Linux Security HOWTO: $B%U%!%$%k$H%U%!%$%k%7%9%F%`$N%;%-%e%j%F%#(B

5. $B%U%!%$%k$H%U%!%$%k%7%9%F%`$N%;%-%e%j%F%#(B

$B%7%9%F%`$r%M%C%H%o!<%/$K7R$0A0$K>/$7=`Hw$H7W2h$r9T$&$@$1$G(B, $B%7%9%F%`$H$=$NCf$N%G!<%?$r

$B%f!<%6$N%[!<%`%G%#%l%/%H%j$K(B SUID/SGID $B$7$?%W%m%0%i%`$rCV$$$F/etc/fstab $B$G(B nosuid $B%*%W%7%g%s$r;H$$$^$7$g$&(B. $B$^$?(B, $B%f!<%6$N%[!<%`%Q!<%F%#%7%g%s$d(B /var $B$G$O(B nodev $B$d(B noexec $B$r;H$*$&$H9M$($k$+$b$7$l$^$;$s(B. $B$3$l$i$N%*%W%7%g%s$O%W%m%0%i%`$N

NFS $B$rMQ$$$F%U%!%$%k%7%9%F%`$r%(%/%9%]!<%H$7$F$$$k>l9g$OI,$:(B, $B%"%/%;%9$r$G$-$k8B$j87$7$/@_Dj$7$F$/$@$5$$(B. $B$D$^$j(B /etc/exports $B$G$G$-$k8B$j87$7$$%"%/%;%9@)8B$r9T$C$F$/$@$5$$(B. $B$3$l$O%o%$%k%I%+!<%I$r;H$o$J$$$3$H(B, root $B$G$N=q$-9~$_%"%/%;%9$r5v2D$7$J$$$3$H(B, $B$G$-$k8B$jFI$_

$B%U%!%$%k:n@.$N(B umask $B$r$G$-$k8B$j87$7$/@_Dj$7$F$/$@$5$$(B. umask $B$N@_Dj(B $B$r$4Mw$/$@$5$$(B.

NFS $BEy$N%M%C%H%o!<%/%U%!%$%k%7%9%F%`$rMQ$$$F(B $B%U%!%$%k%7%9%F%`$r%^%&%s%H$7$F$$$k$J$i$P(B, $BI,$:(B /etc/exports $B$GE,@Z$J@)8B$rIU$1$?@_Dj$K$7$F$/$@$5$$(B. $BIaDL$O(B `nodev', `nosuid', $B$=$l$+$iB?J,(B `noexec' $B$,K>$^$7$$$G$7$g$&(B.

$B%G%U%)%k%H$N(B unlimited $B$rG'$a$k$N$G$O$J$/(B, $B%U%!%$%k%7%9%F%`$K@)8BCM$r@_Dj$7$^$7$g$&(B. $B%j%=!<%9@)8B$r9T$&(B PAM $B%b%8%e!<%k$H(B /etc/pam.d/limits.conf $B$r;H$C$F(B, $B%f!<%6JL$K@)8f$9$k$3$H$,$G$-$^$9(B. $BNc$($P(B, $B%0%k!<%W(B users $B$N@)8B$O0J2<$N$h$&$K$J$j$^$9(B:


                @users     hard  core    0
                @users     hard  nproc   50
                @users     hard  rss     5000

$B$3$N@_Dj$O(B, $B%3%"%U%!%$%k$N:n@.$r6X;_$7(B, $B%W%m%;%9$N?t$r(B 50 $B$K@)8B$7(B, $B%a%b%j$N;HMQNL$r%f!<%6(B 1 $B?M$"$?$j(B 5MB $B$K@)8B$9$k$b$N$G$9(B.

/var/log/wtmp, /var/run/utmp $B%U%!%$%k$K$O(B, $B%7%9%F%`$NA4$F$N%f!<%6$N%m%0%$%s5-O?$,5-O?$5$l$F$$$^$9(B. $B$3$N%U%!%$%k$O@dBP$$$8$i$l$J$$$h$&$K$7$J$/$F$O$J$j$^$;$s(B. $B$H$$$&$N$b(B, $B$3$N%U%!%$%k$r;H$C$F%f!<%6(B ($B$"$k$$$O?/F~o$N%7%9%F%`A`:n$K1F6A$rM?$($^$;$s(B.

immutable $B%S%C%H$r;H$&$H(B, $BC$7$?$j>e=q$-$9$k$3$H$rKI$0$3$H$,$G$-$^$9(B. $B$3$N%S%C%H$r;H$C$F(B, $BC/$+$,$3$N%U%!%$%k$KBP$9$k%7%s%\%j%C%/%j%s%/$r:n@.$9$k$N$rKI$0$3$H$b$G$-$^$9(B ($B$3$&$$$C$?%7%s%\%j%C%/%j%s%/$O:#$^$G(B /etc/passwd $B$d(B /etc/shadow $B$N:o=|$r4^$`967b$NpJs$K$D$$$F$O(B, $B%*%s%i%$%s%^%K%e%"%k$N(B chattr(1) $B$r;2>H$7$F$/$@$5$$(B.

SUID, SGID $B$5$l$?%U%!%$%k$,%7%9%F%`$K$"$k$H(B $B%;%-%e%j%F%#$K$H$C$F$O@x:_E*$K4m81$J$N$G(B, $B$3$l$i$N%U%!%$%k$O$-$A$s$H4F;k$7$F$$$J$1$l$P$J$j$^$;$s(B. $B$3$N$h$&$J%W%m%0%i%`$O$B%7%9%F%`>e$N(B SUID/SGID $B$5$l$?%W%m%0%i%`$rA4$F8+$D$1(B, $B$=$l$i$,$I$&$J$C$F$$$k$+$r4F;k$7$^$9(B. $B?/F~e$N(B SUID/SGID $B$5$l$?%W%m%0%i%`$rA4$F8+$D$1$k$K$O(B $B0J2<$N%3%^%s%I$r;H$$$^$9(B:


                root#  find / -type f \( -perm -04000 -o -perm -02000 \)

Debian $B%G%#%9%H%j%S%e!<%7%g%s$O(B, SUID $B$5$l$?%U%!%$%k$,B8:_$9$k$+$I$&$+$rD4$Y$k%8%g%V$rKhHU/var/log/setuid* $B$G;2>H$G$-$^$9(B.

$B2x$7$$%W%m%0%i%`$O(B chmod $B$r;H$C$F(B SUID $B$d(B SGID $B$N%Q!<%_%C%7%g%s$r

$BA4$F$N%f!<%6!<$,=q$-9~$_2DG=$J%U%!%$%k(B($BFC$K%7%9%F%`%U%!%$%k(B)$B$O(B, $B%/%i%C%+!<$,$"$J$?$N%7%9%F%`$K%"%/%;%9$7$F(B, $B=$@5$9$k$3$H$K$h$j(B $B%;%-%e%j%F%#%[!<%k$H$J$j$($^$9(B. $B$5$i$K(B, $BC/$b$,=q$-9~$a$k%G%#%l%/%H%j$H$$$&$b$N$b(B, $B%/%i%C%+!<$,<+M3$K%U%!%$%k$NDI2C!&:o=|$,$G$-$k$?$a4m81$G$9(B. $B%7%9%F%`>e$K$"$k$3$N$h$&$J%U%!%$%k$N0LCV$rFCDj$9$k$K$O(B, $B0J2<$N%3%^%s%I$r;H$$$^$9(B:


                root# find / -perm -2 ! -type l -ls

$B$=$l$+$i(B, $B$I$&$7$F$3$l$i$N%U%!%$%k$,=q$-9~$_2DG=$K$J$C$?$N$+$r3N$+$a$F$/$@$5$$(B. $BIaDL$KA`:n$7$F$$$k>l9g$G$b(B, /dev $B$N$$$/$D$+$N%U%!%$%k$d%7%s%\%j%C%/%j%s%/Ey$r4^$a$F(B, $BC/$G$b=q$-9~$a$k%U%!%$%k$,$$$/$D$+$"$j$^$9(B. $B$7$?$,$C$F(B, ! -type l $B$rMQ$$$F(B, $B@h$N(B find $B%3%^%s%I$N7k2L$+$i$3$l$i$r

