fix BN_mod_word and give a more reasonable return value if an error occurred

This commit is contained in:
Nils Larsch 2005-07-25 22:57:54 +00:00
parent 0537f9689c
commit 0260405c68
2 changed files with 12 additions and 5 deletions

View file

@ -69,6 +69,9 @@ BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w)
#endif
int i;
if (w == 0)
return (BN_ULONG)-1;
bn_check_top(a);
w&=BN_MASK2;
for (i=a->top-1; i>=0; i--)
@ -94,7 +97,7 @@ BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w)
if (!w)
/* actually this an error (division by zero) */
return 0;
return (BN_ULONG)-1;
if (a->top == 0)
return 0;
@ -102,7 +105,7 @@ BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w)
j = BN_BITS2 - BN_num_bits_word(w);
w <<= j;
if (!BN_lshift(a, a, j))
return 0;
return (BN_ULONG)-1;
for (i=a->top-1; i>=0; i--)
{

View file

@ -29,11 +29,11 @@ BN_add_word() adds B<w> to B<a> (C<a+=w>).
BN_sub_word() subtracts B<w> from B<a> (C<a-=w>).
BN_mul_word() multiplies B<a> and B<w> (C<a*=b>).
BN_mul_word() multiplies B<a> and B<w> (C<a*=w>).
BN_div_word() divides B<a> by B<w> (C<a/=w>) and returns the remainder.
BN_mod_word() returns the remainder of B<a> divided by B<w> (C<a%m>).
BN_mod_word() returns the remainder of B<a> divided by B<w> (C<a%w>).
For BN_div_word() and BN_mod_word(), B<w> must not be 0.
@ -42,7 +42,8 @@ For BN_div_word() and BN_mod_word(), B<w> must not be 0.
BN_add_word(), BN_sub_word() and BN_mul_word() return 1 for success, 0
on error. The error codes can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
BN_mod_word() and BN_div_word() return B<a>%B<w>.
BN_mod_word() and BN_div_word() return B<a>%B<w> on success and
B<(BN_ULONG)-1> if an error occurred.
=head1 SEE ALSO
@ -54,4 +55,7 @@ BN_add_word() and BN_mod_word() are available in all versions of
SSLeay and OpenSSL. BN_div_word() was added in SSLeay 0.8, and
BN_sub_word() and BN_mul_word() in SSLeay 0.9.0.
Before 0.9.8a the return value for BN_div_word() and BN_mod_word()
in case of an error was 0.
=cut