Wireshark Filter for HTTP Protocol

Wireshark, a powerful network protocol analyzer, allows users to create custom filters to capture specific packets or protocols. One common use case is filtering for the HTTP protocol. In this article, we will explore how to create Wireshark filters for HTTP protocol.

To filter for packets that contain a specific sequence of bytes in the UDP header or payload, you can use the `contains` operator followed by the byte sequence. For example, to match packets containing the 3-byte sequence `0x81`, `0x60`, and `0x03`, you can use the following Wireshark filter:

`udp contains 81:60:03`

This filter will capture all packets that contain these bytes anywhere in the UDP header or payload.

Another useful feature of Wireshark filters is the ability to search for characters appearing anywhere in a field or protocol. For example, you can use the `contains` operator to search for the vendor identifier part (OUI) of the MAC address:

`eth.addr=00:06:5B`

This filter will restrict the display to only packets from DELL machines.

You can also use the `slice` feature to filter on the vendor identifier part (OUI) of the MAC address. For example:

`udp=81:60:03`

Note that the values for the byte sequence implicitly are in hexadecimal only.

In addition to filtering by protocol, you can also filter based on specific packet characteristics, such as the source and destination IP addresses. For example, to show only traffic within a local area network (LAN), you can use the following Wireshark filter:

`ip.src=192.168.0.0/16 and ip.dst=192.168.0.0/16`

This filter will capture all packets with source or destination IP addresses in the range `192.168.0.0/16`.

Wireshark filters can also be used to filter out noise, such as non-relevant traffic. For example, you can use the following Wireshark filter to show only SMB, NBNS, DCERPC, and DNS traffic:

`smb || nbns || dcerpc || nbss || dns`

Finally, you can use Wireshark filters to capture specific protocols or ports. For example, to show only SMTP (port 25) and ICMP traffic, you can use the following Wireshark filter:

`tcp.port eq 25 or icmp`

In conclusion, Wireshark filters are a powerful tool for capturing specific packets or protocols in network traffic. By using the `contains`, `slice`, and other operators, you can create custom filters to suit your needs. Whether you're troubleshooting network issues or monitoring network activity, Wireshark filters can help you focus on the most relevant data.

Wireshark filter http protocol