$B=jM-


                root# find / -nouser -o -nogroup -print

.rhosts $B%U%!%$%k$r8+$D$1$k$3$H$b(B, $B%7%9%F%`4IM}o6HL3$N0lIt$G$9(B. $B$3$N%U%!%$%k$r%7%9%F%`$K@_CV$9$k$N$O5v2D$9$Y$-$G$J$$$+$i$G$9(B. $B%/%i%C%+!<$,%M%C%H%o!<%/A4BN$K%"%/%;%9$9$k2DG=@-$rF@$k$?$a$K$O(B, $B0BA4$G$J$$%"%+%&%s%H$,(B 1 $B$D$@$1$"$l$PNI$$$H$$$&$3$H$rK:$l$J$$$G$/$@$5$$(B. $B%7%9%F%`>e$NA4$F$N(B .rhosts $B%U%!%$%k$O0J2<$N%3%^%s%I$G8+$D$1$k$3$H$,$G$-$^$9(B:


               root# find /home -name .rhosts -print

$B:G8e$K$J$j$^$9$,(B, $B%7%9%F%`%U%!%$%k$N%Q!<%_%C%7%g%s$NJQ99$O(B, $B$7$h$&$H$7$F$$$k$3$H$rI,$:M}2r$7$F$+$i$K$7$F$/$@$5$$(B. $B2?$+$rF0$+$9$?$a$N3Z$JJ}K!$@$+$i$H$$$C$F(B, $B%U%!%$%k$N%Q!<%_%C%7%g%s$rJQ$($F$O$$$1$^$;$s(B. $B%Q!<%_%C%7%g%s$rJQ$($kA0$K$O(B, $B%U%!%$%k$N%Q!<%_%C%7%g%s$,$=$&$J$C$F$$$kM}M3$rI,$:M}2r$7$F$/$@$5$$(B.

5.1 umask $B$N@_Dj(B

umask $B%3%^%s%I$r;H$C$F(B, $B%7%9%F%`$N%G%U%)%k%H$N%U%!%$%k@8@.%b!<%I$r7h$a$k$3$H$,$G$-$^$9(B. umask $BCM$O@_Dj$7$?$$%U%!%$%k%b!<%I$N(B 8 $B?J?t$G$NJd?t$K$J$j$^$9(B. $B%Q!<%_%C%7%g%s$K4X$9$k;XDj$r2?$b9T$o$:$K%U%!%$%k$r@8@.$9$k$H(B, $B%Q!<%_%C%7%g%s$rM?$($k$Y$-$G$J$$2?o$O(B umask $BCM$N@_Dj$O(B 022, 027, 077 $B$G$9(B. 077 $B$O:G$b87$7$$@_Dj$G$9(B. $BDL>o$O(B umask $BCM$O(B /etc/profile $B$G@_Dj$5$l(B, $B%7%9%F%`$NA4%f!<%6$KE,MQ$5$l$^$9(B. $B%U%!%$%k@8@.%^%9%/$O(B, 777 $B$+$i4uK>$NCM$r0z$-;;$9$k$3$H$K$h$C$F7W;;$9$k$3$H$,$G$-$^$9(B. $B8@$$49$($k$H(B, umask $BCM$,(B 777 $B$G$"$l$P(B, $B?7$7$/@8@.$5$l$k%U%!%$%k$OC/$KBP$7$F$b(B $BFI$_=q$-$H


                # Set the user's default umask
                umask 033

$B$?$@$7(B, root $B%f!<%6$N(B umask $BCM$OI,$:(B 077 $B$K$7$F$/$@$5$$(B. $B$3$&$7$F$*$/$H(B, chmod $B$r;H$C$FL@<(E*$KJQ$($J$$8B$j(B, $BB>$N%f!<%6$NFI$_=q$-$Hl9g$K$O(B, $B?7$7$/@8@.$5$l$k%G%#%l%/%H%j$N%Q!<%_%C%7%g%s$O(B 744 $B$K$J$j$^$9(B. $B$3$NCM$O(B 777 $B$+$i(B 033 $B$r0z$$$FF@$i$l$?$b$N$G$9(B. umask $BCM(B 033 $B$rMQ$$$F?7$7$/@8@.$5$l$k%U%!%$%k$O%Q!<%_%C%7%g%s(B 644 $B$r;}$A$^$9(B.

Red Hat $B$r;H$C$F$*$j(B, Red Hat $B$N%f!<%6(B ID, $B%0%k!<%W(B ID $B$N:n@.J}K!(B (User Private Groups) $B$K=>$&>l9g(B, umask $B$K$O(B 002 $B$@$1@_Dj$7$F$$$l$P==J,$G$9(B. $B$=$NM}M3$O(B, $B%G%U%)%k%H$N@_Dj$G(B 1 $B%0%k!<%W$K(B 1 $B%f!<%6$7$+$$$J$$$?$a$G$9(B.

5.2 $B%U%!%$%k$N%Q!<%_%C%7%g%s(B

$B%7%9%F%`4IM}$r9T$&$Y$-$G$J$$%f!<%6$d%0%k!<%W$N8"8B$G$O(B $B%7%9%F%`%U%!%$%k$rJQ99$G$-$J$$$h$&$K$7$F$*$/$N$O=EMW$J$3$H$G$9(B.

UNIX $B$O(B $B%U%!%$%k$H%G%#%l%/%H%j$N%"%/%;%9@)8f$r(B 3 $B$D$NFC@-(B ($B=jM-o$K0l?M$@$1$r;X$9=jM-

$B0J2<$G(B UNIX $B$N%Q!<%_%C%7%g%s$r4JC1$K@bL@$7$^$9(B:

$B=jM-8"(B (ownership) - $B$"$k%N!<%I$d$=$N?F%N!<%I$N%Q!<%_%C%7%g%s@_Dj$r$I$N%f!<%6(B, $B%0%k!<%W$,9T$&$3$H$,$G$-$k$N$+$r<($7$^$9(B.

$B%Q!<%_%C%7%g%s(B(permissions) - $B%U%!%$%k$KBP$7$F9T$&$3$H$,$G$-$k(B $B%"%/%;%9$N

$BFI$_=P$7(B(read):

$B%U%!%$%k$NFbMF$r8+$k$3$H$,$G$-$k(B
$B%G%#%l%/%H%j$NFbMF$r8+$k$3$H$,$G$-$k(B

$B=q$-9~$_(B(write):

$B%U%!%$%k$NFbMF$NDI2C(B, $B=$@5$,$G$-$k(B
$B%G%#%l%/%H%j$N%U%!%$%k$N>C5n$d%U%!%$%k0\F0$,$G$-$k(B

$B%P%$%J%j$N%W%m%0%i%`$d%7%'%k%9%/%j%W%H$r

$BFI$_=P$7$N%Q!<%_%C%7%g%s$HAH$_9g$o$;$F(B, $B%G%#%l%/%H%jFb$rD4$Y$k$3$H$,$G$-$k(B

$B%F%-%9%HJ]B8B0@-(B: ($B%G%#%l%/%H%jMQ(B): $B%G%#%l%/%H%j$KE,MQ$9$k>l9g(B, $B!V(Bsticky $B%S%C%H!W$N0UL#$O%U%!%$%k$KE,MQ$9$k>l9g$H0[$J$j$^$9(B. sticky $B%S%C%H$,%G%#%l%/%H%j$K@_Dj$5$l$F$$$k>l9g$K:o=|$G$-$k%U%!%$%k$O(B, $B$=$N%G%#%l%/%H%j$X$N=q$-9~$_8"8B$,$"$C$?$H$7$F$b(B, $B<+J,$,=jM-$7$F$$$k%U%!%$%k$+(B $BL@<(E*$K=q$-9~$_5v2D$,M?$($i$l$F$$$k%U%!%$%k$@$1$G$9(B. $B$3$N%S%C%H$O(B /tmp $B$N$h$&$J%G%#%l%/%H%j$N$?$a$KMQ0U$5$l$?$b$N$G$9(B. $B$3$N$h$&$J%G%#%l%/%H%j$OC/$G$b=q$-9~$_$O$G$-$^$9$,(B, $BC/$G$b<+M3$K%U%!%$%k>C5n$rG'$a$k$N$OK>$^$7$/$"$j$^$;$s(B. $B%G%#%l%/%H%j$r>\:YI=<($9$k$H(B, sticky $B%S%C%H$O(B t $B$GI=$5$l$^$9(B.

