changed net module to net/netip and added file ops

cmd/ip-add.go

@@ -6,7 +6,7 @@ package cmd
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 	"os"
 
 	"github.com/spf13/cobra"
@@ -29,30 +29,42 @@ var ipaddCmd = &cobra.Command{
 			hostname = args[1]
 		}
 
-		ip := net.ParseIP(ipaddress)
+		ip, parseerr := netip.ParseAddr(ipaddress)
 
 		// Exit if parsed value is no valid IP
-		if ip == nil {
+		if parseerr != nil {
-			fmt.Printf("[ERROR] not a valid IP: %v\n", ipaddress)
+			fmt.Println("[ERROR]", parseerr)
 			os.Exit(1)
 		}
 
 		// Exit if parsed value is an IPv6 Address
 		// TODO: Implement IPv6 support
-		if ip.To4() == nil {
+		if !ip.Is4() {
 			fmt.Printf("[ERROR] IPv6 is not yet supported!\n")
 			os.Exit(1)
 		}
 
-		// TODO: Check if there is already a subnet that can contain this IP, err if not
+		subnet, subnetexists := SearchBestSubnet(ip)
 
-		if hostname == "" {
+		if !subnetexists {
-			fmt.Printf("Adding IP %v\n", ipaddress)
+			fmt.Printf("[ERROR] Found no suitable subnet for IP %v\n", ipaddress)
-		} else {
+			fmt.Printf("[ERROR] Maybe you need to add it first?\n")
-			fmt.Printf("Adding IP %v with hostname %v\n", ipaddress, hostname)
+			os.Exit(1)
 		}
 
-		// TODO: Save to file
+		subnet.Addresses = append(subnet.Addresses, Address{ip.String(), hostname})
+
+		writeerr := WriteSubnet(subnet)
+		if writeerr != nil {
+			fmt.Println("[ERROR]", writeerr)
+			os.Exit(1)
+		}
+
+		if hostname == "" {
+			fmt.Printf("added ip:\nip: %v\n", ipaddress)
+		} else {
+			fmt.Printf("added ip:\nip: %v\nhostname: %v\n", ipaddress, hostname)
+		}
 	},
 }
 

cmd/root.go

@@ -84,7 +84,4 @@ func initConfig() {
 			println("[ERROR] Can't read config file!", err)
 		}
 	}
-
-	fmt.Println(viper.AllKeys())
-
 }

cmd/storage.go

@@ -5,11 +5,17 @@ Copyright © 2023 Laura Kalb <dev@lauka.net>
 package cmd
 
 import (
-	"net"
+	"bufio"
+	"fmt"
+	"net/netip"
+	"os"
+	"strings"
+
+	"github.com/spf13/viper"
 )
 
 type Subnet struct {
-	Subnet    net.IPNet
+	Subnet    netip.Prefix
 	Name      string
 	Vlan      string
 	Addresses []Address
@@ -20,15 +26,76 @@ type Address struct {
 	FQDN string
 }
 
-// GetSubnet tries to load the most fitting IP subnet file on disk.
+// SearchBestSubnet tries to load the most fitting IP subnet file
-// It takes an IP object and tries to get the best subnet (meaning
+// on disk. It takes an IP object and tries to get the best subnet
-// the subnet with the smallest subnet size).
+// (meaning the subnet with the smallest subnet size).
 //
 // Returns the best subnet as Subnet object and true if a suitable
 // subnet was found, otherwise an empty Subnet object and false.
-func GetSubnet(ip net.IP) (Subnet, bool) {
+func SearchBestSubnet(ip netip.Addr) (Subnet, bool) {
+	subnets := ListSubnets()
+	var smallestprefix int = 0
+	bestmatch, _ := netip.ParsePrefix("0.0.0.0/32")
+	var isipv4 bool = ip.Is4()
+	var subnet Subnet
 
