1 /*
2 * Copyright (c) 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 jdk.incubator.http;
27
28 import java.net.ProtocolException;
29 import java.nio.ByteBuffer;
30 import java.util.ArrayList;
31 import java.util.HashMap;
32 import java.util.List;
33 import java.util.Locale;
34 import java.util.Map;
35 import static java.lang.String.format;
36 import static java.util.Objects.requireNonNull;
37
38 class Http1HeaderParser {
39
40 private static final char CR = '\r';
41 private static final char LF = '\n';
42 private static final char HT = '\t';
43 private static final char SP = ' ';
44
45 private StringBuilder sb = new StringBuilder();
46 private String statusLine;
47 private int responseCode;
48 private HttpHeaders headers;
49 private Map<String,List<String>> privateMap = new HashMap<>();
50
51 enum State { STATUS_LINE,
52 STATUS_LINE_FOUND_CR,
53 STATUS_LINE_END,
54 STATUS_LINE_END_CR,
55 HEADER,
56 HEADER_FOUND_CR,
57 HEADER_FOUND_LF,
58 HEADER_FOUND_CR_LF,
59 HEADER_FOUND_CR_LF_CR,
60 FINISHED }
61
62 private State state = State.STATUS_LINE;
63
64 /** Returns the status-line. */
65 String statusLine() { return statusLine; }
66
67 /** Returns the response code. */
68 int responseCode() { return responseCode; }
69
70 /** Returns the headers, possibly empty. */
71 HttpHeaders headers() { assert state == State.FINISHED; return headers; }
72
73 /**
74 * Parses HTTP/1.X status-line and headers from the given bytes. Must be
75 * called successive times, with additional data, until returns true.
76 *
77 * All given ByteBuffers will be consumed, until ( possibly ) the last one
78 * ( when true is returned ), which may not be fully consumed.
79 *
80 * @param input the ( partial ) header data
81 * @return true iff the end of the headers block has been reached
82 */
83 boolean parse(ByteBuffer input) throws ProtocolException {
84 requireNonNull(input, "null input");
85
86 while (input.hasRemaining() && state != State.FINISHED) {
87 switch (state) {
88 case STATUS_LINE:
89 readResumeStatusLine(input);
90 break;
91 case STATUS_LINE_FOUND_CR:
92 readStatusLineFeed(input);
93 break;
94 case STATUS_LINE_END:
95 maybeStartHeaders(input);
96 break;
97 case STATUS_LINE_END_CR:
98 maybeEndHeaders(input);
99 break;
100 case HEADER:
101 readResumeHeader(input);
102 break;
103 // fallthrough
104 case HEADER_FOUND_CR:
105 case HEADER_FOUND_LF:
106 resumeOrLF(input);
107 break;
108 case HEADER_FOUND_CR_LF:
109 resumeOrSecondCR(input);
110 break;
111 case HEADER_FOUND_CR_LF_CR:
112 resumeOrEndHeaders(input);
113 break;
114 default:
115 throw new InternalError(
116 "Unexpected state: " + String.valueOf(state));
117 }
118 }
119
120 return state == State.FINISHED;
121 }
122
123 private void readResumeStatusLine(ByteBuffer input) {
124 char c = 0;
125 while (input.hasRemaining() && (c =(char)input.get()) != CR) {
126 sb.append(c);
127 }
128
129 if (c == CR) {
130 state = State.STATUS_LINE_FOUND_CR;
131 }
132 }
133
134 private void readStatusLineFeed(ByteBuffer input) throws ProtocolException {
135 char c = (char)input.get();
136 if (c != LF) {
137 throw protocolException("Bad trailing char, \"%s\", when parsing status-line, \"%s\"",
138 c, sb.toString());
139 }
140
141 statusLine = sb.toString();
142 sb = new StringBuilder();
143 if (!statusLine.startsWith("HTTP/1.")) {
144 throw protocolException("Invalid status line: \"%s\"", statusLine);
145 }
146 if (statusLine.length() < 12) {
147 throw protocolException("Invalid status line: \"%s\"", statusLine);
148 }
149 responseCode = Integer.parseInt(statusLine.substring(9, 12));
150
151 state = State.STATUS_LINE_END;
152 }
153
154 private void maybeStartHeaders(ByteBuffer input) {
155 assert state == State.STATUS_LINE_END;
156 assert sb.length() == 0;
157 char c = (char)input.get();
158 if (c == CR) {
159 state = State.STATUS_LINE_END_CR;
160 } else {
161 sb.append(c);
162 state = State.HEADER;
163 }
164 }
165
166 private void maybeEndHeaders(ByteBuffer input) throws ProtocolException {
167 assert state == State.STATUS_LINE_END_CR;
168 assert sb.length() == 0;
169 char c = (char)input.get();
170 if (c == LF) {
171 headers = ImmutableHeaders.of(privateMap);
172 privateMap = null;
173 state = State.FINISHED; // no headers
174 } else {
175 throw protocolException("Unexpected \"%s\", after status-line CR", c);
176 }
177 }
178
179 private void readResumeHeader(ByteBuffer input) {
180 assert state == State.HEADER;
181 assert input.hasRemaining();
182 while (input.hasRemaining()) {
183 char c = (char)input.get();
184 if (c == CR) {
185 state = State.HEADER_FOUND_CR;
186 break;
187 } else if (c == LF) {
188 state = State.HEADER_FOUND_LF;
189 break;
190 }
191
192 if (c == HT)
193 c = SP;
194 sb.append(c);
195 }
196 }
197
198 private void addHeaderFromString(String headerString) {
199 assert sb.length() == 0;
200 int idx = headerString.indexOf(':');
201 if (idx == -1)
202 return;
203 String name = headerString.substring(0, idx).trim();
204 if (name.isEmpty())
205 return;
206 String value = headerString.substring(idx + 1, headerString.length()).trim();
207
208 privateMap.computeIfAbsent(name.toLowerCase(Locale.US),
209 k -> new ArrayList<>()).add(value);
210 }
211
212 private void resumeOrLF(ByteBuffer input) {
213 assert state == State.HEADER_FOUND_CR || state == State.HEADER_FOUND_LF;
214 char c = (char)input.get();
215 if (c == LF && state == State.HEADER_FOUND_CR) {
216 String headerString = sb.toString();
217 sb = new StringBuilder();
218 addHeaderFromString(headerString);
219 state = State.HEADER_FOUND_CR_LF;
220 } else if (c == SP || c == HT) {
221 sb.append(SP); // parity with MessageHeaders
222 state = State.HEADER;
223 } else {
224 sb = new StringBuilder();
225 sb.append(c);
226 state = State.HEADER;
227 }
228 }
229
230 private void resumeOrSecondCR(ByteBuffer input) {
231 assert state == State.HEADER_FOUND_CR_LF;
232 assert sb.length() == 0;
233 char c = (char)input.get();
234 if (c == CR) {
235 state = State.HEADER_FOUND_CR_LF_CR;
236 } else {
237 sb.append(c);
238 state = State.HEADER;
239 }
240 }
241
242 private void resumeOrEndHeaders(ByteBuffer input) throws ProtocolException {
243 assert state == State.HEADER_FOUND_CR_LF_CR;
244 char c = (char)input.get();
245 if (c == LF) {
246 state = State.FINISHED;
247 headers = ImmutableHeaders.of(privateMap);
248 privateMap = null;
249 } else {
250 throw protocolException("Unexpected \"%s\", after CR LF CR", c);
251 }
252 }
253
254 private ProtocolException protocolException(String format, Object... args) {
255 return new ProtocolException(format(format, args));
256 }
257 }