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* 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
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* 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,
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package sun.security.rsa;
import java.io.*;
import sun.security.util.*;
import sun.security.x509.*;
import java.security.AlgorithmParametersSpi;
import java.security.NoSuchAlgorithmException;
import java.security.spec.AlgorithmParameterSpec;
import java.security.spec.InvalidParameterSpecException;
import java.security.spec.MGF1ParameterSpec;
import java.security.spec.PSSParameterSpec;
import static java.security.spec.PSSParameterSpec.DEFAULT;
/**
* This class implements the PSS parameters used with the RSA
* signatures in PSS padding. Here is its ASN.1 definition:
* RSASSA-PSS-params ::= SEQUENCE {
* hashAlgorithm [0] HashAlgorithm DEFAULT sha1,
* maskGenAlgorithm [1] MaskGenAlgorithm DEFAULT mgf1SHA1,
* saltLength [2] INTEGER DEFAULT 20
* trailerField [3] TrailerField DEFAULT trailerFieldBC
* }
*
* @author Valerie Peng
*
*/
public final class PSSParameters extends AlgorithmParametersSpi {
private String mdName;
private MGF1ParameterSpec mgfSpec;
private int saltLength;
private int trailerField;
private static final ObjectIdentifier OID_MGF1 =
ObjectIdentifier.newInternal(new int[] {1,2,840,113549,1,1,8});
public PSSParameters() {
}
@Override
protected void engineInit(AlgorithmParameterSpec paramSpec)
throws InvalidParameterSpecException {
if (!(paramSpec instanceof PSSParameterSpec)) {
throw new InvalidParameterSpecException
("Inappropriate parameter specification");
}
PSSParameterSpec spec = (PSSParameterSpec) paramSpec;
this.mdName = spec.getDigestAlgorithm();
String mgfName = spec.getMGFAlgorithm();
if (!mgfName.equalsIgnoreCase("MGF1")) {
throw new InvalidParameterSpecException("Unsupported mgf " +
mgfName + "; MGF1 only");
}
AlgorithmParameterSpec mgfSpec = spec.getMGFParameters();
if (!(mgfSpec instanceof MGF1ParameterSpec)) {
throw new InvalidParameterSpecException("Inappropriate mgf " +
"parameters; non-null MGF1ParameterSpec only");
}
this.mgfSpec = (MGF1ParameterSpec) mgfSpec;
this.saltLength = spec.getSaltLength();
this.trailerField = spec.getTrailerField();
}
@Override
protected void engineInit(byte[] encoded) throws IOException {
// first initialize with the DEFAULT values before
// retrieving from the encoding bytes
this.mdName = DEFAULT.getDigestAlgorithm();
this.mgfSpec = (MGF1ParameterSpec) DEFAULT.getMGFParameters();
this.saltLength = DEFAULT.getSaltLength();
this.trailerField = DEFAULT.getTrailerField();
DerInputStream der = new DerInputStream(encoded);
DerValue[] datum = der.getSequence(4);
for (DerValue d : datum) {
if (d.isContextSpecific((byte) 0x00)) {
// hash algid
this.mdName = AlgorithmId.parse
(d.data.getDerValue()).getName();
} else if (d.isContextSpecific((byte) 0x01)) {
// mgf algid
AlgorithmId val = AlgorithmId.parse(d.data.getDerValue());
if (!val.getOID().equals(OID_MGF1)) {
throw new IOException("Only MGF1 mgf is supported");
}
AlgorithmId params = AlgorithmId.parse(
new DerValue(val.getEncodedParams()));
String mgfDigestName = params.getName();
switch (mgfDigestName) {
case "SHA-1":
this.mgfSpec = MGF1ParameterSpec.SHA1;
break;
case "SHA-224":
this.mgfSpec = MGF1ParameterSpec.SHA224;
break;
case "SHA-256":
this.mgfSpec = MGF1ParameterSpec.SHA256;
