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/cvs/deliantra/server/socket/lowlevel.C
Revision: 1.48
Committed: Sun Jun 24 04:09:29 2007 UTC (16 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
Changes since 1.47: +14 -10 lines
Log Message:
first rough cut of msg rewriting, introducing cfpod, a haxored pod variant for crossfire messgaes. where will it end?

File Contents

# Content
1 /*
2 * This file is part of Crossfire TRT, the Multiplayer Online Role Playing Game.
3 *
4 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
5 * Copyright (©) 1992,2007 Frank Tore Johansen
6 *
7 * Crossfire TRT is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the Free
9 * Software Foundation; either version 2 of the License, or (at your option)
10 * any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with Crossfire TRT; if not, write to the Free Software Foundation, Inc. 51
19 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 *
21 * The authors can be reached via e-mail to <crossfire@schmorp.de>
22 */
23
24 using namespace std;
25
26 #include <global.h>
27 #include <sproto.h>
28 #include <cstdarg>
29
30 #if HAVE_TCP_INFO
31 # include <sys/types.h>
32 # include <sys/socket.h>
33 # include <netinet/in.h>
34 # include <netinet/tcp.h>
35 #endif
36
37 // disconnect a socket after this many seconds without an ack
38 #define SOCKET_TIMEOUT 8.
39
40 // force a packet when idle for more than this many seconds,
41 // forcing an ack regularly.
42 #define IDLE_PING 2.
43
44 void
45 client::flush ()
46 {
47 if (destroyed ())
48 return;
49
50 #if HAVE_TCP_INFO
51 // check about once per second, spread evenly over all clients
52 // do this only when player is active
53 if (!((pticks + fd) & 7) && pl && pl->active)
54 {
55 // check time of last ack, and, if too old, kill connection
56 struct tcp_info tcpi;
57 socklen_t len = sizeof (tcpi);
58
59 if (!getsockopt (fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
60 {
61 if (tcpi.tcpi_snd_mss)
62 mss = tcpi.tcpi_snd_mss;
63
64 rtt = tcpi.tcpi_rtt;
65 rttvar = tcpi.tcpi_rttvar;
66
67 if (tcpi.tcpi_last_ack_recv > int (SOCKET_TIMEOUT * 1000))
68 {
69 send_msg (NDI_RED, "connection-timeout", "safety disconnect due to tcp/ip timeout (no packets received)");
70 write_outputbuffer ();
71
72 LOG (llevDebug, "connection on fd %d closed due to ack timeout (%u/%u/%u)\n", fd,
73 (unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
74 destroy ();
75 }
76 }
77 }
78 #endif
79
80 /**
81 * Writes data to socket.
82 *
83 * When the socket is clear to write, and we have backlogged data, this
84 * is called to write it out.
85 */
86
87 // write a nop to the socket at least every IDLE_NOP seconds.
88 if (!outputbuffer.len)
89 {
90 if (last_send + IDLE_PING <= NOW && pl && pl->active)
91 {
92 // this is a bit ugly, but map1/map1a seem to be the only
93 // nop'able commands and they are quite small.
94 packet sl (mapmode == Map1Cmd ? "map1" : "map1a");
95 send_packet (sl);
96 }
97 else
98 return;
99 }
100
101 if (socket_ev.poll () & PE_W)
102 return;
103
104 last_send = NOW;
105 write_outputbuffer ();
106 }
107
108 void
109 client::write_outputbuffer ()
110 {
111 while (outputbuffer.len)
112 {
113 int res = write (fd, outputbuffer.data + outputbuffer.start,
114 min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));
115
116 if (res > 0)
117 {
118 outputbuffer.start += res;
119 /* wrap back to start of buffer */
120 if (outputbuffer.start == SOCKETBUFSIZE)
121 outputbuffer.start = 0;
122
123 outputbuffer.len -= res;
124 }
125 else if (res == 0)
126 {
127 LOG (llevError, "socket write failed, connection closed.\n");
128 destroy ();
129 return;
130 }
131 else if (errno == EINTR)
132 {
133 // just retry
134 }
135 else if (errno == EAGAIN)
136 {
137 // delay till ready
138 socket_ev.poll (socket_ev.poll () | PE_W);
139 socket_ev.start ();
140 return;
141 }
142 else
143 {
144 LOG (llevError, "socket write failed: %s\n", strerror (errno));
145 destroy ();
146 return;
147 }
148 }
149
150 socket_ev.poll (socket_ev.poll () & ~PE_W);
151 }
152
153 /******************************************************************************
154 *
155 * Start of read routines.
