Commit cf9056cf authored by Geoff Thorpe's avatar Geoff Thorpe
Browse files

BN_div_word() was breaking when called from BN_bn2dec() (actually, this is 

the only function that uses it) because it would trip up an assertion in
bn_div_words() when first invoked. This also adds BN_div_word() testing to
bntest.

Submitted by: Nils Larsch
Reviewed by: Geoff Thorpe
parent f7fc4ca1

crypto/bn/bn_word.c

+8 −1
Original line number Diff line number Diff line
@@ -87,7 +87,7 @@ BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w) 
BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w)

	{

	BN_ULONG ret = 0;

	int i;

	int i, j;



	bn_check_top(a);

	w &= BN_MASK2;
@@ -98,6 +98,12 @@ BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w) 
	if (a->top == 0)

		return 0;



	/* normalize input (so bn_div_words doesn't complain) */

	j = BN_BITS2 - BN_num_bits_word(w);

	w <<= j;

	if (!BN_lshift(a, a, j))

		return 0;



	for (i=a->top-1; i>=0; i--)

		{

		BN_ULONG l,d;
@@ -109,6 +115,7 @@ BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w) 
		}

	if ((a->top > 0) && (a->d[a->top-1] == 0))

		a->top--;

	ret >>= j;

	bn_check_top(a);

	return(ret);

	}

crypto/bn/bntest.c

+61 −0
Original line number Diff line number Diff line
@@ -98,6 +98,7 @@ int test_lshift(BIO *bp,BN_CTX *ctx,BIGNUM *a_); 
int test_rshift1(BIO *bp);

int test_rshift(BIO *bp,BN_CTX *ctx);

int test_div(BIO *bp,BN_CTX *ctx);

int test_div_word(BIO *bp);

int test_div_recp(BIO *bp,BN_CTX *ctx);

int test_mul(BIO *bp);

int test_sqr(BIO *bp,BN_CTX *ctx);
@@ -221,6 +222,10 @@ int main(int argc, char *argv[]) 
	if (!test_div(out,ctx)) goto err;

	BIO_flush(out);



	message(out,"BN_div_word");

	if (!test_div_word(out)) goto err;

	BIO_flush(out);



	message(out,"BN_div_recp");

	if (!test_div_recp(out,ctx)) goto err;

	BIO_flush(out);
@@ -463,6 +468,62 @@ int test_div(BIO *bp, BN_CTX *ctx) 
	return(1);

	}



int test_div_word(BIO *bp)

	{

	BIGNUM   a,b;

	BN_ULONG r,s;

	int i;



	BN_init(&a);

	BN_init(&b);



	for (i=0; i<num0; i++)

		{

		do {

			BN_bntest_rand(&a,512,-1,0);

			BN_bntest_rand(&b,BN_BITS2,-1,0);

			s = b.d[0];

		} while (!s);



		BN_copy(&b, &a);

		r = BN_div_word(&b, s);



		if (bp != NULL)

			{

			if (!results)

				{

				BN_print(bp,&a);

				BIO_puts(bp," / ");

				BIO_printf(bp,"%lX",s);

				BIO_puts(bp," - ");

				}

			BN_print(bp,&b);

			BIO_puts(bp,"\n");



			if (!results)

				{

				BN_print(bp,&a);

				BIO_puts(bp," % ");

				BIO_printf(bp,"%lX",s);

				BIO_puts(bp," - ");

				}

			BIO_printf(bp,"%lX",r);

			BIO_puts(bp,"\n");

			}

		BN_mul_word(&b,s);

		BN_add_word(&b,r);

		BN_sub(&b,&a,&b);

		if(!BN_is_zero(&b))

		    {

		    fprintf(stderr,"Division (word) test failed!\n");

		    return 0;

		    }

		}

	BN_free(&a);

	BN_free(&b);

	return(1);

	}



int test_div_recp(BIO *bp, BN_CTX *ctx)

	{

	BIGNUM a,b,c,d,e;