citadel/modules/wiki/serv_wiki.c

   1 /*
   2  * $Id$
   3  *
   4  * Server-side module for Wiki rooms.  This will handle things like version control.
   5  *
   6  * Copyright (c) 2009 by the citadel.org team
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 3 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #include "sysdep.h"
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <stdio.h>
  27 #include <fcntl.h>
  28 #include <signal.h>
  29 #include <pwd.h>
  30 #include <errno.h>
  31 #include <ctype.h>
  32 #include <sys/types.h>
  33
  34 #if TIME_WITH_SYS_TIME
  35 # include <sys/time.h>
  36 # include <time.h>
  37 #else
  38 # if HAVE_SYS_TIME_H
  39 #  include <sys/time.h>
  40 # else
  41 #  include <time.h>
  42 # endif
  43 #endif
  44
  45 #include <sys/wait.h>
  46 #include <string.h>
  47 #include <limits.h>
  48 #include <libcitadel.h>
  49 #include "citadel.h"
  50 #include "server.h"
  51 #include "citserver.h"
  52 #include "support.h"
  53 #include "config.h"
  54 #include "control.h"
  55 #include "user_ops.h"
  56 #include "policy.h"
  57 #include "database.h"
  58 #include "msgbase.h"
  59 #include "euidindex.h"
  60 #include "ctdl_module.h"
  61
  62 /*
  63  * Before allowing a wiki page save to execute, we have to perform version control.
  64  * This involves fetching the old version of the page if it exists.
  65  */
  66 int wiki_upload_beforesave(struct CtdlMessage *msg) {
  67         struct CitContext *CCC = CC;
  68         long old_msgnum = (-1L);
  69         struct CtdlMessage *old_msg = NULL;
  70         long history_msgnum = (-1L);
  71         struct CtdlMessage *history_msg = NULL;
  72         char diff_old_filename[PATH_MAX];
  73         char diff_new_filename[PATH_MAX];
  74         char diff_cmd[PATH_MAX];
  75         FILE *fp;
  76         int rv;
  77         char history_page[1024];
  78         char boundary[256];
  79         char prefixed_boundary[258];
  80         char buf[1024];
  81         int nbytes = 0;
  82         char *diffbuf = NULL;
  83         size_t diffbuf_len = 0;
  84         char *ptr = NULL;
  85
  86         if (!CCC->logged_in) return(0); /* Only do this if logged in. */
  87
  88         /* Is this a room with a Wiki in it, don't run this hook. */
  89         if (CCC->room.QRdefaultview != VIEW_WIKI) {
  90                 return(0);
  91         }
  92
  93         /* If this isn't a MIME message, don't bother. */
  94         if (msg->cm_format_type != 4) return(0);
  95
  96         /* If there's no EUID we can't do this. */
  97         if (msg->cm_fields['E'] == NULL) return(0);
  98         snprintf(history_page, sizeof history_page, "%s_HISTORY_", msg->cm_fields['E']);
  99
 100         /* Make sure we're saving a real wiki page rather than a wiki history page.
 101          * This is important in order to avoid recursing infinitely into this hook.
