This is a static archive of our old Q&A Site. Please post any new questions and answers at ask.wireshark.org.

FCS calculation

0

Hi, I want to calculate the FCS in pcap library over the packet.can i do that.If yes then how please let us know. If it can be calculated then how we will verify that it is correct or not

Thanks and Advance.

asked 11 Jul '14, 04:08

irajeev's gravatar image

irajeev
11112
accept rate: 0%


One Answer:

0

I'm not sure if the PCAP library supports calculating the FCS. Problem is that you will not be able to record (and thus verify) the FCS, unless you're using a commercial capture solution that supports this.

The Ethernet FCS is just a CRC32 checksum, so you can use any library that has a CRC32 routine and pass the frame content.

answered 11 Jul '14, 04:12

Jasper's gravatar image

Jasper ♦♦
23.8k551284
accept rate: 18%

1

I'm not sure if the PCAP library supports calculating the FCS.

libpcap/WinPcap is for capturing packets, not processing them; it doesn't include code to calculate an FCS.

(11 Jul '14, 14:36) Guy Harris ♦♦