+ if (*p == ConfigAck)
+ {
+ int x = l - 4;
+ uint8_t *o = (p + 4);
+ int authtype = 0;
+
+ while (x > 2)
+ {
+ int type = o[0];
+ int length = o[1];
+
+ if (length == 0 || type == 0 || x < length) break;
+ switch (type)
+ {
+ case 3: // Authentication-Protocol
+ {
+ int proto = ntohs(*(uint16_t *)(o + 2));
+ if (proto == PPPPAP)
+ authtype = AUTHPAP;
+ else if (proto == PPPCHAP && *(o + 4) == 5)
+ authtype = AUTHCHAP;
+ }
+
+ break;
+ }
+ x -= length;
+ o += length;
+ }
+
+ if (!session[s].ip && authtype)
+ sess_local[s].lcp_authtype = authtype;
+
+ switch (session[s].ppp.lcp)
+ {
+ case RequestSent:
+ initialise_restart_count(s, lcp);
+ change_state(s, lcp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "LCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.lcp));
+ if (session[s].ppp.lcp == Opened)
+ lcp_restart(s);
+
+ sendlcp(s, t);
+ change_state(s, lcp, RequestSent);
+ break;
+
+ case AckSent:
+ lcp_open(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ }
+ }
+ else if (*p == ConfigReq)
+ {
+ int x = l - 4;
+ uint8_t *o = (p + 4);
+ uint8_t *response = 0;
+ static uint8_t asyncmap[4] = { 0, 0, 0, 0 }; // all zero
+ static uint8_t authproto[5];
+ int changed = 0;
+
+ while (x > 2)
+ {
+ int type = o[0];
+ int length = o[1];
+
+ if (length == 0 || type == 0 || x < length) break;
+ switch (type)
+ {
+ case 1: // Maximum-Receive-Unit
+ {
+ uint16_t mru = ntohs(*(uint16_t *)(o + 2));
+ if (mru >= MINMTU)
+ {
+ session[s].mru = mru;
+ changed++;
+ 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(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
+ {
+ int proto = ntohs(*(uint16_t *)(o + 2));
+ char proto_name[] = "0x0000";
+ int alen;
+
+ if (proto == PPPPAP)
+ {
+ if (config->radius_authtypes & AUTHPAP)
+ {
+ sess_local[s].lcp_authtype = AUTHPAP;
+ break;
+ }
+
+ strcpy(proto_name, "PAP");
+ }
+ else if (proto == PPPCHAP)
+ {
+ if (config->radius_authtypes & AUTHCHAP
+ && *(o + 4) == 5) // MD5
+ {
+ sess_local[s].lcp_authtype = AUTHCHAP;
+ break;
+ }
+
+ strcpy(proto_name, "CHAP");
+ }
+ else
+ sprintf(proto_name, "%#4.4x", proto);
+
+ 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_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_conf_nak(s, b, sizeof(b), PPPLCP, &response, q, p, o, authproto + 2, alen - 2);
+ }
+
+ break;
+ }
+ break;
+
+ case 4: // Quality-Protocol
+ case 5: // Magic-Number
+ case 7: // Protocol-Field-Compression
+ case 8: // Address-And-Control-Field-Compression
+ break;
+
+ case 17: // Multilink Max-Receive-Reconstructed-Unit
+ {
+ uint16_t mrru = ntohs(*(uint16_t *)(o + 2));
+ session[s].mrru = mrru;
+ changed++;
+ LOG(3, s, t, " Received PPP LCP option MRRU: %d\n",mrru);
+ }
+ break;
+
+ case 18: // Multilink Short Sequence Number Header Format
+ {
+ session[s].mssf = 1;
+ changed++;
+ LOG(3, s, t, " Received PPP LCP option MSSN format\n");
+ }
+ break;
+
+ case 19: // Multilink Endpoint Discriminator
+ {
+ uint8_t epdis_class = o[2];
+ int addr;
+
+ session[s].epdis.addr_class = epdis_class;
+ session[s].epdis.length = length - 3;
+ if (session[s].epdis.length > 20)
+ {
+ LOG(1, s, t, "Error: received EndDis Address Length more than 20: %d\n", session[s].epdis.length);
+ session[s].epdis.length = 20;
+ }
+
+ for (addr = 0; addr < session[s].epdis.length; addr++)
+ session[s].epdis.address[addr] = o[3+addr];
+
+ changed++;
+
+ switch (epdis_class)
+ {
+ case LOCALADDR:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis Local Address Class: %d\n",epdis_class);
+ break;
