trunk/src/packet.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2014 ircd-hybrid development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  USA
 */

/*! \file packet.c
 * \brief Packet handlers.
 * \version $Id$
 */

#include "stdinc.h"
#include "list.h"
#include "s_bsd.h"
#include "conf.h"
#include "s_serv.h"
#include "client.h"
#include "ircd.h"
#include "parse.h"
#include "fdlist.h"
#include "packet.h"
#include "irc_string.h"
#include "memory.h"
#include "hook.h"
#include "send.h"
#include "s_misc.h"

#define READBUF_SIZE 16384

static char readBuf[READBUF_SIZE];
static void client_dopacket(struct Client *, char *, size_t);

/* extract_one_line()
 *
 * inputs       - pointer to a dbuf queue
 *              - pointer to buffer to copy data to
 * output       - length of <buffer>
 * side effects - one line is copied and removed from the dbuf
 */
static int
extract_one_line(struct dbuf_queue *qptr, char *buffer)
{
  struct dbuf_block *block;
  int line_bytes = 0, empty_bytes = 0, phase = 0;
  unsigned int idx;

  char c;
  dlink_node *ptr;

  /*
   * Phase 0: "empty" characters before the line
   * Phase 1: copying the line
   * Phase 2: "empty" characters after the line
   *          (delete them as well and free some space in the dbuf)
   *
   * Empty characters are CR, LF and space (but, of course, not
   * in the middle of a line). We try to remove as much of them as we can,
   * since they simply eat server memory.
   *
   * --adx
   */
  DLINK_FOREACH(ptr, qptr->blocks.head)
  {
    block = ptr->data;

    for (idx = 0; idx < block->size; idx++)
    {
      c = block->data[idx];
      if (IsEol(c) || (c == ' ' && phase != 1))
      {
        empty_bytes++;
        if (phase == 1)
          phase = 2;
      }
      else switch (phase)
      {
        case 0: phase = 1;
        case 1: if (line_bytes++ < IRCD_BUFSIZE - 2)
                  *buffer++ = c;
                break;
        case 2: *buffer = '\0';
                dbuf_delete(qptr, line_bytes + empty_bytes);
                return IRCD_MIN(line_bytes, IRCD_BUFSIZE - 2);
      }
    }
  }

  /*
   * Now, if we haven't reached phase 2, ignore all line bytes
   * that we have read, since this is a partial line case.
   */
  if (phase != 2)
    line_bytes = 0;
  else
    *buffer = '\0';

  /* Remove what is now unnecessary */
  dbuf_delete(qptr, line_bytes + empty_bytes);
  return IRCD_MIN(line_bytes, IRCD_BUFSIZE - 2);
}

/*
 * parse_client_queued - parse client queued messages
 */
static void
parse_client_queued(struct Client *client_p)
{
  int dolen = 0;
  int checkflood = 1;
  struct LocalUser *lclient_p = client_p->localClient;

  if (IsUnknown(client_p))
  {
    int i = 0;

    for (; ;)
    {
      if (IsDefunct(client_p))
        return;

      /* rate unknown clients at MAX_FLOOD per loop */
      if (i >= MAX_FLOOD)
        break;

      dolen = extract_one_line(&lclient_p->buf_recvq, readBuf);
      if (dolen == 0)
        break;

      client_dopacket(client_p, readBuf, dolen);
      i++;

      /* if they've dropped out of the unknown state, break and move
       * to the parsing for their appropriate status.  --fl
       */
      if(!IsUnknown(client_p))
        break;
    }
  }

  if (IsServer(client_p) || IsConnecting(client_p) || IsHandshake(client_p))
  {
    while (1)
    {
      if (IsDefunct(client_p))
        return;
      if ((dolen = extract_one_line(&lclient_p->buf_recvq,
                                    readBuf)) == 0)
        break;
      client_dopacket(client_p, readBuf, dolen);
    }
  }
  else if (IsClient(client_p))
  {
    if (ConfigFileEntry.no_oper_flood && (HasUMode(client_p, UMODE_OPER) || IsCanFlood(client_p)))
    {
      if (ConfigFileEntry.true_no_oper_flood)
        checkflood = -1;
      else
        checkflood = 0;
    }

