OSX/libsecurity_apple_csp/lib/rc4Context.cpp

   1 /*
   2  * Copyright (c) 2000-2001,2011,2014 Apple Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please obtain
   7  * a copy of the License at http://www.apple.com/publicsource and read it before
   8  * using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
  12  * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
  13  * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
  14  * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
  15  * specific language governing rights and limitations under the License.
  16  */
  17
  18
  19 /*
  20  * rc4Context.cpp - glue between AppleCSPContext and ssleay RC4 implementation
  21  */
  22
  23 #include "rc4Context.h"
  24
  25 RC4Context::~RC4Context()
  26 {
  27     if (rc4Key != NULL) {
  28         CCCryptorRelease(rc4Key);
  29     }
  30     rc4Key = NULL;
  31 }
  32
  33 /*
  34  * Standard CSPContext init, called from CSPFullPluginSession::init().
  35  * Reusable, e.g., query followed by en/decrypt.
  36  */
  37 void RC4Context::init(
  38         const Context &context,
  39         bool encrypting)
  40 {
  41         CSSM_SIZE       keyLen;
  42         uint8           *keyData        = NULL;
  43
  44         /* obtain key from context */
  45         symmetricKeyBits(context, session(), CSSM_ALGID_RC4,
  46                 encrypting ? CSSM_KEYUSE_ENCRYPT : CSSM_KEYUSE_DECRYPT,
  47                 keyData, keyLen);
  48         if((keyLen < kCCKeySizeMinRC4) || (keyLen > kCCKeySizeMaxRC4)) {
  49                 CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_KEY);
  50         }
  51
  52         /* All other context attributes ignored */
  53         /* init the low-level state */
  54     (void) CCCryptorCreateWithMode(0, kCCModeRC4, kCCAlgorithmRC4, ccDefaultPadding, NULL, keyData, keyLen, NULL, 0, 0, 0, &rc4Key);
  55
  56 }
  57
  58 /*
  59  * All of these functions are called by CSPFullPluginSession.
  60  */
  61 void RC4Context::update(
  62         void                    *inp,
  63         size_t                  &inSize,                        // in/out
  64         void                    *outp,
  65         size_t                  &outSize)                       // in/out
  66 {
  67     (void) CCCryptorUpdate(rc4Key, inp, inSize, outp, inSize, &outSize);
  68 }
  69
  70 /* remainding functions are trivial for any stream cipher */
  71 void RC4Context::final(
  72         CssmData                &out)
  73 {
  74         out.length(0);
  75 }
  76
  77 size_t RC4Context::inputSize(
  78         size_t                  outSize)                        // input for given output size
  79 {
  80         return outSize;
  81 }
  82
  83 size_t RC4Context::outputSize(
  84         bool                    final /*= false*/,
  85         size_t                  inSize /*= 0*/)         // output for given input size
  86 {
  87         return inSize;
  88 }
  89
  90 void RC4Context::minimumProgress(
  91         size_t                  &in,
  92         size_t                  &out)                           // minimum progress chunks
  93 {
  94         in  = 1;
  95         out = 1;
  96 }