+ case IPADDR:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis IP Address Class: %d\n",epdis_class);
+ break;
+ case IEEEMACADDR:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis IEEE MAC Address Class: %d\n",epdis_class);
+ break;
+ case PPPMAGIC:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis PPP Magic No Class: %d\n",epdis_class);
+ break;
+ case PSNDN:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis PSND No Class: %d\n",epdis_class);
+ break;
+ default:
+ LOG(3, s, t, " Received PPP LCP option Multilink EndDis NULL Class %d\n",epdis_class);
+ }
+ }
+ break;
+
+ default: // Reject any unknown options
+ 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;
+ }
+
+ if (changed)
+ cluster_send_session(s);
+
+ if (response)
+ {
+ l = q - response; // LCP packet length
+ *((uint16_t *) (response + 2)) = htons(l); // update header
+ }
+ else
+ {
+ // Send packet back as ConfigAck
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
+ if (!response) return;
+ *response = ConfigAck;
+ }
+
+ switch (session[s].ppp.lcp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
+
+ case Stopped:
+ initialise_restart_count(s, lcp);
+ sendlcp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+ else
+ change_state(s, lcp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ lcp_open(s, t);
+
+ break;
+
+ case Opened:
+ lcp_restart(s);
+ sendlcp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, lcp, AckSent);
+ else
+ change_state(s, lcp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ return;
+ }
+
+ 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 || *p == ConfigRej)
+ {
+ int x = l - 4;
+ uint8_t *o = (p + 4);
+ int authtype = -1;
+
+ while (x > 2)
+ {
+ int type = o[0];
+ int length = o[1];
+
+ if (length == 0 || type == 0 || x < length) break;
+ switch (type)
+ {
+ case 1: // Maximum-Receive-Unit
+ 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;
+
+ 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 && length > 4 && *(o + 4) == 5)
+ {
+ authtype = config->radius_authtypes & AUTHCHAP;
+ LOG(3, s, t, " Remote requested CHAP authentication...%sing\n",
+ authtype ? "accept" : "reject");
+ }
+ else
+ {
+ LOG(3, s, t, " Rejecting unsupported authentication %#4x\n",
+ proto);
+ }
+ }
+ else
+ {
+ LOG(2, s, t, "LCP: remote rejected auth negotiation\n");
+ authtype = 0; // shutdown
+ }
+
+ break;
+
+ 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;
+
+ case 17: // Multilink Max-Receive-Reconstructed-Unit
+ {
+ if (*p == ConfigNak)
+ {
+ sess_local[s].mp_mrru = ntohs(*(uint16_t *)(o + 2));
+ LOG(3, s, t, " Remote requested MRRU of %u\n", sess_local[s].mp_mrru);
+ }
+ else
+ {
+ sess_local[s].mp_mrru = 0;
+ LOG(3, s, t, " Remote rejected MRRU negotiation\n");
+ }
+ }
+ break;
+
+ case 18: // Multilink Short Sequence Number Header Format
+ {
+ if (*p == ConfigNak)
+ {
+ sess_local[s].mp_mssf = 0;
+ LOG(3, s, t, " Remote requested Naked mssf\n");
+ }
+ else
+ {
+ sess_local[s].mp_mssf = 0;
+ LOG(3, s, t, " Remote rejected mssf\n");
+ }
+ }
+ break;
+
+ case 19: // Multilink Endpoint Discriminator
+ {
+ if (*p == ConfigNak)
+ {
+ LOG(2, s, t, " Remote should not configNak Endpoint Dis!\n");
+ }
+ else
+ {
+ sess_local[s].mp_epdis = 0;
+ LOG(3, s, t, " Remote rejected Endpoint Discriminator\n");
+ }
+ }
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: remote sent %s for type %u?\n", ppp_code(*p), type);
+ sessionshutdown(s, "Unable to negotiate LCP.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+ return;
+ }
+ x -= length;
+ o += length;
+ }
+