156 *
157 ******************************************************************************/
158
159 int
160 client::next_packet ()
161 {
162 if (inbuf_len >= 2)
163 {
164 int pkt_len = (inbuf [0] << 8) | inbuf [1];
165
166 if (inbuf_len >= 2 + pkt_len)
167 return 2 + pkt_len;
168
169 if (inbuf_len == sizeof (inbuf))
170 {
171 send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED);
172 destroy ();
173 return -1;
174 }
175 }
176
177 return 0;
178 }
179
180 void
181 client::skip_packet (int len)
182 {
183 inbuf_len -= len;
184 memmove (inbuf, inbuf + len, inbuf_len);
185 }
186
187 /*****************************************************************************
188 * Start of command dispatch area.
189 * The commands here are protocol commands.
190 ****************************************************************************/
191
192 // SocketCommand, PlayingCommand, should not exist with those ugly casts
193 #define SC(cb) (void *)static_cast<void (*)(char *, int, client *)>(cb),
194 #define PC(cb) (void *)static_cast<void (*)(char *, int, player *)>(cb), PF_PLAYER |
195
196 /**
197 * Dispatch table for the server.
198 */
199 static struct packet_type packets[] = {
200 {"ncom", PC(NewPlayerCmd) PF_PLAYING | PF_COMMAND6 },
201 {"command", PC(PlayerCmd) PF_PLAYING | PF_COMMAND0 },
202
203 {"examine", PC(ExamineCmd) PF_PLAYING },
204 {"ex", PC(ExCmd) PF_PLAYING },
205 {"apply", PC(ApplyCmd) PF_PLAYING },
206 {"lookat", PC(LookAt) PF_PLAYING },
207 {"lock", PC(LockItem) PF_PLAYING },
208 {"mark", PC(MarkItem) PF_PLAYING },
209 {"move", PC(MoveCmd) PF_PLAYING },
210 {"ext", PC(ExtCmd) 0 }, // CF+
211 {"mapredraw", PC(MapRedrawCmd) 0 },
212 {"mapinfo", PC(MapInfoCmd) 0 }, // CF+
213
214 {"reply", SC(ReplyCmd) 0 },
215 {"exti", SC(ExtiCmd) 0 }, // CF+
216 {"addme", SC(AddMeCmd) 0 },
217 {"askface", SC(AskFaceCmd) 0 },
218 {"requestinfo", SC(RequestInfo) 0 },
219 {"setfacemode", SC(SetFaceMode) 0 },
220 {"setsound", SC(SetSound) 0 },
221 {"setup", SC(SetUp) 0 },
222 {"version", SC(VersionCmd) 0 },
223 {"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /*Added: tchize */
224 {"toggleextendedtext", SC(ToggleExtendedText) 0 }, /*Added: tchize */
225 {"asksmooth", SC(AskSmooth) 0 }, /*Added: tchize (smoothing technologies) */
226 };
227
228 bool
229 client::may_execute (const packet_type *pkt) const
230 {
231 return (!(pkt->flags & PF_PLAYER) || pl)
232 && (!(pkt->flags & PF_PLAYING) || state == ST_PLAYING);
233 }
234
235 // HACK: some commands currently should be executed
236 // even when the player is frozen. this hack detects
237 // those commands. it should be folded into may_execute,
238 // but kept seperate to emphasise the hack aspect, i.e.
239 // do it better, then remove.
