-/* Initialize frame types to RFC 2516 values. Some broken peers apparently
- use different frame types... sigh... */
-
-UINT16_t Eth_PPPOE_Discovery = ETH_PPPOE_DISCOVERY;
-UINT16_t Eth_PPPOE_Session = ETH_PPPOE_SESSION;
-
-/**********************************************************************
-*%FUNCTION: etherType
-*%ARGUMENTS:
-* packet -- a received PPPoE packet
-*%RETURNS:
-* ethernet packet type (see /usr/include/net/ethertypes.h)
-*%DESCRIPTION:
-* Checks the ethernet packet header to determine its type.
-* We should only be receveing DISCOVERY and SESSION types if the BPF
-* is set up correctly. Logs an error if an unexpected type is received.
-* Note that the ethernet type names come from "pppoe.h" and the packet
-* packet structure names use the LINUX dialect to maintain consistency
-* with the rest of this file. See the BSD section of "pppoe.h" for
-* translations of the data structure names.
-***********************************************************************/
-UINT16_t
-etherType(PPPoEPacket *packet)
-{
- UINT16_t type = (UINT16_t) ntohs(packet->ethHdr.h_proto);
- if (type != Eth_PPPOE_Discovery && type != Eth_PPPOE_Session) {
- fprintf(stderr, "Invalid ether type 0x%x\n", type);
- }
- return type;
-}
-
-/**********************************************************************
-*%FUNCTION: openInterface
-*%ARGUMENTS:
-* ifname -- name of interface
-* type -- Ethernet frame type
-* hwaddr -- if non-NULL, set to the hardware address
-*%RETURNS:
-* A raw socket for talking to the Ethernet card. Exits on error.
-*%DESCRIPTION:
-* Opens a raw Ethernet socket
-***********************************************************************/
-int
-openInterface(char const *ifname, UINT16_t type, unsigned char *hwaddr)
-{
- int optval=1;
- int fd;
- struct ifreq ifr;
- int domain, stype;
-
-#ifdef HAVE_STRUCT_SOCKADDR_LL
- struct sockaddr_ll sa;
-#else
- struct sockaddr sa;
-#endif
-
- memset(&sa, 0, sizeof(sa));
-
-#ifdef HAVE_STRUCT_SOCKADDR_LL
- domain = PF_PACKET;
- stype = SOCK_RAW;
-#else
- domain = PF_INET;
- stype = SOCK_PACKET;
-#endif
-
- if ((fd = socket(domain, stype, htons(type))) < 0) {
- /* Give a more helpful message for the common error case */
- if (errno == EPERM) {
- fatal("Cannot create raw socket -- pppoe must be run as root.");
- }
- fatalSys("socket");
- }
-
- if (setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &optval, sizeof(optval)) < 0) {
- fatalSys("setsockopt");
- }
-
- /* Fill in hardware address */
- if (hwaddr) {
- strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
- if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) {
- fatalSys("ioctl(SIOCGIFHWADDR)");
- }
- memcpy(hwaddr, ifr.ifr_hwaddr.sa_data, ETH_ALEN);
-#ifdef ARPHRD_ETHER
- if (ifr.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
- fatal("Interface %.16s is not Ethernet", ifname);
- }
-#endif
- if (NOT_UNICAST(hwaddr)) {
- fatal("Interface %.16s has broadcast/multicast MAC address??", ifname);
- }
- }
-
- /* Sanity check on MTU */
- strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
- if (ioctl(fd, SIOCGIFMTU, &ifr) < 0) {
- fatalSys("ioctl(SIOCGIFMTU)");
- }
- if (ifr.ifr_mtu < ETH_DATA_LEN) {
- fprintf(stderr, "Interface %.16s has MTU of %d -- should be %d.\n",
- ifname, ifr.ifr_mtu, ETH_DATA_LEN);
- fprintf(stderr, "You may have serious connection problems.\n");
- }
-
-#ifdef HAVE_STRUCT_SOCKADDR_LL
- /* Get interface index */
- sa.sll_family = AF_PACKET;
- sa.sll_protocol = htons(type);
-
- strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
- ifr.ifr_name[IFNAMSIZ - 1] = 0;
- if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0) {
- fatalSys("ioctl(SIOCFIGINDEX): Could not get interface index");
