OpenSolaris_b135/lib/crypt_modules/sha256/crypt_sha.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Portions of this code from crypt_bsdmd5.so (bsdmd5.c) :
* ----------------------------------------------------------------------------
* "THE BEER-WARE LICENSE" (Revision 42):
* <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
* ----------------------------------------------------------------------------
*
* $FreeBSD: crypt.c,v 1.5 1996/10/14 08:34:02 phk Exp $
*
*/
/*
* Implements the specification from:
*
* From http://people.redhat.com/drepper/SHA-crypt.txt
*
* Portions of the code taken from inspired by or verified against the
* source in the above document which is licensed as:
*
* "Released into the Public Domain by Ulrich Drepper <drepper@redhat.com>."
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <alloca.h>
#include <sha2.h>
#include <crypt.h>
#define MAX_SALT_LEN 16
#define ROUNDS_DEFAULT 5000
#define ROUNDS_MIN 1000
#define ROUNDS_MAX 999999999
#ifdef CRYPT_SHA256
#define DIGEST_CTX SHA256_CTX
#define DIGESTInit SHA256Init
#define DIGESTUpdate SHA256Update
#define DIGESTFinal SHA256Final
#define DIGEST_LEN SHA256_DIGEST_LENGTH
#define MIXCHARS 32
static const char crypt_alg_magic[] = "$5";
#elif CRYPT_SHA512
#define DIGEST_CTX SHA512_CTX
#define DIGESTInit SHA512Init
#define DIGESTUpdate SHA512Update
#define DIGESTFinal SHA512Final
#define DIGEST_LEN SHA512_DIGEST_LENGTH
#define MIXCHARS 64
static const char crypt_alg_magic[] = "$6";
#else
#error "One of CRYPT_256 or CRYPT_512 must be defined"
#endif
static const int crypt_alg_magic_len = sizeof (crypt_alg_magic) - 1;
static uchar_t b64t[] = /* 0 ... 63 => ascii - 64 */
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
#define b64_from_24bit(B2, B1, B0, N) \
{ \
uint_t w = ((B2) << 16) | ((B1) << 8) | (B0); \
int n = (N); \
while (--n >= 0 && ctbufflen > 0) { \
*p++ = b64t[w & 0x3f]; \
w >>= 6; \
ctbufflen--; \
} \
}
static void
to64(char *s, uint64_t v, int n)
{
while (--n >= 0) {
*s++ = b64t[v & 0x3f];
v >>= 6;
}
}
#define ROUNDS "rounds="
#define ROUNDSLEN (sizeof (ROUNDS) - 1)
/*
* get the integer value after rounds= where ever it occurs in the string.
* if the last char after the int is a , or $ that is fine anything else is an
* error.
*/
static uint32_t
getrounds(const char *s)
{
char *r, *p, *e;
long val;
if (s == NULL)
return (0);
if ((r = strstr(s, ROUNDS)) == NULL) {
return (0);
}
if (strncmp(r, ROUNDS, ROUNDSLEN) != 0) {
return (0);
}
p = r + ROUNDSLEN;
errno = 0;
val = strtol(p, &e, 10);
/*
* An error occurred or there is non-numeric stuff at the end
* which isn't one of the crypt(3c) special chars ',' or '$'
*/
if (errno != 0 || val < 0 ||
!(*e == '\0' || *e == ',' || *e == '$')) {
return (0);
}
return ((uint32_t)val);
}
/* ARGSUSED4 */
char *
crypt_genhash_impl(char *ctbuffer,
size_t ctbufflen,
const char *plaintext,
const char *switchsalt,
const char **params)
{
int salt_len, plaintext_len, i;
char *salt;
uchar_t A[DIGEST_LEN];
