cups/md5passwd.c

   1 /*
   2  * MD5 password support for CUPS.
   3  *
   4  * Copyright 2007-2010 by Apple Inc.
   5  * Copyright 1997-2005 by Easy Software Products.
   6  *
   7  * These coded instructions, statements, and computer programs are the
   8  * property of Apple Inc. and are protected by Federal copyright
   9  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  10  * which should have been included with this file.  If this file is
  11  * file is missing or damaged, see the license at "http://www.cups.org/".
  12  *
  13  * This file is subject to the Apple OS-Developed Software exception.
  14  */
  15
  16 /*
  17  * Include necessary headers...
  18  */
  19
  20 #include "http-private.h"
  21 #include "string-private.h"
  22
  23
  24 /*
  25  * 'httpMD5()' - Compute the MD5 sum of the username:group:password.
  26  */
  27
  28 char *                                  /* O - MD5 sum */
  29 httpMD5(const char *username,           /* I - User name */
  30         const char *realm,              /* I - Realm name */
  31         const char *passwd,             /* I - Password string */
  32         char       md5[33])             /* O - MD5 string */
  33 {
  34   _cups_md5_state_t     state;          /* MD5 state info */
  35   unsigned char         sum[16];        /* Sum data */
  36   char                  line[256];      /* Line to sum */
  37
  38
  39  /*
  40   * Compute the MD5 sum of the user name, group name, and password.
  41   */
  42
  43   snprintf(line, sizeof(line), "%s:%s:%s", username, realm, passwd);
  44   _cupsMD5Init(&state);
  45   _cupsMD5Append(&state, (unsigned char *)line, (int)strlen(line));
  46   _cupsMD5Finish(&state, sum);
  47
  48  /*
  49   * Return the sum...
  50   */
  51
  52   return (httpMD5String(sum, md5));
  53 }
  54
  55
  56 /*
  57  * 'httpMD5Final()' - Combine the MD5 sum of the username, group, and password
  58  *                    with the server-supplied nonce value, method, and
  59  *                    request-uri.
  60  */
  61
  62 char *                                  /* O - New sum */
  63 httpMD5Final(const char *nonce,         /* I - Server nonce value */
  64              const char *method,        /* I - METHOD (GET, POST, etc.) */
  65              const char *resource,      /* I - Resource path */
  66              char       md5[33])        /* IO - MD5 sum */
  67 {
  68   _cups_md5_state_t     state;          /* MD5 state info */
  69   unsigned char         sum[16];        /* Sum data */
  70   char                  line[1024];     /* Line of data */
  71   char                  a2[33];         /* Hash of method and resource */
  72
  73
  74  /*
  75   * First compute the MD5 sum of the method and resource...
  76   */
  77
  78   snprintf(line, sizeof(line), "%s:%s", method, resource);
  79   _cupsMD5Init(&state);
  80   _cupsMD5Append(&state, (unsigned char *)line, (int)strlen(line));
  81   _cupsMD5Finish(&state, sum);
  82   httpMD5String(sum, a2);
  83
  84  /*
  85   * Then combine A1 (MD5 of username, realm, and password) with the nonce
  86   * and A2 (method + resource) values to get the final MD5 sum for the
  87   * request...
  88   */
  89
  90   snprintf(line, sizeof(line), "%s:%s:%s", md5, nonce, a2);
  91
  92   _cupsMD5Init(&state);
  93   _cupsMD5Append(&state, (unsigned char *)line, (int)strlen(line));
  94   _cupsMD5Finish(&state, sum);
  95
  96   return (httpMD5String(sum, md5));
  97 }
  98
  99
 100 /*
 101  * 'httpMD5String()' - Convert an MD5 sum to a character string.
 102  */
 103
 104 char *                                  /* O - MD5 sum in hex */
 105 httpMD5String(const unsigned char *sum, /* I - MD5 sum data */
 106               char                md5[33])
 107                                         /* O - MD5 sum in hex */
 108 {
 109   int           i;                      /* Looping var */
 110   char          *md5ptr;                /* Pointer into MD5 string */
 111   static const char hex[] = "0123456789abcdef";
 112                                         /* Hex digits */
 113
 114
 115  /*
 116   * Convert the MD5 sum to hexadecimal...
 117   */
 118
 119   for (i = 16, md5ptr = md5; i > 0; i --, sum ++)
 120   {
 121     *md5ptr++ = hex[*sum >> 4];
 122     *md5ptr++ = hex[*sum & 15];
 123   }
 124
 125   *md5ptr = '\0';
 126
 127   return (md5);
 128 }