# $OpenBSD: principals-command.sh,v 1.3 2016/09/26 21:34:38 bluhm Exp $ # Placed in the Public Domain. tid="authorized principals command" rm -f $OBJ/user_ca_key* $OBJ/cert_user_key* cp $OBJ/sshd_proxy $OBJ/sshd_proxy_bak if [ -z "$SUDO" -a ! -w /var/run ]; then fatal "need SUDO to create file in /var/run, test won't work without" fi SERIAL=$$ # Create a CA key and a user certificate. ${SSHKEYGEN} -q -N '' -t ed25519 -f $OBJ/user_ca_key || \ fatal "ssh-keygen of user_ca_key failed" ${SSHKEYGEN} -q -N '' -t rsa -f $OBJ/cert_user_key || \ fatal "ssh-keygen of cert_user_key failed" ${SSHKEYGEN} -q -s $OBJ/user_ca_key -I "Joanne User" \ -z $$ -n ${USER},mekmitasdigoat $OBJ/cert_user_key || \ fatal "couldn't sign cert_user_key" CERT_BODY=`cat $OBJ/cert_user_key-cert.pub | awk '{ print $2 }'` CA_BODY=`cat $OBJ/user_ca_key.pub | awk '{ print $2 }'` CERT_FP=`${SSHKEYGEN} -lf $OBJ/cert_user_key-cert.pub | awk '{ print $2 }'` CA_FP=`${SSHKEYGEN} -lf $OBJ/user_ca_key.pub | awk '{ print $2 }'` # Establish a AuthorizedPrincipalsCommand in /var/run where it will have # acceptable directory permissions. PRINCIPALS_COMMAND="/var/run/principals_command_${LOGNAME}" cat << _EOF | $SUDO sh -c "cat > '$PRINCIPALS_COMMAND'" #!/bin/sh test "x\$1" != "x${LOGNAME}" && exit 1 test "x\$2" != "xssh-rsa-cert-v01@openssh.com" && exit 1 test "x\$3" != "xssh-ed25519" && exit 1 test "x\$4" != "xJoanne User" && exit 1 test "x\$5" != "x${SERIAL}" && exit 1 test "x\$6" != "x${CA_FP}" && exit 1 test "x\$7" != "x${CERT_FP}" && exit 1 test "x\$8" != "x${CERT_BODY}" && exit 1 test "x\$9" != "x${CA_BODY}" && exit 1 test -f "$OBJ/authorized_principals_${LOGNAME}" && exec cat "$OBJ/authorized_principals_${LOGNAME}" _EOF test $? -eq 0 || fatal "couldn't prepare principals command" $SUDO chmod 0755 "$PRINCIPALS_COMMAND" # Test explicitly-specified principals for privsep in yes no ; do _prefix="privsep $privsep" # Setup for AuthorizedPrincipalsCommand rm -f $OBJ/authorized_keys_$USER ( cat $OBJ/sshd_proxy_bak echo "UsePrivilegeSeparation $privsep" echo "AuthorizedKeysFile none" echo "AuthorizedPrincipalsCommand $PRINCIPALS_COMMAND" \ "%u %t %T %i %s %F %f %k %K" echo "AuthorizedPrincipalsCommandUser ${LOGNAME}" echo "TrustedUserCAKeys $OBJ/user_ca_key.pub" ) > $OBJ/sshd_proxy # XXX test missing command # XXX test failing command # Empty authorized_principals verbose "$tid: ${_prefix} empty authorized_principals" echo > $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -eq 0 ]; then fail "ssh cert connect succeeded unexpectedly" fi # Wrong authorized_principals verbose "$tid: ${_prefix} wrong authorized_principals" echo gregorsamsa > $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -eq 0 ]; then fail "ssh cert connect succeeded unexpectedly" fi # Correct authorized_principals verbose "$tid: ${_prefix} correct authorized_principals" echo mekmitasdigoat > $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -ne 0 ]; then fail "ssh cert connect failed" fi # authorized_principals with bad key option verbose "$tid: ${_prefix} authorized_principals bad key opt" echo 'blah mekmitasdigoat' > $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -eq 0 ]; then fail "ssh cert connect succeeded unexpectedly" fi # authorized_principals with command=false verbose "$tid: ${_prefix} authorized_principals command=false" echo 'command="false" mekmitasdigoat' > \ $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -eq 0 ]; then fail "ssh cert connect succeeded unexpectedly" fi # authorized_principals with command=true verbose "$tid: ${_prefix} authorized_principals command=true" echo 'command="true" mekmitasdigoat' > \ $OBJ/authorized_principals_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost false >/dev/null 2>&1 if [ $? -ne 0 ]; then fail "ssh cert connect failed" fi # Setup for principals= key option rm -f $OBJ/authorized_principals_$USER ( cat $OBJ/sshd_proxy_bak echo "UsePrivilegeSeparation $privsep" ) > $OBJ/sshd_proxy # Wrong principals list verbose "$tid: ${_prefix} wrong principals key option" ( printf 'cert-authority,principals="gregorsamsa" ' cat $OBJ/user_ca_key.pub ) > $OBJ/authorized_keys_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -eq 0 ]; then fail "ssh cert connect succeeded unexpectedly" fi # Correct principals list verbose "$tid: ${_prefix} correct principals key option" ( printf 'cert-authority,principals="mekmitasdigoat" ' cat $OBJ/user_ca_key.pub ) > $OBJ/authorized_keys_$USER ${SSH} -2i $OBJ/cert_user_key \ -F $OBJ/ssh_proxy somehost true >/dev/null 2>&1 if [ $? -ne 0 ]; then fail "ssh cert connect failed" fi done