NAME

       shishi_encrypt_ivupdate - API function

SYNOPSIS

       #include <shishi.h>

       int  shishi_encrypt_ivupdate(Shishi  *  handle,  Shishi_key  * key, int keyusage, const char * iv, size_t
       ivlen, char ** ivout, size_t * ivoutlen, const char * in, size_t inlen, char ** out, size_t * outlen);

ARGUMENTS

       Shishi * handle
                   shishi handle as allocated by shishi_init().

       Shishi_key * key
                   key to encrypt with.

       int keyusage
                   integer specifying what this key is encrypting.

       const char * iv
                   input array with initialization vector

       size_t ivlen
                   size of input array with initialization vector.

       char ** ivout
                   output array with newly allocated updated initialization vector.

       size_t * ivoutlen
                   size of output array with updated initialization vector.

       const char * in
                   input array with data to encrypt.

       size_t inlen
                   size of input array with data to encrypt.

       char ** out output array with newly allocated encrypted data.

       size_t * outlen
                   output variable with size of newly allocated output array.

DESCRIPTION

       Encrypts data using specified initialization vector and key.  The key actually used is derived using  the
       key  usage.   If  key  usage  is 0, no key derivation is used.  The OUT buffer must be deallocated by the
       caller.  If IVOUT or IVOUTLEN is NULL, the updated IV is not saved anywhere.

       Note that DECRYPT(ENCRYPT(data)) does not necessarily yield data exactly.  Some encryption types add  pad
       to  make  the  data  fit  into  the  block size of the encryption algorithm.  Furthermore, the pad is not
       guaranteed to look in any special way, although existing implementations often pad with  the  zero  byte.
       This  means  that  you  may  have  to  "frame" data, so it is possible to infer the original length after
       decryption.  Compare ASN.1 DER which contains such information.

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.