recovery: Restore block based OTA functions

We still use these for our signing process. Bring back the
functions and update them to the proper format

This reverts commit 53c38b15381ace565227e49104a6fd64c4c28dcc.
This reverts commit 63d786cf22cb44fe32e8b9c1f18b32da3c9d2e1b.

Change-Id: I73d6f3e228c2b97f953345c13f8f43189a924a5e

8 files changed, 1010 insertions, 0 deletions

diff --git a/otautil/Android.bp b/otautil/Android.bp
index a2eaa040..0b231437 100644
--- a/otautil/Android.bp
+++ b/otautil/Android.bp
@@ -18,6 +18,7 @@ cc_library_static {
     srcs: [
         "SysUtil.cpp",
         "DirUtil.cpp",
+        "ZipUtil.cpp",
         "ThermalUtil.cpp",
     ],
 
diff --git a/otautil/ZipUtil.cpp b/otautil/ZipUtil.cpp
new file mode 100644
index 00000000..9cc97e49
--- /dev/null
+++ b/otautil/ZipUtil.cpp
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2016 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 "ZipUtil.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <utime.h>
+
+#include <string>
+
+#include <android-base/logging.h>
+#include <android-base/unique_fd.h>
+#include <selinux/label.h>
+#include <selinux/selinux.h>
+#include <ziparchive/zip_archive.h>
+
+#include "DirUtil.h"
+
+static constexpr mode_t UNZIP_DIRMODE = 0755;
+static constexpr mode_t UNZIP_FILEMODE = 0644;
+
+bool ExtractPackageRecursive(ZipArchiveHandle zip, const std::string& zip_path,
+                             const std::string& dest_path, const struct utimbuf* timestamp,
+                             struct selabel_handle* sehnd) {
+    if (!zip_path.empty() && zip_path[0] == '/') {
+        LOG(ERROR) << "ExtractPackageRecursive(): zip_path must be a relative path " << zip_path;
+        return false;
+    }
+    if (dest_path.empty() || dest_path[0] != '/') {
+        LOG(ERROR) << "ExtractPackageRecursive(): dest_path must be an absolute path " << dest_path;
+        return false;
+    }
+
+    void* cookie;
+    std::string target_dir(dest_path);
+    if (dest_path.back() != '/') {
+        target_dir += '/';
+    }
+    std::string prefix_path(zip_path);
+    if (!zip_path.empty() && zip_path.back() != '/') {
+        prefix_path += '/';
+    }
+    const ZipString zip_prefix(prefix_path.c_str());
+
+    int ret = StartIteration(zip, &cookie, &zip_prefix, nullptr);
+    if (ret != 0) {
+        LOG(ERROR) << "failed to start iterating zip entries.";
+        return false;
+    }
+
+    std::unique_ptr<void, decltype(&EndIteration)> guard(cookie, EndIteration);
+    ZipEntry entry;
+    ZipString name;
+    int extractCount = 0;
+    while (Next(cookie, &entry, &name) == 0) {
+        std::string entry_name(name.name, name.name + name.name_length);
+        CHECK_LE(prefix_path.size(), entry_name.size());
+        std::string path = target_dir + entry_name.substr(prefix_path.size());
+        // Skip dir.
+        if (path.back() == '/') {
+            continue;
+        }
+
+        if (dirCreateHierarchy(path.c_str(), UNZIP_DIRMODE, timestamp, true, sehnd) != 0) {
+            LOG(ERROR) << "failed to create dir for " << path;
+            return false;
+        }
+
+        char *secontext = NULL;
+        if (sehnd) {
+            selabel_lookup(sehnd, &secontext, path.c_str(), UNZIP_FILEMODE);
+            setfscreatecon(secontext);
+        }
+        android::base::unique_fd fd(open(path.c_str(), O_CREAT|O_WRONLY|O_TRUNC, UNZIP_FILEMODE));
+        if (fd == -1) {
+            PLOG(ERROR) << "Can't create target file \"" << path << "\"";
+            return false;
+        }
+        if (secontext) {
+            freecon(secontext);
+            setfscreatecon(NULL);
+        }
+
+        int err = ExtractEntryToFile(zip, &entry, fd);
+        if (err != 0) {
+            LOG(ERROR) << "Error extracting \"" << path << "\" : " << ErrorCodeString(err);
+            return false;
+        }
+
+        if (fsync(fd) != 0) {
+            PLOG(ERROR) << "Error syncing file descriptor when extracting \"" << path << "\"";
+            return false;
+        }
+
+        if (timestamp != nullptr && utime(path.c_str(), timestamp)) {
+            PLOG(ERROR) << "Error touching \"" << path << "\"";
+            return false;
+        }
+
+        LOG(INFO) << "Extracted file \"" << path << "\"";
+        ++extractCount;
+    }
+
+    LOG(INFO) << "Extracted " << extractCount << " file(s)";
+    return true;
+}
diff --git a/otautil/ZipUtil.h b/otautil/ZipUtil.h
new file mode 100644
index 00000000..cda405c2
--- /dev/null
+++ b/otautil/ZipUtil.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef _OTAUTIL_ZIPUTIL_H
+#define _OTAUTIL_ZIPUTIL_H
+
+#include <utime.h>
+
+#include <string>
+
+#include <selinux/label.h>
+#include <ziparchive/zip_archive.h>
+
+/*
+ * Inflate all files under zip_path to the directory specified by
+ * dest_path, which must exist and be a writable directory. The zip_path
+ * is allowed to be an empty string, in which case the whole package
+ * will be extracted.
+ *
+ * Directory entries are not extracted.
+ *
+ * The immediate children of zip_path will become the immediate
+ * children of dest_path; e.g., if the archive contains the entries
+ *
+ *     a/b/c/one
+ *     a/b/c/two
+ *     a/b/c/d/three
+ *
+ * and ExtractPackageRecursive(a, "a/b/c", "/tmp", ...) is called, the resulting
+ * files will be
+ *
+ *     /tmp/one
+ *     /tmp/two
+ *     /tmp/d/three
+ *
+ * If timestamp is non-NULL, file timestamps will be set accordingly.
+ *
+ * Returns true on success, false on failure.
+ */
+bool ExtractPackageRecursive(ZipArchiveHandle zip, const std::string& zip_path,
+                             const std::string& dest_path, const struct utimbuf* timestamp,
+                             struct selabel_handle* sehnd);
+
+#endif // _OTAUTIL_ZIPUTIL_H
diff --git a/tests/Android.mk b/tests/Android.mk
index f2497b8b..12bd7475 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -39,6 +39,7 @@ LOCAL_SRC_FILES := \
     unit/rangeset_test.cpp \
     unit/sysutil_test.cpp \
     unit/zip_test.cpp \
+    unit/ziputil_test.cpp
 
