modules/m_list_safelist.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 #include "stdinc.h"
  35 #include "tools.h"
  36 #include "channel.h"
  37 #include "client.h"
  38 #include "hash.h"
  39 #include "irc_string.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 #include "event.h"
  49
  50 static 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: 26 $");
  79
  80 static int _modinit(void)
  81 {
  82         eventAdd("safelist_iterate_clients", safelist_iterate_clients, NULL, 3);
  83
  84         return 0;
  85 }
  86
  87 static void _moddeinit(void)
  88 {
  89         eventDelete(safelist_iterate_clients, NULL);
  90 }
  91
  92 static void safelist_check_cliexit(hook_data_client_exit * hdata)
  93 {
  94         /* Cancel the safelist request if we are disconnecting
  95          * from the server. That way it doesn't core. :P --nenolod
  96          */
  97         if (MyClient(hdata->target) && hdata->target->localClient->safelist_data != NULL)
  98         {
  99                 safelist_client_release(hdata->target);
 100         }
 101 }
 102
 103 /* m_list()
 104  *      parv[0] = sender prefix
 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                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 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) > CurrentTime))
 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 = CurrentTime;
 133         }
 134
 135         return mo_list(client_p, source_p, parc, parv);
 136 }
 137
 138 /* mo_list()
 139  *      parv[0] = sender prefix
 140  *      parv[1] = channel
 141  */
 142 static int mo_list(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 143 {
 144         struct ListClient params;
 145         char *p, *args;
 146         int i;
 147
 148         if (source_p->localClient->safelist_data != NULL)
 149         {
 150                 sendto_one_notice(source_p, ":/LIST aborted");
 151                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 152                 safelist_client_release(source_p);
 153                 return 0;
 154         }
 155
 156         /* XXX rather arbitrary -- jilles */
 157         params.users_min = 3;
 158         params.users_max = INT_MAX;
 159
 160         if (parc > 1 && parv[1] != NULL && !IsChannelName(parv[1]))
 161         {
 162                 args = LOCAL_COPY(parv[1]);
 163                 /* Make any specification cancel out defaults */
 164                 if (*args == '<')
 165                         params.users_min = 0;
 166
 167                 for (i = 0; i < 2; i++)
 168                 {
 169                         if ((p = strchr(args, ',')) != NULL)
 170                                 *p++ = '\0';
 171
 172                         if (*args == '<')
 173                         {
 174                                 args++;
 175                                 if (IsDigit(*args))
 176                                 {
 177                                         params.users_max = atoi(args);
 178                                         if (params.users_max == 0)
 179                                                 params.users_max = INT_MAX;
 180                                         else
 181                                                 params.users_max--;
 182                                 }
 183                                 else
 184                                         params.users_max = INT_MAX;
 185                         }
 186                         else if (*args == '>')
 187                         {
 188                                 args++;
 189                                 if (IsDigit(*args))
 190                                         params.users_min = atoi(args) + 1;
 191                                 else
 192                                         params.users_min = 0;
 193                         }
 194
 195                         if (EmptyString(p))
 196                                 break;
 197                         else
 198                                 args = p;
 199                 }
 200         }
 201         else if (parc > 1 && IsChannelName(parv[1]))
 202         {
 203                 safelist_channel_named(source_p, parv[1]);
 204                 return 0;
 205         }
 206
 207         safelist_client_instantiate(source_p, &params);
 208
 209         return 0;
 210 }
 211
 212 /*
 213  * safelist_sendq_exceeded()
 214  *
 215  * inputs       - pointer to client that needs checking
 216  * outputs      - 1 if a client has exceeded the reserved
 217  *                sendq limit, 0 if not
 218  * side effects - none
 219  *
 220  * When safelisting, we only use half of the SendQ at any
 221  * given time.
 222  */
 223 static int safelist_sendq_exceeded(struct Client *client_p)
 224 {
 225         if (linebuf_len(&client_p->localClient->buf_sendq) > (get_sendq(client_p) / 2))
 226                 return YES;
 227         else
 228                 return NO;
 229 }
 230
 231 /*
 232  * safelist_client_instantiate()
 233  *
 234  * inputs       - pointer to Client to be listed,
 235  *                struct ListClient to copy for params
 236  * outputs      - none
 237  * side effects - the safelist process begins for a
 238  *                client.
 239  *
 240  * Please do not ever call this on a non-local client.
 241  * If you do, you will get SIGSEGV.
