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Diffstat (limited to 'chromium/net/base/filter.cc')
| -rw-r--r-- | chromium/net/base/filter.cc | 400 |
1 files changed, 0 insertions, 400 deletions
diff --git a/chromium/net/base/filter.cc b/chromium/net/base/filter.cc deleted file mode 100644 index 42313fd9ffe..00000000000 --- a/chromium/net/base/filter.cc +++ /dev/null @@ -1,400 +0,0 @@ -// Copyright (c) 2011 The Chromium 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 "net/base/filter.h" - -#include "base/files/file_path.h" -#include "base/strings/string_util.h" -#include "net/base/gzip_filter.h" -#include "net/base/io_buffer.h" -#include "net/base/mime_util.h" -#include "net/base/sdch_filter.h" - -namespace { - -// Filter types (using canonical lower case only): -const char kDeflate[] = "deflate"; -const char kGZip[] = "gzip"; -const char kXGZip[] = "x-gzip"; -const char kSdch[] = "sdch"; -// compress and x-compress are currently not supported. If we decide to support -// them, we'll need the same mime type compatibility hack we have for gzip. For -// more information, see Firefox's nsHttpChannel::ProcessNormal. - -// Mime types: -const char kApplicationXGzip[] = "application/x-gzip"; -const char kApplicationGzip[] = "application/gzip"; -const char kApplicationXGunzip[] = "application/x-gunzip"; -const char kTextHtml[] = "text/html"; - -// Buffer size allocated when de-compressing data. -const int kFilterBufSize = 32 * 1024; - -} // namespace - -namespace net { - -FilterContext::~FilterContext() { -} - -Filter::~Filter() {} - -// static -Filter* Filter::Factory(const std::vector<FilterType>& filter_types, - const FilterContext& filter_context) { - if (filter_types.empty()) - return NULL; - - Filter* filter_list = NULL; // Linked list of filters. - for (size_t i = 0; i < filter_types.size(); i++) { - filter_list = PrependNewFilter(filter_types[i], filter_context, - kFilterBufSize, filter_list); - if (!filter_list) - return NULL; - } - return filter_list; -} - -// static -Filter* Filter::GZipFactory() { - return InitGZipFilter(FILTER_TYPE_GZIP, kFilterBufSize); -} - -// static -Filter* Filter::FactoryForTests(const std::vector<FilterType>& filter_types, - const FilterContext& filter_context, - int buffer_size) { - if (filter_types.empty()) - return NULL; - - Filter* filter_list = NULL; // Linked list of filters. - for (size_t i = 0; i < filter_types.size(); i++) { - filter_list = PrependNewFilter(filter_types[i], filter_context, - buffer_size, filter_list); - if (!filter_list) - return NULL; - } - return filter_list; -} - -Filter::FilterStatus Filter::ReadData(char* dest_buffer, int* dest_len) { - const int dest_buffer_capacity = *dest_len; - if (last_status_ == FILTER_ERROR) - return last_status_; - if (!next_filter_.get()) - return last_status_ = ReadFilteredData(dest_buffer, dest_len); - if (last_status_ == FILTER_NEED_MORE_DATA && !stream_data_len()) - return next_filter_->ReadData(dest_buffer, dest_len); - - do { - if (next_filter_->last_status() == FILTER_NEED_MORE_DATA) { - PushDataIntoNextFilter(); - if (FILTER_ERROR == last_status_) - return FILTER_ERROR; - } - *dest_len = dest_buffer_capacity; // Reset the input/output parameter. - next_filter_->ReadData(dest_buffer, dest_len); - if (FILTER_NEED_MORE_DATA == last_status_) - return next_filter_->last_status(); - - // In the case where this filter has data internally, and is indicating such - // with a last_status_ of FILTER_OK, but at the same time the next filter in - // the chain indicated it FILTER_NEED_MORE_DATA, we have to be cautious - // about confusing the caller. The API confusion can appear if we return - // FILTER_OK (suggesting we have more data in aggregate), but yet we don't - // populate our output buffer. When that is the case, we need to - // alternately call our filter element, and the next_filter element