FreeCalypso > hg > themwi-system-sw
diff sip-in/invite_init.c @ 145:4b685a5d9bd4
sip-in code: split invite.c into 3 separate C modules
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 08 Oct 2022 19:31:05 -0800 |
parents | sip-in/invite.c@c93c339271a7 |
children | 257da5474e77 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/sip-in/invite_init.c Sat Oct 08 19:31:05 2022 -0800 @@ -0,0 +1,302 @@ +/* + * Here we implement our initial processing of SIP INVITE requests. + */ + +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <netinet/in.h> +#include <stdio.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <strings.h> +#include <syslog.h> +#include "../libsip/parse.h" +#include "../libsip/uas_basic.h" +#include "../libsip/grok_from.h" +#include "../libsip/req_supp.h" +#include "../libsip/sdp.h" +#include "../libsip/out_msg.h" +#include "call.h" + +extern struct in_addr sip_bind_ip; +extern int cfg_use_100rel; +extern int cfg_force_pcma; +extern struct call *call_list; + +extern struct call *find_call_by_sip_id(); +extern char *get_single_header(); + +void +invite_new_call(req, ess, sin) + struct sip_pkt_rx *req; + struct uas_parse_hdrs *ess; + struct sockaddr_in *sin; +{ + static unsigned cycle_tag_num, cycle_sdp_addend; + char uri_user[13], *called_nanp; + struct sip_msg_out resp; + struct grok_from gfrom; + struct supported_ext supp_ext; + char *hval, *unsup_ext; + int ext_100rel_req, ext_100rel_sup, use_100rel, use_pcma; + struct sdp_parse sdp_parse; + struct sdp_gen sdp_gen; + struct call *call; + char *dp, cdr_str[80]; + unsigned cdr_num_len, cdr_cnam_len; + unsigned req_uri_len, to_hdr_len, copylen; + int rc; + + /* extract called number from Request-URI */ + rc = user_from_sip_uri(req->req_uri, uri_user, 12); + if (rc < 0) { +not_nanp: start_response_out_msg(&resp, + "416 Request-URI is not a NANP number"); +error_resp: rc = add_resp_basic_headers(&resp, ess, req->req_method); + if (rc < 0) { +error_resp_toolong: syslog(LOG_ERR, + "INVITE early error response length exceeded"); + return; + } + out_msg_finish(&resp); + sip_tx_packet(&resp, sin); + return; + } + if (uri_user[0] == '+') { + if (grok_number_string(uri_user+1, 0) != 11 || + uri_user[1] != '1') + goto not_nanp; + called_nanp = uri_user + 2; + } else switch (grok_number_string(uri_user)) { + case 10: + called_nanp = uri_user; + break; + case 11: + if (uri_user[0] != '1') + goto not_nanp; + called_nanp = uri_user + 1; + break; + default: + goto not_nanp; + } + if (!is_nanp_valid_prefix(called_nanp)) + goto not_nanp; + /* it is valid NANP - but is it one of ours? */ + refresh_number_db(); + if (!is_nanp_locally_owned(called_nanp)) { + start_response_out_msg(&resp, + "404 Called number does not belong here"); + goto error_resp; + } + /* parse and validate From header */ + rc = grok_from_header(ess->from, &gfrom); + if (rc < 0) { + start_response_out_msg(&resp, "400 Malformed From header"); + goto error_resp; + } + /* validate To header for the purpose of tag addition */ + req_uri_len = strlen(req->req_uri); + to_hdr_len = strlen(ess->to); + if (to_hdr_len == req_uri_len) { + if (strcasecmp(ess->to, req->req_uri)) { +bad_to_header: start_response_out_msg(&resp, "400 Bad To header"); + goto error_resp; + } + } else if (to_hdr_len == req_uri_len + 2) { + if (ess->to[0] != '<') + goto bad_to_header; + if (strncasecmp(ess->to+1, req->req_uri, req_uri_len)) + goto bad_to_header; + if (ess->to[req_uri_len+1] != '>') + goto bad_to_header; + } else + goto bad_to_header; + /* check 100rel and catch any unsupported requirements */ + supp_ext.name = "100rel"; + supp_ext.req_flag = &ext_100rel_req; + supp_ext.sup_flag = &ext_100rel_sup; + ext_100rel_req = ext_100rel_sup = 0; + rc = parse_require_supported(req, &supp_ext, 1, &unsup_ext); + if (rc < 0) { + start_response_out_msg(&resp, "420 Extension not supported"); + rc = out_msg_add_header(&resp, "Unsupported", unsup_ext); + if (rc < 0) + goto error_resp_toolong; + goto error_resp; + } + if (ext_100rel_req) + use_100rel = 1; + else if (ext_100rel_sup) + use_100rel = cfg_use_100rel; + else + use_100rel = 0; + /* did the caller send an SDP message body? */ + if (!req->msg_body_len) { + start_response_out_msg(&resp, "415 Missing SDP body"); +error_415: rc = out_msg_add_header(&resp, "Accept", "application/sdp"); + if (rc < 0) + goto error_resp_toolong; + goto error_resp; + } + hval = get_single_header(req, "Content-Type", "c", (int *) 0); + if (!hval) { + start_response_out_msg(&resp, + "415 Missing Content-Type header"); + goto error_415; + } + if (strcasecmp(hval, "application/sdp")) { + start_response_out_msg(&resp, "415 