X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/570d0d53855b9121b29c94bd20206e2158130997..bf78c77b229b28a7f614c023e0f03bb317317e84:/ppp.c diff --git a/ppp.c b/ppp.c index a88add9..f84386c 100644 --- a/ppp.c +++ b/ppp.c @@ -1,6 +1,6 @@ // L2TPNS PPP Stuff -char const *cvs_id_ppp = "$Id: ppp.c,v 1.7 2004/07/08 16:54:35 bodea Exp $"; +char const *cvs_id_ppp = "$Id: ppp.c,v 1.15 2004/09/19 23:19:23 fred_nerk Exp $"; #include #include @@ -23,6 +23,8 @@ extern u32 eth_tx; extern time_t time_now; extern struct configt *config; +void sendccp(tunnelidt t, sessionidt s); + // Process PAP messages void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l) { @@ -74,25 +76,27 @@ void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l) return; } if (session[s].ip) - *p = 2; // ACK + *p = 2; // ACK else - *p = 3; // cant authorise + *p = 3; // cant authorise p[1] = id; - *(u16 *) (p + 2) = htons(5); // length - p[4] = 0; // no message + *(u16 *) (p + 2) = htons(5); // length + p[4] = 0; // no message if (session[s].ip) { - log(3, session[s].ip, s, t, "%d Already an IP allocated: %s (%d)\n", getpid(), inet_toa(htonl(session[s].ip)), session[s].ip_pool_index); + log(3, session[s].ip, s, t, "%d Already an IP allocated: %s (%d)\n", getpid(), inet_toa(htonl(session[s].ip)), session[s].ip_pool_index); + session[s].flags &= ~SF_IPCP_ACKED; } else { - log(1, 0, s, t, "No radius session available to authenticate session...\n"); + log(1, 0, s, t, "No radius session available to authenticate session...\n"); } log(3, 0, s, t, "Fallback response to PAP (%s)\n", (session[s].ip) ? "ACK" : "NAK"); tunnelsend(b, 5 + (p - b), t); // send it } else - { // set up RADIUS request + { + // set up RADIUS request u16 r = session[s].radius; // Run PRE_AUTH plugins @@ -213,6 +217,7 @@ char *ppp_lcp_types[] = { "EchoReq", "EchoReply", "DiscardRequest", + "IdentRequest", }; void dumplcp(u8 *p, int l) @@ -230,9 +235,9 @@ void dumplcp(u8 *p, int l) { int type = o[0]; int length = o[1]; - if (length == 0) + if (length < 2) { - log(4, 0, 0, 0, " Option length is 0...\n"); + log(4, 0, 0, 0, " Option length is %d...\n", length); break; } if (type == 0) @@ -245,13 +250,22 @@ void dumplcp(u8 *p, int l) switch (type) { case 1: // Maximum-Receive-Unit - log(4, 0, 0, 0, " %s %d\n", lcp_types[type], ntohs(*(u16 *)(o + 2))); + if (length == 4) + log(4, 0, 0, 0, " %s %d\n", lcp_types[type], ntohs(*(u16 *)(o + 2))); + else + log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length); break; case 3: // Authentication-Protocol { - int proto = ntohs(*(u16 *)(o + 2)); - log(4, 0, 0, 0, " %s %s\n", lcp_types[type], - proto == 0xC223 ? "CHAP" : "PAP"); + if (length == 4) + { + int proto = ntohs(*(u16 *)(o + 2)); + log(4, 0, 0, 0, " %s 0x%x (%s)\n", lcp_types[type], proto, + proto == 0xC223 ? "CHAP" : + proto == 0xC023 ? "PAP" : "UNKNOWN"); + } + else + log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length); break; } case 4: // Quality-Protocol @@ -262,20 +276,23 @@ void dumplcp(u8 *p, int l) } case 5: // Magic-Number { - u32 magicno = ntohl(*(u32 *)(o + 2)); - log(4, 0, 0, 0, " %s %x\n", lcp_types[type], magicno); + if (length == 6) + { + u32 magicno = ntohl(*(u32 *)(o + 2)); + log(4, 0, 0, 0, " %s %x\n", lcp_types[type], magicno); + } + else + log(4, 0, 0, 0, " %s odd length %d\n", lcp_types[type], length); break; } case 7: // Protocol-Field-Compression { - u32 pfc = ntohl(*(u32 *)(o + 2)); - log(4, 0, 0, 0, " %s %x\n", lcp_types[type], pfc); + log(4, 0, 0, 0, " %s\n", lcp_types[type]); break; } case 8: // Address-And-Control-Field-Compression { - u32 afc = ntohl(*(u32 *)(o + 2)); - log(4, 0, 0, 0, " %s %x\n", lcp_types[type], afc); + log(4, 0, 0, 0, " %s\n", lcp_types[type]); break; } default: @@ -292,6 +309,7 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) { u8 b[MAXCONTROL]; u8 *q = NULL; + u32 magicno = 0; CSTAT(call_processlcp); @@ -306,6 +324,7 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) if (*p == ConfigAck) { log(3, session[s].ip, s, t, "LCP: Discarding ConfigAck\n"); + session[s].flags |= SESSIONLCPACK; } else if (*p == ConfigReq) { @@ -325,6 +344,10 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) case 1: // Maximum-Receive-Unit session[s].mru = ntohs(*(u16 *)(o + 2)); break; + case 2: // asyncmap + log_hex(2, "PPP LCP Packet", p, l); + log(2, 0, 0, 0, "PPP LCP Packet type %d (%s len %d)\n", *p, ppp_lcp_types[(int)*p], ntohs( ((u16 *) p)[1]) ); + break; case 3: // Authentication-Protocol { int proto = ntohs(*(u16 *)(o + 2)); @@ -349,27 +372,36 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) } case 5: // Magic-Number { -// u32 magicno = ntohl(*(u32 *)(o + 2)); + magicno = ntohl(*(u32 *)(o + 2)); break; } case 4: // Quality-Protocol - { -// u32 qp = ntohl(*(u32 *)(o + 2)); - break; - } case 7: // Protocol-Field-Compression - { -// u32 pfc = ntohl(*(u32 *)(o + 2)); - break; - } case 8: // Address-And-Control-Field-Compression - { -// u32 afc = ntohl(*(u32 *)(o + 2)); break; + case 13: // CallBack option for LCP extention of win2000/routers L2TP client + case 17: + case 18: + { + // Reject LCP CallBack + log(2, session[s].ip, s, t, " PPP LCP Option type %d, len=%d\n", type, length); + memcpy(p + 4, o, length); + *(u16 *)(p + 2) = htons(length + 4); + *p = ConfigRej; + q = makeppp(b,sizeof(b), p, length + 4, t, s, PPPLCP); + tunnelsend(b, 12 + length + 4, t); + return; } + default: + // Reject Unknown LCP Option to stop to send it again log(2, session[s].ip, s, t, " Unknown PPP LCP Option type %d\n", type); - break; + memcpy(p + 4, o, length); + *(u16 *)(p + 2) = htons(length + 4); + *p = ConfigRej; + q = makeppp(b,sizeof(b), p, length + 4, t, s, PPPLCP); + tunnelsend(b, 12 + length + 4, t); + return; } x -= length; o += length; @@ -379,8 +411,11 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) { // Send back a ConfigAck log(3, session[s].ip, s, t, "ConfigReq accepted, sending as Ack\n"); + // for win2k L2TP clientis and LCP renegotiation of alive session + if (magicno || l == 4) initlcp(t, s); q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); - if (!q) { + if (!q) + { log(3, session[s].ip, s, t, " failed to create packet.\n"); return; } @@ -392,15 +427,10 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) // Already built a ConfigNak... send it log(3, session[s].ip, s, t, "Sending ConfigNak\n"); tunnelsend(b, l + (q - b), t); - - log(3, session[s].ip, s, t, "Sending ConfigReq, requesting PAP login\n"); - q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPLCP); - *q++ = ConfigReq; - *(u8 *)(q++) = 3; - *(u8 *)(q++) = 4; - *(u16 *)(q += 2) = htons(0xC023); - tunnelsend(b, l + (q - b), t); } + + if (!(session[s].flags & SESSIONLCPACK)) + initlcp(t, s); } else if (*p == ConfigNak) { @@ -410,7 +440,7 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) } else if (*p == TerminateReq) { - *p = TerminateAck; // close + *p = TerminateAck; // close q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); if (!q) { log(3, session[s].ip, s, t, "Failed to create PPP packet in processlcp.