diff --git a/ondevice-signing/Android.bp b/ondevice-signing/Android.bp
index efa0389..42d3074 100644
--- a/ondevice-signing/Android.bp
+++ b/ondevice-signing/Android.bp
@@ -74,6 +74,34 @@
   ],
 }
 
+cc_library {
+  name: "libsigningutils",
+  defaults: [
+    "odsign_flags_defaults",
+  ],
+  cpp_std: "experimental",
+  srcs: [
+    "CertUtils.cpp",
+    "VerityUtils.cpp",
+  ],
+
+  static_libs: [
+    "libc++fs",
+    "lib_compos_proto",
+  ],
+
+  shared_libs: [
+    "libbase",
+    "libcrypto",
+    "libcrypto_utils",
+    "libfsverity",
+    "libprotobuf-cpp-lite",
+    "libutils",
+  ],
+  export_include_dirs: ["include"],
+  recovery_available: true,
+}
+
 cc_binary {
   name: "odsign",
   defaults: [
@@ -82,21 +110,19 @@
   cpp_std: "experimental",
   init_rc: ["odsign.rc"],
   srcs: [
-    "odsign_main.cpp",
-    "CertUtils.cpp",
     "KeystoreKey.cpp",
     "KeystoreHmacKey.cpp",
-    "VerityUtils.cpp",
+    "odsign_main.cpp",
   ],
 
