contrib/dockerd-rootless.sh - third_party/github.com/moby/moby - Git at Google

 #!/bin/sh
 # dockerd-rootless.sh executes dockerd in rootless mode.
 #
 # Usage: dockerd-rootless.sh [DOCKERD_OPTIONS]
 #
 # External dependencies:
 # * newuidmap and newgidmap needs to be installed.
 # * /etc/subuid and /etc/subgid needs to be configured for the current user.
 # * Either one of slirp4netns (>= v0.4.0), VPNKit, lxc-user-nic needs to be installed.
 #
 # Recognized environment variables:
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR=DIR: the rootlesskit state dir.
 #   * Defaults to "$XDG_RUNTIME_DIR/dockerd-rootless".
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_NET=(slirp4netns|vpnkit|pasta|lxc-user-nic): the rootlesskit network driver.
 #   * Defaults to "slirp4netns" if slirp4netns (>= v0.4.0) is installed, else "pasta", else "vpnkit".
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_MTU=NUM: the MTU value for the rootlesskit network driver.
 #   * Defaults to 65520 for slirp4netns and pasta, 1500 for other rootlesskit network drivers.
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=(builtin|slirp4netns|implicit): the rootlesskit port driver.
 #   * Defaults to "implicit" for "pasta", "builtin" for other rootlesskit network drivers.
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX=(auto|true|false): whether to protect slirp4netns with a dedicated mount namespace.
 #   * Defaults to "auto".
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP=(auto|true|false): whether to protect slirp4netns with seccomp.
 #   * Defaults to "auto".
 # * DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK=(true|false): prohibit connections to 127.0.0.1 on the host (including via 10.0.2.2, in the case of slirp4netns).
 #   * Defaults to "true".

 # To apply an environment variable via systemd, create ~/.config/systemd/user/docker.service.d/override.conf as follows,
 # and run `systemctl --user daemon-reload && systemctl --user restart docker`:
 # --- BEGIN ---
 # [Service]
 # Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_NET=pasta"
 # Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=implicit"
 # ---  END  ---

 # Guide to choose the network driver and the port driver:
 #
 #  Network driver | Port driver    | Net throughput | Port throughput | Src IP | No SUID | Note
 #  ---------------|----------------|----------------|-----------------|--------|---------|---------------------------------------------------------
 #  slirp4netns    | builtin        | Slow           | Fast ✅         | ❌     | ✅      | Default in typical setup
 #  vpnkit         | builtin        | Slow           | Fast ✅         | ❌     | ✅      | Default when slirp4netns is not installed
 #  slirp4netns    | slirp4netns    | Slow           | Slow            | ✅     | ✅      |
 #  pasta          | implicit       | Slow           | Fast ✅         | ✅     | ✅      | Experimental; Needs recent version of pasta (2023_12_04)
 #  lxc-user-nic   | builtin        | Fast ✅        | Fast ✅         | ❌     | ❌      | Experimental
 #  (bypass4netns) | (bypass4netns) | Fast ✅        | Fast ✅         | ✅     | ✅      | (Not integrated to RootlessKit)

 # See the documentation for the further information: https://docs.docker.com/go/rootless/

 set -e -x
 case "$1" in
 	"check" | "install" | "uninstall")
 		echo "Did you mean 'dockerd-rootless-setuptool.sh $@' ?"
 		exit 1
 		;;
 esac
 if ! [ -w "$XDG_RUNTIME_DIR" ]; then
 	echo "XDG_RUNTIME_DIR needs to be set and writable"
 	exit 1
 fi
 if ! [ -d "$HOME" ]; then
 	echo "HOME needs to be set and exist."
 	exit 1
 fi

 mount_directory() {
 	if [ -z "$_DOCKERD_ROOTLESS_CHILD" ]; then
 		echo "mount_directory should be called from the child context. Otherwise data loss is at risk" >&2
 		exit 1
 	fi

