/*
* Copyright (c) 2006, 2016, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* 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
* by Oracle in the LICENSE file that accompanied this code.
*
* 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).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.security.ssl;
import java.io.IOException;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECGenParameterSpec;
import java.security.spec.InvalidParameterSpecException;
import java.security.AlgorithmParameters;
import java.security.AlgorithmConstraints;
import java.security.CryptoPrimitive;
import java.security.AccessController;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.Map;
import java.util.ArrayList;
import javax.net.ssl.SSLProtocolException;
import sun.security.action.GetPropertyAction;
final class EllipticCurvesExtension extends HelloExtension {
private static final int ARBITRARY_PRIME = 0xff01;
private static final int ARBITRARY_CHAR2 = 0xff02;
// speed up the searching
private static final Map<String, Integer> oidToIdMap = new HashMap<>();
private static final Map<Integer, String> idToOidMap = new HashMap<>();
// speed up the parameters construction
private static final Map<Integer,
AlgorithmParameters> idToParams = new HashMap<>();
// the supported elliptic curves
private static final int[] supportedCurveIds;
// the curves of the extension
private final int[] curveIds;
// See sun.security.util.CurveDB for the OIDs
private static enum NamedEllipticCurve {
T163_K1(1, "sect163k1", "1.3.132.0.1", true), // NIST K-163
T163_R1(2, "sect163r1", "1.3.132.0.2", false),
T163_R2(3, "sect163r2", "1.3.132.0.15", true), // NIST B-163
T193_R1(4, "sect193r1", "1.3.132.0.24", false),
T193_R2(5, "sect193r2", "1.3.132.0.25", false),
T233_K1(6, "sect233k1", "1.3.132.0.26", true), // NIST K-233
T233_R1(7, "sect233r1", "1.3.132.0.27", true), // NIST B-233
T239_K1(8, "sect239k1", "1.3.132.0.3", false),
T283_K1(9, "sect283k1", "1.3.132.0.16", true), // NIST K-283
T283_R1(10, "sect283r1", "1.3.132.0.17", true), // NIST B-283
T409_K1(11, "sect409k1", "1.3.132.0.36", true), // NIST K-409
T409_R1(12, "sect409r1", "1.3.132.0.37", true), // NIST B-409
T571_K1(13, "sect571k1", "1.3.132.0.38", true), // NIST K-571
T571_R1(14, "sect571r1", "1.3.132.0.39", true), // NIST B-571
P160_K1(15, "secp160k1", "1.3.132.0.9", false),
P160_R1(16, "secp160r1", "1.3.132.0.8", false),
P160_R2(17, "secp160r2", "1.3.132.0.30", false),
P192_K1(18, "secp192k1", "1.3.132.0.31", false),
P192_R1(19, "secp192r1", "1.2.840.10045.3.1.1", true), // NIST P-192
P224_K1(20, "secp224k1", "1.3.132.0.32", false),
P224_R1(21, "secp224r1", "1.3.132.0.33", true), // NIST P-224
P256_K1(22, "secp256k1", "1.3.132.0.10", false),
P256_R1(23, "secp256r1", "1.2.840.10045.3.1.7", true), // NIST P-256
P384_R1(24, "secp384r1", "1.3.132.0.34", true), // NIST P-384
P521_R1(25, "secp521r1", "1.3.132.0.35", true); // NIST P-521
int id;
String name;
String oid;
boolean isFips;
NamedEllipticCurve(int id, String name, String oid, boolean isFips) {
this.id = id;
this.name = name;
this.oid = oid;
this.isFips = isFips;
if (oidToIdMap.put(oid, id) != null ||
idToOidMap.put(id, oid) != null) {
throw new RuntimeException(
"Duplicate named elliptic curve definition: " + name);
}
}
static NamedEllipticCurve getCurve(String name, boolean requireFips) {
for (NamedEllipticCurve curve : NamedEllipticCurve.values()) {
if (curve.name.equals(name) && (!requireFips || curve.isFips)) {
return curve;
}
}
return null;
}
}
static {
boolean requireFips = SunJSSE.isFIPS();
// hack code to initialize NamedEllipticCurve
NamedEllipticCurve nec =
NamedEllipticCurve.getCurve("secp256r1", false);
// The value of the System Property defines a list of enabled named
// curves in preference order, separated with comma. For example:
//
// jdk.tls.namedGroups="secp521r1, secp256r1, secp384r1"
//
// If the System Property is not defined or the value is empty, the
// default curves and preferences will be used.
