int msg_parse_header(sip_msg_t *msg, const char *header) { struct tm when = { 0 }; char time[20], ipfrom[22], ipto[22]; time_t timet; // Sanity check if (!msg || !header) return 1; if (sscanf(header, "U %d/%d/%d %d:%d:%d.%d %s -> %s", &when.tm_year, &when.tm_mon, &when.tm_mday, &when.tm_hour, &when.tm_min, &when.tm_sec, (int*) &msg->ts.tv_usec, ipfrom, ipto)) { // Fix some time data when.tm_isdst = 1; // Daylight saving time flag when.tm_year -= 1900; // C99 Years since 1900 when.tm_mon--; // C99 0-11 timet = mktime(&when); msg->ts.tv_sec = (long int) timet; // Convert to string strftime(time, 20, "%H:%M:%S", localtime(&timet)); sprintf(time, "%s.%06d", time, (int) msg->ts.tv_usec); msg_set_attribute(msg, SIP_ATTR_TIME, time); msg_set_attribute(msg, SIP_ATTR_SRC, ipfrom); msg_set_attribute(msg, SIP_ATTR_DST, ipto); return 0; } return 1; }
int msg_parse_payload(sip_msg_t *msg, const char *payload) { char *body = strdup(payload); char * pch; char value[256]; char rest[256]; int irest; // Sanity check if (!msg || !payload) return 1; for (pch = strtok(body, "\n"); pch; pch = strtok(NULL, "\n")) { // fix last ngrep line character if (pch[strlen(pch) - 1] == '.') pch[strlen(pch) - 1] = '\0'; // Copy the payload line by line (easier to process by the UI) msg->payload[msg->plines++] = strdup(pch); if (!strlen(pch)) continue; if (sscanf(pch, "X-Call-ID: %[^@\t\n\r]", value) == 1) { msg_set_attribute(msg, SIP_ATTR_XCALLID, value); continue; } if (sscanf(pch, "X-CID: %[^@\t\n\r]", value) == 1) { msg_set_attribute(msg, SIP_ATTR_XCALLID, value); continue; } if (sscanf(pch, "SIP/2.0 %[^\t\n\r]", value)) { if (!msg_get_attribute(msg, SIP_ATTR_METHOD)) { msg_set_attribute(msg, SIP_ATTR_METHOD, value); } continue; } if (sscanf(pch, "CSeq: %d %[^\t\n\r]", &irest, value)) { if (!msg_get_attribute(msg, SIP_ATTR_METHOD)) { // ACK Messages are not considered requests if (strcasecmp(value, "ACK")) msg_set_attribute(msg, SIP_ATTR_REQUEST, "1"); msg_set_attribute(msg, SIP_ATTR_METHOD, value); } continue; } if (sscanf(pch, "From: %[^:]:%[^\t\n\r>;]", rest, value)) { msg_set_attribute(msg, SIP_ATTR_SIPFROM, value); continue; } if (sscanf(pch, "To: %[^:]:%[^\t\n\r>;]", rest, value)) { msg_set_attribute(msg, SIP_ATTR_SIPTO, value); continue; } if (!strncasecmp(pch, "Content-Type: application/sdp", 29)) { sprintf(value, "%s (SDP)", msg_get_attribute(msg, SIP_ATTR_METHOD)); msg_set_attribute(msg, SIP_ATTR_METHOD, value); continue; } } free(body); return 0; }
sip_msg_t * sip_load_message(const char *header, const char *payload) { sip_msg_t *msg; sip_call_t *call; char *callid; // Get the Call-ID of this message if (!(callid = sip_get_callid(payload))) { return NULL; } // Create a new message from this data if (!(msg = sip_msg_create(header, payload))) { return NULL; } // Find the call for this msg if (!(call = call_find_by_callid(callid))) { // Create the call if not found if (!(call = sip_call_create(callid))) { //@todo sip_msg_destroy(); return NULL; } } // Set message callid msg_set_attribute(msg, SIP_ATTR_CALLID, callid); // Add the message to the found/created call call_add_message(call, msg); // Return the loaded message return msg; }
void parse_packet(u_char *mode, const struct pcap_pkthdr *header, const u_char *packet) { // Datalink Header size int size_link; // IP version uint32_t ip_ver; // IP header data struct ip *ip4; #ifdef WITH_IPV6 // IPv6 header data struct ip6_hdr *ip6; #endif // IP protocol uint8_t ip_proto; // IP segment length uint32_t ip_len; // IP header size uint32_t size_ip; // Fragment offset uint16_t ip_off = 0; // Fragmentation flag uint8_t ip_frag = 0; // Fragmentation offset uint16_t ip_frag_off = 0; //! Source Address char ip_src[INET6_ADDRSTRLEN + 1]; //! Destination Address char ip_dst[INET6_ADDRSTRLEN + 1]; // UDP header data struct udphdr *udp; // UDP header size uint16_t udp_size; // TCP header data struct tcphdr *tcp; // TCP header size uint16_t tcp_size; // Packet payload data u_char *msg_payload = NULL; // Packet payload size uint32_t size_payload; // Parsed message data sip_msg_t *msg; // Total packet size uint32_t size_packet; // SIP