publish-ip script will work on systems without kiki

Instead of just looking for host keys where kiki leaves them, publish-ip will
(after not finding kiki keys) try to access the system keys, and even use the
user's keys.

Thus it is now appropriate to run stand-alone on any Debian machine.

1 files changed, 18 insertions, 3 deletions

diff --git a/src/publish-ip.sh b/src/publish-ip.sh
index 7da41b9..37fd2e3 100755
--- a/src/publish-ip.sh
+++ b/src/publish-ip.sh
@@ -1,5 +1,8 @@
 #!/bin/sh
 
+kiki_hostkey=/var/cache/kiki/config/ssh_host_rsa_key
+debian_hostkey=/etc/ssh/ssh_host_rsa_key
+
 determine_lan_ip()
 {
   ip -4 -oneline addr show |
@@ -8,8 +11,13 @@ determine_lan_ip()
         *'scope global'*) ;;
         *) continue ;;
       esac
-      case "$ip" in
-        192.168.10.1/24) continue ;;
+      # Exclude our IP address on br0 -- hosts connected via this device should
+      # be receiving DNS servers from us via DHCP, so dyndns is unnecessary.
+      # However, perhaps we could install a third entry in the dyndns. (Perhaps
+      # something like *.br0.ssh.cryptonomic.net would give us automatic names
+      # for all devices.)
+      case "$dev" in
+        br0) continue ;;
       esac
       echo ${ip%/*}
       break
@@ -35,4 +43,11 @@ else
   set --
 fi
 
-ssh -o GlobalKnownHostsFile="$tmpfile" -i /var/cache/kiki/config/ssh_host_rsa_key dyndns@ssh.cryptonomic.net "$@"
+hostkey=
+for f in "$kiki_hostkey" "$debian_hostkey"; do
+    [ -r "$f" ] || continue
+    hostkey=$f
+    break
+done
+
+ssh -o GlobalKnownHostsFile="$tmpfile" ${hostkey:+ -i "$hostkey"} dyndns@ssh.cryptonomic.net "$@"