Added verbose mode, small refactoring

Author: shadowy-pycoder

cmd/mshark/cli.go

@@ -98,7 +98,7 @@ func root(args []string) error {
 	})
 	flags.DurationVar(&conf.Timeout, "t", 0, "The maximum duration of the packet capture process. Example: 5s")
 	flags.IntVar(&conf.PacketCount, "c", 0, "The maximum number of packets to capture.")
-	flags.StringVar(&conf.Expr, "e", "", `BPF filter expression. Example: "ip proto tcp"`)
+	flags.StringVar(&conf.Expr, "e", "", `BPF filter expression. Example: "ip proto tcp".`)
 	flags.BoolFunc("D", "Display list of interfaces and exit.", func(flagValue string) error {
 		if err := displayInterfaces(); err != nil {
 			fmt.Fprintf(os.Stderr, "%s: %v\n", app, err)
@@ -107,6 +107,11 @@ func root(args []string) error {
 		os.Exit(0)
 		return nil
 	})
+	var verbose bool
+	flags.BoolFunc("v", "Display full packet info when capturing to stdout or txt.", func(flagValue string) error {
+		verbose = true
+		return nil
+	})
 	exts := ExtFlag([]string{})
 	flags.TextVar(&exts, "f", &exts, "File extension(s) to write captured data. Supported formats: stdout, txt, pcap, pcapng")
 
@@ -138,7 +143,7 @@ func root(args []string) error {
 		for _, ext := range exts {
 			switch ext {
 			case "stdout":
-				w := ms.NewWriter(os.Stdout)
+				w := ms.NewWriter(os.Stdout, verbose)
 				if err := w.WriteHeader(&conf); err != nil {
 					return err
 				}
@@ -149,7 +154,7 @@ func root(args []string) error {
 					return err
 				}
 				defer f.Close()
-				w := ms.NewWriter(f)
+				w := ms.NewWriter(f, verbose)
 				if err := w.WriteHeader(&conf); err != nil {
 					return err
 				}
@@ -182,7 +187,7 @@ func root(args []string) error {
 			}
 		}
 	} else {
-		w := ms.NewWriter(os.Stdout)
+		w := ms.NewWriter(os.Stdout, verbose)
 		if err := w.WriteHeader(&conf); err != nil {
 			return err
 		}

layers/arp.go

@@ -14,11 +14,13 @@ const headerSizeARP = 28
 // associated with a given internet layer address, typically an IPv4 address.
 // Defined in RFC 826.
 type ARPPacket struct {
-	HardwareType uint16 // Network link protocol type.
-	ProtocolType uint16 // Internetwork protocol for which the ARP request is intended.
-	Hlen         uint8  // Length (in octets) of a hardware address.
-	Plen         uint8  // Length (in octets) of internetwork addresses.
-	Op           uint16 // Specifies the operation that the sender is performing.
+	HardwareType     uint16 // Network link protocol type.
+	ProtocolType     uint16 // Internetwork protocol for which the ARP request is intended.
+	ProtocolTypeDesc string // Internetwork protocol description.
+	Hlen             uint8  // Length (in octets) of a hardware address.
+	Plen             uint8  // Length (in octets) of internetwork addresses.
+	Op               uint16 // Specifies the operation that the sender is performing.
+	OpDesc           string // Operation description.
 	// Media address of the sender. In an ARP request this field is used to indicate
 	// the address of the host sending the request. In an ARP reply this field is used
 	// to indicate the address of the host that the request was looking for.
@@ -31,7 +33,7 @@ type ARPPacket struct {
 }
 
 func (ap *ARPPacket) String() string {
-	return fmt.Sprintf(`ARP Packet:
+	return fmt.Sprintf(`%s
 - Hardware Type: %d
 - Protocol Type: %s (%#04x)
 - HLen: %d
@@ -42,12 +44,13 @@ func (ap *ARPPacket) String() string {
 - Target MAC Address: %s
 - Target IP Address: %s
 `,
+		ap.Summary(),
 		ap.HardwareType,
-		ap.ptype(),
+		ap.ProtocolTypeDesc,
 		ap.ProtocolType,
 		ap.Hlen,
 		ap.Plen,
-		ap.op(),
+		ap.OpDesc,
 		ap.Op,
 		ap.SenderMAC,
 		ap.SenderIP,
@@ -56,16 +59,31 @@ func (ap *ARPPacket) String() string {
 	)
 }
 
