Speed up DH with small generator. (6dad7bd6) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP OpenSSL

CHANGES

+5 −0

Original line number	Diff line number	Diff line
		@@ -4,6 +4,11 @@

		Changes between 0.9.5a and 0.9.6 [xx XXX 2000]

		*) New function BN_mod_exp_mont_word for small bases (roughly 20%
		faster than BN_mod_exp_mont even though it does not use
		windowing).
		[Bodo Moeller]

		*) CygWin32 support.
		[John Jarvie <jjarvie@newsguy.com>]

crypto/bn/bn.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -364,6 +364,8 @@ int BN_mod_exp(BIGNUM r, BIGNUM a, const BIGNUM *p,
		const BIGNUM m,BN_CTX ctx);
		int BN_mod_exp_mont(BIGNUM r, BIGNUM a, const BIGNUM *p,
		const BIGNUM m, BN_CTX ctx, BN_MONT_CTX *m_ctx);
		int BN_mod_exp_mont_word(BIGNUM r, BN_ULONG a, const BIGNUM p,
		const BIGNUM m, BN_CTX ctx, BN_MONT_CTX *m_ctx);
		int BN_mod_exp2_mont(BIGNUM r, BIGNUM a1, BIGNUM p1,BIGNUM a2,
		BIGNUM p2,BIGNUM m,BN_CTX ctx,BN_MONT_CTX m_ctx);
		int BN_mod_exp_simple(BIGNUM r, BIGNUM a, BIGNUM *p,
		@@ -484,6 +486,7 @@ BN_ULONG bn_sub_words(BN_ULONG rp, BN_ULONG ap, BN_ULONG *bp,int num);
		#define BN_F_BN_DIV 107
		#define BN_F_BN_EXPAND2 108
		#define BN_F_BN_MOD_EXP_MONT 109
		#define BN_F_BN_MOD_EXP_MONT_WORD 117
		#define BN_F_BN_MOD_INVERSE 110
		#define BN_F_BN_MOD_MUL_RECIPROCAL 111
		#define BN_F_BN_MPI2BN 112

crypto/bn/bn_err.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -77,6 +77,7 @@ static ERR_STRING_DATA BN_str_functs[]=
		{ERR_PACK(0,BN_F_BN_DIV,0), "BN_div"},
		{ERR_PACK(0,BN_F_BN_EXPAND2,0), "bn_expand2"},
		{ERR_PACK(0,BN_F_BN_MOD_EXP_MONT,0), "BN_mod_exp_mont"},
		{ERR_PACK(0,BN_F_BN_MOD_EXP_MONT_WORD,0), "BN_MOD_EXP_MONT_WORD"},
		{ERR_PACK(0,BN_F_BN_MOD_INVERSE,0), "BN_mod_inverse"},
		{ERR_PACK(0,BN_F_BN_MOD_MUL_RECIPROCAL,0), "BN_mod_mul_reciprocal"},
		{ERR_PACK(0,BN_F_BN_MPI2BN,0), "BN_mpi2bn"},

crypto/bn/bn_exp.c

+93 −45

Original line number	Diff line number	Diff line
		@@ -66,6 +66,7 @@
		# include <dlfcn.h>
		#endif


		#define TABLE_SIZE 16

		/* slow but works */
		@@ -91,42 +92,6 @@ err:
		return(r);
		}

		#if 0
		/* this one works - simple but works */
		int BN_mod_exp(BIGNUM r, BIGNUM a, BIGNUM p, BIGNUM m, BN_CTX *ctx)
		{
		int i,bits,ret=0;
		BIGNUM v,tmp;

		BN_CTX_start(ctx);
		v = BN_CTX_get(ctx);
		tmp = BN_CTX_get(ctx);
		if (v == NULL \|\| tmp == NULL) goto err;

		if (BN_copy(v,a) == NULL) goto err;
		bits=BN_num_bits(p);

		if (BN_is_odd(p))
		{ if (BN_copy(r,a) == NULL) goto err; }
		else { if (!BN_one(r)) goto err; }

		for (i=1; i<bits; i++)
		{
		if (!BN_sqr(tmp,v,ctx)) goto err;
		if (!BN_mod(v,tmp,m,ctx)) goto err;
		if (BN_is_bit_set(p,i))
		{
		if (!BN_mul(tmp,r,v,ctx)) goto err;
		if (!BN_mod(r,tmp,m,ctx)) goto err;
		}
		}
		ret=1;
		err:
		BN_CTX_end(ctx);
		return(ret);
		}

		#endif

		/* this one works - simple but works */
		int BN_exp(BIGNUM r, BIGNUM a, BIGNUM p, BN_CTX ctx)
		@@ -163,6 +128,7 @@ err:
		return(ret);
		}


		#ifdef ATALLA

		/*
		@@ -330,6 +296,7 @@ int BN_mod_exp_atalla(BIGNUM r, BIGNUM a, const BIGNUM p, const BIGNUM m)
		}
		#endif /* def ATALLA */


		int BN_mod_exp(BIGNUM r, BIGNUM a, const BIGNUM p, const BIGNUM m,
		BN_CTX *ctx)
		{
		@@ -354,7 +321,15 @@ int BN_mod_exp(BIGNUM r, BIGNUM a, const BIGNUM p, const BIGNUM m,
		/* if ((m->d[m->top-1]&BN_TBIT) && BN_is_odd(m)) */

		if (BN_is_odd(m))
		{ ret=BN_mod_exp_mont(r,a,p,m,ctx,NULL); }
		{
		if (a->top == 1)
		{
		BN_ULONG A = a->d[0];
		ret=BN_mod_exp_mont_word(r,A,p,m,ctx,NULL);
		}
		else
		ret=BN_mod_exp_mont(r,a,p,m,ctx,NULL);
		}
		else
		#endif
		#ifdef RECP_MUL_MOD
		@@ -370,7 +345,7 @@ int BN_mod_exp(BIGNUM r, BIGNUM a, const BIGNUM p, const BIGNUM m,
		return(ret);
		}

