summaryrefslogtreecommitdiffstats
path: root/sstuff.hh
blob: 208697cc2bb8e6dd501fba855082cec2414598ab (plain)
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
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
/*
 * This file is part of PowerDNS or dnsdist.
 * Copyright -- PowerDNS.COM B.V. and its contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * In addition, for the avoidance of any doubt, permission is granted to
 * link this program with OpenSSL and to (re)distribute the binaries
 * produced as the result of such linking.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
#pragma once
#include <string>
#include <sstream>
#include <iostream>
#include "iputils.hh"
#include <cerrno>
#include <sys/types.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <sys/select.h>
#include <fcntl.h>
#include <stdexcept>

#include <boost/utility.hpp>
#include <csignal>
#include "namespaces.hh"


typedef int ProtocolType; //!< Supported protocol types

//! Representation of a Socket and many of the Berkeley functions available
class Socket : public boost::noncopyable
{
public:
  Socket(int fd): d_socket(fd)
  {
  }

  //! Construct a socket of specified address family and socket type.
  Socket(int af, int st, ProtocolType pt=0)
  {
    if((d_socket=socket(af, st, pt))<0)
      throw NetworkError(stringerror());
    setCloseOnExec(d_socket);
  }

  Socket(Socket&& rhs): d_buffer(std::move(rhs.d_buffer)), d_socket(rhs.d_socket)
  {
    rhs.d_socket = -1;
  }

  Socket& operator=(Socket&& rhs)
  {
    if (d_socket != -1) {
      close(d_socket);
    }
    d_socket = rhs.d_socket;
    rhs.d_socket = -1;
    d_buffer = std::move(rhs.d_buffer);
    return *this;
  }

  ~Socket()
  {
    try {
      if (d_socket != -1) {
        closesocket(d_socket);
      }
    }
    catch(const PDNSException& e) {
    }
  }

  //! If the socket is capable of doing so, this function will wait for a connection
  std::unique_ptr<Socket> accept()
  {
    struct sockaddr_in remote;
    socklen_t remlen=sizeof(remote);
    memset(&remote, 0, sizeof(remote));
    int s=::accept(d_socket, reinterpret_cast<sockaddr *>(&remote), &remlen);
    if(s<0) {
      if(errno==EAGAIN)
        return nullptr;

      throw NetworkError("Accepting a connection: "+stringerror());
    }

    return std::make_unique<Socket>(s);
  }

  //! Get remote address
  bool getRemote(ComboAddress &remote) {
    socklen_t remotelen=sizeof(remote);
    return (getpeername(d_socket, reinterpret_cast<struct sockaddr *>(&remote), &remotelen) >= 0);
  }

  //! Check remote address against netmaskgroup ng
  bool acl(const NetmaskGroup &ng)
  {
    ComboAddress remote;
    if (getRemote(remote))
      return ng.match(remote);

    return false;
  }

  //! Set the socket to non-blocking
  void setNonBlocking()
  {
    ::setNonBlocking(d_socket);
  }

  //! Set the socket to blocking
  void setBlocking()
  {
    ::setBlocking(d_socket);
  }

  void setReuseAddr()
  {
    try {
      ::setReuseAddr(d_socket);
    } catch (const PDNSException &e) {
      throw NetworkError(e.reason);
    }
  }

  void setFastOpenConnect()
  {
#ifdef TCP_FASTOPEN_CONNECT
    int on = 1;
    if (setsockopt(d_socket, IPPROTO_TCP, TCP_FASTOPEN_CONNECT, &on, sizeof(on)) < 0) {
      throw NetworkError("While setting TCP_FASTOPEN_CONNECT: " + stringerror());
    }
#else
   throw NetworkError("While setting TCP_FASTOPEN_CONNECT: not compiled in");
#endif
  }

  //! Bind the socket to a specified endpoint
  void bind(const ComboAddress &local, bool reuseaddr=true)
  {
    int tmp=1;
    if(reuseaddr && setsockopt(d_socket, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<char*>(&tmp), sizeof tmp)<0)
      throw NetworkError("Setsockopt failed: "+stringerror());

    if(::bind(d_socket, reinterpret_cast<const struct sockaddr *>(&local), local.getSocklen())<0)
      throw NetworkError("While binding: "+stringerror());
  }

  //! Connect the socket to a specified endpoint
  void connect(const ComboAddress &ep, int timeout=0)
  {
    SConnectWithTimeout(d_socket, ep, timeval{timeout,0});
  }


  //! For datagram sockets, receive a datagram and learn where it came from
  /** For datagram sockets, receive a datagram and learn where it came from
      \param dgram Will be filled with the datagram
      \param ep Will be filled with the origin of the datagram */
  void recvFrom(string &dgram, ComboAddress &ep)
  {
    socklen_t remlen = sizeof(ep);
    ssize_t bytes;
    d_buffer.resize(s_buflen);
    if((bytes=recvfrom(d_socket, &d_buffer[0], s_buflen, 0, reinterpret_cast<sockaddr *>(&ep) , &remlen)) <0)
      throw NetworkError("After recvfrom: "+stringerror());

    dgram.assign(d_buffer, 0, static_cast<size_t>(bytes));
  }

  bool recvFromAsync(string &dgram)
  {
    struct sockaddr_in remote;
    socklen_t remlen = sizeof(remote);
    ssize_t bytes;
    d_buffer.resize(s_buflen);
    if((bytes=recvfrom(d_socket, &d_buffer[0], s_buflen, 0, reinterpret_cast<sockaddr *>(&remote), &remlen))<0) {
      if(errno!=EAGAIN) {
        throw NetworkError("After async recvfrom: "+stringerror());
      }
      else {
        return false;
      }
    }
    dgram.assign(d_buffer, 0, static_cast<size_t>(bytes));
    return true;
  }