    /*
     * Handle flood protection here - if we exceed our flood limit on
     * messages in this loop, we simply drop out of the loop prematurely.
     *   -- adrian
     */
    for (; ;)
    {
      if (IsDefunct(client_p))
        break;

      /* This flood protection works as follows:
       *
       * A client is given allow_read lines to send to the server.  Every
       * time a line is parsed, sent_parsed is increased.  sent_parsed
       * is decreased by 1 every time flood_recalc is called.
       *
       * Thus a client can 'burst' allow_read lines to the server, any
       * excess lines will be parsed one per flood_recalc() call.
       *
       * Therefore a client will be penalised more if they keep flooding,
       * as sent_parsed will always hover around the allow_read limit
       * and no 'bursts' will be permitted.
       */
      if (checkflood > 0)
      {
        if(lclient_p->sent_parsed >= lclient_p->allow_read)
          break;
      }

      /* allow opers 4 times the amount of messages as users. why 4?
       * why not. :) --fl_
       */
      else if (lclient_p->sent_parsed >= (4 * lclient_p->allow_read) &&
               checkflood != -1)
        break;

      dolen = extract_one_line(&lclient_p->buf_recvq, readBuf);
      if (dolen == 0)
        break;

      client_dopacket(client_p, readBuf, dolen);
      lclient_p->sent_parsed++;
    }
  }
}

/* flood_endgrace()
 *
 * marks the end of the clients grace period
 */
void
flood_endgrace(struct Client *client_p)
{
  SetFloodDone(client_p);

  /* Drop their flood limit back down */
  client_p->localClient->allow_read = MAX_FLOOD;

  /* sent_parsed could be way over MAX_FLOOD but under MAX_FLOOD_BURST,
   * so reset it.
   */
  client_p->localClient->sent_parsed = 0;
}

/*
 * flood_recalc
 *
 * recalculate the number of allowed flood lines. this should be called
 * once a second on any given client. We then attempt to flush some data.
 */
void
flood_recalc(fde_t *fd, void *data)
{
  struct Client *client_p = data;
  struct LocalUser *lclient_p = client_p->localClient;

  /* allow a bursting client their allocation per second, allow
   * a client whos flooding an extra 2 per second
   */
  if (IsFloodDone(client_p))
    lclient_p->sent_parsed -= 2;
  else
    lclient_p->sent_parsed = 0;

  if (lclient_p->sent_parsed < 0)
    lclient_p->sent_parsed = 0;

  parse_client_queued(client_p);

  /* And now, try flushing .. */
  if (!IsDead(client_p))
  {
    /* and finally, reset the flood check */
    comm_setflush(fd, 1000, flood_recalc, client_p);
  }
}

/*
 * read_packet - Read a 'packet' of data from a connection and process it.
 */
void
read_packet(fde_t *fd, void *data)
{
  struct Client *client_p = data;
  int length = 0;

  if (IsDefunct(client_p))
    return;

  /*
   * Read some data. We *used to* do anti-flood protection here, but
   * I personally think it makes the code too hairy to make sane.
   *     -- adrian
   */
  do
  {
#ifdef HAVE_LIBCRYPTO
    if (fd->ssl)
    {
      length = SSL_read(fd->ssl, readBuf, READBUF_SIZE);

