1 /*********************************************************************** 2 * 3 * pppoe.h 4 * 5 * Declaration of various PPPoE constants 6 * 7 * Copyright (C) 2000 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 * $Id: pppoe.h,v 1.2 2004/11/04 10:07:37 paulus Exp $ 13 * 14 ***********************************************************************/ 15 16 #ifdef __sun__ 17 #define __EXTENSIONS__ 18 #endif 19 20 #include "config.h" 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 76 extern int bpfSize; 77 struct PPPoEPacketStruct; 78 void 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 == 2 113 typedef unsigned short UINT16_t; 114 #elif SIZEOF_UNSIGNED_INT == 2 115 typedef unsigned int UINT16_t; 116 #else 117 #error Could not find a 16-bit integer type 118 #endif 119 120 #if SIZEOF_UNSIGNED_SHORT == 4 121 typedef unsigned short UINT32_t; 122 #elif SIZEOF_UNSIGNED_INT == 4 123 typedef unsigned int UINT32_t; 124 #elif SIZEOF_UNSIGNED_LONG == 4 125 typedef unsigned long UINT32_t; 126 #else 127 #error Could not find a 16-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 */ 154 extern UINT16_t Eth_PPPOE_Discovery; 155 extern UINT16_t Eth_PPPOE_Session; 156 157 /* PPPoE codes */ 158 #define CODE_PADI 0x09 159 #define CODE_PADO 0x07 160 #define CODE_PADR 0x19 161 #define CODE_PADS 0x65 162 #define CODE_PADT 0xA7 163 #define CODE_SESS 0x00 164 165 /* PPPoE Tags */ 166 #define TAG_END_OF_LIST 0x0000 167 #define TAG_SERVICE_NAME 0x0101 168 #define TAG_AC_NAME 0x0102 169 #define TAG_HOST_UNIQ 0x0103 170 #define TAG_AC_COOKIE 0x0104 171 #define TAG_VENDOR_SPECIFIC 0x0105 172 #define TAG_RELAY_SESSION_ID 0x0110 173 #define TAG_SERVICE_NAME_ERROR 0x0201 174 #define TAG_AC_SYSTEM_ERROR 0x0202 175 #define TAG_GENERIC_ERROR 0x0203 176 177 /* Discovery phase states */ 178 #define STATE_SENT_PADI 0 179 #define STATE_RECEIVED_PADO 1 180 #define STATE_SENT_PADR 2 181 #define STATE_SESSION 3 182 #define STATE_TERMINATED 4 183 184 /* How many PADI/PADS attempts? */ 185 #define MAX_PADI_ATTEMPTS 3 186 187 /* Initial timeout for PADO/PADS */ 188 #define PADI_TIMEOUT 5 189 190 /* States for scanning PPP frames */ 191 #define STATE_WAITFOR_FRAME_ADDR 0 192 #define STATE_DROP_PROTO 1 193 #define STATE_BUILDING_PACKET 2 194 195 /* Special PPP frame characters */ 196 #define FRAME_ESC 0x7D 197 #define FRAME_FLAG 0x7E 198 #define FRAME_ADDR 0xFF 199 #define FRAME_CTRL 0x03 200 #define FRAME_ENC 0x20 201 202 #define IPV4ALEN 4 203 #define SMALLBUF 256 204 205 /* A PPPoE Packet, including Ethernet headers */ 206 typedef struct PPPoEPacketStruct { 207 struct ethhdr ethHdr; /* Ethernet header */ 208 #ifdef PACK_BITFIELDS_REVERSED 209 unsigned int type:4; /* PPPoE Type (must be 1) */ 210 unsigned int ver:4; /* PPPoE Version (must be 1) */ 211 #else 212 unsigned int ver:4; /* PPPoE Version (must be 1) */ 213 unsigned int type:4; /* PPPoE Type (must be 1) */ 214 #endif 215 unsigned int code:8; /* PPPoE code */ 216 unsigned int session:16; /* PPPoE session */ 217 unsigned int length:16; /* Payload length */ 218 unsigned char payload[ETH_DATA_LEN]; /* A bit of room to spare */ 219 } PPPoEPacket; 220 221 /* Header size of a PPPoE packet */ 222 #define PPPOE_OVERHEAD 6 /* type, code, session, length */ 223 #define HDR_SIZE (sizeof(struct ethhdr) + PPPOE_OVERHEAD) 224 #define MAX_PPPOE_PAYLOAD (ETH_DATA_LEN - PPPOE_OVERHEAD) 225 #define MAX_PPPOE_MTU (MAX_PPPOE_PAYLOAD - 2) 226 227 /* PPPoE Tag */ 228 229 typedef struct PPPoETagStruct { 230 unsigned int type:16; /* tag type */ 231 unsigned int length:16; /* Length of payload */ 232 unsigned char payload[ETH_DATA_LEN]; /* A LOT of room to spare */ 233 } PPPoETag; 234 /* Header size of a PPPoE tag */ 235 #define