xref: /src/etc/rc.d/network

#!/bin/sh
#
# $NetBSD: network,v 1.85 2020/10/16 15:31:04 kim Exp $
#

# PROVIDE: network
# REQUIRE: ipfilter ipsec CRITLOCALMOUNTED root tty sysctl
# BEFORE:  NETWORKING

$_rc_subr_loaded . /etc/rc.subr

name="network"
start_cmd="network_start"
stop_cmd="network_stop"

nl='
' # a newline

intmissing()
{
	local int="$1"
	shift
	for i; do
		if [ "$int" = "$i" ]; then
			return 1
		fi
	done
	return 0
}

have_inet6()
{
	/sbin/ifconfig lo0 inet6 >/dev/null 2>&1
}

network_start()
{
	# set hostname, turn on network
	#
	echo "Starting network."

	network_start_hostname
	network_start_domainname
	network_start_loopback
	have_inet6 &&
	network_start_ipv6_route
	[ "$net_interfaces" != NO ] &&
	network_start_interfaces
	network_start_aliases
	network_start_defaultroute
	network_start_defaultroute6
	have_inet6 &&
	network_wait_dad
	network_start_resolv
	network_start_local
}

network_start_hostname()
{
	# If $hostname is set, use it for my Internet name,
	# otherwise use /etc/myname
	#
	if [ -z "$hostname" ] && [ -f /etc/myname ]; then
		hostname=$(kat /etc/myname)
	fi
	if [ -n "$hostname" ]; then
		echo "Hostname: $hostname"
		hostname $hostname
	else
		# Don't warn about it if we're going to run
		# DHCP later, as we will probably get the
		# hostname at that time.
		#
		if ! checkyesno dhcpcd && \
			[ -z "$(hostname)" ]
		then
			warn "\$hostname not set."
		fi
	fi
}

network_start_domainname()
{
	# Check $domainname first, then /etc/defaultdomain,
	# for NIS/YP domain name
	#
	if [ -z "$domainname" ] && [ -f /etc/defaultdomain ]; then
		domainname=$(kat /etc/defaultdomain)
	fi
	if [ -n "$domainname" ]; then
		echo "NIS domainname: $domainname"
		domainname $domainname
	fi

	# Flush all routes just to make sure it is clean
	if checkyesno flushroutes; then
		/sbin/route -qn flush
	fi
}

network_start_loopback()
{
	# Set the address for the first loopback interface, so that the
	# auto-route from a newly configured interface's address to lo0
	# works correctly.
	#
	# NOTE: obscure networking problems will occur if lo0 isn't configured.
	#
	/sbin/ifconfig lo0 inet 127.0.0.1

	# According to RFC1122, 127.0.0.0/8 must not leave the node.
	#
	/sbin/route -q add -inet 127.0.0.0 -netmask 0xff000000 127.0.0.1 -reject
}

network_start_ipv6_route()
{
	# IPv6 routing setups, and host/router mode selection.
	#
	# We have IPv6 support in kernel.

	# disallow link-local unicast dest without outgoing scope
	# identifiers.
	#
	/sbin/route -q add -inet6 fe80:: -prefixlen 10 ::1 -reject

	# disallow the use of the RFC3849 documentation address
	#
	/sbin/route -q add -inet6 2001:db8:: -prefixlen 32 ::1 -reject

	# IPv6 site-local scoped address prefix (fec0::/10)
	# has been deprecated by RFC3879.
	#
	if [ -n "$ip6sitelocal" ]; then
		warn "\$ip6sitelocal is no longer valid"
	fi

	# disallow "internal" addresses to appear on the wire.
	#
	/sbin/route -q add -inet6 ::ffff:0.0.0.0 -prefixlen 96 ::1 -reject

	# disallow packets to malicious IPv4 compatible prefix
	#
	/sbin/route -q add -inet6 ::224.0.0.0 -prefixlen 100 ::1 -reject
	/sbin/route -q add -inet6 ::127.0.0.0 -prefixlen 104 ::1 -reject
	/sbin/route -q add -inet6 ::0.0.0.0 -prefixlen 104 ::1 -reject
	/sbin/route -q add -inet6 ::255.0.0.0 -prefixlen 104 ::1 -reject

