un-debianize libd0_blind_id's RNG on Win32

[xonotic/d0_blind_id.git] / d0_bignum-gmp.c

diff --git a/d0_bignum-gmp.c b/d0_bignum-gmp.c
index 6a2f703e2d69796903fd198d95e2de6f25bfd05e..5f0babc088f82423946ab22e4d8142cb67760be6 100644 (file)
--- a/d0_bignum-gmp.c
+++ b/d0_bignum-gmp.c
@@ -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)