fpdfsdk/fpdf_attachment.cpp - platform/external/pdfium - Gitiles

 // Copyright 2017 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.

 #include "public/fpdf_attachment.h"

 #include <memory>
 #include <utility>

 #include "constants/stream_dict_common.h"
 #include "core/fdrm/fx_crypt.h"
 #include "core/fpdfapi/parser/cpdf_array.h"
 #include "core/fpdfapi/parser/cpdf_dictionary.h"
 #include "core/fpdfapi/parser/cpdf_document.h"
 #include "core/fpdfapi/parser/cpdf_name.h"
 #include "core/fpdfapi/parser/cpdf_number.h"
 #include "core/fpdfapi/parser/cpdf_reference.h"
 #include "core/fpdfapi/parser/cpdf_stream.h"
 #include "core/fpdfapi/parser/cpdf_string.h"
 #include "core/fpdfapi/parser/fpdf_parser_decode.h"
 #include "core/fpdfdoc/cpdf_filespec.h"
 #include "core/fpdfdoc/cpdf_nametree.h"
 #include "core/fxcrt/cfx_datetime.h"
 #include "core/fxcrt/fx_extension.h"
 #include "core/fxcrt/fx_memory_wrappers.h"
 #include "fpdfsdk/cpdfsdk_helpers.h"
 #include "third_party/base/ptr_util.h"

 namespace {

 constexpr char kChecksumKey[] = "CheckSum";

 ByteString CFXByteStringHexDecode(const ByteString& bsHex) {
   std::unique_ptr<uint8_t, FxFreeDeleter> result;
   uint32_t size = 0;
   HexDecode(bsHex.raw_span(), &result, &size);
   return ByteString(result.get(), size);
 }

 ByteString GenerateMD5Base16(const void* contents, const unsigned long len) {
   uint8_t digest[16];
   CRYPT_MD5Generate({static_cast<const uint8_t*>(contents), len}, digest);
   char buf[32];
   for (int i = 0; i < 16; ++i)
     FXSYS_IntToTwoHexChars(digest[i], &buf[i * 2]);

   return ByteString(buf, 32);
 }

 }  // namespace

 FPDF_EXPORT int FPDF_CALLCONV
 FPDFDoc_GetAttachmentCount(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc)
     return 0;

   return CPDF_NameTree(pDoc, "EmbeddedFiles").GetCount();
 }

 FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
 FPDFDoc_AddAttachment(FPDF_DOCUMENT document, FPDF_WIDESTRING name) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc)
     return nullptr;

   CPDF_Dictionary* pRoot = pDoc->GetRoot();
   if (!pRoot)
     return nullptr;

   WideString wsName = WideStringFromFPDFWideString(name);
   if (wsName.IsEmpty())
     return nullptr;

   // Retrieve the document's Names dictionary; create it if missing.
   CPDF_Dictionary* pNames = pRoot->GetDictFor("Names");
   if (!pNames) {
     pNames = pDoc->NewIndirect<CPDF_Dictionary>();
     pRoot->SetNewFor<CPDF_Reference>("Names", pDoc, pNames->GetObjNum());
   }

   // Create the EmbeddedFiles dictionary if missing.
   if (!pNames->GetDictFor("EmbeddedFiles")) {
     CPDF_Dictionary* pFiles = pDoc->NewIndirect<CPDF_Dictionary>();
     pFiles->SetNewFor<CPDF_Array>("Names");
     pNames->SetNewFor<CPDF_Reference>("EmbeddedFiles", pDoc,
                                       pFiles->GetObjNum());
   }

   // Set up the basic entries in the filespec dictionary.
   CPDF_Dictionary* pFile = pDoc->NewIndirect<CPDF_Dictionary>();
   pFile->SetNewFor<CPDF_Name>("Type", "Filespec");
   pFile->SetNewFor<CPDF_String>("UF", wsName);
   pFile->SetNewFor<CPDF_String>(pdfium::stream::kF, wsName);

   // Add the new attachment name and filespec into the document's EmbeddedFiles.
   CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
   if (!nameTree.AddValueAndName(pFile->MakeReference(pDoc), wsName)) {
     return nullptr;
   }

   return FPDFAttachmentFromCPDFObject(pFile);
 }

 FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
 FPDFDoc_GetAttachment(FPDF_DOCUMENT document, int index) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc || index < 0)
     return nullptr;

   CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
   if (static_cast<size_t>(index) >= nameTree.GetCount())
     return nullptr;

   WideString csName;
   return FPDFAttachmentFromCPDFObject(
       nameTree.LookupValueAndName(index, &csName));
 }

 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFDoc_DeleteAttachment(FPDF_DOCUMENT document, int index) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc || index < 0)
     return false;

   CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
   if (static_cast<size_t>(index) >= nameTree.GetCount())
     return false;

   return nameTree.DeleteValueAndName(index);
 }

 FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetName(FPDF_ATTACHMENT attachment,
                        FPDF_WCHAR* buffer,
                        unsigned long buflen) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return 0;

   return Utf16EncodeMaybeCopyAndReturnLength(CPDF_FileSpec(pFile).GetFileName(),
                                              buffer, buflen);
 }

 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAttachment_HasKey(FPDF_ATTACHMENT attachment, FPDF_BYTESTRING key) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return 0;

   CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
   return pParamsDict ? pParamsDict->KeyExist(key) : 0;
 }

 FPDF_EXPORT FPDF_OBJECT_TYPE FPDF_CALLCONV
 FPDFAttachment_GetValueType(FPDF_ATTACHMENT attachment, FPDF_BYTESTRING key) {
   if (!FPDFAttachment_HasKey(attachment, key))
     return FPDF_OBJECT_UNKNOWN;

   CPDF_FileSpec spec(CPDFObjectFromFPDFAttachment(attachment));
   CPDF_Object* pObj = spec.GetParamsDict()->GetObjectFor(key);
   return pObj ? pObj->GetType() : FPDF_OBJECT_UNKNOWN;
 }

 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAttachment_SetStringValue(FPDF_ATTACHMENT attachment,
                               FPDF_BYTESTRING key,
                               FPDF_WIDESTRING value) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return false;

   CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
   if (!pParamsDict)
     return false;

   ByteString bsKey = key;
   ByteString bsValue = ByteStringFromFPDFWideString(value);
   bool bEncodedAsHex = bsKey == kChecksumKey;
   if (bEncodedAsHex)
     bsValue = CFXByteStringHexDecode(bsValue);

   pParamsDict->SetNewFor<CPDF_String>(bsKey, bsValue, bEncodedAsHex);
   return true;
 }

 FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetStringValue(FPDF_ATTACHMENT attachment,
                               FPDF_BYTESTRING key,
                               FPDF_WCHAR* buffer,
                               unsigned long buflen) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return 0;

   CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
   if (!pParamsDict)
     return 0;

   ByteString bsKey = key;
   WideString value = pParamsDict->GetUnicodeTextFor(bsKey);
   if (bsKey == kChecksumKey && !value.IsEmpty()) {
     CPDF_String* stringValue = pParamsDict->GetObjectFor(bsKey)->AsString();
     if (stringValue->IsHex()) {
       ByteString encoded = PDF_EncodeString(stringValue->GetString(), true);
       value = pdfium::MakeRetain<CPDF_String>(nullptr, encoded, false)
                   ->GetUnicodeText();
     }
   }

   return Utf16EncodeMaybeCopyAndReturnLength(value, buffer, buflen);
 }

 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFAttachment_SetFile(FPDF_ATTACHMENT attachment,
                        FPDF_DOCUMENT document,
                        const void* contents,
                        const unsigned long len) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pFile || !pFile->IsDictionary() || !pDoc || len > INT_MAX)
     return false;

   // An empty content must have a zero length.
   if (!contents && len != 0)
     return false;

   // Create a dictionary for the new embedded file stream.
   auto pFileStreamDict = pdfium::MakeRetain<CPDF_Dictionary>();
   CPDF_Dictionary* pParamsDict =
       pFileStreamDict->SetNewFor<CPDF_Dictionary>("Params");

   // Set the size of the new file in the dictionary.
   pFileStreamDict->SetNewFor<CPDF_Number>(pdfium::stream::kDL,
                                           static_cast<int>(len));
   pParamsDict->SetNewFor<CPDF_Number>("Size", static_cast<int>(len));

