Feature: add source ipcidr condition for all rules

rule/base.go

@@ -2,6 +2,8 @@ package rules
 
 import (
 	"errors"
+	"net"
+	"strings"
 
 	C "github.com/Dreamacro/clash/constant"
 )
@@ -14,6 +16,7 @@ var (
 
 func HasNoResolve(params []string) bool {
 	for _, p := range params {
+		p = strings.Trim(p, " ")
 		if p == noResolve {
 			return true
 		}
@@ -23,6 +26,7 @@ func HasNoResolve(params []string) bool {
 
 func findNetwork(params []string) C.NetWork {
 	for _, p := range params {
+		p = strings.Trim(p, " ")
 		if p == "tcp" {
 			return C.TCP
 		} else if p == "udp" {
@@ -31,3 +35,23 @@ func findNetwork(params []string) C.NetWork {
 	}
 	return C.ALLNet
 }
+
+func findSourceIPs(params []string) []*net.IPNet {
+	var ips []*net.IPNet
+	for _, p := range params {
+		p = strings.Trim(p, " ")
+		if p == noResolve || len(p) < 7 {
+			continue
+		}
+		_, ipnet, err := net.ParseCIDR(p)
+		if err != nil {
+			continue
+		}
+		ips = append(ips, ipnet)
+	}
+
+	if len(ips) > 0 {
+		return ips
+	}
+	return nil
+}