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new: implemented new (Linux only) packet.proxy module (closes #6).

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evilsocket 2018-03-28 15:17:28 +02:00
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2
README.md
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@ -14,7 +14,7 @@
A [precompiled version is available](https://github.com/bettercap/bettercap/releases) for each release, alternatively you can use the latest version of the source code from this repository in order to build your own binary.
Make sure you have a correctly configured **Go >= 1.8** environment, that `$GOPATH/bin` is in `$PATH` and the `libpcap-dev` package installed for your system, then:
Make sure you have a correctly configured **Go >= 1.8** environment, that `$GOPATH/bin` is in `$PATH`, that the `libpcap-dev` and `libnetfilter-queue-dev` package installed for your system and then:
$ go get github.com/bettercap/bettercap

6
glide.lock generated
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@ -1,5 +1,5 @@
hash: fbde0d2452ce166fdbca5d911aa533bef347f420e172f0801a98b90ec6ccf9be
updated: 2018-03-23T15:14:51.394587797+01:00
updated: 2018-03-28T13:41:06.165992863+02:00
imports:
- name: github.com/adrianmo/go-nmea
version: 22095aa1b48050243d3eb9a001ca80eb91a0c6fa
@ -16,6 +16,10 @@ imports:
- xpc
- name: github.com/bettercap/readline
version: 62c6fe6193755f722b8b8788aa7357be55a50ff1
- name: github.com/chifflier/nfqueue-go
version: 61ca646babef3bd4dea1deb610bfb0005c0a1298
subpackages:
- nfqueue
- name: github.com/dustin/go-humanize
version: bb3d318650d48840a39aa21a027c6630e198e626
- name: github.com/elazarl/goproxy

5
main.go
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@ -41,10 +41,11 @@ func main() {
sess.Register(modules.NewDHCP6Spoofer(sess))
sess.Register(modules.NewDNSSpoofer(sess))
sess.Register(modules.NewSniffer(sess))
sess.Register(modules.NewHttpServer(sess))
sess.Register(modules.NewPacketProxy(sess))
sess.Register(modules.NewTcpProxy(sess))
sess.Register(modules.NewHttpProxy(sess))
sess.Register(modules.NewHttpsProxy(sess))
sess.Register(modules.NewTcpProxy(sess))
sess.Register(modules.NewHttpServer(sess))
sess.Register(modules.NewRestAPI(sess))
sess.Register(modules.NewWOL(sess))
sess.Register(modules.NewWiFiModule(sess))

217
modules/packet_proxy.go Normal file
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@ -0,0 +1,217 @@
// +build !windows
// +build !darwin
package modules
import (
"fmt"
"io/ioutil"
golog "log"
"plugin"
"strings"
"syscall"
"github.com/bettercap/bettercap/core"
"github.com/bettercap/bettercap/log"
"github.com/bettercap/bettercap/session"
"github.com/chifflier/nfqueue-go/nfqueue"
)
type PacketProxy struct {
session.SessionModule
done chan bool
chainName string
rule string
queue *nfqueue.Queue
queueNum int
queueCb nfqueue.Callback
pluginPath string
plugin *plugin.Plugin
}
// this is ugly, but since we can only pass a function
// (not a struct function) as a callback to nfqueue,
// we need this in order to recover the state.
var mod *PacketProxy
func NewPacketProxy(s *session.Session) *PacketProxy {
mod = &PacketProxy{
SessionModule: session.NewSessionModule("packet.proxy", s),
done: make(chan bool),
queue: nil,
queueCb: nil,
queueNum: 0,
chainName: "OUTPUT",
}
mod.AddHandler(session.NewModuleHandler("packet.proxy on", "",
"Start the NFQUEUE based packet proxy.",
func(args []string) error {
return mod.Start()
}))
mod.AddHandler(session.NewModuleHandler("packet.proxy off", "",
"Stop the NFQUEUE based packet proxy.",
func(args []string) error {
return mod.Stop()
}))
mod.AddParam(session.NewIntParameter("packet.proxy.queue.num",
"0",
"NFQUEUE number to bind to."))
mod.AddParam(session.NewStringParameter("packet.proxy.chain",
"OUTPUT",
"",
"Chain name of the iptables rule."))
mod.AddParam(session.NewStringParameter("packet.proxy.plugin",
"",
"",
"Go plugin file to load and call for every packet."))
mod.AddParam(session.NewStringParameter("packet.proxy.rule",
"",
"",
"Any additional iptables rule to make the queue more selective (ex. --destination 8.8.8.8)."))
return mod
}
func (pp PacketProxy) Name() string {
return "packet.proxy"
}
func (pp PacketProxy) Description() string {
return "A Linux only module that relies on NFQUEUEs in order to filter packets."
