un-debianize libd0_blind_id's RNG on Win32
authorRudolf Polzer <divverent@alientrap.org>
Thu, 5 Aug 2010 07:43:23 +0000 (09:43 +0200)
committerRudolf Polzer <divverent@alientrap.org>
Thu, 5 Aug 2010 07:43:23 +0000 (09:43 +0200)
d0_bignum-gmp.c
d0_blind_id.c

index 6a2f703..5f0babc 100644 (file)
@@ -17,6 +17,11 @@ License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
+#ifdef WIN32
+#include <windows.h>
+#include <wincrypt.h>
+#endif
+
 #include "d0_bignum.h"
 
 #include <gmp.h>
@@ -33,26 +38,43 @@ static d0_bignum_t temp;
 
 #include <time.h>
 #include <stdio.h>
+
 void d0_bignum_INITIALIZE(void)
 {
        FILE *f;
+       unsigned char buf[256];
        d0_bignum_init(&temp);
        gmp_randinit_mt(RANDSTATE);
        gmp_randseed_ui(RANDSTATE, time(NULL));
+       * (time_t *) (&buf[0]) = time(0); // if everything else fails, we use the current time + uninitialized data
+#ifdef WIN32
+       {
+               HCRYPTPROV hCryptProv;
+               if(CryptAcquireContext(&hCryptProv, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT))
+               {
+                       if(!CryptGenRandom(hCryptProv, sizeof(buf), (PBYTE) &buf[0]))
+                               fprintf(stderr, "WARNING: could not initialize random number generator (CryptGenRandom failed)\n");
+               }
+               else
+                       fprintf(stderr, "WARNING: could not initialize random number generator (CryptAcquireContext failed)\n");
+       }
+#else
        f = fopen("/dev/urandom", "rb");
        if(!f)
                f = fopen("/dev/random", "rb");
        if(f)
        {
-               unsigned char buf[256];
                setbuf(f, NULL);
-               if(fread(buf, sizeof(buf), 1, f) == 1)
-               {
-                       mpz_import(temp.z, sizeof(buf), 1, 1, 0, 0, buf);
-                       gmp_randseed(RANDSTATE, temp.z);
-               }
+               if(fread(buf, sizeof(buf), 1, f) != 1)
+                       fprintf(stderr, "WARNING: could not initialize random number generator (read from random device failed)\n");
                fclose(f);
        }
+       else
+               fprintf(stderr, "WARNING: could not initialize random number generator (no random device found)\n");
+#endif
+
+       mpz_import(temp.z, sizeof(buf), 1, 1, 0, 0, buf);
+       gmp_randseed(RANDSTATE, temp.z);
 }
 
 void d0_bignum_SHUTDOWN(void)
index c71c88b..cc85624 100644 (file)
@@ -80,6 +80,8 @@ struct d0_blind_id_s
 
 #define CHECK(x) do { if(!(x)) goto fail; } while(0)
 #define CHECK_ASSIGN(var, value) do { d0_bignum_t *val; val = value; if(!val) goto fail; var = val; } while(0)
+#define MPCHECK(x) do { if(!failed) if(!(x)) failed = 1; } while(0)
+#define MPCHECK_ASSIGN(var, value) do { if(!failed) { d0_bignum_t *val; val = value; if(val) var = val; else failed = 1; } } while(0)
 
 #define USING(x) if(!(ctx->x)) return 0
 #define REPLACING(x)
@@ -712,6 +714,7 @@ WARN_UNUSED_RESULT BOOL d0_blind_id_authenticate_with_private_id_start(d0_blind_
        static unsigned char convbuf[1024];
        d0_iobuf_t *conv = NULL;
        size_t sz = 0;
+       BOOL failed = 0;
 
        // temps: temp0 order, temp0 4^r
        if(is_first)
@@ -736,14 +739,27 @@ WARN_UNUSED_RESULT BOOL d0_blind_id_authenticate_with_private_id_start(d0_blind_
        // generate random number r; x = g^r; send hash of x, remember r, forget x
        CHECK(d0_dl_get_order(temp0, ctx->schnorr_G));
        CHECK_ASSIGN(ctx->r, d0_bignum_rand_range(ctx->r, zero, temp0));
-       CHECK(d0_bignum_mod_pow(temp0, four, ctx->r, ctx->schnorr_G));
+       //CHECK(d0_bignum_mod_pow(temp0, four, ctx->r, ctx->schnorr_G));
 
        // initialize Signed Diffie Hellmann
-       CHECK(d0_dl_get_order(temp1, ctx->schnorr_G));
-       CHECK_ASSIGN(ctx->t, d0_bignum_rand_range(ctx->t, zero, temp1));
-       CHECK_ASSIGN(ctx->g_to_t, d0_bignum_mod_pow(ctx->g_to_t, four, ctx->t, ctx->schnorr_G));
+       // we already have the group order in temp1
+       CHECK_ASSIGN(ctx->t, d0_bignum_rand_range(ctx->t, zero, temp0));
        // can we SOMEHOW do this with just one mod_pow?
 
+#pragma omp parallel default(shared) reduction(||:failed)
+#pragma omp sections
+       {
+#pragma omp section
+               {
+                       MPCHECK(d0_bignum_mod_pow(temp0, four, ctx->r, ctx->schnorr_G));
+               }
+#pragma omp section
+               {
+                       MPCHECK_ASSIGN(ctx->g_to_t, d0_bignum_mod_pow(ctx->g_to_t, four, ctx->t, ctx->schnorr_G));
+               }
+       }
+       CHECK(!failed);
+
        // hash it, hash it, everybody hash it
        conv = d0_iobuf_open_write(convbuf, sizeof(convbuf));
        CHECK(d0_iobuf_write_bignum(conv, temp0));