1#	$OpenBSD: integrity.sh,v 1.7 2013/02/20 08:27:50 djm Exp $
2#	Placed in the Public Domain.
3
4tid="integrity"
5
6# start at byte 2900 (i.e. after kex) and corrupt at different offsets
7# XXX the test hangs if we modify the low bytes of the packet length
8# XXX and ssh tries to read...
9tries=10
10startoffset=2900
11macs="hmac-sha1 hmac-md5 umac-64@openssh.com umac-128@openssh.com
12	hmac-sha1-96 hmac-md5-96 
13	hmac-sha1-etm@openssh.com hmac-md5-etm@openssh.com
14	umac-64-etm@openssh.com umac-128-etm@openssh.com
15	hmac-sha1-96-etm@openssh.com hmac-md5-96-etm@openssh.com"
16config_defined HAVE_EVP_SHA256 &&
17	macs="$macs hmac-sha2-256 hmac-sha2-512
18		hmac-sha2-256-etm@openssh.com hmac-sha2-512-etm@openssh.com"
19# The following are not MACs, but ciphers with integrated integrity. They are
20# handled specially below.
21config_defined OPENSSL_HAVE_EVPGCM && \
22	macs="$macs aes128-gcm@openssh.com aes256-gcm@openssh.com"
23
24# sshd-command for proxy (see test-exec.sh)
25cmd="$SUDO sh ${SRC}/sshd-log-wrapper.sh ${SSHD} ${TEST_SSH_LOGFILE} -i -f $OBJ/sshd_proxy"
26
27jot() {
28	awk "BEGIN { for (i = $2; i < $2 + $1; i++) { printf \"%d\n\", i } exit }"
29}
30
31for m in $macs; do
32	trace "test $tid: mac $m"
33	elen=0
34	epad=0
35	emac=0
36	ecnt=0
37	skip=0
38	for off in `jot $tries $startoffset`; do
39		skip=`expr $skip - 1`
40		if [ $skip -gt 0 ]; then
41			# avoid modifying the high bytes of the length
42			continue
43		fi
44		# modify output from sshd at offset $off
45		pxy="proxycommand=$cmd | $OBJ/modpipe -wm xor:$off:1"
46		case $m in
47			aes*gcm*)	macopt="-c $m";;
48			*)		macopt="-m $m";;
49		esac
50		output=`${SSH} $macopt -2F $OBJ/ssh_proxy -o "$pxy" \
51		    999.999.999.999 'printf "%4096s" " "' 2>&1`
52		if [ $? -eq 0 ]; then
53			fail "ssh -m $m succeeds with bit-flip at $off"
54		fi
55		ecnt=`expr $ecnt + 1`
56		output=`echo $output | tr -s '\r\n' '.'`
57		verbose "test $tid: $m @$off $output"
58		case "$output" in
59		Bad?packet*)	elen=`expr $elen + 1`; skip=3;;
60		Corrupted?MAC* | Decryption?integrity?check?failed*)
61				emac=`expr $emac + 1`; skip=0;;
62		padding*)	epad=`expr $epad + 1`; skip=0;;
63		*)		fail "unexpected error mac $m at $off";;
64		esac
65	done
66	verbose "test $tid: $ecnt errors: mac $emac padding $epad length $elen"
67	if [ $emac -eq 0 ]; then
68		fail "$m: no mac errors"
69	fi
70	expect=`expr $ecnt - $epad - $elen`
71	if [ $emac -ne $expect ]; then
72		fail "$m: expected $expect mac errors, got $emac"
73	fi
74done
75