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>
29 #include <libcitadel.h>
32 #include "citserver.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, recptypes *recp) {
63 struct CitContext *CCC = CC;
64 long old_msgnum = (-1L);
65 struct CtdlMessage *old_msg = NULL;
66 long history_msgnum = (-1L);
67 struct CtdlMessage *history_msg = NULL;
68 char diff_old_filename[PATH_MAX];
69 char diff_new_filename[PATH_MAX];
70 char diff_out_filename[PATH_MAX];
71 char diff_cmd[PATH_MAX];
74 char history_page[1024];
75 long history_page_len;
77 char prefixed_boundary[258];
80 size_t diffbuf_len = 0;
85 if (!CCC->logged_in) return(0); /* Only do this if logged in. */
87 /* Is this a room with a Wiki in it, don't run this hook. */
88 if ((CCC->room.QRdefaultview != VIEW_WIKI) &&
89 (CCC->room.QRdefaultview != VIEW_WIKIMD)) {
93 /* If this isn't a MIME message, don't bother. */
94 if (msg->cm_format_type != 4) return(0);
96 /* If there's no EUID we can't do this. Reject the post. */
97 if (CM_IsEmpty(msg, eExclusiveID)) return(1);
99 newmsgid = get_new_message_number();
100 msgidbuf = NewStrBuf();
101 StrBufPrintf(msgidbuf, "%08lX-%08lX@%s/%s",
102 (long unsigned int) time(NULL),
103 (long unsigned int) newmsgid,
104 CtdlGetConfigStr("c_fqdn"),
105 msg->cm_fields[eExclusiveID]
108 CM_SetAsFieldSB(msg, emessageId, &msgidbuf);
110 history_page_len = snprintf(history_page, sizeof history_page,
111 "%s_HISTORY_", msg->cm_fields[eExclusiveID]);
113 /* Make sure we're saving a real wiki page rather than a wiki history page.
114 * This is important in order to avoid recursing infinitely into this hook.
116 if ( (msg->cm_lengths[eExclusiveID] >= 9)
117 && (!strcasecmp(&msg->cm_fields[eExclusiveID][msg->cm_lengths[eExclusiveID]-9], "_HISTORY_"))
119 syslog(LOG_DEBUG, "History page not being historied\n");
123 /* If there's no message text, obviously this is all b0rken and shouldn't happen at all */
124 if (CM_IsEmpty(msg, eMesageText)) return(0);
126 /* Set the message subject identical to the page name */
127 CM_CopyField(msg, eMsgSubject, eExclusiveID);
129 /* See if we can retrieve the previous version. */
130 old_msgnum = CtdlLocateMessageByEuid(msg->cm_fields[eExclusiveID], &CCC->room);
131 if (old_msgnum > 0L) {
132 old_msg = CtdlFetchMessage(old_msgnum, 1);
138 if ((old_msg != NULL) && (CM_IsEmpty(old_msg, eMesageText))) { /* old version is corrupt? */
143 /* If no changes were made, don't bother saving it again */
144 if ((old_msg != NULL) && (!strcmp(msg->cm_fields[eMesageText], old_msg->cm_fields[eMesageText]))) {
152 CtdlMakeTempFileName(diff_old_filename, sizeof diff_old_filename);
153 CtdlMakeTempFileName(diff_new_filename, sizeof diff_new_filename);
154 CtdlMakeTempFileName(diff_out_filename, sizeof diff_out_filename);
156 if (old_msg != NULL) {
157 fp = fopen(diff_old_filename, "w");
158 rv = fwrite(old_msg->cm_fields[eMesageText], old_msg->cm_lengths[eMesageText], 1, fp);
163 fp = fopen(diff_new_filename, "w");
164 rv = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
167 snprintf(diff_cmd, sizeof diff_cmd,
168 DIFF " -u %s %s >%s",
170 ((old_msg != NULL) ? diff_old_filename : "/dev/null"),
