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 1.4 2008/06/15 04:35:50 paulus Exp $ 13 * 14 ***********************************************************************/ 15 16 #include "config.h" 17 18 #if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H) 19 #define _POSIX_SOURCE 1 /* For sigaction defines */ 20 #endif 21 22 #include <stdio.h> /* For FILE */ 23 #include <sys/types.h> /* For pid_t */ 24 25 /* How do we access raw Ethernet devices? */ 26 #undef USE_LINUX_PACKET 27 #undef USE_BPF 28 29 #if defined(HAVE_NETPACKET_PACKET_H) || defined(HAVE_LINUX_IF_PACKET_H) 30 #define USE_LINUX_PACKET 1 31 #elif defined(HAVE_SYS_DLPI_H) 32 #define USE_DLPI 33 #elif defined(HAVE_NET_BPF_H) 34 #define USE_BPF 1 35 #endif 36 37 /* Sanity check */ 38 #if !defined(USE_BPF) && !defined(USE_LINUX_PACKET) && !defined(USE_DLPI) 39 #error Unknown method for accessing raw Ethernet frames 40 #endif 41 42 #ifdef HAVE_SYS_CDEFS_H 43 #include <sys/cdefs.h> 44 #endif 45 46 #ifdef HAVE_SYS_SOCKET_H 47 #include <sys/socket.h> 48 #endif 49 50 /* Ugly header files on some Linux boxes... */ 51 #if defined(HAVE_LINUX_IF_H) 52 #include <linux/if.h> 53 #elif defined(HAVE_NET_IF_H) 54 #include <net/if.h> 55 #endif 56 57 #ifdef HAVE_NET_IF_TYPES_H 58 #include <net/if_types.h> 59 #endif 60 61 #define BPF_BUFFER_IS_EMPTY 1 62 #define BPF_BUFFER_HAS_DATA 0 63 64 /* Define various integer types -- assumes a char is 8 bits */ 65 #if SIZEOF_UNSIGNED_SHORT == 2 66 typedef unsigned short UINT16_t; 67 #elif SIZEOF_UNSIGNED_INT == 2 68 typedef unsigned int UINT16_t; 69 #else 70 #error Could not find a 16-bit integer type 71 #endif 72 73 #if SIZEOF_UNSIGNED_SHORT == 4 74 typedef unsigned short UINT32_t; 75 #elif SIZEOF_UNSIGNED_INT == 4 76 typedef unsigned int UINT32_t; 77 #elif SIZEOF_UNSIGNED_LONG == 4 78 typedef unsigned long UINT32_t; 79 #else 80 #error Could not find a 32-bit integer type 81 #endif 82 83 #ifdef HAVE_LINUX_IF_ETHER_H 84 #include <linux/if_ether.h> 85 #endif 86 87 #include <netinet/in.h> 88 89 #ifdef HAVE_NETINET_IF_ETHER_H 90 #include <sys/types.h> 91 92 #ifdef HAVE_SYS_SOCKET_H 93 #include <sys/socket.h> 94 #endif 95 #ifndef HAVE_SYS_DLPI_H 96 #include <netinet/if_ether.h> 97 #endif 98 #endif 99 100 101 102 /* Ethernet frame types according to RFC 2516 */ 103 #define ETH_PPPOE_DISCOVERY 0x8863 104 #define ETH_PPPOE_SESSION 0x8864 105 106 /* But some brain-dead peers disobey the RFC, so frame types are variables */ 107 extern UINT16_t Eth_PPPOE_Discovery; 108 extern UINT16_t Eth_PPPOE_Session; 109 110 /* PPPoE codes */ 111 #define CODE_PADI 0x09 112 #define CODE_PADO 0x07 113 #define CODE_PADR 0x19 114 #define CODE_PADS 0x65 115 #define CODE_PADT 0xA7 116 117 /* Extensions from draft-carrel-info-pppoe-ext-00 */ 118 /* I do NOT like PADM or PADN, but they are here for completeness */ 119 #define CODE_PADM 0xD3 120 #define CODE_PADN 0xD4 121 122 #define CODE_SESS 0x00 123 124 /* PPPoE Tags */ 125 #define TAG_END_OF_LIST 0x0000 126 #define TAG_SERVICE_NAME 0x0101 127 #define TAG_AC_NAME 0x0102 128 #define TAG_HOST_UNIQ 0x0103 129 #define TAG_AC_COOKIE 0x0104 130 #define TAG_VENDOR_SPECIFIC 0x0105 131 #define TAG_RELAY_SESSION_ID 0x0110 132 #define TAG_PPP_MAX_PAYLOAD 0x0120 133 #define TAG_SERVICE_NAME_ERROR 0x0201 134 #define TAG_AC_SYSTEM_ERROR 0x0202 135 #define TAG_GENERIC_ERROR 0x0203 