feat(nbd): support ipv6 link local nbds

dracut.cmdline.7.asc

@@ -575,7 +575,7 @@ USB Android phone::
 * enp0s29u1u2
 =====================
 
-**ip=**__{dhcp|on|any|dhcp6|auto6|either6|single-dhcp}__::
+**ip=**__{dhcp|on|any|dhcp6|auto6|either6|link6|single-dhcp}__::
     dhcp|on|any::: get ip from dhcp server from all interfaces. If root=dhcp,
     loop sequentially through all interfaces (eth0, eth1, ...) and use the first
     with a valid DHCP root-path.
@@ -592,12 +592,15 @@ USB Android phone::
 
     either6::: if auto6 fails, then dhcp6
 
-**ip=**__<interface>__:__{dhcp|on|any|dhcp6|auto6}__[:[__<mtu>__][:__<macaddr>__]]::
+    link6::: bring up interface for IPv6 link-local addressing
+
+**ip=**__<interface>__:__{dhcp|on|any|dhcp6|auto6|link6}__[:[__<mtu>__][:__<macaddr>__]]::
     This parameter can be specified multiple times.
 +
 =====================
 dhcp|on|any|dhcp6::: get ip from dhcp server on a specific interface
 auto6::: do IPv6 autoconfiguration
+link6::: bring up interface for IPv6 link local address
 <macaddr>::: optionally **set** <macaddr> on the <interface>. This
 cannot be used in conjunction with the **ifname** argument for the
 same <interface>.

modules.d/35network-legacy/ifup.sh

@@ -123,6 +123,19 @@ do_ipv6auto() {
     return $ret
 }
 
+do_ipv6link() {
+    local ret
+    load_ipv6
+    echo 0 > /proc/sys/net/ipv6/conf/$netif/forwarding
+    echo 0 > /proc/sys/net/ipv6/conf/$netif/accept_ra
+    echo 0 > /proc/sys/net/ipv6/conf/$netif/accept_redirects
+    linkup $netif
+
+    [ -n "$hostname" ] && echo "echo $hostname > /proc/sys/kernel/hostname" > /tmp/net.$netif.hostname
+
+    return $ret
+}
+
 # Handle static ip configuration
 do_static() {
     strglobin $ip '*:*:*' && load_ipv6
@@ -449,6 +462,8 @@ for p in $(getargs ip=); do
                 do_ipv6auto ;;
             either6)
                 do_ipv6auto || do_dhcp -6 ;;
+            link6)
+                do_ipv6link ;;
             *)
                 do_static ;;
         esac

modules.d/35network-legacy/parse-ip-opts.sh

@@ -75,7 +75,7 @@ for p in $(getargs ip=); do
                 [ -z "$mask" ] && \
                     die "Sorry, automatic calculation of netmask is not yet supported"
                 ;;
-            auto6);;
+            auto6|link6);;
             either6);;
             dhcp|dhcp6|on|any|single-dhcp) \
                 [ -n "$NEEDBOOTDEV" ] && [ -z "$dev" ] && \

modules.d/95nbd/nbd-generator.sh

@@ -14,7 +14,13 @@ GENERATOR_DIR="$2"
 ROOTFLAGS="$(getarg rootflags)"
 
 nroot=${root#nbd:}
-nbdserver=${nroot%%:*}; nroot=${nroot#*:}
+nbdserver=${nroot%%:*};
+if [ "${nbdserver%"${nbdserver#?}"}" = "[" ]; then
+    nbdserver=${nroot#[}
+    nbdserver=${nbdserver%%]:*}\]; nroot=${nroot#*]:}
+else
+    nroot=${nroot#*:}
+fi
 nbdport=${nroot%%:*}; nroot=${nroot#*:}
 nbdfstype=${nroot%%:*}; nroot=${nroot#*:}
 nbdflags=${nroot%%:*}

