From 68bbdccadf63733c968fa6256aea910b6a3dfdb4 Mon Sep 17 00:00:00 2001
From: David Kebler <dgkebler@gmail.com>
Date: Wed, 21 Aug 2024 18:48:51 -0700
Subject: [PATCH] change getip to not use dig but host use same code in
 sshd_dns and abort if no ip found

---
 modules/net-utils.mod | 11 ++++++++---
 modules/sshd-dns.mod  | 25 +++++++++++++++++++++++--
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/modules/net-utils.mod b/modules/net-utils.mod
index 4077a97..88ca4bb 100644
--- a/modules/net-utils.mod
+++ b/modules/net-utils.mod
@@ -37,8 +37,8 @@ lookup_host () {
 # usage:  lookup_host hostname < configfile >    
 local config; local host; local lhost
 config=$([[ $2 ]] && echo $2 || echo ${SSH_CONFIG:-$HOME/.ssh/config})
-host=$(get_hostname_host $1)return
-lhost=$(ssh -F $config -G $host | grep -w hostname | cut -d' ' -f2)
+host=$(get_hostname_host $1)
+lhost=$($(which ssh) -F $config -G $host | grep -w hostname | cut -d' ' -f2)
 [[ $lhost ]] && echo $lhost || echo $host
 }
 
@@ -107,6 +107,11 @@ dig +short myip.opendns.com @resolver1.opendns.com
 }
 
 getip () {
-dig +short $1 | tail -1
+[[ ! $1 ]] && return 1
+if ip=$(host -4 -t A $1); then 
+echo $ip | awk '{print $NF}'
+else 
+return 2
+fi
 }
 
diff --git a/modules/sshd-dns.mod b/modules/sshd-dns.mod
index 3de79e1..d926552 100644
--- a/modules/sshd-dns.mod
+++ b/modules/sshd-dns.mod
@@ -1,9 +1,21 @@
 #!/bin/bash
 
 sshd_dns () {
+
+local ip
 local dir	
 local dnsconf
 local conf
+
+_getip () {
+[[ ! $1 ]] && return 1
+if ip=$(host -4 -t A $1); then 
+echo $ip | awk '{print $NF}'
+else 
+return 2
+fi
+}
+
 dir=${1:-"/etc/ssh/sshd_config.d"}
 pushd "$dir" 1>/dev/null || return;
 for dnsconf in *.conf.dns; do
@@ -14,8 +26,17 @@ for dnsconf in *.conf.dns; do
     cat $conf
     echo -e "\n------------"
 	for host in $(sed -e 's/[ ,]/\n/g' $conf | sed -n 's/[Dd][Nn][Ss]://p'); do
-	echo found host $host, substituting $(dig +short $host) 
-	sudo sed -i 's/[Dd][Nn][Ss]:'$host'/'$(dig +short $host)'/g' $conf
+  echo host to lookup $host, 
+  if ip=$(_getip $host); then
+  echo  substituting $(dig +short $host) 
+	sudo sed -i 's/[Dd][Nn][Ss]:'$host'/'$ip'/g' $conf
+  else 
+  echo unable to find ip address for $host
+  echo fatal: removing $conf, exiting, 
+  sudo rm -f $conf
+  popd 1>/dev/null || return 2
+  return 2
+  fi
 	done
     echo "----- created sshd conf file $conf ----"
     cat $conf