Libtomcrypt integration is broken

SQLCipher Issues
1

There is a bug with the way the fortuna rng is used in the libtomcrypt integration.

sqlcipher_ltc_activate initialises the global prng state when ltc_init is zero. That is, once only.

After a call to sqlcipher_ltc_deactivate where the ref reaches zero, the state is closed and cleared.

Subsequent calls to sqlcipher_ltc_activate will not re-initialise the prng state, resulting in a segfault in sqlcipher_ltc_random on the call to fortuna_read.

As a workaround, I pulled the call to fortuna_start out of the ltc_init check, and into one where it checks the ref count. eg

if(ltc_ref_count == 0) {
  if(fortuna_start(&prng) != CRYPT_OK) {
    return SQLITE_ERROR;
  }
}

That stops the segfaults for me.

I can only assume no one else is using libtomcrypt :slight_smile: