merge smc into crypto module. add 2dim array helpers

7 files changed, 539 insertions, 560 deletions

diff --git a/Makefile.am b/Makefile.am
index 76820c6..0f9dd23 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,8 +7,7 @@ lib_LTLIBRARIES = \
 libbrandt_la_SOURCES = \
   brandt.c \
   crypto.c \
-  util.c \
-  smc.c
+  util.c
 
 libbrandt_la_LIBADD = \
   -lgcrypt -lgpg-error
diff --git a/configure.ac b/configure.ac
index 14b04b4..7045a2f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -6,7 +6,7 @@ AC_INIT([libbrandt], [0.1], [teichm@net.in.tum.de])
 
 AM_INIT_AUTOMAKE([1.15])
 
-AC_CONFIG_SRCDIR([smc.c])
+AC_CONFIG_SRCDIR([brandt.c])
 #AC_CONFIG_HEADERS([config.h])
 
 # Checks for programs.
diff --git a/crypto.c b/crypto.c
index 31ba396..0c2597d 100644
--- a/crypto.c
+++ b/crypto.c
@@ -19,25 +19,22 @@
  * @brief Implementation of the crypto primitives.
  */
 
+
 #include <arpa/inet.h>
+#include <gcrypt.h>
 
 #include "crypto.h"
+#include "internals.h"
 #include "util.h"
 
 #define CURVE "Ed25519"
 
-struct brandt_ec_skey {
-	unsigned char d[256 / 8];
-};
 
-struct brandt_ec_pkey {
-	unsigned char q_y[256 / 8];
-};
+static gcry_ctx_t       ec_ctx;
+static gcry_mpi_point_t ec_gen;
+static gcry_mpi_point_t ec_zero;
+static gcry_mpi_t       ec_n;
 
-gcry_ctx_t       ec_ctx;
-gcry_mpi_point_t ec_gen;
-gcry_mpi_point_t ec_zero;
-gcry_mpi_t       ec_n;
 
 /**
  * brandt_crypto_init
@@ -175,39 +172,16 @@ brandt_mpi_scan_unsigned (gcry_mpi_t *result, const void *data, size_t size)
 }
 
 
-//gcry_mpi_point_t
-//deserialize_point(const struct brandt_point* data, const int len)
-//{
-//	gcry_sexp_t s;
-//	gcry_ctx_t ctx;
-//	gcry_mpi_point_t ret;
-//	gcry_error_t rc;
-//
-//	rc = gcry_sexp_build(&s, NULL, "(public-key(ecc(curve " CURVE ")(q %b)))",
-//						 len, data);
-//	brandt_assert_gpgerr(rc);
-//
-//	rc = gcry_mpi_ec_new(&ctx, s, NULL);
-//	brandt_assert_gpgerr(rc);
-//	gcry_sexp_release(s);
-//
-//	ret = gcry_mpi_ec_get_point("q", ctx, 0);
-//	brandt_assert(ret);
-//	gcry_ctx_release(ctx);
-//	return ret;
-//}
-
-
 /* --- EC --- */
 
 /**
- * brandt_ec_skey_create
+ * ec_skey_create
  *
  * @param[out] skey where to store the generated secret key. This has to be an
  * already initialized mpi.
  */
 void
-brandt_ec_skey_create (gcry_mpi_t skey)
+ec_skey_create (gcry_mpi_t skey)
 {
 	gcry_mpi_t   ret;
 	gcry_sexp_t  s_keyparam;
@@ -241,45 +215,45 @@ brandt_ec_skey_create (gcry_mpi_t skey)
 
 
 /**
- * brandt_ec_keypair_create
+ * ec_keypair_create
  *
  * @param[out] pkey where to store the generated public key
  * @param[out] skey where to store the generated secret key
  */
 void
-brandt_ec_keypair_create (gcry_mpi_point_t pkey, gcry_mpi_t skey)
+ec_keypair_create (gcry_mpi_point_t pkey, gcry_mpi_t skey)
 {
 	brandt_assert (NULL != pkey);
 	brandt_assert (NULL != skey);
 
-	brandt_ec_skey_create (skey);
+	ec_skey_create (skey);
 	gcry_mpi_ec_mul (pkey, skey, ec_gen, ec_ctx);
 }
 
 
 /**
- * brandt_ec_keypair_create_base
+ * ec_keypair_create_base
  *
  * @param[out] pkey where to store the generated public key
  * @param[out] skey where to store the generated secret key
  * @param[in] base which base point should be used to calculate the public key
  */
 void
-brandt_ec_keypair_create_base (gcry_mpi_point_t       pkey,
-                               gcry_mpi_t             skey,
-                               const gcry_mpi_point_t base)
+ec_keypair_create_base (gcry_mpi_point_t       pkey,
+                        gcry_mpi_t             skey,
+                        const gcry_mpi_point_t base)
 {
 	brandt_assert (NULL != pkey);
 	brandt_assert (NULL != skey);
 	brandt_assert (NULL != base);
 
-	brandt_ec_skey_create (skey);
+	ec_skey_create (skey);
 	gcry_mpi_ec_mul (pkey, skey, base, ec_ctx);
 }
 
 
 /**
- * brandt_ec_point_cmp compares two curve points
+ * ec_point_cmp compares two curve points
  *
  * @param[in] a the first point
  * @param[in] b the second point
@@ -287,7 +261,7 @@ brandt_ec_keypair_create_base (gcry_mpi_point_t       pkey,
  * else otherwise
  */
 int
-brandt_ec_point_cmp (const gcry_mpi_point_t a, const gcry_mpi_point_t b)
+ec_point_cmp (const gcry_mpi_point_t a, const gcry_mpi_point_t b)
 {
 	int        ret = 1;
 	gcry_mpi_t ax = gcry_mpi_new (0);
@@ -316,24 +290,431 @@ brandt_ec_point_cmp (const gcry_mpi_point_t a, const gcry_mpi_point_t b)
 }
 