+func (ap *ARPPacket) Summary() string {
+	var message string
+	switch ap.OpDesc {
+	case "request":
+		message = fmt.Sprintf("ARP Packet: (%s) Who has %s? Tell %s", ap.OpDesc, ap.TargetIP, ap.SenderIP)
+	case "reply":
+		message = fmt.Sprintf("ARP Packet: (%s) %s at %s", ap.OpDesc, ap.SenderIP, ap.SenderMAC)
+	default:
+		message = fmt.Sprintf("ARP Packet: (%s)", ap.OpDesc)
+	}
+	return message
+}
+
 // Parse parses the given ARP packet data into the ARPPacket struct.
 func (ap *ARPPacket) Parse(data []byte) error {
 	if len(data) < headerSizeARP {
 		return fmt.Errorf("minimum header size for ARP is %d bytes, got %d bytes", headerSizeARP, len(data))
 	}
 	ap.HardwareType = binary.BigEndian.Uint16(data[0:2])
 	ap.ProtocolType = binary.BigEndian.Uint16(data[2:4])
+	ap.ProtocolTypeDesc = ap.ptype()
 	ap.Hlen = data[4]
 	ap.Plen = data[5]
 	ap.Op = binary.BigEndian.Uint16(data[6:8])
+	ap.OpDesc = ap.op()
 	hoffset := 8 + ap.Hlen
 	ap.SenderMAC = net.HardwareAddr(data[8:hoffset])
 	poffset := hoffset + ap.Plen

layers/dns.go

@@ -20,16 +20,15 @@ type DNSMessage struct {
 }
 
 func (d *DNSMessage) String() string {
-	return fmt.Sprintf(`DNS Message:
-- Transaction ID: %#04x
+	return fmt.Sprintf(`%s- Transaction ID: %#04x
 - Flags: %#04x
 %s
 - Questions: %d
 - Answer RRs: %d
 - Authority RRs: %d
 - Additional RRs: %d
-%s
-`,
+%s`,
+		d.Summary(),
 		d.TransactionID,
 		d.Flags,
 		d.flags(),
@@ -41,6 +40,10 @@ func (d *DNSMessage) String() string {
 	)
 }
 
+func (d *DNSMessage) Summary() string {
+	return fmt.Sprint("DNS Message:")
+}
+
 // Parse parses the given byte data into a DNSMessage struct.
 func (d *DNSMessage) Parse(data []byte) error {
 	if len(data) < headerSizeDNS {

layers/ethernet.go

@@ -11,28 +11,33 @@ const headerSizeEthernet = 14
 
 // An Ethernet frame is a data link layer protocol data unit.
 type EthernetFrame struct {
-	DstMAC    net.HardwareAddr // MAC address of the destination device.
-	SrcMAC    net.HardwareAddr // MAC address of the source device.
-	EtherType uint16           // The protocol of the upper layer.
-	payload   []byte
+	DstMAC        net.HardwareAddr // MAC address of the destination device.
+	SrcMAC        net.HardwareAddr // MAC address of the source device.
+	EtherType     uint16           // The protocol of the upper layer.
+	EtherTypeDesc string           // Protocol description
+	payload       []byte
 }
 
 func (ef *EthernetFrame) String() string {
-	ethType, _ := ef.NextLayer()
-	return fmt.Sprintf(`Ethernet Frame:
+	return fmt.Sprintf(`%s
 - DstMAC: %s
 - SrcMAC: %s
 - EtherType: %s (%#04x)
 - Payload: %d bytes 
 %s`,
+		ef.Summary(),
 		ef.DstMAC,
 		ef.SrcMAC,
-		ethType,
+		ef.EtherTypeDesc,
 		ef.EtherType,
 		len(ef.payload),
 		hex.Dump(ef.payload))
 }
 
+func (ef *EthernetFrame) Summary() string {
+	return fmt.Sprintf("Ethernet Frame: Src: %s Dst: %s", ef.SrcMAC, ef.DstMAC)
+}
+
 // Parse parses the given byte data into an Ethernet frame.
 func (ef *EthernetFrame) Parse(data []byte) error {
 	if len(data) < headerSizeEthernet {
@@ -42,6 +47,7 @@ func (ef *EthernetFrame) Parse(data []byte) error {
 	ef.SrcMAC = net.HardwareAddr(data[6:12])
 	ef.EtherType = binary.BigEndian.Uint16(data[12:14])
 	ef.payload = data[headerSizeEthernet:]
+	ef.EtherTypeDesc, _ = ef.NextLayer()
 	return nil
 }
 