 	DIRECTORY="$1"
 	if [ ! -d "$DIRECTORY" ]; then
 		return
 	fi

 	# Bind mount directory: this makes this directory visible to
 	# Dockerd, even if it is originally a symlink, given Dockerd does
 	# not always follow symlinks. Some directories might also be
 	# "copied-up", meaning that they will also be writable on the child
 	# namespace; this will be the case only if they are provided as
 	# --copy-up to the rootlesskit.
 	DIRECTORY_REALPATH=$(realpath "$DIRECTORY")
 	MOUNT_OPTIONS="${2:---bind}"
 	rm -rf "$DIRECTORY"
 	mkdir -p "$DIRECTORY"
 	mount $MOUNT_OPTIONS "$DIRECTORY_REALPATH" "$DIRECTORY"
 }

 rootlesskit=""
 for f in docker-rootlesskit rootlesskit; do
 	if command -v $f > /dev/null 2>&1; then
 		rootlesskit=$f
 		break
 	fi
 done
 if [ -z "$rootlesskit" ]; then
 	echo "rootlesskit needs to be installed"
 	exit 1
 fi

 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR:=$XDG_RUNTIME_DIR/dockerd-rootless}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_NET:=}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_MTU:=}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER:=}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX:=auto}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP:=auto}"
 : "${DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK:=}"
 net=$DOCKERD_ROOTLESS_ROOTLESSKIT_NET
 port_driver=$DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER
 mtu=$DOCKERD_ROOTLESS_ROOTLESSKIT_MTU
 if [ -z "$net" ]; then
 	if command -v slirp4netns > /dev/null 2>&1; then
 		# If --netns-type is present in --help, slirp4netns is >= v0.4.0.
 		if slirp4netns --help | grep -qw -- --netns-type; then
 			net=slirp4netns
 		else
 			echo "slirp4netns found but seems older than v0.4.0. Checking for other network drivers."
 		fi
 	fi
 	if [ -z "$net" ]; then
 		if command -v pasta > /dev/null 2>&1; then
 			net=pasta
 		fi
 	fi
 	if [ -z "$net" ]; then
 		if command -v vpnkit > /dev/null 2>&1; then
 			net=vpnkit
 		fi
 	fi
 	if [ -z "$net" ]; then
 		echo "One of slirp4netns (>= v0.4.0), pasta (passt >= 2023_12_04), or vpnkit needs to be installed"
 	fi
 fi
 if [ "$net" = host ]; then
 	echo "Unsupported RootlessKit network driver: $net"
 	exit 1
 fi
 if [ -z "$mtu" ]; then
 	if [ "$net" = slirp4netns -o "$net" = pasta ]; then
 		mtu=65520
 	else
 		mtu=1500
 	fi
 fi
 if [ -z "$port_driver" ]; then
 	if [ "$net" = pasta ]; then
 		port_driver=implicit
 	else
 		port_driver=builtin
 	fi
 fi

 host_loopback="--disable-host-loopback"
 if [ "$DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK" = "false" ]; then
 	host_loopback=""
 fi

 dockerd="${DOCKERD:-dockerd}"

 if [ -z "$_DOCKERD_ROOTLESS_CHILD" ]; then
 	_DOCKERD_ROOTLESS_CHILD=1
 	export _DOCKERD_ROOTLESS_CHILD
 	if [ "$(id -u)" = "0" ]; then
 		echo "This script must be executed as a non-privileged user"
 		exit 1
 	fi
 	# `selinuxenabled` always returns false in RootlessKit child, so we execute `selinuxenabled` in the parent.
 	# https://github.com/rootless-containers/rootlesskit/issues/94
 	if command -v selinuxenabled > /dev/null 2>&1 && selinuxenabled; then
 		_DOCKERD_ROOTLESS_SELINUX=1
 		export _DOCKERD_ROOTLESS_SELINUX
 	fi
 	# Re-exec the script via RootlessKit, so as to create unprivileged {user,mount,network} namespaces.
 	#
 	# --copy-up allows removing/creating files in the directories by creating tmpfs and symlinks
 	# * /etc: copy-up is required so as to prevent `/etc/resolv.conf` in the
 	#         namespace from being unexpectedly unmounted when `/etc/resolv.conf` is recreated on the host
 	#         (by either systemd-networkd or NetworkManager)
 	# * /run: copy-up is required so that we can create /run/docker (hardcoded for plugins) in our namespace
 	exec $rootlesskit \
 		--state-dir=$DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR \
 		--net=$net --mtu=$mtu \
 		--slirp4netns-sandbox=$DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX \
 		--slirp4netns-seccomp=$DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP \
 		$host_loopback --port-driver=$port_driver \
 		--copy-up=/etc --copy-up=/run \
 		--propagation=rslave \
 		$DOCKERD_ROOTLESS_ROOTLESSKIT_FLAGS \
 		"$0" "$@"
 else
 	[ "$_DOCKERD_ROOTLESS_CHILD" = 1 ]

