dracut/0087.patch
Harald Hoyer 460d2c99f9 dracut-050-157.git20201002
git snapshot
2020-10-02 14:08:26 +02:00

141 lines
4.4 KiB
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From ceca74ccc397795db68ca6ffbe49d65af2178a50 Mon Sep 17 00:00:00 2001
From: Martin Wilck <mwilck@suse.de>
Date: Sat, 11 Jul 2020 00:15:34 +0200
Subject: [PATCH] dracut-functions: add ip_params_for_remote_addr() helper
This helper function takes a remote IP address, and tries to
determine the dracut command line arguments ip= and ifname= that
will make this remote address reachable during boot.
Functionality was taken from the module-setup.sh scripts of 95iscsi and 95nfs,
cleaned up and fixed some issues in particular with statically configured
networks, where the old code would print the unsupported string
"$ifname:static".
---
dracut-functions.sh | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 114 insertions(+)
diff --git a/dracut-functions.sh b/dracut-functions.sh
index b5c28248..07ae88c0 100755
--- a/dracut-functions.sh
+++ b/dracut-functions.sh
@@ -728,3 +728,117 @@ btrfs_devs() {
printf -- "%s\n" "$_dev"
done
}
+
+iface_for_remote_addr() {
+ set -- $(ip -o route get to "$1")
+ echo $3
+}
+
+local_addr_for_remote_addr() {
+ set -- $(ip -o route get to "$1")
+ echo $5
+}
+
+peer_for_addr() {
+ local addr=$1
+ local qtd
+
+ # quote periods in IPv4 address
+ qtd=${addr//./\\.}
+ ip -o addr show | \
+ sed -n 's%^.* '"$qtd"' peer \([0-9a-f.:]\{1,\}\(/[0-9]*\)\?\).*$%\1%p'
+}
+
+netmask_for_addr() {
+ local addr=$1
+ local qtd
+
+ # quote periods in IPv4 address
+ qtd=${addr//./\\.}
+ ip -o addr show | sed -n 's,^.* '"$qtd"'/\([0-9]*\) .*$,\1,p'
+}
+
+gateway_for_iface() {
+ local ifname=$1 addr=$2
+
+ case $addr in
+ *.*) proto=4;;
+ *:*) proto=6;;
+ *) return;;
+ esac
+ ip -o -$proto route show | \
+ sed -n "s/^default via \([0-9a-z.:]\{1,\}\) dev $ifname .*\$/\1/p"
+}
+
+# This works only for ifcfg-style network configuration!
+bootproto_for_iface() {
+ local ifname=$1
+ local dir
+
+ # follow ifcfg settings for boot protocol
+ for dir in network-scripts network; do
+ [ -f "/etc/sysconfig/$dir/ifcfg-$ifname" ] && {
+ sed -n "s/BOOTPROTO=[\"']\?\([[:alnum:]]\{1,\}\)[\"']\?.*\$/\1/p" \
+ "/etc/sysconfig/$dir/ifcfg-$ifname"
+ return
+ }
+ done
+}
+
+is_unbracketed_ipv6_address() {
+ strglob "$1" '*:*' && ! strglob "$1" '\[*:*\]'
+}
+
+# Create an ip= string to set up networking such that the given
+# remote address can be reached
+ip_params_for_remote_addr() {
+ local remote_addr=$1
+ local ifname local_addr peer netmask= gateway ifmac
+
+ [[ $remote_addr ]] || return 1
+ ifname=$(iface_for_remote_addr "$remote_addr")
+ [[ $ifname ]] || {
+ berror "failed to determine interface to connect to $remote_addr"
+ return 1
+ }
+
+ # ifname clause to bind the interface name to a MAC address
+ if [ -d "/sys/class/net/$ifname/bonding" ]; then
+ dinfo "Found bonded interface '${ifname}'. Make sure to provide an appropriate 'bond=' cmdline."
+ elif [ -e "/sys/class/net/$ifname/address" ] ; then
+ ifmac=$(cat "/sys/class/net/$ifname/address")
+ [[ $ifmac ]] && printf 'ifname=%s:%s ' "${ifname}" "${ifmac}"
+ fi
+
+ bootproto=$(bootproto_for_iface "$ifname")
+ case $bootproto in
+ dhcp|dhcp6|auto6) ;;
+ dhcp4)
+ bootproto=dhcp;;
+ static*|"")
+ bootproto=;;
+ *)
+ derror "bootproto \"$bootproto\" is unsupported by dracut, trying static configuration"
+ bootproto=;;
+ esac
+ if [[ $bootproto ]]; then
+ printf 'ip=%s:%s ' "${ifname}" "${bootproto}"
+ else
+ local_addr=$(local_addr_for_remote_addr "$remote_addr")
+ [[ $local_addr ]] || {
+ berror "failed to determine local address to connect to $remote_addr"
+ return 1
+ }
+ peer=$(peer_for_addr "$local_addr")
+ # Set peer or netmask, but not both
+ [[ $peer ]] || netmask=$(netmask_for_addr "$local_addr")
+ gateway=$(gateway_for_iface "$ifname" "$local_addr")
+ # Quote IPv6 addresses with brackets
+ is_unbracketed_ipv6_address "$local_addr" && local_addr="[$local_addr]"
+ is_unbracketed_ipv6_address "$peer" && peer="[$peer]"
+ is_unbracketed_ipv6_address "$gateway" && gateway="[$gateway]"
+ printf 'ip=%s:%s:%s:%s::%s:none ' \
+ "${local_addr}" "${peer}" "${gateway}" "${netmask}" "${ifname}"
+ fi
+
+}