+ if (!authtype)
+ {
+ sessionshutdown(s, "Unsupported authentication.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+ return;
+ }
+
+ if (authtype > 0)
+ sess_local[s].lcp_authtype = authtype;
+
+ switch (session[s].ppp.lcp)
+ {
+ case Closed:
+ case Stopped:
+ {
+ uint8_t *response = makeppp(b, sizeof(b), p, 2, s, t, PPPLCP, 0, 0, 0);
+ 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;
+
+ case RequestSent:
+ case AckSent:
+ initialise_restart_count(s, lcp);
+ 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);
+ break;
+
+ case Opened:
+ lcp_restart(s);
+ sendlcp(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ return;
+ }
+ }
+ else if (*p == TerminateReq)
+ {
+ switch (session[s].ppp.lcp)
+ {
+ case Closed:
+ case Stopped:
+ case Closing:
+ case Stopping:
+ case RequestSent:
+ case AckReceived:
+ case AckSent:
+ break;
+
+ case Opened:
+ lcp_restart(s);
+ zero_restart_count(s, lcp);
+ change_state(s, lcp, Closing);
+ break;
+
+ default:
+ LOG(2, s, t, "LCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.lcp));
+ return;
+ }
+
+ *p = TerminateAck; // send ack
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
+ 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
+ }
+ else if (*p == ProtocolRej)
+ {
+ 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(3, s, t, "LCP protocol reject: 0x%04X\n", proto);
+ }
+ }
+ else if (*p == EchoReq)
+ {
+ *p = EchoReply; // reply
+ *(uint32_t *) (p + 4) = htonl(session[s].magic); // our magic number
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPLCP, 0, 0, 0);
+ 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 if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPLCP, "LCP", p, l, b, sizeof(b));
+ }
+}
+
+int join_bundle(sessionidt s)
+{
+ // Search for a bundle to join
+ bundleidt i;
+ bundleidt b;
+ for (i = 1; i < MAXBUNDLE; i++)
+ {
+ if (bundle[i].state != BUNDLEFREE)
+ {
+ if (epdiscmp(session[s].epdis,bundle[i].epdis) && !strcmp(session[s].user, bundle[i].user))
+ {
+ session[s].bundle = i;
+ bundle[i].mrru = session[s].mrru;
+ bundle[i].mssf = session[s].mssf;
+ if (session[s].epdis.length > 0)
+ setepdis(&bundle[i].epdis, session[s].epdis);
+
+ strcpy(bundle[i].user, session[s].user);
+ bundle[i].members[bundle[i].num_of_links] = s;
+ bundle[i].num_of_links++;
+ LOG(3, s, session[s].tunnel, "MPPP: Bundling additional line in bundle (%d), lines:%d\n",i,bundle[i].num_of_links);
+ return i;
+ }
+ }
+ }
+
+ // No previously created bundle was found for this session, so create a new one
+ if (!(b = new_bundle())) return 0;
+
+ session[s].bundle = b;
+ bundle[b].mrru = session[s].mrru;
+ bundle[b].mssf = session[s].mssf;
+ if (session[s].epdis.length > 0)
+ setepdis(&bundle[b].epdis, session[s].epdis);
+
+ strcpy(bundle[b].user, session[s].user);
+ bundle[b].members[0] = s;
+ LOG(3, s, session[s].tunnel, "MPPP: Created a new bundle (%d)\n", b);
+ return b;
+}
+
+static int epdiscmp(epdist ep1, epdist ep2)
+{
+ int ad;
+ if (ep1.length != ep2.length)
+ return 0;
+
+ if (ep1.addr_class != ep2.addr_class)
+ return 0;
+
+ for (ad = 0; ad < ep1.length; ad++)
+ if (ep1.address[ad] != ep2.address[ad])
+ return 0;
+
+ return 1;
+}
+
+static void setepdis(epdist *ep1, epdist ep2)
+{
+ int ad;
+ ep1->length = ep2.length;
+ ep1->addr_class = ep2.addr_class;
+ for (ad = 0; ad < ep2.length; ad++)
+ ep1->address[ad] = ep2.address[ad];
+}
+
+static bundleidt new_bundle()
+{
+ bundleidt i;
+ for (i = 1; i < MAXBUNDLE; i++)
+ {
+ if (bundle[i].state == BUNDLEFREE)
+ {
