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  */
  34
  35 #include "stdinc.h"
  36 #include "channel.h"
  37 #include "client.h"
  38 #include "hash.h"
  39 #include "match.h"
  40 #include "ircd.h"
  41 #include "numeric.h"
  42 #include "s_conf.h"
  43 #include "s_serv.h"
  44 #include "send.h"
  45 #include "msg.h"
  46 #include "parse.h"
  47 #include "modules.h"
  48
  49 static rb_dlink_list safelisting_clients = { NULL, NULL, 0 };
  50
  51 static int _modinit(void);
  52 static void _moddeinit(void);
  53
  54 static int m_list(struct Client *, struct Client *, int, const char **);
  55 static int mo_list(struct Client *, struct Client *, int, const char **);
  56
  57 static void safelist_check_cliexit(hook_data_client_exit * hdata);
  58 static void safelist_client_instantiate(struct Client *, struct ListClient *);
  59 static void safelist_client_release(struct Client *);
  60 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr);
  61 static void safelist_iterate_client(struct Client *source_p);
  62 static void safelist_iterate_clients(void *unused);
  63 static void safelist_channel_named(struct Client *source_p, const char *name);
  64
  65 struct Message list_msgtab = {
  66         "LIST", 0, 0, 0, MFLG_SLOW,
  67         {mg_unreg, {m_list, 0}, mg_ignore, mg_ignore, mg_ignore, {mo_list, 0}}
  68 };
  69
  70 mapi_clist_av1 list_clist[] = { &list_msgtab, NULL };
  71
  72 mapi_hfn_list_av1 list_hfnlist[] = {
  73         {"client_exit", (hookfn) safelist_check_cliexit},
  74         {NULL, NULL}
  75 };
  76
  77 DECLARE_MODULE_AV1(list, _modinit, _moddeinit, list_clist, NULL, list_hfnlist, "$Revision: 3372 $");
  78
  79 static struct ev_entry *iterate_clients_ev = NULL;
  80
  81 static int _modinit(void)
  82 {
  83         iterate_clients_ev = rb_event_add("safelist_iterate_clients", safelist_iterate_clients, NULL, 3);
  84
  85         return 0;
  86 }
  87
  88 static void _moddeinit(void)
  89 {
  90         rb_event_delete(iterate_clients_ev);
  91 }
  92
  93 static void safelist_check_cliexit(hook_data_client_exit * hdata)
  94 {
  95         /* Cancel the safelist request if we are disconnecting
  96          * from the server. That way it doesn't core. :P --nenolod
  97          */
  98         if (MyClient(hdata->target) && hdata->target->localClient->safelist_data != NULL)
  99         {
 100                 safelist_client_release(hdata->target);
 101         }
 102 }
 103
 104 /* m_list()
 105  *      parv[1] = channel
 106  *
 107  * XXX - With SAFELIST, do we really need to continue pacing?
