forked from PurpleI2P/i2pd
-
Notifications
You must be signed in to change notification settings - Fork 0
/
HTTPProxy.cpp
336 lines (301 loc) · 11 KB
/
HTTPProxy.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
#include <cstring>
#include <cassert>
#include <string>
#include <atomic>
#include <memory>
#include <set>
#include <boost/asio.hpp>
#include <mutex>
#include "I2PService.h"
#include "Destination.h"
#include "HTTPProxy.h"
#include "util.h"
#include "Identity.h"
#include "Streaming.h"
#include "Destination.h"
#include "ClientContext.h"
#include "I2PEndian.h"
#include "I2PTunnel.h"
#include "Config.h"
#include "HTTP.h"
namespace i2p {
namespace proxy {
std::map<std::string, std::string> jumpservices = {
{ "inr.i2p", "http://joajgazyztfssty4w2on5oaqksz6tqoxbduy553y34mf4byv6gpq.b32.i2p/search/?q=" },
{ "stats.i2p", "http://7tbay5p4kzeekxvyvbf6v7eauazemsnnl2aoyqhg5jzpr5eke7tq.b32.i2p/cgi-bin/jump.cgi?a=" },
};
static const char *pageHead =
"<head>\r\n"
" <title>I2P HTTP proxy: error</title>\r\n"
" <style type=\"text/css\">\r\n"
" body { font: 100%/1.5em sans-serif; margin: 0; padding: 1.5em; background: #FAFAFA; color: #103456; }\r\n"
" .header { font-size: 2.5em; text-align: center; margin: 1.5em 0; color: #894C84; }\r\n"
" </style>\r\n"
"</head>\r\n"
;
bool str_rmatch(std::string & str, const char *suffix) {
auto pos = str.rfind (suffix);
if (pos == std::string::npos)
return false; /* not found */
if (str.length() == (pos + std::strlen(suffix)))
return true; /* match */
return false;
}
class HTTPReqHandler: public i2p::client::I2PServiceHandler, public std::enable_shared_from_this<HTTPReqHandler>
{
private:
bool HandleRequest();
void HandleSockRecv(const boost::system::error_code & ecode, std::size_t bytes_transfered);
void Terminate();
void AsyncSockRead();
bool ExtractAddressHelper(i2p::http::URL & url, std::string & b64);
void SanitizeHTTPRequest(i2p::http::HTTPReq & req);
void SentHTTPFailed(const boost::system::error_code & ecode);
void HandleStreamRequestComplete (std::shared_ptr<i2p::stream::Stream> stream);
/* error helpers */
void GenericProxyError(const char *title, const char *description);
void HostNotFound(std::string & host);
void SendProxyError(std::string & content);
uint8_t m_recv_chunk[8192];
std::string m_recv_buf; // from client
std::string m_send_buf; // to upstream
std::shared_ptr<boost::asio::ip::tcp::socket> m_sock;
public:
HTTPReqHandler(HTTPProxy * parent, std::shared_ptr<boost::asio::ip::tcp::socket> sock) :
I2PServiceHandler(parent), m_sock(sock) {}
~HTTPReqHandler() { Terminate(); }
void Handle () { AsyncSockRead(); } /* overload */
};
void HTTPReqHandler::AsyncSockRead()
{
LogPrint(eLogDebug, "HTTPProxy: async sock read");
if (!m_sock) {
LogPrint(eLogError, "HTTPProxy: no socket for read");
return;
}
m_sock->async_read_some(boost::asio::buffer(m_recv_chunk, sizeof(m_recv_chunk)),
std::bind(&HTTPReqHandler::HandleSockRecv, shared_from_this(),
std::placeholders::_1, std::placeholders::_2));
}
void HTTPReqHandler::Terminate() {
if (Kill()) return;
if (m_sock)
{
LogPrint(eLogDebug, "HTTPProxy: close sock");
m_sock->close();
m_sock = nullptr;
}
Done(shared_from_this());
}
void HTTPReqHandler::GenericProxyError(const char *title, const char *description) {
std::stringstream ss;
ss << "<h1>Proxy error: " << title << "</h1>\r\n";
ss << "<p>" << description << "</p>\r\n";
std::string content = ss.str();
SendProxyError(content);
}
void HTTPReqHandler::HostNotFound(std::string & host) {
std::stringstream ss;
ss << "<h1>Proxy error: Host not found</h1>\r\n"
<< "<p>Remote host not found in router's addressbook</p>\r\n"
