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authorgVisor bot <gvisor-bot@google.com>2020-09-23 09:32:42 +0000
committergVisor bot <gvisor-bot@google.com>2020-09-23 09:32:42 +0000
commit0f688034971309cdab779c5030377eb88d4d5754 (patch)
treecf778633ff774ba3298d5a1f9e0e8a4abc667b7d /pkg/tcpip/header
parent8f530839ccfbea4d8bfe49891b44d408beed0126 (diff)
parent99decaadd6da0df2d8ec70ddea9d754c9d71a584 (diff)
Merge release-20200914.0-137-g99decaadd (automated)
Diffstat (limited to 'pkg/tcpip/header')
-rw-r--r--pkg/tcpip/header/icmpv4.go50
-rw-r--r--pkg/tcpip/header/icmpv6.go35
-rw-r--r--pkg/tcpip/header/ipv4.go5
3 files changed, 81 insertions, 9 deletions
diff --git a/pkg/tcpip/header/icmpv4.go b/pkg/tcpip/header/icmpv4.go
index be03fb086..c00bcadfb 100644
--- a/pkg/tcpip/header/icmpv4.go
+++ b/pkg/tcpip/header/icmpv4.go
@@ -31,6 +31,27 @@ const (
// ICMPv4MinimumSize is the minimum size of a valid ICMP packet.
ICMPv4MinimumSize = 8
+ // ICMPv4MinimumErrorPayloadSize Is the smallest number of bytes of an
+ // errant packet's transport layer that an ICMP error type packet should
+ // attempt to send as per RFC 792 (see each type) and RFC 1122
+ // section 3.2.2 which states:
+ // Every ICMP error message includes the Internet header and at
+ // least the first 8 data octets of the datagram that triggered
+ // the error; more than 8 octets MAY be sent; this header and data
+ // MUST be unchanged from the received datagram.
+ //
+ // RFC 792 shows:
+ // 0 1 2 3
+ // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ // | Type | Code | Checksum |
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ // | unused |
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ // | Internet Header + 64 bits of Original Data Datagram |
+ // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ ICMPv4MinimumErrorPayloadSize = 8
+
// ICMPv4ProtocolNumber is the ICMP transport protocol number.
ICMPv4ProtocolNumber tcpip.TransportProtocolNumber = 1
@@ -39,15 +60,19 @@ const (
icmpv4ChecksumOffset = 2
// icmpv4MTUOffset is the offset of the MTU field
- // in a ICMPv4FragmentationNeeded message.
+ // in an ICMPv4FragmentationNeeded message.
icmpv4MTUOffset = 6
// icmpv4IdentOffset is the offset of the ident field
- // in a ICMPv4EchoRequest/Reply message.
+ // in an ICMPv4EchoRequest/Reply message.
icmpv4IdentOffset = 4
+ // icmpv4PointerOffset is the offset of the pointer field
+ // in an ICMPv4ParamProblem message.
+ icmpv4PointerOffset = 4
+
// icmpv4SequenceOffset is the offset of the sequence field
- // in a ICMPv4EchoRequest/Reply message.
+ // in an ICMPv4EchoRequest/Reply message.
icmpv4SequenceOffset = 6
)
@@ -72,15 +97,23 @@ const (
ICMPv4InfoReply ICMPv4Type = 16
)
+// ICMP codes for ICMPv4 Time Exceeded messages as defined in RFC 792.
+const (
+ ICMPv4TTLExceeded ICMPv4Code = 0
+)
+
// ICMP codes for ICMPv4 Destination Unreachable messages as defined in RFC 792.
const (
- ICMPv4TTLExceeded ICMPv4Code = 0
+ ICMPv4NetUnreachable ICMPv4Code = 0
ICMPv4HostUnreachable ICMPv4Code = 1
ICMPv4ProtoUnreachable ICMPv4Code = 2
ICMPv4PortUnreachable ICMPv4Code = 3
ICMPv4FragmentationNeeded ICMPv4Code = 4
)
+// ICMPv4UnusedCode is a code to use in ICMP messages where no code is needed.
+const ICMPv4UnusedCode ICMPv4Code = 0
+
// Type is the ICMP type field.
func (b ICMPv4) Type() ICMPv4Type { return ICMPv4Type(b[0]) }
@@ -93,6 +126,15 @@ func (b ICMPv4) Code() ICMPv4Code { return ICMPv4Code(b[1]) }
// SetCode sets the ICMP code field.
func (b ICMPv4) SetCode(c ICMPv4Code) { b[1] = byte(c) }
+// SetPointer sets the pointer field in a Parameter error packet.
+// This is the first byte of the type specific data field.
+func (b ICMPv4) SetPointer(c byte) { b[icmpv4PointerOffset] = c }
+
+// SetTypeSpecific sets the full 32 bit type specific data field.
