NAME
BN_mod_inverse
—
compute inverse modulo n
SYNOPSIS
#include
<openssl/bn.h>
BIGNUM *
BN_mod_inverse
(BIGNUM *r,
BIGNUM *a, const BIGNUM *n,
BN_CTX *ctx);
DESCRIPTION
BN_mod_inverse
()
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.
ctx is a previously allocated BN_CTX used for temporary variables. r may be the same BIGNUM as a or n.
RETURN VALUES
BN_mod_inverse
() returns the
BIGNUM containing the inverse, or
NULL
on error. The error codes can be obtained by
ERR_get_error(3).
SEE ALSO
HISTORY
BN_mod_inverse
() is available in all
versions of SSLeay and OpenSSL.