//
// Copyright (C) 2012 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#include "update_engine/omaha_request_action.h"
#include <inttypes.h>
#include <map>
#include <sstream>
#include <string>
#include <vector>
#include <base/bind.h>
#include <base/logging.h>
#include <base/rand_util.h>
#include <base/strings/string_number_conversions.h>
#include <base/strings/string_util.h>
#include <base/strings/stringprintf.h>
#include <base/time/time.h>
#include <expat.h>
#include <metrics/metrics_library.h>
#include "update_engine/common/action_pipe.h"
#include "update_engine/common/constants.h"
#include "update_engine/common/hardware_interface.h"
#include "update_engine/common/hash_calculator.h"
#include "update_engine/common/platform_constants.h"
#include "update_engine/common/prefs_interface.h"
#include "update_engine/common/utils.h"
#include "update_engine/connection_manager.h"
#include "update_engine/metrics.h"
#include "update_engine/metrics_utils.h"
#include "update_engine/omaha_request_params.h"
#include "update_engine/p2p_manager.h"
#include "update_engine/payload_state_interface.h"
using base::Time;
using base::TimeDelta;
using std::map;
using std::string;
using std::vector;
namespace chromeos_update_engine {
// List of custom pair tags that we interpret in the Omaha Response:
static const char* kTagDeadline = "deadline";
static const char* kTagDisablePayloadBackoff = "DisablePayloadBackoff";
static const char* kTagVersion = "version";
// Deprecated: "IsDelta"
static const char* kTagIsDeltaPayload = "IsDeltaPayload";
static const char* kTagMaxFailureCountPerUrl = "MaxFailureCountPerUrl";
static const char* kTagMaxDaysToScatter = "MaxDaysToScatter";
// Deprecated: "ManifestSignatureRsa"
// Deprecated: "ManifestSize"
static const char* kTagMetadataSignatureRsa = "MetadataSignatureRsa";
static const char* kTagMetadataSize = "MetadataSize";
static const char* kTagMoreInfo = "MoreInfo";
// Deprecated: "NeedsAdmin"
static const char* kTagPrompt = "Prompt";
static const char* kTagSha256 = "sha256";
static const char* kTagDisableP2PForDownloading = "DisableP2PForDownloading";
static const char* kTagDisableP2PForSharing = "DisableP2PForSharing";
static const char* kTagPublicKeyRsa = "PublicKeyRsa";
static const char* kOmahaUpdaterVersion = "0.1.0.0";
namespace {
// Returns an XML ping element attribute assignment with attribute
// |name| and value |ping_days| if |ping_days| has a value that needs
// to be sent, or an empty string otherwise.
string GetPingAttribute(const string& name, int ping_days) {
if (ping_days > 0 || ping_days == OmahaRequestAction::kNeverPinged)
return base::StringPrintf(" %s=\"%d\"", name.c_str(), ping_days);
return "";
}
// Returns an XML ping element if any of the elapsed days need to be
// sent, or an empty string otherwise.
string GetPingXml(int ping_active_days, int ping_roll_call_days) {
string ping_active = GetPingAttribute("a", ping_active_days);
string ping_roll_call = GetPingAttribute("r", ping_roll_call_days);
if (!ping_active.empty() || !ping_roll_call.empty()) {
return base::StringPrintf(" <ping active=\"1\"%s%s></ping>\n",
ping_active.c_str(),
ping_roll_call.c_str());
}
return "";
}
// Returns an XML that goes into the body of the <app> element of the Omaha
// request based on the given parameters.
string GetAppBody(const OmahaEvent* event,
OmahaRequestParams* params,
bool ping_only,
bool include_ping,
int ping_active_days,
int ping_roll_call_days,
PrefsInterface* prefs) {
string app_body;
if (event == nullptr) {
if (include_ping)
app_body = GetPingXml(ping_active_days, ping_roll_call_days);
if (!ping_only) {
app_body += base::StringPrintf(
" <updatecheck targetversionprefix=\"%s\""
"></updatecheck>\n",
XmlEncodeWithDefault(params->target_version_prefix(), "").c_str());
// If this is the first update check after a reboot following a previous
// update, generate an event containing the previous version number. If
// the previous version preference file doesn't exist the event is still
// generated with a previous version of 0.0.0.0 -- this is relevant for
// older clients or new installs. The previous version event is not sent
// for ping-only requests because they come before the client has
// rebooted. The previous version event is also not sent if it was already
// sent for this new version with a previous updatecheck.
string prev_version;
if (!prefs->GetString(kPrefsPreviousVersion, &prev_version)) {
prev_version = "0.0.0.0";
}
// We only store a non-empty previous version value after a successful
// update in the previous boot. After reporting it back to the server,
// we clear the previous version value so it doesn't get reported again.
if (!prev_version.empty()) {
app_body += base::StringPrintf(
" <event eventtype=\"%d\" eventresult=\"%d\" "
"previousversion=\"%s\"></event>\n",
OmahaEvent::kTypeRebootedAfterUpdate,
OmahaEvent::kResultSuccess,
XmlEncodeWithDefault(prev_version, "0.0.0.0").c_str());
LOG_IF(WARNING, !prefs->SetString(kPrefsPreviousVersion, ""))
<< "Unable to reset the previous version.";
}
}
} else {
// The error code is an optional attribute so append it only if the result
// is not success.
string error_code;
if (event->result != OmahaEvent::kResultSuccess) {
error_code = base::StringPrintf(" errorcode=\"%d\"",
static_cast<int>(event->error_code));
}
app_body = base::StringPrintf(
" <event eventtype=\"%d\" eventresult=\"%d\"%s></event>\n",
event->type, event->result, error_code.c_str());
}
return app_body;
}
// Returns the cohort* argument to include in the <app> tag for the passed
// |arg_name| and |prefs_key|, if any. The return value is suitable to
// concatenate to the list of arguments and includes a space at the end.
string GetCohortArgXml(PrefsInterface* prefs,
const string arg_name,
const string prefs_key) {
// There's nothing wrong with not having a given cohort setting, so we check
// existance first to avoid the warning log message.
if (!prefs->Exists(prefs_key))
return "";
string cohort_value;
if (!prefs->GetString(prefs_key, &cohort_value) || cohort_value.empty())
return "";
// This is a sanity check to avoid sending a huge XML file back to Ohama due
// to a compromised stateful partition making the update check fail in low
// network environments envent after a reboot.
