/usr/share/doc/imap-2000c/CONFIG gives instructions for increasing the security 
of pop/imap by hacking the code and recompiling.  following these instructions 
makes it impossible to participate in redhat upgrades.

imap as being historically one of the banes of linux/redhat security (remember 
the 5.x fiasco?) should, like named, take a command-line argument to allow 
chrooting the server immediately after authentication is complete.

below is the patch I use...mail goes to ~/mail/INBOX and the user is chrooted 
to ~/mail ...  it seems that ~/mail and INBOX should be two separate command-
line options to '/usr/sbin/imapd'

       stig

I tag this as 'high/security' because if the server's aren't chrooted, the 
server is much more vulnerable to bugs in the post-login segment of the 
server's code...and if you chroot the server, security updates for pre-chroot 
exploits cannot be located by up2date.





## /usr/src/redhat/SOURCES >> more imap-chroot.patch 
--- imap-2000c/src/osdep/unix/env_unix.c        Fri Dec  7 21:07:40 2001
+++ imap-2000c.hacked/src/osdep/unix/env_unix.c Fri Dec  7 21:17:44 2001
@@ -1,3 +1,5 @@
+#define CHROOT_SERVER 1
+
 /*
  * Program:    UNIX environment routines
  *
@@ -532,6 +534,13 @@
               char *argv[])
 {
   long ret = NIL;
+#ifdef CHROOT_SERVER
+  char chroot_subdir[MAILTMPLEN];
+  /* use "mail" subdirectory of home directory */
+  sprintf (chroot_subdir,"%s/mail",home);
+#endif
+                               /* paranoid site, lock out other directories */
+  
                                /* OK if matches authorization ID */
   if (authuser && strcmp (authuser,pw->pw_name)) {
     struct group *gr = getgrnam ((char *) admin_grp);
@@ -550,8 +559,8 @@
                                /* if same as EUID, treat as application */
   else if (pw->pw_uid == geteuid ()) ret = env_init (user,home);
 #ifdef CHROOT_SERVER
-                               /* paranoid site, lock out other directories */
-  else if (chdir (home) || chroot (home));
+  /* else if (chdir (home) || chroot (home)); */
+  else if (chdir (chroot_subdir) || chroot (chroot_subdir));
 #endif
   else {                       /* in case loginpw() smashes these */
                                /* in case user/home comes from pw struct */
@@ -645,6 +654,7 @@
 ^L
                                /* use real home directory */
   myHomeDir = cpystr (home ? home : ANONYMOUSHOME);
+
   dorc (strcat (strcpy (tmp,myHomeDir),"/.mminit"),T);
   dorc (strcat (strcpy (tmp,myHomeDir),"/.imaprc"),NIL);
 #ifndef DISABLE_AUTOMATIC_SHARED_NAMESPACES
@@ -761,7 +771,11 @@
 {
   char tmp[MAILTMPLEN];
   if (!sysInbox) {             /* initialize if first time */
+#if 0 /* qmail hack --stig */
     sprintf (tmp,"%s/%s",MAILSPOOL,myusername ());
+#else 
+    sprintf (tmp,"%s/INBOX",myhomedir ());
+#endif
     sysInbox = cpystr (tmp);   /* system inbox is from mail spool */
   }
   return sysInbox;



------------------
now this would seem to be close but imperfect.  it works for me for pop3, but 
doesn't work 100% for imap's needs...  (i was hoping i could get you started on 
this and you could finish it...)


it can read folders 

        0007 STATUS "big-attachments" (MESSAGES UNSEEN)
        * STATUS big-attachments (MESSAGES 6 UNSEEN 0)
        0007 OK STATUS completed

but not figure out which folders there are...

        00R4 LIST "" "*"
        * LIST (\NoInferiors) NIL INBOX
        00R4 OK LIST completed
        00R5 LSUB "" "*"
        * LSUB (\NoInferiors) NIL INBOX
        00R5 OK LSUB completed