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/omaha_response_handler_action.h"
18
19 #include <string>
20
21 #include <base/logging.h>
22 #include <base/strings/string_util.h>
23 #include <policy/device_policy.h>
24
25 #include "update_engine/common/constants.h"
26 #include "update_engine/common/hardware_interface.h"
27 #include "update_engine/common/prefs_interface.h"
28 #include "update_engine/common/utils.h"
29 #include "update_engine/connection_manager_interface.h"
30 #include "update_engine/omaha_request_params.h"
31 #include "update_engine/payload_consumer/delta_performer.h"
32 #include "update_engine/payload_state_interface.h"
33
34 using std::string;
35
36 namespace chromeos_update_engine {
37
OmahaResponseHandlerAction(SystemState * system_state)38 OmahaResponseHandlerAction::OmahaResponseHandlerAction(
39 SystemState* system_state)
40 : OmahaResponseHandlerAction(system_state,
41 constants::kOmahaResponseDeadlineFile) {}
42
OmahaResponseHandlerAction(SystemState * system_state,const string & deadline_file)43 OmahaResponseHandlerAction::OmahaResponseHandlerAction(
44 SystemState* system_state, const string& deadline_file)
45 : system_state_(system_state),
46 got_no_update_response_(false),
47 key_path_(constants::kUpdatePayloadPublicKeyPath),
48 deadline_file_(deadline_file) {}
49
PerformAction()50 void OmahaResponseHandlerAction::PerformAction() {
51 CHECK(HasInputObject());
52 ScopedActionCompleter completer(processor_, this);
53 const OmahaResponse& response = GetInputObject();
54 if (!response.update_exists) {
55 got_no_update_response_ = true;
56 LOG(INFO) << "There are no updates. Aborting.";
57 return;
58 }
59
60 // All decisions as to which URL should be used have already been done. So,
61 // make the current URL as the download URL.
62 string current_url = system_state_->payload_state()->GetCurrentUrl();
63 if (current_url.empty()) {
64 // This shouldn't happen as we should always supply the HTTPS backup URL.
65 // Handling this anyway, just in case.
66 LOG(ERROR) << "There are no suitable URLs in the response to use.";
67 completer.set_code(ErrorCode::kOmahaResponseInvalid);
68 return;
69 }
70
71 install_plan_.download_url = current_url;
72 install_plan_.version = response.version;
73
74 OmahaRequestParams* const params = system_state_->request_params();
75 PayloadStateInterface* const payload_state = system_state_->payload_state();
76
77 // If we're using p2p to download and there is a local peer, use it.
78 if (payload_state->GetUsingP2PForDownloading() &&
79 !payload_state->GetP2PUrl().empty()) {
80 LOG(INFO) << "Replacing URL " << install_plan_.download_url
81 << " with local URL " << payload_state->GetP2PUrl()
82 << " since p2p is enabled.";
83 install_plan_.download_url = payload_state->GetP2PUrl();
84 payload_state->SetUsingP2PForDownloading(true);
85 }
86
87 // Fill up the other properties based on the response.
88 install_plan_.payload_size = response.size;
89 install_plan_.payload_hash = response.hash;
90 install_plan_.metadata_size = response.metadata_size;
91 install_plan_.metadata_signature = response.metadata_signature;
92 install_plan_.public_key_rsa = response.public_key_rsa;
93 install_plan_.hash_checks_mandatory = AreHashChecksMandatory(response);
94 install_plan_.is_resume =
95 DeltaPerformer::CanResumeUpdate(system_state_->prefs(), response.hash);
96 if (install_plan_.is_resume) {
97 payload_state->UpdateResumed();
98 } else {
99 payload_state->UpdateRestarted();
100 LOG_IF(WARNING, !DeltaPerformer::ResetUpdateProgress(
101 system_state_->prefs(), false))
102 << "Unable to reset the update progress.";
103 LOG_IF(WARNING, !system_state_->prefs()->SetString(
104 kPrefsUpdateCheckResponseHash, response.hash))
105 << "Unable to save the update check response hash.";
106 }
107 install_plan_.payload_type = response.is_delta_payload
108 ? InstallPayloadType::kDelta
109 : InstallPayloadType::kFull;
110
111 install_plan_.source_slot = system_state_->boot_control()->GetCurrentSlot();
112 install_plan_.target_slot = install_plan_.source_slot == 0 ? 1 : 0;
113
114 // The Omaha response doesn't include the channel name for this image, so we
115 // use the download_channel we used during the request to tag the target slot.
