AppleCSP/MiscCSPAlgs/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 BlockCrytpor and ssleay RC4 implementation
  21  * Written by Doug Mitchell 04/03/2001
  22  */
  23
  24 #include <openssl/rc4.h>
  25 #include "rc4Context.h"
  26
  27 RC4Context::~RC4Context()
  28 {
  29         memset(&rc4Key, 0, sizeof(RC4_KEY));
  30 }
  31
  32 /*
  33  * Standard CSPContext init, called from CSPFullPluginSession::init().
  34  * Reusable, e.g., query followed by en/decrypt.
  35  */
  36 void RC4Context::init(
  37         const Context &context,
  38         bool encrypting)
  39 {
  40         UInt32          keyLen;
  41         UInt8           *keyData        = NULL;
  42
  43         /* obtain key from context */
  44         symmetricKeyBits(context, CSSM_ALGID_RC4,
  45                 encrypting ? CSSM_KEYUSE_ENCRYPT : CSSM_KEYUSE_DECRYPT,
  46                 keyData, keyLen);
  47         if((keyLen < RC4_MIN_KEY_SIZE_BYTES) || (keyLen > RC4_MAX_KEY_SIZE_BYTES)) {
  48                 CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_KEY);
  49         }
  50
  51         /* All other context attributes ignored */
  52         /* init the low-level state */
  53         RC4_set_key(&rc4Key, keyLen, keyData);
  54 }
  55
  56 /*
  57  * All of these functions are called by CSPFullPluginSession.
  58  */
  59 void RC4Context::update(
  60         void                    *inp,
  61         size_t                  &inSize,                        // in/out
  62         void                    *outp,
  63         size_t                  &outSize)                       // in/out
  64 {
  65         RC4(&rc4Key, inSize, (unsigned char *)inp, (unsigned char *)outp);
  66         outSize = inSize;
  67 }
  68
  69 /* remainding functions are trivial for any stream cipher */
  70 void RC4Context::final(
  71         CssmData                &out)
  72 {
  73         out.length(0);
  74 }
  75
  76 size_t RC4Context::inputSize(
  77         size_t                  outSize)                        // input for given output size
  78 {
  79         return outSize;
  80 }
  81
  82 size_t RC4Context::outputSize(
  83         bool                    final = false,
  84         size_t                  inSize = 0)             // output for given input size
  85 {
  86         return inSize;
  87 }
  88
  89 void RC4Context::minimumProgress(
  90         size_t                  &in,
  91         size_t                  &out)                           // minimum progress chunks
  92 {
  93         in  = 1;
  94         out = 1;
  95 }