TAG_HDR_SIZE 4 236 237 /* Chunk to read from stdin */ 238 #define READ_CHUNK 4096 239 240 /* Function passed to parsePacket */ 241 typedef void ParseFunc(UINT16_t type, 242 UINT16_t len, 243 unsigned char *data, 244 void *extra); 245 246 #define PPPINITFCS16 0xffff /* Initial FCS value */ 247 248 /* Keep track of the state of a connection -- collect everything in 249 one spot */ 250 251 typedef struct PPPoEConnectionStruct { 252 int discoveryState; /* Where we are in discovery */ 253 int discoverySocket; /* Raw socket for discovery frames */ 254 int sessionSocket; /* Raw socket for session frames */ 255 unsigned char myEth[ETH_ALEN]; /* My MAC address */ 256 unsigned char peerEth[ETH_ALEN]; /* Peer's MAC address */ 257 UINT16_t session; /* Session ID */ 258 char *ifName; /* Interface name */ 259 char *serviceName; /* Desired service name, if any */ 260 char *acName; /* Desired AC name, if any */ 261 int synchronous; /* Use synchronous PPP */ 262 int useHostUniq; /* Use Host-Uniq tag */ 263 int printACNames; /* Just print AC names */ 264 int skipDiscovery; /* Skip discovery */ 265 int noDiscoverySocket; /* Don't even open discovery socket */ 266 FILE *debugFile; /* Debug file for dumping packets */ 267 int numPADOs; /* Number of PADO packets received */ 268 PPPoETag cookie; /* We have to send this if we get it */ 269 PPPoETag relayId; /* Ditto */ 270 } PPPoEConnection; 271 272 /* Structure used to determine acceptable PADO or PADS packet */ 273 struct PacketCriteria { 274 PPPoEConnection *conn; 275 int acNameOK; 276 int serviceNameOK; 277 int seenACName; 278 int seenServiceName; 279 }; 280 281 /* Function Prototypes */ 282 UINT16_t etherType(PPPoEPacket *packet); 283 int openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr); 284 int sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size); 285 int receivePacket(int sock, PPPoEPacket *pkt, int *size); 286 void fatalSys(char const *str); 287 void rp_fatal(char const *str); 288 void printErr(char const *str); 289 void sysErr(char const *str); 290 void dumpPacket(FILE *fp, PPPoEPacket *packet, char const *dir); 291 void dumpHex(FILE *fp, unsigned char const *buf, int len); 292 int parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra); 293 void parseLogErrs(UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra); 294 void syncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 295 void asyncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 296 void asyncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 297 void syncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 298 char *strDup(char const *str); 299 void sendPADT(PPPoEConnection *conn, char const *msg); 300 void sendSessionPacket(PPPoEConnection *conn, 301 PPPoEPacket *packet, int len); 302 void initPPP(void); 303 void clampMSS(PPPoEPacket *packet, char const *dir, int clampMss); 304 UINT16_t computeTCPChecksum(unsigned char *ipHdr, unsigned char *tcpHdr); 305 UINT16_t pppFCS16(UINT16_t fcs, unsigned char *cp, int len); 306 void discovery(PPPoEConnection *conn); 307 unsigned char *findTag(PPPoEPacket *packet, UINT16_t tagType, 308 PPPoETag *tag); 309 310 #define SET_STRING(var, val) do { if (var) free(var); var = strDup(val); } while(0); 311 312 #define CHECK_ROOM(cursor, start, len) \ 313 do {\ 314 if (((cursor)-(start))+(len) > MAX_PPPOE_PAYLOAD) { \ 315 syslog(LOG_ERR, "Would create too-long packet"); \ 316 return; \ 317 } \ 318 } while(0) 319 320 /* True if Ethernet address is broadcast or multicast */ 321 #define NOT_UNICAST(e) ((e[0] & 0x01) != 0) 322 #define BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) == 0xFF) 323 #define NOT_BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) != 0xFF) 324
