1 //
2 // Copyright (C) 2011 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16 
17 #include "update_engine/common/download_action.h"
18 
19 #include <errno.h>
20 
21 #include <algorithm>
22 #include <string>
23 
24 #include <base/files/file_path.h>
25 #include <base/metrics/statistics_recorder.h>
26 #include <base/strings/stringprintf.h>
27 
28 #include "update_engine/common/action_pipe.h"
29 #include "update_engine/common/boot_control_interface.h"
30 #include "update_engine/common/error_code_utils.h"
31 #include "update_engine/common/multi_range_http_fetcher.h"
32 #include "update_engine/common/prefs_interface.h"
33 #include "update_engine/common/utils.h"
34 
35 using base::FilePath;
36 using std::string;
37 
38 namespace chromeos_update_engine {
39 
40 DownloadAction::DownloadAction(PrefsInterface* prefs,
41                                BootControlInterface* boot_control,
42                                HardwareInterface* hardware,
43                                HttpFetcher* http_fetcher,
44                                bool interactive)
45     : prefs_(prefs),
46       boot_control_(boot_control),
47       hardware_(hardware),
48       http_fetcher_(new MultiRangeHttpFetcher(http_fetcher)),
49       interactive_(interactive),
50       code_(ErrorCode::kSuccess),
51       delegate_(nullptr) {}
52 
53 DownloadAction::~DownloadAction() {}
54 
55 void DownloadAction::PerformAction() {
56   http_fetcher_->set_delegate(this);
57 
58   // Get the InstallPlan and read it
59   CHECK(HasInputObject());
60   install_plan_ = GetInputObject();
61   install_plan_.Dump();
62 
63   bytes_received_ = 0;
64   bytes_received_previous_payloads_ = 0;
65   bytes_total_ = 0;
66   for (const auto& payload : install_plan_.payloads)
67     bytes_total_ += payload.size;
68 
69   if (install_plan_.is_resume) {
70     int64_t payload_index = 0;
71     if (prefs_->GetInt64(kPrefsUpdateStatePayloadIndex, &payload_index) &&
72         static_cast<size_t>(payload_index) < install_plan_.payloads.size()) {
73       // Save the index for the resume payload before downloading any previous
74       // payload, otherwise it will be overwritten.
75       resume_payload_index_ = payload_index;
76       for (int i = 0; i < payload_index; i++)
77         install_plan_.payloads[i].already_applied = true;
78     }
79   }
80   CHECK_GE(install_plan_.payloads.size(), 1UL);
81   if (!payload_)
82     payload_ = &install_plan_.payloads[0];
83 
84   LOG(INFO) << "Marking new slot as unbootable";
85   if (!boot_control_->MarkSlotUnbootable(install_plan_.target_slot)) {
86     LOG(WARNING) << "Unable to mark new slot "
87                  << BootControlInterface::SlotName(install_plan_.target_slot)
88                  << ". Proceeding with the update anyway.";
89   }
90 
91   StartDownloading();
92 }
93 
94 bool DownloadAction::LoadCachedManifest(int64_t manifest_size) {
95   std::string cached_manifest_bytes;
96   if (!prefs_->GetString(kPrefsManifestBytes, &cached_manifest_bytes) ||
97       cached_manifest_bytes.size() <= 0) {
98     LOG(INFO) << "Cached Manifest data not found";
99     return false;
100   }
101   if (static_cast<int64_t>(cached_manifest_bytes.size()) != manifest_size) {
102     LOG(WARNING) << "Cached metadata has unexpected size: "
103                  << cached_manifest_bytes.size() << " vs. " << manifest_size;
104     return false;
105   }
106 
107   ErrorCode error;
108   const bool success =
109       delta_performer_->Write(
110           cached_manifest_bytes.data(), cached_manifest_bytes.size(), &error) &&
111       delta_performer_->IsManifestValid();
112   if (success) {
113     LOG(INFO) << "Successfully parsed cached manifest";
114   } else {
115     // If parsing of cached data failed, fall back to fetch them using HTTP
116     LOG(WARNING) << "Cached manifest data fails to load, error code:"
117                  << static_cast<int>(error) << "," << error;
118   }
119   return success;
120 }
121 
122 void DownloadAction::StartDownloading() {
123   download_active_ = true;
124   http_fetcher_->ClearRanges();
125 
126   if (delta_performer_ != nullptr) {
127     LOG(INFO) << "Using writer for test.";
128   } else {
129     delta_performer_.reset(new DeltaPerformer(prefs_,
130                                               boot_control_,
131                                               hardware_,
132                                               delegate_,
133                                               &install_plan_,
134                                               payload_,
135                                               interactive_));
136   }
137 
138   if (install_plan_.is_resume &&
139       payload_ == &install_plan_.payloads[resume_payload_index_]) {
140     // Resuming an update so parse the cached manifest first
141     int64_t manifest_metadata_size = 0;
142     int64_t manifest_signature_size = 0;
143     prefs_->GetInt64(kPrefsManifestMetadataSize, &manifest_metadata_size);
144     prefs_->GetInt64(kPrefsManifestSignatureSize, &manifest_signature_size);
145 
146     // TODO(zhangkelvin) Add unittest for success and fallback route
147     if (!LoadCachedManifest(manifest_metadata_size + manifest_signature_size)) {
148       if (delta_performer_) {
149         // Create a new DeltaPerformer to reset all its state
150         delta_performer_ = std::make_unique<DeltaPerformer>(prefs_,
151                                                             boot_control_,
152                                                             hardware_,
153                                                             delegate_,
154                                                             &install_plan_,
155                                                             payload_,
156                                                             interactive_);
157       }
158       http_fetcher_->AddRange(base_offset_,
159                               manifest_metadata_size + manifest_signature_size);
160     }
161 
162     // If there're remaining unprocessed data blobs, fetch them. Be careful
163     // not to request data beyond the end of the payload to avoid 416 HTTP
164     // response error codes.
