From 1dbeeaa46cdaff34241c0e7fb51c93d562036e01 Mon Sep 17 00:00:00 2001
From: Ptomerty <Ptomerty@users.noreply.github.com>
Date: Sun, 25 Nov 2018 21:29:18 -0500
Subject: [PATCH 1/3] resolve domains in ss-nat

---
 src/ss-nat | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/ss-nat b/src/ss-nat
index 1dfcc77b..9374b76f 100755
--- a/src/ss-nat
+++ b/src/ss-nat
@@ -21,9 +21,9 @@ usage() {
 
     Valid options are:
 
-        -s <server_ip>          ip address of shadowsocks remote server
+        -s <server_ip>          Host name or IP address of shadowsocks remote server
         -l <local_port>         port number of shadowsocks local server
-        -S <server_ip>          ip address of shadowsocks remote UDP server
+        -S <server_ip>          Host name or IP address of shadowsocks remote UDP server
         -L <local_port>         port number of shadowsocks local UDP server
         -i <ip_list_file>       a file content is bypassed ip list
         -I <interface>          lan interface of nat, default: eth0
@@ -170,13 +170,13 @@ EOF
 while getopts ":s:l:S:L:i:I:e:a:b:w:ouUfh" arg; do
 	case "$arg" in
 		s)
-			server=$OPTARG
+			server=$(dig +short $OPTARG)
 			;;
 		l)
 			local_port=$OPTARG
 			;;
 		S)
-			SERVER=$OPTARG
+			SERVER=$(dig +short $OPTARG)
 			;;
 		L)
 			LOCAL_PORT=$OPTARG

From f9cc909efa94310864b9c9bae3200aaf7c0c254a Mon Sep 17 00:00:00 2001
From: Ptomerty <Ptomerty@users.noreply.github.com>
Date: Thu, 29 Nov 2018 21:33:17 -0500
Subject: [PATCH 2/3] check if dig exists first

---
 src/ss-nat | 25 +++++++++++++++++++++----
 1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/ss-nat b/src/ss-nat
index 9374b76f..10b06fa8 100755
--- a/src/ss-nat
+++ b/src/ss-nat
@@ -10,6 +10,7 @@
 TAG="SS_SPEC"          # iptables tag
 IPT="iptables -t nat"  # alias of iptables
 FWI=$(uci get firewall.shadowsocks.path 2>/dev/null)  # firewall include file
+REGEX="[^0-9.]"		   # used to check if hostnames have letters
 
 usage() {
 	cat <<-EOF
@@ -21,9 +22,9 @@ usage() {
 
     Valid options are:
 
-        -s <server_ip>          Host name or IP address of shadowsocks remote server
+        -s <server_ip>          hostname (requires dig) or ip address of shadowsocks remote server
         -l <local_port>         port number of shadowsocks local server
-        -S <server_ip>          Host name or IP address of shadowsocks remote UDP server
+        -S <server_ip>          hostname (requires dig) or ip address of shadowsocks remote UDP server
         -L <local_port>         port number of shadowsocks local UDP server
         -i <ip_list_file>       a file content is bypassed ip list
         -I <interface>          lan interface of nat, default: eth0
@@ -170,13 +171,29 @@ EOF
 while getopts ":s:l:S:L:i:I:e:a:b:w:ouUfh" arg; do
 	case "$arg" in
 		s)
-			server=$(dig +short $OPTARG)
+			command -v dig > /dev/null &&
+				server=$(dig +short $OPTARG) ||
+				if [[ $OPTARG =~ $REGEX ]]
+				then
+					loger 3 "Hostname detected for server but no dig present to resolve!"
+					exit 1
+				else
+					server=$OPTARG
+				fi
 			;;
 		l)
 			local_port=$OPTARG
 			;;
 		S)
-			SERVER=$(dig +short $OPTARG)
+			command -v dig > /dev/null &&
+				SERVER=$(dig +short $OPTARG) ||
+				if [[ $OPTARG =~ $REGEX ]]
+				then
+					loger 3 "Hostname detected for UDP server but no dig present to resolve!"
+					exit 1
+				else
+					SERVER=$OPTARG
+				fi
 			;;
 		L)
 			LOCAL_PORT=$OPTARG

From d05970fd0c3647128fdc6146deecf91e7ffc2eb1 Mon Sep 17 00:00:00 2001
From: Ptomerty <Ptomerty@users.noreply.github.com>
Date: Thu, 29 Nov 2018 23:13:06 -0500
Subject: [PATCH 3/3] Use existing IP regex

---
 src/ss-nat | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/ss-nat b/src/ss-nat
index 10b06fa8..f4b1ebdb 100755
--- a/src/ss-nat
+++ b/src/ss-nat
@@ -10,7 +10,7 @@
 TAG="SS_SPEC"          # iptables tag
 IPT="iptables -t nat"  # alias of iptables
 FWI=$(uci get firewall.shadowsocks.path 2>/dev/null)  # firewall include file
-REGEX="[^0-9.]"		   # used to check if hostnames have letters
+IP_REGEX="^([0-9]{1,3}\.){3}[0-9]{1,3}"		      # used to check if input is a valid IP
 
 usage() {
 	cat <<-EOF
@@ -127,7 +127,7 @@ tp_rule() {
 }
 
 get_wan_ip() {
-	cat <<-EOF | grep -E "^([0-9]{1,3}\.){3}[0-9]{1,3}"
+	cat <<-EOF | grep -E $IP_REGEX
 		$server
 		$SERVER
 		$WAN_BP_IP
@@ -173,7 +173,7 @@ while getopts ":s:l:S:L:i:I:e:a:b:w:ouUfh" arg; do
 		s)
 			command -v dig > /dev/null &&
 				server=$(dig +short $OPTARG) ||
-				if [[ $OPTARG =~ $REGEX ]]
+				if ! [[ $OPTARG =~ $IP_REGEX ]]
 				then
 					loger 3 "Hostname detected for server but no dig present to resolve!"
 					exit 1
@@ -187,7 +187,7 @@ while getopts ":s:l:S:L:i:I:e:a:b:w:ouUfh" arg; do
 		S)
 			command -v dig > /dev/null &&
 				SERVER=$(dig +short $OPTARG) ||
-				if [[ $OPTARG =~ $REGEX ]]
+				if ! [[ $OPTARG =~ $IP_REGEX ]]
 				then
 					loger 3 "Hostname detected for UDP server but no dig present to resolve!"
 					exit 1