X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/2643262af427335dc93eb4a8460bcd7338bbd2ed..b4ca67c68b8408f29144d78c75613715fab77741:/ppp.c?ds=sidebyside diff --git a/ppp.c b/ppp.c index e870704..4fe4f6a 100644 --- a/ppp.c +++ b/ppp.c @@ -1,6 +1,6 @@ // L2TPNS PPP Stuff -char const *cvs_id_ppp = "$Id: ppp.c,v 1.66 2005-08-10 08:04:26 bodea Exp $"; +char const *cvs_id_ppp = "$Id: ppp.c,v 1.96 2006-02-17 15:05:14 bodea Exp $"; #include #include @@ -26,7 +26,7 @@ extern configt *config; static int add_lcp_auth(uint8_t *b, int size, int authtype); // Process PAP messages -void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { char user[MAXUSER]; char pass[MAXPASS]; @@ -85,13 +85,12 @@ void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) LOG(3, s, t, "PAP login %s/%s\n", user, pass); } - r = radiusnew(s); - if (session[s].ip || !r) + if (session[s].ip || !(r = radiusnew(s))) { // respond now, either no RADIUS available or already authenticated - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint8_t id = p[1]; - uint8_t *p = makeppp(b, sizeof(b), 0, 0, t, s, PPPPAP); + uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP); if (!p) return; if (session[s].ip) @@ -140,7 +139,7 @@ void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) } // Process CHAP messages -void processchap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { uint16_t r; uint16_t hl; @@ -148,13 +147,6 @@ void processchap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) CSTAT(processchap); LOG_HEX(5, "CHAP", p, l); - r = sess_local[s].radius; - if (!r) - { - LOG(1, s, t, "Unexpected CHAP message\n"); - STAT(tunnel_rx_errors); - return; - } if (l < 4) { @@ -181,6 +173,13 @@ void processchap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } + r = sess_local[s].radius; + if (!r) + { + LOG(3, s, t, "Unexpected CHAP message\n"); + return; + } + if (session[s].ppp.phase != Authenticate) { LOG(2, s, t, "CHAP ignored in %s phase\n", ppp_phase(session[s].ppp.phase)); @@ -301,7 +300,7 @@ static void dumplcp(uint8_t *p, int l) else if (length == 5) { int proto = ntohs(*(uint16_t *)(o + 2)); - int algo = *(uint8_t *)(o + 4); + int algo = *(o + 4); LOG(4, 0, 0, " %s 0x%x 0x%x (%s)\n", ppp_lcp_option(type), proto, algo, (proto == PPPCHAP && algo == 5) ? "CHAP MD5" : "UNSUPPORTED"); } @@ -336,23 +335,25 @@ static void dumplcp(uint8_t *p, int l) } } -void lcp_open(tunnelidt t, sessionidt s) +void lcp_open(sessionidt s, tunnelidt t) { // transition to Authentication or Network phase: session[s].ppp.phase = sess_local[s].lcp_authtype ? Authenticate : Network; + LOG(3, s, t, "LCP: Opened, phase %s\n", ppp_phase(session[s].ppp.phase)); + // LCP now Opened change_state(s, lcp, Opened); if (session[s].ppp.phase == Authenticate) { if (sess_local[s].lcp_authtype == AUTHCHAP) - sendchap(t, s); + sendchap(s, t); } else { // This-Layer-Up - sendipcp(t, s); + sendipcp(s, t); change_state(s, ipcp, RequestSent); // move to passive state for IPv6 (if configured), CCP if (config->ipv6_prefix.s6_addr[0]) @@ -373,12 +374,12 @@ static void lcp_restart(sessionidt s) change_state(s, ccp, Dead); } -static uint8_t *ppp_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, +static uint8_t *ppp_conf_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option) { if (!*response || **response != ConfigRej) { - queued = *response = makeppp(buf, blen, packet, 2, session[s].tunnel, s, mtype); + queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype); if (!queued) return 0; @@ -396,7 +397,7 @@ static uint8_t *ppp_rej(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, return queued + option[1]; } -static uint8_t *ppp_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, +static uint8_t *ppp_conf_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, uint8_t **response, uint8_t *queued, uint8_t *packet, uint8_t *option, uint8_t *value, size_t vlen) { @@ -414,19 +415,19 @@ static uint8_t *ppp_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, if (*nak_sent < config->ppp_max_failure) // reject queued return queued; - return ppp_rej(s, buf, blen, mtype, response, 0, packet, option); + return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option); } if (!