Provides access to fields in a TCP header.
| Instance Variables | |
| src_port | tcp.src_port -> anInteger | 
| Source Port (16-bit) | |
| dst_port | tcp.dst_port -> anInteger | 
| Destination Port (16-bit) | |
| seq_nbr | tcp.seq_nbr -> anInteger | 
| Sequence Number (32-bit) | |
| ack_nbr | tcp.ack_nbr -> anInteger | 
| Acknowledgement Number (32-bit) | |
| doff | tcp.doff -> anInteger | 
| Data Offset (4-byte units); header is doff*4 bytes long | |
| flags | tcp.flags -> anInteger | 
| 12-bit integer, with the 6 flags below in its 6 low-order bits | |
| urg_flag | tcp.urg_flag -> true or false | 
| True if 'Urgent' flag is 1 | |
| ack_flag | tcp.ack_flag -> true or false | 
| True if 'Acknowledge' flag is 1 | |
| psh_flag | tcp.psh_flag -> true or false | 
| True if 'Push' flag is 1 | |
| rst_flag | tcp.rst_flag -> true or false | 
| True if 'Reset'' flag is 1 | |
| syn_flag | tcp.syn_flag -> true or false | 
| True if 'Synchronise' flag is 1 | |
| fin_flag | tcp.fin_flag -> true or false | 
| True if 'Finish' flag is 1 | |
| window | tcp.window-> anInteger | 
| Receive Window size | |
| checksum | tcp.checksum -> anInteger | 
| TCP Checksum | |
| options_data | tcp.options_data-> aByteArray | False | 
| Bytearray containing the bytes of the TCP options part of the TCP header.  Returns False if header has no TCP options | |
| option_numbers | tcp.option_numbers -> aCFFIArray | False | 
| Byterray containing the option numbers of all this header's TCP options. Returns False if header has no TCP options | |
| urg_ptr | tcp.urgent -> anInteger | 
| TCP Urgent Pointer | |
| payload | tcp.payload -> aPayloadObject | 
| None if tcp had no payload, otherwise an object containing the packet's TCP payload | |
| Instance Function | |
| option(n) | tcp.option(n) -> aByteArray | True | False | 
| Bytearray containing option n's value bytes. Returns True if option n is present but has no value, or False if option n is not present in the header | |
Nevil Brownlee
Mon, 17 Jan 2017 (NZDT)