Very dirty/experimental replacement of nfqueue with native github.com/subgraph/go-nfnetlink package.

shw_dev
shw 7 years ago
parent 4955c6a66b
commit 8fe02202de

@ -1,201 +0,0 @@
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@ -1,41 +0,0 @@
package nfqueue
import "sync"
type multiQueue struct {
qs []*nfQueue
}
func NewMultiQueue(min, max uint16) (mq *multiQueue) {
mq = &multiQueue{make([]*nfQueue, 0, max-min)}
for i := min; i < max; i++ {
mq.qs = append(mq.qs, NewNFQueue(i))
}
return mq
}
func (mq *multiQueue) Process() <-chan *Packet {
var (
wg sync.WaitGroup
out = make(chan *Packet, len(mq.qs))
)
for _, q := range mq.qs {
wg.Add(1)
go func(ch <-chan *Packet) {
for pkt := range ch {
out <- pkt
}
wg.Done()
}(q.Process())
}
go func() {
wg.Wait()
close(out)
}()
return out
}
func (mq *multiQueue) Destroy() {
for _, q := range mq.qs {
q.Destroy()
}
}

@ -1,87 +0,0 @@
#include "nfqueue.h"
#include "_cgo_export.h"
int nfqueue_cb_new(struct nfq_q_handle *qh, struct nfgenmsg *nfmsg, struct nfq_data *nfa, void *data) {
struct nfqnl_msg_packet_hdr *ph = nfq_get_msg_packet_hdr(nfa);
// struct nfqnl_msg_packet_hw *hwph = nfq_get_packet_hw(nfa);
if(ph == NULL) {
return 1;
}
int id = ntohl(ph->packet_id);
unsigned char * payload;
unsigned char * saddr, * daddr;
uint16_t sport = 0, dport = 0, checksum = 0;
uint32_t mark = nfq_get_nfmark(nfa);
int len = nfq_get_payload(nfa, &payload);
if(len < sizeof(struct iphdr)) {
return 0;
}
struct iphdr * ip = (struct iphdr *) payload;
if(ip->version == 4) {
uint32_t ipsz = (ip->ihl << 2);
if(len < ipsz) {
return 0;
}
len -= ipsz;
payload += ipsz;
saddr = (unsigned char *)&ip->saddr;
daddr = (unsigned char *)&ip->daddr;
if(ip->protocol == IPPROTO_TCP) {
if(len < sizeof(struct tcphdr)) {
return 0;
}
struct tcphdr *tcp = (struct tcphdr *) payload;
uint32_t tcpsz = (tcp->doff << 2);
if(len < tcpsz) {
return 0;
}
len -= tcpsz;
payload += tcpsz;
sport = ntohs(tcp->source);
dport = ntohs(tcp->dest);
checksum = ntohs(tcp->check);
} else if(ip->protocol == IPPROTO_UDP) {
if(len < sizeof(struct udphdr)) {
return 0;
}
struct udphdr *u = (struct udphdr *) payload;
len -= sizeof(struct udphdr);
payload += sizeof(struct udphdr);
sport = ntohs(u->source);
dport = ntohs(u->dest);
checksum = ntohs(u->check);
}
} else {
struct ipv6hdr *ip6 = (struct ipv6hdr*) payload;
saddr = (unsigned char *)&ip6->saddr;
daddr = (unsigned char *)&ip6->daddr;
//ipv6
}
//pass everything we can and let Go handle it, I'm not a big fan of C
uint32_t verdict = go_nfq_callback(id, ntohs(ph->hw_protocol), ph->hook, &mark, ip->version, ip->protocol,
ip->tos, ip->ttl, saddr, daddr, sport, dport, checksum, len, payload, data);
return nfq_set_verdict2(qh, id, verdict, mark, 0, NULL);
}
void loop_for_packets(struct nfq_handle *h) {
int fd = nfq_fd(h);
char buf[4096] __attribute__ ((aligned));
int rv;
while ((rv = recv(fd, buf, sizeof(buf), 0)) && rv >= 0) {
nfq_handle_packet(h, buf, rv);
}
}

@ -1,180 +0,0 @@
package nfqueue
/*
#cgo LDFLAGS: -lnetfilter_queue
#cgo CFLAGS: -Wall
#include "nfqueue.h"
*/
import "C"
import (
"net"
"os"
"runtime"
"sync"
"syscall"
"time"
"unsafe"
)
type nfQueue struct {
DefaultVerdict Verdict
Timeout time.Duration
qid uint16
h *C.struct_nfq_handle
//qh *C.struct_q_handle
qh *C.struct_nfq_q_handle
fd int
lk sync.Mutex
pktch chan *Packet
}
func NewNFQueue(qid uint16) (nfq *nfQueue) {
if os.Geteuid() != 0 {
}
if os.Geteuid() != 0 {
panic("Must be ran by root.")
