citadel/modules/xmpp/xmpp_presence.c

   1 /*
   2  * Handle XMPP presence exchanges
   3  *
   4  * Copyright (c) 2007-2010 by Art Cancro
   5  *
   6  * This program is open source software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include "sysdep.h"
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25 #include <stdio.h>
  26 #include <fcntl.h>
  27 #include <signal.h>
  28 #include <pwd.h>
  29 #include <errno.h>
  30 #include <sys/types.h>
  31 #include <assert.h>
  32
  33 #if TIME_WITH_SYS_TIME
  34 # include <sys/time.h>
  35 # include <time.h>
  36 #else
  37 # if HAVE_SYS_TIME_H
  38 #  include <sys/time.h>
  39 # else
  40 #  include <time.h>
  41 # endif
  42 #endif
  43
  44 #include <sys/wait.h>
  45 #include <string.h>
  46 #include <limits.h>
  47 #include <ctype.h>
  48 #include <expat.h>
  49 #include <libcitadel.h>
  50 #include "citadel.h"
  51 #include "server.h"
  52 #include "citserver.h"
  53 #include "support.h"
  54 #include "config.h"
  55 #include "internet_addressing.h"
  56 #include "md5.h"
  57 #include "ctdl_module.h"
  58 #include "serv_xmpp.h"
  59
  60
  61
  62 /*
  63  * Indicate the presence of another user to the client
  64  * (used in several places)
  65  */
  66 void xmpp_indicate_presence(char *presence_jid)
  67 {
  68         XPrint(HKEY("presence"),
  69                XPROPERTY("from", presence_jid, strlen(presence_jid)),
  70                XPROPERTY("to",  XMPP->client_jid, strlen(XMPP->client_jid)),
  71                TYPE_ARGEND);
  72 }
  73
  74
  75
  76 /*
  77  * Convenience function to determine whether any given session is 'visible' to any other given session,
  78  * and is capable of receiving instant messages from that session.
  79  */
  80 int xmpp_is_visible(struct CitContext *cptr, struct CitContext *to_whom) {
  81         int aide = (to_whom->user.axlevel >= AxAideU);
  82
  83         if (    (cptr->logged_in)
  84                 &&      (((cptr->cs_flags&CS_STEALTH)==0) || (aide))    /* aides see everyone */
  85                 &&      (cptr->user.usernum != to_whom->user.usernum)   /* don't show myself */
  86                 &&      (cptr->can_receive_im)                          /* IM-capable session */
  87         ) {
  88                 return(1);
  89         }
  90         else {
  91                 return(0);
  92         }
  93 }
  94
  95
  96 /*
  97  * Initial dump of the entire wholist
  98  * Respond to a <presence> update by firing back with presence information
  99  * on the entire wholist.  Check this assumption, it's probably wrong.
 100  */
 101 void xmpp_wholist_presence_dump(void *data, const char *supplied_el, const char **attr)
 102 {
 103         struct CitContext *cptr = NULL;
 104         int nContexts, i;
 105
 106         cptr = CtdlGetContextArray(&nContexts);
 107         if (!cptr) {
 108                 return;
 109         }
 110
 111         for (i=0; i<nContexts; i++) {
 112                 if (xmpp_is_visible(&cptr[i], CC)) {
 113                         xmpp_indicate_presence(cptr[i].cs_inet_email);
 114                 }
 115         }
 116         free(cptr);
 117 }
 118
 119
 120 /*
 121  * Function to remove a buddy subscription and delete from the roster
 122  * (used in several places)
 123  */
 124 void xmpp_destroy_buddy(char *presence_jid, int aggressively) {
 125         static int unsolicited_id = 1;
 126         struct CitContext *CCC = CC;
 127         char Buf[64];
 128         long blen;
 129
 130         if (!presence_jid) return;
 131         if (!XMPP) return;
 132         if (!XMPP->client_jid) return;
 133
 134         /* Transmit non-presence information */
 135         XPrint(HKEY("presence"), XCLOSED,
 136                XCPROPERTY("type", "unavailable"),
 137                XPROPERTY("from", presence_jid, strlen(presence_jid)),
 138                XPROPERTY("to",  XMPP->client_jid, strlen(XMPP->client_jid)),
 139                TYPE_ARGEND);
 140
 141         /*
 142          * Setting the "aggressively" flag also sends an "unsubscribed" presence update.