 
+static gcry_mpi_point_t **
+smc_init2 (uint16_t size1, uint16_t size2)
+{
+	uint16_t         i, j;
+	gcry_mpi_point_t **ret;
+	gcry_mpi_point_t *data;
+
+	ret = calloc (size1, sizeof (*ret) + (size2 * sizeof (**ret)));
+	brandt_assert (NULL != ret);
+	data = (gcry_mpi_point_t *)&ret[size1];
+	for (i = 0; i < size1; i++)
+	{
+		ret[i] = &data[i * size2];
+		for (j = 0; j < size2; j++)
+			ret[i][j] = gcry_mpi_point_new (0);
+	}
+	return ret;
+}
+
+
+static void
+smc_free2 (gcry_mpi_point_t **dst, uint16_t size1, uint16_t size2)
+{
+	uint16_t i, j;
+
+	for (i = 0; i < size1; i++)
+		for (j = 0; j < size2; j++)
+			gcry_mpi_point_release (dst[i][j]);
+	free (dst);
+}
+
+
+/**
+ * smc_sums_partial calculates sums up until the current index and stores them
+ * in @a out. @$f\forall i \leq len: out_i=sum_{h=1}^iin_h@$f
+ *
+ * @param[out] out Where to store the resulting sums. Points may be given
+ * uninitialized, but the appropriate amount of memory has to be allocated
+ * beforehand.
+ * @param[in] in Input points.
+ * @param[in] len The length of both @a out and @a in.
+ */
+static void
+smc_sums_partial (gcry_mpi_point_t out[], gcry_mpi_point_t in[], uint16_t len)
+{
+	uint16_t i;
+
+	for (i = 0; i < len; i++)
+	{
+		out[i] = gcry_mpi_point_new (0);
+		gcry_mpi_ec_add (out[i], in[i], (i ? out[i - 1] : ec_zero), ec_ctx);
+		brandt_assert (NULL != out[i]);
+	}
+}
+
+
 /**
- * Clear memory that was used to store a private key.
+ * smc_sum calculates the sum of all input points. @$fout=sum_{i=1}^{len}in_i@$f
  *
- * @param skey location of the key
+ * @param[out] out Where to store the result
+ * @param[in] in Input points.
+ * @param[in] len The length of @a in.
+ */
+static void
+smc_sum (gcry_mpi_point_t out, gcry_mpi_point_t in[], uint16_t len)
+{
+	uint16_t i;
+
+	brandt_assert (NULL != out);
+	/**TODO: how to copy a point more efficiently? */
+	gcry_mpi_ec_add (out, ec_zero, ec_zero, ec_ctx);
+	for (i = 0; i < len; i++)
+		gcry_mpi_ec_add (out, out, in[i], ec_ctx);
+}
+
+
+/**
+ * smc_compute_pkey calculates the shared public key
+ *
+ * @param[in,out] ad The struct AuctionData used
  */
 void
-brandt_ec_key_clear (struct brandt_ec_skey *skey)
+smc_compute_pkey (struct AuctionData *ad)
 {
-	memset (skey, 0, sizeof (struct brandt_ec_skey));
+	ad->Y = gcry_mpi_point_new (0);
+	smc_sum (ad->Y, ad->y, ad->n);
+}
+
+
+/**
+ * smc_zkp_dl
+ *
+ * @param v TODO
+ * @param g TODO
+ * @param x TODO
+ * @param a TODO
+ * @param c TODO
+ * @param r TODO
+ */
+void
+smc_zkp_dl (const gcry_mpi_point_t v,
+            const gcry_mpi_point_t g,
+            const gcry_mpi_t       x,
+            const gcry_mpi_point_t a,
+            gcry_mpi_t             c,
+            gcry_mpi_t             r)
+{
+	gcry_mpi_t z = gcry_mpi_new (0);
+
+	ec_keypair_create_base (a, z, g);
+
+	/* compute challange c */
+	/**TODO: generate c from HASH(g,v,a) and don't output it */
+	ec_skey_create (c);
+	gcry_mpi_mod (c, c, ec_n);
+
+	gcry_mpi_mulm (r, c, x, ec_n);
+	gcry_mpi_addm (r, r, z, ec_n);
+
+	gcry_mpi_release (z);
 }
 
