/*
 * Copyright (C) 2010 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.
 */

package com.android.internal.content;

import static android.content.pm.PackageManager.INSTALL_FAILED_NO_MATCHING_ABIS;
import static android.content.pm.PackageManager.INSTALL_SUCCEEDED;
import static android.content.pm.PackageManager.NO_NATIVE_LIBRARIES;
import static android.system.OsConstants.S_IRGRP;
import static android.system.OsConstants.S_IROTH;
import static android.system.OsConstants.S_IRWXU;
import static android.system.OsConstants.S_IXGRP;
import static android.system.OsConstants.S_IXOTH;

import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageParser;
import android.content.pm.PackageParser.Package;
import android.content.pm.PackageParser.PackageLite;
import android.content.pm.PackageParser.PackageParserException;
import android.os.Build;
import android.os.SELinux;
import android.os.SystemProperties;
import android.system.ErrnoException;
import android.system.Os;
import android.util.Slog;

import dalvik.system.CloseGuard;
import dalvik.system.VMRuntime;

import java.io.Closeable;
import java.io.File;
import java.io.FileDescriptor;
import java.io.IOException;
import java.util.List;

Native libraries helper.
@hide
/**
 * Native libraries helper.
 *
 * @hide
 */
public class NativeLibraryHelper {
    private static final String TAG = "NativeHelper";
    private static final boolean DEBUG_NATIVE = false;

    public static final String LIB_DIR_NAME = "lib";
    public static final String LIB64_DIR_NAME = "lib64";

    // Special value for {@code PackageParser.Package#cpuAbiOverride} to indicate
    // that the cpuAbiOverride must be clear.
    public static final String CLEAR_ABI_OVERRIDE = "-";

    
A handle to an opened package, consisting of one or more APKs. Used as
input to the various NativeLibraryHelper methods. Allows us to scan and
parse the APKs exactly once instead of doing it multiple times.
@hide
/**
     * A handle to an opened package, consisting of one or more APKs. Used as
     * input to the various NativeLibraryHelper methods. Allows us to scan and
     * parse the APKs exactly once instead of doing it multiple times.
     *
     * @hide
     */
    public static class Handle implements Closeable {
        private final CloseGuard mGuard = CloseGuard.get();
        private volatile boolean mClosed;

        final long[] apkHandles;
        final boolean multiArch;
        final boolean extractNativeLibs;
        final boolean debuggable;

        public static Handle create(File packageFile) throws IOException {
            try {
                final PackageLite lite = PackageParser.parsePackageLite(packageFile, 0);
                return create(lite);
            } catch (PackageParserException e) {
                throw new IOException("Failed to parse package: " + packageFile, e);
            }
        }

        public static Handle create(Package pkg) throws IOException {
            return create(pkg.getAllCodePaths(),
                    (pkg.applicationInfo.flags & ApplicationInfo.FLAG_MULTIARCH) != 0,
                    (pkg.applicationInfo.flags & ApplicationInfo.FLAG_EXTRACT_NATIVE_LIBS) != 0,
                    (pkg.applicationInfo.flags & ApplicationInfo.FLAG_DEBUGGABLE) != 0);
        }

        public static Handle create(PackageLite lite) throws IOException {
            return create(lite.getAllCodePaths(), lite.multiArch, lite.extractNativeLibs,
                    lite.debuggable);
        }

        private static Handle create(List<String> codePaths, boolean multiArch,
                boolean extractNativeLibs, boolean debuggable) throws IOException {
            final int size = codePaths.size();
            final long[] apkHandles = new long[size];
            for (int i = 0; i < size; i++) {
                final String path = codePaths.get(i);
                apkHandles[i] = nativeOpenApk(path);
                if (apkHandles[i] == 0) {
                    // Unwind everything we've opened so far
                    for (int j = 0; j < i; j++) {
                        nativeClose(apkHandles[j]);
                    }
                    throw new IOException("Unable to open APK: " + path);
                }
            }

            return new Handle(apkHandles, multiArch, extractNativeLibs, debuggable);
        }

        public static Handle createFd(PackageLite lite, FileDescriptor fd) throws IOException {
            final long[] apkHandles = new long[1];
            final String path = lite.baseCodePath;
            apkHandles[0] = nativeOpenApkFd(fd, path);
            if (apkHandles[0] == 0) {
                throw new IOException("Unable to open APK " + path + " from fd " + fd);
            }

            return new Handle(apkHandles, lite.multiArch, lite.extractNativeLibs, lite.debuggable);
        }

