1# $OpenBSD: integrity.sh,v 1.24 2020/01/21 08:06:27 djm Exp $ 2# Placed in the Public Domain. 3 4tid="integrity" 5cp $OBJ/sshd_proxy $OBJ/sshd_proxy_bak 6 7# start at byte 2900 (i.e. after kex) and corrupt at different offsets 8tries=10 9startoffset=2900 10macs=`${SSH} -Q mac` 11# The following are not MACs, but ciphers with integrated integrity. They are 12# handled specially below. 13macs="$macs `${SSH} -Q cipher-auth`" 14 15# avoid DH group exchange as the extra traffic makes it harder to get the 16# offset into the stream right. 17#echo "KexAlgorithms -diffie-hellman-group*" \ 18# >> $OBJ/ssh_proxy 19 20# sshd-command for proxy (see test-exec.sh) 21cmd="$SUDO env SSH_SK_HELPER="$SSH_SK_HELPER" sh ${SRC}/sshd-log-wrapper.sh ${TEST_SSHD_LOGFILE} ${SSHD} -i -f $OBJ/sshd_proxy" 22 23for m in $macs; do 24 trace "test $tid: mac $m" 25 elen=0 26 epad=0 27 emac=0 28 etmo=0 29 ecnt=0 30 skip=0 31 for off in `jot $tries $startoffset`; do 32 skip=`expr $skip - 1` 33 if [ $skip -gt 0 ]; then 34 # avoid modifying the high bytes of the length 35 continue 36 fi 37 cp $OBJ/sshd_proxy_bak $OBJ/sshd_proxy 38 # modify output from sshd at offset $off 39 pxy="proxycommand=$cmd | $OBJ/modpipe -wm xor:$off:1" 40 if ${SSH} -Q cipher-auth | grep "^${m}\$" >/dev/null 2>&1 ; then 41 echo "Ciphers=$m" >> $OBJ/sshd_proxy 42 macopt="-c $m" 43 else 44 echo "Ciphers=aes128-ctr" >> $OBJ/sshd_proxy 45 echo "MACs=$m" >> $OBJ/sshd_proxy 46 macopt="-m $m -c aes128-ctr" 47 fi 48 verbose "test $tid: $m @$off" 49 ${SSH} $macopt -F $OBJ/ssh_proxy -o "$pxy" \ 50 -oServerAliveInterval=1 -oServerAliveCountMax=30 \ 51 999.999.999.999 'printf "%4096s" " "' >/dev/null 52 if [ $? -eq 0 ]; then 53 fail "ssh -m $m succeeds with bit-flip at $off" 54 fi 55 ecnt=`expr $ecnt + 1` 56 out=$(egrep -v "^debug" $TEST_SSH_LOGFILE | tail -2 | \ 57 tr -s '\r\n' '.') 58 case "$out" in 59 Bad?packet*) elen=`expr $elen + 1`; skip=3;; 60 Corrupted?MAC* | *message?authentication?code?incorrect*) 61 emac=`expr $emac + 1`; skip=0;; 62 padding*) epad=`expr $epad + 1`; skip=0;; 63 *Timeout,?server*) 64 etmo=`expr $etmo + 1`; skip=0;; 65 *) fail "unexpected error mac $m at $off: $out";; 66 esac 67 done 68 verbose "test $tid: $ecnt errors: mac $emac padding $epad length $elen timeout $etmo" 69 if [ $emac -eq 0 ]; then 70 fail "$m: no mac errors" 71 fi 72 expect=`expr $ecnt - $epad - $elen - $etmo` 73 if [ $emac -ne $expect ]; then 74 fail "$m: expected $expect mac errors, got $emac" 75 fi 76done 77