1 |
|
2 |
/* |
3 |
* static char *rcsid_sockets_c = |
4 |
* "$Id: lowlevel.C,v 1.4 2006-08-30 16:30:37 root Exp $"; |
5 |
*/ |
6 |
|
7 |
/* |
8 |
CrossFire, A Multiplayer game for X-windows |
9 |
|
10 |
Copyright (C) 1992 Frank Tore Johansen |
11 |
|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
14 |
the Free Software Foundation; either version 2 of the License, or |
15 |
(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
18 |
but WITHOUT ANY WARRANTY; without even the implied warranty of |
19 |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
23 |
along with this program; if not, write to the Free Software |
24 |
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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|
26 |
The author can be reached via e-mail to mark@pyramid.com |
27 |
*/ |
28 |
|
29 |
/** |
30 |
* \file |
31 |
* Low-level socket-related functions. |
32 |
* |
33 |
* \date 2003-12-02 |
34 |
* |
35 |
* Contains some base functions that both the client and server |
36 |
* can use. As such, depending what we are being compiled for will |
37 |
* determine what we can include. the client is designed have |
38 |
* CFCLIENT defined as part of its compile flags. |
39 |
*/ |
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|
41 |
using namespace std; |
42 |
|
43 |
#include <global.h> |
44 |
#include <newclient.h> |
45 |
#include <sproto.h> |
46 |
|
47 |
#ifdef __linux__ |
48 |
# include <sys/types.h> |
49 |
# include <sys/socket.h> |
50 |
# include <netinet/in.h> |
51 |
# define TCP_HZ 1000 // sorry... |
52 |
# include <netinet/tcp.h> |
53 |
#endif |
54 |
|
55 |
// use a really low timeout, as it doesn't cost any bandwidth, and you can |
56 |
// easily die in 20 seconds... |
57 |
#define SOCKET_TIMEOUT1 10 |
58 |
#define SOCKET_TIMEOUT2 20 |
59 |
|
60 |
void |
61 |
Socket_Flush (NewSocket * ns) |
62 |
{ |
63 |
#ifdef __linux__ |
64 |
// check time of last ack, and, if too old, kill connection |
65 |
struct tcp_info tcpi; |
66 |
socklen_t len = sizeof (tcpi); |
67 |
|
68 |
if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi)) |
69 |
{ |
70 |
unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent; |
71 |
|
72 |
if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s |
73 |
&& SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent) // no data sent for 10s |
74 |
{ |
75 |
LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd, |
76 |
(unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked); |
77 |
ns->status = Ns_Dead; |
78 |
} |
79 |
} |
80 |
|
81 |
int val; |
82 |
|
83 |
val = 0; |
84 |
setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val)); |
85 |
val = 1; |
86 |
setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val)); |
87 |
#endif |
88 |
} |
89 |
|
90 |
/*********************************************************************** |
91 |
* |
92 |
* SockList functions/utilities |
93 |
* |
94 |
**********************************************************************/ |
95 |
|
96 |
void |
97 |
SockList_Init (SockList * sl) |
98 |
{ |
99 |
sl->len = 0; |
100 |
sl->buf = NULL; |
101 |
} |
102 |
|
103 |
void |
104 |
SockList_AddInt (SockList * sl, uint32 data) |
105 |
{ |
106 |
sl->buf[sl->len++] = (data >> 24) & 0xff; |
107 |
sl->buf[sl->len++] = (data >> 16) & 0xff; |
108 |
sl->buf[sl->len++] = (data >> 8) & 0xff; |
109 |
sl->buf[sl->len++] = data & 0xff; |
110 |
} |
111 |
|
112 |
void |
113 |
SockList_AddInt64 (SockList * sl, uint64 data) |
114 |
{ |
115 |
sl->buf[sl->len++] = (char) ((data >> 56) & 0xff); |
116 |
sl->buf[sl->len++] = (char) ((data >> 48) & 0xff); |
117 |