        Handle(long[] apkHandles, boolean multiArch, boolean extractNativeLibs,
                boolean debuggable) {
            this.apkHandles = apkHandles;
            this.multiArch = multiArch;
            this.extractNativeLibs = extractNativeLibs;
            this.debuggable = debuggable;
            mGuard.open("close");
        }

        @Override
        public void close() {
            for (long apkHandle : apkHandles) {
                nativeClose(apkHandle);
            }
            mGuard.close();
            mClosed = true;
        }

        @Override
        protected void finalize() throws Throwable {
            if (mGuard != null) {
                mGuard.warnIfOpen();
            }
            try {
                if (!mClosed) {
                    close();
                }
            } finally {
                super.finalize();
            }
        }
    }

    private static native long nativeOpenApk(String path);
    private static native long nativeOpenApkFd(FileDescriptor fd, String debugPath);
    private static native void nativeClose(long handle);

    private static native long nativeSumNativeBinaries(long handle, String cpuAbi,
            boolean debuggable);

    private native static int nativeCopyNativeBinaries(long handle, String sharedLibraryPath,
            String abiToCopy, boolean extractNativeLibs, boolean hasNativeBridge,
            boolean debuggable);

    private static long sumNativeBinaries(Handle handle, String abi) {
        long sum = 0;
        for (long apkHandle : handle.apkHandles) {
            sum += nativeSumNativeBinaries(apkHandle, abi, handle.debuggable);
        }
        return sum;
    }

    
Copies native binaries to a shared library directory.
Params:
handle – APK file to scan for native libraries
sharedLibraryDir – directory for libraries to be copied to
Returns:
PackageManager.INSTALL_SUCCEEDED if successful or another error code from that class if not/**
     * Copies native binaries to a shared library directory.
     *
     * @param handle APK file to scan for native libraries
     * @param sharedLibraryDir directory for libraries to be copied to
     * @return {@link PackageManager#INSTALL_SUCCEEDED} if successful or another
     *         error code from that class if not
     */
    public static int copyNativeBinaries(Handle handle, File sharedLibraryDir, String abi) {
        for (long apkHandle : handle.apkHandles) {
            int res = nativeCopyNativeBinaries(apkHandle, sharedLibraryDir.getPath(), abi,
                    handle.extractNativeLibs, HAS_NATIVE_BRIDGE, handle.debuggable);
            if (res != INSTALL_SUCCEEDED) {
                return res;
            }
        }
        return INSTALL_SUCCEEDED;
    }

    
Checks if a given APK contains native code for any of the provided supportedAbis. Returns an index into supportedAbis if a matching ABI is found, PackageManager.NO_NATIVE_LIBRARIES if the APK doesn't contain any native code, and PackageManager.INSTALL_FAILED_NO_MATCHING_ABIS if none of the ABIs match. /**
     * Checks if a given APK contains native code for any of the provided
     * {@code supportedAbis}. Returns an index into {@code supportedAbis} if a matching
     * ABI is found, {@link PackageManager#NO_NATIVE_LIBRARIES} if the
     * APK doesn't contain any native code, and
     * {@link PackageManager#INSTALL_FAILED_NO_MATCHING_ABIS} if none of the ABIs match.
     */
    public static int findSupportedAbi(Handle handle, String[] supportedAbis) {
        int finalRes = NO_NATIVE_LIBRARIES;
        for (long apkHandle : handle.apkHandles) {
            final int res = nativeFindSupportedAbi(apkHandle, supportedAbis, handle.debuggable);
            if (res == NO_NATIVE_LIBRARIES) {
                // No native code, keep looking through all APKs.
            } else if (res == INSTALL_FAILED_NO_MATCHING_ABIS) {
                // Found some native code, but no ABI match; update our final
                // result if we haven't found other valid code.
                if (finalRes < 0) {
                    finalRes = INSTALL_FAILED_NO_MATCHING_ABIS;
                }
            } else if (res >= 0) {
                // Found valid native code, track the best ABI match
                if (finalRes < 0 || res < finalRes) {
                    finalRes = res;
                }
            } else {
                // Unexpected error; bail
                return res;
            }
        }
        return finalRes;
    }

    private native static int nativeFindSupportedAbi(long handle, String[] supportedAbis,
            boolean debuggable);

    // Convenience method to call removeNativeBinariesFromDirLI(File)
    public static void removeNativeBinariesLI(String nativeLibraryPath) {
        if (nativeLibraryPath == null) return;
        removeNativeBinariesFromDirLI(new File(nativeLibraryPath), false /* delete root dir */);
    }

