fido_cbor_info_new,
fido_cbor_info_free,
fido_dev_get_cbor_info,
fido_cbor_info_aaguid_ptr,
fido_cbor_info_extensions_ptr,
fido_cbor_info_protocols_ptr,
fido_cbor_info_transports_ptr,
fido_cbor_info_versions_ptr,
fido_cbor_info_options_name_ptr,
fido_cbor_info_options_value_ptr,
fido_cbor_info_algorithm_type,
fido_cbor_info_algorithm_cose,
fido_cbor_info_algorithm_count,
fido_cbor_info_certs_name_ptr,
fido_cbor_info_certs_value_ptr,
fido_cbor_info_certs_len,
fido_cbor_info_aaguid_len,
fido_cbor_info_extensions_len,
fido_cbor_info_protocols_len,
fido_cbor_info_transports_len,
fido_cbor_info_versions_len,
fido_cbor_info_options_len,
fido_cbor_info_maxmsgsiz,
fido_cbor_info_maxcredbloblen,
fido_cbor_info_maxcredcntlst,
fido_cbor_info_maxcredidlen,
fido_cbor_info_maxlargeblob,
fido_cbor_info_maxrpid_minpinlen,
fido_cbor_info_minpinlen,
fido_cbor_info_fwversion,
fido_cbor_info_uv_attempts,
fido_cbor_info_uv_modality,
fido_cbor_info_rk_remaining,
fido_cbor_info_new_pin_required —
FIDO2 CBOR Info API
#include
<fido.h>
fido_cbor_info_t *
fido_cbor_info_new(
void);
void
fido_cbor_info_free(
fido_cbor_info_t
**ci_p);
int
fido_dev_get_cbor_info(
fido_dev_t
*dev,
fido_cbor_info_t
*ci);
const unsigned char *
fido_cbor_info_aaguid_ptr(
const
fido_cbor_info_t *ci);
char **
fido_cbor_info_extensions_ptr(
const
fido_cbor_info_t *ci);
const uint8_t *
fido_cbor_info_protocols_ptr(
const
fido_cbor_info_t *ci);
char **
fido_cbor_info_transports_ptr(
const
fido_cbor_info_t *ci);
char **
fido_cbor_info_versions_ptr(
const
fido_cbor_info_t *ci);
char **
fido_cbor_info_options_name_ptr(
const
fido_cbor_info_t *ci);
const bool *
fido_cbor_info_options_value_ptr(
const
fido_cbor_info_t *ci);
const char *
fido_cbor_info_algorithm_type(
const
fido_cbor_info_t *ci,
size_t idx);
int
fido_cbor_info_algorithm_cose(
const
fido_cbor_info_t *ci,
size_t idx);
size_t
fido_cbor_info_algorithm_count(
const
fido_cbor_info_t *ci);
char **
fido_cbor_info_certs_name_ptr(
const
fido_cbor_info_t *ci);
const uint64_t *
fido_cbor_info_certs_value_ptr(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_certs_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_aaguid_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_extensions_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_protocols_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_transports_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_versions_len(
const
fido_cbor_info_t *ci);
size_t
fido_cbor_info_options_len(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxmsgsiz(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxcredbloblen(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxcredcntlst(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxcredidlen(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxlargeblob(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_maxrpid_minpinlen(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_minpinlen(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_fwversion(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_uv_attempts(
const
fido_cbor_info_t *ci);
uint64_t
fido_cbor_info_uv_modality(
const
fido_cbor_info_t *ci);
int64_t
fido_cbor_info_rk_remaining(
const
fido_cbor_info_t *ci);
bool
fido_cbor_info_new_pin_required(
const
fido_cbor_info_t *ci);
The
fido_cbor_info_new() function returns a
pointer to a newly allocated, empty
fido_cbor_info_t type. If memory cannot be
allocated, NULL is returned.
The
fido_cbor_info_free() function releases
the memory backing
*ci_p, where
*ci_p must have been previously allocated by
fido_cbor_info_new(). On return,
*ci_p is set to NULL. Either
ci_p or
*ci_p may be NULL, in which case
fido_cbor_info_free() is a NOP.
The
fido_dev_get_cbor_info() function
transmits a
CTAP_CBOR_GETINFO command to
dev and fills
ci with attributes retrieved from the
command's response. The
fido_dev_get_cbor_info() function may
block.
The
fido_cbor_info_aaguid_ptr(),
fido_cbor_info_extensions_ptr(),
fido_cbor_info_protocols_ptr(),
fido_cbor_info_transports_ptr(), and
fido_cbor_info_versions_ptr() functions
return pointers to the authenticator attestation GUID, supported extensions,
PIN protocol, transports, and CTAP version strings of
ci. The corresponding length of a given
attribute can be obtained by
fido_cbor_info_aaguid_len(),
fido_cbor_info_extensions_len(),
fido_cbor_info_protocols_len(),
fido_cbor_info_transports_len(), or
fido_cbor_info_versions_len().