SUID $BB0@-(B: ($B%U%!%$%kMQ(B): $B$3$l$O%U%!%$%k$X$N(B SUID $B%Q!<%_%C%7%g%s$r<($7$^$9(B. $B%f!<%6(B ID $B@_Dj%"%/%;%9%b!<%I$,=jM-

SGID $BB0@-(B: ($B%U%!%$%kMQ(B): $B%0%k!<%W$N%Q!<%_%C%7%g%s$G@_Dj$5$l$F$$$l$P(B, $B$3$N%S%C%H$O%U%!%$%k$N!V%0%k!<%W(B ID $B@_Dj!W>uBV$r@)8f$7$^$9(B. $B$3$l$O(B SUID $B$HF1$8$h$&$KF0:n$7$^$9$,(B, $B%f!<%6$G$O$J$/%0%k!<%W$,1F6A$r

SGID $BB0@-(B: ($B%G%#%l%/%H%jMQ(B): (chmod g+s directory $B$r9T$C$F(B) $B%G%#%l%/%H%j$K(B SGID $B%S%C%H$r@_Dj$7$?>l9g(B, $B$3$N%G%#%l%/%H%j$K:n$i$l$?%U%!%$%k$O(B $B%G%#%l%/%H%j$N%0%k!<%W$K@_Dj$5$l$?%0%k!<%W$r;}$A$^$9(B.

$B$"$J$?(B - $B%U%!%$%k$N=jM-

$B%0%k!<%W(B - $B$"$J$?$,=jB0$9$k%0%k!<%W(B

$BA40w(B - $B=jM-e$NA40w(B

$B%U%!%$%k$NNc(B:

        -rw-r--r--  1 kevin  users         114 Aug 28  1997 .zlogin
        1$BHVL\$N%S%C%H(B - $B%G%#%l%/%H%j$+(B?        (no)
         2$BHVL\$N%S%C%H(B - $B=jM-

$B0J2<$N9T$O(B, $B%"%/%;%98"$N@bL@$KI,MW$J:G>.8B$N%Q!<%_%C%7%g%s$r=8$a$?Nc$G$9(B. $Be$N%Q!<%_%C%7%g%s$rM?$($k$3$H$,I,MW$+$b$7$l$^$;$s$,(B, $B$3$l$i$N%U%!%$%k$K4X$9$k:G>.8B$N%Q!<%_%C%7%g%s$,0UL#$9$k$H$3$m$O(B $B



-r--------  $B=jM-e=q$-$d:o=|$r9T$&$3$H$,$G$-$^$9(B)
---x------  $B$3$N%W%m%0%i%`$Nl9g$O(B
            $B$3$l$@$1$G$OB-$j$:(B, $B$5$i$KFI$_9~$_%Q!<%_%C%7%g%s$,I,MW$G$9(B. 
---s------  $B!Vo$O%9%o%C%W%U%!%$%k$@$1(B
            $B$K;H$$$^$9(B. 
---t------  $BL50UL#$G$9(B($B0JA0(B sticky $B%S%C%H$@$C$?$b$N$G$9(B).

$B%G%#%l%/%H%j$NNc(B:


        drwxr-xr-x  3 kevin  users         512 Sep 19 13:47 .public_html/
        1$BHVL\$N%S%C%H(B - $B%G%#%l%/%H%j$+(B?        (yes, $B$?$/$5$s$N%U%!%$%k$,$"$k(B)
         2$BHVL\$N%S%C%H(B - $B=jM-

$B0J2<$N9T$O(B, $B%"%/%;%98"$N@bL@$KI,MW$J:G>.8B$N%Q!<%_%C%7%g%s$r=8$a$?Nc$G$9(B. $B<($7$?$b$N0J30$K$bB?$/$N%Q!<%_%C%7%g%s$,I,MW$@$H;W$&$+$b$7$l$^$;$s$,(B, $B$3$l$O$3$l$i$N%U%!%$%k$KBP$9$k:G>.8B$N%Q!<%_%C%7%g%s$G5-=R$G$-$k$O$:$G$9(B:



dr--------  $BFbMF$OI=<($G$-$^$9$,(B, $B%U%!%$%k$NB0@-$OFI$_=P$;$^$;$s(B
d--x------  $B%G%#%l%/%H%j$KF~$l(B, $B?M$O%U%!%$%k$r>C$9$3$H$r6X;_$7$^$9(B. 
            /tmp $B$G;H$o$l$^$9(B. 
d---s--s--  $BL50UL#$G$9(B.

$B%7%9%F%`@_Dj%U%!%$%k(B ($BIaDL$O(B /etc $B$K$"$j$^$9(B) $B$ODL>o(B, $B%b!<%I$,(B 640 (-rw-r-----) $B$G(B, root $B$,=jM-/etc/shadow $BEy(B) $B$O(B root $B$K$7$+FI$a$J$$>uBV$G$J$1$l$P$J$j$^$;$s$7(B, $B>/$J$/$H$b(B /etc $BFb$K$"$k%G%#%l%/%H%j$O(B $B$=$NB>$N%f!<%6$,%"%/%;%9$G$-$F$O$$$1$^$;$s(B.

SUID $B$5$l$?%7%'%k%9%/%j%W%H(B: SUID $B$5$l$?%7%'%k%9%/%j%W%H$O%;%-%e%j%F%#$K=EBg$J4m81$r5Z$\$9$N$G(B, $B%+!<%M%k$O$3$l$rL5;k$7$^$9(B. $B$=$N%7%'%k%9%/%j%W%H$,$I$l$@$10BA4$@$H;W$C$F$$$F$b(B, $B%/%i%C%+!<$K(B root $B$N%7%'%k$rC%$o$l$F$7$^$&2DG=@-$,$"$j$^$9(B.

5.3 $B%7%9%F%`@09g@-$N%A%'%C%/(B

$B%m!<%+%k$+$i$N(B ($B$=$7$F%M%C%H%o!<%/$+$i$N(B) $B%7%9%F%`$KBP$9$k967b$rH/8+$9$kJL$NNI$$J}K!$O(B, Tripwire, Aide, Osiris $B$N$h$&$J(B, $B%7%9%F%`$,$$$8$i$l$F$$$J$$$+$I$&$+$r%A%'%C%/$9$k(B $B%W%m%0%i%`$rHCM$H$7$F@5$7$$$3$H$,J,$+$C$F$$$k0JA0$NCM$N%G!<%?%Y!<%9$HHf3S$7$^$9(B. $B$7$?$,$C$F(B, $B$3$l$i$N%U%!%$%k$NJQ99$OA4$FCN$k$3$H$,$G$-$^$9(B.

$B$3$No$N%;%-%e%j%F%#4IM}:n6H$N0lIt$H$7$F

$BKhHU(B $B%U%m%C%T!<%G%#%9%/>e$N%A%'%C%/%W%m%0%i%`$rcrontab $B$r@_Dj$9$k$3$H$b$G$-$^$9(B. $B@_Dj$O0J2<$N$h$&$K$J$j$^$9(B.


                # set mailto
                MAILTO=kevin
                # run Tripwire
                15 05 * * * root /usr/local/adm/tcheck/tripwire

$B@09g@-%A%'%C%/%W%m%0%i%`$O(B, $B$$$6$H$J$C$F$+$i5$$E$/$h$jA0$K?/F~

Tripwire $B$N%*!<%W%s%=!<%9$J%P!<%8%g%s$O(B http://www.tripwiresecurity.com$B$K$"$j$^$9(B. $BL5NA$G$9(B. $B%^%K%e%"%k$H%5%]!<%H$OM-NA$GF~

Aide $B$O(B http://www.cs.tut.fi/~rammer/aide.html $B$K$"$j$^$9(B.

Osiris $B$O(B http://www.shmoo.com/osiris/ $B$+$i$I$&$>(B.

