Rewrite key management & signing
Extend compos_helper to support signing, use it from CompOS.
Expose the public key from the VM. Rename compos_verify_key to
compos_verify and get it to verify the signature against the current
instance's public key.
Also move DICE access to compos_key_main. There's no use having it in
the library - neither the tests nor compos_verify can use it - and it
complicates the build rules.
There's a lot more that can be deleted, but I'll do that in a
follow-up; this is big enough already.
Bug: 218494522
Test: atest CompOsSigningHostTest CompOsDenialHostTest
Change-Id: I2d71f68a595d5ddadb2e7b16937fa6855f5db0ab
diff --git a/compos/verify/native/lib.rs b/compos/verify/native/lib.rs
new file mode 100644
index 0000000..51050da
--- /dev/null
+++ b/compos/verify/native/lib.rs
@@ -0,0 +1,31 @@
+// Copyright 2022, 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.
+
+//! Native helper for compos_verify to call boringssl.
+
+pub use native::*;
+
+#[cxx::bridge]
+mod native {
+ unsafe extern "C++" {
+ include!("verify_native.h");
+
+ // SAFETY: The C++ implementation manages its own memory, and does not retain or abuse
+ // the references passed to it.
+
+ /// Verify a PureEd25519 signature with the specified public key on the given data,
+ /// returning whether the signature is valid or not.
+ fn verify(public_key: &[u8], signature: &[u8], data: &[u8]) -> bool;
+ }
+}