 LOCAL_C_INCLUDES := bootable/recovery
 LOCAL_SHARED_LIBRARIES := liblog
diff --git a/tests/component/updater_test.cpp b/tests/component/updater_test.cpp
index 6c341c11..374a99c8 100644
--- a/tests/component/updater_test.cpp
+++ b/tests/component/updater_test.cpp
@@ -227,6 +227,215 @@ TEST_F(UpdaterTest, file_getprop) {
     expect("", script6.c_str(), kNoCause);
 }
 
+TEST_F(UpdaterTest, delete) {
+    // Delete none.
+    expect("0", "delete()", kNoCause);
+    expect("0", "delete(\"/doesntexist\")", kNoCause);
+    expect("0", "delete(\"/doesntexist1\", \"/doesntexist2\")", kNoCause);
+    expect("0", "delete(\"/doesntexist1\", \"/doesntexist2\", \"/doesntexist3\")", kNoCause);
+
+    // Delete one file.
+    TemporaryFile temp_file1;
+    ASSERT_TRUE(android::base::WriteStringToFile("abc", temp_file1.path));
+    std::string script1("delete(\"" + std::string(temp_file1.path) + "\")");
+    expect("1", script1.c_str(), kNoCause);
+
+    // Delete two files.
+    TemporaryFile temp_file2;
+    ASSERT_TRUE(android::base::WriteStringToFile("abc", temp_file2.path));
+    TemporaryFile temp_file3;
+    ASSERT_TRUE(android::base::WriteStringToFile("abc", temp_file3.path));
+    std::string script2("delete(\"" + std::string(temp_file2.path) + "\", \"" +
+                        std::string(temp_file3.path) + "\")");
+    expect("2", script2.c_str(), kNoCause);
+
+    // Delete already deleted files.
+    expect("0", script2.c_str(), kNoCause);
+
+    // Delete one out of three.
+    TemporaryFile temp_file4;
+    ASSERT_TRUE(android::base::WriteStringToFile("abc", temp_file4.path));
+    std::string script3("delete(\"/doesntexist1\", \"" + std::string(temp_file4.path) +
+                        "\", \"/doesntexist2\")");
+    expect("1", script3.c_str(), kNoCause);
+}
+
+TEST_F(UpdaterTest, rename) {
+    // rename() expects two arguments.
+    expect(nullptr, "rename()", kArgsParsingFailure);
+    expect(nullptr, "rename(\"arg1\")", kArgsParsingFailure);
+    expect(nullptr, "rename(\"arg1\", \"arg2\", \"arg3\")", kArgsParsingFailure);
+
+    // src_name or dst_name cannot be empty.
+    expect(nullptr, "rename(\"\", \"arg2\")", kArgsParsingFailure);
+    expect(nullptr, "rename(\"arg1\", \"\")", kArgsParsingFailure);
+
+    // File doesn't exist (both of src and dst).
+    expect(nullptr, "rename(\"/doesntexist\", \"/doesntexisteither\")" , kFileRenameFailure);
+
+    // Can't create parent directory.
+    TemporaryFile temp_file1;
+    ASSERT_TRUE(android::base::WriteStringToFile("abc", temp_file1.path));
+    std::string script1("rename(\"" + std::string(temp_file1.path) + "\", \"/proc/0/file1\")");
+    expect(nullptr, script1.c_str(), kFileRenameFailure);
+
+    // Rename.
+    TemporaryFile temp_file2;
+    std::string script2("rename(\"" + std::string(temp_file1.path) + "\", \"" +
+                        std::string(temp_file2.path) + "\")");
+    expect(temp_file2.path, script2.c_str(), kNoCause);
+
+    // Already renamed.
+    expect(temp_file2.path, script2.c_str(), kNoCause);
+
+    // Parents create successfully.
+    TemporaryFile temp_file3;
+    TemporaryDir td;
+    std::string temp_dir(td.path);
+    std::string dst_file = temp_dir + "/aaa/bbb/a.txt";
+    std::string script3("rename(\"" + std::string(temp_file3.path) + "\", \"" + dst_file + "\")");
+    expect(dst_file.c_str(), script3.c_str(), kNoCause);
+
+    // Clean up the temp files under td.
+    ASSERT_EQ(0, unlink(dst_file.c_str()));
+    ASSERT_EQ(0, rmdir((temp_dir + "/aaa/bbb").c_str()));
+    ASSERT_EQ(0, rmdir((temp_dir + "/aaa").c_str()));
+}
+
+TEST_F(UpdaterTest, symlink) {
+    // symlink expects 1+ argument.
+    expect(nullptr, "symlink()", kArgsParsingFailure);
+
+    // symlink should fail if src is an empty string.
+    TemporaryFile temp_file1;
+    std::string script1("symlink(\"" + std::string(temp_file1.path) + "\", \"\")");
+    expect(nullptr, script1.c_str(), kSymlinkFailure);
+
+    std::string script2("symlink(\"" + std::string(temp_file1.path) + "\", \"src1\", \"\")");
+    expect(nullptr, script2.c_str(), kSymlinkFailure);
+
+    // symlink failed to remove old src.
+    std::string script3("symlink(\"" + std::string(temp_file1.path) + "\", \"/proc\")");
+    expect(nullptr, script3.c_str(), kSymlinkFailure);
+
+    // symlink can create symlinks.
+    TemporaryFile temp_file;
+    std::string content = "magicvalue";
+    ASSERT_TRUE(android::base::WriteStringToFile(content, temp_file.path));
+
+    TemporaryDir td;
+    std::string src1 = std::string(td.path) + "/symlink1";
+    std::string src2 = std::string(td.path) + "/symlink2";