 102          */
 103         if (    (strlen(msg->cm_fields['E']) >= 9)
 104                 && (!strcasecmp(&msg->cm_fields['E'][strlen(msg->cm_fields['E'])-9], "_HISTORY_"))
 105         ) {
 106                 CtdlLogPrintf(CTDL_DEBUG, "History page not being historied\n");
 107                 return(0);
 108         }
 109
 110         /* If there's no message text, obviously this is all b0rken and shouldn't happen at all */
 111         if (msg->cm_fields['M'] == NULL) return(0);
 112
 113         /* See if we can retrieve the previous version. */
 114         old_msgnum = locate_message_by_euid(msg->cm_fields['E'], &CCC->room);
 115         if (old_msgnum > 0L) {
 116                 old_msg = CtdlFetchMessage(old_msgnum, 1);
 117         }
 118         else {
 119                 old_msg = NULL;
 120         }
 121
 122         if ((old_msg != NULL) && (old_msg->cm_fields['M'] == NULL)) {   /* old version is corrupt? */
 123                 CtdlFreeMessage(old_msg);
 124                 old_msg = NULL;
 125         }
 126
 127         /* If no changes were made, don't bother saving it again */
 128         if ((old_msg != NULL) && (!strcmp(msg->cm_fields['M'], old_msg->cm_fields['M']))) {
 129                 CtdlFreeMessage(old_msg);
 130                 return(1);
 131         }
 132
 133         /*
 134          * Generate diffs
 135          */
 136         CtdlMakeTempFileName(diff_old_filename, sizeof diff_old_filename);
 137         CtdlMakeTempFileName(diff_new_filename, sizeof diff_new_filename);
 138
 139         if (old_msg != NULL) {
 140                 fp = fopen(diff_old_filename, "w");
 141                 rv = fwrite(old_msg->cm_fields['M'], strlen(old_msg->cm_fields['M']), 1, fp);
 142                 fclose(fp);
 143                 CtdlFreeMessage(old_msg);
 144         }
 145
 146         fp = fopen(diff_new_filename, "w");
 147         rv = fwrite(msg->cm_fields['M'], strlen(msg->cm_fields['M']), 1, fp);
 148         fclose(fp);
 149
 150         diffbuf_len = 0;
 151         diffbuf = NULL;
 152         snprintf(diff_cmd, sizeof diff_cmd,
 153                 "diff -u %s %s",
 154                 diff_new_filename,
 155                 ((old_msg != NULL) ? diff_old_filename : "/dev/null")
 156         );
 157         fp = popen(diff_cmd, "r");
 158         if (fp != NULL) {
 159                 do {
 160                         diffbuf = realloc(diffbuf, diffbuf_len + 1025);
 161                         nbytes = fread(&diffbuf[diffbuf_len], 1, 1024, fp);
 162                         diffbuf_len += nbytes;
 163                 } while (nbytes == 1024);
 164                 diffbuf[diffbuf_len] = 0;
 165                 pclose(fp);
 166         }
 167         CtdlLogPrintf(CTDL_DEBUG, "diff length is %d bytes\n", diffbuf_len);
 168
 169         unlink(diff_old_filename);
 170         unlink(diff_new_filename);
 171
 172         /* Determine whether this was a bogus (empty) edit */
 173         if ((diffbuf_len = 0) && (diffbuf != NULL)) {
 174                 free(diffbuf);
 175                 diffbuf = NULL;
 176         }
 177         if (diffbuf == NULL) {
 178                 return(1);              /* No changes at all?  Abandon the post entirely! */
 179         }
 180
 181         /* Now look for the existing edit history */
 182
 183         history_msgnum = locate_message_by_euid(history_page, &CCC->room);
 184         history_msg = NULL;
 185         if (history_msgnum > 0L) {
 186                 history_msg = CtdlFetchMessage(history_msgnum, 1);
 187         }
 188
 189         /* Create a new history message if necessary */
 190         if (history_msg == NULL) {
 191                 history_msg = malloc(sizeof(struct CtdlMessage));
 192                 memset(history_msg, 0, sizeof(struct CtdlMessage));
 193                 history_msg->cm_magic = CTDLMESSAGE_MAGIC;
 194                 history_msg->cm_anon_type = MES_NORMAL;
 195                 history_msg->cm_format_type = FMT_RFC822;
 196                 history_msg->cm_fields['A'] = strdup("Citadel");
 197                 history_msg->cm_fields['R'] = strdup(CCC->room.QRname);
 198                 history_msg->cm_fields['E'] = strdup(history_page);
 199                 history_msg->cm_fields['U'] = strdup(history_page);
 200                 snprintf(boundary, sizeof boundary, "Citadel--Multipart--%04x--%08lx", getpid(), time(NULL));
 201                 history_msg->cm_fields['M'] = malloc(1024);
 202                 snprintf(history_msg->cm_fields['M'], 1024,
 203                         "Content-type: multipart/mixed; boundary=\"%s\"\n\n"
 204                         "This is a Citadel wiki history encoded as multipart MIME.\n"
 205                         "Each part is comprised of a diff script representing one change set.\n"
 206                         "\n"
 207                         "--%s--\n"
 208                         ,
 209                         boundary, boundary
 210                 );
 211         }
 212
 213         /* Update the history message (regardless of whether it's new or existing) */
 214
 215         /* First, figure out the boundary string.  We do this even when we generated the
 216          * boundary string in the above code, just to be safe and consistent.
