The Tor Browser: gfx/skia/trunk/src/core/SkValidatingReadBuffer.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkValidatingReadBuffer.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkValidatingReadBuffer.cpp

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkBitmap.h"
 #include "SkErrorInternals.h"
 #include "SkValidatingReadBuffer.h"
 #include "SkStream.h"
 #include "SkTypeface.h"
 SkValidatingReadBuffer::SkValidatingReadBuffer(const void* data, size_t size) :
     fError(false) {
     this->setMemory(data, size);
     this->setFlags(SkReadBuffer::kValidation_Flag);
 }
 SkValidatingReadBuffer::~SkValidatingReadBuffer() {
 }
 bool SkValidatingReadBuffer::validate(bool isValid) {
     if (!fError && !isValid) {
         // When an error is found, send the read cursor to the end of the stream
         fReader.skip(fReader.available());
         fError = true;
     }
     return !fError;
 }
 bool SkValidatingReadBuffer::isValid() const {
     return !fError;
 }
 void SkValidatingReadBuffer::setMemory(const void* data, size_t size) {
     this->validate(IsPtrAlign4(data) && (SkAlign4(size) == size));
     if (!fError) {
         fReader.setMemory(data, size);
     }
 }
 const void* SkValidatingReadBuffer::skip(size_t size) {
     size_t inc = SkAlign4(size);
     const void* addr = fReader.peek();
     this->validate(IsPtrAlign4(addr) && fReader.isAvailable(inc));
     if (!fError) {
         fReader.skip(size);
     }
     return addr;
 }
 // All the methods in this file funnel down into either readInt(), readScalar() or skip(),
 // followed by a memcpy. So we've got all our validation in readInt(), readScalar() and skip();
 // if they fail they'll return a zero value or skip nothing, respectively, and set fError to
 // true, which the caller should check to see if an error occurred during the read operation.
 bool SkValidatingReadBuffer::readBool() {
     uint32_t value = this->readInt();
     // Boolean value should be either 0 or 1
     this->validate(!(value & ~1));
     return value != 0;
 }
 SkColor SkValidatingReadBuffer::readColor() {
     return this->readInt();
 }
 SkFixed SkValidatingReadBuffer::readFixed() {
     return this->readInt();
 }
 int32_t SkValidatingReadBuffer::readInt() {
     const size_t inc = sizeof(int32_t);
     this->validate(IsPtrAlign4(fReader.peek()) && fReader.isAvailable(inc));
     return fError ? 0 : fReader.readInt();
 }
 SkScalar SkValidatingReadBuffer::readScalar() {
     const size_t inc = sizeof(SkScalar);
     this->validate(IsPtrAlign4(fReader.peek()) && fReader.isAvailable(inc));
     return fError ? 0 : fReader.readScalar();
 }
 uint32_t SkValidatingReadBuffer::readUInt() {
     return this->readInt();
 }
 int32_t SkValidatingReadBuffer::read32() {
     return this->readInt();
 }
 void SkValidatingReadBuffer::readString(SkString* string) {
     const size_t len = this->readInt();
     const void* ptr = fReader.peek();
     const char* cptr = (const char*)ptr;
     // skip over the string + '\0' and then pad to a multiple of 4
     const size_t alignedSize = SkAlign4(len + 1);
     this->skip(alignedSize);
     if (!fError) {
         this->validate(cptr[len] == '\0');
     }
     if (!fError) {
         string->set(cptr, len);
     }
 }
 void* SkValidatingReadBuffer::readEncodedString(size_t* length, SkPaint::TextEncoding encoding) {
     const int32_t encodingType = this->readInt();
     this->validate(encodingType == encoding);
     *length = this->readInt();
     const void* ptr = this->skip(SkAlign4(*length));
     void* data = NULL;
     if (!fError) {
         data = sk_malloc_throw(*length);
         memcpy(data, ptr, *length);
     }
     return data;
 }
 void SkValidatingReadBuffer::readPoint(SkPoint* point) {
     point->fX = this->readScalar();
     point->fY = this->readScalar();
 }
 void SkValidatingReadBuffer::readMatrix(SkMatrix* matrix) {
     size_t size = 0;
     if (!fError) {
         size = matrix->readFromMemory(fReader.peek(), fReader.available());
         this->validate((SkAlign4(size) == size) && (0 != size));
     }
     if (!fError) {
         (void)this->skip(size);
     }
 }
 void SkValidatingReadBuffer::readIRect(SkIRect* rect) {
     const void* ptr = this->skip(sizeof(SkIRect));
     if (!fError) {
         memcpy(rect, ptr, sizeof(SkIRect));
     }
 }
 void SkValidatingReadBuffer::readRect(SkRect* rect) {
     const void* ptr = this->skip(sizeof(SkRect));