 108  *       In theory, the server cannot be lagged by this. --nenolod
 109  */
 110 static int m_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 111 {
 112         static time_t last_used = 0L;
 113
 114         if (source_p->localClient->safelist_data != NULL)
 115         {
 116                 sendto_one_notice(source_p, ":/LIST aborted");
 117                 safelist_client_release(source_p);
 118                 return 0;
 119         }
 120
 121         if (parc < 2 || !IsChannelName(parv[1]))
 122         {
 123                 /* pace this due to the sheer traffic involved */
 124                 if (((last_used + ConfigFileEntry.pace_wait) > rb_current_time()))
 125                 {
 126                         sendto_one(source_p, form_str(RPL_LOAD2HI), me.name, source_p->name, "LIST");
 127                         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 128                         return 0;
 129                 }
 130                 else
 131                         last_used = rb_current_time();
 132         }
 133
 134         return mo_list(client_p, source_p, parc, parv);
 135 }
 136
 137 /* mo_list()
 138  *      parv[1] = channel
 139  */
 140 static int mo_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 141 {
 142         struct ListClient params;
 143         char *p, *args;
 144         int i;
 145
 146         if (source_p->localClient->safelist_data != NULL)
 147         {
 148                 sendto_one_notice(source_p, ":/LIST aborted");
 149                 safelist_client_release(source_p);
 150                 return 0;
 151         }
 152
 153         /* Let the user set it */
 154         params.users_min = ConfigFileEntry.hide_channel_below_users;
 155         params.users_max = INT_MAX;
 156
 157         if (parc > 1 && parv[1] != NULL && !IsChannelName(parv[1]))
 158         {
 159                 args = LOCAL_COPY(parv[1]);
 160                 /* Make any specification cancel out defaults */
 161                 if (*args == '<')
 162                         params.users_min = 0;
 163
 164                 for (i = 0; i < 2; i++)
 165                 {
 166                         if ((p = strchr(args, ',')) != NULL)
 167                                 *p++ = '\0';
 168
 169                         if (*args == '<')
 170                         {
 171                                 args++;
 172                                 if (IsDigit(*args))
 173                                 {
 174                                         params.users_max = atoi(args);
 175                                         if (params.users_max == 0)
 176                                                 params.users_max = INT_MAX;
 177                                         else
 178                                                 params.users_max--;
 179                                 }
 180                                 else
 181                                         params.users_max = INT_MAX;
 182                         }
 183                         else if (*args == '>')
 184                         {
 185                                 args++;
 186                                 if (IsDigit(*args))
 187                                         params.users_min = atoi(args) + 1;
 188                                 else
 189                                         params.users_min = 0;
 190                         }
 191
 192                         if (EmptyString(p))
 193                                 break;
 194                         else
 195                                 args = p;
 196                 }
 197         }
 198         else if (parc > 1 && IsChannelName(parv[1]))
 199         {
 200                 safelist_channel_named(source_p, parv[1]);
 201                 return 0;
 202         }
 203
 204         safelist_client_instantiate(source_p, &params);
 205
 206         return 0;
 207 }
 208
 209 /*
 210  * safelist_sendq_exceeded()
 211  *
 212  * inputs       - pointer to client that needs checking
 213  * outputs      - 1 if a client has exceeded the reserved
 214  *                sendq limit, 0 if not
 215  * side effects - none
 216  *
 217  * When safelisting, we only use half of the SendQ at any
 218  * given time.
 219  */
 220 static int safelist_sendq_exceeded(struct Client *client_p)
 221 {
 222         if (rb_linebuf_len(&client_p->localClient->buf_sendq) > (get_sendq(client_p) / 2))
 223                 return YES;
 224         else
 225                 return NO;
 226 }
 227
 228 /*
 229  * safelist_client_instantiate()
 230  *
 231  * inputs       - pointer to Client to be listed,
 232  *                struct ListClient to copy for params
 233  * outputs      - none
 234  * side effects - the safelist process begins for a
 235  *                client.
 236  *
 237  * Please do not ever call this on a non-local client.
 238  * If you do, you will get SIGSEGV.
 239  */
 240 static void safelist_client_instantiate(struct Client *client_p, struct ListClient *params)
 241 {
 242         struct ListClient *self;
 243
 244         s_assert(MyClient(client_p));
 245         s_assert(params != NULL);
 246
 247         self = rb_malloc(sizeof(struct ListClient));
 248
 249         self->hash_indice = 0;
 250         self->users_min = params->users_min;
 251         self->users_max = params->users_max;
 252
 253         client_p->localClient->safelist_data = self;
 254
 255         sendto_one(client_p, form_str(RPL_LISTSTART), me.name, client_p->name);
 256
 257         /* pop the client onto the queue for processing */
 258         rb_dlinkAddAlloc(client_p, &safelisting_clients);
 259
 260         /* give the user some initial data to work with */
 261         safelist_iterate_client(client_p);
 262 }
 263
 264 /*
 265  * safelist_client_release()
 266  *
 267  * inputs       - pointer to Client being listed on
 268  * outputs      - none
 269  * side effects - the client is no longer being
 270  *                listed
 271  *
 272  * Please do not ever call this on a non-local client.