}
nfq = &nfQueue{DefaultVerdict: ACCEPT, Timeout: time.Microsecond * 5, qid: qid}
return nfq
}
/*
This returns a channel that will receive packets,
the user then must call pkt.Accept() or pkt.Drop()
*/
func (this *nfQueue) Process() <-chan *Packet {
if this.h != nil {
return this.pktch
}
this.init()
go func() {
runtime.LockOSThread()
C.loop_for_packets(this.h)
}()
return this.pktch
}
func (this *nfQueue) init() {
var err error
if this.h, err = C.nfq_open(); err != nil || this.h == nil {
panic(err)
}
//if this.qh, err = C.nfq_create_queue(this.h, qid, C.get_cb(), unsafe.Pointer(nfq)); err != nil || this.qh == nil {
this.pktch = make(chan *Packet, 1)
if C.nfq_unbind_pf(this.h, C.AF_INET) < 0 {
this.Destroy()
panic("nfq_unbind_pf(AF_INET) failed, are you running root?.")
}
if C.nfq_unbind_pf(this.h, C.AF_INET6) < 0 {
this.Destroy()
panic("nfq_unbind_pf(AF_INET6) failed.")
}
if C.nfq_bind_pf(this.h, C.AF_INET) < 0 {
this.Destroy()
panic("nfq_bind_pf(AF_INET) failed.")
}
if C.nfq_bind_pf(this.h, C.AF_INET6) < 0 {
this.Destroy()
panic("nfq_bind_pf(AF_INET6) failed.")
}
if this.qh, err = C.create_queue(this.h, C.uint16_t(this.qid), unsafe.Pointer(this)); err != nil || this.qh == nil {
C.nfq_close(this.h)
panic(err)
}
this.fd = int(C.nfq_fd(this.h))
if C.nfq_set_mode(this.qh, C.NFQNL_COPY_PACKET, 0xffff) < 0 {
this.Destroy()
panic("nfq_set_mode(NFQNL_COPY_PACKET) failed.")
}
if C.nfq_set_queue_maxlen(this.qh, 1024*8) < 0 {
this.Destroy()
panic("nfq_set_queue_maxlen(1024 * 8) failed.")