<< "<p>You may try to find this host on jumpservices below:</p>\r\n"
<< "<ul>\r\n";
for (auto & js : jumpservices) {
ss << " <li><a href=\"" << js.second << host << "\">" << js.first << "</a></li>\r\n";
}
ss << "</ul>\r\n";
std::string content = ss.str();
SendProxyError(content);
}
void HTTPReqHandler::SendProxyError(std::string & content)
{
i2p::http::HTTPRes res;
res.code = 500;
res.add_header("Content-Type", "text/html; charset=UTF-8");
res.add_header("Connection", "close");
std::stringstream ss;
ss << "<html>\r\n" << pageHead
<< "<body>" << content << "</body>\r\n"
<< "</html>\r\n";
res.body = ss.str();
std::string response = res.to_string();
boost::asio::async_write(*m_sock, boost::asio::buffer(response),
std::bind(&HTTPReqHandler::SentHTTPFailed, shared_from_this(), std::placeholders::_1));
}
bool HTTPReqHandler::ExtractAddressHelper(i2p::http::URL & url, std::string & b64)
{
const char *param = "i2paddresshelper=";
std::size_t pos = url.query.find(param);
std::size_t len = std::strlen(param);
std::map<std::string, std::string> params;
if (pos == std::string::npos)
return false; /* not found */
if (!url.parse_query(params))
return false;
std::string value = params["i2paddresshelper"];
len += value.length();
b64 = i2p::http::UrlDecode(value);
url.query.replace(pos, len, "");
return true;
}
void HTTPReqHandler::SanitizeHTTPRequest(i2p::http::HTTPReq & req)
{
/* drop common headers */
req.del_header("Referer");
req.del_header("Via");
req.del_header("Forwarded");
/* drop proxy-disclosing headers */
std::vector<std::string> toErase;
for (auto it : req.headers) {
if (it.first.compare(0, 12, "X-Forwarded-") == 0) {
toErase.push_back(it.first);
} else if (it.first.compare(0, 6, "Proxy-") == 0) {
toErase.push_back(it.first);
} else {
/* allow */
}
}
for (auto header : toErase) {
req.headers.erase(header);
}
/* replace headers */
req.add_header("Connection", "close", true); /* keep-alive conns not supported yet */
req.add_header("User-Agent", "MYOB/6.66 (AN/ON)", true); /* privacy */
}
/**
* @brief Try to parse request from @a m_recv_buf
* If parsing success, rebuild request and store to @a m_send_buf
* with remaining data tail
* @return true on processed request or false if more data needed
*/
bool HTTPReqHandler::HandleRequest()
{
i2p::http::HTTPReq req;
i2p::http::URL url;
std::string b64;
int req_len = 0;
req_len = req.parse(m_recv_buf);
if (req_len == 0)
return false; /* need more data */
if (req_len < 0) {
LogPrint(eLogError, "HTTPProxy: unable to parse request");
GenericProxyError("Invalid request", "Proxy unable to parse your request");
return true; /* parse error */
}
/* parsing success, now let's look inside request */
LogPrint(eLogDebug, "HTTPProxy: requested: ", req.uri);
url.parse(req.uri);
if (ExtractAddressHelper(url, b64)) {
i2p::client::context.GetAddressBook ().InsertAddress (url.host, b64);
LogPrint (eLogInfo, "HTTPProxy: added b64 from addresshelper for ", url.host);
std::string full_url = url.to_string();
std::stringstream ss;
ss << "Host " << url.host << " added to router's addressbook from helper. "
<< "Click <a href=\"" << full_url << "\">here</a> to proceed.";
GenericProxyError("Addresshelper found", ss.str().c_str());
return true; /* request processed */
}
SanitizeHTTPRequest(req);
std::string dest_host = url.host;
uint16_t dest_port = url.port;
/* always set port, even if missing in request */
if (!dest_port) {
dest_port = (url.schema == "https") ? 443 : 80;
}
/* detect dest_host, set proper 'Host' header in upstream request */
auto h = req.headers.find("Host");
if (dest_host != "") {
/* absolute url, replace 'Host' header */
