OSX/utilities/src/der_dictionary.c

   1 /*
   2  * Copyright (c) 2012-2014 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 <stdio.h>
  26
  27 #include "utilities/SecCFRelease.h"
  28 #include "utilities/der_plist.h"
  29 #include "utilities/der_plist_internal.h"
  30 #include "utilities/SecCFWrappers.h"
  31
  32 #include <corecrypto/ccder.h>
  33 #include <CoreFoundation/CoreFoundation.h>
  34
  35 static const uint8_t* der_decode_key_value(CFAllocatorRef allocator, CFOptionFlags mutability,
  36                                            CFPropertyListRef* key, CFPropertyListRef* value, CFErrorRef *error,
  37                                            const uint8_t* der, const uint8_t *der_end)
  38 {
  39     const uint8_t *payload_end = 0;
  40     const uint8_t *payload = ccder_decode_constructed_tl(CCDER_CONSTRUCTED_SEQUENCE, &payload_end, der, der_end);
  41
  42     if (NULL == payload) {
  43         SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding, expected CCDER_CONSTRUCTED_SEQUENCE"), NULL, error);
  44         return NULL;
  45     }
  46
  47     CFTypeRef keyObject = NULL;
  48     CFTypeRef valueObject = NULL;
  49
  50
  51     payload = der_decode_plist(allocator, mutability, &keyObject, error, payload, payload_end);
  52     payload = der_decode_plist(allocator, mutability, &valueObject, error, payload, payload_end);
  53
  54     if (payload != NULL) {
  55         *key = keyObject;
  56         *value = valueObject;
  57     } else {
  58         CFReleaseNull(keyObject);
  59         CFReleaseNull(valueObject);
  60     }
  61     return payload;
  62 }
  63
  64 const uint8_t* der_decode_dictionary(CFAllocatorRef allocator, CFOptionFlags mutability,
  65                                      CFDictionaryRef* dictionary, CFErrorRef *error,
  66                                      const uint8_t* der, const uint8_t *der_end)
  67 {
  68     if (NULL == der)
  69         return NULL;
  70
  71     const uint8_t *payload_end = 0;
  72     const uint8_t *payload = ccder_decode_constructed_tl(CCDER_CONSTRUCTED_SET, &payload_end, der, der_end);
  73
  74     if (NULL == payload) {
  75         SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding, expected CCDER_CONSTRUCTED_SET"), NULL, error);
  76         return NULL;
  77     }
  78
  79
  80     CFMutableDictionaryRef dict = CFDictionaryCreateMutable(allocator, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
  81
  82     if (NULL == dict) {
  83         SecCFDERCreateError(kSecDERErrorAllocationFailure, CFSTR("Failed to create dictionary"), NULL, error);
  84         payload = NULL;
  85         goto exit;
  86     }
  87
  88     while (payload != NULL && payload < payload_end) {
  89         CFTypeRef key = NULL;
  90         CFTypeRef value = NULL;
  91
  92         payload = der_decode_key_value(allocator, mutability, &key, &value, error, payload, payload_end);
  93
  94         if (payload) {
  95             CFDictionaryAddValue(dict, key, value);
  96         }
  97
  98         CFReleaseNull(key);
  99         CFReleaseNull(value);
 100     }
 101
 102
 103 exit:
 104     if (payload == payload_end) {
 105         *dictionary = dict;
 106         dict = NULL;
 107     }
 108
 109     CFReleaseNull(dict);
 110
 111     return payload;
 112 }
 113
 114 struct size_context {
 115     bool   success;
 116     size_t size;
 117     CFErrorRef *error;
 118 };
 119
 120 static size_t der_sizeof_key_value(CFTypeRef key, CFTypeRef value, CFErrorRef *error) {
 121     size_t key_size = der_sizeof_plist(key, error);
 122     if (key_size == 0) {
 123         return 0;
 124     }
 125     size_t value_size = der_sizeof_plist(value, error);
 126     if (value_size == 0) {
 127         return 0;
 128     }
 129     return ccder_sizeof(CCDER_CONSTRUCTED_SEQUENCE, key_size + value_size);
 130 }
 131
 132 static void add_key_value_size(const void *key_void, const void *value_void, void *context_void)
 133 {
 134     CFTypeRef key = (CFTypeRef) key_void;
 135     CFTypeRef value = (CFTypeRef) value_void;
