modules/m_cap.c

   1 /* modules/m_cap.c
   2  *
   3  *  Copyright (C) 2005 Lee Hardy <lee@leeh.co.uk>
   4  *  Copyright (C) 2005 ircd-ratbox development team
   5  *  Copyright (C) 2016 William Pitcock <nenolod@dereferenced.org>
   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  * 2.Redistributions in binary form must reproduce the above copyright
  14  *   notice, this list of conditions and the following disclaimer in the
  15  *   documentation and/or other materials provided with the distribution.
  16  * 3.The name of the author may not be used to endorse or promote products
  17  *   derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  28  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include "stdinc.h"
  33 #include "class.h"
  34 #include "client.h"
  35 #include "match.h"
  36 #include "ircd.h"
  37 #include "numeric.h"
  38 #include "msg.h"
  39 #include "parse.h"
  40 #include "modules.h"
  41 #include "s_serv.h"
  42 #include "s_user.h"
  43 #include "send.h"
  44 #include "s_conf.h"
  45 #include "hash.h"
  46
  47 typedef int (*bqcmp)(const void *, const void *);
  48
  49 static int m_cap(struct MsgBuf *, struct Client *, struct Client *, int, const char **);
  50
  51 struct Message cap_msgtab = {
  52         "CAP", 0, 0, 0, 0,
  53         {{m_cap, 2}, {m_cap, 2}, mg_ignore, mg_ignore, mg_ignore, {m_cap, 2}}
  54 };
  55
  56 mapi_clist_av1 cap_clist[] = { &cap_msgtab, NULL };
  57 DECLARE_MODULE_AV2(cap, NULL, NULL, cap_clist, NULL, NULL, NULL, NULL, NULL);
  58
  59 #define IsCapableEntry(c, e)            IsCapable(c, 1 << (e)->value)
  60 #define HasCapabilityFlag(c, f)         (c->ownerdata != NULL && (((struct ClientCapability *)c->ownerdata)->flags & (f)) == f)
  61
  62 static inline int
  63 clicap_visible(struct Client *client_p, const struct CapabilityEntry *cap)
  64 {
  65         struct ClientCapability *clicap;
  66
  67         /* orphaned caps shouldn't be visible */
  68         if (cap->flags & CAP_ORPHANED)
  69                 return 0;
  70
  71         if (cap->ownerdata == NULL)
  72                 return 1;
  73
  74         clicap = cap->ownerdata;
  75         if (clicap->visible == NULL)
  76                 return 1;
  77
  78         return clicap->visible(client_p);
  79 }
  80
  81 /* clicap_find()
  82  *   Used iteratively over a buffer, extracts individual cap tokens.
  83  *
  84  * Inputs: buffer to start iterating over (NULL to iterate over existing buf)
  85  *         int pointer to whether the cap token is negated
  86  *         int pointer to whether we finish with success
  87  * Ouputs: Cap entry if found, NULL otherwise.
  88  */
  89 static struct CapabilityEntry *
  90 clicap_find(const char *data, int *negate, int *finished)
  91 {
  92         static char buf[BUFSIZE];
  93         static char *p;
  94         struct CapabilityEntry *cap;
  95         char *s;
  96
  97         *negate = 0;
  98
  99         if(data)
 100         {
 101                 rb_strlcpy(buf, data, sizeof(buf));
 102                 p = buf;
 103         }
 104
 105         if(*finished)
 106                 return NULL;
 107
 108         /* skip any whitespace */
 109         while(*p && IsSpace(*p))
 110                 p++;
 111
 112         if(EmptyString(p))
 113         {
 114                 *finished = 1;
 115                 return NULL;
 116         }
 117
 118         if(*p == '-')
 119         {
 120                 *negate = 1;
 121                 p++;
 122
 123                 /* someone sent a '-' without a parameter.. */
 124                 if(*p == '\0')
 125                         return NULL;
 126         }
 127
 128         if((s = strchr(p, ' ')))
 129                 *s++ = '\0';
 130
 131         if((cap = capability_find(cli_capindex, p)) != NULL)
 132         {
 133                 if(s)
 134                         p = s;
 135                 else
 136                         *finished = 1;
 137         }
 138
 139         return cap;
 140 }
 141
 142 /* clicap_generate()
 143  *   Generates a list of capabilities.
