2 * Server-side module for Wiki rooms. This handles things like version control.
4 * Copyright (c) 2009-2020 by the citadel.org team
6 * This program is open source software. You can redistribute it and/or
7 * modify it under the terms of the GNU General Public License, version 3.
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.
24 #include <sys/types.h>
26 #if TIME_WITH_SYS_TIME
27 # include <sys/time.h>
31 # include <sys/time.h>
40 #include <libcitadel.h>
43 #include "citserver.h"
51 #include "euidindex.h"
52 #include "ctdl_module.h"
55 * Data passed back and forth between wiki_rev() and its MIME parser callback
57 struct HistoryEraserCallBackData {
58 char *tempfilename; /* name of temp file being patched */
59 char *stop_when; /* stop when we hit this uuid */
60 int done; /* set to nonzero when we're done patching */
64 * Name of the temporary room we create to store old revisions when someone requests them.
65 * We put it in an invalid namespace so the DAP cleans up after us later.
67 char *wwm = "9999999999.WikiWaybackMachine";
70 * Before allowing a wiki page save to execute, we have to perform version control.
71 * This involves fetching the old version of the page if it exists.
73 int wiki_upload_beforesave(struct CtdlMessage *msg, recptypes *recp) {
74 struct CitContext *CCC = CC;
75 long old_msgnum = (-1L);
76 struct CtdlMessage *old_msg = NULL;
77 long history_msgnum = (-1L);
78 struct CtdlMessage *history_msg = NULL;
79 char diff_old_filename[PATH_MAX];
80 char diff_new_filename[PATH_MAX];
81 char diff_out_filename[PATH_MAX];
82 char diff_cmd[PATH_MAX];
85 char history_page[1024];
86 long history_page_len;
88 char prefixed_boundary[258];
91 size_t diffbuf_len = 0;
96 if (!CCC->logged_in) return(0); /* Only do this if logged in. */
98 /* Is this a room with a Wiki in it, don't run this hook. */
99 if ((CCC->room.QRdefaultview != VIEW_WIKI) &&
100 (CCC->room.QRdefaultview != VIEW_WIKIMD)) {
104 /* If this isn't a MIME message, don't bother. */
105 if (msg->cm_format_type != 4) return(0);
107 /* If there's no EUID we can't do this. Reject the post. */
108 if (CM_IsEmpty(msg, eExclusiveID)) return(1);
110 newmsgid = get_new_message_number();
111 msgidbuf = NewStrBuf();
112 StrBufPrintf(msgidbuf, "%08lX-%08lX@%s/%s",
113 (long unsigned int) time(NULL),
114 (long unsigned int) newmsgid,
115 CtdlGetConfigStr("c_fqdn"),
116 msg->cm_fields[eExclusiveID]
119 CM_SetAsFieldSB(msg, emessageId, &msgidbuf);
121 history_page_len = snprintf(history_page, sizeof history_page,
122 "%s_HISTORY_", msg->cm_fields[eExclusiveID]);
124 /* Make sure we're saving a real wiki page rather than a wiki history page.
125 * This is important in order to avoid recursing infinitely into this hook.
