modules/m_list.c

   1 /*
   2  * charybdis: An advanced ircd.
   3  * m_list_safelist.c: Version of /list that uses the safelist code.
   4  *
   5  * Copyright (c) 2006 William Pitcock <nenolod@nenolod.net>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions are
   9  * met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright notice,
  12  *    this list of conditions and the following disclaimer.
  13  *
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * 3. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  24  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  25  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  26  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  27  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  29  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  30  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  31  * POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  * $Id: m_list.c 3372 2007-04-03 10:18:07Z nenolod $
  34  */
  35
  36 #include "stdinc.h"
  37 #include "tools.h"
  38 #include "channel.h"
  39 #include "client.h"
  40 #include "hash.h"
  41 #include "irc_string.h"
  42 #include "ircd.h"
  43 #include "numeric.h"
  44 #include "s_conf.h"
  45 #include "s_serv.h"
  46 #include "send.h"
  47 #include "msg.h"
  48 #include "parse.h"
  49 #include "modules.h"
  50 #include "event.h"
  51
  52 static rb_dlink_list safelisting_clients = { NULL, NULL, 0 };
  53
  54 static int _modinit(void);
  55 static void _moddeinit(void);
  56
  57 static int m_list(struct Client *, struct Client *, int, const char **);
  58 static int mo_list(struct Client *, struct Client *, int, const char **);
  59
  60 static void safelist_check_cliexit(hook_data_client_exit * hdata);
  61 static void safelist_client_instantiate(struct Client *, struct ListClient *);
  62 static void safelist_client_release(struct Client *);
  63 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr);
  64 static void safelist_iterate_client(struct Client *source_p);
  65 static void safelist_iterate_clients(void *unused);
  66 static void safelist_channel_named(struct Client *source_p, const char *name);
  67
  68 struct Message list_msgtab = {
  69         "LIST", 0, 0, 0, MFLG_SLOW,
  70         {mg_unreg, {m_list, 0}, mg_ignore, mg_ignore, mg_ignore, {mo_list, 0}}
  71 };
  72
  73 mapi_clist_av1 list_clist[] = { &list_msgtab, NULL };
  74
  75 mapi_hfn_list_av1 list_hfnlist[] = {
  76         {"client_exit", (hookfn) safelist_check_cliexit},
  77         {NULL, NULL}
  78 };
  79
  80 DECLARE_MODULE_AV1(list, _modinit, _moddeinit, list_clist, NULL, list_hfnlist, "$Revision: 3372 $");
  81
  82 static struct ev_entry *iterate_clients_ev = NULL;
  83
  84 static int _modinit(void)
  85 {
  86         iterate_clients_ev = rb_event_add("safelist_iterate_clients", safelist_iterate_clients, NULL, 3);
  87
  88         return 0;
  89 }
  90
  91 static void _moddeinit(void)
  92 {
  93         rb_event_delete(iterate_clients_ev);
  94 }
  95
  96 static void safelist_check_cliexit(hook_data_client_exit * hdata)
  97 {
  98         /* Cancel the safelist request if we are disconnecting
  99          * from the server. That way it doesn't core. :P --nenolod
 100          */
 101         if (MyClient(hdata->target) && hdata->target->localClient->safelist_data != NULL)
 102         {
 103                 safelist_client_release(hdata->target);
 104         }
 105 }
 106
 107 /* m_list()
 108  *      parv[0] = sender prefix
 109  *      parv[1] = channel
 110  *
 111  * XXX - With SAFELIST, do we really need to continue pacing?
