citadel/modules/instmsg/serv_instmsg.c

   1 /*
   2  * This module handles instant messaging between users.
   3  *
   4  * Copyright (c) 1987-2020 by the citadel.org team
   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 version 3.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include "sysdep.h"
  16 #include <stdlib.h>
  17 #include <unistd.h>
  18 #include <stdio.h>
  19 #include <fcntl.h>
  20 #include <signal.h>
  21 #include <pwd.h>
  22 #include <errno.h>
  23 #include <sys/types.h>
  24
  25 #if TIME_WITH_SYS_TIME
  26 # include <sys/time.h>
  27 # include <time.h>
  28 #else
  29 # if HAVE_SYS_TIME_H
  30 #  include <sys/time.h>
  31 # else
  32 #  include <time.h>
  33 # endif
  34 #endif
  35
  36 #include <sys/wait.h>
  37 #include <string.h>
  38 #include <limits.h>
  39 #include <libcitadel.h>
  40 #include "citadel.h"
  41 #include "server.h"
  42 #include "serv_instmsg.h"
  43 #include "citserver.h"
  44 #include "support.h"
  45 #include "config.h"
  46 #include "msgbase.h"
  47 #include "user_ops.h"
  48 #include "ctdl_module.h"
  49
  50 struct imlog {
  51         struct imlog *next;
  52         long usernums[2];
  53         char usernames[2][128];
  54         time_t lastmsg;
  55         int last_serial;
  56         StrBuf *conversation;
  57 };
  58
  59 struct imlog *imlist = NULL;
  60
  61 /*
  62  * This function handles the logging of instant messages to disk.
  63  */
  64 void log_instant_message(struct CitContext *me, struct CitContext *them, char *msgtext, int serial_number)
  65 {
  66         long usernums[2];
  67         long t;
  68         struct imlog *iptr = NULL;
  69         struct imlog *this_im = NULL;
  70
  71         memset(usernums, 0, sizeof usernums);
  72         usernums[0] = me->user.usernum;
  73         usernums[1] = them->user.usernum;
  74
  75         /* Always put the lower user number first, so we can use the array as a hash value which
  76          * represents a pair of users.  For a broadcast message one of the users will be 0.
  77          */
  78         if (usernums[0] > usernums[1]) {
  79                 t = usernums[0];
  80                 usernums[0] = usernums[1];
  81                 usernums[1] = t;
  82         }
  83
  84         begin_critical_section(S_IM_LOGS);
  85
  86         /* Look for an existing conversation in the hash table.
  87          * If not found, create a new one.
  88          */
  89
  90         this_im = NULL;
  91         for (iptr = imlist; iptr != NULL; iptr = iptr->next) {
  92                 if ((iptr->usernums[0] == usernums[0]) && (iptr->usernums[1] == usernums[1])) {
  93                         /* Existing conversation */
  94                         this_im = iptr;
  95                 }
  96         }
  97         if (this_im == NULL) {
  98                 /* New conversation */
  99                 this_im = malloc(sizeof(struct imlog));
 100                 memset(this_im, 0, sizeof (struct imlog));
 101                 this_im->usernums[0] = usernums[0];
 102                 this_im->usernums[1] = usernums[1];
 103                 /* usernames[] and usernums[] might not be in the same order.  This is not an error. */
 104                 if (me) {
 105                         safestrncpy(this_im->usernames[0], me->user.fullname, sizeof this_im->usernames[0]);
 106                 }
 107                 if (them) {
 108                         safestrncpy(this_im->usernames[1], them->user.fullname, sizeof this_im->usernames[1]);
 109                 }
 110                 this_im->conversation = NewStrBuf();
 111                 this_im->next = imlist;
 112                 imlist = this_im;
 113                 StrBufAppendBufPlain(this_im->conversation, HKEY("<html><body>\r\n"), 0);
 114         }
 115
 116         /* Since it's possible for this function to get called more than once if a user is logged
 117          * in on multiple sessions, we use the message's serial number to keep track of whether
 118          * we've already logged it.
