Test remote attestation in UEFI app

.github/workflows/ci.yaml

@@ -64,7 +64,7 @@ jobs:
         uses: actions/cache@v2
         env:
           # Increment this value to invalidate previous cache entries.
-          CACHE_VERSION: 3
+          CACHE_VERSION: 4
         with:
           path: |
             ./cargo-cache/bin

experimental/uefi/app/.cargo/config.toml

@@ -2,7 +2,7 @@
 target = "x86_64-unknown-uefi"
 
 [target.x86_64-unknown-uefi]
-runner = "qemu-system-x86_64 -nodefaults -nographic -bios /usr/share/OVMF/OVMF_CODE.fd -serial file:target/console.log -serial stdio -machine q35 -device isa-debug-exit,iobase=0xf4,iosize=0x04 -kernel"
+runner = "./runner"
 
 [unstable]
 build-std = ["core", "alloc"]

experimental/uefi/app/Cargo.toml

@@ -5,6 +5,10 @@ authors = ["Andri Saar <[email protected]>"]
 edition = "2021"
 license = "Apache-2.0"
 
+[features]
+default = ["support_emulated_runner"]
+support_emulated_runner = []
+
 [dependencies]
 uefi = { version = "*", features = ["exts"] }
 uefi-services = "*"
@@ -14,4 +18,5 @@ ciborium-io = "*"
 oak_remote_attestation = { path = "../../../remote_attestation/rust" }
 
 [dev-dependencies]
+anyhow = { version = "*", default-features = false }
 uefi-services = { version = "*", features = ["qemu"] }

experimental/uefi/app/runner

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+
+# Thin shell script invoked as a cargo runner to run the compiled efi firmware
+# in QEMU. Detects if kvm is supported, and sets qemu flags based on that.
+# Instead of this single runner script it would be preferable to use a different
+# runner based on whether the kvm feature is set. However, cargo does not
+# currently allow this. Ref: https://github.com/rust-lang/cargo/issues/8170
+
+readonly TARGET=$1
+
+qemu_flags=(
+  '-nodefaults'
+  '-nographic'
+  '-bios' '/usr/share/OVMF/OVMF_CODE.fd'
+  '-serial' 'file:target/console.log'
+  '-serial' 'stdio'
+  '-machine' 'q35'
+  '-device' 'isa-debug-exit,iobase=0xf4,iosize=0x04'
+)
+
+# Use kvm if supported, as it is required for certain features. Note
+# that hosts that support kvm still need to disable the default
+# `support_emulated_runner` feature in cargo to include code that requires kvm
+# in the compiled firmware. Ideally this check would rely on the cargo
+# flag itself, enabling kvm if it is disabled. However cargo does not expose
+# which flags are set to the runner. Ref: https://doc.rust-lang.org/cargo/reference/environment-variables.html
+if [[ -e "/dev/kvm" ]]; then
+  qemu_flags+=(
+    '-enable-kvm'
+    '-cpu' 'Broadwell-IBRS'
+  )
+fi
+
+qemu-system-x86_64 "${qemu_flags[@]}" -kernel "${TARGET}"
+

experimental/uefi/app/src/main.rs

@@ -109,3 +109,6 @@ fn test_simple() {
     let x = 1;
     assert_eq!(x, 1);
 }
+
+#[cfg(test)]
+mod tests;

experimental/uefi/app/src/tests/mod.rs

@@ -0,0 +1,20 @@
+//
+// Copyright 2022 The Project Oak Authors
+//
+// 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.
+//
+
+// Uses advanced CPU features not available when using running tests in qemu
+// with CPU emulation.
+#[cfg(not(feature = "support_emulated_runner"))]
+mod remote_attestation;

