[svn-commits] mmichelson: branch 1.4 r181990 - /branches/1.4/res/res_features.c

[SVN commits to the Digium repositories]

Author: mmichelson
Date: Fri Mar 13 12:12:32 2009
New Revision: 181990

URL: http://svn.digium.com/svn-view/asterisk?view=rev&rev=181990
Log:
Check the DYNAMIC_FEATURES of both the chan and peer when interpreting DTMF.

Dynamic features defined in the applicationmap section of features.conf allow
one to specify whether the caller, callee, or both have the ability to use the
feature. The documentation in the features.conf.sample file could be interpreted
to mean that one only needs to set the DYNAMIC_FEATURES channel variable on the
calling channel in order to allow for the callee to be able to use the features
which he should have permission to use. However, the DYNAMIC_FEATURES variable
would only be read from the channel of the participant that pressed the DTMF
sequence to activate the feature. The result of this was that the callee was
unable to use dynamic features unless the dialplan writer had taken measures
to be sure that the DYNAMIC_FEATURES variable was set on the callee's channel.

This commit changes the behavior of ast_feature_interpret to concatenate the
values of DYNAMIC_FEATURES from both parties involved in the bridge. The features
themselves determine who has permission to use them, so there is no reason to believe
that one side of the bridge could gain the ability to perform an action that they
should not have the ability to perform.

Kevin Fleming pointed out on the asterisk-users list that the typical way that this
was worked around in the past was by setting _DYNAMIC_FEATURES on the calling channel
so that the value would be inherited by the called channel. While this works, the
documentation alone is not enough to figure out why this is necessary for the callee
to be able to use dynamic features. In this particular case, changing the code to match
the documentation is safe, easy, and will generally make things easier for people for
future installations.

This bug was originally reported on the asterisk-users list by David Ruggles.

(closes issue #14657)
Reported by: mmichelson
Patches:
      14657.patch uploaded by mmichelson (license 60)


Modified:
    branches/1.4/res/res_features.c

Modified: branches/1.4/res/res_features.c
URL: http://svn.digium.com/svn-view/asterisk/branches/1.4/res/res_features.c?view=diff&rev=181990&r1=181989&r2=181990
==============================================================================
--- branches/1.4/res/res_features.c (original)
+++ branches/1.4/res/res_features.c Fri Mar 13 12:12:32 2009
@@ -1228,20 +1228,30 @@
 	int x;
 	struct ast_flags features;
 	struct ast_call_feature *feature;
-	const char *dynamic_features;
+	const char *peer_dynamic_features, *chan_dynamic_features;
+	char dynamic_features_buf[128];
 	char *tmp, *tok;
 	int res = FEATURE_RETURN_PASSDIGITS;
 	int feature_detected = 0;
 
 	if (sense == FEATURE_SENSE_CHAN) {
-		ast_copy_flags(&features, &(config->features_caller), AST_FLAGS_ALL);	
-		dynamic_features = pbx_builtin_getvar_helper(chan, "DYNAMIC_FEATURES");
+		ast_copy_flags(&features, &(config->features_caller), AST_FLAGS_ALL);
 	} else {
 		ast_copy_flags(&features, &(config->features_callee), AST_FLAGS_ALL);	
-		dynamic_features = pbx_builtin_getvar_helper(peer, "DYNAMIC_FEATURES");
-	}
+	}
+
+	ast_channel_lock(peer);
+	peer_dynamic_features = ast_strdupa(S_OR(pbx_builtin_getvar_helper(peer, "DYNAMIC_FEATURES"),""));
+	ast_channel_unlock(peer);
+
+	ast_channel_lock(chan);
+	chan_dynamic_features = ast_strdupa(S_OR(pbx_builtin_getvar_helper(chan, "DYNAMIC_FEATURES"),""));
+	ast_channel_unlock(chan);
+
+	snprintf(dynamic_features_buf, sizeof(dynamic_features_buf), "%s%s%s", S_OR(chan_dynamic_features, ""), chan_dynamic_features && peer_dynamic_features ? "#" : "", S_OR(peer_dynamic_features,""));
+
 	if (option_debug > 2)
-		ast_log(LOG_DEBUG, "Feature interpret: chan=%s, peer=%s, code=%s, sense=%d, features=%d dynamic=%s\n", chan->name, peer->name, code, sense, features.flags, dynamic_features);
+		ast_log(LOG_DEBUG, "Feature interpret: chan=%s, peer=%s, code=%s, sense=%d, features=%d dynamic=%s\n", chan->name, peer->name, code, sense, features.flags, dynamic_features_buf);
 
 	ast_rwlock_rdlock(&features_lock);
 	for (x = 0; x < FEATURES_COUNT; x++) {
@@ -1263,13 +1273,14 @@
 	}
 	ast_rwlock_unlock(&features_lock);
 
-	if (ast_strlen_zero(dynamic_features) || feature_detected)
+	if (ast_strlen_zero(dynamic_features_buf) || feature_detected) {
 		return res;
-
-	tmp = ast_strdupa(dynamic_features);
+	}
+
+	tmp = dynamic_features_buf;
 
 	while ((tok = strsep(&tmp, "#"))) {
-		AST_RWLIST_RDLOCK(&feature_list);	
+		AST_RWLIST_RDLOCK(&feature_list);
 		if (!(feature = find_dynamic_feature(tok))) {
 			AST_RWLIST_UNLOCK(&feature_list);
 			continue;