commit bb9fb95ffc2dcd537ff0a948441700e8812af60b
author William A. Kennington III <wak@google.com> Mon Sep 27 18:10:27 2021 -0700
committer William A. Kennington III <wak@google.com> Tue Sep 28 22:50:10 2021 +0000
tree 0aea8ba9b2a2918cb5c0d1a29ba2b59bc9d69a67
parent c7454fb1c54ec6281a42b7cdb29e746b808eb271

meta-google: gbmc-ncsi-config: Parse hostnames from RA

We need the hostname to be properly configured in order to login with
GLOME. This derives the hostname from the FQDN that is passed via the
DNS list in the RA messages from the smart NIC.

Change-Id: I4e7a414b6b75bfb227df5763917e9e5d09579d7d
Signed-off-by: William A. Kennington III <wak@google.com>

meta-google/recipes-google/ncsi/files/gbmc-ncsi-ip-from-ra.sh.in

diff --git a/meta-google/recipes-google/ncsi/files/gbmc-ncsi-ip-from-ra.sh.in b/meta-google/recipes-google/ncsi/files/gbmc-ncsi-ip-from-ra.sh.in
index e4ee10d..7ba159f 100755
--- a/meta-google/recipes-google/ncsi/files/gbmc-ncsi-ip-from-ra.sh.in
+++ b/meta-google/recipes-google/ncsi/files/gbmc-ncsi-ip-from-ra.sh.in
@@ -25,15 +25,20 @@
   while read line; do
     if [ -z "$line" ]; then
       pfx=
+      host=
     elif [[ "$line" =~ ^Prefix' '*:' '*(.*)/([0-9]+)$ ]]; then
       t_pfx="${BASH_REMATCH[1]}"
       t_pfx_len="${BASH_REMATCH[2]}"
       ip_to_bytes t_pfx_b "$t_pfx" || continue
       (( t_pfx_len == 76 && t_pfx_b[8] & 0xfd == 0xfd )) || continue
       (( t_pfx_b[9] |= 1 ))
+      hextet="fd$(printf '%02x' ${t_pfx_b[9]})"
       pfx="$(ip_bytes_to_str t_pfx_b)"
       (( t_pfx_b[9] &= 0xf0 ))
       stateless_pfx="$(ip_bytes_to_str t_pfx_b)"
+    elif [[ "$line" =~ ^'DNS search list'' '*:' '*([^.-]*)[^.]*[.](.*.google.com)$ ]]; then
+      host="${BASH_REMATCH[1]}"
+      domain="${BASH_REMATCH[2]}"
     elif [[ "$line" =~ ^from' '(.*)$ ]]; then
       rtr="${BASH_REMATCH[1]}"
       (( "${#pfx}" != 0 )) || continue
@@ -102,6 +107,11 @@
       systemctl reset-failed nftables
       systemctl --no-block restart nftables
 
+      # Set the machine hostname if discovered
+      if [ -n "$host" ]; then
+        hostnamectl set-hostname "$host-n$hextet.$domain"
+      fi
+
       old_pfx="$pfx"
       old_rtr="$rtr"
     fi