 
 /**
- * Generate a random value mod n.
+ * smc_zkp_dl_check
  *
- * @param edc ECC context
- * @return random value mod n.
+ * @param v TODO
+ * @param g TODO
+ * @param a TODO
+ * @param c TODO
+ * @param r TODO
+ * @return 0 if the proof is correct, something else otherwise
  */
+int
+smc_zkp_dl_check (const gcry_mpi_point_t v,
+                  const gcry_mpi_point_t g,
+                  const gcry_mpi_point_t a,
+                  const gcry_mpi_t       c,
+                  const gcry_mpi_t       r)
+{
+	int              ret;
+	gcry_mpi_point_t left = gcry_mpi_point_new (0);
+	gcry_mpi_point_t right = gcry_mpi_point_new (0);
+
+	gcry_mpi_ec_mul (left, r, g, ec_ctx);
+	gcry_mpi_ec_mul (right, c, v, ec_ctx);
+	gcry_mpi_ec_add (right, a, right, ec_ctx);
+
+	ret = ec_point_cmp (left, right);
+	gcry_mpi_point_release (left);
+	gcry_mpi_point_release (right);
+
+	return ret;
+}
+
+
+void
+smc_zkp_2dle (const gcry_mpi_point_t v,
+              const gcry_mpi_point_t w,
+              const gcry_mpi_point_t g1,
+              const gcry_mpi_point_t g2,
+              const gcry_mpi_t       x,
+              gcry_mpi_point_t       a,
+              gcry_mpi_point_t       b,
+              gcry_mpi_t             c,
+              gcry_mpi_t             r)
+{
+	gcry_mpi_t z = gcry_mpi_new (0);
+
+	ec_keypair_create_base (a, z, g1);
+	gcry_mpi_ec_mul (b, z, g2, ec_ctx);
+
+	/* compute challange c */
+	/**TODO: generate c from HASH(g1,g2,v,w,a,b) and don't output it */
+	ec_skey_create (c);
+	gcry_mpi_mod (c, c, ec_n);
+
+	gcry_mpi_mulm (r, c, x, ec_n);
+	gcry_mpi_addm (r, r, z, ec_n);
+
+	gcry_mpi_release (z);
+}
+
+
+int
+smc_zkp_2dle_check (const gcry_mpi_point_t v,
+                    const gcry_mpi_point_t w,
+                    const gcry_mpi_point_t g1,
+                    const gcry_mpi_point_t g2,
+                    const gcry_mpi_point_t a,
+                    const gcry_mpi_point_t b,
+                    const gcry_mpi_t       c,
+                    const gcry_mpi_t       r)
+{
+	int              ret;
+	gcry_mpi_point_t left = gcry_mpi_point_new (0);
+	gcry_mpi_point_t right = gcry_mpi_point_new (0);
+
+	gcry_mpi_ec_mul (left, r, g1, ec_ctx);
+	gcry_mpi_ec_mul (right, c, v, ec_ctx);
+	gcry_mpi_ec_add (right, a, right, ec_ctx);
+	ret = ec_point_cmp (left, right);
+
+	gcry_mpi_ec_mul (left, r, g2, ec_ctx);
+	gcry_mpi_ec_mul (right, c, w, ec_ctx);
+	gcry_mpi_ec_add (right, b, right, ec_ctx);
+	ret |= ec_point_cmp (left, right);
+
+	gcry_mpi_point_release (left);
+	gcry_mpi_point_release (right);
+
+	return ret;
+}
+
+
+void
+smc_zkp_0og (gcry_mpi_point_t       alpha,
+             const gcry_mpi_point_t m,
+             const gcry_mpi_point_t y,
+             gcry_mpi_point_t       beta,
+             gcry_mpi_point_t       a1,
+             gcry_mpi_point_t       a2,
+             gcry_mpi_point_t       b1,
+             gcry_mpi_point_t       b2,
+             gcry_mpi_t             c,
+             gcry_mpi_t             d1,
+             gcry_mpi_t             d2,
+             gcry_mpi_t             r1,
+             gcry_mpi_t             r2)
+{
+	gcry_mpi_t r = gcry_mpi_new (0);
+	gcry_mpi_t w = gcry_mpi_new (0);
+	int        eq0 = !ec_point_cmp (m, ec_zero);
+	int        eqg = !ec_point_cmp (m, ec_gen);
+
+	if (!(eq0 ^ eqg))
+		eprintf ("zero knowledge proof: m is neither 0 nor g");
+
+	/* beta = r*g */
+	ec_keypair_create (beta, r);
+	gcry_mpi_mod (r, r, ec_n);
+
+	/* alpha = m + r*y */
+	gcry_mpi_ec_mul (alpha, r, y, ec_ctx);
+	gcry_mpi_ec_add (alpha, m, alpha, ec_ctx);
+
+	if (eq0)
+	{   /* m == 0 */
+		ec_keypair_create_base (a1, d1, beta);
+		gcry_mpi_mod (d1, d1, ec_n);
+		ec_keypair_create_base (b1, r1, y);
+		gcry_mpi_mod (r1, r1, ec_n);
+
+		/* a1 = r1*g + d1*beta */
+		gcry_mpi_ec_mul (a2, r1, ec_gen, ec_ctx);
+		gcry_mpi_ec_add (a1, a2, a1, ec_ctx);
+
+		/* b1 = r1*y + d1*(alpha-g) */
+		gcry_mpi_ec_sub (b2, alpha, ec_gen, ec_ctx);
+		gcry_mpi_ec_mul (a2, d1, b2, ec_ctx);
+		gcry_mpi_ec_add (b1, b1, a2, ec_ctx);
+
+		/* a2 = w * g */
+		ec_keypair_create_base (a2, w, ec_gen);
+		gcry_mpi_mod (w, w, ec_n);
+
+		/* b2 = w * y */
+		gcry_mpi_ec_mul (b2, w, y, ec_ctx);
+
+		/* compute challange c */
+		/**TODO: generate c from HASH(alpha,beta,a1,b1,a2,b2) and don't output it */
+		ec_skey_create (c);
+		gcry_mpi_mod (c, c, ec_n);
+
+		/* d2 = c - d1 */
+		gcry_mpi_subm (d2, c, d1, ec_n);
+
+		/* r2 = w - r*d2 */
+		gcry_mpi_mulm (r2, r, d2, ec_n);
+		gcry_mpi_subm (r2, w, r2, ec_n);
+	}
+	else
+	{   /* m == g */
+		ec_keypair_create_base (a2, d2, beta);
+		gcry_mpi_mod (d2, d2, ec_n);
+		ec_keypair_create_base (b2, r2, y);
+		gcry_mpi_mod (r2, r2, ec_n);
+
+		/* a2 = r2*g + d2*beta */
+		gcry_mpi_ec_mul (a1, r2, ec_gen, ec_ctx);
+		gcry_mpi_ec_add (a2, a1, a2, ec_ctx);
+
+		/* b2 = r2*y + d2*(alpha-0) */
+		/* useless subtraction to have same amount of operations as in m == 0 */
+		gcry_mpi_ec_sub (b1, alpha, ec_zero, ec_ctx);
+		gcry_mpi_ec_mul (a1, d2, b1, ec_ctx);
+		gcry_mpi_ec_add (b2, b2, a1, ec_ctx);
+
+		/* a1 = w * g */
+		ec_keypair_create_base (a1, w, ec_gen);
+		gcry_mpi_mod (w, w, ec_n);
+
+		/* b1 = w * y */
+		gcry_mpi_ec_mul (b1, w, y, ec_ctx);
+
+		/* compute challange c */
+		/**TODO: generate c from HASH(alpha,beta,a1,b1,a2,b2) and don't output it */
+		ec_skey_create (c);
+		gcry_mpi_mod (c, c, ec_n);
+
+		/* d1 = c - d2 */
+		gcry_mpi_subm (d1, c, d2, ec_n);
+
+		/* r1 = w - r*d1 */
+		gcry_mpi_mulm (r1, r, d1, ec_n);
+		gcry_mpi_subm (r1, w, r1, ec_n);
+	}
+
+	gcry_mpi_release (r);
+	gcry_mpi_release (w);
+}
+
+
+int
+smc_zkp_0og_check (const gcry_mpi_point_t alpha,
+                   const gcry_mpi_point_t y,
+                   const gcry_mpi_point_t beta,
+                   const gcry_mpi_point_t a1,
+                   const gcry_mpi_point_t a2,
+                   const gcry_mpi_point_t b1,
+                   const gcry_mpi_point_t b2,
+                   const gcry_mpi_t       c,
+                   const gcry_mpi_t       d1,
+                   const gcry_mpi_t       d2,
+                   const gcry_mpi_t       r1,
+                   const gcry_mpi_t       r2)
+{
+	int              ret;
+	gcry_mpi_t       sum = gcry_mpi_new (0);
+	gcry_mpi_point_t right = gcry_mpi_point_new (0);
+	gcry_mpi_point_t tmp = gcry_mpi_point_new (0);
+
+	/* c == d1 + d2 */
+	gcry_mpi_addm (sum, d1, d2, ec_n);
+	ret = gcry_mpi_cmp (c, sum);
+
+	/* a1 == r1*g + d1*beta */
+	gcry_mpi_ec_mul (tmp, r1, ec_gen, ec_ctx);
+	gcry_mpi_ec_mul (right, d1, beta, ec_ctx);
+	gcry_mpi_ec_add (right, tmp, right, ec_ctx);
+	ret |= ec_point_cmp (a1, right) << 1;
+
+	/* b1 == r1*y + d1*(alpha-g) */
+	gcry_mpi_ec_sub (right, alpha, ec_gen, ec_ctx);
+	gcry_mpi_ec_mul (tmp, d1, right, ec_ctx);
+	gcry_mpi_ec_mul (right, r1, y, ec_ctx);
+	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
+	ret |= ec_point_cmp (b1, right) << 2;
+
+	/* a2 == r2*g + d2*beta */
+	gcry_mpi_ec_mul (tmp, d2, beta, ec_ctx);
+	gcry_mpi_ec_mul (right, r2, ec_gen, ec_ctx);
+	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
+	ret |= ec_point_cmp (a2, right) << 3;
+
+	/* b2 == r2*y + d2*alpha */
+	gcry_mpi_ec_mul (tmp, d2, alpha, ec_ctx);
+	gcry_mpi_ec_mul (right, r2, y, ec_ctx);
+	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
+	ret |= ec_point_cmp (b2, right) << 4;
+
+	gcry_mpi_release (sum);
+	gcry_mpi_point_release (right);
+	gcry_mpi_point_release (tmp);
+
+	if (ret)
+		weprintf ("ret: 0x%x", ret);
+	return ret;
+}
+
+
+/* --- unused stuff, might become useful later --- */
+
+///**
+// * Clear memory that was used to store a private key.
+// *
+// * @param skey the key
+// */
+//void
+//brandt_ec_key_clear (gcry_mpi_t skey)
+//{
+//	gcry_mpi_randomize (skey, 256, GCRY_WEAK_RANDOM);
+//	gcry_mpi_release (skey);
+//}
+
+
+//gcry_mpi_point_t
+//deserialize_point(const struct brandt_point* data, const int len)
+//{
+//	gcry_sexp_t s;
+//	gcry_ctx_t ctx;
+//	gcry_mpi_point_t ret;
+//	gcry_error_t rc;
+//
+//	rc = gcry_sexp_build(&s, NULL, "(public-key(ecc(curve " CURVE ")(q %b)))",
+//						 len, data);
+//	brandt_assert_gpgerr(rc);
+//
+//	rc = gcry_mpi_ec_new(&ctx, s, NULL);
+//	brandt_assert_gpgerr(rc);
+//	gcry_sexp_release(s);
+//
+//	ret = gcry_mpi_ec_get_point("q", ctx, 0);
+//	brandt_assert(ret);
+//	gcry_ctx_release(ctx);
+//	return ret;
+//}
+
+
+///**
+// * Generate a random value mod n.
+// *
+// * @param edc ECC context
+// * @return random value mod n.
+// */
 //gcry_mpi_t
 //GNUNET_CRYPTO_ecc_random_mod_n (struct GNUNET_CRYPTO_EccDlogContext *edc)
 //{
diff --git a/crypto.h b/crypto.h
index 9596a7b..e736236 100644
--- a/crypto.h
+++ b/crypto.h
@@ -52,12 +52,76 @@ void brandt_mpi_scan_unsigned (gcry_mpi_t *result,
 
