.\" DO NOT MODIFY THIS FILE!  It was generated by gdoc.
.TH "gnutls_x509_crq_get_key_id" 3 "3.6.7" "gnutls" "gnutls"
.SH NAME
gnutls_x509_crq_get_key_id \- API function
.SH SYNOPSIS
.B #include <gnutls/x509.h>
.sp
.BI "int gnutls_x509_crq_get_key_id(gnutls_x509_crq_t " crq ", unsigned int " flags ", unsigned char * " output_data ", size_t * " output_data_size ");"
.SH ARGUMENTS
.IP "gnutls_x509_crq_t crq" 12
a certificate of type \fBgnutls_x509_crq_t\fP
.IP "unsigned int flags" 12
should be one of the flags from \fBgnutls_keyid_flags_t\fP
.IP "unsigned char * output_data" 12
will contain the key ID
.IP "size_t * output_data_size" 12
holds the size of output_data (and will be
replaced by the actual size of parameters)
.SH "DESCRIPTION"
This function will return a unique ID that depends on the public key
parameters.  This ID can be used in checking whether a certificate
corresponds to the given private key.

If the buffer provided is not long enough to hold the output, then
* \fIoutput_data_size\fP is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
be returned.  The output will normally be a SHA\-1 hash output,
which is 20 bytes.
.SH "RETURNS"
In case of failure a negative error code will be
returned, and 0 on success.
.SH "SINCE"
2.8.0
.SH "REPORTING BUGS"
Report bugs to <bugs@gnutls.org>.
.br
Home page: https://www.gnutls.org

.SH COPYRIGHT
Copyright \(co 2001-2021 Free Software Foundation, Inc., and others.
.br
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.
.SH "SEE ALSO"
The full documentation for
.B gnutls
is maintained as a Texinfo manual.
If the /usr/share/doc/gnutls/
directory does not contain the HTML form visit
.B
.IP https://www.gnutls.org/manual/
.PP