   // Set the creation date of the new attachment in the dictionary.
   CFX_DateTime dateTime = CFX_DateTime::Now();
   pParamsDict->SetNewFor<CPDF_String>(
       "CreationDate",
       ByteString::Format("D:%d%02d%02d%02d%02d%02d", dateTime.GetYear(),
                          dateTime.GetMonth(), dateTime.GetDay(),
                          dateTime.GetHour(), dateTime.GetMinute(),
                          dateTime.GetSecond()),
       false);

   // Set the checksum of the new attachment in the dictionary.
   pParamsDict->SetNewFor<CPDF_String>(
       kChecksumKey, CFXByteStringHexDecode(GenerateMD5Base16(contents, len)),
       true);

   // Create the file stream and have the filespec dictionary link to it.
   std::unique_ptr<uint8_t, FxFreeDeleter> stream(FX_Alloc(uint8_t, len));
   memcpy(stream.get(), contents, len);
   CPDF_Stream* pFileStream = pDoc->NewIndirect<CPDF_Stream>(
       std::move(stream), len, std::move(pFileStreamDict));
   CPDF_Dictionary* pEFDict =
       pFile->AsDictionary()->SetNewFor<CPDF_Dictionary>("EF");
   pEFDict->SetNewFor<CPDF_Reference>("F", pDoc, pFileStream->GetObjNum());
   return true;
 }

 FPDF_EXPORT unsigned long FPDF_CALLCONV
 FPDFAttachment_GetFile(FPDF_ATTACHMENT attachment,
                        void* buffer,
                        unsigned long buflen) {
   CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
   if (!pFile)
     return 0;

   CPDF_Stream* pFileStream = CPDF_FileSpec(pFile).GetFileStream();
   if (!pFileStream)
     return 0;

   return DecodeStreamMaybeCopyAndReturnLength(pFileStream, buffer, buflen);
 }
	// Copyright 2017 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.

	#include "public/fpdf_attachment.h"

	#include <memory>
	#include <utility>

	#include "constants/stream_dict_common.h"
	#include "core/fdrm/fx_crypt.h"
	#include "core/fpdfapi/parser/cpdf_array.h"
	#include "core/fpdfapi/parser/cpdf_dictionary.h"
	#include "core/fpdfapi/parser/cpdf_document.h"
	#include "core/fpdfapi/parser/cpdf_name.h"
	#include "core/fpdfapi/parser/cpdf_number.h"
	#include "core/fpdfapi/parser/cpdf_reference.h"
	#include "core/fpdfapi/parser/cpdf_stream.h"
	#include "core/fpdfapi/parser/cpdf_string.h"
	#include "core/fpdfapi/parser/fpdf_parser_decode.h"
	#include "core/fpdfdoc/cpdf_filespec.h"
	#include "core/fpdfdoc/cpdf_nametree.h"
	#include "core/fxcrt/cfx_datetime.h"
	#include "core/fxcrt/fx_extension.h"
	#include "core/fxcrt/fx_memory_wrappers.h"
	#include "fpdfsdk/cpdfsdk_helpers.h"
	#include "third_party/base/ptr_util.h"

	namespace {

	constexpr char kChecksumKey[] = "CheckSum";

	ByteString CFXByteStringHexDecode(const ByteString& bsHex) {
	std::unique_ptr<uint8_t, FxFreeDeleter> result;
	uint32_t size = 0;
	HexDecode(bsHex.raw_span(), &result, &size);
	return ByteString(result.get(), size);
	}

	ByteString GenerateMD5Base16(const void* contents, const unsigned long len) {
	uint8_t digest[16];
	CRYPT_MD5Generate({static_cast<const uint8_t*>(contents), len}, digest);
	char buf[32];
	for (int i = 0; i < 16; ++i)
	FXSYS_IntToTwoHexChars(digest[i], &buf[i * 2]);

	return ByteString(buf, 32);
	}

	} // namespace

	FPDF_EXPORT int FPDF_CALLCONV
	FPDFDoc_GetAttachmentCount(FPDF_DOCUMENT document) {
	CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
	if (!pDoc)
	return 0;

	return CPDF_NameTree(pDoc, "EmbeddedFiles").GetCount();
	}

	FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
	FPDFDoc_AddAttachment(FPDF_DOCUMENT document, FPDF_WIDESTRING name) {
	CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
	if (!pDoc)
	return nullptr;

