1/*********************************************************************** 2* 3* pppoe.h 4* 5* Declaration of various PPPoE constants 6* 7* Copyright (C) 2000-2012 Roaring Penguin Software Inc. 8* 9* This program may be distributed according to the terms of the GNU 10* General Public License, version 2 or (at your option) any later version. 11* 12* LIC: GPL 13* 14* $Id$ 15* 16***********************************************************************/ 17 18#include "config.h" 19 20extern int IsSetID; 21 22#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H) 23#define _POSIX_SOURCE 1 /* For sigaction defines */ 24#endif 25 26#include <stdio.h> /* For FILE */ 27#include <sys/types.h> /* For pid_t */ 28 29/* How do we access raw Ethernet devices? */ 30#undef USE_LINUX_PACKET 31#undef USE_BPF 32 33#if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H) 34#define USE_LINUX_PACKET 1 35#elif defined(HAVE_SYS_DLPI_H) 36#define USE_DLPI 37#elif defined(HAVE_NET_BPF_H) 38#define USE_BPF 1 39#endif 40 41/* Sanity check */ 42#if !defined(USE_BPF) && !defined(USE_LINUX_PACKET) && !defined(USE_DLPI) 43#error Unknown method for accessing raw Ethernet frames 44#endif 45 46#ifdef HAVE_SYS_CDEFS_H 47#include <sys/cdefs.h> 48#endif 49 50#ifdef HAVE_SYS_SOCKET_H 51#include <sys/socket.h> 52#endif 53 54/* Ugly header files on some Linux boxes... */ 55#if defined(HAVE_LINUX_IF_H) 56#include <linux/if.h> 57#elif defined(HAVE_NET_IF_H) 58#include <net/if.h> 59#endif 60 61#ifdef HAVE_NET_IF_TYPES_H 62#include <net/if_types.h> 63#endif 64 65#ifdef HAVE_NET_IF_DL_H 66#include <net/if_dl.h> 67#endif 68 69/* I'm not sure why this is needed... I do not have OpenBSD */ 70#if defined(__OpenBSD__) 71#include <net/ppp_defs.h> 72#include <net/if_ppp.h> 73#endif 74 75#ifdef USE_BPF 76extern int bpfSize; 77struct PPPoEPacketStruct; 78void sessionDiscoveryPacket(struct PPPoEPacketStruct *packet); 79#define BPF_BUFFER_IS_EMPTY (bpfSize <= 0) 80#define BPF_BUFFER_HAS_DATA (bpfSize > 0) 81#define ethhdr ether_header 82#define h_dest ether_dhost 83#define h_source ether_shost 84#define h_proto ether_type 85#define ETH_DATA_LEN ETHERMTU 86#define ETH_ALEN ETHER_ADDR_LEN 87#else 88#undef USE_BPF 89#define BPF_BUFFER_IS_EMPTY 1 90#define BPF_BUFFER_HAS_DATA 0 91#endif 92 93#ifdef USE_DLPI 94#include <sys/ethernet.h> 95#define ethhdr ether_header 96#define ETH_DATA_LEN ETHERMTU 97#define ETH_ALEN ETHERADDRL 98#define h_dest ether_dhost.ether_addr_octet 99#define h_source ether_shost.ether_addr_octet 100#define h_proto ether_type 101 102/* cloned from dltest.h */ 103#define MAXDLBUF 8192 104#define MAXDLADDR 1024 105#define MAXWAIT 15 106#define OFFADDR(s, n) (u_char*)((char*)(s) + (int)(n)) 107#define CASERET(s) case s: return ("s") 108 109#endif 110 111/* Define various integer types -- assumes a char is 8 bits */ 112#if SIZEOF_UNSIGNED_SHORT == 2 113typedef unsigned short UINT16_t; 114#elif SIZEOF_UNSIGNED_INT == 2 115typedef unsigned int UINT16_t; 116#else 117#error Could not find a 16-bit integer type 118#endif 119 120#if SIZEOF_UNSIGNED_SHORT == 4 121typedef unsigned short UINT32_t; 122#elif SIZEOF_UNSIGNED_INT == 4 123typedef unsigned int UINT32_t; 124#elif SIZEOF_UNSIGNED_LONG == 4 125typedef unsigned long UINT32_t; 126#else 127#error Could not find a 32-bit integer type 128#endif 129 130#ifdef HAVE_LINUX_IF_ETHER_H 131#include <linux/if_ether.h> 132#endif 133 134#include <netinet/in.h> 135 136#ifdef HAVE_NETINET_IF_ETHER_H 137#include <sys/types.h> 138 139#ifdef HAVE_SYS_SOCKET_H 140#include <sys/socket.h> 141#endif 142#ifndef HAVE_SYS_DLPI_H 143#include <netinet/if_ether.h> 144#endif 145#endif 146 147 148 149/* Ethernet frame types according to RFC 2516 */ 150#define ETH_PPPOE_DISCOVERY 0x8863 151#define ETH_PPPOE_SESSION 0x8864 152 153/* But some brain-dead peers disobey the RFC, so frame types are variables */ 154extern UINT16_t