 	# The Container Device Interface (CDI) specs can be found by default
 	# under {/etc,/var/run}/cdi. More information at:
 	# https://github.com/cncf-tags/container-device-interface
 	#
 	# In order to use the Container Device Interface (CDI) integration,
 	# the CDI paths need to exist before the Docker daemon is started in
 	# order for it to read the CDI specification files. Otherwise, a
 	# Docker daemon restart will be required for the daemon to discover
 	# them.
 	#
 	# If another set of CDI paths (other than the default /etc/cdi and
 	# /var/run/cdi) are configured through the Docker configuration file
 	# (using "cdi-spec-dirs"), they need to be bind mounted in rootless
 	# mode; otherwise the Docker daemon won't have access to the CDI
 	# specification files.
 	mount_directory /etc/cdi
 	mount_directory /var/run/cdi

 	# remove the symlinks for the existing files in the parent namespace if any,
 	# so that we can create our own files in our mount namespace.
 	rm -f /run/docker /run/containerd /run/xtables.lock

 	if [ -n "$_DOCKERD_ROOTLESS_SELINUX" ]; then
 		# iptables requires /run in the child to be relabeled. The actual /run in the parent is unaffected.
 		# https://github.com/containers/podman/blob/e6fc34b71aa9d876b1218efe90e14f8b912b0603/libpod/networking_linux.go#L396-L401
 		# https://github.com/moby/moby/issues/41230
 		chcon system_u:object_r:iptables_var_run_t:s0 /run
 	fi

 	if [ "$(stat -c %T -f /etc)" = "tmpfs" ] && [ -L "/etc/ssl" ]; then
 		# Workaround for "x509: certificate signed by unknown authority" on openSUSE Tumbleweed.
 		# https://github.com/rootless-containers/rootlesskit/issues/225
 		mount_directory /etc/ssl "--rbind"
 	fi

 	exec "$dockerd" "$@"
 fi
	#!/bin/sh
	# dockerd-rootless.sh executes dockerd in rootless mode.
	#
	# Usage: dockerd-rootless.sh [DOCKERD_OPTIONS]
	#
	# External dependencies:
	# * newuidmap and newgidmap needs to be installed.
	# * /etc/subuid and /etc/subgid needs to be configured for the current user.
	# * Either one of slirp4netns (>= v0.4.0), VPNKit, lxc-user-nic needs to be installed.
	#
	# Recognized environment variables:
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR=DIR: the rootlesskit state dir.
	# * Defaults to "$XDG_RUNTIME_DIR/dockerd-rootless".
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_NET=(slirp4netns\|vpnkit\|pasta\|lxc-user-nic): the rootlesskit network driver.
	# * Defaults to "slirp4netns" if slirp4netns (>= v0.4.0) is installed, else "pasta", else "vpnkit".
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_MTU=NUM: the MTU value for the rootlesskit network driver.
	# * Defaults to 65520 for slirp4netns and pasta, 1500 for other rootlesskit network drivers.
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=(builtin\|slirp4netns\|implicit): the rootlesskit port driver.
	# * Defaults to "implicit" for "pasta", "builtin" for other rootlesskit network drivers.
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX=(auto\|true\|false): whether to protect slirp4netns with a dedicated mount namespace.
	# * Defaults to "auto".
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP=(auto\|true\|false): whether to protect slirp4netns with seccomp.
	# * Defaults to "auto".
	# * DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK=(true\|false): prohibit connections to 127.0.0.1 on the host (including via 10.0.2.2, in the case of slirp4netns).
	# * Defaults to "true".