	CPDF_Dictionary* pRoot = pDoc->GetRoot();
	if (!pRoot)
	return nullptr;

	WideString wsName = WideStringFromFPDFWideString(name);
	if (wsName.IsEmpty())
	return nullptr;

	// Retrieve the document's Names dictionary; create it if missing.
	CPDF_Dictionary* pNames = pRoot->GetDictFor("Names");
	if (!pNames) {
	pNames = pDoc->NewIndirect<CPDF_Dictionary>();
	pRoot->SetNewFor<CPDF_Reference>("Names", pDoc, pNames->GetObjNum());
	}

	// Create the EmbeddedFiles dictionary if missing.
	if (!pNames->GetDictFor("EmbeddedFiles")) {
	CPDF_Dictionary* pFiles = pDoc->NewIndirect<CPDF_Dictionary>();
	pFiles->SetNewFor<CPDF_Array>("Names");
	pNames->SetNewFor<CPDF_Reference>("EmbeddedFiles", pDoc,
	pFiles->GetObjNum());
	}

	// Set up the basic entries in the filespec dictionary.
	CPDF_Dictionary* pFile = pDoc->NewIndirect<CPDF_Dictionary>();
	pFile->SetNewFor<CPDF_Name>("Type", "Filespec");
	pFile->SetNewFor<CPDF_String>("UF", wsName);
	pFile->SetNewFor<CPDF_String>(pdfium::stream::kF, wsName);

	// Add the new attachment name and filespec into the document's EmbeddedFiles.
	CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
	if (!nameTree.AddValueAndName(pFile->MakeReference(pDoc), wsName)) {
	return nullptr;
	}

	return FPDFAttachmentFromCPDFObject(pFile);
	}

	FPDF_EXPORT FPDF_ATTACHMENT FPDF_CALLCONV
	FPDFDoc_GetAttachment(FPDF_DOCUMENT document, int index) {
	CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
	if (!pDoc \|\| index < 0)
	return nullptr;

	CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
	if (static_cast<size_t>(index) >= nameTree.GetCount())
	return nullptr;

	WideString csName;
	return FPDFAttachmentFromCPDFObject(
	nameTree.LookupValueAndName(index, &csName));
	}

	FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
	FPDFDoc_DeleteAttachment(FPDF_DOCUMENT document, int index) {
	CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
	if (!pDoc \|\| index < 0)
	return false;

	CPDF_NameTree nameTree(pDoc, "EmbeddedFiles");
	if (static_cast<size_t>(index) >= nameTree.GetCount())
	return false;

	return nameTree.DeleteValueAndName(index);
	}

	FPDF_EXPORT unsigned long FPDF_CALLCONV
	FPDFAttachment_GetName(FPDF_ATTACHMENT attachment,
	FPDF_WCHAR* buffer,
	unsigned long buflen) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	if (!pFile)
	return 0;

	return Utf16EncodeMaybeCopyAndReturnLength(CPDF_FileSpec(pFile).GetFileName(),
	buffer, buflen);
	}

	FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
	FPDFAttachment_HasKey(FPDF_ATTACHMENT attachment, FPDF_BYTESTRING key) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	if (!pFile)
	return 0;

	CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
	return pParamsDict ? pParamsDict->KeyExist(key) : 0;
	}

	FPDF_EXPORT FPDF_OBJECT_TYPE FPDF_CALLCONV
	FPDFAttachment_GetValueType(FPDF_ATTACHMENT attachment, FPDF_BYTESTRING key) {
	if (!FPDFAttachment_HasKey(attachment, key))
	return FPDF_OBJECT_UNKNOWN;

	CPDF_FileSpec spec(CPDFObjectFromFPDFAttachment(attachment));
	CPDF_Object* pObj = spec.GetParamsDict()->GetObjectFor(key);
	return pObj ? pObj->GetType() : FPDF_OBJECT_UNKNOWN;
	}

	FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
	FPDFAttachment_SetStringValue(FPDF_ATTACHMENT attachment,
	FPDF_BYTESTRING key,
	FPDF_WIDESTRING value) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	if (!pFile)
	return false;

	CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
	if (!pParamsDict)
	return false;

