commit ba51c3f54c88170d562c6e3af3f4820ee47aeb68
author Marton Hunyady <hunyadym@chromium.org> Wed Apr 25 15:18:10 2018 +0200
committer chrome-bot <chrome-bot@chromium.org> Thu May 10 15:09:45 2018 -0700
tree 675f4e16eb2ad9783ffa305e24fc17890facd7b0
parent 99ced78e2e5d6ad70c6cd274300f42b9a56a65b1

update_engine: Add rollback_allowed policy in Omaha requests

Send rollback_allowed="true" parameter to Omaha if rollback is
allowed through enterprise policy.

This parameter indicates to Omaha that the returned image might
be a rollback image, if the targetversionprefix parameter is set
and it is an earlier version than the one which is currently on
the device.

Also, this CL changes update_engine behavior to only send
targetversionprefix to Omaha if it's not empty.

BUG=chromium:814830
TEST='cros_run_unit_tests --board=cyan --packages update_engine'

Change-Id: Iaa5503e217631311fb9ba3a5237ccbfedf04afe9
Reviewed-on: https://chromium-review.googlesource.com/932123
Commit-Ready: Marton Hunyady <hunyadym@chromium.org>
Tested-by: Marton Hunyady <hunyadym@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>

update_attempter.cc

diff --git a/update_attempter.cc b/update_attempter.cc
index 10118ac..9d18932 100644
--- a/update_attempter.cc
+++ b/update_attempter.cc
@@ -241,6 +241,7 @@
                              const string& omaha_url,
                              const string& target_channel,
                              const string& target_version_prefix,
+                             bool rollback_allowed,
                              bool obey_proxies,
                              bool interactive) {
   // This is normally called frequently enough so it's appropriate to use as a
@@ -279,6 +280,7 @@
                              omaha_url,
                              target_channel,
                              target_version_prefix,
+                             rollback_allowed,
                              obey_proxies,
                              interactive)) {
     return;
@@ -354,6 +356,7 @@
                                             const string& omaha_url,
                                             const string& target_channel,
                                             const string& target_version_prefix,
+                                            bool rollback_allowed,
                                             bool obey_proxies,
                                             bool interactive) {
   http_response_code_ = 0;
@@ -369,6 +372,9 @@
   // Update the target version prefix.
   omaha_request_params_->set_target_version_prefix(target_version_prefix);
 
+  // Set whether rollback is allowed.
+  omaha_request_params_->set_rollback_allowed(rollback_allowed);
+
   CalculateScatteringParams(interactive);
 
   CalculateP2PParams(interactive);
@@ -414,6 +420,8 @@
 
   LOG(INFO) << "target_version_prefix = "
             << omaha_request_params_->target_version_prefix()
+            << ", rollback_allowed = "
+            << omaha_request_params_->rollback_allowed()
             << ", scatter_factor_in_seconds = "
             << utils::FormatSecs(scatter_factor_.InSeconds());
 
@@ -885,8 +893,13 @@
     LOG(INFO) << "Update attempt flags in use = 0x" << std::hex
               << current_update_attempt_flags_;
 
-    Update(forced_app_version_, forced_omaha_url_, params.target_channel,
-           params.target_version_prefix, false, params.is_interactive);
+    Update(forced_app_version_,
+           forced_omaha_url_,
+           params.target_channel,
+           params.target_version_prefix,
+           params.rollback_allowed,
+           /*obey_proxies=*/false,
+           params.is_interactive);
     // Always clear the forced app_version and omaha_url after an update attempt
     // so the next update uses the defaults.
     forced_app_version_.clear();