From 25505898530a333011f4fd5cbc841ad6b26c089c Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:40:04 +0200 Subject: Adding upstream version 1:9.2p1. Signed-off-by: Daniel Baumann --- regress/agent-restrict.sh | 495 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 495 insertions(+) create mode 100644 regress/agent-restrict.sh (limited to 'regress/agent-restrict.sh') diff --git a/regress/agent-restrict.sh b/regress/agent-restrict.sh new file mode 100644 index 0000000..a30aed7 --- /dev/null +++ b/regress/agent-restrict.sh @@ -0,0 +1,495 @@ +# $OpenBSD: agent-restrict.sh,v 1.5 2022/01/13 04:53:16 dtucker Exp $ +# Placed in the Public Domain. + +tid="agent restrictions" + +SSH_AUTH_SOCK="$OBJ/agent.sock" +export SSH_AUTH_SOCK +rm -f $SSH_AUTH_SOCK $OBJ/agent.log $OBJ/host_[abcdex]* $OBJ/user_[abcdex]* +rm -f $OBJ/sshd_proxy_host* $OBJ/ssh_output* $OBJ/expect_* +rm -f $OBJ/ssh_proxy[._]* $OBJ/command + +verbose "generate keys" +for h in a b c d e x ca ; do + $SSHKEYGEN -q -t ed25519 -C host_$h -N '' -f $OBJ/host_$h || \ + fatal "ssh-keygen hostkey failed" + $SSHKEYGEN -q -t ed25519 -C user_$h -N '' -f $OBJ/user_$h || \ + fatal "ssh-keygen userkey failed" +done + +# Make some hostcerts +for h in d e ; do + id="host_$h" + $SSHKEYGEN -q -s $OBJ/host_ca -I $id -n $id -h $OBJ/host_${h}.pub || \ + fatal "ssh-keygen certify failed" +done + +verbose "prepare client config" +egrep -vi '(identityfile|hostname|hostkeyalias|proxycommand)' \ + $OBJ/ssh_proxy > $OBJ/ssh_proxy.bak +cat << _EOF > $OBJ/ssh_proxy +IdentitiesOnly yes +ForwardAgent yes +ExitOnForwardFailure yes +_EOF +cp $OBJ/ssh_proxy $OBJ/ssh_proxy_noid +for h in a b c d e ; do + cat << _EOF >> $OBJ/ssh_proxy +Host host_$h + Hostname host_$h + HostkeyAlias host_$h + IdentityFile $OBJ/user_$h + ProxyCommand ${SUDO} env SSH_SK_HELPER=\"$SSH_SK_HELPER\" sh ${SRC}/sshd-log-wrapper.sh ${TEST_SSHD_LOGFILE} ${SSHD} -i -f $OBJ/sshd_proxy_host_$h +_EOF + # Variant with no specified keys. + cat << _EOF >> $OBJ/ssh_proxy_noid +Host host_$h + Hostname host_$h + HostkeyAlias host_$h + ProxyCommand ${SUDO} env SSH_SK_HELPER=\"$SSH_SK_HELPER\" sh ${SRC}/sshd-log-wrapper.sh ${TEST_SSHD_LOGFILE} ${SSHD} -i -f $OBJ/sshd_proxy_host_$h +_EOF +done +cat $OBJ/ssh_proxy.bak >> $OBJ/ssh_proxy +cat $OBJ/ssh_proxy.bak >> $OBJ/ssh_proxy_noid + +LC_ALL=C +export LC_ALL +echo "SetEnv LC_ALL=${LC_ALL}" >> sshd_proxy + +verbose "prepare known_hosts" +rm -f $OBJ/known_hosts +for h in a b c x ; do + (printf "host_$h " ; cat $OBJ/host_${h}.pub) >> $OBJ/known_hosts +done +(printf "@cert-authority host_* " ; cat $OBJ/host_ca.pub) >> $OBJ/known_hosts + +verbose "prepare server configs" +egrep -vi '(hostkey|pidfile)' $OBJ/sshd_proxy \ + > $OBJ/sshd_proxy.bak +for h in a b c d e; do + cp $OBJ/sshd_proxy.bak $OBJ/sshd_proxy_host_$h + cat << _EOF >> $OBJ/sshd_proxy_host_$h +ExposeAuthInfo yes +PidFile none +Hostkey $OBJ/host_$h +_EOF +done +for h in d e ; do + echo "HostCertificate $OBJ/host_${h}-cert.pub" \ + >> $OBJ/sshd_proxy_host_$h +done +# Create authorized_keys with canned command. +reset_keys() { + _whichcmd="$1" + _command="" + case "$_whichcmd" in + authinfo) _command="cat \$SSH_USER_AUTH" ;; + keylist) _command="$SSHADD -L | cut -d' ' -f-2 | sort" ;; + *) fatal "unsupported command $_whichcmd" ;; + esac + trace "reset keys" + >$OBJ/authorized_keys_$USER + for h in e d c b a; do + (printf "%s" "restrict,agent-forwarding,command=\"$_command\" "; + cat $OBJ/user_$h.pub) >> $OBJ/authorized_keys_$USER + done +} +# Prepare a key for comparison with ExposeAuthInfo/$SSH_USER_AUTH. +expect_key() { + _key="$OBJ/${1}.pub" + _file="$OBJ/$2" + (printf "publickey " ; cut -d' ' -f-2 $_key) > $_file +} +# Prepare expect_* files to compare against authinfo forced command to ensure +# keys used for authentication match. +reset_expect_keys() { + for u in a b c d e; do + expect_key user_$u expect_$u + done +} +# ssh to host, expecting success and that output matched expectation for +# that host (expect_$h file). +expect_succeed() { + _id="$1" + _case="$2" + shift; shift; _extra="$@" + _host="host_$_id" + trace "connect $_host expect success" + rm -f $OBJ/ssh_output + ${SSH} $_extra -F $OBJ/ssh_proxy $_host true > $OBJ/ssh_output + _s=$? + test $_s -eq 0 || fail "host $_host $_case fail, exit status $_s" + diff $OBJ/ssh_output $OBJ/expect_${_id} || + fail "unexpected ssh output" +} +# ssh to host using explicit key, expecting success and that the key was +# actually used for authentication. +expect_succeed_key() { + _id="$1" + _key="$2" + _case="$3" + shift; shift; shift; _extra="$@" + _host="host_$_id" + trace "connect $_host expect success, with key $_key" + _keyfile="$OBJ/$_key" + rm -f $OBJ/ssh_output + ${SSH} $_extra -F $OBJ/ssh_proxy_noid \ + -oIdentityFile=$_keyfile $_host true > $OBJ/ssh_output + _s=$? + test $_s -eq 0 || fail "host $_host $_key $_case fail, exit status $_s" + expect_key $_key expect_key + diff $OBJ/ssh_output $OBJ/expect_key || + fail "incorrect key used for authentication" +} +# ssh to a host, expecting it to fail. +expect_fail() { + _host="$1" + _case="$2" + shift; shift; _extra="$@" + trace "connect $_host expect failure" + ${SSH} $_extra -F $OBJ/ssh_proxy $_host true >/dev/null && \ + fail "host $_host $_case succeeded unexpectedly" +} +# ssh to a host using an explicit key, expecting it to fail. +expect_fail_key() { + _id="$1" + _key="$2" + _case="$3" + shift; shift; shift; _extra="$@" + _host="host_$_id" + trace "connect $_host expect failure, with key $_key" + _keyfile="$OBJ/$_key" + ${SSH} $_extra -F $OBJ/ssh_proxy_noid -oIdentityFile=$_keyfile \ + $_host true > $OBJ/ssh_output && \ + fail "host $_host $_key $_case succeeded unexpectedly" +} +# Move the private key files out of the way to force use of agent-hosted keys. +hide_privatekeys() { + trace "hide private keys" + for u in a b c d e x; do + mv $OBJ/user_$u $OBJ/user_x$u || fatal "hide privkey $u" + done +} +# Put the private key files back. +restore_privatekeys() { + trace "restore private keys" + for u in a b c d e x; do + mv $OBJ/user_x$u $OBJ/user_$u || fatal "restore privkey $u" + done +} +clear_agent() { + ${SSHADD} -D > /dev/null 2>&1 || fatal "clear agent failed" +} + +reset_keys authinfo +reset_expect_keys + +verbose "authentication w/o agent" +for h in a b c d e ; do + expect_succeed $h "w/o agent" + wrongkey=user_e + test "$h" = "e" && wrongkey=user_a + expect_succeed_key $h $wrongkey "\"wrong\" key w/o agent" +done +hide_privatekeys +for h in a b c d e ; do + expect_fail $h "w/o agent" +done +restore_privatekeys + +verbose "start agent" +${SSHAGENT} ${EXTRA_AGENT_ARGS} -d -a $SSH_AUTH_SOCK > $OBJ/agent.log 2>&1 & +AGENT_PID=$! +trap "kill $AGENT_PID" EXIT +sleep 4 # Give it a chance to start +# Check that it's running. +${SSHADD} -l > /dev/null 2>&1 +if [ $? -ne 1 ]; then + fail "ssh-add -l did not fail with exit code 1" +fi + +verbose "authentication with agent (no restrict)" +for u in a b c d e x; do + $SSHADD -q $OBJ/user_$u || fatal "add key $u unrestricted" +done +hide_privatekeys +for h in a b c d e ; do + expect_succeed $h "with agent" + wrongkey=user_e + test "$h" = "e" && wrongkey=user_a + expect_succeed_key $h $wrongkey "\"wrong\" key with agent" +done + +verbose "unrestricted keylist" +reset_keys keylist +rm -f $OBJ/expect_list.pre +# List of keys from agent should contain everything. +for u in a b c d e x; do + cut -d " " -f-2 $OBJ/user_${u}.pub >> $OBJ/expect_list.pre +done +sort $OBJ/expect_list.pre > $OBJ/expect_list +for h in a b c d e; do + cp $OBJ/expect_list $OBJ/expect_$h + expect_succeed $h "unrestricted keylist" +done +restore_privatekeys + +verbose "authentication with agent (basic restrict)" +reset_keys authinfo +reset_expect_keys +for h in a b c d e; do + $SSHADD -h host_$h -H $OBJ/known_hosts -q $OBJ/user_$h \ + || fatal "add key $u basic restrict" +done +# One more, unrestricted +$SSHADD -q $OBJ/user_x || fatal "add unrestricted key" +hide_privatekeys +# Authentication to host with expected key should work. +for h in a b c d e ; do + expect_succeed $h "with agent" +done +# Authentication to host with incorrect key should fail. +verbose "authentication with agent incorrect key (basic restrict)" +for h in a b c d e ; do + wrongkey=user_e + test "$h" = "e" && wrongkey=user_a + expect_fail_key $h $wrongkey "wrong key with agent (basic restrict)" +done + +verbose "keylist (basic restrict)" +reset_keys keylist +# List from forwarded agent should contain only user_x - the unrestricted key. +cut -d " " -f-2 $OBJ/user_x.pub > $OBJ/expect_list +for h in a b c d e; do + cp $OBJ/expect_list $OBJ/expect_$h + expect_succeed $h "keylist (basic restrict)" +done +restore_privatekeys + +verbose "username" +reset_keys authinfo +reset_expect_keys +for h in a b c d e; do + $SSHADD -h "${USER}@host_$h" -H $OBJ/known_hosts -q $OBJ/user_$h \ + || fatal "add key $u basic restrict" +done +hide_privatekeys +for h in a b c d e ; do + expect_succeed $h "wildcard user" +done +restore_privatekeys + +verbose "username wildcard" +reset_keys authinfo +reset_expect_keys +for h in a b c d e; do + $SSHADD -h "*@host_$h" -H $OBJ/known_hosts -q $OBJ/user_$h \ + || fatal "add key $u basic restrict" +done +hide_privatekeys +for h in a b c d e ; do + expect_succeed $h "wildcard user" +done +restore_privatekeys + +verbose "username incorrect" +reset_keys authinfo +reset_expect_keys +for h in a b c d e; do + $SSHADD -h "--BADUSER@host_$h" -H $OBJ/known_hosts -q $OBJ/user_$h \ + || fatal "add key $u basic restrict" +done +hide_privatekeys +for h in a b c d e ; do + expect_fail $h "incorrect user" +done +restore_privatekeys + + +verbose "agent restriction honours certificate principal" +reset_keys authinfo +reset_expect_keys +clear_agent +$SSHADD -h host_e -H $OBJ/known_hosts -q $OBJ/user_d || fatal "add key" +hide_privatekeys +expect_fail d "restricted agent w/ incorrect cert principal" +restore_privatekeys + +# Prepares the script used to drive chained ssh connections for the +# multihop tests. Believe me, this is easier than getting the escaping +# right for 5 hops on the command-line... +prepare_multihop_script() { + MULTIHOP_RUN=$OBJ/command + cat << _EOF > $MULTIHOP_RUN +#!/bin/sh +#set -x +me="\$1" ; shift +next="\$1" +if test ! -z "\$me" ; then + rm -f $OBJ/done + echo "HOSTNAME host_\$me" + echo "AUTHINFO" + cat \$SSH_USER_AUTH +fi +echo AGENT +$SSHADD -L | egrep "^ssh" | cut -d" " -f-2 | sort +if test -z "\$next" ; then + touch $OBJ/done + echo "FINISH" + e=0 +else + echo NEXT + ${SSH} -F $OBJ/ssh_proxy_noid -oIdentityFile=$OBJ/user_a \ + host_\$next $MULTIHOP_RUN "\$@" + e=\$? +fi +echo "COMPLETE \"\$me\"" +if test ! -z "\$me" ; then + if test ! -f $OBJ/done ; then + echo "DONE MARKER MISSING" + test \$e -eq 0 && e=63 + fi +fi +exit \$e +_EOF + chmod u+x $MULTIHOP_RUN +} + +# Prepare expected output for multihop tests at expect_a +prepare_multihop_expected() { + _keys="$1" + _hops="a b c d e" + test -z "$2" || _hops="$2" + _revhops=$(echo "$_hops" | rev) + _lasthop=$(echo "$_hops" | sed 's/.* //') + + rm -f $OBJ/expect_keys + for h in a b c d e; do + cut -d" " -f-2 $OBJ/user_${h}.pub >> $OBJ/expect_keys + done + rm -f $OBJ/expect_a + echo "AGENT" >> $OBJ/expect_a + test "x$_keys" = "xnone" || sort $OBJ/expect_keys >> $OBJ/expect_a + echo "NEXT" >> $OBJ/expect_a + for h in $_hops ; do + echo "HOSTNAME host_$h" >> $OBJ/expect_a + echo "AUTHINFO" >> $OBJ/expect_a + (printf "publickey " ; cut -d" " -f-2 $OBJ/user_a.pub) >> $OBJ/expect_a + echo "AGENT" >> $OBJ/expect_a + if test "x$_keys" = "xall" ; then + sort $OBJ/expect_keys >> $OBJ/expect_a + fi + if test "x$h" != "x$_lasthop" ; then + if test "x$_keys" = "xfiltered" ; then + cut -d" " -f-2 $OBJ/user_a.pub >> $OBJ/expect_a + fi + echo "NEXT" >> $OBJ/expect_a + fi + done + echo "FINISH" >> $OBJ/expect_a + for h in $_revhops "" ; do + echo "COMPLETE \"$h\"" >> $OBJ/expect_a + done +} + +prepare_multihop_script +cp $OBJ/user_a.pub $OBJ/authorized_keys_$USER # only one key used. + +verbose "multihop without agent" +clear_agent +prepare_multihop_expected none +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output || fail "multihop no agent ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" + +verbose "multihop agent unrestricted" +clear_agent +$SSHADD -q $OBJ/user_[abcde] +prepare_multihop_expected all +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output || fail "multihop no agent ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" + +verbose "multihop restricted" +clear_agent +prepare_multihop_expected filtered +# Add user_a, with permission to connect through the whole chain. +$SSHADD -h host_a -h "host_a>host_b" -h "host_b>host_c" \ + -h "host_c>host_d" -h "host_d>host_e" \ + -H $OBJ/known_hosts -q $OBJ/user_a \ + || fatal "add key user_a multihop" +# Add the other