/**
- * Encrypt a block with the public key of another
- * host that uses the same cyper.
+ * Encrypt a block with a symmetric session key.
*
* @param block the block to encrypt
- * @param len the size of the @a block
+ * @param size the size of the @a block
* @param sessionkey the key used to encrypt
- * @param iv the initialization vector to use, use INITVALUE
- * for streams.
+ * @param iv the initialization vector to use, use INITVALUE for streams
* @param result the output parameter in which to store the encrypted result
- * @returns the size of the encrypted block, -1 for errors
+ * can be the same or overlap with @c block
+ * @returns the size of the encrypted block, -1 for errors.
+ * Due to the use of CFB and therefore an effective stream cipher,
+ * this size should be the same as @c len.
*/
ssize_t
GNUNET_CRYPTO_symmetric_encrypt (const void *block,
- size_t len,
+ size_t size,
const struct GNUNET_CRYPTO_SymmetricSessionKey *sessionkey,
const struct GNUNET_CRYPTO_SymmetricInitializationVector *iv,
void *result)
{
gcry_cipher_hd_t handle;
- char tmp[len];
+ char tmp[size];
if (GNUNET_OK != setup_cipher_aes (&handle, sessionkey, iv))
return -1;
- GNUNET_assert (0 == gcry_cipher_encrypt (handle, tmp, len, block, len));
+ GNUNET_assert (0 == gcry_cipher_encrypt (handle, tmp, size, block, size));
gcry_cipher_close (handle);
if (GNUNET_OK != setup_cipher_twofish (&handle, sessionkey, iv))
return -1;
- GNUNET_assert (0 == gcry_cipher_encrypt (handle, result, len, tmp, len));
+ GNUNET_assert (0 == gcry_cipher_encrypt (handle, result, size, tmp, size));
gcry_cipher_close (handle);
memset (tmp, 0, sizeof (tmp));
- return len;
+ return size;
}
/**
- * Decrypt a given block with the sessionkey.
+ * Decrypt a given block with the session key.
*
* @param block the data to decrypt, encoded as returned by encrypt
* @param size the size of the @a block to decrypt
* @param sessionkey the key used to decrypt
- * @param iv the initialization vector to use, use INITVALUE
- * for streams.
+ * @param iv the initialization vector to use, use INITVALUE for streams
* @param result address to store the result at
- * @return -1 on failure, size of decrypted block on success
+ * can be the same or overlap with @c block
+ * @return -1 on failure, size of decrypted block on success.
+ * Due to the use of CFB and therefore an effective stream cipher,
+ * this size should be the same as @c size.
*/
ssize_t
GNUNET_CRYPTO_symmetric_decrypt (const void *block, size_t size,