OSX/libsecurity_transform/lib/Digest_block.c

   1 /*
   2  * Copyright (c) 2010-2011,2014 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24
  25 #include "Digest_block.h"
  26 #include "SecCustomTransform.h"
  27 #include <CommonCrypto/CommonDigest.h>
  28 #include "Utilities.h"
  29
  30 extern const CFStringRef kSecDigestMD2, kSecDigestMD4, kSecDigestMD5, kSecDigestSHA1, kSecDigestSHA2;
  31 extern const CFStringRef kSecDigestTypeAttribute, kSecDigestLengthAttribute;
  32
  33
  34 static CFStringRef kCustomDigestTransformName = CFSTR("com.apple.security.digest");
  35
  36 SecTransformRef SecDigestTransformCreate_block(SecProviderRef device, CFTypeRef digestType, CFIndex digestLength, CFErrorRef* error) {
  37         static dispatch_once_t inited;
  38         __block CFStringRef current_algo;
  39         __block CFIndex current_length;
  40
  41         dispatch_once(&inited, ^{
  42                 SecTransformRegister(kCustomDigestTransformName, ^(CFStringRef name, SecTransformRebindActionBlock rebind) {
  43                         rebind(kSecTransformActionProcessData, NULL, ^(SecTransformRef tr, CFDataRef d, SecTransformSendAttribute set) {
  44                                 set(kSecDigestTypeAttribute, kSecDigestSHA2);
  45                         });
  46                         rebind(SecTransformSetAttributeAction, NULL, ^(SecTransformRef tr, CFStringRef name, CFTypeRef value, SecTransformSendAttribute set) {
  47                                 Boolean algo_changed = FALSE;
  48                                 if (name == kSecDigestTypeAttribute || CFStringCompare(kSecDigestTypeAttribute, name, 0) == kCFCompareEqualTo) {
  49                                         algo_changed = TRUE;
  50                                         current_algo = CFStringCreateCopy(NULL, (CFStringRef)value);
  51
  52                                 } else if (name == kSecDigestLengthAttribute || CFStringCompare(kSecDigestLengthAttribute, name, 0) == kCFCompareEqualTo) {
  53                                         algo_changed = TRUE;
  54                                         CFNumberGetValue(value, kCFNumberCFIndexType, &current_length);
  55                                 } else if (CFStringCompare(kSecTransformInputAttributeName, name, 0) == kCFCompareEqualTo) {
  56                                         return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidType, "The type %@ is invalid.", name);
  57                                 } else {
  58                                         return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidType, "The type %@ is invalid.", name);
  59                                 }
  60                                 if (!algo_changed) {
  61                                         return value;
  62                                 }
  63
  64                                 if (current_algo == kSecDigestSHA2 || CFStringCompare(current_algo, kSecDigestSHA2, 0) == kCFCompareEqualTo) {
  65                                         switch (current_length) {
  66                                                 case 0:
  67                                                 case 512: {
  68                                                         __block CC_SHA512_CTX cc_context;
  69                                                         CC_SHA512_Init(&cc_context);
  70                                                         rebind(kSecTransformActionProcessData, NULL, ^(SecTransformRef tr, CFDataRef d, SecTransformSendAttribute set) {
  71                                                                 if (d) {
  72                                                                         CC_SHA512_Update(&cc_context, CFDataGetBytePtr(d), CFDataGetLength(d));
  73                                                                         return SecTransformNoData();
  74                                                                 } else {
  75                                                                         u_int8_t digest_buffer[CC_SHA512_DIGEST_LENGTH];
  76
  77                                                                         CC_SHA512_Final(digest_buffer, &cc_context);
  78                                                                         set(kSecTransformOutputAttributeName, CFDataCreate(NULL, digest_buffer, CC_SHA512_DIGEST_LENGTH));
  79                                                                         return NULL;
  80                                                                 }
  81                                                         });
  82                                                         return value;
  83                                                 }
  84                                         }
  85                                         return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidLength, "Invalid length.");
  86                                 } else {
  87                                         return (CFTypeRef)CreateSecTransformErrorRef(kSecTransformErrorInvalidAlgorithm, "Invalid algorithm.");
  88                                 }
  89                         });
  90                 }, NULL);
  91         });
  92
  93         SecTransformRef dt = SecTransformCreate(kCustomDigestTransformName, NULL);
  94         SecTransformSetAttribute(dt, kSecDigestTypeAttribute, digestType, error);
  95         CFNumberRef dlen = CFNumberCreate(NULL, kCFNumberCFIndexType, &digestLength);
  96         SecTransformSetAttribute(dt, kSecDigestLengthAttribute, dlen, error);
  97         CFRelease(dlen);
  98
  99         return dt;
 100 }