+    std::string script4("symlink(\"" + std::string(temp_file.path) + "\", \"" +
+                        src1 + "\", \"" + src2 + "\")");
+    expect("t", script4.c_str(), kNoCause);
+
+    // Verify the created symlinks.
+    struct stat sb;
+    ASSERT_TRUE(lstat(src1.c_str(), &sb) == 0 && S_ISLNK(sb.st_mode));
+    ASSERT_TRUE(lstat(src2.c_str(), &sb) == 0 && S_ISLNK(sb.st_mode));
+
+    // Clean up the leftovers.
+    ASSERT_EQ(0, unlink(src1.c_str()));
+    ASSERT_EQ(0, unlink(src2.c_str()));
+}
+
+TEST_F(UpdaterTest, package_extract_dir) {
+  // package_extract_dir expects 2 arguments.
+  expect(nullptr, "package_extract_dir()", kArgsParsingFailure);
+  expect(nullptr, "package_extract_dir(\"arg1\")", kArgsParsingFailure);
+  expect(nullptr, "package_extract_dir(\"arg1\", \"arg2\", \"arg3\")", kArgsParsingFailure);
+
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Need to set up the ziphandle.
+  UpdaterInfo updater_info;
+  updater_info.package_zip = handle;
+
+  // Extract "b/c.txt" and "b/d.txt" with package_extract_dir("b", "<dir>").
+  TemporaryDir td;
+  std::string temp_dir(td.path);
+  std::string script("package_extract_dir(\"b\", \"" + temp_dir + "\")");
+  expect("t", script.c_str(), kNoCause, &updater_info);
+
+  // Verify.
+  std::string data;
+  std::string file_c = temp_dir + "/c.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_c, &data));
+  ASSERT_EQ(kCTxtContents, data);
+
+  std::string file_d = temp_dir + "/d.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_d, &data));
+  ASSERT_EQ(kDTxtContents, data);
+
+  // Modify the contents in order to retry. It's expected to be overwritten.
+  ASSERT_TRUE(android::base::WriteStringToFile("random", file_c));
+  ASSERT_TRUE(android::base::WriteStringToFile("random", file_d));
+
+  // Extract again and verify.
+  expect("t", script.c_str(), kNoCause, &updater_info);
+
+  ASSERT_TRUE(android::base::ReadFileToString(file_c, &data));
+  ASSERT_EQ(kCTxtContents, data);
+  ASSERT_TRUE(android::base::ReadFileToString(file_d, &data));
+  ASSERT_EQ(kDTxtContents, data);
+
+  // Clean up the temp files under td.
+  ASSERT_EQ(0, unlink(file_c.c_str()));
+  ASSERT_EQ(0, unlink(file_d.c_str()));
+
+  // Extracting "b/" (with slash) should give the same result.
+  script = "package_extract_dir(\"b/\", \"" + temp_dir + "\")";
+  expect("t", script.c_str(), kNoCause, &updater_info);
+
+  ASSERT_TRUE(android::base::ReadFileToString(file_c, &data));
+  ASSERT_EQ(kCTxtContents, data);
+  ASSERT_TRUE(android::base::ReadFileToString(file_d, &data));
+  ASSERT_EQ(kDTxtContents, data);
+
+  ASSERT_EQ(0, unlink(file_c.c_str()));
+  ASSERT_EQ(0, unlink(file_d.c_str()));
+
+  // Extracting "" is allowed. The entries will carry the path name.
+  script = "package_extract_dir(\"\", \"" + temp_dir + "\")";
+  expect("t", script.c_str(), kNoCause, &updater_info);
+
+  std::string file_a = temp_dir + "/a.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_a, &data));
+  ASSERT_EQ(kATxtContents, data);
+  std::string file_b = temp_dir + "/b.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_b, &data));
+  ASSERT_EQ(kBTxtContents, data);
+  std::string file_b_c = temp_dir + "/b/c.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_b_c, &data));
+  ASSERT_EQ(kCTxtContents, data);
+  std::string file_b_d = temp_dir + "/b/d.txt";
+  ASSERT_TRUE(android::base::ReadFileToString(file_b_d, &data));
+  ASSERT_EQ(kDTxtContents, data);
+
+  ASSERT_EQ(0, unlink(file_a.c_str()));
+  ASSERT_EQ(0, unlink(file_b.c_str()));
+  ASSERT_EQ(0, unlink(file_b_c.c_str()));
+  ASSERT_EQ(0, unlink(file_b_d.c_str()));
+  ASSERT_EQ(0, rmdir((temp_dir + "/b").c_str()));
+
+  // Extracting non-existent entry should still give "t".
+  script = "package_extract_dir(\"doesntexist\", \"" + temp_dir + "\")";
+  expect("t", script.c_str(), kNoCause, &updater_info);
+
+  // Only relative zip_path is allowed.
+  script = "package_extract_dir(\"/b\", \"" + temp_dir + "\")";
+  expect("", script.c_str(), kNoCause, &updater_info);
+
+  // Only absolute dest_path is allowed.
+  script = "package_extract_dir(\"b\", \"path\")";
+  expect("", script.c_str(), kNoCause, &updater_info);
+
+  CloseArchive(handle);
+}
+
 // TODO: Test extracting to block device.
 TEST_F(UpdaterTest, package_extract_file) {
   // package_extract_file expects 1 or 2 arguments.
diff --git a/tests/unit/zip_test.cpp b/tests/unit/zip_test.cpp
index 82766852..df4e38ca 100644
--- a/tests/unit/zip_test.cpp
+++ b/tests/unit/zip_test.cpp
@@ -24,10 +24,47 @@
 #include <android-base/test_utils.h>
 #include <gtest/gtest.h>
 #include <otautil/SysUtil.h>
+#include <otautil/ZipUtil.h>
 #include <ziparchive/zip_archive.h>
 
