diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/libutil/Makefile | 8 | ||||
| -rw-r--r-- | lib/libutil/bcrypt_pbkdf.3 | 68 | ||||
| -rw-r--r-- | lib/libutil/bcrypt_pbkdf.c | 163 | ||||
| -rw-r--r-- | lib/libutil/pkcs5_pbkdf2.3 | 7 | ||||
| -rw-r--r-- | lib/libutil/pkcs5_pbkdf2.c | 10 | ||||
| -rw-r--r-- | lib/libutil/shlib_version | 2 | ||||
| -rw-r--r-- | lib/libutil/util.h | 8 |
7 files changed, 251 insertions, 15 deletions
diff --git a/lib/libutil/Makefile b/lib/libutil/Makefile index 080671083f7..d4e748231ba 100644 --- a/lib/libutil/Makefile +++ b/lib/libutil/Makefile @@ -1,15 +1,17 @@ -# $OpenBSD: Makefile,v 1.35 2012/09/06 19:41:59 tedu Exp $ +# $OpenBSD: Makefile,v 1.36 2013/06/03 21:07:02 tedu Exp $ # $NetBSD: Makefile,v 1.8 1996/05/16 07:03:28 thorpej Exp $ LIB= util HDRS= util.h imsg.h -SRCS= check_expire.c duid.c getmaxpartitions.c getrawpartition.c login.c \ +SRCS= bcrypt_pbkdf.c check_expire.c duid.c getmaxpartitions.c \ + getrawpartition.c login.c \ login_tty.c logout.c logwtmp.c opendev.c passwd.c pty.c readlabel.c \ login_fbtab.c uucplock.c fparseln.c opendisk.c pidfile.c \ fmt_scaled.c imsg.c imsg-buffer.c pkcs5_pbkdf2.c -MAN= check_expire.3 getmaxpartitions.3 getrawpartition.3 isduid.3 login.3 \ +MAN= bcrypt_pbkdf.3 check_expire.3 getmaxpartitions.3 getrawpartition.3 \ + isduid.3 login.3 \ opendev.3 openpty.3 pw_init.3 pw_lock.3 readlabelfs.3 uucplock.3 \ fparseln.3 opendisk.3 login_fbtab.3 pidfile.3 fmt_scaled.3 imsg_init.3 \ pkcs5_pbkdf2.3 diff --git a/lib/libutil/bcrypt_pbkdf.3 b/lib/libutil/bcrypt_pbkdf.3 new file mode 100644 index 00000000000..65bec948ee8 --- /dev/null +++ b/lib/libutil/bcrypt_pbkdf.3 @@ -0,0 +1,68 @@ +.\" $OpenBSD: bcrypt_pbkdf.3,v 1.1 2013/06/03 21:07:02 tedu Exp $ +.\" +.\" Copyright (c) 2012 Ted Unangst <tedu@openbsd.org> +.\" +.\" Permission to use, copy, modify, and distribute this software for any +.\" purpose with or without fee is hereby granted, provided that the above +.\" copyright notice and this permission notice appear in all copies. +.\" +.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +.\" +.Dd $Mdocdate: June 3 2013 $ +.Dt BCRYPT_PBKDF 3 +.Os +.Sh NAME +.Nm bcrypt_pbkdf +.Nd bcrypt password-based key derivation function +.Sh SYNOPSIS +.Fd #include <util.h> +.Ft int +.Fn bcrypt_pbkdf "const char *pass" "size_t pass_len" "const uint8_t *salt" \ + "size_t salt_len" "uint8_t *key" "size_t key_len" "unsigned int rounds" +.Sh DESCRIPTION +The +.Nm +function converts a password into a byte array suitable for use as +an encryption key. +The password and salt values are combined and repeatedly hashed +.Ar rounds +times. +The salt value should be randomly generated beforehand. +The repeated hashing is designed to thwart discovery of the key via +password guessing attacks. +The higher the number of rounds, the slower each attempt will be. +.