1 /*
   2  * Copyright 2006-2008 Sun Microsystems, Inc.  All Rights Reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Sun designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Sun in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  22  * CA 95054 USA or visit www.sun.com if you need additional information or
  23  * have any questions.
  24  */
  25 
  26 package sun.security.ssl;
  27 
  28 import java.io.IOException;
  29 import java.io.PrintStream;
  30 import java.util.*;
  31 
  32 import java.security.spec.ECParameterSpec;
  33 
  34 import javax.net.ssl.SSLProtocolException;
  35 
  36 /**
  37  * This file contains all the classes relevant to TLS Extensions for the
  38  * ClientHello and ServerHello messages. The extension mechanism and
  39  * several extensions are defined in RFC 3546. Additional extensions are
  40  * defined in the ECC RFC 4492.
  41  *
  42  * Currently, only the two ECC extensions are fully supported.
  43  *
  44  * The classes contained in this file are:
  45  *  . HelloExtensions: a List of extensions as used in the client hello
  46  *      and server hello messages.
  47  *  . ExtensionType: an enum style class for the extension type
  48  *  . HelloExtension: abstract base class for all extensions. All subclasses
  49  *      must be immutable.
  50  *
  51  *  . UnknownExtension: used to represent all parsed extensions that we do not
  52  *      explicitly support.
  53  *  . ServerNameExtension: partially implemented server_name extension.
  54  *  . SupportedEllipticCurvesExtension: the ECC supported curves extension.
  55  *  . SupportedEllipticPointFormatsExtension: the ECC supported point formats
  56  *      (compressed/uncompressed) extension.
  57  *
  58  * @since   1.6
  59  * @author  Andreas Sterbenz
  60  */
  61 final class HelloExtensions {
  62 
  63     private List<HelloExtension> extensions;
  64     private int encodedLength;
  65 
  66     HelloExtensions() {
  67         extensions = Collections.emptyList();
  68     }
  69 
  70     HelloExtensions(HandshakeInStream s) throws IOException {
  71         int len = s.getInt16();
  72         extensions = new ArrayList<HelloExtension>();
  73         encodedLength = len + 2;
  74         while (len > 0) {
  75             int type = s.getInt16();
  76             int extlen = s.getInt16();
  77             ExtensionType extType = ExtensionType.get(type);
  78             HelloExtension extension;
  79             if (extType == ExtensionType.EXT_SERVER_NAME) {
  80                 extension = new ServerNameExtension(s, extlen);
  81             } else if (extType == ExtensionType.EXT_ELLIPTIC_CURVES) {
  82                 extension = new SupportedEllipticCurvesExtension(s, extlen);
  83             } else if (extType == ExtensionType.EXT_EC_POINT_FORMATS) {
  84                 extension = new SupportedEllipticPointFormatsExtension(s, extlen);
  85             } else {
  86                 extension = new UnknownExtension(s, extlen, extType);
  87             }
  88             extensions.add(extension);
  89             len -= extlen + 4;
  90         }
  91         if (len != 0) {
  92             throw new SSLProtocolException("Error parsing extensions: extra data");
  93         }
  94     }
  95 
  96     // Return the List of extensions. Must not be modified by the caller.