	# disallow packets to malicious 6to4 prefix
	#
	/sbin/route -q add -inet6 2002:e000:: -prefixlen 20 ::1 -reject
	/sbin/route -q add -inet6 2002:7f00:: -prefixlen 24 ::1 -reject
	/sbin/route -q add -inet6 2002:0000:: -prefixlen 24 ::1 -reject
	/sbin/route -q add -inet6 2002:ff00:: -prefixlen 24 ::1 -reject

	# Completely disallow packets to IPv4 compatible prefix.
	# This may conflict with RFC1933 under following circumstances:
	# (1) An IPv6-only KAME node tries to originate packets to IPv4
	#     compatible destination.  The KAME node has no IPv4
	#     compatible support.  Under RFC1933, it should transmit
	#     native IPv6 packets toward IPv4 compatible destination,
	#     hoping it would reach a router that forwards the packet
	#     toward auto-tunnel interface.
	# (2) An IPv6-only node originates a packet to IPv4 compatible
	#     destination.  A KAME node is acting as an IPv6 router, and
	#     asked to forward it.
	# Due to rare use of IPv4 compatible address, and security
	# issues with it, we disable it by default.
	#
	/sbin/route -q add -inet6 ::0.0.0.0 -prefixlen 96 ::1 -reject

	/sbin/sysctl -qw net.inet6.ip6.forwarding=0

	case $ip6mode in
	router)
		echo 'IPv6 mode: router'
		/sbin/sysctl -qw net.inet6.ip6.forwarding=1

		# disallow unique-local unicast forwarding without
		# explicit configuration.
		if ! checkyesno ip6uniquelocal; then
			/sbin/route -q add -inet6 fc00:: -prefixlen 7 \
			    ::1 -reject
		fi
		;;

	autohost)
		if ! checkyesno dhcpcd; then
			warn "rtsol and kernel ra handling have been removed"
			warn "please configure dhcpcd in its place."
		fi
		;;

	host)
		echo 'IPv6 mode: host'
		;;

	*)	warn "invalid \$ip6mode value "\"$ip6mode\"
		;;

	esac
}

network_start_interfaces()
{
	# Configure all of the network interfaces listed in $net_interfaces;
	# if $auto_ifconfig is YES, grab all interfaces from ifconfig.
	# In the following, "xxN" stands in for interface names, like "le0".
	#
	# For any interfaces that has an $ifconfig_xxN variable
	# associated, we break it into lines using ';' as a separator,
	# then process it just like the contents of an /etc/ifconfig.xxN
	# file.
	#
	# For each line from the $ifconfig_xxN variable or the
	# /etc/ifconfig.xxN file, we ignore comments and blank lines,
	# treat lines beginning with "!" as commands to execute, treat
	# "dhcp" as a special case to invoke dhcpcd, treat "rtsol" as
	# a special case to send a router solicitation, and for any other
	# line we run "ifconfig xxN", using each line of the file as the
	# arguments for a separate "ifconfig" invocation.
	#
	# In order to configure an interface reasonably, you at the very least
	# need to specify "[addr_family] [hostname]" (e.g "inet my.domain.org"),
	# and probably a netmask (as in "netmask 0xffffffe0"). You will
	# frequently need to specify a media type, as in "media UTP", for
	# interface cards with multiple media connections that do not
	# autoconfigure. See the ifconfig manual page for details.
	#
	# Note that /etc/ifconfig.xxN takes multiple lines.  The following
	# configuration is possible:
	#	inet 10.1.1.1 netmask 0xffffff00
	#	inet 10.1.1.2 netmask 0xffffff00 alias
	#	inet6 2001:db8::1 prefixlen 64 alias
	#
	# You can put shell script fragment into /etc/ifconfig.xxN by
	# starting a line with "!".  Refer to ifconfig.if(5) for details.
	#
	ifaces="$(/sbin/ifconfig -l)"
	if checkyesno auto_ifconfig; then
		tmp="$ifaces"
		for cloner in $(/sbin/ifconfig -C); do
			for int in /etc/ifconfig.${cloner}[0-9]*; do
				[ ! -f $int ] && break
				tmp="$tmp ${int##*.}"
			done
		done
	else
		tmp="$net_interfaces"
	fi
	echo -n 'Configuring network interfaces:'
	for int in $tmp; do
		eval argslist=\$ifconfig_$int

