#include "prf.h"
#include "sptps.h"
-unsigned int sptps_replaywin = 32;
-
/*
Nonce MUST be exchanged first (done)
Signatures MUST be done over both nonces, to guarantee the signature is fresh
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.
// 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");
}
}
// 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 {
s->datagram = datagram;
s->mykey = mykey;
s->hiskey = hiskey;
- s->replaywin = sptps_replaywin;
+ 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);
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;
}