}
func (pp PacketProxy) Author() string {
return "Simone Margaritelli <evilsocket@protonmail.com>"
}
func (pp *PacketProxy) destroyQueue() {
if pp.queue == nil {
return
}
pp.queue.DestroyQueue()
pp.queue.Close()
pp.queue = nil
}
func (pp *PacketProxy) runRule(enable bool) (err error) {
action := "-A"
if enable == false {
action = "-D"
}
args := []string{
action, pp.chainName,
}
if pp.rule != "" {
rule := strings.Split(pp.rule, " ")
args = append(args, rule...)
}
args = append(args, []string{
"-j", "NFQUEUE",
"--queue-num", fmt.Sprintf("%d", pp.queueNum),
}...)
log.Debug("iptables %s", args)
_, err = core.Exec("iptables", args)
return
}
func (pp *PacketProxy) Configure() (err error) {
golog.SetOutput(ioutil.Discard)
pp.destroyQueue()
if err, pp.queueNum = pp.IntParam("packet.proxy.queue.num"); err != nil {
return
} else if err, pp.chainName = pp.StringParam("packet.proxy.chain"); err != nil {
return
} else if err, pp.rule = pp.StringParam("packet.proxy.rule"); err != nil {
return
} else if err, pp.pluginPath = pp.StringParam("packet.proxy.plugin"); err != nil {
return
}
if pp.pluginPath == "" {
return fmt.Errorf("The parameter %s can not be empty.", core.Bold("packet.proxy.plugin"))
} else if core.Exists(pp.pluginPath) == false {
return fmt.Errorf("%s does not exist.", pp.pluginPath)
}
log.Info("Loading packet proxy plugin from %s ...", pp.pluginPath)
var ok bool
var sym plugin.Symbol
if pp.plugin, err = plugin.Open(pp.pluginPath); err != nil {
return
} else if sym, err = pp.plugin.Lookup("OnPacket"); err != nil {
return
} else if pp.queueCb, ok = sym.(func(*nfqueue.Payload) int); ok == false {
return fmt.Errorf("Symbol OnPacket is not a valid callback function.")
}
pp.queue = new(nfqueue.Queue)
if err = pp.queue.SetCallback(dummyCallback); err != nil {
return
} else if err = pp.queue.Init(); err != nil {
return
} else if err = pp.queue.Unbind(syscall.AF_INET); err != nil {
return
} else if err = pp.queue.Bind(syscall.AF_INET); err != nil {
return
} else if err = pp.queue.CreateQueue(pp.queueNum); err != nil {
return
} else if err = pp.queue.SetMode(nfqueue.NFQNL_COPY_PACKET); err != nil {
return
} else if err = pp.runRule(true); err != nil {
return
}
return nil
}
// we need this because for some reason we can't directly
// pass the symbol loaded from the plugin as a direct
// CGO callback ... ¯\_(ツ)_/¯
func dummyCallback(payload *nfqueue.Payload) int {
return mod.queueCb(payload)
}
func (pp *PacketProxy) Start() error {
if pp.Running() == true {
return session.ErrAlreadyStarted
} else if err := pp.Configure(); err != nil {
return err
}
return pp.SetRunning(true, func() {
log.Info("%s started on queue number %d", core.Green("packet.proxy"), pp.queueNum)
defer pp.destroyQueue()
pp.queue.Loop()
pp.done <- true
})
return nil
}
func (pp *PacketProxy) Stop() error {
return pp.SetRunning(false, func() {
pp.queue.StopLoop()
pp.runRule(false)
<-pp.done
})
}

47
modules/packet_proxy_unsupported.go Normal file
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@ -0,0 +1,47 @@
// +build windows darwin
package modules
import (
"errors"
"github.com/bettercap/bettercap/session"
)
var (
notSupported = errors.New("packet.proxy is not supported on this OS")
)
type PacketProxy struct {
session.SessionModule
}
func NewPacketProxy(s *session.Session) *PacketProxy {
return &PacketProxy{
SessionModule: session.NewSessionModule("packet.proxy", s),
}
}
func (pp PacketProxy) Name() string {
return "packet.proxy"
}
func (pp PacketProxy) Description() string {