 #include "common/test_constants.h"
 
+TEST(ZipTest, ExtractPackageRecursive) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Extract the whole package into a temp directory.
+  TemporaryDir td;
+  ASSERT_NE(nullptr, td.path);
+  ExtractPackageRecursive(handle, "", td.path, nullptr, nullptr);
+
+  // Make sure all the files are extracted correctly.
+  std::string path(td.path);
+  ASSERT_EQ(0, access((path + "/a.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b/c.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b/d.txt").c_str(), F_OK));
+
+  // The content of the file is the same as expected.
+  std::string content1;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/a.txt", &content1));
+  ASSERT_EQ(kATxtContents, content1);
+
+  std::string content2;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/b/d.txt", &content2));
+  ASSERT_EQ(kDTxtContents, content2);
+
+  CloseArchive(handle);
+
+  // Clean up.
+  ASSERT_EQ(0, unlink((path + "/a.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b/c.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b/d.txt").c_str()));
+  ASSERT_EQ(0, rmdir((path + "/b").c_str()));
+}
+
 TEST(ZipTest, OpenFromMemory) {
   std::string zip_path = from_testdata_base("ziptest_dummy-update.zip");
   MemMapping map;
diff --git a/tests/unit/ziputil_test.cpp b/tests/unit/ziputil_test.cpp
new file mode 100644
index 00000000..14e54169
--- /dev/null
+++ b/tests/unit/ziputil_test.cpp
@@ -0,0 +1,191 @@
+/*
+ * Copyright 2016 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 <errno.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <string>
+
+#include <android-base/file.h>
+#include <android-base/test_utils.h>
+#include <gtest/gtest.h>
+#include <otautil/ZipUtil.h>
+#include <ziparchive/zip_archive.h>
+
+#include "common/test_constants.h"
+
+TEST(ZipUtilTest, invalid_args) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // zip_path must be a relative path.
+  ASSERT_FALSE(ExtractPackageRecursive(handle, "/a/b", "/tmp", nullptr, nullptr));
+
+  // dest_path must be an absolute path.
+  ASSERT_FALSE(ExtractPackageRecursive(handle, "a/b", "tmp", nullptr, nullptr));
+  ASSERT_FALSE(ExtractPackageRecursive(handle, "a/b", "", nullptr, nullptr));
+
+  CloseArchive(handle);
+}
+
+TEST(ZipUtilTest, extract_all) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Extract the whole package into a temp directory.
+  TemporaryDir td;
+  ExtractPackageRecursive(handle, "", td.path, nullptr, nullptr);
+
+  // Make sure all the files are extracted correctly.
+  std::string path(td.path);
+  ASSERT_EQ(0, access((path + "/a.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b/c.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/b/d.txt").c_str(), F_OK));
+
+  // The content of the file is the same as expected.
+  std::string content1;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/a.txt", &content1));
+  ASSERT_EQ(kATxtContents, content1);
+
+  std::string content2;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/b/d.txt", &content2));
+  ASSERT_EQ(kDTxtContents, content2);
+
+  // Clean up the temp files under td.
+  ASSERT_EQ(0, unlink((path + "/a.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b/c.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/b/d.txt").c_str()));
+  ASSERT_EQ(0, rmdir((path + "/b").c_str()));
+
+  CloseArchive(handle);
+}
+
+TEST(ZipUtilTest, extract_prefix_with_slash) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Extract all the entries starting with "b/".
+  TemporaryDir td;
+  ExtractPackageRecursive(handle, "b/", td.path, nullptr, nullptr);
+
+  // Make sure all the files with "b/" prefix are extracted correctly.
+  std::string path(td.path);
