2 * Server-side module for Wiki rooms. This handles things like version control.
4 * Copyright (c) 2009-2022 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.
15 #include "../../sysdep.h"
24 #include <sys/types.h>
29 #include <libcitadel.h>
30 #include "../../citadel.h"
31 #include "../../server.h"
32 #include "../../citserver.h"
33 #include "../../support.h"
34 #include "../../config.h"
35 #include "../../control.h"
36 #include "../../user_ops.h"
37 #include "../../room_ops.h"
38 #include "../../database.h"
39 #include "../../msgbase.h"
40 #include "../../euidindex.h"
41 #include "../../ctdl_module.h"
44 * Data passed back and forth between wiki_rev() and its MIME parser callback
46 struct HistoryEraserCallBackData {
47 char *tempfilename; /* name of temp file being patched */
48 char *stop_when; /* stop when we hit this uuid */
49 int done; /* set to nonzero when we're done patching */
53 * Name of the temporary room we create to store old revisions when someone requests them.
54 * We put it in an invalid namespace so the DAP cleans up after us later.
56 char *wwm = "9999999999.WikiWaybackMachine";
59 * Before allowing a wiki page save to execute, we have to perform version control.
60 * This involves fetching the old version of the page if it exists.
62 int wiki_upload_beforesave(struct CtdlMessage *msg, struct recptypes *recp) {
63 long old_msgnum = (-1L);
64 struct CtdlMessage *old_msg = NULL;
65 long history_msgnum = (-1L);
66 struct CtdlMessage *history_msg = NULL;
67 char diff_old_filename[PATH_MAX];
68 char diff_new_filename[PATH_MAX];
69 char diff_out_filename[PATH_MAX];
70 char diff_cmd[PATH_MAX];
73 char history_page[1024];
74 long history_page_len;
76 char prefixed_boundary[258];
79 size_t diffbuf_len = 0;
84 if (!CC->logged_in) return(0); /* Only do this if logged in. */
86 /* Is this a room with a Wiki in it, don't run this hook. */
87 if (CC->room.QRdefaultview != VIEW_WIKI) {
91 /* If this isn't a MIME message, don't bother. */
92 if (msg->cm_format_type != 4) return(0);
94 /* If there's no EUID we can't do this. Reject the post. */
95 if (CM_IsEmpty(msg, eExclusiveID)) return(1);
97 newmsgid = get_new_message_number();
98 msgidbuf = NewStrBuf();
99 StrBufPrintf(msgidbuf, "%08lX-%08lX@%s/%s",
100 (long unsigned int) time(NULL),
101 (long unsigned int) newmsgid,
102 CtdlGetConfigStr("c_fqdn"),
103 msg->cm_fields[eExclusiveID]
106 CM_SetAsFieldSB(msg, emessageId, &msgidbuf);
108 history_page_len = snprintf(history_page, sizeof history_page,
109 "%s_HISTORY_", msg->cm_fields[eExclusiveID]);
111 /* Make sure we're saving a real wiki page rather than a wiki history page.
112 * This is important in order to avoid recursing infinitely into this hook.