\" A minimum value of at least 1000 is recommended. +.Sh RETURN VALUES +The +.Fn bcrypt_pbkdf +function returns 0 to indicate success and -1 for failure. +.\" .Sh EXAMPLES +.\" .Sh ERRORS +.Sh SEE ALSO +.Xr sha1 1 , +.Xr bcrypt 3 +.Sh STANDARDS +.Rs +.%A Niels Provos and David Mazieres +.%D June 1999 +.%T A Future-Adaptable Password Scheme +.Re +.Pp +.Rs +.%A B. Kaliski +.%D September 2000 +.%R RFC 2898 +.%T PKCS #5: Password-Based Cryptography Specification Version 2.0 +.Re +.\" .Sh HISTORY +.\" .Sh AUTHORS +.Sh CAVEATS +This implementation deviates slightly from the PBKDF2 standard by mixing +output key bits nonlinearly. +.\" .Sh BUGS diff --git a/lib/libutil/bcrypt_pbkdf.c b/lib/libutil/bcrypt_pbkdf.c new file mode 100644 index 00000000000..732499be0c9 --- /dev/null +++ b/lib/libutil/bcrypt_pbkdf.c @@ -0,0 +1,163 @@ +/* $OpenBSD: bcrypt_pbkdf.c,v 1.1 2013/06/03 21:07:02 tedu Exp $ */ +/* + * Copyright (c) 2013 Ted Unangst <tedu@openbsd.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/types.h> +#include <sys/param.h> + +#include <stdlib.h> +#include <blf.h> +#include <sha2.h> +#include <string.h> +#include <util.h> + +/* + * pkcs #5 pbkdf2 implementation using the "bcrypt" hash + * + * The bcrypt hash function is derived from the bcrypt password hashing + * function with the following modifications: + * 1. The input password and salt are preprocessed with SHA512. + * 2. The output length is expanded to 256 bits. + * 3. Subsequently the magic string to be encrypted is lengthened and modifed + * to "OxychromaticBlowfishSwatDynamite" + * 4. The hash function is defined to perform 64 rounds of initial state + * expansion. (More rounds are performed by iterating the hash.) + * + * Note that this implementation pulls the SHA512 operations into the caller + * as a performance optimization. + * + * One modification from official pbkdf2. Instead of outputting key material + * linearly, we mix it. pbkdf2 has a known weakness where if one uses it to + * generate (i.e.) 512 bits of key material for use as two 256 bit keys, an + * attacker can merely run once through the outer loop below, but the user + * always runs it twice. Shuffling output bytes requires computing the + * entirety of the key material to assemble any subkey. This is something a + * wise caller could do; we just do it for you. + */ + +#define BCRYPT_BLOCKS 8 +#define BCRYPT_HASHSIZE (BCRYPT_BLOCKS * 4) + +static void +bcrypt_hash(uint8_t sha2pass[SHA512_DIGEST_LENGTH], + uint8_t sha2salt[SHA512_DIGEST_LENGTH], uint8_t out[BCRYPT_HASHSIZE]) +{ + blf_ctx state; + uint8_t ciphertext[BCRYPT_HASHSIZE] = + "OxychromaticBlowfishSwatDynamite"; + uint32_t cdata[BCRYPT_BLOCKS]; + int i; + uint16_t j; + + /* key