Fix datagram SPTPS.

[tinc] / src / sptps.c

diff --git a/src/sptps.c b/src/sptps.c
index fe97844..8242cad 100644 (file)
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -447,8 +447,6 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
        memcpy(buffer, &netlen, 2);
        memcpy(buffer + 2, data, len);
 
-       memcpy(&seqno, buffer + 2, 4);
-
        if(!digest_verify(&s->indigest, buffer, len - 14, buffer + len - 14))
                return error(s, EIO, "Invalid HMAC");
 
@@ -492,6 +490,7 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
                s->received++;
 
        // Decrypt.
+       memcpy(&seqno, buffer + 2, 4);
        cipher_set_counter(&s->incipher, &seqno, sizeof seqno);
        if(!cipher_counter_xor(&s->incipher, buffer + 6, len - 4, buffer + 6))
                return false;