*response) { if (*nak_sent >= config->ppp_max_failure) - return ppp_rej(s, buf, blen, mtype, response, 0, packet, option); + return ppp_conf_rej(s, buf, blen, mtype, response, 0, packet, option); - queued = *response = makeppp(buf, blen, packet, 2, session[s].tunnel, s, mtype); + queued = *response = makeppp(buf, blen, packet, 2, s, session[s].tunnel, mtype); if (!queued) return 0; - *nak_sent++; + (*nak_sent)++; *queued = ConfigNak; queued += 4; } @@ -443,12 +444,37 @@ static uint8_t *ppp_nak(sessionidt s, uint8_t *buf, size_t blen, uint16_t mtype, return queued + vlen; } +static void ppp_code_rej(sessionidt s, tunnelidt t, uint16_t proto, + char *pname, uint8_t *p, uint16_t l, uint8_t *buf, size_t size) +{ + uint8_t *q; + int mru = session[s].mru; + if (mru < MINMTU) mru = MINMTU; + if (mru > size) mru = size; + + l += 4; + if (l > mru) l = mru; + + q = makeppp(buf, size, 0, 0, s, t, proto); + if (!q) return; + + *q = CodeRej; + *(q + 1) = ++sess_local[s].lcp_ident; + *(uint16_t *)(q + 2) = htons(l); + memcpy(q + 4, p, l - 4); + + LOG(2, s, t, "Unexpected %s code %s\n", pname, ppp_code(*p)); + LOG(3, s, t, "%s: send %s\n", pname, ppp_code(*q)); + if (config->debug > 3) dumplcp(q, l); + + tunnelsend(buf, l + (q - buf), t); +} + // Process LCP messages -void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint8_t *q = NULL; - uint32_t magicno = 0; uint16_t hl; CSTAT(processlcp); @@ -472,15 +498,17 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) if (session[s].die) // going down... return; + LOG((*p == EchoReq || *p == EchoReply) ? 4 : 3, s, t, + "LCP: recv %s\n", ppp_code(*p)); + + if (config->debug > 3) dumplcp(p, l); + if (*p == ConfigAck) { int x = l - 4; uint8_t *o = (p + 4); int authtype = 0; - LOG(3, s, t, "LCP: ConfigAck (%d bytes)...\n", l); - if (config->debug > 3) dumplcp(p, l); - while (x > 2) { int type = o[0]; @@ -520,12 +548,12 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) if (session[s].ppp.lcp == Opened) lcp_restart(s); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); change_state(s, lcp, RequestSent); break; case AckSent: - lcp_open(t, s); + lcp_open(s, t); break; default: @@ -540,9 +568,6 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero static uint8_t authproto[5]; - LOG(3, s, t, "LCP: ConfigReq (%d bytes)...\n", l); - if (config->debug > 3) dumplcp(p, l); - while (x > 2) { int type = o[0]; @@ -552,15 +577,27 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) switch (type) { case 1: // Maximum-Receive-Unit - session[s].mru = ntohs(*(uint16_t *)(o + 2)); + { + uint16_t mru = ntohs(*(uint16_t *)(o + 2)); + if (mru >= MINMTU) + { + session[s].mru = mru; + cluster_send_session(s); + break; + } + + LOG(3, s, t, " Remote requesting MRU of %u. Rejecting.\n", mru); + mru = htons(MRU); + q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, (uint8_t *) &mru, sizeof(mru)); + } break; case 2: // Async-Control-Character-Map if (!ntohl(*(uint32_t *)(o + 2))) // all bits zero is OK break; - LOG(2, s, t, " Remote requesting asyncmap. Rejecting.\n"); - q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap)); + LOG(3, s, t, " Remote requesting asyncmap. Rejecting.\n"); + q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, asyncmap, sizeof(asyncmap)); break; case 3: // Authentication-Protocol @@ -593,37 +630,34 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) else sprintf(proto_name, "%#4.4x", proto); - LOG(2, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name); + LOG(3, s, t, " Remote requesting %s authentication. Rejecting.