cups/hash.c

   1 /*
   2  * Hashing function for CUPS.
   3  *
   4  * Copyright 2015-2016 by Apple Inc.
   5  *
   6  * These coded instructions, statements, and computer programs are the
   7  * property of Apple Inc. and are protected by Federal copyright
   8  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
   9  * which should have been included with this file.  If this file is
  10  * missing or damaged, see the license at "http://www.cups.org/".
  11  *
  12  * This file is subject to the Apple OS-Developed Software exception.
  13  */
  14
  15 /*
  16  * Include necessary headers...
  17  */
  18
  19 #include "cups-private.h"
  20 #ifdef __APPLE__
  21 #  include <CommonCrypto/CommonDigest.h>
  22 #elif defined(HAVE_GNUTLS)
  23 #  include <gnutls/crypto.h>
  24 #endif /* __APPLE__ */
  25
  26
  27 /*
  28  * 'cupsHashData()' - Perform a hash function on the given data.
  29  *
  30  * The "algorithm" argument can be any of the registered, non-deprecated IPP
  31  * hash algorithms for the "job-password-encryption" attribute, including
  32  * "sha" for SHA-1, "sha-256" for SHA2-256, etc.
  33  *
  34  * The "hash" argument points to a buffer of "hashsize" bytes and should be at
  35  * least 64 bytes in length for all of the supported algorithms.
  36  *
  37  * The returned hash is binary data.
  38  *
  39  * @since CUPS 2.2/macOS 10.12@
  40  */
  41
  42 ssize_t                                 /* O - Size of hash or -1 on error */
  43 cupsHashData(const char    *algorithm,  /* I - Algorithm name */
  44              const void    *data,       /* I - Data to hash */
  45              size_t        datalen,     /* I - Length of data to hash */
  46              unsigned char *hash,       /* I - Hash buffer */
  47              size_t        hashsize)    /* I - Size of hash buffer */
  48 {
  49   if (!algorithm || !data || datalen == 0 || !hash || hashsize == 0)
  50   {
  51     _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Bad arguments to function"), 1);
  52     return (-1);
  53   }
  54
  55 #ifdef __APPLE__
  56   if (!strcmp(algorithm, "sha"))
  57   {
  58    /*
  59     * SHA-1...
  60     */
  61
  62     CC_SHA1_CTX ctx;                    /* SHA-1 context */
  63
  64     if (hashsize < CC_SHA1_DIGEST_LENGTH)
  65       goto too_small;
  66
  67     CC_SHA1_Init(&ctx);
  68     CC_SHA1_Update(&ctx, data, (CC_LONG)datalen);
  69     CC_SHA1_Final(hash, &ctx);
  70
  71     return (CC_SHA1_DIGEST_LENGTH);
  72   }
  73   else if (!strcmp(algorithm, "sha2-224"))
  74   {
  75     CC_SHA256_CTX       ctx;            /* SHA-224 context */
  76
  77     if (hashsize < CC_SHA224_DIGEST_LENGTH)
  78       goto too_small;
  79
  80     CC_SHA224_Init(&ctx);
  81     CC_SHA224_Update(&ctx, data, (CC_LONG)datalen);
  82     CC_SHA224_Final(hash, &ctx);
  83
  84     return (CC_SHA224_DIGEST_LENGTH);
  85   }
  86   else if (!strcmp(algorithm, "sha2-256"))
  87   {
  88     CC_SHA256_CTX       ctx;            /* SHA-256 context */
  89
  90     if (hashsize < CC_SHA256_DIGEST_LENGTH)
  91       goto too_small;
  92
  93     CC_SHA256_Init(&ctx);
  94     CC_SHA256_Update(&ctx, data, (CC_LONG)datalen);
  95     CC_SHA256_Final(hash, &ctx);
  96
  97     return (CC_SHA256_DIGEST_LENGTH);
  98   }
  99   else if (!strcmp(algorithm, "sha2-384"))
 100   {
 101     CC_SHA512_CTX       ctx;            /* SHA-384 context */
 102
 103     if (hashsize < CC_SHA384_DIGEST_LENGTH)
 104       goto too_small;
 105
 106     CC_SHA384_Init(&ctx);
 107     CC_SHA384_Update(&ctx, data, (CC_LONG)datalen);
 108     CC_SHA384_Final(hash, &ctx);
 109
 110     return (CC_SHA384_DIGEST_LENGTH);
 111   }
 112   else if (!strcmp(algorithm, "sha2-512"))
 113   {
 114     CC_SHA512_CTX       ctx;            /* SHA-512 context */
 115
 116     if (hashsize < CC_SHA512_DIGEST_LENGTH)
 117       goto too_small;
 118
 119     CC_SHA512_Init(&ctx);
 120     CC_SHA512_Update(&ctx, data, (CC_LONG)datalen);
 121     CC_SHA512_Final(hash, &ctx);
 122
 123     return (CC_SHA512_DIGEST_LENGTH);
 124   }
 125   else if (!strcmp(algorithm, "sha2-512_224"))
 126   {
 127     CC_SHA512_CTX       ctx;            /* SHA-512 context */
 128     unsigned char       temp[CC_SHA512_DIGEST_LENGTH];
 129                                         /* SHA-512 hash */
 130
 131    /*
 132     * SHA2-512 truncated to 224 bits (28 bytes)...