expansion */ + Blowfish_initstate(&state); + Blowfish_expandstate(&state, sha2salt, sizeof(sha2salt), sha2pass, + sizeof(sha2pass)); + for (i = 0; i < 64; i++) { + Blowfish_expand0state(&state, sha2salt, sizeof(sha2salt)); + Blowfish_expand0state(&state, sha2pass, sizeof(sha2pass)); + } + + /* encryption */ + j = 0; + for (i = 0; i < BCRYPT_BLOCKS; i++) + cdata[i] = Blowfish_stream2word(ciphertext, sizeof(ciphertext), + &j); + for (i = 0; i < 64; i++) + blf_enc(&state, cdata, sizeof(cdata) / sizeof(uint64_t)); + + /* copy out */ + for (i = 0; i < BCRYPT_BLOCKS; i++) { + out[4 * i + 3] = (cdata[i] >> 24) & 0xff; + out[4 * i + 2] = (cdata[i] >> 16) & 0xff; + out[4 * i + 1] = (cdata[i] >> 8) & 0xff; + out[4 * i + 0] = cdata[i] & 0xff; + } + + /* zap */ + memset(ciphertext, 0, sizeof(ciphertext)); + memset(cdata, 0, sizeof(cdata)); + memset(&state, 0, sizeof(state)); +} + +int +bcrypt_pbkdf(const char *pass, size_t passlen, const uint8_t *salt, size_t saltlen, + uint8_t *key, size_t keylen, unsigned int rounds) +{ + SHA2_CTX ctx; + uint8_t sha2pass[SHA512_DIGEST_LENGTH]; + uint8_t sha2salt[SHA512_DIGEST_LENGTH]; + uint8_t out[BCRYPT_HASHSIZE]; + uint8_t tmpout[BCRYPT_HASHSIZE]; + uint8_t countsalt[4]; + size_t i, j, amt, stride; + uint32_t count; + + /* nothing crazy */ + if (rounds < 1) + return -1; + if (passlen == 0 || saltlen == 0 || keylen == 0 || + keylen > sizeof(out) * sizeof(out)) + return -1; + stride = (keylen + sizeof(out) - 1) / sizeof(out); + amt = (keylen + stride - 1) / stride; + + /* collapse password */ + SHA512Init(&ctx); + SHA512Update(&ctx, pass, passlen); + SHA512Final(sha2pass, &ctx); + + + /* generate key, sizeof(out) at a time */ + for (count = 1; keylen > 0; count++) { + countsalt[0] = (count >> 24) & 0xff; + countsalt[1] = (count >> 16) & 0xff; + countsalt[2] = (count >> 8) & 0xff; + countsalt[3] = count & 0xff; + + /* first round, salt is salt */ + SHA512Init(&ctx); + SHA512Update(&ctx, salt, saltlen); + SHA512Update(&ctx, countsalt, sizeof(countsalt)); + SHA512Final(sha2salt, &ctx); + bcrypt_hash(sha2pass, sha2salt, tmpout); + memcpy(out, tmpout, sizeof(out)); + + for (i = 1; i < rounds; i++) { + /* subsequent rounds, salt is previous output */ + SHA512Init(&ctx); + SHA512Update(&ctx, tmpout, sizeof(tmpout)); + SHA512Final(sha2salt, &ctx); + bcrypt_hash(sha2pass, sha2salt, tmpout); + for (j = 0; j < sizeof(out); j++) + out[j] ^= tmpout[j]; + } + + /* + * pbkdf2 deviation: ouput the key material non-linearly. + */ + amt = MIN(amt, keylen); + for (i = 0; i < amt; i++) + key[i * stride + (count - 1)] = out[i]; + keylen -= amt; + } + + /* zap */ + memset(&ctx, 0, sizeof(ctx)); + memset(out, 0, sizeof(out)); + + return 0; +} diff --git a/lib/libutil/pkcs5_pbkdf2.3 b/lib/libutil/pkcs5_pbkdf2.3 index 3a924e75b15..803e484cf71 100644 --- a/lib/libutil/pkcs5_pbkdf2.3 +++ b/lib/libutil/pkcs5_pbkdf2.3 @@ -1,4 +1,4 @@ -.