1 // SPDX-License-Identifier: BSD-2-Clause
2 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
3  *
4  * LibTomCrypt is a library that provides various cryptographic
5  * algorithms in a highly modular and flexible manner.
6  *
7  * The library is free for all purposes without any express
8  * guarantee it works.
9  */
10 
11 /* The implementation is based on:
12  * "Salsa20 specification", http://cr.yp.to/snuffle/spec.pdf
13  * and salsa20-ref.c version 20051118
14  * Public domain from D. J. Bernstein
15  */
16 
17 #include "tomcrypt_private.h"
18 
19 #ifdef LTC_SALSA20
20 
21 /**
22   Generate a stream of random bytes via Salsa20
23   @param st      The Salsa20 state
24   @param out     [out] The output buffer
25   @param outlen  The output length
26   @return CRYPT_OK on success
27  */
salsa20_keystream(salsa20_state * st,unsigned char * out,unsigned long outlen)28 int salsa20_keystream(salsa20_state *st, unsigned char *out, unsigned long outlen)
29 {
30    if (outlen == 0) return CRYPT_OK; /* nothing to do */
31    LTC_ARGCHK(out != NULL);
32    XMEMSET(out, 0, outlen);
33    return salsa20_crypt(st, out, outlen, out);
34 }
35 
36 #endif
37 
38 /* ref:         $Format:%D$ */
39 /* git commit:  $Format:%H$ */
40 /* commit time: $Format:%ai$ */
41