     if (!fError) {
         memcpy(rect, ptr, sizeof(SkRect));
     }
 }
 void SkValidatingReadBuffer::readRegion(SkRegion* region) {
     size_t size = 0;
     if (!fError) {
         size = region->readFromMemory(fReader.peek(), fReader.available());
         this->validate((SkAlign4(size) == size) && (0 != size));
     }
     if (!fError) {
         (void)this->skip(size);
     }
 }
 void SkValidatingReadBuffer::readPath(SkPath* path) {
     size_t size = 0;
     if (!fError) {
         size = path->readFromMemory(fReader.peek(), fReader.available());
         this->validate((SkAlign4(size) == size) && (0 != size));
     }
     if (!fError) {
         (void)this->skip(size);
     }
 }
 bool SkValidatingReadBuffer::readArray(void* value, size_t size, size_t elementSize) {
     const uint32_t count = this->getArrayCount();
     this->validate(size == count);
     (void)this->skip(sizeof(uint32_t)); // Skip array count
     const size_t byteLength = count * elementSize;
     const void* ptr = this->skip(SkAlign4(byteLength));
     if (!fError) {
         memcpy(value, ptr, byteLength);
         return true;
     }
     return false;
 }
 bool SkValidatingReadBuffer::readByteArray(void* value, size_t size) {
     return readArray(static_cast<unsigned char*>(value), size, sizeof(unsigned char));
 }
 bool SkValidatingReadBuffer::readColorArray(SkColor* colors, size_t size) {
     return readArray(colors, size, sizeof(SkColor));
 }
 bool SkValidatingReadBuffer::readIntArray(int32_t* values, size_t size) {
     return readArray(values, size, sizeof(int32_t));
 }
 bool SkValidatingReadBuffer::readPointArray(SkPoint* points, size_t size) {
     return readArray(points, size, sizeof(SkPoint));
 }
 bool SkValidatingReadBuffer::readScalarArray(SkScalar* values, size_t size) {
     return readArray(values, size, sizeof(SkScalar));
 }
 uint32_t SkValidatingReadBuffer::getArrayCount() {
     const size_t inc = sizeof(uint32_t);
     fError = fError || !IsPtrAlign4(fReader.peek()) || !fReader.isAvailable(inc);
     return fError ? 0 : *(uint32_t*)fReader.peek();
 }
 void SkValidatingReadBuffer::readBitmap(SkBitmap* bitmap) {
     const int width = this->readInt();
     const int height = this->readInt();
     const bool useBitmapHeap = this->readBool();
     const size_t length = this->readUInt();
     // A size of zero means the SkBitmap was simply flattened.
     if (!this->validate(!useBitmapHeap && (0 == length))) {
         return;
     }
     bitmap->unflatten(*this);
     this->validate((bitmap->width() == width) && (bitmap->height() == height));
 }
 SkTypeface* SkValidatingReadBuffer::readTypeface() {
     // TODO: Implement this (securely) when needed
     return NULL;
 }
 bool SkValidatingReadBuffer::validateAvailable(size_t size) {
     return this->validate((size <= SK_MaxU32) && fReader.isAvailable(static_cast<uint32_t>(size)));
 }
 SkFlattenable* SkValidatingReadBuffer::readFlattenable(SkFlattenable::Type type) {
     SkString name;
     this->readString(&name);
     if (fError) {
         return NULL;
     }
     // Is this the type we wanted ?
     const char* cname = name.c_str();
     SkFlattenable::Type baseType;
     if (!SkFlattenable::NameToType(cname, &baseType) || (baseType != type)) {
         return NULL;
     }
     SkFlattenable::Factory factory = SkFlattenable::NameToFactory(cname);
     if (NULL == factory) {
         return NULL; // writer failed to give us the flattenable
     }
     // if we get here, factory may still be null, but if that is the case, the
     // failure was ours, not the writer.
     SkFlattenable* obj = NULL;
     uint32_t sizeRecorded = this->readUInt();
     if (factory) {
         uint32_t offset = fReader.offset();
         obj = (*factory)(*this);
         // check that we read the amount we expected
         uint32_t sizeRead = fReader.offset() - offset;
         this->validate(sizeRecorded == sizeRead);
         if (fError) {
             // we could try to fix up the offset...
             delete obj;
             obj = NULL;
         }
     } else {
         // we must skip the remaining data
         this->skip(sizeRecorded);
         SkASSERT(false);
     }
     return obj;
 }

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gfx/skia/trunk/src/core/SkValidatingReadBuffer.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkValidatingReadBuffer.cpp