\n", proto_name); alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authprefer); if (alen < 2) break; // paranoia - q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2); + q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2); if (q && *response == ConfigNak && config->radius_authtypes != config->radius_authprefer) { // alternate type alen = add_lcp_auth(authproto, sizeof(authproto), config->radius_authtypes & ~config->radius_authprefer); if (alen < 2) break; - q = ppp_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2); + q = ppp_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2); } break; } break; - case 5: // Magic-Number - magicno = ntohl(*(uint32_t *)(o + 2)); - break; - case 4: // Quality-Protocol + case 5: // Magic-Number case 7: // Protocol-Field-Compression case 8: // Address-And-Control-Field-Compression break; default: // Reject any unknown options - LOG(2, s, t, " Rejecting PPP LCP Option type %d\n", type); - q = ppp_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o); + LOG(3, s, t, " Rejecting unknown PPP LCP option %d\n", type); + q = ppp_conf_rej(s, b, sizeof(b), PPPLCP, &response, q, p, o); } x -= length; o += length; @@ -637,7 +671,7 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) else { // Send packet back as ConfigAck - response = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); + response = makeppp(b, sizeof(b), p, l, s, t, PPPLCP); if (!response) return; *response = ConfigAck; } @@ -645,7 +679,7 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) switch (session[s].ppp.lcp) { case Closed: - response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP); + response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP); if (!response) return; *response = TerminateAck; *((uint16_t *) (response + 2)) = htons(l = 4); @@ -653,7 +687,7 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case Stopped: initialise_restart_count(s, lcp); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); if (*response == ConfigAck) change_state(s, lcp, AckSent); else @@ -669,13 +703,13 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case AckReceived: if (*response == ConfigAck) - lcp_open(t, s); + lcp_open(s, t); break; case Opened: lcp_restart(s); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); /* fallthrough */ case AckSent: @@ -691,18 +725,17 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } - LOG(3, s, t, "LCP: Sending %s\n", ppp_code(*response)); + LOG(3, s, t, "LCP: send %s\n", ppp_code(*response)); + if (config->debug > 3) dumplcp(response, l); + tunnelsend(b, l + (response - b), t); } - else if (*p == ConfigNak) + else if (*p == ConfigNak || *p == ConfigRej) { int x = l - 4; uint8_t *o = (p + 4); int authtype = -1; - LOG(3, s, t, "LCP: ConfigNak (%d bytes)...\n", l); - if (config->debug > 3) dumplcp(p, l); - while (x > 2) { int type = o[0]; @@ -712,23 +745,38 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) switch (type) { case 1: // Maximum-Receive-Unit - session[s].mru = ntohs(*(uint16_t *)(o + 2)); - LOG(3, s, t, " Remote requested MRU of %u\n", session[s].mru); + if (*p == ConfigNak) + { + if (length < 4) break; + sess_local[s].ppp_mru = ntohs(*(uint16_t *)(o + 2)); + LOG(3, s, t, " Remote requested MRU of %u\n", sess_local[s].ppp_mru); + } + else + { + sess_local[s].ppp_mru = 0; + LOG(3, s, t, " Remote rejected MRU negotiation\n"); + } + break; case 3: // Authentication-Protocol if (authtype > 0) break; + if (*p == ConfigNak) { - int proto = ntohs(*(uint16_t *)(o + 2)); + int proto; + + if (length < 4) break; + proto = ntohs(*(uint16_t *)(o + 2)); + if (proto == PPPPAP) { authtype = config->radius_authtypes & AUTHPAP; LOG(3, s, t, " Remote requested PAP authentication...%sing\n", authtype ? "accept" : "reject"); } - else if (proto == PPPCHAP && *(o + 4) == 5) + else if (proto == PPPCHAP && length > 4 && *(o + 4) == 5) { authtype = config->radius_authtypes & AUTHCHAP; LOG(3, s, t, " Remote requested CHAP authentication...%sing\n", @@ -740,12 +788,34 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) proto); } } + else + { + LOG(2, s, t, "LCP: remote rejected auth negotiation\n"); + authtype = 0; // shutdown + } break; - default: - LOG(2, s, t, " Remote NAKed LCP type %u?\n", type); + case 5: // Magic-Number + session[s].magic = 0; + if (*p == ConfigNak) + { + if (length < 6) break; + session[s].magic = ntohl(*(uint32_t *)(o + 2)); + } + + if (session[s].magic) + LOG(3, s, t, " Remote requested magic-no %x\n", session[s].magic); + else + LOG(3, s, t, " Remote rejected magic-no\n"); + + cluster_send_session(s); break; + + default: + LOG(2, s, t, "LCP: remote sent %s for type %u?