diff options
Diffstat (limited to 'pkg/tcpip/header/ipv6.go')
| -rw-r--r-- | pkg/tcpip/header/ipv6.go | 53 |
1 files changed, 23 insertions, 30 deletions
diff --git a/pkg/tcpip/header/ipv6.go b/pkg/tcpip/header/ipv6.go index 55d09355a..5580d6a78 100644 --- a/pkg/tcpip/header/ipv6.go +++ b/pkg/tcpip/header/ipv6.go @@ -18,7 +18,6 @@ import ( "crypto/sha256" "encoding/binary" "fmt" - "strings" "gvisor.dev/gvisor/pkg/tcpip" ) @@ -48,11 +47,13 @@ type IPv6Fields struct { // FlowLabel is the "flow label" field of an IPv6 packet. FlowLabel uint32 - // PayloadLength is the "payload length" field of an IPv6 packet. + // PayloadLength is the "payload length" field of an IPv6 packet, including + // the length of all extension headers. PayloadLength uint16 - // NextHeader is the "next header" field of an IPv6 packet. - NextHeader uint8 + // TransportProtocol is the transport layer protocol number. Serialized in the + // last "next header" field of the IPv6 header + extension headers. + TransportProtocol tcpip.TransportProtocolNumber // HopLimit is the "Hop Limit" field of an IPv6 packet. HopLimit uint8 @@ -62,6 +63,9 @@ type IPv6Fields struct { // DstAddr is the "destination ip address" of an IPv6 packet. DstAddr tcpip.Address + + // ExtensionHeaders are the extension headers following the IPv6 header. + ExtensionHeaders IPv6ExtHdrSerializer } // IPv6 represents an ipv6 header stored in a byte array. @@ -148,13 +152,17 @@ const ( // IPv6EmptySubnet is the empty IPv6 subnet. It may also be known as the // catch-all or wildcard subnet. That is, all IPv6 addresses are considered to // be contained within this subnet. -var IPv6EmptySubnet = func() tcpip.Subnet { - subnet, err := tcpip.NewSubnet(IPv6Any, tcpip.AddressMask(IPv6Any)) - if err != nil { - panic(err) - } - return subnet -}() +var IPv6EmptySubnet = tcpip.AddressWithPrefix{ + Address: IPv6Any, + PrefixLen: 0, +}.Subnet() + +// IPv4MappedIPv6Subnet is the prefix for an IPv4 mapped IPv6 address as defined +// by RFC 4291 section 2.5.5. +var IPv4MappedIPv6Subnet = tcpip.AddressWithPrefix{ + Address: "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\x00\x00\x00\x00", + PrefixLen: 96, +}.Subnet() // IPv6LinkLocalPrefix is the prefix for IPv6 link-local addresses, as defined // by RFC 4291 section 2.5.6. @@ -253,12 +261,14 @@ func (IPv6) SetChecksum(uint16) { // Encode encodes all the fields of the ipv6 header. func (b IPv6) Encode(i *IPv6Fields) { + extHdr := b[IPv6MinimumSize:] b.SetTOS(i.TrafficClass, i.FlowLabel) b.SetPayloadLength(i.PayloadLength) - b[IPv6NextHeaderOffset] = i.NextHeader b[hopLimit] = i.HopLimit b.SetSourceAddress(i.SrcAddr) b.SetDestinationAddress(i.DstAddr) + nextHeader, _ := i.ExtensionHeaders.Serialize(i.TransportProtocol, extHdr) + b[IPv6NextHeaderOffset] = nextHeader } // IsValid performs basic validation on the packet. @@ -286,7 +296,7 @@ func IsV4MappedAddress(addr tcpip.Address) bool { return false } - return strings.HasPrefix(string(addr), "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff") + return IPv4MappedIPv6Subnet.Contains(addr) } // IsV6MulticastAddress determines if the provided address is an IPv6 @@ -392,17 +402,6 @@ func IsV6LinkLocalMulticastAddress(addr tcpip.Address) bool { return IsV6MulticastAddress(addr) && addr[ipv6MulticastAddressScopeByteIdx]&ipv6MulticastAddressScopeMask == ipv6LinkLocalMulticastScope } -// IsV6UniqueLocalAddress determines if the provided address is an IPv6 -// unique-local address (within the prefix FC00::/7). -func IsV6UniqueLocalAddress(addr tcpip.Address) bool { - if len(addr) != IPv6AddressSize { - return false - } - // According to RFC 4193 section 3.1, a unique local address has the prefix - // FC00::/7. - return (addr[0] & 0xfe) == 0xfc -} - // AppendOpaqueInterfaceIdentifier appends a 64 bit opaque interface identifier // (IID) to buf as outlined by RFC 7217 and returns the extended buffer. // @@ -449,9 +448,6 @@ const ( // LinkLocalScope indicates a link-local address. LinkLocalScope IPv6AddressScope = iota - // UniqueLocalScope indicates a unique-local address. - UniqueLocalScope - // GlobalScope indicates a global address. GlobalScope ) @@ -469,9 +465,6 @@ func ScopeForIPv6Address(addr tcpip.Address) (IPv6AddressScope, *tcpip.Error) { case IsV6LinkLocalAddress(addr): return LinkLocalScope, nil - case IsV6UniqueLocalAddress(addr): - return UniqueLocalScope, nil - default: return GlobalScope, nil } |