 112  *       In theory, the server cannot be lagged by this. --nenolod
 113  */
 114 static int m_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 115 {
 116         static time_t last_used = 0L;
 117
 118         if (source_p->localClient->safelist_data != NULL)
 119         {
 120                 sendto_one_notice(source_p, ":/LIST aborted");
 121                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 122                 safelist_client_release(source_p);
 123                 return 0;
 124         }
 125
 126         if (parc < 2 || !IsChannelName(parv[1]))
 127         {
 128                 /* pace this due to the sheer traffic involved */
 129                 if (((last_used + ConfigFileEntry.pace_wait) > CurrentTime))
 130                 {
 131                         sendto_one(source_p, form_str(RPL_LOAD2HI), me.name, source_p->name, "LIST");
 132                         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 133                         return 0;
 134                 }
 135                 else
 136                         last_used = CurrentTime;
 137         }
 138
 139         return mo_list(client_p, source_p, parc, parv);
 140 }
 141
 142 /* mo_list()
 143  *      parv[0] = sender prefix
 144  *      parv[1] = channel
 145  */
 146 static int mo_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 147 {
 148         struct ListClient params;
 149         char *p, *args;
 150         int i;
 151
 152         if (source_p->localClient->safelist_data != NULL)
 153         {
 154                 sendto_one_notice(source_p, ":/LIST aborted");
 155                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 156                 safelist_client_release(source_p);
 157                 return 0;
 158         }
 159
 160         /* XXX rather arbitrary -- jilles */
 161         params.users_min = 3;
 162         params.users_max = INT_MAX;
 163
 164         if (parc > 1 && parv[1] != NULL && !IsChannelName(parv[1]))
 165         {
 166                 args = LOCAL_COPY(parv[1]);
 167                 /* Make any specification cancel out defaults */
 168                 if (*args == '<')
 169                         params.users_min = 0;
 170
 171                 for (i = 0; i < 2; i++)
 172                 {
 173                         if ((p = strchr(args, ',')) != NULL)
 174                                 *p++ = '\0';
 175
 176                         if (*args == '<')
 177                         {
 178                                 args++;
 179                                 if (IsDigit(*args))
 180                                 {
 181                                         params.users_max = atoi(args);
 182                                         if (params.users_max == 0)
 183                                                 params.users_max = INT_MAX;
 184                                         else
 185                                                 params.users_max--;
 186                                 }
 187                                 else
 188                                         params.users_max = INT_MAX;
 189                         }
 190                         else if (*args == '>')
 191                         {
 192                                 args++;
 193                                 if (IsDigit(*args))
 194                                         params.users_min = atoi(args) + 1;
 195                                 else
 196                                         params.users_min = 0;
 197                         }
 198
 199                         if (EmptyString(p))
 200                                 break;
 201                         else
 202                                 args = p;
 203                 }
 204         }
 205         else if (parc > 1 && IsChannelName(parv[1]))
 206         {
 207                 safelist_channel_named(source_p, parv[1]);
 208                 return 0;
 209         }
 210
 211         safelist_client_instantiate(source_p, &params);
 212
 213         return 0;
 214 }
 215
 216 /*
 217  * safelist_sendq_exceeded()
 218  *
 219  * inputs       - pointer to client that needs checking
 220  * outputs      - 1 if a client has exceeded the reserved
 221  *                sendq limit, 0 if not
 222  * side effects - none
 223  *
 224  * When safelisting, we only use half of the SendQ at any
 225  * given time.
 226  */
 227 static int safelist_sendq_exceeded(struct Client *client_p)
 228 {
 229         if (rb_linebuf_len(&client_p->localClient->buf_sendq) > (get_sendq(client_p) / 2))
 230                 return YES;
 231         else
 232                 return NO;
 233 }
 234
 235 /*
 236  * safelist_client_instantiate()
 237  *
 238  * inputs       - pointer to Client to be listed,
 239  *                struct ListClient to copy for params
 240  * outputs      - none
 241  * side effects - the safelist process begins for a
 242  *                client.
 243  *
 244  * Please do not ever call this on a non-local client.
 245  * If you do, you will get SIGSEGV.
 246  */
 247 static void safelist_client_instantiate(struct Client *client_p, struct ListClient *params)
 248 {
 249         struct ListClient *self;
 250
 251         s_assert(MyClient(client_p));
 252         s_assert(params != NULL);
 253
 254         self = MyMalloc(sizeof(struct ListClient));
 255
 256         self->hash_indice = 0;
 257         self->users_min = params->users_min;
 258         self->users_max = params->users_max;
 259
 260         client_p->localClient->safelist_data = self;
 261
 262         sendto_one(client_p, form_str(RPL_LISTSTART), me.name, client_p->name);
 263
 264         /* pop the client onto the queue for processing */
 265         rb_dlinkAddAlloc(client_p, &safelisting_clients);
 266
 267         /* give the user some initial data to work with */
 268         safelist_iterate_client(client_p);
 269 }
 270
 271 /*
 272  * safelist_client_release()
 273  *
 274  * inputs       - pointer to Client being listed on
 275  * outputs      - none
 276  * side effects - the client is no longer being
 277  *                listed
 278  *
 279  * Please do not ever call this on a non-local client.
