def ip_ok(self, tp=False):
try:
ip = self.ip()
except:
return False
# IP header checksum
s = dpkt.in_cksum(ip.pack_hdr() + ip.opts)
if s != 0: return False
if not tp: return True
else: pass # will compute transport protocol checksum
# do we have all the data?
if len(str(ip)) != ip.len:
return True
# get payload
try:
if self.is_tcp(): p = str(self.tcp())
else: p = str(self.udp())
except:
return True
s = dpkt.struct.pack('>4s4sxBH', ip.src, ip.dst, ip.p, len(p))
s = dpkt.in_cksum(s + p)
if s != 0: return False
return True
def ip_ok(self, tp=False):
try: ip = self.ip()
except: return False
# IP header checksum
s = dpkt.in_cksum(ip.pack_hdr() + ip.opts)
if s != 0: return False
if not tp: return True
else: pass # will compute transport protocol checksum
# do we have all the data?
if len(str(ip)) != ip.len:
return True
# get payload
try:
if self.is_tcp(): p = str(self.tcp())
else: p = str(self.udp())
except: return True
s = dpkt.struct.pack('>4s4sxBH', ip.src, ip.dst, ip.p, len(p))
s = dpkt.in_cksum(s+p)
if s != 0: return False
return True
def compare_checksum(cnt):
s = 'A' * 80
start = time.time()
for i in range(cnt):
dpkt.in_cksum(s)
print('dpkt.in_cksum:', cnt / (time.time() - start), 'pps')
start = time.time()
for i in range(cnt):
dnet.ip_cksum_carry(dnet.ip_cksum_add(s, 0))
print('dnet.ip_cksum_add/carry:', cnt / (time.time() - start), 'pps')
def compare_checksum(cnt):
s = 'A' * 80
start = time.time()
for i in range(cnt):
dpkt.in_cksum(s)
print('dpkt.in_cksum:', cnt / (time.time() - start), 'pps')
start = time.time()
for i in range(cnt):
dnet.ip_cksum_carry(dnet.ip_cksum_add(s, 0))
print('dnet.ip_cksum_add/carry:', cnt / (time.time() - start), 'pps')
def parseOspfMsg(msg, verbose=1, level=0):
iph = parseIpHdr(msg[:IP_HDR_LEN], verbose, level)
if not iph:
return None
msg = msg[IP_HDR_LEN:]
if dpkt.in_cksum(msg):
LOG.error('[ERROR] OSPF header checksum error.')
return None
ospfh = parseOspfHdr(msg[:OSPF_HDR_LEN], verbose, level+1)
rv = { "T": ospfh["TYPE"],
"L": ospfh["LEN"],
"H": iph,
"V": ospfh,
}
if MSG_TYPES[ospfh["TYPE"]] == "HELLO":
rv["V"]["V"] = parseOspfHello(msg[OSPF_HDR_LEN:ospfh["LEN"]], verbose, level+2)
elif MSG_TYPES[ospfh["TYPE"]] == "DBDESC":
rv["V"]["V"] = parseOspfDesc(msg[OSPF_HDR_LEN:ospfh["LEN"]], verbose, level+2)
elif MSG_TYPES[ospfh["TYPE"]] == "LSREQ":
rv["V"]["V"] = parseOspfLsReq(msg[OSPF_HDR_LEN:], verbose, level+1)
elif MSG_TYPES[ospfh["TYPE"]] == "LSUPD":
rv["V"]["V"] = parseOspfLsUpd(msg[OSPF_HDR_LEN:], verbose, level+2)
elif MSG_TYPES[ospfh["TYPE"]] == "LSACK":
rv["V"]["V"] = parseOspfLsAck(msg[OSPF_HDR_LEN:], verbose, level+2)
return rv
def on_vrrp_packet (header, data):
ethernet_frame = ethernet.Ethernet(data)
ip_packet = ethernet_frame.data
vrrp_packet = ip_packet.vrrp
# skip over IPv6 right now, IPv4 needs fixing first
if vrrp_packet.version == 3:
return
print ""
print ip_packet.unpack
print vrrp_packet.unpack
print vrrp_packet.checksum
vrrp_packet.checksum = 0
print dpkt.in_cksum(vrrp_packet.pack_hdr() + vrrp_packet.addrs[0])
version = vrrp_packet.version
for i in vrrp_packet.addrs:
print socket.inet_ntop(ip_version_map[version], i)
def __verify_checksums(cls, ippacket):
if dpkt.in_cksum(ippacket.pack_hdr() + str(ippacket.opts)) != 0:
return False
if (ippacket.off & (dpkt.ip.IP_MF | dpkt.ip.IP_OFFMASK)) != 0:
return True
p = str(ippacket.data)
s = dpkt.struct.pack('>4s4sxBH', ippacket.src, ippacket.dst,
ippacket.p, len(p))
s = dpkt.in_cksum_add(0, s)
s = dpkt.in_cksum_add(s, p)
return dpkt.in_cksum_done(s) == 0
def dpkt_fix_checksums(pkt):
try:
eth = dpkt.ethernet.Ethernet(pkt)
ip = eth.data
ip.sum = 0
if type(ip.data) in (dpkt.tcp.TCP, dpkt.udp.UDP):
psdhdr = ip.src + ip.dst + struct.pack('!HH', ip.p, ip.len - 20)
ip.data.sum = 0
ip.data.sum = dpkt.in_cksum(psdhdr + str(ip.data))
padding = pkt[len(eth):]
pkt = str(eth) + padding
except:
logging.exception('')
return pkt
def __str__(self):
if self.sum == 0:
self.sum = dpkt.in_cksum(self.pack_hdr() + self.opts)
if (self.p == 6 or self.p == 17) and (self.off & (IP_MF | IP_OFFMASK)) == 0 and \
isinstance(self.data, dpkt.Packet) and self.data.sum == 0:
