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tcp.go
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tcp.go
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// +build linux
package tcp
import (
"context"
"crypto/tls"
"encoding/hex"
"errors"
"fmt"
"io"
"net"
"os"
"strconv"
"sync"
"syscall"
"unsafe"
"go.uber.org/zap"
"github.com/aporeto-inc/netlink-go/conntrack"
"github.com/aporeto-inc/trireme-lib/collector"
"github.com/aporeto-inc/trireme-lib/common"
"github.com/aporeto-inc/trireme-lib/controller/constants"
"github.com/aporeto-inc/trireme-lib/controller/internal/enforcer/constants"
"github.com/aporeto-inc/trireme-lib/controller/internal/enforcer/nfqdatapath/tokenaccessor"
"github.com/aporeto-inc/trireme-lib/controller/internal/portset"
"github.com/aporeto-inc/trireme-lib/controller/pkg/connection"
"github.com/aporeto-inc/trireme-lib/controller/pkg/fqconfig"
"github.com/aporeto-inc/trireme-lib/controller/pkg/pucontext"
"github.com/aporeto-inc/trireme-lib/controller/pkg/secrets"
"github.com/aporeto-inc/trireme-lib/policy"
"github.com/aporeto-inc/trireme-lib/utils/cache"
)
const (
sockOptOriginalDst = 80
proxyMarkInt = 0x40 //Duplicated from supervisor/iptablesctrl refer to it
)
type secretsPEM interface {
AuthPEM() []byte
TransmittedPEM() []byte
EncodingPEM() []byte
}
// Proxy maintains state for proxies connections from listen to backend.
type Proxy struct {
// Listen specifies port to listen on.
Listen string
// Backend address of the backend
Backend string
// certPath certificate path
certPath string
keyPath string
wg sync.WaitGroup
// Forward specifies if we should forward this connection.
Forward bool
// Encrypt specifies if this connection encrypted.
Encrypt bool
mutualAuthorization bool
tokenaccessor tokenaccessor.TokenAccessor
collector collector.EventCollector
puFromContextID cache.DataStore
socketListeners *cache.Cache
// List of local IP's
IPList []string
tlsCertificate *tls.Certificate
certLock sync.Mutex
}
// proxyFlowProperties is a struct used to pass flow information up
type proxyFlowProperties struct {
SourceIP net.IP
DestIP net.IP
SourcePort uint16
DestPort uint16
}
type socketListenerEntry struct {
listen net.Listener
port string
}
type sockaddr struct {
family uint16
data [14]byte
}
// NewProxy creates a new instance of proxy reate a new instance of Proxy
func NewProxy(listen string, forward bool, encrypt bool, tp tokenaccessor.TokenAccessor, c collector.EventCollector, puFromContextID cache.DataStore, mutualAuthorization bool, secret secrets.Secrets) *Proxy {
ifaces, _ := net.Interfaces()
iplist := []string{}
for _, intf := range ifaces {
addrs, _ := intf.Addrs()
for _, addr := range addrs {
ip, _, _ := net.ParseCIDR(addr.String())
if ip.To4() != nil {
iplist = append(iplist, ip.String())
}
}
}
pkier := secret.(secretsPEM)
var certificate tls.Certificate
var err error
if secret.Type() != secrets.PSKType {
certificate, err = tls.X509KeyPair(pkier.TransmittedPEM(), pkier.EncodingPEM())
if err != nil {
return nil
}
}
return &Proxy{
Forward: forward,
Encrypt: encrypt,
wg: sync.WaitGroup{},
mutualAuthorization: mutualAuthorization,
collector: c,
tokenaccessor: tp,
puFromContextID: puFromContextID,
socketListeners: cache.NewCache("socketlisterner"),
IPList: iplist,
certLock: sync.Mutex{},
tlsCertificate: &certificate,
}
}
// Enforce implements enforcer.Enforcer interface
func (p *Proxy) Enforce(contextID string, puInfo *policy.PUInfo) error {
_, err := p.puFromContextID.Get(contextID)
if err != nil {
//Start proxy
errChan := make(chan error, 1)
port := puInfo.Runtime.Options().ProxyPort
go p.StartListener(contextID, errChan, port)
err, closed := <-errChan
if closed {
return nil
}
if err != nil {
return err
}
}
// Nothing required for the update case we will use the parent datapath structures to store state about PU
return nil
}