- }
- sa.sll_ifindex = ifr.ifr_ifindex;
-
-#else
- strcpy(sa.sa_data, ifname);
-#endif
-
- /* We're only interested in packets on specified interface */
- if (bind(fd, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
- fatalSys("bind");
- }
-
- return fd;
-}
-
-
-/***********************************************************************
-*%FUNCTION: sendPacket
-*%ARGUMENTS:
-* sock -- socket to send to
-* pkt -- the packet to transmit
-* size -- size of packet (in bytes)
-*%RETURNS:
-* 0 on success; -1 on failure
-*%DESCRIPTION:
-* Transmits a packet
-***********************************************************************/
-int
-sendPacket(PPPoEConnection *conn, int sock, PPPoEPacket *pkt, int size)
-{
-#if defined(HAVE_STRUCT_SOCKADDR_LL)
- if (send(sock, pkt, size, 0) < 0) {
- fatalSys("send (sendPacket)");
- return -1;
- }
-#else
- struct sockaddr sa;
-
- if (!conn) {
- fatal("relay and server not supported on Linux 2.0 kernels");
- }
- strcpy(sa.sa_data, conn->ifName);
- if (sendto(sock, pkt, size, 0, &sa, sizeof(sa)) < 0) {
- fatalSys("sendto (sendPacket)");
- return -1;
- }
-#endif
- return 0;
-}
-
-/***********************************************************************
-*%FUNCTION: receivePacket
-*%ARGUMENTS:
-* sock -- socket to read from
-* pkt -- place to store the received packet
-* size -- set to size of packet in bytes
-*%RETURNS:
-* >= 0 if all OK; < 0 if error
-*%DESCRIPTION:
-* Receives a packet
-***********************************************************************/
-int
-receivePacket(int sock, PPPoEPacket *pkt, int *size)
-{
- if ((*size = recv(sock, pkt, sizeof(PPPoEPacket), 0)) < 0) {
- fatalSys("recv (receivePacket)");
- return -1;
- }
- return 0;
-}
-
-/**********************************************************************
-*%FUNCTION: parsePacket
-*%ARGUMENTS:
-* packet -- the PPPoE discovery packet to parse
-* func -- function called for each tag in the packet
-* extra -- an opaque data pointer supplied to parsing function
-*%RETURNS:
-* 0 if everything went well; -1 if there was an error
-*%DESCRIPTION:
-* Parses a PPPoE discovery packet, calling "func" for each tag in the packet.
-* "func" is passed the additional argument "extra".
-***********************************************************************/
-int
-parsePacket(PPPoEPacket *packet, ParseFunc *func, void *extra)
-{
- UINT16_t len = ntohs(packet->length);
- unsigned char *curTag;
- UINT16_t tagType, tagLen;
-
- if (PPPOE_VER(packet->vertype) != 1) {
- fprintf(stderr, "Invalid PPPoE version (%d)\n",
- PPPOE_VER(packet->vertype));
- return -1;
- }
- if (PPPOE_TYPE(packet->vertype) != 1) {
- fprintf(stderr, "Invalid PPPoE type (%d)\n",
- PPPOE_TYPE(packet->vertype));
- return -1;
- }
-
- /* Do some sanity checks on packet */
- if (len > ETH_JUMBO_LEN - PPPOE_OVERHEAD) { /* 6-byte overhead for PPPoE header */
- fprintf(stderr, "Invalid PPPoE packet length (%u)\n", len);
- return -1;
- }
-
- /* Step through the tags */
- curTag = packet->payload;
- while(curTag - packet->payload < len) {
- /* Alignment is not guaranteed, so do this by hand... */
- tagType = (curTag[0] << 8) + curTag[1];
- tagLen = (curTag[2] << 8) + curTag[3];
- if (tagType == TAG_END_OF_LIST) {
- return 0;
- }
- if ((curTag - packet->payload) + tagLen + TAG_HDR_SIZE > len) {
- fprintf(stderr, "Invalid PPPoE tag length (%u)\n", tagLen);
- return -1;
- }
- func(tagType, tagLen, curTag+TAG_HDR_SIZE, extra);
- curTag = curTag + TAG_HDR_SIZE + tagLen;
- }
- return 0;
-}
-
-/**********************************************************************
-*%FUNCTION: parseForHostUniq
-*%ARGUMENTS:
-* type -- tag type
-* len -- tag length
-* data -- tag data.