experimental/uefi/app/src/tests/remote_attestation.rs

@@ -0,0 +1,110 @@
+//
+// Copyright 2022 The Project Oak Authors
+//
+// 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.
+//
+
+//! Integration Test of Remote Attestation in UEFI.
+//!
+//! This tests that remote attestion works inside the UEFI app. While the test
+//! code is identical to (a subset of) the tests in the remote attestation crate
+//! they here utilize the qemu runner configured in the UEFI app. This means
+//! that test code actually compiled to a UEFI target, which changes the
+//! underlying implementation of the remote attestation crate.
+//! TODO(#2654): It would be preferable to remove the test here, and instead
+//! run the tests in the oak_remote_attestation crate itself for both standard
+//! and UEFI targets. Due to concerns related to the workspace this is presently
+//! not possible. Ref: https://github.com/project-oak/oak/issues/2654
+
+extern crate alloc;
+
+use alloc::{boxed::Box, sync::Arc};
+use oak_remote_attestation::handshaker::{AttestationBehavior, ClientHandshaker, ServerHandshaker};
+
+const TEE_MEASUREMENT: &str = "Test TEE measurement";
+const DATA: [u8; 10] = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
+
+fn create_handshakers() -> (ClientHandshaker, ServerHandshaker) {
+    let bidirectional_attestation =
+        AttestationBehavior::create_bidirectional_attestation(&[], TEE_MEASUREMENT.as_bytes())
+            .unwrap();
+    let client_handshaker = ClientHandshaker::new(
+        bidirectional_attestation,
+        Box::new(|server_identity| {
+            if !server_identity.additional_info.is_empty() {
+                Ok(())
+            } else {
+                anyhow::bail!("No additional info provided.")
+            }
+        }),
+    );
+
+    let bidirectional_attestation =
+        AttestationBehavior::create_bidirectional_attestation(&[], TEE_MEASUREMENT.as_bytes())
+            .unwrap();
+
+    let additional_info = br"Additional Info".to_vec();
+    let server_handshaker =
+        ServerHandshaker::new(bidirectional_attestation, Arc::new(additional_info));
+
+    (client_handshaker, server_handshaker)
+}
+
+#[test_case]
+fn test_handshake() {
+    let (mut client_handshaker, mut server_handshaker) = create_handshakers();
+
+    let client_hello = client_handshaker
+        .create_client_hello()
+        .expect("Couldn't create client hello message");
+
+    let server_identity = server_handshaker
+        .next_step(&client_hello)
+        .expect("Couldn't process client hello message")
+        .expect("Empty server identity message");
+
+    let client_identity = client_handshaker
+        .next_step(&server_identity)
+        .expect("Couldn't process server identity message")
+        .expect("Empty client identity message");
+    assert!(client_handshaker.is_completed());
+
+    let result = server_handshaker
+        .next_step(&client_identity)
+        .expect("Couldn't process client identity message");
+    assert_eq!(result, None);
+    assert!(server_handshaker.is_completed());
+
+    let mut client_encryptor = client_handshaker
+        .get_encryptor()
+        .expect("Couldn't get client encryptor");
+    let mut server_encryptor = server_handshaker
+        .get_encryptor()
+        .expect("Couldn't get server encryptor");
+
+    let encrypted_client_data = client_encryptor
+        .encrypt(&DATA)
+        .expect("Couldn't encrypt client data");
+    let decrypted_client_data = server_encryptor
+        .decrypt(&encrypted_client_data)
+        .expect("Couldn't decrypt client data");
+    assert_eq!(decrypted_client_data, DATA);
+
+    let encrypted_server_data = server_encryptor
+        .encrypt(&DATA)
+        .expect("Couldn't encrypt server data");
+    let decrypted_server_data = client_encryptor
+        .decrypt(&encrypted_server_data)
+        .expect("Couldn't decrypt server data");
+    assert_eq!(decrypted_server_data, DATA);
+}

remote_attestation/rust/Cargo.toml

@@ -14,7 +14,7 @@ anyhow = { version = "*", default-features = false }
 bytes = { version = "*", default-features = false }
 log = "*"
 prost = { version = "*", default-features = false, features = ["prost-derive"] }
-ring = { path = "../../third_party/ring" }
+ring = { path = "../../third_party/ring", default-features = false }
 
 [build-dependencies]
 prost-build = "*"

third_party/ring/Cargo.toml

@@ -33,6 +33,8 @@ include = [
     "benches/*.rs",
     "build.rs",
 
+    "stubs.c",
+
     "crypto/chacha/asm/chacha-armv4.pl",
     "crypto/chacha/asm/chacha-armv8.pl",
     "crypto/chacha/asm/chacha-x86.pl",

third_party/ring/build.rs

@@ -55,6 +55,7 @@ const RING_SRCS: &[(&[&str], &str)] = &[
     (&[X86], "crypto/chacha/asm/chacha-x86.pl"),
     (&[X86], "crypto/fipsmodule/modes/asm/ghash-x86.pl"),
 
+    (&[X86_64], "stubs.c"),
     (&[X86_64], "crypto/chacha/asm/chacha-x86_64.pl"),
     (&[X86_64], "crypto/fipsmodule/aes/asm/aesni-x86_64.pl"),
     (&[X86_64], "crypto/fipsmodule/aes/asm/vpaes-x86_64.pl"),

third_party/ring/stubs.c

@@ -0,0 +1,30 @@
+#include <stddef.h>
+
+/**
+ *
+  Stub function for win64 error handler API call inserted by nasm.
+  Stubbed as it is unavailable in UEFI. It appears unlikely this call will 
+  ever be invoked in deployment.
+  Ref: https://github.com/openssl/openssl/issues/12712.
+  Inspired by: https://github.com/tianocore/edk2/blob/7c0ad2c33810ead45b7919f8f8d0e282dae52e71/CryptoPkg/Library/OpensslLib/X64/ApiHooks.c
+**/
+void *
+__imp_RtlVirtualUnwind (
+  void  *Args
+  )
+{
+  return NULL;
+}
+
+/**
+  Stub function for win64 routine used for exceedingly large variables.
+  Inserted nasm, stubbed as it is unavailable in UEFI. Given that this 
+  routine is used for very large variable it appears unlikely to ever be
+  invoked in deployment.
+  Ref: https://github.com/golang/go/issues/6305
+  Inspired by: https://android.googlesource.com/platform/external/compiler-rt/+/ccaafe6%5E%21/#F1
+**/
+void ___chkstk_ms(void)
+{
+}
+

xtask/src/main.rs

@@ -585,6 +585,9 @@ fn run_clang_format(mode: FormatMode) -> Step {
                     "--recursive",
                     "--exclude",
                     "*/node_modules",
+                    // TODO(#2654): Remove once all crates are part of the same workspace again
+                    "--exclude",
+                    "*/target",
                     "--exclude",
                     "third_party",
                     "oak_functions",