diff options
Diffstat (limited to 'src/crypt/crypt_md5.c')
| -rw-r--r-- | src/crypt/crypt_md5.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/src/crypt/crypt_md5.c b/src/crypt/crypt_md5.c new file mode 100644 index 00000000..02f22444 --- /dev/null +++ b/src/crypt/crypt_md5.c @@ -0,0 +1,285 @@ +/* + * md5 crypt implementation + * + * original md5 crypt design is from Poul-Henning Kamp + * this implementation was created based on the code in freebsd + * at least 32bit int is assumed, key is limited and $1$ prefix is mandatory, + * on error "*" is returned + */ +#include <string.h> +#include <stdint.h> + +/* public domain md5 implementation based on rfc1321 and libtomcrypt */ + +struct md5 { + uint64_t len; /* processed message length */ + uint32_t h[4]; /* hash state */ + uint8_t buf[64]; /* message block buffer */ +}; + +static uint32_t rol(uint32_t n, int k) { return (n << k) | (n >> (32-k)); } +#define F(x,y,z) (z ^ (x & (y ^ z))) +#define G(x,y,z) (y ^ (z & (y ^ x))) +#define H(x,y,z) (x ^ y ^ z) +#define I(x,y,z) (y ^ (x | ~z)) +#define FF(a,b,c,d,w,s,t) a += F(b,c,d) + w + t; a = rol(a,s) + b +#define GG(a,b,c,d,w,s,t) a += G(b,c,d) + w + t; a = rol(a,s) + b +#define HH(a,b,c,d,w,s,t) a += H(b,c,d) + w + t; a = rol(a,s) + b +#define II(a,b,c,d,w,s,t) a += I(b,c,d) + w + t; a = rol(a,s) + b + +static const uint32_t tab[64] = { +0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, +0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, +0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, +0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, +0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, +0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, +0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, +0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 +}; + +static void processblock(struct md5 *s, const uint8_t *buf) +{ + uint32_t i, W[16], a, b, c, d; + + for (i = 0; i < 16; i++) { + W[i] = buf[4*i]; + W[i] |= (uint32_t)buf[4*i+1]<<8; + W[i] |= (uint32_t)buf[4*i+2]<<16; + W[i] |= (uint32_t)buf[4*i+3]<<24; + } + + a = s->h[0]; + b = s->h[1]; + c = s->h[2]; + d = s->h[3]; + + i = 0; + while (i < 16) { + FF(a,b,c,d, W[i], 7, tab[i]); i++; + FF(d,a,b,c, W[i], 12, tab[i]); i++; + FF(c,d,a,b, W[i], 17, tab[i]); i++; + FF(b,c,d,a, W[i], 22, tab[i]); i++; + } + while (i < 32) { + GG(a,b,c,d, W[(5*i+1)%16], 5, tab[i]); i++; + GG(d,a,b,c, W[(5*i+1)%16], 9, tab[i]); i++; + GG(c,d,a,b, W[(5*i+1)%16], 14, tab[i]); i++; + GG(b,c,d,a, W[(5*i+1)%16], 20, tab[i]); i++; + } + while (i < 48) { + HH(a,b,c,d, W[(3*i+5)%16], 4, tab[i]); i++; + HH(d,a,b,c, W[(3*i+5)%16], 11, tab[i]); i++; + HH(c,d,a,b, W[(3*i+5)%16], 16, tab[i]); i++; + HH(b,c,d,a, W[(3*i+5)%16], 23, tab[i]); i++; + } + while (i < 64) { + II(a,b,c,d, W[7*i%16], 6, tab[i]); i++; + II(d,a,b,c, W[7*i%16], 10, tab[i]); i++; + II(c,d,a,b, W[7*i%16], 15, tab[i]); i++; + II(b,c,d,a, W[7*i%16], 21, tab[i]); i++; + } + + s->h[0] += a; + s->h[1] += b; + s->h[2] += c; + s->h[3] += d; +} + +static void pad(struct md5 *s) +{ + unsigned r = s->len % 64; + + s->buf[r++] = 0x80; + if (r > 56) { + memset(s->buf + r, 0, 64 - r); + r = 0; + processblock(s, s->buf); + } + memset(s->buf + r, 0, 56 - r); + s->len *= 8; + s->buf[56] = s->len; + s->buf[57] = s->len >> 8; + s->buf[58] = s->len >> 16; + s->buf[59] = s->len >> 24; + s->buf[60] = s->len >> 32; + s->buf[61] = s->len >> 40; + s->buf[62] = s->len >> 48; + s->buf[63] = s->len >> 56; + processblock(s, s->buf); +} + +static void md5_init(struct md5 *s) +{ + s->len = 0; + s->h[0] = 