 136     struct size_context *context = (struct size_context*) context_void;
 137
 138     if (!context->success)
 139         return;
 140
 141     size_t kv_size = der_sizeof_key_value(key, value, context->error);
 142     if (kv_size == 0) {
 143         context->success = false;
 144         return;
 145     }
 146
 147     context->size += kv_size;
 148 }
 149
 150 size_t der_sizeof_dictionary(CFDictionaryRef dict, CFErrorRef *error)
 151 {
 152     struct size_context context = { .success = true, .size = 0, .error = error };
 153
 154
 155     CFDictionaryApplyFunction(dict, add_key_value_size, &context);
 156
 157     if (!context.success)
 158         return 0;
 159
 160     return ccder_sizeof(CCDER_CONSTRUCTED_SET, context.size);
 161 }
 162
 163 static uint8_t* der_encode_key_value(CFPropertyListRef key, CFPropertyListRef value, CFErrorRef *error,
 164                                      const uint8_t* der, uint8_t *der_end)
 165 {
 166     return ccder_encode_constructed_tl(CCDER_CONSTRUCTED_SEQUENCE, der_end, der,
 167            der_encode_plist(key, error, der,
 168            der_encode_plist(value, error, der, der_end)));
 169 }
 170
 171 struct encode_context {
 172     bool         success;
 173     CFErrorRef * error;
 174     CFMutableArrayRef list;
 175     CFAllocatorRef allocator;
 176 };
 177
 178 static void add_sequence_to_array(const void *key_void, const void *value_void, void *context_void)
 179 {
 180     struct encode_context *context = (struct encode_context *) context_void;
 181     if (context->success) {
 182         CFTypeRef key = (CFTypeRef) key_void;
 183         CFTypeRef value = (CFTypeRef) value_void;
 184
 185         size_t der_size = der_sizeof_key_value(key, value, context->error);
 186         if (der_size == 0) {
 187             context-> success = false;
 188         } else {
 189             CFMutableDataRef encoded_kv = CFDataCreateMutable(context->allocator, der_size);
 190             CFDataSetLength(encoded_kv, der_size);
 191
 192             uint8_t* const encode_begin = CFDataGetMutableBytePtr(encoded_kv);
 193             uint8_t* encode_end = encode_begin + der_size;
 194
 195             encode_end = der_encode_key_value(key, value, context->error, encode_begin, encode_end);
 196
 197             if (encode_end != NULL) {
 198                 CFDataDeleteBytes(encoded_kv, CFRangeMake(0, (encode_end - encode_begin)));
 199                 CFArrayAppendValue(context->list, encoded_kv);
 200             } else {
 201                 context-> success = false;
 202             }
 203
 204             CFReleaseNull(encoded_kv);
 205         }
 206     }
 207 }
 208
 209 static CFComparisonResult cfdata_compare_contents(const void *val1, const void *val2, void *context __unused)
 210 {
 211     return CFDataCompare((CFDataRef) val1, (CFDataRef) val2);
 212 }
 213
 214
 215 uint8_t* der_encode_dictionary(CFDictionaryRef dictionary, CFErrorRef *error,
 216                                const uint8_t *der, uint8_t *der_end)
 217 {
 218     CFMutableArrayRef elements = CFArrayCreateMutable(NULL, 0, &kCFTypeArrayCallBacks);
 219
 220     struct encode_context context = { .success = true, .error = error, .list = elements };
 221     CFDictionaryApplyFunction(dictionary, add_sequence_to_array, &context);
 222
 223     if (!context.success) {
 224         CFReleaseNull(elements);
 225         return NULL;
 226     }
 227
 228     CFRange allOfThem = CFRangeMake(0, CFArrayGetCount(elements));
 229
 230     CFArraySortValues(elements, allOfThem, cfdata_compare_contents, NULL);
 231
 232     uint8_t* original_der_end = der_end;
 233
 234     for(CFIndex position = CFArrayGetCount(elements); position > 0;) {
 235         --position;
 236         CFDataRef data = CFArrayGetValueAtIndex(elements, position);
 237         der_end = ccder_encode_body(CFDataGetLength(data), CFDataGetBytePtr(data), der, der_end);
 238     }
 239
 240     CFReleaseNull(elements);
 241
 242     return ccder_encode_constructed_tl(CCDER_CONSTRUCTED_SET, original_der_end, der, der_end);
 243
 244 }