initial commit - no hmac

4 years ago · 6457bd2089
parent 04bbbbe486
commit 6457bd2089
1 changed files with 294 additions and 0 deletions
--- a/d4-goclient.go
+++ b/d4-goclient.go
@ -0,0 +1,294 @@
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"strconv"
+	"time"
+
+	//BSD 3
+	uuid "github.com/satori/go.uuid"
+)
+
+const (
+	// Version Size
+	VERSION_SIZE = 1
+	// Type Size
+	TYPE_SIZE = 1
+	// UUID v4 Size
+	UUID_SIZE = 16
+	// Timestamp Size
+	TIMESTAMP_SIZE = 8
+	// HMAC-SHA256 MAC Size
+	HMAC_SIZE = 32
+	// Payload size Size
+	SSIZE = 4
+
+	HDR_SIZE = VERSION_SIZE + TYPE_SIZE + UUID_SIZE + HMAC_SIZE + TIMESTAMP_SIZE + SSIZE
+)
+
+type (
+
+	// A d4 writer implements the io.Writer Interface by implementing Write() and Close()
+	// it accepts an io.Writer as sink
+	d4Writer struct {
+		w io.Writer
+	}
+
+	d4S struct {
+		src       io.Reader
+		dst       io.Writer
+		confdir   string
+		d4error   uint8
+		errnoCopy uint8
+		conf      d4params
+		//header    d4Header
+		d4header []byte
+		payload  []byte
+	}
+
+	d4params struct {
+		uuid        []byte
+		snaplen     uint32
+		key         string
+		version     uint8
+		source      string
+		destination string
+		ttype       uint8
+	}
+)
+
+var (
+	// verbose
+	buf    bytes.Buffer
+	logger = log.New(&buf, "INFO: ", log.Lshortfile)
+	infof  = func(info string) {
+		logger.Output(2, info)
+	}
+
+	confdir = flag.String("c", "", "configuration directory")
+	debug   = flag.Bool("v", false, "Set to True, true, TRUE, 1, or t to enable verbose output on stdout")
+)
+
+func newD4Writer(writer io.Writer) *d4Writer {
+	return &d4Writer{w: writer}
+}
+
+func main() {
+
+	var d4 d4S
+	d4p := &d4
+
+	flag.Usage = func() {
+		fmt.Printf("d4 - d4 client\n")
+		fmt.Printf("Read data from the configured <source> and send it to <destination>\n")
+		fmt.Printf("\n")
+		fmt.Printf("Usage: d4 -c  config_directory\n")
+		fmt.Printf("\n")
+		fmt.Printf("Configuration\n\n")
+		fmt.Printf("The configuration settings are stored in files in the configuration directory\n")
+		fmt.Printf("specified with the -c command line switch.\n\n")
+		fmt.Printf("Files in the configuration directory\n")
+		fmt.Printf("\n")
+		fmt.Printf("key         - is the private HMAC-SHA-256-128 key.\n")
+		fmt.Printf("              The HMAC is computed on the header with a HMAC value set to 0\n")
+		fmt.Printf("              which is updated later.\n")
+		fmt.Printf("snaplen     - the length of bytes that is read from the <source>\n")
+		fmt.Printf("version     - the version of the d4 client\n")
+		fmt.Printf("type        - the type of data that is send. pcap, netflow, ...\n")
+		fmt.Printf("source      - the source where the data is read from\n")
+		fmt.Printf("destination - the destination where the data is written to\n")
+		fmt.Printf("\n")
+		fmt.Printf("-v [TRUE] for verbose output on stdout")
+		flag.PrintDefaults()
+	}
+
+	flag.Parse()
+	if flag.NFlag() == 0 || *confdir == "" {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	// Output logging before closing if debug is enabled
+	if *debug == true {
+		defer fmt.Print(&buf)
+	}
+
+	d4.confdir = *confdir
+	//var d4 = d4loadConfig(confdir)
+	if d4loadConfig(d4p) == true {
+		initHeader(d4p)
+		//d4transfer(d4p)
+	}
+}
+
+func readConfFile(d4 *d4S, fileName string) []byte {
+	f, err := os.Open((*d4).confdir + "/" + fileName)
+	if err != nil {
+		log.Fatal(err)
+	}
+	data := make([]byte, 100)
+	count, err := f.Read(data)
+	if err != nil {
+		if err != io.EOF {
+			log.Fatal(err)
+		}
+	}
+	infof(fmt.Sprintf("read %d bytes: %q\n", count, data[:count]))
+	if err := f.Close(); err != nil {
+		log.Fatal(err)
+	}
+	// removes 1 for \n
+	return data[:count-1]
+}
+
+func d4loadConfig(d4 *d4S) bool {
+	// populate the map
+	(*d4).conf = d4params{}
+	(*d4).conf.source = string(readConfFile(d4, "source"))
+	(*d4).conf.destination = string(readConfFile(d4, "destination"))
+	(*d4).conf.uuid = readConfFile(d4, "uuid")
+	// parse snaplen to uint32
+	tmp, _ := strconv.ParseUint(string(readConfFile(d4, "snaplen")), 10, 32)
+	(*d4).conf.snaplen = uint32(tmp)
+	(*d4).conf.key = string(readConfFile(d4, "key"))
+	// parse version to uint8
+	tmp, _ = strconv.ParseUint(string(readConfFile(d4, "version")), 10, 8)
+	(*d4).conf.version = uint8(tmp)
+	// parse type to uint8
+	tmp, _ = strconv.ParseUint(string(readConfFile(d4, "type")), 10, 8)
+	(*d4).conf.ttype = uint8(tmp)
+	return d4checkConfig(d4)
+}
+
+// QUICK IMPLEM, REVISE
+func d4checkConfig(d4 *d4S) bool {
+
+	//TODO implement other destination file, fifo unix_socket ...