0x67452301; + s->h[1] = 0xefcdab89; + s->h[2] = 0x98badcfe; + s->h[3] = 0x10325476; +} + +static void md5_sum(struct md5 *s, uint8_t md[16]) +{ + int i; + + pad(s); + for (i = 0; i < 4; i++) { + md[4*i] = s->h[i]; + md[4*i+1] = s->h[i] >> 8; + md[4*i+2] = s->h[i] >> 16; + md[4*i+3] = s->h[i] >> 24; + } +} + +static void md5_update(struct md5 *s, const void *m, unsigned long len) +{ + const uint8_t *p = m; + unsigned r = s->len % 64; + + s->len += len; + if (r) { + if (len < 64 - r) { + memcpy(s->buf + r, p, len); + return; + } + memcpy(s->buf + r, p, 64 - r); + len -= 64 - r; + p += 64 - r; + processblock(s, s->buf); + } + for (; len >= 64; len -= 64, p += 64) + processblock(s, p); + memcpy(s->buf, p, len); +} + +/*- + * Copyright (c) 2003 Poul-Henning Kamp + * 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 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 AUTHOR 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. + */ + +/* key limit is not part of the original design, added for DoS protection */ +#define KEY_MAX 30000 +#define SALT_MAX 8 + +static unsigned char b64[] = +"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; + +static char *to64(char *s, unsigned int u, int n) +{ + while (--n >= 0) { + *s++ = b64[u % 64]; + u /= 64; + } + return s; +} + +static char *md5crypt(const char *key, const char *setting, char *output) +{ + struct md5 ctx; + unsigned char md[16]; + unsigned int i, klen, slen; + const char *salt; + char *p; + + /* reject large keys */ + klen = strnlen(key, KEY_MAX+1); + if (klen > KEY_MAX) + return 0; + + /* setting: $1$salt$ (closing $ is optional) */ + if (strncmp(setting, "$1$", 3) != 0) + return 0; + salt = setting + 3; + for (i = 0; i < SALT_MAX && salt[i] && salt[i] != '$'; i++); + slen = i; + + /* md5(key salt key) */ + md5_init(&ctx); + md5_update(&ctx, key, klen); + md5_update(&ctx, salt, slen); + md5_update(&ctx, key, klen); + md5_sum(&ctx, md); + + /* md5(key $1$ salt repeated-md weird-key[0]-0) */ + md5_init(&ctx); + md5_update(&ctx, key, klen); + md5_update(&ctx, setting, 3 + slen); + for (i = klen; i > sizeof md; i -= sizeof md) + md5_update(&ctx, md, sizeof md); + md5_update(&ctx, md, i); + md[0] = 0; + for (i = klen; i; i >>= 1) + if (i & 1) + md5_update(&ctx, md, 1); + else + md5_update(&ctx, key, 1); + md5_sum(&ctx, md); + + /* md = f(md, key, salt) iteration */ + for (i = 0; i < 1000; i++) { + md5_init(&ctx); + if (i % 2) + md5_update(&ctx, key, klen); + else + md5_update(&ctx, md, sizeof md); + if (i % 3) + md5_update(&ctx, salt, slen); + if (i % 7) + md5_update(&ctx, key, klen); + if (i % 2) + md5_update(&ctx, md, sizeof md); + else + md5_update(&ctx, key, klen); + md5_sum(&ctx, md); + } + + /* output is $1$salt$hash */ + memcpy(output, setting, 3 + slen); + p = output + 3 + slen; + *p++ = '$'; + static const unsigned char perm[][3] = { + 0,6,12,1,7,13,2,8,14,3,9,15,4,10,5 }; + for (i=0; i<5; i++) p = to64(p, + (md[perm[i][0]]<<16)|(md[perm[i][1]]<<8)|md[perm[i][2]], 4); + p = to64(p, md[11], 2); + *p = 0; + + return output; +} + +char *__crypt_md5(const char *key, const char *setting, char *output) +{ + static const char testkey[] = "Xy01@#\x01\x02\x80\x7f\xff\r\n\x81\t !"; + static const char testsetting[] = "$1$abcd0123$"; + static const char testhash[] = "$1$abcd0123$9Qcg8DyviekV3tDGMZynJ1"; + char testbuf[64]; + char *p, *q; + + p = md5crypt(key, setting, output); + /* self test and stack cleanup */ + q = md5crypt(testkey, testsetting, testbuf); + if (!p || q != testbuf || memcmp(testbuf, testhash, sizeof testhash)) + return "*"; + return p; +} |