 119          */
 120         if (this_im->last_serial != serial_number)
 121         {
 122                 this_im->lastmsg = time(NULL);          /* Touch the timestamp so we know when to flush */
 123                 this_im->last_serial = serial_number;
 124                 StrBufAppendBufPlain(this_im->conversation, HKEY("<p><b>"), 0);
 125                 StrBufAppendBufPlain(this_im->conversation, me->user.fullname, -1, 0);
 126                 StrBufAppendBufPlain(this_im->conversation, HKEY(":</b> "), 0);
 127                 StrEscAppend(this_im->conversation, NULL, msgtext, 0, 0);
 128                 StrBufAppendBufPlain(this_im->conversation, HKEY("</p>\r\n"), 0);
 129         }
 130         end_critical_section(S_IM_LOGS);
 131 }
 132
 133
 134 /*
 135  * Delete any remaining instant messages
 136  */
 137 void delete_instant_messages(void) {
 138         struct ExpressMessage *ptr;
 139
 140         begin_critical_section(S_SESSION_TABLE);
 141         while (CC->FirstExpressMessage != NULL) {
 142                 ptr = CC->FirstExpressMessage->next;
 143                 if (CC->FirstExpressMessage->text != NULL)
 144                         free(CC->FirstExpressMessage->text);
 145                 free(CC->FirstExpressMessage);
 146                 CC->FirstExpressMessage = ptr;
 147         }
 148         end_critical_section(S_SESSION_TABLE);
 149 }
 150
 151
 152 /*
 153  * Retrieve instant messages
 154  */
 155 void cmd_gexp(char *argbuf) {
 156         struct ExpressMessage *ptr;
 157
 158         if (CC->FirstExpressMessage == NULL) {
 159                 cprintf("%d No instant messages waiting.\n", ERROR + MESSAGE_NOT_FOUND);
 160                 return;
 161         }
 162
 163         begin_critical_section(S_SESSION_TABLE);
 164         ptr = CC->FirstExpressMessage;
 165         CC->FirstExpressMessage = CC->FirstExpressMessage->next;
 166         end_critical_section(S_SESSION_TABLE);
 167
 168         cprintf("%d %d|%ld|%d|%s|%s|%s\n",
 169                 LISTING_FOLLOWS,
 170                 ((ptr->next != NULL) ? 1 : 0),          /* more msgs? */
 171                 (long)ptr->timestamp,                   /* time sent */
 172                 ptr->flags,                             /* flags */
 173                 ptr->sender,                            /* sender of msg */
 174                 CtdlGetConfigStr("c_nodename"),         /* static for now (and possibly deprecated) */
 175                 ptr->sender_email                       /* email or jid of sender */
 176         );
 177
 178         if (ptr->text != NULL) {
 179                 memfmout(ptr->text, "\n");
 180                 free(ptr->text);
 181         }
 182
 183         cprintf("000\n");
 184         free(ptr);
 185 }
 186
 187
 188 /*
 189  * Asynchronously deliver instant messages
 190  */
 191 void cmd_gexp_async(void) {
 192
 193         /* Only do this if the session can handle asynchronous protocol */
 194         if (CC->is_async == 0) return;
 195
 196         /* And don't do it if there's nothing to send. */
 197         if (CC->FirstExpressMessage == NULL) return;
 198
 199         cprintf("%d instant msg\n", ASYNC_MSG + ASYNC_GEXP);
 200 }
 201
 202
 203 /*
 204  * Back end support function for send_instant_message() and company
 205  */
 206 void add_xmsg_to_context(struct CitContext *ccptr, struct ExpressMessage *newmsg)
 207 {
 208         struct ExpressMessage *findend;
 209
 210         if (ccptr->FirstExpressMessage == NULL) {
 211                 ccptr->FirstExpressMessage = newmsg;
 212         }
 213         else {
 214                 findend = ccptr->FirstExpressMessage;
 215                 while (findend->next != NULL) {
 216                         findend = findend->next;
 217                 }
 218                 findend->next = newmsg;
 219         }
 220
 221         /* If the target context is a session which can handle asynchronous
 222          * messages, go ahead and set the flag for that.
 223          */
 224         set_async_waiting(ccptr);
 225 }
 226
 227
 228 /*
 229  * This is the back end to the instant message sending function.
 230  * Returns the number of users to which the message was sent.