5.4 $B%H%m%$$NLZGO(B

$B!V%H%m%$$NLZGO(B (Trojan Horse)$B!W$O%[%a!<%m%9$N%$!<%j%"%9$K=q$+$l$F$$$k(B $BM-L>$J7WN,$KM3Mh$9$kL>A0$G$9(B. $B4pK\E*$J9M$(J}$O(B, $BJXMx$=$&$J%W%m%0%i%`$d%P%$%J%j$rMQ0U$7$F$*$-(B, $B$3$l$rB>?M$K%@%&%s%m!<%I$5$;$F(B root $B%f!<%6$H$7$F

$B$7$?$,$C$F(B, $B%^%7%s$K%W%m%0%i%`$r%$%s%9%H!<%k$9$k;~$K$OCm0U$,I,MW$G$9(B. Red Hat $B$O(B MD5 $B%A%'%C%/%5%`$H(B PGP $B=pL>$r;\$7$?(B RPM $B%U%!%$%k$rDs6!$7(B, $B%f!<%6$,K\J*$N%Q%C%1!<%8$rF~$N%G%#%9%H%j%S%e!<%7%g%s$K$bF1MM$N;EAH$_$,$"$j$^$9(B. $BAG@-$,CN$l$:(B, $B%=!<%9$bDs6!$5$l$F$$$J$$%P%$%J%j$r(B root $B8"8B$G

5.5 $B%Q%9%o!<%I$N%;%-%e%j%F%#$H0E9f2=(B

$B8=:_MQ$$$i$l$F$$$k%;%-%e%j%F%#5!G=$N$&$A:G$b=EMW$J$b$N$N$R$H$D$,(B $B%Q%9%o!<%I$G$9(B. $B$"$J$?$H$"$J$?$N%^%7%s$N%f!<%6$NN>J}$,(B, $B%Q%9%o!<%I$r0BA4$G?dB,$7$K$/$$$b$N$K$7$F$*$/$3$H$,Bg;v$G$9(B. $B:G6a$N(B Linux $B%G%#%9%H%j%S%e!<%7%g%s$N$[$H$s$I$K$O(B, $B4JC1$K?dB,$G$-$k%Q%9%o!<%I$O@_Dj$G$-$J$$$h$&$K$J$C$F$$$k(B passwd $B%W%m%0%i%`$,F~$C$F$$$^$9(B. passwd $B%W%m%0%i%`$,:G?7$N$b$N$G(B, $B$3$N$h$&$J5!G=$r;}$C$F$$$k$+$I$&$+3N$+$a$F$*$-$^$7$g$&(B.

$B0E9f2=$K$D$$$F$NFM$C9~$s$@5DO@$OK\=q$NHO0O$r1[$($F$7$^$$$^$9$,(B, $BF~LgDxEY$J$i$PNI$$$G$7$g$&(B. $B0E9f2=$OBgJQJXMx$G$9$7(B, $B$?$V$s:#F|$G$OI,?\$H$5$(8@$($k$G$7$g$&(B. $BHs>o$KB?$/$N$l$,FCD'$r;}$C$F$$$^$9(B.

$B$[$H$s$I$N(B UNIX(Linux $B$bNc30$G$O$"$j$^$;$s(B)$B$O(B, DES (Data Encryption Standard) $B$H8F$P$l$kJRJ}8~$N0E9f2=%"%k%4%j%:%`$r/etc/passwd $B$+(B ($B>/$70lHLE*$G$J$$$G$9$,(B) /etc/shadow $B$KJ]B8$5$l$^$9(B. $B%f!<%6$,%m%0%$%s$7$h$&$H$9$k$H(B, $BF~NO$7$?%Q%9%o!<%I$O:F$S0E9f2=$5$l(B, $B%Q%9%o!<%I$r3JG<$7$F$$$k%U%!%$%k$N3:Ev9`L\$HHf3S$5$l$^$9(B. $B$3$l$i$,0lCW$9$l$P%Q%9%o!<%I$OF1$8$O$:$J$N$G(B, $B%m%0%$%s$,5v2D$5$l$^$9(B. DES $B$OAPJ}8~$N0E9f2=%"%k%4%j%:%`(B ($B@5$7$$%-!<$rM?$($l$P(B, $B0E9f2=$bI|9f2=$b$G$-$k(B)$B$J$N$G$9$,(B, $B$[$H$s$I$N(B UNIX $B$,;H$C$F$$$k$N$O(B DES $B$N0l/etc/passwd ($B$^$?$O(B /etc/shadow) $B$NFbMF$+$i%Q%9%o!<%I$rF@$k$?$a$K0E9f$r2rFI$9$k$3$H$OIT2DG=$J$O$:$G$9(B.

$B%Q%9%o!<%I$,==J,$K%i%s%@%`$G$J$$>l9g(B, "Crack" $B$d(B "John the Ripper" ( crack $B>O$r;2>H(B)$B$N$h$&$JNOG$$;$N967b$G$b%Q%9%o!<%I$r?dB,$G$-$^$9(B. PAM $B%b%8%e!<%k(B ($B8e=R(B) $B$rMxMQ$9$l$P(B, $BJL$N0E9f2=%k!<%A%s(B (MD5 $B$J$I(B) $B$r;HMQ$G$-$^$9(B. Crack $B$K$bNI$$;H$$J}$,$"$j$^$9(B. $B%Q%9%o!<%I%G!<%?%Y!<%9$KBP$7$FDj4|E*$K(B Crack $B$r

$BNI$$%Q%9%o!<%I$N7h$aJ}$K4X$9$k>pJs$K$D$$$F$O(B http://consult.cern.ch/writeup/security/security_3.html $B$r;2>H$7$F$/$@$5$$(B.

5.6 PGP $B5Z$S8x3+800E9f(B

PGP $BEy$K;H$o$l$F$$$k8x3+800E9f$O(B, $B$"$k80$r0E9f2=$K;H$$(B, $BJL$N80$rI|9f2=$K;H$&0E9f$G$9(B. $B=>Mh$N0E9f$O(B, $B0E9f2=$HI|9f2=$KF1$880$r;H$C$F$$$^$7$?(B. $B$3$N80$ODL?.$NN>B&$,CN$C$F$$$J$1$l$P$J$i$:(B, $B2?$i$+$N0BA4$JJ}K!$GAj

$B0E9f$K;H$C$?80$r0BA4$KE>Aw$9$kI,MW@-$rL5$/$9$?$a(B, $B8x3+800E9f$G$O(B 2 $B$D$NJL!9$N80(B($B8x3+80$HHkL)80(B)$B$rMQ$$$^$9(B. $B3F<+$,;}$C$F$$$k8x3+80$OC/$G$b;H$&$3$H$,$G$-(B, $B0E9f2=$O$3$l$r;H$C$F9T$$$^$9(B. $B0lJ}(B, $B3F<+$O<+J,$NHkL)80$r;}$C$F$*$j(B, $B@5$7$$8x3+80$r;H$C$F0E9f2=$5$l$?%a%C%;!<%8$O$3$l$r;H$C$FI|9f2=$7$^$9(B.

$B8x3+80$r;H$&0E9f$K$bHkL)80$r;H$&0E9f$K$bMxE@$O$"$j$^$9(B. $B$3$l$i$N0c$$$K$D$$$F$O(B, $B$3$N%;%/%7%g%s$N:G8e$K<($9(B the RSA Cryptography FAQ $B$K@bL@$,$"$j$^$9(B.

PGP (Pretty Good Privacy) $B$O(B Linux $B$G$A$c$s$H%5%]!<%H$5$l$F$$$^$9(B. $B%P!<%8%g%s(B 2.62 $B$H(B 5.0 $B$NF0:n$,3NG'$5$l$F$$$^$9(B. PGP $B$X$NF~Lg$d;H$$J}$K$D$$$F$O(B, PGP FAQ $B$r8+$k$HNI$$$G$7$g$&(B. http://www.pgp.com/service/export/faq/55faq.cgi

$BI,$:(B, $B$"$J$?$N9q$GMxMQ$G$-$k%P!<%8%g%s$r;H$C$F$/$@$5$$(B. $B$3$l$O%"%a%j%+9g=09q@/I\$K$h$kM"=P@)8B$N$?$a$G$"$j(B, $B6/NO$J0E9f$rEE;RE*$K9q30$XE>Aw$9$k$3$H$,6X;_$5$l$F$$$k$+$i$G$9(B.

$B8=:_$OM"=P$N4IM}$O(B EAR(Export Administration Regulations)$B$,9T$C$F$$$^$9(B. $B$b$O$d(B ITAR ($BLuCm(B: International Traffic in Arms Regulations $B$NN,>N(B) $B$G$O4IM}$5$l$F$$$^$;$s(B.