    
Remove the native binaries of a given package. This deletes the files
/**
     * Remove the native binaries of a given package. This deletes the files
     */
    public static void removeNativeBinariesFromDirLI(File nativeLibraryRoot,
            boolean deleteRootDir) {
        if (DEBUG_NATIVE) {
            Slog.w(TAG, "Deleting native binaries from: " + nativeLibraryRoot.getPath());
        }

        /*
         * Just remove any file in the directory. Since the directory is owned
         * by the 'system' UID, the application is not supposed to have written
         * anything there.
         */
        if (nativeLibraryRoot.exists()) {
            final File[] files = nativeLibraryRoot.listFiles();
            if (files != null) {
                for (int nn = 0; nn < files.length; nn++) {
                    if (DEBUG_NATIVE) {
                        Slog.d(TAG, "    Deleting " + files[nn].getName());
                    }

                    if (files[nn].isDirectory()) {
                        removeNativeBinariesFromDirLI(files[nn], true /* delete root dir */);
                    } else if (!files[nn].delete()) {
                        Slog.w(TAG, "Could not delete native binary: " + files[nn].getPath());
                    }
                }
            }
            // Do not delete 'lib' directory itself, unless we're specifically
            // asked to or this will prevent installation of future updates.
            if (deleteRootDir) {
                if (!nativeLibraryRoot.delete()) {
                    Slog.w(TAG, "Could not delete native binary directory: " +
                            nativeLibraryRoot.getPath());
                }
            }
        }
    }

    
@hide
/**
     * @hide
     */
    public static void createNativeLibrarySubdir(File path) throws IOException {
        if (!path.isDirectory()) {
            path.delete();

            if (!path.mkdir()) {
                throw new IOException("Cannot create " + path.getPath());
            }

            try {
                Os.chmod(path.getPath(), S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
            } catch (ErrnoException e) {
                throw new IOException("Cannot chmod native library directory "
                        + path.getPath(), e);
            }
        } else if (!SELinux.restorecon(path)) {
            throw new IOException("Cannot set SELinux context for " + path.getPath());
        }
    }

    private static long sumNativeBinariesForSupportedAbi(Handle handle, String[] abiList) {
        int abi = findSupportedAbi(handle, abiList);
        if (abi >= 0) {
            return sumNativeBinaries(handle, abiList[abi]);
        } else {
            return 0;
        }
    }

    public static int copyNativeBinariesForSupportedAbi(Handle handle, File libraryRoot,
            String[] abiList, boolean useIsaSubdir) throws IOException {
        createNativeLibrarySubdir(libraryRoot);

        /*
         * If this is an internal application or our nativeLibraryPath points to
         * the app-lib directory, unpack the libraries if necessary.
         */
        int abi = findSupportedAbi(handle, abiList);
        if (abi >= 0) {
            /*
             * If we have a matching instruction set, construct a subdir under the native
             * library root that corresponds to this instruction set.
             */
            final String instructionSet = VMRuntime.getInstructionSet(abiList[abi]);
            final File subDir;
            if (useIsaSubdir) {
                final File isaSubdir = new File(libraryRoot, instructionSet);
                createNativeLibrarySubdir(isaSubdir);
                subDir = isaSubdir;
            } else {
                subDir = libraryRoot;
            }

            int copyRet = copyNativeBinaries(handle, subDir, abiList[abi]);
            if (copyRet != PackageManager.INSTALL_SUCCEEDED) {
                return copyRet;
            }
        }

        return abi;
    }

    public static int copyNativeBinariesWithOverride(Handle handle, File libraryRoot,
            String abiOverride) {
        try {
            if (handle.multiArch) {
                // Warn if we've set an abiOverride for multi-lib packages..
                // By definition, we need to copy both 32 and 64 bit libraries for
                // such packages.
                if (abiOverride != null && !CLEAR_ABI_OVERRIDE.equals(abiOverride)) {
                    Slog.w(TAG, "Ignoring abiOverride for multi arch application.");
                }

                int copyRet = PackageManager.NO_NATIVE_LIBRARIES;
                if (Build.SUPPORTED_32_BIT_ABIS.length > 0) {
                    copyRet = copyNativeBinariesForSupportedAbi(handle, libraryRoot,
                            Build.SUPPORTED_32_BIT_ABIS, true /* use isa specific subdirs */);
                    if (copyRet < 0 && copyRet != PackageManager.NO_NATIVE_LIBRARIES &&
                            copyRet != PackageManager.INSTALL_FAILED_NO_MATCHING_ABIS) {
                        Slog.w(TAG, "Failure copying 32 bit native libraries; copyRet=" +copyRet);
                        return copyRet;
                    }
                }

