diff --git a/tests/Android.bp b/tests/Android.bp
index 898ed7d..ef5919e 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -77,6 +77,7 @@
     "librecovery",
     "librecovery_fastboot",
     "libminui",
+    "libpackage",
     "libverifier",
     "libotautil",
 
@@ -117,6 +118,7 @@
     static_libs: libapplypatch_static_libs + [
         "librecovery_ui",
         "libminui",
+        "libpackage",
         "libverifier",
         "libotautil",
         "libupdater",
diff --git a/tests/component/verifier_test.cpp b/tests/component/verifier_test.cpp
index c26d76d..c904cd0 100644
--- a/tests/component/verifier_test.cpp
+++ b/tests/component/verifier_test.cpp
@@ -240,8 +240,10 @@
   void SetUp() override {
     std::vector<std::string> args = GetParam();
     std::string path = from_testdata_base(args[0]);
-    package_ = Package::CreateMemoryPackage(path, nullptr);
-    ASSERT_NE(nullptr, package_);
+    memory_package_ = Package::CreateMemoryPackage(path, nullptr);
+    ASSERT_NE(nullptr, memory_package_);
+    file_package_ = Package::CreateFilePackage(path, nullptr);
+    ASSERT_NE(nullptr, file_package_);
 
     for (auto it = ++args.cbegin(); it != args.cend(); ++it) {
       std::string public_key_file = from_testdata_base("testkey_" + *it + ".x509.pem");
@@ -250,7 +252,8 @@
     }
   }
 
-  std::unique_ptr<Package> package_;
+  std::unique_ptr<Package> memory_package_;
+  std::unique_ptr<Package> file_package_;
   std::vector<Certificate> certs_;
 };
 
@@ -304,11 +307,13 @@
 }
 
 TEST_P(VerifierSuccessTest, VerifySucceed) {
-  ASSERT_EQ(VERIFY_SUCCESS, verify_file(package_.get(), certs_));
+  ASSERT_EQ(VERIFY_SUCCESS, verify_file(memory_package_.get(), certs_));
+  ASSERT_EQ(VERIFY_SUCCESS, verify_file(file_package_.get(), certs_));
 }
 
 TEST_P(VerifierFailureTest, VerifyFailure) {
-  ASSERT_EQ(VERIFY_FAILURE, verify_file(package_.get(), certs_));
+  ASSERT_EQ(VERIFY_FAILURE, verify_file(memory_package_.get(), certs_));
+  ASSERT_EQ(VERIFY_FAILURE, verify_file(file_package_.get(), certs_));
 }
 
 INSTANTIATE_TEST_CASE_P(SingleKeySuccess, VerifierSuccessTest,
diff --git a/tests/unit/package_test.cpp b/tests/unit/package_test.cpp
new file mode 100644
index 0000000..fa492d3
--- /dev/null
+++ b/tests/unit/package_test.cpp
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2019 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 agree 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 <stdio.h>
+
+#include <functional>
+#include <string>
+#include <vector>
+
+#include <android-base/file.h>
+#include <gtest/gtest.h>
+#include <openssl/sha.h>
+#include <ziparchive/zip_writer.h>
+
+#include "common/test_constants.h"
+#include "package.h"
+
+class PackageTest : public ::testing::Test {
+ protected:
+  void SetUp() override;
+
+  // A list of package classes for test, including MemoryPackage and FilePackage.
+  std::vector<std::unique_ptr<Package>> packages_;
+
+  TemporaryFile temp_file_;   // test package file.
+  std::string file_content_;  // actual bytes of the package file.
+};
+
+void PackageTest::SetUp() {
+  std::vector<std::string> entries = { "file1.txt", "file2.txt", "dir1/file3.txt" };
+  FILE* file_ptr = fdopen(temp_file_.release(), "wb");
+  ZipWriter writer(file_ptr);
+  for (const auto& entry : entries) {
+    ASSERT_EQ(0, writer.StartEntry(entry.c_str(), ZipWriter::kCompress));
+    ASSERT_EQ(0, writer.WriteBytes(entry.c_str(), entry.size()));
+    ASSERT_EQ(0, writer.FinishEntry());
+  }
+  writer.Finish();
+  ASSERT_EQ(0, fclose(file_ptr));
+
+  ASSERT_TRUE(android::base::ReadFileToString(temp_file_.path, &file_content_));
+  auto memory_package = Package::CreateMemoryPackage(temp_file_.path, nullptr);
+  ASSERT_TRUE(memory_package);
+  packages_.emplace_back(std::move(memory_package));
+
+  auto file_package = Package::CreateFilePackage(temp_file_.path, nullptr);
+  ASSERT_TRUE(file_package);
+  packages_.emplace_back(std::move(file_package));
+}
+
+TEST_F(PackageTest, ReadFullyAtOffset_success) {
+  for (const auto& package : packages_) {
+    std::vector<uint8_t> buffer(file_content_.size());
+    ASSERT_TRUE(package->ReadFullyAtOffset(buffer.data(), file_content_.size(), 0));
+    ASSERT_EQ(file_content_, std::string(buffer.begin(), buffer.end()));
+
+    ASSERT_TRUE(package->ReadFullyAtOffset(buffer.data(), file_content_.size() - 10, 10));
+    ASSERT_EQ(file_content_.substr(10), std::string(buffer.begin(), buffer.end() - 10));
+  }
+}
+
+TEST_F(PackageTest, ReadFullyAtOffset_failure) {
+  for (const auto& package : packages_) {
+    std::vector<uint8_t> buffer(file_content_.size());
+    // Out of bound read.
+    ASSERT_FALSE(package->ReadFullyAtOffset(buffer.data(), file_content_.size(), 10));
+  }
+}
+
+TEST_F(PackageTest, UpdateHashAtOffset_sha1_hash) {
+  // Check that the hash matches for first half of the file.
+  uint64_t hash_size = file_content_.size() / 2;
+  std::vector<uint8_t> expected_sha(SHA_DIGEST_LENGTH);
+  SHA1(reinterpret_cast<uint8_t*>(file_content_.data()), hash_size, expected_sha.data());
+
+  for (const auto& package : packages_) {
+    SHA_CTX ctx;
+    SHA1_Init(&ctx);
+    std::vector<HasherUpdateCallback> hashers{ std::bind(&SHA1_Update, &ctx, std::placeholders::_1,
+                                                         std::placeholders::_2) };
+    package->UpdateHashAtOffset(hashers, 0, hash_size);
+
+    std::vector<uint8_t> calculated_sha(SHA_DIGEST_LENGTH);
+    SHA1_Final(calculated_sha.data(), &ctx);
+    ASSERT_EQ(expected_sha, calculated_sha);
+  }
+}
+
+TEST_F(PackageTest, GetZipArchiveHandle_extract_entry) {
+  for (const auto& package : packages_) {
+    ZipArchiveHandle zip = package->GetZipArchiveHandle();
+    ASSERT_TRUE(zip);
+
+    // Check that we can extract one zip entry.
+    std::string entry_name = "dir1/file3.txt";
+    ZipString path(entry_name.c_str());
+    ZipEntry entry;
+    ASSERT_EQ(0, FindEntry(zip, path, &entry));
+
+    std::vector<uint8_t> extracted(entry_name.size());
+    ASSERT_EQ(0, ExtractToMemory(zip, &entry, extracted.data(), extracted.size()));
+    ASSERT_EQ(entry_name, std::string(extracted.begin(), extracted.end()));
+  }
+}