Eth_PPPOE_Discovery; 155extern UINT16_t Eth_PPPOE_Session; 156 157extern void switchToRealID(void); 158extern void switchToEffectiveID(void); 159extern void dropPrivs(void); 160 161/* PPPoE codes */ 162#define CODE_PADI 0x09 163#define CODE_PADO 0x07 164#define CODE_PADR 0x19 165#define CODE_PADS 0x65 166#define CODE_PADT 0xA7 167 168/* Extensions from draft-carrel-info-pppoe-ext-00 */ 169/* I do NOT like PADM or PADN, but they are here for completeness */ 170#define CODE_PADM 0xD3 171#define CODE_PADN 0xD4 172 173#define CODE_SESS 0x00 174 175/* PPPoE Tags */ 176#define TAG_END_OF_LIST 0x0000 177#define TAG_SERVICE_NAME 0x0101 178#define TAG_AC_NAME 0x0102 179#define TAG_HOST_UNIQ 0x0103 180#define TAG_AC_COOKIE 0x0104 181#define TAG_VENDOR_SPECIFIC 0x0105 182#define TAG_RELAY_SESSION_ID 0x0110 183#define TAG_PPP_MAX_PAYLOAD 0x0120 184#define TAG_SERVICE_NAME_ERROR 0x0201 185#define TAG_AC_SYSTEM_ERROR 0x0202 186#define TAG_GENERIC_ERROR 0x0203 187 188/* Extensions from draft-carrel-info-pppoe-ext-00 */ 189/* I do NOT like these tags one little bit */ 190#define TAG_HURL 0x111 191#define TAG_MOTM 0x112 192#define TAG_IP_ROUTE_ADD 0x121 193 194/* Discovery phase states */ 195#define STATE_SENT_PADI 0 196#define STATE_RECEIVED_PADO 1 197#define STATE_SENT_PADR 2 198#define STATE_SESSION 3 199#define STATE_TERMINATED 4 200 201/* How many PADI/PADS attempts? */ 202#define MAX_PADI_ATTEMPTS 3 203 204/* Initial timeout for PADO/PADS */ 205#define PADI_TIMEOUT 5 206 207/* States for scanning PPP frames */ 208#define STATE_WAITFOR_FRAME_ADDR 0 209#define STATE_DROP_PROTO 1 210#define STATE_BUILDING_PACKET 2 211 212/* Special PPP frame characters */ 213#define FRAME_ESC 0x7D 214#define FRAME_FLAG 0x7E 215#define FRAME_ADDR 0xFF 216#define FRAME_CTRL 0x03 217#define FRAME_ENC 0x20 218 219#define IPV4ALEN 4 220#define SMALLBUF 256 221 222/* Allow for 1500-byte PPPoE data which makes the 223 Ethernet packet size bigger by 8 bytes */ 224#define ETH_JUMBO_LEN (ETH_DATA_LEN+8) 225 226/* A PPPoE Packet, including Ethernet headers */ 227typedef struct PPPoEPacketStruct { 228 struct ethhdr ethHdr; /* Ethernet header */ 229#ifdef PACK_BITFIELDS_REVERSED 230 unsigned int type:4; /* PPPoE Type (must be 1) */ 231 unsigned int ver:4; /* PPPoE Version (must be 1) */ 232#else 233 unsigned int ver:4; /* PPPoE Version (must be 1) */ 234 unsigned int type:4; /* PPPoE Type (must be 1) */ 235#endif 236 unsigned int code:8; /* PPPoE code */ 237 unsigned int session:16; /* PPPoE session */ 238 unsigned int length:16; /* Payload length */ 239 unsigned char payload[ETH_JUMBO_LEN]; /* A bit of room to spare */ 240} PPPoEPacket; 241 242/* Header size of a PPPoE packet */ 243#define PPPOE_OVERHEAD 6 /* type, code, session, length */ 244#define HDR_SIZE (sizeof(struct ethhdr) + PPPOE_OVERHEAD) 245#define MAX_PPPOE_PAYLOAD (ETH_JUMBO_LEN - PPPOE_OVERHEAD) 246#define PPP_OVERHEAD 2 247#define MAX_PPPOE_MTU (MAX_PPPOE_PAYLOAD - PPP_OVERHEAD) 248#define TOTAL_OVERHEAD (PPPOE_OVERHEAD + PPP_OVERHEAD) 249 250/* Normal PPPoE MTU without jumbo frames */ 251#define ETH_PPPOE_MTU (ETH_DATA_LEN - TOTAL_OVERHEAD) 252 253/* PPPoE Tag */ 254 255typedef struct PPPoETagStruct { 256 unsigned int type:16; /* tag type */ 257 unsigned int length:16; /* Length of payload */ 258 unsigned char payload[ETH_JUMBO_LEN]; /* A LOT of room to spare */ 259} PPPoETag; 260/* Header size of a PPPoE tag */ 261#define TAG_HDR_SIZE 4 262 263/* Chunk to read from stdin */ 264#define READ_CHUNK 4096 265 266/* Function passed to parsePacket */ 267typedef void ParseFunc(UINT16_t type, 268 UINT16_t len, 269 unsigned char *data, 270 void *extra); 271 272#define PPPINITFCS16 0xffff /* Initial FCS value */ 273 274/* Keep track of the state of a connection -- collect everything in 275 one spot */ 276 277typedef struct PPPoEConnectionStruct { 278 int discoveryState; /* Where