      /* translate openssl error codes, sigh */
      if (length < 0)
        switch (SSL_get_error(fd->ssl, length))
        {
          case SSL_ERROR_WANT_WRITE:
            comm_setselect(fd, COMM_SELECT_WRITE, (PF *)sendq_unblocked, client_p, 0);
            return;
          case SSL_ERROR_WANT_READ:
              errno = EWOULDBLOCK;
          case SSL_ERROR_SYSCALL:
              break;
          case SSL_ERROR_SSL:
            if (errno == EAGAIN)
              break;
          default:
            length = errno = 0;
        }
    }
    else
#endif
    {
      length = recv(fd->fd, readBuf, READBUF_SIZE, 0);
    }

    if (length <= 0)
    {
      /*
       * If true, then we can recover from this error.  Just jump out of
       * the loop and re-register a new io-request.
       */
      if (length < 0 && ignoreErrno(errno))
        break;

      dead_link_on_read(client_p, length);
      return;
    }

    dbuf_put(&client_p->localClient->buf_recvq, readBuf, length);

    if (client_p->localClient->lasttime < CurrentTime)
      client_p->localClient->lasttime = CurrentTime;
    if (client_p->localClient->lasttime > client_p->localClient->since)
      client_p->localClient->since = CurrentTime;
    ClearPingSent(client_p);

    /* Attempt to parse what we have */
    parse_client_queued(client_p);

    if (IsDefunct(client_p))
      return;

    /* Check to make sure we're not flooding */
    if (!(IsServer(client_p) || IsHandshake(client_p) || IsConnecting(client_p))
        && (dbuf_length(&client_p->localClient->buf_recvq) >
            get_recvq(&client_p->localClient->confs)))
    {
      if (!(ConfigFileEntry.no_oper_flood && HasUMode(client_p, UMODE_OPER)))
      {
        exit_client(client_p, client_p, "Excess Flood");
        return;
      }
    }
  }
#ifdef HAVE_LIBCRYPTO
  while (length == sizeof(readBuf) || fd->ssl);
#else
  while (length == sizeof(readBuf));
#endif

  /* If we get here, we need to register for another COMM_SELECT_READ */
  comm_setselect(fd, COMM_SELECT_READ, read_packet, client_p, 0);
}

/*
 * client_dopacket - copy packet to client buf and parse it
 *      client_p - pointer to client structure for which the buffer data
 *             applies.
 *      buffer - pointr to the buffer containing the newly read data
 *      length - number of valid bytes of data in the buffer
 *
 * Note:
 *      It is implicitly assumed that dopacket is called only
 *      with client_p of "local" variation, which contains all the
 *      necessary fields (buffer etc..)
 */
static void
client_dopacket(struct Client *client_p, char *buffer, size_t length)
{
  /*
   * Update messages received
   */
  ++me.localClient->recv.messages;
  ++client_p->localClient->recv.messages;

  /*
   * Update bytes received
   */
  client_p->localClient->recv.bytes += length;
  me.localClient->recv.bytes += length;