\" $OpenBSD: pkcs5_pbkdf2.3,v 1.3 2012/09/07 05:48:20 jmc Exp $ +.\" $OpenBSD: pkcs5_pbkdf2.3,v 1.4 2013/06/03 21:07:02 tedu Exp $ .\" .\" Copyright (c) 2012 Ted Unangst <tedu@openbsd.org> .\" @@ -14,7 +14,7 @@ .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. .\" -.Dd $Mdocdate: September 7 2012 $ +.Dd $Mdocdate: June 3 2013 $ .Dt PKCS5_PBKDF2 3 .Os .Sh NAME @@ -45,7 +45,8 @@ function returns 0 to indicate success and -1 for failure. .\" .Sh EXAMPLES .\" .Sh ERRORS .Sh SEE ALSO -.Xr sha1 1 +.Xr sha1 1 , +.Xr bcrypt_pbkdf 3 .Sh STANDARDS .Rs .%A B. Kaliski diff --git a/lib/libutil/pkcs5_pbkdf2.c b/lib/libutil/pkcs5_pbkdf2.c index 17e54c3dc55..26c2b6466fe 100644 --- a/lib/libutil/pkcs5_pbkdf2.c +++ b/lib/libutil/pkcs5_pbkdf2.c @@ -1,4 +1,4 @@ -/* $OpenBSD: pkcs5_pbkdf2.c,v 1.3 2012/09/09 18:08:21 matthew Exp $ */ +/* $OpenBSD: pkcs5_pbkdf2.c,v 1.4 2013/06/03 21:07:02 tedu Exp $ */ /*- * Copyright (c) 2008 Damien Bergamini <damien.bergamini@free.fr> @@ -73,11 +73,11 @@ hmac_sha1(const u_int8_t *text, size_t text_len, const u_int8_t *key, * Code based on IEEE Std 802.11-2007, Annex H.4.2. */ int -pkcs5_pbkdf2(const char *pass, size_t pass_len, const char *salt, size_t salt_len, - u_int8_t *key, size_t key_len, unsigned int rounds) +pkcs5_pbkdf2(const char *pass, size_t pass_len, const uint8_t *salt, size_t salt_len, + uint8_t *key, size_t key_len, unsigned int rounds) { - u_int8_t *asalt, obuf[SHA1_DIGEST_LENGTH]; - u_int8_t d1[SHA1_DIGEST_LENGTH], d2[SHA1_DIGEST_LENGTH]; + uint8_t *asalt, obuf[SHA1_DIGEST_LENGTH]; + uint8_t d1[SHA1_DIGEST_LENGTH], d2[SHA1_DIGEST_LENGTH]; unsigned int i, j; unsigned int count; size_t r; diff --git a/lib/libutil/shlib_version b/lib/libutil/shlib_version index f6b149e5862..18279d15316 100644 --- a/lib/libutil/shlib_version +++ b/lib/libutil/shlib_version @@ -1,2 +1,2 @@ major=11 -minor=4 +minor=5 diff --git a/lib/libutil/util.h b/lib/libutil/util.h index 92e3c45ed20..469e003d587 100644 --- a/lib/libutil/util.h +++ b/lib/libutil/util.h @@ -1,4 +1,4 @@ -/* $OpenBSD: util.h,v 1.33 2012/12/05 23:20:06 deraadt Exp $ */ +/* $OpenBSD: util.h,v 1.34 2013/06/03 21:07:02 tedu Exp $ */ /* $NetBSD: util.h,v 1.2 1996/05/16 07:00:22 thorpej Exp $ */ /*- @@ -113,8 +113,10 @@ int uu_unlock(const char *); int fmt_scaled(long long, char *); int scan_scaled(char *, long long *); int isduid(const char *, int); -int pkcs5_pbkdf2(const char *, size_t, const char *, size_t, - u_int8_t *, size_t, unsigned int); +int pkcs5_pbkdf2(const char *, size_t, const uint8_t *, size_t, + uint8_t *, size_t, unsigned int); +int bcrypt_pbkdf(const char *, size_t, const uint8_t *, size_t, + uint8_t *, size_t, unsigned int); __END_DECLS |