add key-share generation

crypto.c

@@ -425,6 +425,20 @@ smc_compute_pkey (struct AuctionData *ad)
 }
 
 
+void
+smc_gen_keyshare (struct AuctionData *ad)
+{
+	uint16_t i;
+
+	ad->y = calloc(ad->n, sizeof(*ad->y));
+	for (i = 0; i < ad->n; i++)
+		ad->y[0] = gcry_mpi_point_new (0);
+
+	ad->x = gcry_mpi_new (0);
+	ec_keypair_create (ad->y[ad->i], ad->x);
+}
+
+
 /**
  * smc_zkp_dl
  *

crypto.h

@@ -25,6 +25,8 @@
 #include <gcrypt.h>
 #include <stdint.h>
 
+#include "internals.h"
+
 void brandt_crypto_init ();
 
 
@@ -64,8 +66,6 @@ void ec_keypair_create_base (gcry_mpi_point_t       pkey,
                              const gcry_mpi_point_t base);
 
 
-
-
 /* --- Zero knowledge proofs --- */
 
 void smc_zkp_dl (const gcry_mpi_point_t v,
@@ -124,4 +124,9 @@ int smc_zkp_0og_check (const gcry_mpi_point_t alpha,
                        const gcry_mpi_t       r1,
                        const gcry_mpi_t       r2);
 
+/* --- Protocol implementation --- */
+
+void smc_gen_keyshare (struct AuctionData *ad);
+void smc_compute_pkey (struct AuctionData *ad);
+
 #endif /* ifndef _BRANDT_CRYPTO_H */