}
-/**
- * Encrypts an element using the paillier crypto system
- *
- * @param c ciphertext (output)
- * @param m plaintext
- * @param g the public base
- * @param n the module from which which r is chosen (Z*_n)
- * @param n_square the module for encryption, for performance reasons.
- */
-static void
-encrypt_element (gcry_mpi_t c, gcry_mpi_t m, gcry_mpi_t g, gcry_mpi_t n, gcry_mpi_t n_square)
-{
- gcry_mpi_t tmp;
-
- GNUNET_assert (tmp = gcry_mpi_new (0));
-
- while (0 >= gcry_mpi_cmp_ui (tmp, 1))
- {
- gcry_mpi_randomize (tmp, KEYBITS / 3, GCRY_WEAK_RANDOM);
- // r must be 1 < r < n
- }
-
- gcry_mpi_powm (c, g, m, n_square);
- gcry_mpi_powm (tmp, tmp, n, n_square);
- gcry_mpi_mulm (c, tmp, c, n_square);
-
- gcry_mpi_release (tmp);
-}
-
-
/**
* decrypts an element using the paillier crypto system
*
uint32_t count;
gcry_mpi_t * rand = NULL;
gcry_mpi_t * r = NULL;
+ struct GNUNET_CRYPTO_PaillierCiphertext * R;
gcry_mpi_t * r_prime = NULL;
+ struct GNUNET_CRYPTO_PaillierCiphertext * R_prime;
gcry_mpi_t * b;
gcry_mpi_t * a_pi;
gcry_mpi_t * a_pi_prime;
gcry_mpi_t * rand_pi;
gcry_mpi_t * rand_pi_prime;
gcry_mpi_t s = NULL;
+ struct GNUNET_CRYPTO_PaillierCiphertext * S;
gcry_mpi_t s_prime = NULL;
- gcry_mpi_t remote_n = NULL;
- gcry_mpi_t remote_nsquare;
- gcry_mpi_t remote_g = NULL;
- gcry_sexp_t tmp_exp;
+ struct GNUNET_CRYPTO_PaillierCiphertext * S_prime;
+
uint32_t value;
count = request->used;
response->vector = NULL;
q = NULL;
p = NULL;
- tmp_exp = gcry_sexp_find_token (request->remote_pubkey, "n", 0);
- if (!tmp_exp)
- {
- GNUNET_break_op (0);
- gcry_sexp_release (request->remote_pubkey);
- request->remote_pubkey = NULL;
- goto except;
- }
- remote_n = gcry_sexp_nth_mpi (tmp_exp, 1, GCRYMPI_FMT_USG);
- if (!remote_n)
- {
- GNUNET_break (0);
- gcry_sexp_release (tmp_exp);
- goto except;
- }
- remote_nsquare = gcry_mpi_new (KEYBITS + 1);
- gcry_mpi_mul (remote_nsquare, remote_n, remote_n);
- gcry_sexp_release (tmp_exp);
- tmp_exp = gcry_sexp_find_token (request->remote_pubkey, "g", 0);
- gcry_sexp_release (request->remote_pubkey);
- request->remote_pubkey = NULL;
- if (!tmp_exp)
- {
- GNUNET_break_op (0);
- gcry_mpi_release (remote_n);
- goto except;
- }
- remote_g = gcry_sexp_nth_mpi (tmp_exp, 1, GCRYMPI_FMT_USG);
- if (!remote_g)
- {
- GNUNET_break (0);
- gcry_mpi_release (remote_n);
- gcry_sexp_release (tmp_exp);
- goto except;
- }
- gcry_sexp_release (tmp_exp);
// generate r, p and q
rand = initialize_mpi_vector (count);
memcpy (b_pi, b, sizeof (gcry_mpi_t) * count);
memcpy (rand_pi, rand, sizeof (gcry_mpi_t) * count);
memcpy (rand_pi_prime, rand, sizeof (gcry_mpi_t) * count);
+
+ //todo get API-cryptoblocks, instead of MPI values
// generate p and q permutations for a, b and r
+ // TODO: APIify
GNUNET_assert (permute_vector (a_pi, p, count));
GNUNET_assert (permute_vector (b_pi, p, count));
GNUNET_assert (permute_vector (rand_pi, p, count));
// E(S - r_pi - b_pi)
gcry_mpi_sub (r[i], my_offset, rand_pi[i]);
gcry_mpi_sub (r[i], r[i], b_pi[i]);
- encrypt_element (r[i], r[i], remote_g, remote_n, remote_nsquare);
-
+ GNUNET_CRYPTO_paillier_encrypt (&request->remote_pubkey,
+ r[i],
+ &R[i]);
+
// E(S - r_pi - b_pi) * E(S + a_pi) == E(2*S + a - r - b)
- gcry_mpi_mulm (r[i], r[i], a_pi[i], remote_nsquare);
+ GNUNET_CRYPTO_paillier_hom_add (&request->remote_pubkey,
+ &R[i],
+ &A_pi[i],
+ &R[i]);
}
GNUNET_free (a_pi);
GNUNET_free (b_pi);
{
// E(S - r_qi)
gcry_mpi_sub (r_prime[i], my_offset, rand_pi_prime[i]);
- encrypt_element (r_prime[i], r_prime[i], remote_g, remote_n, remote_nsquare);
+ GNUNET_CRYPTO_paillier_encrypt (&request->remote_pubkey,
+ r_prime[i],
+ &R_prime[i]);
// E(S - r_qi) * E(S + a_qi) == E(2*S + a_qi - r_qi)
- gcry_mpi_mulm (r_prime[i], r_prime[i], a_pi_prime[i], remote_nsquare);
+ GNUNET_CRYPTO_paillier_hom_add (&request->remote_pubkey,
+ &R_prime[i],
+ &A_pi_prime[i],
+ &R_prime[i]);
}
GNUNET_free (a_pi_prime);
GNUNET_free (rand_pi_prime);
// Calculate S' = E(SUM( r_i^2 ))
s_prime = compute_square_sum (rand, count);
- encrypt_element (s_prime, s_prime, remote_g, remote_n, remote_nsquare);
+ GNUNET_CRYPTO_paillier_encrypt (&request->remote_pubkey,
+ s_prime,
+ &S_prime);
// Calculate S = E(SUM( (r_i + b_i)^2 ))
for (i = 0; i < count; i++) {
gcry_mpi_add (rand[i], rand[i], b[i]);
}
s = compute_square_sum (rand, count);
- encrypt_element (s, s, remote_g, remote_n, remote_nsquare);
- gcry_mpi_release (remote_n);
- gcry_mpi_release (remote_g);
- gcry_mpi_release (remote_nsquare);
+ GNUNET_CRYPTO_paillier_encrypt (&request->remote_pubkey,
+ s[i],
+ &S);
// release r and tmp
for (i = 0; i < count; i++)
gcry_mpi_release (rand[i]);
// copy the r[], r_prime[], S and Stick into a new message, prepare_service_response frees these
- if (GNUNET_YES != prepare_service_response (s, s_prime, request))
+ if (GNUNET_YES != prepare_service_response (S, S_prime, request))
GNUNET_log (GNUNET_ERROR_TYPE_INFO, _ ("Failed to communicate with `%s', scalar product calculation aborted.\n"),
GNUNET_i2s (&request->peer));
else