 217          */
 218         strcpy(boundary, "");
 219
 220         ptr = history_msg->cm_fields['M'];
 221         do {
 222                 ptr = memreadline(ptr, buf, sizeof buf);
 223                 if (*ptr != 0) {
 224                         striplt(buf);
 225                         if (!IsEmptyStr(buf) && (!strncasecmp(buf, "Content-type:", 13))) {
 226                                 if (
 227                                         (bmstrcasestr(buf, "multipart") != NULL)
 228                                         && (bmstrcasestr(buf, "boundary=") != NULL)
 229                                 ) {
 230                                         safestrncpy(boundary, bmstrcasestr(buf, "\""), sizeof boundary);
 231                                         char *qu;
 232                                         qu = strchr(boundary, '\"');
 233                                         if (qu) {
 234                                                 strcpy(boundary, ++qu);
 235                                         }
 236                                         qu = strchr(boundary, '\"');
 237                                         if (qu) {
 238                                                 *qu = 0;
 239                                         }
 240                                 }
 241                         }
 242                 }
 243         } while ( (IsEmptyStr(boundary)) && (*ptr != 0) );
 244
 245         /* Now look for the first boundary.  That is where we need to insert our fun.
 246          */
 247         if (!IsEmptyStr(boundary)) {
 248                 snprintf(prefixed_boundary, sizeof prefixed_boundary, "--%s", boundary);
 249                 history_msg->cm_fields['M'] = realloc(history_msg->cm_fields['M'],
 250                         strlen(history_msg->cm_fields['M']) + strlen(diffbuf) + 1024
 251                 );
 252                 ptr = bmstrcasestr(history_msg->cm_fields['M'], prefixed_boundary);
 253                 if (ptr != NULL) {
 254                         char *the_rest_of_it = strdup(ptr);
 255                         char uuid[32];
 256                         char memo[512];
 257                         char encoded_memo[768];
 258                         generate_uuid(uuid);
 259                         snprintf(memo, sizeof memo, "%s|%ld|%s|%s",
 260                                 uuid,
 261                                 time(NULL),
 262                                 CCC->user.fullname,
 263                                 config.c_nodename
 264                                 /* no longer logging CCC->cs_inet_email */
 265                         );
 266                         CtdlEncodeBase64(encoded_memo, memo, strlen(memo), 0);
 267                         sprintf(ptr, "--%s\n"
 268                                         "Content-type: text/plain\n"
 269                                         "Content-Disposition: inline; filename=\"%s\"\n"
 270                                         "Content-Transfer-Encoding: 8bit\n"
 271                                         "\n"
 272                                         "%s\n"
 273                                         "%s"
 274                                         ,
 275                                 boundary,
 276                                 encoded_memo,
 277                                 diffbuf,
 278                                 the_rest_of_it
 279                         );
 280                         free(the_rest_of_it);
 281                 }
 282
 283                 history_msg->cm_fields['T'] = realloc(history_msg->cm_fields['T'], 32);
 284                 snprintf(history_msg->cm_fields['T'], 32, "%ld", time(NULL));
 285
 286                 CtdlSubmitMsg(history_msg, NULL, "", 0);
 287         }
 288         else {
 289                 CtdlLogPrintf(CTDL_ALERT, "Empty boundary string in history message.  No history!\n");
 290         }
 291
 292         free(diffbuf);
 293         free(history_msg);
 294         return(0);
 295 }
 296
 297
 298 /*
 299  * MIME Parser callback for wiki_history()
 300  *
 301  * The "filename" field will contain a memo field.  All we have to do is decode
 302  * the base64 and output it.  The data is already in a delimited format suitable
 303  * for our client protocol.
