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]

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

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

RETURN VALUES    [Toc]    [Back]

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

HISTORY    [Toc]    [Back]

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

SEE ALSO    [Toc]    [Back]

       Functions: bn(3), err(3), BN_add(3)



                                                BN_mod_inverse(3)