return "Not supported on this OS"
}
func (pp PacketProxy) Author() string {
return "Simone Margaritelli <evilsocket@protonmail.com>"
}
func (pp *PacketProxy) Configure() (err error) {
return notSupported
}
func (pp *PacketProxy) Start() error {
return notSupported
}
func (pp *PacketProxy) Stop() error {
return notSupported
}

12
vendor/github.com/chifflier/nfqueue-go/.travis.yml generated vendored Normal file
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@ -0,0 +1,12 @@
language: go
go:
- 1.6
- tip
install:
- go get github.com/google/gopacket
- go get github.com/google/gopacket/layers
- go get github.com/chifflier/nfqueue-go/nfqueue
before_install:
- sudo apt-get -qq update
- sudo apt-get install -y pkg-config libnfnetlink-dev libnetfilter-queue-dev

339
vendor/github.com/chifflier/nfqueue-go/COPYING generated vendored Normal file
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@ -0,0 +1,339 @@
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54
vendor/github.com/chifflier/nfqueue-go/README.md generated vendored Normal file
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# nfqueue-go
[![Build Status](https://travis-ci.org/chifflier/nfqueue-go.svg?branch=master)](https://travis-ci.org/chifflier/nfqueue-go)
[![GoDoc](https://godoc.org/github.com/chifflier/nfqueue-go?status.svg)](https://godoc.org/github.com/chifflier/nfqueue-go/nfqueue)
nfqueue-go is a wrapper library for
[libnetfilter-queue](http://www.netfilter.org/projects/libnetfilter_queue/). The goal is to provide a library to gain access to packets queued by the kernel packet filter.
It is important to note that these bindings will not follow blindly libnetfilter_queue API. For ex., some higher-level wrappers will be provided for the open/bind/create mechanism (using one function call instead of three).
**The API is not yet stable.**
To use the library, a program must
- open a queue
- bind to a network family (`AF_PACKET` for IPv4)
- provide a callback function, which will be automatically called when a packet is received. The callback must return a verdict
- create the queue, providing the queue number (which must match the `--queue-num` from the iptables rules, see below
- run a loop, waiting for events. The program should also provide a clean way to exit the loop (for ex on `SIGINT`)
## Using library
```
import "github.com/chifflier/nfqueue-go/nfqueue"
```
## Example
See [test_nfqueue](nfqueue/test_nfqueue/test_nfqueue.go) for a minimal example, and [test_nfqueue_gopacket](nfqueue/test_nfqueue_gopacket/test_nfqueue.go) for an example using the [gopacket](https://github.com/google/gopacket) library to decode the packets.
## IPtables
You must add rules in netfilter to send packets to the userspace queue.
The number of the queue (--queue-num option in netfilter) must match the
number provided to create_queue().
Example of iptables rules:
iptables -A OUTPUT --destination 1.2.3.4 -j NFQUEUE --queue-num 0
Of course, you should be more restrictive, depending on your needs.
## Privileges
nfqueue-go does not require root privileges, but needs to open a netlink socket and send/receive packets to the kernel.
You have several options:
- Use the CAP_NET_ADMIN capability in order to allow your application to receive from and to send packets to kernel-space:
```setcap 'cap_net_admin=+ep' /path/to/program```
- Run your program as `root` and drop privileges
## License
This library is licensed under the GNU General Public License version 2, or (at your option) any later version.