uchar_t B[DIGEST_LEN];
uchar_t DP[DIGEST_LEN];
uchar_t DS[DIGEST_LEN];
DIGEST_CTX ctxA, ctxB, ctxC, ctxDP, ctxDS;
int rounds = ROUNDS_DEFAULT;
int srounds = 0;
boolean_t custom_rounds = B_FALSE;
char *p;
char *P, *Pp;
char *S, *Sp;
/* Refine the salt */
salt = (char *)switchsalt;
/* skip our magic string */
if (strncmp((char *)salt, crypt_alg_magic, crypt_alg_magic_len) == 0) {
salt += crypt_alg_magic_len + 1;
}
srounds = getrounds(salt);
if (srounds != 0) {
rounds = MAX(ROUNDS_MIN, MIN(srounds, ROUNDS_MAX));
custom_rounds = B_TRUE;
p = strchr(salt, '$');
if (p != NULL)
salt = p + 1;
}
salt_len = MIN(strcspn(salt, "$"), MAX_SALT_LEN);
plaintext_len = strlen(plaintext);
/* 1. */
DIGESTInit(&ctxA);
/* 2. The password first, since that is what is most unknown */
DIGESTUpdate(&ctxA, plaintext, plaintext_len);
/* 3. Then the raw salt */
DIGESTUpdate(&ctxA, salt, salt_len);
/* 4. - 8. */
DIGESTInit(&ctxB);
DIGESTUpdate(&ctxB, plaintext, plaintext_len);
DIGESTUpdate(&ctxB, salt, salt_len);
DIGESTUpdate(&ctxB, plaintext, plaintext_len);
DIGESTFinal(B, &ctxB);
/* 9. - 10. */
for (i = plaintext_len; i > MIXCHARS; i -= MIXCHARS)
DIGESTUpdate(&ctxA, B, MIXCHARS);
DIGESTUpdate(&ctxA, B, i);
/* 11. */
for (i = plaintext_len; i > 0; i >>= 1) {
if ((i & 1) != 0) {
DIGESTUpdate(&ctxA, B, MIXCHARS);
} else {
DIGESTUpdate(&ctxA, plaintext, plaintext_len);
}
}
/* 12. */
DIGESTFinal(A, &ctxA);
/* 13. - 15. */
DIGESTInit(&ctxDP);
for (i = 0; i < plaintext_len; i++)
DIGESTUpdate(&ctxDP, plaintext, plaintext_len);
DIGESTFinal(DP, &ctxDP);
/* 16. */
Pp = P = alloca(plaintext_len);
for (i = plaintext_len; i >= MIXCHARS; i -= MIXCHARS) {
Pp = (char *)(memcpy(Pp, DP, MIXCHARS)) + MIXCHARS;
}
(void) memcpy(Pp, DP, i);
/* 17. - 19. */
DIGESTInit(&ctxDS);
for (i = 0; i < 16 + (uint8_t)A[0]; i++)
DIGESTUpdate(&ctxDS, salt, salt_len);
DIGESTFinal(DS, &ctxDS);
/* 20. */
Sp = S = alloca(salt_len);
for (i = salt_len; i >= MIXCHARS; i -= MIXCHARS) {
Sp = (char *)(memcpy(Sp, DS, MIXCHARS)) + MIXCHARS;
}
(void) memcpy(Sp, DS, i);
/* 21. */
for (i = 0; i < rounds; i++) {
DIGESTInit(&ctxC);
if ((i & 1) != 0) {
DIGESTUpdate(&ctxC, P, plaintext_len);
} else {
if (i == 0)
DIGESTUpdate(&ctxC, A, MIXCHARS);
else
DIGESTUpdate(&ctxC, DP, MIXCHARS);
}
if (i % 3 != 0) {
DIGESTUpdate(&ctxC, S, salt_len);
}
if (i % 7 != 0) {
DIGESTUpdate(&ctxC, P, plaintext_len);
}
if ((i & 1) != 0) {
if (i == 0)
DIGESTUpdate(&ctxC, A, MIXCHARS);
else
DIGESTUpdate(&ctxC, DP, MIXCHARS);
} else {
DIGESTUpdate(&ctxC, P, plaintext_len);
}
DIGESTFinal(DP, &ctxC);
}
/* 22. Now make the output string */
if (custom_rounds) {
(void) snprintf(ctbuffer, ctbufflen,
"%s$rounds=%zu$", crypt_alg_magic, rounds);
} else {
(void) snprintf(ctbuffer, ctbufflen,
"%s$", crypt_alg_magic);
}
(void) strncat(ctbuffer, (const char *)salt, salt_len);
(void) strlcat(ctbuffer, "$", ctbufflen);
p = ctbuffer + strlen(ctbuffer);
ctbufflen -= strlen(ctbuffer);
#ifdef CRYPT_SHA256
b64_from_24bit(DP[ 0], DP[10], DP[20], 4);
