Working with captured packets
6.6. Finding packets
You can easily find packets once you have captured some packets or have read in a previously saved capture file. Simply select the Find Packet... menu item from the Edit menu. Ethereal will pop up the dialog box shown in Figure 6.9, “The "Find Packet" dialog box”.
6.6.1. The "Find Packet" dialog box
Figure 6.9. The "Find Packet" dialog box
You might first select the kind of thing to search for:
•Display filter
Simply enter a display filter string into the Filter: field, select a direction, and click on OK.
For example, to find the three way handshake for a connection from host 192.168.0.1, use the following filter string:
ip.addr==192.168.0.1 and tcp.flags.syn
For more details on display filters, see Section 6.2, “Filtering packets while viewing”
•Hex Value
Search for a specific byte sequence in the packet data.
For example, use "00:00" to find the next packet including two null bytes in the packet data.
•String
Find a string in the packet data, with various options.
The value to be found will by syntax checked while you type it in. If the syntax check of your value succeeded, the background of the entry field will turn green, if it fails, it will turn red.
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