+  ASSERT_EQ(0, access((path + "/c.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/d.txt").c_str(), F_OK));
+
+  // And the rest are not extracted.
+  ASSERT_EQ(-1, access((path + "/a.txt").c_str(), F_OK));
+  ASSERT_EQ(ENOENT, errno);
+  ASSERT_EQ(-1, access((path + "/b.txt").c_str(), F_OK));
+  ASSERT_EQ(ENOENT, errno);
+
+  // The content of the file is the same as expected.
+  std::string content1;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/c.txt", &content1));
+  ASSERT_EQ(kCTxtContents, content1);
+
+  std::string content2;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/d.txt", &content2));
+  ASSERT_EQ(kDTxtContents, content2);
+
+  // Clean up the temp files under td.
+  ASSERT_EQ(0, unlink((path + "/c.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/d.txt").c_str()));
+
+  CloseArchive(handle);
+}
+
+TEST(ZipUtilTest, extract_prefix_without_slash) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Extract all the file entries starting with "b/".
+  TemporaryDir td;
+  ExtractPackageRecursive(handle, "b", td.path, nullptr, nullptr);
+
+  // Make sure all the files with "b/" prefix are extracted correctly.
+  std::string path(td.path);
+  ASSERT_EQ(0, access((path + "/c.txt").c_str(), F_OK));
+  ASSERT_EQ(0, access((path + "/d.txt").c_str(), F_OK));
+
+  // And the rest are not extracted.
+  ASSERT_EQ(-1, access((path + "/a.txt").c_str(), F_OK));
+  ASSERT_EQ(ENOENT, errno);
+  ASSERT_EQ(-1, access((path + "/b.txt").c_str(), F_OK));
+  ASSERT_EQ(ENOENT, errno);
+
+  // The content of the file is the same as expected.
+  std::string content1;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/c.txt", &content1));
+  ASSERT_EQ(kCTxtContents, content1);
+
+  std::string content2;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/d.txt", &content2));
+  ASSERT_EQ(kDTxtContents, content2);
+
+  // Clean up the temp files under td.
+  ASSERT_EQ(0, unlink((path + "/c.txt").c_str()));
+  ASSERT_EQ(0, unlink((path + "/d.txt").c_str()));
+
+  CloseArchive(handle);
+}
+
+TEST(ZipUtilTest, set_timestamp) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
+
+  // Set the timestamp to 8/1/2008.
+  constexpr struct utimbuf timestamp = { 1217592000, 1217592000 };
+
+  // Extract all the entries starting with "b/".
+  TemporaryDir td;
+  ExtractPackageRecursive(handle, "b", td.path, &timestamp, nullptr);
+
+  // Make sure all the files with "b/" prefix are extracted correctly.
+  std::string path(td.path);
+  std::string file_c = path + "/c.txt";
+  std::string file_d = path + "/d.txt";
+  ASSERT_EQ(0, access(file_c.c_str(), F_OK));
+  ASSERT_EQ(0, access(file_d.c_str(), F_OK));
+
+  // Verify the timestamp.
+  timespec time;
+  time.tv_sec = 1217592000;
+  time.tv_nsec = 0;
+
+  struct stat sb;
+  ASSERT_EQ(0, stat(file_c.c_str(), &sb)) << strerror(errno);
+  ASSERT_EQ(time.tv_sec, static_cast<long>(sb.st_atime));
+  ASSERT_EQ(time.tv_sec, static_cast<long>(sb.st_mtime));
+
+  ASSERT_EQ(0, stat(file_d.c_str(), &sb)) << strerror(errno);
+  ASSERT_EQ(time.tv_sec, static_cast<long>(sb.st_atime));
+  ASSERT_EQ(time.tv_sec, static_cast<long>(sb.st_mtime));
+
+  // Clean up the temp files under td.
+  ASSERT_EQ(0, unlink(file_c.c_str()));
+  ASSERT_EQ(0, unlink(file_d.c_str()));
+
+  CloseArchive(handle);
+}
diff --git a/updater/install.cpp b/updater/install.cpp
index bfe91e7f..3c50a3fc 100644
--- a/updater/install.cpp
+++ b/updater/install.cpp
@@ -61,6 +61,7 @@
 #include "mounts.h"
 #include "ota_io.h"
 #include "otautil/DirUtil.h"
+#include "otautil/ZipUtil.h"
 #include "print_sha1.h"
 #include "tune2fs.h"
 #include "updater/updater.h"
@@ -356,6 +357,68 @@ Value* FormatFn(const char* name, State* state, const std::vector<std::unique_pt
   return nullptr;
 }
 