 231  * Sending a zero-length message tests for recipients without sending messages.
 232  */
 233 int send_instant_message(char *lun, char *lem, char *x_user, char *x_msg)
 234 {
 235         int message_sent = 0;           /* number of successful sends */
 236         struct CitContext *ccptr;
 237         struct ExpressMessage *newmsg = NULL;
 238         int do_send = 0;                /* 1 = send message; 0 = only check for valid recipient */
 239         static int serial_number = 0;   /* this keeps messages from getting logged twice */
 240
 241         if (!IsEmptyStr(x_msg)) {
 242                 do_send = 1;
 243         }
 244
 245         /* find the target user's context and append the message */
 246         begin_critical_section(S_SESSION_TABLE);
 247         ++serial_number;
 248         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 249
 250                 if ( ((!strcasecmp(ccptr->user.fullname, x_user))
 251                     || (!strcasecmp(x_user, "broadcast")))
 252                     && (ccptr->can_receive_im)
 253                     && ((ccptr->disable_exp == 0)
 254                     || (CC->user.axlevel >= AxAideU)) ) {
 255                         if (do_send) {
 256                                 newmsg = (struct ExpressMessage *) malloc(sizeof (struct ExpressMessage));
 257                                 memset(newmsg, 0, sizeof (struct ExpressMessage));
 258                                 time(&(newmsg->timestamp));
 259                                 safestrncpy(newmsg->sender, lun, sizeof newmsg->sender);
 260                                 safestrncpy(newmsg->sender_email, lem, sizeof newmsg->sender_email);
 261                                 if (!strcasecmp(x_user, "broadcast")) {
 262                                         newmsg->flags |= EM_BROADCAST;
 263                                 }
 264                                 newmsg->text = strdup(x_msg);
 265
 266                                 add_xmsg_to_context(ccptr, newmsg);
 267
 268                                 /* and log it ... */
 269                                 if (ccptr != CC) {
 270                                         log_instant_message(CC, ccptr, newmsg->text, serial_number);
 271                                 }
 272                         }
 273                         ++message_sent;
 274                 }
 275         }
 276         end_critical_section(S_SESSION_TABLE);
 277         return (message_sent);
 278 }
 279
 280
 281 /*
 282  * send instant messages
 283  */
 284 void cmd_sexp(char *argbuf)
 285 {
 286         int message_sent = 0;
 287         char x_user[USERNAME_SIZE];
 288         char x_msg[1024];
 289         char *lem;
 290         char *x_big_msgbuf = NULL;
 291
 292         if ((!(CC->logged_in)) && (!(CC->internal_pgm))) {
 293                 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 294                 return;
 295         }
 296
 297         lem = CC->cs_principal_id;
 298
 299         extract_token(x_user, argbuf, 0, '|', sizeof x_user);
 300         extract_token(x_msg, argbuf, 1, '|', sizeof x_msg);
 301
 302         if (!x_user[0]) {
 303                 cprintf("%d You were not previously paged.\n", ERROR + NO_SUCH_USER);
 304                 return;
 305         }
 306         if ((!strcasecmp(x_user, "broadcast")) && (CC->user.axlevel < AxAideU)) {
 307                 cprintf("%d Higher access required to send a broadcast.\n",
 308                         ERROR + HIGHER_ACCESS_REQUIRED);
 309                 return;
 310         }
 311         /* This loop handles text-transfer pages */
 312         if (!strcmp(x_msg, "-")) {
 313                 message_sent = PerformXmsgHooks(CC->user.fullname, lem, x_user, "");
 314                 if (message_sent == 0) {
 315                         if (CtdlGetUser(NULL, x_user))
 316                                 cprintf("%d '%s' does not exist.\n",
 317                                                 ERROR + NO_SUCH_USER, x_user);
 318                         else
 319                                 cprintf("%d '%s' is not logged in "
 320                                                 "or is not accepting pages.\n",
 321                                                 ERROR + RESOURCE_NOT_OPEN, x_user);
 322                         return;
