import (
"bytes"
- "errors"
"fmt"
"os"
"reflect"
return b[hdrlen:]
}
-const (
- icmpv4EchoRequest = 8
- icmpv4EchoReply = 0
- icmpv6EchoRequest = 128
- icmpv6EchoReply = 129
-)
-
-// icmpMessage represents an ICMP message.
-type icmpMessage struct {
- Type int // type
- Code int // code
- Checksum int // checksum
- Body icmpMessageBody // body
-}
-
-// icmpMessageBody represents an ICMP message body.
-type icmpMessageBody interface {
- Len() int
- Marshal() ([]byte, error)
-}
-
-// Marshal returns the binary enconding of the ICMP echo request or
-// reply message m.
-func (m *icmpMessage) Marshal() ([]byte, error) {
- b := []byte{byte(m.Type), byte(m.Code), 0, 0}
- if m.Body != nil && m.Body.Len() != 0 {
- mb, err := m.Body.Marshal()
- if err != nil {
- return nil, err
- }
- b = append(b, mb...)
- }
- switch m.Type {
- case icmpv6EchoRequest, icmpv6EchoReply:
- return b, nil
- }
- csumcv := len(b) - 1 // checksum coverage
- s := uint32(0)
- for i := 0; i < csumcv; i += 2 {
- s += uint32(b[i+1])<<8 | uint32(b[i])
- }
- if csumcv&1 == 0 {
- s += uint32(b[csumcv])
- }
- s = s>>16 + s&0xffff
- s = s + s>>16
- // Place checksum back in header; using ^= avoids the
- // assumption the checksum bytes are zero.
- b[2] ^= byte(^s)
- b[3] ^= byte(^s >> 8)
- return b, nil
-}
-
-// parseICMPMessage parses b as an ICMP message.
-func parseICMPMessage(b []byte) (*icmpMessage, error) {
- msglen := len(b)
- if msglen < 4 {
- return nil, errors.New("message too short")
- }
- m := &icmpMessage{Type: int(b[0]), Code: int(b[1]), Checksum: int(b[2])<<8 | int(b[3])}
- if msglen > 4 {
- var err error
- switch m.Type {
- case icmpv4EchoRequest, icmpv4EchoReply, icmpv6EchoRequest, icmpv6EchoReply:
- m.Body, err = parseICMPEcho(b[4:])
- if err != nil {
- return nil, err
- }
- }
- }
- return m, nil
-}
-
-// imcpEcho represenets an ICMP echo request or reply message body.
-type icmpEcho struct {
- ID int // identifier
- Seq int // sequence number
- Data []byte // data
-}
-
-func (p *icmpEcho) Len() int {
- if p == nil {
- return 0
- }
- return 4 + len(p.Data)
-}
-
-// Marshal returns the binary enconding of the ICMP echo request or
-// reply message body p.
-func (p *icmpEcho) Marshal() ([]byte, error) {
- b := make([]byte, 4+len(p.Data))
- b[0], b[1] = byte(p.ID>>8), byte(p.ID)
- b[2], b[3] = byte(p.Seq>>8), byte(p.Seq)
- copy(b[4:], p.Data)
- return b, nil
-}
-
-// parseICMPEcho parses b as an ICMP echo request or reply message
-// body.
-func parseICMPEcho(b []byte) (*icmpEcho, error) {
- bodylen := len(b)
- p := &icmpEcho{ID: int(b[0])<<8 | int(b[1]), Seq: int(b[2])<<8 | int(b[3])}
- if bodylen > 4 {
- p.Data = make([]byte, bodylen-4)
- copy(p.Data, b[4:])
- }
- return p, nil
-}
-
var ipConnLocalNameTests = []struct {
net string
laddr *IPAddr
--- /dev/null
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import "errors"
+
+const (
+ icmpv4EchoRequest = 8
+ icmpv4EchoReply = 0
+ icmpv6EchoRequest = 128
+ icmpv6EchoReply = 129
+)
+
+// icmpMessage represents an ICMP message.
+type icmpMessage struct {
+ Type int // type
+ Code int // code
+ Checksum int // checksum
+ Body icmpMessageBody // body
+}
+
+// icmpMessageBody represents an ICMP message body.
+type icmpMessageBody interface {
+ Len() int
+ Marshal() ([]byte, error)
+}
+
+// Marshal returns the binary enconding of the ICMP echo request or
+// reply message m.
+func (m *icmpMessage) Marshal() ([]byte, error) {
+ b := []byte{byte(m.Type), byte(m.Code), 0, 0}
+ if m.Body != nil && m.Body.Len() != 0 {
+ mb, err := m.Body.Marshal()
+ if err != nil {
+ return nil, err
+ }
+ b = append(b, mb...)
+ }
+ switch m.Type {
+ case icmpv6EchoRequest, icmpv6EchoReply:
+ return b, nil
+ }
+ csumcv := len(b) - 1 // checksum coverage
+ s := uint32(0)
+ for i := 0; i < csumcv; i += 2 {
+ s += uint32(b[i+1])<<8 | uint32(b[i])
+ }
+ if csumcv&1 == 0 {
+ s += uint32(b[csumcv])
+ }
+ s = s>>16 + s&0xffff
+ s = s + s>>16
+ // Place checksum back in header; using ^= avoids the
+ // assumption the checksum bytes are zero.
+ b[2] ^= byte(^s)
+ b[3] ^= byte(^s >> 8)
+ return b, nil
+}
+
+// parseICMPMessage parses b as an ICMP message.
+func parseICMPMessage(b []byte) (*icmpMessage, error) {
+ msglen := len(b)
+ if msglen < 4 {
+ return nil, errors.New("message too short")
+ }
+ m := &icmpMessage{Type: int(b[0]), Code: int(b[1]), Checksum: int(b[2])<<8 | int(b[3])}
+ if msglen > 4 {
+ var err error
+ switch m.Type {
+ case icmpv4EchoRequest, icmpv4EchoReply, icmpv6EchoRequest, icmpv6EchoReply:
+ m.Body, err = parseICMPEcho(b[4:])
+ if err != nil {
+ return nil, err
+ }
+ }
+ }
+ return m, nil
+}
+
+// imcpEcho represenets an ICMP echo request or reply message body.
+type icmpEcho struct {
+ ID int // identifier
+ Seq int // sequence number
+ Data []byte // data
+}
+
+func (p *icmpEcho) Len() int {
+ if p == nil {
+ return 0
+ }
+ return 4 + len(p.Data)
+}
+
+// Marshal returns the binary enconding of the ICMP echo request or
+// reply message body p.
+func (p *icmpEcho) Marshal() ([]byte, error) {
+ b := make([]byte, 4+len(p.Data))
+ b[0], b[1] = byte(p.ID>>8), byte(p.ID)
+ b[2], b[3] = byte(p.Seq>>8), byte(p.Seq)
+ copy(b[4:], p.Data)
+ return b, nil
+}
+
+// parseICMPEcho parses b as an ICMP echo request or reply message
+// body.
+func parseICMPEcho(b []byte) (*icmpEcho, error) {
+ bodylen := len(b)
+ p := &icmpEcho{ID: int(b[0])<<8 | int(b[1]), Seq: int(b[2])<<8 | int(b[3])}
+ if bodylen > 4 {
+ p.Data = make([]byte, bodylen-4)
+ copy(p.Data, b[4:])
+ }
+ return p, nil
+}