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#! @PYTHON3@
#
# Copyright (c) 2010 Nicira, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import binascii
import getopt
import struct
import sys
class PcapException(Exception):
pass
class PcapReader(object):
def __init__(self, file_name):
self.file = open(file_name, "rb")
header = self.file.read(24)
if len(header) != 24:
raise PcapException("end of file reading pcap header")
magic, version, thiszone, sigfigs, snaplen, network = \
struct.unpack(">6I", header)
if magic == 0xa1b2c3d4 or magic == 0xa1b23c4d:
self.header_format = ">4I"
elif magic == 0xd4c3b2a1 or magic == 0x4d3cb2a1:
self.header_format = "<4I"
else:
raise PcapException("bad magic %u reading pcap file "
"(expected 0xa1b2c3d4, 0xa1b23c4d, 0x4d3cb2a1 or "
"0xd4c3b2a1)" % magic)
def read(self):
header = self.file.read(16)
if len(header) == 0:
return None
elif len(header) != 16:
raise PcapException("end of file within pcap record header")
ts_sec, ts_usec, incl_len, orig_len = struct.unpack(self.header_format,
header)
packet = self.file.read(incl_len)
if len(packet) != incl_len:
raise PcapException("end of file reading pcap packet data")
return packet
argv0 = sys.argv[0]
def usage():
print("""\
%(argv0)s: print pcap file packet data as hex
usage: %(argv0)s FILE
where FILE is a PCAP file.
The following options are also available:
-h, --help display this help message
-V, --version display version information\
""" % {'argv0': argv0})
sys.exit(0)
if __name__ == "__main__":
try:
try:
options, args = getopt.gnu_getopt(sys.argv[1:], 'hV',
['help', 'version'])
except getopt.GetoptError as geo:
sys.stderr.write("%s: %s\n" % (argv0, geo.msg))
sys.exit(1)
for key, value in options:
if key in ['-h', '--help']:
usage()
elif key in ['-V', '--version']:
print("ovs-pcap (Open vSwitch) @VERSION@")
else:
sys.exit(0)
if len(args) != 1:
sys.stderr.write("%s: exactly 1 non-option argument required "
"(use --help for help)\n" % argv0)
sys.exit(1)
reader = PcapReader(args[0])
while True:
packet = reader.read()
if packet is None:
break
print(binascii.hexlify(packet).decode().strip())
except PcapException as e:
sys.stderr.write("%s: %s\n" % (argv0, e))
sys.exit(1)
# Local variables:
# mode: python
# End:
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