Unsupported Content-Type"); + goto error_415; + } + rc = parse_incoming_sdp(req->msg_body, req->msg_body_len, &sdp_parse); + if (rc < 0) { + start_response_out_msg(&resp, "488 Malformed SDP body"); + goto error_resp; + } + switch (sdp_parse.codec_mask) { + case SDP_CODEC_MASK_PCMU: + use_pcma = 0; + break; + case SDP_CODEC_MASK_PCMA: + case SDP_CODEC_MASK_BOTH | SDP_CODEC_MASK_PCMA_PREF: + use_pcma = 1; + break; + case SDP_CODEC_MASK_BOTH: + use_pcma = cfg_force_pcma; + break; + default: + start_response_out_msg(&resp, + "488 Unsupported codec selection"); + rc = add_resp_basic_headers(&resp, ess, req->req_method); + if (rc < 0) + goto error_resp_toolong; + rc = out_msg_add_header(&resp, "Content-Type", + "application/sdp"); + if (rc < 0) + goto error_resp_toolong; + bzero(&sdp_gen, sizeof sdp_gen); + sdp_gen.owner_ip = sip_bind_ip; + sdp_gen.conn_ip = sip_bind_ip; + sdp_gen.codec_mask = SDP_CODEC_MASK_BOTH; + rc = out_msg_finish_sdp(&resp, &sdp_gen); + if (rc < 0) + goto error_resp_toolong; + sip_tx_packet(&resp, sin); + return; + } + /* SIP INVITE validation done - gather CDR info */ + cdr_num_len = gfrom.user_len; + if (cdr_num_len > 33) + cdr_num_len = 33; + cdr_cnam_len = gfrom.cnam_len; + if (cdr_cnam_len > 33) + cdr_cnam_len = 33; + if (cdr_cnam_len) + sprintf(cdr_str, "%.*s (%s%.*s%s)", cdr_num_len, gfrom.user, + gfrom.cnam_quoted ? "\"" : "", cdr_cnam_len, gfrom.cnam, + gfrom.cnam_quoted ? "\"" : ""); + else + sprintf(cdr_str, "%.*s", cdr_num_len, gfrom.user); + hval = get_single_header(req, "P-Asserted-Identity", (char *) 0, + (int *) 0); + /* check if GSM service is up */ + rc = connect_gsm_mtcall(); + if (rc < 0) { +gsm_offline: syslog(LOG_INFO, "Down-call from %s to %s", cdr_str, uri_user); + if (hval) + syslog(LOG_INFO, "Down-call PAI: %.100s", hval); + start_response_out_msg(&resp, "480 GSM service is offline"); + goto error_resp; + } + rc = connect_tmgw_socket(); + if (rc < 0) + goto gsm_offline; + /* stateful processing begins */ + call = malloc(sizeof(struct call) + strlen(ess->call_id) + + strlen(ess->from) + req_uri_len + strlen(ess->via) + 19); + if (!call) { + syslog(LOG_CRIT, "failed malloc for incoming call!"); + start_response_out_msg(&resp, + "503 Gateway resource allocation failure"); + goto error_resp; + } + cycle_tag_num++; + if (cycle_tag_num >= 1000000) + cycle_tag_num = 0; + cycle_sdp_addend++; + if (cycle_sdp_addend >= 0x10000) + cycle_sdp_addend = 0; + bzero(call, sizeof(struct call)); + dp = (char *)(call + 1); + copylen = strlen(ess->call_id) + 1; + call->sip_call_id = dp; + bcopy(ess->call_id, dp, copylen); + dp += copylen; + copylen = strlen(ess->from) + 1; + call->invite_from = dp; + bcopy(ess->from, dp, copylen); + dp += copylen; + call->invite_to = dp; + *dp++ = '<'; + bcopy(req->req_uri, dp, req_uri_len); + dp += req_uri_len; + *dp++ = '>'; + sprintf(dp, ";tag=in%06u", cycle_tag_num); + dp += 14; + copylen = strlen(ess->via) + 1; + call->invite_via = dp; + bcopy(ess->via, dp, copylen); + call->invite_cseq = ess->cseq_num; + bcopy(sin, &call->udp_sin, sizeof(struct sockaddr_in)); + bcopy(called_nanp, call->called_nanp, 11); + call->from_uri = call->invite_from + (gfrom.uri - ess->from); + call->from_uri_len = gfrom.uri_len; + call->from_user = call->invite_from + (gfrom.user - ess->from); + call->from_user_len = gfrom.user_len; + call->use_100rel = use_100rel; + call->pstn_rtp_remote.sin_family = AF_INET; + call->pstn_rtp_remote.sin_addr = sdp_parse.ip_addr; + call->pstn_rtp_remote.sin_port = htons(sdp_parse.audio_port); + call->use_pcma = use_pcma; + call->in_tag_num = cycle_tag_num; + call->sdp_addend = cycle_sdp_addend; + /* generate 100 response */ + start_response_out_msg(&resp, "100 Proceeding"); + rc = fill_invite_resp_from_call(&resp, call); + if (rc < 0) { + syslog(LOG_ERR, "INVITE 100 response length exceeded"); + free(call); + return; + } + out_msg_finish(&resp); + sip_tx_packet(&resp, sin); + /* add to call list */ + call->next = call_list; + call_list = call; + syslog(LOG_INFO, "Call in%06u from %s to %s", call->in_tag_num, + cdr_str, uri_user); + if (hval) + syslog(LOG_INFO, "Call in%06u PAI: %.100s", call->in_tag_num, + hval); + /* send CRCX to TMGW */ + tmgw_send_crcx(call); + call->overall_state = OVERALL_STATE_CRCX; + call->sip_state = SIP_STATE_INVITE_PROC; +} + +void +handle_sip_invite(req, ess, sin) + struct sip_pkt_rx *req; + struct uas_parse_hdrs *ess; + struct sockaddr_in *sin; +{ + struct call *call; + + call = find_call_by_sip_id(ess->call_id); + if (call) + invite_existing_call(req, ess, sin, call); + else + invite_new_call(req, ess, sin); +}