keys, bound to a unused host. +$SSHADD -q -h host_x -H $OBJ/known_hosts $OBJ/user_[bcde] || fail "add keys" +hide_privatekeys +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output || fail "multihop ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" +restore_privatekeys + +verbose "multihop username" +$SSHADD -h host_a -h "host_a>${USER}@host_b" -h "host_b>${USER}@host_c" \ + -h "host_c>${USER}@host_d" -h "host_d>${USER}@host_e" \ + -H $OBJ/known_hosts -q $OBJ/user_a || fatal "add key user_a multihop" +hide_privatekeys +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output || fail "multihop w/ user ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" +restore_privatekeys + +verbose "multihop wildcard username" +$SSHADD -h host_a -h "host_a>*@host_b" -h "host_b>*@host_c" \ + -h "host_c>*@host_d" -h "host_d>*@host_e" \ + -H $OBJ/known_hosts -q $OBJ/user_a || fatal "add key user_a multihop" +hide_privatekeys +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output || fail "multihop w/ user ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" +restore_privatekeys + +verbose "multihop wrong username" +$SSHADD -h host_a -h "host_a>*@host_b" -h "host_b>*@host_c" \ + -h "host_c>--BADUSER@host_d" -h "host_d>*@host_e" \ + -H $OBJ/known_hosts -q $OBJ/user_a || fatal "add key user_a multihop" +hide_privatekeys +$MULTIHOP_RUN "" a b c d e > $OBJ/ssh_output && \ + fail "multihop with wrong user succeeded unexpectedly" +restore_privatekeys + +verbose "multihop cycle no agent" +clear_agent +prepare_multihop_expected none "a b a a c d e" +$MULTIHOP_RUN "" a b a a c d e > $OBJ/ssh_output || \ + fail "multihop cycle no-agent fail" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" + +verbose "multihop cycle agent unrestricted" +clear_agent +$SSHADD -q $OBJ/user_[abcde] || fail "add keys" +prepare_multihop_expected all "a b a a c d e" +$MULTIHOP_RUN "" a b a a c d e > $OBJ/ssh_output || \ + fail "multihop cycle agent ssh failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" + +verbose "multihop cycle restricted deny" +clear_agent +$SSHADD -q -h host_x -H $OBJ/known_hosts $OBJ/user_[bcde] || fail "add keys" +$SSHADD -h host_a -h "host_a>host_b" -h "host_b>host_c" \ + -h "host_c>host_d" -h "host_d>host_e" \ + -H $OBJ/known_hosts -q $OBJ/user_a \ + || fatal "add key user_a multihop" +prepare_multihop_expected filtered "a b a a c d e" +hide_privatekeys +$MULTIHOP_RUN "" a b a a c d e > $OBJ/ssh_output && \ + fail "multihop cycle restricted deny succeded unexpectedly" +restore_privatekeys + +verbose "multihop cycle restricted allow" +clear_agent +$SSHADD -q -h host_x -H $OBJ/known_hosts $OBJ/user_[bcde] || fail "add keys" +$SSHADD -h host_a -h "host_a>host_b" -h "host_b>host_c" \ + -h "host_c>host_d" -h "host_d>host_e" \ + -h "host_b>host_a" -h "host_a>host_a" -h "host_a>host_c" \ + -H $OBJ/known_hosts -q $OBJ/user_a \ + || fatal "add key user_a multihop" +prepare_multihop_expected filtered "a b a a c d e" +hide_privatekeys +$MULTIHOP_RUN "" a b a a c d e > $OBJ/ssh_output || \ + fail "multihop cycle restricted allow failed" +diff $OBJ/ssh_output $OBJ/expect_a || fail "unexpected ssh output" +restore_privatekeys + -- cgit v1.2.3