if (cohort_value.size() > 1024) {
LOG(WARNING) << "The omaha cohort setting " << arg_name
<< " has a too big value, which must be an error or an "
"attacker trying to inhibit updates.";
return "";
}
string escaped_xml_value;
if (!XmlEncode(cohort_value, &escaped_xml_value)) {
LOG(WARNING) << "The omaha cohort setting " << arg_name
<< " is ASCII-7 invalid, ignoring it.";
return "";
}
return base::StringPrintf("%s=\"%s\" ",
arg_name.c_str(), escaped_xml_value.c_str());
}
// Returns an XML that corresponds to the entire <app> node of the Omaha
// request based on the given parameters.
string GetAppXml(const OmahaEvent* event,
OmahaRequestParams* params,
bool ping_only,
bool include_ping,
int ping_active_days,
int ping_roll_call_days,
int install_date_in_days,
SystemState* system_state) {
string app_body = GetAppBody(event, params, ping_only, include_ping,
ping_active_days, ping_roll_call_days,
system_state->prefs());
string app_versions;
// If we are upgrading to a more stable channel and we are allowed to do
// powerwash, then pass 0.0.0.0 as the version. This is needed to get the
// highest-versioned payload on the destination channel.
if (params->to_more_stable_channel() && params->is_powerwash_allowed()) {
LOG(INFO) << "Passing OS version as 0.0.0.0 as we are set to powerwash "
<< "on downgrading to the version in the more stable channel";
app_versions = "version=\"0.0.0.0\" from_version=\"" +
XmlEncodeWithDefault(params->app_version(), "0.0.0.0") + "\" ";
} else {
app_versions = "version=\"" +
XmlEncodeWithDefault(params->app_version(), "0.0.0.0") + "\" ";
}
string download_channel = params->download_channel();
string app_channels =
"track=\"" + XmlEncodeWithDefault(download_channel, "") + "\" ";
if (params->current_channel() != download_channel) {
app_channels += "from_track=\"" + XmlEncodeWithDefault(
params->current_channel(), "") + "\" ";
}
string delta_okay_str = params->delta_okay() ? "true" : "false";
// If install_date_days is not set (e.g. its value is -1 ), don't
// include the attribute.
string install_date_in_days_str = "";
if (install_date_in_days >= 0) {
install_date_in_days_str = base::StringPrintf("installdate=\"%d\" ",
install_date_in_days);
}
string app_cohort_args;
app_cohort_args += GetCohortArgXml(system_state->prefs(),
"cohort", kPrefsOmahaCohort);
app_cohort_args += GetCohortArgXml(system_state->prefs(),
"cohorthint", kPrefsOmahaCohortHint);
app_cohort_args += GetCohortArgXml(system_state->prefs(),
"cohortname", kPrefsOmahaCohortName);
string app_xml = " <app "
"appid=\"" + XmlEncodeWithDefault(params->GetAppId(), "") + "\" " +
app_cohort_args +
app_versions +
app_channels +
"lang=\"" + XmlEncodeWithDefault(params->app_lang(), "en-US") + "\" " +
"board=\"" + XmlEncodeWithDefault(params->os_board(), "") + "\" " +
"hardware_class=\"" + XmlEncodeWithDefault(params->hwid(), "") + "\" " +
"delta_okay=\"" + delta_okay_str + "\" "
"fw_version=\"" + XmlEncodeWithDefault(params->fw_version(), "") + "\" " +
"ec_version=\"" + XmlEncodeWithDefault(params->ec_version(), "") + "\" " +
install_date_in_days_str +
">\n" +
app_body +
" </app>\n";
return app_xml;
}
// Returns an XML that corresponds to the entire <os> node of the Omaha
// request based on the given parameters.
string GetOsXml(OmahaRequestParams* params) {
string os_xml =" <os "
"version=\"" + XmlEncodeWithDefault(params->os_version(), "") + "\" " +
"platform=\"" + XmlEncodeWithDefault(params->os_platform(), "") + "\" " +
"sp=\"" + XmlEncodeWithDefault(params->os_sp(), "") + "\">"
"</os>\n";
return os_xml;
}
// Returns an XML that corresponds to the entire Omaha request based on the
// given parameters.
string GetRequestXml(const OmahaEvent* event,
OmahaRequestParams* params,
bool ping_only,
bool include_ping,
int ping_active_days,
int ping_roll_call_days,
int install_date_in_days,
SystemState* system_state) {
string os_xml = GetOsXml(params);
string app_xml = GetAppXml(event, params, ping_only, include_ping,
ping_active_days, ping_roll_call_days,
install_date_in_days, system_state);
string install_source = base::StringPrintf("installsource=\"%s\" ",
(params->interactive() ? "ondemandupdate" : "scheduler"));
string updater_version = XmlEncodeWithDefault(
base::StringPrintf("%s-%s",
constants::kOmahaUpdaterID,
kOmahaUpdaterVersion), "");
string request_xml =
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
"<request protocol=\"3.0\" " + (
"version=\"" + updater_version + "\" "
"updaterversion=\"" + updater_version + "\" " +
install_source +
"ismachine=\"1\">\n") +
os_xml +
app_xml +
"</request>\n";
return request_xml;
}
} // namespace
// Struct used for holding data obtained when parsing the XML.
struct OmahaParserData {
explicit OmahaParserData(XML_Parser _xml_parser) : xml_parser(_xml_parser) {}
// Pointer to the expat XML_Parser object.
XML_Parser xml_parser;
// This is the state of the parser as it's processing the XML.
bool failed = false;
bool entity_decl = false;
string current_path;
// These are the values extracted from the XML.
string app_cohort;
string app_cohorthint;
string app_cohortname;
bool app_cohort_set = false;
bool app_cohorthint_set = false;
bool app_cohortname_set = false;
string updatecheck_status;
string updatecheck_poll_interval;
string daystart_elapsed_days;
string daystart_elapsed_seconds;
vector<string> url_codebase;
string package_name;
string package_size;
string manifest_version;
map<string, string> action_postinstall_attrs;
};
namespace {
// Callback function invoked by expat.
void ParserHandlerStart(void* user_data, const XML_Char* element,
const XML_Char** attr) {
OmahaParserData* data = reinterpret_cast<OmahaParserData*>(user_data);
if (data->failed)
return;
data->current_path += string("/") + element;
map<string, string> attrs;
if (attr != nullptr) {
for (int n = 0; attr[n] != nullptr && attr[n+1] != nullptr; n += 2) {
string key = attr[n];
string value = attr[n + 1];
attrs[key] = value;
}
}
if (data->current_path == "/response/app") {
if (attrs.find("cohort") != attrs.end()) {
data->app_cohort_set = true;
data->app_cohort = attrs["cohort"];
}
if (attrs.find("cohorthint") != attrs.end()) {
data->app_cohorthint_set = true;
data->app_cohorthint = attrs["cohorthint"];
}
if (attrs.find("cohortname") != attrs.end()) {
data->app_cohortname_set = true;
data->app_cohortname = attrs["cohortname"];
}
} else if (data->current_path == "/response/app/updatecheck") {
// There is only supposed to be a single <updatecheck> element.