 304  */
 305 void wiki_history_callback(char *name, char *filename, char *partnum, char *disp,
 306                    void *content, char *cbtype, char *cbcharset, size_t length,
 307                    char *encoding, char *cbid, void *cbuserdata)
 308 {
 309         char memo[1024];
 310
 311         CtdlDecodeBase64(memo, filename, strlen(filename));
 312         cprintf("%s\n", memo);
 313 }
 314
 315
 316 /*
 317  * Fetch a list of revisions for a particular wiki page
 318  */
 319 void wiki_history(char *pagename) {
 320         int r;
 321         char history_page_name[270];
 322         long msgnum;
 323         struct CtdlMessage *msg;
 324
 325         r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
 326         if (r != om_ok) {
 327                 if (r == om_not_logged_in) {
 328                         cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 329                 }
 330                 else {
 331                         cprintf("%d An unknown error has occurred.\n", ERROR);
 332                 }
 333                 return;
 334         }
 335
 336         snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
 337         msgnum = locate_message_by_euid(history_page_name, &CC->room);
 338         if (msgnum > 0L) {
 339                 msg = CtdlFetchMessage(msgnum, 1);
 340         }
 341         else {
 342                 msg = NULL;
 343         }
 344
 345         if ((msg != NULL) && (msg->cm_fields['M'] == NULL)) {
 346                 CtdlFreeMessage(msg);
 347                 msg = NULL;
 348         }
 349
 350         if (msg == NULL) {
 351                 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
 352                 return;
 353         }
 354
 355
 356         cprintf("%d Revision history for '%s'\n", LISTING_FOLLOWS, pagename);
 357         mime_parser(msg->cm_fields['M'], NULL, *wiki_history_callback, NULL, NULL, NULL, 0);
 358         cprintf("000\n");
 359
 360         CtdlFreeMessage(msg);
 361         return;
 362 }
 363
 364
 365 struct HistoryEraserCallBackData {
 366         char *tempfilename;             /* name of temp file being patched */
 367         char *stop_when;                /* stop when we hit this uuid */
 368         int done;                       /* set to nonzero when we're done patching */
 369 };
 370
 371
 372
 373 /*
 374  * MIME Parser callback for wiki_rev()
 375  *
 376  * The "filename" field will contain a memo field.  All we have to do is decode
 377  * the base64 and output it.  The data is already in a delimited format suitable
 378  * for our client protocol.
 379  */
 380 void wiki_rev_callback(char *name, char *filename, char *partnum, char *disp,
 381                    void *content, char *cbtype, char *cbcharset, size_t length,
 382                    char *encoding, char *cbid, void *cbuserdata)
 383 {
 384         struct HistoryEraserCallBackData *hecbd = (struct HistoryEraserCallBackData *)cbuserdata;
 385         char memo[1024];
 386         char this_rev[256];
 387         FILE *fp;
 388         char *ptr = NULL;
 389         char buf[1024];
 390
 391         /* Did a previous callback already indicate that we've reached our target uuid?
 392          * If so, don't process anything else.