136 137 /* Extensions from draft-carrel-info-pppoe-ext-00 */ 138 /* I do NOT like these tags one little bit */ 139 #define TAG_HURL 0x111 140 #define TAG_MOTM 0x112 141 #define TAG_IP_ROUTE_ADD 0x121 142 143 /* Discovery phase states */ 144 #define STATE_SENT_PADI 0 145 #define STATE_RECEIVED_PADO 1 146 #define STATE_SENT_PADR 2 147 #define STATE_SESSION 3 148 #define STATE_TERMINATED 4 149 150 /* How many PADI/PADS attempts? */ 151 #define MAX_PADI_ATTEMPTS 3 152 153 /* Initial timeout for PADO/PADS */ 154 #define PADI_TIMEOUT 5 155 156 /* States for scanning PPP frames */ 157 #define STATE_WAITFOR_FRAME_ADDR 0 158 #define STATE_DROP_PROTO 1 159 #define STATE_BUILDING_PACKET 2 160 161 /* Special PPP frame characters */ 162 #define FRAME_ESC 0x7D 163 #define FRAME_FLAG 0x7E 164 #define FRAME_ADDR 0xFF 165 #define FRAME_CTRL 0x03 166 #define FRAME_ENC 0x20 167 168 #define IPV4ALEN 4 169 #define SMALLBUF 256 170 171 /* There are other fixed-size buffers preventing 172 this from being increased to 16110. The buffer 173 sizes would need to be properly de-coupled from 174 the default MRU. For now, getting up to 1500 is 175 enough. */ 176 #define ETH_JUMBO_LEN 1508 177 178 /* A PPPoE Packet, including Ethernet headers */ 179 typedef struct PPPoEPacketStruct { 180 struct ethhdr ethHdr; /* Ethernet header */ 181 unsigned int vertype:8; /* PPPoE Version and Type (must both be 1) */ 182 unsigned int code:8; /* PPPoE code */ 183 unsigned int session:16; /* PPPoE session */ 184 unsigned int length:16; /* Payload length */ 185 unsigned char payload[ETH_JUMBO_LEN]; /* A bit of room to spare */ 186 } PPPoEPacket; 187 188 #define PPPOE_VER(vt) ((vt) >> 4) 189 #define PPPOE_TYPE(vt) ((vt) & 0xf) 190 #define PPPOE_VER_TYPE(v, t) (((v) << 4) | (t)) 191 192 /* Header size of a PPPoE packet */ 193 #define PPPOE_OVERHEAD 6 /* type, code, session, length */ 194 #define HDR_SIZE (sizeof(struct ethhdr) + PPPOE_OVERHEAD) 195 #define MAX_PPPOE_PAYLOAD (ETH_JUMBO_LEN - PPPOE_OVERHEAD) 196 #define PPP_OVERHEAD 2 /* protocol */ 197 #define MAX_PPPOE_MTU (MAX_PPPOE_PAYLOAD - PPP_OVERHEAD) 198 #define TOTAL_OVERHEAD (PPPOE_OVERHEAD + PPP_OVERHEAD) 199 #define ETH_PPPOE_MTU (ETH_DATA_LEN - TOTAL_OVERHEAD) 200 201 /* PPPoE Tag */ 202 203 typedef struct PPPoETagStruct { 204 unsigned int type:16; /* tag type */ 205 unsigned int length:16; /* Length of payload */ 206 unsigned char payload[ETH_JUMBO_LEN]; /* A LOT of room to spare */ 207 } PPPoETag; 208 /* Header size of a PPPoE tag */ 209 #define TAG_HDR_SIZE 4 210 211 /* Chunk to read from stdin */ 212 #define READ_CHUNK 4096 213 214 /* Function passed to parsePacket */ 215 typedef void ParseFunc(UINT16_t type, 216 UINT16_t len, 217 unsigned char *data, 218 void *extra); 219 220 #define PPPINITFCS16 0xffff /* Initial FCS value */ 221 222 /* Keep track of the state of a connection -- collect everything in 223 one spot */ 224 225 typedef struct PPPoEConnectionStruct { 226 int discoveryState; /* Where we are in discovery */ 227 int discoverySocket; /* Raw socket for discovery frames */ 228 int sessionSocket; /* Raw socket for session frames */ 229 unsigned char myEth[ETH_ALEN]; /* My MAC address */ 230 unsigned char peerEth[ETH_ALEN]; /* Peer's MAC address */ 231 unsigned char req_peer_mac[ETH_ALEN]; /* required peer MAC address */ 232 unsigned char req_peer; /* require