diff --git a/contrib/util/check-config.sh b/contrib/util/check-config.sh new file mode 100755 index 0000000000..52e01aa8eb --- /dev/null +++ b/contrib/util/check-config.sh @@ -0,0 +1,363 @@ +#!/usr/bin/env bash +set -e + +EXITCODE=0 + +# bits of this were adapted from lxc-checkconfig +# see also https://github.com/lxc/lxc/blob/lxc-1.0.2/src/lxc/lxc-checkconfig.in + +possibleConfigs=( + '/proc/config.gz' + "/boot/config-$(uname -r)" + "/usr/src/linux-$(uname -r)/.config" + '/usr/src/linux/.config' +) + +if [ $# -gt 0 ]; then + CONFIG="$1" +else + : "${CONFIG:="${possibleConfigs[0]}"}" +fi + +if ! command -v zgrep &> /dev/null; then + zgrep() { + zcat "$2" | grep "$1" + } +fi + +kernelVersion="$(uname -r)" +kernelMajor="${kernelVersion%%.*}" +kernelMinor="${kernelVersion#$kernelMajor.}" +kernelMinor="${kernelMinor%%.*}" + +is_set() { + zgrep "CONFIG_$1=[y|m]" "$CONFIG" > /dev/null +} +is_set_in_kernel() { + zgrep "CONFIG_$1=y" "$CONFIG" > /dev/null +} +is_set_as_module() { + zgrep "CONFIG_$1=m" "$CONFIG" > /dev/null +} + +color() { + local codes=() + if [ "$1" = 'bold' ]; then + codes=( "${codes[@]}" '1' ) + shift + fi + if [ "$#" -gt 0 ]; then + local code= + case "$1" in + # see https://en.wikipedia.org/wiki/ANSI_escape_code#Colors + black) code=30 ;; + red) code=31 ;; + green) code=32 ;; + yellow) code=33 ;; + blue) code=34 ;; + magenta) code=35 ;; + cyan) code=36 ;; + white) code=37 ;; + esac + if [ "$code" ]; then + codes=( "${codes[@]}" "$code" ) + fi + fi + local IFS=';' + echo -en '\033['"${codes[*]}"'m' +} +wrap_color() { + text="$1" + shift + color "$@" + echo -n "$text" + color reset + echo +} + +wrap_good() { + echo "$(wrap_color "$1" white): $(wrap_color "$2" green)" +} +wrap_bad() { + echo "$(wrap_color "$1" bold): $(wrap_color "$2" bold red)" +} +wrap_warning() { + wrap_color >&2 "$*" red +} + +check_flag() { + if is_set_in_kernel "$1"; then + wrap_good "CONFIG_$1" 'enabled' + elif is_set_as_module "$1"; then + wrap_good "CONFIG_$1" 'enabled (as module)' + else + wrap_bad "CONFIG_$1" 'missing' + EXITCODE=1 + fi +} + +check_flags() { + for flag in "$@"; do + echo -n "- "; check_flag "$flag" + done +} + +check_command() { + if command -v "$1" >/dev/null 2>&1; then + wrap_good "$1 command" 'available' + else + wrap_bad "$1 command" 'missing' + EXITCODE=1 + fi +} + +check_device() { + if [ -c "$1" ]; then + wrap_good "$1" 'present' + else + wrap_bad "$1" 'missing' + EXITCODE=1 + fi +} + +check_distro_userns() { + source /etc/os-release 2>/dev/null || /bin/true + if [[ "${ID}" =~ ^(centos|rhel)$ && "${VERSION_ID}" =~ ^7 ]]; then + # this is a CentOS7 or RHEL7 system + grep -q "user_namespace.enable=1" /proc/cmdline || { + # no user namespace support enabled + wrap_bad " (RHEL7/CentOS7" "User namespaces disabled; add 'user_namespace.enable=1' to boot command line)" + EXITCODE=1 + } + fi +} + +if [ ! -e "$CONFIG" ]; then + wrap_warning "warning: $CONFIG does not exist, searching other paths for kernel config ..." + for tryConfig in "${possibleConfigs[@]}"; do + if [ -e "$tryConfig" ]; then + CONFIG="$tryConfig" + break + fi + done + if [ ! -e "$CONFIG" ]; then + wrap_warning "error: cannot find kernel config" + wrap_warning " try running this script again, specifying the kernel config:" + wrap_warning " CONFIG=/path/to/kernel/.config $0 or $0 /path/to/kernel/.config" + exit 1 + fi +fi + +wrap_color "info: reading kernel config from $CONFIG ..." white +echo + +echo 'Generally Necessary:' + +echo -n '- ' +cgroupSubsystemDir="$(awk '/[, ](cpu|cpuacct|cpuset|devices|freezer|memory)[, ]/ && $3 == "cgroup" { print $2 }' /proc/mounts | head -n1)" +cgroupDir="$(dirname "$cgroupSubsystemDir")" +if [ -d "$cgroupDir/cpu" ] || [ -d "$cgroupDir/cpuacct" ] || [ -d "$cgroupDir/cpuset" ] || [ -d "$cgroupDir/devices" ] || [ -d "$cgroupDir/freezer" ] || [ -d "$cgroupDir/memory" ]; then + echo "$(wrap_good 'cgroup hierarchy' 'properly mounted') [$cgroupDir]" +else + if [ "$cgroupSubsystemDir" ]; then + echo "$(wrap_bad 'cgroup hierarchy' 'single mountpoint!') [$cgroupSubsystemDir]" + else + wrap_bad 'cgroup hierarchy' 'nonexistent??' + fi + EXITCODE=1 + echo " $(wrap_color '(see https://github.com/tianon/cgroupfs-mount)' yellow)" +fi + +if [ "$(cat /sys/module/apparmor/parameters/enabled 2>/dev/null)" = 'Y' ]; then + echo -n '- ' + if command -v apparmor_parser &> /dev/null; then + wrap_good 'apparmor' 'enabled and tools installed' + else + wrap_bad 'apparmor' 'enabled, but apparmor_parser missing' + echo -n ' ' + if command -v apt-get &> /dev/null; then + wrap_color '(use "apt-get install apparmor" to fix this)' + elif command -v yum &> /dev/null; then + wrap_color '(your best bet is "yum install apparmor-parser")' + else + wrap_color '(look for an "apparmor" package for your distribution)' + fi + EXITCODE=1 + fi +fi + +flags=( + NAMESPACES {NET,PID,IPC,UTS}_NS + CGROUPS CGROUP_CPUACCT CGROUP_DEVICE CGROUP_FREEZER CGROUP_SCHED CPUSETS MEMCG + KEYS + VETH BRIDGE BRIDGE_NETFILTER + NF_NAT_IPV4 IP_NF_FILTER IP_NF_TARGET_MASQUERADE + NETFILTER_XT_MATCH_{ADDRTYPE,CONNTRACK,IPVS} + IP_NF_NAT NF_NAT NF_NAT_NEEDED + + # required for bind-mounting /dev/mqueue into containers + POSIX_MQUEUE +) +check_flags "${flags[@]}" +if [ "$kernelMajor" -lt 4 ] || ( [ "$kernelMajor" -eq 4 ] && [ "$kernelMinor" -lt 8 ] ); then + check_flags DEVPTS_MULTIPLE_INSTANCES +fi + +echo + +echo 'Optional Features:' +{ + check_flags USER_NS + check_distro_userns +} +{ + check_flags SECCOMP +} +{ + check_flags CGROUP_PIDS +} +{ + CODE=${EXITCODE} + check_flags MEMCG_SWAP MEMCG_SWAP_ENABLED + if [ -e /sys/fs/cgroup/memory/memory.memsw.limit_in_bytes ]; then + echo " $(wrap_color '(cgroup swap accounting is currently enabled)' bold black)" + EXITCODE=${CODE} + elif is_set MEMCG_SWAP && ! is_set MEMCG_SWAP_ENABLED; then + echo " $(wrap_color '(cgroup swap accounting is currently not enabled, you can enable it by setting boot option "swapaccount=1")' bold black)" + fi +} +{ + if is_set LEGACY_VSYSCALL_NATIVE; then + echo -n "- "; wrap_bad "CONFIG_LEGACY_VSYSCALL_NATIVE" 'enabled' + echo " $(wrap_color '(dangerous, provides an ASLR-bypassing target with usable ROP gadgets.)' bold black)" + elif is_set LEGACY_VSYSCALL_EMULATE; then + echo -n "- "; wrap_good "CONFIG_LEGACY_VSYSCALL_EMULATE" 'enabled' + elif is_set LEGACY_VSYSCALL_NONE; then + echo -n "- "; wrap_bad "CONFIG_LEGACY_VSYSCALL_NONE" 'enabled' + echo " $(wrap_color '(containers using eglibc <= 2.13 will not work. Switch to' bold black)" + echo " $(wrap_color ' "CONFIG_VSYSCALL_[NATIVE|EMULATE]" or use "vsyscall=[native|emulate]"' bold black)" + echo " $(wrap_color ' on kernel command line. Note that this will disable ASLR for the,' bold black)" + echo " $(wrap_color ' VDSO which may assist in exploiting security vulnerabilities.)' bold black)" + # else Older kernels (prior to 3dc33bd30f3e, released in v4.40-rc1) do + # not have these LEGACY_VSYSCALL options and are effectively + # LEGACY_VSYSCALL_EMULATE. Even older kernels are presumably + # effectively LEGACY_VSYSCALL_NATIVE. + fi +} + +if [ "$kernelMajor" -lt 4 ] || ( [ "$kernelMajor" -eq 4 ] && [ "$kernelMinor" -le 