ECDH encryption module
Add a module for encrypting using ECDH, HKDF, and AES-GCM.
Also, add serialization of EC private keys, and remove derivation
from secrets; it turns out this is a better fit for the way
superencryption currently works.
Add a more thorough ECDH test in the crypto module, which simulates an
ephemeral key being used to send a message to a long-term key. The
high-level module has a similar test.
Bug: 163866361
Test: keystore2_crypto_test_rust, keystore2_test
Change-Id: I4c2bb1d8938de078ea37b930619918acc3c28fbe
diff --git a/keystore2/src/lib.rs b/keystore2/src/lib.rs
index cb47e3e..b6df8e8 100644
--- a/keystore2/src/lib.rs
+++ b/keystore2/src/lib.rs
@@ -19,6 +19,7 @@
pub mod async_task;
pub mod authorization;
pub mod database;
+pub mod ec_crypto;
pub mod enforcements;
pub mod entropy;
pub mod error;