data->updatecheck_status = attrs["status"];
data->updatecheck_poll_interval = attrs["PollInterval"];
} else if (data->current_path == "/response/daystart") {
// Get the install-date.
data->daystart_elapsed_days = attrs["elapsed_days"];
data->daystart_elapsed_seconds = attrs["elapsed_seconds"];
} else if (data->current_path == "/response/app/updatecheck/urls/url") {
// Look at all <url> elements.
data->url_codebase.push_back(attrs["codebase"]);
} else if (data->package_name.empty() && data->current_path ==
"/response/app/updatecheck/manifest/packages/package") {
// Only look at the first <package>.
data->package_name = attrs["name"];
data->package_size = attrs["size"];
} else if (data->current_path == "/response/app/updatecheck/manifest") {
// Get the version.
data->manifest_version = attrs[kTagVersion];
} else if (data->current_path ==
"/response/app/updatecheck/manifest/actions/action") {
// We only care about the postinstall action.
if (attrs["event"] == "postinstall") {
data->action_postinstall_attrs = attrs;
}
}
}
// Callback function invoked by expat.
void ParserHandlerEnd(void* user_data, const XML_Char* element) {
OmahaParserData* data = reinterpret_cast<OmahaParserData*>(user_data);
if (data->failed)
return;
const string path_suffix = string("/") + element;
if (!base::EndsWith(data->current_path, path_suffix,
base::CompareCase::SENSITIVE)) {
LOG(ERROR) << "Unexpected end element '" << element
<< "' with current_path='" << data->current_path << "'";
data->failed = true;
return;
}
data->current_path.resize(data->current_path.size() - path_suffix.size());
}
// Callback function invoked by expat.
//
// This is called for entity declarations. Since Omaha is guaranteed
// to never return any XML with entities our course of action is to
// just stop parsing. This avoids potential resource exhaustion
// problems AKA the "billion laughs". CVE-2013-0340.
void ParserHandlerEntityDecl(void *user_data,
const XML_Char *entity_name,
int is_parameter_entity,
const XML_Char *value,
int value_length,
const XML_Char *base,
const XML_Char *system_id,
const XML_Char *public_id,
const XML_Char *notation_name) {
OmahaParserData* data = reinterpret_cast<OmahaParserData*>(user_data);
LOG(ERROR) << "XML entities are not supported. Aborting parsing.";
data->failed = true;
data->entity_decl = true;
XML_StopParser(data->xml_parser, false);
}
} // namespace
bool XmlEncode(const string& input, string* output) {
if (std::find_if(input.begin(), input.end(),
[](const char c){return c & 0x80;}) != input.end()) {
LOG(WARNING) << "Invalid ASCII-7 string passed to the XML encoder:";
utils::HexDumpString(input);
return false;
}
output->clear();
// We need at least input.size() space in the output, but the code below will
// handle it if we need more.
output->reserve(input.size());
for (char c : input) {
switch (c) {
case '\"':
output->append(""");
break;
case '\'':
output->append("'");
break;
case '&':
output->append("&");
break;
case '<':
output->append("<");
break;
case '>':
output->append(">");
break;
default:
output->push_back(c);
}
}
return true;
}
string XmlEncodeWithDefault(const string& input, const string& default_value) {
string output;
if (XmlEncode(input, &output))
return output;
return default_value;
}
OmahaRequestAction::OmahaRequestAction(
SystemState* system_state,
OmahaEvent* event,
std::unique_ptr<HttpFetcher> http_fetcher,
bool ping_only)
: system_state_(system_state),
event_(event),
http_fetcher_(std::move(http_fetcher)),
ping_only_(ping_only),
ping_active_days_(0),
ping_roll_call_days_(0) {
params_ = system_state->request_params();
}
OmahaRequestAction::~OmahaRequestAction() {}
// Calculates the value to use for the ping days parameter.
int OmahaRequestAction::CalculatePingDays(const string& key) {
int days = kNeverPinged;
int64_t last_ping = 0;
if (system_state_->prefs()->GetInt64(key, &last_ping) && last_ping >= 0) {
days = (Time::Now() - Time::FromInternalValue(last_ping)).InDays();
if (days < 0) {
// If |days| is negative, then the system clock must have jumped
// back in time since the ping was sent. Mark the value so that
// it doesn't get sent to the server but we still update the
// last ping daystart preference. This way the next ping time
// will be correct, hopefully.
days = kPingTimeJump;
LOG(WARNING) <<
"System clock jumped back in time. Resetting ping daystarts.";
}
}
return days;
}
void OmahaRequestAction::InitPingDays() {
// We send pings only along with update checks, not with events.
if (IsEvent()) {
return;
}
// TODO(petkov): Figure a way to distinguish active use pings
// vs. roll call pings. Currently, the two pings are identical. A
// fix needs to change this code as well as UpdateLastPingDays and ShouldPing.
ping_active_days_ = CalculatePingDays(kPrefsLastActivePingDay);
ping_roll_call_days_ = CalculatePingDays(kPrefsLastRollCallPingDay);
}
bool OmahaRequestAction::ShouldPing() const {
if (ping_active_days_ == OmahaRequestAction::kNeverPinged &&
ping_roll_call_days_ == OmahaRequestAction::kNeverPinged) {
int powerwash_count = system_state_->hardware()->GetPowerwashCount();
if (powerwash_count > 0) {
LOG(INFO) << "Not sending ping with a=-1 r=-1 to omaha because "
<< "powerwash_count is " << powerwash_count;
return false;
}
return true;
}
return ping_active_days_ > 0 || ping_roll_call_days_ > 0;
}
// static
int OmahaRequestAction::GetInstallDate(SystemState* system_state) {
PrefsInterface* prefs = system_state->prefs();
if (prefs == nullptr)
return -1;
// If we have the value stored on disk, just return it.
int64_t stored_value;
if (prefs->GetInt64(kPrefsInstallDateDays, &stored_value)) {
// Convert and sanity-check.
int install_date_days = static_cast<int>(stored_value);
if (install_date_days >= 0)
return install_date_days;
LOG(ERROR) << "Dropping stored Omaha InstallData since its value num_days="
<< install_date_days << " looks suspicious.";
prefs->Delete(kPrefsInstallDateDays);
}
// Otherwise, if OOBE is not complete then do nothing and wait for
// ParseResponse() to call ParseInstallDate() and then
// PersistInstallDate() to set the kPrefsInstallDateDays state
// variable. Once that is done, we'll then report back in future
// Omaha requests. This works exactly because OOBE triggers an
// update check.
