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 "channel.h"
  38 #include "client.h"
  39 #include "hash.h"
  40 #include "match.h"
  41 #include "ircd.h"
  42 #include "numeric.h"
  43 #include "s_conf.h"
  44 #include "s_serv.h"
  45 #include "send.h"
  46 #include "msg.h"
  47 #include "parse.h"
  48 #include "modules.h"
  49
  50 static rb_dlink_list safelisting_clients = { NULL, NULL, 0 };
  51
  52 static int _modinit(void);
  53 static void _moddeinit(void);
  54
  55 static int m_list(struct Client *, struct Client *, int, const char **);
  56 static int mo_list(struct Client *, struct Client *, int, const char **);
  57
  58 static void safelist_check_cliexit(hook_data_client_exit * hdata);
  59 static void safelist_client_instantiate(struct Client *, struct ListClient *);
  60 static void safelist_client_release(struct Client *);
  61 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr);
  62 static void safelist_iterate_client(struct Client *source_p);
  63 static void safelist_iterate_clients(void *unused);
  64 static void safelist_channel_named(struct Client *source_p, const char *name);
  65
  66 struct Message list_msgtab = {
  67         "LIST", 0, 0, 0, MFLG_SLOW,
  68         {mg_unreg, {m_list, 0}, mg_ignore, mg_ignore, mg_ignore, {mo_list, 0}}
  69 };
  70
  71 mapi_clist_av1 list_clist[] = { &list_msgtab, NULL };
  72
  73 mapi_hfn_list_av1 list_hfnlist[] = {
  74         {"client_exit", (hookfn) safelist_check_cliexit},
  75         {NULL, NULL}
  76 };
  77
  78 DECLARE_MODULE_AV1(list, _modinit, _moddeinit, list_clist, NULL, list_hfnlist, "$Revision: 3372 $");
  79
  80 static struct ev_entry *iterate_clients_ev = NULL;
  81
  82 static int _modinit(void)
  83 {
  84         iterate_clients_ev = rb_event_add("safelist_iterate_clients", safelist_iterate_clients, NULL, 3);
  85
  86         return 0;
  87 }
  88
  89 static void _moddeinit(void)
  90 {
  91         rb_event_delete(iterate_clients_ev);
  92 }
  93
  94 static void safelist_check_cliexit(hook_data_client_exit * hdata)
  95 {
  96         /* Cancel the safelist request if we are disconnecting
  97          * from the server. That way it doesn't core. :P --nenolod
  98          */
  99         if (MyClient(hdata->target) && hdata->target->localClient->safelist_data != NULL)
 100         {
 101                 safelist_client_release(hdata->target);
 102         }
 103 }
 104
 105 /* m_list()
 106  *      parv[1] = channel
 107  *
 108  * XXX - With SAFELIST, do we really need to continue pacing?
 109  *       In theory, the server cannot be lagged by this. --nenolod
 110  */
 111 static int m_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 112 {
 113         static time_t last_used = 0L;
 114
 115         if (source_p->localClient->safelist_data != NULL)
 116         {
 117                 sendto_one_notice(source_p, ":/LIST aborted");
 118                 safelist_client_release(source_p);
 119                 return 0;
 120         }
 121
 122         if (parc < 2 || !IsChannelName(parv[1]))
 123         {
 124                 /* pace this due to the sheer traffic involved */
 125                 if (((last_used + ConfigFileEntry.pace_wait) > rb_current_time()))
 126                 {
 127                         sendto_one(source_p, form_str(RPL_LOAD2HI), me.name, source_p->name, "LIST");
 128                         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 129                         return 0;
 130                 }
 131                 else
 132                         last_used = rb_current_time();
 133         }
 134
 135         return mo_list(client_p, source_p, parc, parv);
 136 }
 137
 138 /* mo_list()
 139  *      parv[1] = channel
 140  */
 141 static int mo_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 142 {
 143         struct ListClient params;
 144         char *p, *args;
 145         int i;
 146
 147         if (source_p->localClient->safelist_data != NULL)
 148         {
 149                 sendto_one_notice(source_p, ":/LIST aborted");
 150                 safelist_client_release(source_p);
 151                 return 0;
 152         }
 153
 154         /* XXX rather arbitrary -- jilles */
 155         params.users_min = 3;
 156         params.users_max = INT_MAX;
 157
 158         if (parc > 1 && parv[1] != NULL && !IsChannelName(parv[1]))
 159         {
 160                 args = LOCAL_COPY(parv[1]);
 161                 /* Make any specification cancel out defaults */
 162                 if (*args == '<')
 163                         params.users_min = 0;
 164
 165                 for (i = 0; i < 2; i++)
 166                 {
 167                         if ((p = strchr(args, ',')) != NULL)
 168                                 *p++ = '\0';
 169
 170                         if (*args == '<')
 171                         {
 172                                 args++;
 173                                 if (IsDigit(*args))
 174                                 {
 175                                         params.users_max = atoi(args);
 176                                         if (params.users_max == 0)
 177                                                 params.users_max = INT_MAX;
 178                                         else
 179                                                 params.users_max--;
 180                                 }
 181                                 else
 182                                         params.users_max = INT_MAX;
 183                         }
 184                         else if (*args == '>')
 185                         {
 186                                 args++;
 187                                 if (IsDigit(*args))
 188                                         params.users_min = atoi(args) + 1;
 189                                 else
 190                                         params.users_min = 0;
 191                         }
 192
 193                         if (EmptyString(p))
 194                                 break;
 195                         else
 196                                 args = p;
 197                 }
 198         }
 199         else if (parc > 1 && IsChannelName(parv[1]))
 200         {
 201                 safelist_channel_named(source_p, parv[1]);
 202                 return 0;
 203         }
 204
 205         safelist_client_instantiate(source_p, &params);
 206
 207         return 0;
 208 }
 209
 210 /*
 211  * safelist_sendq_exceeded()
 212  *
 213  * inputs       - pointer to client that needs checking
 214  * outputs      - 1 if a client has exceeded the reserved
 215  *                sendq limit, 0 if not
 216  * side effects - none
 217  *
 218  * When safelisting, we only use half of the SendQ at any
 219  * given time.
