Security-57031.1.35.tar.gz

[apple/security.git] / Security / libsecurity_apple_csp / lib / castContext.h

diff --git a/Security/libsecurity_apple_csp/lib/castContext.h b/Security/libsecurity_apple_csp/lib/castContext.h
new file mode 100644 (file)
index 0000000..928c19a
--- /dev/null
+++ b/Security/libsecurity_apple_csp/lib/castContext.h
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2000-2001,2011,2013-2014 Apple Inc. All Rights Reserved.
+ * 
+ * The contents of this file constitute Original Code as defined in and are
+ * subject to the Apple Public Source License Version 1.2 (the 'License').
+ * You may not use this file except in compliance with the License. Please obtain
+ * a copy of the License at http://www.apple.com/publicsource and read it before
+ * using this file.
+ * 
+ * This Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS
+ * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT
+ * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+ * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the
+ * specific language governing rights and limitations under the License.
+ */
+
+
+/*
+ * castContext.h - glue between BlockCrytpor and ssleay CAST-128 (CAST5)
+ *                              implementation
+ *
+ *
+ * Here's what RFC 2144 has to say about CAST128 and CAST5 nomenclature:
+ *
+ *    In order to avoid confusion when variable keysize operation is 
+ *    used, the name CAST-128 is to be considered synonymous with the 
+ *    name CAST5; this allows a keysize to be appended without ambiguity.  
+ *    Thus, for example, CAST-128 with a 40-bit key is to be referred to 
+ *    as CAST5-40; where a 128-bit key is explicitly intended, the 
+ *    name CAST5-128 should be used. 
+ *
+ * This module implements a variable key length, from 40 bits to 128 bits,
+ * and can thus be said to implement both CAST-128 and CAST5.
+ */
+ 
+#ifndef _CAST_CONTEXT_H_
+#define _CAST_CONTEXT_H_
+
+#include "AppleCSPContext.h"
+#include "BlockCryptor.h"
+#include <CommonCrypto/CommonCryptor.h>
+#include <CommonCrypto/CommonCryptorSPI.h>
+
+class CastContext : public BlockCryptor {
+public:
+       CastContext(AppleCSPSession &session);
+       virtual ~CastContext();
+       
+       // called by CSPFullPluginSession
+       void init(const Context &context, bool encoding = true);
+
+       // As an optimization, we allow reuse of a modified context. 
+       // The main thing we avoid is a redundant key scheduling. We 
+       // save the current raw keys bits in mRawKey and compare on 
+       // re-init.
+       bool changed(const Context &context)     { return true; }
+
+       // called by BlockCryptor
+       void encryptBlock(
+               const void              *plainText,             // length implied (one block)
+               size_t                  plainTextLen,
+               void                    *cipherText,    
+               size_t                  &cipherTextLen, // in/out, throws on overflow
+               bool                    final);
+       void decryptBlock(
+               const void              *cipherText,    // length implied (one cipher block)
+               size_t                  cipherTextLen,
+               void                    *plainText,     
+               size_t                  &plainTextLen,  // in/out, throws on overflow
+               bool                    final);
+       
+private:
+       void deleteKey();
+
+       /* scheduled key */
+    CCCryptorRef       mCastKey;               
+
+       bool                            mInitFlag;                      // for easy reuse
+
+       /* 
+        * Raw key bits saved here and checked on re-init to avoid 
+        * extra key schedule 
+        */
+       uint8                           mRawKey[kCCKeySizeMaxCAST];
+       uint32                          mRawKeySize;
+
+       
+};     /* CastContext */
+
+#endif //_CAST_CONTEXT_H_