//
// However, if OOBE is complete and the kPrefsInstallDateDays state
// variable is not set, there are two possibilities
//
// 1. The update check in OOBE failed so we never got a response
// from Omaha (no network etc.); or
//
// 2. OOBE was done on an older version that didn't write to the
// kPrefsInstallDateDays state variable.
//
// In both cases, we approximate the install date by simply
// inspecting the timestamp of when OOBE happened.
Time time_of_oobe;
if (!system_state->hardware()->IsOOBEComplete(&time_of_oobe)) {
LOG(INFO) << "Not generating Omaha InstallData as we have "
<< "no prefs file and OOBE is not complete.";
return -1;
}
int num_days;
if (!utils::ConvertToOmahaInstallDate(time_of_oobe, &num_days)) {
LOG(ERROR) << "Not generating Omaha InstallData from time of OOBE "
<< "as its value '" << utils::ToString(time_of_oobe)
<< "' looks suspicious.";
return -1;
}
// Persist this to disk, for future use.
if (!OmahaRequestAction::PersistInstallDate(system_state,
num_days,
kProvisionedFromOOBEMarker))
return -1;
LOG(INFO) << "Set the Omaha InstallDate from OOBE time-stamp to "
<< num_days << " days";
return num_days;
}
void OmahaRequestAction::PerformAction() {
http_fetcher_->set_delegate(this);
InitPingDays();
if (ping_only_ && !ShouldPing()) {
processor_->ActionComplete(this, ErrorCode::kSuccess);
return;
}
string request_post(GetRequestXml(event_.get(),
params_,
ping_only_,
ShouldPing(), // include_ping
ping_active_days_,
ping_roll_call_days_,
GetInstallDate(system_state_),
system_state_));
http_fetcher_->SetPostData(request_post.data(), request_post.size(),
kHttpContentTypeTextXml);
LOG(INFO) << "Posting an Omaha request to " << params_->update_url();
LOG(INFO) << "Request: " << request_post;
http_fetcher_->BeginTransfer(params_->update_url());
}
void OmahaRequestAction::TerminateProcessing() {
http_fetcher_->TerminateTransfer();
}
// We just store the response in the buffer. Once we've received all bytes,
// we'll look in the buffer and decide what to do.
void OmahaRequestAction::ReceivedBytes(HttpFetcher *fetcher,
const void* bytes,
size_t length) {
const uint8_t* byte_ptr = reinterpret_cast<const uint8_t*>(bytes);
response_buffer_.insert(response_buffer_.end(), byte_ptr, byte_ptr + length);
}
namespace {
// Parses a 64 bit base-10 int from a string and returns it. Returns 0
// on error. If the string contains "0", that's indistinguishable from
// error.
off_t ParseInt(const string& str) {
off_t ret = 0;
int rc = sscanf(str.c_str(), "%" PRIi64, &ret); // NOLINT(runtime/printf)
if (rc < 1) {
// failure
return 0;
}
return ret;
}
// Parses |str| and returns |true| if, and only if, its value is "true".
bool ParseBool(const string& str) {
return str == "true";
}
// Update the last ping day preferences based on the server daystart
// response. Returns true on success, false otherwise.
bool UpdateLastPingDays(OmahaParserData *parser_data, PrefsInterface* prefs) {
int64_t elapsed_seconds = 0;
TEST_AND_RETURN_FALSE(
base::StringToInt64(parser_data->daystart_elapsed_seconds,
&elapsed_seconds));
TEST_AND_RETURN_FALSE(elapsed_seconds >= 0);
// Remember the local time that matches the server's last midnight
// time.
Time daystart = Time::Now() - TimeDelta::FromSeconds(elapsed_seconds);
prefs->SetInt64(kPrefsLastActivePingDay, daystart.ToInternalValue());
prefs->SetInt64(kPrefsLastRollCallPingDay, daystart.ToInternalValue());
return true;
}
} // namespace
bool OmahaRequestAction::ParseResponse(OmahaParserData* parser_data,
OmahaResponse* output_object,
ScopedActionCompleter* completer) {
if (parser_data->updatecheck_status.empty()) {
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
// chromium-os:37289: The PollInterval is not supported by Omaha server
// currently. But still keeping this existing code in case we ever decide to
// slow down the request rate from the server-side. Note that the PollInterval
// is not persisted, so it has to be sent by the server on every response to
// guarantee that the scheduler uses this value (otherwise, if the device got
// rebooted after the last server-indicated value, it'll revert to the default
// value). Also kDefaultMaxUpdateChecks value for the scattering logic is
// based on the assumption that we perform an update check every hour so that
// the max value of 8 will roughly be equivalent to one work day. If we decide
// to use PollInterval permanently, we should update the
// max_update_checks_allowed to take PollInterval into account. Note: The
// parsing for PollInterval happens even before parsing of the status because
// we may want to specify the PollInterval even when there's no update.
base::StringToInt(parser_data->updatecheck_poll_interval,
&output_object->poll_interval);
// Check for the "elapsed_days" attribute in the "daystart"
// element. This is the number of days since Jan 1 2007, 0:00
// PST. If we don't have a persisted value of the Omaha InstallDate,
// we'll use it to calculate it and then persist it.
if (ParseInstallDate(parser_data, output_object) &&
!HasInstallDate(system_state_)) {
// Since output_object->install_date_days is never negative, the
// elapsed_days -> install-date calculation is reduced to simply
// rounding down to the nearest number divisible by 7.
int remainder = output_object->install_date_days % 7;
int install_date_days_rounded =
output_object->install_date_days - remainder;
if (PersistInstallDate(system_state_,
install_date_days_rounded,
kProvisionedFromOmahaResponse)) {
LOG(INFO) << "Set the Omaha InstallDate from Omaha Response to "
<< install_date_days_rounded << " days";
}
}
// We persist the cohorts sent by omaha even if the status is "noupdate".
if (parser_data->app_cohort_set)
PersistCohortData(kPrefsOmahaCohort, parser_data->app_cohort);
if (parser_data->app_cohorthint_set)
PersistCohortData(kPrefsOmahaCohortHint, parser_data->app_cohorthint);
if (parser_data->app_cohortname_set)
PersistCohortData(kPrefsOmahaCohortName, parser_data->app_cohortname);
if (!ParseStatus(parser_data, output_object, completer))
return false;
// Note: ParseUrls MUST be called before ParsePackage as ParsePackage
// appends the package name to the URLs populated in this method.