 323                 }
 324                 unbuffer_output();
 325                 cprintf("%d Transmit message (will deliver to %d users)\n",
 326                         SEND_LISTING, message_sent);
 327                 x_big_msgbuf = malloc(SIZ);
 328                 memset(x_big_msgbuf, 0, SIZ);
 329                 while (client_getln(x_msg, sizeof x_msg) >= 0 && strcmp(x_msg, "000")) {
 330                         x_big_msgbuf = realloc(x_big_msgbuf,
 331                                strlen(x_big_msgbuf) + strlen(x_msg) + 4);
 332                         if (!IsEmptyStr(x_big_msgbuf))
 333                            if (x_big_msgbuf[strlen(x_big_msgbuf)] != '\n')
 334                                 strcat(x_big_msgbuf, "\n");
 335                         strcat(x_big_msgbuf, x_msg);
 336                 }
 337                 PerformXmsgHooks(CC->user.fullname, lem, x_user, x_big_msgbuf);
 338                 free(x_big_msgbuf);
 339
 340                 /* This loop handles inline pages */
 341         } else {
 342                 message_sent = PerformXmsgHooks(CC->user.fullname, lem, x_user, x_msg);
 343
 344                 if (message_sent > 0) {
 345                         if (!IsEmptyStr(x_msg)) {
 346                                 cprintf("%d Message sent", CIT_OK);
 347                         }
 348                         else {
 349                                 cprintf("%d Ok to send message", CIT_OK);
 350                         }
 351                         if (message_sent > 1) {
 352                                 cprintf(" to %d users", message_sent);
 353                         }
 354                         cprintf(".\n");
 355                 } else {
 356                         if (CtdlGetUser(NULL, x_user)) {
 357                                 cprintf("%d '%s' does not exist.\n", ERROR + NO_SUCH_USER, x_user);
 358                         }
 359                         else {
 360                                 cprintf("%d '%s' is not logged in or is not accepting instant messages.\n",
 361                                                 ERROR + RESOURCE_NOT_OPEN, x_user);
 362                         }
 363                 }
 364
 365
 366         }
 367 }
 368
 369
 370 /*
 371  * Enter or exit paging-disabled mode
 372  */
 373 void cmd_dexp(char *argbuf)
 374 {
 375         int new_state;
 376
 377         if (CtdlAccessCheck(ac_logged_in)) return;
 378
 379         new_state = extract_int(argbuf, 0);
 380         if ((new_state == 0) || (new_state == 1)) {
 381                 CC->disable_exp = new_state;
 382         }
 383
 384         cprintf("%d %d\n", CIT_OK, CC->disable_exp);
 385 }
 386
 387
 388 /*
 389  * Request client termination
 390  */
 391 void cmd_reqt(char *argbuf) {
 392         struct CitContext *ccptr;
 393         int sessions = 0;
 394         int which_session;
 395         struct ExpressMessage *newmsg;
 396
 397         if (CtdlAccessCheck(ac_aide)) return;
 398         which_session = extract_int(argbuf, 0);
 399
 400         begin_critical_section(S_SESSION_TABLE);
 401         for (ccptr = ContextList; ccptr != NULL; ccptr = ccptr->next) {
 402                 if ((ccptr->cs_pid == which_session) || (which_session == 0)) {
 403
 404                         newmsg = (struct ExpressMessage *)
 405                                 malloc(sizeof (struct ExpressMessage));
 406                         memset(newmsg, 0,
 407                                 sizeof (struct ExpressMessage));
 408                         time(&(newmsg->timestamp));
 409                         safestrncpy(newmsg->sender, CC->user.fullname,
 410                                     sizeof newmsg->sender);
 411                         newmsg->flags |= EM_GO_AWAY;
 412                         newmsg->text = strdup("Automatic logoff requested.");
 413
 414                         add_xmsg_to_context(ccptr, newmsg);
 415                         ++sessions;
 416
 417                 }
 418         }
 419         end_critical_section(S_SESSION_TABLE);
 420         cprintf("%d Sent termination request to %d sessions.\n", CIT_OK, sessions);
 421 }
 422
 423
 424 /*
 425  * This is the back end for flush_conversations_to_disk()
 426  * At this point we've isolated a single conversation (struct imlog)
 427  * and are ready to write it to disk.
