Allow running tinc without RSA keys.

This allows one to run tinc with only Ed25519 keys, forcing tinc to
always use the SPTPS protocol.

diff --git a/src/net_setup.c b/src/net_setup.c
index a7ed3a8995750b45ece4fe82f437fbd2bbe5bcf9..29f1212814234ff2b7db709d2eb97449d5e23b8c 100644 (file)
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -277,6 +277,8 @@ static bool read_rsa_private_key(void) {
        if(!fp) {
                logger(DEBUG_ALWAYS, LOG_ERR, "Error reading RSA private key file `%s': %s",
                           fname, strerror(errno));
+               if(errno == ENOENT)
+                       logger(DEBUG_ALWAYS, LOG_INFO, "Create an RSA keypair with `tinc -n %s generate-rsa-keys'.", netname ?: ".");
                free(fname);
                return false;
        }
@@ -780,8 +782,14 @@ static bool setup_myself(void) {
                        return false;
        }
 
-       if(!read_rsa_private_key())
-               return false;
+       if(!read_rsa_private_key()) {
+               if(experimental) {
+                       logger(DEBUG_ALWAYS, LOG_WARNING, "Support for legacy protocol disabled.");
+               } else {
+                       logger(DEBUG_ALWAYS, LOG_ERR, "No private keys available, cannot start tinc!");
+                       return false;
+               }
+       }
 
        /* Ensure myport is numeric */
 

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index 47c248db5ede5d47559164ab8f7b45657d71f8e2..cd39f28debee0b2d2d7090a4f0cdfedead95ab8e 100644 (file)
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -412,6 +412,11 @@ bool id_h(connection_t *c, const char *request) {
 }
 
 bool send_metakey(connection_t *c) {
+       if(!myself->connection->rsa) {
+               logger(DEBUG_CONNECTIONS, LOG_ERR, "Peer %s (%s) uses legacy protocol which we don't support", c->name, c->hostname);
+               return false;
+       }
+
        if(!read_rsa_public_key(c))
                return false;
 
@@ -478,6 +483,9 @@ bool send_metakey(connection_t *c) {
 }
 
 bool metakey_h(connection_t *c, const char *request) {
+       if(!myself->connection->rsa)
+               return false;
+
        char hexkey[MAX_STRING_SIZE];
        int cipher, digest, maclength, compression;
        const size_t len = rsa_size(myself->connection->rsa);
@@ -560,6 +568,9 @@ bool send_challenge(connection_t *c) {
 }
 
 bool challenge_h(connection_t *c, const char *request) {
+       if(!myself->connection->rsa)
+               return false;
+
        char buffer[MAX_STRING_SIZE];
        const size_t len = rsa_size(myself->connection->rsa);
        size_t digestlen = digest_length(c->indigest);