if (!ParseUrls(parser_data, output_object, completer))
return false;
if (!ParsePackage(parser_data, output_object, completer))
return false;
if (!ParseParams(parser_data, output_object, completer))
return false;
return true;
}
bool OmahaRequestAction::ParseStatus(OmahaParserData* parser_data,
OmahaResponse* output_object,
ScopedActionCompleter* completer) {
const string& status = parser_data->updatecheck_status;
if (status == "noupdate") {
LOG(INFO) << "No update.";
output_object->update_exists = false;
SetOutputObject(*output_object);
completer->set_code(ErrorCode::kSuccess);
return false;
}
if (status != "ok") {
LOG(ERROR) << "Unknown Omaha response status: " << status;
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
return true;
}
bool OmahaRequestAction::ParseUrls(OmahaParserData* parser_data,
OmahaResponse* output_object,
ScopedActionCompleter* completer) {
if (parser_data->url_codebase.empty()) {
LOG(ERROR) << "No Omaha Response URLs";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
LOG(INFO) << "Found " << parser_data->url_codebase.size() << " url(s)";
output_object->payload_urls.clear();
for (const auto& codebase : parser_data->url_codebase) {
if (codebase.empty()) {
LOG(ERROR) << "Omaha Response URL has empty codebase";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
output_object->payload_urls.push_back(codebase);
}
return true;
}
bool OmahaRequestAction::ParsePackage(OmahaParserData* parser_data,
OmahaResponse* output_object,
ScopedActionCompleter* completer) {
if (parser_data->package_name.empty()) {
LOG(ERROR) << "Omaha Response has empty package name";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
// Append the package name to each URL in our list so that we don't
// propagate the urlBase vs packageName distinctions beyond this point.
// From now on, we only need to use payload_urls.
for (auto& payload_url : output_object->payload_urls)
payload_url += parser_data->package_name;
// Parse the payload size.
off_t size = ParseInt(parser_data->package_size);
if (size <= 0) {
LOG(ERROR) << "Omaha Response has invalid payload size: " << size;
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
output_object->size = size;
LOG(INFO) << "Payload size = " << output_object->size << " bytes";
return true;
}
bool OmahaRequestAction::ParseParams(OmahaParserData* parser_data,
OmahaResponse* output_object,
ScopedActionCompleter* completer) {
output_object->version = parser_data->manifest_version;
if (output_object->version.empty()) {
LOG(ERROR) << "Omaha Response does not have version in manifest!";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
LOG(INFO) << "Received omaha response to update to version "
<< output_object->version;
map<string, string> attrs = parser_data->action_postinstall_attrs;
if (attrs.empty()) {
LOG(ERROR) << "Omaha Response has no postinstall event action";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
output_object->hash = attrs[kTagSha256];
if (output_object->hash.empty()) {
LOG(ERROR) << "Omaha Response has empty sha256 value";
completer->set_code(ErrorCode::kOmahaResponseInvalid);
return false;
}
// Get the optional properties one by one.
output_object->more_info_url = attrs[kTagMoreInfo];
output_object->metadata_size = ParseInt(attrs[kTagMetadataSize]);
output_object->metadata_signature = attrs[kTagMetadataSignatureRsa];
output_object->prompt = ParseBool(attrs[kTagPrompt]);
output_object->deadline = attrs[kTagDeadline];
output_object->max_days_to_scatter = ParseInt(attrs[kTagMaxDaysToScatter]);
output_object->disable_p2p_for_downloading =
ParseBool(attrs[kTagDisableP2PForDownloading]);
output_object->disable_p2p_for_sharing =
ParseBool(attrs[kTagDisableP2PForSharing]);
output_object->public_key_rsa = attrs[kTagPublicKeyRsa];
string max = attrs[kTagMaxFailureCountPerUrl];
if (!base::StringToUint(max, &output_object->max_failure_count_per_url))
output_object->max_failure_count_per_url = kDefaultMaxFailureCountPerUrl;
output_object->is_delta_payload = ParseBool(attrs[kTagIsDeltaPayload]);
output_object->disable_payload_backoff =
ParseBool(attrs[kTagDisablePayloadBackoff]);
return true;
}
// If the transfer was successful, this uses expat to parse the response
// and fill in the appropriate fields of the output object. Also, notifies
// the processor that we're done.
void OmahaRequestAction::TransferComplete(HttpFetcher *fetcher,
bool successful) {
ScopedActionCompleter completer(processor_, this);
string current_response(response_buffer_.begin(), response_buffer_.end());
LOG(INFO) << "Omaha request response: " << current_response;
PayloadStateInterface* const payload_state = system_state_->payload_state();
// Events are best effort transactions -- assume they always succeed.
if (IsEvent()) {
CHECK(!HasOutputPipe()) << "No output pipe allowed for event requests.";
if (event_->result == OmahaEvent::kResultError && successful &&
system_state_->hardware()->IsOfficialBuild()) {
LOG(INFO) << "Signalling Crash Reporter.";
utils::ScheduleCrashReporterUpload();
}
completer.set_code(ErrorCode::kSuccess);
return;
}
if (!successful) {
LOG(ERROR) << "Omaha request network transfer failed.";
int code = GetHTTPResponseCode();
// Makes sure we send sane error values.
if (code < 0 || code >= 1000) {
code = 999;
}
completer.set_code(static_cast<ErrorCode>(
static_cast<int>(ErrorCode::kOmahaRequestHTTPResponseBase) + code));
return;
}
XML_Parser parser = XML_ParserCreate(nullptr);
OmahaParserData parser_data(parser);
XML_SetUserData(parser, &parser_data);
XML_SetElementHandler(parser, ParserHandlerStart, ParserHandlerEnd);
XML_SetEntityDeclHandler(parser, ParserHandlerEntityDecl);
XML_Status res = XML_Parse(
parser,
reinterpret_cast<const char*>(response_buffer_.data()),
response_buffer_.size(),
XML_TRUE);
XML_ParserFree(parser);
if (res != XML_STATUS_OK || parser_data.failed) {
LOG(ERROR) << "Omaha response not valid XML: "
<< XML_ErrorString(XML_GetErrorCode(parser))
<< " at line " << XML_GetCurrentLineNumber(parser)
<< " col " << XML_GetCurrentColumnNumber(parser);
ErrorCode error_code = ErrorCode::kOmahaRequestXMLParseError;
if (response_buffer_.empty()) {
error_code = ErrorCode::kOmahaRequestEmptyResponseError;
} else if (parser_data.entity_decl) {
error_code = ErrorCode::kOmahaRequestXMLHasEntityDecl;
}
completer.set_code(error_code);
return;
}
// Update the last ping day preferences based on the server daystart response
// even if we didn't send a ping. Omaha always includes the daystart in the
// response, but log the error if it didn't.