// StartListener implements enforcer.Enforcer interface
func (p *Proxy) StartListener(contextID string, reterr chan error, port string) {
var err error
var listener net.Listener
port = ":" + port
if p.Forward || !p.Encrypt {
if listener, err = net.Listen("tcp", port); err != nil {
zap.L().Warn("Failed to Bind", zap.Error(err))
reterr <- nil
return
}
} else {
config, err := p.loadTLS()
if err != nil {
reterr <- err
}
if listener, err = tls.Listen("tcp", port, config); err != nil {
reterr <- err
}
}
//At this point we are done initing lets close channel
close(reterr)
p.socketListeners.AddOrUpdate(contextID, &socketListenerEntry{
listen: listener,
port: port,
})
for {
if conn, err := listener.Accept(); err == nil {
filehdl, _ := conn.(*net.TCPConn).File()
err = syscall.SetsockoptInt(int(filehdl.Fd()), syscall.SOL_SOCKET, syscall.SO_MARK, proxyMarkInt)
if err != nil {
zap.L().Error(err.Error())
}
p.wg.Add(1)
go func() {
defer p.wg.Done()
p.handle(conn, contextID)
if connErr := conn.Close(); connErr != nil {
zap.L().Error("Failed to close DownConn", zap.String("ContextID", contextID))
}
}()
} else {
return
}
}
}
// Unenforce implements enforcer.Enforcer interface
func (p *Proxy) Unenforce(contextID string) error {
entry, err := p.socketListeners.Get(contextID)
if err == nil {
if cerr := entry.(*socketListenerEntry).listen.Close(); cerr != nil {
zap.L().Error("Close failed for downconn", zap.String("ContextID", contextID))
}
}
if err = p.socketListeners.Remove(contextID); err != nil {
zap.L().Error("Cannot remove Socket Listener", zap.Error(err), zap.String("ContextID", contextID))
}
return nil
}
// GetFilterQueue is a stub for TCP proxy
func (p *Proxy) GetFilterQueue() *fqconfig.FilterQueue {
return nil
}
// GetPortSetInstance returns nil for the proxy
func (p *Proxy) GetPortSetInstance() portset.PortSet {
return nil
}
// Run is a stub for TCP proxy
func (p *Proxy) Run(ctx context.Context) error {
go func() {
<-ctx.Done()
p.wg.Wait()
}()
return nil
}
// UpdateSecrets updates the secrets of running enforcers managed by trireme. Remote enforcers will get the secret updates with the next policy push
func (p *Proxy) UpdateSecrets(secret secrets.Secrets) error {
pkier := secret.(secretsPEM)
var certificate tls.Certificate
var err error
if secret.Type() != secrets.PSKType {
if certificate, err = tls.X509KeyPair(pkier.TransmittedPEM(), pkier.EncodingPEM()); err != nil {
return fmt.Errorf("Cannot extract cert and key from secrets %s", err)
}
p.certLock.Lock()
p.tlsCertificate = &certificate
p.certLock.Unlock()
}
return p.tokenaccessor.SetToken(p.tokenaccessor.GetTokenServerID(), p.tokenaccessor.GetTokenValidity(), secret)
}
// loadTLS configuration - static files for the time being
func (p *Proxy) loadTLS() (*tls.Config, error) {
cert, err := tls.LoadX509KeyPair(p.certPath, p.keyPath)
if err != nil {
return nil, err
}
return &tls.Config{Certificates: []tls.Certificate{cert}, InsecureSkipVerify: true}, nil
}
// handle handles a connection
func (p *Proxy) handle(upConn net.Conn, contextID string) {
var err error
var ip []byte
var port uint16
defer func() {
if err = upConn.Close(); err != nil {
zap.L().Error("Failed to close UpConn", zap.Error(err))
}
}()
//backend := p.Backend
if p.Forward {
ip, port, err = getOriginalDestination(upConn)
if err != nil {
return
}
}
downConn, err := p.downConnection(ip, port)
if err != nil {
if downConn > 0 {
if err = syscall.Close(downConn); err != nil {
zap.L().Error("Cannot close DownConn", zap.String("ContextID", contextID), zap.Error(err))
}
}
return
}
defer func() {
if err = syscall.Close(downConn); err != nil {
zap.L().Error("Unable to close DownConn", zap.Error(err))
}
}()
var isEncrypted bool
// Now let us handle the state machine for the down connection
if isEncrypted, err = p.CompleteEndPointAuthorization(string(ip), port, upConn, downConn, contextID); err != nil {
