Add a method to generate a prime that is guaranteed not to be divisible by 3 or 5. (b0513819) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP OpenSSL

apps/speed.c

+23 −0

Original line number	Diff line number	Diff line
		@@ -2042,6 +2042,29 @@ int MAIN(int argc, char **argv)

		}

		if (prime_doit[D_PRIME_COPRIME])
		{
		BIGNUM *rnd = BN_new();
		BIGNUM *add = BN_new();
		BN_CTX *ctx = BN_CTX_new();

		BN_set_word(add, 2);
		prime_print_message(prime_names[D_PRIME_COPRIME],
		prime_c[D_PRIME_COPRIME]);

		Time_F(START);
		for (count=0, run=1; COND(prime_c[D_PRIME_COPRIME]); count++)
		bn_probable_prime_dh_coprime(rnd, 1024, add, NULL, ctx);

		d=Time_F(STOP);
		prime_print_result(D_PRIME_COPRIME, count, d);

		BN_CTX_free(ctx);
		BN_free(add);
		BN_free(rnd);

		}

		RAND_pseudo_bytes(buf,36);
		#ifndef OPENSSL_NO_RSA
		for (j=0; j<RSA_NUM; j++)

crypto/bn/bn_lcl.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -536,6 +536,8 @@ BIGNUM int_bn_mod_inverse(BIGNUM in,

		int bn_probable_prime_dh(BIGNUM *rnd, int bits,
		const BIGNUM add, const BIGNUM rem, BN_CTX *ctx);
		int bn_probable_prime_dh_coprime(BIGNUM *rnd, int bits,
		const BIGNUM add, const BIGNUM rem, BN_CTX *ctx);

		#ifdef __cplusplus
		}

crypto/bn/bn_prime.c

+55 −29

Original line number	Diff line number	Diff line
		@@ -129,9 +129,13 @@
		static int witness(BIGNUM w, const BIGNUM a, const BIGNUM *a1,
		const BIGNUM a1_odd, int k, BN_CTX ctx, BN_MONT_CTX *mont);
		static int probable_prime(BIGNUM *rnd, int bits);
		static int probable_prime_dh(BIGNUM rnd, const BIGNUM add,
		const BIGNUM rem, BN_CTX ctx, int first_prime_index);
		static int probable_prime_dh_safe(BIGNUM *rnd, int bits,
		const BIGNUM add, const BIGNUM rem, BN_CTX *ctx);

		static int prime_offsets[8] = { 7, 11, 13, 17, 19, 23, 29, 31 };

		int BN_GENCB_call(BN_GENCB *cb, int a, int b)
		{
		/* No callback means continue */
		@@ -363,40 +367,25 @@ err:
		int bn_probable_prime_dh(BIGNUM *rnd, int bits,
		const BIGNUM add, const BIGNUM rem, BN_CTX *ctx)
		{
		int i,ret=0;
		BIGNUM *t1;
		if (!BN_rand(rnd, bits, 0, 1)) return(0);

		BN_CTX_start(ctx);
		if ((t1 = BN_CTX_get(ctx)) == NULL) goto err;
		return(probable_prime_dh(rnd, add, rem, ctx, 1));
		}

		if (!BN_rand(rnd,bits,0,1)) goto err;
		int bn_probable_prime_dh_coprime(BIGNUM *rnd, int bits,
		const BIGNUM add, const BIGNUM rem, BN_CTX *ctx)
		{
		BIGNUM *offset_index = BN_new();

		/* we need ((rnd-rem) % add) == 0 */
		if (!BN_rand(rnd, bits, 0, 1)) return(0);
		if (!BN_rand(offset_index, 3, -1, -1)) return(0);

		if (!BN_mod(t1,rnd,add,ctx)) goto err;
		if (!BN_sub(rnd,rnd,t1)) goto err;
		if (rem == NULL)
		{ if (!BN_add_word(rnd,1)) goto err; }
		else
		{ if (!BN_add(rnd,rnd,rem)) goto err; }
		BN_mul_word(rnd, 30);
		BN_add_word(rnd, prime_offsets[BN_get_word(offset_index)]);

		/* we now have a random number 'rand' to test. */
		BN_free(offset_index);

		loop:
		for (i=1; i<NUMPRIMES; i++)
		{
		/* check that rnd is a prime */
		if (BN_mod_word(rnd,(BN_ULONG)primes[i]) <= 1)
		{
		if (!BN_add(rnd,rnd,add)) goto err;
		goto loop;
		}
		}
		ret=1;
		err:
		BN_CTX_end(ctx);
		bn_check_top(rnd);
		return(ret);
		return(probable_prime_dh(rnd, add, rem, ctx, 3));
		}

		static int witness(BIGNUM w, const BIGNUM a, const BIGNUM *a1,
		@@ -491,6 +480,43 @@ loop:
		return(1);
		}

		static int probable_prime_dh(BIGNUM rnd, const BIGNUM add,
		const BIGNUM rem, BN_CTX ctx, int first_prime_index)
		{
		int i,ret=0;
		BIGNUM *t1;

		BN_CTX_start(ctx);
		if ((t1 = BN_CTX_get(ctx)) == NULL) goto err;

		/* we need ((rnd-rem) % add) == 0 */

		if (!BN_mod(t1,rnd,add,ctx)) goto err;
		if (!BN_sub(rnd,rnd,t1)) goto err;
		if (rem == NULL)
		{ if (!BN_add_word(rnd,1)) goto err; }
		else
		{ if (!BN_add(rnd,rnd,rem)) goto err; }

		/* we now have a random number 'rand' to test. */

		loop:
		for (i=first_prime_index; i<NUMPRIMES; i++)
		{
		/* check that rnd is a prime */
		if (BN_mod_word(rnd,(BN_ULONG)primes[i]) <= 1)
		{
		if (!BN_add(rnd,rnd,add)) goto err;
		goto loop;
		}
		}
		ret=1;
		err:
		BN_CTX_end(ctx);
		bn_check_top(rnd);
		return(ret);
		}

		static int probable_prime_dh_safe(BIGNUM p, int bits, const BIGNUM padd,
		const BIGNUM rem, BN_CTX ctx)
		{