-* extra -- user-supplied pointer. This is assumed to be a pointer to int.
-*%RETURNS:
-* Nothing
-*%DESCRIPTION:
-* If a HostUnique tag is found which matches our PID, sets *extra to 1.
-***********************************************************************/
-void
-parseForHostUniq(UINT16_t type, UINT16_t len, unsigned char *data,
- void *extra)
-{
- PPPoETag *tag = extra;
-
- if (type == TAG_HOST_UNIQ && len == ntohs(tag->length))
- tag->length = memcmp(data, tag->payload, len);
-}
-
-/**********************************************************************
-*%FUNCTION: packetIsForMe
-*%ARGUMENTS:
-* conn -- PPPoE connection info
-* packet -- a received PPPoE packet
-*%RETURNS:
-* 1 if packet is for this PPPoE daemon; 0 otherwise.
-*%DESCRIPTION:
-* If we are using the Host-Unique tag, verifies that packet contains
-* our unique identifier.
-***********************************************************************/
-int
-packetIsForMe(PPPoEConnection *conn, PPPoEPacket *packet)
-{
- PPPoETag hostUniq = conn->hostUniq;
-
- /* If packet is not directed to our MAC address, forget it */
- if (memcmp(packet->ethHdr.h_dest, conn->myEth, ETH_ALEN)) return 0;
-
- /* If we're not using the Host-Unique tag, then accept the packet */
- if (!conn->hostUniq.length) return 1;
-
- parsePacket(packet, parseForHostUniq, &hostUniq);
- return !hostUniq.length;
-}
-
-/**********************************************************************
-*%FUNCTION: parsePADOTags
-*%ARGUMENTS:
-* type -- tag type
-* len -- tag length
-* data -- tag data
-* extra -- extra user data. Should point to a PacketCriteria structure
-* which gets filled in according to selected AC name and service
-* name.
-*%RETURNS:
-* Nothing
-*%DESCRIPTION:
-* Picks interesting tags out of a PADO packet
-***********************************************************************/
-void
-parsePADOTags(UINT16_t type, UINT16_t len, unsigned char *data,
- void *extra)
-{
- struct PacketCriteria *pc = (struct PacketCriteria *) extra;
- PPPoEConnection *conn = pc->conn;
- int i;
-
- switch(type) {
- case TAG_AC_NAME:
- pc->seenACName = 1;
- if (pppoe_verbose >= 1) {
- printf("Access-Concentrator: %.*s\n", (int) len, data);
- }
- if (conn->acName && len == strlen(conn->acName) &&
- !strncmp((char *) data, conn->acName, len)) {
- pc->acNameOK = 1;
- }
- break;
- case TAG_SERVICE_NAME:
- pc->seenServiceName = 1;
- if (pppoe_verbose >= 1 && len > 0) {
- printf(" Service-Name: %.*s\n", (int) len, data);
- }
- if (conn->serviceName && len == strlen(conn->serviceName) &&
- !strncmp((char *) data, conn->serviceName, len)) {
- pc->serviceNameOK = 1;
- }
- break;
- case TAG_AC_COOKIE:
- if (pppoe_verbose >= 1) {
- printf("Got a cookie:");
- /* Print first 20 bytes of cookie */
- for (i=0; i<len && i < 20; i++) {
- printf(" %02x", (unsigned) data[i]);
- }
- if (i < len) printf("...");
- printf("\n");
- }
- conn->cookie.type = htons(type);
- conn->cookie.length = htons(len);
- memcpy(conn->cookie.payload, data, len);
- break;
- case TAG_RELAY_SESSION_ID:
- if (pppoe_verbose >= 1) {
