summaryrefslogtreecommitdiff
path: root/vendor/golang.org/x/net/icmp/ipv4.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/golang.org/x/net/icmp/ipv4.go')
-rw-r--r--vendor/golang.org/x/net/icmp/ipv4.go61
1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/icmp/ipv4.go b/vendor/golang.org/x/net/icmp/ipv4.go
new file mode 100644
index 0000000..ffc66ed
--- /dev/null
+++ b/vendor/golang.org/x/net/icmp/ipv4.go
@@ -0,0 +1,61 @@
+// Copyright 2014 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 icmp
+
+import (
+ "encoding/binary"
+ "net"
+ "runtime"
+
+ "golang.org/x/net/internal/socket"
+ "golang.org/x/net/ipv4"
+)
+
+// freebsdVersion is set in sys_freebsd.go.
+// See http://www.freebsd.org/doc/en/books/porters-handbook/freebsd-versions.html.
+var freebsdVersion uint32
+
+// ParseIPv4Header parses b as an IPv4 header of ICMP error message
+// invoking packet, which is contained in ICMP error message.
+func ParseIPv4Header(b []byte) (*ipv4.Header, error) {
+ if len(b) < ipv4.HeaderLen {
+ return nil, errHeaderTooShort
+ }
+ hdrlen := int(b[0]&0x0f) << 2
+ if hdrlen > len(b) {
+ return nil, errBufferTooShort
+ }
+ h := &ipv4.Header{
+ Version: int(b[0] >> 4),
+ Len: hdrlen,
+ TOS: int(b[1]),
+ ID: int(binary.BigEndian.Uint16(b[4:6])),
+ FragOff: int(binary.BigEndian.Uint16(b[6:8])),
+ TTL: int(b[8]),
+ Protocol: int(b[9]),
+ Checksum: int(binary.BigEndian.Uint16(b[10:12])),
+ Src: net.IPv4(b[12], b[13], b[14], b[15]),
+ Dst: net.IPv4(b[16], b[17], b[18], b[19]),
+ }
+ switch runtime.GOOS {
+ case "darwin":
+ h.TotalLen = int(socket.NativeEndian.Uint16(b[2:4]))
+ case "freebsd":
+ if freebsdVersion >= 1000000 {
+ h.TotalLen = int(binary.BigEndian.Uint16(b[2:4]))
+ } else {
+ h.TotalLen = int(socket.NativeEndian.Uint16(b[2:4]))
+ }
+ default:
+ h.TotalLen = int(binary.BigEndian.Uint16(b[2:4]))
+ }
+ h.Flags = ipv4.HeaderFlags(h.FragOff&0xe000) >> 13
+ h.FragOff = h.FragOff & 0x1fff
+ if hdrlen-ipv4.HeaderLen > 0 {
+ h.Options = make([]byte, hdrlen-ipv4.HeaderLen)
+ copy(h.Options, b[ipv4.HeaderLen:])
+ }
+ return h, nil
+}