+ LOG(4, 0, 0, "MPPP: Assigning bundle ID %d\n", i);
+ bundle[i].num_of_links = 1;
+ bundle[i].last_check = time_now; // Initialize last_check value
+ bundle[i].state = BUNDLEOPEN;
+ bundle[i].current_ses = -1; // This is to enforce the first session 0 to be used at first
+ if (i > config->cluster_highest_bundleid)
+ config->cluster_highest_bundleid = i;
+ return i;
+ }
+ }
+ LOG(0, 0, 0, "MPPP: Can't find a free bundle! There shouldn't be this many in use!\n");
+ return 0;
+}
+
+static void ipcp_open(sessionidt s, tunnelidt t)
+{
+ LOG(3, s, t, "IPCP: Opened, session is now active\n");
+
+ change_state(s, ipcp, Opened);
+
+ 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(s, t);
+ change_state(s, ipv6cp, RequestSent);
+ }
+}
+
+// Process IPCP messages
+void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+ uint8_t b[MAXETHER];
+ uint8_t *q = 0;
+ uint16_t hl;
+
+ CSTAT(processipcp);
+
+ LOG_HEX(5, "IPCP", p, l);
+ if (l < 4)
+ {
+ LOG(1, s, t, "Short IPCP %d bytes\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
+ if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
+ {
+ LOG(1, s, t, "Length mismatch IPCP %u/%u\n", hl, l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+ l = hl;
+
+ if (session[s].ppp.phase < Network)
+ {
+ LOG(2, s, t, "IPCP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+ return;
+ }
+
+ LOG(3, s, t, "IPCP: recv %s\n", ppp_code(*p));
+
+ if (*p == ConfigAck)
+ {
+ switch (session[s].ppp.ipcp)
+ {
+ case RequestSent:
+ initialise_restart_count(s, ipcp);
+ change_state(s, ipcp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "IPCP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipcp));
+ sendipcp(s, t);
+ change_state(s, ipcp, RequestSent);
+ break;
+
+ case AckSent:
+ ipcp_open(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+ }
+ }
+ else if (*p == ConfigReq)
+ {
+ uint8_t *response = 0;
+ uint8_t *o = p + 4;
+ int length = l - 4;
+ int gotip = 0;
+ in_addr_t addr;
+
+ while (length > 2)
+ {
+ if (!o[1] || o[1] > length) return;
+
+ switch (*o)
+ {
+ case 3: // ip address
+ gotip++; // seen address
+ if (o[1] != 6) return;
+
+ addr = htonl(session[s].ip);
+ if (memcmp(o + 2, &addr, (sizeof addr)))
+ {
+ 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.", CDN_ADMIN_DISC, TERM_USER_ERROR);
+ return;
+ }
+ }
+
+ break;
+
+ case 129: // primary DNS
+ if (o[1] != 6) return;
+
+ addr = htonl(session[s].dns1);
+ if (memcmp(o + 2, &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) return;
+
+ addr = htonl(session[s].dns2);
+ if (memcmp(o + 2, &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;
+
+ default:
+ LOG(2, s, t, " Rejecting PPP IPCP Option type %d\n", *o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPCP, &response, q, p, o);
+ if (!q) return;
+ }
+
+ length -= o[1];
+ o += o[1];
+ }
+
+ if (response)
+ {
+ l = q - response; // IPCP packet length
+ *((uint16_t *) (response + 2)) = htons(l); // update header
+ }
+ else if (gotip)
+ {
+ // Send packet back as ConfigAck
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
+ if (!response) return;
+ *response = ConfigAck;
+ }
+ else
+ {
+ LOG(1, s, t, "No IP in IPCP request\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+
+ switch (session[s].ppp.ipcp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPCP, 0, 0, 0);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
+
+ case Stopped:
+ initialise_restart_count(s, ipcp);
+ sendipcp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+ else
+ change_state(s, ipcp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ ipcp_open(s, t);
