'\" t
.\"     Title: kcapi_pbkdf_iteration_count
.\"    Author: 
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: April 2024
.\"    Manual: Programming Interface
.\"    Source: libkcapi Manual 1.4.0
.\"  Language: English
.\"
.TH "KCAPI_PBKDF_ITERATIO" "3" "April 2024" "libkcapi Manual 1\&.4\&.0" "Programming Interface"
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.SH "NAME"
kcapi_pbkdf_iteration_count \- Calculate numbers of iterations for a PBKDF
.SH "SYNOPSIS"
.HP \w'uint32_t\ kcapi_pbkdf_iteration_count('u
.BI "uint32_t kcapi_pbkdf_iteration_count(const\ char\ *\ " "hashname" ", uint64_t\ " "timeshresh" ");"
.SH "ARGUMENTS"
.PP
\fIhashname\fR
.RS 4
[in] kernel crypto API name of a keyed hash (e\&.g\&. hmac(sha1))
.RE
.PP
\fItimeshresh\fR
.RS 4
[in] Time duration in nanoseconds that the PBKDF operation shall at least require\&. If that value is 0, a default of (1<<27) nanoseconds is used\&.
.RE
.SH "DESCRIPTION"
.PP
The function measures the time the PBKDF operation takes for different round counts for the given keyed message digest type\&.
.PP
The result should be taken as the iteration count for a PBKDF operation\&.
.PP
If an error occurs with the PBKDF calculation, a value of 1<<18 is returned\&.
.PP
\fIreturn\fR
number of iterations a PBKDF should take on this computer\&.
.SH "AUTHOR"
.PP
\fBStephan Mueller\fR <\&smueller@chronox.de\&>
.RS 4
Author.
.RE
.SH "COPYRIGHT"
.br