 428  */
 429 void flush_individual_conversation(struct imlog *im) {
 430         struct CtdlMessage *msg;
 431         long msgnum = 0;
 432         char roomname[ROOMNAMELEN];
 433         StrBuf *MsgBuf, *FullMsgBuf;
 434
 435         StrBufAppendBufPlain(im->conversation, HKEY(
 436                 "</body>\r\n"
 437                 "</html>\r\n"
 438                 ), 0
 439         );
 440
 441         MsgBuf = StrBufRFC2047encodeMessage(im->conversation);
 442         FlushStrBuf(im->conversation);
 443         FullMsgBuf = NewStrBufPlain(NULL, StrLength(im->conversation) + 100);
 444
 445         StrBufAppendBufPlain(FullMsgBuf, HKEY(
 446                 "Content-type: text/html; charset=UTF-8\r\n"
 447                 "Content-Transfer-Encoding: quoted-printable\r\n"
 448                 "\r\n"
 449                 ), 0
 450         );
 451         StrBufAppendBuf (FullMsgBuf, MsgBuf, 0);
 452         FreeStrBuf(&MsgBuf);
 453
 454         msg = malloc(sizeof(struct CtdlMessage));
 455         memset(msg, 0, sizeof(struct CtdlMessage));
 456         msg->cm_magic = CTDLMESSAGE_MAGIC;
 457         msg->cm_anon_type = MES_NORMAL;
 458         msg->cm_format_type = FMT_RFC822;
 459         if (!IsEmptyStr(im->usernames[0])) {
 460                 CM_SetField(msg, eAuthor, im->usernames[0], strlen(im->usernames[0]));
 461         } else {
 462                 CM_SetField(msg, eAuthor, HKEY("Citadel"));
 463         }
 464         if (!IsEmptyStr(im->usernames[1])) {
 465                 CM_SetField(msg, eRecipient, im->usernames[1], strlen(im->usernames[1]));
 466         }
 467
 468         CM_SetField(msg, eOriginalRoom, HKEY(PAGELOGROOM));
 469         CM_SetAsFieldSB(msg, eMesageText, &FullMsgBuf); /* we own this memory now */
 470
 471         /* Start with usernums[1] because it's guaranteed to be higher than usernums[0],
 472          * so if there's only one party, usernums[0] will be zero but usernums[1] won't.
 473          * Create the room if necessary.  Note that we create as a type 5 room rather
 474          * than 4, which indicates that it's a personal room but we've already supplied
 475          * the namespace prefix.
 476          *
 477          * In the unlikely event that usernums[1] is zero, a room with an invalid namespace
 478          * prefix will be created.  That's ok because the auto-purger will clean it up later.
 479          */
 480         snprintf(roomname, sizeof roomname, "%010ld.%s", im->usernums[1], PAGELOGROOM);
 481         CtdlCreateRoom(roomname, 5, "", 0, 1, 1, VIEW_BBS);
 482         msgnum = CtdlSubmitMsg(msg, NULL, roomname);
 483         CM_Free(msg);
 484
 485         /* If there is a valid user number in usernums[0], save a copy for them too. */
 486         if (im->usernums[0] > 0) {
 487                 snprintf(roomname, sizeof roomname, "%010ld.%s", im->usernums[0], PAGELOGROOM);
 488                 CtdlCreateRoom(roomname, 5, "", 0, 1, 1, VIEW_BBS);
 489                 CtdlSaveMsgPointerInRoom(roomname, msgnum, 0, NULL);
 490         }
 491
 492         /* Finally, if we're logging instant messages globally, do that now. */
 493         if (!IsEmptyStr(CtdlGetConfigStr("c_logpages"))) {
 494                 CtdlCreateRoom(CtdlGetConfigStr("c_logpages"), 3, "", 0, 1, 1, VIEW_BBS);
 495                 CtdlSaveMsgPointerInRoom(CtdlGetConfigStr("c_logpages"), msgnum, 0, NULL);
 496         }
 497
 498 }
 499
 500 /*
 501  * Locate instant message conversations which have gone idle
 502  * (or, if the server is shutting down, locate *all* conversations)
 503  * and flush them to disk (in the participants' log rooms, etc.)