	ByteString bsKey = key;
	ByteString bsValue = ByteStringFromFPDFWideString(value);
	bool bEncodedAsHex = bsKey == kChecksumKey;
	if (bEncodedAsHex)
	bsValue = CFXByteStringHexDecode(bsValue);

	pParamsDict->SetNewFor<CPDF_String>(bsKey, bsValue, bEncodedAsHex);
	return true;
	}

	FPDF_EXPORT unsigned long FPDF_CALLCONV
	FPDFAttachment_GetStringValue(FPDF_ATTACHMENT attachment,
	FPDF_BYTESTRING key,
	FPDF_WCHAR* buffer,
	unsigned long buflen) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	if (!pFile)
	return 0;

	CPDF_Dictionary* pParamsDict = CPDF_FileSpec(pFile).GetParamsDict();
	if (!pParamsDict)
	return 0;

	ByteString bsKey = key;
	WideString value = pParamsDict->GetUnicodeTextFor(bsKey);
	if (bsKey == kChecksumKey && !value.IsEmpty()) {
	CPDF_String* stringValue = pParamsDict->GetObjectFor(bsKey)->AsString();
	if (stringValue->IsHex()) {
	ByteString encoded = PDF_EncodeString(stringValue->GetString(), true);
	value = pdfium::MakeRetain<CPDF_String>(nullptr, encoded, false)
	->GetUnicodeText();
	}
	}

	return Utf16EncodeMaybeCopyAndReturnLength(value, buffer, buflen);
	}

	FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
	FPDFAttachment_SetFile(FPDF_ATTACHMENT attachment,
	FPDF_DOCUMENT document,
	const void* contents,
	const unsigned long len) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
	if (!pFile \|\| !pFile->IsDictionary() \|\| !pDoc \|\| len > INT_MAX)
	return false;

	// An empty content must have a zero length.
	if (!contents && len != 0)
	return false;

	// Create a dictionary for the new embedded file stream.
	auto pFileStreamDict = pdfium::MakeRetain<CPDF_Dictionary>();
	CPDF_Dictionary* pParamsDict =
	pFileStreamDict->SetNewFor<CPDF_Dictionary>("Params");

	// Set the size of the new file in the dictionary.
	pFileStreamDict->SetNewFor<CPDF_Number>(pdfium::stream::kDL,
	static_cast<int>(len));
	pParamsDict->SetNewFor<CPDF_Number>("Size", static_cast<int>(len));

	// Set the creation date of the new attachment in the dictionary.
	CFX_DateTime dateTime = CFX_DateTime::Now();
	pParamsDict->SetNewFor<CPDF_String>(
	"CreationDate",
	ByteString::Format("D:%d%02d%02d%02d%02d%02d", dateTime.GetYear(),
	dateTime.GetMonth(), dateTime.GetDay(),
	dateTime.GetHour(), dateTime.GetMinute(),
	dateTime.GetSecond()),
	false);

	// Set the checksum of the new attachment in the dictionary.
	pParamsDict->SetNewFor<CPDF_String>(
	kChecksumKey, CFXByteStringHexDecode(GenerateMD5Base16(contents, len)),
	true);

	// Create the file stream and have the filespec dictionary link to it.
	std::unique_ptr<uint8_t, FxFreeDeleter> stream(FX_Alloc(uint8_t, len));
	memcpy(stream.get(), contents, len);
	CPDF_Stream* pFileStream = pDoc->NewIndirect<CPDF_Stream>(
	std::move(stream), len, std::move(pFileStreamDict));
	CPDF_Dictionary* pEFDict =
	pFile->AsDictionary()->SetNewFor<CPDF_Dictionary>("EF");
	pEFDict->SetNewFor<CPDF_Reference>("F", pDoc, pFileStream->GetObjNum());
	return true;
	}

	FPDF_EXPORT unsigned long FPDF_CALLCONV
	FPDFAttachment_GetFile(FPDF_ATTACHMENT attachment,
	void* buffer,
	unsigned long buflen) {
	CPDF_Object* pFile = CPDFObjectFromFPDFAttachment(attachment);
	if (!pFile)
	return 0;

	CPDF_Stream* pFileStream = CPDF_FileSpec(pFile).GetFileStream();
	if (!pFileStream)
	return 0;

	return DecodeStreamMaybeCopyAndReturnLength(pFileStream, buffer, buflen);
	}