sl->buf[sl->len++] = (char) ((data >> 40) & 0xff); |
118 |
sl->buf[sl->len++] = (char) ((data >> 32) & 0xff); |
119 |
|
120 |
sl->buf[sl->len++] = (char) ((data >> 24) & 0xff); |
121 |
sl->buf[sl->len++] = (char) ((data >> 16) & 0xff); |
122 |
sl->buf[sl->len++] = (char) ((data >> 8) & 0xff); |
123 |
sl->buf[sl->len++] = (char) (data & 0xff); |
124 |
} |
125 |
|
126 |
/* Basically does the reverse of SockList_AddInt, but on |
127 |
* strings instead. Same for the GetShort, but for 16 bits. |
128 |
*/ |
129 |
int |
130 |
GetInt_String (unsigned char *data) |
131 |
{ |
132 |
return ((data[0] << 24) + (data[1] << 16) + (data[2] << 8) + data[3]); |
133 |
} |
134 |
|
135 |
short |
136 |
GetShort_String (unsigned char *data) |
137 |
{ |
138 |
return ((data[0] << 8) + data[1]); |
139 |
} |
140 |
|
141 |
/****************************************************************************** |
142 |
* |
143 |
* Start of read routines. |
144 |
* |
145 |
******************************************************************************/ |
146 |
|
147 |
/** |
148 |
* This reads from fd and puts the data in sl. We return true if we think |
149 |
* we have a full packet, 0 if we have a partial packet. The only processing |
150 |
* we do is remove the intial size value. len (As passed) is the size of the |
151 |
* buffer allocated in the socklist. We make the assumption the buffer is |
152 |
* at least 2 bytes long. |
153 |
*/ |
154 |
|
155 |
int |
156 |
SockList_ReadPacket (int fd, SockList * sl, int len) |
157 |
{ |
158 |
int stat, toread; |
159 |
|
160 |
/* Sanity check - shouldn't happen */ |
161 |
if (sl->len < 0) |
162 |
{ |
163 |
abort (); |
164 |
} |
165 |
/* We already have a partial packet */ |
166 |
if (sl->len < 2) |
167 |
{ |
168 |
#ifdef WIN32 /* ***WIN32 SockList_ReadPacket: change read() to recv() */ |
169 |
|
170 |
stat = recv (fd, sl->buf + sl->len, 2 - sl->len, 0); |
171 |
|
172 |
#else |
173 |
do |
174 |
{ |
175 |
stat = read (fd, sl->buf + sl->len, 2 - sl->len); |
176 |
} |
177 |
while ((stat == -1) && (errno == EINTR)); |
178 |
#endif |
179 |
if (stat < 0) |
180 |
{ |
181 |
/* In non blocking mode, EAGAIN is set when there is no |
182 |
* data available. |
183 |
*/ |
184 |
#ifdef WIN32 /* ***WIN32 SockList_ReadPacket: error handling for win32 */ |
185 |
if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK) |
186 |
{ |
187 |
if (WSAGetLastError () == WSAECONNRESET) |
188 |
LOG (llevDebug, "Connection closed by client\n"); |
189 |
else |
190 |
{ |
191 |
LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ()); |
192 |
} |
193 |
return -1; /* kick this user! */ |
194 |
} |
195 |
#else |
196 |
if (errno != EAGAIN && errno != EWOULDBLOCK) |
197 |
{ |
198 |
LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno)); |
199 |
} |
200 |
#endif |
201 |
return 0; /*Error */ |
202 |
} |
203 |
if (stat == 0) |
204 |
return -1; |
205 |
sl->len += stat; |
206 |
#ifdef CS_LOGSTATS |
207 |
cst_tot.ibytes += stat; |
208 |
cst_lst.ibytes += stat; |
209 |
#endif |
210 |
if (stat < 2) |
211 |
return 0; /* Still don't have a full packet */ |
212 |
} |
213 |
/* Figure out how much more data we need to read. Add 2 from the |
214 |
* end of this - size header information is not included. |
215 |
*/ |
216 |
toread = 2 + (sl->buf[0] << 8) + sl->buf[1] - sl->len; |
217 |
if ((toread + sl->len) >= len) |
218 |
{ |
219 |
LOG (llevError, "SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n", toread + sl->len, len); |
220 |
/* Quick hack in case for 'oldsocketmode' input. If we are |
221 |
* closing the socket anyways, then reading this extra 100 bytes |
222 |