+func (b ICMPv4) SetTypeSpecific(val uint32) {
+ binary.BigEndian.PutUint32(b[icmpv4PointerOffset:], val)
+}
+
// Checksum is the ICMP checksum field.
func (b ICMPv4) Checksum() uint16 {
return binary.BigEndian.Uint16(b[icmpv4ChecksumOffset:])
diff --git a/pkg/tcpip/header/icmpv6.go b/pkg/tcpip/header/icmpv6.go
index 20b01d8f4..4eb5abd79 100644
--- a/pkg/tcpip/header/icmpv6.go
+++ b/pkg/tcpip/header/icmpv6.go
@@ -54,9 +54,17 @@ const (
// address.
ICMPv6NeighborAdvertSize = ICMPv6HeaderSize + NDPNAMinimumSize + NDPLinkLayerAddressSize
- // ICMPv6EchoMinimumSize is the minimum size of a valid ICMP echo packet.
+ // ICMPv6EchoMinimumSize is the minimum size of a valid echo packet.
ICMPv6EchoMinimumSize = 8
+ // ICMPv6ErrorHeaderSize is the size of an ICMP error packet header,
+ // as per RFC 4443, Apendix A, item 4 and the errata.
+ // ... all ICMP error messages shall have exactly
+ // 32 bits of type-specific data, so that receivers can reliably find
+ // the embedded invoking packet even when they don't recognize the
+ // ICMP message Type.
+ ICMPv6ErrorHeaderSize = 8
+
// ICMPv6DstUnreachableMinimumSize is the minimum size of a valid ICMP
// destination unreachable packet.
ICMPv6DstUnreachableMinimumSize = ICMPv6MinimumSize
@@ -69,6 +77,10 @@ const (
// in an ICMPv6 message.
icmpv6ChecksumOffset = 2
+ // icmpv6PointerOffset is the offset of the pointer
+ // in an ICMPv6 Parameter problem message.
+ icmpv6PointerOffset = 4
+
// icmpv6MTUOffset is the offset of the MTU field in an ICMPv6
// PacketTooBig message.
icmpv6MTUOffset = 4
@@ -89,9 +101,10 @@ const (
NDPHopLimit = 255
)
-// ICMPv6Type is the ICMP type field described in RFC 4443 and friends.
+// ICMPv6Type is the ICMP type field described in RFC 4443.
type ICMPv6Type byte
+// Values for use in the Type field of ICMPv6 packet from RFC 4433.
const (
ICMPv6DstUnreachable ICMPv6Type = 1
ICMPv6PacketTooBig ICMPv6Type = 2
@@ -109,7 +122,18 @@ const (
ICMPv6RedirectMsg ICMPv6Type = 137
)
-// ICMPv6Code is the ICMP code field described in RFC 4443.
+// IsErrorType returns true if the receiver is an ICMP error type.
+func (typ ICMPv6Type) IsErrorType() bool {
+ // Per RFC 4443 section 2.1:
+ // ICMPv6 messages are grouped into two classes: error messages and
+ // informational messages. Error messages are identified as such by a
+ // zero in the high-order bit of their message Type field values. Thus,
+ // error messages have message types from 0 to 127; informational
+ // messages have message types from 128 to 255.
+ return typ&0x80 == 0
+}
+
+// ICMPv6Code is the ICMP Code field described in RFC 4443.
type ICMPv6Code byte
// ICMP codes used with Destination Unreachable (Type 1). As per RFC 4443
@@ -153,6 +177,11 @@ func (b ICMPv6) Code() ICMPv6Code { return ICMPv6Code(b[1]) }
// SetCode sets the ICMP code field.
func (b ICMPv6) SetCode(c ICMPv6Code) { b[1] = byte(c) }
+// SetTypeSpecific sets the full 32 bit type specific data field.
+func (b ICMPv6) SetTypeSpecific(val uint32) {
+ binary.BigEndian.PutUint32(b[icmpv6PointerOffset:], val)
+}
+
// Checksum is the ICMP checksum field.
func (b ICMPv6) Checksum() uint16 {
return binary.BigEndian.Uint16(b[icmpv6ChecksumOffset:])
diff --git a/pkg/tcpip/header/ipv4.go b/pkg/tcpip/header/ipv4.go
index e8816c3f4..b07d9991d 100644
--- a/pkg/tcpip/header/ipv4.go
+++ b/pkg/tcpip/header/ipv4.go
@@ -80,7 +80,8 @@ type IPv4Fields struct {
type IPv4 []byte
const (
- // IPv4MinimumSize is the minimum size of a valid IPv4 packet.
+ // IPv4MinimumSize is the minimum size of a valid IPv4 packet;
+ // i.e. a packet header with no options.
IPv4MinimumSize = 20
// IPv4MaximumHeaderSize is the maximum size of an IPv4 header. Given
@@ -327,7 +328,7 @@ func IsV4MulticastAddress(addr tcpip.Address) bool {
}
// IsV4LoopbackAddress determines if the provided address is an IPv4 loopback
-// address (belongs to 127.0.0.1/8 subnet).
+// address (belongs to 127.0.0.0/8 subnet). See RFC 1122 section 3.2.1.3.
func IsV4LoopbackAddress(addr tcpip.Address) bool {
if len(addr) != IPv4AddressSize {
return false