Better log messages when we already know the peer's key during an upgrade.

[tinc] / src / protocol_auth.c

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index 73a591e..84aece0 100644 (file)
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -381,11 +381,11 @@ bool id_h(connection_t *c, const char *request) {
                if(experimental)
                        read_ecdsa_public_key(c);
                        /* Ignore failures if no key known yet */
-       } else {
-               if(c->protocol_minor && !ecdsa_active(c->ecdsa))
-                       c->protocol_minor = 1;
        }
 
+       if(c->protocol_minor && !ecdsa_active(c->ecdsa))
+               c->protocol_minor = 1;
+
        /* Forbid version rollback for nodes whose Ed25519 key we know */
 
        if(ecdsa_active(c->ecdsa) && c->protocol_minor < 2) {
@@ -726,7 +726,21 @@ static bool upgrade_h(connection_t *c, const char *request) {
        }
 
        if(ecdsa_active(c->ecdsa) || read_ecdsa_public_key(c)) {
-               logger(DEBUG_ALWAYS, LOG_INFO, "Already have Ed25519 public key from %s (%s), not upgrading.", c->name, c->hostname);
+               char *knownkey = ecdsa_get_base64_public_key(c->ecdsa);
+               bool different = strcmp(knownkey, pubkey);
+               free(knownkey);
+               if(different) {
+                       logger(DEBUG_ALWAYS, LOG_ERR, "Already have an Ed25519 public key from %s (%s) which is different from the one presented now!", c->name, c->hostname);
+                       return false;
+               }
+               logger(DEBUG_ALWAYS, LOG_INFO, "Already have Ed25519 public key from %s (%s), ignoring.", c->name, c->hostname);
+               c->allow_request = TERMREQ;
+               return send_termreq(c);
+       }
+
+       c->ecdsa = ecdsa_set_base64_public_key(pubkey);
+       if(!c->ecdsa) {
+               logger(DEBUG_ALWAYS, LOG_INFO, "Got bad Ed25519 public key from %s (%s), not upgrading.", c->name, c->hostname);
                return false;
        }