 273  * If you do, you will get SIGSEGV.
 274  */
 275 static void safelist_client_release(struct Client *client_p)
 276 {
 277         s_assert(MyClient(client_p));
 278
 279         rb_dlinkFindDestroy(client_p, &safelisting_clients);
 280
 281         rb_free(client_p->localClient->safelist_data);
 282
 283         client_p->localClient->safelist_data = NULL;
 284
 285         sendto_one(client_p, form_str(RPL_LISTEND), me.name, client_p->name);
 286 }
 287
 288 /*
 289  * safelist_channel_named()
 290  *
 291  * inputs       - client pointer, channel name
 292  * outputs      - none
 293  * side effects - a named channel is listed
 294  */
 295 static void safelist_channel_named(struct Client *source_p, const char *name)
 296 {
 297         struct Channel *chptr;
 298         char *p;
 299         char *n = LOCAL_COPY(name);
 300
 301         sendto_one(source_p, form_str(RPL_LISTSTART), me.name, source_p->name);
 302
 303         if ((p = strchr(n, ',')))
 304                 *p = '\0';
 305
 306         if (*n == '\0')
 307         {
 308                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), name);
 309                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 310                 return;
 311         }
 312
 313         chptr = find_channel(n);
 314
 315         if (chptr == NULL)
 316         {
 317                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), n);
 318                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 319                 return;
 320         }
 321
 322         if (!SecretChannel(chptr) || IsMember(source_p, chptr))
 323                 sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 324                            rb_dlink_list_length(&chptr->members),
 325                            chptr->topic == NULL ? "" : chptr->topic);
 326
 327         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 328         return;
 329 }
 330
 331 /*
 332  * safelist_one_channel()
 333  *
 334  * inputs       - client pointer and channel pointer
 335  * outputs      - none
 336  * side effects - a channel is listed if it meets the
 337  *                requirements
 338  */
 339 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr)
 340 {
 341         struct ListClient *safelist_data = source_p->localClient->safelist_data;
 342
 343         if (SecretChannel(chptr) && !IsMember(source_p, chptr))
 344                 return;
 345
 346         if ((unsigned int)chptr->members.length < safelist_data->users_min
 347             || (unsigned int)chptr->members.length > safelist_data->users_max)
 348                 return;
 349
 350         sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 351                    chptr->members.length, chptr->topic == NULL ? "" : chptr->topic);
 352 }
 353
 354 /*
 355  * safelist_iterate_client()
 356  *
 357  * inputs       - client pointer
 358  * outputs      - none
 359  * side effects - the client's sendq is filled up again
 360  */
 361 static void safelist_iterate_client(struct Client *source_p)
 362 {
 363         rb_dlink_node *ptr;
 364         int iter;
 365
 366         for (iter = source_p->localClient->safelist_data->hash_indice; iter < CH_MAX; iter++)
 367         {
 368                 if (safelist_sendq_exceeded(source_p->from) == YES)
 369                 {
 370                         source_p->localClient->safelist_data->hash_indice = iter;
 371                         return;
 372                 }
 373
 374                 RB_DLINK_FOREACH(ptr, channelTable[iter].head)
 375                         safelist_one_channel(source_p, (struct Channel *) ptr->data);
 376         }
 377
 378         safelist_client_release(source_p);
 379 }
 380
 381 static void safelist_iterate_clients(void *unused)
 382 {
 383         rb_dlink_node *n, *n2;
 384
 385         RB_DLINK_FOREACH_SAFE(n, n2, safelisting_clients.head)
 386                 safelist_iterate_client((struct Client *)n->data);
 387 }