1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
// Copyright 2016 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
#ifndef CORE_FPDFAPI_PARSER_CPDF_PARSER_H_
#define CORE_FPDFAPI_PARSER_CPDF_PARSER_H_
#include <limits>
#include <map>
#include <memory>
#include <set>
#include <vector>
#include "core/fxcrt/cfx_unowned_ptr.h"
#include "core/fxcrt/fx_basic.h"
class CPDF_Array;
class CPDF_CryptoHandler;
class CPDF_Dictionary;
class CPDF_Document;
class CPDF_IndirectObjectHolder;
class CPDF_LinearizedHeader;
class CPDF_Object;
class CPDF_SecurityHandler;
class CPDF_StreamAcc;
class CPDF_SyntaxParser;
class IFX_SeekableReadStream;
class CPDF_Parser {
public:
enum Error {
SUCCESS = 0,
FILE_ERROR,
FORMAT_ERROR,
PASSWORD_ERROR,
HANDLER_ERROR
};
enum class ObjectType : uint8_t {
kFree = 0x00,
kNotCompressed = 0x01,
kCompressed = 0x02,
kNull = 0xFF,
};
// A limit on the maximum object number in the xref table. Theoretical limits
// are higher, but this may be large enough in practice.
static const uint32_t kMaxObjectNumber = 1048576;
static const size_t kInvalidPos = std::numeric_limits<size_t>::max();
CPDF_Parser();
~CPDF_Parser();
Error StartParse(const CFX_RetainPtr<IFX_SeekableReadStream>& pFile,
CPDF_Document* pDocument);
Error StartLinearizedParse(const CFX_RetainPtr<IFX_SeekableReadStream>& pFile,
CPDF_Document* pDocument);
void SetPassword(const char* password) { m_Password = password; }
CFX_ByteString GetPassword() { return m_Password; }
CPDF_Dictionary* GetTrailer() const;
FX_FILESIZE GetLastXRefOffset() const { return m_LastXRefOffset; }
uint32_t GetPermissions() const;
uint32_t GetRootObjNum();
uint32_t GetInfoObjNum();
CPDF_Array* GetIDArray();
CPDF_Dictionary* GetEncryptDict() const { return m_pEncryptDict.Get(); }
std::unique_ptr<CPDF_Object> ParseIndirectObject(
CPDF_IndirectObjectHolder* pObjList,
uint32_t objnum);
uint32_t GetLastObjNum() const;
bool IsValidObjectNumber(uint32_t objnum) const;
FX_FILESIZE GetObjectPositionOrZero(uint32_t objnum) const;
ObjectType GetObjectType(uint32_t objnum) const;
uint16_t GetObjectGenNum(uint32_t objnum) const;
bool IsObjectFreeOrNull(uint32_t objnum) const;
CFX_RetainPtr<CPDF_CryptoHandler> GetCryptoHandler() const;
CFX_RetainPtr<IFX_SeekableReadStream> GetFileAccess() const;
FX_FILESIZE GetObjectOffset(uint32_t objnum) const;
int GetFileVersion() const { return m_FileVersion; }
bool IsXRefStream() const { return m_bXRefStream; }
std::unique_ptr<CPDF_Object> ParseIndirectObjectAt(
CPDF_IndirectObjectHolder* pObjList,
FX_FILESIZE pos,
uint32_t objnum);
std::unique_ptr<CPDF_Object> ParseIndirectObjectAtByStrict(
CPDF_IndirectObjectHolder* pObjList,
FX_FILESIZE pos,
uint32_t objnum,
FX_FILESIZE* pResultPos);
uint32_t GetFirstPageNo() const;
protected:
struct ObjectInfo {
ObjectInfo() : pos(0), type(ObjectType::kFree), gennum(0) {}
// if type is ObjectType::kCompressed the archive_obj_num should be used.
// if type is ObjectType::kNotCompressed the pos should be used.