127 if ( (msg->cm_lengths[eExclusiveID] >= 9)
128 && (!strcasecmp(&msg->cm_fields[eExclusiveID][msg->cm_lengths[eExclusiveID]-9], "_HISTORY_"))
130 syslog(LOG_DEBUG, "History page not being historied\n");
134 /* If there's no message text, obviously this is all b0rken and shouldn't happen at all */
135 if (CM_IsEmpty(msg, eMesageText)) return(0);
137 /* Set the message subject identical to the page name */
138 CM_CopyField(msg, eMsgSubject, eExclusiveID);
140 /* See if we can retrieve the previous version. */
141 old_msgnum = CtdlLocateMessageByEuid(msg->cm_fields[eExclusiveID], &CCC->room);
142 if (old_msgnum > 0L) {
143 old_msg = CtdlFetchMessage(old_msgnum, 1);
149 if ((old_msg != NULL) && (CM_IsEmpty(old_msg, eMesageText))) { /* old version is corrupt? */
154 /* If no changes were made, don't bother saving it again */
155 if ((old_msg != NULL) && (!strcmp(msg->cm_fields[eMesageText], old_msg->cm_fields[eMesageText]))) {
163 CtdlMakeTempFileName(diff_old_filename, sizeof diff_old_filename);
164 CtdlMakeTempFileName(diff_new_filename, sizeof diff_new_filename);
165 CtdlMakeTempFileName(diff_out_filename, sizeof diff_out_filename);
167 if (old_msg != NULL) {
168 fp = fopen(diff_old_filename, "w");
169 rv = fwrite(old_msg->cm_fields[eMesageText], old_msg->cm_lengths[eMesageText], 1, fp);
174 fp = fopen(diff_new_filename, "w");
175 rv = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
178 snprintf(diff_cmd, sizeof diff_cmd,
179 DIFF " -u %s %s >%s",
181 ((old_msg != NULL) ? diff_old_filename : "/dev/null"),
184 syslog(LOG_DEBUG, "diff cmd: %s", diff_cmd);
185 rv = system(diff_cmd);
186 syslog(LOG_DEBUG, "diff cmd returned %d", rv);
190 fp = fopen(diff_out_filename, "r");
192 fp = fopen("/dev/null", "r");
195 fseek(fp, 0L, SEEK_END);
196 diffbuf_len = ftell(fp);
197 fseek(fp, 0L, SEEK_SET);
198 diffbuf = malloc(diffbuf_len + 1);
199 fread(diffbuf, diffbuf_len, 1, fp);
200 diffbuf[diffbuf_len] = '\0';
204 syslog(LOG_DEBUG, "diff length is "SIZE_T_FMT" bytes", diffbuf_len);
206 unlink(diff_old_filename);
207 unlink(diff_new_filename);
208 unlink(diff_out_filename);
210 /* Determine whether this was a bogus (empty) edit */
211 if ((diffbuf_len = 0) && (diffbuf != NULL)) {
215 if (diffbuf == NULL) {
216 return(1); /* No changes at all? Abandon the post entirely! */
219 /* Now look for the existing edit history */
221 history_msgnum = CtdlLocateMessageByEuid(history_page, &CCC->room);
223 if (history_msgnum > 0L) {
224 history_msg = CtdlFetchMessage(history_msgnum, 1);
227 /* Create a new history message if necessary */
228 if (history_msg == NULL) {
232 history_msg = malloc(sizeof(struct CtdlMessage));
233 memset(history_msg, 0, sizeof(struct CtdlMessage));
234 history_msg->cm_magic = CTDLMESSAGE_MAGIC;
235 history_msg->cm_anon_type = MES_NORMAL;
236 history_msg->cm_format_type = FMT_RFC822;
237 CM_SetField(history_msg, eAuthor, HKEY("Citadel"));
238 if (!IsEmptyStr(CCC->room.QRname)){
239 CM_SetField(history_msg, eRecipient, CCC->room.QRname, strlen(CCC->room.QRname));
241 CM_SetField(history_msg, eExclusiveID, history_page, history_page_len);
242 CM_SetField(history_msg, eMsgSubject, history_page, history_page_len);
243 CM_SetField(history_msg, eSuppressIdx, HKEY("1")); /* suppress full text indexing */
244 snprintf(boundary, sizeof boundary, "Citadel--Multipart--%04x--%08lx", getpid(), time(NULL));
245 buf = (char*) malloc(1024);
246 len = snprintf(buf, 1024,
247 "Content-type: multipart/mixed; boundary=\"%s\"\n\n"
248 "This is a Citadel wiki history encoded as multipart MIME.\n"
249 "Each part is comprised of a diff script representing one change set.\n"
254 CM_SetAsField(history_msg, eMesageText, &buf, len);
257 /* Update the history message (regardless of whether it's new or existing) */
259 /* Remove the Message-ID from the old version of the history message. This will cause a brand
260 * new one to be generated, avoiding an uninitentional hit of the loop zapper when we replicate.
262 CM_FlushField(history_msg, emessageId);
264 /* Figure out the boundary string. We do this even when we generated the
265 * boundary string in the above code, just to be safe and consistent.
