fido_cred_exclude(3)

fido_cred_exclude3

Manage exclude lists in a fido2 credential

Usage

#include <fido.h>

int

fido_cred_exclude(fido_cred_t *cred, const unsigned char *ptr, size_t len);

int

fido_cred_empty_exclude_list(fido_cred_t *cred);

Overview

The fido_cred_exclude() function adds ptr to the list of credentials excluded by cred, where ptr points to a credential ID of len bytes. A copy of ptr is made, and no references to the passed pointer are kept. If fido_cred_exclude() fails, the existing list of excluded credentials is preserved.

If fido_cred_exclude returns success and cred is later passed to fido_dev_make_cred(3) on a device that contains the credential denoted by ptr, then fido_dev_make_cred(3) will fail.

For the format of a FIDO2 credential ID, please refer to the Web Authentication (webauthn) standard.

The fido_cred_empty_exclude_list() function empties the list of credentials excluded by cred.

Return values

The error codes returned by fido_cred_exclude() and fido_cred_empty_exclude_list() are defined in ⟨fido/err.h⟩. On success, FIDO_OK is returned.

Releases

4 releases since Debian 11 (Bullseye); the text changed 2 times.

  1. 11
  2. 12
  3. 13–Arch

From libfido2 1.17.0-1 in Arch Linux 2026-11-01. Parsed by carta from the page's mdoc source.