Linux $B$G$N(B PGP $B$N@_Dj$K4X$9$k%9%F%C%W%P%$%9%F%C%W$N%,%$%I$b(B http://mercury.chem.pitt.edu/~angel/LinuxFocus/English/November1997/article7.html $B$K$"$j$^$9(B. $B$3$l$O(B PGP $B$N9q:]%P!<%8%g%sMQ$K=q$+$l$?$b$N$G$9$,(B, $B%"%a%j%+9g=09q%P!<%8%g%s$K$b4JC1$KE,MQ$G$-$^$9(B. $B:G?7%P!<%8%g%s$N(B Linux $B$N0lIt$G$O%Q%C%A$,I,MW$K$J$k$3$H$,$"$j$^$9(B. $B$3$N%Q%C%A$O(B ftp://metalab.unc.edu/pub/Linux/apps/crypto $B$GF~

PGP $B$r%*!<%W%s%=!<%9$G%U%j!<$K$=$&$H$7$F$$$k%W%m%8%'%/%H$,$"$j$^$9(B. GnuPG $B$O(B PGP $B$KCV$-49$($k$3$H$,$G$-$k(B, $B4{$K40@.$7$F$$$k%U%j!<$J%W%m%0%i%`$G$9(B. GnuPG $B$O(B IDEA $B$b(B RSA $B$b;H$C$F$$$J$$$N$G(B, $B@)8BL5$7$K;HMQ$9$k$3$H$,$G$-$^$9(B. GnuPG $B$O(B OpenPGP $B$K$[$\=`5r$7$F$$$^$9(B. $B>\$7$/$O(B GNU Privacy Guard $B$N(B WWW $B%Z!<%8(B ( http://www.gnupg.org/) $B$r$4Mw$/$@$5$$(B.

$BLuCm(B ($BN,8l$N0UL#(B):

IDEA: International Data Encryption Algorithm $B$NN,(B. 128 $B%S%C%H$NHkL)80$rMQ$$$?0E9f%"%k%4%j%:%`$G(B, $B%9%$%9$N(B Ascom-Tech $B
RSA: $B8x3+80$rMQ$$$?0E9f2=(B, $BEE;R=pL>$K;H$o$l$F$$$k%"%k%4%j%:%`$G(B, $BL>>N$O(B 3 $B?M$N3+H/

$B0E9f$K4X$9$k>\$7$$>pJs$O(B RSA cryptography FAQ $B$K=q$+$l$F$$$^$9(B. $B$3$l$O(B http://www.rsa.com/rsalabs/newfaq/ $B$+$iF~Z(B" $B$H$$$C$?MQ8l$K4X$9$k>pJs$,:\$C$F$$$^$9(B.

$BLuCm(B: $BF|K\8lLu$O(B http://www.rsa-japan.co.jp/faq/index.html $B$K$"$j$^$9(B.

5.7 SSL, S-HTTP, HTTPS, S/MIME

$B%f!<%6$O3FpJs$N$"$j$+$r>R2p$7$F$*$/$N$b0-$/$J$$$H;W$$$^$9(B.

SSL: - SSL ($B$"$k$$$O(B Secure Sockets Layer)$B$O(B Netscape $B$,3+H/$7$?0E9f2=e$G%;%-%e%j%F%#$rDs6!$7$^$9(B. SSL $B$O$$$/$D$+$N0[$J$k0E9f2=%W%m%H%3%k$H(B $B%/%i%$%"%s%H$H%5!<%P$NG'>Z$N$?$/$5$s$N(B Netscape Communicator $B$N%G!<%?0E9f2=$HF1MM$K(B, $B$3$l$O(B Communicator $B$r;H$C$?0BA4$JDL?.$N4pK\ItJ,$H$7$FMQ0U$5$l$F$$$^$9(B. $B>\$7$$>pJs$O(B http://www.consensus.com/security/ssl-talk-faq.html $B$K$"$j$^$9(B. Netscape $B$NB>$N%;%-%e%j%F%#5!9=$Nhttp://home.netscape.com/info/security-doc.html $B$GF~
S-HTTP: - S-HTTP $B$O%$%s%?!<%M%C%H>e$G$N(B $B0BA4$J%5!<%S%9$rDs6!$9$kJL$N%W%m%H%3%k$G$9(B. $B$3$N%W%m%H%3%k$O(B, $B5!L)@-(B (confidentiality), $BG'>Z(B (authentication), $B40A4@-(B (integrity), $BH]G'KI;_@-(B [ $BB>$NC/$+$H4V0c$&$3$H$,$"$jF@$J$$$3$H(B] $B$rM?$($k$?$a$K@_7W$5$l$F$*$j(B, $B$^$?(B, $B3F%H%i%s%6%/%7%g%s$K$*$1$kDL?.Aj$l$N%a%C%;!<%8$rFHN)$K0E9f2=$7$^$9(B. [ RSA Cryptography FAQ $B$N(B 138 $B%Z!<%8$h$j(B]
S/MIME: - S/MIME ($B$9$J$o$A(B Secure Multipurpose Internet Mail Extension)$B$O(B, $B0E9f2=EE;R%a!<%k$d$=$NB>$Ne$N%a%C%;!<%8$G;H$o$l$k(B $B0E9f2=$NI8=`$G$9(B. $B$3$l$O(B RSA $B$,3+H/$7$?%*!<%W%s$JI8=`$J$N$G(B, Linux $BMQ$N$b$N$b$?$V$s6a$$$&$A$KEP>l$9$k$G$7$g$&(B. S/MIME $B$K4X$9$k>\$7$$>pJs$O(B http://home.netscape.com/assist/security/smime/overview.html $B$K$"$j$^$9(B.

5.8 Linux $B$K$*$1$k(B IPSEC $B$N

CIPE $B$dB>$N7A<0$N%G!<%?0E9f2=$H$H$b$K(B, Linux $BMQ$N(B IPSEC $B$NZ(B, $B40A4@-(B, $B%"%/%;%9@)8f(B, $B5!L)@-$bDs6!$7$^$9(B. IPSEC $B$N>pJs$H%$%s%?!<%M%C%H%I%i%U%H$O(B http://www.ietf.org/html.charters/ipsec-charter.html $B$K$"$j$^$9(B. $B804IM}$r4^$a$FB>$N%W%m%H%3%k$X$N%j%s%/(B, IPSEC $B$N%a!<%j%s%0%j%9%H$d%"!<%+%$%V$b$"$j$^$9(B.

University of Arizona $B$G3+H/$5$l$?(B x-kernel Linux $B$H$$$&http://www.cs.arizona.edu/xkernel/hpcc-blue/linux.html $B$K$"$j$^$9(B. $BBg;(GD$K8@$&$H(B, x-kernel $B$O%+!<%M%k%l%Y%k$G$N%a%C%;!<%8%Q%C%7%s%0$N

$B$3$l$H$OJL$N%U%j!<$KMxMQ$G$-$k(B IPSEC $B$N $B!V$3$l$i$N%5!<%S%9$rMQ$$$k$H(B, $B?.Mj$G$-$J$$%M%C%H%o!<%/>e$K0BA4$J%H%s%M%k$r9=C[$9$k$3$H$,$G$-$^$9(B. $B?.Mj$G$-$J$$%M%C%H%o!<%/$rDL$k%G!<%?$OA4$F(B IPSEC $B%2!<%H%&%'%$%^%7%s$K$h$j0E9f2=$5$l(B, $B$=$NH?BP$NC<$N%2!<%H%&%'%$$K$h$C$FI|9f2=$5$l$^$9(B. $B$3$l$K$h$j2>A[%W%i%$%Y!<%H%M%C%H%o!<%/(B (Virtual Private Network, VPN) $B$,$G$-$^$9(B. $B$3$l$O(B, $B0BA4$G$J$$%$%s%?!<%M%C%H$G@\B3$5$l$?0[$J$kJ#?t$N%5%$%H$r4^$s$G$$$F$b(B, $B $B$H$N$3$H$G$9(B.

$B$3$l$O(B http://www.xs4all.nl/~freeswan/ $B$GF~$N7A<0$N0E9f$HF1MM$KM"=P$,@)8B$5$l$F$$$k$?$a(B, $B%G%U%)%k%H$G$O%+!<%M%k$H6&$KG[I[$5$l$F$$$^$;$s(B.