                if (Build.SUPPORTED_64_BIT_ABIS.length > 0) {
                    copyRet = copyNativeBinariesForSupportedAbi(handle, libraryRoot,
                            Build.SUPPORTED_64_BIT_ABIS, true /* use isa specific subdirs */);
                    if (copyRet < 0 && copyRet != PackageManager.NO_NATIVE_LIBRARIES &&
                            copyRet != PackageManager.INSTALL_FAILED_NO_MATCHING_ABIS) {
                        Slog.w(TAG, "Failure copying 64 bit native libraries; copyRet=" +copyRet);
                        return copyRet;
                    }
                }
            } else {
                String cpuAbiOverride = null;
                if (CLEAR_ABI_OVERRIDE.equals(abiOverride)) {
                    cpuAbiOverride = null;
                } else if (abiOverride != null) {
                    cpuAbiOverride = abiOverride;
                }

                String[] abiList = (cpuAbiOverride != null) ?
                        new String[] { cpuAbiOverride } : Build.SUPPORTED_ABIS;
                if (Build.SUPPORTED_64_BIT_ABIS.length > 0 && cpuAbiOverride == null &&
                        hasRenderscriptBitcode(handle)) {
                    abiList = Build.SUPPORTED_32_BIT_ABIS;
                }

                int copyRet = copyNativeBinariesForSupportedAbi(handle, libraryRoot, abiList,
                        true /* use isa specific subdirs */);
                if (copyRet < 0 && copyRet != PackageManager.NO_NATIVE_LIBRARIES) {
                    Slog.w(TAG, "Failure copying native libraries [errorCode=" + copyRet + "]");
                    return copyRet;
                }
            }

            return PackageManager.INSTALL_SUCCEEDED;
        } catch (IOException e) {
            Slog.e(TAG, "Copying native libraries failed", e);
            return PackageManager.INSTALL_FAILED_INTERNAL_ERROR;
        }
    }

    public static long sumNativeBinariesWithOverride(Handle handle, String abiOverride)
            throws IOException {
        long sum = 0;
        if (handle.multiArch) {
            // Warn if we've set an abiOverride for multi-lib packages..
            // By definition, we need to copy both 32 and 64 bit libraries for
            // such packages.
            if (abiOverride != null && !CLEAR_ABI_OVERRIDE.equals(abiOverride)) {
                Slog.w(TAG, "Ignoring abiOverride for multi arch application.");
            }

            if (Build.SUPPORTED_32_BIT_ABIS.length > 0) {
                sum += sumNativeBinariesForSupportedAbi(handle, Build.SUPPORTED_32_BIT_ABIS);
            }

            if (Build.SUPPORTED_64_BIT_ABIS.length > 0) {
                sum += sumNativeBinariesForSupportedAbi(handle, Build.SUPPORTED_64_BIT_ABIS);
            }
        } else {
            String cpuAbiOverride = null;
            if (CLEAR_ABI_OVERRIDE.equals(abiOverride)) {
                cpuAbiOverride = null;
            } else if (abiOverride != null) {
                cpuAbiOverride = abiOverride;
            }

            String[] abiList = (cpuAbiOverride != null) ?
                    new String[] { cpuAbiOverride } : Build.SUPPORTED_ABIS;
            if (Build.SUPPORTED_64_BIT_ABIS.length > 0 && cpuAbiOverride == null &&
                    hasRenderscriptBitcode(handle)) {
                abiList = Build.SUPPORTED_32_BIT_ABIS;
            }

            sum += sumNativeBinariesForSupportedAbi(handle, abiList);
        }
        return sum;
    }

    // We don't care about the other return values for now.
    private static final int BITCODE_PRESENT = 1;

    private static final boolean HAS_NATIVE_BRIDGE =
            !"0".equals(SystemProperties.get("ro.dalvik.vm.native.bridge", "0"));

    private static native int hasRenderscriptBitcode(long apkHandle);

    public static boolean hasRenderscriptBitcode(Handle handle) throws IOException {
        for (long apkHandle : handle.apkHandles) {
            final int res = hasRenderscriptBitcode(apkHandle);
            if (res < 0) {
                throw new IOException("Error scanning APK, code: " + res);
            } else if (res == BITCODE_PRESENT) {
                return true;
            }
        }
        return false;
    }
}