* shouldn't hurt. |
223 |
*/ |
224 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */ |
225 |
recv (fd, sl->buf + 2, 100, 0); |
226 |
#else |
227 |
read (fd, sl->buf + 2, 100); |
228 |
#endif /* end win32 */ |
229 |
|
230 |
/* return error so the socket is closed */ |
231 |
return -1; |
232 |
} |
233 |
do |
234 |
{ |
235 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */ |
236 |
stat = recv (fd, sl->buf + sl->len, toread, 0); |
237 |
#else |
238 |
do |
239 |
{ |
240 |
stat = read (fd, sl->buf + sl->len, toread); |
241 |
} |
242 |
while ((stat < 0) && (errno == EINTR)); |
243 |
#endif |
244 |
if (stat < 0) |
245 |
{ |
246 |
|
247 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change error handling for win32 */ |
248 |
if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK) |
249 |
{ |
250 |
if (WSAGetLastError () == WSAECONNRESET) |
251 |
LOG (llevDebug, "Connection closed by client\n"); |
252 |
else |
253 |
{ |
254 |
LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ()); |
255 |
} |
256 |
return -1; /* kick this user! */ |
257 |
} |
258 |
#else |
259 |
if (errno != EAGAIN && errno != EWOULDBLOCK) |
260 |
{ |
261 |
LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno)); |
262 |
} |
263 |
#endif |
264 |
return 0; /*Error */ |
265 |
} |
266 |
if (stat == 0) |
267 |
return -1; |
268 |
sl->len += stat; |
269 |
#ifdef CS_LOGSTATS |
270 |
cst_tot.ibytes += stat; |
271 |
cst_lst.ibytes += stat; |
272 |
#endif |
273 |
toread -= stat; |
274 |
if (toread == 0) |
275 |
return 1; |
276 |
if (toread < 0) |
277 |
{ |
278 |
LOG (llevError, "SockList_ReadPacket: Read more bytes than desired.\n"); |
279 |
return 1; |
280 |
} |
281 |
} |
282 |
while (toread > 0); |
283 |
return 0; |
284 |
} |
285 |
|
286 |
/******************************************************************************* |
287 |
* |
288 |
* Start of write related routines. |
289 |
* |
290 |
******************************************************************************/ |
291 |
|
292 |
/** |
293 |
* Adds data to a socket buffer for whatever reason. |
294 |
* |
295 |
* ns is the socket we are adding the data to, buf is the start of the |
296 |
* data, and len is the number of bytes to add. |
297 |
*/ |
298 |
|
299 |
static void |
300 |
add_to_buffer (NewSocket * ns, char *buf, int len) |
301 |
{ |
302 |
int avail, end; |
303 |
|
304 |
if ((len + ns->outputbuffer.len) > SOCKETBUFSIZE) |
305 |
{ |
306 |
LOG (llevDebug, "Socket on fd %d has overrun internal buffer - marking as dead\n", ns->fd); |
307 |
ns->status = Ns_Dead; |
308 |
return; |
309 |
} |
310 |
|
311 |
/* data + end is where we start putting the new data. The last byte |
312 |
* currently in use is actually data + end -1 |
313 |
*/ |
314 |
|
315 |
end = ns->outputbuffer.start + ns->outputbuffer.len; |
316 |
/* The buffer is already in a wrapped state, so adjust end */ |
317 |
if (end >= SOCKETBUFSIZE) |
318 |
end -= SOCKETBUFSIZE; |
319 |
avail = SOCKETBUFSIZE - end; |
320 |
|
321 |
/* We can all fit it behind the current data without wrapping */ |
322 |
if (avail >= len) |
323 |
{ |
324 |
memcpy (ns->outputbuffer.data + end, buf, len); |
325 |
} |
326 |
else |
327 |
{ |
328 |
memcpy (ns->outputbuffer.data + end, buf, avail); |
329 |
memcpy (ns->outputbuffer.data, buf + avail, len - avail); |
330 |
} |
331 |
ns->outputbuffer.len += len; |
332 |
#if 0 |
333 |
LOG (llevDebug, "Added %d to output buffer, total length now %d, start=%d\n", len, ns->outputbuffer.len, ns->outputbuffer.start); |
334 |
#endif |
335 |
} |
336 |
|
337 |
/** |
338 |
* Writes data to socket. |
339 |
* |
340 |
