/
constants.go
147 lines (116 loc) · 3.53 KB
/
constants.go
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package packet
const (
// minIPPacketLen is the min ip packet size for TCP packet
minTCPIPPacketLen = 40
// minIPPacketLen is the min ip packet size for UDP packet
minUDPIPPacketLen = 28
// minIPHdrSize
minIPHdrSize = 20
minIPHdrWords = (minIPHdrSize / 4)
)
// IP Header field position constants
const (
// ipHdrLenPos is location of IP (entire packet) length
ipHdrLenPos = 0
// ipLengthPos is location of IP (entire packet) length
ipLengthPos = 2
// ipIDPos is location of IP Identifier
IPIDPos = 4
// ipProtoPos is the location of the IP Protocol
ipProtoPos = 9
// ipChecksumPos is location of IP checksum
ipChecksumPos = 10
// ipSourceAddrPos is location of source IP address
ipSourceAddrPos = 12
// ipDestAddrPos is location of destination IP address
ipDestAddrPos = 16
)
// IP Protocol numbers
const (
// IPProtocolTCP defines the constant for UDP protocol number
IPProtocolTCP = 6
// IPProtocolUDP defines the constant for UDP protocol number
IPProtocolUDP = 17
)
// IP Header masks
const (
ipHdrLenMask = 0xF
)
// TCP Header field position constants
const (
// tcpSourcePortPos is the location of source port
tcpSourcePortPos = 20
// tcpDestPortPos is the location of destination port
tcpDestPortPos = 22
// tcpSeqPos is the location of seq
tcpSeqPos = 24
// tcpAckPos is the location of seq
tcpAckPos = 28
// tcpDataOffsetPos is the location of the TCP data offset
tcpDataOffsetPos = 32
//tcpFlagsOfsetPos is the location of the TCP flags
tcpFlagsOffsetPos = 33
// TCPChecksumPos is the location of TCP checksum
TCPChecksumPos = 36
)
// TCP Header masks
const (
// tcpDataOffsetMask is a mask for TCP data offset field
tcpDataOffsetMask = 0xF0
// TCPSynMask is a mask for the TCP Syn flags
TCPSynMask = 0x2
// TCPSynAckMask mask idenitifies a TCP SYN-ACK packet
TCPSynAckMask = 0x12
// TCPRstMask mask that identifies RST packets
TCPRstMask = 0x4
// TCPAckMask mask that identifies ACK packets
TCPAckMask = 0x10
// TCPFinMask mask that identifies FIN packets
TCPFinMask = 0x1
// TCPPshMask = 0x8 mask that identifies PSH packets
TCPPshMask = 0x8
)
// TCP Options Related constants
const (
// TCPAuthenticationOption is the option number will be using
TCPAuthenticationOption = uint8(34)
// TCPMssOption is the type for MSS option
TCPMssOption = uint8(2)
// TCPMssOptionLen is the type for MSS option
TCPMssOptionLen = uint8(4)
)
// UDP related constants.
const (
// UDPLengthPos is the location of UDP length
UDPLengthPos = 24
// UDPChecksumPos is the location of UDP checksum
UDPChecksumPos = 26
// UDPDataPos is the location of UDP data
UDPDataPos = 28
// UDPBeginPos is the location of UDP Header
UDPBeginPos = 20
// UDPSynMask is a mask for the UDP Syn flags
UDPSynMask = 0x10
// UDPSynAckMask mask idenitifies a UDP SYN-ACK packet
UDPSynAckMask = 0x20
// UDPAckMask mask that identifies ACK packets.
UDPAckMask = 0x30
// UDPFinAckMask mask that identifies the FinAck packets
UDPFinAckMask = 0x40
// UDPPacketMask identifies type of UDP packet.
UDPPacketMask = 0x70
)
const (
// UDPAuthMarker is 18 byte Aporeto signature for UDP
UDPAuthMarker = "n30njxq7bmiwr6dtxq"
// UDPAuthMarkerLen is the length of UDP marker.
UDPAuthMarkerLen = 18
// UDPSignatureLen is the length of signature on UDP control packet.
UDPSignatureLen = 20
// UDPAuthMarkerOffset is the beginning of UDPAuthMarker
UDPAuthMarkerOffset = 30
// UDPSignatureEnd is the end of UDPSignature.
UDPSignatureEnd = UDPDataPos + UDPSignatureLen
// UDPJwtTokenOffset is beginning of Jwt Token.
UDPJwtTokenOffset = 48
)