\n"); @@ -420,13 +450,13 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) sessionshutdown(s, "Remote end closed connection."); tunnelsend(b, l + (q - b), t); // send it } - else if (*p == TerminateReq) + else if (*p == TerminateAck) { - sessionshutdown(s, "Remote end closed connection."); + sessionshutdown(s, "Connection closed."); } else if (*p == EchoReq) { - *p = EchoReply; // reply + *p = EchoReply; // reply *(u32 *) (p + 4) = htonl(session[s].magic); // our magic number q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); if (!q) { @@ -440,6 +470,23 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) { // Ignore it, last_packet time is set earlier than this. } + else if (*p == IdentRequest) + { + *p = CodeRej; + if (l > MAXCONTROL) + { + log(1, 0, s, t, "Truncated Ident Packet (length=%d) to 1400 bytes\n", l); + l = 1400; + } + q = makeppp(b, sizeof(b), p, l, t, s, PPPLCP); + if (!q) + { + log(3, session[s].ip, s, t, "Failed to create IdentRej.\n"); + return; + } + log_hex(5, "LCPIdentRej", q, l + 4); + tunnelsend(b, 12 + 4 + l, t); + } else { log(1, session[s].ip, s, t, "Unexpected LCP code %d\n", *p); @@ -462,9 +509,11 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) return ; } if (*p == ConfigAck) - { // happy with our IPCP + { + // happy with our IPCP u16 r = session[s].radius; - if ((!r || radius[r].state == RADIUSIPCP) && !session[s].walled_garden) { + if ((!r || radius[r].state == RADIUSIPCP) && !session[s].walled_garden) + { if (!r) r = radiusnew(s); if (r) @@ -472,7 +521,8 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) } session[s].flags |= SF_IPCP_ACKED; - return ; // done + log(3, session[s].ip, s, t, "IPCP Acked, session is now active\n"); + return; } if (*p != ConfigReq) { @@ -480,6 +530,7 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) STAT(tunnel_rx_errors); return ; } + log(4, session[s].ip, s, t, "IPCP ConfigReq received\n"); if (ntohs(*(u16 *) (p + 2)) > l) { log(1, 0, s, t, "Length mismatch IPCP %d/%d\n", ntohs(*(u16 *) (p + 2)), l); @@ -489,7 +540,7 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) if (!session[s].ip) { log(3, 0, s, t, "Waiting on radius reply\n"); - return ; // have to wait on RADIUS reply + return; // have to wait on RADIUS reply } // form a config reply quoting the IP in the session { @@ -497,6 +548,7 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) u8 *i, *q; + l = ntohs(*(u16 *) (p + 2)); // We must use length from IPCP len field q = p + 4; i = p + l; while (q < i && q[1]) @@ -506,12 +558,13 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) q += q[1]; } if (q < i) - { // reject + { + // reject u16 n = 4; i = p + l; - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP); - if (!q) { - log(2, 0, s, t, "Failed to send IPCP.\n"); + if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP))) + { + log(2, 0, s, t, "Failed to send IPCP ConfigRej\n"); return; } *q = ConfigRej; @@ -527,30 +580,32 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) p += p[1]; } *(u16 *) (q + 2) = htons(n); + log(4, session[s].ip, s, t, "Sending ConfigRej\n"); tunnelsend(b, n + (q - b), t); // send it } else { + log(4, session[s].ip, s, t, "Sending ConfigAck\n"); *p = ConfigAck; - i = findppp(p, 0x81); // Primary DNS address - if (i) + if ((i = findppp(p, 0x81))) // Primary DNS address { if (*(u32 *) (i + 2) != htonl(session[s].dns1)) { *(u32 *) (i + 2) = htonl(session[s].dns1); *p = ConfigNak; + log(5, session[s].ip, s, t, " DNS1 = %s\n", inet_toa(session[s].dns1)); } } - i = findppp(p, 0x83); // Secondary DNS address (TBA, is it) - if (i) + if ((i = findppp(p, 0x83))) // Secondary DNS address (TBA, is it) { if (*(u32 *) (i + 2) != htonl(session[s].dns2)) { *(u32 *) (i + 2) = htonl(session[s].dns2); *p = ConfigNak; + log(5, session[s].ip, s, t, " DNS2 = %s\n", inet_toa(session[s].dns1)); } } - i = findppp(p, 3); // IP address + i = findppp(p, 3); // IP address if (!i || i[1] != 6) { log(1, 0, s, t, "No IP in IPCP request\n"); @@ -561,9 +616,11 @@ void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l) { *(u32 *) (i + 2) = htonl(session[s].ip); *p = ConfigNak; + log(4, session[s].ip, s, t, " No, a ConfigNak, client is requesting IP - sending %s\n", + inet_toa(htonl(session[s].ip))); } - q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP); - if (!q) { + if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPIPCP))) + { log(2, 0, s, t, " Failed to send IPCP packet.