binder: make libbinder_tls_test_utils
... by combining various RpcAuth / RpcCertificateVerifier
implementations for tests.
This allows us to move more TLS test utils to this library.
Test: pass
Bug: 195598155
Change-Id: Ic7861ac9585c6fc2bbceef7322fb18db4d2e2d11
diff --git a/libs/binder/tests/RpcTlsTestUtils.cpp b/libs/binder/tests/RpcTlsTestUtils.cpp
new file mode 100644
index 0000000..6119313
--- /dev/null
+++ b/libs/binder/tests/RpcTlsTestUtils.cpp
@@ -0,0 +1,118 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#define LOG_TAG "RpcTlsTestUtils"
+#include <log/log.h>
+
+#include <binder/RpcTlsTestUtils.h>
+
+#include <binder/RpcTlsUtils.h>
+
+#include "../Utils.h" // for TEST_AND_RETURN
+
+namespace android {
+
+bssl::UniquePtr<EVP_PKEY> makeKeyPairForSelfSignedCert() {
+ bssl::UniquePtr<EC_KEY> ec_key(EC_KEY_new_by_curve_name(NID_X9_62_prime256v1));
+ if (ec_key == nullptr || !EC_KEY_generate_key(ec_key.get())) {
+ ALOGE("Failed to generate key pair.");
+ return nullptr;
+ }
+ bssl::UniquePtr<EVP_PKEY> pkey(EVP_PKEY_new());
+ // Use set1 instead of assign to avoid leaking ec_key when assign fails. set1 increments
+ // the refcount of the ec_key, so it is okay to release it at the end of this function.
+ if (pkey == nullptr || !EVP_PKEY_set1_EC_KEY(pkey.get(), ec_key.get())) {
+ ALOGE("Failed to assign key pair.");
+ return nullptr;
+ }
+ return pkey;
+}
+
+bssl::UniquePtr<X509> makeSelfSignedCert(EVP_PKEY* pkey, const uint32_t validSeconds) {
+ bssl::UniquePtr<X509> x509(X509_new());
+ bssl::UniquePtr<BIGNUM> serial(BN_new());
+ bssl::UniquePtr<BIGNUM> serialLimit(BN_new());
+ TEST_AND_RETURN(nullptr, BN_lshift(serialLimit.get(), BN_value_one(), 128));
+ TEST_AND_RETURN(nullptr, BN_rand_range(serial.get(), serialLimit.get()));
+ TEST_AND_RETURN(nullptr, BN_to_ASN1_INTEGER(serial.get(), X509_get_serialNumber(x509.get())));
+ TEST_AND_RETURN(nullptr, X509_gmtime_adj(X509_getm_notBefore(x509.get()), 0));
+ TEST_AND_RETURN(nullptr, X509_gmtime_adj(X509_getm_notAfter(x509.get()), validSeconds));
+
+ X509_NAME* subject = X509_get_subject_name(x509.get());
+ TEST_AND_RETURN(nullptr,
+ X509_NAME_add_entry_by_txt(subject, "O", MBSTRING_ASC,
+ reinterpret_cast<const uint8_t*>("Android"), -1, -1,
+ 0));
+ TEST_AND_RETURN(nullptr,
+ X509_NAME_add_entry_by_txt(subject, "CN", MBSTRING_ASC,
+ reinterpret_cast<const uint8_t*>("BinderRPC"), -1,
+ -1, 0));
+ TEST_AND_RETURN(nullptr, X509_set_issuer_name(x509.get(), subject));
+
+ TEST_AND_RETURN(nullptr, X509_set_pubkey(x509.get(), pkey));
+ TEST_AND_RETURN(nullptr, X509_sign(x509.get(), pkey, EVP_sha256()));
+ return x509;
+}
+
+status_t RpcAuthSelfSigned::configure(SSL_CTX* ctx) {
+ auto pkey = makeKeyPairForSelfSignedCert();
+ TEST_AND_RETURN(UNKNOWN_ERROR, pkey != nullptr);
+ auto cert = makeSelfSignedCert(pkey.get(), mValidSeconds);
+ TEST_AND_RETURN(UNKNOWN_ERROR, cert != nullptr);
+ TEST_AND_RETURN(INVALID_OPERATION, SSL_CTX_use_PrivateKey(ctx, pkey.get()));
+ TEST_AND_RETURN(INVALID_OPERATION, SSL_CTX_use_certificate(ctx, cert.get()));
+ return OK;
+}
+
+status_t RpcAuthPreSigned::configure(SSL_CTX* ctx) {
+ if (!SSL_CTX_use_PrivateKey(ctx, mPkey.get())) {
+ return INVALID_OPERATION;
+ }
+ if (!SSL_CTX_use_certificate(ctx, mCert.get())) {
+ return INVALID_OPERATION;
+ }
+ return OK;
+}
+
+status_t RpcCertificateVerifierSimple::verify(const SSL* ssl, uint8_t* outAlert) {
+ const char* logPrefix = SSL_is_server(ssl) ? "Server" : "Client";
+ bssl::UniquePtr<X509> peerCert(SSL_get_peer_certificate(ssl)); // Does not set error queue
+ LOG_ALWAYS_FATAL_IF(peerCert == nullptr,
+ "%s: libssl should not ask to verify non-existing cert", logPrefix);
+
+ std::lock_guard<std::mutex> lock(mMutex);
+ for (const auto& trustedCert : mTrustedPeerCertificates) {
+ if (0 == X509_cmp(trustedCert.get(), peerCert.get())) {
+ return OK;
+ }
+ }
+ *outAlert = SSL_AD_CERTIFICATE_UNKNOWN;
+ return PERMISSION_DENIED;
+}
+
+status_t RpcCertificateVerifierSimple::addTrustedPeerCertificate(RpcCertificateFormat format,
+ const std::vector<uint8_t>& cert) {
+ bssl::UniquePtr<X509> x509 = deserializeCertificate(cert, format);
+ if (x509 == nullptr) {
+ ALOGE("Certificate is not in the proper format %s", PrintToString(format).c_str());
+ return BAD_VALUE;
+ }
+ std::lock_guard<std::mutex> lock(mMutex);
+ mTrustedPeerCertificates.push_back(std::move(x509));
+ return OK;
+}
+
+} // namespace android