// In other cases its are unused.
union {
FX_FILESIZE pos;
FX_FILESIZE archive_obj_num;
};
ObjectType type;
uint16_t gennum;
};
std::unique_ptr<CPDF_SyntaxParser> m_pSyntax;
std::map<uint32_t, ObjectInfo> m_ObjectInfo;
bool LoadCrossRefV4(FX_FILESIZE pos, FX_FILESIZE streampos, bool bSkip);
bool RebuildCrossRef();
private:
friend class CPDF_DataAvail;
class TrailerData;
enum class ParserState {
kDefault,
kComment,
kWhitespace,
kString,
kHexString,
kEscapedString,
kXref,
kObjNum,
kPostObjNum,
kGenNum,
kPostGenNum,
kTrailer,
kBeginObj,
kEndObj
};
struct CrossRefObjData {
uint32_t obj_num = 0;
ObjectInfo info;
};
Error StartParseInternal(CPDF_Document* pDocument);
CPDF_Object* ParseDirect(CPDF_Object* pObj);
bool LoadAllCrossRefV4(FX_FILESIZE pos);
bool LoadAllCrossRefV5(FX_FILESIZE pos);
bool LoadCrossRefV5(FX_FILESIZE* pos, bool bMainXRef);
std::unique_ptr<CPDF_Dictionary> LoadTrailerV4();
Error SetEncryptHandler();
void ReleaseEncryptHandler();
bool LoadLinearizedAllCrossRefV4(FX_FILESIZE pos, uint32_t dwObjCount);
bool LoadLinearizedCrossRefV4(FX_FILESIZE pos, uint32_t dwObjCount);
bool LoadLinearizedAllCrossRefV5(FX_FILESIZE pos);
Error LoadLinearizedMainXRefTable();
CFX_RetainPtr<CPDF_StreamAcc> GetObjectStream(uint32_t number);
bool ParseLinearizedHeader();
void SetEncryptDictionary(CPDF_Dictionary* pDict);
void ShrinkObjectMap(uint32_t size);
// A simple check whether the cross reference table matches with
// the objects.
bool VerifyCrossRefV4();
// If out_objects is null, the parser position will be moved to end subsection
// without additional validation.
bool ParseAndAppendCrossRefSubsectionData(
uint32_t start_objnum,
uint32_t count,
std::vector<CrossRefObjData>* out_objects);
bool ParseCrossRefV4(std::vector<CrossRefObjData>* out_objects);
void MergeCrossRefObjectsData(const std::vector<CrossRefObjData>& objects);
std::unique_ptr<CPDF_Object> ParseIndirectObjectAtInternal(
CPDF_IndirectObjectHolder* pObjList,
FX_FILESIZE pos,
uint32_t objnum,
bool strict_parse,
FX_FILESIZE* pResultPos);
bool InitSyntaxParser(
const CFX_RetainPtr<IFX_SeekableReadStream>& file_access);
bool ParseFileVersion();
CFX_UnownedPtr<CPDF_Document> m_pDocument;
bool m_bHasParsed;
bool m_bXRefStream;
int m_FileVersion;
CFX_UnownedPtr<CPDF_Dictionary> m_pEncryptDict;
FX_FILESIZE m_LastXRefOffset;
std::unique_ptr<CPDF_SecurityHandler> m_pSecurityHandler;
CFX_ByteString m_Password;
std::unique_ptr<TrailerData> m_TrailerData;
std::unique_ptr<CPDF_LinearizedHeader> m_pLinearized;
uint32_t m_dwLinearizedFirstPageXRefStartObjNum;
// A map of object numbers to indirect streams.
std::map<uint32_t, CFX_RetainPtr<CPDF_StreamAcc>> m_ObjectStreamMap;
// Mapping of object numbers to offsets. The offsets are relative to the first
// object in the stream.
using StreamObjectCache = std::map<uint32_t, uint32_t>;
// Mapping of streams to their object caches. This is valid as long as the
// streams in |m_ObjectStreamMap| are valid.
std::map<CFX_RetainPtr<CPDF_StreamAcc>, StreamObjectCache> m_ObjCache;
// All indirect object numbers that are being parsed.
std::set<uint32_t> m_ParsingObjNums;
};
#endif // CORE_FPDFAPI_PARSER_CPDF_PARSER_H_
|
