bn_mod_inverse(3) - Linux man page
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 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, and NULL on error. The error codes can be obtained by err_get_error(3).
See Also
bn(3), err_get_error(3), bn_add(3)
History
BN_mod_inverse() is available in all versions of SSLeay and OpenSSL.