 /* --- EC --- */
 
-void brandt_ec_skey_create (gcry_mpi_t skey);
-void brandt_ec_pkey_compute (gcry_mpi_point_t *pkey, const gcry_mpi_t skey);
-void brandt_ec_keypair_create (gcry_mpi_point_t pkey, gcry_mpi_t skey);
-void brandt_ec_keypair_create_base (gcry_mpi_point_t       pkey,
-                                    gcry_mpi_t             skey,
-                                    const gcry_mpi_point_t base);
-int brandt_ec_point_cmp (const gcry_mpi_point_t a, const gcry_mpi_point_t b);
+struct ec_point {
+	unsigned char data[256 / 8];
+};
+
+int ec_point_cmp (const gcry_mpi_point_t a, const gcry_mpi_point_t b);
+void ec_skey_create (gcry_mpi_t skey);
+void ec_keypair_create (gcry_mpi_point_t pkey, gcry_mpi_t skey);
+void ec_keypair_create_base (gcry_mpi_point_t       pkey,
+                             gcry_mpi_t             skey,
+                             const gcry_mpi_point_t base);
+
+
+
+
+/* --- Zero knowledge proofs --- */
+
+void smc_zkp_dl (const gcry_mpi_point_t v,
+                 const gcry_mpi_point_t g,
+                 const gcry_mpi_t       x,
+                 const gcry_mpi_point_t a,
+                 gcry_mpi_t             c,
+                 gcry_mpi_t             r);
+int smc_zkp_dl_check (const gcry_mpi_point_t v,
+                      const gcry_mpi_point_t g,
+                      const gcry_mpi_point_t a,
+                      const gcry_mpi_t       c,
+                      const gcry_mpi_t       r);
+
+void smc_zkp_2dle (const gcry_mpi_point_t v,
+                   const gcry_mpi_point_t w,
+                   const gcry_mpi_point_t g1,
+                   const gcry_mpi_point_t g2,
+                   const gcry_mpi_t       x,
+                   gcry_mpi_point_t       a,
+                   gcry_mpi_point_t       b,
+                   gcry_mpi_t             c,
+                   gcry_mpi_t             r);
+int smc_zkp_2dle_check (const gcry_mpi_point_t v,
+                        const gcry_mpi_point_t w,
+                        const gcry_mpi_point_t g1,
+                        const gcry_mpi_point_t g2,
+                        const gcry_mpi_point_t a,
+                        const gcry_mpi_point_t b,
+                        const gcry_mpi_t       c,
+                        const gcry_mpi_t       r);
+
+void smc_zkp_0og (gcry_mpi_point_t       alpha,
+                  const gcry_mpi_point_t m,
+                  const gcry_mpi_point_t y,
+                  gcry_mpi_point_t       beta,
+                  gcry_mpi_point_t       a1,
+                  gcry_mpi_point_t       a2,
+                  gcry_mpi_point_t       b1,
+                  gcry_mpi_point_t       b2,
+                  gcry_mpi_t             c,
+                  gcry_mpi_t             d1,
+                  gcry_mpi_t             d2,
+                  gcry_mpi_t             r1,
+                  gcry_mpi_t             r2);
+int smc_zkp_0og_check (const gcry_mpi_point_t alpha,
+                       const gcry_mpi_point_t y,
+                       const gcry_mpi_point_t beta,
+                       const gcry_mpi_point_t a1,
+                       const gcry_mpi_point_t a2,
+                       const gcry_mpi_point_t b1,
+                       const gcry_mpi_point_t b2,
+                       const gcry_mpi_t       c,
+                       const gcry_mpi_t       d1,
+                       const gcry_mpi_t       d2,
+                       const gcry_mpi_t       r1,
+                       const gcry_mpi_t       r2);
 
