From a1c4e0ec5deaf3c6c4e8694afd67eb5a24bd0fa5 Mon Sep 17 00:00:00 2001
From: Janis Danisevskis <jdanis@google.com>
Date: Tue, 19 Jun 2018 19:08:15 -0700
Subject: [PATCH] Relax HMAC computation check

This KM4 key agreement check is causing some pain on early units
that aren't completely provisioned in both locked and non-Green
(unlocked) states.

This doesn't impact KM3 devices (Pixel 2016/2017 etc.)

Bug: 110301629
Change-Id: I5a737ac8a335863b1099c29cf3c0496adeb41e15
---
 keymaster/4.0/support/Keymaster.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/keymaster/4.0/support/Keymaster.cpp b/keymaster/4.0/support/Keymaster.cpp
index 444298b5bb..9325cc0699 100644
--- a/keymaster/4.0/support/Keymaster.cpp
+++ b/keymaster/4.0/support/Keymaster.cpp
@@ -164,10 +164,10 @@ static void computeHmac(const Keymaster::KeymasterSet& keymasters,
                     sharingCheck = curSharingCheck;
                     firstKeymaster = false;
                 }
-                CHECK(curSharingCheck == sharingCheck)
-                    << "HMAC computation failed for " << *keymaster  //
-                    << " Expected: " << sharingCheck                 //
-                    << " got: " << curSharingCheck;
+                if (curSharingCheck != sharingCheck)
+                    LOG(WARNING) << "HMAC computation failed for " << *keymaster  //
+                                 << " Expected: " << sharingCheck                 //
+                                 << " got: " << curSharingCheck;
             });
         CHECK(rc.isOk()) << "Failed to communicate with " << *keymaster
                          << " error: " << rc.description();