LOG_IF(ERROR, !UpdateLastPingDays(&parser_data, system_state_->prefs()))
<< "Failed to update the last ping day preferences!";
if (!HasOutputPipe()) {
// Just set success to whether or not the http transfer succeeded,
// which must be true at this point in the code.
completer.set_code(ErrorCode::kSuccess);
return;
}
OmahaResponse output_object;
if (!ParseResponse(&parser_data, &output_object, &completer))
return;
output_object.update_exists = true;
SetOutputObject(output_object);
if (ShouldIgnoreUpdate(output_object)) {
output_object.update_exists = false;
completer.set_code(ErrorCode::kOmahaUpdateIgnoredPerPolicy);
return;
}
// If Omaha says to disable p2p, respect that
if (output_object.disable_p2p_for_downloading) {
LOG(INFO) << "Forcibly disabling use of p2p for downloading as "
<< "requested by Omaha.";
payload_state->SetUsingP2PForDownloading(false);
}
if (output_object.disable_p2p_for_sharing) {
LOG(INFO) << "Forcibly disabling use of p2p for sharing as "
<< "requested by Omaha.";
payload_state->SetUsingP2PForSharing(false);
}
// Update the payload state with the current response. The payload state
// will automatically reset all stale state if this response is different
// from what's stored already. We are updating the payload state as late
// as possible in this method so that if a new release gets pushed and then
// got pulled back due to some issues, we don't want to clear our internal
// state unnecessarily.
payload_state->SetResponse(output_object);
// It could be we've already exceeded the deadline for when p2p is
// allowed or that we've tried too many times with p2p. Check that.
if (payload_state->GetUsingP2PForDownloading()) {
payload_state->P2PNewAttempt();
if (!payload_state->P2PAttemptAllowed()) {
LOG(INFO) << "Forcibly disabling use of p2p for downloading because "
<< "of previous failures when using p2p.";
payload_state->SetUsingP2PForDownloading(false);
}
}
// From here on, we'll complete stuff in CompleteProcessing() so
// disable |completer| since we'll create a new one in that
// function.
completer.set_should_complete(false);
// If we're allowed to use p2p for downloading we do not pay
// attention to wall-clock-based waiting if the URL is indeed
// available via p2p. Therefore, check if the file is available via
// p2p before deferring...
if (payload_state->GetUsingP2PForDownloading()) {
LookupPayloadViaP2P(output_object);
} else {
CompleteProcessing();
}
}
void OmahaRequestAction::CompleteProcessing() {
ScopedActionCompleter completer(processor_, this);
OmahaResponse& output_object = const_cast<OmahaResponse&>(GetOutputObject());
PayloadStateInterface* payload_state = system_state_->payload_state();
if (ShouldDeferDownload(&output_object)) {
output_object.update_exists = false;
LOG(INFO) << "Ignoring Omaha updates as updates are deferred by policy.";
completer.set_code(ErrorCode::kOmahaUpdateDeferredPerPolicy);
return;
}
if (payload_state->ShouldBackoffDownload()) {
output_object.update_exists = false;
LOG(INFO) << "Ignoring Omaha updates in order to backoff our retry "
<< "attempts";
completer.set_code(ErrorCode::kOmahaUpdateDeferredForBackoff);
return;
}
completer.set_code(ErrorCode::kSuccess);
}
void OmahaRequestAction::OnLookupPayloadViaP2PCompleted(const string& url) {
LOG(INFO) << "Lookup complete, p2p-client returned URL '" << url << "'";
if (!url.empty()) {
system_state_->payload_state()->SetP2PUrl(url);
} else {
LOG(INFO) << "Forcibly disabling use of p2p for downloading "
<< "because no suitable peer could be found.";
system_state_->payload_state()->SetUsingP2PForDownloading(false);
}
CompleteProcessing();
}
void OmahaRequestAction::LookupPayloadViaP2P(const OmahaResponse& response) {
// If the device is in the middle of an update, the state variables
// kPrefsUpdateStateNextDataOffset, kPrefsUpdateStateNextDataLength
// tracks the offset and length of the operation currently in
// progress. The offset is based from the end of the manifest which
// is kPrefsManifestMetadataSize bytes long.
//
// To make forward progress and avoid deadlocks, we need to find a
// peer that has at least the entire operation we're currently
// working on. Otherwise we may end up in a situation where two
// devices bounce back and forth downloading from each other,
// neither making any forward progress until one of them decides to
// stop using p2p (via kMaxP2PAttempts and kMaxP2PAttemptTimeSeconds
// safe-guards). See http://crbug.com/297170 for an example)
size_t minimum_size = 0;
int64_t manifest_metadata_size = 0;
int64_t manifest_signature_size = 0;
int64_t next_data_offset = 0;
int64_t next_data_length = 0;
if (system_state_ &&
system_state_->prefs()->GetInt64(kPrefsManifestMetadataSize,
&manifest_metadata_size) &&
manifest_metadata_size != -1 &&
system_state_->prefs()->GetInt64(kPrefsManifestSignatureSize,
&manifest_signature_size) &&
manifest_signature_size != -1 &&
system_state_->prefs()->GetInt64(kPrefsUpdateStateNextDataOffset,
&next_data_offset) &&
next_data_offset != -1 &&
system_state_->prefs()->GetInt64(kPrefsUpdateStateNextDataLength,
&next_data_length)) {
minimum_size = manifest_metadata_size + manifest_signature_size +
next_data_offset + next_data_length;
}
string file_id = utils::CalculateP2PFileId(response.hash, response.size);
if (system_state_->p2p_manager()) {
LOG(INFO) << "Checking if payload is available via p2p, file_id="
<< file_id << " minimum_size=" << minimum_size;
system_state_->p2p_manager()->LookupUrlForFile(
file_id,
minimum_size,
TimeDelta::FromSeconds(kMaxP2PNetworkWaitTimeSeconds),
base::Bind(&OmahaRequestAction::OnLookupPayloadViaP2PCompleted,
base::Unretained(this)));
}
}
bool OmahaRequestAction::ShouldDeferDownload(OmahaResponse* output_object) {
if (params_->interactive()) {
LOG(INFO) << "Not deferring download because update is interactive.";
return false;
}
// If we're using p2p to download _and_ we have a p2p URL, we never
// defer the download. This is because the download will always
// happen from a peer on the LAN and we've been waiting in line for
// our turn.
const PayloadStateInterface* payload_state = system_state_->payload_state();
if (payload_state->GetUsingP2PForDownloading() &&
!payload_state->GetP2PUrl().empty()) {
LOG(INFO) << "Download not deferred because download "
<< "will happen from a local peer (via p2p).";
return false;
}
// We should defer the downloads only if we've first satisfied the
// wall-clock-based-waiting period and then the update-check-based waiting
// period, if required.
if (!params_->wall_clock_based_wait_enabled()) {
LOG(INFO) << "Wall-clock-based waiting period is not enabled,"
<< " so no deferring needed.";
return false;
}
switch (IsWallClockBasedWaitingSatisfied(output_object)) {
case kWallClockWaitNotSatisfied:
// We haven't even satisfied the first condition, passing the
// wall-clock-based waiting period, so we should defer the downloads
// until that happens.
