libsecurity_codesigning/lib/reqreader.h

   1 /*
   2  * Copyright (c) 2007 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 //
  25 // reqreader - Requirement language (exprOp) reader/scanner
  26 //
  27 #ifndef _H_REQREADER
  28 #define _H_REQREADER
  29
  30 #include <security_codesigning/requirement.h>
  31 #include <Security/SecCertificate.h>
  32
  33 namespace Security {
  34 namespace CodeSigning {
  35
  36
  37 //
  38 // The Reader class provides structured access to a opExpr-type code requirement.
  39 //
  40 class Requirement::Reader {
  41 public:
  42         Reader(const Requirement *req);
  43
  44         const Requirement *requirement() const { return mReq; }
  45
  46         template <class T> T get();
  47         void getData(const void *&data, size_t &length);
  48
  49         std::string getString();
  50         const unsigned char *getHash();
  51         const unsigned char *getSHA1();
  52
  53         template <class T> void getData(T *&data, size_t &length)
  54         { return getData(reinterpret_cast<const void *&>(data), length); }
  55
  56 protected:
  57         void checkSize(size_t length)
  58         {
  59                 if (mPC + length < mPC || mPC + length > mReq->length())
  60                         MacOSError::throwMe(errSecCSReqInvalid);
  61         }
  62
  63         void skip(size_t length);
  64
  65         Offset pc() const { return mPC; }
  66         bool atEnd() const { return mPC >= mReq->length(); }
  67
  68 private:
  69         const Requirement * const mReq;
  70         Offset mPC;
  71 };
  72
  73 template <class T>
  74 T Requirement::Reader::get()
  75 {
  76         checkSize(sizeof(T));
  77         const Endian<const T> *value = mReq->at<Endian<const T> >(mPC);
  78         mPC += sizeof(T);
  79         return *value;
  80 }
  81
  82
  83 }       // CodeSigning
  84 }       // Security
  85
  86 #endif //_H_REQREADER