269 ptr = history_msg->cm_fields[eMesageText];
271 ptr = memreadline(ptr, buf, sizeof buf);
274 if (!IsEmptyStr(buf) && (!strncasecmp(buf, "Content-type:", 13))) {
276 (bmstrcasestr(buf, "multipart") != NULL)
277 && (bmstrcasestr(buf, "boundary=") != NULL)
279 safestrncpy(boundary, bmstrcasestr(buf, "\""), sizeof boundary);
281 qu = strchr(boundary, '\"');
283 strcpy(boundary, ++qu);
285 qu = strchr(boundary, '\"');
292 } while ( (IsEmptyStr(boundary)) && (*ptr != 0) );
295 * Now look for the first boundary. That is where we need to insert our fun.
297 if (!IsEmptyStr(boundary)) {
300 time_t Now = time(NULL);
302 snprintf(prefixed_boundary, sizeof(prefixed_boundary), "--%s", boundary);
304 CM_GetAsField(history_msg, eMesageText, &MsgText, &MsgTextLen);
306 ptr = bmstrcasestr(MsgText, prefixed_boundary);
312 char encoded_memo[1024];
314 NewMsgText = NewStrBufPlain(NULL, MsgTextLen + diffbuf_len + 1024);
317 memolen = snprintf(memo, sizeof(memo), "%s|%ld|%s|%s",
321 CtdlGetConfigStr("c_nodename"));
323 memolen = CtdlEncodeBase64(encoded_memo, memo, memolen, 0);
325 StrBufAppendBufPlain(NewMsgText, HKEY("--"), 0);
326 StrBufAppendBufPlain(NewMsgText, boundary, -1, 0);
327 StrBufAppendBufPlain(
330 "Content-type: text/plain\n"
331 "Content-Disposition: inline; filename=\""), 0);
333 StrBufAppendBufPlain(NewMsgText, encoded_memo, memolen, 0);
335 StrBufAppendBufPlain(
338 "Content-Transfer-Encoding: 8bit\n"
341 StrBufAppendBufPlain(NewMsgText, diffbuf, diffbuf_len, 0);
342 StrBufAppendBufPlain(NewMsgText, HKEY("\n"), 0);
344 StrBufAppendBufPlain(NewMsgText, ptr, MsgTextLen - (ptr - MsgText), 0);
346 CM_SetAsFieldSB(history_msg, eMesageText, &NewMsgText);
350 CM_SetAsField(history_msg, eMesageText, &MsgText, MsgTextLen);
353 CM_SetFieldLONG(history_msg, eTimestamp, Now);
355 CtdlSubmitMsg(history_msg, NULL, "");
358 syslog(LOG_ALERT, "Empty boundary string in history message. No history!\n");
362 CM_Free(history_msg);
368 * MIME Parser callback for wiki_history()
370 * The "filename" field will contain a memo field. All we have to do is decode
371 * the base64 and output it. The data is already in a delimited format suitable
372 * for our client protocol.
374 void wiki_history_callback(char *name, char *filename, char *partnum, char *disp,
375 void *content, char *cbtype, char *cbcharset, size_t length,
376 char *encoding, char *cbid, void *cbuserdata)
380 CtdlDecodeBase64(memo, filename, strlen(filename));
381 cprintf("%s\n", memo);
386 * Fetch a list of revisions for a particular wiki page
388 void wiki_history(char *pagename) {
390 char history_page_name[270];
392 struct CtdlMessage *msg;
394 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
396 if (r == om_not_logged_in) {
397 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
400 cprintf("%d An unknown error has occurred.\n", ERROR);
405 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
406 msgnum = CtdlLocateMessageByEuid(history_page_name, &CC->room);
408 msg = CtdlFetchMessage(msgnum, 1);
414 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
420 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
425 cprintf("%d Revision history for '%s'\n", LISTING_FOLLOWS, pagename);
426 mime_parser(CM_RANGE(msg, eMesageText), *wiki_history_callback, NULL, NULL, NULL, 0);
434 * MIME Parser callback for wiki_rev()
436 * The "filename" field will contain a memo field, which includes (among other things)
437 * the uuid of this revision. After we hit the desired revision, we stop processing.