\n"); return; } @@ -580,7 +637,6 @@ void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l) { ipt ip; - CSTAT(call_processipin); log_hex(5, "IP", p, l); @@ -620,7 +676,7 @@ void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l) if (session[s].snoop_ip && session[s].snoop_port) { - // Snooping this session, send it to ASIO + // Snooping this session snoop_send_packet(p, l, session[s].snoop_ip, session[s].snoop_port); } STAT(tun_tx_packets); @@ -690,13 +746,14 @@ void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l) } else { - *p = ConfigRej; // reject + *p = ConfigRej; // reject + sendccp(t, s); } } else - *p = TerminateAck; // close - q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP); - if (!q) { + *p = TerminateAck; // close + if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP))) + { log(1,0,0,0, "Failed to send CCP packet.\n"); return; } @@ -720,12 +777,13 @@ void sendchap(tunnelidt t, sessionidt s) return ; } log(1, 0, s, t, "Send CHAP challenge\n"); - { // new challenge + { + // new challenge int n; for (n = 0; n < 15; n++) radius[r].auth[n] = rand(); } - radius[r].chap = 1; // CHAP not PAP + radius[r].chap = 1; // CHAP not PAP radius[r].id++; if (radius[r].state != RADIUSCHAP) radius[r].try = 0; @@ -742,11 +800,11 @@ void sendchap(tunnelidt t, sessionidt s) log(1, 0, s, t, "failed to send CHAP challenge.\n"); return; } - *q = 1; // challenhe - q[1] = radius[r].id; // ID - q[4] = 16; // length - memcpy(q + 5, radius[r].auth, 16); // challenge - strcpy(q + 21, hostname); // our name + *q = 1; // challenge + q[1] = radius[r].id; // ID + q[4] = 16; // length + memcpy(q + 5, radius[r].auth, 16); // challenge + strcpy(q + 21, hostname); // our name *(u16 *) (q + 2) = htons(strlen(hostname) + 21); // length tunnelsend(b, strlen(hostname) + 21 + (q - b), t); // send it } @@ -756,7 +814,6 @@ void sendchap(tunnelidt t, sessionidt s) // returns start of PPP frame u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype) { - if (size < 12) return NULL; // Need more space than this!! @@ -764,7 +821,7 @@ u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtyp *(u16 *) (b + 2) = htons(tunnel[t].far); // tunnel *(u16 *) (b + 4) = htons(session[s].far); // session b += 6; - if (mtype != PPPLCP && !(session[s].l2tp_flags & SESSIONACFC)) + if (mtype && !(session[s].l2tp_flags & SESSIONACFC)) { *(u16 *) b = htons(0xFF03); // HDLC header b += 2; @@ -797,7 +854,7 @@ u8 *findppp(u8 * b, u8 mtype) while (l) { if (l < b[1] || !b[1]) - return 0; // faulty + return 0; // faulty if (*b == mtype) return b; l -= b[1]; @@ -819,10 +876,26 @@ void initlcp(tunnelidt t, sessionidt s) log(4, 0, s, t, "Sending LCP ConfigReq for PAP\n"); *q = ConfigReq; *(u8 *)(q + 1) = (time_now % 255) + 1; // ID - *(u16 *)(q + 2) = htons(8); // Length - *(u8 *)(q + 4) = 3; - *(u8 *)(q + 5) = 4; - *(u16 *)(q + 6) = htons(0xC023); // PAP - tunnelsend(b, 12 + 8, t); + *(u16 *)(q + 2) = htons(14); // Length + *(u8 *)(q + 4) = 5; + *(u8 *)(q + 5) = 6; + *(u32 *)(q + 6) = htonl(session[s].magic); + *(u8 *)(q + 10) = 3; + *(u8 *)(q + 11) = 4; + *(u16 *)(q + 12) = htons(0xC023); // PAP + tunnelsend(b, 12 + 14, t); +} + +// Send CCP reply +void sendccp(tunnelidt t, sessionidt s) +{ + char *q, b[500] = {0}; + + q = makeppp(b, sizeof(b), NULL, 0, t, s, PPPCCP); + *q = ConfigReq; + *(u8 *)(q + 1) = (time_now % 255) + 1; // ID + *(u16 *)(q + 2) = htons(4); // Length + log_hex(5, "PPPCCP", q, 4); + tunnelsend(b, (q - b) + 4 , t); }