LOG(INFO) << "wall-clock-based-wait not satisfied.";
return true;
case kWallClockWaitDoneButUpdateCheckWaitRequired:
LOG(INFO) << "wall-clock-based-wait satisfied and "
<< "update-check-based-wait required.";
return !IsUpdateCheckCountBasedWaitingSatisfied();
case kWallClockWaitDoneAndUpdateCheckWaitNotRequired:
// Wall-clock-based waiting period is satisfied, and it's determined
// that we do not need the update-check-based wait. so no need to
// defer downloads.
LOG(INFO) << "wall-clock-based-wait satisfied and "
<< "update-check-based-wait is not required.";
return false;
default:
// Returning false for this default case so we err on the
// side of downloading updates than deferring in case of any bugs.
NOTREACHED();
return false;
}
}
OmahaRequestAction::WallClockWaitResult
OmahaRequestAction::IsWallClockBasedWaitingSatisfied(
OmahaResponse* output_object) {
Time update_first_seen_at;
int64_t update_first_seen_at_int;
if (system_state_->prefs()->Exists(kPrefsUpdateFirstSeenAt)) {
if (system_state_->prefs()->GetInt64(kPrefsUpdateFirstSeenAt,
&update_first_seen_at_int)) {
// Note: This timestamp could be that of ANY update we saw in the past
// (not necessarily this particular update we're considering to apply)
// but never got to apply because of some reason (e.g. stop AU policy,
// updates being pulled out from Omaha, changes in target version prefix,
// new update being rolled out, etc.). But for the purposes of scattering
// it doesn't matter which update the timestamp corresponds to. i.e.
// the clock starts ticking the first time we see an update and we're
// ready to apply when the random wait period is satisfied relative to
// that first seen timestamp.
update_first_seen_at = Time::FromInternalValue(update_first_seen_at_int);
LOG(INFO) << "Using persisted value of UpdateFirstSeenAt: "
<< utils::ToString(update_first_seen_at);
} else {
// This seems like an unexpected error where the persisted value exists
// but it's not readable for some reason. Just skip scattering in this
// case to be safe.
LOG(INFO) << "Not scattering as UpdateFirstSeenAt value cannot be read";
return kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
} else {
update_first_seen_at = Time::Now();
update_first_seen_at_int = update_first_seen_at.ToInternalValue();
if (system_state_->prefs()->SetInt64(kPrefsUpdateFirstSeenAt,
update_first_seen_at_int)) {
LOG(INFO) << "Persisted the new value for UpdateFirstSeenAt: "
<< utils::ToString(update_first_seen_at);
} else {
// This seems like an unexpected error where the value cannot be
// persisted for some reason. Just skip scattering in this
// case to be safe.
LOG(INFO) << "Not scattering as UpdateFirstSeenAt value "
<< utils::ToString(update_first_seen_at)
<< " cannot be persisted";
return kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
}
TimeDelta elapsed_time = Time::Now() - update_first_seen_at;
TimeDelta max_scatter_period = TimeDelta::FromDays(
output_object->max_days_to_scatter);
LOG(INFO) << "Waiting Period = "
<< utils::FormatSecs(params_->waiting_period().InSeconds())
<< ", Time Elapsed = "
<< utils::FormatSecs(elapsed_time.InSeconds())
<< ", MaxDaysToScatter = "
<< max_scatter_period.InDays();
if (!output_object->deadline.empty()) {
// The deadline is set for all rules which serve a delta update from a
// previous FSI, which means this update will be applied mostly in OOBE
// cases. For these cases, we shouldn't scatter so as to finish the OOBE
// quickly.
LOG(INFO) << "Not scattering as deadline flag is set";
return kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
if (max_scatter_period.InDays() == 0) {
// This means the Omaha rule creator decides that this rule
// should not be scattered irrespective of the policy.
LOG(INFO) << "Not scattering as MaxDaysToScatter in rule is 0.";
return kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
if (elapsed_time > max_scatter_period) {
// This means we've waited more than the upperbound wait in the rule
// from the time we first saw a valid update available to us.
// This will prevent update starvation.
LOG(INFO) << "Not scattering as we're past the MaxDaysToScatter limit.";
return kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
// This means we are required to participate in scattering.
// See if our turn has arrived now.
TimeDelta remaining_wait_time = params_->waiting_period() - elapsed_time;
if (remaining_wait_time.InSeconds() <= 0) {
// Yes, it's our turn now.
LOG(INFO) << "Successfully passed the wall-clock-based-wait.";
// But we can't download until the update-check-count-based wait is also
// satisfied, so mark it as required now if update checks are enabled.
return params_->update_check_count_wait_enabled() ?
kWallClockWaitDoneButUpdateCheckWaitRequired :
kWallClockWaitDoneAndUpdateCheckWaitNotRequired;
}
// Not our turn yet, so we have to wait until our turn to
// help scatter the downloads across all clients of the enterprise.
LOG(INFO) << "Update deferred for another "
<< utils::FormatSecs(remaining_wait_time.InSeconds())
<< " per policy.";
return kWallClockWaitNotSatisfied;
}
bool OmahaRequestAction::IsUpdateCheckCountBasedWaitingSatisfied() {
int64_t update_check_count_value;
if (system_state_->prefs()->Exists(kPrefsUpdateCheckCount)) {
if (!system_state_->prefs()->GetInt64(kPrefsUpdateCheckCount,
&update_check_count_value)) {
// We are unable to read the update check count from file for some reason.
// So let's proceed anyway so as to not stall the update.
LOG(ERROR) << "Unable to read update check count. "
<< "Skipping update-check-count-based-wait.";
return true;
}
} else {
// This file does not exist. This means we haven't started our update
// check count down yet, so this is the right time to start the count down.
update_check_count_value = base::RandInt(
params_->min_update_checks_needed(),
params_->max_update_checks_allowed());
LOG(INFO) << "Randomly picked update check count value = "
<< update_check_count_value;
// Write out the initial value of update_check_count_value.
if (!system_state_->prefs()->SetInt64(kPrefsUpdateCheckCount,
update_check_count_value)) {
// We weren't able to write the update check count file for some reason.
