Asterisk - The Open Source Telephony Project  21.4.1
res_pjsip_rfc3326.c
1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2013, Digium, Inc.
5  *
6  * Joshua Colp <jcolp@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18 
19 /*** MODULEINFO
20  <depend>pjproject</depend>
21  <depend>res_pjsip</depend>
22  <depend>res_pjsip_session</depend>
23  <support_level>core</support_level>
24  ***/
25 
26 #include "asterisk.h"
27 
28 #include <pjsip.h>
29 #include <pjsip_ua.h>
30 
31 #include "asterisk/res_pjsip.h"
32 #include "asterisk/res_pjsip_session.h"
33 #include "asterisk/module.h"
34 #include "asterisk/causes.h"
35 #include "asterisk/threadpool.h"
36 
37 static void rfc3326_use_reason_header(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
38 {
39  static const pj_str_t str_reason = { "Reason", 6 };
40  pjsip_generic_string_hdr *header;
41  char buf[20];
42  char *cause;
43  int code_q850 = 0, code_sip = 0;
44 
45  header = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &str_reason, NULL);
46  for (; header;
47  header = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &str_reason, header->next)) {
48  int cause_q850, cause_sip;
49  ast_copy_pj_str(buf, &header->hvalue, sizeof(buf));
50  cause = ast_skip_blanks(buf);
51 
52  cause_q850 = !strncasecmp(cause, "Q.850", 5);
53  cause_sip = !strncasecmp(cause, "SIP", 3);
54  if ((cause_q850 || cause_sip) && (cause = strstr(cause, "cause="))) {
55  int *code = cause_q850 ? &code_q850 : &code_sip;
56  if (sscanf(cause, "cause=%30d", code) != 1) {
57  *code = 0;
58  }
59  }
60  }
61 
62  if (code_q850) {
63  ast_channel_hangupcause_set(session->channel, code_q850 & 0x7f);
64  } else if (code_sip) {
65  ast_channel_hangupcause_set(session->channel, ast_sip_hangup_sip2cause(code_sip));
66  }
67 }
68 
69 static int rfc3326_incoming_request(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
70 {
71  if ((pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, &pjsip_bye_method) &&
72  pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, &pjsip_cancel_method)) ||
73  !session->channel) {
74  return 0;
75  }
76 
77  rfc3326_use_reason_header(session, rdata);
78 
79  return 0;
80 }
81 
82 static void rfc3326_incoming_response(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
83 {
84  struct pjsip_status_line status = rdata->msg_info.msg->line.status;
85 
86  if ((status.code < 300) || !session->channel) {
87  return;
88  }
89 
90  rfc3326_use_reason_header(session, rdata);
91 }
92 
93 static void rfc3326_add_reason_header(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
94 {
95  char buf[20];
96 
97  if (ast_channel_hangupcause(session->channel) == AST_CAUSE_ANSWERED_ELSEWHERE) {
98  ast_sip_add_header(tdata, "Reason", "SIP;cause=200;text=\"Call completed elsewhere\"");
99  }
100 
101  if (session->endpoint && session->endpoint->suppress_q850_reason_headers) {
102  ast_debug(1, "A Q.850 '%s'(%i) Reason header was suppressed for endpoint '%s'\n",
103  ast_cause2str((ast_channel_hangupcause(session->channel) & 0x7f)),
104  (ast_channel_hangupcause(session->channel) & 0x7f),
106  } else {
107  snprintf(buf, sizeof(buf), "Q.850;cause=%i", ast_channel_hangupcause(session->channel) & 0x7f);
108  ast_sip_add_header(tdata, "Reason", buf);
109  }
110 }
111 
112 static void rfc3326_outgoing_request(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
113 {
114  if ((pjsip_method_cmp(&tdata->msg->line.req.method, &pjsip_bye_method)
115  && pjsip_method_cmp(&tdata->msg->line.req.method, &pjsip_cancel_method))
116  || !session->channel
117  /*
118  * The session->channel has been seen to go away on us between
119  * checks so we must also be running under the call's serializer
120  * thread.
121  */
122  || session->serializer != ast_threadpool_serializer_get_current()) {
123  return;
124  }
125 
126  rfc3326_add_reason_header(session, tdata);
127 }
128 
129 static void rfc3326_outgoing_response(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
130 {
131  struct pjsip_status_line status = tdata->msg->line.status;
132 
133  if (status.code < 300
134  || !session->channel
135  || session->serializer != ast_threadpool_serializer_get_current()) {
136  return;
137  }
138 
139  rfc3326_add_reason_header(session, tdata);
140 }
141 
142 static struct ast_sip_session_supplement rfc3326_supplement = {
143  .incoming_request = rfc3326_incoming_request,
144  .incoming_response = rfc3326_incoming_response,
145  .outgoing_request = rfc3326_outgoing_request,
146  .outgoing_response = rfc3326_outgoing_response,
147 };
148 
149 static int load_module(void)
150 {
151  ast_sip_session_register_supplement(&rfc3326_supplement);
153 }
154 
155 static int unload_module(void)
156 {
157  ast_sip_session_unregister_supplement(&rfc3326_supplement);
158  return 0;
159 }
160 
161 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP RFC3326 Support",
162  .support_level = AST_MODULE_SUPPORT_CORE,
163  .load = load_module,
164  .unload = unload_module,
165  .load_pri = AST_MODPRI_APP_DEPEND,
166  .requires = "res_pjsip,res_pjsip_session",
167 );
struct ast_sip_endpoint * endpoint
Asterisk main include file. File version handling, generic pbx functions.
int(* incoming_request)(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
Called on incoming SIP request This method can indicate a failure in processing in its return...
const char * ast_cause2str(int cause) attribute_pure
Gives the string form of a given cause code.
Definition: channel.c:612
A structure describing a SIP session.
const char * ast_sorcery_object_get_id(const void *object)
Get the unique identifier of a sorcery object.
Definition: sorcery.c:2317
struct ast_channel * channel
#define ast_debug(level,...)
Log a DEBUG message.
struct ast_taskprocessor * serializer
char * ast_skip_blanks(const char *str)
Gets a pointer to the first non-whitespace character in a string.
Definition: strings.h:161
A supplement to SIP message processing.
Internal Asterisk hangup causes.
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:46
Asterisk module definitions.
unsigned int suppress_q850_reason_headers
Definition: res_pjsip.h:1038