/*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package sun.security.krb5.internal;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import sun.security.krb5.*;
import sun.security.krb5.internal.crypto.KeyUsage;
import sun.security.krb5.internal.util.KerberosString;
import sun.security.util.DerOutputStream;
import sun.security.util.DerValue;
/**
* Implements the ASN.1 PA-FOR-USER type.
*
* <xmp>
* padata-type ::= PA-FOR-USER
* -- value 129
* padata-value ::= EncryptedData
* -- PA-FOR-USER-ENC
* PA-FOR-USER-ENC ::= SEQUENCE {
* userName[0] PrincipalName,
* userRealm[1] Realm,
* cksum[2] Checksum,
* auth-package[3] KerberosString
* }
* </xmp>
*
* <p>
* This definition reflects MS-SFU.
*/
public class PAForUserEnc {
final public PrincipalName name;
final private EncryptionKey key;
final public static String AUTH_PACKAGE = "Kerberos";
public PAForUserEnc(PrincipalName name, EncryptionKey key) {
this.name = name;
this.key = key;
}
/**
* Constructs a PA-FOR-USER object from a DER encoding.
* @param encoding the input object
* @param key the key to verify the checksum inside encoding
* @throws KrbException if the verification fails.
* Note: this method is now only used by test KDC, therefore
* the verification is ignored (at the moment).
*/
public PAForUserEnc(DerValue encoding, EncryptionKey key)
throws Asn1Exception, KrbException, IOException {
DerValue der = null;
this.key = key;
if (encoding.getTag() != DerValue.tag_Sequence) {
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
// Realm after name? Quite abnormal.
PrincipalName tmpName = null;
der = encoding.getData().getDerValue();
if ((der.getTag() & 0x1F) == 0x00) {
try {
tmpName = new PrincipalName(der.getData().getDerValue(),
new Realm("PLACEHOLDER"));
} catch (RealmException re) {
// Impossible
}
} else {
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
der = encoding.getData().getDerValue();
if ((der.getTag() & 0x1F) == 0x01) {
try {
Realm realm = new Realm(der.getData().getDerValue());
name = new PrincipalName(
tmpName.getNameType(), tmpName.getNameStrings(), realm);
} catch (RealmException re) {
throw new IOException(re);
}
} else {
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
der = encoding.getData().getDerValue();
if ((der.getTag() & 0x1F) == 0x02) {
// Deal with the checksum
} else {
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
der = encoding.getData().getDerValue();
if ((der.getTag() & 0x1F) == 0x03) {
String authPackage = new KerberosString(der.getData().getDerValue()).toString();
if (!authPackage.equalsIgnoreCase(AUTH_PACKAGE)) {
throw new IOException("Incorrect auth-package");
}
} else {
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
if (encoding.getData().available() > 0)
throw new Asn1Exception(Krb5.ASN1_BAD_ID);
}
public byte[] asn1Encode() throws Asn1Exception, IOException {
DerOutputStream bytes = new DerOutputStream();
bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x00), name.asn1Encode());
bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x01), name.getRealm().asn1Encode());
try {
Checksum cks = new Checksum(
Checksum.CKSUMTYPE_HMAC_MD5_ARCFOUR,
getS4UByteArray(),
key,
KeyUsage.KU_PA_FOR_USER_ENC_CKSUM);
bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x02), cks.asn1Encode());
} catch (KrbException ke) {
throw new IOException(ke);
}
DerOutputStream temp = new DerOutputStream();
temp.putDerValue(new KerberosString(AUTH_PACKAGE).toDerValue());
bytes.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0x03), temp);
temp = new DerOutputStream();
temp.write(DerValue.tag_Sequence, bytes);
return temp.toByteArray();
}
/**
* Returns S4UByteArray, the block to calculate checksum inside a
* PA-FOR-USER-ENC data structure. It includes:
* 1. userName.name-type encoded as a 4-byte integer in little endian
* byte order
* 2. all string values in the sequence of strings contained in the
* userName.name-string field
* 3. the string value of the userRealm field
* 4. the string value of auth-package field
*/
public byte[] getS4UByteArray() {
try {
ByteArrayOutputStream ba = new ByteArrayOutputStream();
ba.write(new byte[4]);
for (String s: name.getNameStrings()) {
ba.write(s.getBytes("UTF-8"));
}
ba.write(name.getRealm().toString().getBytes("UTF-8"));
ba.write(AUTH_PACKAGE.getBytes("UTF-8"));
byte[] output = ba.toByteArray();
int pnType = name.getNameType();
output[0] = (byte)(pnType & 0xff);
output[1] = (byte)((pnType>>8) & 0xff);
output[2] = (byte)((pnType>>16) & 0xff);
output[3] = (byte)((pnType>>24) & 0xff);
return output;
} catch (IOException ioe) {
// not possible
throw new AssertionError("Cannot write ByteArrayOutputStream", ioe);
}
}
public String toString() {
return "PA-FOR-USER: " + name;
}
}