* When the socket is clear to write, and we have backlogged data, this |
341 |
* is called to write it out. |
342 |
*/ |
343 |
void |
344 |
write_socket_buffer (NewSocket * ns) |
345 |
{ |
346 |
int amt, max; |
347 |
|
348 |
if (ns->outputbuffer.len == 0) |
349 |
{ |
350 |
LOG (llevDebug, "write_socket_buffer called when there is no data, fd=%d\n", ns->fd); |
351 |
return; |
352 |
} |
353 |
|
354 |
do |
355 |
{ |
356 |
max = SOCKETBUFSIZE - ns->outputbuffer.start; |
357 |
if (ns->outputbuffer.len < max) |
358 |
max = ns->outputbuffer.len; |
359 |
|
360 |
#ifdef WIN32 /* ***win32 write_socket_buffer: change write() to send() */ |
361 |
amt = send (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max, 0); |
362 |
#else |
363 |
do |
364 |
{ |
365 |
amt = write (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max); |
366 |
} |
367 |
while ((amt < 0) && (errno == EINTR)); |
368 |
#endif |
369 |
|
370 |
if (amt < 0) |
371 |
{ /* We got an error */ |
372 |
|
373 |
#ifdef WIN32 /* ***win32 write_socket_buffer: change error handling */ |
374 |
if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK) |
375 |
{ |
376 |
LOG (llevError, "New socket write failed (wsb) (%d).\n", WSAGetLastError ()); |
377 |
#else |
378 |
if (errno != EWOULDBLOCK) |
379 |
{ |
380 |
LOG (llevError, "New socket write failed (wsb) (%d: %s).\n", errno, strerror (errno)); |
381 |
#endif |
382 |
ns->status = Ns_Dead; |
383 |
return; |
384 |
} |
385 |
else |
386 |
{ /* EWOULDBLOCK */ |
387 |
/* can't write it, so store it away. */ |
388 |
ns->can_write = 0; |
389 |
return; |
390 |
} |
391 |
} |
392 |
ns->outputbuffer.start += amt; |
393 |
/* wrap back to start of buffer */ |
394 |
if (ns->outputbuffer.start == SOCKETBUFSIZE) |
395 |
ns->outputbuffer.start = 0; |
396 |
ns->outputbuffer.len -= amt; |
397 |
#ifdef CS_LOGSTATS |
398 |
cst_tot.obytes += amt; |
399 |
cst_lst.obytes += amt; |
400 |
#endif |
401 |
} |
402 |
while (ns->outputbuffer.len > 0); |
403 |
} |
404 |
|
405 |
/** |
406 |
* This writes data to the socket. - It is very low level - |
407 |
* all we try and do is write out the data to the socket |
408 |
* provided (ns). buf is the data to write, len is the number |
409 |
* of bytes to write. IT doesn't return anything - rather, it |
410 |
* updates the ns structure if we get an error. |
411 |
*/ |
412 |
void |
413 |
Write_To_Socket (NewSocket * ns, char *buf, int len) |
414 |
{ |
415 |
int amt = 0; |
416 |
char *pos = buf; |
417 |
|
418 |
if (ns->status == Ns_Dead || !buf) |
419 |
{ |
420 |
LOG (llevDebug, "Write_To_Socket called with dead socket\n"); |
421 |
return; |
422 |
} |
423 |
|
424 |
#ifndef __GNU__ /* This caused problems on Hurd */ |
425 |
if (!ns->can_write) |
426 |
{ |
427 |
add_to_buffer (ns, buf, len); |
428 |
return; |
429 |
} |
430 |
#endif |
431 |
/* If we manage to write more than we wanted, take it as a bonus */ |
432 |
while (len > 0) |
433 |
{ |
434 |
|
435 |
#ifdef WIN32 /* ***win32 Write_To_Socket: change write() to send() */ |
436 |
amt = send (ns->fd, pos, len, 0); |
437 |
#else |
438 |
do |
439 |
{ |
440 |
amt = write (ns->fd, pos, len); |
441 |
} |
442 |
while ((amt < 0) && (errno == EINTR)); |
443 |
#endif |
444 |
|
445 |
if (amt < 0) |
446 |
{ /* We got an error */ |
447 |
#ifdef WIN32 /* ***win32 Write_To_Socket: change error handling */ |
448 |
if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK) |
449 |
{ |
450 |
LOG (llevError, "New socket write failed WTS (%d).\n", WSAGetLastError ()); |
451 |
#else |
452 |
if (errno != EWOULDBLOCK) |
453 |
{ |
454 |
LOG (llevError, "New socket write failed WTS (%d: %s).\n", /* ---WIN32 */ |
455 |