}
}
func (this *nfQueue) Destroy() {
this.lk.Lock()
defer this.lk.Unlock()
if this.fd != 0 && this.Valid() {
syscall.Close(this.fd)
}
if this.qh != nil {
C.nfq_destroy_queue(this.qh)
this.qh = nil
}
if this.h != nil {
C.nfq_close(this.h)
this.h = nil
}
if this.pktch != nil {
close(this.pktch)
}
}
func (this *nfQueue) Valid() bool {
return this.h != nil && this.qh != nil
}
//export go_nfq_callback
func go_nfq_callback(id uint32, hwproto uint16, hook uint8, mark *uint32,
version, protocol, tos, ttl uint8, saddr, daddr unsafe.Pointer,
sport, dport, checksum uint16, payload_len uint32, payload, nfqptr unsafe.Pointer) (v uint32) {
var (
nfq = (*nfQueue)(nfqptr)
ipver = IPVersion(version)
ipsz = C.int(ipver.Size())
)
bs := C.GoBytes(payload, (C.int)(payload_len))
verdict := make(chan uint32, 1)
pkt := Packet{
QueueId: nfq.qid,
Id: id,
HWProtocol: hwproto,
Hook: hook,
Mark: *mark,
Payload: bs,
IPHeader: &IPHeader{
Version: ipver,
Protocol: IPProtocol(protocol),
Tos: tos,
TTL: ttl,
Src: net.IP(C.GoBytes(saddr, ipsz)),
Dst: net.IP(C.GoBytes(daddr, ipsz)),
},
TCPUDPHeader: &TCPUDPHeader{
SrcPort: sport,
DstPort: dport,
Checksum: checksum,
},
verdict: verdict,
}
nfq.pktch <- &pkt
select {
case v = <-pkt.verdict:
*mark = pkt.Mark
case <-time.After(nfq.Timeout):
v = uint32(nfq.DefaultVerdict)
}
return v
}

@ -1,27 +0,0 @@
#pragma once
// #define _BSD_SOURCE
// #define __BSD_SOURCE
// #define __FAVOR_BSD // Just Using _BSD_SOURCE didn't work on my system for some reason
// #define __USE_BSD
#include <stdlib.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/ipv6.h>
#include <linux/netfilter.h>
#include <libnetfilter_queue/libnetfilter_queue.h>
// extern int nfq_callback(uint8_t version, uint8_t protocol, unsigned char *saddr, unsigned char *daddr,
// uint16_t sport, uint16_t dport, unsigned char * extra, void* data);
int nfqueue_cb_new(struct nfq_q_handle *qh, struct nfgenmsg *nfmsg, struct nfq_data *nfa, void *data);
void loop_for_packets(struct nfq_handle *h);
static inline struct nfq_q_handle * create_queue(struct nfq_handle *h, uint16_t num, void *data) {
//we use this because it's more convient to pass the callback in C
return nfq_create_queue(h, num, &nfqueue_cb_new, data);
}

@ -1,145 +0,0 @@
package nfqueue
import (
"fmt"
"net"
"syscall"
)
type (
IPVersion uint8
IPProtocol uint8
Verdict uint8
)
const (
IPv4 = IPVersion(4)
IPv6 = IPVersion(6)
//convience really
IGMP = IPProtocol(syscall.IPPROTO_IGMP)
RAW = IPProtocol(syscall.IPPROTO_RAW)
TCP = IPProtocol(syscall.IPPROTO_TCP)
UDP = IPProtocol(syscall.IPPROTO_UDP)
ICMP = IPProtocol(syscall.IPPROTO_ICMP)
ICMPv6 = IPProtocol(syscall.IPPROTO_ICMPV6)
)
const (
DROP Verdict = iota
ACCEPT
STOLEN
QUEUE
REPEAT
STOP
)
var (
ErrVerdictSentOrTimedOut error = fmt.Errorf("The verdict was already sent or timed out.")
