From 6e3d21bbdc2e1cbf4627bd2c6c9f9cbeb19bf9c7 Mon Sep 17 00:00:00 2001 From: fred_nerk Date: Mon, 2 Aug 2004 05:40:21 +0000 Subject: [PATCH] - Add support for LCP Ident and CallBack (rejection only) from Yuri - Initiate LCP if not attempted by the client --- Changes | 2 + l2tpns.c | 8 ++-- l2tpns.h | 5 ++- ppp.c | 116 +++++++++++++++++++++++++++++++++++++++++-------------- 4 files changed, 98 insertions(+), 33 deletions(-) diff --git a/Changes b/Changes index 95bcd81..8b34949 100644 --- a/Changes +++ b/Changes @@ -9,6 +9,8 @@ - Write pid file if filename is set - Add startup script and monitor script from Yuri - Some logging correctness fixes from Iain Wade +- Add support for LCP Ident and CallBack (rejection only) from Yuri +- Initiate LCP if not attempted by the client * Tue Jul 13 2004 Brendan O'Dea 2.0.1 - Update INSTALL, Docs/manual.html documentation. diff --git a/l2tpns.c b/l2tpns.c index f27c7c2..8571762 100644 --- a/l2tpns.c +++ b/l2tpns.c @@ -4,7 +4,7 @@ // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced // vim: sw=8 ts=8 -char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.19 2004/08/02 03:38:01 fred_nerk Exp $"; +char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.20 2004/08/02 05:40:21 fred_nerk Exp $"; #include #include @@ -2035,7 +2035,7 @@ int regular_cleanups(void) if (!session[s].tunnel) // Session isn't in use continue; - if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED) ) + if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED)) { // IPCP has not completed yet. Resend log(3, session[s].ip, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n"); @@ -3497,7 +3497,9 @@ int sessionsetup(tunnelidt t, sessionidt s) for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++) routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1); - if (!session[s].sid) { // did this session just finish radius? + if (!session[s].sid) + { + // did this session just finish radius? log(3, session[s].ip, s, t, "Sending initial IPCP to client\n"); sendipcp(t, s); session[s].sid = ++last_sid; diff --git a/l2tpns.h b/l2tpns.h index 3cae8de..83b0e8b 100644 --- a/l2tpns.h +++ b/l2tpns.h @@ -1,5 +1,5 @@ // L2TPNS Global Stuff -// $Id: l2tpns.h,v 1.14 2004/08/02 03:38:01 fred_nerk Exp $ +// $Id: l2tpns.h,v 1.15 2004/08/02 05:40:21 fred_nerk Exp $ #ifndef __L2TPNS_H__ #define __L2TPNS_H__ @@ -90,7 +90,8 @@ enum ProtocolRej, EchoReq, EchoReply, - DiscardRequest + DiscardRequest, + IdentRequest }; // Types diff --git a/ppp.c b/ppp.c index 3287f3d..af3de1d 100644 --- a/ppp.c +++ b/ppp.c @@ -1,6 +1,6 @@ // L2TPNS PPP Stuff -char const *cvs_id_ppp = "$Id: ppp.c,v 1.9 2004/08/02 03:38:01 fred_nerk Exp $"; +char const *cvs_id_ppp = "$Id: ppp.c,v 1.10 2004/08/02 05:40:21 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) { @@ -83,6 +85,7 @@ void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l) 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); + session[s].flags &= ~SF_IPCP_ACKED; } else { @@ -213,6 +216,7 @@ char *ppp_lcp_types[] = { "EchoReq", "EchoReply", "DiscardRequest", + "IdentRequest", }; void dumplcp(u8 *p, int l) @@ -304,6 +308,7 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) { u8 b[MAXCONTROL]; u8 *q = NULL; + u32 magicno = 0; CSTAT(call_processlcp); @@ -338,6 +343,10 @@ 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)); @@ -362,27 +371,36 @@ 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; @@ -399,6 +417,8 @@ void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l) } *q = ConfigAck; tunnelsend(b, l + (q - b), t); + // For win2k L2TP clients, LCP should be initiated by the LNS + if (magicno) initlcp(t, s); } else { @@ -448,6 +468,23 @@ 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); @@ -470,7 +507,8 @@ 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) @@ -480,7 +518,8 @@ 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) { @@ -488,6 +527,7 @@ 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); @@ -505,6 +545,7 @@ 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]) @@ -514,12 +555,13 @@ 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; @@ -535,27 +577,29 @@ 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 @@ -569,9 +613,11 @@ 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(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; } @@ -699,12 +745,13 @@ void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l) else { *p = ConfigRej; // reject + sendccp(t, s); } } else *p = TerminateAck; // close - q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP); - if (!q) { + if (!(q = makeppp(b, sizeof(b), p, l, t, s, PPPCCP))) + { log(1,0,0,0, "Failed to send CCP packet.\n"); return; } @@ -772,7 +819,7 @@ 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; @@ -834,3 +881,16 @@ void initlcp(tunnelidt t, sessionidt s) tunnelsend(b, 12 + 8, 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); +} + -- 2.20.1