 144  *
 145  * Inputs: client to send to, subcmd to send,
 146  *         flags to match against: 0 to do none, -1 if client has no flags,
 147  *         int to whether we are doing CAP CLEAR
 148  * Outputs: None
 149  */
 150 static void
 151 clicap_generate(struct Client *source_p, const char *subcmd, int flags, int clear)
 152 {
 153         char buf[BUFSIZE] = { 0 };
 154         char capbuf[BUFSIZE] = { 0 };
 155         int buflen = 0;
 156         int curlen, mlen;
 157         struct CapabilityEntry *entry;
 158         struct DictionaryIter iter;
 159
 160         mlen = snprintf(buf, sizeof buf, ":%s CAP %s %s",
 161                         me.name,
 162                         EmptyString(source_p->name) ? "*" : source_p->name,
 163                         subcmd);
 164
 165         /* shortcut, nothing to do */
 166         if(flags == -1)
 167         {
 168                 sendto_one(source_p, "%s :", buf);
 169                 return;
 170         }
 171
 172         DICTIONARY_FOREACH(entry, &iter, cli_capindex->cap_dict)
 173         {
 174                 size_t caplen = 0;
 175                 struct ClientCapability *clicap = entry->ownerdata;
 176                 const char *data = NULL;
 177
 178                 if(flags)
 179                 {
 180                         if(!IsCapableEntry(source_p, entry))
 181                                 continue;
 182                         /* they are capable of this, check sticky */
 183                         else if(clear && HasCapabilityFlag(entry, CLICAP_FLAGS_STICKY))
 184                                 continue;
 185                 }
 186
 187                 if (!clicap_visible(source_p, entry))
 188                         continue;
 189
 190                 caplen = strlen(entry->cap);
 191                 if (!flags && (source_p->flags & FLAGS_CLICAP_DATA) && clicap != NULL && clicap->data != NULL)
 192                         data = clicap->data(source_p);
 193
 194                 if (data != NULL)
 195                         caplen += strlen(data) + 1;
 196
 197                 /* \r\n\0, possible "-~=", space, " *" */
 198                 if(buflen + mlen >= BUFSIZE - 10)
 199                 {
 200                         /* remove our trailing space -- if buflen == mlen
 201                          * here, we didnt even succeed in adding one.
 202                          */
 203                         capbuf[buflen] = '\0';
 204
 205                         sendto_one(source_p, "%s * :%s", buf, capbuf);
 206
 207                         buflen = mlen;
 208                         memset(capbuf, 0, sizeof capbuf);
 209                 }
 210
 211                 buflen = rb_snprintf_append(capbuf, sizeof capbuf, "%s%s%s%s ",
 212                                 clear ? "-" : "", entry->cap, data != NULL ? "=" : "", data != NULL ? data : "");
 213         }
 214
 215         /* remove trailing space */
 216         capbuf[buflen] = '\0';
 217
 218         sendto_one(source_p, "%s :%s", buf, capbuf);
 219 }
 220
 221 static void
 222 cap_ack(struct Client *source_p, const char *arg)
 223 {
 224         struct CapabilityEntry *cap;
 225         int capadd = 0, capdel = 0;
 226         int finished = 0, negate;
 227
 228         if(EmptyString(arg))
 229                 return;
 230
 231         for(cap = clicap_find(arg, &negate, &finished); cap;
 232             cap = clicap_find(NULL, &negate, &finished))
 233         {
 234                 /* sent an ACK for something they havent REQd */
 235                 if(!IsCapableEntry(source_p, cap))
 236                         continue;
 237
 238                 if(negate)
 239                 {
 240                         /* dont let them ack something sticky off */
 241                         if(HasCapabilityFlag(cap, CLICAP_FLAGS_STICKY))
 242                                 continue;
 243
 244                         capdel |= (1 << cap->value);
 245                 }
 246                 else
 247                         capadd |= (1 << cap->value);
 248         }
 249
 250         source_p->localClient->caps |= capadd;
 251         source_p->localClient->caps &= ~capdel;
 252 }
 253
 254 static void
 255 cap_clear(struct Client *source_p, const char *arg)
 256 {
 257         clicap_generate(source_p, "ACK",
 258                         source_p->localClient->caps ? source_p->localClient->caps : -1, 1);
 259
 260         source_p->localClient->caps = 0;
 261 }
 262
 263 static void
 264 cap_end(struct Client *source_p, const char *arg)
 265 {
 266         if(IsRegistered(source_p))
 267                 return;
 268
 269         source_p->flags &= ~FLAGS_CLICAP;
 270
 271         if(source_p->name[0] && source_p->flags & FLAGS_SENTUSER)
 272         {
 273                 register_local_user(source_p, source_p);
 274         }
 275 }
 276
 277 static void
 278 cap_list(struct Client *source_p, const char *arg)
 279 {
 280         /* list of what theyre currently using */
 281         clicap_generate(source_p, "LIST",
 282                         source_p->localClient->caps ? source_p->localClient->caps : -1, 0);
 283 }
 284
 285 static void
 286 cap_ls(struct Client *source_p, const char *arg)
 287 {