 133     */
 134
 135     if (hashsize < CC_SHA224_DIGEST_LENGTH)
 136       goto too_small;
 137
 138     CC_SHA512_Init(&ctx);
 139     CC_SHA512_Update(&ctx, data, (CC_LONG)datalen);
 140     CC_SHA512_Final(temp, &ctx);
 141
 142     memcpy(hash, temp, CC_SHA224_DIGEST_LENGTH);
 143
 144     return (CC_SHA224_DIGEST_LENGTH);
 145   }
 146   else if (!strcmp(algorithm, "sha2-512_256"))
 147   {
 148     CC_SHA512_CTX       ctx;            /* SHA-512 context */
 149     unsigned char       temp[CC_SHA512_DIGEST_LENGTH];
 150                                         /* SHA-512 hash */
 151
 152    /*
 153     * SHA2-512 truncated to 256 bits (32 bytes)...
 154     */
 155
 156     if (hashsize < CC_SHA256_DIGEST_LENGTH)
 157       goto too_small;
 158
 159     CC_SHA512_Init(&ctx);
 160     CC_SHA512_Update(&ctx, data, (CC_LONG)datalen);
 161     CC_SHA512_Final(temp, &ctx);
 162
 163     memcpy(hash, temp, CC_SHA256_DIGEST_LENGTH);
 164
 165     return (CC_SHA256_DIGEST_LENGTH);
 166   }
 167
 168 #elif defined(HAVE_GNUTLS)
 169   gnutls_digest_algorithm_t alg = GNUTLS_DIG_UNKNOWN;
 170                                         /* Algorithm */
 171   unsigned char temp[64];               /* Temporary hash buffer */
 172   size_t        tempsize = 0;           /* Truncate to this size? */
 173
 174   if (!strcmp(algorithm, "sha"))
 175     alg = GNUTLS_DIG_SHA1;
 176   else if (!strcmp(algorithm, "sha2-224"))
 177     alg = GNUTLS_DIG_SHA224;
 178   else if (!strcmp(algorithm, "sha2-256"))
 179     alg = GNUTLS_DIG_SHA256;
 180   else if (!strcmp(algorithm, "sha2-384"))
 181     alg = GNUTLS_DIG_SHA384;
 182   else if (!strcmp(algorithm, "sha2-512"))
 183     alg = GNUTLS_DIG_SHA512;
 184   else if (!strcmp(algorithm, "sha2-512_224"))
 185   {
 186     alg      = GNUTLS_DIG_SHA512;
 187     tempsize = 28;
 188   }
 189   else if (!strcmp(algorithm, "sha2-512_256"))
 190   {
 191     alg      = GNUTLS_DIG_SHA512;
 192     tempsize = 32;
 193   }
 194
 195   if (alg != GNUTLS_DIG_UNKNOWN)
 196   {
 197     if (tempsize > 0)
 198     {
 199      /*
 200       * Truncate result to tempsize bytes...
 201       */
 202
 203       if (hashsize < tempsize)
 204         goto too_small;
 205
 206       gnutls_hash_fast(alg, data, datalen, temp);
 207       memcpy(hash, temp, tempsize);
 208
 209       return ((ssize_t)tempsize);
 210     }
 211
 212     if (hashsize < gnutls_hash_get_len(alg))
 213       goto too_small;
 214
 215     gnutls_hash_fast(alg, data, datalen, hash);
 216
 217     return (gnutls_hash_get_len(alg));
 218   }
 219
 220 #else
 221  /*
 222   * No hash support without CommonCrypto or GNU TLS...
 223   */
 224
 225   if (hashsize < 64)
 226     goto too_small;
 227 #endif /* __APPLE__ */
 228
 229  /*
 230   * Unknown hash algorithm...
 231   */
 232
 233   _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Unknown hash algorithm."), 1);
 234
 235   return (-1);
 236
 237  /*
 238   * We get here if the buffer is too small.
 239   */
 240
 241   too_small:
 242
 243   _cupsSetError(IPP_STATUS_ERROR_INTERNAL, _("Hash buffer too small."), 1);
 244   return (-1);
 245 }