]> git.saurik.com Git - apple/security.git/blob - OSX/libsecurity_transform/lib/CEncryptDecrypt.c
Security-57337.20.44.tar.gz
[apple/security.git] / OSX / libsecurity_transform / lib / CEncryptDecrypt.c
1 /*
2 * Copyright (c) 2012 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 <CoreFoundation/CoreFoundation.h>
26 #include "corecrypto/ccsha1.h"
27 #include "corecrypto/ccrsa_priv.h"
28 #include "corecrypto/ccrng_system.h"
29 #include "corecrypto/ccn.h"
30 #include "stdio.h"
31 #include "misc.h"
32
33 // corecrypto headers don't like C++ (on a deaper level then extern "C" {} can fix
34 // so we need a C "shim" for all our corecrypto use.
35
36 CFDataRef oaep_padding_via_c(int desired_message_length, CFDataRef dataValue);
37 CFDataRef oaep_padding_via_c(int desired_message_length, CFDataRef dataValue)
38 {
39 cc_unit paddingBuffer[ccn_nof_size(desired_message_length)];
40 bzero(paddingBuffer, sizeof(cc_unit) * ccn_nof_size(desired_message_length)); // XXX needed??
41 static dispatch_once_t randomNumberGenneratorInitialzed;
42 static struct ccrng_system_state rng;
43 dispatch_once(&randomNumberGenneratorInitialzed, ^{
44 ccrng_system_init(&rng);
45 });
46
47 ccrsa_oaep_encode(ccsha1_di(),
48 (struct ccrng_state*)&rng,
49 sizeof(paddingBuffer), (cc_unit*)paddingBuffer,
50 CFDataGetLength(dataValue), CFDataGetBytePtr(dataValue));
51 ccn_swap(ccn_nof_size(sizeof(paddingBuffer)), (cc_unit*)paddingBuffer);
52
53 CFDataRef paddedValue = CFDataCreate(NULL, (UInt8*)paddingBuffer, desired_message_length);
54 return paddedValue ? paddedValue : (void*)GetNoMemoryErrorAndRetain();
55 }
56
57 CFDataRef oaep_unpadding_via_c(CFDataRef encodedMessage);
58 CFDataRef oaep_unpadding_via_c(CFDataRef encodedMessage)
59 {
60 size_t mlen = CFDataGetLength(encodedMessage);
61 cc_size n = ccn_nof_size(mlen);
62 cc_unit paddingBuffer[n];
63 UInt8 plainText[mlen];
64
65 ccn_read_uint(n, paddingBuffer, mlen, CFDataGetBytePtr(encodedMessage));
66 size_t plainTextLength = mlen;
67 int err = ccrsa_oaep_decode(ccsha1_di(), &plainTextLength, plainText, mlen, paddingBuffer);
68
69 if (err) {
70 // XXX should make a CFError or something.
71 return (void*)fancy_error(CFSTR("CoreCrypto"), err, CFSTR("OAEP decode error"));
72 }
73 CFDataRef result = CFDataCreate(NULL, (UInt8*)plainText, plainTextLength);
74 return result;
75 }