439 * The "content" filed will contain "diff" output suitable for applying via "patch"
440 * to our temporary file.
442 void wiki_rev_callback(char *name, char *filename, char *partnum, char *disp,
443 void *content, char *cbtype, char *cbcharset, size_t length,
444 char *encoding, char *cbid, void *cbuserdata)
446 struct HistoryEraserCallBackData *hecbd = (struct HistoryEraserCallBackData *)cbuserdata;
453 /* Did a previous callback already indicate that we've reached our target uuid?
454 * If so, don't process anything else.
460 CtdlDecodeBase64(memo, filename, strlen(filename));
461 extract_token(this_rev, memo, 0, '|', sizeof this_rev);
464 /* Perform the patch */
465 fp = popen(PATCH " -f -s -p0 -r /dev/null >/dev/null 2>/dev/null", "w");
467 /* Replace the filenames in the patch with the tempfilename we're actually tweaking */
468 fprintf(fp, "--- %s\n", hecbd->tempfilename);
469 fprintf(fp, "+++ %s\n", hecbd->tempfilename);
471 ptr = (char *)content;
475 ptr = memreadline(ptr, buf, sizeof buf);
478 /* skip the first two lines; they contain bogus filenames */
481 fprintf(fp, "%s\n", buf);
484 } while ((*ptr != 0) && (ptr < ((char*)content + length)));
485 if (pclose(fp) != 0) {
486 syslog(LOG_ERR, "pclose() returned an error - patch failed\n");
490 if (!strcasecmp(this_rev, hecbd->stop_when)) {
491 /* Found our target rev. Tell any subsequent callbacks to suppress processing. */
492 syslog(LOG_DEBUG, "Target revision has been reached -- stop patching.\n");
499 * Fetch a specific revision of a wiki page. The "operation" string may be set to "fetch" in order
500 * to simply fetch the desired revision and store it in a temporary location for viewing, or "revert"
501 * to revert the currently active page to that revision.
503 void wiki_rev(char *pagename, char *rev, char *operation)
505 struct CitContext *CCC = CC;
507 char history_page_name[270];
510 struct CtdlMessage *msg;
512 struct HistoryEraserCallBackData hecbd;
516 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
518 if (r == om_not_logged_in) {
519 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
522 cprintf("%d An unknown error has occurred.\n", ERROR);
527 if (!strcasecmp(operation, "revert")) {
528 r = CtdlDoIHavePermissionToPostInThisRoom(temp, sizeof temp, NULL, POST_LOGGED_IN, 0);
530 cprintf("%d %s\n", r, temp);
535 /* Begin by fetching the current version of the page. We're going to patch
536 * backwards through the diffs until we get the one we want.
538 msgnum = CtdlLocateMessageByEuid(pagename, &CCC->room);
540 msg = CtdlFetchMessage(msgnum, 1);
546 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
552 cprintf("%d Page '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
556 /* Output it to a temporary file */
558 CtdlMakeTempFileName(temp, sizeof temp);
559 fp = fopen(temp, "w");
561 r = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
565 syslog(LOG_ERR, "%s: %m", temp);
569 /* Get the revision history */
571 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
572 msgnum = CtdlLocateMessageByEuid(history_page_name, &CCC->room);
574 msg = CtdlFetchMessage(msgnum, 1);
580 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
586 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
590 /* Start patching backwards (newest to oldest) through the revision history until we
591 * hit the revision uuid requested by the user. (The callback will perform each one.)
