1 /* $NetBSD: md5crypt.c,v 1.7 2003/08/06 08:37:19 jdolecek Exp $ */ 2 3 /* 4 * ---------------------------------------------------------------------------- 5 * "THE BEER-WARE LICENSE" (Revision 42): 6 * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you 7 * can do whatever you want with this stuff. If we meet some day, and you think 8 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 9 * ---------------------------------------------------------------------------- 10 * 11 * from FreeBSD: crypt.c,v 1.5 1996/10/14 08:34:02 phk Exp 12 * via OpenBSD: md5crypt.c,v 1.9 1997/07/23 20:58:27 kstailey Exp 13 * 14 */ 15 16 #include <sys/cdefs.h> 17 #if !defined(lint) 18 __RCSID("$NetBSD: md5crypt.c,v 1.7 2003/08/06 08:37:19 jdolecek Exp $"); 19 #endif /* not lint */ 20 21 /* 22 * NOTE: We are also built for inclusion in libcrypto; when built for that 23 * environment, use the libcrypto versions of the MD5 routines, so save 24 * having to pull two versions into the same program. 25 */ 26 27 #include <unistd.h> 28 #include <stdio.h> 29 #include <string.h> 30 #ifdef libcrypto 31 #include <openssl/md5.h> 32 #else 33 #include <md5.h> 34 #endif 35 #include <string.h> 36 37 #define MD5_MAGIC "$1$" 38 #define MD5_MAGIC_LEN 3 39 40 char *__md5crypt(const char *pw, const char *salt); /* XXX */ 41 42 static const unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */ 43 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 44 45 #ifdef libcrypto 46 #define INIT(x) MD5_Init((x)) 47 #define UPDATE(x, b, l) MD5_Update((x), (b), (l)) 48 #define FINAL(v, x) MD5_Final((v), (x)) 49 #else 50 #define INIT(x) MD5Init((x)) 51 #define UPDATE(x, b, l) MD5Update((x), (b), (l)) 52 #define FINAL(v, x) MD5Final((v), (x)) 53 #endif 54 55 static void 56 to64(char *s, u_int32_t v, int n) 57 { 58 59 while (--n >= 0) { 60 *s++ = itoa64[v & 0x3f]; 61 v >>= 6; 62 } 63 } 64 65 /* 66 * MD5 password encryption. 67 */ 68 char * 69 __md5crypt(const char *pw, const char *salt) 70 { 71 static char passwd[120], *p; 72 const char *sp, *ep; 73 unsigned char final[16]; 74 unsigned int i, sl, pwl; 75 MD5_CTX ctx, ctx1; 76 u_int32_t l; 77 int pl; 78 79 pwl = strlen(pw); 80 81 /* Refine the salt first */ 82 sp = salt; 83 84 /* If it starts with the magic string, then skip that */ 85 if (strncmp(sp, MD5_MAGIC, MD5_MAGIC_LEN) == 0) 86 sp += MD5_MAGIC_LEN; 87 88 /* It stops at the first '$', max 8 chars */ 89 for (ep = sp; *ep != '\0' && *ep != '$' && ep < (sp + 8); ep++) 90 continue; 91 92 /* get the length of the true salt */ 93 sl = ep - sp; 94 95 INIT(&ctx); 96 97 /* The password first, since that is what is most unknown */ 98 UPDATE(&ctx, (const unsigned char *)pw, pwl); 99 100 /* Then our magic string */ 101 UPDATE(&ctx, (const unsigned char *)MD5_MAGIC, MD5_MAGIC_LEN); 102 103 /* Then the raw salt */ 104 UPDATE(&ctx, (const unsigned char *)sp, sl); 105 106 /* Then just as many characters of the MD5(pw,salt,pw) */ 107 INIT(&ctx1); 108 UPDATE(&ctx1, (const unsigned char *)pw, pwl); 109 UPDATE(&ctx1, (const unsigned char *)sp, sl); 110 UPDATE(&ctx1, (const unsigned char *)pw, pwl); 111 FINAL(final, &ctx1); 112 113 for (pl = pwl; pl > 0; pl -= 16) 114 UPDATE(&ctx, final, (unsigned int)(pl > 16 ? 16 : pl)); 115 116 /* Don't leave anything around in vm they could use. */ 117 memset(final, 0, sizeof(final)); 118 119 /* Then something really weird... */ 120 for (i = pwl; i != 0; i >>= 1) 121 if ((i & 1) != 0) 122 UPDATE(&ctx, final, 1); 123 else 124 UPDATE(&ctx, (const unsigned char *)pw, 1); 125 126 /* Now make the output string */ 127 memcpy(passwd, MD5_MAGIC, MD5_MAGIC_LEN); 128 strlcpy(passwd + MD5_MAGIC_LEN, sp, sl + 1); 129 strlcat(passwd, "$", sizeof(passwd)); 130 131 FINAL(final, &ctx); 132 133 /* 134 * And now, just to make sure things don't run too fast. On a 60 MHz 135 * Pentium this takes 34 msec, so you would need 30 seconds to build 136 * a 1000 entry dictionary... 137 */ 138 for (i = 0; i < 1000; i++) { 139 INIT(&ctx1); 140 141 if ((i & 1) != 0) 142 UPDATE(&ctx1, (const unsigned char *)pw, pwl); 143 else 144 UPDATE(&ctx1, final, 16); 145 146 if ((i % 3) != 0) 147 UPDATE(&ctx1, (const unsigned char *)sp, sl); 148 149 if ((i % 7) != 0) 150 UPDATE(&ctx1, (const unsigned char *)pw, pwl); 151 152 if ((i & 1) != 0) 153 UPDATE(&ctx1, final, 16); 154 else 155 UPDATE(&ctx1, (const unsigned char *)pw, pwl); 156 157 FINAL(final, &ctx1); 158 } 159 160 p = passwd + sl + MD5_MAGIC_LEN + 1; 161 162 l = (final[ 0]<<16) | (final[ 6]<<8) | final[12]; to64(p,l,4); p += 4; 163 l = (final[ 1]<<16) | (final[ 7]<<8) | final[13]; to64(p,l,4); p += 4; 164 l = (final[ 2]<<16) | (final[ 8]<<8) | final[14]; to64(p,l,4); p += 4; 165 l = (final[ 3]<<16) | (final[ 9]<<8) | final[15]; to64(p,l,4); p += 4; 166 l = (final[ 4]<<16) | (final[10]<<8) | final[ 5]; to64(p,l,4); p += 4; 167 l = final[11] ; to64(p,l,2); p += 2; 168 *p = '\0'; 169 170 /* Don't leave anything around in vm they could use. */ 171 memset(final, 0, sizeof(final)); 172 return (passwd); 173 } 174