114 if ( (msg->cm_lengths[eExclusiveID] >= 9)
115 && (!strcasecmp(&msg->cm_fields[eExclusiveID][msg->cm_lengths[eExclusiveID]-9], "_HISTORY_"))
117 syslog(LOG_DEBUG, "History page not being historied\n");
121 /* If there's no message text, obviously this is all b0rken and shouldn't happen at all */
122 if (CM_IsEmpty(msg, eMesageText)) return(0);
124 /* Set the message subject identical to the page name */
125 CM_CopyField(msg, eMsgSubject, eExclusiveID);
127 /* See if we can retrieve the previous version. */
128 old_msgnum = CtdlLocateMessageByEuid(msg->cm_fields[eExclusiveID], &CC->room);
129 if (old_msgnum > 0L) {
130 old_msg = CtdlFetchMessage(old_msgnum, 1);
136 if ((old_msg != NULL) && (CM_IsEmpty(old_msg, eMesageText))) { /* old version is corrupt? */
141 /* If no changes were made, don't bother saving it again */
142 if ((old_msg != NULL) && (!strcmp(msg->cm_fields[eMesageText], old_msg->cm_fields[eMesageText]))) {
150 CtdlMakeTempFileName(diff_old_filename, sizeof diff_old_filename);
151 CtdlMakeTempFileName(diff_new_filename, sizeof diff_new_filename);
152 CtdlMakeTempFileName(diff_out_filename, sizeof diff_out_filename);
154 if (old_msg != NULL) {
155 fp = fopen(diff_old_filename, "w");
156 rv = fwrite(old_msg->cm_fields[eMesageText], old_msg->cm_lengths[eMesageText], 1, fp);
161 fp = fopen(diff_new_filename, "w");
162 rv = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
165 snprintf(diff_cmd, sizeof diff_cmd,
168 ((old_msg != NULL) ? diff_old_filename : "/dev/null"),
171 syslog(LOG_DEBUG, "diff cmd: %s", diff_cmd);
172 rv = system(diff_cmd);
173 syslog(LOG_DEBUG, "diff cmd returned %d", rv);
177 fp = fopen(diff_out_filename, "r");
179 fp = fopen("/dev/null", "r");
182 fseek(fp, 0L, SEEK_END);
183 diffbuf_len = ftell(fp);
184 fseek(fp, 0L, SEEK_SET);
185 diffbuf = malloc(diffbuf_len + 1);
186 fread(diffbuf, diffbuf_len, 1, fp);
187 diffbuf[diffbuf_len] = '\0';
191 syslog(LOG_DEBUG, "diff length is "SIZE_T_FMT" bytes", diffbuf_len);
193 unlink(diff_old_filename);
194 unlink(diff_new_filename);
195 unlink(diff_out_filename);
197 /* Determine whether this was a bogus (empty) edit */
198 if ((diffbuf_len = 0) && (diffbuf != NULL)) {
202 if (diffbuf == NULL) {
203 return(1); /* No changes at all? Abandon the post entirely! */
206 /* Now look for the existing edit history */
208 history_msgnum = CtdlLocateMessageByEuid(history_page, &CC->room);
210 if (history_msgnum > 0L) {
211 history_msg = CtdlFetchMessage(history_msgnum, 1);
214 /* Create a new history message if necessary */
215 if (history_msg == NULL) {
219 history_msg = malloc(sizeof(struct CtdlMessage));
220 memset(history_msg, 0, sizeof(struct CtdlMessage));
221 history_msg->cm_magic = CTDLMESSAGE_MAGIC;
222 history_msg->cm_anon_type = MES_NORMAL;
223 history_msg->cm_format_type = FMT_RFC822;
224 CM_SetField(history_msg, eAuthor, HKEY("Citadel"));
225 if (!IsEmptyStr(CC->room.QRname)){
226 CM_SetField(history_msg, eRecipient, CC->room.QRname, strlen(CC->room.QRname));
228 CM_SetField(history_msg, eExclusiveID, history_page, history_page_len);
229 CM_SetField(history_msg, eMsgSubject, history_page, history_page_len);
230 CM_SetField(history_msg, eSuppressIdx, HKEY("1")); /* suppress full text indexing */
231 snprintf(boundary, sizeof boundary, "Citadel--Multipart--%04x--%08lx", getpid(), time(NULL));
232 buf = (char*) malloc(1024);
233 len = snprintf(buf, 1024,
234 "Content-type: multipart/mixed; boundary=\"%s\"\n\n"
235 "This is a Citadel wiki history encoded as multipart MIME.\n"
236 "Each part is comprised of a diff script representing one change set.\n"
241 CM_SetAsField(history_msg, eMesageText, &buf, len);
244 /* Update the history message (regardless of whether it's new or existing) */
246 /* Remove the Message-ID from the old version of the history message. This will cause a brand
247 * new one to be generated, avoiding an uninitentional hit of the loop zapper when we replicate.
249 CM_FlushField(history_msg, emessageId);
251 /* Figure out the boundary string. We do this even when we generated the
252 * boundary string in the above code, just to be safe and consistent.
