Stop logging link auth warnings on Single Onion Services and Tor2web

Instead, log a protocol warning when single onion services or
Tor2web clients fail to authenticate direct connections to relays.

Fixes bug 26924; bugfix on 0.2.9.1-alpha.

changes/bug26924

@@ -0,0 +1,4 @@
+  o Minor bugfixes (single onion services, Tor2web):
+    - Log a protocol warning when single onion services or Tor2web clients
+      fail to authenticate direct connections to relays.
+      Fixes bug 26924; bugfix on 0.2.9.1-alpha.

src/or/connection_or.c

@@ -47,6 +47,7 @@
 #include "nodelist.h"
 #include "reasons.h"
 #include "relay.h"
+#include "rendcommon.h"
 #include "rephist.h"
 #include "router.h"
 #include "routerlist.h"
@@ -1628,10 +1629,13 @@ connection_or_client_learned_peer_id(or_connection_t *conn,
                                                    conn->identity_digest);
     const int is_authority_fingerprint = router_digest_is_trusted_dir(
                                                    conn->identity_digest);
+    const int non_anonymous_mode = rend_non_anonymous_mode_enabled(options);
     int severity;
     const char *extra_log = "";
 
-    if (server_mode(options)) {
+    /* Relays, Single Onion Services, and Tor2web make direct connections using
+     * untrusted authentication keys. */
+    if (server_mode(options) || non_anonymous_mode) {
       severity = LOG_PROTOCOL_WARN;
     } else {
       if (using_hardcoded_fingerprints) {