 143          * We only ask for this when flushing the client side roster, because if we do it
 144          * in the middle of a session when another user logs off, some clients (Jitsi) interpret
 145          * it as a rejection of a subscription request.
 146          */
 147         if (aggressively) {
 148                 XPrint(HKEY("presence"), XCLOSED,
 149                        XCPROPERTY("type", "unsubscribed"),
 150                        XPROPERTY("from", presence_jid, strlen(presence_jid)),
 151                        XPROPERTY("to",  XMPP->client_jid, strlen(XMPP->client_jid)),
 152                        TYPE_ARGEND);
 153         }
 154
 155         // FIXME ... we should implement xmpp_indicate_nonpresence so we can use it elsewhere
 156
 157         blen = snprintf(Buf, sizeof(Buf), "unbuddy_%x", ++unsolicited_id);
 158
 159         /* Do an unsolicited roster update that deletes the contact. */
 160         XPrint(HKEY("iq"), 0,
 161                XCPROPERTY("type", "result"),
 162                XPROPERTY("from", CCC->cs_inet_email, strlen(CCC->cs_inet_email)),
 163                XPROPERTY("to",  XMPP->client_jid, strlen(XMPP->client_jid)),
 164                XPROPERTY("id",  Buf, blen),
 165                TYPE_ARGEND);
 166
 167         XPrint(HKEY("query"), 0,
 168                XCPROPERTY("xmlns", "jabber:iq:roster"),
 169                TYPE_ARGEND);
 170
 171         XPrint(HKEY("item"), 0,
 172                XCPROPERTY("subscription", "remove"),
 173                XPROPERTY("jid", presence_jid, strlen(presence_jid)),
 174                TYPE_ARGEND);
 175
 176         XPrint(HKEY("group"), XCLOSED,
 177                XCFGBODY(c_humannode),
 178                TYPE_ARGEND);
 179         XPUT("</item>"
 180              "</query>"
 181              "</iq>"
 182         );
 183 }
 184
 185
 186 /*
 187  * When a user logs in or out of the local Citadel system, notify all XMPP sessions about it.
 188  * THIS FUNCTION HAS A BUG IN IT THAT ENUMERATES THE SESSIONS WRONG.
 189  */
 190 void xmpp_presence_notify(char *presence_jid, int event_type) {
 191         struct CitContext *cptr;
 192         static int unsolicited_id;
 193         int visible_sessions = 0;
 194         int nContexts, i;
 195         int which_cptr_is_relevant = (-1);
 196
 197         if (IsEmptyStr(presence_jid)) return;
 198         if (CC->kill_me) return;
 199
 200         cptr = CtdlGetContextArray(&nContexts);
 201         if (!cptr) {
 202                 return;
 203         }
 204
 205         /* Count the visible sessions for this user */
 206         for (i=0; i<nContexts; i++) {
 207                 if ( (!strcasecmp(cptr[i].cs_inet_email, presence_jid))
 208                    && (xmpp_is_visible(&cptr[i], CC))
 209                 )  {
 210                         ++visible_sessions;
 211                         which_cptr_is_relevant = i;
 212                 }
 213         }
 214
 215         XMPP_syslog(LOG_DEBUG, "%d sessions for <%s> are now visible to session %d\n",
 216                     visible_sessions, presence_jid, CC->cs_pid);
 217
 218         if ( (event_type == XMPP_EVT_LOGIN) && (visible_sessions == 1) ) {
 219                 long blen;
 220                 char Buf[64];
 221
 222                 XMPP_syslog(LOG_DEBUG, "Telling session %d that <%s> logged in\n",
 223                             CC->cs_pid, presence_jid);
 224
 225                 /* Do an unsolicited roster update that adds a new contact. */
 226                 assert(which_cptr_is_relevant >= 0);
 227
 228                 blen = snprintf(Buf, sizeof(Buf), "unsolicited_%x", ++unsolicited_id);
 229
 230                 XPrint(HKEY("iq"), 0,
 231                        XCPROPERTY("type", "result"),
 232                        XPROPERTY("id", Buf, blen),
 233                        TYPE_ARGEND);
 234
 235                 XPrint(HKEY("query"), 0,
 236                        XCPROPERTY("xmlns", "jabber:iq:roster"),
 237                        TYPE_ARGEND);
 238
 239                 xmpp_roster_item(&cptr[which_cptr_is_relevant]);
 240                 XPUT("</query></iq>");
 241
 242                 /* Transmit presence information */
 243                 xmpp_indicate_presence(presence_jid);
