/*
* The function creates an ACK to 200 OK. Route set will be created
* and parsed and the dst parameter will contain the destination to which
* the request should be send. The function is used by tm when it
* generates local ACK to 200 OK (on behalf of applications using uac)
*/
char *build_dlg_ack(struct sip_msg* rpl, struct cell *Trans,
unsigned int branch, str *hdrs, str *body,
unsigned int *len, struct dest_info* dst)
{
char *req_buf, *p, *via;
unsigned int via_len;
char branch_buf[MAX_BRANCH_PARAM_LEN];
int branch_len;
str branch_str;
struct hostport hp;
struct rte* list;
str contact, ruri, *cont;
str next_hop;
str body_len;
str _to, *to = &_to;
#ifdef USE_DNS_FAILOVER
struct dns_srv_handle dns_h;
#endif
#ifdef WITH_AS_SUPPORT
/* With AS support, TM allows for external modules to generate building of
* the ACK; in this case, the ACK's retransmission buffer is built once
* and kept in memory (to help when retransmitted 2xx are received and ACK
* must be resent).
* Allocation of the string raw buffer that holds the ACK is piggy-backed
* with allocation of the retransmission buffer (since both have the same
* life-cycle): both the string buffer and retransm. buffer are placed
* into the same allocated chunk of memory (retr. buffer first, string
* buffer follows).In this case, the 'len' param is used as in-out
* parameter: 'in' to give the extra space needed by the retr. buffer,
* 'out' to return the lenght of the allocated string buffer.
*/
unsigned offset = *len;
#endif
if (parse_headers(rpl, HDR_EOH_F, 0) == -1 || !rpl->to) {
LM_ERR("Error while parsing headers.\n");
return 0;
} else {
_to.s = rpl->to->name.s;
_to.len = rpl->to->len;
}
if (get_contact_uri(rpl, &contact) < 0) {
return 0;
}
if (eval_uac_routing(rpl, &Trans->uac[branch].request, &contact,
&list, &ruri, &next_hop) < 0) {
LM_ERR("failed to evaluate routing elements.\n");
return 0;
}
LM_DBG("ACK RURI: `%.*s', NH: `%.*s'.\n", STR_FMT(&ruri),
STR_FMT(&next_hop));
if ((contact.s != ruri.s) || (contact.len != ruri.len)) {
/* contact != ruri means that the next
* hop is a strict router, cont will be non-zero
* and print_routeset will append it at the end
* of the route set
*/
cont = &contact;
} else {
/* Next hop is a loose router, nothing to append */
cont = 0;
}
/* method, separators, version: "ACK sip:[email protected] SIP/2.0" */
*len = SIP_VERSION_LEN + ACK_LEN + 2 /* spaces */ + CRLF_LEN;
*len += ruri.len;
/* dst */
switch(cfg_get(tm, tm_cfg, local_ack_mode)){
case 1:
/* send the local 200 ack to the same dst as the corresp. invite*/
*dst=Trans->uac[branch].request.dst;
break;
case 2:
/* send the local 200 ack to the same dst as the 200 reply source*/
init_dst_from_rcv(dst, &rpl->rcv);
dst->send_flags=rpl->fwd_send_flags;
break;
case 0:
default:
/* rfc conformant behaviour: use the next_hop determined from the
* contact and the route set */
#ifdef USE_DNS_FAILOVER
if (cfg_get(core, core_cfg, use_dns_failover)){
dns_srv_handle_init(&dns_h);
if ((uri2dst(&dns_h , dst, rpl, &next_hop, PROTO_NONE)==0) ||