50
vendor/github.com/chifflier/nfqueue-go/nfqueue/libnfqueue1.go generated vendored Normal file
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// +build libnfqueue1
package nfqueue
// This file contains code specific to versions >= 1.0 of libnetfilter_queue
/*
#include <stdio.h>
#include <stdint.h>
#include <arpa/inet.h>
#include <linux/netfilter.h>
#include <libnetfilter_queue/libnetfilter_queue.h>
*/
import "C"
import (
"log"
"unsafe"
)
// SetVerdictMark issues a verdict for a packet, but a mark can be set
//
// Every queued packet _must_ have a verdict specified by userspace.
func (p *Payload) SetVerdictMark(verdict int, mark uint32) error {
log.Printf("Setting verdict for packet %d: %d mark %lx\n",p.Id,verdict,mark)
C.nfq_set_verdict2(
p.c_qh,
C.u_int32_t(p.Id),
C.u_int32_t(verdict),
C.u_int32_t(mark),
0,nil)
return nil
}
// SetVerdictMarkModified issues a verdict for a packet, but replaces the
// packet with the provided one, and a mark can be set.
//
// Every queued packet _must_ have a verdict specified by userspace.
func (p *Payload) SetVerdictMarkModified(verdict int, mark uint32, data []byte) error {
log.Printf("Setting verdict for NEW packet %d: %d mark %lx\n",p.Id,verdict,mark)
C.nfq_set_verdict2(
p.c_qh,
C.u_int32_t(p.Id),
C.u_int32_t(verdict),
C.u_int32_t(mark),
C.u_int32_t(len(data)),
(*C.uchar)(unsafe.Pointer(&data[0])),
)
return nil
}

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vendor/github.com/chifflier/nfqueue-go/nfqueue/nfq_cb.go generated vendored Normal file
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package nfqueue
import (
"unsafe"
)
import "C"
/*
Cast argument to Queue* before calling the real callback
Notes:
- export cannot be done in the same file (nfqueue.go) else it
fails to build (multiple definitions of C functions)
See https://github.com/golang/go/issues/3497
See https://github.com/golang/go/wiki/cgo
- this cast is caused by the fact that cgo does not support
exporting structs
See https://github.com/golang/go/wiki/cgo
This function must _nerver_ be called directly.
*/
/*
BUG(GoCallbackWrapper): The return value from the Go callback is used as a
verdict. This works, and avoids packets without verdict to be queued, but
prevents using out-of-order replies.
*/
//export GoCallbackWrapper
func GoCallbackWrapper(ptr_q *unsafe.Pointer, ptr_nfad *unsafe.Pointer) int {
q := (*Queue)(unsafe.Pointer(ptr_q))
payload := build_payload(q.c_qh, ptr_nfad)
return q.cb(payload)
}

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vendor/github.com/chifflier/nfqueue-go/nfqueue/nfqueue.go generated vendored Normal file
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// Go bindings for the NFQUEUE netfilter target
// libnetfilter_queue is a userspace library providing an API to access packets
// that have been queued by the Linux kernel packet filter.
//
// This provides an easy way to filter packets from userspace, and use tools
// or libraries that are not accessible from kernelspace.
//
// BUG(nfqueue): This package currently displays lots of debug information
package nfqueue
// XXX we should use something like
// pkg-config --libs libnetfilter_queue
// #cgo pkg-config: libnetfilter_queue
/*
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <linux/netfilter.h>
#include <libnetfilter_queue/libnetfilter_queue.h>
extern int GoCallbackWrapper(void *data, void *nfad);
static inline ssize_t recv_to(int sockfd, void *buf, size_t len, int flags, int to);
int _process_loop(struct nfq_handle *h,
int *fd,
int flags,
int max_count) {
int rv;
char buf[65535];
int count;
count = 0;
(*fd) = nfq_fd(h);
if (fd < 0) {
return -1;
}
//avoid ENOBUFS on read() operation, otherwise the while loop is interrupted.
int opt = 1;
rv = setsockopt(*fd, SOL_NETLINK, NETLINK_NO_ENOBUFS, &opt, sizeof(int));
if (rv == -1) {
return -1;
}
while (h && *fd != -1) {
rv = recv_to(*fd, buf, sizeof(buf), flags, 500);
if (rv > 0) {
nfq_handle_packet(h, buf, rv);
count++;
if (max_count > 0 && count >= max_count) {
break;
}
} else if (rv < 0){
return rv;
}
}
return count;
}
void _stop_loop(int *fd) {
(*fd) = -1;
}
// recv with timeout using select
static inline ssize_t recv_to(int sockfd, void *buf, size_t len, int flags, int to) {
int rv;
ssize_t result;
fd_set readset;
// Initialize timeval struct
struct timeval timeout;
timeout.tv_sec = 0;
timeout.tv_usec = to * 1000;
// Initialize socket set
FD_ZERO(&readset);
FD_SET(sockfd, &readset);
rv = select(sockfd+1, &readset, (fd_set *) 0, (fd_set *) 0, &timeout);
// Check status
if (rv < 0) {
return -1;
} else if (rv > 0 && FD_ISSET(sockfd, &readset)) {
// Receive (ensure that the socket is set to non blocking mode!)