message transport int transport; /* 0 UDP, 1 TCP, 2 TLS */ // Source and Destination Ports u_short sport, dport; // Ignore packets while capture is paused if (capture_is_paused()) return; // Check if we have reached capture limit if (capinfo.limit && sip_calls_count() >= capinfo.limit) return; // Get link header size from datalink type size_link = datalink_size(capinfo.link); // Get IP header ip4 = (struct ip*) (packet + size_link); #ifdef WITH_IPV6 // Get IPv6 header ip6 = (struct ip6_hdr*)(packet + size_link); #endif // Get IP version ip_ver = ip4->ip_v; switch(ip_ver) { case 4: size_ip = ip4->ip_hl * 4; ip_proto = ip4->ip_p; ip_len = ntohs(ip4->ip_len); inet_ntop(AF_INET, &ip4->ip_src, ip_src, sizeof(ip_src)); inet_ntop(AF_INET, &ip4->ip_dst, ip_dst, sizeof(ip_dst)); ip_off = ntohs(ip4->ip_off); ip_frag = ip_off & (IP_MF | IP_OFFMASK); ip_frag_off = (ip_frag) ? (ip_off & IP_OFFMASK) * 8 : 0; break; #ifdef WITH_IPV6 case 6: size_ip = sizeof(struct ip6_hdr); ip_proto = ip6->ip6_nxt; ip_len = ntohs(ip6->ip6_plen); inet_ntop(AF_INET6, &ip6->ip6_src, ip_src, INET6_ADDRSTRLEN); inet_ntop(AF_INET6, &ip6->ip6_dst, ip_dst, INET6_ADDRSTRLEN); if (ip_proto == IPPROTO_FRAGMENT) { struct ip6_frag *ip6f = (struct ip6_frag *) (ip6 + ip_len); ip_frag_off = ntohs(ip6f->ip6f_offlg & IP6F_OFF_MASK); } break; #endif default: return; } // Only interested in UDP packets if (ip_proto == IPPROTO_UDP) { // Set transport UDP transport = 0; // Get UDP header udp = (struct udphdr*) (packet + size_link + size_ip); udp_size = (ip_frag_off) ? 0 : sizeof(struct udphdr); // Set packet ports sport = udp->uh_sport; dport = udp->uh_dport; size_payload = htons(udp->uh_ulen) - udp_size; if ((int32_t)size_payload > 0 ) { // Get packet payload msg_payload = malloc(size_payload + 1); memset(msg_payload, 0, size_payload + 1); memcpy(msg_payload, (u_char *) (packet + size_link + size_ip + udp_size), size_payload); } // Total packet size size_packet = size_link + size_ip + udp_size + size_payload; } else if (ip_proto == IPPROTO_TCP) { // Set transport TCP transport = 1; tcp = (struct tcphdr*) (packet + size_link + size_ip); tcp_size = (ip_frag_off) ? 0 : (tcp->th_off * 4); // Set packet ports sport = tcp->th_sport; dport = tcp->th_dport; // We're only interested in packets with payload size_payload = ip_len - (size_ip + tcp_size); if ((int32_t)size_payload > 0) { // Get packet payload msg_payload = malloc(size_payload + 1); memset(msg_payload, 0, size_payload + 1); memcpy(msg_payload, (u_char *) (packet + size_link + size_ip + tcp_size), size_payload); } // Total packet size size_packet = size_link + size_ip + tcp_size + size_payload; #ifdef WITH_OPENSSL if (!msg_payload || !strstr((const char*) msg_payload, "SIP/2.0")) { if (capture_get_keyfile()) { // Allocate memory for the payload msg_payload = malloc(size_payload + 1); memset(msg_payload, 0, size_payload + 1); // Try to decrypt the packet tls_process_segment(ip4, &msg_payload, &size_payload); // Check if we have decoded payload if (size_payload <= 0) free(msg_payload); // Set Transport TLS transport = 2; } } #endif } else { // Not handled protocol return; } // Increase capture stats if (ip4->ip_v == 4 && capinfo.devices) { if(is_local_address(ip4->ip_src.s_addr)) { capinfo.local_ports[htons(sport)]++; capinfo.remote_ports[htons(dport)]++; } else { capinfo.remote_ports[htons(sport)]++; capinfo.local_ports[htons(dport)]++; } } // We're only interested in packets with payload if (size_payload <= 0) return; // Parse this header and payload msg = sip_load_message(header, ip_src, sport, ip_dst, dport, msg_payload); free(msg_payload); // This is not a sip message, Bye! if (!msg) return; // Store Transport attribute if (transport == 0) { msg_set_attribute(msg, SIP_ATTR_TRANSPORT, "UDP"); } else if (transport == 1) { msg_set_attribute(msg, SIP_ATTR_TRANSPORT, "TCP"); } else if (transport == 2) { msg_set_attribute(msg, SIP_ATTR_TRANSPORT, "TLS"); } // Set message PCAP data msg->pcap_packet = malloc(size_packet); memcpy(msg->pcap_packet, packet, size_packet); // Store this packets in output file dump_packet(capinfo.pd, header, packet); }