 220  */
 221 static int safelist_sendq_exceeded(struct Client *client_p)
 222 {
 223         if (rb_linebuf_len(&client_p->localClient->buf_sendq) > (get_sendq(client_p) / 2))
 224                 return YES;
 225         else
 226                 return NO;
 227 }
 228
 229 /*
 230  * safelist_client_instantiate()
 231  *
 232  * inputs       - pointer to Client to be listed,
 233  *                struct ListClient to copy for params
 234  * outputs      - none
 235  * side effects - the safelist process begins for a
 236  *                client.
 237  *
 238  * Please do not ever call this on a non-local client.
 239  * If you do, you will get SIGSEGV.
 240  */
 241 static void safelist_client_instantiate(struct Client *client_p, struct ListClient *params)
 242 {
 243         struct ListClient *self;
 244
 245         s_assert(MyClient(client_p));
 246         s_assert(params != NULL);
 247
 248         self = rb_malloc(sizeof(struct ListClient));
 249
 250         self->hash_indice = 0;
 251         self->users_min = params->users_min;
 252         self->users_max = params->users_max;
 253
 254         client_p->localClient->safelist_data = self;
 255
 256         sendto_one(client_p, form_str(RPL_LISTSTART), me.name, client_p->name);
 257
 258         /* pop the client onto the queue for processing */
 259         rb_dlinkAddAlloc(client_p, &safelisting_clients);
 260
 261         /* give the user some initial data to work with */
 262         safelist_iterate_client(client_p);
 263 }
 264
 265 /*
 266  * safelist_client_release()
 267  *
 268  * inputs       - pointer to Client being listed on
 269  * outputs      - none
 270  * side effects - the client is no longer being
 271  *                listed
 272  *
 273  * Please do not ever call this on a non-local client.
 274  * If you do, you will get SIGSEGV.
 275  */
 276 static void safelist_client_release(struct Client *client_p)
 277 {
 278         s_assert(MyClient(client_p));
 279
 280         rb_dlinkFindDestroy(client_p, &safelisting_clients);
 281
 282         rb_free(client_p->localClient->safelist_data);
 283
 284         client_p->localClient->safelist_data = NULL;
 285
 286         sendto_one(client_p, form_str(RPL_LISTEND), me.name, client_p->name);
 287 }
 288
 289 /*
 290  * safelist_channel_named()
 291  *
 292  * inputs       - client pointer, channel name
 293  * outputs      - none
 294  * side effects - a named channel is listed
 295  */
 296 static void safelist_channel_named(struct Client *source_p, const char *name)
 297 {
 298         struct Channel *chptr;
 299         char *p;
 300         char *n = LOCAL_COPY(name);
 301
 302         sendto_one(source_p, form_str(RPL_LISTSTART), me.name, source_p->name);
 303
 304         if ((p = strchr(n, ',')))
 305                 *p = '\0';
 306
 307         if (*n == '\0')
 308         {
 309                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), name);
 310                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 311                 return;
 312         }
 313
 314         chptr = find_channel(n);
 315
 316         if (chptr == NULL)
 317         {
 318                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), n);
 319                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 320                 return;
 321         }
 322
 323         if (!SecretChannel(chptr) || IsMember(source_p, chptr))
 324                 sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 325                            rb_dlink_list_length(&chptr->members),
 326                            chptr->topic == NULL ? "" : chptr->topic);
 327
 328         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 329         return;
 330 }
 331
 332 /*
 333  * safelist_one_channel()
 334  *
 335  * inputs       - client pointer and channel pointer
 336  * outputs      - none
 337  * side effects - a channel is listed if it meets the
 338  *                requirements
 339  */
 340 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr)
 341 {
 342         struct ListClient *safelist_data = source_p->localClient->safelist_data;
 343
 344         if (SecretChannel(chptr) && !IsMember(source_p, chptr))
 345                 return;
 346
 347         if ((unsigned int)chptr->members.length < safelist_data->users_min
 348             || (unsigned int)chptr->members.length > safelist_data->users_max)
 349                 return;
 350
 351         sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 352                    chptr->members.length, chptr->topic == NULL ? "" : chptr->topic);
 353 }
 354
 355 /*
 356  * safelist_iterate_client()
 357  *
 358  * inputs       - client pointer
 359  * outputs      - none
 360  * side effects - the client's sendq is filled up again
 361  */
 362 static void safelist_iterate_client(struct Client *source_p)
 363 {
 364         rb_dlink_node *ptr;
 365         int iter;
 366
 367         for (iter = source_p->localClient->safelist_data->hash_indice; iter < CH_MAX; iter++)
 368         {
 369                 if (safelist_sendq_exceeded(source_p->from) == YES)
 370                 {
 371                         source_p->localClient->safelist_data->hash_indice = iter;
 372                         return;
 373                 }
 374
 375                 RB_DLINK_FOREACH(ptr, channelTable[iter].head)
 376                         safelist_one_channel(source_p, (struct Channel *) ptr->data);
 377         }
 378
 379         safelist_client_release(source_p);
 380 }
 381
 382 static void safelist_iterate_clients(void *unused)
 383 {
 384         rb_dlink_node *n, *n2;
 385
 386         RB_DLINK_FOREACH_SAFE(n, n2, safelisting_clients.head)
 387                 safelist_iterate_client((struct Client *)n->data);
 388 }