5 ] ); then + check_flags MEMCG_KMEM +fi + +if [ "$kernelMajor" -lt 3 ] || ( [ "$kernelMajor" -eq 3 ] && [ "$kernelMinor" -le 18 ] ); then + check_flags RESOURCE_COUNTERS +fi + +if [ "$kernelMajor" -lt 3 ] || ( [ "$kernelMajor" -eq 3 ] && [ "$kernelMinor" -le 13 ] ); then + netprio=NETPRIO_CGROUP +else + netprio=CGROUP_NET_PRIO +fi + +flags=( + BLK_CGROUP BLK_DEV_THROTTLING IOSCHED_CFQ CFQ_GROUP_IOSCHED + CGROUP_PERF + CGROUP_HUGETLB + NET_CLS_CGROUP $netprio + CFS_BANDWIDTH FAIR_GROUP_SCHED RT_GROUP_SCHED + IP_NF_TARGET_REDIRECT + IP_VS + IP_VS_NFCT + IP_VS_PROTO_TCP + IP_VS_PROTO_UDP + IP_VS_RR +) +check_flags "${flags[@]}" + +if ! is_set EXT4_USE_FOR_EXT2; then + check_flags EXT3_FS EXT3_FS_XATTR EXT3_FS_POSIX_ACL EXT3_FS_SECURITY + if ! is_set EXT3_FS || ! is_set EXT3_FS_XATTR || ! is_set EXT3_FS_POSIX_ACL || ! is_set EXT3_FS_SECURITY; then + echo " $(wrap_color '(enable these ext3 configs if you are using ext3 as backing filesystem)' bold black)" + fi +fi + +check_flags EXT4_FS EXT4_FS_POSIX_ACL EXT4_FS_SECURITY +if ! is_set EXT4_FS || ! is_set EXT4_FS_POSIX_ACL || ! is_set EXT4_FS_SECURITY; then + if is_set EXT4_USE_FOR_EXT2; then + echo " $(wrap_color 'enable these ext4 configs if you are using ext3 or ext4 as backing filesystem' bold black)" + else + echo " $(wrap_color 'enable these ext4 configs if you are using ext4 as backing filesystem' bold black)" + fi +fi + +echo '- Network Drivers:' +echo " - \"$(wrap_color 'overlay' blue)\":" +check_flags VXLAN BRIDGE_VLAN_FILTERING | sed 's/^/ /' +echo ' Optional (for encrypted networks):' +check_flags CRYPTO CRYPTO_AEAD CRYPTO_GCM CRYPTO_SEQIV CRYPTO_GHASH \ + XFRM XFRM_USER XFRM_ALGO INET_ESP INET_XFRM_MODE_TRANSPORT | sed 's/^/ /' +echo " - \"$(wrap_color 'ipvlan' blue)\":" +check_flags IPVLAN | sed 's/^/ /' +echo " - \"$(wrap_color 'macvlan' blue)\":" +check_flags MACVLAN DUMMY | sed 's/^/ /' +echo " - \"$(wrap_color 'ftp,tftp client in container' blue)\":" +check_flags NF_NAT_FTP NF_CONNTRACK_FTP NF_NAT_TFTP NF_CONNTRACK_TFTP | sed 's/^/ /' + +# only fail if no storage drivers available +CODE=${EXITCODE} +EXITCODE=0 +STORAGE=1 + +echo '- Storage Drivers:' +echo " - \"$(wrap_color 'aufs' blue)\":" +check_flags AUFS_FS | sed 's/^/ /' +if ! is_set AUFS_FS && grep -q aufs /proc/filesystems; then + echo " $(wrap_color '(note that some kernels include AUFS patches but not the AUFS_FS flag)' bold black)" +fi +[ "$EXITCODE" = 0 ] && STORAGE=0 +EXITCODE=0 + +echo " - \"$(wrap_color 'btrfs' blue)\":" +check_flags BTRFS_FS | sed 's/^/ /' +check_flags BTRFS_FS_POSIX_ACL | sed 's/^/ /' +[ "$EXITCODE" = 0 ] && STORAGE=0 +EXITCODE=0 + +echo " - \"$(wrap_color 'devicemapper' blue)\":" +check_flags BLK_DEV_DM DM_THIN_PROVISIONING | sed 's/^/ /' +[ "$EXITCODE" = 0 ] && STORAGE=0 +EXITCODE=0 + +echo " - \"$(wrap_color 'overlay' blue)\":" +check_flags OVERLAY_FS | sed 's/^/ /' +[ "$EXITCODE" = 0 ] && STORAGE=0 +EXITCODE=0 + +echo " - \"$(wrap_color 'zfs' blue)\":" +echo -n " - "; check_device /dev/zfs +echo -n " - "; check_command zfs +echo -n " - "; check_command zpool +[ "$EXITCODE" = 0 ] && STORAGE=0 +EXITCODE=0 + +EXITCODE=$CODE +[ "$STORAGE" = 1 ] && EXITCODE=1 + +echo + +check_limit_over() +{ + if [ "$(cat "$1")" -le "$2" ]; then + wrap_bad "- $1" "$(cat "$1")" + wrap_color " This should be set to at least $2, for example set: sysctl -w kernel/keys/root_maxkeys=1000000" bold black + EXITCODE=1 + else + wrap_good "- $1" "$(cat "$1")" + fi +} + +echo 'Limits:' +check_limit_over /proc/sys/kernel/keys/root_maxkeys 10000 +echo + +exit $EXITCODE