freebsd-skq/sys/geom/eli/pkcs5v2.c
allanjude 19cde117cf Make additional parts of sys/geom/eli more usable in userspace
The upcoming GELI support in the loader reuses parts of this code
Some ifdefs are added, and some code is moved outside of existing ifdefs

The HMAC parts of GELI are broken out into their own file, to separate
them from the kernel crypto/openssl dependant parts that are replaced
in the boot code.

Passed the GELI regression suite (tools/regression/geom/eli)
 Files=20 Tests=14996
 Result: PASS

Reviewed by:	pjd, delphij
MFC after:	1 week
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D4699
2016-01-07 05:47:34 +00:00

126 lines
3.5 KiB
C

/*-
* Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* 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 AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#ifdef _KERNEL
#include <sys/systm.h>
#include <sys/kernel.h>
#else
#include <sys/resource.h>
#include <stdint.h>
#include <strings.h>
#endif
#include <geom/eli/g_eli.h>
#include <geom/eli/pkcs5v2.h>
static __inline void
xor(uint8_t *dst, const uint8_t *src, size_t size)
{
for (; size > 0; size--)
*dst++ ^= *src++;
}
void
pkcs5v2_genkey(uint8_t *key, unsigned keylen, const uint8_t *salt,
size_t saltsize, const char *passphrase, u_int iterations)
{
uint8_t md[SHA512_MDLEN], saltcount[saltsize + sizeof(uint32_t)];
uint8_t *counter, *keyp;
u_int i, bsize, passlen;
uint32_t count;
passlen = strlen(passphrase);
bzero(key, keylen);
bcopy(salt, saltcount, saltsize);
counter = saltcount + saltsize;
keyp = key;
for (count = 1; keylen > 0; count++, keylen -= bsize, keyp += bsize) {
bsize = MIN(keylen, sizeof(md));
counter[0] = (count >> 24) & 0xff;
counter[1] = (count >> 16) & 0xff;
counter[2] = (count >> 8) & 0xff;
counter[3] = count & 0xff;
g_eli_crypto_hmac(passphrase, passlen, saltcount,
sizeof(saltcount), md, 0);
xor(keyp, md, bsize);
for(i = 1; i < iterations; i++) {
g_eli_crypto_hmac(passphrase, passlen, md, sizeof(md),
md, 0);
xor(keyp, md, bsize);
}
}
}
#ifndef _KERNEL
#ifndef _STAND
/*
* Return the number of microseconds needed for 'interations' iterations.
*/
static int
pkcs5v2_probe(int iterations)
{
uint8_t key[G_ELI_USERKEYLEN], salt[G_ELI_SALTLEN];
uint8_t passphrase[] = "passphrase";
struct rusage start, end;
int usecs;
getrusage(RUSAGE_SELF, &start);
pkcs5v2_genkey(key, sizeof(key), salt, sizeof(salt), passphrase,
iterations);
getrusage(RUSAGE_SELF, &end);
usecs = end.ru_utime.tv_sec - start.ru_utime.tv_sec;
usecs *= 1000000;
usecs += end.ru_utime.tv_usec - start.ru_utime.tv_usec;
return (usecs);
}
/*
* Return the number of iterations which takes 'usecs' microseconds.
*/
int
pkcs5v2_calculate(int usecs)
{
int iterations, v;
for (iterations = 1; ; iterations <<= 1) {
v = pkcs5v2_probe(iterations);
if (v > 2000000)
break;
}
return (((intmax_t)iterations * (intmax_t)usecs) / v);
}
#endif /* !_STAND */
#endif /* !_KERNEL */