542 * The socket lock must be held while it's corked. 543 */ 544 lock_sock(sk); 545 if (likely(up->pending)) { 546 if (unlikely(up->pending != AF_INET)) { 547 release_sock(sk); 548 return -EINVAL; 549 } 550 goto do_append_data; 551 } 552 release_sock(sk); 553 } 554 ulen += sizeof(struct udphdr); 555 556 /* 557 * Get and verify the address. 558 */ 559 if (msg->msg_name) { 560 struct sockaddr_in * usin = (struct sockaddr_in*)msg->msg_name; 561 if (msg->msg_namelen < sizeof(*usin)) 562 return -EINVAL; 563 if (usin->sin_family != AF_INET) { 564 if (usin->sin_family != AF_UNSPEC) 565 return -EAFNOSUPPORT; 566 } 567 568 daddr = usin->sin_addr.s_addr; 569 dport = usin->sin_port; 570 if (dport == 0) 571 return -EINVAL; 572 } else { 573 if (sk->sk_state != TCP_ESTABLISHED) 574 return -EDESTADDRREQ; 575 daddr = inet->daddr; 576 dport = inet->dport; 577 /* Open fast path for connected socket. 578 Route will not be used, if at least one option is set. 579 */ 580 connected = 1; 581 } 582 ipc.addr = inet->saddr; 583 584 ipc.oif = sk->sk_bound_dev_if; 585 if (msg->msg_controllen) { 586 err = ip_cmsg_send(msg, &ipc); 587 if (err) 588 return err; 589 if (ipc.opt) 590 free = 1; 591 connected = 0; 592 } 593 if (!ipc.opt) 594 ipc.opt = inet->opt; 595 596 saddr = ipc.addr; 597 ipc.addr = faddr = daddr; 598 599 if (ipc.opt && ipc.opt->srr) { 600 if (!daddr) 601 return -EINVAL; 602 faddr = ipc.opt->faddr; 603 connected = 0; 604 } 605 tos = RT_TOS(inet->tos); 606 if (sock_flag(sk, SOCK_LOCALROUTE) || 607 (msg->msg_flags & MSG_DONTROUTE) || 608 (ipc.opt && ipc.opt->is_strictroute)) { 609 tos |= RTO_ONLINK; 610 connected = 0; 611 } 612 613 if (MULTICAST(daddr)) { 614 if (!ipc.oif) 615 ipc.oif = inet->mc_index; 616 if (!saddr) 617 saddr = inet->mc_addr; 618 connected = 0; 619 } 620 621 if (connected) 622 rt = (struct rtable*)sk_dst_check(sk, 0); 623 624 if (rt == NULL) { 625 struct flowi fl = { .oif = ipc.oif, 626 .nl_u = { .ip4_u = 627 { .daddr = faddr, 628 .saddr = saddr, 629 .tos = tos } }, 630 .proto = sk->sk_protocol, 631 .uli_u = { .ports = 632 { .sport = inet->sport, 633 .dport = dport } } }; 634 security_sk_classify_flow(sk, &fl); 635 err = ip_route_output_flow(&rt, &fl, sk, 1); 636 if (err) { 637 if (err == -ENETUNREACH) 638 IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); 639 goto out; 640 } 641 642 err = -EACCES; 643 if ((rt->rt_flags & RTCF_BROADCAST) && 644 !sock_flag(sk, SOCK_BROADCAST)) 645 goto out; 646 if (connected) 647 sk_dst_set(sk, dst_clone(&rt->u.dst)); 648 } 649 650 if (msg->msg_flags&MSG_CONFIRM) 651 goto do_confirm; 652back_from_confirm: 653 654 saddr = rt->rt_src; 655 if (!ipc.addr) 656 daddr = ipc.addr = rt->rt_dst; 657 658 lock_sock(sk); 659 if (unlikely(up->pending)) { 660 /* The socket is already corked while preparing it. */ 661 /* ... which is an evident application bug. --ANK */ 662 release_sock(sk); 663 664 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 2\n"); 665 err = -EINVAL; 666 goto out; 667 } 668 /* 669 * Now cork the socket to pend data. 670 */ 671 inet->cork.fl.fl4_dst = daddr; 672 inet->cork.fl.fl_ip_dport = dport; 673 inet->cork.fl.fl4_src = saddr; 674 inet->cork.fl.fl_ip_sport = inet->sport; 675 up->pending = AF_INET; 676 677do_append_data: 678 up->len += ulen; 679 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; 680 err = ip_append_data(sk, getfrag, msg->msg_iov, ulen, 681 sizeof(struct udphdr), &ipc, rt, 682 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); 683 if (err) 684 udp_flush_pending_frames(sk); 685 else if (!corkreq) 686 err = udp_push_pending_frames(sk); 687 else if (unlikely(skb_queue_empty(&sk->sk_write_queue))) 688 up->pending = 0; 689 release_sock(sk); 690 691out: 692 ip_rt_put(rt); 693 if (free) 694 kfree(ipc.opt); 695 if (!err) { 696 UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS, is_udplite); 697 return len; 698 } 699 /* 700 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting 701 * ENOBUFS might not be good (it's not tunable per se), but otherwise 702 * we don't have a good statistic (IpOutDiscards but it can be too many 703 * things). We could add another new stat but at least for now that 704 * seems like overkill. 