	# To apply an environment variable via systemd, create ~/.config/systemd/user/docker.service.d/override.conf as follows,
	# and run `systemctl --user daemon-reload && systemctl --user restart docker`:
	# --- BEGIN ---
	# [Service]
	# Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_NET=pasta"
	# Environment="DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER=implicit"
	# --- END ---

	# Guide to choose the network driver and the port driver:
	#
	# Network driver \| Port driver \| Net throughput \| Port throughput \| Src IP \| No SUID \| Note
	# ---------------\|----------------\|----------------\|-----------------\|--------\|---------\|---------------------------------------------------------
	# slirp4netns \| builtin \| Slow \| Fast ✅ \| ❌ \| ✅ \| Default in typical setup
	# vpnkit \| builtin \| Slow \| Fast ✅ \| ❌ \| ✅ \| Default when slirp4netns is not installed
	# slirp4netns \| slirp4netns \| Slow \| Slow \| ✅ \| ✅ \|
	# pasta \| implicit \| Slow \| Fast ✅ \| ✅ \| ✅ \| Experimental; Needs recent version of pasta (2023_12_04)
	# lxc-user-nic \| builtin \| Fast ✅ \| Fast ✅ \| ❌ \| ❌ \| Experimental
	# (bypass4netns) \| (bypass4netns) \| Fast ✅ \| Fast ✅ \| ✅ \| ✅ \| (Not integrated to RootlessKit)

	# See the documentation for the further information: https://docs.docker.com/go/rootless/

	set -e -x
	case "$1" in
	"check" \| "install" \| "uninstall")
	echo "Did you mean 'dockerd-rootless-setuptool.sh $@' ?"
	exit 1
	;;
	esac
	if ! [ -w "$XDG_RUNTIME_DIR" ]; then
	echo "XDG_RUNTIME_DIR needs to be set and writable"
	exit 1
	fi
	if ! [ -d "$HOME" ]; then
	echo "HOME needs to be set and exist."
	exit 1
	fi

	mount_directory() {
	if [ -z "$_DOCKERD_ROOTLESS_CHILD" ]; then
	echo "mount_directory should be called from the child context. Otherwise data loss is at risk" >&2
	exit 1
	fi

	DIRECTORY="$1"
	if [ ! -d "$DIRECTORY" ]; then
	return
	fi

	# Bind mount directory: this makes this directory visible to
	# Dockerd, even if it is originally a symlink, given Dockerd does
	# not always follow symlinks. Some directories might also be
	# "copied-up", meaning that they will also be writable on the child
	# namespace; this will be the case only if they are provided as
	# --copy-up to the rootlesskit.
	DIRECTORY_REALPATH=$(realpath "$DIRECTORY")
	MOUNT_OPTIONS="${2:---bind}"
	rm -rf "$DIRECTORY"
	mkdir -p "$DIRECTORY"
	mount $MOUNT_OPTIONS "$DIRECTORY_REALPATH" "$DIRECTORY"
	}

	rootlesskit=""
	for f in docker-rootlesskit rootlesskit; do
	if command -v $f > /dev/null 2>&1; then
	rootlesskit=$f
	break
	fi
	done
	if [ -z "$rootlesskit" ]; then
	echo "rootlesskit needs to be installed"
	exit 1
	fi

	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR:=$XDG_RUNTIME_DIR/dockerd-rootless}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_NET:=}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_MTU:=}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER:=}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX:=auto}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP:=auto}"
	: "${DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK:=}"
	net=$DOCKERD_ROOTLESS_ROOTLESSKIT_NET
	port_driver=$DOCKERD_ROOTLESS_ROOTLESSKIT_PORT_DRIVER
	mtu=$DOCKERD_ROOTLESS_ROOTLESSKIT_MTU
	if [ -z "$net" ]; then
	if command -v slirp4netns > /dev/null 2>&1; then
	# If --netns-type is present in --help, slirp4netns is >= v0.4.0.
	if slirp4netns --help \| grep -qw -- --netns-type; then
	net=slirp4netns
	else
	echo "slirp4netns found but seems older than v0.4.0. Checking for other network drivers."
	fi
	fi
	if [ -z "$net" ]; then
	if command -v pasta > /dev/null 2>&1; then
	net=pasta
	fi
	fi
	if [ -z "$net" ]; then
	if command -v vpnkit > /dev/null 2>&1; then
	net=vpnkit
	fi
	fi
	if [ -z "$net" ]; then
	echo "One of slirp4netns (>= v0.4.0), pasta (passt >= 2023_12_04), or vpnkit needs to be installed"
	fi
	fi
	if [ "$net" = host ]; then
	echo "Unsupported RootlessKit network driver: $net"
	exit 1
	fi
	if [ -z "$mtu" ]; then
	if [ "$net" = slirp4netns -o "$net" = pasta ]; then
	mtu=65520
	else
	mtu=1500
	fi
	fi
	if [ -z "$port_driver" ]; then
	if [ "$net" = pasta ]; then
	port_driver=implicit
	else
	port_driver=builtin
	fi
	fi