 #endif /* ifndef _BRANDT_CRYPTO_H */
diff --git a/smc.c b/smc.c
deleted file mode 100644
index debc5b4..0000000
--- a/smc.c
+++ /dev/null
@@ -1,403 +0,0 @@
-/* This file is part of libbrandt.
- * Copyright (C) 2016 GNUnet e.V.
- *
- * libbrandt is free software: you can redistribute it and/or modify it under
- * the terms of the GNU General Public License as published by the Free Software
- * Foundation, either version 3 of the License, or (at your option) any later
- * version.
- *
- * libbrandt is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * libbrandt.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-/**
- * @file smc.c
- * @brief Implementation of the smc primitives.
- */
-
-#include <gcrypt.h>
-
-#include "crypto.h"
-#include "internals.h"
-#include "smc.h"
-#include "util.h"
-
-extern gcry_ctx_t       ec_ctx;
-extern gcry_mpi_point_t ec_gen;
-extern gcry_mpi_point_t ec_zero;
-extern gcry_mpi_t       ec_n;
-
-
-/**
- * smc_sums_partial calculates sums up until the current index and stores them
- * in @a out. @$f\forall i \leq len: out_i=sum_{h=1}^iin_h@$f
- *
- * @param[out] out Where to store the resulting sums. Points may be given
- * uninitialized, but the appropriate amount of memory has to be allocated
- * beforehand.
- * @param[in] in Input points.
- * @param[in] len The length of both @a out and @a in.
- */
-static void
-smc_sums_partial (gcry_mpi_point_t out[], gcry_mpi_point_t in[], uint16_t len)
-{
-	uint16_t i;
-
-	for (i = 0; i < len; i++)
-	{
-		out[i] = gcry_mpi_point_new (0);
-		gcry_mpi_ec_add (out[i], in[i], (i ? out[i - 1] : ec_zero), ec_ctx);
-		brandt_assert (NULL != out[i]);
-	}
-}
-
-
-/**
- * smc_sum calculates the sum of all input points. @$fout=sum_{i=1}^{len}in_i@$f
- *
- * @param[out] out Where to store the result
- * @param[in] in Input points.
- * @param[in] len The length of @a in.
- */
-static void
-smc_sum (gcry_mpi_point_t out, gcry_mpi_point_t in[], uint16_t len)
-{
-	uint16_t i;
-
-	brandt_assert (NULL != out);
-	/**TODO: how to copy a point more efficiently? */
-	gcry_mpi_ec_add (out, ec_zero, ec_zero, ec_ctx);
-	for (i = 0; i < len; i++)
-		gcry_mpi_ec_add (out, out, in[i], ec_ctx);
-}
-
-
-/**
- * smc_compute_pkey calculates the shared public key
- *
- * @param[in,out] ad The struct AuctionData used
- */
-void
-smc_compute_pkey (struct AuctionData *ad)
-{
-	ad->Y = gcry_mpi_point_new (0);
-	smc_sum (ad->Y, ad->y, ad->n);
-}
-
-
-/**
- * smc_zkp_dl
- *
- * @param v TODO
- * @param g TODO
- * @param x TODO
- * @param a TODO
- * @param c TODO
- * @param r TODO
- */
-void
-smc_zkp_dl (const gcry_mpi_point_t v,
-            const gcry_mpi_point_t g,
-            const gcry_mpi_t       x,
-            const gcry_mpi_point_t a,
-            gcry_mpi_t             c,
-            gcry_mpi_t             r)
-{
-	gcry_mpi_t z = gcry_mpi_new (0);
-
-	brandt_ec_keypair_create_base (a, z, g);
-
-	/* compute challange c */
-	/**TODO: generate c from HASH(g,v,a) and don't output it */
-	brandt_ec_skey_create (c);
-	gcry_mpi_mod (c, c, ec_n);
-
-	gcry_mpi_mulm (r, c, x, ec_n);
-	gcry_mpi_addm (r, r, z, ec_n);
-
-	gcry_mpi_release (z);
-}
-
-
-/**
- * smc_zkp_dl_check
- *
- * @param v TODO
- * @param g TODO
- * @param a TODO
- * @param c TODO
- * @param r TODO
- * @return 0 if the proof is correct, something else otherwise
- */
-int
-smc_zkp_dl_check (const gcry_mpi_point_t v,
-                  const gcry_mpi_point_t g,
-                  const gcry_mpi_point_t a,
-                  const gcry_mpi_t       c,
-                  const gcry_mpi_t       r)
-{
-	int              ret;
-	gcry_mpi_point_t left = gcry_mpi_point_new (0);
-	gcry_mpi_point_t right = gcry_mpi_point_new (0);
-
-	gcry_mpi_ec_mul (left, r, g, ec_ctx);
-	gcry_mpi_ec_mul (right, c, v, ec_ctx);
-	gcry_mpi_ec_add (right, a, right, ec_ctx);
-
-	ret = brandt_ec_point_cmp (left, right);
-	gcry_mpi_point_release (left);
-	gcry_mpi_point_release (right);
-
-	return ret;
-}
-
-
-void
-smc_zkp_2dle (const gcry_mpi_point_t v,
-              const gcry_mpi_point_t w,
-              const gcry_mpi_point_t g1,
-              const gcry_mpi_point_t g2,
-              const gcry_mpi_t       x,
-              gcry_mpi_point_t       a,
-              gcry_mpi_point_t       b,
-              gcry_mpi_t             c,
-              gcry_mpi_t             r)
-{
-	gcry_mpi_t z = gcry_mpi_new (0);
-
-	brandt_ec_keypair_create_base (a, z, g1);
-	gcry_mpi_ec_mul (b, z, g2, ec_ctx);
-
-	/* compute challange c */
-	/**TODO: generate c from HASH(g1,g2,v,w,a,b) and don't output it */
-	brandt_ec_skey_create (c);
-	gcry_mpi_mod (c, c, ec_n);
-
-	gcry_mpi_mulm (r, c, x, ec_n);
-	gcry_mpi_addm (r, r, z, ec_n);
-
-	gcry_mpi_release (z);
-}
-
-
-int
-smc_zkp_2dle_check (const gcry_mpi_point_t v,
-                    const gcry_mpi_point_t w,
-                    const gcry_mpi_point_t g1,
-                    const gcry_mpi_point_t g2,
-                    const gcry_mpi_point_t a,