705 */ 706 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { 707 UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS, is_udplite); 708 } 709 return err; 710 711do_confirm: 712 dst_confirm(&rt->u.dst); 713 if (!(msg->msg_flags&MSG_PROBE) || len) 714 goto back_from_confirm; 715 err = 0; 716 goto out; 717} 718 719int udp_sendpage(struct sock *sk, struct page *page, int offset, 720 size_t size, int flags) 721{ 722 struct udp_sock *up = udp_sk(sk); 723 int ret; 724 725 if (!up->pending) { 726 struct msghdr msg = { .msg_flags = flags|MSG_MORE }; 727 728 /* Call udp_sendmsg to specify destination address which 729 * sendpage interface can't pass. 730 * This will succeed only when the socket is connected. 731 */ 732 ret = udp_sendmsg(NULL, sk, &msg, 0); 733 if (ret < 0) 734 return ret; 735 } 736 737 lock_sock(sk); 738 739 if (unlikely(!up->pending)) { 740 release_sock(sk); 741 742 LIMIT_NETDEBUG(KERN_DEBUG "udp cork app bug 3\n"); 743 return -EINVAL; 744 } 745 746 ret = ip_append_page(sk, page, offset, size, flags); 747 if (ret == -EOPNOTSUPP) { 748 release_sock(sk); 749 return sock_no_sendpage(sk->sk_socket, page, offset, 750 size, flags); 751 } 752 if (ret < 0) { 753 udp_flush_pending_frames(sk); 754 goto out; 755 } 756 757 up->len += size; 758 if (!(up->corkflag || (flags&MSG_MORE))) 759 ret = udp_push_pending_frames(sk); 760 if (!ret) 761 ret = size; 762out: 763 release_sock(sk); 764 return ret; 765} 766 767/* 768 * IOCTL requests applicable to the UDP protocol 769 */ 770 771int udp_ioctl(struct sock *sk, int cmd, unsigned long arg) 772{ 773 switch (cmd) { 774 case SIOCOUTQ: 775 { 776 int amount = atomic_read(&sk->sk_wmem_alloc); 777 return put_user(amount, (int __user *)arg); 778 } 779 780 case SIOCINQ: 781 { 782 struct sk_buff *skb; 783 unsigned long amount; 784 785 amount = 0; 786 spin_lock_bh(&sk->sk_receive_queue.lock); 787 skb = skb_peek(&sk->sk_receive_queue); 788 if (skb != NULL) { 789 /* 790 * We will only return the amount 791 * of this packet since that is all 792 * that will be read. 793 */ 794 amount = skb->len - sizeof(struct udphdr); 795 } 796 spin_unlock_bh(&sk->sk_receive_queue.lock); 797 return put_user(amount, (int __user *)arg); 798 } 799 800 default: 801 return -ENOIOCTLCMD; 802 } 803 804 return 0; 805} 806 807/* 808 * This should be easy, if there is something there we 809 * return it, otherwise we block. 810 */ 811 812int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 813 size_t len, int noblock, int flags, int *addr_len) 814{ 815 struct inet_sock *inet = inet_sk(sk); 816 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; 817 struct sk_buff *skb; 818 unsigned int ulen, copied; 819 int err; 820 int is_udplite = IS_UDPLITE(sk); 821 822 /* 823 * Check any passed addresses 824 */ 825 if (addr_len) 826 *addr_len=sizeof(*sin); 827 828 if (flags & MSG_ERRQUEUE) 829 return ip_recv_error(sk, msg, len); 830 831try_again: 832 skb = skb_recv_datagram(sk, flags, noblock, &err); 833 if (!skb) 834 goto out; 835 836 ulen = skb->len - sizeof(struct udphdr); 837 copied = len; 838 if (copied > ulen) 839 copied = ulen; 840 else if (copied < ulen) 841 msg->msg_flags |= MSG_TRUNC; 842 843 /* 844 * If checksum is needed at all, try to do it while copying the 845 * data. If the data is truncated, or if we only want a partial 846 * coverage checksum (UDP-Lite), do it before the copy. 847 */ 848 849 if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) { 850 if (udp_lib_checksum_complete(skb)) 851 goto csum_copy_err; 852 } 853 854 if (skb_csum_unnecessary(skb)) 855 err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), 856 msg->msg_iov, copied ); 857 else { 858 err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); 859 860 if (err == -EINVAL) 861 goto csum_copy_err; 862 } 863 864 if (err) 865 goto out_free; 866 867 sock_recv_timestamp(msg, sk, skb); 868 869 /* Copy the