---
name: "shishi_dk"
section: "3"
platform: "linux"
package: "shishi-doc"
version: "1.0.3-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/shishi_dk"
---

# shishi\_dk(3)

API function

## NAME

shishi\_dk - API function

## SYNOPSIS

**#include \<shishi.h\>**

**int shishi\_dk(Shishi \*** *handle***, Shishi\_key \*** *key***, const char \*** *prfconstant***, size\_t** *prfconstantlen***, Shishi\_key \*** *derivedkey***);**

## ARGUMENTS

- Shishi \* handle

  shishi handle as allocated by **shishi\_init()**.

- Shishi\_key \* key

  input cryptographic key to use.

- const char \* prfconstant

  input array with the constant string.

- size\_t prfconstantlen

  size of input array with the constant string.

- Shishi\_key \* derivedkey

  pointer to derived key (allocated by caller).

## DERIVE A KEY FROM A KEY AND A CONSTANT THUSLY

DK(KEY, PRFCONSTANT) = SHISHI\_RANDOM-TO-KEY(SHISHI\_DR(KEY, PRFCONSTANT)).

## RETURN VALUE

Returns **SHISHI\_OK** iff successful.

## REPORTING BUGS

Report bugs to \<bug-shishi@gnu.org\>. GNU Shishi home page: http://www.gnu.org/software/shishi/ General help using GNU software: http://www.gnu.org/gethelp/

## COPYRIGHT

Copyright © 2002-2022 Simon Josefsson.\
 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.

## SEE ALSO

The full documentation for **shishi** is maintained as a Texinfo manual.  If the **info** and **shishi** programs are properly installed at your site, the command

-

  **info shishi**

should give you access to the complete manual.