NAME

       fido_cred_new,   fido_cred_free,  fido_cred_fmt,  fido_cred_authdata_ptr,  fido_cred_clientdata_hash_ptr,
       fido_cred_id_ptr,  fido_cred_pubkey_ptr,  fido_cred_sig_ptr,  fido_cred_x5c_ptr,  fido_cred_authdata_len,
       fido_cred_clientdata_hash_len,       fido_cred_id_len,      fido_cred_pubkey_len,      fido_cred_sig_len,
       fido_cred_x5c_len — FIDO 2 credential API

SYNOPSIS

       #include <fido.h>

       fido_cred_t *
       fido_cred_new(void);

       void
       fido_cred_free(fido_cred_t **cred_p);

       const char *
       fido_cred_fmt(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_authdata_ptr(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_clientdata_hash_ptr(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_id_ptr(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_pubkey_ptr(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_sig_ptr(const fido_cred_t *cred);

       const unsigned char *
       fido_cred_x5c_ptr(const fido_cred_t *cred);

       size_t
       fido_cred_authdata_len(const fido_cred_t *cred);

       size_t
       fido_cred_clientdata_hash_len(const fido_cred_t *cred);

       size_t
       fido_cred_id_len(const fido_cred_t *cred);

       size_t
       fido_cred_pubkey_len(const fido_cred_t *cred);

       size_t
       fido_cred_sig_len(const fido_cred_t *cred);

       size_t
       fido_cred_x5c_len(const fido_cred_t *cred);

DESCRIPTION

       FIDO 2 credentials are abstracted in libfido2 by the fido_cred_t type.  The functions described  in  this
       page  allow  a  fido_cred_t  type  to  be allocated, deallocated, and inspected.  For other operations on
       fido_cred_t, please refer to fido_cred_set_authdata(3),  fido_cred_exclude(3),  fido_cred_verify(3),  and
       fido_dev_make_cred(3).

       The  fido_cred_new()  function returns a pointer to a newly allocated, empty fido_cred_t type.  If memory
       cannot be allocated, NULL is returned.

       The fido_cred_free() function  releases  the  memory  backing  *cred_p,  where  *cred_p  must  have  been
       previously  allocated  by  fido_cred_new().  On return, *cred_p is set to NULL.  Either cred_p or *cred_p
       may be NULL, in which case fido_cred_free() is a NOP.

       The fido_cred_fmt() function returns a pointer to a NUL-terminated string containing the format of  cred,
       or NULL if cred does not have a format set.

       The         fido_cred_authdata_ptr(),         fido_cred_clientdata_hash_ptr(),        fido_cred_id_ptr(),
       fido_cred_pubkey_ptr(), fido_cred_sig_ptr(), and fido_cred_x5c_ptr() functions  return  pointers  to  the
       authenticator  data,  client  data hash, ID, public key, signature and x509 certificate parts of cred, or
       NULL if the respective entry is not set.

       The corresponding length can be obtained  by  fido_cred_authdata_len(),  fido_cred_clientdata_hash_len(),
       fido_cred_id_len(), fido_cred_pubkey_len(), and fido_cred_sig_len().

       The  authenticator  data, x509 certificate, and signature parts of a credential are typically passed to a
       FIDO 2 server for verification.

RETURN VALUES

       The authenticator data returned by fido_cred_authdata_ptr() is a CBOR-encoded byte  string,  as  obtained
       from the authenticator.

       If      not     NULL,     pointers     returned     by     fido_cred_fmt(),     fido_cred_authdata_ptr(),
       fido_cred_clientdata_hash_ptr(),  fido_cred_id_ptr(),  fido_cred_pubkey_ptr(),  fido_cred_sig_ptr(),  and
       fido_cred_x5c_ptr()  are  guaranteed  to  exist  until any API function that takes cred without the const
       qualifier is invoked.

SEE ALSO

       fido_cred_exclude(3),   fido_cred_set_authdata(3),   fido_cred_verify(3),   fido_credman_metadata_new(3),
       fido_dev_make_cred(3)

Debian                                            May 23, 2018                                  FIDO_CRED_NEW(3)