we are in discovery */ 279 int discoverySocket; /* Raw socket for discovery frames */ 280 int sessionSocket; /* Raw socket for session frames */ 281 unsigned char myEth[ETH_ALEN]; /* My MAC address */ 282 unsigned char peerEth[ETH_ALEN]; /* Peer's MAC address */ 283#ifdef PLUGIN 284 unsigned char req_peer_mac[ETH_ALEN]; /* required peer MAC address */ 285 unsigned char req_peer; /* require mac addr to match req_peer_mac */ 286#endif 287 288 UINT16_t session; /* Session ID */ 289 char *ifName; /* Interface name */ 290 char *serviceName; /* Desired service name, if any */ 291 char *acName; /* Desired AC name, if any */ 292 int synchronous; /* Use synchronous PPP */ 293 int useHostUniq; /* Use Host-Uniq tag */ 294 int printACNames; /* Just print AC names */ 295 int skipDiscovery; /* Skip discovery */ 296 int noDiscoverySocket; /* Don't even open discovery socket */ 297 int killSession; /* Kill session and exit */ 298 FILE *debugFile; /* Debug file for dumping packets */ 299 int numPADOs; /* Number of PADO packets received */ 300 PPPoETag cookie; /* We have to send this if we get it */ 301 PPPoETag relayId; /* Ditto */ 302 int PADSHadError; /* If PADS had an error tag */ 303 int discoveryTimeout; /* Timeout for discovery packets */ 304#ifdef PLUGIN 305 int seenMaxPayload; 306 int mtu; 307 int mru; 308#endif 309} PPPoEConnection; 310 311/* Structure used to determine acceptable PADO or PADS packet */ 312struct PacketCriteria { 313 PPPoEConnection *conn; 314 int acNameOK; 315 int serviceNameOK; 316 int seenACName; 317 int seenServiceName; 318 int gotError; 319}; 320 321/* Function Prototypes */ 322UINT16_t etherType(PPPoEPacket *packet); 323int openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr, UINT16_t *mtu); 324int sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size); 325int receivePacket(int sock, PPPoEPacket *pkt, int *size); 326void fatalSys(char const *str); 327void rp_fatal(char const *str); 328void printErr(char const *str); 329void sysErr(char const *str); 330#ifdef DEBUGGING_ENABLED 331void dumpPacket(FILE *fp, PPPoEPacket *packet, char const *dir); 332void dumpHex(FILE *fp, unsigned char const *buf, int len); 333#endif 334int parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra); 335void parseLogErrs(UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra); 336void pktLogErrs(char const *pkt, UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra); 337void syncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 338void asyncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 339void asyncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 340void syncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 341char *strDup(char const *str); 342void sendPADT(PPPoEConnection *conn, char const *msg); 343void sendPADTf(PPPoEConnection *conn, char const *fmt, ...); 344 345void sendSessionPacket(PPPoEConnection *conn, 346 PPPoEPacket *packet, int len); 347void initPPP(void); 348void clampMSS(PPPoEPacket *packet, char const *dir, int clampMss); 349UINT16_t computeTCPChecksum(unsigned char *ipHdr, unsigned char *tcpHdr); 350UINT16_t pppFCS16(UINT16_t fcs, unsigned char *cp, int len); 351void discovery(PPPoEConnection *conn); 352unsigned char *findTag(PPPoEPacket *packet, UINT16_t tagType, 353 PPPoETag *tag); 354 355#define SET_STRING(var, val) do { if (var) free(var); var = strDup(val); } while(0); 356 357#define CHECK_ROOM(cursor, start, len) \ 358do {\ 359 if (((cursor)-(start))+(len) > MAX_PPPOE_PAYLOAD) { \ 360 syslog(LOG_ERR, "Would create too-long packet"); \ 361 return; \ 362 } \ 363} while(0) 364 365/* True if Ethernet address is broadcast or multicast */ 366#define NOT_UNICAST(e) ((e[0] & 0x01) != 0) 367#define BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) == 0xFF) 368#define NOT_BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) != 0xFF) 369