Fix compiler warnings from Clang 10 and GCC 9.

[meshlink] / src / sptps.c

diff --git a/src/sptps.c b/src/sptps.c
index 9017656a353802bd6deeb4e656407a1a9f05971a..be16d5ea2d71c8768b9aae623f2492bfc4363d96 100644 (file)
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -443,9 +443,7 @@ bool sptps_verify_datagram(sptps_t *s, const void *data, size_t len) {
        seqno = ntohl(seqno);
        // TODO: check whether seqno makes sense, to avoid CPU intensive decrypt
 
-       char buffer[len];
-       size_t outlen;
-       return chacha_poly1305_decrypt(s->incipher, seqno, (const char *)data + 4, len - 4, buffer, &outlen);
+       return chacha_poly1305_verify(s->incipher, seqno, (const char *)data + 4, len - 4);
 }
 
 // Receive incoming data, datagram version.
@@ -478,11 +476,20 @@ static bool sptps_receive_data_datagram(sptps_t *s, const void *vdata, size_t le
 
        // Decrypt
 
-       char buffer[len];
+       if(len > s->decrypted_buffer_len) {
+               s->decrypted_buffer_len *= 2;
+               char *new_buffer = realloc(s->decrypted_buffer, s->decrypted_buffer_len);
+
+               if(!new_buffer) {
+                       return error(s, errno, strerror(errno));
+               }
+
+               s->decrypted_buffer = new_buffer;
+       }
 
        size_t outlen;
 
-       if(!chacha_poly1305_decrypt(s->incipher, seqno, data + 4, len - 4, buffer, &outlen)) {
+       if(!chacha_poly1305_decrypt(s->incipher, seqno, data + 4, len - 4, s->decrypted_buffer, &outlen)) {
                return error(s, EIO, "Failed to decrypt and verify packet");
        }
 
@@ -526,20 +533,20 @@ static bool sptps_receive_data_datagram(sptps_t *s, const void *vdata, size_t le
        }
 
        // Append a NULL byte for safety.
-       buffer[len - 20] = 0;
+       s->decrypted_buffer[len - 20] = 0;
 
-       uint8_t type = buffer[0];
+       uint8_t type = s->decrypted_buffer[0];
 
        if(type < SPTPS_HANDSHAKE) {
                if(!s->instate) {
                        return error(s, EIO, "Application record received before handshake finished");
                }
 
-               if(!s->receive_record(s->handle, type, buffer + 1, len - 21)) {
+               if(!s->receive_record(s->handle, type, s->decrypted_buffer + 1, len - 21)) {
                        abort();
                }
        } else if(type == SPTPS_HANDSHAKE) {
-               if(!receive_handshake(s, buffer + 1, len - 21)) {
+               if(!receive_handshake(s, s->decrypted_buffer + 1, len - 21)) {
                        abort();
                }
        } else {
@@ -669,6 +676,12 @@ bool sptps_start(sptps_t *s, void *handle, bool initiator, bool datagram, ecdsa_
        s->mykey = mykey;
        s->hiskey = hiskey;
        s->replaywin = 32;
+       s->decrypted_buffer_len = 1024;
+       s->decrypted_buffer = malloc(s->decrypted_buffer_len);
+
+       if(!s->decrypted_buffer) {
+               return error(s, errno, strerror(errno));
+       }
 
        if(s->replaywin) {
                s->late = malloc(s->replaywin);
@@ -719,6 +732,8 @@ bool sptps_stop(sptps_t *s) {
        free(s->key);
        free(s->label);
        free(s->late);
+       memset(s->decrypted_buffer, 0, s->decrypted_buffer_len);
+       free(s->decrypted_buffer);
        memset(s, 0, sizeof(*s));
        return true;
 }