Attempting to fix a segfault generated in Removecontext()

[citadel.git] / citadel / msgbase.c

diff --git a/citadel/msgbase.c b/citadel/msgbase.c
index ec76c0aed117594c1d11a4bded9d489007fc41b5..c252f5ff0d4b57f643c2dfd5046eae96dafda2a2 100644 (file)
--- a/citadel/msgbase.c
+++ b/citadel/msgbase.c
@@ -1,9 +1,9 @@
 /*
  * Implements the message store.
  *
- * Copyright (c) 1987-2010 by the citadel.org team
+ * Copyright (c) 1987-2011 by the citadel.org team
  *
- * This program is free software; you can redistribute it and/or modify
+ * This program is open source software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 3 of the License, or
  * (at your option) any later version.
@@ -15,7 +15,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
 #include "sysdep.h"
@@ -633,14 +633,16 @@ int CtdlForEachMessage(int mode, long ref, char *search_string,
 
        /* Load the message list */
        cdbfr = cdb_fetch(CDB_MSGLISTS, &CC->room.QRnumber, sizeof(long));
-       if (cdbfr != NULL) {
-               msglist = (long *) cdbfr->ptr;
-               num_msgs = cdbfr->len / sizeof(long);
-       } else {
+       if (cdbfr == NULL) {
                if (need_to_free_re) regfree(&re);
                return 0;       /* No messages at all?  No further action. */
        }
 
+       msglist = (long *) cdbfr->ptr;
+       num_msgs = cdbfr->len / sizeof(long);
+
+       cdbfr->ptr = NULL;      /* clear this so that cdb_free() doesn't free it */
+       cdb_free(cdbfr);        /* we own this memory now */
 
        /*
         * Now begin the traversal.
@@ -772,8 +774,22 @@ int CtdlForEachMessage(int mode, long ref, char *search_string,
                                ++num_processed;
                        }
                }
-       cdb_free(cdbfr);        /* Clean up */
        if (need_to_free_re) regfree(&re);
+
+       /*
+        * We cache the most recent msglist in order to do security checks later
+        */
+       if (CC->client_socket > 0) {
+               if (CC->cached_msglist != NULL) {
+                       free(CC->cached_msglist);
+               }
+               CC->cached_msglist = msglist;
+               CC->cached_num_msgs = num_msgs;
+       }
+       else {
+               free(msglist);
+       }
+
        return num_processed;
 }
 
@@ -1532,6 +1548,40 @@ void extract_encapsulated_message(char *name, char *filename, char *partnum, cha
 }
 
 
+/*
+ * Determine whether the specified message exists in the cached_msglist
+ * (This is a security check)
+ */
+int check_cached_msglist(long msgnum) {
+
+       /* cases in which we skip the check */
+       if (!CC) return om_ok;                                          /* not a session */
+       if (CC->client_socket <= 0) return om_ok;                       /* not a client session */
+       if (CC->cached_msglist == NULL) return om_access_denied;        /* no msglist fetched */
+       if (CC->cached_num_msgs == 0) return om_access_denied;          /* nothing to check */
+
+
+       /* Do a binary search within the cached_msglist for the requested msgnum */
+       int min = 0;
+       int max = (CC->cached_num_msgs - 1);
+
+       while (max >= min) {
+               int middle = min + (max-min) / 2 ;
+               if (msgnum == CC->cached_msglist[middle]) {
+                       return om_ok;
+               }
+               if (msgnum > CC->cached_msglist[middle]) {
+                       min = middle + 1;
+               }
+               else {
+                       max = middle - 1;
+               }
+       }
+
+       return om_access_denied;
+}
+
+
 /* 
  * Determine whether the currently logged in session has permission to read
  * messages in the current room.
@@ -1582,6 +1632,30 @@ int CtdlOutputMsg(long msg_num,          /* message number (local) to fetch */
                return(r);
        }
 
+       /*
+        * Check to make sure the message is actually IN this room
+        */
+       r = check_cached_msglist(msg_num);
+       if (r == om_access_denied) {
+               /* Not in the cache?  We get ONE shot to check it again. */
+               CtdlForEachMessage(MSGS_ALL, 0L, NULL, NULL, NULL, NULL, NULL);
+               r = check_cached_msglist(msg_num);
+       }
+       if (r != om_ok) {
+               syslog(LOG_DEBUG, "Security check fail: message %ld is not in %s\n",
+                       msg_num, CC->room.QRname
+               );
+               if (do_proto) {
+                       if (r == om_access_denied) {
+                               cprintf("%d message %ld was not found in this room\n",
+                                       ERROR + HIGHER_ACCESS_REQUIRED,
+                                       msg_num
+                               );
+                       }
+               }
+               return(r);
+       }
+
        /*
         * Fetch the message from disk.  If we're in HEADERS_FAST mode,
         * request that we don't even bother loading the body into memory.
@@ -2724,7 +2798,11 @@ long send_message(struct CtdlMessage *msg) {
 
        /* Get a new message number */
        newmsgid = get_new_message_number();
-       snprintf(msgidbuf, sizeof msgidbuf, "%010ld@%s", newmsgid, config.c_fqdn);
+       snprintf(msgidbuf, sizeof msgidbuf, "%08lX-%08lX@%s",
+               (long unsigned int) time(NULL),
+               (long unsigned int) newmsgid,
+               config.c_fqdn
+       );
 
        /* Generate an ID if we don't have one already */
        if (msg->cm_fields['I']==NULL) {