From 1c00df24a4301ba4937e26bc5a23cf72489fe384 Mon Sep 17 00:00:00 2001
From: roboogg133 <Luizfernandojoaquimdasilva@proton.me>
Date: Sat, 13 Sep 2025 23:11:48 -0300
Subject: [PATCH] Added ask for lan function

---
 cmd/packets/main.go  | 79 ++++++++++++++++++++++++++++++++++++++++++--
 go.mod               |  3 +-
 go.sum               |  6 ++--
 internal/internal.go |  9 +++++
 4 files changed, 91 insertions(+), 6 deletions(-)

diff --git a/cmd/packets/main.go b/cmd/packets/main.go
index c14322c..651c0f3 100644
--- a/cmd/packets/main.go
+++ b/cmd/packets/main.go
@@ -7,22 +7,25 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"net"
 	"os"
 	"packets/internal"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"time"
 
 	"github.com/klauspost/compress/zstd"
 	"github.com/pelletier/go-toml/v2"
 	"github.com/spf13/cobra"
+	"golang.org/x/net/ipv4"
 	_ "modernc.org/sqlite"
 )
 
 // Consts
 
 const DefaultLinux_d = "/etc/packets"
-const DefaultLANDeadline = 2 * time.Second
+const LANDeadline = 2 * time.Second
 
 // Errors
 
@@ -39,6 +42,11 @@ type ConfigTOML struct {
 	} `toml:"Config"`
 }
 
+type Peer struct {
+	IP   net.IP
+	Port int
+}
+
 // init is doing some verifications
 func init() {
 
@@ -183,7 +191,72 @@ func Install(file *os.File) error {
 	return nil
 }
 
-// COBRA CMDS
+func AskLAN(filename string) ([]Peer, error) {
+	var peers []Peer
+	query := []byte("Q:" + filename)
 
+	pc, err := net.ListenPacket("udp", ":0")
+	if err != nil {
+		return []Peer{}, err
+	}
+	defer pc.Close()
+
+	if pconn := ipv4.NewPacketConn(pc); pconn != nil {
+		_ = pconn.SetTTL(1)
+	}
+
+	ifaces, _ := net.Interfaces()
+	for _, ifc := range ifaces {
+		if ifc.Flags&net.FlagUp == 0 || ifc.Flags&net.FlagLoopback != 0 {
+			continue
+		}
+
+		addrs, _ := ifc.Addrs()
+		for _, a := range addrs {
+			ipnet, ok := a.(*net.IPNet)
+			if !ok || ipnet.IP.To4() == nil {
+				continue
+			}
+
+			bcast := internal.BroadcastAddr(ipnet.IP.To4(), ipnet.Mask)
+			dst := &net.UDPAddr{IP: bcast, Port: 1333}
+
+			_, err = pc.WriteTo(query, dst)
+			if err != nil {
+				fmt.Printf(":: (%s) can't send to  %s: %s\n", ifc.Name, bcast, err.Error())
+			}
+		}
+	}
+	_ = pc.SetDeadline(time.Now().Add(LANDeadline))
+	buf := make([]byte, 1500)
+
+	for {
+		n, addr, err := pc.ReadFrom(buf)
+		if err != nil {
+			break
+		}
+		msg := string(buf[:n])
+
+		if strings.HasPrefix(msg, "H:"+filename) {
+			parts := strings.Split(msg, ":")
+			port, _ := strconv.Atoi(parts[2])
+			peers = append(peers, Peer{IP: addr.(*net.UDPAddr).IP, Port: port})
+		}
+	}
+	return peers, nil
+}
+
+// COBRA CMDS
 var rootCmd = &cobra.Command{Use: "packets"}
-var installCmd = &cobra.Command{}
+var installCmd = &cobra.Command{
+	Use:   "install {package} [packages...]",
+	Short: "Install a package",
+	Args:  cobra.MinimumNArgs(1),
+	Run: func(cmd *cobra.Command, args []string) {
+
+	},
+}
+
+func main() {
+	rootCmd.AddCommand(installCmd)
+}
diff --git a/go.mod b/go.mod
index d0f9cd2..4320de3 100644
--- a/go.mod
+++ b/go.mod
@@ -7,6 +7,7 @@ require (
 	github.com/pelletier/go-toml/v2 v2.2.4
 	github.com/spf13/cobra v1.10.1
 	github.com/yuin/gopher-lua v1.1.1
+	golang.org/x/net v0.44.0
 	modernc.org/sqlite v1.38.2
 )
 
@@ -19,7 +20,7 @@ require (
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	github.com/spf13/pflag v1.0.10 // indirect
 	golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b // indirect
-	golang.org/x/sys v0.34.0 // indirect
+	golang.org/x/sys v0.36.0 // indirect
 	modernc.org/libc v1.66.3 // indirect
 	modernc.org/mathutil v1.7.1 // indirect
 	modernc.org/memory v1.11.0 // indirect
diff --git a/go.sum b/go.sum
index 587d32a..59f68be 100644
--- a/go.sum
+++ b/go.sum
@@ -29,11 +29,13 @@ golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b h1:M2rDM6z3Fhozi9O7NWsxAkg/y
 golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b/go.mod h1:3//PLf8L/X+8b4vuAfHzxeRUl04Adcb341+IGKfnqS8=
 golang.org/x/mod v0.25.0 h1:n7a+ZbQKQA/Ysbyb0/6IbB1H/X41mKgbhfv7AfG/44w=
 golang.org/x/mod v0.25.0/go.mod h1:IXM97Txy2VM4PJ3gI61r1YEk/gAj6zAHN3AdZt6S9Ww=
+golang.org/x/net v0.44.0 h1:evd8IRDyfNBMBTTY5XRF1vaZlD+EmWx6x8PkhR04H/I=
+golang.org/x/net v0.44.0/go.mod h1:ECOoLqd5U3Lhyeyo/QDCEVQ4sNgYsqvCZ722XogGieY=
 golang.org/x/sync v0.15.0 h1:KWH3jNZsfyT6xfAfKiz6MRNmd46ByHDYaZ7KSkCtdW8=
 golang.org/x/sync v0.15.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
 golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.34.0 h1:H5Y5sJ2L2JRdyv7ROF1he/lPdvFsd0mJHFw2ThKHxLA=
-golang.org/x/sys v0.34.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k=
+golang.org/x/sys v0.36.0 h1:KVRy2GtZBrk1cBYA7MKu5bEZFxQk4NIDV6RLVcC8o0k=
+golang.org/x/sys v0.36.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/tools v0.34.0 h1:qIpSLOxeCYGg9TrcJokLBG4KFA6d795g0xkBkiESGlo=
 golang.org/x/tools v0.34.0/go.mod h1:pAP9OwEaY1CAW3HOmg3hLZC5Z0CCmzjAF2UQMSqNARg=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
diff --git a/internal/internal.go b/internal/internal.go
index 6adf057..8651ef4 100644
--- a/internal/internal.go
+++ b/internal/internal.go
@@ -5,6 +5,7 @@ import (
 	"errors"
 	"io"
 	"log"
+	"net"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -150,3 +151,11 @@ func GetConfigTOML() (*ConfigTOML, error) {
 
 	return &config, nil
 }
+
+func BroadcastAddr(ip net.IP, mask net.IPMask) net.IP {
+	b := make(net.IP, len(ip))
+	for i := range ip {
+		b[i] = ip[i] | ^mask[i]
+	}
+	return b
+}