modules.d/95nbd/nbdroot.sh

@@ -22,7 +22,13 @@ NEWROOT="$3"
 [ "${nroot%%:*}" = "nbd" ] || return
 
 nroot=${nroot#nbd:}
-nbdserver=${nroot%%:*}; nroot=${nroot#*:}
+nbdserver=${nroot%%:*};
+if [ "${nbdserver%"${nbdserver#?}"}" = "[" ]; then
+    nbdserver=${nroot#[}
+    nbdserver=${nbdserver%%]:*}; nroot=${nroot#*]:}
+else
+    nroot=${nroot#*:}
+fi
 nbdport=${nroot%%:*}; nroot=${nroot#*:}
 nbdfstype=${nroot%%:*}; nroot=${nroot#*:}
 nbdflags=${nroot%%:*}
@@ -91,29 +97,37 @@ done
 # If we didn't get a root= on the command line, then we need to
 # add the udev rules for mounting the nbd0 device
 if [ "$root" = "block:/dev/root" -o "$root" = "dhcp" ]; then
-    printf 'KERNEL=="nbd0", ENV{DEVTYPE}!="partition", ENV{ID_FS_TYPE}=="?*", SYMLINK+="root"\n' >> /etc/udev/rules.d/99-nbd-root.rules
+    printf 'KERNEL=="nbd0", ENV{DEVTYPE}!="partition", ENV{ID_FS_TYPE}=="?*", SYMLINK+="root"\n' > /etc/udev/rules.d/99-nbd-root.rules
     udevadm control --reload
-    type write_fs_tab >/dev/null 2>&1 || . /lib/fs-lib.sh
-    write_fs_tab /dev/root "$nbdfstype" "$fsopts"
     wait_for_dev -n /dev/root
 
     if [ -z "$DRACUT_SYSTEMD" ]; then
+        type write_fs_tab >/dev/null 2>&1 || . /lib/fs-lib.sh
+
+        write_fs_tab /dev/root "$nbdfstype" "$fsopts"
+
         printf '/bin/mount %s\n' \
              "$NEWROOT" \
              > $hookdir/mount/01-$$-nbd.sh
     fi
+    # if we're on systemd, use the nbd-generator script
+    # to create the /sysroot mount.
 fi
 
+# supported since nbd 3.8 via 77e97612
 if strstr "$(nbd-client --help 2>&1)" "systemd-mark"; then
-    preopts="--systemd-mark $preopts"
+    preopts="-systemd-mark $preopts"
 fi
 
 if [ "$nbdport" -gt 0 ] 2>/dev/null; then
-    nbd-client "$nbdserver" $nbdport /dev/nbd0 $preopts $opts || exit 1
+    nbdport="$nbdport"
 else
-    nbd-client -name "$nbdport" "$nbdserver" /dev/nbd0 $preopts $opts || exit 1
+    nbdport="-name $nbdport"
 fi
 
+nbd-client -check /dev/nbd0 >/dev/null || \
+    nbd-client "$nbdserver" $nbdport /dev/nbd0 $preopts $opts || exit 1
+
 # NBD doesn't emit uevents when it gets connected, so kick it
 echo change > /sys/block/nbd0/uevent
 udevadm settle

modules.d/95nbd/parse-nbdroot.sh

@@ -9,18 +9,6 @@
 # root= takes precedence over netroot= if root=nbd[...]
 #
 
-# Sadly there's no easy way to split ':' separated lines into variables
-netroot_to_var() {
-    local v=${1}:
-    set --
-    while [ -n "$v" ]; do
-        set -- "$@" "${v%%:*}"
-        v=${v#*:}
-    done
-
-    unset server port
-    server=$2; port=$3;
-}
 
 # This script is sourced, so root should be set. But let's be paranoid
 [ -z "$root" ] && root=$(getarg root=)
@@ -46,13 +34,18 @@ fi
 [ "${netroot%%:*}" = "nbd" ] || return
 
 
-#if [ -n "${DRACUT_SYSTEMD}" ] && [ "$root" = "dhcp" ]; then
-#    echo "root=$netroot" > /etc/cmdline.d/root.conf
-#    systemctl --no-block daemon-reload
-#fi
-
 # Check required arguments
-netroot_to_var $netroot
+nroot=${netroot#nbd:}
+server=${nroot%%:*};
+if [ "${server%"${server#?}"}" = "[" ]; then
+    server=${nroot#[}
+    server=${server%%]:*}\]; nroot=${nroot#*]:}
+else
+    nroot=${nroot#*:}
+fi
+port=${nroot%%:*}
+unset nroot
+
 [ -z "$server" ] && die "Argument server for nbdroot is missing"
 [ -z "$port" ] && die "Argument port for nbdroot is missing"
 
@@ -65,6 +58,6 @@ rootok=1
 # Shut up init error check
 if [ -z "$root" ]; then
     root=block:/dev/root
-    wait_for_dev -n /dev/root
+    # the device is created and waited for in ./nbdroot.sh
 fi
 

modules.d/99fs-lib/fs-lib.sh

@@ -247,7 +247,11 @@ write_fs_tab() {
         fi
     fi
 
-    echo "$_root /sysroot $_rootfstype $_rootflags $_fspassno 0" >> /etc/fstab
+    if grep -q "$_root /sysroot" /etc/fstab; then
+        echo "$_root /sysroot $_rootfstype $_rootflags $_fspassno 0" >> /etc/fstab
+    else
+        return
+    fi
 
     if type systemctl >/dev/null 2>/dev/null; then
         systemctl daemon-reload