240 static bool
241 always_immediate (const client *ns, const packet_type *pkt, const char *data, int len)
242 {
243 if (!(pkt->flags & (PF_COMMAND0 | PF_COMMAND6)))
244 return false;
245
246 if (!ns->pl || !ns->pl->ob || !ns->pl->ob->map)
247 return false;
248
249 if (pkt->flags & PF_COMMAND6)
250 {
251 data += 6;
252 len -= 6;
253 }
254
255 if (len > 4 && !strncmp (data, "say " , 4))
256 return true;
257 if (len > 5 && !strncmp (data, "chat ", 5))
258 return true;
259
260 return false;
261 }
262
263 void
264 client::execute (const packet_type *pkt, char *data, int datalen)
265 {
266 if (may_execute (pkt) || always_immediate (this, pkt, data, datalen))
267 {
268 //TODO: only one format
269 if (pkt->flags & PF_PLAYER)
270 ((void (*)(char *, int, player *))pkt->cb)((char *)data, datalen, pl);
271 else
272 ((void (*)(char *, int, client *))pkt->cb)((char *)data, datalen, this);
273 }
274 else
275 send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED, pkt->name);
276 }
277
278 bool
279 client::handle_packet ()
280 {
281 int pkt_len = next_packet ();
282
283 if (!pkt_len)
284 return false;
285 else if (pkt_len < 0)
286 {
287 LOG (llevError, "read error on player %s\n",
288 pl && pl->ob ? &pl->ob->name : "[anonymous]");
289 destroy ();
290 return false;
291 }
292
293 inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
294
295 /* First, break out beginning word. There are at least
296 * a few commands that do not have any paremeters. If
297 * we get such a command, don't worry about trying
298 * to break it up.
299 */
300 int datalen;
301 char *data = strchr ((char *)inbuf + 2, ' ');
302
303 if (data)
304 {
305 *data++ = 0;
306 datalen = pkt_len - (data - (char *)inbuf);
307 }
308 else
309 {
310 data = (char *)inbuf + 2; // better read garbage than segfault
311 datalen = 0;
312 }
313
314 for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
315 if (!strcmp ((char *)inbuf + 2, pkt->name))
316 {
317 if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
318 queue_command (pkt, data, datalen);
319 else
320 execute (pkt, data, datalen);
321
322 goto next_packet;
323 }
324
325 // If we get here, we didn't find a valid command.
326 send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED, (char *)inbuf + 2);
327 next_packet:
328 skip_packet (pkt_len);
329
330 // input buffer has space again
331 socket_ev.poll (socket_ev.poll () | PE_R);
332
333 return true;
334 }
335
336 // callback called when socket is either readable or writable
337 void
338 client::socket_cb (iow &w, int got)
339 {
340 //TODO remove when we have better socket cleanup logic
341 if (destroyed ())
342 {
343 socket_ev.poll (0);
344 return;
345 }
346
347 if (got & PE_W)
348 {
349 write_outputbuffer ();
350
351 if (!outputbuffer.len)
352 socket_ev.poll (socket_ev.poll () & ~PE_W);
353 }
354
355 if (got & PE_R)
356 {
357 //TODO: rate-limit tcp connection in better ways, important
358
359 int amount = sizeof (inbuf) - inbuf_len;
360
361 if (!amount)
362 {
363 // input buffer full
364 socket_ev.poll (socket_ev.poll () & ~PE_R);
365 return;
366 }
367
368 amount = read (fd, inbuf + inbuf_len, amount);
369
370 if (!amount)
371 {
372 destroy ();
373 return;
374 }
375 else if (amount < 0)
376 {
377 if (errno != EAGAIN && errno != EINTR)
378 {
379 LOG (llevError, "read error: %s\n", strerror (errno));
380 destroy ();
381 return;
382 }
383
384 // should not be here, normally
385 }
386 else
387 {
388 inbuf_len += amount;
389
390 cmd_ev.start ();
391 }
392 }
393 }
394
395 // called whenever we have additional commands to process
396 void
397 client::cmd_cb (iw &w)
398 {
399 if (handle_packet ())
400 w.start ();
401 else
402 flush ();
403 }
404
405 /*******************************************************************************
406 *
407 * Start of write related routines.
408 *
409 ******************************************************************************/
410
411 /**
412 * Adds data to a socket buffer for whatever reason.
413 *
414 * ns is the socket we are adding the data to, buf is the start of the
415 * data, and len is the number of bytes to add.
416 */
417 void
418 client::send (void *buf_, int len)
419 {
420 char *buf = (char *)buf_;
421
422 if (destroyed () || !buf)
423 return;
424
425 if (len + outputbuffer.len > SOCKETBUFSIZE)
426 {
427 LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
428 // shutdown the socket, this is safer than destroying it immediately
429 // as lots of code in the callchain might still access the map etc.
