#!/usr/bin/env bash

## 

usage() {
	echo 'Looks up ip via ldap and creates a krbconfig based on DC domain'
	echo 'USAGE: $0 <IP> '
	exit 1
}

[[ -z $1 ]] && usage


ip="$1"
if [[ "$ip" == *::* ]]; then
	ldap_host="ldap://[$ip]"
else
	ldap_host="ldap://$ip"
fi
echo "$ldap_host"

domain=$(ldapsearch -x -H $ldap_host -s base namingcontexts -b "" | awk -F'[=,]' \
	'tolower($0) ~ /namingcontexts:/ {print $2"."$4;exit}')

[[ $? -ne 0 ]] && echo 'ldapsearch failed' && exit 1

realm=${domain^^}
outfile="$domain.krb.conf"

cat << EOF > $outfile
[libdefaults]
	dns_default_realm = $realm
	dns_lookup_realm = true
	dns_lookupkdc = true
[realms]
	 $realm = {
		kdc = $ip:88
		admin_server = $ip:749
		default_domain = $domain
	}
[domain_realm]
	$domain =  $realm
	.$domain =  $realm

EOF

# cat << EOF | sed \
# -e "s/{{REALM_PLACEHOLDER}}/$realm/g" \
# -e "s/{{domain_placeholder}}/$domain/g" \
# -e "s/{{ip_placeholder}}/$ip/g" > "$outfile"
# [libdefaults]
#     default_realm = {{REALM_PLACEHOLDER}}
#     dns_lookup_realm = true
#     dns_lookup_kdc = true
#
# [realms]
#     {{REALM_PLACEHOLDER}} = {
#         kdc = {{ip_placeholder}}:88
#         admin_server = {{ip_placeholder}}:749
#         default_domain = {{domain_placeholder}}
#     }
#
# [domain_realm]
#     {{domain_placeholder}} = {{REALM_PLACEHOLDER}}
#     .{{domain_placeholder}} = {{REALM_PLACEHOLDER}}
# EOF

echo "[+] Domain: $domain @ $ip"
echo '[+] Created custom_krb5.conf'
echo '' 
echo 'To use: '
echo "export KRB5_CONFIG=\$PWD/$outfile"
echo ''