  97     List<HelloExtension> list() {
  98         return extensions;
  99     }
 100 
 101     void add(HelloExtension ext) {
 102         if (extensions.isEmpty()) {
 103             extensions = new ArrayList<HelloExtension>();
 104         }
 105         extensions.add(ext);
 106         encodedLength = -1;
 107     }
 108 
 109     HelloExtension get(ExtensionType type) {
 110         for (HelloExtension ext : extensions) {
 111             if (ext.type == type) {
 112                 return ext;
 113             }
 114         }
 115         return null;
 116     }
 117 
 118     int length() {
 119         if (encodedLength >= 0) {
 120             return encodedLength;
 121         }
 122         if (extensions.isEmpty()) {
 123             encodedLength = 0;
 124         } else {
 125             encodedLength = 2;
 126             for (HelloExtension ext : extensions) {
 127                 encodedLength += ext.length();
 128             }
 129         }
 130         return encodedLength;
 131     }
 132 
 133     void send(HandshakeOutStream s) throws IOException {
 134         int length = length();
 135         if (length == 0) {
 136             return;
 137         }
 138         s.putInt16(length - 2);
 139         for (HelloExtension ext : extensions) {
 140             ext.send(s);
 141         }
 142     }
 143 
 144     void print(PrintStream s) throws IOException {
 145         for (HelloExtension ext : extensions) {
 146             s.println(ext.toString());
 147         }
 148     }
 149 }
 150 
 151 final class ExtensionType {
 152 
 153     final int id;
 154     final String name;
 155 
 156     private ExtensionType(int id, String name) {
 157         this.id = id;
 158         this.name = name;
 159     }
 160 
 161     public String toString() {
 162         return name;
 163     }
 164 
 165     static List<ExtensionType> knownExtensions = new ArrayList<ExtensionType>(8);
 166 
 167     static ExtensionType get(int id) {
 168         for (ExtensionType ext : knownExtensions) {
 169             if (ext.id == id) {
 170                 return ext;
 171             }
 172         }
 173         return new ExtensionType(id, "type_" + id);
 174     }
 175 
 176     private static ExtensionType e(int id, String name) {
 177         ExtensionType ext = new ExtensionType(id, name);
 178         knownExtensions.add(ext);
 179         return ext;
 180     }
 181 
 182     // extensions defined in RFC 3546
 183     final static ExtensionType EXT_SERVER_NAME            = e( 0, "server_name");
 184     final static ExtensionType EXT_MAX_FRAGMENT_LENGTH    = e( 1, "max_fragment_length");
 185     final static ExtensionType EXT_CLIENT_CERTIFICATE_URL = e( 2, "client_certificate_url");
 186     final static ExtensionType EXT_TRUSTED_CA_KEYS        = e( 3, "trusted_ca_keys");
 187     final static ExtensionType EXT_TRUNCATED_HMAC         = e( 4, "truncated_hmac");
 188     final static ExtensionType EXT_STATUS_REQUEST         = e( 5, "status_request");
 189 
 190     // extensions defined in RFC 4492 (ECC)
 191     final static ExtensionType EXT_ELLIPTIC_CURVES        = e(10, "elliptic_curves");
 192     final static ExtensionType EXT_EC_POINT_FORMATS       = e(11, "ec_point_formats");
 193 
 194 }
 195 
 196 abstract class HelloExtension {
 197 
 198     final ExtensionType type;
 199 
 200     HelloExtension(ExtensionType type) {
 201         this.type = type;
 202     }
 203 
 204     // Length of the encoded extension, including the type and length fields
 205     abstract int length();
 206 
 207     abstract void send(HandshakeOutStream s) throws IOException;
 208 
 209     public abstract String toString();
 210 
 211 }
 212 
 213 final class UnknownExtension extends HelloExtension {
 214 
 215     private final byte[] data;
 216 
 217     UnknownExtension(HandshakeInStream s, int len, ExtensionType type)
 218             throws IOException {
 219         super(type);
 220         data = new byte[len];
 221         // s.read() does not handle 0-length arrays.
 222         if (len != 0) {
 223             s.read(data);
 224         }
 225     }
 226 
 227     int length() {
 228         return 4 + data.length;
 229     }
 230 
 231     void send(HandshakeOutStream s) throws IOException {
 232         s.putInt16(type.id);
 233         s.putBytes16(data);
 234     }
 235 
 236     public String toString() {
 237         return "Unsupported extension " + type + ", data: " + Debug.toString(data);
 238     }
 239 }
 240 
 241 // Support for the server_name extension is incomplete. Parsing is implemented
 242 // so that we get nicer debug output, but we neither send it nor do we do
 243 // act on it if we receive it.
