1 /* 2 * ---------------------------------------------------------------------------- 3 * "THE BEER-WARE LICENSE" (Revision 42): 4 * <phk (at) login.dknet.dk> wrote this file. As long as you retain this 5 * notice you can do whatever you want with this stuff. If we meet some 6 * day, and you think this stuff is worth it, you can buy me a beer in 7 * return. Poul-Henning Kamp 8 * ---------------------------------------------------------------------------- 9 */ 10 11 #include "includes.h" 12 13 #if defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) 14 #include <sys/types.h> 15 16 #include <string.h> 17 18 #include <openssl/md5.h> 19 20 /* 0 ... 63 => ascii - 64 */ 21 static unsigned char itoa64[] = 22 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 23 24 static char *magic = "$1$"; 25 26 static char * 27 to64(unsigned long v, int n) 28 { 29 static char buf[5]; 30 char *s = buf; 31 32 if (n > 4) 33 return (NULL); 34 35 memset(buf, '\0', sizeof(buf)); 36 while (--n >= 0) { 37 *s++ = itoa64[v&0x3f]; 38 v >>= 6; 39 } 40 41 return (buf); 42 } 43 44 int 45 is_md5_salt(const char *salt) 46 { 47 return (strncmp(salt, magic, strlen(magic)) == 0); 48 } 49 50 char * 51 md5_crypt(const char *pw, const char *salt) 52 { 53 static char passwd[120], salt_copy[9], *p; 54 static const char *sp, *ep; 55 unsigned char final[16]; 56 int sl, pl, i, j; 57 MD5_CTX ctx, ctx1; 58 unsigned long l; 59 60 /* Refine the Salt first */ 61 sp = salt; 62 63 /* If it starts with the magic string, then skip that */ 64 if(strncmp(sp, magic, strlen(magic)) == 0) 65 sp += strlen(magic); 66 67 /* It stops at the first '$', max 8 chars */ 68 for (ep = sp; *ep != '$'; ep++) { 69 if (*ep == '\0' || ep >= (sp + 8)) 70 return (NULL); 71 } 72 73 /* get the length of the true salt */ 74 sl = ep - sp; 75 76 /* Stash the salt */ 77 memcpy(salt_copy, sp, sl); 78 salt_copy[sl] = '\0'; 79 80 MD5_Init(&ctx); 81 82 /* The password first, since that is what is most unknown */ 83 MD5_Update(&ctx, pw, strlen(pw)); 84 85 /* Then our magic string */ 86 MD5_Update(&ctx, magic, strlen(magic)); 87 88 /* Then the raw salt */ 89 MD5_Update(&ctx, sp, sl); 90 91 /* Then just as many characters of the MD5(pw, salt, pw) */ 92 MD5_Init(&ctx1); 93 MD5_Update(&ctx1, pw, strlen(pw)); 94 MD5_Update(&ctx1, sp, sl); 95 MD5_Update(&ctx1, pw, strlen(pw)); 96 MD5_Final(final, &ctx1); 97 98 for(pl = strlen(pw); pl > 0; pl -= 16) 99 MD5_Update(&ctx, final, pl > 16 ? 16 : pl); 100 101 /* Don't leave anything around in vm they could use. */ 102 memset(final, '\0', sizeof final); 103 104 /* Then something really weird... */ 105 for (j = 0, i = strlen(pw); i != 0; i >>= 1) 106 if (i & 1) 107 MD5_Update(&ctx, final + j, 1); 108 else 109 MD5_Update(&ctx, pw + j, 1); 110 111 /* Now make the output string */ 112 snprintf(passwd, sizeof(passwd), "%s%s$", magic, salt_copy); 113 114 MD5_Final(final, &ctx); 115 116 /* 117 * and now, just to make sure things don't run too fast 118 * On a 60 Mhz Pentium this takes 34 msec, so you would 119 * need 30 seconds to build a 1000 entry dictionary... 120 */ 121 for(i = 0; i < 1000; i++) { 122 MD5_Init(&ctx1); 123 if (i & 1) 124 MD5_Update(&ctx1, pw, strlen(pw)); 125 else 126 MD5_Update(&ctx1, final, 16); 127 128 if (i % 3) 129 MD5_Update(&ctx1, sp, sl); 130 131 if (i % 7) 132 MD5_Update(&ctx1, pw, strlen(pw)); 133 134 if (i & 1) 135 MD5_Update(&ctx1, final, 16); 136 else 137 MD5_Update(&ctx1, pw, strlen(pw)); 138 139 MD5_Final(final, &ctx1); 140 } 141 142 p = passwd + strlen(passwd); 143 144 l = (final[ 0]<<16) | (final[ 6]<<8) | final[12]; 145 strlcat(passwd, to64(l, 4), sizeof(passwd)); 146 l = (final[ 1]<<16) | (final[ 7]<<8) | final[13]; 147 strlcat(passwd, to64(l, 4), sizeof(passwd)); 148 l = (final[ 2]<<16) | (final[ 8]<<8) | final[14]; 149 strlcat(passwd, to64(l, 4), sizeof(passwd)); 150 l = (final[ 3]<<16) | (final[ 9]<<8) | final[15]; 151 strlcat(passwd, to64(l, 4), sizeof(passwd)); 152 l = (final[ 4]<<16) | (final[10]<<8) | final[ 5]; 153 strlcat(passwd, to64(l, 4), sizeof(passwd)); 154 l = final[11] ; 155 strlcat(passwd, to64(l, 2), sizeof(passwd)); 156 157 /* Don't leave anything around in vm they could use. */ 158 memset(final, 0, sizeof(final)); 159 memset(salt_copy, 0, sizeof(salt_copy)); 160 memset(&ctx, 0, sizeof(ctx)); 161 memset(&ctx1, 0, sizeof(ctx1)); 162 (void)to64(0, 4); 163 164 return (passwd); 165 } 166 167 #endif /* defined(HAVE_MD5_PASSWORDS) && !defined(HAVE_MD5_CRYPT) */ 168
