From b7df69d1cc26b165ef04961a28d648a99b5b262e Mon Sep 17 00:00:00 2001
From: Ryou Kawabata <ryou.kawabata@link-u.co.jp>
Date: Thu, 4 Aug 2022 22:32:42 +0900
Subject: [PATCH 1/2] =?UTF-8?q?ipv4=E3=82=A2=E3=83=89=E3=83=AC=E3=82=B9?=
 =?UTF-8?q?=E3=81=AE=E7=AE=97=E5=87=BA=E3=81=ABnet=E3=83=91=E3=83=83?=
 =?UTF-8?q?=E3=82=B1=E3=83=BC=E3=82=B8=E3=82=92=E5=88=A9=E7=94=A8?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 cmd/subspace/utils.go | 59 +++++++++++++++++++------------------------
 1 file changed, 26 insertions(+), 33 deletions(-)

diff --git a/cmd/subspace/utils.go b/cmd/subspace/utils.go
index f7b2372..444421b 100644
--- a/cmd/subspace/utils.go
+++ b/cmd/subspace/utils.go
@@ -12,6 +12,7 @@ import (
 	"path/filepath"
 	"text/template"
 	"time"
+	"net"
 	"strconv"
 	"strings"
 )
@@ -72,37 +73,29 @@ set -o xtrace
 }
 
 func ipv4address(Number int,IPv4_POOL string) (string,error) {
-    var err error = nil
-    
-    var hostcidrS[] string = strings.Split(IPv4_POOL,"/")
-    cidr, _ := strconv.Atoi(hostcidrS[1])
-    subnet := ((1<<cidr)-1)
-    subnetmask := ((1<<32)-1)^subnet
-    
-    var hostOctetS[] string = strings.Split(hostcidrS[0],".")
-    var hostOctet[4] int
-    hostOctet[0], _=strconv.Atoi(hostOctetS[0])
-    hostOctet[1], _=strconv.Atoi(hostOctetS[1])
-    hostOctet[2], _=strconv.Atoi(hostOctetS[2])
-    hostOctet[3], _=strconv.Atoi(hostOctetS[3])
-    host := (hostOctet[0]<<24)|(hostOctet[1]<<16)|(hostOctet[2]<<8)|(hostOctet[3]<<0)
-    
-    ip := host|Number
-    ipOctet := [4]int {(ip>>24)&255, (ip>>16)&255, (ip>>8)&255, (ip>>0)&255}
-    
-    var ipS string = fmt.Sprintf("%d.%d.%d.%d",ipOctet[0],ipOctet[1],ipOctet[2],ipOctet[3])
-    
-    if (host&subnet) != 0 {
-        err = fmt.Errorf("IPv4_POOL=\"%s\"",IPv4_POOL)
-    }else if (Number&subnetmask) != 0 {
-        err = fmt.Errorf("Number does not fit in the POOL. Number=%d, POOL=\"/%d\"",Number,cidr)
-    }else if Number == subnet {
-        err = fmt.Errorf("Broadcast address. Number=%d, IPv4_POOL=\"%s\", address=\"%s\"",Number,IPv4_POOL,ipS)
-    }else if Number == 0 {
-        err = fmt.Errorf("Network address. Number=%d, IPv4_POOL=\"%s\", address=\"%s\"",Number,IPv4_POOL,ipS)
-    }
-    
-    return ipS,err
+        _, ipnet, err := net.ParseCIDR(IPv4_POOL)
+        
+        if err != nil {
+            return "",err
+        }
+        
+        var int64ip int64 =
+                int64(ipnet.IP[0])*256*256*256+
+                int64(ipnet.IP[1])*256*256+
+                int64(ipnet.IP[2])*256+
+                int64(ipnet.IP[3])+
+                int64(Number)
+        
+        var ip net.IP = net.IPv4(
+                byte(int64ip/256/256/256),
+                byte(int64ip/256/256%256),
+                byte(int64ip/256%256),
+                byte(int64ip%256),
+        )
+        
+        if !ipnet.Contains(ip) {
+                return "",fmt.Errorf("%d hosts can't fit in network %s.",Number,ipnet)
+        }
+        
+        return fmt.Sprint(ip),nil
 }
-
-

From d50dd0fca38377a185578e65d714aa68bbbd025b Mon Sep 17 00:00:00 2001
From: Ryou Kawabata <ryou.kawabata@link-u.co.jp>
Date: Thu, 4 Aug 2022 22:36:58 +0900
Subject: [PATCH 2/2] =?UTF-8?q?=E4=B8=8D=E8=A6=81=E3=81=AB=E3=81=AA?=
 =?UTF-8?q?=E3=81=A3=E3=81=9F=E3=83=91=E3=83=83=E3=82=B1=E3=83=BC=E3=82=B8?=
 =?UTF-8?q?=E3=81=AEimport=E3=82=92=E3=82=84=E3=82=81=E3=81=9F?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 cmd/subspace/utils.go | 2 --
 1 file changed, 2 deletions(-)

diff --git a/cmd/subspace/utils.go b/cmd/subspace/utils.go
index 444421b..78083b4 100644
--- a/cmd/subspace/utils.go
+++ b/cmd/subspace/utils.go
@@ -13,8 +13,6 @@ import (
 	"text/template"
 	"time"
 	"net"
-	"strconv"
-	"strings"
 )
 
 func RandomString(n int) string {