256 ptr = history_msg->cm_fields[eMesageText];
258 ptr = memreadline(ptr, buf, sizeof buf);
261 if (!IsEmptyStr(buf) && (!strncasecmp(buf, "Content-type:", 13))) {
263 (bmstrcasestr(buf, "multipart") != NULL)
264 && (bmstrcasestr(buf, "boundary=") != NULL)
266 safestrncpy(boundary, bmstrcasestr(buf, "\""), sizeof boundary);
268 qu = strchr(boundary, '\"');
270 strcpy(boundary, ++qu);
272 qu = strchr(boundary, '\"');
279 } while ( (IsEmptyStr(boundary)) && (*ptr != 0) );
282 * Now look for the first boundary. That is where we need to insert our fun.
284 if (!IsEmptyStr(boundary)) {
287 time_t Now = time(NULL);
289 snprintf(prefixed_boundary, sizeof(prefixed_boundary), "--%s", boundary);
291 CM_GetAsField(history_msg, eMesageText, &MsgText, &MsgTextLen);
293 ptr = bmstrcasestr(MsgText, prefixed_boundary);
299 char encoded_memo[1024];
301 NewMsgText = NewStrBufPlain(NULL, MsgTextLen + diffbuf_len + 1024);
304 memolen = snprintf(memo, sizeof(memo), "%s|%ld|%s|%s",
308 CtdlGetConfigStr("c_nodename"));
310 memolen = CtdlEncodeBase64(encoded_memo, memo, memolen, 0);
312 StrBufAppendBufPlain(NewMsgText, HKEY("--"), 0);
313 StrBufAppendBufPlain(NewMsgText, boundary, -1, 0);
314 StrBufAppendBufPlain(
317 "Content-type: text/plain\n"
318 "Content-Disposition: inline; filename=\""), 0);
320 StrBufAppendBufPlain(NewMsgText, encoded_memo, memolen, 0);
322 StrBufAppendBufPlain(
325 "Content-Transfer-Encoding: 8bit\n"
328 StrBufAppendBufPlain(NewMsgText, diffbuf, diffbuf_len, 0);
329 StrBufAppendBufPlain(NewMsgText, HKEY("\n"), 0);
331 StrBufAppendBufPlain(NewMsgText, ptr, MsgTextLen - (ptr - MsgText), 0);
333 CM_SetAsFieldSB(history_msg, eMesageText, &NewMsgText);
337 CM_SetAsField(history_msg, eMesageText, &MsgText, MsgTextLen);
340 CM_SetFieldLONG(history_msg, eTimestamp, Now);
342 CtdlSubmitMsg(history_msg, NULL, "");
345 syslog(LOG_ALERT, "Empty boundary string in history message. No history!\n");
349 CM_Free(history_msg);
355 * MIME Parser callback for wiki_history()
357 * The "filename" field will contain a memo field. All we have to do is decode
358 * the base64 and output it. The data is already in a delimited format suitable
359 * for our client protocol.
361 void wiki_history_callback(char *name, char *filename, char *partnum, char *disp,
362 void *content, char *cbtype, char *cbcharset, size_t length,
363 char *encoding, char *cbid, void *cbuserdata)
367 CtdlDecodeBase64(memo, filename, strlen(filename));
368 cprintf("%s\n", memo);
373 * Fetch a list of revisions for a particular wiki page
375 void wiki_history(char *pagename) {
377 char history_page_name[270];
379 struct CtdlMessage *msg;
381 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
383 if (r == om_not_logged_in) {
384 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
387 cprintf("%d An unknown error has occurred.\n", ERROR);
392 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
393 msgnum = CtdlLocateMessageByEuid(history_page_name, &CC->room);
395 msg = CtdlFetchMessage(msgnum, 1);
401 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
407 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
412 cprintf("%d Revision history for '%s'\n", LISTING_FOLLOWS, pagename);
413 mime_parser(CM_RANGE(msg, eMesageText), *wiki_history_callback, NULL, NULL, NULL, 0);
421 * MIME Parser callback for wiki_rev()
423 * The "filename" field will contain a memo field, which includes (among other things)
424 * the uuid of this revision. After we hit the desired revision, we stop processing.
