Add sip_watched_headers variable to launch events when a SIP message contains a given SIP header

FS-6801 #resolve

src/mod/endpoints/mod_sofia/mod_sofia.c

@@ -72,6 +72,7 @@ static switch_status_t sofia_kill_channel(switch_core_session_t *session, int si
 */
 static switch_status_t sofia_on_init(switch_core_session_t *session)
 {
+	const char *hval = NULL;
 	switch_channel_t *channel = switch_core_session_get_channel(session);
 	private_object_t *tech_pvt = (private_object_t *) switch_core_session_get_private(session);
 	switch_status_t status = SWITCH_STATUS_SUCCESS;
@@ -89,6 +90,23 @@ static switch_status_t sofia_on_init(switch_core_session_t *session)
 		switch_core_media_absorb_sdp(session);
 	}
 
+	if ((hval = switch_channel_get_variable(channel, "sip_watch_headers"))) {
+		char *dupvar = NULL;
+		char *watch_headers[10];
+		unsigned int numhdrs = 0;
+		int i = 0;
+		dupvar = switch_core_session_strdup(session, hval);
+		numhdrs = switch_separate_string(dupvar, ',', watch_headers, switch_arraylen(watch_headers));
+		if (numhdrs) {
+			char **wheaders = switch_core_session_alloc(session, ((numhdrs+1) * sizeof(wheaders[0])));
+			for (i = 0; i < numhdrs; i++) {
+				wheaders[i] = watch_headers[i];
+			}
+			wheaders[i] = NULL;
+			tech_pvt->watch_headers = wheaders;
+		}
+	}
+
 	if (switch_channel_test_flag(tech_pvt->channel, CF_RECOVERING) || switch_channel_test_flag(tech_pvt->channel, CF_RECOVERING_BRIDGE)) {
 		sofia_set_flag(tech_pvt, TFLAG_RECOVERED);
 	}

src/mod/endpoints/mod_sofia/mod_sofia.h

@@ -93,6 +93,7 @@ typedef struct private_object private_object_t;
 #define MY_EVENT_RECOVERY_RECOVERED "sofia::recovery_recovered"
 #define MY_EVENT_ERROR "sofia::error"
 #define MY_EVENT_PROFILE_START "sofia::profile_start"
+#define MY_EVENT_NOTIFY_WATCHED_HEADER "sofia::notify_watched_header"
 
 #define MULTICAST_EVENT "multicast::event"
 #define SOFIA_REPLACES_HEADER "_sofia_replaces_"
@@ -784,6 +785,7 @@ struct private_object {
 	sofia_cid_type_t cid_type;
 	uint32_t session_timeout;
 	enum nua_session_refresher session_refresher;
+	char **watch_headers;
 	char *respond_phrase;
 	int respond_code;
 	char *respond_dest;

src/mod/endpoints/mod_sofia/sofia.c

@@ -1251,6 +1251,21 @@ static void tech_send_ack(nua_handle_t *nh, private_object_t *tech_pvt)
 
 }
 
+static void notify_watched_header(switch_core_session_t *session, const char *msgline, const char *hdrname, const char *hdrval)
+{
+	switch_event_t *event = NULL;
+	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Found known watched header in message '%s', %s: %s\n", msgline, hdrname, hdrval);
+	if (switch_event_create_subclass(&event, SWITCH_EVENT_CUSTOM, MY_EVENT_NOTIFY_WATCHED_HEADER) == SWITCH_STATUS_SUCCESS) {
+		switch_channel_t *channel = switch_core_session_get_channel(session);
+		switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "SIP-Message", msgline);
+		switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "Header-Name", hdrname);
+		switch_event_add_header_string(event, SWITCH_STACK_BOTTOM, "Header-Value", hdrval);
+		switch_channel_event_set_data(channel, event);
+		switch_event_fire(&event);
+	} else {
+		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_CRIT, "Failed creating event of type %s!\n", MY_EVENT_NOTIFY_WATCHED_HEADER);
+	}
+}
 
 //sofia_dispatch_event_t *de
 static void our_sofia_event_callback(nua_event_t event,
@@ -1326,6 +1341,56 @@ static void our_sofia_event_callback(nua_event_t event,
 		}
 	}
 
+	if (session && tech_pvt && tech_pvt->watch_headers && sip) {
+		char msgline[512];
+		int hi;
+		msg_header_t *h = NULL;
+		if (sip->sip_request) {
+			h = (msg_header_t *)sip->sip_request;
+			msg_header_field_e(msgline, sizeof(msgline), h, 0);
+		} else if (sip->sip_status) {
+			h = (msg_header_t *)sip->sip_status;
+			msg_header_field_e(msgline, sizeof(msgline), h, 0);
+		}
+		if (h) {
+			sip_unknown_t *un = NULL;
+			char buf[512];
+			char *c = NULL;
+
+			msgline[sizeof(msgline)-1] = '\0';
+			c = strchr(msgline, '\r');
+			if (c) {
+				*c = '\0';
+			}
+
+			/* Faster (ie hash-based) search here would be nice? ie, make watch_headers a hash? */
+
+			/* Search first in the valid headers */
+			for (h = h->sh_succ; h; h = h->sh_succ) {
+				sip_header_t *sh = (sip_header_t *)h;
+				if (!sh->sh_class->hc_name) {
+					continue;
+				}
+				for (hi = 0; tech_pvt->watch_headers[hi]; hi++) {
+					if (!strcasecmp(tech_pvt->watch_headers[hi], sh->sh_class->hc_name)) {
+						msg_header_field_e(buf, sizeof(buf), h, 0);
+						buf[sizeof(buf)-1] = '\0';
+						notify_watched_header(session, msgline, sh->sh_class->hc_name, buf);
+					}
+				}
+			}
+
+			/* Search now in the unknown headers */
+			for (un = sip->sip_unknown; un; un = un->un_next) {
+				for (hi = 0; tech_pvt->watch_headers[hi]; hi++) {
+					if (!strcasecmp(tech_pvt->watch_headers[hi], un->un_name)) {
+						notify_watched_header(session, msgline, un->un_name, un->un_value);
+					}
+				}
+			}
+		}
+	}
+
 	if (sofia_test_pflag(profile, PFLAG_AUTH_ALL) && tech_pvt && tech_pvt->key && sip && (event < nua_r_set_params || event > nua_r_authenticate)) {
 		sip_authorization_t const *authorization = NULL;