430 shutdown (fd, SHUT_RDWR);
431 return;
432 }
433
434 int avail, end;
435
436 /* data + end is where we start putting the new data. The last byte
437 * currently in use is actually data + end -1
438 */
439 end = outputbuffer.start + outputbuffer.len;
440 /* The buffer is already in a wrapped state, so adjust end */
441 if (end >= SOCKETBUFSIZE)
442 end -= SOCKETBUFSIZE;
443
444 avail = SOCKETBUFSIZE - end;
445
446 /* We can all fit it behind the current data without wrapping */
447 if (avail >= len)
448 memcpy (outputbuffer.data + end, buf, len);
449 else
450 {
451 memcpy (outputbuffer.data + end, buf, avail);
452 memcpy (outputbuffer.data, buf + avail, len - avail);
453 }
454
455 outputbuffer.len += len;
456 }
457
458 /**
459 * Takes a string of data, and writes it out to the socket. A very handy
460 * shortcut function.
461 */
462 void
463 client::send_packet (packet &sl)
464 {
465 if (destroyed ())
466 return;
467
468 if (sl.length () >= MAXSOCKBUF)
469 {
470 LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
471 /* Almost certainly we've overflowed a buffer, so quit now to make
472 * it easier to debug.
473 */
474 abort ();
475 }
476
477 if (!sl.length ())
478 return;
479
480 assert (sl.hdrlen == 2);
481
482 sl.buf_ [0] = sl.length () >> 8;
483 sl.buf_ [1] = sl.length () ;
484
485 send (sl.buf_, sl.length () + sl.hdrlen);
486 }
487
488 void
489 client::send_packet (const char *buf, int len)
490 {
491 packet sl;
492
493 sl << data (buf, len);
494 send_packet (sl);
495 }
496
497 void
498 client::send_packet (const char *buf)
499 {
500 send_packet (buf, strlen (buf));
501 }
502
503 void
504 client::send_packet_printf (const char *format, ...)
505 {
506 packet sl;
507
508 va_list ap;
509 va_start (ap, format);
510 sl.vprintf (format, ap);
511 va_end (ap);
512
513 send_packet (sl);
514 }
515
516 // returns true when the message needs special (read: perl) treatment
517 static bool
518 msg_is_special (const char *msg)
519 {
520 return msg [strcspn (msg, "<[&\n")];
521 }
522
523 void
524 client::send_msg (int color, const char *type, const char *msg)
525 {
526 if (msg_is_special (msg))
527 cfperl_send_msg (this, color, type, msg);
528 else if (can_msg)
529 send_packet_printf ("msg %d %s %s", color, type, msg);
530 else if (color < 0)
531 return; // client cannot handle this
532 else
533 send_packet_printf ("drawinfo %d %s", color, msg);
534 }
535
536 void
537 client::send_drawinfo (const char *msg, int flags)
538 {
539 send_msg (flags, "log", msg);
540 }
541
542 /***********************************************************************
543 *
544 * packet functions/utilities
545 *
546 **********************************************************************/
547
548 packet::packet (const char *name)
549 {
550 reset ();
551
552 int len = strlen (name);
553 memcpy (cur, name, len); cur += len;
554 *cur++ = ' ';
555 }
556
557 packet &packet::operator <<(const ber32 v)
558 {
559 enum { maxlen = 32 / 7 + 1};
560 uint8 buf[maxlen];
561 uint8 *p = buf + maxlen;
562 uint32 val = v.val;
563
564 *--p = val & 0x7F;
565
566 while (val > 0x7F)
567 {
568 val >>= 7;
569 *--p = (val & 0x7F) | 0x80;
570 }
571
572 return *this << data (p, buf + maxlen - p);
573 }
574
575 packet &packet::operator <<(const data &v)
576 {
577 if (room () < v.len)
578 reset ();
579 else
580 {
581 if (v.len)
582 {
583 memcpy (cur, v.ptr, v.len);
584 cur += v.len;
585 }
586 }
587
588 return *this;
589 }
590
591 packet &packet::operator <<(const data8 &v)
592 {
593 unsigned int len = min (v.len, 0x00FF);
594 return *this << uint8 (len) << data (v.ptr, len);
595 }
596
597 packet &packet::operator <<(const data16 &v)
598 {
599 unsigned int len = min (v.len, 0xFFFF);
600 return *this << uint16 (len) << data (v.ptr, len);
601 }
602
603 packet &packet::operator <<(const char *v)
604 {
605 return *this << data (v, strlen (v ? v : 0));
606 }
607
608 void
609 packet::vprintf (const char *format, va_list ap)
610 {
611 int size = room ();
612
613 int len = vsnprintf ((char *)cur, size, format, ap);
614
615 if (len >= size)
616 return reset ();
617
618 cur += len;
619 }
620