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1
25
26 package net.killingar.servlet;
27
28 import javax.servlet.http.HttpServlet  ;
29 import javax.servlet.http.HttpServletRequest ;
30 import javax.servlet.http.HttpServletResponse ;
31 import java.io.BufferedOutputStream ;
32 import java.io.IOException ;
33 import java.io.InputStream ;
34 import java.io.OutputStream ;
35 import java.net.InetAddress ;
36 import java.net.MalformedURLException ;
37 import java.net.Socket ;
38 import java.net.URL ;
39
40 public class TunnelServlet extends HttpServlet
41 {
42 private String host;
43 private int port;
44 private String root;
45
46 public TunnelServlet()
47 {
48 }
49
50 public void init()
51 {
52 try
53 {
54 URL url = new URL (getInitParameter("targetRoot"));
55 host = url.getHost();
56 port = url.getPort();
57 if (port == -1)
58 port = 80;
59 root = url.getFile();
60 }
61 catch(MalformedURLException e)
62 {
63 e.printStackTrace();
64 log("TunnelServlet: targetRoot does not specify a valid URL", e);
65 }
66 }
67
68 public void service(HttpServletRequest request, HttpServletResponse response) throws IOException
69 {
70 Socket socket = new Socket (InetAddress.getByName(host), port);
71
72 if (!socket.isBound() || socket.isClosed() || !socket.isConnected() || socket.isOutputShutdown() || socket.isInputShutdown())
73 {
74 throw new RuntimeException ("error connecting to client");
75 }
76
77 OutputStream out = socket.getOutputStream();
78 InputStream in = socket.getInputStream();
79 BufferedOutputStream buf = new BufferedOutputStream (out);
80
81 byte[] buffer = new byte[65536];
82 sendRequest(request, buf, buffer);
83
84 response.reset();
85 sendResponse(in, response, buffer);
86
87 buf.flush();
88 out.flush();
89 out.close();
90 }
91
92 protected void sendRequest(HttpServletRequest request, OutputStream out, byte[] buffer) throws IOException
93 {
94 try
95 {
96 out.write(request.getMethod().getBytes(request.getCharacterEncoding()));
97 out.write(' ');
98 out.write(request.getRequestURI().getBytes(request.getCharacterEncoding()));
99 out.write(" HTTP/1.1\n".getBytes(request.getCharacterEncoding()));
100 out.flush();
101
102 for (java.util.Enumeration e = request.getHeaderNames(); e.hasMoreElements();)
103 {
104 String n = (String )e.nextElement();
105 out.write(n.getBytes(request.getCharacterEncoding()));
106 out.write(':');
107 out.write(request.getHeader(n).getBytes(request.getCharacterEncoding()));
108 out.write('\n');
109 }
110
111 out.write('\n');
112
113 InputStream in = request.getInputStream();
114
115 while (in.available() > 0)
116 {
117 int read = in.read(buffer, 0, 65536);
118 out.write(buffer, 0, read);
119 }
120
121 out.flush();
122 }
123 catch(ArrayIndexOutOfBoundsException e)
124 {
125 }
126 }
127
128 protected void sendResponse(InputStream in, HttpServletResponse response, byte[] buffer) throws IOException
129 {
130 OutputStream out = response.getOutputStream();
131
132 long start = System.currentTimeMillis();
133 while (in.available() <= 0)
134 {
135 try
136 {
137 Thread.sleep(10);
138 }
139 catch (Exception e){}
140
141 if (System.currentTimeMillis()-start > 1000*60) throw new RuntimeException ("timeout");
143 }
144
145
146 boolean parsingHeaders = true;
147 while (in.available() > 0)
148 {
149 int read = in.read(buffer, 0, 65536);
150
151 if (read < 0)
152 break;
153
154 if (parsingHeaders)
155 {
156 for (int i = 0; i < read-4; i++)
157 {
158 if (
159 (buffer[i] == '\n' || buffer[i] == '\r') &&
160 (buffer[i+1] == '\n' || buffer[i+1] == '\r') &&
161 (buffer[i+2] == '\n' || buffer[i+2] == '\r')
162 )
163 {
164 parsingHeaders = false;
165
166 handleHeaders(response, buffer, i+4);
167
168 out.write(buffer, i+4, read-i-4);
169
170 if (read != buffer.length)
171 return;
172 }
173 }
174 }
175 else
176 {
177 out.write(buffer, 0, read);
178 }
179 }
180 }
181
182 protected void handleHeaders(HttpServletResponse response, byte[] buffer, int length)
183 {
184 String [] s = new String (buffer, 0, length).split("[\\n\\r]");
185
186 for (int i = 0; i < s.length; i++)
187 {
188 if (s[i].indexOf(':') != -1)
189 {
190 String [] s2 = s[i].split(":");
191 if (!s2[0].equalsIgnoreCase("Content-Length"))
192 {
193 response.setHeader(s2[0], s2[1]);
194 }
195 }
196 }
197 }
198 }
199 |
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