+	for _, net := range subnets {
+		prefix, _ := netip.ParsePrefix(net)
+		if prefix.Addr().Is4() == isipv4 {
+			if prefix.Contains(ip) {
+				if prefix.Bits() > smallestprefix {
+					bestmatch = prefix
+				}
+			}
+		}
+	}
+	if !bestmatch.Addr().IsUnspecified() {
+		var geterr error
+		subnet, geterr = GetSubnet(bestmatch)
+		if geterr != nil {
+			fmt.Println("[ERROR]", geterr)
+			os.Exit(1)
+		}
+		return subnet, true
+	} else {
 		return Subnet{}, false
+	}
+}
+
+// SubnetExists will return true if the given subnet already exists
+// on file, false otherwise.
+func SubnetExists(net netip.Prefix) bool {
+	subnets := ListSubnets()
+
+	for _, b := range subnets {
+		if b == net.String() {
+			return true
+		}
+	}
+	return false
+}
+
+// ListSubnets returns a list of strings containing the current
+// subnets configured.
+func ListSubnets() []string {
+	subnets := make([]string, 0)
+	var datadir string = viper.GetString("DataPath")
+
+	subnetfiles, readerr := os.ReadDir(datadir)
+
+	if len(subnetfiles) == 0 {
+		return subnets
+	}
+
+	if readerr != nil {
+		fmt.Println("[ERROR]", readerr)
+		os.Exit(1)
+	}
+	for _, element := range subnetfiles {
+		subnets = append(subnets, strings.Replace(element.Name(), "_", "/", 1))
+	}
+
+	return subnets
 }
 
 // WriteSubnet takes a given Subnet object and tries to write it to
@@ -36,7 +103,101 @@ func GetSubnet(ip net.IP) (Subnet, bool) {
 //
 // Returns nil on success or the error that happened.
 func WriteSubnet(subnet Subnet) error {
-	//if subnet.Subnet
+	var datadir string = viper.GetString("DataPath")
+
+	_, direrr := os.Stat(datadir)
+	if direrr != nil {
+		mkerr := os.MkdirAll(datadir, 0755)
+		if mkerr != nil {
+			println("[ERROR] Can't create ipam config directory!", mkerr)
+			os.Exit(1)
+		}
+	}
+
+	filename := datadir + strings.Replace(subnet.Subnet.String(), "/", "_", 1)
+
+	file, fileerr := os.Create(filename)
+	if fileerr != nil {
+		fmt.Println("[ERROR]", fileerr)
+		os.Exit(1)
+	}
+	defer file.Close()
+
+	_, suberr := file.WriteString(subnet.Subnet.String() + "\n")
+	if suberr != nil {
+		fmt.Println("[ERROR]", suberr)
+		os.Exit(1)
+	}
+
+	_, nameerr := file.WriteString(subnet.Name + "\n")
+	if nameerr != nil {
+		fmt.Println("[ERROR]", nameerr)
+		os.Exit(1)
+	}
+
+	_, vlanerr := file.WriteString(subnet.Vlan + "\n")
+	if vlanerr != nil {
+		fmt.Println("[ERROR]", vlanerr)
+		os.Exit(1)
+	}
+
+	if len(subnet.Addresses) != 0 {
+		for _, element := range subnet.Addresses {
+			_, err := file.WriteString(element.IP + ":" + element.FQDN + "\n")
+			if err != nil {
+				fmt.Println("[ERROR]", err)
+				os.Exit(1)
+			}
+		}
+	}
 
