XSEND(1) UNIX Programmer's Manual XSEND(1)
xsend, xget, enroll - secret mail
S
\bSY
\bYN
\bNO
\bOP
\bPS
\bSI
\bIS
\bS
x
\bxs
\bse
\ben
\bnd
\bd person
D
\bDE
\bES
\bSC
\bCR
\bRI
\bIP
\bPT
\bTI
\bIO
\bON
\bN
These commands implement a secure communication channel; it
is like _
\bm_
\ba_
\bi_
\bl(1), but no one can read the messages except the
intended recipient. The method embodies a public-key cryp-
tosystem using knapsacks.
To receive messages, use _
\be_
\bn_
\br_
\bo_
\bl_
\bl; it asks you for a password
that you must subsequently quote in order to receive secret
To receive secret mail, use _
\bx_
\bg_
\be_
\bt. It asks for your pass-
word, then gives you the messages.
To send secret mail, use _
\bx_
\bs_
\be_
\bn_
\bd in the same manner as the
ordinary mail command. (However, it will accept only one
target). A message announcing the receipt of secret mail is
also sent by ordinary mail.
/usr/spool/secretmail/*.key: keys
/usr/spool/secretmail/*.[0-9]: messages
S
\bSE
\bEE
\bE A
\bAL
\bLS
\bSO
\bO
It should be integrated with ordinary mail. The announce-
ment of secret mail makes traffic analysis possible.
Printed 7/9/88 April 29, 1985 1