zap.L().Error("Error on Authorization", zap.Error(err))
return
}
if !isEncrypted {
if err = Pipe(upConn.(*net.TCPConn), downConn); err != nil {
fmt.Printf("pipe failed: %s", err)
}
} else {
// Hand off encryption to service processor for proxied traffic
if p.tlsCertificate == nil {
zap.L().Error("Cannot do Encrypted proxy connection without certifcates")
}
if err = p.handleEncryptedData(upConn, downConn); err != nil {
zap.L().Error("Failed to setup encrypted connection", zap.Error(err))
}
}
}
func islocalIP(backendip string) bool {
ifaces, _ := net.Interfaces()
iplist := []string{}
for _, intf := range ifaces {
addrs, _ := intf.Addrs()
for _, addr := range addrs {
ip, _, _ := net.ParseCIDR(addr.String())
if ip.To4() != nil {
iplist = append(iplist, ip.String())
}
}
}
for _, ip := range iplist {
fmt.Println("IPS", ip, net.IPv4(backendip[0], backendip[1], backendip[2], backendip[3]).String())
if ip == net.IPv4(backendip[0], backendip[1], backendip[2], backendip[3]).String() {
return true
}
}
return false
}
func (p *Proxy) startEncryptedClientDataPath(fd int, conn io.ReadWriter) error {
tlsFs := os.NewFile(uintptr(fd), "TLSSOCK")
if tlsFs == nil {
return fmt.Errorf("Cannot convert to Fs")
}
netConn, _ := net.FileConn(tlsFs)
tlsConn := tls.Client(netConn, &tls.Config{
InsecureSkipVerify: true,
})
if tlsConn == nil {
return fmt.Errorf("Cannot convert to tls Connection")
}
if err := tlsConn.Handshake(); err != nil {
return err
}
var wg sync.WaitGroup
wg.Add(2)
go func() {
defer wg.Done()
b := make([]byte, 4*1024)
for {
if n, err := conn.Read(b); err == nil {
if _, err = tlsConn.Write(b[:n]); err != nil {
return
}
continue
} else {
return
}
}
}()
go func() {
defer wg.Done()
b := make([]byte, 4*1024)
for {
if n, err := tlsConn.Read(b); err == nil {
if _, err = conn.Write(b[:n]); err != nil {
return
}
continue
} else {
return
}
}
}()
wg.Wait()
return nil
}
func (p *Proxy) startEncryptedServerDataPath(fd int, conn net.Conn) error {
p.certLock.Lock()
certs := []tls.Certificate{*p.tlsCertificate}
p.certLock.Unlock()
tlsConn := tls.Server(conn, &tls.Config{
Certificates: certs,
})
if err := tlsConn.Handshake(); err != nil {
return err
}
fs := os.NewFile(uintptr(fd), "NONTLSSOCK")
netConn, _ := net.FileConn(fs)
var wg sync.WaitGroup
wg.Add(2)
go func() {
defer wg.Done()
b := make([]byte, 1024)
for {
n, err := tlsConn.Read(b)
if err != nil {
return
}
if _, err = netConn.Write(b[:n]); err != nil {
return
}
}
}()
go func() {
defer wg.Done()
b := make([]byte, 1024)
for {
n, err := netConn.Read(b)
if err != nil {
return
}
if _, err = tlsConn.Write(b[:n]); err != nil {
return
}
}
}()
wg.Wait()
return nil
}
func (p *Proxy) handleEncryptedData(upConn net.Conn, downConn int) error {
// backendip := upConn.RemoteAddr().Network()
ip, _, err := getOriginalDestination(upConn)
if err != nil {
return err
}
if islocalIP(string(ip)) {
return p.startEncryptedServerDataPath(downConn, upConn)
}
return p.startEncryptedClientDataPath(downConn, upConn)
}
func getsockopt(s int, level int, name int, val uintptr, vallen *uint32) (err error) {
_, _, e1 := syscall.Syscall6(syscall.SYS_GETSOCKOPT, uintptr(s), uintptr(level), uintptr(name), uintptr(val), uintptr(unsafe.Pointer(vallen)), 0)
if e1 != 0 {
err = e1
}
return
}
// getOriginalDestination -- Func to get original destination of redirected packet. Used to figure out backend destination
func getOriginalDestination(conn net.Conn) ([]byte, uint16, error) {
var addr sockaddr
size := uint32(unsafe.Sizeof(addr))
inFile, err := conn.(*net.TCPConn).File()
if err != nil {
return []byte{}, 0, err
}
err = getsockopt(int(inFile.Fd()), syscall.SOL_IP, sockOptOriginalDst, uintptr(unsafe.Pointer(&addr)), &size)
if err != nil {
return []byte{}, 0, err
}
var ip net.IP
if addr.family != syscall.AF_INET {
return []byte{}, 0, errors.New("invalid address family")
}
ip = addr.data[2:6]