  parse(client_p, buffer, buffer + length);
}
Revision:	2916
Committed:	Sat Jan 25 21:09:18 2014 UTC (11 years, 7 months ago) by michael
Content type:	text/x-csrc
File size:	10512 byte(s)
Log Message:	- Clean up all files in include/ (fixed indentation, removed whitespaces/tabs) - Fixed copyright years
#	User	Rev	Content
1	adx	30	/*
2	michael	2916	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	adx	30	*
4	michael	2916	* Copyright (c) 1997-2014 ircd-hybrid development team
5	adx	30	*
6			* This program is free software; you can redistribute it and/or modify
7			* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation; either version 2 of the License, or
9			* (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19			* USA
20			*/
21	michael	2916
22			/*! \file packet.c
23			* \brief Packet handlers.
24			* \version $Id$
25			*/
26
27	adx	30	#include "stdinc.h"
28	michael	1011	#include "list.h"
29	adx	30	#include "s_bsd.h"
30	michael	1309	#include "conf.h"
31	adx	30	#include "s_serv.h"
32			#include "client.h"
33			#include "ircd.h"
34			#include "parse.h"
35			#include "fdlist.h"
36			#include "packet.h"
37			#include "irc_string.h"
38			#include "memory.h"
39			#include "hook.h"
40			#include "send.h"
41	michael	1243	#include "s_misc.h"
42	adx	30
43			#define READBUF_SIZE 16384
44
45			static char readBuf[READBUF_SIZE];
46			static void client_dopacket(struct Client , char , size_t);
47
48			/* extract_one_line()
49			*
50			* inputs - pointer to a dbuf queue
51			* - pointer to buffer to copy data to
52			* output - length of <buffer>
53			* side effects - one line is copied and removed from the dbuf
54			*/
55			static int
56			extract_one_line(struct dbuf_queue qptr, char buffer)
57			{
58			struct dbuf_block *block;
59			int line_bytes = 0, empty_bytes = 0, phase = 0;
60			unsigned int idx;
61
62			char c;
63			dlink_node *ptr;
64
65			/*
66			* Phase 0: "empty" characters before the line
67			* Phase 1: copying the line
68			* Phase 2: "empty" characters after the line
69			* (delete them as well and free some space in the dbuf)
70			*
71			* Empty characters are CR, LF and space (but, of course, not
72			* in the middle of a line). We try to remove as much of them as we can,
73			* since they simply eat server memory.
74			*
75			* --adx
76			*/
77			DLINK_FOREACH(ptr, qptr->blocks.head)
78			{
79			block = ptr->data;
80
81			for (idx = 0; idx < block->size; idx++)
82			{
83			c = block->data[idx];
84			if (IsEol(c) \|\| (c == ' ' && phase != 1))
85			{
86			empty_bytes++;
87			if (phase == 1)
88			phase = 2;
89			}
90			else switch (phase)
91			{
92			case 0: phase = 1;
93			case 1: if (line_bytes++ < IRCD_BUFSIZE - 2)
94			*buffer++ = c;
95			break;
96			case 2: *buffer = '\0';
97			dbuf_delete(qptr, line_bytes + empty_bytes);
98			return IRCD_MIN(line_bytes, IRCD_BUFSIZE - 2);
99			}
100			}
101			}
102
103			/*
104			* Now, if we haven't reached phase 2, ignore all line bytes
105			* that we have read, since this is a partial line case.
106			*/
107			if (phase != 2)
108			line_bytes = 0;
109			else
110			*buffer = '\0';
111
112			/* Remove what is now unnecessary */
113			dbuf_delete(qptr, line_bytes + empty_bytes);
114			return IRCD_MIN(line_bytes, IRCD_BUFSIZE - 2);
115			}
116
117			/*
118			* parse_client_queued - parse client queued messages
119			*/
120			static void
121			parse_client_queued(struct Client *client_p)
122	michael	2916	{
123	adx	30	int dolen = 0;
124			int checkflood = 1;
125			struct LocalUser *lclient_p = client_p->localClient;
126
127			if (IsUnknown(client_p))
128			{
129			int i = 0;
130
131	michael	2916	for (; ;)
132	adx	30	{
133			if (IsDefunct(client_p))
134	michael	2916	return;
135	adx	30
136			/* rate unknown clients at MAX_FLOOD per loop */
137			if (i >= MAX_FLOOD)
138			break;
139
