added Dns server

blackhatgo/chapter4/fileServer.go

@@ -0,0 +1,5 @@
+package main
+
+func main(){
+
+}

blackhatgo/chapter5/dnsServer.go

@@ -0,0 +1,70 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/miekg/dns"
+)
+
+var records map[string]string
+
+func parse(filename string) (map[string]string, error) {
+	records := make(map[string]string)
+	fh, err := os.Open(filename)
+	if err != nil {
+		return records, err
+	}
+	defer fh.Close()
+	scanner := bufio.NewScanner(fh)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.SplitN(line, ",", 2)
+		if len(parts) < 2 {
+			return records, fmt.Errorf("%s is not a valid line", line)
+		}
+		records[parts[0]] = parts[1]
+	}
+	return records, scanner.Err()
+
+}
+
+func dnsRequestHandler(w dns.ResponseWriter, req *dns.Msg) {
+	msg := dns.Msg{}
+	msg.SetReply(req)
+	if len(req.Question) < 1 {
+		dns.HandleFailed(w, req)
+		return
+	}
+	name := strings.TrimSuffix(req.Question[0].Name, ".")
+	parts := strings.Split(name, ".")
+
+	if len(parts) > 1 {
+		name = strings.Join(parts[len(parts)-2:], ".")
+	}
+	match, ok := records[name]
+	fmt.Println(match)
+	if !ok {
+		dns.HandleFailed(w, req)
+		return
+	}
+	resp
+	if err != nil {
+		dns.HandleFailed(w, req)
+		return
+	}
+	if err := w.WriteMsg(resp); err != nil {
+		dns.HandleFailed(w, req)
+		return
+	}
+}
+
+func main() {
+	records, _ = parse("proxy.config")
+
+	dns.HandleFunc(".", dnsRequestHandler)
+	log.Fatal(dns.ListenAndServe(":53", "udp", nil))
+}

blackhatgo/chapter5/go.mod

@@ -0,0 +1,9 @@
+module github.com/vanshaj/golang/blackhatgo/chapter5
+
+go 1.17
+
+require (
+	github.com/miekg/dns v1.1.43 // indirect
+	golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 // indirect
+	golang.org/x/sys v0.0.0-20210303074136-134d130e1a04 // indirect
+)

blackhatgo/chapter5/go.sum

@@ -0,0 +1,11 @@
+github.com/miekg/dns v1.1.43 h1:JKfpVSCB84vrAmHzyrsxB5NAr5kLoMXZArPSw7Qlgyg=
+github.com/miekg/dns v1.1.43/go.mod h1:+evo5L0630/F6ca/Z9+GAqzhjGyn8/c+TBaOyfEl0V4=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 h1:qWPm9rbaAMKs8Bq/9LRpbMqxWRVUAQwMI9fVrssnTfw=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210303074136-134d130e1a04 h1:cEhElsAv9LUt9ZUUocxzWe05oFLVd+AA2nstydTeI8g=
+golang.org/x/sys v0.0.0-20210303074136-134d130e1a04/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

blackhatgo/chapter5/proxy.config

@@ -0,0 +1,2 @@
+attacker1.com,127.0.0.1:2021
+attacker2.com,127.0.0.1:2022

blackhatgo/chapter5/wordlist

@@ -0,0 +1,11 @@
+qa1
+qa3
+qa7
+qa8
+qa9
+qa10
+abc
+def
+xyz
+hhh
+mnh