-                    const gcry_mpi_point_t b,
-                    const gcry_mpi_t       c,
-                    const gcry_mpi_t       r)
-{
-	int              ret;
-	gcry_mpi_point_t left = gcry_mpi_point_new (0);
-	gcry_mpi_point_t right = gcry_mpi_point_new (0);
-
-	gcry_mpi_ec_mul (left, r, g1, ec_ctx);
-	gcry_mpi_ec_mul (right, c, v, ec_ctx);
-	gcry_mpi_ec_add (right, a, right, ec_ctx);
-	ret = brandt_ec_point_cmp (left, right);
-
-	gcry_mpi_ec_mul (left, r, g2, ec_ctx);
-	gcry_mpi_ec_mul (right, c, w, ec_ctx);
-	gcry_mpi_ec_add (right, b, right, ec_ctx);
-	ret |= brandt_ec_point_cmp (left, right);
-
-	gcry_mpi_point_release (left);
-	gcry_mpi_point_release (right);
-
-	return ret;
-}
-
-
-void
-smc_zkp_0og (gcry_mpi_point_t       alpha,
-             const gcry_mpi_point_t m,
-             const gcry_mpi_point_t y,
-             gcry_mpi_point_t       beta,
-             gcry_mpi_point_t       a1,
-             gcry_mpi_point_t       a2,
-             gcry_mpi_point_t       b1,
-             gcry_mpi_point_t       b2,
-             gcry_mpi_t             c,
-             gcry_mpi_t             d1,
-             gcry_mpi_t             d2,
-             gcry_mpi_t             r1,
-             gcry_mpi_t             r2)
-{
-	gcry_mpi_t r = gcry_mpi_new (0);
-	gcry_mpi_t w = gcry_mpi_new (0);
-	int        eq0 = !brandt_ec_point_cmp (m, ec_zero);
-	int        eqg = !brandt_ec_point_cmp (m, ec_gen);
-
-	if (!(eq0 ^ eqg))
-		eprintf ("zero knowledge proof: m is neither 0 nor g");
-
-	/* beta = r*g */
-	brandt_ec_keypair_create (beta, r);
-	gcry_mpi_mod (r, r, ec_n);
-
-	/* alpha = m + r*y */
-	gcry_mpi_ec_mul (alpha, r, y, ec_ctx);
-	gcry_mpi_ec_add (alpha, m, alpha, ec_ctx);
-
-	if (eq0)
-	{   /* m == 0 */
-		brandt_ec_keypair_create_base (a1, d1, beta);
-		gcry_mpi_mod (d1, d1, ec_n);
-		brandt_ec_keypair_create_base (b1, r1, y);
-		gcry_mpi_mod (r1, r1, ec_n);
-
-		/* a1 = r1*g + d1*beta */
-		gcry_mpi_ec_mul (a2, r1, ec_gen, ec_ctx);
-		gcry_mpi_ec_add (a1, a2, a1, ec_ctx);
-
-		/* b1 = r1*y + d1*(alpha-g) */
-		gcry_mpi_ec_sub (b2, alpha, ec_gen, ec_ctx);
-		gcry_mpi_ec_mul (a2, d1, b2, ec_ctx);
-		gcry_mpi_ec_add (b1, b1, a2, ec_ctx);
-
-		/* a2 = w * g */
-		brandt_ec_keypair_create_base (a2, w, ec_gen);
-		gcry_mpi_mod (w, w, ec_n);
-
-		/* b2 = w * y */
-		gcry_mpi_ec_mul (b2, w, y, ec_ctx);
-
-		/* compute challange c */
-		/**TODO: generate c from HASH(alpha,beta,a1,b1,a2,b2) and don't output it */
-		brandt_ec_skey_create (c);
-		gcry_mpi_mod (c, c, ec_n);
-
-		/* d2 = c - d1 */
-		gcry_mpi_subm (d2, c, d1, ec_n);
-
-		/* r2 = w - r*d2 */
-		gcry_mpi_mulm (r2, r, d2, ec_n);
-		gcry_mpi_subm (r2, w, r2, ec_n);
-	}
-	else
-	{   /* m == g */
-		brandt_ec_keypair_create_base (a2, d2, beta);
-		gcry_mpi_mod (d2, d2, ec_n);
-		brandt_ec_keypair_create_base (b2, r2, y);
-		gcry_mpi_mod (r2, r2, ec_n);
-
-		/* a2 = r2*g + d2*beta */
-		gcry_mpi_ec_mul (a1, r2, ec_gen, ec_ctx);
-		gcry_mpi_ec_add (a2, a1, a2, ec_ctx);
-
-		/* b2 = r2*y + d2*(alpha-0) */
-		/* useless subtraction to have same amount of operations as in m == 0 */
-		gcry_mpi_ec_sub (b1, alpha, ec_zero, ec_ctx);
-		gcry_mpi_ec_mul (a1, d2, b1, ec_ctx);
-		gcry_mpi_ec_add (b2, b2, a1, ec_ctx);
-
-		/* a1 = w * g */
-		brandt_ec_keypair_create_base (a1, w, ec_gen);
-		gcry_mpi_mod (w, w, ec_n);
-
-		/* b1 = w * y */
-		gcry_mpi_ec_mul (b1, w, y, ec_ctx);
-
-		/* compute challange c */
-		/**TODO: generate c from HASH(alpha,beta,a1,b1,a2,b2) and don't output it */
-		brandt_ec_skey_create (c);
-		gcry_mpi_mod (c, c, ec_n);
-
-		/* d1 = c - d2 */
-		gcry_mpi_subm (d1, c, d2, ec_n);
-
-		/* r1 = w - r*d1 */
-		gcry_mpi_mulm (r1, r, d1, ec_n);
-		gcry_mpi_subm (r1, w, r1, ec_n);
-	}
-
-	gcry_mpi_release (r);
-	gcry_mpi_release (w);
-}
-
-
-int
-smc_zkp_0og_check (const gcry_mpi_point_t alpha,
-                   const gcry_mpi_point_t y,
-                   const gcry_mpi_point_t beta,
-                   const gcry_mpi_point_t a1,
-                   const gcry_mpi_point_t a2,
-                   const gcry_mpi_point_t b1,
-                   const gcry_mpi_point_t b2,
-                   const gcry_mpi_t       c,
-                   const gcry_mpi_t       d1,
-                   const gcry_mpi_t       d2,
-                   const gcry_mpi_t       r1,
-                   const gcry_mpi_t       r2)
-{
-	int              ret;
-	gcry_mpi_t       sum = gcry_mpi_new (0);
-	gcry_mpi_point_t right = gcry_mpi_point_new (0);
-	gcry_mpi_point_t tmp = gcry_mpi_point_new (0);
-
-	/* c == d1 + d2 */
-	gcry_mpi_addm (sum, d1, d2, ec_n);
-	ret = gcry_mpi_cmp (c, sum);
-
-	/* a1 == r1*g + d1*beta */
-	gcry_mpi_ec_mul (tmp, r1, ec_gen, ec_ctx);
-	gcry_mpi_ec_mul (right, d1, beta, ec_ctx);
-	gcry_mpi_ec_add (right, tmp, right, ec_ctx);
-	ret |= brandt_ec_point_cmp (a1, right) << 1;
-
-	/* b1 == r1*y + d1*(alpha-g) */
-	gcry_mpi_ec_sub (right, alpha, ec_gen, ec_ctx);