+// rename(src_name, dst_name)
+//   Renames src_name to dst_name. It automatically creates the necessary directories for dst_name.
+//   Example: rename("system/app/Hangouts/Hangouts.apk", "system/priv-app/Hangouts/Hangouts.apk")
+Value* RenameFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
+  if (argv.size() != 2) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() expects 2 args, got %zu", name, argv.size());
+  }
+
+  std::vector<std::string> args;
+  if (!ReadArgs(state, argv, &args)) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() Failed to parse the argument(s)", name);
+  }
+  const std::string& src_name = args[0];
+  const std::string& dst_name = args[1];
+
+  if (src_name.empty()) {
+    return ErrorAbort(state, kArgsParsingFailure, "src_name argument to %s() can't be empty", name);
+  }
+  if (dst_name.empty()) {
+    return ErrorAbort(state, kArgsParsingFailure, "dst_name argument to %s() can't be empty", name);
+  }
+  if (!make_parents(dst_name)) {
+    return ErrorAbort(state, kFileRenameFailure, "Creating parent of %s failed, error %s",
+                      dst_name.c_str(), strerror(errno));
+  } else if (access(dst_name.c_str(), F_OK) == 0 && access(src_name.c_str(), F_OK) != 0) {
+    // File was already moved
+    return StringValue(dst_name);
+  } else if (rename(src_name.c_str(), dst_name.c_str()) != 0) {
+    return ErrorAbort(state, kFileRenameFailure, "Rename of %s to %s failed, error %s",
+                      src_name.c_str(), dst_name.c_str(), strerror(errno));
+  }
+
+  return StringValue(dst_name);
+}
+
+// delete([filename, ...])
+//   Deletes all the filenames listed. Returns the number of files successfully deleted.
+//
+// delete_recursive([dirname, ...])
+//   Recursively deletes dirnames and all their contents. Returns the number of directories
+//   successfully deleted.
+Value* DeleteFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
+  std::vector<std::string> paths(argv.size());
+  for (size_t i = 0; i < argv.size(); ++i) {
+    if (!Evaluate(state, argv[i], &paths[i])) {
+      return nullptr;
+    }
+  }
+
+  bool recursive = (strcmp(name, "delete_recursive") == 0);
+
+  int success = 0;
+  for (size_t i = 0; i < argv.size(); ++i) {
+    if ((recursive ? dirUnlinkHierarchy(paths[i].c_str()) : unlink(paths[i].c_str())) == 0) {
+      ++success;
+    }
+  }
+
+  return StringValue(std::to_string(success));
+}
+
+
 Value* ShowProgressFn(const char* name, State* state,
                       const std::vector<std::unique_ptr<Expr>>& argv) {
   if (argv.size() != 2) {
@@ -410,6 +473,36 @@ Value* SetProgressFn(const char* name, State* state, const std::vector<std::uniq
   return StringValue(frac_str);
 }
 
+// package_extract_dir(package_dir, dest_dir)
+//   Extracts all files from the package underneath package_dir and writes them to the
+//   corresponding tree beneath dest_dir. Any existing files are overwritten.
+//   Example: package_extract_dir("system", "/system")
+//
+//   Note: package_dir needs to be a relative path; dest_dir needs to be an absolute path.
+Value* PackageExtractDirFn(const char* name, State* state,
+                           const std::vector<std::unique_ptr<Expr>>&argv) {
+  if (argv.size() != 2) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() expects 2 args, got %zu", name,
+                      argv.size());
+  }
+
+  std::vector<std::string> args;
+  if (!ReadArgs(state, argv, &args)) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() Failed to parse the argument(s)", name);
+  }
+  const std::string& zip_path = args[0];
+  const std::string& dest_path = args[1];
+
+  ZipArchiveHandle za = static_cast<UpdaterInfo*>(state->cookie)->package_zip;
+
+  // To create a consistent system image, never use the clock for timestamps.
+  constexpr struct utimbuf timestamp = { 1217592000, 1217592000 };  // 8/1/2008 default
+
+  bool success = ExtractPackageRecursive(za, zip_path, dest_path, &timestamp, sehandle);
+
+  return StringValue(success ? "t" : "");
+}
+
 // package_extract_file(package_file[, dest_file])
 //   Extracts a single package_file from the update package and writes it to dest_file,
 //   overwriting existing files if necessary. Without the dest_file argument, returns the
@@ -497,6 +590,288 @@ Value* PackageExtractFileFn(const char* name, State* state,
   }
 }
 