result = recv(sockfd, buf, len, flags);
return result;
}
return 0;
}
int c_nfq_cb(struct nfq_q_handle *qh,
struct nfgenmsg *nfmsg,
struct nfq_data *nfad, void *data) {
return GoCallbackWrapper(data, nfad);
}
// wrap nfq_get_payload so cgo always have the same prototype
// (libnetfilter_queue 0.17 uses a signed char)
static int _c_get_payload (struct nfq_data *nfad, unsigned char **data)
{
return nfq_get_payload (nfad, data);
}
*/
import "C"
import (
"errors"
"log"
"unsafe"
)
var ErrNotInitialized = errors.New("nfqueue: queue not initialized")
var ErrOpenFailed = errors.New("nfqueue: open failed")
var ErrRuntime = errors.New("nfqueue: runtime error")
var NF_DROP = C.NF_DROP
var NF_ACCEPT = C.NF_ACCEPT
var NF_QUEUE = C.NF_QUEUE
var NF_REPEAT = C.NF_REPEAT
var NF_STOP = C.NF_STOP
var NFQNL_COPY_NONE uint8 = C.NFQNL_COPY_NONE
var NFQNL_COPY_META uint8 = C.NFQNL_COPY_META
var NFQNL_COPY_PACKET uint8 = C.NFQNL_COPY_PACKET
// Prototype for a NFQUEUE callback.
// The callback receives the NFQUEUE ID of the packet, and
// the packet payload.
// Packet data start from the IP layer (ethernet information are not included).
// It must return the verdict for the packet.
type Callback func(*Payload) int
// Queue is an opaque structure describing a connection to a kernel NFQUEUE,
// and the associated Go callback.
type Queue struct {
c_h (*C.struct_nfq_handle)
c_qh (*C.struct_nfq_q_handle)
c_fd (*C.int)
cb Callback
}
// Init creates a netfilter queue which can be used to receive packets
// from the kernel.
func (q *Queue) Init() error {
log.Println("Opening queue")
q.c_h = C.nfq_open()
if (q.c_h == nil) {
log.Println("nfq_open failed")
return ErrOpenFailed
}
q.c_fd = (*C.int)(C.malloc(C.sizeof_int))
return nil
}
// SetCallback sets the callback function, fired when a packet is received.
func (q *Queue) SetCallback(cb Callback) error {
q.cb = cb
return nil
}
func (q *Queue) Close() {
if (q.c_h != nil) {
log.Println("Closing queue")
C.nfq_close(q.c_h)
q.c_h = nil
}
C.free(unsafe.Pointer(q.c_fd))
}
// Bind binds a Queue to a given protocol family.
//
// Usually, the family is syscall.AF_INET for IPv4, and syscall.AF_INET6 for IPv6
func (q *Queue) Bind(af_family int) error {
if (q.c_h == nil) {
return ErrNotInitialized
}
log.Println("Binding to selected family")
/* Errors in nfq_bind_pf are non-fatal ...
* This function just tells the kernel that nfnetlink_queue is
* the chosen module to queue packets to userspace.
*/
_ = C.nfq_bind_pf(q.c_h,C.u_int16_t(af_family))
return nil
}
// Unbind a queue from the given protocol family.