# Set zeroed TCP and UDP checksums for non-fragments.
p = str(self.data)
s = dpkt.struct.pack('>4s4sxBH', self.src, self.dst,
self.p, len(p))
s = dpkt.in_cksum_add(0, s)
s = dpkt.in_cksum_add(s, p)
self.data.sum = dpkt.in_cksum_done(s)
if self.p == 17 and self.data.sum == 0:
self.data.sum = 0xffff # RFC 768
# XXX - skip transports which don't need the pseudoheader
return self.pack_hdr() + self.opts + str(self.data)
def __str__(self):
if self.sum == 0:
self.sum = dpkt.in_cksum(self.pack_hdr() + str(self.opts))
if (self.p == 6 or self.p == 17) and (self.off & (IP_MF | IP_OFFMASK)) == 0 and \
isinstance(self.data, dpkt.Packet) and self.data.sum == 0:
# Set zeroed TCP and UDP checksums for non-fragments.
p = str(self.data)
s = dpkt.struct.pack('>4s4sxBH', self.src, self.dst,
self.p, len(p))
s = dpkt.in_cksum_add(0, s)
s = dpkt.in_cksum_add(s, p)
self.data.sum = dpkt.in_cksum_done(s)
if self.p == 17 and self.data.sum == 0:
self.data.sum = 0xffff # RFC 768
# XXX - skip transports which don't need the pseudoheader
return self.pack_hdr() + str(self.opts) + str(self.data)
def unpack(self, buf):
# Extract and remove the checksum from the end
self.csum = struct.unpack('!H', buf[-2:])[0]
buf = buf[:-2]
# Check the checksum - someone else can complain if it's wrong
self.buf_csum = dpkt.in_cksum(buf)
# Unpack the header
dpkt.Packet.unpack(self, buf)
# Now process the TLV's
buf = self.data
l = []
while buf:
tlv = TLV(buf)
l.append(tlv)
buf = buf[len(tlv):]
self.data = l
def unpack(self, buf):
# Extract and remove the checksum from the end
self.csum = struct.unpack('!H', buf[-2:])[0]
buf = buf[:-2]
# Check the checksum - someone else can complain if it's wrong
self.buf_csum = dpkt.in_cksum(buf)
# Unpack the header
dpkt.Packet.unpack(self, buf)
# Now process the TLV's
buf = self.data
l = []
while buf:
tlv = TLV(buf)
l.append(tlv)
buf = buf[len(tlv):]
self.data = l
def __str__(self):
data = ''.join(self.addrs) + self.auth
if not self.sum:
self.sum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data
def __str__(self):
if not self.sum:
self.sum = dpkt.in_cksum(dpkt.Packet.__str__(self))
return dpkt.Packet.__str__(self)
def __str__(self):
if not self.sum:
self.sum = dpkt.in_cksum(dpkt.Packet.__str__(self))
return dpkt.Packet.__str__(self)
def __str__(self):
data = ''.join(self.addrs) + self.auth
if not self.sum:
self.sum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data
def __str__(self):
data = ''.join(map(str, self.data))
if not self.sum:
self.sum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data
def __str__(self):
data = ''.join(map(str, self.data))
csum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data + struct.pack('!H', csum)
def __str__(self):
data = ''.join(map(str, self.data))
csum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data + struct.pack('!H', csum)
def __str__(self):
data = ''.join(map(str, self.data))
if not self.sum:
self.sum = dpkt.in_cksum(self.pack_hdr() + data)
return self.pack_hdr() + data
