pdftops/SecurityHandler.h

   1 //========================================================================
   2 //
   3 // SecurityHandler.h
   4 //
   5 // Copyright 2004 Glyph & Cog, LLC
   6 //
   7 //========================================================================
   8
   9 #ifndef SECURITYHANDLER_H
  10 #define SECURITYHANDLER_H
  11
  12 #include <config.h>
  13
  14 #ifdef USE_GCC_PRAGMAS
  15 #pragma interface
  16 #endif
  17
  18 #include "gtypes.h"
  19 #include "Object.h"
  20
  21 class GString;
  22 class PDFDoc;
  23 struct XpdfSecurityHandler;
  24
  25 //------------------------------------------------------------------------
  26 // SecurityHandler
  27 //------------------------------------------------------------------------
  28
  29 class SecurityHandler {
  30 public:
  31
  32   static SecurityHandler *make(PDFDoc *docA, Object *encryptDictA);
  33
  34   SecurityHandler(PDFDoc *docA);
  35   virtual ~SecurityHandler();
  36
  37   // Check the document's encryption.  If the document is encrypted,
  38   // this will first try <ownerPassword> and <userPassword> (in
  39   // "batch" mode), and if those fail, it will attempt to request a
  40   // password from the user.  This is the high-level function that
  41   // calls the lower level functions for the specific security handler
  42   // (requesting a password three times, etc.).  Returns true if the
  43   // document can be opened (if it's unencrypted, or if a correct
  44   // password is obtained); false otherwise (encrypted and no correct
  45   // password).
  46   GBool checkEncryption(GString *ownerPassword,
  47                         GString *userPassword);
  48
  49   // Create authorization data for the specified owner and user
  50   // passwords.  If the security handler doesn't support "batch" mode,
  51   // this function should return NULL.
  52   virtual void *makeAuthData(GString *ownerPassword,
  53                              GString *userPassword) = 0;
  54
  55   // Construct authorization data, typically by prompting the user for
  56   // a password.  Returns an authorization data object, or NULL to
  57   // cancel.
  58   virtual void *getAuthData() = 0;
  59
  60   // Free the authorization data returned by makeAuthData or
  61   // getAuthData.
  62   virtual void freeAuthData(void *authData) = 0;
  63
  64   // Attempt to authorize the document, using the supplied
  65   // authorization data (which may be NULL).  Returns true if
  66   // successful (i.e., if at least the right to open the document was
  67   // granted).
  68   virtual GBool authorize(void *authData) = 0;
  69
  70   // Return the various authorization parameters.  These are only
  71   // valid after authorize has returned true.
  72   virtual int getPermissionFlags() = 0;
  73   virtual GBool getOwnerPasswordOk() = 0;
  74   virtual Guchar *getFileKey() = 0;
  75   virtual int getFileKeyLength() = 0;
  76   virtual int getEncVersion() = 0;
  77
  78 protected:
  79
  80   PDFDoc *doc;
  81 };
  82
  83 //------------------------------------------------------------------------
  84 // StandardSecurityHandler
  85 //------------------------------------------------------------------------
  86
  87 class StandardSecurityHandler: public SecurityHandler {
  88 public:
  89
  90   StandardSecurityHandler(PDFDoc *docA, Object *encryptDictA);
  91   virtual ~StandardSecurityHandler();
  92
  93   virtual void *makeAuthData(GString *ownerPassword,
  94                              GString *userPassword);
  95   virtual void *getAuthData();
  96   virtual void freeAuthData(void *authData);
  97   virtual GBool authorize(void *authData);
  98   virtual int getPermissionFlags() { return permFlags; }
  99   virtual GBool getOwnerPasswordOk() { return ownerPasswordOk; }
 100   virtual Guchar *getFileKey() { return fileKey; }
 101   virtual int getFileKeyLength() { return fileKeyLength; }
 102   virtual int getEncVersion() { return encVersion; }
 103
 104 private:
 105
 106   int permFlags;
 107   GBool ownerPasswordOk;
 108   Guchar fileKey[16];
 109   int fileKeyLength;
 110   int encVersion;
 111   int encRevision;
 112   GBool encryptMetadata;
 113
 114   GString *ownerKey, *userKey;
 115   GString *fileID;
 116   GBool ok;
 117 };
 118
 119 #ifdef ENABLE_PLUGINS
 120 //------------------------------------------------------------------------
 121 // ExternalSecurityHandler
 122 //------------------------------------------------------------------------
 123
 124 class ExternalSecurityHandler: public SecurityHandler {
 125 public:
 126
 127   ExternalSecurityHandler(PDFDoc *docA, Object *encryptDictA,
 128                           XpdfSecurityHandler *xshA);
 129   virtual ~ExternalSecurityHandler();
 130
 131   virtual void *makeAuthData(GString *ownerPassword,
 132                              GString *userPassword);
 133   virtual void *getAuthData();
 134   virtual void freeAuthData(void *authData);
 135   virtual GBool authorize(void *authData);
 136   virtual int getPermissionFlags() { return permFlags; }
 137   virtual GBool getOwnerPasswordOk() { return gFalse; }
 138   virtual Guchar *getFileKey() { return fileKey; }
 139   virtual int getFileKeyLength() { return fileKeyLength; }
 140   virtual int getEncVersion() { return encVersion; }
 141
 142 private:
 143
 144   Object encryptDict;
 145   XpdfSecurityHandler *xsh;
 146   void *docData;
 147   int permFlags;
 148   Guchar fileKey[16];
 149   int fileKeyLength;
 150   int encVersion;
 151   GBool ok;
 152 };
 153 #endif // ENABLE_PLUGINS
 154
 155 #endif