 244 final class ServerNameExtension extends HelloExtension {
 245 
 246     final static int NAME_HOST_NAME = 0;
 247 
 248     private List<ServerName> names;
 249 
 250     ServerNameExtension(HandshakeInStream s, int len)
 251             throws IOException {
 252         super(ExtensionType.EXT_SERVER_NAME);
 253         names = new ArrayList<ServerName>();
 254         while (len > 0) {
 255             ServerName name = new ServerName(s);
 256             names.add(name);
 257             len -= name.length + 2;
 258         }
 259         if (len != 0) {
 260             throw new SSLProtocolException("Invalid server_name extension");
 261         }
 262     }
 263 
 264     static class ServerName {
 265         final int length;
 266         final int type;
 267         final byte[] data;
 268         final String hostname;
 269 
 270         ServerName(HandshakeInStream s) throws IOException {
 271             length = s.getInt16();
 272             type = s.getInt8();
 273             data = s.getBytes16();
 274             if (type == NAME_HOST_NAME) {
 275                 hostname = new String(data, "UTF8");
 276             } else {
 277                 hostname = null;
 278             }
 279         }
 280 
 281         public String toString() {
 282             if (type == NAME_HOST_NAME) {
 283                 return "host_name: " + hostname;
 284             } else {
 285                 return "unknown-" + type + ": " + Debug.toString(data);
 286             }
 287         }
 288     }
 289 
 290     int length() {
 291         throw new RuntimeException("not yet supported");
 292     }
 293 
 294     void send(HandshakeOutStream s) throws IOException {
 295         throw new RuntimeException("not yet supported");
 296     }
 297 
 298     public String toString() {
 299         return "Unsupported extension " + type + ", " + names.toString();
 300     }
 301 }
 302 
 303 final class SupportedEllipticCurvesExtension extends HelloExtension {
 304 
 305     // the extension value to send in the ClientHello message
 306     static final SupportedEllipticCurvesExtension DEFAULT;
 307 
 308     private static final boolean fips;
 309 
 310     static {
 311         int[] ids;
 312         fips = SunJSSE.isFIPS();
 313         if (fips == false) {
 314             ids = new int[] {
 315                 // NIST curves first
 316                 // prefer NIST P-256, rest in order of increasing key length
 317                 23, 1, 3, 19, 21, 6, 7, 9, 10, 24, 11, 12, 25, 13, 14,
 318                 // non-NIST curves
 319                 15, 16, 17, 2, 18, 4, 5, 20, 8, 22,
 320             };
 321         } else {
 322             ids = new int[] {
 323                 // same as above, but allow only NIST curves in FIPS mode
 324                 23, 1, 3, 19, 21, 6, 7, 9, 10, 24, 11, 12, 25, 13, 14,
 325             };
 326         }
 327         DEFAULT = new SupportedEllipticCurvesExtension(ids);
 328     }
 329 
 330     private final int[] curveIds;
 331 
 332     private SupportedEllipticCurvesExtension(int[] curveIds) {
 333         super(ExtensionType.EXT_ELLIPTIC_CURVES);
 334         this.curveIds = curveIds;
 335     }
 336 
 337     SupportedEllipticCurvesExtension(HandshakeInStream s, int len)
 338             throws IOException {
 339         super(ExtensionType.EXT_ELLIPTIC_CURVES);
 340         int k = s.getInt16();
 341         if (((len & 1) != 0) || (k + 2 != len)) {
 342             throw new SSLProtocolException("Invalid " + type + " extension");
 343         }
 344         curveIds = new int[k >> 1];
 345         for (int i = 0; i < curveIds.length; i++) {
 346             curveIds[i] = s.getInt16();
 347         }
 348     }
 349 
 350     boolean contains(int index) {
 351         for (int curveId : curveIds) {
 352             if (index == curveId) {
 353                 return true;
 354             }
 355         }
 356         return false;
 357     }
 358 
 359     // Return a reference to the internal curveIds array.