173 syslog(LOG_DEBUG, "diff cmd: %s", diff_cmd);
174 rv = system(diff_cmd);
175 syslog(LOG_DEBUG, "diff cmd returned %d", rv);
179 fp = fopen(diff_out_filename, "r");
181 fp = fopen("/dev/null", "r");
184 fseek(fp, 0L, SEEK_END);
185 diffbuf_len = ftell(fp);
186 fseek(fp, 0L, SEEK_SET);
187 diffbuf = malloc(diffbuf_len + 1);
188 fread(diffbuf, diffbuf_len, 1, fp);
189 diffbuf[diffbuf_len] = '\0';
193 syslog(LOG_DEBUG, "diff length is "SIZE_T_FMT" bytes", diffbuf_len);
195 unlink(diff_old_filename);
196 unlink(diff_new_filename);
197 unlink(diff_out_filename);
199 /* Determine whether this was a bogus (empty) edit */
200 if ((diffbuf_len = 0) && (diffbuf != NULL)) {
204 if (diffbuf == NULL) {
205 return(1); /* No changes at all? Abandon the post entirely! */
208 /* Now look for the existing edit history */
210 history_msgnum = CtdlLocateMessageByEuid(history_page, &CCC->room);
212 if (history_msgnum > 0L) {
213 history_msg = CtdlFetchMessage(history_msgnum, 1);
216 /* Create a new history message if necessary */
217 if (history_msg == NULL) {
221 history_msg = malloc(sizeof(struct CtdlMessage));
222 memset(history_msg, 0, sizeof(struct CtdlMessage));
223 history_msg->cm_magic = CTDLMESSAGE_MAGIC;
224 history_msg->cm_anon_type = MES_NORMAL;
225 history_msg->cm_format_type = FMT_RFC822;
226 CM_SetField(history_msg, eAuthor, HKEY("Citadel"));
227 if (!IsEmptyStr(CCC->room.QRname)){
228 CM_SetField(history_msg, eRecipient, CCC->room.QRname, strlen(CCC->room.QRname));
230 CM_SetField(history_msg, eExclusiveID, history_page, history_page_len);
231 CM_SetField(history_msg, eMsgSubject, history_page, history_page_len);
232 CM_SetField(history_msg, eSuppressIdx, HKEY("1")); /* suppress full text indexing */
233 snprintf(boundary, sizeof boundary, "Citadel--Multipart--%04x--%08lx", getpid(), time(NULL));
234 buf = (char*) malloc(1024);
235 len = snprintf(buf, 1024,
236 "Content-type: multipart/mixed; boundary=\"%s\"\n\n"
237 "This is a Citadel wiki history encoded as multipart MIME.\n"
238 "Each part is comprised of a diff script representing one change set.\n"
243 CM_SetAsField(history_msg, eMesageText, &buf, len);
246 /* Update the history message (regardless of whether it's new or existing) */
248 /* Remove the Message-ID from the old version of the history message. This will cause a brand
249 * new one to be generated, avoiding an uninitentional hit of the loop zapper when we replicate.
251 CM_FlushField(history_msg, emessageId);
253 /* Figure out the boundary string. We do this even when we generated the
254 * boundary string in the above code, just to be safe and consistent.
258 ptr = history_msg->cm_fields[eMesageText];
260 ptr = memreadline(ptr, buf, sizeof buf);
263 if (!IsEmptyStr(buf) && (!strncasecmp(buf, "Content-type:", 13))) {
265 (bmstrcasestr(buf, "multipart") != NULL)
266 && (bmstrcasestr(buf, "boundary=") != NULL)
268 safestrncpy(boundary, bmstrcasestr(buf, "\""), sizeof boundary);
270 qu = strchr(boundary, '\"');
272 strcpy(boundary, ++qu);
274 qu = strchr(boundary, '\"');
281 } while ( (IsEmptyStr(boundary)) && (*ptr != 0) );
284 * Now look for the first boundary. That is where we need to insert our fun.
