test_brandt nearly done

1 files changed, 161 insertions, 42 deletions

diff --git a/crypto.c b/crypto.c
index edd51ad..eb7e944 100644
--- a/crypto.c
+++ b/crypto.c
@@ -455,18 +455,11 @@ gcry_mpi_point_t **
 smc_init2 (uint16_t size1, uint16_t size2)
 {
 	gcry_mpi_point_t **ret;
-	gcry_mpi_point_t *data;
 
-	if (NULL == (ret = calloc (size1, sizeof (*ret) + size2 * sizeof (**ret))))
-	{
-		weprintf ("could not alloc memory for 2 dimensional point array");
-		return NULL;
-	}
+	ret = GNUNET_new_array_2d (size1, size2, gcry_mpi_point_t);
 
-	data = (gcry_mpi_point_t *)&ret[size1];
 	for (uint16_t i = 0; i < size1; i++)
 	{
-		ret[i] = &data[i * size2];
 		for (uint16_t j = 0; j < size2; j++)
 		{
 			if (NULL == (ret[i][j] = gcry_mpi_point_new (0)))
@@ -523,25 +516,13 @@ gcry_mpi_point_t ***
 smc_init3 (uint16_t size1, uint16_t size2, uint16_t size3)
 {
 	gcry_mpi_point_t ***ret;
-	gcry_mpi_point_t **layer1;
-	gcry_mpi_point_t *layer2;
 
-	if (NULL == (ret = calloc (size1, sizeof (*ret) +
-	                           size2 * sizeof (**ret) +
-	                           size2 * size3 * sizeof (***ret))))
-	{
-		weprintf ("could not alloc memory for 3 dimensional point array");
-		return NULL;
-	}
+	ret = GNUNET_new_array_3d (size1, size2, size3, gcry_mpi_point_t);
 
-	layer1 = (gcry_mpi_point_t **)&ret[size1];
-	layer2 = (gcry_mpi_point_t *)&layer1[size1 * size2];
 	for (uint16_t i = 0; i < size1; i++)
 	{
-		ret[i] = &layer1[i * size2];
 		for (uint16_t j = 0; j < size2; j++)
 		{
-			layer1[i * size2 + j] = &layer2[(i * size2 + j) * size3];
 			for (uint16_t k = 0; k < size3; k++)
 			{
 				if (NULL == (ret[i][j][k] = gcry_mpi_point_new (0)))
@@ -1476,6 +1457,12 @@ fp_priv_prep_decryption (struct BRANDT_Auction *ad)
 	ad->phi3 = smc_init3 (ad->n, ad->n, ad->k);
 	brandt_assert (ad->phi3);
 
+	ad->phiproofs3 = GNUNET_new_array_3d (ad->n,
+	                                      ad->n,
+	                                      ad->k,
+	                                      struct proof_2dle);
+	brandt_assert (ad->phiproofs3);
+
 	for (uint16_t i = 0; i < ad->n; i++)
 	{
 		for (uint16_t j = 0; j < ad->k; j++)
@@ -1494,17 +1481,8 @@ fp_priv_prep_decryption (struct BRANDT_Auction *ad)
 }
 
 
-/**
- * fp_priv_decrypt_outcome decrypts the own shares of the outcome and packs them
- * into a message buffer together with proofs of correctnes.
- *
- * @param[in] ad Pointer to the BRANDT_Auction struct to operate on
- * @param[out] buflen Size of the returned message buffer in bytes
- * @return A buffer containing the own share of the decrypted outcome
- * which needs to be broadcast
- */
-unsigned char *
-fp_priv_decrypt_outcome (struct BRANDT_Auction *ad, size_t *buflen)
+static unsigned char *
+fp_priv_decrypt_outcome_seller (struct BRANDT_Auction *ad, size_t *buflen)
 {
 	unsigned char     *ret;
 	unsigned char     *cur;
@@ -1513,7 +1491,51 @@ fp_priv_decrypt_outcome (struct BRANDT_Auction *ad, size_t *buflen)
 	struct ec_mpi     *phi;
 	struct proof_2dle *proof2;
 
-	brandt_assert (ad && buflen);
+	*buflen = (sizeof (*head) +
+	           (ad->n - 1) * ad->n * ad->k * (sizeof (*phi) +
+	                                          sizeof (*proof2)));
+	ret = GNUNET_new_array (*buflen, unsigned char);
+
+	head = (struct msg_head *)ret;
+	head->prot_version = htonl (0);
+	head->msg_type = htonl (msg_decrypt);
+	cur = ret + sizeof (*head);
+
+	for (uint16_t h = 0; h < ad->n; h++)
+	{
+		for (uint16_t i = 0; i < ad->n; i++)
+		{
+			/* don't reveal outcome to losing bidders */
+			if (h == i)
+				continue;
+
+			for (uint16_t j = 0; j < ad->k; j++)
+			{
+				phi = (struct ec_mpi *)cur;
+				proof2 = (struct proof_2dle *)(cur + sizeof (*phi));
+
+				ec_point_serialize (phi, ad->phi3[h][i][j]);
+				memcpy (proof2, &ad->phiproofs3[h][i][j], sizeof (*proof2));
+
+				cur += sizeof (*phi) + sizeof (*proof2);
+			}
+		}
+	}
+
+	gcry_mpi_point_release (tmp);
+	return ret;
+}
+
+
+static unsigned char *
+fp_priv_decrypt_outcome_bidder (struct BRANDT_Auction *ad, size_t *buflen)
+{
+	unsigned char     *ret;
+	unsigned char     *cur;
+	struct msg_head   *head;
+	gcry_mpi_point_t  tmp = gcry_mpi_point_new (0);
+	struct ec_mpi     *phi;
+	struct proof_2dle *proof2;
 
