| /* |
| * Copyright (C) 2012 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 android.content.pm; |
| |
| import android.annotation.SystemApi; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| import android.util.Slog; |
| |
| import java.io.BufferedInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.security.DigestInputStream; |
| import java.security.MessageDigest; |
| import java.security.NoSuchAlgorithmException; |
| import java.util.Arrays; |
| |
| import libcore.io.IoUtils; |
| |
| /** |
| * Represents the manifest digest for a package. This is suitable for comparison |
| * of two packages to know whether the manifests are identical. |
| * |
| * @hide |
| */ |
| @SystemApi |
| public class ManifestDigest implements Parcelable { |
| private static final String TAG = "ManifestDigest"; |
| |
| /** The digest of the manifest in our preferred order. */ |
| private final byte[] mDigest; |
| |
| /** What we print out first when toString() is called. */ |
| private static final String TO_STRING_PREFIX = "ManifestDigest {mDigest="; |
| |
| /** Digest algorithm to use. */ |
| private static final String DIGEST_ALGORITHM = "SHA-256"; |
| |
| ManifestDigest(byte[] digest) { |
| mDigest = digest; |
| } |
| |
| private ManifestDigest(Parcel source) { |
| mDigest = source.createByteArray(); |
| } |
| |
| static ManifestDigest fromInputStream(InputStream fileIs) { |
| if (fileIs == null) { |
| return null; |
| } |
| |
| final MessageDigest md; |
| try { |
| md = MessageDigest.getInstance(DIGEST_ALGORITHM); |
| } catch (NoSuchAlgorithmException e) { |
| throw new RuntimeException(DIGEST_ALGORITHM + " must be available", e); |
| } |
| |
| final DigestInputStream dis = new DigestInputStream(new BufferedInputStream(fileIs), md); |
| try { |
| byte[] readBuffer = new byte[8192]; |
| while (dis.read(readBuffer, 0, readBuffer.length) != -1) { |
| // not using |
| } |
| } catch (IOException e) { |
| Slog.w(TAG, "Could not read manifest"); |
| return null; |
| } finally { |
| IoUtils.closeQuietly(dis); |
| } |
| |
| final byte[] digest = md.digest(); |
| return new ManifestDigest(digest); |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (!(o instanceof ManifestDigest)) { |
| return false; |
| } |
| |
| final ManifestDigest other = (ManifestDigest) o; |
| |
| return this == other || Arrays.equals(mDigest, other.mDigest); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Arrays.hashCode(mDigest); |
| } |
| |
| @Override |
| public String toString() { |
| final StringBuilder sb = new StringBuilder(TO_STRING_PREFIX.length() |
| + (mDigest.length * 3) + 1); |
| |
| sb.append(TO_STRING_PREFIX); |
| |
| final int N = mDigest.length; |
| for (int i = 0; i < N; i++) { |
| final byte b = mDigest[i]; |
| IntegralToString.appendByteAsHex(sb, b, false); |
| sb.append(','); |
| } |
| sb.append('}'); |
| |
| return sb.toString(); |
| } |
| |
| @Override |
| public void writeToParcel(Parcel dest, int flags) { |
| dest.writeByteArray(mDigest); |
| } |
| |
| public static final Parcelable.Creator<ManifestDigest> CREATOR |
| = new Parcelable.Creator<ManifestDigest>() { |
| public ManifestDigest createFromParcel(Parcel source) { |
| return new ManifestDigest(source); |
| } |
| |
| public ManifestDigest[] newArray(int size) { |
| return new ManifestDigest[size]; |
| } |
| }; |
| |
| } |