		/* #ifdef RECP_MUL_MOD */

		int BN_mod_exp_recp(BIGNUM r, const BIGNUM a, const BIGNUM *p,
		const BIGNUM m, BN_CTX ctx)
		{
		@@ -485,9 +460,8 @@ err:
		BN_RECP_CTX_free(&recp);
		return(ret);
		}
		/* #endif */

		/* #ifdef MONT_MUL_MOD */

		int BN_mod_exp_mont(BIGNUM rr, BIGNUM a, const BIGNUM *p,
		const BIGNUM m, BN_CTX ctx, BN_MONT_CTX *in_mont)
		{
		@@ -527,11 +501,9 @@ int BN_mod_exp_mont(BIGNUM rr, BIGNUM a, const BIGNUM *p,
		/* If this is not done, things will break in the montgomery
		* part */

		#if 1
		if (in_mont != NULL)
		mont=in_mont;
		else
		#endif
		{
		if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
		if (!BN_MONT_CTX_set(mont,m,ctx)) goto err;
		@@ -541,7 +513,8 @@ int BN_mod_exp_mont(BIGNUM rr, BIGNUM a, const BIGNUM *p,
		ts=1;
		if (BN_ucmp(a,m) >= 0)
		{
		BN_mod(&(val[0]),a,m,ctx);
		if (!BN_mod(&(val[0]),a,m,ctx))
		goto err;
		aa= &(val[0]);
		}
		else
		@@ -635,7 +608,82 @@ err:
		BN_clear_free(&(val[i]));
		return(ret);
		}
		/* #endif */

		int BN_mod_exp_mont_word(BIGNUM rr, BN_ULONG a, const BIGNUM p,
		const BIGNUM m, BN_CTX ctx, BN_MONT_CTX *in_mont)
		/* if we had BN_mod_exp_mont_2, we could even use windowing in it */
		{
		int b, bits, ret=0;
		BIGNUM d, r, *t;
		BN_MONT_CTX *mont = NULL;

		bn_check_top(p);
		bn_check_top(m);

		if (!(m->d[0] & 1))
		{
		BNerr(BN_F_BN_MOD_EXP_MONT_WORD,BN_R_CALLED_WITH_EVEN_MODULUS);
		return(0);
		}
		bits = BN_num_bits(p);
		if (bits == 0)
		{
		BN_one(rr);
		return(1);
		}
		BN_CTX_start(ctx);
		d = BN_CTX_get(ctx);
		r = BN_CTX_get(ctx);
		t = BN_CTX_get(ctx);
		if (d == NULL \|\| r == NULL \|\| t == NULL) goto err;

		#ifdef ATALLA
		if (!tried_atalla)
		{
		BN_set_word(t, a);
		if (BN_mod_exp_word_atalla(rr, t, p, m))
		return 1;
		}
		/* If it fails, try the other methods */
		#endif

		if (in_mont != NULL)
		mont=in_mont;
		else
		{
		if ((mont = BN_MONT_CTX_new()) == NULL) goto err;
		if (!BN_MONT_CTX_set(mont, m, ctx)) goto err;
		}

		if (!BN_to_montgomery(r, BN_value_one(), mont, ctx)) goto err;
		for (b = bits-1; b >= 0; b--)
		{
		if (BN_is_bit_set(p, b))
		{
		if (!BN_mul_word(r, a))
		goto err;
		if (BN_ucmp(r, m) >= 0)
		{
		if (!BN_mod(t, r, m, ctx))
		goto err;
		{ BIGNUM *swap_tmp = r; r = t; t = swap_tmp; }
		}
		}

		if (b > 0)
		{
		if (!BN_mod_mul_montgomery(r, r, r, mont, ctx))
		goto err;
		}
		}
		BN_from_montgomery(rr, r, mont, ctx);
		ret = 1;
		err:
		if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont);
		BN_CTX_end(ctx);
		return(ret);
		}


		/* The old fallback, simple version :-) */
		int BN_mod_exp_simple(BIGNUM r, BIGNUM a, BIGNUM p, BIGNUM m,

crypto/dh/dh_key.c

+14 −7

Original line number	Diff line number	Diff line
		@@ -194,9 +194,16 @@ static int dh_bn_mod_exp(DH dh, BIGNUM r, BIGNUM a, const BIGNUM p,
		const BIGNUM m, BN_CTX ctx,
		BN_MONT_CTX *m_ctx)
		{
		if (a->top == 1)
		{
		BN_ULONG A = a->d[0];
		return BN_mod_exp_mont_word(r,A,p,m,ctx,m_ctx);
		}
		else
		return BN_mod_exp_mont(r,a,p,m,ctx,m_ctx);
		}


		static int dh_init(DH *dh)
		{
		dh->flags \|= DH_FLAG_CACHE_MONT_P;