errno, strerror (errno)); |
456 |
#endif |
457 |
ns->status = Ns_Dead; |
458 |
return; |
459 |
} |
460 |
else |
461 |
{ /* EWOULDBLOCK */ |
462 |
/* can't write it, so store it away. */ |
463 |
add_to_buffer (ns, pos, len); |
464 |
ns->can_write = 0; |
465 |
return; |
466 |
} |
467 |
} |
468 |
/* amt gets set to 0 above in blocking code, so we do this as |
469 |
* an else if to make sure we don't reprocess it. |
470 |
*/ |
471 |
else if (amt == 0) |
472 |
{ |
473 |
LOG (llevError, "Write_To_Socket: No data written out.\n"); |
474 |
} |
475 |
len -= amt; |
476 |
pos += amt; |
477 |
#ifdef CS_LOGSTATS |
478 |
cst_tot.obytes += amt; |
479 |
cst_lst.obytes += amt; |
480 |
#endif |
481 |
} |
482 |
} |
483 |
|
484 |
|
485 |
/** |
486 |
* Takes a string of data, and writes it out to the socket. A very handy |
487 |
* shortcut function. |
488 |
*/ |
489 |
void |
490 |
cs_write_string (NewSocket * ns, const char *buf, int len) |
491 |
{ |
492 |
SockList sl; |
493 |
|
494 |
sl.len = len; |
495 |
sl.buf = (unsigned char *) buf; |
496 |
Send_With_Handling (ns, &sl); |
497 |
} |
498 |
|
499 |
|
500 |
/** |
501 |
* Calls Write_To_Socket to send data to the client. |
502 |
* |
503 |
* The only difference in this function is that we take a SockList |
504 |
*, and we prepend the length information. |
505 |
*/ |
506 |
void |
507 |
Send_With_Handling (NewSocket * ns, SockList * msg) |
508 |
{ |
509 |
unsigned char sbuf[4]; |
510 |
|
511 |
if (ns->status == Ns_Dead || !msg) |
512 |
return; |
513 |
|
514 |
if (msg->len >= MAXSOCKBUF) |
515 |
{ |
516 |
LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", msg->len); |
517 |
/* Almost certainly we've overflowed a buffer, so quite now to make |
518 |
* it easier to debug. |
519 |
*/ |
520 |
abort (); |
521 |
} |
522 |
sbuf[0] = ((uint32) (msg->len) >> 8) & 0xFF; |
523 |
sbuf[1] = ((uint32) (msg->len)) & 0xFF; |
524 |
if (ns->status != Ns_Old) |
525 |
Write_To_Socket (ns, (char *) sbuf, 2); |
526 |
Write_To_Socket (ns, (char *) msg->buf, msg->len); |
527 |
} |
528 |
|
529 |
/** |
530 |
* Takes a string of data, and writes it out to the socket. A very handy |
531 |
* shortcut function. |
532 |
*/ |
533 |
void |
534 |
Write_String_To_Socket (NewSocket * ns, char *buf, int len) |
535 |
{ |
536 |
SockList sl; |
537 |
|
538 |
sl.len = len; |
539 |
sl.buf = (unsigned char *) buf; |
540 |
Send_With_Handling (ns, &sl); |
541 |
} |
542 |
|
543 |
|
544 |
/****************************************************************************** |
545 |
* |
546 |
* statistics logging functions. |
547 |
* |
548 |
******************************************************************************/ |
549 |
|
550 |
#ifdef CS_LOGSTATS |
551 |
|
552 |
/* cst_tot is for the life of the server, cst_last is for the last series of |
553 |
* stats |
554 |
*/ |
555 |
CS_Stats cst_tot, cst_lst; |
556 |
|
557 |
/** |
558 |
* Writes out the gathered stats. We clear cst_lst. |
559 |
*/ |
560 |
void |
561 |
write_cs_stats (void) |
562 |
{ |
563 |
time_t now = time (NULL); |
564 |
|
565 |
/* If no connections recently, don't both to log anything */ |
566 |
if (cst_lst.ibytes == 0 && cst_lst.obytes == 0) |
567 |
return; |
568 |
|
569 |
/* CSSTAT is put in so scripts can easily find the line */ |
570 |
LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n", |
571 |
ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn, |
572 |
now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start); |
573 |
cst_lst.ibytes = 0; |
574 |
cst_lst.obytes = 0; |
575 |
cst_lst.max_conn = socket_info.nconns; |
576 |
cst_lst.time_start = now; |
577 |
} |
578 |
#endif |