1 # $OpenBSD: keys-command.sh,v 1.7 2021/09/01 00:50:27 dtucker Exp $
2 # Placed in the Public Domain.
4 tid="authorized keys from command"
6 if [ -z "$SUDO" -a ! -w /var/run ]; then
7 echo "skipped (SUDO not set)"
8 echo "need SUDO to create file in /var/run, test won't work without"
12 rm -f $OBJ/keys-command-args
14 touch $OBJ/keys-command-args
15 chmod a+rw $OBJ/keys-command-args
17 expected_key_text=`awk '{ print $2 }' < $OBJ/ssh-ed25519.pub`
18 expected_key_fp=`$SSHKEYGEN -lf $OBJ/ssh-ed25519.pub | awk '{ print $2 }'`
20 # Establish a AuthorizedKeysCommand in /var/run where it will have
21 # acceptable directory permissions.
22 KEY_COMMAND="/var/run/keycommand_${LOGNAME}.$$"
23 trap "${SUDO} rm -f ${KEY_COMMAND}" 0
24 cat << _EOF | $SUDO sh -c "rm -f '$KEY_COMMAND' ; cat > '$KEY_COMMAND'"
26 echo args: "\$@" >> $OBJ/keys-command-args
27 echo "$PATH" | grep -q mekmitasdigoat && exit 7
28 test "x\$1" != "x${LOGNAME}" && exit 1
29 if test $# -eq 6 ; then
30 test "x\$2" != "xblah" && exit 2
31 test "x\$3" != "x${expected_key_text}" && exit 3
32 test "x\$4" != "xssh-rsa" && exit 4
33 test "x\$5" != "x${expected_key_fp}" && exit 5
34 test "x\$6" != "xblah" && exit 6
36 exec cat "$OBJ/authorized_keys_${LOGNAME}"
38 $SUDO chmod 0755 "$KEY_COMMAND"
40 if ! $OBJ/check-perm -m keys-command $KEY_COMMAND ; then
41 echo "skipping: $KEY_COMMAND is unsuitable as AuthorizedKeysCommand"
42 $SUDO rm -f $KEY_COMMAND
46 if [ -x $KEY_COMMAND ]; then
47 cp $OBJ/sshd_proxy $OBJ/sshd_proxy.bak
49 verbose "AuthorizedKeysCommand with arguments"
51 grep -vi AuthorizedKeysFile $OBJ/sshd_proxy.bak
52 echo AuthorizedKeysFile none
53 echo AuthorizedKeysCommand $KEY_COMMAND %u blah %k %t %f blah
54 echo AuthorizedKeysCommandUser ${LOGNAME}
57 # Ensure that $PATH is sanitised in sshd
58 env PATH=$PATH:/sbin/mekmitasdigoat \
59 ${SSH} -F $OBJ/ssh_proxy somehost true
64 verbose "AuthorizedKeysCommand without arguments"
65 # Check legacy behavior of no-args resulting in username being passed.
67 grep -vi AuthorizedKeysFile $OBJ/sshd_proxy.bak
68 echo AuthorizedKeysFile none
69 echo AuthorizedKeysCommand $KEY_COMMAND
70 echo AuthorizedKeysCommandUser ${LOGNAME}
73 # Ensure that $PATH is sanitised in sshd
74 env PATH=$PATH:/sbin/mekmitasdigoat \
75 ${SSH} -F $OBJ/ssh_proxy somehost true
80 skip "$KEY_COMMAND not executable (/var/run mounted noexec?)"