OSX/utilities/der_string.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
  31 #include <corecrypto/ccder.h>
  32 #include <CoreFoundation/CoreFoundation.h>
  33
  34
  35 const uint8_t* der_decode_string(CFAllocatorRef allocator,
  36                                  CFStringRef* string, CFErrorRef *error,
  37                                  const uint8_t* der, const uint8_t *der_end)
  38 {
  39     if (NULL == der) {
  40         SecCFDERCreateError(kSecDERErrorNullInput, CFSTR("null input"), NULL, error);
  41         return NULL;
  42     }
  43
  44     size_t payload_size = 0;
  45     const uint8_t *payload = ccder_decode_tl(CCDER_UTF8_STRING, &payload_size, der, der_end);
  46
  47     if (NULL == payload || (ssize_t) (der_end - payload) < (ssize_t) payload_size){
  48         SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown string encoding"), NULL, error);
  49         return NULL;
  50     }
  51
  52     *string = CFStringCreateWithBytes(allocator, payload, payload_size, kCFStringEncodingUTF8, false);
  53
  54     if (NULL == *string) {
  55         SecCFDERCreateError(kSecDERErrorAllocationFailure, CFSTR("String allocation failed"), NULL, error);
  56         return NULL;
  57     }
  58
  59     return payload + payload_size;
  60 }
  61
  62
  63 size_t der_sizeof_string(CFStringRef str, CFErrorRef *error)
  64 {
  65     const CFIndex str_length    = CFStringGetLength(str);
  66     const CFIndex maximum       = CFStringGetMaximumSizeForEncoding(str_length, kCFStringEncodingUTF8);
  67
  68     CFIndex encodedLen = 0;
  69     CFIndex converted = CFStringGetBytes(str, CFRangeMake(0, str_length), kCFStringEncodingUTF8, 0, false, NULL, maximum, &encodedLen);
  70
  71     return ccder_sizeof(CCDER_UTF8_STRING, (converted == str_length) ? encodedLen : 0);
  72 }
  73
  74
  75 uint8_t* der_encode_string(CFStringRef string, CFErrorRef *error,
  76                            const uint8_t *der, uint8_t *der_end)
  77 {
  78     if (NULL == der_end) {
  79         SecCFDERCreateError(kSecDERErrorNullInput, CFSTR("null input"), NULL, error);
  80         return NULL;
  81     }
  82
  83     const CFIndex str_length = CFStringGetLength(string);
  84
  85     ptrdiff_t der_space = der_end - der;
  86     CFIndex bytes_used = 0;
  87     uint8_t *buffer = der_end - der_space;
  88     CFIndex converted = CFStringGetBytes(string, CFRangeMake(0, str_length), kCFStringEncodingUTF8, 0, false, buffer, der_space, &bytes_used);
  89     if (converted != str_length){
  90         SecCFDERCreateError(kSecDERErrorUnsupportedCFObject, CFSTR("String extraction failed"), NULL, error);
  91         return NULL;
  92     }
  93
  94     return SecCCDEREncodeHandleResult(ccder_encode_tl(CCDER_UTF8_STRING, bytes_used, der,
  95                                                       ccder_encode_body(bytes_used, buffer, der, der_end)),
  96                                       error);
  97
  98 }