address. */ 870 if (sin) 871 { 872 sin->sin_family = AF_INET; 873 sin->sin_port = udp_hdr(skb)->source; 874 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 875 memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); 876 } 877 if (inet->cmsg_flags) 878 ip_cmsg_recv(msg, skb); 879 880 err = copied; 881 if (flags & MSG_TRUNC) 882 err = ulen; 883 884out_free: 885 skb_free_datagram(sk, skb); 886out: 887 return err; 888 889csum_copy_err: 890 UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_udplite); 891 892 skb_kill_datagram(sk, skb, flags); 893 894 if (noblock) 895 return -EAGAIN; 896 goto try_again; 897} 898 899 900int udp_disconnect(struct sock *sk, int flags) 901{ 902 struct inet_sock *inet = inet_sk(sk); 903 /* 904 * 1003.1g - break association. 905 */ 906 907 sk->sk_state = TCP_CLOSE; 908 inet->daddr = 0; 909 inet->dport = 0; 910 sk->sk_bound_dev_if = 0; 911 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) 912 inet_reset_saddr(sk); 913 914 if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) { 915 sk->sk_prot->unhash(sk); 916 inet->sport = 0; 917 } 918 sk_dst_reset(sk); 919 return 0; 920} 921 922/* return: 923 * 1 if the UDP system should process it 924 * 0 if we should drop this packet 925 * -1 if it should get processed by xfrm4_rcv_encap 926 */ 927static int udp_encap_rcv(struct sock * sk, struct sk_buff *skb) 928{ 929#ifndef CONFIG_XFRM 930 return 1; 931#else 932 struct udp_sock *up = udp_sk(sk); 933 struct udphdr *uh; 934 struct iphdr *iph; 935 int iphlen, len; 936 937 __u8 *udpdata; 938 __be32 *udpdata32; 939 __u16 encap_type = up->encap_type; 940 941 /* if we're overly short, let UDP handle it */ 942 len = skb->len - sizeof(struct udphdr); 943 if (len <= 0) 944 return 1; 945 946 /* if this is not encapsulated socket, then just return now */ 947 if (!encap_type) 948 return 1; 949 950 /* If this is a paged skb, make sure we pull up 951 * whatever data we need to look at. */ 952 if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8))) 953 return 1; 954 955 /* Now we can get the pointers */ 956 uh = udp_hdr(skb); 957 udpdata = (__u8 *)uh + sizeof(struct udphdr); 958 udpdata32 = (__be32 *)udpdata; 959 960 switch (encap_type) { 961 default: 962 case UDP_ENCAP_ESPINUDP: 963 /* Check if this is a keepalive packet. If so, eat it. */ 964 if (len == 1 && udpdata[0] == 0xff) { 965 return 0; 966 } else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) { 967 /* ESP Packet without Non-ESP header */ 968 len = sizeof(struct udphdr); 969 } else 970 /* Must be an IKE packet.. pass it through */ 971 return 1; 972 break; 973 case UDP_ENCAP_ESPINUDP_NON_IKE: 974 /* Check if this is a keepalive packet. If so, eat it. */ 975 if (len == 1 && udpdata[0] == 0xff) { 976 return 0; 977 } else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) && 978 udpdata32[0] == 0 && udpdata32[1] == 0) { 979 980 /* ESP Packet with Non-IKE marker */ 981 len = sizeof(struct udphdr) + 2 * sizeof(u32); 982 } else 983 /* Must be an IKE packet.. pass it through */ 984 return 1; 985 break; 986 } 987 988 /* At this point we are sure that this is an ESPinUDP packet, 989 * so we need to remove 'len' bytes from the packet (the UDP 990 * header and optional ESP marker bytes) and then modify the 991 * protocol to ESP, and then call into the transform receiver. 992 */ 993 if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) 994 return 0; 995 996 /* Now we can update and verify the packet length... */ 997 iph = ip_hdr(skb); 998 iphlen = iph->ihl << 2; 999 iph->tot_len = htons(ntohs(iph->tot_len) - len); 1000 if (skb->len < iphlen + len) { 1001 /* packet is too small!?! */ 1002 return 0; 1003 } 1004 1005 /* pull the data buffer up to the ESP header and set the 1006 * transport header to point to ESP. Keep UDP on the stack 1007 * for later. 