 280  * If you do, you will get SIGSEGV.
 281  */
 282 static void safelist_client_release(struct Client *client_p)
 283 {
 284         s_assert(MyClient(client_p));
 285
 286         rb_dlinkFindDestroy(client_p, &safelisting_clients);
 287
 288         MyFree(client_p->localClient->safelist_data);
 289
 290         client_p->localClient->safelist_data = NULL;
 291
 292         sendto_one(client_p, form_str(RPL_LISTEND), me.name, client_p->name);
 293 }
 294
 295 /*
 296  * safelist_channel_named()
 297  *
 298  * inputs       - client pointer, channel name
 299  * outputs      - none
 300  * side effects - a named channel is listed
 301  */
 302 static void safelist_channel_named(struct Client *source_p, const char *name)
 303 {
 304         struct Channel *chptr;
 305         char *p;
 306         char *n = LOCAL_COPY(name);
 307
 308         sendto_one(source_p, form_str(RPL_LISTSTART), me.name, source_p->name);
 309
 310         if ((p = strchr(n, ',')))
 311                 *p = '\0';
 312
 313         if (*n == '\0')
 314         {
 315                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), name);
 316                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 317                 return;
 318         }
 319
 320         chptr = find_channel(n);
 321
 322         if (chptr == NULL)
 323         {
 324                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), n);
 325                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 326                 return;
 327         }
 328
 329         if (ShowChannel(source_p, chptr))
 330                 sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 331                            rb_dlink_list_length(&chptr->members),
 332                            chptr->topic == NULL ? "" : chptr->topic);
 333
 334         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 335         return;
 336 }
 337
 338 /*
 339  * safelist_one_channel()
 340  *
 341  * inputs       - client pointer and channel pointer
 342  * outputs      - none
 343  * side effects - a channel is listed if it meets the
 344  *                requirements
 345  */
 346 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr)
 347 {
 348         struct ListClient *safelist_data = source_p->localClient->safelist_data;
 349
 350         if (SecretChannel(chptr) && !IsMember(source_p, chptr))
 351                 return;
 352
 353         if ((unsigned int)chptr->members.length < safelist_data->users_min
 354             || (unsigned int)chptr->members.length > safelist_data->users_max)
 355                 return;
 356
 357         sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 358                    chptr->members.length, chptr->topic == NULL ? "" : chptr->topic);
 359 }
 360
 361 /*
 362  * safelist_iterate_client()
 363  *
 364  * inputs       - client pointer
 365  * outputs      - none
 366  * side effects - the client's sendq is filled up again
 367  */
 368 static void safelist_iterate_client(struct Client *source_p)
 369 {
 370         rb_dlink_node *ptr;
 371         int iter;
 372
 373         for (iter = source_p->localClient->safelist_data->hash_indice; iter < CH_MAX; iter++)
 374         {
 375                 if (safelist_sendq_exceeded(source_p->from) == YES)
 376                 {
 377                         source_p->localClient->safelist_data->hash_indice = iter;
 378                         return;
 379                 }
 380
 381                 RB_DLINK_FOREACH(ptr, channelTable[iter].head)
 382                         safelist_one_channel(source_p, (struct Channel *) ptr->data);
 383         }
 384
 385         safelist_client_release(source_p);
 386 }
 387
 388 static void safelist_iterate_clients(void *unused)
 389 {
 390         rb_dlink_node *n, *n2;
 391
 392         RB_DLINK_FOREACH_SAFE(n, n2, safelisting_clients.head)
 393                 safelist_iterate_client((struct Client *)n->data);
 394 }