until we - // get out of this state (by pumping data into the next filter until it - // outputs data, or it runs out of data and reports that it NEED_MORE_DATA.) - } while (FILTER_OK == last_status_ && - FILTER_NEED_MORE_DATA == next_filter_->last_status() && - 0 == *dest_len); - - if (next_filter_->last_status() == FILTER_ERROR) - return FILTER_ERROR; - return FILTER_OK; -} - -bool Filter::FlushStreamBuffer(int stream_data_len) { - DCHECK_LE(stream_data_len, stream_buffer_size_); - if (stream_data_len <= 0 || stream_data_len > stream_buffer_size_) - return false; - - DCHECK(stream_buffer()); - // Bail out if there is more data in the stream buffer to be filtered. - if (!stream_buffer() || stream_data_len_) - return false; - - next_stream_data_ = stream_buffer()->data(); - stream_data_len_ = stream_data_len; - return true; -} - -// static -Filter::FilterType Filter::ConvertEncodingToType( - const std::string& filter_type) { - FilterType type_id; - if (LowerCaseEqualsASCII(filter_type, kDeflate)) { - type_id = FILTER_TYPE_DEFLATE; - } else if (LowerCaseEqualsASCII(filter_type, kGZip) || - LowerCaseEqualsASCII(filter_type, kXGZip)) { - type_id = FILTER_TYPE_GZIP; - } else if (LowerCaseEqualsASCII(filter_type, kSdch)) { - type_id = FILTER_TYPE_SDCH; - } else { - // Note we also consider "identity" and "uncompressed" UNSUPPORTED as - // filter should be disabled in such cases. - type_id = FILTER_TYPE_UNSUPPORTED; - } - return type_id; -} - -// static -void Filter::FixupEncodingTypes( - const FilterContext& filter_context, - std::vector<FilterType>* encoding_types) { - std::string mime_type; - bool success = filter_context.GetMimeType(&mime_type); - DCHECK(success || mime_type.empty()); - - if ((1 == encoding_types->size()) && - (FILTER_TYPE_GZIP == encoding_types->front())) { - if (LowerCaseEqualsASCII(mime_type, kApplicationXGzip) || - LowerCaseEqualsASCII(mime_type, kApplicationGzip) || - LowerCaseEqualsASCII(mime_type, kApplicationXGunzip)) - // The server has told us that it sent us gziped content with a gzip - // content encoding. Sadly, Apache mistakenly sets these headers for all - // .gz files. We match Firefox's nsHttpChannel::ProcessNormal and ignore - // the Content-Encoding here. - encoding_types->clear(); - - GURL url; - success = filter_context.GetURL(&url); - DCHECK(success); - base::FilePath filename = - base::FilePath().AppendASCII(url.ExtractFileName()); - base::FilePath::StringType extension = filename.Extension(); - - if (filter_context.IsDownload()) { - // We don't want to decompress gzipped files when the user explicitly - // asks to download them. - // For the case of svgz files, we use the extension to distinguish - // between svgz files and svg files compressed with gzip by the server. - // When viewing a .svgz file, we need to uncompress it, but we don't - // want to do that when downloading. - // See Firefox's nonDecodableExtensions in nsExternalHelperAppService.cpp - if (EndsWith(extension, FILE_PATH_LITERAL(".gz"), false) || - LowerCaseEqualsASCII(extension, ".tgz") || - LowerCaseEqualsASCII(extension, ".svgz")) - encoding_types->clear(); - } else { - // When the user does not explicitly ask to download a file, if we get a - // supported mime type, then we attempt to decompress in order to view it. - // However, if it's not a supported mime type, then we will attempt to - // download it, and in that case, don't decompress .gz/.tgz files. - if ((EndsWith(extension, FILE_PATH_LITERAL(".gz"), false) || - LowerCaseEqualsASCII(extension, ".tgz")) && - !IsSupportedMimeType(mime_type)) - encoding_types->clear(); - } - } - - // If the request was for SDCH content, then we might need additional fixups. - if (!filter_context.IsSdchResponse()) { - // It was not an SDCH request, so we'll just record stats. - if (1 < encoding_types->size()) { - // Multiple filters were intended