---
name: "kcapi_md_setkey"
section: "3"
platform: "linux"
package: "libkcapi-dev"
version: "1.4.0-1+b2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/kcapi_md_setkey"
---

# kcapi\_md\_setkey(3)

set the key for the message digest handle

## NAME

kcapi\_md\_setkey - set the key for the message digest handle

## SYNOPSIS

**int kcapi\_md\_setkey(struct kcapi\_handle \*** *handle***, const uint8\_t \*** *key***, uint32\_t** *keylen***);**

## ARGUMENTS

*handle*

\[in\] cipher handle

*key*

\[in\] key buffer

*keylen*

\[in\] length of key buffer

## DESCRIPTION

With this function, the caller sets the key for subsequent hashing operations. This call is applicable for keyed message digests.

After the caller provided the key, the caller may securely destroy the key as it is now maintained by the kernel.

*return* 0 upon success; a negative errno-style error code if an error occurred

## AUTHOR

**Stephan Mueller** \<smueller@chronox.de\>

Author.

## COPYRIGHT