1008 */ 1009 __skb_pull(skb, len); 1010 skb_reset_transport_header(skb); 1011 1012 /* modify the protocol (it's ESP!) */ 1013 iph->protocol = IPPROTO_ESP; 1014 1015 /* and let the caller know to send this into the ESP processor... */ 1016 return -1; 1017#endif 1018} 1019 1020/* returns: 1021 * -1: error 1022 * 0: success 1023 * >0: "udp encap" protocol resubmission 1024 * 1025 * Note that in the success and error cases, the skb is assumed to 1026 * have either been requeued or freed. 1027 */ 1028int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) 1029{ 1030 struct udp_sock *up = udp_sk(sk); 1031 int rc; 1032 1033 /* 1034 * Charge it to the socket, dropping if the queue is full. 1035 */ 1036 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) 1037 goto drop; 1038 nf_reset(skb); 1039 1040 if (up->encap_type) { 1041 /* 1042 * This is an encapsulation socket, so let's see if this is 1043 * an encapsulated packet. 1044 * If it's a keepalive packet, then just eat it. 1045 * If it's an encapsulateed packet, then pass it to the 1046 * IPsec xfrm input and return the response 1047 * appropriately. Otherwise, just fall through and 1048 * pass this up the UDP socket. 1049 */ 1050 int ret; 1051 1052 ret = udp_encap_rcv(sk, skb); 1053 if (ret == 0) { 1054 /* Eat the packet .. */ 1055 kfree_skb(skb); 1056 return 0; 1057 } 1058 if (ret < 0) { 1059 /* process the ESP packet */ 1060 ret = xfrm4_rcv_encap(skb, up->encap_type); 1061 UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag); 1062 return -ret; 1063 } 1064 /* FALLTHROUGH -- it's a UDP Packet */ 1065 } 1066 1067 /* 1068 * UDP-Lite specific tests, ignored on UDP sockets 1069 */ 1070 if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { 1071 1072 /* 1073 * MIB statistics other than incrementing the error count are 1074 * disabled for the following two types of errors: these depend 1075 * on the application settings, not on the functioning of the 1076 * protocol stack as such. 1077 * 1078 * RFC 3828 here recommends (sec 3.3): "There should also be a 1079 * way ... to ... at least let the receiving application block 1080 * delivery of packets with coverage values less than a value 1081 * provided by the application." 1082 */ 1083 if (up->pcrlen == 0) { /* full coverage was set */ 1084 LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage " 1085 "%d while full coverage %d requested\n", 1086 UDP_SKB_CB(skb)->cscov, skb->len); 1087 goto drop; 1088 } 1089 /* The next case involves violating the min. coverage requested 1090 * by the receiver. This is subtle: if receiver wants x and x is 1091 * greater than the buffersize/MTU then receiver will complain 1092 * that it wants x while sender emits packets of smaller size y. 1093 * Therefore the above ...()->partial_cov statement is essential. 1094 */ 1095 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { 1096 LIMIT_NETDEBUG(KERN_WARNING 1097 "UDPLITE: coverage %d too small, need min %d\n", 1098 UDP_SKB_CB(skb)->cscov, up->pcrlen); 1099 goto drop; 1100 } 1101 } 1102 1103 if (sk->sk_filter) { 1104 if (udp_lib_checksum_complete(skb)) 1105 goto drop; 1106 } 1107 1108 if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) { 1109 /* Note that an ENOMEM error is charged twice */ 1110 if (rc == -ENOMEM) 1111 UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS, up->pcflag); 1112 goto drop; 1113 } 1114 1115 UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag); 1116 return 0; 1117 1118drop: 1119 UDP_INC_STATS_BH(UDP_MIB_INERRORS, up->pcflag); 1120 kfree_skb(skb); 1121 return -1; 1122} 1123 1124/* 1125 * Multicasts and broadcasts go to each listener. 1126 * 1127 * Note: called only from the BH handler context, 1128 * so we don't need to lock the hashes. 