 360     // The caller must NOT modify the contents.
 361     int[] curveIds() {
 362         return curveIds;
 363     }
 364 
 365     int length() {
 366         return 6 + (curveIds.length << 1);
 367     }
 368 
 369     void send(HandshakeOutStream s) throws IOException {
 370         s.putInt16(type.id);
 371         int k = curveIds.length << 1;
 372         s.putInt16(k + 2);
 373         s.putInt16(k);
 374         for (int curveId : curveIds) {
 375             s.putInt16(curveId);
 376         }
 377     }
 378 
 379     public String toString() {
 380         StringBuilder sb = new StringBuilder();
 381         sb.append("Extension " + type + ", curve names: {");
 382         boolean first = true;
 383         for (int curveId : curveIds) {
 384             if (first) {
 385                 first = false;
 386             } else {
 387                 sb.append(", ");
 388             }
 389             // first check if it is a known named curve, then try other cases.
 390             String oid = getCurveOid(curveId);
 391             if (oid != null) {
 392                 ECParameterSpec spec = JsseJce.getECParameterSpec(oid);
 393                 // this toString() output will look nice for the current
 394                 // implementation of the ECParameterSpec class in the Sun
 395                 // provider, but may not look good for other implementations.
 396                 if (spec != null) {
 397                     sb.append(spec.toString().split(" ")[0]);
 398                 } else {
 399                     sb.append(oid);
 400                 }
 401             } else if (curveId == ARBITRARY_PRIME) {
 402                 sb.append("arbitrary_explicit_prime_curves");
 403             } else if (curveId == ARBITRARY_CHAR2) {
 404                 sb.append("arbitrary_explicit_char2_curves");
 405             } else {
 406                 sb.append("unknown curve " + curveId);
 407             }
 408         }
 409         sb.append("}");
 410         return sb.toString();
 411     }
 412 
 413     // Test whether we support the curve with the given index.
 414     static boolean isSupported(int index) {
 415         if ((index <= 0) || (index >= NAMED_CURVE_OID_TABLE.length)) {
 416             return false;
 417         }
 418         if (fips == false) {
 419             // in non-FIPS mode, we support all valid indices
 420             return true;
 421         }
 422         return DEFAULT.contains(index);
 423     }
 424 
 425     static int getCurveIndex(ECParameterSpec params) {
 426         String oid = JsseJce.getNamedCurveOid(params);
 427         if (oid == null) {
 428             return -1;
 429         }
 430         Integer n = curveIndices.get(oid);
 431         return (n == null) ? -1 : n;
 432     }
 433 
 434     static String getCurveOid(int index) {
 435         if ((index > 0) && (index < NAMED_CURVE_OID_TABLE.length)) {
 436             return NAMED_CURVE_OID_TABLE[index];
 437         }
 438         return null;
 439     }
 440 
 441     private final static int ARBITRARY_PRIME = 0xff01;
 442     private final static int ARBITRARY_CHAR2 = 0xff02;
 443 
 444     // See sun.security.ec.NamedCurve for the OIDs
 445     private final static String[] NAMED_CURVE_OID_TABLE = new String[] {
 446         null,                   //  (0) unused
 447         "1.3.132.0.1",          //  (1) sect163k1, NIST K-163
 448         "1.3.132.0.2",          //  (2) sect163r1
 449         "1.3.132.0.15",         //  (3) sect163r2, NIST B-163
 450         "1.3.132.0.24",         //  (4) sect193r1
 451         "1.3.132.0.25",         //  (5) sect193r2
 452         "1.3.132.0.26",         //  (6) sect233k1, NIST K-233
 453         "1.3.132.0.27",         //  (7) sect233r1, NIST B-233
 454         "1.3.132.0.3",          //  (8) sect239k1