+
+ break;
+
+ case Opened:
+ initialise_restart_count(s, ipcp);
+ sendipcp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, ipcp, AckSent);
+ else
+ change_state(s, ipcp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+ return;
+ }
+
+ LOG(3, s, t, "IPCP: send %s\n", ppp_code(*response));
+ tunnelsend(b, l + (response - b), t);
+ }
+ else if (*p == TerminateReq)
+ {
+ switch (session[s].ppp.ipcp)
+ {
+ case Closed:
+ case Stopped:
+ case Closing:
+ case Stopping:
+ case RequestSent:
+ case AckReceived:
+ case AckSent:
+ break;
+
+ case Opened:
+ zero_restart_count(s, ipcp);
+ change_state(s, ipcp, Closing);
+ break;
+
+ default:
+ LOG(2, s, t, "IPCP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipcp));
+ return;
+ }
+
+ *p = TerminateAck; // send ack
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPIPCP, 0, 0, 0);
+ if (!q) return;
+
+ LOG(3, s, t, "IPCP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t); // send it
+ }
+ else if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPIPCP, "IPCP", p, l, b, sizeof(b));
+ }
+}
+
+static void ipv6cp_open(sessionidt s, tunnelidt t)
+{
+ 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(s, t, NULL);
+}
+
+// Process IPV6CP messages
+void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+ uint8_t b[MAXETHER];
+ uint8_t *q = 0;
+ uint16_t hl;
+
+ CSTAT(processipv6cp);
+
+ LOG_HEX(5, "IPV6CP", p, l);
+ if (l < 4)
+ {
+ LOG(1, s, t, "Short IPV6CP %d bytes\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
+ if ((hl = ntohs(*(uint16_t *) (p + 2))) > l)
+ {
+ LOG(1, s, t, "Length mismatch IPV6CP %u/%u\n", hl, l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+ l = hl;
+
+ if (session[s].ppp.phase < Network)
+ {
+ LOG(2, s, t, "IPV6CP %s ignored in %s phase\n", ppp_code(*p), ppp_phase(session[s].ppp.phase));
+ return;
+ }
+
+ LOG(3, s, t, "IPV6CP: recv %s\n", ppp_code(*p));
+
+ if (!session[s].ip)
+ {
+ LOG(3, s, t, "IPV6CP: no IPv4 address (IPCP in state %s)\n", ppp_state(session[s].ppp.ipcp));
+ return; // need IPCP to complete...
+ }
+
+ if (*p == ConfigAck)
+ {
+ switch (session[s].ppp.ipv6cp)
+ {
+ case RequestSent:
+ initialise_restart_count(s, ipv6cp);
+ change_state(s, ipv6cp, AckReceived);
+ break;
+
+ case AckReceived:
+ case Opened:
+ LOG(2, s, t, "IPV6CP: ConfigAck in state %s? Sending ConfigReq\n", ppp_state(session[s].ppp.ipv6cp));
+ sendipv6cp(s, t);
+ change_state(s, ipv6cp, RequestSent);
+ break;
+
+ case AckSent:
+ ipv6cp_open(s, t);
+ break;
+
+ default:
+ LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+ }
+ }
+ else if (*p == ConfigReq)
+ {
+ uint8_t *response = 0;
+ uint8_t *o = p + 4;
+ int length = l - 4;
+ int gotip = 0;
+ uint8_t ident[8];
+
+ while (length > 2)
+ {
+ if (!o[1] || o[1] > length) return;
+
+ switch (*o)
+ {
+ case 1: // interface identifier
+ gotip++; // seen address
+ 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_conf_nak(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o, ident, sizeof(ident));
+ if (!q) return;
+ }
+
+ break;
+
+ default:
+ LOG(2, s, t, " Rejecting PPP IPV6CP Option type %d\n", *o);
+ q = ppp_conf_rej(s, b, sizeof(b), PPPIPV6CP, &response, q, p, o);
+ if (!q) return;
+ }
+
+ length -= o[1];
+ o += o[1];
+ }
+
+ if (response)
+ {
+ l = q - response; // IPV6CP packet length
+ *((uint16_t *) (response + 2)) = htons(l); // update header
+ }
+ else if (gotip)
+ {
+ // Send packet back as ConfigAck
+ response = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP, 0, 0, 0);
