From 3674db7a9007133da99c7ba52f29b90df6ef5d1f Mon Sep 17 00:00:00 2001
From: dowright <dowright@nationofnobodies.com>
Date: Mon, 23 Aug 2021 21:14:42 -0700
Subject: [PATCH] work on new packet
---
new_packet.pyx | 32 +++++++++++++++++++++-----------
1 file changed, 21 insertions(+), 11 deletions(-)
diff --git a/new_packet.pyx b/new_packet.pyx
index 2c43733..d2ba92f 100644
--- a/new_packet.pyx
+++ b/new_packet.pyx
@@ -42,7 +42,7 @@ cdef class CPacket:
# return "%s packet, %s bytes" % (protocol, self.payload_len)
@staticmethod
- cdef nf_callback(self, nfq_q_handle *qh, nfgenmsg *nfmsg, nfq_data *nfa, void *data):
+ cdef int nf_callback(self, nfq_q_handle *qh, nfgenmsg *nfmsg, nfq_data *nfa, void *data):
# cdef NetfilterQueue nfqueue = <NetfilterQueue > data
# cdef object user_callback = <object > nfqueue.user_callback
@@ -50,12 +50,16 @@ cdef class CPacket:
packet = CPacket()
packet.parse(qh, nfa)
+ return 1
+
# NOTE: this will be callback target for nfqueue
cdef parse(self, nfq_q_handle *qh, nfq_data *nfa) nogil:
'''Alternate constructor. Used to start listener/proxy instances using nfqueue bindings.'''
'''Assign a packet from NFQ to this object. Parse the header and load local values.'''
+ cdef readonly unsigned char *data
+
self._qh = qh
self._nfa = nfa
self._hdr = nfq_get_msg_packet_hdr(nfa)
@@ -64,18 +68,18 @@ cdef class CPacket:
# self.hw_protocol = ntohs(self._hdr.hw_protocol)
# self.hook = self._hdr.hook
- self.payload_len = nfq_get_payload(self._nfa, & self.data)
+ self.payload_len = nfq_get_payload(self._nfa, &data)
# TODO: figure this out. cant use no gil if its here.
# if self.payload_len < 0:
# raise OSError("Failed to get payload of packet.")
# timestamp gets assigned via pointer/struct -> time_val: (t_sec, t_usec).
- nfq_get_timestamp(self._nfa, & self.timestamp)
+ nfq_get_timestamp(self._nfa, &self.timestamp)
self._mark = nfq_get_nfmark(nfa)
# splitting packet by tcp/ip layers
- cdef int error = self._parse()
+ self._parse(data)
# if (self.continue_condition):
# self._before_exit()
@@ -84,14 +88,12 @@ cdef class CPacket:
# with gil:
# callback(self)
- return 0
-
- cdef _parse(self):
+ cdef _parse(self, readonly unsigned char *data):
'''Index tcp/ip packet layers 3 & 4 for use as instance objects.
the before_exit method will be called before returning, which can be used to create
subclass specific objects like namedtuples or application layer data.'''
- cdef iphdr *ip_header = <iphdr*>self.data
+ cdef iphdr *ip_header = <iphdr*>data
cdef u_int8_t iphdr_len = ip_header.tos & 15 * 4
@@ -101,13 +103,21 @@ cdef class CPacket:
if (ip_header.protocol == IPPROTO_TCP):
- self.tcp_header = <tcphdr*>self.data[iphdr_len:]
+ *tcp_header = <tcphdr*>data[iphdr_len:]
+
+ self.tcp_header = tcp_header
if (ip_header.protocol == IPPROTO_UDP):
- self.udp_header = <udphdr*>self.data[iphdr_len:]
+
+ *udp_header = <udphdr*>data[iphdr_len:]
+
+ self.udp_header = udp_header
if (ip_header.protocol == IPPROTO_ICMP):
- self.icmp_header = <icmphdr*>self.data[iphdr_len:]
+
+ *icmp_header = <icmphdr*>data[iphdr_len:]
+
+ self.icmp_header = icmp_header
cdef void verdict(self, u_int32_t verdict):
'''Call appropriate set_verdict... function on packet.'''