commit 5469297999a177996230f208ab5d5de30df7376f
Author: luisgulo <luisgulo@noreply.localhost>
Date:   Tue Nov 7 16:24:20 2023 +0100

    check .config kernel para Docker
    
    Script para comprobar fichero .config para compilar Kernel con soporte para Docker y Docker Swarm

diff --git a/check-config.sh b/check-config.sh
new file mode 100644
index 0000000..7f57c7b
--- /dev/null
+++ b/check-config.sh
@@ -0,0 +1,411 @@
+#!/usr/bin/env sh
+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:=/proc/config.gz}"
+fi
+
+if ! command -v zgrep > /dev/null 2>&1; 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() {
+	codes=
+	if [ "$1" = 'bold' ]; then
+		codes='1'
+		shift
+	fi
+	if [ "$#" -gt 0 ]; then
+		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="${codes:+$codes;}$code"
+		fi
+	fi
+	printf '\033[%sm' "$codes"
+}
+wrap_color() {
+	text="$1"
+	shift
+	color "$@"
+	printf '%s' "$text"
+	color reset
+	echo
+}
+
+wrap_good() {
+	echo "$(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
+		printf -- '- '
+		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 "$1" 'missing'
+		EXITCODE=1
+	fi
+}
+
+check_distro_userns() {
+	if [ ! -e /etc/os-release ]; then
+		return
+	fi
+	. /etc/os-release 2> /dev/null || /bin/true
+	case "$ID" in
+		centos | rhel)
+			case "$VERSION_ID" in
+				7*)
+					# this is a CentOS7 or RHEL7 system
+					grep -q 'user_namespace.enable=1' /proc/cmdline || {
+						# no user namespace support enabled
+						wrap_bad "  (RHEL7/CentOS7" "User namespaces disabled; add 'user_namespace.enable=1' to boot command line)"
+						EXITCODE=1
+					}
+					;;
+			esac
+			;;
+	esac
+}
+
+if [ ! -e "$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 $CONFIG ..." white
+echo
+
+echo 'Generally Necessary:'
+
+printf -- '- '
+if [ "$(stat -f -c %t /sys/fs/cgroup 2> /dev/null)" = '63677270' ]; then
+	wrap_good 'cgroup hierarchy' 'cgroupv2'
+	cgroupv2ControllerFile='/sys/fs/cgroup/cgroup.controllers'
+	if [ -f "$cgroupv2ControllerFile" ]; then
+		echo '  Controllers:'
+		for controller in cpu cpuset io memory pids; do
+			if grep -qE '(^| )'"$controller"'($| )' "$cgroupv2ControllerFile"; then
+				echo "  - $(wrap_good "$controller" 'available')"
+			else
+				echo "  - $(wrap_bad "$controller" 'missing')"
+			fi
+		done
+	else
+		wrap_bad "$cgroupv2ControllerFile" 'nonexistent??'
+	fi
+	# TODO find an efficient way to check if cgroup.freeze exists in subdir
+else
+	cgroupSubsystemDir="$(sed -rne '/^[^ ]+ ([^ ]+) cgroup ([^ ]*,)?(cpu|cpuacct|cpuset|devices|freezer|memory)[, ].*$/ { s//\1/p; q }' /proc/mounts)"
+	cgroupDir="$(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 "    $(wrap_color '(see https://github.com/tianon/cgroupfs-mount)' yellow)"
+	fi
+fi
+
+if [ "$(cat /sys/module/apparmor/parameters/enabled 2> /dev/null)" = 'Y' ]; then
+	printf -- '- '
+	if command -v apparmor_parser > /dev/null 2>&1; then
+		wrap_good 'apparmor' 'enabled and tools installed'
+	else
+		wrap_bad 'apparmor' 'enabled, but apparmor_parser missing'
+		printf '    '
+		if command -v apt-get > /dev/null 2>&1; then
+			wrap_color '(use "apt-get install apparmor" to fix this)'
