Handle SPTPS datagrams in try_mac().

[tinc] / src / sptps.c

diff --git a/src/sptps.c b/src/sptps.c
index bdbfb89..12c6c7f 100644 (file)
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -78,10 +78,10 @@ static bool send_record_priv_datagram(sptps_t *s, uint8_t type, const char *data
                if(!digest_create(&s->outdigest, buffer, len + 7UL, buffer + 7UL + len))
                        return false;
 
-               return s->send_data(s->handle, buffer + 2, len + 21UL);
+               return s->send_data(s->handle, type, buffer + 2, len + 21UL);
        } else {
                // Otherwise send as plaintext
-               return s->send_data(s->handle, buffer + 2, len + 5UL);
+               return s->send_data(s->handle, type, buffer + 2, len + 5UL);
        }
 }
 // Send a record (private version, accepts all record types, handles encryption and authentication).
@@ -110,10 +110,10 @@ static bool send_record_priv(sptps_t *s, uint8_t type, const char *data, uint16_
                if(!digest_create(&s->outdigest, buffer, len + 7UL, buffer + 7UL + len))
                        return false;
 
-               return s->send_data(s->handle, buffer + 4, len + 19UL);
+               return s->send_data(s->handle, type, buffer + 4, len + 19UL);
        } else {
                // Otherwise send as plaintext
-               return s->send_data(s->handle, buffer + 4, len + 3UL);
+               return s->send_data(s->handle, type, buffer + 4, len + 3UL);
        }
 }
 
@@ -376,6 +376,20 @@ static bool receive_handshake(sptps_t *s, const char *data, uint16_t len) {
        }
 }
 
+// Check datagram for valid HMAC
+bool sptps_verify_datagram(sptps_t *s, const char *data, size_t len) {
+       if(!s->instate || len < 21)
+               return false;
+
+       char buffer[len + 23];
+       uint16_t netlen = htons(len - 21);
+
+       memcpy(buffer, &netlen, 2);
+       memcpy(buffer + 2, data, len);
+
+       return digest_verify(&s->indigest, buffer, len - 14, buffer + len - 14);
+}
+
 // Receive incoming data, datagram version.
 static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len) {
        if(len < (s->instate ? 21 : 5))
@@ -438,6 +452,9 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
                        return error(s, EIO, "Application record received before handshake finished");
                if(!s->receive_record(s->handle, type, buffer + 7, len - 21))
                        return false;
+       } else if(type == SPTPS_HANDSHAKE) {
+               if(!receive_handshake(s, buffer + 7, len - 21))
+                       return false;
        } else {
                return error(s, EIO, "Invalid record type");
        }
@@ -576,9 +593,14 @@ bool sptps_stop(sptps_t *s) {
        // Clean up any resources.
        ecdh_free(&s->ecdh);
        free(s->inbuf);
+       s->inbuf = NULL;
        free(s->mykex);
+       s->mykex = NULL;
        free(s->hiskex);
+       s->hiskex = NULL;
        free(s->key);
+       s->key = NULL;
        free(s->label);
+       s->label = NULL;
        return true;
 }