5.9 `ssh` (Secure Shell) $B$H(B `stelnet`

ssh $B$H(B stelnet $B$O(B, $B%j%b!<%H$N%7%9%F%`$K%m%0%$%s$7(B, $B0E9f2=$5$l$?@\B3$r9T$&$?$a$N%W%m%0%i%`72$G$9(B.

openssh $B$O(B rlogin, rsh, rcp $B$N0BA4$JBeMQIJ$H$7$F;H$o$l$k%W%m%0%i%`72$G$9(B. ssh $B$O(B 2 $B$D$N%[%9%H4V$NDL?.$H%f!<%6G'>Z$r(B $B8x3+800E9f$r;H$C$F0E9f2=$7$^$9(B. ssh $B$r;H$&$H0BA4$K%j%b!<%H%[%9%H$K%m%0%$%s$7$?$j(B, $B%[%9%H4V$G%G!<%?$r0BA4$K%3%T!<$7$?$j$9$k$3$H$,$G$-(B, $B3d$j9~$_967b(B($B%;%C%7%g%s$N%O%$%8%c%C%/(B)$B$d(B DNS $B:>>N$rKI$0$3$H$,$G$-$^$9(B. ssh $B$O@\B3>e$G%G!<%?05=L$b9T$$(B, $B%[%9%H4V$G$N0BA4$J(B X11 $B$NDL?.$b9T$$$^$9(B.

$B$$$^$G$O(B, ssh $B$K$O2?&MQ$Nssh home page http://www.datafellows.com $B$K$"$j$^$9(B.

The excellent Openssh $B$NAG@2$i$7$$$5$l$^$7$?(B. $B%U%j!<$G(B, BSD $B%i%$%;%s%9$N85$K$"$j$^$9(B. http://www.openssh.com $B$K$"$j$^$9(B.

"psst..." $B$H$$$&L>A0$N(B, ssh $B$r0l$+$i:F\$7$/$O(B http://www.net.lut.ac.uk/psst/ $B$r$4Mw$/$@$5$$(B.

ssh $B$r(B Windows PC $B$+$i(B Linux $B$N(B ssh $B%5!<%P$KBP$7$F;H$&$3$H$b$G$-$^$9(B. Windows $BMQ$N%/%i%$%"%s%H$Nhttp://guardian.htu.tuwien.ac.at/therapy/ssh/ $B$G$9$7(B, DataFellows $B$K$h$k>&MQ$Nhttp://www.datafellows.com $B$K$"$j$^$9(B.

SSLeay $B$O(B Netscape $B$N(B Secure Sockets Layer $B%W%m%H%3%k$N%U%j!<$N

$B$3$N%i%$%V%i%j$r;H$C$F(B, telnet $B@\B3>e$N%G!<%?$r0E9f2=$9$k(B telnet $B$N0BA4$JBeBX%W%m%0%i%`$,:n$i$l$^$7$?(B. SSH $B$H0[$J$j(B, stelnet $B$O(B Netscape $B$,3+H/$7$?(B SSL (Secure Sockets Layer) $B%W%m%H%3%k$r;H$$$^$9(B. Secure telnet $B$H(B Secure FTP $B$O(B SSLeay FAQ $B$+$i$?$I$C$F8+$D$1$k$3$H$,$G$-$^$9(B. $B$3$N(B FAQ $B$O(B http://www.psy.uq.oz.au/~ftp/Crypto/ $B$K$"$j$^$9(B.

$BLuCm(B: $BF|K\8lLu$,(B http://www.infoscience.co.jp/technical/crypto/ssleay_jp.html $B$K$"$j$^$9(B.

SRP $B$OJL$N0BA4$J(B telnet/ftp $B$N

$B!V(BSRP $B%W%m%8%'%/%H$O@$3&Cf$G%U%j!<$KMxMQ$G$-$k(B $B0BA4$J%$%s%?!<%M%C%H%=%U%H%&%'%"$r3+H/$7$F$$$^$9(B. $B40A4$K0BA4$J(B telnet $B$H(B ftp $B$NG[I[$r;O$a$H$7$F(B, $B2f!9$OZ$r(B, $B%;%-%e%j%F%#$N$?$a$K%f!<%6%$%s%?%U%'!<%9$r(B $B5>@7$K$7$J$$6/NO$J$b$N$KCV$-49$($?$$$H9M$($F$$$^$9(B. $B%;%-%e%j%F%#$,%*%W%7%g%s$J$s$F$H$s$G$b$J$$(B! $B%;%-%e%j%F%#$O%G%U%)%k%H$G$J$1$l$P$J$j$^$;$s!W(B

$B$H$N$3$H$G$9(B.

$B>\$7$$>pJs$K$D$$$F$O(B http://srp.stanford.edu/srp $B$r8+$F$/$@$5$$(B.

5.10 PAM - $B8r492DG=$JG'>Z%b%8%e!<%k(B

$B:G6a$N%P!<%8%g%s$N(B Red Hat Linux $B%G%#%9%H%j%S%e!<%7%g%s$G$O(B, "PAM" $B$H8F$P$l$kE}0l$5$l$?G'>ZJ}K!$,;H$o$l$F$$$^$9(B. PAM $B$r;H$&$H(B, $B%7%9%F%`$rF0:n$5$;$?$^$^$G(B $BG'>Z$NJ}K!$dMW7o$rJQ99$9$k$3$H$H%m!<%+%k$NG'>ZJ}K!$r%+%W%;%k2=$9$k$3$H$,(B $B2DG=$K$J$j$^$9(B. $B%P%$%J%j$O0l@Z:F%3%s%Q%$%k$9$kI,MW$,$"$j$^$;$s(B. PAM $B$N@_Dj$OK\=q$NHO0O$r1[$($^$9$,(B, $BI,$:(B PAM $B$N%&%'%V%5%$%H$r8+$F(B, $B>\$7$$>pJs$r8+$F$*$$$F$/$@$5$$(B. http://www.kernel.org/pub/linux/libs/pam/index.html

PAM $B$G2DG=$K$J$k$3$H$r$[$s$N>/$7$@$1Ns5s$7$^$9(B.

$B%Q%9%o!<%I$K(B DES $B0J30$N0E9f$rMQ$$$k(B. ($BNOG$$;$N2rFI$,Fq$7$/$J$j$^$9(B)
$B%5!<%S%9K832967b$r
$B%7%9%F%`$rF0:n$5$;$?$^$^(B, $B%7%c%I%&%Q%9%o!<%I(B($B8e=R(B)$B$rMxMQ2DG=$K$9$k(B.
$BFCDj$N%f!<%6$K$D$$$F(B, $BFCDj$N2s?t$N$_(B, $BFCDj$N>l=j$+$i%m%0%$%s$r5v2D$9$k(B.

$B%7%9%F%`$N%$%s%9%H!<%k$H@_Dj$r9T$&?t;~4V$N4V$K(B, $B.rhosts $B%U%!%$%k$N;HMQ$r%7%9%F%`A4BN$GL58z$K$9$k$3$H$,$G$-$^$9(B. $B@_Dj$O(B /etc/pam.d/rlogin $B$K0J2<$N$h$&$J9T$rDI2C$7$^$9(B:


                #
                # Disable rsh/rlogin/rexec for users
                #
                login auth required pam_rhosts_auth.so no_rhosts

5.11 $B0E9f$K$h$k(B IP $B$N%+%W%;%k2=(B (Cryptographic IP Encapsulation, CIPE)

$B$3$N%=%U%H%&%'%"$N4pK\E*$JL\E*$O(B, $B%$%s%?!<%M%C%H$N$h$&$J0BA4$G$J$$%Q%1%C%H%M%C%H%o!<%/$rDL$k0BA4$J(B ($B%H%i%U%#%C%/2r@O(B, $B56%a%C%;!<%8:.F~$r4^$`EpD0$KBP$7$F(B) $B%5%V%M%C%H%o!<%/4V@\B3$rDs6!$9$k$3$H$G$9(B.