140			dolen = extract_one_line(&lclient_p->buf_recvq, readBuf);
141			if (dolen == 0)
142	michael	2916	break;
143	adx	30
144			client_dopacket(client_p, readBuf, dolen);
145			i++;
146
147			/* if they've dropped out of the unknown state, break and move
148			* to the parsing for their appropriate status. --fl
149			*/
150			if(!IsUnknown(client_p))
151			break;
152			}
153			}
154
155			if (IsServer(client_p) \|\| IsConnecting(client_p) \|\| IsHandshake(client_p))
156			{
157			while (1)
158			{
159			if (IsDefunct(client_p))
160			return;
161			if ((dolen = extract_one_line(&lclient_p->buf_recvq,
162			readBuf)) == 0)
163			break;
164			client_dopacket(client_p, readBuf, dolen);
165			}
166			}
167	adx	163	else if (IsClient(client_p))
168	adx	30	{
169	michael	1219	if (ConfigFileEntry.no_oper_flood && (HasUMode(client_p, UMODE_OPER) \|\| IsCanFlood(client_p)))
170	adx	30	{
171			if (ConfigFileEntry.true_no_oper_flood)
172			checkflood = -1;
173			else
174			checkflood = 0;
175			}
176
177			/*
178			* Handle flood protection here - if we exceed our flood limit on
179			* messages in this loop, we simply drop out of the loop prematurely.
180			* -- adrian
181			*/
182	michael	2916	for (; ;)
183	adx	30	{
184			if (IsDefunct(client_p))
185	michael	2916	break;
186	adx	30
187			/* This flood protection works as follows:
188			*
189			* A client is given allow_read lines to send to the server. Every
190			* time a line is parsed, sent_parsed is increased. sent_parsed
191			* is decreased by 1 every time flood_recalc is called.
192			*
193			* Thus a client can 'burst' allow_read lines to the server, any
194			* excess lines will be parsed one per flood_recalc() call.
195			*
196			* Therefore a client will be penalised more if they keep flooding,
197			* as sent_parsed will always hover around the allow_read limit
198			* and no 'bursts' will be permitted.
199			*/
200			if (checkflood > 0)
201			{
202			if(lclient_p->sent_parsed >= lclient_p->allow_read)
203			break;
204			}
205	michael	2916
206	adx	30	/* allow opers 4 times the amount of messages as users. why 4?
207			* why not. :) --fl_
208			*/
209			else if (lclient_p->sent_parsed >= (4 * lclient_p->allow_read) &&
210			checkflood != -1)
211			break;
212
213			dolen = extract_one_line(&lclient_p->buf_recvq, readBuf);
214			if (dolen == 0)
215			break;
216
217			client_dopacket(client_p, readBuf, dolen);
218			lclient_p->sent_parsed++;
219			}
220			}
221			}
222
223			/* flood_endgrace()
224			*
225			* marks the end of the clients grace period
226			*/
227			void
228			flood_endgrace(struct Client *client_p)
229			{
230			SetFloodDone(client_p);
231
232			/* Drop their flood limit back down */
233			client_p->localClient->allow_read = MAX_FLOOD;
234
235			/* sent_parsed could be way over MAX_FLOOD but under MAX_FLOOD_BURST,
236			* so reset it.
237			*/
238			client_p->localClient->sent_parsed = 0;
239			}
240
241			/*
242			* flood_recalc
243			*
244			* recalculate the number of allowed flood lines. this should be called
245			* once a second on any given client. We then attempt to flush some data.
246			*/
247			void
248			flood_recalc(fde_t fd, void data)
249			{
250			struct Client *client_p = data;
251			struct LocalUser *lclient_p = client_p->localClient;
252	michael	2916
253	adx	30	/* allow a bursting client their allocation per second, allow
254			* a client whos flooding an extra 2 per second
255			*/
256			if (IsFloodDone(client_p))
257			lclient_p->sent_parsed -= 2;
258			else
259			lclient_p->sent_parsed = 0;
260	michael	2916
261	adx	30	if (lclient_p->sent_parsed < 0)
262			lclient_p->sent_parsed = 0;
263	michael	2916
264	adx	30	parse_client_queued(client_p);
265	michael	2916
266	adx	30	/* And now, try flushing .. */
267			if (!IsDead(client_p))
268			{
269			/* and finally, reset the flood check */
270			comm_setflush(fd, 1000, flood_recalc, client_p);