String property = AccessController.doPrivileged(
new GetPropertyAction("jdk.tls.namedGroups"));
if (property != null && property.length() != 0) {
// remove double quote marks from beginning/end of the property
if (property.length() > 1 && property.charAt(0) == '"' &&
property.charAt(property.length() - 1) == '"') {
property = property.substring(1, property.length() - 1);
}
}
ArrayList<Integer> idList;
if (property != null && property.length() != 0) { // customized curves
String[] curves = property.split(",");
idList = new ArrayList<>(curves.length);
for (String curve : curves) {
curve = curve.trim();
if (!curve.isEmpty()) {
NamedEllipticCurve namedCurve =
NamedEllipticCurve.getCurve(curve, requireFips);
if (namedCurve != null) {
if (isAvailableCurve(namedCurve.id)) {
idList.add(namedCurve.id);
}
} // ignore unknown curves
}
}
} else { // default curves
int[] ids;
if (requireFips) {
ids = new int[] {
// only NIST curves in FIPS mode
23, 24, 25, 9, 10, 11, 12, 13, 14,
};
} else {
ids = new int[] {
// NIST curves first
23, 24, 25, 9, 10, 11, 12, 13, 14,
// non-NIST curves
22,
};
}
idList = new ArrayList<>(ids.length);
for (int curveId : ids) {
if (isAvailableCurve(curveId)) {
idList.add(curveId);
}
}
}
if (idList.isEmpty()) {
throw new IllegalArgumentException(
"System property jdk.tls.namedGroups(" + property + ") " +
"contains no supported elliptic curves");
} else {
supportedCurveIds = new int[idList.size()];
int i = 0;
for (Integer id : idList) {
supportedCurveIds[i++] = id;
}
}
}
// check whether the curve is supported by the underlying providers
private static boolean isAvailableCurve(int curveId) {
String oid = idToOidMap.get(curveId);
if (oid != null) {
AlgorithmParameters params = null;
try {
params = JsseJce.getAlgorithmParameters("EC");
params.init(new ECGenParameterSpec(oid));
} catch (Exception e) {
return false;
}
// cache the parameters
idToParams.put(curveId, params);
return true;
}
return false;
}
private EllipticCurvesExtension(int[] curveIds) {
super(ExtensionType.EXT_ELLIPTIC_CURVES);
this.curveIds = curveIds;
}
EllipticCurvesExtension(HandshakeInStream s, int len)
throws IOException {
super(ExtensionType.EXT_ELLIPTIC_CURVES);
int k = s.getInt16();
if (((len & 1) != 0) || (k + 2 != len)) {
throw new SSLProtocolException("Invalid " + type + " extension");
}
// Note: unknown curves will be ignored later.
curveIds = new int[k >> 1];
for (int i = 0; i < curveIds.length; i++) {
curveIds[i] = s.getInt16();
}
}
// get the preferred active curve
static int getActiveCurves(AlgorithmConstraints constraints) {
return getPreferredCurve(supportedCurveIds, constraints);
}
static boolean hasActiveCurves(AlgorithmConstraints constraints) {
return getActiveCurves(constraints) >= 0;
}
static EllipticCurvesExtension createExtension(
AlgorithmConstraints constraints) {
ArrayList<Integer> idList = new ArrayList<>(supportedCurveIds.length);
for (int curveId : supportedCurveIds) {
if (constraints.permits(
EnumSet.of(CryptoPrimitive.KEY_AGREEMENT),
"EC", idToParams.get(curveId))) {
idList.add(curveId);
}
}
if (!idList.isEmpty()) {
int[] ids = new int[idList.size()];
int i = 0;
for (Integer id : idList) {
ids[i++] = id;
}
return new EllipticCurvesExtension(ids);
}
return null;
}
// get the preferred activated curve
int getPreferredCurve(AlgorithmConstraints constraints) {
return getPreferredCurve(curveIds, constraints);
}
// get a preferred activated curve
private static int getPreferredCurve(int[] curves,
AlgorithmConstraints constraints) {
for (int curveId : curves) {
if (isSupported(curveId) && constraints.permits(
EnumSet.of(CryptoPrimitive.KEY_AGREEMENT),
"EC", idToParams.get(curveId))) {
return curveId;
}
}
return -1;
}
boolean contains(int index) {
for (int curveId : curveIds) {
if (index == curveId) {
return true;
}
}
return false;
}
@Override
int length() {
return 6 + (curveIds.length << 1);
}
@Override
void send(HandshakeOutStream s) throws IOException {
s.putInt16(type.id);
int k = curveIds.length << 1;
s.putInt16(k + 2);
s.putInt16(k);
for (int curveId : curveIds) {
s.putInt16(curveId);
}
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("Extension " + type + ", curve names: {");
boolean first = true;
for (int curveId : curveIds) {
if (first) {
first = false;
} else {
sb.append(", ");
}
// first check if it is a known named curve, then try other cases.
String curveName = getCurveName(curveId);
if (curveName != null) {
sb.append(curveName);
} else if (curveId == ARBITRARY_PRIME) {
sb.append("arbitrary_explicit_prime_curves");
} else if (curveId == ARBITRARY_CHAR2) {
sb.append("arbitrary_explicit_char2_curves");
} else {
sb.append("unknown curve " + curveId);
}
}
sb.append("}");
return sb.toString();
}
// Test whether the given curve is supported.
static boolean isSupported(int index) {
for (int curveId : supportedCurveIds) {
if (index == curveId) {
return true;
}
}
return false;
}
static int getCurveIndex(ECParameterSpec params) {
String oid = JsseJce.getNamedCurveOid(params);
if (oid == null) {
return -1;
}
Integer n = oidToIdMap.get(oid);
return (n == null) ? -1 : n;
}
static String getCurveOid(int index) {
return idToOidMap.get(index);
}
static ECGenParameterSpec getECGenParamSpec(int index) {
AlgorithmParameters params = idToParams.get(index);
try {
return params.getParameterSpec(ECGenParameterSpec.class);
} catch (InvalidParameterSpecException ipse) {
// should be unlikely
String curveOid = getCurveOid(index);
return new ECGenParameterSpec(curveOid);
}
}
private static String getCurveName(int index) {
for (NamedEllipticCurve namedCurve : NamedEllipticCurve.values()) {
if (namedCurve.id == index) {
return namedCurve.name;
}
}
return null;
}
}