)
func (v IPVersion) String() string {
switch v {
case IPv4:
return "IPv4"
case IPv6:
return "IPv6"
}
return fmt.Sprintf("<unknown ip version, %d>", uint8(v))
}
// Returns the byte size of the ip, IPv4 = 4 bytes, IPv6 = 16
func (v IPVersion) Size() int {
switch v {
case IPv4:
return 4
case IPv6:
return 16
}
return 0
}
func (p IPProtocol) String() string {
switch p {
case RAW:
return "RAW"
case TCP:
return "TCP"
case UDP:
return "UDP"
case ICMP:
return "ICMP"
case ICMPv6:
return "ICMPv6"
case IGMP:
return "IGMP"
}
return fmt.Sprintf("<unknown protocol, %d>", uint8(p))
}
func (v Verdict) String() string {
switch v {
case DROP:
return "DROP"
case ACCEPT:
return "ACCEPT"
}
return fmt.Sprintf("<unsupported verdict, %d>", uint8(v))
}
type IPHeader struct {
Version IPVersion
Tos, TTL uint8
Protocol IPProtocol
Src, Dst net.IP
}
type TCPUDPHeader struct {
SrcPort, DstPort uint16
Checksum uint16 //not implemented
}
// TODO handle other protocols
type Packet struct {
QueueId uint16
Id uint32
HWProtocol uint16
Hook uint8
Mark uint32
Payload []byte
*IPHeader
*TCPUDPHeader
verdict chan uint32
}
func (pkt *Packet) String() string {
return fmt.Sprintf("<Packet QId: %d, Id: %d, Type: %s, Src: %s:%d, Dst: %s:%d, Mark: 0x%X, Checksum: 0x%X, TOS: 0x%X, TTL: %d>",
pkt.QueueId, pkt.Id, pkt.Protocol, pkt.Src, pkt.SrcPort, pkt.Dst, pkt.DstPort, pkt.Mark, pkt.Checksum, pkt.Tos, pkt.TTL)
}
func (pkt *Packet) setVerdict(v Verdict) (err error) {
defer func() {
if x := recover(); x != nil {
err = ErrVerdictSentOrTimedOut
}
}()
pkt.verdict <- uint32(v)
close(pkt.verdict)
return err
}
func (pkt *Packet) Accept() error {
return pkt.setVerdict(ACCEPT)
}
func (pkt *Packet) Drop() error {
return pkt.setVerdict(DROP)
}
//HUGE warning, if the iptables rules aren't set correctly this can cause some problems.
// func (pkt *Packet) Repeat() error {
// return this.SetVerdict(REPEAT)
// }

@ -5,7 +5,8 @@ import (
"strings"
"sync"
"github.com/subgraph/fw-daemon/nfqueue"
// "github.com/subgraph/go-nfnetlink"
"github.com/google/gopacket"
)
type dnsCache struct {
@ -21,9 +22,9 @@ func newDNSCache() *dnsCache {
}
}
func (dc *dnsCache) processDNS(pkt *nfqueue.Packet) {
func (dc *dnsCache) processDNS(pkt gopacket.Packet) {
dns := &dnsMsg{}
if !dns.Unpack(pkt.Payload) {
if !dns.Unpack(pkt.ApplicationLayer().Payload()) {
log.Warning("Failed to Unpack DNS message")
return
}

@ -5,7 +5,12 @@ import (
"strings"
"sync"
"github.com/subgraph/fw-daemon/nfqueue"
// "encoding/binary"
// nfnetlink "github.com/subgraph/go-nfnetlink"
nfqueue "github.com/subgraph/go-nfnetlink/nfqueue"
// "github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/subgraph/go-procsnitch"
"net"
)
@ -30,7 +35,7 @@ type pendingConnection interface {
type pendingPkt struct {
pol *Policy
name string
pkt *nfqueue.Packet
pkt *nfqueue.NFQPacket
pinfo *procsnitch.Info
}