\n", ppp_code(*p), type); + sessionshutdown(s, "Unable to negotiate LCP.", 3, 0); + return; } x -= length; o += length; @@ -765,10 +835,14 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case Closed: case Stopped: { - uint8_t *response = makeppp(b, sizeof(b), p, 2, t, s, PPPLCP); + uint8_t *response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP); if (!response) return; *response = TerminateAck; *((uint16_t *) (response + 2)) = htons(l = 4); + + LOG(3, s, t, "LCP: send %s\n", ppp_code(*response)); + if (config->debug > 3) dumplcp(response, l); + tunnelsend(b, l + (response - b), t); } break; @@ -776,17 +850,17 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case RequestSent: case AckSent: initialise_restart_count(s, lcp); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); break; case AckReceived: LOG(2, s, t, "LCP: ConfigNak in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp)); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); break; case Opened: lcp_restart(s); - sendlcp(s, t, sess_local[s].lcp_authtype); + sendlcp(s, t); break; default: @@ -796,10 +870,13 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) } else if (*p == TerminateReq) { - LOG(3, s, t, "LCP: Received TerminateReq. Sending TerminateAck\n"); *p = TerminateAck; // close - q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP); if (!q) return; + + LOG(3, s, t, "LCP: send %s\n", ppp_code(*q)); + if (config->debug > 3) dumplcp(q, l); + tunnelsend(b, l + (q - b), t); // send it sessionshutdown(s, "Remote end closed connection.", 3, 0); } @@ -809,74 +886,81 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) } else if (*p == ProtocolRej) { - if (*(uint16_t *) (p+4) == htons(PPPIPV6CP)) + uint16_t proto = 0; + + if (l > 4) + { + proto = *(p+4); + if (l > 5 && !(proto & 1)) + { + proto <<= 8; + proto |= *(p+5); + } + } + + if (proto == PPPIPV6CP) { LOG(3, s, t, "IPv6 rejected\n"); change_state(s, ipv6cp, Closed); } else { - LOG(1, s, t, "Unexpected LCP protocol reject 0x%X\n", - ntohs(*(uint16_t *) (p+4))); - STAT(tunnel_rx_errors); + LOG(3, s, t, "LCP protocol reject: 0x%04X\n", proto); } } else if (*p == EchoReq) { - LOG(5, s, t, "LCP: Received EchoReq. Sending EchoReply\n"); *p = EchoReply; // reply *(uint32_t *) (p + 4) = htonl(session[s].magic); // our magic number - q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP); if (!q) return; + + LOG(4, s, t, "LCP: send %s\n", ppp_code(*q)); + if (config->debug > 3) dumplcp(q, l); + tunnelsend(b, l + (q - b), t); // send it } else if (*p == EchoReply) { // Ignore it, last_packet time is set earlier than this. } - else + else if (*p != CodeRej) { - int code = *p; - int mru = session[s].mru; - if (!mru) - mru = DEFAULT_MRU; - - if (l > mru) l = mru; - - *p = CodeRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); - if (!q) return; - - LOG(3, s, t, "Unexpected LCP code %s\n", ppp_code(code)); - tunnelsend(b, l + (q - b), t); + ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b)); } } -static void ipcp_open(tunnelidt t, sessionidt s) +static void ipcp_open(sessionidt s, tunnelidt t) { - LOG(3, s, t, "IPCP Acked, session is now active\n"); + LOG(3, s, t, "IPCP: Opened, session is now active\n"); change_state(s, ipcp, Opened); - if (!session[s].walled_garden) + if (!(session[s].walled_garden || session[s].flags & SESSION_STARTED)) { uint16_t r = radiusnew(s); if (r) + { radiussend(r, RADIUSSTART); // send radius start + + // don't send further Start records if IPCP is restarted + session[s].flags |= SESSION_STARTED; + cluster_send_session(s); + } } // start IPv6 if configured and still in passive state if (session[s].ppp.ipv6cp == Stopped) { - sendipv6cp(t, s); + sendipv6cp(s, t); change_state(s, ipv6cp, RequestSent); } } // Process IPCP messages -void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint8_t *q = 0; uint16_t hl; @@ -904,6 +988,8 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } + LOG(3, s, t, "IPCP: recv %s\n", ppp_code(*p)); + if (*p == ConfigAck) { switch (session[s].ppp.ipcp) @@ -921,7 +1007,7 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) break; case AckSent: - ipcp_open(t, s); + ipcp_open(s, t); break; default: @@ -936,21 +1022,22 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) int gotip = 0; in_addr_t addr; - LOG(3, s, t, "IPCP ConfigReq received\n"); - while (length > 2) { + if (!o[1] || o[1] > length) return; + switch (*o) { case 3: // ip address gotip++; // seen address - if (o[1] != 6 || o[1] > length) return; + if (o[1] != 6) return; addr = htonl(session[s].ip); if (memcmp(o + 2, &addr, (sizeof addr))) { - q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); - if (!q || *response == ConfigRej) + uint8_t *oq = q; + q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); + if (!q || (q != oq && *response == ConfigRej)) { sessionshutdown(s, "Can't negotiate IPCP.", 3, 0); return; @@ -960,24 +1047,24 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) break; case 129: // primary DNS - if (o[1] != 6 || o[1] > length) return; + if (o[1] != 6) return; addr = htonl(session[s].dns1); if (memcmp(o + 2, &addr, (sizeof addr))) { - q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); + q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); if (!q) return; } break; case 131: // secondary DNS - if (o[1] != 6 || o[1] > length) return; + if (o[1] != 6) return; - addr = htonl(session[s].dns1); + addr = htonl(session[s].dns2); if (memcmp(o + 2, &addr, sizeof(addr))) { - q = ppp_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); + q = ppp_conf_nak(s, b, sizeof(b), PPPIPCP, &response, q, p, o, (uint8_t *) &addr, sizeof(addr)); if (!q) return; } @@ -985,7 +1072,7 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) default: LOG(2, s, t, " Rejecting PPP IPCP Option type %d\n", *o); - q = ppp_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o); + q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o); if (!q) return; } @@ -1001,7 +1088,7 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) else if (gotip) { // Send packet back as ConfigAck - response = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP); + response = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP); if (!response) return; *response = ConfigAck; } @@ -1015,7 +1102,7 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) switch (session[s].ppp.ipcp) { case Closed: - response = makeppp(b, sizeof(b), p, 2, t, s, PPPIPCP); + response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPCP); if (!response) return; *response = TerminateAck; *((uint16_t *) (response + 2)) = htons(l = 4); @@ -1039,7 +1126,7 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case AckReceived: if (*response == ConfigAck) - ipcp_open(t, s); + ipcp_open(s, t); break; @@ -1061,52 +1148,40 @@ void processipcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } - LOG(3, s, t, "IPCP: Sending %s\n", ppp_code(*response)); + LOG(3, s, t, "IPCP: send %s\n", ppp_code(*response)); tunnelsend(b, l + (response - b), t); } else if (*p == TerminateReq) { - LOG(3, s, t, "IPCP: Received TerminateReq. Sending TerminateAck\n"); *p = TerminateAck; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP); if (!q) return; + LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q)); tunnelsend(b, l + (q - b), t); change_state(s, ipcp, Stopped); } - else + else if (*p != CodeRej) { - int code = *p; - int mru = session[s].mru; - if (!mru) - mru = DEFAULT_MRU; - - if (l > mru) l = mru; - - *p = CodeRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP); - if (!q) return; - - LOG(3, s, t, "Unexpected IPCP code %s\n", ppp_code(code)); - tunnelsend(b, l + (q - b), t); + ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b)); } } -static void ipv6cp_open(tunnelidt t, sessionidt s) +static void ipv6cp_open(sessionidt s, tunnelidt t) { - LOG(3, s, t, "IPV6CP Acked\n"); + LOG(3, s, t, "IPV6CP: Opened\n"); change_state(s, ipv6cp, Opened); if (session[s].ipv6prefixlen) route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 1); // Send an initial RA (TODO: Should we send these