+ if (!response) return;
+ *response = ConfigAck;
+ }
+ else
+ {
+ LOG(1, s, t, "No interface identifier in IPV6CP request\n");
+ STAT(tunnel_rx_errors);
+ return;
+ }
+
+ switch (session[s].ppp.ipv6cp)
+ {
+ case Closed:
+ response = makeppp(b, sizeof(b), p, 2, s, t, PPPIPV6CP, 0, 0, 0);
+ if (!response) return;
+ *response = TerminateAck;
+ *((uint16_t *) (response + 2)) = htons(l = 4);
+ break;
+
+ case Stopped:
+ initialise_restart_count(s, ipv6cp);
+ sendipv6cp(s, t);
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+ else
+ change_state(s, ipv6cp, RequestSent);
+
+ break;
+
+ case RequestSent:
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+
+ break;
+
+ case AckReceived:
+ if (*response == ConfigAck)
+ ipv6cp_open(s, t);
+
+ break;
+
+ case Opened:
+ initialise_restart_count(s, ipv6cp);
+ sendipv6cp(s, t);
+ /* fallthrough */
+
+ case AckSent:
+ if (*response == ConfigAck)
+ change_state(s, ipv6cp, AckSent);
+ else
+ change_state(s, ipv6cp, RequestSent);
+
+ break;
+
+ default:
+ LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+ return;
+ }
+
+ LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*response));
+ tunnelsend(b, l + (response - b), t);
+ }
+ else if (*p == TerminateReq)
+ {
+ switch (session[s].ppp.ipv6cp)
+ {
+ case Closed:
+ case Stopped:
+ case Closing:
+ case Stopping:
+ case RequestSent:
+ case AckReceived:
+ case AckSent:
+ break;
+
+ case Opened:
+ zero_restart_count(s, ipv6cp);
+ change_state(s, ipv6cp, Closing);
+ break;
+
+ default:
+ LOG(2, s, t, "IPV6CP: ignoring %s in state %s\n", ppp_code(*p), ppp_state(session[s].ppp.ipv6cp));
+ return;
+ }
+
+ *p = TerminateAck; // send ack
+ q = makeppp(b, sizeof(b), p, l, s, t, PPPIPV6CP, 0, 0, 0);
+ if (!q) return;
+
+ LOG(3, s, t, "IPV6CP: send %s\n", ppp_code(*q));
+ tunnelsend(b, l + (q - b), t); // send it
+ }
+ else if (*p != CodeRej)
+ {
+ ppp_code_rej(s, t, PPPIPV6CP, "IPV6CP", p, l, b, sizeof(b));
+ }
+}
+
+// process IP packet received
+//
+// This MUST be called with at least 4 byte behind 'p'.
+// (i.e. this routine writes to p[-4]).
+void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
+{
+ in_addr_t ip;
+
+ CSTAT(processipin);
+
+ 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)
+ {
+ LOG(1, s, t, "IP packet too long %d\n", l);
+ STAT(tunnel_rx_errors);
+ return ;
+ }
+
+ if (session[s].ppp.phase != Network || session[s].ppp.ipcp != Opened)
+ return;
+
+ if (!session[s].bundle || bundle[session[s].bundle].num_of_links < 2) // FIXME:
+ {
+ // no spoof (do sessionbyip to handled statically routed subnets)
+ if (ip != session[s].ip && sessionbyip(htonl(ip)) != s)
+ {
+ LOG(4, s, t, "Dropping packet with spoofed IP %s\n", fmtaddr(htonl(ip), 0));
+ return;
+ }
+ }
+
+ // run access-list if any
+ 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);
+ l += 4;
+
+ // Are we throttled and a slave?
+ if (session[s].tbf_in && !config->cluster_iam_master) {
+ // Pass it to the master for handling.
+ master_throttle_packet(session[s].tbf_in, p, l);
+ return;
+ }
+
+ // Are we throttled and a master??
+ if (session[s].tbf_in && config->cluster_iam_master) {
+ // Actually handle the throttled packets.
+ tbf_queue_packet(session[s].tbf_in, p, l);
+ return;
+ }
+
+ // send to ethernet
+ if (tun_write(p, l) < 0)
+ {
+ STAT(tun_tx_errors);
+ LOG(0, s, t, "Error writing %d bytes to TUN device: %s (tunfd=%d, p=%p)\n",
+ l, strerror(errno), tunfd, p);
+
+ return;
+ }
+
+ p += 4;
+ l -= 4;
+
+ if (session[s].snoop_ip && session[s].snoop_port)
projects / l2tpns.git / blobdiff