'\" t
.\"     Title: nvme-keys-gen-kxchap-secret
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 10/30/2026
.\"    Manual: NVMe Manual
.\"    Source: NVMe
.\"  Language: English
.\"
.TH "NVME\-KEYS\-GEN\-KXC" "1" "10/30/2026" "NVMe" "NVMe Manual"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
nvme-keys-gen-kxchap-secret \- Generate a host KX\-HMAC\-CHAP secret
.SH "SYNOPSIS"
.sp
.nf
\fInvme\fR [<global\-options>] \fIkeys gen\-kxchap\-secret\fR [\-\-hmac=<hmac\-id> | \-m <hmac\-id>]
                        [\-\-secret=<secret> | \-s <secret>]
                        [\-\-secret\-length=<len> | \-l <len>]
.fi
.SH "DESCRIPTION"
.sp
Generate a KX\-HMAC\-CHAP secret in the DHHC\-1 secret representation defined by the NVM Express Base Specification 2\&.4, section 8\&.3\&.4\&.5\&.8, in the form: DHHC\-1:00:ia6zGodOr4SEG0Zzaw398rpY0wqipUWj4jWjUh4HWUz6aQ2n: and prints it to stdout\&.
.SH "OPTIONS"
.PP
\-m <hmac\-id>, \-\-hmac=<hmac\-id>
.RS 4
Select the hash function the consumer is to apply to the secret\&. Possible values are: 0 \- No transformation (the secret is used as the key) 1 \- SHA\-256 2 \- SHA\-384 3 \- SHA\-512
.RE
.PP
\-s <secret>, \-\-secret=<secret>
.RS 4
Secret value (in hexadecimal) to be placed in the representation\&. If none are provided a random value is used\&.
.RE
.PP
\-l <len>, \-\-secret\-length=<len>
.RS 4
Length of the secret\&. Possible values are 32, 48, or 64\&. A secret given with
\fI\-\-secret\fR
as hexadecimal fixes the length, so a value contradicting it is an error; a secret generated here takes this length, defaulting to the digest size of the selected hash function, or 32 if none is selected\&.
.RE
.SH "GLOBAL OPTIONS"
.sp
The following options are defined at the top\-level nvme command and are available to this subcommand:
.PP
\-\-dry\-run
.RS 4
Print the command that would be executed, but do not actually execute it\&.
.RE
.PP
\-\-no\-ioctl\-probing
.RS 4
Disable probing for 64\-bit IOCTL support\&.
.RE
.PP
\-\-no\-retries
.RS 4
Disable retry logic on transient errors\&.
.RE
.PP
\-o <fmt>, \-\-output\-format=<fmt>
.RS 4
Set the reporting format to
\fInormal\fR,
\fItabular, \*(Aqjson\fR, or
\fIbinary\fR\&. Only one output format may be used at a time\&.
.RE
.PP
\-\-output\-format\-version=<version>
.RS 4
Select the output format version\&. Version
\fI1\fR
uses the original field naming, while version
\fI2\fR
(default) provides more consistent and script\-friendly field names\&. Other versions are rejected\&.
.RE
.PP
\-\-quiet
.RS 4
Suppress informational messages\&. Errors are still reported, and \-\-quiet cancels any \-\-verbose for the library log level\&.
.RE
.PP
\-\-set\-options=<key=value>[,<key=value>\&...]
.RS 4
Set libnvme library options for this invocation\&. Supported keys are
\fIforce\-4k\fR,
\fImi\-probe\-enabled\fR,
\fItest\-base\-dir\fR
and
\fItest\-sysfs\-dir\fR\&.
.RE
.PP
\-\-timeout=<ms>
.RS 4
Set the timeout for the command in milliseconds\&.
\fIinfinite\fR
or
\fI\-1\fR
waits without a time limit (0xffffffff)\&.
.RE
.PP
\-v, \-\-verbose
.RS 4
Increase the level of detail in the output\&. May be specified multiple times to further increase verbosity\&.
.RE
.sp
These options can also be set as machine\-wide defaults in nvme\-cli\&.conf(5)\&. A command\-line flag always overrides the file\&.
.SH "EXAMPLES"
.sp
No Examples
.SH "NVME"
.sp
Part of the nvme\-user suite