286 if (!IsEmptyStr(boundary)) {
289 time_t Now = time(NULL);
291 snprintf(prefixed_boundary, sizeof(prefixed_boundary), "--%s", boundary);
293 CM_GetAsField(history_msg, eMesageText, &MsgText, &MsgTextLen);
295 ptr = bmstrcasestr(MsgText, prefixed_boundary);
301 char encoded_memo[1024];
303 NewMsgText = NewStrBufPlain(NULL, MsgTextLen + diffbuf_len + 1024);
306 memolen = snprintf(memo, sizeof(memo), "%s|%ld|%s|%s",
310 CtdlGetConfigStr("c_nodename"));
312 memolen = CtdlEncodeBase64(encoded_memo, memo, memolen, 0);
314 StrBufAppendBufPlain(NewMsgText, HKEY("--"), 0);
315 StrBufAppendBufPlain(NewMsgText, boundary, -1, 0);
316 StrBufAppendBufPlain(
319 "Content-type: text/plain\n"
320 "Content-Disposition: inline; filename=\""), 0);
322 StrBufAppendBufPlain(NewMsgText, encoded_memo, memolen, 0);
324 StrBufAppendBufPlain(
327 "Content-Transfer-Encoding: 8bit\n"
330 StrBufAppendBufPlain(NewMsgText, diffbuf, diffbuf_len, 0);
331 StrBufAppendBufPlain(NewMsgText, HKEY("\n"), 0);
333 StrBufAppendBufPlain(NewMsgText, ptr, MsgTextLen - (ptr - MsgText), 0);
335 CM_SetAsFieldSB(history_msg, eMesageText, &NewMsgText);
339 CM_SetAsField(history_msg, eMesageText, &MsgText, MsgTextLen);
342 CM_SetFieldLONG(history_msg, eTimestamp, Now);
344 CtdlSubmitMsg(history_msg, NULL, "");
347 syslog(LOG_ALERT, "Empty boundary string in history message. No history!\n");
351 CM_Free(history_msg);
357 * MIME Parser callback for wiki_history()
359 * The "filename" field will contain a memo field. All we have to do is decode
360 * the base64 and output it. The data is already in a delimited format suitable
361 * for our client protocol.
363 void wiki_history_callback(char *name, char *filename, char *partnum, char *disp,
364 void *content, char *cbtype, char *cbcharset, size_t length,
365 char *encoding, char *cbid, void *cbuserdata)
369 CtdlDecodeBase64(memo, filename, strlen(filename));
370 cprintf("%s\n", memo);
375 * Fetch a list of revisions for a particular wiki page
377 void wiki_history(char *pagename) {
379 char history_page_name[270];
381 struct CtdlMessage *msg;
383 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
385 if (r == om_not_logged_in) {
386 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
389 cprintf("%d An unknown error has occurred.\n", ERROR);
394 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
395 msgnum = CtdlLocateMessageByEuid(history_page_name, &CC->room);
397 msg = CtdlFetchMessage(msgnum, 1);
403 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
409 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
414 cprintf("%d Revision history for '%s'\n", LISTING_FOLLOWS, pagename);
415 mime_parser(CM_RANGE(msg, eMesageText), *wiki_history_callback, NULL, NULL, NULL, 0);
423 * MIME Parser callback for wiki_rev()
425 * The "filename" field will contain a memo field, which includes (among other things)
426 * the uuid of this revision. After we hit the desired revision, we stop processing.
428 * The "content" filed will contain "diff" output suitable for applying via "patch"
429 * to our temporary file.
431 void wiki_rev_callback(char *name, char *filename, char *partnum, char *disp,
432 void *content, char *cbtype, char *cbcharset, size_t length,
433 char *encoding, char *cbid, void *cbuserdata)
435 struct HistoryEraserCallBackData *hecbd = (struct HistoryEraserCallBackData *)cbuserdata;
442 /* Did a previous callback already indicate that we've reached our target uuid?
443 * If so, don't process anything else.