std::string h = dest_host;
if (dest_port != 0 && dest_port != 80)
h += ":" + std::to_string(dest_port);
req.add_header("Host", h, true);
} else if (h != req.headers.end()) {
/* relative url and 'Host' header provided. transparent proxy mode? */
i2p::http::URL u;
std::string t = "http://" + h->second;
u.parse(t);
dest_host = u.host;
dest_port = u.port;
} else {
/* relative url and missing 'Host' header */
GenericProxyError("Invalid request", "Can't detect destination host from request");
return true;
}
/* check dest_host really exists and inside I2P network */
i2p::data::IdentHash identHash;
if (str_rmatch(dest_host, ".i2p")) {
if (!i2p::client::context.GetAddressBook ().GetIdentHash (dest_host, identHash)) {
HostNotFound(dest_host);
return true; /* request processed */
}
/* TODO: outproxy handler here */
} else {
LogPrint (eLogWarning, "HTTPProxy: outproxy failure for ", dest_host, ": not implemented yet");
std::string message = "Host" + dest_host + "not inside I2P network, but outproxy support not implemented yet";
GenericProxyError("Outproxy failure", message.c_str());
return true;
}
/* make relative url */
url.schema = "";
url.host = "";
req.uri = url.to_string();
/* drop original request from recv buffer */
m_recv_buf.erase(0, req_len);
/* build new buffer from modified request and data from original request */
m_send_buf = req.to_string();
m_send_buf.append(m_recv_buf);
/* connect to destination */
LogPrint(eLogDebug, "HTTPProxy: connecting to host ", dest_host, ":", dest_port);
GetOwner()->CreateStream (std::bind (&HTTPReqHandler::HandleStreamRequestComplete,
shared_from_this(), std::placeholders::_1), dest_host, dest_port);
return true;
}
/* will be called after some data received from client */
void HTTPReqHandler::HandleSockRecv(const boost::system::error_code & ecode, std::size_t len)
{
LogPrint(eLogDebug, "HTTPProxy: sock recv: ", len, " bytes, recv buf: ", m_recv_buf.length(), ", send buf: ", m_send_buf.length());
if(ecode)
{
LogPrint(eLogWarning, "HTTPProxy: sock recv got error: ", ecode);
Terminate();
return;
}
m_recv_buf.append(reinterpret_cast<const char *>(m_recv_chunk), len);
if (HandleRequest()) {
m_recv_buf.clear();
return;
}
AsyncSockRead();
}
void HTTPReqHandler::SentHTTPFailed(const boost::system::error_code & ecode)
{
if (ecode)
LogPrint (eLogError, "HTTPProxy: Closing socket after sending failure because: ", ecode.message ());
Terminate();
}
void HTTPReqHandler::HandleStreamRequestComplete (std::shared_ptr<i2p::stream::Stream> stream)
{
if (!stream) {
LogPrint (eLogError, "HTTPProxy: error when creating the stream, check the previous warnings for more info");
GenericProxyError("Host is down", "Can't create connection to requested host, it may be down");
return;
}
if (Kill())
return;
LogPrint (eLogDebug, "HTTPProxy: Created new I2PTunnel stream, sSID=", stream->GetSendStreamID(), ", rSID=", stream->GetRecvStreamID());
auto connection = std::make_shared<i2p::client::I2PTunnelConnection>(GetOwner(), m_sock, stream);
GetOwner()->AddHandler (connection);
connection->I2PConnect (reinterpret_cast<const uint8_t*>(m_send_buf.data()), m_send_buf.length());
Done (shared_from_this());
}
HTTPProxy::HTTPProxy(const std::string& address, int port, std::shared_ptr<i2p::client::ClientDestination> localDestination):
TCPIPAcceptor(address, port, localDestination ? localDestination : i2p::client::context.GetSharedLocalDestination ())
{
}
std::shared_ptr<i2p::client::I2PServiceHandler> HTTPProxy::CreateHandler(std::shared_ptr<boost::asio::ip::tcp::socket> socket)
{
return std::make_shared<HTTPReqHandler> (this, socket);
}
} // http
} // i2p