FIDO_DEV_SET_IO_FUNCTIONS(3) | Library Functions Manual | FIDO_DEV_SET_IO_FUNCTIONS(3) |
fido_dev_set_io_functions
,
fido_dev_set_sigmask
,
fido_dev_set_timeout
,
fido_dev_set_transport_functions
,
fido_dev_io_handle
—
#include <fido.h>
typedef void *fido_dev_io_open_t(const char *); typedef void fido_dev_io_close_t(void *); typedef int fido_dev_io_read_t(void *, unsigned char *, size_t, int); typedef int fido_dev_io_write_t(void *, const unsigned char *, size_t); typedef struct fido_dev_io { fido_dev_io_open_t *open; fido_dev_io_close_t *close; fido_dev_io_read_t *read; fido_dev_io_write_t *write; } fido_dev_io_t; #ifdef _WIN32 typedef int fido_sigset_t; #else typedef sigset_t fido_sigset_t; #endif typedef int fido_dev_rx_t(struct fido_dev *, uint8_t, unsigned char *, size_t, int); typedef int fido_dev_tx_t(struct fido_dev *, uint8_t, const unsigned char *, size_t); typedef struct fido_dev_transport { fido_dev_rx_t *rx; fido_dev_tx_t *tx; } fido_dev_transport_t;
int
fido_dev_set_io_functions
(fido_dev_t
*dev, const fido_dev_io_t
*io);
int
fido_dev_set_sigmask
(fido_dev_t
*dev, const fido_sigset_t
*sigmask);
int
fido_dev_set_timeout
(fido_dev_t
*dev, int ms);
int
fido_dev_set_transport_functions
(fido_dev_t
*dev, const
fido_dev_transport_t *t);
void *
fido_dev_io_handle
(const
fido_dev_t *dev);
fido_dev_set_io_functions
() function sets the I/O
handlers used by libfido2 to talk to
dev. By default, these handlers are set to the operating
system's native HID or NFC interfaces. They are defined as follows:
When calling fido_dev_set_io_functions
(),
the open, close,
read, and write fields of
io may not be NULL.
No references to io are held by
fido_dev_set_io_functions
().
The fido_dev_set_sigmask
() function may be
used to specify a non-NULL signal mask sigmask to be
used while libfido2's default I/O handlers wait on
dev. On UNIX-like operating systems,
fido_sigset_t is defined as
sigset_t. On Windows,
fido_sigset_t is defined as int
and fido_dev_set_sigmask
() is a no-op.
No references to sigmask are held by
fido_dev_set_sigmask
().
The fido_dev_set_timeout
() function
informs libfido2 not to block for more than
ms milliseconds while communicating with
dev. If a timeout occurs, the corresponding
fido_dev_* function will fail with
FIDO_ERR_RX
. If ms is -1, then
libfido2 may block indefinitely. This is the default
behaviour. When using the Windows Hello backend, ms is
used as a guidance and may be overwritten by the platform.
The fido_dev_set_transport_functions
()
function sets the transport functions used by libfido2 to
talk to dev. While the I/O handlers are responsible
for sending and receiving transmission units of initialization and
continuation packets already formatted by libfido2, the
transport handlers are responsible for sending and receiving the CTAPHID
commands and data directly, as defined in the FIDO Client to Authenticator
Protocol (CTAP) standard. They are defined as follows:
When transport functions are specified, libfido2
will use them instead of the read
and
write
functions of the I/O handlers. However, the
I/O handlers must still be specified to open and close the device.
The fido_dev_io_handle
() function returns
the opaque pointer returned by the open
function of
the I/O handlers. This is useful mainly for the transport functions, which
unlike the I/O handlers are passed the fido_dev_t
pointer instead of the opaque I/O handle.
fido_dev_set_io_functions
(),
fido_dev_set_transport_functions
(),
fido_dev_set_sigmask
(), and
fido_dev_set_timeout
() return
FIDO_OK
. On error, a different error code defined in
<fido/err.h>
is returned.
Client to Authenticator Protocol (CTAP), https://fidoalliance.org/specs/fido-v2.1-ps-20210615/fido-client-to-authenticator-protocol-v2.1-ps-20210615.html, FIDO Alliance, 2021-06-15, Proposed Standard, Version 2.1.
May 25, 2018 | Yubico AB |