		# Skip interfaces that do not have explicit
		# configuration information.  If auto_ifconfig is
		# false then also warn about such interfaces.
		#
		if [ -z "$argslist" ] && ! [ -f /etc/ifconfig.$int ]
		then
			if ! checkyesno auto_ifconfig; then
				echo
				warn \
		"/etc/ifconfig.$int missing and ifconfig_$int not set;"
				warn "interface $int not configured."
			fi
			continue
		fi

		echo -n " $int"

		# Create the interface if necessary.
		# If the interface did not exist before,
		# then also resync ipf(4).
		#
		if intmissing $int $ifaces; then
			if /sbin/ifconfig $int create && \
			   checkyesno ipfilter; then
				/sbin/ipf -y >/dev/null
			fi
		fi

		# If $ifconfig_xxN is empty, then use
		# /etc/ifconfig.xxN, which we know exists due to
		# an earlier test.
		#
		# If $ifconfig_xxN is non-empty and contains a
		# newline, then just use it as is.  (This allows
		# semicolons through unmolested.)
		#
		# If $ifconfig_xxN is non-empty and does not
		# contain a newline, then convert all semicolons
		# to newlines.
		#
		case "$argslist" in
		'')
			cat /etc/ifconfig.$int
			;;
		*"${nl}"*)
			echo "$argslist"
			;;
		*)
			(
				set -o noglob
				IFS=';'; set -- $argslist
				#echo >&2 "[$#] [$1] [$2] [$3] [$4]"
				IFS="$nl"; echo "$*"
			)
			;;
		esac |
		collapse_backslash_newline |
		while read -r args; do
			case "$args" in
			''|"#"*|create)
				;;
			"!"*)
				# Run arbitrary command in a subshell.
				( eval "${args#*!}" )
				;;
			dhcp)
				if ! checkyesno dhcpcd; then
					/sbin/dhcpcd -n --dhcp \
						${dhcpcd_flags} $int
				fi
				;;
			rtsol)
				if ! checkyesno dhcpcd; then
					/sbin/dhcpcd -n6b \
						${dhcpcd_flags} $int
				fi
				;;
			*)
				# Pass args to ifconfig.  Note
				# that args may contain embedded
				# shell metacharacters, such as
				# "ssid 'foo;*>bar'". We eval
				# one more time so that things
				# like ssid "Columbia University" work.
				(
					set -o noglob
					eval set -- $args
					#echo >&2 "[$#] [$1] [$2] [$3]"
					/sbin/ifconfig $int "$@"
				)
				;;
			esac
		done
		configured_interfaces="$configured_interfaces $int"
	done
	echo "."
}

network_start_aliases()
{
	echo -n "Adding interface aliases:"

	# Check if each configured interface xxN has an $ifaliases_xxN variable
	# associated, then configure additional IP addresses for that interface.
	# The variable contains a list of "address netmask" pairs, with
	# "netmask" set to "-" if the interface default netmask is to be used.
	#
	# Note that $ifaliases_xxN works only in certain cases and its
	# use is not recommended.  Use /etc/ifconfig.xxN or multiple
	# commands in $ifconfig_xxN instead.
	#
	for int in lo0 $configured_interfaces; do
		eval args=\$ifaliases_$int
		if [ -n "$args" ]; then
			set -- $args
			while [ $# -ge 2 ]; do
				addr=$1 ; net=$2 ; shift 2
				if [ "$net" = "-" ]; then
					# for compatibility only, obsolete
					/sbin/ifconfig $int inet alias $addr
				else
					/sbin/ifconfig $int inet alias $addr \
					    netmask $net
				fi
				echo -n " $int:$addr"
			done
		fi
	done

	# /etc/ifaliases, if it exists, contains the names of additional IP
	# addresses for each interface. It is formatted as a series of lines
	# that contain
	#	address interface netmask
	#
	# Note that /etc/ifaliases works only in certain cases and its
	# use is not recommended.  Use /etc/ifconfig.xxN or multiple
	# commands in $ifconfig_xxN instead.
	#
	if [ -f /etc/ifaliases ]; then
		while read addr int net; do
			if [ -z "$net" ]; then
				# for compatibility only, obsolete
				/sbin/ifconfig $int inet alias $addr
			else
				/sbin/ifconfig $int inet alias $addr netmask $net
			fi
		done < /etc/ifaliases
	fi

	echo "." # for "Adding interface aliases:"
}

network_start_defaultroute()
{
	# Check $defaultroute, then /etc/mygate, for the name or address
	# of my IPv4 gateway host. If using a name, that name must be in
	# /etc/hosts.
	#
	if [ -z "$defaultroute" ] && [ -f /etc/mygate ]; then
		defaultroute=$(kat /etc/mygate)
	fi
	if [ -n "$defaultroute" ]; then
		/sbin/route add default $defaultroute
	fi
}

