1=pod
2
3=head1 NAME
4
5BN_add_word, BN_sub_word, BN_mul_word, BN_div_word, BN_mod_word - arithmetic
6functions on BIGNUMs with integers
7
8=head1 SYNOPSIS
9
10 #include <openssl/bn.h>
11
12 int BN_add_word(BIGNUM *a, BN_ULONG w);
13
14 int BN_sub_word(BIGNUM *a, BN_ULONG w);
15
16 int BN_mul_word(BIGNUM *a, BN_ULONG w);
17
18 BN_ULONG BN_div_word(BIGNUM *a, BN_ULONG w);
19
20 BN_ULONG BN_mod_word(const BIGNUM *a, BN_ULONG w);
21
22=head1 DESCRIPTION
23
24These functions perform arithmetic operations on BIGNUMs with unsigned
25integers. They are much more efficient than the normal BIGNUM
26arithmetic operations.
27
28BN_add_word() adds B<w> to B<a> (C<a+=w>).
29
30BN_sub_word() subtracts B<w> from B<a> (C<a-=w>).
31
32BN_mul_word() multiplies B<a> and B<w> (C<a*=w>).
33
34BN_div_word() divides B<a> by B<w> (C<a/=w>) and returns the remainder.
35
36BN_mod_word() returns the remainder of B<a> divided by B<w> (C<a%w>).
37
38For BN_div_word() and BN_mod_word(), B<w> must not be 0.
39
40=head1 RETURN VALUES
41
42BN_add_word(), BN_sub_word() and BN_mul_word() return 1 for success, 0
43on error. The error codes can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
44
45BN_mod_word() and BN_div_word() return B<a>%B<w> on success and
46B<(BN_ULONG)-1> if an error occurred.
47
48=head1 SEE ALSO
49
50L<bn(3)|bn(3)>, L<ERR_get_error(3)|ERR_get_error(3)>, L<BN_add(3)|BN_add(3)>
51
52=head1 HISTORY
53
54BN_add_word() and BN_mod_word() are available in all versions of
55SSLeay and OpenSSL. BN_div_word() was added in SSLeay 0.8, and
56BN_sub_word() and BN_mul_word() in SSLeay 0.9.0.
57
58Before 0.9.8a the return value for BN_div_word() and BN_mod_word()
59in case of an error was 0.
60
61=cut
62