271			}
272			}
273
274			/*
275			* read_packet - Read a 'packet' of data from a connection and process it.
276			*/
277			void
278			read_packet(fde_t fd, void data)
279			{
280			struct Client *client_p = data;
281			int length = 0;
282
283			if (IsDefunct(client_p))
284			return;
285
286			/*
287			* Read some data. We used to do anti-flood protection here, but
288			* I personally think it makes the code too hairy to make sane.
289			* -- adrian
290			*/
291	michael	2916	do
292			{
293	adx	30	#ifdef HAVE_LIBCRYPTO
294			if (fd->ssl)
295			{
296			length = SSL_read(fd->ssl, readBuf, READBUF_SIZE);
297
298			/* translate openssl error codes, sigh */
299			if (length < 0)
300			switch (SSL_get_error(fd->ssl, length))
301	michael	2881	{
302	adx	30	case SSL_ERROR_WANT_WRITE:
303	michael	2881	comm_setselect(fd, COMM_SELECT_WRITE, (PF *)sendq_unblocked, client_p, 0);
304			return;
305			case SSL_ERROR_WANT_READ:
306			errno = EWOULDBLOCK;
307	adx	30	case SSL_ERROR_SYSCALL:
308	michael	2881	break;
309	michael	428	case SSL_ERROR_SSL:
310			if (errno == EAGAIN)
311			break;
312	adx	30	default:
313	michael	2881	length = errno = 0;
314			}
315	adx	30	}
316			else
317			#endif
318			{
319			length = recv(fd->fd, readBuf, READBUF_SIZE, 0);
320			}
321
322			if (length <= 0)
323			{
324			/*
325			* If true, then we can recover from this error. Just jump out of
326			* the loop and re-register a new io-request.
327			*/
328			if (length < 0 && ignoreErrno(errno))
329			break;
330
331			dead_link_on_read(client_p, length);
332			return;
333			}
334
335	michael	1798	dbuf_put(&client_p->localClient->buf_recvq, readBuf, length);
336	adx	30
337	michael	1241	if (client_p->localClient->lasttime < CurrentTime)
338			client_p->localClient->lasttime = CurrentTime;
339			if (client_p->localClient->lasttime > client_p->localClient->since)
340			client_p->localClient->since = CurrentTime;
341	adx	30	ClearPingSent(client_p);
342
343			/* Attempt to parse what we have */
344			parse_client_queued(client_p);
345
346			if (IsDefunct(client_p))
347			return;
348
349			/* Check to make sure we're not flooding */
350			if (!(IsServer(client_p) \|\| IsHandshake(client_p) \|\| IsConnecting(client_p))
351			&& (dbuf_length(&client_p->localClient->buf_recvq) >
352	michael	1632	get_recvq(&client_p->localClient->confs)))
353	adx	30	{
354	michael	1219	if (!(ConfigFileEntry.no_oper_flood && HasUMode(client_p, UMODE_OPER)))
355	adx	30	{
356			exit_client(client_p, client_p, "Excess Flood");
357			return;
358			}
359			}
360			}
361			#ifdef HAVE_LIBCRYPTO
362			while (length == sizeof(readBuf) \|\| fd->ssl);
363			#else
364			while (length == sizeof(readBuf));
365			#endif
366
367			/* If we get here, we need to register for another COMM_SELECT_READ */
368			comm_setselect(fd, COMM_SELECT_READ, read_packet, client_p, 0);
369			}
370
371			/*
372			* client_dopacket - copy packet to client buf and parse it
373			* client_p - pointer to client structure for which the buffer data
374			* applies.
375			* buffer - pointr to the buffer containing the newly read data
376			* length - number of valid bytes of data in the buffer
377			*
378			* Note:
379			* It is implicitly assumed that dopacket is called only
380			* with client_p of "local" variation, which contains all the
381			* necessary fields (buffer etc..)
382			*/
383			static void
384			client_dopacket(struct Client client_p, char buffer, size_t length)
385			{
386	michael	2916	/*
387	adx	30	* Update messages received
388			*/
389			++me.localClient->recv.messages;
390			++client_p->localClient->recv.messages;
391
392	michael	2916	/*
393	adx	30	* Update bytes received
394			*/
395			client_p->localClient->recv.bytes += length;
396			me.localClient->recv.bytes += length;
397
398			parse(client_p, buffer, buffer + length);
399			}