layers/ftp.go

@@ -7,9 +7,12 @@ type FTPMessage struct {
 }
 
 func (f *FTPMessage) String() string {
-	return fmt.Sprintf(`FTP Message:
-%s
-`, f.payload)
+	return fmt.Sprintf(`%s
+%s`, f.Summary(), f.payload)
+}
+
+func (f *FTPMessage) Summary() string {
+	return fmt.Sprint("FTP Message:")
 }
 
 func (f *FTPMessage) Parse(data []byte) error {

layers/http.go

@@ -9,9 +9,11 @@ type HTTPMessage struct {
 }
 
 func (h *HTTPMessage) String() string {
-	return fmt.Sprintf(`HTTP Message:
-%s
-`, h.payload)
+	return fmt.Sprintf(`%s
+%s`, h.Summary(), h.payload)
+}
+func (h *HTTPMessage) Summary() string {
+	return fmt.Sprint("HTTP Message:")
 }
 
 func (h *HTTPMessage) Parse(data []byte) error {

layers/icmp.go

@@ -10,31 +10,37 @@ const headerSizeICMP = 4
 
 // ICMP is part of the Internet protocol suite as defined in RFC 792.
 type ICMPSegment struct {
-	Type uint8 // ICMP type.
-	Code uint8 // ICMP subtype.
+	Type     uint8  // ICMP type.
+	TypeDesc string // ICMP type description.
+	Code     uint8  // ICMP subtype.
+	CodeDesc string // ICMP subtype description.
 	// Internet checksum (RFC 1071) for error checking, calculated from the ICMP header
 	// and data with value 0 substituted for this field.
 	Checksum uint16
 	Data     []byte // Contents vary based on the ICMP type and code.
 }
 
 func (i *ICMPSegment) String() string {
-	mtype, code := i.typecode()
-	return fmt.Sprintf(`ICMP Segment:
+	return fmt.Sprintf(`%s
 - Type: %d (%s)
 - Code: %d (%s)
 - Checksum: %#04x
 %s
 `,
+		i.Summary(),
 		i.Type,
-		mtype,
+		i.TypeDesc,
 		i.Code,
-		code,
+		i.CodeDesc,
 		i.Checksum,
 		i.data(),
 	)
 }
 
+func (i *ICMPSegment) Summary() string {
+	return fmt.Sprintf("ICMP Segment: %s (%s)", i.TypeDesc, i.CodeDesc)
+}
+
 // Parse parses the given byte data into an ICMP segment struct.
 func (i *ICMPSegment) Parse(data []byte) error {
 	if len(data) < headerSizeICMP {
@@ -56,6 +62,7 @@ func (i *ICMPSegment) Parse(data []byte) error {
 	if len(i.Data) < pLen {
 		return fmt.Errorf("minimum payload length for ICMP with type %d is %d bytes", i.Type, pLen)
 	}
+	i.TypeDesc, i.CodeDesc = i.typecode()
 	return nil
 }
 func (i *ICMPSegment) NextLayer() (string, []byte) {

layers/icmpv6.go

@@ -11,28 +11,34 @@ const headerSizeICMPv6 = 4
 // ICMPv6 is an integral part of IPv6 and performs error reporting and diagnostic functions.
 type ICMPv6Segment struct {
 	Type     uint8
+	TypeDesc string
 	Code     uint8
+	CodeDesc string
 	Checksum uint16
 	Data     []byte
 }
 
 func (i *ICMPv6Segment) String() string {
-	mtype, code := i.typecode()
-	return fmt.Sprintf(`ICMPv6 Segment:
+	return fmt.Sprintf(`%s
 - Type: %d (%s)
 - Code: %d (%s)
 - Checksum: %#04x
 %s
 `,
+		i.Summary(),
 		i.Type,
-		mtype,
+		i.TypeDesc,
 		i.Code,
-		code,
+		i.CodeDesc,
 		i.Checksum,
 		i.data(),
 	)
 }
 
+func (i *ICMPv6Segment) Summary() string {
+	return fmt.Sprintf("ICMPv6 Segment: %s (%s)", i.TypeDesc, i.CodeDesc)
+}
+
 // Parse parses the given byte data into an ICMPv6 segment struct.
 func (i *ICMPv6Segment) Parse(data []byte) error {
 	if len(data) < headerSizeICMPv6 {
@@ -58,6 +64,7 @@ func (i *ICMPv6Segment) Parse(data []byte) error {
 	if len(i.Data) < pLen {
 		return fmt.Errorf("minimum payload length for ICMPv6 with type %d is %d bytes", i.Type, pLen)
 	}
+	i.TypeDesc, i.CodeDesc = i.typecode()
 	return nil
 }