Don't leak CID in From header when presentation=unavailable

When someone does Set(CALLERPRES()=unavailable) (or
Set(CALLERID(pres)=unavailable)) when sendrpid=no, the From header shows
"Anonymous" <anonymous@anonymous.invalid>. When sendrpid=yes/pai, the From
header will still display the callerid info, even though we supply an rpid
header with the anonymous info. It seems like we shouldn't leak that info in
any case. Skimming http://tools.ietf.org/html/draft-ietf-sip-privacy-04 seems
to indicate that one shouldn't send identifying info in the From in this case.

This patch anonymizes the From header as well even when sendrpid=yes/pai.

(closes issue ASTERISK-16538)

Review: https://reviewboard.asterisk.org/r/1649/
........

Merged revisions 349968 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@349977 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -12099,8 +12099,9 @@ static void initreqprep(struct sip_request *req, struct sip_pvt *p, int sipmetho
 		if ((ast_party_id_presentation(&p->owner->connected.id) & AST_PRES_RESTRICTION) == AST_PRES_ALLOWED) {
 			l = p->owner->connected.id.number.valid ? p->owner->connected.id.number.str : NULL;
 			n = p->owner->connected.id.name.valid ? p->owner->connected.id.name.str : NULL;
-		} else if (!ast_test_flag(&p->flags[0], SIP_SENDRPID)) {
-			/* if we are not sending RPID and user wants his callerid restricted */		
+		} else {
+			/* Even if we are using RPID, we shouldn't leak information in the From if the user wants
+			 * their callerid restricted */
 			l = CALLERID_UNKNOWN;
 			n = l;
 			d = FROMDOMAIN_INVALID;