@ -46,11 +51,27 @@ func (pp *pendingPkt) hostname() string {
return pp.name
}
func (pp *pendingPkt) dst() net.IP {
return pp.pkt.Dst
dst := pp.pkt.Packet.NetworkLayer().NetworkFlow().Dst()
if dst.EndpointType() != layers.EndpointIPv4 {
return nil
}
return dst.Raw()
// pp.pkt.NetworkLayer().Layer
}
func (pp *pendingPkt) dstPort() uint16 {
return pp.pkt.DstPort
/* dst := pp.pkt.Packet.TransportLayer().TransportFlow().Dst()
if dst.EndpointType() != layers.EndpointTCPPort {
return 0
}
return binary.BigEndian.Uint16(dst.Raw()) */
_, dstp := getPacketTCPPorts(pp.pkt)
return dstp
// return pp.pkt.DstPort
}
func (pp *pendingPkt) accept() {
@ -58,7 +79,8 @@ func (pp *pendingPkt) accept() {
}
func (pp *pendingPkt) drop() {
pp.pkt.Mark = 1
// XXX: This needs to be fixed
// pp.pkt.Mark = 1
pp.pkt.Accept()
}
@ -101,17 +123,21 @@ func (fw *Firewall) policyForPath(path string) *Policy {
return fw.policyMap[path]
}
func (p *Policy) processPacket(pkt *nfqueue.Packet, pinfo *procsnitch.Info) {
func (p *Policy) processPacket(pkt *nfqueue.NFQPacket, pinfo *procsnitch.Info) {
p.lock.Lock()
defer p.lock.Unlock()
name := p.fw.dns.Lookup(pkt.Dst)
dstb := pkt.Packet.NetworkLayer().NetworkFlow().Dst().Raw()
dstip := net.IP(dstb)
name := p.fw.dns.Lookup(dstip)
// name := p.fw.dns.Lookup(pkt.Dst)
if !FirewallConfig.LogRedact {
log.Infof("Lookup(%s): %s", pkt.Dst.String(), name)
log.Infof("Lookup(%s): %s", dstip.String(), name)
}
result := p.rules.filterPacket(pkt, pinfo, name)
switch result {
case FILTER_DENY:
pkt.Mark = 1
// XXX: this needs to be fixed
// pkt.Mark = 1
pkt.Accept()
case FILTER_ALLOW:
pkt.Accept()
@ -228,41 +254,54 @@ func (p *Policy) hasPersistentRules() bool {
return false
}
func printPacket(pkt *nfqueue.Packet, hostname string, pinfo *procsnitch.Info) string {
proto := func() string {
switch pkt.Protocol {
case nfqueue.TCP:
return "TCP"
case nfqueue.UDP:
return "UDP"
func printPacket(pkt *nfqueue.NFQPacket, hostname string, pinfo *procsnitch.Info) string {
proto := "???"
SrcPort, DstPort := uint16(0), uint16(0)
SrcIp, DstIp := getPacketIP4Addrs(pkt)
switch pkt.Packet.TransportLayer().TransportFlow().EndpointType() {
case 4:
proto = "TCP"
case 5:
proto = "UDP"
default:
return "???"
}
}()
}
if proto == "TCP" {
SrcPort, DstPort = getPacketTCPPorts(pkt)
} else if proto == "UDP" {
SrcPort, DstPort = getPacketUDPPorts(pkt)
}
if FirewallConfig.LogRedact {
hostname = STR_REDACTED
}
name := hostname
if name == "" {
name = pkt.Dst.String()
name = DstIp.String()
}
if pinfo == nil {
return fmt.Sprintf("(%s %s:%d -> %s:%d)", proto, pkt.Src, pkt.SrcPort, name, pkt.DstPort)
return fmt.Sprintf("(%s %s:%d -> %s:%d)", proto, SrcIp, SrcPort, name, DstPort)
}
return fmt.Sprintf("%s %s %s:%d -> %s:%d", pinfo.ExePath, proto, pkt.Src, pkt.SrcPort, name, pkt.DstPort)
return fmt.Sprintf("%s %s %s:%d -> %s:%d", pinfo.ExePath, proto, SrcIp, SrcPort, name, DstPort)
}
func (fw *Firewall) filterPacket(pkt *nfqueue.Packet) {
if pkt.Protocol == nfqueue.UDP && pkt.SrcPort == 53 {
pkt.Accept()
fw.dns.processDNS(pkt)
return
func (fw *Firewall) filterPacket(pkt *nfqueue.NFQPacket) {
if pkt.Packet.Layer(layers.LayerTypeUDP) != nil {
srcport, _ := getPacketUDPPorts(pkt)
if srcport == 53 {
pkt.Accept()
fw.dns.processDNS(pkt.Packet)
return
}
}
_, dstip := getPacketIP4Addrs(pkt)
pinfo := findProcessForPacket(pkt)
if pinfo == nil {
log.Warningf("No proc found for %s", printPacket(pkt, fw.dns.Lookup(pkt.Dst), nil))
log.Warningf("No proc found for %s", printPacket(pkt, fw.dns.Lookup(dstip), nil))
pkt.Accept()
return
}
@ -276,7 +315,7 @@ func (fw *Firewall) filterPacket(pkt *nfqueue.Packet) {
}
}
}
log.Debugf("filterPacket [%s] %s", ppath, printPacket(pkt, fw.dns.Lookup(pkt.Dst), nil))
log.Debugf("filterPacket [%s] %s", ppath, printPacket(pkt, fw.dns.Lookup(dstip), nil))
if basicAllowPacket(pkt) {
pkt.Accept()
return
@ -285,20 +324,68 @@ func (fw *Firewall) filterPacket(pkt *nfqueue.Packet) {
policy.processPacket(pkt, pinfo)
}
func findProcessForPacket(pkt *nfqueue.Packet) *procsnitch.Info {
switch pkt.Protocol {
case nfqueue.TCP:
return procsnitch.LookupTCPSocketProcess(pkt.SrcPort, pkt.Dst, pkt.DstPort)
case nfqueue.UDP:
return procsnitch.LookupUDPSocketProcess(pkt.SrcPort)
default:
log.Warningf("Packet has unknown protocol: %d", pkt.Protocol)
return nil
func findProcessForPacket(pkt *nfqueue.NFQPacket) *procsnitch.Info {
_, dstip := getPacketIP4Addrs(pkt)
srcp, dstp := getPacketPorts(pkt)
if pkt.Packet.Layer(layers.LayerTypeTCP) != nil {
return procsnitch.LookupTCPSocketProcess(srcp, dstip, dstp)
} else if pkt.Packet.Layer(layers.LayerTypeUDP) != nil {
return procsnitch.LookupUDPSocketProcess(srcp)
}
log.Warningf("Packet has unknown protocol: %d", pkt.Packet.NetworkLayer().LayerType())
//log.Warningf("Packet has unknown protocol: %d", pkt.Protocol)
return nil
}
func basicAllowPacket(pkt *nfqueue.NFQPacket) bool {
_, dstip := getPacketIP4Addrs(pkt)
return dstip.IsLoopback() ||
dstip.IsLinkLocalMulticast() ||
pkt.Packet.Layer(layers.LayerTypeTCP) == nil
// pkt.Protocol != nfqueue.TCP
}
func basicAllowPacket(pkt *nfqueue.Packet) bool {
return pkt.Dst.IsLoopback() ||
pkt.Dst.IsLinkLocalMulticast() ||
pkt.Protocol != nfqueue.TCP
func getPacketIP4Addrs(pkt *nfqueue.NFQPacket) (net.IP, net.IP) {
ipLayer := pkt.Packet.Layer(layers.LayerTypeIPv4)
if ipLayer == nil {
return net.IP{0,0,0,0}, net.IP{0,0,0,0}
}
ip, _ := ipLayer.(*layers.IPv4)
return ip.SrcIP, ip.DstIP
}
func getPacketTCPPorts(pkt *nfqueue.NFQPacket) (uint16, uint16) {
tcpLayer := pkt.Packet.Layer(layers.LayerTypeTCP)
if tcpLayer == nil {
return 0, 0
}
tcp, _ := tcpLayer.(*layers.TCP)
return uint16(tcp.SrcPort), uint16(tcp.DstPort)
}
