*
* @param public_key Public key to use.
* @param m Plaintext to encrypt.
+ * @param desired_ops How many homomorphic ops the caller intends to use
* @param[out] ciphertext Encrytion of @a plaintext with @a public_key.
- * @return guaranteed number of supported homomorphic operations, can be zero
+ * @return guaranteed number of supported homomorphic operations >= 1,
+ * or desired_ops, in case that is lower,
+ * or -1 if less than one homomorphic operation is possible
*/
int
GNUNET_CRYPTO_paillier_encrypt (const struct GNUNET_CRYPTO_PaillierPublicKey *public_key,
const gcry_mpi_t m,
+ int desired_ops,
struct GNUNET_CRYPTO_PaillierCiphertext *ciphertext)
{
int possible_opts;
gcry_mpi_t n_square;
gcry_mpi_t r;
- gcry_mpi_t g;
gcry_mpi_t c;
gcry_mpi_t n;
gcry_mpi_t tmp1;
if (possible_opts < 1)
possible_opts = 0;
+ //soft-cap by caller
+ possible_opts = (desired_ops < possible_opts)? desired_ops : possible_opts;
+
ciphertext->remaining_ops = htonl (possible_opts);
GNUNET_assert (0 != (n_square = gcry_mpi_new (0)));
GNUNET_assert (0 != (r = gcry_mpi_new (0)));
- GNUNET_assert (0 != (g = gcry_mpi_new (0)));
GNUNET_assert (0 != (c = gcry_mpi_new (0)));
GNUNET_CRYPTO_mpi_scan_unsigned (&n, public_key, sizeof (struct GNUNET_CRYPTO_PaillierPublicKey));
c);
gcry_mpi_release (n_square);
+ gcry_mpi_release (n);
gcry_mpi_release (r);
gcry_mpi_release (c);