open-keychain/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/ComparableS2K.java
2016-02-10 17:36:02 +01:00

122 lines
4 KiB
Java

/*
* Copyright (C) 2016 Vincent Breitmoser <look@my.amazin.horse>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.sufficientlysecure.keychain.pgp;
import java.util.Arrays;
import android.os.Parcel;
import android.os.Parcelable;
import org.bouncycastle.bcpg.S2K;
/** This is an immutable and parcelable class which stores the full s2k parametrization
* of an encrypted secret key, i.e. all fields of the {@link S2K} class (type, hash algo,
* iteration count, iv) plus the encryptionAlgorithm. This class is intended to be used
* as key in a HashMap for session key caching purposes, and overrides the
* {@link #hashCode} and {@link #equals} methods in a suitable way.
*
* Note that although it is a rather unlikely scenario that secret keys of the same key
* are encrypted with different ciphers, the encryption algorithm still determines the
* length of the specific session key and thus needs to be considered for purposes of
* session key caching.
*
* @see org.bouncycastle.bcpg.S2K
*/
public class ComparableS2K implements Parcelable {
private final int encryptionAlgorithm;
private final int s2kType;
private final int s2kHashAlgo;
private final long s2kItCount;
private final byte[] s2kIV;
Integer cachedHashCode;
public ComparableS2K(int encryptionAlgorithm, S2K s2k) {
this.encryptionAlgorithm = encryptionAlgorithm;
this.s2kType = s2k.getType();
this.s2kHashAlgo = s2k.getHashAlgorithm();
this.s2kItCount = s2k.getIterationCount();
this.s2kIV = s2k.getIV();
}
protected ComparableS2K(Parcel in) {
encryptionAlgorithm = in.readInt();
s2kType = in.readInt();
s2kHashAlgo = in.readInt();
s2kItCount = in.readLong();
s2kIV = in.createByteArray();
}
@Override
public int hashCode() {
if (cachedHashCode == null) {
cachedHashCode = encryptionAlgorithm;
cachedHashCode = 31 * cachedHashCode + s2kType;
cachedHashCode = 31 * cachedHashCode + s2kHashAlgo;
cachedHashCode = 31 * cachedHashCode + (int) (s2kItCount ^ (s2kItCount >>> 32));
cachedHashCode = 31 * cachedHashCode + Arrays.hashCode(s2kIV);
}
return cachedHashCode;
}
@Override
public boolean equals(Object o) {
boolean isComparableS2K = o instanceof ComparableS2K;
if (!isComparableS2K) {
return false;
}
ComparableS2K other = (ComparableS2K) o;
return encryptionAlgorithm == other.encryptionAlgorithm
&& s2kType == other.s2kType
&& s2kHashAlgo == other.s2kHashAlgo
&& s2kItCount == other.s2kItCount
&& Arrays.equals(s2kIV, other.s2kIV);
}
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(encryptionAlgorithm);
dest.writeInt(s2kType);
dest.writeInt(s2kHashAlgo);
dest.writeLong(s2kItCount);
dest.writeByteArray(s2kIV);
}
public static final Creator<ComparableS2K> CREATOR = new Creator<ComparableS2K>() {
@Override
public ComparableS2K createFromParcel(Parcel in) {
return new ComparableS2K(in);
}
@Override
public ComparableS2K[] newArray(int size) {
return new ComparableS2K[size];
}
};
}