449 CtdlDecodeBase64(memo, filename, strlen(filename));
450 extract_token(this_rev, memo, 0, '|', sizeof this_rev);
453 /* Perform the patch */
454 fp = popen(PATCH " -f -s -p0 -r /dev/null >/dev/null 2>/dev/null", "w");
456 /* Replace the filenames in the patch with the tempfilename we're actually tweaking */
457 fprintf(fp, "--- %s\n", hecbd->tempfilename);
458 fprintf(fp, "+++ %s\n", hecbd->tempfilename);
460 ptr = (char *)content;
464 ptr = memreadline(ptr, buf, sizeof buf);
467 /* skip the first two lines; they contain bogus filenames */
470 fprintf(fp, "%s\n", buf);
473 } while ((*ptr != 0) && (ptr < ((char*)content + length)));
474 if (pclose(fp) != 0) {
475 syslog(LOG_ERR, "pclose() returned an error - patch failed\n");
479 if (!strcasecmp(this_rev, hecbd->stop_when)) {
480 /* Found our target rev. Tell any subsequent callbacks to suppress processing. */
481 syslog(LOG_DEBUG, "Target revision has been reached -- stop patching.\n");
488 * Fetch a specific revision of a wiki page. The "operation" string may be set to "fetch" in order
489 * to simply fetch the desired revision and store it in a temporary location for viewing, or "revert"
490 * to revert the currently active page to that revision.
492 void wiki_rev(char *pagename, char *rev, char *operation)
494 struct CitContext *CCC = CC;
496 char history_page_name[270];
499 struct CtdlMessage *msg;
501 struct HistoryEraserCallBackData hecbd;
505 r = CtdlDoIHavePermissionToReadMessagesInThisRoom();
507 if (r == om_not_logged_in) {
508 cprintf("%d Not logged in.\n", ERROR + NOT_LOGGED_IN);
511 cprintf("%d An unknown error has occurred.\n", ERROR);
516 if (!strcasecmp(operation, "revert")) {
517 r = CtdlDoIHavePermissionToPostInThisRoom(temp, sizeof temp, NULL, POST_LOGGED_IN, 0);
519 cprintf("%d %s\n", r, temp);
524 /* Begin by fetching the current version of the page. We're going to patch
525 * backwards through the diffs until we get the one we want.
527 msgnum = CtdlLocateMessageByEuid(pagename, &CCC->room);
529 msg = CtdlFetchMessage(msgnum, 1);
535 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
541 cprintf("%d Page '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
545 /* Output it to a temporary file */
547 CtdlMakeTempFileName(temp, sizeof temp);
548 fp = fopen(temp, "w");
550 r = fwrite(msg->cm_fields[eMesageText], msg->cm_lengths[eMesageText], 1, fp);
554 syslog(LOG_ERR, "%s: %m", temp);
558 /* Get the revision history */
560 snprintf(history_page_name, sizeof history_page_name, "%s_HISTORY_", pagename);
561 msgnum = CtdlLocateMessageByEuid(history_page_name, &CCC->room);
563 msg = CtdlFetchMessage(msgnum, 1);
569 if ((msg != NULL) && CM_IsEmpty(msg, eMesageText)) {
575 cprintf("%d Revision history for '%s' was not found.\n", ERROR+MESSAGE_NOT_FOUND, pagename);
579 /* Start patching backwards (newest to oldest) through the revision history until we
580 * hit the revision uuid requested by the user. (The callback will perform each one.)
