lcg unique distribution improvement

common/lcg.go

@@ -1,6 +1,8 @@
 package common
 
 import (
+	"crypto/rand"
+	"encoding/binary"
 	"fmt"
 	"math/big"
 	"net"
@@ -19,6 +21,14 @@ func toip(num uint32) string {
 		num&255)
 }
 
+func seed() int64 {
+	var n int64
+	if err := binary.Read(rand.Reader, binary.LittleEndian, &n); err != nil {
+		return 1337
+	}
+	return n
+}
+
 // per-cidr linear congruential generator for efficient randomized target ip ordering, ty claude
 func LCG(cidr string, out chan<- string) {
 	// lcg constants
@@ -27,11 +37,10 @@ func LCG(cidr string, out chan<- string) {
 
 	_, ipnet, _ := net.ParseCIDR(cidr)
 	start := iptouint(ipnet.IP)
-
 	ones, bits := ipnet.Mask.Size()
 	addrcount := new(big.Int).Lsh(big.NewInt(1), uint(bits-ones))
 
-	x := uint64(start)
+	x := uint64(seed()) ^ uint64(start) // seed for unique randomization per execution
 	m := uint64(addrcount.Uint64())
 
 	for i := uint64(0); i < m; i++ {