(dst->send_sock==0)){
dns_srv_handle_put(&dns_h);
LM_ERR("no socket found\n");
goto error;
}
dns_srv_handle_put(&dns_h); /* not needed any more */
}else{
if ((uri2dst(0 , dst, rpl, &next_hop, PROTO_NONE)==0) ||
(dst->send_sock==0)){
LM_ERR("no socket found\n");
goto error;
}
}
#else /* USE_DNS_FAILOVER */
if ( (uri2dst( dst, rpl, &next_hop, PROTO_NONE)==0) ||
(dst->send_sock==0)){
LM_ERR("no socket found\n");
goto error;
}
#endif /* USE_DNS_FAILOVER */
break;
}
/* via */
if (!t_calc_branch(Trans, branch, branch_buf, &branch_len)) goto error;
branch_str.s = branch_buf;
branch_str.len = branch_len;
set_hostport(&hp, 0);
via = via_builder(&via_len, NULL, dst, &branch_str, 0, &hp);
if (!via) {
LM_ERR("No via header got from builder\n");
goto error;
}
*len+= via_len;
/* headers */
*len += Trans->from.len + Trans->callid.len + to->len + Trans->cseq_n.len + 1 + ACK_LEN + CRLF_LEN;
/* copy'n'paste Route headers */
*len += calc_routeset_len(list, cont);
/* User Agent */
if (server_signature) *len += user_agent_hdr.len + CRLF_LEN;
/* extra headers */
if (hdrs)
*len += hdrs->len;
/* body */
if (body) {
body_len.s = int2str(body->len, &body_len.len);
*len += body->len;
} else {
body_len.len = 0;
body_len.s = NULL; /*4gcc*/
*len += 1; /* for the (Cont-Len:) `0' */
}
/* Content Length, EoM */
*len += CONTENT_LENGTH_LEN + body_len.len + CRLF_LEN + CRLF_LEN;
#if WITH_AS_SUPPORT
req_buf = shm_malloc(offset + *len + 1);
req_buf += offset;
#else
req_buf = shm_malloc(*len + 1);
#endif
if (!req_buf) {
LM_ERR("Cannot allocate memory (%u+1)\n", *len);
goto error01;
}
p = req_buf;
append_str( p, ACK, ACK_LEN );
append_str( p, " ", 1 );
append_str(p, ruri.s, ruri.len);
append_str( p, " " SIP_VERSION CRLF, 1 + SIP_VERSION_LEN + CRLF_LEN);
/* insert our via */
append_str(p, via, via_len);
/*other headers*/
append_str(p, Trans->from.s, Trans->from.len);
append_str(p, Trans->callid.s, Trans->callid.len);
append_str(p, to->s, to->len);
append_str(p, Trans->cseq_n.s, Trans->cseq_n.len);
append_str( p, " ", 1 );
append_str( p, ACK, ACK_LEN);
append_str(p, CRLF, CRLF_LEN);
/* Routeset */
p = print_rs(p, list, cont);
/* User Agent header */
if (server_signature) {
append_str(p, user_agent_hdr.s, user_agent_hdr.len);
append_str(p, CRLF, CRLF_LEN);
}
/* extra headers */
if (hdrs)
append_str(p, hdrs->s, hdrs->len);
/* Content Length, EoH, (body) */
if (body) {
append_str(p, CONTENT_LENGTH, CONTENT_LENGTH_LEN);
append_str(p, body_len.s, body_len.len);
append_str(p, /*end crr. header*/CRLF /*EoH*/CRLF, CRLF_LEN +
CRLF_LEN);
append_str(p, body->s, body->len);
} else {
append_str(p, CONTENT_LENGTH "0" CRLF CRLF,
CONTENT_LENGTH_LEN + 1 + CRLF_LEN + CRLF_LEN);
}
/* EoM */
*p = 0;
pkg_free(via);
free_rte_list(list);
return req_buf;
error01:
pkg_free(via);
error:
free_rte_list(list);
return 0;
}
/*
* The function creates an ACK for a local INVITE. If 200 OK, route set
* will be created and parsed
*/
char *build_dlg_ack(struct sip_msg* rpl, struct cell *Trans,
