1*e71b7053SJung-uk Kim=pod 2*e71b7053SJung-uk Kim 3*e71b7053SJung-uk Kim=head1 NAME 4*e71b7053SJung-uk Kim 5*e71b7053SJung-uk KimBN_mod_inverse - compute inverse modulo n 6*e71b7053SJung-uk Kim 7*e71b7053SJung-uk Kim=head1 SYNOPSIS 8*e71b7053SJung-uk Kim 9*e71b7053SJung-uk Kim #include <openssl/bn.h> 10*e71b7053SJung-uk Kim 11*e71b7053SJung-uk Kim BIGNUM *BN_mod_inverse(BIGNUM *r, BIGNUM *a, const BIGNUM *n, 12*e71b7053SJung-uk Kim BN_CTX *ctx); 13*e71b7053SJung-uk Kim 14*e71b7053SJung-uk Kim=head1 DESCRIPTION 15*e71b7053SJung-uk Kim 16*e71b7053SJung-uk KimBN_mod_inverse() computes the inverse of B<a> modulo B<n> 17*e71b7053SJung-uk Kimplaces the result in B<r> (C<(a*r)%n==1>). If B<r> is NULL, 18*e71b7053SJung-uk Kima new B<BIGNUM> is created. 19*e71b7053SJung-uk Kim 20*e71b7053SJung-uk KimB<ctx> is a previously allocated B<BN_CTX> used for temporary 21*e71b7053SJung-uk Kimvariables. B<r> may be the same B<BIGNUM> as B<a> or B<n>. 22*e71b7053SJung-uk Kim 23*e71b7053SJung-uk Kim=head1 RETURN VALUES 24*e71b7053SJung-uk Kim 25*e71b7053SJung-uk KimBN_mod_inverse() returns the B<BIGNUM> containing the inverse, and 26*e71b7053SJung-uk KimNULL on error. The error codes can be obtained by L<ERR_get_error(3)>. 27*e71b7053SJung-uk Kim 28*e71b7053SJung-uk Kim=head1 SEE ALSO 29*e71b7053SJung-uk Kim 30*e71b7053SJung-uk KimL<ERR_get_error(3)>, L<BN_add(3)> 31*e71b7053SJung-uk Kim 32*e71b7053SJung-uk Kim=head1 COPYRIGHT 33*e71b7053SJung-uk Kim 34*e71b7053SJung-uk KimCopyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. 35*e71b7053SJung-uk Kim 36*e71b7053SJung-uk KimLicensed under the OpenSSL license (the "License"). You may not use 37*e71b7053SJung-uk Kimthis file except in compliance with the License. You can obtain a copy 38*e71b7053SJung-uk Kimin the file LICENSE in the source distribution or at 39*e71b7053SJung-uk KimL<https://www.openssl.org/source/license.html>. 40*e71b7053SJung-uk Kim 41*e71b7053SJung-uk Kim=cut 42