426 * The "content" filed will contain "diff" output suitable for applying via "patch"
427 * to our temporary file.
429 void wiki_rev_callback(char *name, char *filename, char *partnum, char *disp,
430 void *content, char *cbtype, char *cbcharset, size_t length,
431 char *encoding, char *cbid, void *cbuserdata)
433 struct HistoryEraserCallBackData *hecbd = (struct HistoryEraserCallBackData *)cbuserdata;
440 /* Did a previous callback already indicate that we've reached our target uuid?
441 * If so, don't process anything else.
447 CtdlDecodeBase64(memo, filename, strlen(filename));
448 extract_token(this_rev, memo, 0, '|', sizeof this_rev);
451 /* Perform the patch */
452 fp = popen("patch -f -s -p0 -r /dev/null >/dev/null 2>/dev/null", "w");
454 /* Replace the filenames in the patch with the tempfilename we're actually tweaking */
455 fprintf(fp, "--- %s\n", hecbd->tempfilename);
456 fprintf(fp, "+++ %s\n", hecbd->tempfilename);
458 ptr = (char *)content;
462 ptr = memreadline(ptr, buf, sizeof buf);
465 /* skip the first two lines; they contain bogus filenames */
468 fprintf(fp, "%s\n", buf);
471 } while ((*ptr != 0) && (ptr < ((char*)content + length)));
472 if (pclose(fp) != 0) {
473 syslog(LOG_ERR, "pclose() returned an error - patch failed\n");
477 if (!strcasecmp(this_rev, hecbd->stop_when)) {
478 /* Found our target rev. Tell any subsequent callbacks to suppress processing. */
479 syslog(LOG_DEBUG, "Target revision has been reached -- stop patching.\n");
486 * Fetch a specific revision of a wiki page. The "operation" string may be set to "fetch" in order
487 * to simply fetch the desired revision and store it in a temporary location for viewing, or "revert"
488 * to revert the currently active page to that revision.
490 void wiki_rev(char *pagename, char *rev, char *operation)
493 char history_page_name[270];
496 struct CtdlMessage *msg;
498 struct HistoryEraserCallBackData hecbd;
502 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
504 if (r == om_not_logged_in) {
505 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
508 cprintf("%d An unknown error has occurred.\n", ERROR);
513 if (!strcasecmp(operation, "revert")) {
514 r = CtdlDoIHavePermissionToPostInThisRoom(temp, sizeof temp, POST_LOGGED_IN, 0);
516 cprintf("%d %s\n", r, temp);
521 /* Begin by fetching the current version of the page. We're going to patch
522 * backwards through the diffs until we get the one we want.
524 msgnum = CtdlLocateMessageByEuid(pagename, &CC->room);
526 msg = CtdlFetchMessage(msgnum, 1);
532 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
538 cprintf("%d Page '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
542 /* Output it to a temporary file */
544 CtdlMakeTempFileName(temp, sizeof temp);
545 fp = fopen(temp, "w");
547 r = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
551 syslog(LOG_ERR, "%s: %m", temp);
555 /* Get the revision history */
557 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
558 msgnum = CtdlLocateMessageByEuid(history_page_name, &CC->room);
560 msg = CtdlFetchMessage(msgnum, 1);
566 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
572 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
576 /* Start patching backwards (newest to oldest) through the revision history until we
577 * hit the revision uuid requested by the user. (The callback will perform each one.)