 504  */
 505 void flush_conversations_to_disk(time_t if_older_than) {
 506
 507         struct imlog *flush_these = NULL;
 508         struct imlog *dont_flush_these = NULL;
 509         struct imlog *imptr = NULL;
 510         struct CitContext *nptr;
 511         int nContexts, i;
 512
 513         nptr = CtdlGetContextArray(&nContexts) ;        /* Make a copy of the current wholist */
 514
 515         begin_critical_section(S_IM_LOGS);
 516         while (imlist)
 517         {
 518                 imptr = imlist;
 519                 imlist = imlist->next;
 520
 521                 /* For a two party conversation, if one party has logged out, force flush. */
 522                 if (nptr) {
 523                         int user0_is_still_online = 0;
 524                         int user1_is_still_online = 0;
 525                         for (i=0; i<nContexts; i++)  {
 526                                 if (nptr[i].user.usernum == imptr->usernums[0]) ++user0_is_still_online;
 527                                 if (nptr[i].user.usernum == imptr->usernums[1]) ++user1_is_still_online;
 528                         }
 529                         if (imptr->usernums[0] != imptr->usernums[1]) {         /* two party conversation */
 530                                 if ((!user0_is_still_online) || (!user1_is_still_online)) {
 531                                         imptr->lastmsg = 0L;    /* force flush */
 532                                 }
 533                         }
 534                         else {          /* one party conversation (yes, people do IM themselves) */
 535                                 if (!user0_is_still_online) {
 536                                         imptr->lastmsg = 0L;    /* force flush */
 537                                 }
 538                         }
 539                 }
 540
 541                 /* Now test this conversation to see if it qualifies for flushing. */
 542                 if ((time(NULL) - imptr->lastmsg) > if_older_than)
 543                 {
 544                         /* This conversation qualifies.  Move it to the list of ones to flush. */
 545                         imptr->next = flush_these;
 546                         flush_these = imptr;
 547                 }
 548                 else  {
 549                         /* Move it to the list of ones not to flush. */
 550                         imptr->next = dont_flush_these;
 551                         dont_flush_these = imptr;
 552                 }
 553         }
 554         imlist = dont_flush_these;
 555         end_critical_section(S_IM_LOGS);
 556         free(nptr);
 557
 558         /* We are now outside of the critical section, and we are the only thread holding a
 559          * pointer to a linked list of conversations to be flushed to disk.
 560          */
 561         while (flush_these) {
 562
 563                 flush_individual_conversation(flush_these);     /* This will free the string buffer */
 564                 imptr = flush_these;
 565                 flush_these = flush_these->next;
 566                 free(imptr);
 567         }
 568 }
 569
 570
 571
 572 void instmsg_timer(void) {
 573         flush_conversations_to_disk(300);       /* Anything that hasn't peeped in more than 5 minutes */
 574 }
 575
 576 void instmsg_shutdown(void) {
 577         flush_conversations_to_disk(0);         /* Get it ALL onto disk NOW. */
 578 }
 579
 580 CTDL_MODULE_INIT(instmsg)
 581 {
 582         if (!threading)
 583         {
 584                 CtdlRegisterProtoHook(cmd_gexp, "GEXP", "Get instant messages");
 585                 CtdlRegisterProtoHook(cmd_sexp, "SEXP", "Send an instant message");
 586                 CtdlRegisterProtoHook(cmd_dexp, "DEXP", "Disable instant messages");
 587                 CtdlRegisterProtoHook(cmd_reqt, "REQT", "Request client termination");
 588                 CtdlRegisterSessionHook(cmd_gexp_async, EVT_ASYNC, PRIO_ASYNC + 1);
 589                 CtdlRegisterSessionHook(delete_instant_messages, EVT_STOP, PRIO_STOP + 1);
 590                 CtdlRegisterXmsgHook(send_instant_message, XMSG_PRI_LOCAL);
 591                 CtdlRegisterSessionHook(instmsg_timer, EVT_TIMER, PRIO_CLEANUP + 400);
 592                 CtdlRegisterSessionHook(instmsg_shutdown, EVT_SHUTDOWN, PRIO_SHUTDOWN + 10);
 593         }
 594
 595         /* return our module name for the log */
 596         return "instmsg";
 597 }