The
fido_cbor_info_options_name_ptr() and
fido_cbor_info_options_value_ptr()
functions return pointers to the array of option names and their respective
values in
ci. The length of the options array
is returned by
fido_cbor_info_options_len().
The
fido_cbor_info_algorithm_count() function
returns the number of supported algorithms in
ci. The
fido_cbor_info_algorithm_cose() function
returns the COSE identifier of algorithm
idx
in
ci, or 0 if the COSE identifier is unknown
or unset. The
fido_cbor_info_algorithm_type() function
returns the type of algorithm
idx in
ci, or NULL if the type is unset. Please note
that the first algorithm in
ci has an
idx (index) value of 0.
The
fido_cbor_info_certs_name_ptr() and
fido_cbor_info_certs_value_ptr() functions
return pointers to the array of certification names and their respective
values in
ci. The length of the
certifications array is returned by
fido_cbor_info_certs_len().
The
fido_cbor_info_maxmsgsiz() function
returns the maximum message size attribute of
ci.
The
fido_cbor_info_maxcredbloblen() function
returns the maximum “credBlob” length in bytes supported by the
authenticator as reported in
ci.
The
fido_cbor_info_maxcredcntlst() function
returns the maximum supported number of credentials in a single credential ID
list as reported in
ci.
The
fido_cbor_info_maxcredidlen() function
returns the maximum supported length of a credential ID as reported in
ci.
The
fido_cbor_info_maxrpid_minpinlen()
function returns the maximum number of RP IDs that may be passed to
fido_dev_set_pin_minlen_rpid(3),
as reported in
ci. The minimum PIN length
attribute is a CTAP 2.1 addition. If the attribute is not advertised by the
authenticator, the
fido_cbor_info_maxrpid_minpinlen() function
returns zero.
The
fido_cbor_info_maxlargeblob() function
returns the maximum length in bytes of an authenticator's serialized largeBlob
array as reported in
ci.
The
fido_cbor_info_minpinlen() function
returns the minimum PIN length enforced by the authenticator as reported in
ci. The minimum PIN length attribute is a
CTAP 2.1 addition. If the attribute is not advertised by the authenticator,
the
fido_cbor_info_minpinlen() function
returns zero.
The
fido_cbor_info_fwversion() function
returns the firmware version attribute of
ci.
The
fido_cbor_info_uv_attempts() function
returns the number of UV attempts that the platform may attempt before falling
back to PIN authentication. If 1, then all
fido_dev_get_uv_retry_count(3)
retries are handled internally by the authenticator and the platform may only
attempt non-PIN UV once. The UV attempts attribute is a CTAP 2.1 addition. If
the attribute is not advertised by the authenticator, the
fido_cbor_info_uv_attempts() function
returns zero.
The
fido_cbor_info_uv_modality() function
returns a bitmask representing different UV modes supported by the
authenticator, as defined in the FIDO Registry of Predefined Values and
reported in
ci. See the
FIDO_UV_MODE_* definitions in
<fido/param.h>
for the set of values defined by libfido2 and a brief description of each. The
UV modality attribute is a CTAP 2.1 addition. If the attribute is not
advertised by the authenticator, the
fido_cbor_info_uv_modality() function
returns zero.
The
fido_cbor_info_rk_remaining() function
returns the estimated number of additional resident/discoverable credentials
that can be stored on the authenticator as reported in
ci. The estimated number of remaining
resident credentials is a CTAP 2.1 addition. If the attribute is not
advertised by the authenticator, the
fido_cbor_info_rk_remaining() function
returns -1.
The
fido_cbor_info_new_pin_required()
function returns whether a new PIN is required by the authenticator as
reported in
ci. If
fido_cbor_info_new_pin_required() returns
true, operations requiring PIN authentication will fail until a new PIN is set
on the authenticator. The
fido_dev_set_pin(3)
function can be used to set a new PIN.
A complete example of how to use these functions can be found in the
example/info.c file shipped with
libfido2.
The
fido_cbor_info_aaguid_ptr(),
fido_cbor_info_extensions_ptr(),
fido_cbor_info_protocols_ptr(),
fido_cbor_info_transports_ptr(),
fido_cbor_info_versions_ptr(),
fido_cbor_info_options_name_ptr(), and
fido_cbor_info_options_value_ptr()
functions return NULL if the respective field in
ci is absent. If not NULL, returned pointers
are guaranteed to exist until any API function that takes
ci without the
const qualifier is invoked.
fido_dev_get_uv_retry_count(3),
fido_dev_open(3),
fido_dev_set_pin(3),
fido_dev_set_pin_minlen_rpid(3)
FIDO Registry of Predefined
Values,
https://fidoalliance.org/specs/common-specs/fido-registry-v2.2-rd-20210525.html,
FIDO Alliance, 2021-05-25,
Review Draft, Version 2.2.