network_start_defaultroute6()
{
	# Check $defaultroute6, then /etc/mygate6, for the name or address
	# of my IPv6 gateway host. If using a name, that name must be in
	# /etc/hosts.  Note that the gateway host address must be a link-local
	# address if it is not using an stf* interface.
	#
	if [ -z "$defaultroute6" ] && [ -f /etc/mygate6 ]; then
		defaultroute6=$(kat /etc/mygate6)
	fi
	if [ -n "$defaultroute6" ]; then
		if [ "$ip6mode" = "autohost" ]; then
			echo
			warn \
	    "ip6mode is set to 'autohost' and a v6 default route is also set."
		fi
		/sbin/route add -inet6 default $defaultroute6
	fi
}

network_wait_dad()
{
	# Wait for the DAD flags to clear from all addresses.
	if [ -n "$ifconfig_wait_dad_flags" ]; then
		echo "Waiting for duplicate address detection to finish..."
		ifconfig $ifconfig_wait_dad_flags
	fi
}

network_start_resolv()
{
	resconf=

	if [ -n "$dns_domain" ]; then
		resconf="${resconf}domain $dns_domain$nl"
	fi
	if [ -n "$dns_search" ]; then
		resconf="${resconf}search $dns_search$nl"
	fi
	for n in $dns_nameservers; do
		resconf="${resconf}nameserver $n$nl"
	done
	if [ -n "$dns_sortlist" ]; then
		resconf="${resconf}sortlist $dns_sortlist$nl"
	fi
	if [ -n "$dns_options" ]; then
		resconf="${resconf}options $dns_options$nl"
	fi
	if [ -n "$resconf" ]; then
		resconf="# Generated by /etc/rc.d/network$nl$resconf"
		echo 'Configuring resolv.conf'
		printf %s "$resconf" | resolvconf -m "${dns_metric:-0}" -a network
	fi
}

network_start_local()
{
	# XXX this must die
	if [ -s /etc/netstart.local ]; then
		sh /etc/netstart.local start
	fi
}

network_stop()
{
	echo "Stopping network."

	network_stop_local
	network_stop_resolv
	network_stop_aliases
	[ "$net_interfaces" != NO ] &&
	network_stop_interfaces
	network_stop_route
}

network_stop_local()
{
	# XXX this must die
	if [ -s /etc/netstart.local ]; then
		sh /etc/netstart.local stop
	fi
}

network_stop_resolv()
{
	resolvconf -f -d network
}

network_stop_aliases()
{
	echo "Deleting aliases."
	if [ -f /etc/ifaliases ]; then
		while read addr int net; do
			/sbin/ifconfig $int inet delete $addr
		done < /etc/ifaliases
	fi

	for int in $(/sbin/ifconfig -lu); do
		eval args=\$ifaliases_$int
		if [ -n "$args" ]; then
			set -- $args
			while [ $# -ge 2 ]; do
				addr=$1 ; net=$2 ; shift 2
				/sbin/ifconfig $int inet delete $addr
			done
		fi
	done
}

network_stop_interfaces()
{
	# down interfaces
	#
	echo -n 'Downing network interfaces:'
	if checkyesno auto_ifconfig; then
		tmp=$(/sbin/ifconfig -l)
	else
		tmp="$net_interfaces"
	fi
	for int in $tmp; do
		eval args=\$ifconfig_$int
		if [ -n "$args" ] || [ -f /etc/ifconfig.$int ]; then
			echo -n " $int"
			if [ -f /var/run/dhcpcd-$int.pid ]; then
				/sbin/dhcpcd -k $int 2> /dev/null
			fi
			/sbin/ifconfig $int down
			if /sbin/ifconfig $int destroy 2>/dev/null && \
			   checkyesno ipfilter; then
				# resync ipf(4)
				/sbin/ipf -y >/dev/null
			fi
		fi
	done
	echo "."
}

network_stop_route()
{
	# flush routes
	#
	if checkyesno flushroutes; then
		/sbin/route -qn flush
	fi
}

load_rc_config $name
load_rc_config_var dhcpcd dhcpcd
load_rc_config_var ipfilter ipfilter
run_rc_command "$1"