 288         if(!IsRegistered(source_p))
 289                 source_p->flags |= FLAGS_CLICAP;
 290
 291         if (arg != NULL && !strcmp(arg, "302"))
 292         {
 293                 source_p->flags |= FLAGS_CLICAP_DATA;
 294                 source_p->localClient->caps |= CLICAP_CAP_NOTIFY;
 295         }
 296
 297         /* list of what we support */
 298         clicap_generate(source_p, "LS", 0, 0);
 299 }
 300
 301 static void
 302 cap_req(struct Client *source_p, const char *arg)
 303 {
 304         char buf[BUFSIZE];
 305         char pbuf[2][BUFSIZE];
 306         struct CapabilityEntry *cap;
 307         int buflen, plen;
 308         int i = 0;
 309         int capadd = 0, capdel = 0;
 310         int finished = 0, negate;
 311
 312         if(!IsRegistered(source_p))
 313                 source_p->flags |= FLAGS_CLICAP;
 314
 315         if(EmptyString(arg))
 316                 return;
 317
 318         buflen = snprintf(buf, sizeof(buf), ":%s CAP %s ACK",
 319                         me.name, EmptyString(source_p->name) ? "*" : source_p->name);
 320
 321         pbuf[0][0] = '\0';
 322         plen = 0;
 323
 324         for(cap = clicap_find(arg, &negate, &finished); cap;
 325             cap = clicap_find(NULL, &negate, &finished))
 326         {
 327                 size_t namelen = strlen(cap->cap);
 328
 329                 /* filled the first array, but cant send it in case the
 330                  * request fails.  one REQ should never fill more than two
 331                  * buffers --fl
 332                  */
 333                 if(buflen + plen + namelen + 6 >= BUFSIZE)
 334                 {
 335                         pbuf[1][0] = '\0';
 336                         plen = 0;
 337                         i = 1;
 338                 }
 339
 340                 if(negate)
 341                 {
 342                         if(HasCapabilityFlag(cap, CLICAP_FLAGS_STICKY))
 343                         {
 344                                 finished = 0;
 345                                 break;
 346                         }
 347
 348                         strcat(pbuf[i], "-");
 349                         plen++;
 350
 351                         capdel |= (1 << cap->value);
 352                 }
 353                 else
 354                 {
 355                         if (!clicap_visible(source_p, cap))
 356                         {
 357                                 finished = 0;
 358                                 break;
 359                         }
 360
 361                         capadd |= (1 << cap->value);
 362                 }
 363
 364                 /* XXX this probably should exclude REQACK'd caps from capadd/capdel, but keep old behaviour for now */
 365                 if(HasCapabilityFlag(cap, CLICAP_FLAGS_REQACK))
 366                 {
 367                         strcat(pbuf[i], "~");
 368                         plen++;
 369                 }
 370
 371                 strcat(pbuf[i], cap->cap);
 372                 if (!finished) {
 373                         strcat(pbuf[i], " ");
 374                         plen += (namelen + 1);
 375                 }
 376         }
 377
 378         if(!finished)
 379         {
 380                 sendto_one(source_p, ":%s CAP %s NAK :%s",
 381                         me.name, EmptyString(source_p->name) ? "*" : source_p->name, arg);
 382                 return;
 383         }
 384
 385         if(i)
 386         {
 387                 sendto_one(source_p, "%s * :%s", buf, pbuf[0]);
 388                 sendto_one(source_p, "%s :%s", buf, pbuf[1]);
 389         }
 390         else
 391                 sendto_one(source_p, "%s :%s", buf, pbuf[0]);
 392
 393         source_p->localClient->caps |= capadd;
 394         source_p->localClient->caps &= ~capdel;
 395 }
 396
 397 static struct clicap_cmd
 398 {
 399         const char *cmd;
 400         void (*func)(struct Client *source_p, const char *arg);
 401 } clicap_cmdlist[] = {
 402         /* This list *MUST* be in alphabetical order */
 403         { "ACK",        cap_ack         },
 404         { "CLEAR",      cap_clear       },
 405         { "END",        cap_end         },
 406         { "LIST",       cap_list        },
 407         { "LS",         cap_ls          },
 408         { "REQ",        cap_req         },
 409 };
 410
 411 static int
 412 clicap_cmd_search(const char *command, struct clicap_cmd *entry)
 413 {
 414         return irccmp(command, entry->cmd);
 415 }
 416
 417 static int
 418 m_cap(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
 419 {
 420         struct clicap_cmd *cmd;
 421
 422         if(!(cmd = bsearch(parv[1], clicap_cmdlist,
 423                                 sizeof(clicap_cmdlist) / sizeof(struct clicap_cmd),
 424                                 sizeof(struct clicap_cmd), (bqcmp) clicap_cmd_search)))
 425         {
 426                 sendto_one(source_p, form_str(ERR_INVALIDCAPCMD),
 427                                 me.name, EmptyString(source_p->name) ? "*" : source_p->name,
 428                                 parv[1]);
 429                 return 0;
 430         }
 431
 432         (cmd->func)(source_p, parv[2]);
 433         return 0;
 434 }