Security/libsecurity_apple_csp/lib/rc2Context.cpp

   1 /*
   2  * Copyright (c) 2000-2001,2011-2012,2014 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  * rc2Context.cpp - glue between BlockCrytpor and ssleay RC2 implementation
  21  */
  22
  23 #include <openssl/rc2.h>
  24 #include <misc/rc2_locl.h>
  25 #include "rc2Context.h"
  26
  27 RC2Context::~RC2Context()
  28 {
  29         memset(&rc2Key, 0, sizeof(RC2_KEY));
  30 }
  31
  32 /*
  33  * Standard CSPContext init, called from CSPFullPluginSession::init().
  34  * Reusable, e.g., query followed by en/decrypt.
  35  */
  36 void RC2Context::init(
  37         const Context &context,
  38         bool encrypting)
  39 {
  40         CSSM_SIZE       keyLen;
  41         uint8           *keyData        = NULL;
  42         uint32          effectiveBits;
  43
  44         /* obtain key from context */
  45         symmetricKeyBits(context, session(), CSSM_ALGID_RC2,
  46                 encrypting ? CSSM_KEYUSE_ENCRYPT : CSSM_KEYUSE_DECRYPT,
  47                 keyData, keyLen);
  48         if((keyLen < RC2_MIN_KEY_SIZE_BYTES) || (keyLen > RC2_MAX_KEY_SIZE_BYTES)) {
  49                 CssmError::throwMe(CSSMERR_CSP_INVALID_ATTR_KEY);
  50         }
  51
  52         /*
  53          * Optional effective key size in bits - either from Context,
  54          * or the key
  55          */
  56         effectiveBits = context.getInt(CSSM_ATTRIBUTE_EFFECTIVE_BITS);
  57         if(effectiveBits == 0) {
  58                 CssmKey &key = context.get<CssmKey>(CSSM_ATTRIBUTE_KEY,
  59                         CSSMERR_CSP_MISSING_ATTR_KEY);
  60                 effectiveBits = key.KeyHeader.LogicalKeySizeInBits;
  61         }
  62
  63         /* init the low-level state */
  64         RC2_set_key(&rc2Key, (int)keyLen, keyData, effectiveBits);
  65
  66         /* Finally, have BlockCryptor do its setup */
  67         setup(RC2_BLOCK_SIZE_BYTES, context);
  68 }
  69
  70 /*
  71  * Functions called by BlockCryptor
  72  */
  73 void RC2Context::encryptBlock(
  74         const void              *plainText,                     // length implied (one block)
  75         size_t                  plainTextLen,
  76         void                    *cipherText,
  77         size_t                  &cipherTextLen,         // in/out, throws on overflow
  78         bool                    final)                          // ignored
  79 {
  80         if(plainTextLen != RC2_BLOCK_SIZE_BYTES) {
  81                 CssmError::throwMe(CSSMERR_CSP_INPUT_LENGTH_ERROR);
  82         }
  83         if(cipherTextLen < RC2_BLOCK_SIZE_BYTES) {
  84                 CssmError::throwMe(CSSMERR_CSP_OUTPUT_LENGTH_ERROR);
  85         }
  86
  87         /*
  88          * Low-level code operates on array of unsigned 32-bit integers
  89          */
  90         RC2_INT d[2];
  91         RC2_INT l;
  92         const unsigned char *pt = (const unsigned char *)plainText;
  93         c2l(pt, l); d[0]=l;
  94         c2l(pt, l); d[1]=l;
  95         RC2_encrypt(d, &rc2Key);
  96         unsigned char *ct = (unsigned char *)cipherText;
  97         l=d[0]; l2c(l, ct);
  98         l=d[1]; l2c(l, ct);
  99         cipherTextLen = RC2_BLOCK_SIZE_BYTES;
 100 }
 101
 102 void RC2Context::decryptBlock(
 103         const void              *cipherText,            // length implied (one block)
 104         size_t                  cipherTextLen,
 105         void                    *plainText,
 106         size_t                  &plainTextLen,          // in/out, throws on overflow
 107         bool                    final)                          // ignored
 108 {
 109         if(plainTextLen < RC2_BLOCK_SIZE_BYTES) {
 110                 CssmError::throwMe(CSSMERR_CSP_OUTPUT_LENGTH_ERROR);
 111         }
 112         /*
 113          * Low-level code operates on array of unsigned 32-bit integers
 114          */
 115         RC2_INT d[2];
 116         RC2_INT l;
 117         const unsigned char *ct = (const unsigned char *)cipherText;
 118         c2l(ct, l); d[0]=l;
 119         c2l(ct, l); d[1]=l;
 120         RC2_decrypt(d, &rc2Key);
 121         unsigned char *pt = (unsigned char *)plainText;
 122         l=d[0]; l2c(l, pt);
 123         l=d[1]; l2c(l, pt);
 124         plainTextLen = RC2_BLOCK_SIZE_BYTES;
 125 }
 126