 	return nil
 }
+
+// GetSubnet reads the corresponding file for the given
+// netip.Prefix net and constructs a Subnet object.
+//
+// Returns the Subnet object and nil if the file read was
+// successful, an empty Subnet object and the error otherwise.
+func GetSubnet(net netip.Prefix) (Subnet, error) {
+	var datadir string = viper.GetString("DataPath")
+	filename := datadir + strings.Replace(net.String(), "/", "_", 1)
+	var subnet Subnet = Subnet{}
+
+	// open file
+	file, openerr := os.Open(filename)
+	if openerr != nil {
+		return Subnet{}, openerr
+	}
+	// remember to close the file at the end of the program
+	defer file.Close()
+
+	// read the file line by line using scanner
+	scanner := bufio.NewScanner(file)
+
+	var counter int = 0
+	for scanner.Scan() {
+		switch counter {
+		case 0:
+			subnet.Subnet, _ = netip.ParsePrefix(scanner.Text())
+
+		case 1:
+			subnet.Name = scanner.Text()
+
+		case 2:
+			subnet.Vlan = scanner.Text()
+
+		default:
+			s := strings.Split(scanner.Text(), ":")
+			a := Address{s[0], s[1]}
+			subnet.Addresses = append(subnet.Addresses, a)
+		}
+		counter = counter + 1
+	}
+
+	if scanerr := scanner.Err(); scanerr != nil {
+		return Subnet{}, openerr
+	}
+
+	return subnet, nil
+}

cmd/subnet-add.go

@@ -6,7 +6,7 @@ package cmd
 
 import (
 	"fmt"
-	"net"
+	"net/netip"
 	"os"
 
 	"github.com/spf13/cobra"
@@ -14,29 +14,37 @@ import (
 
 // addCmd represents the add command
 var subnetaddCmd = &cobra.Command{
-	Use:     "add subnet [vlan]",
+	Use:     "add subnet subnet-name [vlan]",
 	Short:   "Add a new subnet",
 	Long:    `Add a new subnet`,
-	Args:    cobra.RangeArgs(1, 2),
+	Args:    cobra.RangeArgs(2, 3),
 	Aliases: []string{"a"},
 	Run: func(cmd *cobra.Command, args []string) {
 		var subnet string
 		var vlanid string
 		var netname string
 
-		if len(args) == 1 {
+		if len(args) == 2 {
 			subnet = args[0]
-
+			netname = args[1]
 			vlanid = "-"
 		}
 
-		if len(args) == 2 {
+		if len(args) == 3 {
 			subnet = args[0]
-			vlanid = args[1]
+			netname = args[1]
+			vlanid = args[2]
 		}
 
 		// Parse subnet into ParseCIDR to test if it's a valid subnet
-		_, ipnet, err := net.ParseCIDR(subnet)
+		// _, ipnet, err := net.ParseCIDR(subnet)
+		ipnet, err := netip.ParsePrefix(subnet)
+
+		// Exit if subnet already exists, no need to add it then
+		if SubnetExists(ipnet) {
+			fmt.Printf("[ERROR] Subnet already exists: %v\n", subnet)
+			os.Exit(1)
+		}
 
 		// Exit if parsed value is no valid IP
 		if err != nil {
@@ -46,23 +54,28 @@ var subnetaddCmd = &cobra.Command{
 
 		// Exit if parsed value is an IPv6 Address
 		// TODO: Implement IPv6 support
-		if ipnet.IP.To4() == nil {
+		if !ipnet.Addr().Is4() {
 			fmt.Printf("[ERROR] IPv6 is not yet supported!\n")
 			os.Exit(1)
 		}
 
-		// Ask for Subnet Name
+		subnetobject := Subnet{}
-		// TODO: Check if net name only contains letters, numbers and hyphens
+		subnetobject.Subnet = ipnet
-		fmt.Printf("Subnet name: ")
+		subnetobject.Name = netname
-		fmt.Scan(&netname)
+		subnetobject.Vlan = vlanid
 
-		if vlanid == "-" {
+		writeerr := WriteSubnet(subnetobject)
-			fmt.Printf("Adding Subnet %v.\n", subnet)
+
-		} else {
+		if writeerr != nil {
-			fmt.Printf("Adding Subnet %v with VLAN Tag %v.\n", subnet, vlanid)
+			fmt.Println("[ERROR]", err)
+			os.Exit(1)
 		}
 
-		// TODO: Save subnet to file
+		if vlanid == "-" {
+			fmt.Printf("added subnet:\nnet: %v\nname: %v\n", subnet, netname)
+		} else {
+			fmt.Printf("added subnet:\nnet: %v\nname: %v\nvlan: %v\n", subnet, netname, vlanid)
+		}
 	},
 }