to only be used for SDCH (thus far!) - SdchManager::SdchErrorRecovery( - SdchManager::MULTIENCODING_FOR_NON_SDCH_REQUEST); - } - if ((1 == encoding_types->size()) && - (FILTER_TYPE_SDCH == encoding_types->front())) { - SdchManager::SdchErrorRecovery( - SdchManager::SDCH_CONTENT_ENCODE_FOR_NON_SDCH_REQUEST); - } - return; - } - - // The request was tagged as an SDCH request, which means the server supplied - // a dictionary, and we advertised it in the request. Some proxies will do - // very strange things to the request, or the response, so we have to handle - // them gracefully. - - // If content encoding included SDCH, then everything is "relatively" fine. - if (!encoding_types->empty() && - (FILTER_TYPE_SDCH == encoding_types->front())) { - // Some proxies (found currently in Argentina) strip the Content-Encoding - // text from "sdch,gzip" to a mere "sdch" without modifying the compressed - // payload. To handle this gracefully, we simulate the "probably" deleted - // ",gzip" by appending a tentative gzip decode, which will default to a - // no-op pass through filter if it doesn't get gzip headers where expected. - if (1 == encoding_types->size()) { - encoding_types->push_back(FILTER_TYPE_GZIP_HELPING_SDCH); - SdchManager::SdchErrorRecovery( - SdchManager::OPTIONAL_GUNZIP_ENCODING_ADDED); - } - return; - } - - // There are now several cases to handle for an SDCH request. Foremost, if - // the outbound request was stripped so as not to advertise support for - // encodings, we might get back content with no encoding, or (for example) - // just gzip. We have to be sure that any changes we make allow for such - // minimal coding to work. That issue is why we use TENTATIVE filters if we - // add any, as those filters sniff the content, and act as pass-through - // filters if headers are not found. - - // If the outbound GET is not modified, then the server will generally try to - // send us SDCH encoded content. As that content returns, there are several - // corruptions of the header "content-encoding" that proxies may perform (and - // have been detected in the wild). We already dealt with the a honest - // content encoding of "sdch,gzip" being corrupted into "sdch" with on change - // of the actual content. Another common corruption is to either disscard - // the accurate content encoding, or to replace it with gzip only (again, with - // no change in actual content). The last observed corruption it to actually - // change the content, such as by re-gzipping it, and that may happen along - // with corruption of the stated content encoding (wow!). - - // The one unresolved failure mode comes when we advertise a dictionary, and - // the server tries to *send* a gzipped file (not gzip encode content), and - // then we could do a gzip decode :-(. Since SDCH is only (currently) - // supported server side on paths that only send HTML content, this mode has - // never surfaced in the wild (and is unlikely to). - // We will gather a lot of stats as we perform the fixups - if (StartsWithASCII(mime_type, kTextHtml, false)) { - // Suspicious case: Advertised dictionary, but server didn't use sdch, and - // we're HTML tagged. - if (encoding_types->empty()) { - SdchManager::SdchErrorRecovery( - SdchManager::ADDED_CONTENT_ENCODING); - } else if (1 == encoding_types->size()) { - SdchManager::SdchErrorRecovery( - SdchManager::FIXED_CONTENT_ENCODING); - } else { - SdchManager::SdchErrorRecovery( - SdchManager::FIXED_CONTENT_ENCODINGS); - } - } else { - // Remarkable case!?! We advertised an SDCH dictionary, content-encoding - // was not marked for SDCH processing: Why did the server suggest an SDCH - // dictionary in the first place??. Also, the content isn't - // tagged as HTML, despite the fact that SDCH encoding is mostly likely for - // HTML: Did some anti-virus system strip this tag (sometimes