165     int64_t next_data_offset = 0;
166     prefs_->GetInt64(kPrefsUpdateStateNextDataOffset, &next_data_offset);
167     uint64_t resume_offset =
168         manifest_metadata_size + manifest_signature_size + next_data_offset;
169     if (!payload_->size) {
170       http_fetcher_->AddRange(base_offset_ + resume_offset);
171     } else if (resume_offset < payload_->size) {
172       http_fetcher_->AddRange(base_offset_ + resume_offset,
173                               payload_->size - resume_offset);
174     }
175   } else {
176     if (payload_->size) {
177       http_fetcher_->AddRange(base_offset_, payload_->size);
178     } else {
179       // If no payload size is passed we assume we read until the end of the
180       // stream.
181       http_fetcher_->AddRange(base_offset_);
182     }
183   }
184 
185   http_fetcher_->BeginTransfer(install_plan_.download_url);
186 }
187 
188 void DownloadAction::SuspendAction() {
189   http_fetcher_->Pause();
190 }
191 
192 void DownloadAction::ResumeAction() {
193   http_fetcher_->Unpause();
194 }
195 
196 void DownloadAction::TerminateProcessing() {
197   if (delta_performer_) {
198     delta_performer_->Close();
199     delta_performer_.reset();
200   }
201   download_active_ = false;
202   // Terminates the transfer. The action is terminated, if necessary, when the
203   // TransferTerminated callback is received.
204   http_fetcher_->TerminateTransfer();
205 }
206 
207 void DownloadAction::SeekToOffset(off_t offset) {
208   bytes_received_ = offset;
209 }
210 
211 bool DownloadAction::ReceivedBytes(HttpFetcher* fetcher,
212                                    const void* bytes,
213                                    size_t length) {
214   bytes_received_ += length;
215   uint64_t bytes_downloaded_total =
216       bytes_received_previous_payloads_ + bytes_received_;
217   if (delegate_ && download_active_) {
218     delegate_->BytesReceived(length, bytes_downloaded_total, bytes_total_);
219   }
220   if (delta_performer_ && !delta_performer_->Write(bytes, length, &code_)) {
221     if (code_ != ErrorCode::kSuccess) {
222       LOG(ERROR) << "Error " << utils::ErrorCodeToString(code_) << " (" << code_
223                  << ") in DeltaPerformer's Write method when "
224                  << "processing the received payload -- Terminating processing";
225     }
226     // Don't tell the action processor that the action is complete until we get
227     // the TransferTerminated callback. Otherwise, this and the HTTP fetcher
228     // objects may get destroyed before all callbacks are complete.
229     TerminateProcessing();
230     return false;
231   }
232 
233   return true;
234 }
235 
236 void DownloadAction::TransferComplete(HttpFetcher* fetcher, bool successful) {
237   if (delta_performer_) {
238     LOG_IF(WARNING, delta_performer_->Close() != 0)
239         << "Error closing the writer.";
240   }
241   download_active_ = false;
242   ErrorCode code =
243       successful ? ErrorCode::kSuccess : ErrorCode::kDownloadTransferError;
244   if (code == ErrorCode::kSuccess) {
245     if (delta_performer_ && !payload_->already_applied)
246       code = delta_performer_->VerifyPayload(payload_->hash, payload_->size);
247     if (code == ErrorCode::kSuccess) {
248       CHECK_EQ(install_plan_.payloads.size(), 1UL);
249       // All payloads have been applied and verified.
250       if (delegate_)
251         delegate_->DownloadComplete();
252 
253       // Log UpdateEngine.DownloadAction.* histograms to help diagnose
254       // long-blocking operations.
255       std::string histogram_output;
256       base::StatisticsRecorder::WriteGraph("UpdateEngine.DownloadAction.",
257                                            &histogram_output);
258       LOG(INFO) << histogram_output;
259     } else {
260       LOG(ERROR) << "Download of " << install_plan_.download_url
261                  << " failed due to payload verification error.";
262     }
263   }
264 
265   // Write the path to the output pipe if we're successful.
266   if (code == ErrorCode::kSuccess && HasOutputPipe())
267     SetOutputObject(install_plan_);
268   processor_->ActionComplete(this, code);
269 }
270 
271 void DownloadAction::TransferTerminated(HttpFetcher* fetcher) {
272   if (code_ != ErrorCode::kSuccess) {
273     processor_->ActionComplete(this, code_);
274   } else if (payload_->already_applied) {
275     LOG(INFO) << "TransferTerminated with ErrorCode::kSuccess when the current "
276                  "payload has already applied, treating as TransferComplete.";
277     TransferComplete(fetcher, true);
278   }
279 }
280 
281 }  // namespace chromeos_update_engine
282