| 1 | /* |
| 2 | ** Copyright 1998 - 1999 Double Precision, Inc. |
| 3 | ** See COPYING for distribution information. |
| 4 | */ |
| 5 | |
| 6 | #define MD5_INTERNAL |
| 7 | #include "md5.h" |
| 8 | #include <string.h> |
| 9 | |
| 10 | static const char rcsid[]="$Id: redhat-crypt-md5.c,v 1.3 1999/12/06 13:22:43 mrsam Exp $"; |
| 11 | |
| 12 | static char base64[]= |
| 13 | "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; |
| 14 | |
| 15 | char *md5_crypt_redhat(const char *pw, const char *salt) |
| 16 | { |
| 17 | struct MD5_CONTEXT outer_context, inner_context; |
| 18 | MD5_DIGEST digest; |
| 19 | unsigned pwl=strlen(pw); |
| 20 | unsigned l; |
| 21 | unsigned i, j; |
| 22 | char *p; |
| 23 | static char buffer[100]; |
| 24 | |
| 25 | if (*salt == '$' && salt[1] == '1' && salt[2] == '$') |
| 26 | salt += 3; |
| 27 | |
| 28 | for (l=0; l<8 && salt[l] && salt[l] != '$'; l++) |
| 29 | ; |
| 30 | |
| 31 | md5_context_init(&inner_context); |
| 32 | md5_context_hashstream(&inner_context, pw, pwl); |
| 33 | md5_context_hashstream(&inner_context, salt, l); |
| 34 | md5_context_hashstream(&inner_context, pw, pwl); |
| 35 | md5_context_endstream(&inner_context, pwl*2+l); |
| 36 | md5_context_digest(&inner_context, digest); |
| 37 | |
| 38 | md5_context_init(&outer_context); |
| 39 | md5_context_hashstream(&outer_context, pw, pwl); |
| 40 | md5_context_hashstream(&outer_context, "$1$", 3); |
| 41 | md5_context_hashstream(&outer_context, salt, l); |
| 42 | |
| 43 | for (i=pwl; i; ) |
| 44 | { |
| 45 | j=i; |
| 46 | if (j > 16) j=16; |
| 47 | md5_context_hashstream(&outer_context, digest, j); |
| 48 | i -= j; |
| 49 | } |
| 50 | |
| 51 | j=pwl*2+l+3; |
| 52 | |
| 53 | for (i=pwl; i; i >>= 1) |
| 54 | { |
| 55 | md5_context_hashstream(&outer_context, (i & 1) ? "": pw, 1); |
| 56 | ++j; |
| 57 | } |
| 58 | |
| 59 | |
| 60 | md5_context_endstream(&outer_context, j); |
| 61 | md5_context_digest(&outer_context, digest); |
| 62 | |
| 63 | for (i=0; i<1000; i++) |
| 64 | { |
| 65 | j=0; |
| 66 | |
| 67 | md5_context_init(&outer_context); |
| 68 | if (i & 1) |
| 69 | { |
| 70 | md5_context_hashstream(&outer_context, pw, pwl); |
| 71 | j += pwl; |
| 72 | } |
| 73 | else |
| 74 | { |
| 75 | md5_context_hashstream(&outer_context, digest, 16); |
| 76 | j += 16; |
| 77 | } |
| 78 | |
| 79 | if (i % 3) |
| 80 | { |
| 81 | md5_context_hashstream(&outer_context, salt, l); |
| 82 | j += l; |
| 83 | } |
| 84 | |
| 85 | if (i % 7) |
| 86 | { |
| 87 | md5_context_hashstream(&outer_context, pw, pwl); |
| 88 | j += pwl; |
| 89 | } |
| 90 | |
| 91 | if (i & 1) |
| 92 | { |
| 93 | md5_context_hashstream(&outer_context, digest, 16); |
| 94 | j += 16; |
| 95 | } |
| 96 | else |
| 97 | { |
| 98 | md5_context_hashstream(&outer_context, pw, pwl); |
| 99 | j += pwl; |
| 100 | } |
| 101 | |
| 102 | md5_context_endstream(&outer_context, j); |
| 103 | md5_context_digest(&outer_context, digest); |
| 104 | } |
| 105 | |
| 106 | strcpy(buffer, "$1$"); |
| 107 | strncat(buffer, salt, l); |
| 108 | strcat(buffer, "$"); |
| 109 | |
| 110 | p=buffer+strlen(buffer); |
| 111 | for (i=0; i<5; i++) |
| 112 | { |
| 113 | unsigned char *d=digest; |
| 114 | |
| 115 | j= (d[i] << 16) | (d[i+6] << 8) | d[i == 4 ? 5:12+i]; |
| 116 | *p++= base64[j & 63] ; j=j >> 6; |
| 117 | *p++= base64[j & 63] ; j=j >> 6; |
| 118 | *p++= base64[j & 63] ; j=j >> 6; |
| 119 | *p++= base64[j & 63]; |
| 120 | } |
| 121 | j=digest[11]; |
| 122 | *p++ = base64[j & 63]; j=j >> 6; |
| 123 | *p++ = base64[j & 63]; |
| 124 | *p=0; |
| 125 | return (buffer); |
| 126 | } |