libsecurity_apple_csp/lib/rc4Context.cpp

   1 /*
   2  * Copyright (c) 2000-2001 Apple Computer, 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  * Written by Doug Mitchell 04/03/2001
  22  */
  23
  24 #include "rc4Context.h"
  25
  26 RC4Context::~RC4Context()
  27 {
  28     if (rc4Key != NULL) {
  29         CCCryptorRelease(rc4Key);
  30     }
  31     rc4Key = NULL;
  32 }
  33
  34 /*
  35  * Standard CSPContext init, called from CSPFullPluginSession::init().
  36  * Reusable, e.g., query followed by en/decrypt.
  37  */
  38 void RC4Context::init(
  39         const Context &context,
  40         bool encrypting)
  41 {
  42         CSSM_SIZE       keyLen;
  43         uint8           *keyData        = NULL;
  44
  45         /* obtain key from context */
  46         symmetricKeyBits(context, session(), CSSM_ALGID_RC4,
  47                 encrypting ? CSSM_KEYUSE_ENCRYPT : CSSM_KEYUSE_DECRYPT,
  48                 keyData, keyLen);
  49         if((keyLen < kCCKeySizeMinRC4) || (keyLen > kCCKeySizeMaxRC4)) {
  50                 CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_KEY);
  51         }
  52
  53         /* All other context attributes ignored */
  54         /* init the low-level state */
  55     (void) CCCryptorCreateWithMode(0, kCCModeRC4, kCCAlgorithmRC4, ccDefaultPadding, NULL, keyData, keyLen, NULL, 0, 0, 0, &rc4Key);
  56
  57 }
  58
  59 /*
  60  * All of these functions are called by CSPFullPluginSession.
  61  */
  62 void RC4Context::update(
  63         void                    *inp,
  64         size_t                  &inSize,                        // in/out
  65         void                    *outp,
  66         size_t                  &outSize)                       // in/out
  67 {
  68     (void) CCCryptorUpdate(rc4Key, inp, inSize, outp, inSize, &outSize);
  69 }
  70
  71 /* remainding functions are trivial for any stream cipher */
  72 void RC4Context::final(
  73         CssmData                &out)
  74 {
  75         out.length(0);
  76 }
  77
  78 size_t RC4Context::inputSize(
  79         size_t                  outSize)                        // input for given output size
  80 {
  81         return outSize;
  82 }
  83
  84 size_t RC4Context::outputSize(
  85         bool                    final /*= false*/,
  86         size_t                  inSize /*= 0*/)         // output for given input size
  87 {
  88         return inSize;
  89 }
  90
  91 void RC4Context::minimumProgress(
  92         size_t                  &in,
  93         size_t                  &out)                           // minimum progress chunks
  94 {
  95         in  = 1;
  96         out = 1;
  97 }