1129 */ 1130static int __udp4_lib_mcast_deliver(struct sk_buff *skb, 1131 struct udphdr *uh, 1132 __be32 saddr, __be32 daddr, 1133 struct hlist_head udptable[]) 1134{ 1135 struct sock *sk; 1136 int dif; 1137 1138 read_lock(&udp_hash_lock); 1139 sk = sk_head(&udptable[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]); 1140 dif = skb->dev->ifindex; 1141 sk = udp_v4_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif); 1142 if (sk) { 1143 struct sock *sknext = NULL; 1144 1145 do { 1146 struct sk_buff *skb1 = skb; 1147 1148 sknext = udp_v4_mcast_next(sk_next(sk), uh->dest, daddr, 1149 uh->source, saddr, dif); 1150 if (sknext) 1151 skb1 = skb_clone(skb, GFP_ATOMIC); 1152 1153 if (skb1) { 1154 int ret = udp_queue_rcv_skb(sk, skb1); 1155 if (ret > 0) 1156 /* we should probably re-process instead 1157 * of dropping packets here. */ 1158 kfree_skb(skb1); 1159 } 1160 sk = sknext; 1161 } while (sknext); 1162 } else 1163 kfree_skb(skb); 1164 read_unlock(&udp_hash_lock); 1165 return 0; 1166} 1167 1168/* Initialize UDP checksum. If exited with zero value (success), 1169 * CHECKSUM_UNNECESSARY means, that no more checks are required. 1170 * Otherwise, csum completion requires chacksumming packet body, 1171 * including udp header and folding it to skb->csum. 1172 */ 1173static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh, 1174 int proto) 1175{ 1176 const struct iphdr *iph; 1177 int err; 1178 1179 UDP_SKB_CB(skb)->partial_cov = 0; 1180 UDP_SKB_CB(skb)->cscov = skb->len; 1181 1182 if (proto == IPPROTO_UDPLITE) { 1183 err = udplite_checksum_init(skb, uh); 1184 if (err) 1185 return err; 1186 } 1187 1188 iph = ip_hdr(skb); 1189 if (uh->check == 0) { 1190 skb->ip_summed = CHECKSUM_UNNECESSARY; 1191 } else if (skb->ip_summed == CHECKSUM_COMPLETE) { 1192 if (!csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len, 1193 proto, skb->csum)) 1194 skb->ip_summed = CHECKSUM_UNNECESSARY; 1195 } 1196 if (!skb_csum_unnecessary(skb)) 1197 skb->csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, 1198 skb->len, proto, 0); 1199 /* Probably, we should checksum udp header (it should be in cache 1200 * in any case) and data in tiny packets (< rx copybreak). 1201 */ 1202 1203 return 0; 1204} 1205 1206/* 1207 * All we need to do is get the socket, and then do a checksum. 1208 */ 1209 1210int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[], 1211 int proto) 1212{ 1213 struct sock *sk; 1214 struct udphdr *uh = udp_hdr(skb); 1215 unsigned short ulen; 1216 struct rtable *rt = (struct rtable*)skb->dst; 1217 __be32 saddr = ip_hdr(skb)->saddr; 1218 __be32 daddr = ip_hdr(skb)->daddr; 1219 1220 /* 1221 * Validate the packet. 1222 */ 1223 if (!pskb_may_pull(skb, sizeof(struct udphdr))) 1224 goto drop; /* No space for header. */ 1225 1226 ulen = ntohs(uh->len); 1227 if (ulen > skb->len) 1228 goto short_packet; 1229 1230 if (proto == IPPROTO_UDP) { 1231 /* UDP validates ulen. */ 1232 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen)) 1233 goto short_packet; 1234 uh = udp_hdr(skb); 1235 } 1236 1237 if (udp4_csum_init(skb, uh, proto)) 1238 goto csum_error; 1239 1240 if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) 1241 return __udp4_lib_mcast_deliver(skb, uh, saddr, daddr, udptable); 1242 1243 sk = __udp4_lib_lookup(saddr, uh->source, daddr, uh->dest, 1244 skb->dev->ifindex, udptable ); 1245 1246 if (sk != NULL) { 1247 int ret = udp_queue_rcv_skb(sk, skb); 1248 sock_put(sk); 1249 1250 /* a return value > 0 means to resubmit the input, but 1251 * it wants the return to be -protocol, or 0 1252 */ 1253 if (ret > 0) 1254 return -ret; 1255 return 0; 1256 } 1257 1258 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) 1259 goto drop; 1260 nf_reset(skb); 1261 1262 /* No socket. Drop packet silently, if checksum is wrong */ 1263 if (udp_lib_checksum_complete(skb)) 1264 goto csum_error; 1265 1266 UDP_INC_STATS_BH(UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE); 1267 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); 1268 1269 /* 1270 * Hmm. We got an UDP packet to a port to which we 1271 * don't wanna listen. Ignore it. 1272 */ 1273 kfree_skb(skb); 1274 return 0; 1275 1276short_packet: 1277 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %u.%u.%u.%u:%u %d/%d to %u.%u.%u.%u:%u\n", 1278 proto == IPPROTO_UDPLITE ? "-Lite" : "", 1279 NIPQUAD(saddr), 1280 ntohs(uh->source), 1281 ulen, 1282 skb->len, 1283 NIPQUAD(daddr), 1284 ntohs(uh->dest)); 1285 goto drop; 1286 1287csum_error: 1288 /* 1289 * RFC1122: OK. Discards the bad packet silently (as far as 1290 * the network is concerned, anyway) as per 4.1.3.4 (MUST). 