116 // This will be used in the next boot to know the channel the image was
117 // downloaded from.
118 string current_channel_key =
119 kPrefsChannelOnSlotPrefix + std::to_string(install_plan_.target_slot);
120 system_state_->prefs()->SetString(current_channel_key,
121 params->download_channel());
122
123 if (params->to_more_stable_channel() && params->is_powerwash_allowed())
124 install_plan_.powerwash_required = true;
125
126 TEST_AND_RETURN(HasOutputPipe());
127 if (HasOutputPipe())
128 SetOutputObject(install_plan_);
129 LOG(INFO) << "Using this install plan:";
130 install_plan_.Dump();
131
132 // Send the deadline data (if any) to Chrome through a file. This is a pretty
133 // hacky solution but should be OK for now.
134 //
135 // TODO(petkov): Re-architect this to avoid communication through a
136 // file. Ideally, we would include this information in D-Bus's GetStatus
137 // method and UpdateStatus signal. A potential issue is that update_engine may
138 // be unresponsive during an update download.
139 if (!deadline_file_.empty()) {
140 utils::WriteFile(deadline_file_.c_str(),
141 response.deadline.data(),
142 response.deadline.size());
143 chmod(deadline_file_.c_str(), S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
144 }
145
146 completer.set_code(ErrorCode::kSuccess);
147 }
148
AreHashChecksMandatory(const OmahaResponse & response)149 bool OmahaResponseHandlerAction::AreHashChecksMandatory(
150 const OmahaResponse& response) {
151 // We sometimes need to waive the hash checks in order to download from
152 // sources that don't provide hashes, such as dev server.
153 // At this point UpdateAttempter::IsAnyUpdateSourceAllowed() has already been
154 // checked, so an unofficial update URL won't get this far unless it's OK to
155 // use without a hash. Additionally, we want to always waive hash checks on
156 // unofficial builds (i.e. dev/test images).
157 // The end result is this:
158 // * Base image:
159 // - Official URLs require a hash.
160 // - Unofficial URLs only get this far if the IsAnyUpdateSourceAllowed()
161 // devmode/debugd checks pass, in which case the hash is waived.
162 // * Dev/test image:
163 // - Any URL is allowed through with no hash checking.
164 if (!system_state_->request_params()->IsUpdateUrlOfficial() ||
165 !system_state_->hardware()->IsOfficialBuild()) {
166 // Still do a hash check if a public key is included.
167 if (!response.public_key_rsa.empty()) {
168 // The autoupdate_CatchBadSignatures test checks for this string
169 // in log-files. Keep in sync.
170 LOG(INFO) << "Mandating payload hash checks since Omaha Response "
171 << "for unofficial build includes public RSA key.";
172 return true;
173 } else {
174 LOG(INFO) << "Waiving payload hash checks for unofficial update URL.";
175 return false;
176 }
177 }
178
179 // If we're using p2p, |install_plan_.download_url| may contain a
180 // HTTP URL even if |response.payload_urls| contain only HTTPS URLs.
181 if (!base::StartsWith(install_plan_.download_url, "https://",
182 base::CompareCase::INSENSITIVE_ASCII)) {
183 LOG(INFO) << "Mandating hash checks since download_url is not HTTPS.";
184 return true;
185 }
186
187 // TODO(jaysri): VALIDATION: For official builds, we currently waive hash
188 // checks for HTTPS until we have rolled out at least once and are confident
189 // nothing breaks. chromium-os:37082 tracks turning this on for HTTPS
190 // eventually.
191
192 // Even if there's a single non-HTTPS URL, make the hash checks as
193 // mandatory because we could be downloading the payload from any URL later
194 // on. It's really hard to do book-keeping based on each byte being
195 // downloaded to see whether we only used HTTPS throughout.
196 for (size_t i = 0; i < response.payload_urls.size(); i++) {
197 if (!base::StartsWith(response.payload_urls[i], "https://",
198 base::CompareCase::INSENSITIVE_ASCII)) {
199 LOG(INFO) << "Mandating payload hash checks since Omaha response "
200 << "contains non-HTTPS URL(s)";
201 return true;
202 }
203 }
204
205 LOG(INFO) << "Waiving payload hash checks since Omaha response "
206 << "only has HTTPS URL(s)";
207 return false;
208 }
209
210 } // namespace chromeos_update_engine
211