b64_from_24bit(DP[21], DP[ 1], DP[11], 4);
b64_from_24bit(DP[12], DP[22], DP[ 2], 4);
b64_from_24bit(DP[ 3], DP[13], DP[23], 4);
b64_from_24bit(DP[24], DP[ 4], DP[14], 4);
b64_from_24bit(DP[15], DP[25], DP[ 5], 4);
b64_from_24bit(DP[ 6], DP[16], DP[26], 4);
b64_from_24bit(DP[27], DP[ 7], DP[17], 4);
b64_from_24bit(DP[18], DP[28], DP[ 8], 4);
b64_from_24bit(DP[ 9], DP[19], DP[29], 4);
b64_from_24bit(0, DP[31], DP[30], 3);
#elif CRYPT_SHA512
b64_from_24bit(DP[ 0], DP[21], DP[42], 4);
b64_from_24bit(DP[22], DP[43], DP[ 1], 4);
b64_from_24bit(DP[44], DP[ 2], DP[23], 4);
b64_from_24bit(DP[ 3], DP[24], DP[45], 4);
b64_from_24bit(DP[25], DP[46], DP[ 4], 4);
b64_from_24bit(DP[47], DP[ 5], DP[26], 4);
b64_from_24bit(DP[ 6], DP[27], DP[48], 4);
b64_from_24bit(DP[28], DP[49], DP[ 7], 4);
b64_from_24bit(DP[50], DP[ 8], DP[29], 4);
b64_from_24bit(DP[ 9], DP[30], DP[51], 4);
b64_from_24bit(DP[31], DP[52], DP[10], 4);
b64_from_24bit(DP[53], DP[11], DP[32], 4);
b64_from_24bit(DP[12], DP[33], DP[54], 4);
b64_from_24bit(DP[34], DP[55], DP[13], 4);
b64_from_24bit(DP[56], DP[14], DP[35], 4);
b64_from_24bit(DP[15], DP[36], DP[57], 4);
b64_from_24bit(DP[37], DP[58], DP[16], 4);
b64_from_24bit(DP[59], DP[17], DP[38], 4);
b64_from_24bit(DP[18], DP[39], DP[60], 4);
b64_from_24bit(DP[40], DP[61], DP[19], 4);
b64_from_24bit(DP[62], DP[20], DP[41], 4);
b64_from_24bit(0, 0, DP[63], 2);
#endif
*p = '\0';
(void) memset(A, 0, sizeof (A));
(void) memset(B, 0, sizeof (B));
(void) memset(DP, 0, sizeof (DP));
(void) memset(DS, 0, sizeof (DS));
return (ctbuffer);
}
/* ARGSUSED3 */
char *
crypt_gensalt_impl(char *gsbuffer,
size_t gsbufflen,
const char *oldsalt,
const struct passwd *userinfo,
const char **params)
{
int fd;
int err;
ssize_t got;
uint64_t rndval;
uint32_t confrounds = 0;
uint32_t saltrounds;
char rndstr[sizeof (rndval) + 1];
int i;
for (i = 0; params != NULL && params[i] != NULL; i++) {
if (strncmp(params[i], ROUNDS, ROUNDSLEN) == 0) {
confrounds = getrounds(params[i]);
} else {
errno = EINVAL;
return (NULL);
}
}
/*
* If the config file has a higher value for rounds= than what
* was in the old salt use that, otherwise keep what was in the
* old salt.
*/
saltrounds = getrounds(oldsalt);
if (confrounds > saltrounds) {
saltrounds = confrounds;
}
if ((fd = open("/dev/urandom", O_RDONLY)) == -1) {
return (NULL);
}
got = read(fd, &rndval, sizeof (rndval));
if (got < sizeof (rndval)) {
err = errno;
(void) close(fd);
errno = err;
return (NULL);
}
(void) close(fd);
to64((char *)&rndstr, rndval, sizeof (rndval));
rndstr[sizeof (rndstr) - 1] = 0;
if (saltrounds > 0) {
if (snprintf(gsbuffer, gsbufflen,
"%s$rounds=%d$",
crypt_alg_magic, saltrounds) >= gsbufflen)
goto fail;
} else {
if (snprintf(gsbuffer, gsbufflen,
"%s$", crypt_alg_magic) >= gsbufflen)
goto fail;
}
if (strlcat(gsbuffer, rndstr, gsbufflen) >= gsbufflen)
goto fail;
if (strlcat(gsbuffer, "$", gsbufflen) >= gsbufflen)
goto fail;
return (gsbuffer);
fail:
(void) memset(gsbuffer, 0, gsbufflen);
return (gsbuffer);
}