regularly?) - send_ipv6_ra(t, s, NULL); + send_ipv6_ra(s, t, NULL); } // Process IPV6CP messages -void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint8_t *q = 0; uint16_t hl; @@ -1134,15 +1209,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } - if (!config->ipv6_prefix.s6_addr[0]) - { - LOG(2, s, t, "IPV6CP %s rejected (not configured)\n", ppp_code(*p)); - *p = ProtocolRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP); - if (!q) return; - tunnelsend(b, l + (q - b), t); - return; - } + LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p)); if (!session[s].ip) { @@ -1167,7 +1234,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) break; case AckSent: - ipv6cp_open(t, s); + ipv6cp_open(s, t); break; default: @@ -1182,22 +1249,22 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) int gotip = 0; uint8_t ident[8]; - LOG(3, s, t, "IPV6CP ConfigReq received\n"); - while (length > 2) { + if (!o[1] || o[1] > length) return; + switch (*o) { case 1: // interface identifier gotip++; // seen address - if (o[1] != 10 || o[1] > length) return; + if (o[1] != 10) return; *(uint32_t *) ident = htonl(session[s].ip); *(uint32_t *) (ident + 4) = 0; if (memcmp(o + 2, ident, sizeof(ident))) { - q = ppp_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident)); + q = ppp_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident)); if (!q) return; } @@ -1205,7 +1272,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) default: LOG(2, s, t, " Rejecting PPP IPV6CP Option type %d\n", *o); - q = ppp_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o); + q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o); if (!q) return; } @@ -1221,7 +1288,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) else if (gotip) { // Send packet back as ConfigAck - response = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP); + response = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP); if (!response) return; *response = ConfigAck; } @@ -1235,7 +1302,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) switch (session[s].ppp.ipv6cp) { case Closed: - response = makeppp(b, sizeof(b), p, 2, t, s, PPPIPV6CP); + response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPV6CP); if (!response) return; *response = TerminateAck; *((uint16_t *) (response + 2)) = htons(l = 4); @@ -1259,7 +1326,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) case AckReceived: if (*response == ConfigAck) - ipv6cp_open(t, s); + ipv6cp_open(s, t); break; @@ -1281,33 +1348,21 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } - LOG(3, s, t, "IPV6CP: Sending %s\n", ppp_code(*response)); + LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*response)); tunnelsend(b, l + (response - b), t); } else if (*p == TerminateReq) { - LOG(3, s, t, "IPV6CP: Received TerminateReq. Sending TerminateAck\n"); *p = TerminateAck; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP); if (!q) return; + LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q)); tunnelsend(b, l + (q - b), t); change_state(s, ipv6cp, Stopped); } - else + else if (*p != CodeRej) { - int code = *p; - int mru = session[s].mru; - if (!mru) - mru = DEFAULT_MRU; - - if (l > mru) l = mru; - - *p = CodeRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPV6CP); - if (!q) return; - - LOG(3, s, t, "Unexpected IPV6CP code %s\n", ppp_code(code)); - tunnelsend(b, l + (q - b), t); + ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b)); } } @@ -1315,7 +1370,7 @@ void processipv6cp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) // // This MUST be called with at least 4 byte behind 'p'. // (i.e. this routine writes to p[-4]). -void processipin(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { in_addr_t ip; @@ -1323,6 +1378,13 @@ void processipin(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) LOG_HEX(5, "IP", p, l); + if (l < 20) + { + LOG(1, s, t, "IP packet too short %d\n", l); + STAT(tunnel_rx_errors); + return ; + } + ip = ntohl(*(uint32_t *)(p + 12)); if (l > MAXETHER) @@ -1346,6 +1408,14 @@ void processipin(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) if (session[s].filter_in && !ip_filter(p, l, session[s].filter_in - 1)) return; + // adjust MSS on SYN and SYN,ACK packets with options + if ((ntohs(*(uint16_t *) (p + 6)) & 0x1fff) == 0 && p[9] == IPPROTO_TCP) // first tcp fragment + { + int ihl = (p[0] & 0xf) * 4; // length of IP header + if (l >= ihl + 20 && (p[ihl + 13] & TCP_FLAG_SYN) && ((p[ihl + 12] >> 4) > 5)) + adjust_tcp_mss(s, t, p, l, p + ihl); + } + // Add on the tun header p -= 4; *(uint32_t *) p = htonl(PKTIP); @@ -1401,7 +1471,7 @@ void processipin(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) // // This MUST be called with at least 4 byte behind 'p'. // (i.e. this routine writes to p[-4]). -void processipv6in(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { struct in6_addr ip; in_addr_t ipv4; @@ -1438,7 +1508,7 @@ void processipv6in(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) *(uint32_t *)(p + 34) == 0 && *(p + 38) == 0 && *(p + 39) == 2 && *(p + 40) == 133) { LOG(3, s, t, "Got IPv6 RS\n"); - send_ipv6_ra(t, s, &ip); + send_ipv6_ra(s, t, &ip); return; } @@ -1535,9 +1605,9 @@ void send_ipin(sessionidt s, uint8_t *buf, int len) // Process CCP messages -void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) +void processccp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l) { - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint8_t *q; CSTAT(processccp); @@ -1556,6 +1626,7 @@ void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) STAT(tunnel_rx_errors); } + LOG(3, s, t, "CCP: recv %s\n", ppp_code(*p)); if (*p == ConfigAck) { switch (session[s].ppp.ccp) @@ -1573,7 +1644,7 @@ void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) break; case AckSent: - LOG(3, s, t, "CCP Acked\n"); + LOG(3, s, t, "CCP: Opened\n"); change_state(s, ccp, Opened); break; @@ -1588,13 +1659,13 @@ void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) else // compression requested--reject *p = ConfigRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP); if (!q) return; switch (session[s].ppp.ccp) { case Closed: - q = makeppp(b, sizeof(b), p, 2, t, s, PPPCCP); + q = makeppp(b, sizeof(b), p, 2, s, t, PPPCCP); if (!q) return; *q = TerminateAck; *((uint16_t *) (q + 2)) = htons(l = 4); @@ -1640,40 +1711,28 @@ void processccp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l) return; } - LOG(3, s, t, "CCP: Sending %s\n", ppp_code(*q)); + LOG(3, s, t, "CCP: send %s\n", ppp_code(*q)); tunnelsend(b, l + (q - b), t); } else if (*p == TerminateReq) { - LOG(3, s, t, "CCP: Received TerminateReq. Sending TerminateAck\n"); *p = TerminateAck; - q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP); + q = makeppp(b, sizeof(b), p, l, s, t, PPPCCP); if (!q) return; + LOG(3, s, t, "CCP: send %s\n", ppp_code(*q)); tunnelsend(b, l + (q - b), t); change_state(s, ccp, Stopped); } - else + else if (*p != CodeRej) { - int code = *p; - int mru = session[s].mru; - if (!mru) - mru = DEFAULT_MRU; - - if (l > mru) l = mru; - - *p = CodeRej; - q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP); - if (!q) return; - - LOG(3, s, t, "Unexpected CCP code %s\n", ppp_code(code)); - tunnelsend(b, l + (q - b), t); + ppp_code_rej(s, t, PPPCCP, "CCP", p, l, b, sizeof(b)); } } // send a CHAP challenge -void sendchap(tunnelidt t, sessionidt s) +void sendchap(sessionidt s, tunnelidt t) { - uint8_t b[MAXCONTROL]; + uint8_t b[MAXETHER]; uint16_t r; uint8_t *q; @@ -1702,7 +1761,7 @@ void sendchap(tunnelidt t, sessionidt s) STAT(tunnel_tx_errors); return ; } - q = makeppp(b, sizeof(b), 0, 0, t, s, PPPCHAP); + q = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP); if (!q) return; *q = 1; // challenge @@ -1715,15 +1774,12 @@ void sendchap(tunnelidt t, sessionidt s) } // fill in a L2TP message with a PPP frame, -// copies existing PPP message and changes magic number if seen // returns start of PPP frame -uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, tunnelidt t, sessionidt s, uint16_t mtype) +uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype) { if (size < 12) // Need more space than this!! { - static int backtrace_count = 0; LOG(0, s, t, "makeppp buffer too small for L2TP header (size=%d)\n", size); - log_backtrace(backtrace_count, 5) return NULL; } @@ -1731,12 +1787,12 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, tunnelidt t, sessionid *(uint16_t *) (b + 2) = htons(tunnel[t].far); // tunnel *(uint16_t *) (b + 4) = htons(session[s].far); // session b += 6; - if (mtype == PPPLCP || !