break;
case "SHA-384":
this.mgfSpec = MGF1ParameterSpec.SHA384;
break;
case "SHA-512":
this.mgfSpec = MGF1ParameterSpec.SHA512;
break;
case "SHA-512/224":
this.mgfSpec = MGF1ParameterSpec.SHA512_224;
break;
case "SHA-512/256":
this.mgfSpec = MGF1ParameterSpec.SHA512_256;
break;
default:
throw new IOException
("Unrecognized message digest algorithm " +
mgfDigestName);
}
} else if (d.isContextSpecific((byte) 0x02)) {
// salt length
this.saltLength = d.data.getDerValue().getInteger();
if (this.saltLength < 0) {
throw new IOException("Negative value for saltLength");
}
} else if (d.isContextSpecific((byte) 0x03)) {
// trailer field
this.trailerField = d.data.getDerValue().getInteger();
if (this.trailerField != 1) {
throw new IOException("Unsupported trailerField value " +
this.trailerField);
}
} else {
throw new IOException("Invalid encoded PSSParameters");
}
}
}
@Override
protected void engineInit(byte[] encoded, String decodingMethod)
throws IOException {
if ((decodingMethod != null) &&
(!decodingMethod.equalsIgnoreCase("ASN.1"))) {
throw new IllegalArgumentException("Only support ASN.1 format");
}
engineInit(encoded);
}
@Override
protected <T extends AlgorithmParameterSpec>
T engineGetParameterSpec(Class<T> paramSpec)
throws InvalidParameterSpecException {
if (PSSParameterSpec.class.isAssignableFrom(paramSpec)) {
return paramSpec.cast(
new PSSParameterSpec(mdName, "MGF1", mgfSpec,
saltLength, trailerField));
} else {
throw new InvalidParameterSpecException
("Inappropriate parameter specification");
}
}
@Override
protected byte[] engineGetEncoded() throws IOException {
DerOutputStream tmp = new DerOutputStream();
DerOutputStream tmp2, tmp3;
// MD
AlgorithmId mdAlgId;
try {
mdAlgId = AlgorithmId.get(mdName);
} catch (NoSuchAlgorithmException nsae) {
throw new IOException("AlgorithmId " + mdName +
" impl not found");
}
tmp2 = new DerOutputStream();
mdAlgId.derEncode(tmp2);
tmp.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)0),
tmp2);
// MGF
tmp2 = new DerOutputStream();
tmp2.putOID(OID_MGF1);
AlgorithmId mgfDigestId;
try {
mgfDigestId = AlgorithmId.get(mgfSpec.getDigestAlgorithm());
} catch (NoSuchAlgorithmException nase) {
throw new IOException("AlgorithmId " +
mgfSpec.getDigestAlgorithm() + " impl not found");
}
mgfDigestId.encode(tmp2);
tmp3 = new DerOutputStream();
tmp3.write(DerValue.tag_Sequence, tmp2);
tmp.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)1),
tmp3);
// SaltLength
tmp2 = new DerOutputStream();
tmp2.putInteger(saltLength);
tmp.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)2),
tmp2);
// TrailerField
tmp2 = new DerOutputStream();
tmp2.putInteger(trailerField);
tmp.write(DerValue.createTag(DerValue.TAG_CONTEXT, true, (byte)3),
tmp2);
// Put all together under a SEQUENCE tag
DerOutputStream out = new DerOutputStream();
out.write(DerValue.tag_Sequence, tmp);
return out.toByteArray();
}
@Override
protected byte[] engineGetEncoded(String encMethod) throws IOException {
if ((encMethod != null) &&
(!encMethod.equalsIgnoreCase("ASN.1"))) {
throw new IllegalArgumentException("Only support ASN.1 format");
}
return engineGetEncoded();
}
@Override
protected String engineToString() {
StringBuilder sb = new StringBuilder();
sb.append("MD: " + mdName + "\n")
.append("MGF: MGF1" + mgfSpec.getDigestAlgorithm() + "\n")
.append("SaltLength: " + saltLength + "\n")
.append("TrailerField: " + trailerField + "\n");
return sb.toString();
}
}