 393          */
 394         if (hecbd->done) {
 395                 return;
 396         }
 397
 398         CtdlDecodeBase64(memo, filename, strlen(filename));
 399         extract_token(this_rev, memo, 0, '|', sizeof this_rev);
 400         CtdlLogPrintf(CTDL_DEBUG, "callback found rev: %s\n", this_rev);
 401
 402         /* Perform the patch */
 403         fp = popen("patch -f -s -p0 >/dev/null 2>/dev/null", "w");
 404         if (fp) {
 405                 /* Replace the filenames in the patch with the tempfilename we're actually tweaking */
 406                 fprintf(fp, "--- %s\n", hecbd->tempfilename);
 407                 fprintf(fp, "+++ %s\n", hecbd->tempfilename);
 408
 409                 ptr = (char *)content;
 410                 int linenum = 0;
 411                 do {
 412                         ++linenum;
 413                         ptr = memreadline(ptr, buf, sizeof buf);
 414                         if (*ptr != 0) {
 415                                 if (linenum <= 2) {
 416                                         /* skip the first two lines; they contain bogus filenames */
 417                                 }
 418                                 else {
 419                                         fprintf(fp, "%s\n", buf);
 420                                 }
 421                         }
 422                 } while ((*ptr != 0) && ((int)ptr < ((int)content + length)));
 423                 pclose(fp);
 424         }
 425
 426         if (!strcasecmp(this_rev, hecbd->stop_when)) {
 427                 CtdlLogPrintf(CTDL_DEBUG, "Found our target rev.  Stopping!\n");
 428                 hecbd->done = 1;
 429         }
 430 }
 431
 432
 433 /*
 434  * Fetch a specific revision of a wiki page
 435  */
 436 void wiki_rev(char *pagename, char *rev, char *operation)
 437 {
 438         int r;
 439         char history_page_name[270];
 440         long msgnum;
 441         char temp[PATH_MAX];
 442         struct CtdlMessage *msg;
 443         FILE *fp;
 444         struct HistoryEraserCallBackData hecbd;
 445         int rv;
 446
 447         r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
 448         if (r != om_ok) {
 449                 if (r == om_not_logged_in) {
 450                         cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
 451                 }
 452                 else {
 453                         cprintf("%d An unknown error has occurred.\n", ERROR);
 454                 }
 455                 return;
 456         }
 457
 458         /* Begin by fetching the current version of the page.  We're going to patch
 459          * backwards through the diffs until we get the one we want.
 460          */
 461         msgnum = locate_message_by_euid(pagename, &CC->room);
 462         if (msgnum > 0L) {
 463                 msg = CtdlFetchMessage(msgnum, 1);
 464         }
 465         else {
 466                 msg = NULL;
 467         }
 468
 469         if ((msg != NULL) && (msg->cm_fields['M'] == NULL)) {
 470                 CtdlFreeMessage(msg);
 471                 msg = NULL;
 472         }
 473
 474         if (msg == NULL) {
 475                 cprintf("%d Page '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
 476                 return;
 477         }
 478
 479         /* Output it to a file... */
 480
 481         CtdlMakeTempFileName(temp, sizeof temp);
 482         fp = fopen(temp, "w");
 483         if (fp != NULL) {
 484                 r = fwrite(msg->cm_fields['M'], strlen(msg->cm_fields['M']), 1, fp);
 485                 fclose(fp);
 486         }
 487         else {
 488                 CtdlLogPrintf(CTDL_ALERT, "Cannot open %s: %s\n", temp, strerror(errno));
 489         }
 490         CtdlFreeMessage(msg);
 491
 492         /* Now go get the revision history and patch backwards through the diffs until
 493          * we get to the revision we want.