// So let's proceed anyway so as to not stall the update.
LOG(ERROR) << "Unable to write update check count. "
<< "Skipping update-check-count-based-wait.";
return true;
}
}
if (update_check_count_value == 0) {
LOG(INFO) << "Successfully passed the update-check-based-wait.";
return true;
}
if (update_check_count_value < 0 ||
update_check_count_value > params_->max_update_checks_allowed()) {
// We err on the side of skipping scattering logic instead of stalling
// a machine from receiving any updates in case of any unexpected state.
LOG(ERROR) << "Invalid value for update check count detected. "
<< "Skipping update-check-count-based-wait.";
return true;
}
// Legal value, we need to wait for more update checks to happen
// until this becomes 0.
LOG(INFO) << "Deferring Omaha updates for another "
<< update_check_count_value
<< " update checks per policy";
return false;
}
// static
bool OmahaRequestAction::ParseInstallDate(OmahaParserData* parser_data,
OmahaResponse* output_object) {
int64_t elapsed_days = 0;
if (!base::StringToInt64(parser_data->daystart_elapsed_days,
&elapsed_days))
return false;
if (elapsed_days < 0)
return false;
output_object->install_date_days = elapsed_days;
return true;
}
// static
bool OmahaRequestAction::HasInstallDate(SystemState *system_state) {
PrefsInterface* prefs = system_state->prefs();
if (prefs == nullptr)
return false;
return prefs->Exists(kPrefsInstallDateDays);
}
// static
bool OmahaRequestAction::PersistInstallDate(
SystemState *system_state,
int install_date_days,
InstallDateProvisioningSource source) {
TEST_AND_RETURN_FALSE(install_date_days >= 0);
PrefsInterface* prefs = system_state->prefs();
if (prefs == nullptr)
return false;
if (!prefs->SetInt64(kPrefsInstallDateDays, install_date_days))
return false;
string metric_name = metrics::kMetricInstallDateProvisioningSource;
system_state->metrics_lib()->SendEnumToUMA(
metric_name,
static_cast<int>(source), // Sample.
kProvisionedMax); // Maximum.
return true;
}
bool OmahaRequestAction::PersistCohortData(
const string& prefs_key,
const string& new_value) {
if (new_value.empty() && system_state_->prefs()->Exists(prefs_key)) {
LOG(INFO) << "Removing stored " << prefs_key << " value.";
return system_state_->prefs()->Delete(prefs_key);
} else if (!new_value.empty()) {
LOG(INFO) << "Storing new setting " << prefs_key << " as " << new_value;
return system_state_->prefs()->SetString(prefs_key, new_value);
}
return true;
}
void OmahaRequestAction::ActionCompleted(ErrorCode code) {
// We only want to report this on "update check".
if (ping_only_ || event_ != nullptr)
return;
metrics::CheckResult result = metrics::CheckResult::kUnset;
metrics::CheckReaction reaction = metrics::CheckReaction::kUnset;
metrics::DownloadErrorCode download_error_code =
metrics::DownloadErrorCode::kUnset;
// Regular update attempt.
switch (code) {
case ErrorCode::kSuccess:
// OK, we parsed the response successfully but that does
// necessarily mean that an update is available.
if (HasOutputPipe()) {
const OmahaResponse& response = GetOutputObject();
if (response.update_exists) {
result = metrics::CheckResult::kUpdateAvailable;
reaction = metrics::CheckReaction::kUpdating;
} else {
result = metrics::CheckResult::kNoUpdateAvailable;
}
} else {
result = metrics::CheckResult::kNoUpdateAvailable;
}
break;
case ErrorCode::kOmahaUpdateIgnoredPerPolicy:
result = metrics::CheckResult::kUpdateAvailable;
reaction = metrics::CheckReaction::kIgnored;
break;
case ErrorCode::kOmahaUpdateDeferredPerPolicy:
result = metrics::CheckResult::kUpdateAvailable;
reaction = metrics::CheckReaction::kDeferring;
break;
case ErrorCode::kOmahaUpdateDeferredForBackoff:
result = metrics::CheckResult::kUpdateAvailable;
reaction = metrics::CheckReaction::kBackingOff;
break;
default:
// We report two flavors of errors, "Download errors" and "Parsing
// error". Try to convert to the former and if that doesn't work
// we know it's the latter.
metrics::DownloadErrorCode tmp_error =
metrics_utils::GetDownloadErrorCode(code);
if (tmp_error != metrics::DownloadErrorCode::kInputMalformed) {
result = metrics::CheckResult::kDownloadError;
download_error_code = tmp_error;
} else {
result = metrics::CheckResult::kParsingError;
}
break;
}
metrics::ReportUpdateCheckMetrics(system_state_,
result, reaction, download_error_code);
}
bool OmahaRequestAction::ShouldIgnoreUpdate(
const OmahaResponse& response) const {
// Note: policy decision to not update to a version we rolled back from.
string rollback_version =
system_state_->payload_state()->GetRollbackVersion();
if (!rollback_version.empty()) {
LOG(INFO) << "Detected previous rollback from version " << rollback_version;
if (rollback_version == response.version) {
LOG(INFO) << "Received version that we rolled back from. Ignoring.";
return true;
}
}
if (!IsUpdateAllowedOverCurrentConnection()) {
LOG(INFO) << "Update is not allowed over current connection.";
return true;
}
// Note: We could technically delete the UpdateFirstSeenAt state when we
// return true. If we do, it'll mean a device has to restart the
// UpdateFirstSeenAt and thus help scattering take effect when the AU is
// turned on again. On the other hand, it also increases the chance of update
// starvation if an admin turns AU on/off more frequently. We choose to err on
// the side of preventing starvation at the cost of not applying scattering in
// those cases.
return false;
}
bool OmahaRequestAction::IsUpdateAllowedOverCurrentConnection() const {
NetworkConnectionType type;
NetworkTethering tethering;
ConnectionManagerInterface* connection_manager =
system_state_->connection_manager();
if (!connection_manager->GetConnectionProperties(&type, &tethering)) {
LOG(INFO) << "We could not determine our connection type. "
<< "Defaulting to allow updates.";
return true;
}
bool is_allowed = connection_manager->IsUpdateAllowedOver(type, tethering);
LOG(INFO) << "We are connected via "
<< ConnectionManager::StringForConnectionType(type)
<< ", Updates allowed: " << (is_allowed ? "Yes" : "No");
return is_allowed;
}
} // namespace chromeos_update_engine