1 files changed, 111 insertions, 0 deletions
diff --git a/vendor/github.com/vishvananda/netlink/nl/seg6_linux.go b/vendor/github.com/vishvananda/netlink/nl/seg6_linux.go
new file mode 100644
index 000000000..b3425f6b0
--- /dev/null
+++ b/vendor/github.com/vishvananda/netlink/nl/seg6_linux.go
@@ -0,0 +1,111 @@
+package nl
+
+import (
+	"errors"
+	"fmt"
+	"net"
+)
+
+type IPv6SrHdr struct {
+	nextHdr      uint8
+	hdrLen       uint8
+	routingType  uint8
+	segmentsLeft uint8
+	firstSegment uint8
+	flags        uint8
+	reserved     uint16
+
+	Segments []net.IP
+}
+
+func (s1 *IPv6SrHdr) Equal(s2 IPv6SrHdr) bool {
+	if len(s1.Segments) != len(s2.Segments) {
+		return false
+	}
+	for i := range s1.Segments {
+		if s1.Segments[i].Equal(s2.Segments[i]) != true {
+			return false
+		}
+	}
+	return s1.nextHdr == s2.nextHdr &&
+		s1.hdrLen == s2.hdrLen &&
+		s1.routingType == s2.routingType &&
+		s1.segmentsLeft == s2.segmentsLeft &&
+		s1.firstSegment == s2.firstSegment &&
+		s1.flags == s2.flags
+	// reserved doesn't need to be identical.
+}
+
+// seg6 encap mode
+const (
+	SEG6_IPTUN_MODE_INLINE = iota
+	SEG6_IPTUN_MODE_ENCAP
+)
+
+// number of nested RTATTR
+// from include/uapi/linux/seg6_iptunnel.h
+const (
+	SEG6_IPTUNNEL_UNSPEC = iota
+	SEG6_IPTUNNEL_SRH
+	__SEG6_IPTUNNEL_MAX
+)
+const (
+	SEG6_IPTUNNEL_MAX = __SEG6_IPTUNNEL_MAX - 1
+)
+
+func EncodeSEG6Encap(mode int, segments []net.IP) ([]byte, error) {
+	nsegs := len(segments) // nsegs: number of segments
+	if nsegs == 0 {
+		return nil, errors.New("EncodeSEG6Encap: No Segment in srh")
+	}
+	b := make([]byte, 12, 12+len(segments)*16)
+	native := NativeEndian()
+	native.PutUint32(b, uint32(mode))
+	b[4] = 0                      // srh.nextHdr (0 when calling netlink)
+	b[5] = uint8(16 * nsegs >> 3) // srh.hdrLen (in 8-octets unit)
+	b[6] = IPV6_SRCRT_TYPE_4      // srh.routingType (assigned by IANA)
+	b[7] = uint8(nsegs - 1)       // srh.segmentsLeft
+	b[8] = uint8(nsegs - 1)       // srh.firstSegment
+	b[9] = 0                      // srh.flags (SR6_FLAG1_HMAC for srh_hmac)
+	// srh.reserved: Defined as "Tag" in draft-ietf-6man-segment-routing-header-07
+	native.PutUint16(b[10:], 0) // srh.reserved
+	for _, netIP := range segments {
+		b = append(b, netIP...) // srh.Segments
+	}
+	return b, nil
+}
+
+func DecodeSEG6Encap(buf []byte) (int, []net.IP, error) {
+	native := NativeEndian()
+	mode := int(native.Uint32(buf))
+	srh := IPv6SrHdr{
+		nextHdr:      buf[4],
+		hdrLen:       buf[5],
+		routingType:  buf[6],
+		segmentsLeft: buf[7],
+		firstSegment: buf[8],
+		flags:        buf[9],
+		reserved:     native.Uint16(buf[10:12]),
+	}
+	buf = buf[12:]
+	if len(buf)%16 != 0 {
+		err := fmt.Errorf("DecodeSEG6Encap: error parsing Segment List (buf len: %d)\n", len(buf))
+		return mode, nil, err
+	}
+	for len(buf) > 0 {
+		srh.Segments = append(srh.Segments, net.IP(buf[:16]))
+		buf = buf[16:]
+	}
+	return mode, srh.Segments, nil
+}
+
+// Helper functions
+func SEG6EncapModeString(mode int) string {
+	switch mode {
+	case SEG6_IPTUN_MODE_INLINE:
+		return "inline"
+	case SEG6_IPTUN_MODE_ENCAP:
+		return "encap"
+	}
+	return "unknown"
+}