1291 */ 1292 LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %d.%d.%d.%d:%d to %d.%d.%d.%d:%d ulen %d\n", 1293 proto == IPPROTO_UDPLITE ? "-Lite" : "", 1294 NIPQUAD(saddr), 1295 ntohs(uh->source), 1296 NIPQUAD(daddr), 1297 ntohs(uh->dest), 1298 ulen); 1299drop: 1300 UDP_INC_STATS_BH(UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE); 1301 kfree_skb(skb); 1302 return 0; 1303} 1304 1305int udp_rcv(struct sk_buff *skb) 1306{ 1307 return __udp4_lib_rcv(skb, udp_hash, IPPROTO_UDP); 1308} 1309 1310int udp_destroy_sock(struct sock *sk) 1311{ 1312 lock_sock(sk); 1313 udp_flush_pending_frames(sk); 1314 release_sock(sk); 1315 return 0; 1316} 1317 1318/* 1319 * Socket option code for UDP 1320 */ 1321int udp_lib_setsockopt(struct sock *sk, int level, int optname, 1322 char __user *optval, int optlen, 1323 int (*push_pending_frames)(struct sock *)) 1324{ 1325 struct udp_sock *up = udp_sk(sk); 1326 int val; 1327 int err = 0; 1328 1329 if (optlen<sizeof(int)) 1330 return -EINVAL; 1331 1332 if (get_user(val, (int __user *)optval)) 1333 return -EFAULT; 1334 1335 switch (optname) { 1336 case UDP_CORK: 1337 if (val != 0) { 1338 up->corkflag = 1; 1339 } else { 1340 up->corkflag = 0; 1341 lock_sock(sk); 1342 (*push_pending_frames)(sk); 1343 release_sock(sk); 1344 } 1345 break; 1346 1347 case UDP_ENCAP: 1348 switch (val) { 1349 case 0: 1350 case UDP_ENCAP_ESPINUDP: 1351 case UDP_ENCAP_ESPINUDP_NON_IKE: 1352 up->encap_type = val; 1353 break; 1354 default: 1355 err = -ENOPROTOOPT; 1356 break; 1357 } 1358 break; 1359 1360 /* 1361 * UDP-Lite's partial checksum coverage (RFC 3828). 1362 */ 1363 /* The sender sets actual checksum coverage length via this option. 1364 * The case coverage > packet length is handled by send module. */ 1365 case UDPLITE_SEND_CSCOV: 1366 if (!up->pcflag) /* Disable the option on UDP sockets */ 1367 return -ENOPROTOOPT; 1368 if (val != 0 && val < 8) /* Illegal coverage: use default (8) */ 1369 val = 8; 1370 up->pcslen = val; 1371 up->pcflag |= UDPLITE_SEND_CC; 1372 break; 1373 1374 /* The receiver specifies a minimum checksum coverage value. To make 1375 * sense, this should be set to at least 8 (as done below). If zero is 1376 * used, this again means full checksum coverage. */ 1377 case UDPLITE_RECV_CSCOV: 1378 if (!up->pcflag) /* Disable the option on UDP sockets */ 1379 return -ENOPROTOOPT; 1380 if (val != 0 && val < 8) /* Avoid silly minimal values. */ 1381 val = 8; 1382 up->pcrlen = val; 1383 up->pcflag |= UDPLITE_RECV_CC; 1384 break; 1385 1386 default: 1387 err = -ENOPROTOOPT; 1388 break; 1389 } 1390 1391 return err; 1392} 1393 1394int udp_setsockopt(struct sock *sk, int level, int optname, 1395 char __user *optval, int optlen) 1396{ 1397 if (level == SOL_UDP || level == SOL_UDPLITE) 1398 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1399 udp_push_pending_frames); 1400 return ip_setsockopt(sk, level, optname, optval, optlen); 1401} 1402 1403#ifdef CONFIG_COMPAT 1404int compat_udp_setsockopt(struct sock *sk, int level, int optname, 1405 char __user *optval, int optlen) 1406{ 1407 if (level == SOL_UDP || level == SOL_UDPLITE) 1408 return udp_lib_setsockopt(sk, level, optname, optval, optlen, 1409 udp_push_pending_frames); 1410 return compat_ip_setsockopt(sk, level, optname, optval, optlen); 1411} 1412#endif 1413 1414int udp_lib_getsockopt(struct sock *sk, int level, int optname, 1415 char __user *optval, int __user *optlen) 1416{ 1417 struct udp_sock *up = udp_sk(sk); 1418 int val, len; 1419 1420 if (get_user(len,optlen)) 1421 return -EFAULT; 1422 1423 len = min_t(unsigned int, len, sizeof(int)); 1424 1425 if (len < 0) 1426 return -EINVAL; 1427 1428 switch (optname) { 1429 case UDP_CORK: 1430 val = up->corkflag; 1431 break; 1432 1433 case UDP_ENCAP: 1434 val = up->encap_type; 1435 break; 1436 1437 /* The following two cannot be changed on UDP sockets, the return is 1438 * always 0 (which corresponds to the full checksum coverage of UDP). */ 1439 case UDPLITE_SEND_CSCOV: 1440 