+		elif command -v yum > /dev/null 2>&1; 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
+
+check_flags \
+	NAMESPACES NET_NS PID_NS IPC_NS UTS_NS \
+	CGROUPS CGROUP_CPUACCT CGROUP_DEVICE CGROUP_FREEZER CGROUP_SCHED CPUSETS MEMCG \
+	KEYS \
+	VETH BRIDGE BRIDGE_NETFILTER \
+	IP_NF_FILTER IP_NF_MANGLE IP_NF_TARGET_MASQUERADE \
+	NETFILTER_XT_MATCH_ADDRTYPE \
+	NETFILTER_XT_MATCH_CONNTRACK \
+	NETFILTER_XT_MATCH_IPVS \
+	NETFILTER_XT_MARK \
+	IP_NF_NAT NF_NAT \
+	POSIX_MQUEUE
+# (POSIX_MQUEUE is required for bind-mounting /dev/mqueue into containers)
+
+if [ "$kernelMajor" -lt 4 ] || ([ "$kernelMajor" -eq 4 ] && [ "$kernelMinor" -lt 8 ]); then
+	check_flags DEVPTS_MULTIPLE_INSTANCES
+fi
+
+if [ "$kernelMajor" -lt 5 ] || [ "$kernelMajor" -eq 5 -a "$kernelMinor" -le 1 ]; then
+	check_flags NF_NAT_IPV4
+fi
+
+if [ "$kernelMajor" -lt 5 ] || [ "$kernelMajor" -eq 5 -a "$kernelMinor" -le 2 ]; then
+	check_flags NF_NAT_NEEDED
+fi
+# check availability of BPF_CGROUP_DEVICE support
+if [ "$kernelMajor" -ge 5 ] || ([ "$kernelMajor" -eq 4 ] && [ "$kernelMinor" -ge 15 ]); then
+	check_flags CGROUP_BPF
+fi
+
+echo
+
+echo 'Optional Features:'
+{
+	check_flags USER_NS
+	check_distro_userns
+}
+{
+	check_flags SECCOMP
+	check_flags SECCOMP_FILTER
+}
+{
+	check_flags CGROUP_PIDS
+}
+{
+	check_flags MEMCG_SWAP
+	# Kernel v5.8+ removes MEMCG_SWAP_ENABLED.
+	if [ "$kernelMajor" -lt 5 ] || [ "$kernelMajor" -eq 5 -a "$kernelMinor" -le 8 ]; then
+		CODE=${EXITCODE}
+		check_flags MEMCG_SWAP_ENABLED
+		# FIXME this check is cgroupv1-specific
+		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
+	else
+		# Kernel v5.8+ enables swap accounting by default.
+		echo "    $(wrap_color '(cgroup swap accounting is currently enabled)' bold black)"
+	fi
+}
+{
+	if is_set LEGACY_VSYSCALL_NATIVE; then
+		printf -- '- '
+		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
+		printf -- '- '
+		wrap_good "CONFIG_LEGACY_VSYSCALL_EMULATE" 'enabled'
+	elif is_set LEGACY_VSYSCALL_NONE; then
+		printf -- '- '
+		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
+
+if [ "$kernelMajor" -lt 5 ]; then
+	check_flags IOSCHED_CFQ CFQ_GROUP_IOSCHED
+fi
+
+check_flags \
+	BLK_CGROUP BLK_DEV_THROTTLING \
+	CGROUP_PERF \
+	CGROUP_HUGETLB \
+	NET_CLS_CGROUP $netprio \
+	CFS_BANDWIDTH FAIR_GROUP_SCHED \
+	IP_NF_TARGET_REDIRECT \
+	IP_VS \
+	IP_VS_NFCT \
+	IP_VS_PROTO_TCP \
+	IP_VS_PROTO_UDP \
+	IP_VS_RR \
+	SECURITY_SELINUX \
+	SECURITY_APPARMOR
+
+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 NETFILTER_XT_MATCH_BPF | sed 's/^/      /'
+if [ "$kernelMajor" -lt 5 ] || [ "$kernelMajor" -eq 5 -a "$kernelMinor" -le 3 ]; then
+	check_flags INET_XFRM_MODE_TRANSPORT | sed 's/^/      /'
+fi
+echo "  - \"$(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 '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 'overlay' blue)\":"
+check_flags OVERLAY_FS | sed 's/^/    /'
+[ "$EXITCODE" = 0 ] && STORAGE=0
+EXITCODE=0
+
+echo "  - \"$(wrap_color 'zfs' blue)\":"
+printf '    - '
+check_device /dev/zfs
+printf '    - '
+check_command zfs
+printf '    - '
+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