	host_loopback="--disable-host-loopback"
	if [ "$DOCKERD_ROOTLESS_ROOTLESSKIT_DISABLE_HOST_LOOPBACK" = "false" ]; then
	host_loopback=""
	fi

	dockerd="${DOCKERD:-dockerd}"

	if [ -z "$_DOCKERD_ROOTLESS_CHILD" ]; then
	_DOCKERD_ROOTLESS_CHILD=1
	export _DOCKERD_ROOTLESS_CHILD
	if [ "$(id -u)" = "0" ]; then
	echo "This script must be executed as a non-privileged user"
	exit 1
	fi
	# `selinuxenabled` always returns false in RootlessKit child, so we execute `selinuxenabled` in the parent.
	# https://github.com/rootless-containers/rootlesskit/issues/94
	if command -v selinuxenabled > /dev/null 2>&1 && selinuxenabled; then
	_DOCKERD_ROOTLESS_SELINUX=1
	export _DOCKERD_ROOTLESS_SELINUX
	fi
	# Re-exec the script via RootlessKit, so as to create unprivileged {user,mount,network} namespaces.
	#
	# --copy-up allows removing/creating files in the directories by creating tmpfs and symlinks
	# * /etc: copy-up is required so as to prevent `/etc/resolv.conf` in the
	# namespace from being unexpectedly unmounted when `/etc/resolv.conf` is recreated on the host
	# (by either systemd-networkd or NetworkManager)
	# * /run: copy-up is required so that we can create /run/docker (hardcoded for plugins) in our namespace
	exec $rootlesskit \
	--state-dir=$DOCKERD_ROOTLESS_ROOTLESSKIT_STATE_DIR \
	--net=$net --mtu=$mtu \
	--slirp4netns-sandbox=$DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SANDBOX \
	--slirp4netns-seccomp=$DOCKERD_ROOTLESS_ROOTLESSKIT_SLIRP4NETNS_SECCOMP \
	$host_loopback --port-driver=$port_driver \
	--copy-up=/etc --copy-up=/run \
	--propagation=rslave \
	$DOCKERD_ROOTLESS_ROOTLESSKIT_FLAGS \
	"$0" "$@"
	else
	[ "$_DOCKERD_ROOTLESS_CHILD" = 1 ]

	# The Container Device Interface (CDI) specs can be found by default
	# under {/etc,/var/run}/cdi. More information at:
	# https://github.com/cncf-tags/container-device-interface
	#
	# In order to use the Container Device Interface (CDI) integration,
	# the CDI paths need to exist before the Docker daemon is started in
	# order for it to read the CDI specification files. Otherwise, a
	# Docker daemon restart will be required for the daemon to discover
	# them.
	#
	# If another set of CDI paths (other than the default /etc/cdi and
	# /var/run/cdi) are configured through the Docker configuration file
	# (using "cdi-spec-dirs"), they need to be bind mounted in rootless
	# mode; otherwise the Docker daemon won't have access to the CDI
	# specification files.
	mount_directory /etc/cdi
	mount_directory /var/run/cdi

	# remove the symlinks for the existing files in the parent namespace if any,
	# so that we can create our own files in our mount namespace.
	rm -f /run/docker /run/containerd /run/xtables.lock

	if [ -n "$_DOCKERD_ROOTLESS_SELINUX" ]; then
	# iptables requires /run in the child to be relabeled. The actual /run in the parent is unaffected.
	# https://github.com/containers/podman/blob/e6fc34b71aa9d876b1218efe90e14f8b912b0603/libpod/networking_linux.go#L396-L401
	# https://github.com/moby/moby/issues/41230
	chcon system_u:object_r:iptables_var_run_t:s0 /run
	fi

	if [ "$(stat -c %T -f /etc)" = "tmpfs" ] && [ -L "/etc/ssl" ]; then
	# Workaround for "x509: certificate signed by unknown authority" on openSUSE Tumbleweed.
	# https://github.com/rootless-containers/rootlesskit/issues/225
	mount_directory /etc/ssl "--rbind"
	fi

	exec "$dockerd" "$@"
	fi