- printf("Got a Relay-ID:");
- /* Print first 20 bytes of relay ID */
- for (i=0; i<len && i < 20; i++) {
- printf(" %02x", (unsigned) data[i]);
- }
- if (i < len) printf("...");
- printf("\n");
- }
- conn->relayId.type = htons(type);
- conn->relayId.length = htons(len);
- memcpy(conn->relayId.payload, data, len);
- break;
- case TAG_SERVICE_NAME_ERROR:
- if (pppoe_verbose >= 1) {
- printf("Got a Service-Name-Error tag: %.*s\n", (int) len, data);
- }
- break;
- case TAG_AC_SYSTEM_ERROR:
- if (pppoe_verbose >= 1) {
- printf("Got a System-Error tag: %.*s\n", (int) len, data);
- }
- break;
- case TAG_GENERIC_ERROR:
- if (pppoe_verbose >= 1) {
- printf("Got a Generic-Error tag: %.*s\n", (int) len, data);
- }
- break;
- }
-}
-
-/***********************************************************************
-*%FUNCTION: sendPADI
-*%ARGUMENTS:
-* conn -- PPPoEConnection structure
-*%RETURNS:
-* Nothing
-*%DESCRIPTION:
-* Sends a PADI packet
-***********************************************************************/
-void
-sendPADI(PPPoEConnection *conn)
-{
- PPPoEPacket packet;
- unsigned char *cursor = packet.payload;
- PPPoETag *svc = (PPPoETag *) (&packet.payload);
- UINT16_t namelen = 0;
- UINT16_t plen;
-
- if (conn->serviceName) {
- namelen = (UINT16_t) strlen(conn->serviceName);
- }
- plen = TAG_HDR_SIZE + namelen;
- CHECK_ROOM(cursor, packet.payload, plen);
-
- /* Set destination to Ethernet broadcast address */
- memset(packet.ethHdr.h_dest, 0xFF, ETH_ALEN);
- memcpy(packet.ethHdr.h_source, conn->myEth, ETH_ALEN);
-
- packet.ethHdr.h_proto = htons(Eth_PPPOE_Discovery);
- packet.vertype = PPPOE_VER_TYPE(1, 1);
- packet.code = CODE_PADI;
- packet.session = 0;
-
- svc->type = TAG_SERVICE_NAME;
- svc->length = htons(namelen);
- CHECK_ROOM(cursor, packet.payload, namelen+TAG_HDR_SIZE);
-
- if (conn->serviceName) {
- memcpy(svc->payload, conn->serviceName, strlen(conn->serviceName));
- }
- cursor += namelen + TAG_HDR_SIZE;
-
- /* If we're using Host-Uniq, copy it over */
- if (conn->hostUniq.length) {
- int len = ntohs(conn->hostUniq.length);
- CHECK_ROOM(cursor, packet.payload, len + TAG_HDR_SIZE);
- memcpy(cursor, &conn->hostUniq, len + TAG_HDR_SIZE);
- cursor += len + TAG_HDR_SIZE;
- plen += len + TAG_HDR_SIZE;
- }
-
- packet.length = htons(plen);
-
- sendPacket(conn, conn->discoverySocket, &packet, (int) (plen + HDR_SIZE));
- if (conn->debugFile) {
- dumpPacket(conn->debugFile, &packet, "SENT");
- fprintf(conn->debugFile, "\n");
- fflush(conn->debugFile);
- }
-}
-
-/**********************************************************************
-*%FUNCTION: waitForPADO
-*%ARGUMENTS:
-* conn -- PPPoEConnection structure
-* timeout -- how long to wait (in seconds)
-*%RETURNS:
-* Nothing
-*%DESCRIPTION:
-* Waits for a PADO packet and copies useful information
-***********************************************************************/
-void
-waitForPADO(PPPoEConnection *conn, int timeout)
-{
- fd_set readable;
- int r;
- struct timeval tv;
- PPPoEPacket packet;
- int len;
-
- struct PacketCriteria pc;
- pc.conn = conn;