 	*buflen = (sizeof (*head) +
 	           ad->n * ad->k * (sizeof (*phi) + sizeof (*proof2)));
@@ -1552,22 +1574,42 @@ fp_priv_decrypt_outcome (struct BRANDT_Auction *ad, size_t *buflen)
 }
 
 
-int
-fp_priv_recv_decryption (struct BRANDT_Auction *ad,
-                         const unsigned char   *buf,
-                         size_t                buflen,
-                         uint16_t              sender)
+/**
+ * fp_priv_decrypt_outcome decrypts the own shares of the outcome and packs them
+ * into a message buffer together with proofs of correctnes. When this is called
+ * as the seller it will not decrypt anything, but just create the message
+ * buffer from all received decryption shares to broadcast back to all bidders.
+ *
+ * @param[in] ad Pointer to the BRANDT_Auction struct to operate on
+ * @param[out] buflen Size of the returned message buffer in bytes
+ * @return A buffer containing the share of the decrypted outcome
+ * which needs to be broadcast
+ */
+unsigned char *
+fp_priv_decrypt_outcome (struct BRANDT_Auction *ad, size_t *buflen)
+{
+	brandt_assert (ad && buflen);
+	if (ad->seller_mode)
+		return fp_priv_decrypt_outcome_seller (ad, buflen);
+	else
+		return fp_priv_decrypt_outcome_bidder (ad, buflen);
+}
+
+
+static int
+fp_priv_recv_decryption_seller (struct BRANDT_Auction *ad,
+                                const unsigned char   *buf,
+                                size_t                buflen,
+                                uint16_t              sender)
 {
 	int                 ret = 0;
 	const unsigned char *cur = buf;
 	struct proof_2dle   *proof2;
 	gcry_mpi_point_t    phi = gcry_mpi_point_new (0);
 
-	brandt_assert (ad && buf);
-
 	if (buflen != (ad->n * ad->k * (sizeof (struct ec_mpi) + sizeof (*proof2))))
 	{
-		weprintf ("wrong size of received outcome decryption");
+		weprintf ("wrong size of received outcome decryption from bidder");
 		goto quit;
 	}
 
@@ -1583,9 +1625,13 @@ fp_priv_recv_decryption (struct BRANDT_Auction *ad,
 			                        ec_gen,
 			                        proof2))
 			{
-				weprintf ("wrong zkp2 for phi, y received");
+				weprintf ("wrong zkp2 for phi, y received from bidder");
 				goto quit;
 			}
+
+			/* store proof. we need to rebroadcast it to the other bidders */
+			memcpy (&ad->phiproofs3[sender][i][j], proof2, sizeof (*proof2));
+
 			ec_point_copy (ad->phi3[sender][i][j], phi);
 			cur += sizeof (struct ec_mpi) + sizeof (*proof2);
 		}
@@ -1598,6 +1644,79 @@ quit:
 }
 
 
+static int
+fp_priv_recv_decryption_bidder (struct BRANDT_Auction *ad,
+                                const unsigned char   *buf,
+                                size_t                buflen,
+                                uint16_t              sender)
+{
+	int                 ret = 0;
+	const unsigned char *cur = buf;
+	struct proof_2dle   *proof2;
+	gcry_mpi_point_t    phi = gcry_mpi_point_new (0);
+
+	if (buflen != ((ad->n - 1) * ad->n * ad->k * (sizeof (struct ec_mpi) +
+	                                              sizeof (*proof2))))
+	{
+		weprintf ("wrong size of received outcome decryption from seller");
+		goto quit;
+	}
+
+	for (uint16_t h = 0; h < ad->n; h++)
+	{
+		for (uint16_t i = 0; i < ad->n; i++)
+		{
+			/* those combinations are not sent by the seller */
+			if (h == i)
+				continue;
+
+			/* we already have our own phi values */
+			if (h == ad->i)
+			{
+				cur += ad->k * (sizeof (struct ec_mpi) + sizeof (*proof2));
+				continue;
+			}
+
+			for (uint16_t j = 0; j < ad->k; j++)
+			{
+				ec_point_parse (phi, (struct ec_mpi *)cur);
+				proof2 = (struct proof_2dle *)(cur + sizeof (struct ec_mpi));
+				if (smc_zkp_2dle_check (phi,
+										ad->y[h],
+										ad->phi3[h][i][j],
+										ec_gen,
+										proof2))
+				{
+					weprintf ("wrong zkp2 for phi, y received from seller");
+					goto quit;
+				}
+				ec_point_copy (ad->phi3[h][i][j], phi);
+				cur += sizeof (struct ec_mpi) + sizeof (*proof2);
+			}
+		}
+	}
+
+	ret = 1;
+quit:
+	gcry_mpi_point_release (phi);
+	return ret;
+}
+
+
+int
+fp_priv_recv_decryption (struct BRANDT_Auction *ad,
+                         const unsigned char   *buf,
+                         size_t                buflen,
+                         uint16_t              sender)
+{
+	brandt_assert (ad && buf);
+	if (ad->seller_mode)
+		return fp_priv_recv_decryption_seller (ad, buf, buflen, sender);
+	else
+		return fp_priv_recv_decryption_bidder (ad, buf, buflen, sender);
+}
+
+
 struct BRANDT_Result *fp_priv_determine_outcome (struct BRANDT_Auction *ad,
                                                  uint16_t              *len)
 {