libsecurity_ssl/lib/symCipher.c

   1 /*
   2  * Copyright (c) 1999-2001,2005-2008,2010-2012 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  * symCipher.c - CDSA-based symmetric cipher module
  26  */
  27
  28 #include "sslContext.h"
  29 #include "cryptType.h"
  30 #include "sslDebug.h"
  31 #include "sslMemory.h"
  32 #include <CommonCrypto/CommonCryptor.h>
  33 #include "symCipher.h"
  34
  35 /*
  36  * CommonCrypto-based symmetric cipher callouts
  37  */
  38 OSStatus CCSymmInit(
  39         uint8_t *key,
  40         uint8_t* iv,
  41         CipherContext *cipherCtx,
  42         SSLContext *ctx)
  43 {
  44         /*
  45          * Cook up a CCCryptorRef. Assumes:
  46          *              cipherCtx->symCipher.keyAlg
  47          *              cipherCtx->encrypting
  48          *              key (raw key bytes)
  49          *              iv (raw bytes)
  50          * On successful exit:
  51          *              Resulting CCCryptorRef --> cipherCtx->cryptorRef
  52          */
  53         CCCryptorStatus ccrtn;
  54         CCOperation op = cipherCtx->encrypting ? kCCEncrypt : kCCDecrypt;
  55
  56         if(cipherCtx->cryptorRef) {
  57                 CCCryptorRelease(cipherCtx->cryptorRef);
  58                 cipherCtx->cryptorRef = NULL;
  59         }
  60
  61         ccrtn = CCCryptorCreate(op, cipherCtx->symCipher->keyAlg,
  62                 0,              /* options - no padding, default CBC */
  63                 key, cipherCtx->symCipher->keySize,
  64                 iv,
  65                 &cipherCtx->cryptorRef);
  66         if(ccrtn) {
  67                 sslErrorLog("CCCryptorCreate returned %d\n", (int)ccrtn);
  68                 return internalComponentErr;
  69         }
  70         return noErr;
  71 }
  72
  73 /* same for en/decrypt */
  74 OSStatus CCSymmEncryptDecrypt(
  75         const uint8_t *src,
  76         uint8_t *dest,
  77         size_t len,
  78         CipherContext *cipherCtx,
  79         SSLContext *ctx)
  80 {
  81         CCCryptorStatus ccrtn;
  82
  83         ASSERT(cipherCtx != NULL);
  84         ASSERT(cipherCtx->cryptorRef != NULL);
  85         if(cipherCtx->cryptorRef == NULL) {
  86                 sslErrorLog("CCSymmEncryptDecrypt: NULL cryptorRef\n");
  87                 return internalComponentErr;
  88         }
  89     size_t data_moved;
  90         ccrtn = CCCryptorUpdate(cipherCtx->cryptorRef, src, len,
  91                 dest, len, &data_moved);
  92     assert(data_moved == len);
  93         #if SSL_DEBUG
  94         if(ccrtn) {
  95                 sslErrorLog("CCSymmEncryptDecrypt: returned %d\n", (int)ccrtn);
  96                 return internalComponentErr;
  97         }
  98         #endif
  99         return noErr;
 100 }
 101
 102 OSStatus CCSymmFinish(
 103         CipherContext *cipherCtx,
 104         SSLContext *ctx)
 105 {
 106         if(cipherCtx->cryptorRef) {
 107                 CCCryptorRelease(cipherCtx->cryptorRef);
 108                 cipherCtx->cryptorRef = NULL;
 109         }
 110         return noErr;
 111 }
 112