CIPE $B$O%G!<%?$r%M%C%H%o!<%/%l%Y%k$G0E9f2=$7$^$9(B. $B$D$^$j(B, $B%M%C%H%o!<%/>e$N%[%9%H4V$rE>Aw$5$l$k%Q%1%C%H$,0E9f2=$5$l$^$9(B. $B0E9f2=%(%s%8%s$O%Q%1%C%H$rAw

CIPE $B$O(B, $B@\B3$4$H$K%=%1%C%H%l%Y%k$G%G!<%?$r0E9f2=$9$k(B SSH $B$H$O0[$J$j$^$9(B. $B0[$J$k%[%9%H>e$G

CIPE $B$O2>A[%W%i%$%Y!<%H%M%C%H%o!<%/(B (Virtual Private Network) $B$r9=C[$9$k$?$a$K(B, $B%H%s%M%j%s%0$G;H$&$3$H$,$G$-$^$9(B. $BDc%l%Y%k$N0E9f2=$K$O(B, $B%"%W%j%1!<%7%g%s%=%U%H%&%'%"$rJQ99$7$J$/$F$b(B, VPN $B$K@\B3$7$F$$$k(B 2 $B$D$N%M%C%H%o!<%/4V$GF)2aE*$KF0:n$5$;$k$3$H$,$G$-$k$H$$$&MxE@$,$"$j$^$9(B.

CIPE $B$N%I%-%e%a%s%H$+$i$NMWLs$G$9(B:

IPSEC $BI8=`$O(B, $B0E9f2=$5$l$?(B VPN $B$r9=C[$9$k$?$a(B ($BB>$K$b$"$j$^$9$,(B) $B$K;H$&$3$H$,$G$-$k%W%m%H%3%k72$rDj5A$7$F$$$^$9(B. $B$7$+$7(B, IPSEC $B$O%*%W%7%g%s$,$?$/$5$s$"$kHf3SE*=E$/$FJ#;($J%W%m%H%3%k72$G(B, $B%W%m%H%3%k72$N40A4$J

$B>\$7$$>pJs$O(B http://www.inka.de/~bigred/devel/cipe.html $B$K$"$j$^$9(B.

$BB>$N0E9f2=$HF1MM$NM"=P@)8B$N$?$a(B, CIPE $B$O%+!<%M%k$H0l=o$K$OG[I[$5$l$F$$$^$;$s(B.

5.12 Kerberos

Kerberos $B$O(B MIT $B$N(B Athena Project $B$G3+H/$5$l$?G'>Z%7%9%F%`$G$9(B. $B%f!<%6$,%m%0%$%s$7$?;~(B, Kerberos $B$O(B($B%Q%9%o!<%I$rMQ$$$F(B)$B%f!<%6$rG'>Z$7(B, $B%M%C%H%o!<%/>e$KJ,;6$7$F$$$kB>$N%5!<%P$d%[%9%H$KBP$7$F(B $B%f!<%6$N?HJ,$r>ZL@$9$k$?$a$NJ}K!$rDs6!$7$^$9(B.

$B$=$l$+$i(B, $B$3$NG'>Z>pJs$O(B rlogin $B$N$h$&$J%W%m%0%i%`$,;H$$(B, $B%f!<%6$,%Q%9%o!<%IL5$7$GB>$N%[%9%H$K%m%0%$%s$9$k$3$H$r5v2D$9$k$?$a$K;H$$$^$9(B (.rhosts $B%U%!%$%k$NBe$o$j(B). $B$3$NG'>ZJ}K!$r%a!<%k%7%9%F%`$G;H$($P(B, $B%a!<%k$,@5$7$$08@h$KG[C#$5$l$?$3$H$NJ]>Z$d(B, $BAw?.>h$C$F$$$kDL$j$N%f!<%6$G$"$k$3$H$NJ]>Z$,9T$($^$9(B.

Kerberos $B$*$h$S$3$l$KIUB0$7$F$$$k%W%m%0%i%`$O(B, $B$"$k%f!<%6$,(B, $B<+J,$rB>$N%f!<%6$G$"$k$H%7%9%F%`$K;W$o$;$k!V:>>N!W$r
Kerberos $B$K4X$9$k>\$7$$>pJs$O(B the kerberos FAQ $B$K$"$j(B, $B%3!<%I$O(B http://nii.isi.edu/info/kerberos/ $B$K$"$j$^$9(B.

[$B;29M(B: Stein, Jennifer G., Clifford Neuman, and Jeffrey L. Schiller. "Kerberos: An Authentication Service for Open Network Systems." USENIX Conference Proceedings, Dallas, Texas, Winter 1998.]

Kerberos $B$O%[%9%H$N%;%-%e%j%F%#8~>e$N$?$a$Ko$KJ#;($G$9$7(B, $BNc$($P(B SSH $B$[$I;H$o$l$F$$$k$o$1$G$b$"$j$^$;$s(B.

5.13 $B%7%c%I%&%Q%9%o!<%I(B

$B%7%c%I%&%Q%9%o!<%I$O(B, $B0E9f2=$5$l$?%Q%9%o!<%I>pJs$r0lHL%f!<%6$+$i1#$9J}$H$b(B, $B:G6a$N%P!<%8%g%s$G$O(B $B%G%U%)%k%H$G%7%c%I%&%Q%9%o!<%I$r;H$&$h$&$K$J$C$F$$$^$9$,(B, $B$[$+$N%7%9%F%`$G$O(B, $B0E9f2=$5$l$?%Q%9%o!<%I$OIaDL(B, $BC/$G$bFI$a$k(B /etc/passwd $B$K3JG<$5$l$F$$$^$9(B. $B$7$?$,$C$F(B, $BC/$G$b%Q%9%o!<%I?dB,%W%m%0%i%`$rpJs$OFC8"%f!<%6$7$+FI$a$J$$(B /etc/shadow $B%U%!%$%k$K3JG<$5$l$^$9(B. $B%7%c%I%&%Q%9%o!<%I$rMxMQ$9$k$?$a$K$O(B, $B%Q%9%o!<%I>pJs$X%"%/%;%9$9$kI,MW$,$"$k%f!<%F%#%j%F%#$r(B $BA4$F%7%c%I%&%Q%9%o!<%IBP1~$K:F%3%s%Q%$%k$9$kI,MW$,$"$j$^$9(B. ($B@h=R$N(B) PAM $B$r;H$C$F$$$l$P(B, $B%7%c%I%&%b%8%e!<%k$r;HMQ$9$k$@$1$G$h$/(B, $BH$7$F>\$7$$>pJs$rD4$Y$F$/$@$5$$(B. $B$3$N%I%-%e%a%s%H$O(B http://linuxdoc.org/HOWTO/Shadow-Password-HOWTO.html $B$K$"$j$^$9(B. $B$3$N%I%-%e%a%s%H$O8=:_$OB?>/8E$/$J$C$F$$$^$9$7(B, PAM $B$r%5%]!<%H$7$F$$$k%G%#%9%H%j%S%e!<%7%g%s$G$O$?$V$sITMW$G$7$g$&(B.

$BLuCm(B: $BOBLu$O(B http://www.linux.or.jp/JF/JFdocs/Shadow-Password-HOWTO.html $B$K$"$j$^$9(B.

5.14 "Crack" $B$*$h$S(B "John the Ripper"

$B?dB,$7$K$/$$%Q%9%o!<%I$r$D$1$k$3$H$r(B passwd $B%W%m%0%i%`$K$*$$$F6/@)$9$k$3$H$,$G$-$J$$>l9g$O(B, $B%Q%9%o!<%I$r%/%i%C%-%s%0$9$k%W%m%0%i%`$r
$B%Q%9%o!<%I%/%i%C%/$N%W%m%0%i%`$O(B, $BC1=c$J9M$($K4p$E$$$FF0:n$7$^$9(B. $B$D$^$j(B, $B<-=q$K:\$C$F$$$kC18l$H$3$l$i$NC18l$NJQ2=7A$r=g$K;n$9$N$G$9(B. $B$=$l$>$l$r0E9f2=$7(B, $B0E9f2=$5$l$?%Q%9%o!<%IJ8;zNs$HHf$Y$^$9(B. $B$3$l$i$,0lCW$9$l$P(B, $B%Q%9%o!<%I$,$o$+$j$^$9(B.