- pc.acNameOK = (conn->acName) ? 0 : 1;
- pc.serviceNameOK = (conn->serviceName) ? 0 : 1;
- pc.seenACName = 0;
- pc.seenServiceName = 0;
- conn->error = 0;
-
- do {
- if (BPF_BUFFER_IS_EMPTY) {
- tv.tv_sec = timeout;
- tv.tv_usec = 0;
-
- FD_ZERO(&readable);
- FD_SET(conn->discoverySocket, &readable);
-
- while(1) {
- r = select(conn->discoverySocket+1, &readable, NULL, NULL, &tv);
- if (r >= 0 || errno != EINTR) break;
- }
- if (r < 0) {
- perror("select (waitForPADO)");
- return;
- }
- if (r == 0) return; /* Timed out */
- }
-
- /* Get the packet */
- receivePacket(conn->discoverySocket, &packet, &len);
-
- /* Check length */
- if (ntohs(packet.length) + HDR_SIZE > len) {
- fprintf(stderr, "Bogus PPPoE length field (%u)\n",
- (unsigned int) ntohs(packet.length));
- continue;
- }
-
-#ifdef USE_BPF
- /* If it's not a Discovery packet, loop again */
- if (etherType(&packet) != Eth_PPPOE_Discovery) continue;
-#endif
-
- if (conn->debugFile) {
- dumpPacket(conn->debugFile, &packet, "RCVD");
- fprintf(conn->debugFile, "\n");
- fflush(conn->debugFile);
- }
- /* If it's not for us, loop again */
- if (!packetIsForMe(conn, &packet)) continue;
-
- if (packet.code == CODE_PADO) {
- if (BROADCAST(packet.ethHdr.h_source)) {
- fprintf(stderr, "Ignoring PADO packet from broadcast MAC address\n");
- continue;
- }
- parsePacket(&packet, parsePADOTags, &pc);
- if (conn->error)
- return;
- if (!pc.seenACName) {
- fprintf(stderr, "Ignoring PADO packet with no AC-Name tag\n");
- continue;
- }
- if (!pc.seenServiceName) {
- fprintf(stderr, "Ignoring PADO packet with no Service-Name tag\n");
- continue;
- }
- conn->numPADOs++;
- if (pc.acNameOK && pc.serviceNameOK) {
- memcpy(conn->peerEth, packet.ethHdr.h_source, ETH_ALEN);
- if (pppoe_verbose >= 1) {
- printf("AC-Ethernet-Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
- (unsigned) conn->peerEth[0],
- (unsigned) conn->peerEth[1],
- (unsigned) conn->peerEth[2],
- (unsigned) conn->peerEth[3],
- (unsigned) conn->peerEth[4],
- (unsigned) conn->peerEth[5]);
- printf("--------------------------------------------------\n");
- continue;
- }
- conn->discoveryState = STATE_RECEIVED_PADO;
- break;
- }
- }
- } while (conn->discoveryState != STATE_RECEIVED_PADO);
-}
-
-/**********************************************************************
-*%FUNCTION: discovery
-*%ARGUMENTS:
-* conn -- PPPoE connection info structure
-*%RETURNS:
-* Nothing
-*%DESCRIPTION:
-* Performs the PPPoE discovery phase
-***********************************************************************/
-void
-discovery(PPPoEConnection *conn)
-{
- int padiAttempts = 0;
- int timeout = conn->discoveryTimeout;
-
- conn->discoverySocket =
- openInterface(conn->ifName, Eth_PPPOE_Discovery, conn->myEth);
-
- do {
- padiAttempts++;
- if (padiAttempts > conn->discoveryAttempts) {
- fprintf(stderr, "Timeout waiting for PADO packets\n");
- close(conn->discoverySocket);
- conn->discoverySocket = -1;
- return;
- }
- sendPADI(conn);
- conn->discoveryState = STATE_SENT_PADI;
- waitForPADO(conn, timeout);
- } while (!conn->numPADOs);
-}
-