joe@teltone.UUCP (05/25/83)
Since you have solved our news problem I thought I would try the problem we are having with mail. We are running a semi-private mail system with the following protection: d--x--x--x 2 root 1264 May 25 07:20 mail ./mail: total 342 -rw--w--w- 1 aaron 1172 May 22 17:28 aaron -rw--w--w- 1 alex 342 May 24 13:39 alex There are two intermitent problems associated with mail. One is that if two people simultaneously send mail to the same receipient the two message are intermingled in one mail message. For some reason the mail locking mechanism is not working. The other problem is that occasionally the file permissions are changed to -rw-r--r-- 1 alex 342 May 24 13:39 alex This occurs more frequently if the mail directory has permission d-wx-wx-wx 2 root 1264 May 25 07:20 mail I expect that there is a simpler way to have private mail and a more secure way also.
rjk@mgweed.UUCP (05/26/83)
The following secure mailing scheme works great for us:
Actual transcript of what happens as user "rjk":
-------------------------------------------------------
$ ls -ld /usr/mail
drwxrwx--x 2 bin mail 960 May 26 09:05 /usr/mail
$ ls -l /usr/mail/rjk
-rw-rw---- 1 rjk mail 417 May 26 09:05 /usr/mail/rjk
$ cat /usr/mail/rjk
>From jfs Thu May 26 09:04:22 1983
To: rjk
Subject: cu
...
$ ls -l /usr/mail/adm
-rw-rw---- 1 adm mail 825 Mar 22 15:30 /usr/mail/adm
$ cat /usr/mail/adm
cat: cannot open /usr/mail/adm
$ ls -l /usr/mail
/usr/mail unreadable
total 2
$ grep MFMODE /usr/src/cmd/mail.c
#define MFMODE 0660 /* create mode for `/usr/mail' files */
--------------------------------------------------------
No one can read anyone else's mail and the locking mechanism works as it
is supposed to.
Randy King
we13!mgweed!rjk