 494          */
 495
 496         snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
 497         msgnum = locate_message_by_euid(history_page_name, &CC->room);
 498         if (msgnum > 0L) {
 499                 msg = CtdlFetchMessage(msgnum, 1);
 500         }
 501         else {
 502                 msg = NULL;
 503         }
 504
 505         if ((msg != NULL) && (msg->cm_fields['M'] == NULL)) {
 506                 CtdlFreeMessage(msg);
 507                 msg = NULL;
 508         }
 509
 510         if (msg == NULL) {
 511                 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
 512                 return;
 513         }
 514
 515         memset(&hecbd, 0, sizeof(struct HistoryEraserCallBackData));
 516         hecbd.tempfilename = temp;
 517         hecbd.stop_when = rev;
 518
 519         mime_parser(msg->cm_fields['M'], NULL, *wiki_rev_callback, NULL, NULL, (void *)&hecbd, 0);
 520         CtdlFreeMessage(msg);
 521
 522         if (hecbd.done == 0) {
 523                 cprintf("%d Revision '%s' of page '%s' was not found.\n",
 524                         ERROR + MESSAGE_NOT_FOUND, rev, pagename
 525                 );
 526         }
 527         else if (!strcasecmp(operation, "fetch")) {
 528                 msg = malloc(sizeof(struct CtdlMessage));
 529                 memset(msg, 0, sizeof(struct CtdlMessage));
 530                 msg->cm_magic = CTDLMESSAGE_MAGIC;
 531                 msg->cm_anon_type = MES_NORMAL;
 532                 msg->cm_format_type = FMT_RFC822;
 533                 msg->cm_fields['A'] = strdup("Citadel");
 534                 fp = fopen(temp, "r");
 535                 if (fp) {
 536                         long len;
 537                         fseek(fp, 0L, SEEK_END);
 538                         len = ftell(fp);
 539                         fseek(fp, 0L, SEEK_SET);
 540                         msg->cm_fields['M'] = malloc(len + 1);
 541                         rv = fread(msg->cm_fields['M'], len, 1, fp);
 542                         msg->cm_fields['M'][len] = 0;
 543                         fclose(fp);
 544                 }
 545                 char *wwm = "9999999999.WikiWaybackMachine";
 546                 CtdlCreateRoom(wwm, 5, "", 0, 1, 1, VIEW_BBS);
 547                 msgnum = CtdlSubmitMsg(msg, NULL, wwm, 0);      /* FIXME put somewhere else */
 548                 CtdlFreeMessage(msg);
 549                 cprintf("%d %ld\n", CIT_OK, msgnum);
 550         }
 551         else if (!strcasecmp(operation, "revert")) {
 552                 cprintf("%d FIXME not finished yet, check the log to find out wtf\n", ERROR);
 553         }
 554         else {
 555                 cprintf("%d An unknown operation was requested.\n", ERROR+CMD_NOT_SUPPORTED);
 556         }
 557
 558         unlink(temp);
 559         return;
 560 }
 561
 562
 563
 564 /*
 565  * commands related to wiki management
 566  */
 567 void cmd_wiki(char *argbuf) {
 568         char subcmd[32];
 569         char pagename[256];
 570         char rev[128];
 571         char operation[16];
 572
 573         extract_token(subcmd, argbuf, 0, '|', sizeof subcmd);
 574
 575         if (!strcasecmp(subcmd, "history")) {
 576                 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
 577                 wiki_history(pagename);
 578                 return;
 579         }
 580
 581         if (!strcasecmp(subcmd, "rev")) {
 582                 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
 583                 extract_token(rev, argbuf, 2, '|', sizeof rev);
 584                 extract_token(operation, argbuf, 3, '|', sizeof operation);
 585                 wiki_rev(pagename, rev, operation);
 586                 return;
 587         }
 588
 589         cprintf("%d Invalid subcommand\n", ERROR + CMD_NOT_SUPPORTED);
 590 }
 591
 592
 593
 594 /*
 595  * Module initialization
 596  */
 597 CTDL_MODULE_INIT(wiki)
 598 {
 599         if (!threading)
 600         {
 601                 CtdlRegisterMessageHook(wiki_upload_beforesave, EVT_BEFORESAVE);
 602                 CtdlRegisterProtoHook(cmd_wiki, "WIKI", "Commands related to Wiki management");
 603         }
 604
 605         /* return our Subversion id for the Log */
 606         return "$Id$";
 607 }