 455         "1.3.132.0.16",         //  (9) sect283k1, NIST K-283
 456         "1.3.132.0.17",         // (10) sect283r1, NIST B-283
 457         "1.3.132.0.36",         // (11) sect409k1, NIST K-409
 458         "1.3.132.0.37",         // (12) sect409r1, NIST B-409
 459         "1.3.132.0.38",         // (13) sect571k1, NIST K-571
 460         "1.3.132.0.39",         // (14) sect571r1, NIST B-571
 461         "1.3.132.0.9",          // (15) secp160k1
 462         "1.3.132.0.8",          // (16) secp160r1
 463         "1.3.132.0.30",         // (17) secp160r2
 464         "1.3.132.0.31",         // (18) secp192k1
 465         "1.2.840.10045.3.1.1",  // (19) secp192r1, NIST P-192
 466         "1.3.132.0.32",         // (20) secp224k1
 467         "1.3.132.0.33",         // (21) secp224r1, NIST P-224
 468         "1.3.132.0.10",         // (22) secp256k1
 469         "1.2.840.10045.3.1.7",  // (23) secp256r1, NIST P-256
 470         "1.3.132.0.34",         // (24) secp384r1, NIST P-384
 471         "1.3.132.0.35",         // (25) secp521r1, NIST P-521
 472     };
 473 
 474     private final static Map<String,Integer> curveIndices;
 475 
 476     static {
 477         curveIndices = new HashMap<String,Integer>();
 478         for (int i = 1; i < NAMED_CURVE_OID_TABLE.length; i++) {
 479             curveIndices.put(NAMED_CURVE_OID_TABLE[i], i);
 480         }
 481     }
 482 
 483 }
 484 
 485 final class SupportedEllipticPointFormatsExtension extends HelloExtension {
 486 
 487     final static int FMT_UNCOMPRESSED = 0;
 488     final static int FMT_ANSIX962_COMPRESSED_PRIME = 1;
 489     final static int FMT_ANSIX962_COMPRESSED_CHAR2 = 2;
 490 
 491     static final HelloExtension DEFAULT =
 492         new SupportedEllipticPointFormatsExtension(new byte[] {FMT_UNCOMPRESSED});
 493 
 494     private final byte[] formats;
 495 
 496     private SupportedEllipticPointFormatsExtension(byte[] formats) {
 497         super(ExtensionType.EXT_EC_POINT_FORMATS);
 498         this.formats = formats;
 499     }
 500 
 501     SupportedEllipticPointFormatsExtension(HandshakeInStream s, int len)
 502             throws IOException {
 503         super(ExtensionType.EXT_EC_POINT_FORMATS);
 504         formats = s.getBytes8();
 505         // RFC 4492 says uncompressed points must always be supported.
 506         // Check just to make sure.
 507         boolean uncompressed = false;
 508         for (int format : formats) {
 509             if (format == FMT_UNCOMPRESSED) {
 510                 uncompressed = true;
 511                 break;
 512             }
 513         }
 514         if (uncompressed == false) {
 515             throw new SSLProtocolException
 516                 ("Peer does not support uncompressed points");
 517         }
 518     }
 519 
 520     int length() {
 521         return 5 + formats.length;
 522     }
 523 
 524     void send(HandshakeOutStream s) throws IOException {
 525         s.putInt16(type.id);
 526         s.putInt16(formats.length + 1);
 527         s.putBytes8(formats);
 528     }
 529 
 530     private static String toString(byte format) {
 531         int f = format & 0xff;
 532         switch (f) {
 533         case FMT_UNCOMPRESSED:
 534             return "uncompressed";
 535         case FMT_ANSIX962_COMPRESSED_PRIME:
 536             return "ansiX962_compressed_prime";
 537         case FMT_ANSIX962_COMPRESSED_CHAR2:
 538             return "ansiX962_compressed_char2";
 539         default:
 540             return "unknown-" + f;
 541         }
 542     }
 543 
 544     public String toString() {
 545         List<String> list = new ArrayList<String>();
 546         for (byte format : formats) {
 547             list.add(toString(format));
 548         }
 549         return "Extension " + type + ", formats: " + list;
 550     }
 551 }