+	switch (*d4).conf.source {
+	case "stdin":
+		(*d4).src = os.Stdin
+	case "pcap":
+		f, _ := os.Open("capture.pcap")
+		(*d4).src = f
+	}
+
+	switch (*d4).conf.destination {
+	case "stdout":
+		(*d4).dst = newD4Writer(os.Stdout)
+	case "file":
+		f, _ := os.Create("test.txt")
+		(*d4).dst = newD4Writer(f)
+	}
+
+	if len((*d4).conf.uuid) == 0 {
+		// UUID not set, generate a new one
+		(*d4).conf.uuid = generateUUIDv4()
+		// And push it into the conf file
+		f, err := os.OpenFile((*d4).confdir+"/uuid", os.O_WRONLY|os.O_CREATE, 0666)
+		if err != nil {
+			log.Fatal(err)
+		}
+		f.WriteString(string((*d4).conf.uuid) + "\n")
+		f.Close()
+	}
+
+	return true
+}
+
+func generateUUIDv4() []byte {
+	uuid, err := uuid.NewV4()
+	if err != nil {
+		log.Fatal(err)
+	}
+	infof(fmt.Sprintf("UUIDv4: %s\n", uuid))
+	return []byte(uuid[:])
+}
+
+//TODO turn this ugly mess into a Framer
+func initHeader(d4 *d4S) bool {
+	// zero out the header
+	(*d4).d4header = make([]byte, HDR_SIZE)
+	// put version a type into the header
+	(*d4).d4header[0] = (*d4).conf.version
+	(*d4).d4header[1] = (*d4).conf.ttype
+	// put uuid into the header
+	ps := 2
+	pe := ps + UUID_SIZE
+	copy((*d4).d4header[ps:pe], (*d4).conf.uuid)
+	// timestamp
+	timeUnix := time.Now().UnixNano()
+	ps = pe
+	pe = ps + TIMESTAMP_SIZE
+	binary.LittleEndian.PutUint64((*d4).d4header[ps:pe], uint64(timeUnix))
+	// hmac is set to zero during hmac operations, so leave it alone
+	// still, we move the pointers
+	ps = pe
+	pe = ps + HMAC_SIZE
+	ps = pe
+	pe = ps + 4
+	// TODO put nread size instead of snaplen
+	binary.LittleEndian.PutUint32((*d4).d4header[ps:pe], (*d4).conf.snaplen)
+
+	// LittleEndian
+	// toto := append(make([]byte, 0), byte((*d4).conf.snaplen), byte((*d4).conf.snaplen>>8), byte((*d4).conf.snaplen>>16), byte((*d4).conf.snaplen>>24))
+	// BigEndian
+	// toto := append(make([]byte, 0), byte((*d4).conf.snaplen>>24), byte((*d4).conf.snaplen>>16), byte((*d4).conf.snaplen>>8), byte((*d4).conf.snaplen))
+	// tmpi := binary.BigEndian.Uint32(toto)
+	// tmpt := binary.LittleEndian.Uint32(others)
+	// fmt.Println(tmpi)
+	fmt.Println((*d4).d4header)
+
+	return true
+}
+
+func d4transfer(d4 *d4S) {
+	src := (*d4).src
+	dst := (*d4).dst
+	buf := make([]byte, (*d4).conf.snaplen)
+
+	//for {
+	//n, _ := src.Read(buf)
+	_, _ = src.Read(buf)
+
+	dst.Write(buf)
+
+	// if n > 0 {
+	// update the header
+	// timestamp
+
+	/* 		h := hmac.New(sha256.New, []byte((*d4).conf.key))
+	   		h.Write((*d4).header.version)
+	   		h.Write((*d4).header.ttype)
+	   		h.Write((*d4).header.uuid)
+	   		h.Write((*d4).header.timestamp)
+	   		h.Write((*d4).header.hhmac)
+	   		h.Write((*d4).header.size)
+	   		h.Write([]byte(buf))
+
+	*/ //Add it to the header
+
+	// fmt.Println(base64.StdEncoding.EncodeToString(h.Sum(nil)))
+
+	// Write the packet in the sink
+	//}
+	//fmt.Println(n)
+	//fmt.Println(string(buf))
+	//}
+	//io.Copy((*d4).dst, (*d4).src)
+}
+
+func (d4w *d4Writer) Write(bs []byte) (int, error) {
+	d4w.w.Write(bs)
+	return len(bs), nil
+}
+
+func (d4w *d4Writer) Close() error {
+	// nothing ATM
+	return nil
+}