- extended paillier-api to also include caller-suggested maximum supported homs

2 files changed, 8 insertions, 6 deletions

diff --git a/src/util/crypto_paillier.c b/src/util/crypto_paillier.c
index d47823905..6873d159f 100644
--- a/src/util/crypto_paillier.c
+++ b/src/util/crypto_paillier.c
@@ -92,12 +92,16 @@ GNUNET_CRYPTO_paillier_create (struct GNUNET_CRYPTO_PaillierPublicKey *public_ke
  *
  * @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;
diff --git a/src/util/test_crypto_paillier.c b/src/util/test_crypto_paillier.c
index b77100642..0dad500ba 100644
--- a/src/util/test_crypto_paillier.c
+++ b/src/util/test_crypto_paillier.c
@@ -45,7 +45,7 @@ test_crypto ()
 
   gcry_mpi_randomize (plaintext, GNUNET_CRYPTO_PAILLIER_BITS / 2, GCRY_WEAK_RANDOM);
 
-  GNUNET_CRYPTO_paillier_encrypt (&public_key, plaintext, &ciphertext);
+  GNUNET_CRYPTO_paillier_encrypt (&public_key, plaintext, 0, &ciphertext);
 
   GNUNET_CRYPTO_paillier_decrypt (&private_key, &public_key,
                                   &ciphertext, plaintext_result);
@@ -88,16 +88,14 @@ test_hom()
   gcry_mpi_mul_2exp(m2,m2,GNUNET_CRYPTO_PAILLIER_BITS-3);
   gcry_mpi_add(result,m1,m2);
 
-  if (1 != (ret = GNUNET_CRYPTO_paillier_encrypt (&public_key, m1, &c1))){
+  if (1 != (ret = GNUNET_CRYPTO_paillier_encrypt (&public_key, m1, 0, &c1))){
     printf ("GNUNET_CRYPTO_paillier_encrypt 1 failed, should return 1 allowed operation, got %d!\n", ret);
     return 1;
   }
-  if (1 != (ret = GNUNET_CRYPTO_paillier_encrypt (&public_key, m2, &c2))){
+  if (1 != (ret = GNUNET_CRYPTO_paillier_encrypt (&public_key, m2, 0, &c2))){
     printf ("GNUNET_CRYPTO_paillier_encrypt 2 failed, should return 1 allowed operation, got %d!\n", ret);
     return 1;
   }
-  
-  GNUNET_CRYPTO_paillier_encrypt (&public_key, m2, &c2);
 
   if (0 != (ret = GNUNET_CRYPTO_paillier_hom_add (&public_key, &c1,&c2, &c_result))){
     printf ("GNUNET_CRYPTO_paillier_hom_add failed, expected 0 remaining operations, got %d!\n", ret);