 244         }
 245
 246         if (visible_sessions == 0) {
 247                 XMPP_syslog(LOG_DEBUG, "Telling session %d that <%s> logged out\n",
 248                             CC->cs_pid, presence_jid);
 249                 xmpp_destroy_buddy(presence_jid, 0);    /* non aggressive presence update */
 250         }
 251
 252         free(cptr);
 253 }
 254
 255
 256
 257 void xmpp_fetch_mortuary_backend(long msgnum, void *userdata) {
 258         HashList *mortuary = (HashList *) userdata;
 259         struct CtdlMessage *msg;
 260         char *ptr = NULL;
 261         char *lasts = NULL;
 262
 263         msg = CtdlFetchMessage(msgnum, 1);
 264         if (msg == NULL) {
 265                 return;
 266         }
 267
 268         /* now add anyone we find into the hashlist */
 269
 270         /* skip past the headers */
 271         ptr = strstr(msg->cm_fields[eMesageText], "\n\n");
 272         if (ptr != NULL) {
 273                 ptr += 2;
 274         }
 275         else {
 276                 ptr = strstr(msg->cm_fields[eMesageText], "\n\r\n");
 277                 if (ptr != NULL) {
 278                         ptr += 3;
 279                 }
 280         }
 281
 282         /* the remaining lines are addresses */
 283         if (ptr != NULL) {
 284                 ptr = strtok_r(ptr, "\n", &lasts);
 285                 while (ptr != NULL) {
 286                         char *pch = strdup(ptr);
 287                         Put(mortuary, pch, strlen(pch), pch, NULL);
 288                         ptr = strtok_r(NULL, "\n", &lasts);
 289                 }
 290         }
 291
 292         CM_Free(msg);
 293 }
 294
 295
 296
 297 /*
 298  * Fetch the "mortuary" - a list of dead buddies which we keep around forever
 299  * so we can remove them from any client's roster that still has them listed
 300  */
 301 HashList *xmpp_fetch_mortuary(void) {
 302         HashList *mortuary = NewHash(1, NULL);
 303         if (!mortuary) {
 304                 XMPPM_syslog(LOG_ALERT, "NewHash() failed!\n");
 305                 return(NULL);
 306         }
 307
 308         if (CtdlGetRoom(&CC->room, USERCONFIGROOM) != 0) {
 309                 /* no config room exists - no further processing is required. */
 310                 return(mortuary);
 311         }
 312         CtdlForEachMessage(MSGS_LAST, 1, NULL, XMPPMORTUARY, NULL,
 313                 xmpp_fetch_mortuary_backend, (void *)mortuary );
 314
 315         return(mortuary);
 316 }
 317
 318
 319
 320 /*
 321  * Fetch the "mortuary" - a list of dead buddies which we keep around forever
 322  * so we can remove them from any client's roster that still has them listed
 323  */
 324 void xmpp_store_mortuary(HashList *mortuary) {
 325         HashPos *HashPos;
 326         long len;
 327         void *Value;
 328         const char *Key;
 329         StrBuf *themsg;
 330
 331         themsg = NewStrBuf();
 332         StrBufPrintf(themsg,    "Content-type: " XMPPMORTUARY "\n"
 333                                 "Content-transfer-encoding: 7bit\n"
 334                                 "\n"
 335         );
 336
 337         HashPos = GetNewHashPos(mortuary, 0);
 338         while (GetNextHashPos(mortuary, HashPos, &len, &Key, &Value) != 0)
 339         {
 340                 StrBufAppendPrintf(themsg, "%s\n", (char *)Value);
 341         }
 342         DeleteHashPos(&HashPos);
 343
 344         /* FIXME temp crap
 345         StrBufAppendPrintf(themsg, "foo@bar.com\n");
 346         StrBufAppendPrintf(themsg, "baz@quux.com\n");
 347         StrBufAppendPrintf(themsg, "haha%c\n", 1);
 348         StrBufAppendPrintf(themsg, "baaaz@quux.com\n");
 349         StrBufAppendPrintf(themsg, "baaaz@quuuuuux.com\n");
 350         */
 351
 352         /* Delete the old mortuary */
 353         CtdlDeleteMessages(USERCONFIGROOM, NULL, 0, XMPPMORTUARY);
 354
 355         /* And save the new one to disk */
 356         quickie_message("Citadel", NULL, NULL, USERCONFIGROOM, ChrPtr(themsg), 4, "XMPP Mortuary");
 357         FreeStrBuf(&themsg);
 358 }
 359
 360
 361
 362 /*
 363  * Upon logout we make an attempt to delete the whole roster, in order to
 364  * try to keep "ghost" buddies from remaining in the client-side roster.