//
// Note that errors from this function can usually be ignored.
func (q *Queue) Unbind(af_family int) error {
if (q.c_h == nil) {
return ErrNotInitialized
}
log.Println("Unbinding to selected family")
rc := C.nfq_unbind_pf(q.c_h,C.u_int16_t(af_family))
if (rc < 0) {
log.Println("nfq_unbind_pf failed")
return ErrRuntime
}
return nil
}
// Create a new queue handle
//
// The queue must be initialized (using Init) and bound (using Bind), and
// a callback function must be set (using SetCallback).
func (q *Queue) CreateQueue(queue_num int) error {
if (q.c_h == nil) {
return ErrNotInitialized
}
if (q.cb == nil) {
return ErrNotInitialized
}
log.Println("Creating queue")
q.c_qh = C.nfq_create_queue(q.c_h,C.u_int16_t(queue_num),(*C.nfq_callback)(C.c_nfq_cb),unsafe.Pointer(q))
if (q.c_qh == nil) {
log.Println("nfq_create_queue failed")
return ErrRuntime
}
// Default mode
C.nfq_set_mode(q.c_qh,C.NFQNL_COPY_PACKET,0xffff)
return nil
}
// Destroy a queue handle
//
// This also unbind from the nfqueue handler, so you don't have to call Unbind()
// Note that errors from this function can usually be ignored.
func (q *Queue) DestroyQueue() error {
if (q.c_qh == nil) {
return ErrNotInitialized
}
log.Println("Destroy queue")
rc := C.nfq_destroy_queue(q.c_qh)
if (rc < 0) {
log.Println("nfq_destroy_queue failed")
return ErrRuntime
}
q.c_qh = nil
return nil
}
// SetMode sets the amount of packet data that nfqueue copies to userspace
//
// Default mode is NFQNL_COPY_PACKET
func (q *Queue) SetMode(mode uint8) error {
if (q.c_h == nil) {
return ErrNotInitialized
}
if (q.c_qh == nil) {
return ErrNotInitialized
}
C.nfq_set_mode(q.c_qh,C.u_int8_t(mode),0xffff)
return nil
}
// SetQueueMaxLen fixes the number of packets the kernel will store before internally before dropping upcoming packets
func (q *Queue) SetQueueMaxLen(maxlen uint32) error {
if (q.c_h == nil) {
return ErrNotInitialized
}
if (q.c_qh == nil) {
return ErrNotInitialized
}
C.nfq_set_queue_maxlen(q.c_qh,C.u_int32_t(maxlen))
return nil
}
// Main loop: Loop starts a loop, receiving kernel events
// and processing packets using the callback function.
func (q *Queue) Loop() error {
if (q.c_h == nil) {
return ErrNotInitialized
}
if (q.c_qh == nil) {
return ErrNotInitialized
}
if (q.cb == nil) {
return ErrNotInitialized
}
log.Println("Start Loop")
ret := C._process_loop(q.c_h, q.c_fd, 0, -1)
if ret < 0 {
return ErrRuntime
}
return nil
}
func (q *Queue) StopLoop() {
log.Println("Stop Loop")
C._stop_loop(q.c_fd)
}
// Payload is a structure describing a packet received from the kernel
type Payload struct {
c_qh (*C.struct_nfq_q_handle)
nfad *C.struct_nfq_data
// NFQueue ID of the packet
Id uint32
// Packet data
Data []byte
}
func build_payload(c_qh *C.struct_nfq_q_handle, ptr_nfad *unsafe.Pointer) *Payload {
var payload_data *C.uchar
var data []byte
nfad := (*C.struct_nfq_data)(unsafe.Pointer(ptr_nfad))
ph := C.nfq_get_msg_packet_hdr(nfad)
id := C.ntohl(C.uint32_t(ph.packet_id))
payload_len := C._c_get_payload(nfad, &payload_data)
if (payload_len >= 0) {
data = C.GoBytes(unsafe.Pointer(payload_data), C.int(payload_len))
}
p := new(Payload)
p.c_qh = c_qh
p.nfad = nfad
p.Id = uint32(id)
p.Data = data
return p
}
// SetVerdict issues a verdict for a packet.
//
// Every queued packet _must_ have a verdict specified by userspace.
func (p *Payload) SetVerdict(verdict int) error {
log.Printf("Setting verdict for packet %d: %d\n",p.Id,verdict)
C.nfq_set_verdict(p.c_qh,C.u_int32_t(p.Id),C.u_int32_t(verdict),0,nil)
return nil
}
// SetVerdictModified issues a verdict for a packet, but replaces the packet
// with the provided one.
