1 /*
2 * Copyright (c) 2006, 2017, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.security.ssl;
27
28 import java.io.IOException;
29 import java.io.PrintStream;
30 import java.util.*;
31 import javax.net.ssl.*;
32
33 /**
34 * This file contains all the classes relevant to TLS Extensions for the
35 * ClientHello and ServerHello messages. The extension mechanism and
36 * several extensions are defined in RFC 6066. Additional extensions are
37 * defined in the ECC RFC 4492 and the ALPN extension is defined in RFC 7301.
38 *
39 * Currently, only the two ECC extensions are fully supported.
40 *
41 * The classes contained in this file are:
42 * . HelloExtensions: a List of extensions as used in the client hello
43 * and server hello messages.
44 * . ExtensionType: an enum style class for the extension type
45 * . HelloExtension: abstract base class for all extensions. All subclasses
46 * must be immutable.
47 *
48 * . UnknownExtension: used to represent all parsed extensions that we do not
49 * explicitly support.
50 * . ServerNameExtension: the server_name extension.
51 * . SignatureAlgorithmsExtension: the signature_algorithms extension.
52 * . SupportedGroupsExtension: the supported groups extension.
53 * . EllipticPointFormatsExtension: the ECC supported point formats
54 * (compressed/uncompressed) extension.
55 * . ALPNExtension: the application_layer_protocol_negotiation extension.
56 *
57 * @since 1.6
58 * @author Andreas Sterbenz
59 */
60 final class HelloExtensions {
61
62 private List<HelloExtension> extensions;
63 private int encodedLength;
64
65 HelloExtensions() {
66 extensions = Collections.emptyList();
67 }
68
69 HelloExtensions(HandshakeInStream s) throws IOException {
70 int len = s.getInt16();
71 extensions = new ArrayList<HelloExtension>();
72 encodedLength = len + 2;
73 while (len > 0) {
74 int type = s.getInt16();
75 int extlen = s.getInt16();
76 ExtensionType extType = ExtensionType.get(type);
77 HelloExtension extension;
78 if (extType == ExtensionType.EXT_SERVER_NAME) {
79 extension = new ServerNameExtension(s, extlen);
80 } else if (extType == ExtensionType.EXT_SIGNATURE_ALGORITHMS) {
81 extension = new SignatureAlgorithmsExtension(s, extlen);
82 } else if (extType == ExtensionType.EXT_SUPPORTED_GROUPS) {
83 extension = new SupportedGroupsExtension(s, extlen);
84 } else if (extType == ExtensionType.EXT_EC_POINT_FORMATS) {
85 extension = new EllipticPointFormatsExtension(s, extlen);
86 } else if (extType == ExtensionType.EXT_RENEGOTIATION_INFO) {
87 extension = new RenegotiationInfoExtension(s, extlen);
88 } else if (extType == ExtensionType.EXT_ALPN) {
89 extension = new ALPNExtension(s, extlen);
90 } else if (extType == ExtensionType.EXT_MAX_FRAGMENT_LENGTH) {
91 extension = new MaxFragmentLengthExtension(s, extlen);
92 } else if (extType == ExtensionType.EXT_STATUS_REQUEST) {
93 extension = new CertStatusReqExtension(s, extlen);
94 } else if (extType == ExtensionType.EXT_STATUS_REQUEST_V2) {
95 extension = new CertStatusReqListV2Extension(s, extlen);
96 } else if (extType == ExtensionType.EXT_EXTENDED_MASTER_SECRET) {
97 extension = new ExtendedMasterSecretExtension(s, extlen);
98 } else {
99 extension = new UnknownExtension(s, extlen, extType);
100 }
101 extensions.add(extension);
102 len -= extlen + 4;
103 }
104 if (len != 0) {
105 throw new SSLProtocolException(
106 "Error parsing extensions: extra data");
107 }
108 }
109
110 // Return the List of extensions. Must not be modified by the caller.
111 List<HelloExtension> list() {
112 return extensions;
113 }
114
115 void add(HelloExtension ext) {
116 if (extensions.isEmpty()) {
117 extensions = new ArrayList<HelloExtension>();
118 }
119 extensions.add(ext);
120 encodedLength = -1;
121 }
122
123 HelloExtension get(ExtensionType type) {
124 for (HelloExtension ext : extensions) {
125 if (ext.type == type) {
126 return ext;
127 }
128 }
129 return null;
130 }
131
132 int length() {
133 if (encodedLength >= 0) {
134 return encodedLength;
135 }
136 if (extensions.isEmpty()) {
137 encodedLength = 0;
138 } else {
139 encodedLength = 2;
140 for (HelloExtension ext : extensions) {
141 encodedLength += ext.length();
142 }
143 }
144 return encodedLength;
145 }
146
147 void send(HandshakeOutStream s) throws IOException {
148 int length = length();
149 if (length == 0) {
150 return;
151 }
152 s.putInt16(length - 2);
153 for (HelloExtension ext : extensions) {
154 ext.send(s);
155 }
156 }
157
158 void print(PrintStream s) throws IOException {
159 for (HelloExtension ext : extensions) {
160 s.println(ext.toString());
161 }
162 }
163 }