Python: Scapy: How to read IP flags

Question

I am trying to figure out how to read IP flags (not TCP) using scapy library. I know it is stored in "flags" and it is FlagsField type. According to IP protocol specification there are 3 flags R, MF, and DF. I've search, and searched and could not find any info on how to read these flags. Any ideas?

Thank you all for your input.

Answer 1

For example, creating an IP packet with the DF (Don't Fragment) flag set:

>>> packet = IP(flags=2)  # alternatively, IP(flags='DF')
>>> packet
<IP  flags=DF |>

Reading a packet's flags:

>>> packet.flags
2

As for the flag bits, Wikipedia outlines this succinctly. It's a three-bit value with the following meaning:

• bit 0: Reserved; must be zero.
• bit 1: Don't Fragment (DF)
• bit 2: More Fragments (MF)