+// symlink(target, [src1, src2, ...])
+//   Creates all sources as symlinks to target. It unlinks any previously existing src1, src2, etc
+//   before creating symlinks.
+Value* SymlinkFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
+  if (argv.size() == 0) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() expects 1+ args, got %zu", name, argv.size());
+  }
+  std::string target;
+  if (!Evaluate(state, argv[0], &target)) {
+    return nullptr;
+  }
+
+  std::vector<std::string> srcs;
+  if (!ReadArgs(state, argv, &srcs, 1, argv.size() - 1)) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s(): Failed to parse the argument(s)", name);
+  }
+
+  size_t bad = 0;
+  for (const auto& src : srcs) {
+    if (unlink(src.c_str()) == -1 && errno != ENOENT) {
+      PLOG(ERROR) << name << ": failed to remove " << src;
+      ++bad;
+    } else if (!make_parents(src)) {
+      LOG(ERROR) << name << ": failed to symlink " << src << " to " << target
+                 << ": making parents failed";
+      ++bad;
+    } else if (symlink(target.c_str(), src.c_str()) == -1) {
+      PLOG(ERROR) << name << ": failed to symlink " << src << " to " << target;
+      ++bad;
+    }
+  }
+  if (bad != 0) {
+    return ErrorAbort(state, kSymlinkFailure, "%s: Failed to create %zu symlink(s)", name, bad);
+  }
+  return StringValue("t");
+}
+
+struct perm_parsed_args {
+  bool has_uid;
+  uid_t uid;
+  bool has_gid;
+  gid_t gid;
+  bool has_mode;
+  mode_t mode;
+  bool has_fmode;
+  mode_t fmode;
+  bool has_dmode;
+  mode_t dmode;
+  bool has_selabel;
+  const char* selabel;
+  bool has_capabilities;
+  uint64_t capabilities;
+};
+
+static struct perm_parsed_args ParsePermArgs(State * state,
+                                             const std::vector<std::string>& args) {
+  struct perm_parsed_args parsed;
+  int bad = 0;
+  static int max_warnings = 20;
+
+  memset(&parsed, 0, sizeof(parsed));
+
+  for (size_t i = 1; i < args.size(); i += 2) {
+    if (args[i] == "uid") {
+      int64_t uid;
+      if (sscanf(args[i + 1].c_str(), "%" SCNd64, &uid) == 1) {
+        parsed.uid = uid;
+        parsed.has_uid = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid UID \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "gid") {
+      int64_t gid;
+      if (sscanf(args[i + 1].c_str(), "%" SCNd64, &gid) == 1) {
+        parsed.gid = gid;
+        parsed.has_gid = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid GID \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "mode") {
+      int32_t mode;
+      if (sscanf(args[i + 1].c_str(), "%" SCNi32, &mode) == 1) {
+        parsed.mode = mode;
+        parsed.has_mode = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid mode \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "dmode") {
+      int32_t mode;
+      if (sscanf(args[i + 1].c_str(), "%" SCNi32, &mode) == 1) {
+        parsed.dmode = mode;
+        parsed.has_dmode = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid dmode \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "fmode") {
+      int32_t mode;
+      if (sscanf(args[i + 1].c_str(), "%" SCNi32, &mode) == 1) {
+        parsed.fmode = mode;
+        parsed.has_fmode = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid fmode \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "capabilities") {
+      int64_t capabilities;
+      if (sscanf(args[i + 1].c_str(), "%" SCNi64, &capabilities) == 1) {
+        parsed.capabilities = capabilities;
+        parsed.has_capabilities = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid capabilities \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (args[i] == "selabel") {
+      if (!args[i + 1].empty()) {
+        parsed.selabel = args[i + 1].c_str();
+        parsed.has_selabel = true;
+      } else {
+        uiPrintf(state, "ParsePermArgs: invalid selabel \"%s\"\n", args[i + 1].c_str());
+        bad++;
+      }
+      continue;
+    }
+    if (max_warnings != 0) {
+      printf("ParsedPermArgs: unknown key \"%s\", ignoring\n", args[i].c_str());
+      max_warnings--;
+      if (max_warnings == 0) {
+        LOG(INFO) << "ParsedPermArgs: suppressing further warnings";
+      }
+    }
+  }
+  return parsed;
+}
+
+static int ApplyParsedPerms(State* state, const char* filename, const struct stat* statptr,
+                            struct perm_parsed_args parsed) {
+  int bad = 0;
+
+  if (parsed.has_selabel) {
+    if (lsetfilecon(filename, parsed.selabel) != 0) {
+      uiPrintf(state, "ApplyParsedPerms: lsetfilecon of %s to %s failed: %s\n", filename,
+               parsed.selabel, strerror(errno));
+      bad++;
+    }
+  }
+
+  /* ignore symlinks */
+  if (S_ISLNK(statptr->st_mode)) {
+    return bad;
+  }
+
+  if (parsed.has_uid) {
+    if (chown(filename, parsed.uid, -1) < 0) {
+      uiPrintf(state, "ApplyParsedPerms: chown of %s to %d failed: %s\n", filename, parsed.uid,
+               strerror(errno));
+      bad++;
+    }
+  }
+
+  if (parsed.has_gid) {
+    if (chown(filename, -1, parsed.gid) < 0) {
+      uiPrintf(state, "ApplyParsedPerms: chgrp of %s to %d failed: %s\n", filename, parsed.gid,
+               strerror(errno));
+      bad++;
+    }
+  }
+
+  if (parsed.has_mode) {
+    if (chmod(filename, parsed.mode) < 0) {