they strip - // accept-encoding headers on the request)?? Does the content encoding not - // start with "text/html" for some other reason?? We'll report this as a - // fixup to a binary file, but it probably really is text/html (some how). - if (encoding_types->empty()) { - SdchManager::SdchErrorRecovery( - SdchManager::BINARY_ADDED_CONTENT_ENCODING); - } else if (1 == encoding_types->size()) { - SdchManager::SdchErrorRecovery( - SdchManager::BINARY_FIXED_CONTENT_ENCODING); - } else { - SdchManager::SdchErrorRecovery( - SdchManager::BINARY_FIXED_CONTENT_ENCODINGS); - } - } - - // Leave the existing encoding type to be processed first, and add our - // tentative decodings to be done afterwards. Vodaphone UK reportedyl will - // perform a second layer of gzip encoding atop the server's sdch,gzip - // encoding, and then claim that the content encoding is a mere gzip. As a - // result we'll need (in that case) to do the gunzip, plus our tentative - // gunzip and tentative SDCH decoding. - // This approach nicely handles the empty() list as well, and should work with - // other (as yet undiscovered) proxies the choose to re-compressed with some - // other encoding (such as bzip2, etc.). - encoding_types->insert(encoding_types->begin(), - FILTER_TYPE_GZIP_HELPING_SDCH); - encoding_types->insert(encoding_types->begin(), FILTER_TYPE_SDCH_POSSIBLE); - return; -} - -Filter::Filter() - : stream_buffer_(NULL), - stream_buffer_size_(0), - next_stream_data_(NULL), - stream_data_len_(0), - last_status_(FILTER_NEED_MORE_DATA) {} - -Filter::FilterStatus Filter::CopyOut(char* dest_buffer, int* dest_len) { - int out_len; - int input_len = *dest_len; - *dest_len = 0; - - if (0 == stream_data_len_) - return Filter::FILTER_NEED_MORE_DATA; - - out_len = std::min(input_len, stream_data_len_); - memcpy(dest_buffer, next_stream_data_, out_len); - *dest_len += out_len; - stream_data_len_ -= out_len; - if (0 == stream_data_len_) { - next_stream_data_ = NULL; - return Filter::FILTER_NEED_MORE_DATA; - } else { - next_stream_data_ += out_len; - return Filter::FILTER_OK; - } -} - -// static -Filter* Filter::InitGZipFilter(FilterType type_id, int buffer_size) { - scoped_ptr<GZipFilter> gz_filter(new GZipFilter()); - gz_filter->InitBuffer(buffer_size); - return gz_filter->InitDecoding(type_id) ? gz_filter.release() : NULL; -} - -// static -Filter* Filter::InitSdchFilter(FilterType type_id, - const FilterContext& filter_context, - int buffer_size) { - scoped_ptr<SdchFilter> sdch_filter(new SdchFilter(filter_context)); - sdch_filter->InitBuffer(buffer_size); - return sdch_filter->InitDecoding(type_id) ? sdch_filter.release() : NULL; -} - -// static -Filter* Filter::PrependNewFilter(FilterType type_id, - const FilterContext& filter_context, - int buffer_size, - Filter* filter_list) { - scoped_ptr<Filter> first_filter; // Soon to be start of chain. - switch (type_id) { - case FILTER_TYPE_GZIP_HELPING_SDCH: - case FILTER_TYPE_DEFLATE: - case FILTER_TYPE_GZIP: - first_filter.reset(InitGZipFilter(type_id, buffer_size)); - break; - case FILTER_TYPE_SDCH: - case FILTER_TYPE_SDCH_POSSIBLE: - first_filter.reset(InitSdchFilter(type_id, filter_context, buffer_size)); - break; - default: - break; - } - - if (!first_filter.get()) - return NULL; - - first_filter->next_filter_.reset(filter_list); - return first_filter.release(); -} - -void Filter::InitBuffer(int buffer_size) { - DCHECK(!stream_buffer()); - DCHECK_GT(buffer_size, 0); - stream_buffer_ = new IOBuffer(buffer_size); - stream_buffer_size_ = buffer_size; -} - -void Filter::PushDataIntoNextFilter() { - IOBuffer* next_buffer = next_filter_->stream_buffer(); - int next_size = next_filter_->stream_buffer_size(); - last_status_ = ReadFilteredData(next_buffer->data(), &next_size); - if (FILTER_ERROR != last_status_) - next_filter_->FlushStreamBuffer(next_size); -} - -} // namespace net |