$B$3$N$h$&$J%W%m%0%i%`$O$?$/$5$s$"$j$^$9$,(B, $B$=$NCf$G$b(B "Crack" $B$H(B "John the Ripper" ( http://www.false.com/security/john/index.html) $B$N(B 2 $B$D$,M-L>$G$9(B. $B$3$l$i$O(B CPU $B%Q%o!<$rBgNL$K>CHq$7$^$9$,(B, $BM=$a$3$l$r/etc/passwd) $B$rF~$N%;%-%e%j%F%#%[!<%k$rFM$+$J$1$l$P$J$j$^$;$s$,(B, $B$=$l$OFI
$B:G$be$K(B Windows $B%^%7%s$,$"$k>l9g$K$O(B L0phtCrack $B$rD4$Y$k$Y$-$@$H$$$&$3$H$O8@5Z$7$F$*$/2ACM$,$"$k$G$7$g$&(B. $B$3$l$O(B Crack $B$N(B Windows $BMQ$Nhttp://www.l0pht.com $B$GF~
5.15 CFS ($B0E9f2=%U%!%$%k%7%9%F%`(B)$B$H(B TCFS ($BF)2aE*0E9f2=%U%!%$%k%7%9%F%`(B)

CFS $B$O%G%#%l%/%H%j%D%j!e$G(B NFS $B%5!<%P$rF0:n$5$;$^$9(B. RPM $B$O(B http://www.zedz.net/redhat/ $B$GF~pJs$O(B ftp://ftp.research.att.com/dist/mab/ $B$GF@$i$l$^$9(B.

TCFS $B$O(B CFS $B$r2~NI$7$?$b$N$G(B, $B%U%!%$%k%7%9%F%`$H$NE}9g$r$h$j?J$a$?$b$N$G$9(B. $B$7$?$,$C$F(B, $B%f!<%6$OF)2aE*$K0E9f2=%U%!%$%k%7%9%F%`$rMxMQ$9$k$3$H$,$G$-$^$9(B. $B>\$7$$>pJs$O(B http://edu-gw.dia.unisa.it/tcfs/ $B$GF@$i$l$^$9(B.

TCFS $B$OI,$:$7$b%U%!%$%k%7%9%F%`A4BN$G;H$&I,MW$O$"$j$^$;$s(B. $B$3$l$b%G%#%l%/%H%j%D%j!<$G;HMQ$9$k$3$H$,$G$-$^$9(B.

5.16 X11, SVGA, $B%G%#%9%W%l%$$K4X$9$k%;%-%e%j%F%#(B

X11

$B%0%i%U%#%C%/%G%#%9%W%l%$$r0BA4$K$7$F$*$-(B, $B967bpJs$rFI$s$@$j(B, $B%;%-%e%j%F%#%[!<%k$rFM$$$F(B root $B8"8B$rC%$C$?$j$G$-$J$$$h$&$K$7$F$*$/$3$H$O=EMW$G$9(B. X $B%"%W%j%1!<%7%g%s$r%M%C%H%o!<%/1[$7$K%j%b!<%H$GF0:n$5$;$k$3$H$b(B, $B%j%b!<%H$N%7%9%F%`$H$N$d$j$H$j$rA4ItEpD0$5$l$F$7$^$&4m81$rH<$&$3$H$,$"$j$^$9(B.

X $B$K$O%"%/%;%9@)8f5!9=$,$$$/$D$b$"$j$^$9(B. $B$=$NCf$G:G$b4JC1$J$b$N$O%[%9%H$K4p$E$/$b$N$G$9(B. xhost $B%3%^%s%I$rMQ$$$l$P(B, $B%G%#%9%W%l%$$X$N%"%/%;%9$,5v2D$5$l$k%[%9%H$r;XDj$G$-$^$9(B. $B$7$+$7(B, $B$3$N5!9=$OHs>o$K4m81$G$9(B. $B%^%7%s$K%"%/%;%9$G$-$k?M$O(B, xhost + $B$rl9g$K$O(B, $B$=$N%[%9%H$K%m%0%$%s$7$F$$$k%f!<%6$O(B $BC/$G$b%G%#%9%W%l%$$KIT@5%"%/%;%9$9$k$3$H$,$G$-$^$9(B.

$B%m%0%$%s$N$?$a$K(B xdm (X $B%G%#%9%W%l%$%^%M!<%8%c(B) $B$r;H$C$F$$$k>l9g(B, $B$:$C$HNI$$%"%/%;%9J}K!$G$"$k(B MIT-MAGIC-COOKIE-1 $B$r;H$$$^$7$g$&(B. $B$3$N5!9=$O(B 128$B%S%C%HD9$N!V%/%C%-!.Xauthority $B%U%!%$%k$K3JG<$7$^$9(B. $B%j%b!<%H$N%^%7%s$K%G%#%9%W%l%$$X$N%"%/%;%9$r5v2D$9$k$K$O(B, xauth $B%3%^%s%I$H(B .Xauthority $B%U%!%$%kFb$N>pJs$r;H$C$F(B, $B$=$N@\B3$@$1$r5v2D$9$k$h$&$K$7$^$9(B. Remote-X-Apps mini-howto $B$r$4Mw$/$@$5$$(B. $B$3$l$O(B http://linuxdoc.org/HOWTO/mini/Remote-X-Apps.html $B$GF~
$BLuCm(B: Remote-X-Apps $B$NOBLu(B $B$,$"$j$^$9(B.

X $B$N@\B3$r0BA4$K9T$&$?$a$K(B ssh ($BA0=R$N(B ssh $B$N9`$r;2>H$N$3$H(B) $B$r;H$&$3$H$b$G$-$^$9(B. ssh $B$K$O(B, $B%f!<%6$,F)2aE*$K07$&$3$H$,$G$-$k(B, $B$*$h$S%M%C%H%o!<%/>e$K0E9f2=$5$l$F$$$J$$%G!<%?$,N.$l$J$$(B, $B$H$$$&(B 2 $B$D$NMxE@$,$"$j$^$9(B.

X $B$N%;%-%e%j%F%#$K$D$$$F$N>\$7$$>pJs$K$D$$$F$O(B, $B%*%s%i%$%s%^%K%e%"%k$N(B Xsecurity $B$r;2>H$7$F$/$@$5$$(B. $B0BA4$J:v$H$7$F$O(B, $B%3%s%=!<%k$K%m%0%$%s$9$k$H$-$K$O(B xdm $B$r;H$$(B, $B%j%b!<%H$N%5%$%H$G(B X $B$N%W%m%0%i%`$rssh $B$r;H$&$3$H$G$9(B.

SVGA

SVGAlib $B$r;H$&%W%m%0%i%`$O%S%G%*4X78$N%O!<%I%&%'%"$rA`:n$9$k$?$a(B, $BIaDL$O(B root $B$K(B setuid $B$5$l$^$9(B. $B$3$l$OHs>o$K4m81$G$9(B. $B%W%m%0%i%`$,%/%i%C%7%e$7$?>l9g(B, $BIaDL$O%3%s%=!<%k$r85$KLa$9$?$a%^%7%s$r:F5/F0$7$J$/$F$O$J$i$J$/$J$C$F$7$^$$$^$9(B. $B$3$N$h$&$J%W%m%0%i%`$K$D$$$F$O(B, $B3N/$J$/$H$b>/$7$O?.MQ$G$-$k$3$H$r3N$+$a$F$/$@$5$$(B. $B$G$-$l$P(B, $B$=$b$=$b;H$o$J$$$N$,NI$$$G$7$g$&(B.

GGI (Generic Graphics Interface project)

Linux GGI $B%W%m%8%'%/%H$O(B Linux $B$N%S%G%*%$%s%?%U%'!<%9$NLdBj$K$D$$$F(B $B$R$H$D$N2r$rDs0F$7$h$&$H$9$k;n$_$G$9(B. GGI $B$G$O(B Linux $B$N%+!<%M%kFb$K>/$7%S%G%*4X78$N%3!<%I$rF~$l(B, $B$=$&$7$F%S%G%*$X%"%/%;%9$7$^$9(B. $B$D$^$j(B, GGI $B$r;H$($P$$$D$G$b%3%s%=!<%k$r@5>o$J>uBV$KLa$9$3$H$,$G$-$^$9(B. $B$^$?(B, secure attention key $B$r;H$&$3$H$,$G$-(B, $B%3%s%=!<%k$G%H%m%$$NLZGO$,F~$C$?(B login $B%W%m%0%i%`$r;H$o$l$k$N$rKI$2$^$9(B. http://synergy.caltech.edu/~ggi/

$B $BA0$N%Z!<%8(B $BL\