mac addr to match req_peer_mac */ 233 UINT16_t session; /* Session ID */ 234 char *ifName; /* Interface name */ 235 char *serviceName; /* Desired service name, if any */ 236 char *acName; /* Desired AC name, if any */ 237 int synchronous; /* Use synchronous PPP */ 238 int useHostUniq; /* Use Host-Uniq tag */ 239 int printACNames; /* Just print AC names */ 240 FILE *debugFile; /* Debug file for dumping packets */ 241 int numPADOs; /* Number of PADO packets received */ 242 PPPoETag cookie; /* We have to send this if we get it */ 243 PPPoETag relayId; /* Ditto */ 244 int error; /* Error packet received */ 245 int debug; /* Set to log packets sent and received */ 246 int discoveryTimeout; /* Timeout for discovery packets */ 247 int seenMaxPayload; 248 int mtu; /* Stored MTU */ 249 int mru; /* Stored MRU */ 250 } PPPoEConnection; 251 252 /* Structure used to determine acceptable PADO or PADS packet */ 253 struct PacketCriteria { 254 PPPoEConnection *conn; 255 int acNameOK; 256 int serviceNameOK; 257 int seenACName; 258 int seenServiceName; 259 }; 260 261 /* Function Prototypes */ 262 UINT16_t etherType(PPPoEPacket *packet); 263 int openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr); 264 int sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size); 265 int receivePacket(int sock, PPPoEPacket *pkt, int *size); 266 void fatalSys(char const *str); 267 void rp_fatal(char const *str); 268 void printErr(char const *str); 269 void sysErr(char const *str); 270 void dumpPacket(FILE *fp, PPPoEPacket *packet, char const *dir); 271 void dumpHex(FILE *fp, unsigned char const *buf, int len); 272 int parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra); 273 void parseLogErrs(UINT16_t typ, UINT16_t len, unsigned char *data, void *xtra); 274 void syncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 275 void asyncReadFromPPP(PPPoEConnection *conn, PPPoEPacket *packet); 276 void asyncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 277 void syncReadFromEth(PPPoEConnection *conn, int sock, int clampMss); 278 char *strDup(char const *str); 279 void sendPADT(PPPoEConnection *conn, char const *msg); 280 void sendSessionPacket(PPPoEConnection *conn, 281 PPPoEPacket *packet, int len); 282 void initPPP(void); 283 void clampMSS(PPPoEPacket *packet, char const *dir, int clampMss); 284 UINT16_t computeTCPChecksum(unsigned char *ipHdr, unsigned char *tcpHdr); 285 UINT16_t pppFCS16(UINT16_t fcs, unsigned char *cp, int len); 286 void discovery(PPPoEConnection *conn); 287 unsigned char *findTag(PPPoEPacket *packet, UINT16_t tagType, 288 PPPoETag *tag); 289 290 void pppoe_printpkt(PPPoEPacket *packet, 291 void (*printer)(void *, char *, ...), void *arg); 292 void pppoe_log_packet(const char *prefix, PPPoEPacket *packet); 293 294 #define SET_STRING(var, val) do { if (var) free(var); var = strDup(val); } while(0); 295 296 #define CHECK_ROOM(cursor, start, len) \ 297 do {\ 298 if (((cursor)-(start))+(len) > MAX_PPPOE_PAYLOAD) { \ 299 error("Would create too-long packet"); \ 300 return; \ 301 } \ 302 } while(0) 303 304 /* True if Ethernet address is broadcast or multicast */ 305 #define NOT_UNICAST(e) ((e[0] & 0x01) != 0) 306 #define BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) == 0xFF) 307 #define NOT_BROADCAST(e) ((e[0] & e[1] & e[2] & e[3] & e[4] & e[5]) != 0xFF) 308