res_pjsip: Strip spaces from items parsed from comma-separated lists

Configurations like "aors = a, b, c" were either ignoring everything after "a"
or trying to look up " b".  Same for mailboxes,  ciphers, contacts and a few
others.

To fix, all the strsep(&copy, ",") calls have been wrapped in ast_strip.  To
facilitate this, ast_strip, ast_skip_blanks and ast_skip_nonblanks were
updated to handle null pointers.

In some cases, an ast_strlen_zero() test was added to skip consecutive commas.

There was also an attempt to ast_free an ast_strdupa'd string in
ast_sip_for_each_aor which was causing a SEGV.  I removed it.

Although this issue was reported for realtime, the issue was in the res_pjsip
modules so all config mechanisms were affected.

ASTERISK-25829 #close
Reported-by: Mateusz Kowalski

Change-Id: I0b22a2cf22a7c1c50d4ecacbfa540155bec0e7a2

1 files changed, 19 insertions, 7 deletions

diff --git a/res/res_pjsip_mwi.c b/res/res_pjsip_mwi.c
index e1eea6f2a..c9d1b743e 100644
--- a/res/res_pjsip_mwi.c
+++ b/res/res_pjsip_mwi.c
@@ -432,7 +432,7 @@ static void send_unsolicited_mwi_notify(struct mwi_subscription *sub,
 	ast_debug(5, "Sending unsolicited MWI NOTIFY to endpoint %s, new messages: %d, old messages: %d\n",
 			sub->id, counter->new_msgs, counter->old_msgs);
 
-	while ((aor_name = strsep(&endpoint_aors, ","))) {
+	while ((aor_name = ast_strip(strsep(&endpoint_aors, ",")))) {
 		RAII_VAR(struct ast_sip_aor *, aor, ast_sip_location_retrieve_aor(aor_name), ao2_cleanup);
 		RAII_VAR(struct ao2_container *, contacts, NULL, ao2_cleanup);
 		struct unsolicited_mwi_data mwi_data = {
@@ -598,7 +598,11 @@ static int mwi_validate_for_aor(void *obj, void *arg, int flags)
 	}
 
 	mailboxes = ast_strdupa(aor->mailboxes);
-	while ((mailbox = strsep(&mailboxes, ","))) {
+	while ((mailbox = ast_strip(strsep(&mailboxes, ",")))) {
+		if (ast_strlen_zero(mailbox)) {
+			continue;
+		}
+
 		if (endpoint_receives_unsolicited_mwi_for_mailbox(endpoint, mailbox)) {
 			ast_debug(1, "Endpoint '%s' already configured for unsolicited MWI for mailbox '%s'. "
 					"Denying MWI subscription to %s\n", ast_sorcery_object_get_id(endpoint), mailbox,
@@ -622,9 +626,13 @@ static int mwi_on_aor(void *obj, void *arg, int flags)
 	}
 
 	mailboxes = ast_strdupa(aor->mailboxes);
-	while ((mailbox = strsep(&mailboxes, ","))) {
+	while ((mailbox = ast_strip(strsep(&mailboxes, ",")))) {
 		struct mwi_stasis_subscription *mwi_stasis_sub;
 
+		if (ast_strlen_zero(mailbox)) {
+			continue;
+		}
+
 		mwi_stasis_sub = mwi_stasis_subscription_alloc(mailbox, sub);
 		if (!mwi_stasis_sub) {
 			continue;
@@ -890,7 +898,7 @@ static int create_mwi_subscriptions_for_endpoint(void *obj, void *arg, int flags
 
 	endpoint_aors = ast_strdupa(endpoint->aors);
 
-	while ((aor_name = strsep(&endpoint_aors, ","))) {
+	while ((aor_name = ast_strip(strsep(&endpoint_aors, ",")))) {
 		RAII_VAR(struct ast_sip_aor *, aor, ast_sip_location_retrieve_aor(aor_name), ao2_cleanup);
 
 		if (!aor) {
@@ -921,11 +929,15 @@ static int create_mwi_subscriptions_for_endpoint(void *obj, void *arg, int flags
 	}
 
 	mailboxes = ast_strdupa(endpoint->subscription.mwi.mailboxes);
-	while ((mailbox = strsep(&mailboxes, ","))) {
-		struct mwi_subscription *sub = aggregate_sub ?:
-			mwi_subscription_alloc(endpoint, 0, NULL);
+	while ((mailbox = ast_strip(strsep(&mailboxes, ",")))) {
+		struct mwi_subscription *sub;
 		struct mwi_stasis_subscription *mwi_stasis_sub;
 
+		if (ast_strlen_zero(mailbox)) {
+			continue;
+		}
+
+		sub = aggregate_sub ?: mwi_subscription_alloc(endpoint, 0, NULL);
 		mwi_stasis_sub = mwi_stasis_subscription_alloc(mailbox, sub);
 		if (mwi_stasis_sub) {
 			ao2_link(sub->stasis_subs, mwi_stasis_sub);