 365  *
 366  * Since the client is probably not still alive, also remember the current
 367  * roster for next time so we can delete dead buddies then.
 368  */
 369 void xmpp_massacre_roster(void)
 370 {
 371         struct CitContext *cptr;
 372         int nContexts, i;
 373         HashList *mortuary = xmpp_fetch_mortuary();
 374
 375         cptr = CtdlGetContextArray(&nContexts);
 376         if (cptr) {
 377                 for (i=0; i<nContexts; i++) {
 378                         if (xmpp_is_visible(&cptr[i], CC)) {
 379                                 if (mortuary) {
 380                                         char *buddy = strdup(cptr[i].cs_inet_email);
 381                                         Put(mortuary, buddy, strlen(buddy), buddy, NULL);
 382                                 }
 383                         }
 384                 }
 385                 free (cptr);
 386         }
 387
 388         if (mortuary) {
 389                 xmpp_store_mortuary(mortuary);
 390                 DeleteHash(&mortuary);
 391         }
 392 }
 393
 394
 395
 396 /*
 397  * Stupidly, XMPP does not specify a way to tell the client to flush its client-side roster
 398  * and prepare to receive a new one.  So instead we remember every buddy we've ever told the
 399  * client about, and push delete operations out at the beginning of a session.
 400  *
 401  * We omit any users who happen to be online right now, but we still keep them in the mortuary,
 402  * which needs to be maintained as a list of every buddy the user has ever seen.  We don't know
 403  * when they're connecting from the same client and when they're connecting from a different client,
 404  * so we have no guarantee of what is in the client side roster at connect time.
 405  */
 406 void xmpp_delete_old_buddies_who_no_longer_exist_from_the_client_roster(void)
 407 {
 408         long len;
 409         void *Value;
 410         const char *Key;
 411         struct CitContext *cptr;
 412         int nContexts, i;
 413         int online_now = 0;
 414         HashList *mortuary = xmpp_fetch_mortuary();
 415         HashPos *HashPos = GetNewHashPos(mortuary, 0);
 416
 417         /* we need to omit anyone who is currently online */
 418         cptr = CtdlGetContextArray(&nContexts);
 419
 420         /* go through the list of users in the mortuary... */
 421         while (GetNextHashPos(mortuary, HashPos, &len, &Key, &Value) != 0)
 422         {
 423
 424                 online_now = 0;
 425                 if (cptr) for (i=0; i<nContexts; i++) {
 426                         if (xmpp_is_visible(&cptr[i], CC)) {
 427                                 if (!strcasecmp(cptr[i].cs_inet_email, (char *)Value)) {
 428                                         online_now = 1;
 429                                 }
 430                         }
 431                 }
 432
 433                 if (!online_now) {
 434                         xmpp_destroy_buddy((char *)Value, 1);   /* aggressive presence update */
 435                 }
 436
 437         }
 438         DeleteHashPos(&HashPos);
 439         DeleteHash(&mortuary);
 440         free(cptr);
 441 }
 442
 443
 444 CTDL_MODULE_INIT(xmpp_presence)
 445 {
 446         if (!threading) {
 447                 AddXMPPEndHandler(HKEY("presence"), xmpp_wholist_presence_dump, 0);
 448         }
 449         return "xmpp_presence";
 450 }