580 memset(&hecbd, 0, sizeof(struct HistoryEraserCallBackData));
581 hecbd.tempfilename = temp;
582 hecbd.stop_when = rev;
583 striplt(hecbd.stop_when);
585 mime_parser(CM_RANGE(msg, eMesageText), *wiki_rev_callback, NULL, NULL, (void *)&hecbd, 0);
588 /* Were we successful? */
589 if (hecbd.done == 0) {
590 cprintf("%d Revision '%s' of page '%s' was not found.\n",
591 ERROR + MESSAGE_NOT_FOUND, rev, pagename
595 /* We have the desired revision on disk. Now do something with it. */
597 else if ( (!strcasecmp(operation, "fetch")) || (!strcasecmp(operation, "revert")) ) {
598 msg = malloc(sizeof(struct CtdlMessage));
599 memset(msg, 0, sizeof(struct CtdlMessage));
600 msg->cm_magic = CTDLMESSAGE_MAGIC;
601 msg->cm_anon_type = MES_NORMAL;
602 msg->cm_format_type = FMT_RFC822;
603 fp = fopen(temp, "r");
606 fseek(fp, 0L, SEEK_END);
608 fseek(fp, 0L, SEEK_SET);
609 msgbuf = malloc(len + 1);
610 rv = fread(msgbuf, len, 1, fp);
611 syslog(LOG_DEBUG, "did %d blocks of %ld bytes\n", rv, len);
613 CM_SetAsField(msg, eMesageText, &msgbuf, len);
619 else if (!strcasecmp(operation, "fetch")) {
620 CM_SetField(msg, eAuthor, HKEY("Citadel"));
621 CtdlCreateRoom(wwm, 5, "", 0, 1, 1, VIEW_BBS); /* Not an error if already exists */
622 msgnum = CtdlSubmitMsg(msg, NULL, wwm); /* Store the revision here */
625 * WARNING: VILE SLEAZY HACK
626 * This will avoid the 'message xxx is not in this room' security error,
627 * but only if the client fetches the message we just generated immediately
628 * without first trying to perform other fetch operations.
630 if (CC->cached_msglist != NULL) {
631 free(CC->cached_msglist);
632 CC->cached_msglist = NULL;
633 CC->cached_num_msgs = 0;
635 CC->cached_msglist = malloc(sizeof(long));
636 if (CC->cached_msglist != NULL) {
637 CC->cached_num_msgs = 1;
638 CC->cached_msglist[0] = msgnum;
642 else if (!strcasecmp(operation, "revert")) {
643 CM_SetFieldLONG(msg, eTimestamp, time(NULL));
644 if (!IsEmptyStr(CC->user.fullname)) {
645 CM_SetField(msg, eAuthor, CC->user.fullname, strlen(CC->user.fullname));
648 if (!IsEmptyStr(CC->cs_inet_email)) {
649 CM_SetField(msg, erFc822Addr, CC->cs_inet_email, strlen(CC->cs_inet_email));
652 if (!IsEmptyStr(CC->room.QRname)) {
653 CM_SetField(msg, eOriginalRoom, CC->room.QRname, strlen(CC->room.QRname));
656 if (!IsEmptyStr(pagename)) {
657 CM_SetField(msg, eExclusiveID, pagename, strlen(pagename));
659 msgnum = CtdlSubmitMsg(msg, NULL, ""); /* Replace the current revision */
662 /* Theoretically it is impossible to get here, but throw an error anyway */
667 cprintf("%d %ld\n", CIT_OK, msgnum); /* Give the client a msgnum */
670 cprintf("%d Error %ld has occurred.\n", ERROR+INTERNAL_ERROR, msgnum);
674 /* We did all this work for nothing. Express anguish to the caller. */
676 cprintf("%d An unknown operation was requested.\n", ERROR+CMD_NOT_SUPPORTED);
686 * commands related to wiki management
688 void cmd_wiki(char *argbuf) {
694 extract_token(subcmd, argbuf, 0, '|', sizeof subcmd);
696 if (!strcasecmp(subcmd, "history")) {
697 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
698 wiki_history(pagename);
702 if (!strcasecmp(subcmd, "rev")) {
703 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
704 extract_token(rev, argbuf, 2, '|', sizeof rev);
705 extract_token(operation, argbuf, 3, '|', sizeof operation);
706 wiki_rev(pagename, rev, operation);
710 cprintf("%d Invalid subcommand\n", ERROR + CMD_NOT_SUPPORTED);
716 * Module initialization
718 char *ctdl_module_init_wiki() {
720 CtdlRegisterMessageHook(wiki_upload_beforesave, EVT_BEFORESAVE);
721 CtdlRegisterProtoHook(cmd_wiki, "WIKI", "Commands related to Wiki management");
724 /* return our module name for the log */