diff options
Diffstat (limited to 'crypto/openssh/openbsd-compat/bsd-arc4random.c')
-rw-r--r-- | crypto/openssh/openbsd-compat/bsd-arc4random.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/crypto/openssh/openbsd-compat/bsd-arc4random.c b/crypto/openssh/openbsd-compat/bsd-arc4random.c new file mode 100644 index 0000000..ab4e143 --- /dev/null +++ b/crypto/openssh/openbsd-compat/bsd-arc4random.c @@ -0,0 +1,77 @@ +/* + * Copyright (c) 1999-2000 Damien Miller. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "includes.h" +#include "log.h" + +RCSID("$Id: bsd-arc4random.c,v 1.5 2002/05/08 22:57:18 tim Exp $"); + +#ifndef HAVE_ARC4RANDOM + +#include <openssl/rand.h> +#include <openssl/rc4.h> +#include <openssl/err.h> + +/* Size of key to use */ +#define SEED_SIZE 20 + +/* Number of bytes to reseed after */ +#define REKEY_BYTES (1 << 24) + +static int rc4_ready = 0; +static RC4_KEY rc4; + +unsigned int arc4random(void) +{ + unsigned int r = 0; + static int first_time = 1; + + if (rc4_ready <= 0) { + if (first_time) + seed_rng(); + first_time = 0; + arc4random_stir(); + } + + RC4(&rc4, sizeof(r), (unsigned char *)&r, (unsigned char *)&r); + + rc4_ready -= sizeof(r); + + return(r); +} + +void arc4random_stir(void) +{ + unsigned char rand_buf[SEED_SIZE]; + + memset(&rc4, 0, sizeof(rc4)); + if (!RAND_bytes(rand_buf, sizeof(rand_buf))) + fatal("Couldn't obtain random bytes (error %ld)", + ERR_get_error()); + RC4_set_key(&rc4, sizeof(rand_buf), rand_buf); + memset(rand_buf, 0, sizeof(rand_buf)); + + rc4_ready = REKEY_BYTES; +} +#endif /* !HAVE_ARC4RANDOM */ |