  //! For datagram sockets, send a datagram to a destination
  void sendTo(const char* msg, size_t len, const ComboAddress &ep)
  {
    if(sendto(d_socket, msg, len, 0, reinterpret_cast<const sockaddr *>(&ep), ep.getSocklen())<0)
      throw NetworkError("After sendto: "+stringerror());
  }

  //! For connected datagram sockets, send a datagram
  void send(const std::string& msg)
  {
    if(::send(d_socket, msg.c_str(), msg.size(), 0)<0)
      throw NetworkError("After send: "+stringerror());
  }


  /** For datagram sockets, send a datagram to a destination
      \param dgram The datagram
      \param ep The intended destination of the datagram */
  void sendTo(const string &dgram, const ComboAddress &ep)
  {
    sendTo(dgram.c_str(), dgram.length(), ep);
  }


  //! Write this data to the socket, taking care that all bytes are written out
  void writen(const string &data)
  {
    if(data.empty())
      return;

    size_t toWrite=data.length();
    ssize_t res;
    const char *ptr=data.c_str();

    do {
      res=::send(d_socket, ptr, toWrite, 0);
      if(res<0)
        throw NetworkError("Writing to a socket: "+stringerror());
      if(!res)
        throw NetworkError("EOF on socket");
      toWrite -= static_cast<size_t>(res);
      ptr += static_cast<size_t>(res);
    } while(toWrite);

  }

  //! tries to write toWrite bytes from ptr to the socket
  /** tries to write toWrite bytes from ptr to the socket, but does not make sure they al get written out
      \param ptr Location to write from
      \param toWrite number of bytes to try
  */
  size_t tryWrite(const char *ptr, size_t toWrite)
  {
    ssize_t res;
    res=::send(d_socket,ptr,toWrite,0);
    if(res==0)
      throw NetworkError("EOF on writing to a socket");

    if(res>0)
      return res;

    if(errno==EAGAIN)
      return 0;

    throw NetworkError("Writing to a socket: "+stringerror());
  }

  //! Writes toWrite bytes from ptr to the socket
  /** Writes toWrite bytes from ptr to the socket. Returns how many bytes were written */
  size_t write(const char *ptr, size_t toWrite)
  {
    ssize_t res;
    res=::send(d_socket,ptr,toWrite,0);
    if(res<0) {
      throw NetworkError("Writing to a socket: "+stringerror());
    }
    return res;
  }

  void writenWithTimeout(const void *buffer, size_t n, int timeout)
  {
    size_t bytes=n;
    const char *ptr = reinterpret_cast<const char*>(buffer);
    ssize_t ret;
    while(bytes) {
      ret=::write(d_socket, ptr, bytes);
      if(ret < 0) {
        if(errno == EAGAIN) {
          ret=waitForRWData(d_socket, false, timeout, 0);
          if(ret < 0)
            throw NetworkError("Waiting for data write");
          if(!ret)
            throw NetworkError("Timeout writing data");
          continue;
        }
        else
          throw NetworkError("Writing data: "+stringerror());
      }
      if(!ret) {
        throw NetworkError("Did not fulfill TCP write due to EOF");
      }

      ptr += static_cast<size_t>(ret);
      bytes -= static_cast<size_t>(ret);
    }
  }

  //! reads one character from the socket
  int getChar()
  {
    char c;

    ssize_t res=::recv(d_socket,&c,1,0);
    if(res)
      return c;
    return -1;
  }

  void getline(string &data)
  {
    data="";
    int c;
    while((c=getChar())!=-1) {
      data+=(char)c;
      if(c=='\n')
        break;
    }
  }

  //! Reads a block of data from the socket to a string
  void read(string &data)
  {
    d_buffer.resize(s_buflen);
    ssize_t res=::recv(d_socket, &d_buffer[0], s_buflen, 0);
    if(res<0)
      throw NetworkError("Reading from a socket: "+stringerror());
    data.assign(d_buffer, 0, static_cast<size_t>(res));
  }

  //! Reads a block of data from the socket to a block of memory
  size_t read(char *buffer, size_t bytes)
  {
    ssize_t res=::recv(d_socket, buffer, bytes, 0);
    if(res<0)
      throw NetworkError("Reading from a socket: "+stringerror());
    return static_cast<size_t>(res);
  }

  /** Read a bock of data from the socket to a block of memory,
  *   waiting at most 'timeout' seconds for the data to become
  *   available. Be aware that this does _NOT_ handle partial reads
  *   for you.
  */
  ssize_t readWithTimeout(char* buffer, size_t n, int timeout)
  {
    int err = waitForRWData(d_socket, true, timeout, 0);

    if(err == 0)
      throw NetworkError("timeout reading");
    if(err < 0)
      throw NetworkError("nonblocking read failed: "+stringerror());

    return read(buffer, n);
  }

  //! Sets the socket to listen with a default listen backlog of 10 pending connections
  void listen(unsigned int length=10)
  {
    if(::listen(d_socket,length)<0)
      throw NetworkError("Setting socket to listen: "+stringerror());
  }

  //! Returns the internal file descriptor of the socket
  int getHandle() const
  {
    return d_socket;
  }

  int releaseHandle()
  {
    int ret = d_socket;
    d_socket = -1;
    return ret;
  }

private:
  static const size_t s_buflen{4096};
  std::string d_buffer;
  int d_socket;
};