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author | djm <devnull@localhost> | 2006-05-22 11:53:27 +0000 |
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committer | djm <devnull@localhost> | 2006-05-22 11:53:27 +0000 |
commit | 08f7132af5c94eaababc9811afb2a90c9c9e2bf8 (patch) | |
tree | 7e189b2014644405e53c41df254a4f3740091ad1 /bcrypt/bcrypt.c | |
download | py-bcrypt-08f7132af5c94eaababc9811afb2a90c9c9e2bf8.tar.gz |
Initial revision
Diffstat (limited to 'bcrypt/bcrypt.c')
-rw-r--r-- | bcrypt/bcrypt.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/bcrypt/bcrypt.c b/bcrypt/bcrypt.c new file mode 100644 index 0000000..5f12013 --- /dev/null +++ b/bcrypt/bcrypt.c @@ -0,0 +1,279 @@ +/* $OpenBSD: bcrypt.c,v 1.20 2006/04/03 19:55:49 deraadt Exp $ */ + +/* + * Copyright 1997 Niels Provos <provos@physnet.uni-hamburg.de> + * 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by Niels Provos. + * 4. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * 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. + */ + +/* This password hashing algorithm was designed by David Mazieres + * <dm@lcs.mit.edu> and works as follows: + * + * 1. state := InitState () + * 2. state := ExpandKey (state, salt, password) 3. + * REPEAT rounds: + * state := ExpandKey (state, 0, salt) + * state := ExpandKey(state, 0, password) + * 4. ctext := "OrpheanBeholderScryDoubt" + * 5. REPEAT 64: + * ctext := Encrypt_ECB (state, ctext); + * 6. RETURN Concatenate (salt, ctext); + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <sys/types.h> +#include <string.h> +#include "pybc_blf.h" + +/* This implementation is adaptable to current computing power. + * You can have up to 2^31 rounds which should be enough for some + * time to come. + */ + +#define BCRYPT_VERSION '2' +#define BCRYPT_MAXSALT 16 /* Precomputation is just so nice */ +#define BCRYPT_BLOCKS 6 /* Ciphertext blocks */ +#define BCRYPT_MINROUNDS 16 /* we have log2(rounds) in salt */ + +char *pybc_bcrypt(const char *, const char *); +void encode_salt(char *, u_int8_t *, u_int16_t, u_int8_t); + +static void encode_base64(u_int8_t *, u_int8_t *, u_int16_t); +static void decode_base64(u_int8_t *, u_int16_t, u_int8_t *); + +static char encrypted[128]; +static char error[] = ":"; + +const static u_int8_t Base64Code[] = +"./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"; + +const static u_int8_t index_64[128] = { + 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, + 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, + 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, + 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, + 255, 255, 255, 255, 255, 255, 0, 1, 54, 55, + 56, 57, 58, 59, 60, 61, 62, 63, 255, 255, + 255, 255, 255, 255, 255, 2, 3, 4, 5, 6, + 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, + 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, + 255, 255, 255, 255, 255, 255, 28, 29, 30, + 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, + 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, + 51, 52, 53, 255, 255, 255, 255, 255 +}; +#define CHAR64(c) ( (c) > 127 ? 255 : index_64[(c)]) + +static void +decode_base64(u_int8_t *buffer, u_int16_t len, u_int8_t *data) +{ + u_int8_t *bp = buffer; + u_int8_t *p = data; + u_int8_t c1, c2, c3, c4; + while (bp < buffer + len) { + c1 = CHAR64(*p); + c2 = CHAR64(*(p + 1)); + + /* Invalid data */ + if (c1 == 255 || c2 == 255) + break; + + *bp++ = (c1 << 2) | ((c2 & 0x30) >> 4); + if (bp >= buffer + len) + break; + + c3 = CHAR64(*(p + 2)); + if (c3 == 255) + break; + + *bp++ = ((c2 & 0x0f) << 4) | ((c3 & 0x3c) >> 2); + if (bp >= buffer + len) + break; + + c4 = CHAR64(*(p + 3)); + if (c4 == 255) + break; + *bp++ = ((c3 & 0x03) << 6) | c4; + + p += 4; + } +} + +void +encode_salt(char *salt, u_int8_t *csalt, u_int16_t clen, u_int8_t logr) +{ + salt[0] = '$'; + salt[1] = BCRYPT_VERSION; + salt[2] = 'a'; + salt[3] = '$'; + + snprintf(salt + 4, 4, "%2.2u$", logr); + + encode_base64((u_int8_t *) salt + 7, csalt, clen); +} + +/* We handle $Vers$log2(NumRounds)$salt+passwd$ + i.e. $2$04$iwouldntknowwhattosayetKdJ6iFtacBqJdKe6aW7ou */ + +char * +pybc_bcrypt(const char *key, const char *salt) +{ + pybc_blf_ctx state; + u_int32_t rounds, i, k; + u_int16_t j; + u_int8_t key_len, salt_len, logr, minor; + u_int8_t ciphertext[4 * BCRYPT_BLOCKS] = "OrpheanBeholderScryDoubt"; + u_int8_t csalt[BCRYPT_MAXSALT]; + u_int32_t cdata[BCRYPT_BLOCKS]; + int n; + + /* Discard "$" identifier */ + salt++; + + if (*salt > BCRYPT_VERSION) { + /* How do I handle errors ? Return ':' */ + return error; + } + + /* Check for minor versions */ + if (salt[1] != '$') { + switch (salt[1]) { + case 'a': + /* 'ab' should not yield the same as 'abab' */ + minor = salt[1]; + salt++; + break; + default: + return error; + } + } else + minor = 0; + + /* Discard version + "$" identifier */ + salt += 2; + + if (salt[2] != '$') + /* Out of sync with passwd entry */ + return error; + + /* Computer power doesn't increase linear, 2^x should be fine */ + n = atoi(salt); + if (n > 31 || n < 0) + return error; + logr = (u_int8_t)n; + if ((rounds = (u_int32_t) 1 << logr) < BCRYPT_MINROUNDS) + return error; + + /* Discard num rounds + "$" identifier */ + salt += 3; + + if (strlen(salt) * 3 / 4 < BCRYPT_MAXSALT) + return error; + + /* We dont want the base64 salt but the raw data */ + decode_base64(csalt, BCRYPT_MAXSALT, (u_int8_t *) salt); + salt_len = BCRYPT_MAXSALT; + key_len = strlen(key) + (minor >= 'a' ? 1 : 0); + + /* Setting up S-Boxes and Subkeys */ + pybc_Blowfish_initstate(&state); + pybc_Blowfish_expandstate(&state, csalt, salt_len, + (u_int8_t *) key, key_len); + for (k = 0; k < rounds; k++) { + pybc_Blowfish_expand0state(&state, (u_int8_t *) key, key_len); + pybc_Blowfish_expand0state(&state, csalt, salt_len); + } + + /* This can be precomputed later */ + j = 0; + for (i = 0; i < BCRYPT_BLOCKS; i++) { + cdata[i] = pybc_Blowfish_stream2word(ciphertext, + 4 * BCRYPT_BLOCKS, &j); + } + + /* Now do the encryption */ + for (k = 0; k < 64; k++) + pybc_blf_enc(&state, cdata, BCRYPT_BLOCKS / 2); + + for (i = 0; i < BCRYPT_BLOCKS; i++) { + ciphertext[4 * i + 3] = cdata[i] & 0xff; + cdata[i] = cdata[i] >> 8; + ciphertext[4 * i + 2] = cdata[i] & 0xff; + cdata[i] = cdata[i] >> 8; + ciphertext[4 * i + 1] = cdata[i] & 0xff; + cdata[i] = cdata[i] >> 8; + ciphertext[4 * i + 0] = cdata[i] & 0xff; + } + + + i = 0; + encrypted[i++] = '$'; + encrypted[i++] = BCRYPT_VERSION; + if (minor) + encrypted[i++] = minor; + encrypted[i++] = '$'; + + snprintf(encrypted + i, 4, "%2.2u$", logr); + + encode_base64((u_int8_t *) encrypted + i + 3, csalt, BCRYPT_MAXSALT); + encode_base64((u_int8_t *) encrypted + strlen(encrypted), ciphertext, + 4 * BCRYPT_BLOCKS - 1); + return encrypted; +} + +static void +encode_base64(u_int8_t *buffer, u_int8_t *data, u_int16_t len) +{ + u_int8_t *bp = buffer; + u_int8_t *p = data; + u_int8_t c1, c2; + while (p < data + len) { + c1 = *p++; + *bp++ = Base64Code[(c1 >> 2)]; + c1 = (c1 & 0x03) << 4; + if (p >= data + len) { + *bp++ = Base64Code[c1]; + break; + } + c2 = *p++; + c1 |= (c2 >> 4) & 0x0f; + *bp++ = Base64Code[c1]; + c1 = (c2 & 0x0f) << 2; + if (p >= data + len) { + *bp++ = Base64Code[c1]; + break; + } + c2 = *p++; + c1 |= (c2 >> 6) & 0x03; + *bp++ = Base64Code[c1]; + *bp++ = Base64Code[c2 & 0x3f]; + } + *bp = '\0'; +} + |