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-rw-r--r--vendor/golang.org/x/net/icmp/mpls.go77
1 files changed, 77 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/icmp/mpls.go b/vendor/golang.org/x/net/icmp/mpls.go
new file mode 100644
index 0000000..f9f4841
--- /dev/null
+++ b/vendor/golang.org/x/net/icmp/mpls.go
@@ -0,0 +1,77 @@
+// Copyright 2015 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"
+
+// MPLSLabel represents an MPLS label stack entry.
+type MPLSLabel struct {
+ Label int // label value
+ TC int // traffic class; formerly experimental use
+ S bool // bottom of stack
+ TTL int // time to live
+}
+
+const (
+ classMPLSLabelStack = 1
+ typeIncomingMPLSLabelStack = 1
+)
+
+// MPLSLabelStack represents an MPLS label stack.
+type MPLSLabelStack struct {
+ Class int // extension object class number
+ Type int // extension object sub-type
+ Labels []MPLSLabel
+}
+
+// Len implements the Len method of Extension interface.
+func (ls *MPLSLabelStack) Len(proto int) int {
+ return 4 + (4 * len(ls.Labels))
+}
+
+// Marshal implements the Marshal method of Extension interface.
+func (ls *MPLSLabelStack) Marshal(proto int) ([]byte, error) {
+ b := make([]byte, ls.Len(proto))
+ if err := ls.marshal(proto, b); err != nil {
+ return nil, err
+ }
+ return b, nil
+}
+
+func (ls *MPLSLabelStack) marshal(proto int, b []byte) error {
+ l := ls.Len(proto)
+ binary.BigEndian.PutUint16(b[:2], uint16(l))
+ b[2], b[3] = classMPLSLabelStack, typeIncomingMPLSLabelStack
+ off := 4
+ for _, ll := range ls.Labels {
+ b[off], b[off+1], b[off+2] = byte(ll.Label>>12), byte(ll.Label>>4&0xff), byte(ll.Label<<4&0xf0)
+ b[off+2] |= byte(ll.TC << 1 & 0x0e)
+ if ll.S {
+ b[off+2] |= 0x1
+ }
+ b[off+3] = byte(ll.TTL)
+ off += 4
+ }
+ return nil
+}
+
+func parseMPLSLabelStack(b []byte) (Extension, error) {
+ ls := &MPLSLabelStack{
+ Class: int(b[2]),
+ Type: int(b[3]),
+ }
+ for b = b[4:]; len(b) >= 4; b = b[4:] {
+ ll := MPLSLabel{
+ Label: int(b[0])<<12 | int(b[1])<<4 | int(b[2])>>4,
+ TC: int(b[2]&0x0e) >> 1,
+ TTL: int(b[3]),
+ }
+ if b[2]&0x1 != 0 {
+ ll.S = true
+ }
+ ls.Labels = append(ls.Labels, ll)
+ }
+ return ls, nil
+}