 242  */
 243 static void safelist_client_instantiate(struct Client *client_p, struct ListClient *params)
 244 {
 245         struct ListClient *self;
 246
 247         s_assert(MyClient(client_p));
 248         s_assert(params != NULL);
 249
 250         self = MyMalloc(sizeof(struct ListClient));
 251
 252         self->hash_indice = 0;
 253         self->users_min = params->users_min;
 254         self->users_max = params->users_max;
 255
 256         client_p->localClient->safelist_data = self;
 257
 258         sendto_one(client_p, form_str(RPL_LISTSTART), me.name, client_p->name);
 259
 260         /* pop the client onto the queue for processing */
 261         dlinkAddAlloc(client_p, &safelisting_clients);
 262
 263         /* give the user some initial data to work with */
 264         safelist_iterate_client(client_p);
 265 }
 266
 267 /*
 268  * safelist_client_release()
 269  *
 270  * inputs       - pointer to Client being listed on
 271  * outputs      - none
 272  * side effects - the client is no longer being
 273  *                listed
 274  *
 275  * Please do not ever call this on a non-local client.
 276  * If you do, you will get SIGSEGV.
 277  */
 278 static void safelist_client_release(struct Client *client_p)
 279 {
 280         s_assert(MyClient(client_p));
 281
 282         dlinkFindDestroy(client_p, &safelisting_clients);
 283
 284         MyFree(client_p->localClient->safelist_data);
 285
 286         client_p->localClient->safelist_data = NULL;
 287
 288         sendto_one(client_p, form_str(RPL_LISTEND), me.name, client_p->name);
 289 }
 290
 291 /*
 292  * safelist_channel_named()
 293  *
 294  * inputs       - client pointer, channel name
 295  * outputs      - none
 296  * side effects - a named channel is listed
 297  */
 298 static void safelist_channel_named(struct Client *source_p, const char *name)
 299 {
 300         struct Channel *chptr;
 301         char *p;
 302         char *n = LOCAL_COPY(name);
 303
 304         sendto_one(source_p, form_str(RPL_LISTSTART), me.name, source_p->name);
 305
 306         if ((p = strchr(n, ',')))
 307                 *p = '\0';
 308
 309         if (*n == '\0')
 310         {
 311                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), name);
 312                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 313                 return;
 314         }
 315
 316         chptr = find_channel(n);
 317
 318         if (chptr == NULL)
 319         {
 320                 sendto_one_numeric(source_p, ERR_NOSUCHNICK, form_str(ERR_NOSUCHNICK), n);
 321                 sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 322                 return;
 323         }
 324
 325         if (ShowChannel(source_p, chptr))
 326                 sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 327                            dlink_list_length(&chptr->members),
 328                            chptr->topic == NULL ? "" : chptr->topic);
 329
 330         sendto_one(source_p, form_str(RPL_LISTEND), me.name, source_p->name);
 331         return;
 332 }
 333
 334 /*
 335  * safelist_one_channel()
 336  *
 337  * inputs       - client pointer and channel pointer
 338  * outputs      - none
 339  * side effects - a channel is listed if it meets the
 340  *                requirements
 341  */
 342 static void safelist_one_channel(struct Client *source_p, struct Channel *chptr)
 343 {
 344         struct ListClient *safelist_data = source_p->localClient->safelist_data;
 345
 346         if (SecretChannel(chptr) && !IsMember(source_p, chptr))
 347                 return;
 348
 349         if ((unsigned int)chptr->members.length < safelist_data->users_min
 350             || (unsigned int)chptr->members.length > safelist_data->users_max)
 351                 return;
 352
 353         sendto_one(source_p, form_str(RPL_LIST), me.name, source_p->name, chptr->chname,
 354                    chptr->members.length, chptr->topic == NULL ? "" : chptr->topic);
 355 }
 356
 357 /*
 358  * safelist_iterate_client()
 359  *
 360  * inputs       - client pointer
 361  * outputs      - none
 362  * side effects - the client's sendq is filled up again
 363  */
 364 static void safelist_iterate_client(struct Client *source_p)
 365 {
 366         dlink_node *ptr;
 367         int iter;
 368
 369         for (iter = source_p->localClient->safelist_data->hash_indice; iter < CH_MAX; iter++)
 370         {
 371                 if (safelist_sendq_exceeded(source_p->from) == YES)
 372                 {
 373                         source_p->localClient->safelist_data->hash_indice = iter;
 374                         return;
 375                 }
 376
 377                 DLINK_FOREACH(ptr, channelTable[iter].head)
 378                         safelist_one_channel(source_p, (struct Channel *) ptr->data);
 379         }
 380
 381         safelist_client_release(source_p);
 382 }
 383
 384 static void safelist_iterate_clients(void *unused)
 385 {
 386         dlink_node *n, *n2;
 387
 388         DLINK_FOREACH_SAFE(n, n2, safelisting_clients.head)
 389                 safelist_iterate_client((struct Client *)n->data);
 390 }