wallet2: fix decrypting a bit too much in authenticated mode

This commit is contained in:
moneromooo-monero 2016-11-17 20:21:11 +00:00
parent dbf2ab56c5
commit e6264a2c35
No known key found for this signature in database
GPG key ID: 686F07454D6CEFC3

View file

@ -4889,14 +4889,15 @@ std::string wallet2::encrypt_with_view_secret_key(const std::string &plaintext,
//----------------------------------------------------------------------------------------------------
std::string wallet2::decrypt(const std::string &ciphertext, const crypto::secret_key &skey, bool authenticated) const
{
THROW_WALLET_EXCEPTION_IF(ciphertext.size() < sizeof(chacha8_iv),
error::wallet_internal_error, "key_image generated ephemeral public key not matched with output_key");
const size_t prefix_size = sizeof(chacha8_iv) + (authenticated ? sizeof(crypto::signature) : 0);
THROW_WALLET_EXCEPTION_IF(ciphertext.size() < prefix_size,
error::wallet_internal_error, "Unexpected ciphertext size");
crypto::chacha8_key key;
crypto::generate_chacha8_key(&skey, sizeof(skey), key);
const crypto::chacha8_iv &iv = *(const crypto::chacha8_iv*)&ciphertext[0];
std::string plaintext;
plaintext.resize(ciphertext.size() - sizeof(iv) - (authenticated ? sizeof(crypto::signature) : 0));
plaintext.resize(ciphertext.size() - prefix_size);
if (authenticated)
{
crypto::hash hash;
@ -4907,7 +4908,7 @@ std::string wallet2::decrypt(const std::string &ciphertext, const crypto::secret
THROW_WALLET_EXCEPTION_IF(!crypto::check_signature(hash, pkey, signature),
error::wallet_internal_error, "Failed to authenticate criphertext");
}
crypto::chacha8(ciphertext.data() + sizeof(iv), ciphertext.size() - sizeof(iv), key, iv, &plaintext[0]);
crypto::chacha8(ciphertext.data() + sizeof(iv), ciphertext.size() - prefix_size, key, iv, &plaintext[0]);
return std::move(plaintext);
}
//----------------------------------------------------------------------------------------------------