(session[s].l2tp_flags & SESSIONACFC)) + if (mtype == PPPLCP || !(session[s].flags & SESSION_ACFC)) { *(uint16_t *) b = htons(0xFF03); // HDLC header b += 2; } - if (mtype < 0x100 && session[s].l2tp_flags & SESSIONPFC) + if (mtype < 0x100 && session[s].flags & SESSION_PFC) *b++ = mtype; else { @@ -1746,9 +1802,7 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, tunnelidt t, sessionid if (l + 12 > size) { - static int backtrace_count = 0; LOG(2, s, t, "makeppp would overflow buffer (size=%d, header+payload=%d)\n", size, l + 12); - log_backtrace(backtrace_count, 5) return NULL; } @@ -1784,56 +1838,96 @@ static int add_lcp_auth(uint8_t *b, int size, int authtype) return len; } -// Send initial LCP ConfigReq for MRU, authentication type and magic no -void sendlcp(tunnelidt t, sessionidt s, int authtype) +// Send LCP ConfigReq for MRU, authentication type and magic no +void sendlcp(sessionidt s, tunnelidt t) { uint8_t b[500], *q, *l; + int authtype = sess_local[s].lcp_authtype; - if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP))) + if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPLCP))) return; - LOG(4, s, t, "Sending LCP ConfigReq%s%s\n", - authtype ? " for " : "", - authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : ""); - - if (!session[s].mru) - session[s].mru = DEFAULT_MRU; + LOG(3, s, t, "LCP: send ConfigReq%s%s%s\n", + authtype ? " (" : "", + authtype ? (authtype == AUTHCHAP ? "CHAP" : "PAP") : "", + authtype ? ")" : ""); l = q; *l++ = ConfigReq; - *l++ = (time_now % 255) + 1; // ID + *l++ = ++sess_local[s].lcp_ident; // ID l += 2; //Save space for length - *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4) - *(uint16_t *) l = htons(session[s].mru); l += 2; + if (sess_local[s].ppp_mru) + { + *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4) + *(uint16_t *) l = htons(sess_local[s].ppp_mru); l += 2; + } if (authtype) l += add_lcp_auth(l, sizeof(b) - (l - b), authtype); - *l++ = 5; *l++ = 6; // Magic-Number (length 6) - *(uint32_t *) l = htonl(session[s].magic); - l += 4; + if (session[s].magic) + { + *l++ = 5; *l++ = 6; // Magic-Number (length 6) + *(uint32_t *) l = htonl(session[s].magic); + l += 4; + } *(uint16_t *)(q + 2) = htons(l - q); // Length LOG_HEX(5, "PPPLCP", q, l - q); + if (config->debug > 3) dumplcp(q, l - q); + tunnelsend(b, (l - b), t); + restart_timer(s, lcp); } // Send CCP request for no compression -void sendccp(tunnelidt t, sessionidt s) +void sendccp(sessionidt s, tunnelidt t) { uint8_t b[500], *q; - if (!(q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP))) + if (!(q = makeppp(b, sizeof(b), NULL, 0, s, t, PPPCCP))) return; - LOG(4, s, t, "Sending CCP ConfigReq for no compression\n"); + LOG(3, s, t, "CCP: send ConfigReq (no compression)\n"); + *q = ConfigReq; - *(uint8_t *)(q + 1) = (time_now % 255) + 1; // ID + *(q + 1) = ++sess_local[s].lcp_ident; // ID *(uint16_t *)(q + 2) = htons(4); // Length LOG_HEX(5, "PPPCCP", q, 4); tunnelsend(b, (q - b) + 4 , t); + restart_timer(s, ccp); +} + +// Reject unknown/unconfigured protocols +void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto) +{ + + uint8_t buf[MAXETHER]; + uint8_t *q; + int mru = session[s].mru; + if (mru < MINMTU) mru = MINMTU; + if (mru > sizeof(buf)) mru = sizeof(buf); + + l += 6; + if (l > mru) l = mru; + + q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP); + if (!q) return; + + *q = ProtocolRej; + *(q + 1) = ++sess_local[s].lcp_ident; + *(uint16_t *)(q + 2) = htons(l); + *(uint16_t *)(q + 4) = htons(proto); + memcpy(q + 6, p, l - 6); + + if (proto == PPPIPV6CP) + LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n"); + else + LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto); + + tunnelsend(buf, l + (q - buf), t); }