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How to read pcapng (wireshark) files in Python?

I have a capture of some TCP packets in pcapng format and I'd like to open it in python to inspect the TCP payloads with address 192.168.1.198. I've only found this library: https://python-pcapng.readthedocs.io/en/latest/api/blocks.html but it does not support inspecting TCP payloads.
Is there an easy way?

You can use python-pcapng package. First install python-pcapng package by following command.
pip install python-pcapng
Then use following sample code.
from pcapng import FileScanner
with open(r'C:\Users\zahangir\Downloads\MDS19 Wireshark Log 08072021.pcapng', 'rb') as fp:
scanner = FileScanner(fp)
for block in scanner:
print(block)
print(block._raw) #byte type raw data
Above code worked for me.
Reference: https://pypi.org/project/python-pcapng/

Getting a particular package from the pcap file using the Scapy module (python)

Is there a way to load a particular package from the pcap file using Scapy?
I know that I can load a specific number of packages using the' sniff' function and count attribute, e. g.'
sniff(offline='file.pcap', prn=action, count=31)
However, I need to get a 30th packet without loading the previous packets.
In other words, I am not satisfied with such an example:
packages = (pkt for pkt in sniff (offline=path, prn=action, count=31)
print(packages[30])
The attempt to load a millionth of a package is too long.

Each packet header states how long it is. Once the parser has read that header, it can calculate the position of the next one. So as far as I know, you cannot open a pcap file and instantly locate packet 30; you'll need to parse the headers of the first 29.
But you don't have to keep all packets in memory either, as long as you process them while receiving.
i = 0
for pkt in sniff(offline=path, prn=action):
if i == 30:
print pkt
break

Reading PCAP file with scapy

I have about 10GB pcap data with IPv6 traffic to analyze infos stored in IPv6 header and other extension header. To do this I decided to use Scapy framework. I tried rdpcap function , but for such big files it is not recommended. It tries to load all file into memory and get stuck in my case.
I found in the Net that in such situation sniff is recommended, my code look like:
def main():
sniff(offline='traffic.pcap', prn=my_method,store=0)
def my_method(packet):
packet.show()
In function called my_method I receive each packet separately and I can parse them, but....
When I call show function with is in-build framework method I got sth like this:
When opened in wireshark I got properly looking packet:
Could you tell me how to parse this packets in scapy to get proper results?
EDIT:
According to the discussion in comments I found a way to parse PCAP file with Python. In my opinion the easies way is to use pyshark framework:
import pyshark
pcap = pyshark.FileCapture(pcap_path) ### for reading PCAP file
It is possible to easily iterate read file with for loop
for pkt in pcap:
#do what you want
For parsing IPv6 header following methods may be useful:
pkt['ipv6'].tclass #Traffic class field
pkt['ipv6'].tclass_dscp #Traffic class DSCP field
pkt['ipv6'].tclass_ecn #Traffic class ECN field
pkt['ipv6'].flow #Flow label field
pkt['ipv6'].plen #Payload length field
pkt['ipv6'].nxt #Next header field
pkt['ipv6'].hlim #Hop limit field

Update
The latest scapy versions now support ipv6 parsing.
So to parse an ipv6 ".pcap" file with scapy now it can be done like so:
from scapy.all import *
scapy_cap = rdpcap('file.pcap')
for packet in scapy_cap:
print packet[IPv6].src
Now as I had commented back when this question was originally asked, for older
scapy versions (that don't support ipv6 parsing):
pyshark can be used instead (pyshark is a tshark wrapper) like so:
import pyshark
shark_cap = pyshark.FileCapture('file.pcap')
for packet in shark_cap:
print packet.ipv6.src
or even of course tshark (kind of the terminal version of wireshark):
$ tshark -r file.pcap -q -Tfields -e ipv6.src

If you want to keep using scapy and read the file Iteratively I'd recommend you to give it a shot to PcapReader()
It would do the same you tried to do with pyshark but in Scapy
from scapy.all import *
for packet in PcapReader('file.pcap')
try:
print(packet[IPv6].src)
except:
pass
I'd recommend wrapping this around just as a failsafe if you have any packet that does not have an IPv6 address.

Close rdpcap function - Scapy

I have a script that loops through a lot of pcap files. For each pcap file I need to read it and then write some information to a txt file. I'm using the rdcap function from Scapy. Is there anyway to close the pcap file once I'm done reading it? My script has a memory leak and I'm worried this may be the culprit (via leaving many pcap files essentially open)

Inspecting Scapy's source code reveals that the rdpcap function neglects to close the pcap file:
#conf.commands.register
def rdpcap(filename, count=-1):
"""Read a pcap file and return a packet list
count: read only <count> packets"""
return PcapReader(filename).read_all(count=count)
I suggest you implement your own version of this function as follows:
def rdpcap_and_close(filename, count=-1):
"""Read a pcap file, return a packet list and close the file
count: read only <count> packets"""
pcap_reader = PcapReader(filename)
packets = pcap_reader.read_all(count=count)
pcap_reader.close()
return packets
I've created an issue for this problem here.
EDIT: The issue has been resolved in this changeset.

Scapy PcapReader and packets time

I'm reading a PCAP file using Scapy using a script such as the (semplified) following one:
#! /usr/bin/env python
from scapy.all import *
# ...
myreader = PcapReader(myinputfile)
for p in myreader:
pkt = p.payload
print pkt.time
In this case the packets time is not relative to PCAP capture time, but starts from the instant I've launched my script.
I'd like to start from 0.0 or to be relative to the PCAP capture.
How can I fix it (possibly without "manually" retrieving the first packet time and repeatedly using math to fix the problem)?

I saw that using pkt.time is wrong, in this case.
I should print p.time instead.