NAME    [Toc]    [Back]

       BN_mod_inverse - compute inverse modulo n

SYNOPSIS    [Toc]    [Back]

        #include <openssl/bn.h>

        BIGNUM *BN_mod_inverse(BIGNUM *r, BIGNUM *a, const BIGNUM
*n,
                  BN_CTX *ctx);

DESCRIPTION    [Toc]    [Back]

       BN_mod_inverse() computes the inverse of a modulo n places
       the result in r ("(a*r)%n==1"). If r is NULL, a new BIGNUM
       is created.

       ctx is a previously allocated BN_CTX used for temporary
       variables. r may be the same BIGNUM as a or n.

RETURN VALUES    [Toc]    [Back]

       BN_mod_inverse() returns the BIGNUM containing the
       inverse, and NULL on error. The error codes can be
       obtained by ERR_get_error(3).

SEE ALSO    [Toc]    [Back]

       bn(3), ERR_get_error(3), BN_add(3)

HISTORY    [Toc]    [Back]

       BN_mod_inverse() is available in all versions of SSLeay
       and OpenSSL.


OpenBSD 3.6                 2000-04-03                          1