-	gcry_mpi_ec_mul (tmp, d1, right, ec_ctx);
-	gcry_mpi_ec_mul (right, r1, y, ec_ctx);
-	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
-	ret |= brandt_ec_point_cmp (b1, right) << 2;
-
-	/* a2 == r2*g + d2*beta */
-	gcry_mpi_ec_mul (tmp, d2, beta, ec_ctx);
-	gcry_mpi_ec_mul (right, r2, ec_gen, ec_ctx);
-	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
-	ret |= brandt_ec_point_cmp (a2, right) << 3;
-
-	/* b2 == r2*y + d2*alpha */
-	gcry_mpi_ec_mul (tmp, d2, alpha, ec_ctx);
-	gcry_mpi_ec_mul (right, r2, y, ec_ctx);
-	gcry_mpi_ec_add (right, right, tmp, ec_ctx);
-	ret |= brandt_ec_point_cmp (b2, right) << 4;
-
-	gcry_mpi_release (sum);
-	gcry_mpi_point_release (right);
-	gcry_mpi_point_release (tmp);
-
-	if (ret)
-		weprintf ("ret: 0x%x", ret);
-	return ret;
-}
-
-
-//GEN
-//smc_hextodec (const char *s)
-//{
-//	size_t i;
-//	char c;
-//	pari_sp ltop = avma;
-//	GEN ret = gen_0;
-//
-//	for (i = 0; i < strlen (s); i++)
-//	{
-//		errno = 0;
-//		if (1 != sscanf (&s[i], "%1hhx", &c))
-//		{
-//			brandt_eprintf ("failed to parse hex (\"%s\") to decimal:", s);
-//			return NULL;
-//		}
-//		ret = addis (shifti (ret, 4), c);
-//	}
-//	return gerepilecopy (ltop, ret);
-//}
diff --git a/smc.h b/smc.h
deleted file mode 100644
index 6309123..0000000
--- a/smc.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/* This file is part of libbrandt.
- * Copyright (C) 2016 GNUnet e.V.
- *
- * libbrandt is free software: you can redistribute it and/or modify it under
- * the terms of the GNU General Public License as published by the Free Software
- * Foundation, either version 3 of the License, or (at your option) any later
- * version.
- *
- * libbrandt is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * libbrandt.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-/**
- * @file smc.h
- * @brief describes the secure multiparty computation interface.
- */
-
-#ifndef _BRANDT_SMC_H
-#define _BRANDT_SMC_H
-
-#include <gcrypt.h>
-
-void smc_zkp_dl (const gcry_mpi_point_t v,
-                 const gcry_mpi_point_t g,
-                 const gcry_mpi_t       x,
-                 const gcry_mpi_point_t a,
-                 gcry_mpi_t             c,
-                 gcry_mpi_t             r);
-int smc_zkp_dl_check (const gcry_mpi_point_t v,
-                      const gcry_mpi_point_t g,
-                      const gcry_mpi_point_t a,
-                      const gcry_mpi_t       c,
-                      const gcry_mpi_t       r);
-
-void smc_zkp_2dle (const gcry_mpi_point_t v,
-                   const gcry_mpi_point_t w,
-                   const gcry_mpi_point_t g1,
-                   const gcry_mpi_point_t g2,
-                   const gcry_mpi_t       x,
-                   gcry_mpi_point_t       a,
-                   gcry_mpi_point_t       b,
-                   gcry_mpi_t             c,
-                   gcry_mpi_t             r);
-int smc_zkp_2dle_check (const gcry_mpi_point_t v,
-                        const gcry_mpi_point_t w,
-                        const gcry_mpi_point_t g1,
-                        const gcry_mpi_point_t g2,
-                        const gcry_mpi_point_t a,
-                        const gcry_mpi_point_t b,
-                        const gcry_mpi_t       c,
-                        const gcry_mpi_t       r);
-
-void smc_zkp_0og (gcry_mpi_point_t       alpha,
-                  const gcry_mpi_point_t m,
-                  const gcry_mpi_point_t y,
-                  gcry_mpi_point_t       beta,
-                  gcry_mpi_point_t       a1,
-                  gcry_mpi_point_t       a2,
-                  gcry_mpi_point_t       b1,
-                  gcry_mpi_point_t       b2,
-                  gcry_mpi_t             c,
-                  gcry_mpi_t             d1,
-                  gcry_mpi_t             d2,
-                  gcry_mpi_t             r1,
-                  gcry_mpi_t             r2);
-int smc_zkp_0og_check (const gcry_mpi_point_t alpha,
-                       const gcry_mpi_point_t y,
-                       const gcry_mpi_point_t beta,
-                       const gcry_mpi_point_t a1,
-                       const gcry_mpi_point_t a2,
-                       const gcry_mpi_point_t b1,
-                       const gcry_mpi_point_t b2,
-                       const gcry_mpi_t       c,
-                       const gcry_mpi_t       d1,
-                       const gcry_mpi_t       d2,
-                       const gcry_mpi_t       r1,
-                       const gcry_mpi_t       r2);
-
-#endif // ifndef _BRANDT_SMC_H
diff --git a/test_crypto.c b/test_crypto.c
index 5cc2ed1..a42a643 100644
--- a/test_crypto.c
+++ b/test_crypto.c
@@ -18,15 +18,33 @@
  * @file test_crypto.c
  * @brief testing crypto and smc functions.
  */
+
+/* For testing static functions and variables we include the whole source */
+#include "crypto.c"
+
 #include "brandt.h"
 #include "crypto.h"
-#include "smc.h"
 #include "test.h"
 