val = up->pcslen; 1441 break; 1442 1443 case UDPLITE_RECV_CSCOV: 1444 val = up->pcrlen; 1445 break; 1446 1447 default: 1448 return -ENOPROTOOPT; 1449 } 1450 1451 if (put_user(len, optlen)) 1452 return -EFAULT; 1453 if (copy_to_user(optval, &val,len)) 1454 return -EFAULT; 1455 return 0; 1456} 1457 1458int udp_getsockopt(struct sock *sk, int level, int optname, 1459 char __user *optval, int __user *optlen) 1460{ 1461 if (level == SOL_UDP || level == SOL_UDPLITE) 1462 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1463 return ip_getsockopt(sk, level, optname, optval, optlen); 1464} 1465 1466#ifdef CONFIG_COMPAT 1467int compat_udp_getsockopt(struct sock *sk, int level, int optname, 1468 char __user *optval, int __user *optlen) 1469{ 1470 if (level == SOL_UDP || level == SOL_UDPLITE) 1471 return udp_lib_getsockopt(sk, level, optname, optval, optlen); 1472 return compat_ip_getsockopt(sk, level, optname, optval, optlen); 1473} 1474#endif 1475unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait) 1476{ 1477 unsigned int mask = datagram_poll(file, sock, wait); 1478 struct sock *sk = sock->sk; 1479 int is_lite = IS_UDPLITE(sk); 1480 1481 /* Check for false positives due to checksum errors */ 1482 if ( (mask & POLLRDNORM) && 1483 !(file->f_flags & O_NONBLOCK) && 1484 !(sk->sk_shutdown & RCV_SHUTDOWN)){ 1485 struct sk_buff_head *rcvq = &sk->sk_receive_queue; 1486 struct sk_buff *skb; 1487 1488 spin_lock_bh(&rcvq->lock); 1489 while ((skb = skb_peek(rcvq)) != NULL && 1490 udp_lib_checksum_complete(skb)) { 1491 UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_lite); 1492 __skb_unlink(skb, rcvq); 1493 kfree_skb(skb); 1494 } 1495 spin_unlock_bh(&rcvq->lock); 1496 1497 /* nothing to see, move along */ 1498 if (skb == NULL) 1499 mask &= ~(POLLIN | POLLRDNORM); 1500 } 1501 1502 return mask; 1503 1504} 1505 1506struct proto udp_prot = { 1507 .name = "UDP", 1508 .owner = THIS_MODULE, 1509 .close = udp_lib_close, 1510 .connect = ip4_datagram_connect, 1511 .disconnect = udp_disconnect, 1512 .ioctl = udp_ioctl, 1513 .destroy = udp_destroy_sock, 1514 .setsockopt = udp_setsockopt, 1515 .getsockopt = udp_getsockopt, 1516 .sendmsg = udp_sendmsg, 1517 .recvmsg = udp_recvmsg, 1518 .sendpage = udp_sendpage, 1519 .backlog_rcv = udp_queue_rcv_skb, 1520 .hash = udp_lib_hash, 1521 .unhash = udp_lib_unhash, 1522 .get_port = udp_v4_get_port, 1523 .obj_size = sizeof(struct udp_sock), 1524#ifdef CONFIG_COMPAT 1525 .compat_setsockopt = compat_udp_setsockopt, 1526 .compat_getsockopt = compat_udp_getsockopt, 1527#endif 1528}; 1529 1530/* ------------------------------------------------------------------------ */ 1531#ifdef CONFIG_PROC_FS 1532 1533static struct sock *udp_get_first(struct seq_file *seq) 1534{ 1535 struct sock *sk; 1536 struct udp_iter_state *state = seq->private; 1537 1538 for (state->bucket = 0; state->bucket < UDP_HTABLE_SIZE; ++state->bucket) { 1539 struct hlist_node *node; 1540 sk_for_each(sk, node, state->hashtable + state->bucket) { 1541 if (sk->sk_family == state->family) 1542 goto found; 1543 } 1544 } 1545 sk = NULL; 1546found: 1547 return sk; 1548} 1549 1550static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk) 1551{ 1552 struct udp_iter_state *state = seq->private; 1553 1554 do { 1555 sk = sk_next(sk); 1556try_again: 1557 ; 1558 } while (sk && sk->sk_family != state->family); 1559 1560 if (!sk && ++state->bucket < UDP_HTABLE_SIZE) { 1561 sk = sk_head(state->hashtable + state->bucket); 1562 goto try_again; 1563 } 1564 return sk; 1565} 1566 1567static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos) 1568{ 1569 struct sock *sk = udp_get_first(seq); 1570 1571 if (sk) 1572 while (pos && (sk = udp_get_next(seq, sk)) != NULL) 1573 --pos; 1574 return pos ? NULL : sk; 1575} 1576 1577static void *udp_seq_start(struct seq_file *seq, loff_t *pos) 1578{ 1579 read_lock(&udp_hash_lock); 1580 return *pos ? udp_get_idx(seq, *pos-1) : (void *)1; 1581} 1582 1583static void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1584{ 1585 struct sock *sk; 