   header_libs: ["odrefresh_headers"],
 
   static_libs: [
     "libc++fs",
+    "libsigningutils",
     "lib_odsign_proto",
     "lib_compos_proto",
   ],
-
   shared_libs: [
     "android.system.keystore2-V1-cpp",
     "android.hardware.security.keymint-V1-cpp",
diff --git a/ondevice-signing/TEST_MAPPING b/ondevice-signing/TEST_MAPPING
new file mode 100644
index 0000000..4b2c8c6
--- /dev/null
+++ b/ondevice-signing/TEST_MAPPING
@@ -0,0 +1,7 @@
+{
+  "presubmit": [
+    {
+      "name": "libsigningutils_test"
+    }
+  ]
+}
diff --git a/ondevice-signing/CertUtils.h b/ondevice-signing/include/CertUtils.h
similarity index 100%
rename from ondevice-signing/CertUtils.h
rename to ondevice-signing/include/CertUtils.h
diff --git a/ondevice-signing/SigningKey.h b/ondevice-signing/include/SigningKey.h
similarity index 100%
rename from ondevice-signing/SigningKey.h
rename to ondevice-signing/include/SigningKey.h
diff --git a/ondevice-signing/VerityUtils.h b/ondevice-signing/include/VerityUtils.h
similarity index 100%
rename from ondevice-signing/VerityUtils.h
rename to ondevice-signing/include/VerityUtils.h
diff --git a/ondevice-signing/proto/Android.bp b/ondevice-signing/proto/Android.bp
index c042b8e..4b8921e 100644
--- a/ondevice-signing/proto/Android.bp
+++ b/ondevice-signing/proto/Android.bp
@@ -40,4 +40,5 @@
         "//apex_available:platform",
         "com.android.compos",
     ],
+    recovery_available: true,
 }
diff --git a/ondevice-signing/tests/Android.bp b/ondevice-signing/tests/Android.bp
new file mode 100644
index 0000000..9769ca8
--- /dev/null
+++ b/ondevice-signing/tests/Android.bp
@@ -0,0 +1,35 @@
+// 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.
+
+cc_test {
+  name: "libsigningutils_test",
+  srcs: ["SigningUtilsTest.cpp"],
+  test_suites: ["device-tests"],
+  compile_multilib: "both",
+  defaults: [
+    "odsign_flags_defaults",
+  ],
+  static_libs: [
+    "libsigningutils",
+  ],
+  shared_libs: [
+    "libbase",
+    "libcrypto",
+  ],
+  data: [
+    "test_file",
+    "test_file.sig",
+    "SigningUtils.cert.der",
+  ],
+}
diff --git a/ondevice-signing/tests/SigningUtils.cert.der b/ondevice-signing/tests/SigningUtils.cert.der
new file mode 100644
index 0000000..0703d59
--- /dev/null
+++ b/ondevice-signing/tests/SigningUtils.cert.der
Binary files differ
diff --git a/ondevice-signing/tests/SigningUtils.pem b/ondevice-signing/tests/SigningUtils.pem
new file mode 100644
index 0000000..01dfa5e
--- /dev/null
+++ b/ondevice-signing/tests/SigningUtils.pem
@@ -0,0 +1,51 @@
+-----BEGIN RSA PRIVATE KEY-----
+MIIJKAIBAAKCAgEAwyOUvcTpPuPxw2I9E28uhXT9pbJAgNE0dc1emOWRfapZ5iow
+6PC7am47DfHyyZ/dwtw0vvi3QWCLIpsyFQbspO5XfmJH7mHBTvG8SkV40rFjptf8
+iwMl5i1ZUc5LChxuRh6DIS1fT2tFiXQ8iX3FUNNqjj/tOOtp45JEsgFK7WDW8YU3
+UseUn2BpkccUHMbe78EkEb4F6/AJWISk2INMOMPzRPUwdE3eUPVrufkp6jVJs69I
+c6skRvAAqpiOx4rYpVzs3V5PuzhmCr7jt8hTQ0DA6q501UT06og6gIKPdqLjugKK
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+l13MOMbVeT3ipaRGMwD1bp7kBW3cEZ2zrQ4WSwwtADeWI6Z0k5SpcHfLxp+6dhPN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+gOk+9W6cM84p+2+DIGI8fydnuIv8q6TFiouDCY+T3FVdj4MasNZuAeHR7c6Coc5N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+Mg590sr7jby8J9h2MsHVzUb4fPJfFh0CggEBANS+aqEzWflHMOR4knhM7QHHaTfS
+4wwR3zL3/tSaV/cxNGehtjyEg85/aKklt/ude3/sm/Z0m6jQEMWgAt5iwuBovPA+
+1/rGkWTHL+dQr0i81C3b/Ymx7izL7BobaYV0o00EoKotC0NP5qR0fBKSkTfFqAYG
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+Iz3zcytrZZbAuOjCnhxNL/6XgcttqWSVFB4Ul1xiXrXDx2Xq+FfM40UF7oKGd+Kt
+B0wMqoZJj+0CdFfRZxHA6/n8v1Al+8lYo8smp+R9fR6qZKcugEFgdVkIl7E=
+-----END RSA PRIVATE KEY-----
diff --git a/ondevice-signing/tests/SigningUtilsTest.cpp b/ondevice-signing/tests/SigningUtilsTest.cpp
new file mode 100644
index 0000000..10f7629
--- /dev/null
+++ b/ondevice-signing/tests/SigningUtilsTest.cpp
@@ -0,0 +1,48 @@
+/*
+ * 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.
+ */
+
+#include <android-base/file.h>
+#include <gtest/gtest.h>
+
+#include "CertUtils.h"
+#include "VerityUtils.h"
+
+// These files were created using the following commands:
+// openssl genrsa -out SigningUtils.pem 4096
+// openssl req -new -x509 -key SigningUtils.pem -out SigningUtils.cert.pem
+// openssl x509 -in SigningUtils.cert.pem -out SigningUtils.cert.der -outform DER
+// head -c 4096 </dev/urandom >test_file
+// openssl dgst -sign SigningUtils.pem -keyform PEM -sha256 -out test_file.sig -binary test_file
+const std::string kTestCert = "SigningUtils.cert.der";
+const std::string kTestFile = "test_file";
+const std::string kTestFileSignature = "test_file.sig";
+
+TEST(SigningUtilsTest, CheckVerifySignature) {
+    std::string signature;
+    std::string sigFile = android::base::GetExecutableDirectory() + "/" + kTestFileSignature;
+    ASSERT_TRUE(android::base::ReadFileToString(sigFile, &signature));
+
+    std::string data;
+    std::string testFile = android::base::GetExecutableDirectory() + "/" + kTestFile;
+    ASSERT_TRUE(android::base::ReadFileToString(testFile, &data));
+
+    std::string testCert = android::base::GetExecutableDirectory() + "/" + kTestCert;
+    auto trustedKey = extractPublicKeyFromX509(testCert.c_str());
+    ASSERT_TRUE(trustedKey.ok());
+
+    auto result = verifySignature(data, signature, *trustedKey);
+    ASSERT_TRUE(result.ok());
+}
diff --git a/ondevice-signing/tests/test_file b/ondevice-signing/tests/test_file
new file mode 100644
index 0000000..8a121be
--- /dev/null
+++ b/ondevice-signing/tests/test_file
Binary files differ
diff --git a/ondevice-signing/tests/test_file.sig b/ondevice-signing/tests/test_file.sig
new file mode 100644
index 0000000..ffd95dc
--- /dev/null
+++ b/ondevice-signing/tests/test_file.sig
Binary files differ