unsigned int branch, str* to, unsigned int *len)
{
char *req_buf, *p, *via;
unsigned int via_len;
char branch_buf[MAX_BRANCH_PARAM_LEN];
int branch_len;
str branch_str;
struct hostport hp;
struct rte* list;
str contact, ruri, *cont;
struct socket_info* send_sock;
str next_hop;
if (rpl->first_line.u.reply.statuscode < 300 ) {
/* build e2e ack for 2xx reply -> we need the route set */
if (get_contact_uri(rpl, &contact) < 0) {
return 0;
}
if (process_routeset(rpl, &contact, &list, &ruri, &next_hop) < 0) {
return 0;
}
if ((contact.s != ruri.s) || (contact.len != ruri.len)) {
/* contact != ruri means that the next
* hop is a strict router, cont will be non-zero
* and print_routeset will append it at the end
* of the route set
*/
cont = &contact;
} else {
/* Next hop is a loose router, nothing to append */
cont = 0;
}
} else {
/* build hop-by-hop ack for negative reply ->
* ruri is the same as in INVITE; no route set */
ruri = Trans->uac[branch].uri;
cont = 0;
list = 0;
}
/* method, separators, version: "ACK sip:[email protected] SIP/2.0" */
*len = SIP_VERSION_LEN + ACK_LEN + 2 /* spaces */ + CRLF_LEN;
*len += ruri.len;
/* use same socket as for INVITE -bogdan */
send_sock = Trans->uac[branch].request.dst.send_sock;
if (!t_calc_branch(Trans, branch, branch_buf, &branch_len)) goto error;
branch_str.s = branch_buf;
branch_str.len = branch_len;
set_hostport(&hp, 0);
/* build via */
via = via_builder(&via_len, send_sock, &branch_str, 0,
send_sock->proto, &hp);
if (!via) {
LM_ERR("no via header got from builder\n");
goto error;
}
*len+= via_len;
/*headers*/
*len += Trans->from.len + Trans->callid.len + to->len +
Trans->cseq_n.len + 1 + ACK_LEN + CRLF_LEN;
/* copy'n'paste Route headers */
*len += calc_routeset_len(list, cont);
/* User Agent */
if (server_signature)
*len += user_agent_header.len + CRLF_LEN;
/* Content Length, EoM */
*len += CONTENT_LENGTH_LEN + 1 + CRLF_LEN + CRLF_LEN;
req_buf = shm_malloc(*len + 1);
if (!req_buf) {
LM_ERR("no more share memory\n");
goto error01;
}
p = req_buf;
append_string( p, ACK " ", ACK_LEN+1 );
append_string(p, ruri.s, ruri.len );
append_string( p, " " SIP_VERSION CRLF, 1 + SIP_VERSION_LEN + CRLF_LEN);
/* insert our via */
append_string(p, via, via_len);
/*other headers*/
append_string(p, Trans->from.s, Trans->from.len);
append_string(p, Trans->callid.s, Trans->callid.len);
append_string(p, to->s, to->len);
append_string(p, Trans->cseq_n.s, Trans->cseq_n.len);
*(p++) = ' ';
append_string(p, ACK CRLF, ACK_LEN+CRLF_LEN);
/* Routeset */
p = print_rs(p, list, cont);
/* User Agent header, Content Length, EoM */
if (server_signature) {
append_string(p, user_agent_header.s, user_agent_header.len);
append_string(p, CRLF CONTENT_LENGTH "0" CRLF CRLF,
CRLF_LEN+CONTENT_LENGTH_LEN + 1 + CRLF_LEN + CRLF_LEN);
} else {
append_string(p, CONTENT_LENGTH "0" CRLF CRLF,
CONTENT_LENGTH_LEN + 1 + CRLF_LEN + CRLF_LEN);
}
*p = 0;
pkg_free(via);
free_rte_list(list);
return req_buf;
error01:
pkg_free(via);
error:
free_rte_list(list);
return 0;
}
