commit 2807536fc4415e65b1c7950f7fb0f93ce1777292
author Shawn Willden <swillden@google.com> Wed May 09 08:12:10 2018 -0600
committer Shawn Willden <swillden@google.com> Wed May 09 15:14:34 2018 -0600
tree ce117f05e7dde8beaad947468735e5751d27a13a
parent 4a04cad4ec65dc9e069809e1756242e63ab18ff5

Do Keymaster HMAC key agreement in vold.

Bug: 79307225
Test: Boot
Change-Id: I6682e86076aa568907d94024ef175dbdede86557

Keymaster.cpp

diff --git a/Keymaster.cpp b/Keymaster.cpp
index 7df27ec..4921448 100644
--- a/Keymaster.cpp
+++ b/Keymaster.cpp
@@ -96,8 +96,14 @@
     return true;
 }
 
+/* static */ bool Keymaster::hmacKeyGenerated = false;
+
 Keymaster::Keymaster() {
     auto devices = KmDevice::enumerateAvailableDevices();
+    if (!hmacKeyGenerated) {
+        KmDevice::performHmacKeyAgreement(devices);
+        hmacKeyGenerated = true;
+    }
     for (auto& dev : devices) {
         // Explicitly avoid using STRONGBOX for now.
         // TODO: Re-enable STRONGBOX, since it's what we really want. b/77338527

Keymaster.h

diff --git a/Keymaster.h b/Keymaster.h
index 7571402..fabe0f4 100644
--- a/Keymaster.h
+++ b/Keymaster.h
@@ -117,6 +117,7 @@
   private:
     std::unique_ptr<KmDevice> mDevice;
     DISALLOW_COPY_AND_ASSIGN(Keymaster);
+    static bool hmacKeyGenerated;
 };
 
 }  // namespace vold