-extern gcry_ctx_t       ec_ctx;
-extern gcry_mpi_point_t ec_gen;
-extern gcry_mpi_point_t ec_zero;
-extern gcry_mpi_t       ec_n;
+
+int
+test_smc_2d_array ()
+{
+	gcry_mpi_point_t **array;
+	uint16_t         size1 = 3;
+	uint16_t         size2 = 7;
+	uint16_t         i, j;
+
+	array = smc_init2 (size1, size2);
+	check (array, "memory allocation failed");
+
+	for (i = 0; i < size1; i++)
+		for (j = 0; j < size2; j++)
+			check (array[i][j], "point has not been initialized");
+
+	smc_free2 (array, size1, size2);
+}
+
 
 int
 test_smc_zkp_dl ()
@@ -38,7 +56,7 @@ test_smc_zkp_dl ()
 	gcry_mpi_point_t g = gcry_mpi_point_new (0);
 	gcry_mpi_point_t v = gcry_mpi_point_new (0);
 
-	brandt_ec_keypair_create (g, c);
+	ec_keypair_create (g, c);
 
 	if (0 == tests_run)
 	{
@@ -46,7 +64,7 @@ test_smc_zkp_dl ()
 		gcry_mpi_ec_mul (g, GCRYMPI_CONST_ONE, ec_gen, ec_ctx);
 	}
 
-	brandt_ec_keypair_create_base (v, x, g);
+	ec_keypair_create_base (v, x, g);
 
 	smc_zkp_dl (v, g, x, a, c, r);
 	check (!smc_zkp_dl_check (v, g, a, c, r), "zkp dl wrong");
@@ -77,8 +95,8 @@ test_smc_zkp_2dle ()
 	gcry_mpi_point_t v = gcry_mpi_point_new (0);
 	gcry_mpi_point_t w = gcry_mpi_point_new (0);
 
-	brandt_ec_keypair_create (g1, c);
-	brandt_ec_keypair_create (g2, c);
+	ec_keypair_create (g1, c);
+	ec_keypair_create (g2, c);
 
 	if (0 == tests_run)
 	{
@@ -87,7 +105,7 @@ test_smc_zkp_2dle ()
 		gcry_mpi_ec_mul (g2, GCRYMPI_CONST_ONE, ec_gen, ec_ctx);
 	}
 
-	brandt_ec_keypair_create_base (v, x, g1);
+	ec_keypair_create_base (v, x, g1);
 	gcry_mpi_ec_mul (w, x, g2, ec_ctx);
 
 	smc_zkp_2dle (v, w, g1, g2, x, a, b, c, r);
@@ -128,7 +146,7 @@ test_smc_zkp_0og ()
 	gcry_mpi_point_t b1 = gcry_mpi_point_new (0);
 	gcry_mpi_point_t b2 = gcry_mpi_point_new (0);
 
-	brandt_ec_keypair_create (y, c);
+	ec_keypair_create (y, c);
 
 	smc_zkp_0og (alpha, (tests_run % 2 ? ec_zero : ec_gen), y, beta, a1, a2, b1,
 	             b2, c, d1, d2, r1, r2);
@@ -161,10 +179,13 @@ test_smc_zkp_0og ()
 int
 main (int argc, char *argv[])
 {
-	int repeat = 32;
+	int repeat = 8;
 
 	BRANDT_init ();
 
+	/* tests that need to run only once */
+	run (test_smc_2d_array);
+
 	for (tests_run = 0; tests_run < repeat; tests_run++)
 	{
 		run (test_smc_zkp_dl);