diff options
Diffstat (limited to 'pkg/tcpip/header/icmpv6.go')
| -rw-r--r-- | pkg/tcpip/header/icmpv6.go | 86 |
1 files changed, 72 insertions, 14 deletions
diff --git a/pkg/tcpip/header/icmpv6.go b/pkg/tcpip/header/icmpv6.go index a13b4b809..6be31beeb 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 @@ -89,10 +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 -// Typical values of ICMPv6Type defined in RFC 4443. +// Values for use in the Type field of ICMPv6 packet from RFC 4433. const ( ICMPv6DstUnreachable ICMPv6Type = 1 ICMPv6PacketTooBig ICMPv6Type = 2 @@ -110,18 +122,54 @@ const ( ICMPv6RedirectMsg ICMPv6Type = 137 ) -// Values for ICMP destination unreachable code as defined in RFC 4443 section -// 3.1. +// 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 +// section 3.1. +const ( + ICMPv6NetworkUnreachable ICMPv6Code = 0 + ICMPv6Prohibited ICMPv6Code = 1 + ICMPv6BeyondScope ICMPv6Code = 2 + ICMPv6AddressUnreachable ICMPv6Code = 3 + ICMPv6PortUnreachable ICMPv6Code = 4 + ICMPv6Policy ICMPv6Code = 5 + ICMPv6RejectRoute ICMPv6Code = 6 +) + +// ICMP codes used with Time Exceeded (Type 3). As per RFC 4443 section 3.3. +const ( + ICMPv6HopLimitExceeded ICMPv6Code = 0 + ICMPv6ReassemblyTimeout ICMPv6Code = 1 +) + +// ICMP codes used with Parameter Problem (Type 4). As per RFC 4443 section 3.4. const ( - ICMPv6NetworkUnreachable = 0 - ICMPv6Prohibited = 1 - ICMPv6BeyondScope = 2 - ICMPv6AddressUnreachable = 3 - ICMPv6PortUnreachable = 4 - ICMPv6Policy = 5 - ICMPv6RejectRoute = 6 + // ICMPv6ErroneousHeader indicates an erroneous header field was encountered. + ICMPv6ErroneousHeader ICMPv6Code = 0 + + // ICMPv6UnknownHeader indicates an unrecognized Next Header type encountered. + ICMPv6UnknownHeader ICMPv6Code = 1 + + // ICMPv6UnknownOption indicates an unrecognized IPv6 option was encountered. + ICMPv6UnknownOption ICMPv6Code = 2 ) +// ICMPv6UnusedCode is the code value used with ICMPv6 messages which don't use +// the code field. (Types not mentioned above.) +const ICMPv6UnusedCode ICMPv6Code = 0 + // Type is the ICMP type field. func (b ICMPv6) Type() ICMPv6Type { return ICMPv6Type(b[0]) } @@ -129,10 +177,20 @@ func (b ICMPv6) Type() ICMPv6Type { return ICMPv6Type(b[0]) } func (b ICMPv6) SetType(t ICMPv6Type) { b[0] = byte(t) } // Code is the ICMP code field. Its meaning depends on the value of Type. -func (b ICMPv6) Code() byte { return b[1] } +func (b ICMPv6) Code() ICMPv6Code { return ICMPv6Code(b[1]) } // SetCode sets the ICMP code field. -func (b ICMPv6) SetCode(c byte) { b[1] = c } +func (b ICMPv6) SetCode(c ICMPv6Code) { b[1] = byte(c) } + +// TypeSpecific returns the type specific data field. +func (b ICMPv6) TypeSpecific() uint32 { + return binary.BigEndian.Uint32(b[icmpv6PointerOffset:]) +} + +// SetTypeSpecific sets the 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 { |