594 memset(&hecbd, 0, sizeof(struct HistoryEraserCallBackData));
595 hecbd.tempfilename = temp;
596 hecbd.stop_when = rev;
597 striplt(hecbd.stop_when);
599 mime_parser(CM_RANGE(msg, eMesageText), *wiki_rev_callback, NULL, NULL, (void *)&hecbd, 0);
602 /* Were we successful? */
603 if (hecbd.done == 0) {
604 cprintf("%d Revision '%s' of page '%s' was not found.\n",
605 ERROR + MESSAGE_NOT_FOUND, rev, pagename
609 /* We have the desired revision on disk. Now do something with it. */
611 else if ( (!strcasecmp(operation, "fetch")) || (!strcasecmp(operation, "revert")) ) {
612 msg = malloc(sizeof(struct CtdlMessage));
613 memset(msg, 0, sizeof(struct CtdlMessage));
614 msg->cm_magic = CTDLMESSAGE_MAGIC;
615 msg->cm_anon_type = MES_NORMAL;
616 msg->cm_format_type = FMT_RFC822;
617 fp = fopen(temp, "r");
620 fseek(fp, 0L, SEEK_END);
622 fseek(fp, 0L, SEEK_SET);
623 msgbuf = malloc(len + 1);
624 rv = fread(msgbuf, len, 1, fp);
625 syslog(LOG_DEBUG, "did %d blocks of %ld bytes\n", rv, len);
627 CM_SetAsField(msg, eMesageText, &msgbuf, len);
633 else if (!strcasecmp(operation, "fetch")) {
634 CM_SetField(msg, eAuthor, HKEY("Citadel"));
635 CtdlCreateRoom(wwm, 5, "", 0, 1, 1, VIEW_BBS); /* Not an error if already exists */
636 msgnum = CtdlSubmitMsg(msg, NULL, wwm); /* Store the revision here */
639 * WARNING: VILE SLEAZY HACK
640 * This will avoid the 'message xxx is not in this room' security error,
641 * but only if the client fetches the message we just generated immediately
642 * without first trying to perform other fetch operations.
644 if (CCC->cached_msglist != NULL) {
645 free(CCC->cached_msglist);
646 CCC->cached_msglist = NULL;
647 CCC->cached_num_msgs = 0;
649 CCC->cached_msglist = malloc(sizeof(long));
650 if (CCC->cached_msglist != NULL) {
651 CCC->cached_num_msgs = 1;
652 CCC->cached_msglist[0] = msgnum;
656 else if (!strcasecmp(operation, "revert")) {
657 CM_SetFieldLONG(msg, eTimestamp, time(NULL));
658 if (!IsEmptyStr(CCC->user.fullname)) {
659 CM_SetField(msg, eAuthor, CCC->user.fullname, strlen(CCC->user.fullname));
662 if (!IsEmptyStr(CCC->cs_inet_email)) {
663 CM_SetField(msg, erFc822Addr, CCC->cs_inet_email, strlen(CCC->cs_inet_email));
666 if (!IsEmptyStr(CCC->room.QRname)) {
667 CM_SetField(msg, eOriginalRoom, CCC->room.QRname, strlen(CCC->room.QRname));
670 if (!IsEmptyStr(pagename)) {
671 CM_SetField(msg, eExclusiveID, pagename, strlen(pagename));
673 msgnum = CtdlSubmitMsg(msg, NULL, ""); /* Replace the current revision */
676 /* Theoretically it is impossible to get here, but throw an error anyway */
681 cprintf("%d %ld\n", CIT_OK, msgnum); /* Give the client a msgnum */
684 cprintf("%d Error %ld has occurred.\n", ERROR+INTERNAL_ERROR, msgnum);
688 /* We did all this work for nothing. Express anguish to the caller. */
690 cprintf("%d An unknown operation was requested.\n", ERROR+CMD_NOT_SUPPORTED);
700 * commands related to wiki management
702 void cmd_wiki(char *argbuf) {
708 extract_token(subcmd, argbuf, 0, '|', sizeof subcmd);
710 if (!strcasecmp(subcmd, "history")) {
711 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
712 wiki_history(pagename);
716 if (!strcasecmp(subcmd, "rev")) {
717 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
718 extract_token(rev, argbuf, 2, '|', sizeof rev);
719 extract_token(operation, argbuf, 3, '|', sizeof operation);
720 wiki_rev(pagename, rev, operation);
724 cprintf("%d Invalid subcommand\n", ERROR + CMD_NOT_SUPPORTED);
730 * Module initialization
732 CTDL_MODULE_INIT(wiki)
736 CtdlRegisterMessageHook(wiki_upload_beforesave, EVT_BEFORESAVE);
737 CtdlRegisterProtoHook(cmd_wiki, "WIKI", "Commands related to Wiki management");
740 /* return our module name for the log */