func getPacketUDPPorts(pkt *nfqueue.NFQPacket) (uint16, uint16) {
udpLayer := pkt.Packet.Layer(layers.LayerTypeUDP)
if udpLayer == nil {
return 0, 0
}
udp, _ := udpLayer.(*layers.UDP)
return uint16(udp.SrcPort), uint16(udp.DstPort)
}
func getPacketPorts(pkt *nfqueue.NFQPacket) (uint16, uint16) {
s, d := getPacketTCPPorts(pkt)
if s == 0 && d == 0 {
s, d = getPacketUDPPorts(pkt)
}
return s, d
}

@ -11,7 +11,8 @@ import (
"strings"
"unicode"
"github.com/subgraph/fw-daemon/nfqueue"
nfqueue "github.com/subgraph/go-nfnetlink/nfqueue"
// "github.com/subgraph/go-nfnetlink"
"github.com/subgraph/go-procsnitch"
)
@ -82,11 +83,13 @@ func (r *Rule) match(dst net.IP, dstPort uint16, hostname string) bool {
return r.addr == binary.BigEndian.Uint32(dst.To4())
}
func (rl *RuleList) filterPacket(p *nfqueue.Packet, pinfo *procsnitch.Info, hostname string) FilterResult {
return rl.filter(p, p.Dst, p.DstPort, hostname, pinfo)
func (rl *RuleList) filterPacket(p *nfqueue.NFQPacket, pinfo *procsnitch.Info, hostname string) FilterResult {
_, dstip := getPacketIP4Addrs(p)
_, dstp := getPacketPorts(p)
return rl.filter(p, dstip, dstp, hostname, pinfo)
}
func (rl *RuleList) filter(pkt *nfqueue.Packet, dst net.IP, dstPort uint16, hostname string, pinfo *procsnitch.Info) FilterResult {
func (rl *RuleList) filter(pkt *nfqueue.NFQPacket, dst net.IP, dstPort uint16, hostname string, pinfo *procsnitch.Info) FilterResult {
if rl == nil {
return FILTER_PROMPT
}
@ -99,7 +102,9 @@ func (rl *RuleList) filter(pkt *nfqueue.Packet, dst net.IP, dstPort uint16, host
}
srcStr := STR_UNKNOWN
if pkt != nil {
srcStr = fmt.Sprintf("%s:%d", pkt.Src, pkt.SrcPort)
srcip, _ := getPacketIP4Addrs(pkt)
srcp, _ := getPacketPorts(pkt)
srcStr = fmt.Sprintf("%s:%d", srcip, srcp)
}
log.Noticef("%s > %s %s %s -> %s:%d",
r.getString(FirewallConfig.LogRedact),

@ -6,14 +6,14 @@ import (
"regexp"
"sync"
"syscall"
"time"
// "time"
"bufio"
"encoding/json"
"strings"
"github.com/op/go-logging"
"github.com/subgraph/fw-daemon/nfqueue"
nfqueue "github.com/subgraph/go-nfnetlink/nfqueue"
// "github.com/subgraph/go-nfnetlink"
"github.com/subgraph/go-procsnitch"
)
@ -88,20 +88,31 @@ func (fw *Firewall) reloadRules() {
func (fw *Firewall) runFilter() {
q := nfqueue.NewNFQueue(0)
defer q.Destroy()
q.DefaultVerdict = nfqueue.DROP
q.Timeout = 5 * time.Minute
packets := q.Process()
// XXX: need to implement this
// q.DefaultVerdict = nfqueue.DROP
// XXX: need this as well
// q.Timeout = 5 * time.Minute
for {
select {
case pkt := <-packets:
ps, err := q.Open()
if err != nil {
log.Fatal("Error opening NFQueue:", err)
}
defer q.Close()
go func() {
for p := range ps {
if fw.isEnabled() {
fw.filterPacket(pkt)
fw.filterPacket(p)
} else {
pkt.Accept()
p.Accept()
}
}
}()
for {
select {
case <-fw.reloadRulesChan:
fw.loadRules()
case <-fw.stopChan:

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