+      uiPrintf(state, "ApplyParsedPerms: chmod of %s to %d failed: %s\n", filename, parsed.mode,
+               strerror(errno));
+      bad++;
+    }
+  }
+
+  if (parsed.has_dmode && S_ISDIR(statptr->st_mode)) {
+    if (chmod(filename, parsed.dmode) < 0) {
+      uiPrintf(state, "ApplyParsedPerms: chmod of %s to %d failed: %s\n", filename, parsed.dmode,
+               strerror(errno));
+      bad++;
+    }
+  }
+
+  if (parsed.has_fmode && S_ISREG(statptr->st_mode)) {
+    if (chmod(filename, parsed.fmode) < 0) {
+      uiPrintf(state, "ApplyParsedPerms: chmod of %s to %d failed: %s\n", filename, parsed.fmode,
+               strerror(errno));
+      bad++;
+    }
+  }
+
+  if (parsed.has_capabilities && S_ISREG(statptr->st_mode)) {
+    if (parsed.capabilities == 0) {
+      if ((removexattr(filename, XATTR_NAME_CAPS) == -1) && (errno != ENODATA)) {
+        // Report failure unless it's ENODATA (attribute not set)
+        uiPrintf(state, "ApplyParsedPerms: removexattr of %s to %" PRIx64 " failed: %s\n", filename,
+                 parsed.capabilities, strerror(errno));
+        bad++;
+      }
+    } else {
+      struct vfs_cap_data cap_data;
+      memset(&cap_data, 0, sizeof(cap_data));
+      cap_data.magic_etc = VFS_CAP_REVISION | VFS_CAP_FLAGS_EFFECTIVE;
+      cap_data.data[0].permitted = (uint32_t)(parsed.capabilities & 0xffffffff);
+      cap_data.data[0].inheritable = 0;
+      cap_data.data[1].permitted = (uint32_t)(parsed.capabilities >> 32);
+      cap_data.data[1].inheritable = 0;
+      if (setxattr(filename, XATTR_NAME_CAPS, &cap_data, sizeof(cap_data), 0) < 0) {
+        uiPrintf(state, "ApplyParsedPerms: setcap of %s to %" PRIx64 " failed: %s\n", filename,
+                 parsed.capabilities, strerror(errno));
+        bad++;
+      }
+    }
+  }
+
+  return bad;
+}
+
+// nftw doesn't allow us to pass along context, so we need to use
+// global variables.  *sigh*
+static struct perm_parsed_args recursive_parsed_args;
+static State* recursive_state;
+
+static int do_SetMetadataRecursive(const char* filename, const struct stat* statptr, int fileflags,
+                                   struct FTW* pfwt) {
+  return ApplyParsedPerms(recursive_state, filename, statptr, recursive_parsed_args);
+}
+
+static Value* SetMetadataFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
+  if ((argv.size() % 2) != 1) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() expects an odd number of arguments, got %zu",
+                      name, argv.size());
+  }
+
+  std::vector<std::string> args;
+  if (!ReadArgs(state, argv, &args)) {
+    return ErrorAbort(state, kArgsParsingFailure, "%s() Failed to parse the argument(s)", name);
+  }
+
+  struct stat sb;
+  if (lstat(args[0].c_str(), &sb) == -1) {
+    return ErrorAbort(state, kSetMetadataFailure, "%s: Error on lstat of \"%s\": %s", name,
+                      args[0].c_str(), strerror(errno));
+  }
+
+  struct perm_parsed_args parsed = ParsePermArgs(state, args);
+  int bad = 0;
+  bool recursive = (strcmp(name, "set_metadata_recursive") == 0);
+
+  if (recursive) {
+    recursive_parsed_args = parsed;
+    recursive_state = state;
+    bad += nftw(args[0].c_str(), do_SetMetadataRecursive, 30, FTW_CHDIR | FTW_DEPTH | FTW_PHYS);
+    memset(&recursive_parsed_args, 0, sizeof(recursive_parsed_args));
+    recursive_state = NULL;
+  } else {
+    bad += ApplyParsedPerms(state, args[0].c_str(), &sb, parsed);
+  }
+
+  if (bad > 0) {
+    return ErrorAbort(state, kSetMetadataFailure, "%s: some changes failed", name);
+  }
+
+  return StringValue("");
+}
+
 Value* GetPropFn(const char* name, State* state, const std::vector<std::unique_ptr<Expr>>& argv) {
   if (argv.size() != 1) {
     return ErrorAbort(state, kArgsParsingFailure, "%s() expects 1 arg, got %zu", name, argv.size());
@@ -1028,7 +1403,25 @@ void RegisterInstallFunctions() {
   RegisterFunction("format", FormatFn);
   RegisterFunction("show_progress", ShowProgressFn);
   RegisterFunction("set_progress", SetProgressFn);
+  RegisterFunction("delete", DeleteFn);
+  RegisterFunction("delete_recursive", DeleteFn);
+  RegisterFunction("package_extract_dir", PackageExtractDirFn);
   RegisterFunction("package_extract_file", PackageExtractFileFn);
+  RegisterFunction("symlink", SymlinkFn);
+
+  // Usage:
+  //   set_metadata("filename", "key1", "value1", "key2", "value2", ...)
+  // Example:
+  //   set_metadata("/system/bin/netcfg", "uid", 0, "gid", 3003, "mode", 02750, "selabel",
+  //                "u:object_r:system_file:s0", "capabilities", 0x0);
+  RegisterFunction("set_metadata", SetMetadataFn);
+
+  // Usage:
+  //   set_metadata_recursive("dirname", "key1", "value1", "key2", "value2", ...)
+  // Example:
+  //   set_metadata_recursive("/system", "uid", 0, "gid", 0, "fmode", 0644, "dmode", 0755,
+  //                          "selabel", "u:object_r:system_file:s0", "capabilities", 0x0);
+  RegisterFunction("set_metadata_recursive", SetMetadataFn);
 
   RegisterFunction("getprop", GetPropFn);
   RegisterFunction("file_getprop", FileGetPropFn);
@@ -1041,6 +1434,7 @@ void RegisterInstallFunctions() {
 
   RegisterFunction("read_file", ReadFileFn);
   RegisterFunction("sha1_check", Sha1CheckFn);
+  RegisterFunction("rename", RenameFn);
   RegisterFunction("write_value", WriteValueFn);
 
   RegisterFunction("wipe_cache", WipeCacheFn);