//
// Every queued packet _must_ have a verdict specified by userspace.
func (p *Payload) SetVerdictModified(verdict int, data []byte) error {
log.Printf("Setting verdict for NEW packet %d: %d\n",p.Id,verdict)
C.nfq_set_verdict(
p.c_qh,
C.u_int32_t(p.Id),
C.u_int32_t(verdict),
C.u_int32_t(len(data)),
(*C.uchar)(unsafe.Pointer(&data[0])),
)
return nil
}
// Returns the packet mark
func (p *Payload) GetNFMark() uint32 {
return uint32(C.nfq_get_nfmark(p.nfad))
}
// Returns the interface that the packet was received through
func (p *Payload) GetInDev() uint32 {
return uint32(C.nfq_get_indev(p.nfad))
}
// Returns the interface that the packet will be routed out
func (p *Payload) GetOutDev() uint32 {
return uint32(C.nfq_get_outdev(p.nfad))
}
// Returns the physical interface that the packet was received through
func (p *Payload) GetPhysInDev() uint32 {
return uint32(C.nfq_get_physindev(p.nfad))
}
// Returns the physical interface that the packet will be routed out
func (p *Payload) GetPhysOutDev() uint32 {
return uint32(C.nfq_get_physoutdev(p.nfad))
}

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vendor/github.com/chifflier/nfqueue-go/nfqueue/test_nfqueue/test_nfqueue.go generated vendored Normal file
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package main
import (
"encoding/hex"
"fmt"
"github.com/chifflier/nfqueue-go/nfqueue"
"os"
"os/signal"
"syscall"
)
func real_callback(payload *nfqueue.Payload) int {
fmt.Println("Real callback")
fmt.Printf(" id: %d\n", payload.Id)
fmt.Printf(" mark: %d\n", payload.GetNFMark())
fmt.Printf(" in %d out %d\n", payload.GetInDev(), payload.GetOutDev())
fmt.Printf(" Φin %d Φout %d\n", payload.GetPhysInDev(), payload.GetPhysOutDev())
fmt.Println(hex.Dump(payload.Data))
fmt.Println("-- ")
payload.SetVerdict(nfqueue.NF_ACCEPT)
return 0
}
func main() {
q := new(nfqueue.Queue)
q.SetCallback(real_callback)
q.Init()
defer q.Close()
q.Unbind(syscall.AF_INET)
q.Bind(syscall.AF_INET)
q.CreateQueue(0)
q.SetMode(nfqueue.NFQNL_COPY_PACKET)
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
go func(){
for sig := range c {
// sig is a ^C, handle it
_ = sig
q.StopLoop()
}
}()
// XXX Drop privileges here
q.Loop()
q.DestroyQueue()
q.Close()
os.Exit(0)
}

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vendor/github.com/chifflier/nfqueue-go/nfqueue/test_nfqueue_gopacket/test_nfqueue.go generated vendored Normal file
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package main
import (
"encoding/hex"
"fmt"
"github.com/chifflier/nfqueue-go/nfqueue"
"os"
"os/signal"
"syscall"
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
)
func real_callback(payload *nfqueue.Payload) int {
fmt.Println("Real callback")
fmt.Printf(" id: %d\n", payload.Id)
fmt.Println(hex.Dump(payload.Data))
// Decode a packet
packet := gopacket.NewPacket(payload.Data, layers.LayerTypeIPv4, gopacket.Default)
// Get the TCP layer from this packet
if tcpLayer := packet.Layer(layers.LayerTypeTCP); tcpLayer != nil {
fmt.Println("This is a TCP packet!")
// Get actual TCP data from this layer
tcp, _ := tcpLayer.(*layers.TCP)
fmt.Printf("From src port %d to dst port %d\n", tcp.SrcPort, tcp.DstPort)
}
// Iterate over all layers, printing out each layer type
for _, layer := range packet.Layers() {
fmt.Println("PACKET LAYER:", layer.LayerType())
fmt.Println(gopacket.LayerDump(layer))
}
fmt.Println("-- ")
payload.SetVerdict(nfqueue.NF_ACCEPT)
return 0
}
func main() {
q := new(nfqueue.Queue)
q.SetCallback(real_callback)
q.Init()
q.Unbind(syscall.AF_INET)
q.Bind(syscall.AF_INET)
q.CreateQueue(0)
c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
go func(){
for sig := range c {
// sig is a ^C, handle it
_ = sig
q.StopLoop()
}
}()
// XXX Drop privileges here
q.Loop()
q.DestroyQueue()
q.Close()
os.Exit(0)
}