583 memset(&hecbd, 0, sizeof(struct HistoryEraserCallBackData));
584 hecbd.tempfilename = temp;
585 hecbd.stop_when = rev;
586 striplt(hecbd.stop_when);
588 mime_parser(CM_RANGE(msg, eMesageText), *wiki_rev_callback, NULL, NULL, (void *)&hecbd, 0);
591 /* Were we successful? */
592 if (hecbd.done == 0) {
593 cprintf("%d Revision '%s' of page '%s' was not found.\n",
594 ERROR + MESSAGE_NOT_FOUND, rev, pagename
598 /* We have the desired revision on disk. Now do something with it. */
600 else if ( (!strcasecmp(operation, "fetch")) || (!strcasecmp(operation, "revert")) ) {
601 msg = malloc(sizeof(struct CtdlMessage));
602 memset(msg, 0, sizeof(struct CtdlMessage));
603 msg->cm_magic = CTDLMESSAGE_MAGIC;
604 msg->cm_anon_type = MES_NORMAL;
605 msg->cm_format_type = FMT_RFC822;
606 fp = fopen(temp, "r");
609 fseek(fp, 0L, SEEK_END);
611 fseek(fp, 0L, SEEK_SET);
612 msgbuf = malloc(len + 1);
613 rv = fread(msgbuf, len, 1, fp);
614 syslog(LOG_DEBUG, "did %d blocks of %ld bytes\n", rv, len);
616 CM_SetAsField(msg, eMesageText, &msgbuf, len);
622 else if (!strcasecmp(operation, "fetch")) {
623 CM_SetField(msg, eAuthor, HKEY("Citadel"));
624 CtdlCreateRoom(wwm, 5, "", 0, 1, 1, VIEW_BBS); /* Not an error if already exists */
625 msgnum = CtdlSubmitMsg(msg, NULL, wwm); /* Store the revision here */
628 * WARNING: VILE SLEAZY HACK
629 * This will avoid the 'message xxx is not in this room' security error,
630 * but only if the client fetches the message we just generated immediately
631 * without first trying to perform other fetch operations.
633 if (CCC->cached_msglist != NULL) {
634 free(CCC->cached_msglist);
635 CCC->cached_msglist = NULL;
636 CCC->cached_num_msgs = 0;
638 CCC->cached_msglist = malloc(sizeof(long));
639 if (CCC->cached_msglist != NULL) {
640 CCC->cached_num_msgs = 1;
641 CCC->cached_msglist[0] = msgnum;
645 else if (!strcasecmp(operation, "revert")) {
646 CM_SetFieldLONG(msg, eTimestamp, time(NULL));
647 if (!IsEmptyStr(CCC->user.fullname)) {
648 CM_SetField(msg, eAuthor, CCC->user.fullname, strlen(CCC->user.fullname));
651 if (!IsEmptyStr(CCC->cs_inet_email)) {
652 CM_SetField(msg, erFc822Addr, CCC->cs_inet_email, strlen(CCC->cs_inet_email));
655 if (!IsEmptyStr(CCC->room.QRname)) {
656 CM_SetField(msg, eOriginalRoom, CCC->room.QRname, strlen(CCC->room.QRname));
659 if (!IsEmptyStr(pagename)) {
660 CM_SetField(msg, eExclusiveID, pagename, strlen(pagename));
662 msgnum = CtdlSubmitMsg(msg, NULL, ""); /* Replace the current revision */
665 /* Theoretically it is impossible to get here, but throw an error anyway */
670 cprintf("%d %ld\n", CIT_OK, msgnum); /* Give the client a msgnum */
673 cprintf("%d Error %ld has occurred.\n", ERROR+INTERNAL_ERROR, msgnum);
677 /* We did all this work for nothing. Express anguish to the caller. */
679 cprintf("%d An unknown operation was requested.\n", ERROR+CMD_NOT_SUPPORTED);
689 * commands related to wiki management
691 void cmd_wiki(char *argbuf) {
697 extract_token(subcmd, argbuf, 0, '|', sizeof subcmd);
699 if (!strcasecmp(subcmd, "history")) {
700 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
701 wiki_history(pagename);
705 if (!strcasecmp(subcmd, "rev")) {
706 extract_token(pagename, argbuf, 1, '|', sizeof pagename);
707 extract_token(rev, argbuf, 2, '|', sizeof rev);
708 extract_token(operation, argbuf, 3, '|', sizeof operation);
709 wiki_rev(pagename, rev, operation);
713 cprintf("%d Invalid subcommand\n", ERROR + CMD_NOT_SUPPORTED);
719 * Module initialization
721 CTDL_MODULE_INIT(wiki)
725 CtdlRegisterMessageHook(wiki_upload_beforesave, EVT_BEFORESAVE);
726 CtdlRegisterProtoHook(cmd_wiki, "WIKI", "Commands related to Wiki management");
729 /* return our module name for the log */