1586 1587 if (v == (void *)1) 1588 sk = udp_get_idx(seq, 0); 1589 else 1590 sk = udp_get_next(seq, v); 1591 1592 ++*pos; 1593 return sk; 1594} 1595 1596static void udp_seq_stop(struct seq_file *seq, void *v) 1597{ 1598 read_unlock(&udp_hash_lock); 1599} 1600 1601static int udp_seq_open(struct inode *inode, struct file *file) 1602{ 1603 struct udp_seq_afinfo *afinfo = PDE(inode)->data; 1604 struct seq_file *seq; 1605 int rc = -ENOMEM; 1606 struct udp_iter_state *s = kzalloc(sizeof(*s), GFP_KERNEL); 1607 1608 if (!s) 1609 goto out; 1610 s->family = afinfo->family; 1611 s->hashtable = afinfo->hashtable; 1612 s->seq_ops.start = udp_seq_start; 1613 s->seq_ops.next = udp_seq_next; 1614 s->seq_ops.show = afinfo->seq_show; 1615 s->seq_ops.stop = udp_seq_stop; 1616 1617 rc = seq_open(file, &s->seq_ops); 1618 if (rc) 1619 goto out_kfree; 1620 1621 seq = file->private_data; 1622 seq->private = s; 1623out: 1624 return rc; 1625out_kfree: 1626 kfree(s); 1627 goto out; 1628} 1629 1630/* ------------------------------------------------------------------------ */ 1631int udp_proc_register(struct udp_seq_afinfo *afinfo) 1632{ 1633 struct proc_dir_entry *p; 1634 int rc = 0; 1635 1636 if (!afinfo) 1637 return -EINVAL; 1638 afinfo->seq_fops->owner = afinfo->owner; 1639 afinfo->seq_fops->open = udp_seq_open; 1640 afinfo->seq_fops->read = seq_read; 1641 afinfo->seq_fops->llseek = seq_lseek; 1642 afinfo->seq_fops->release = seq_release_private; 1643 1644 p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops); 1645 if (p) 1646 p->data = afinfo; 1647 else 1648 rc = -ENOMEM; 1649 return rc; 1650} 1651 1652void udp_proc_unregister(struct udp_seq_afinfo *afinfo) 1653{ 1654 if (!afinfo) 1655 return; 1656 proc_net_remove(afinfo->name); 1657 memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops)); 1658} 1659 1660/* ------------------------------------------------------------------------ */ 1661static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket) 1662{ 1663 struct inet_sock *inet = inet_sk(sp); 1664 __be32 dest = inet->daddr; 1665 __be32 src = inet->rcv_saddr; 1666 __u16 destp = ntohs(inet->dport); 1667 __u16 srcp = ntohs(inet->sport); 1668 1669 sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" 1670 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p", 1671 bucket, src, srcp, dest, destp, sp->sk_state, 1672 atomic_read(&sp->sk_wmem_alloc), 1673 atomic_read(&sp->sk_rmem_alloc), 1674 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), 1675 atomic_read(&sp->sk_refcnt), sp); 1676} 1677 1678int udp4_seq_show(struct seq_file *seq, void *v) 1679{ 1680 if (v == SEQ_START_TOKEN) 1681 seq_printf(seq, "%-127s\n", 1682 " sl local_address rem_address st tx_queue " 1683 "rx_queue tr tm->when retrnsmt uid timeout " 1684 "inode"); 1685 else { 1686 char tmpbuf[129]; 1687 struct udp_iter_state *state = seq->private; 1688 1689 udp4_format_sock(v, tmpbuf, state->bucket); 1690 seq_printf(seq, "%-127s\n", tmpbuf); 1691 } 1692 return 0; 1693} 1694 1695/* ------------------------------------------------------------------------ */ 1696static struct file_operations udp4_seq_fops; 1697static struct udp_seq_afinfo udp4_seq_afinfo = { 1698 .owner = THIS_MODULE, 1699 .name = "udp", 1700 .family = AF_INET, 1701 .hashtable = udp_hash, 1702 .seq_show = udp4_seq_show, 1703 .seq_fops = &udp4_seq_fops, 1704}; 1705 1706int __init udp4_proc_init(void) 1707{ 1708 return udp_proc_register(&udp4_seq_afinfo); 1709} 1710 1711void udp4_proc_exit(void) 1712{ 1713 udp_proc_unregister(&udp4_seq_afinfo); 1714} 1715#endif /* CONFIG_PROC_FS */ 1716 1717EXPORT_SYMBOL(udp_disconnect); 1718EXPORT_SYMBOL(udp_hash); 1719EXPORT_SYMBOL(udp_hash_lock); 1720EXPORT_SYMBOL(udp_ioctl); 1721EXPORT_SYMBOL(udp_get_port); 1722EXPORT_SYMBOL(udp_prot); 1723EXPORT_SYMBOL(udp_sendmsg); 1724EXPORT_SYMBOL(udp_lib_getsockopt); 1725EXPORT_SYMBOL(udp_lib_setsockopt); 1726EXPORT_SYMBOL(udp_poll); 1727 1728#ifdef CONFIG_PROC_FS 1729EXPORT_SYMBOL(udp_proc_register); 1730EXPORT_SYMBOL(udp_proc_unregister); 1731#endif 1732