port := uint16(int(addr.data[0])<<8 + int(addr.data[1]))
return ip, port, nil
}
func (p *Proxy) puContextFromContextID(contextID string) (*pucontext.PUContext, error) {
ctx, err := p.puFromContextID.Get(contextID)
if err != nil {
return nil, fmt.Errorf("Context not found %s", contextID)
}
puContext, ok := ctx.(*pucontext.PUContext)
if !ok {
return nil, fmt.Errorf("Context not converted %s", contextID)
}
return puContext, nil
}
// Initiate the downstream connection
func (p *Proxy) downConnection(ip []byte, port uint16) (int, error) {
var err error
fd, err := syscall.Socket(syscall.AF_INET, syscall.SOCK_STREAM, 0)
if err != nil {
zap.L().Error("Socket create failed", zap.String("Error", err.Error()))
}
err = syscall.SetsockoptInt(fd, syscall.SOL_SOCKET, syscall.SO_MARK, proxyMarkInt)
if err != nil {
zap.L().Error("Sockopt failed", zap.String("Error", err.Error()))
}
address := &syscall.SockaddrInet4{
Port: int(port),
}
copy(address.Addr[:], ip)
if p.Encrypt && p.Forward {
// config, err := p.loadTLS()
// if err != nil {
// return nil, err
// }
// downConn, err = tls.Dial("tcp", backend, config)
// if err != nil {
// return nil, err
// }
} else {
err = syscall.Connect(fd, address)
if err != nil {
zap.L().Error("Connect Error", zap.String("Connect Error", err.Error()))
return fd, err
}
addr, _ := syscall.Getpeername(fd)
remote := addr.(*syscall.SockaddrInet4)
addr, _ = syscall.Getsockname(fd)
local := addr.(*syscall.SockaddrInet4)
conntrackHdl := conntrack.NewHandle()
if connterror := conntrackHdl.ConntrackTableUpdateMark(net.IPv4(local.Addr[0], local.Addr[1], local.Addr[2], local.Addr[3]).String(),
net.IPv4(remote.Addr[0], remote.Addr[1], remote.Addr[2], remote.Addr[3]).String(),
syscall.IPPROTO_TCP,
uint16(local.Port),
uint16(remote.Port),
constants.DefaultConnMark,
); connterror != nil {
zap.L().Error("Unable to mark flow")
}
}
return fd, nil
}
// CompleteEndPointAuthorization -- Aporeto Handshake on top of a completed connection
// We will define states here equivalent to SYN_SENT AND SYN_RECEIVED
func (p *Proxy) CompleteEndPointAuthorization(backendip string, backendport uint16, upConn net.Conn, downConn int, contextID string) (bool, error) {
puContext, err := p.puContextFromContextID(contextID)
if err != nil {
return false, err
}
if puContext.Type() == common.LinuxProcessPU {
//Are we client or server proxy
if len(puContext.Ports()) > 0 && puContext.Ports()[0] != "0" {
return p.StartServerAuthStateMachine(backendip, backendport, upConn, downConn, contextID)
}
//We are client no advertised port
return p.StartClientAuthStateMachine(backendip, backendport, upConn, downConn, contextID)
}
//Assumption within a container two applications talking to each other won't be proxied.
//If backend ip is non local we are client else we are server
islocalIP := func() bool {
for _, ip := range p.IPList {
if ip == backendip {
return true
}
}
return false
}()
if islocalIP {
return p.StartServerAuthStateMachine(backendip, backendport, upConn, downConn, contextID)
}
return p.StartClientAuthStateMachine(backendip, backendport, upConn, downConn, contextID)
}
//StartClientAuthStateMachine -- Starts the aporeto handshake for client application
func (p *Proxy) StartClientAuthStateMachine(backendip string, backendport uint16, upConn net.Conn, downConn int, contextID string) (bool, error) {
// We are running on top of TCP nothing should be lost or come out of order makes the state machines easy....
puContext, err := p.puContextFromContextID(contextID)
if err != nil {
return false, err
}
isEncrypted := false
conn := connection.NewProxyConnection()
toAddr, _ := syscall.Getpeername(downConn)
localaddr, _ := syscall.Getsockname(downConn)
localinet4ip, _ := localaddr.(*syscall.SockaddrInet4)
remoteinet4ip, _ := toAddr.(*syscall.SockaddrInet4)
flowProperties := &proxyFlowProperties{
SourceIP: net.IPv4(localinet4ip.Addr[0], localinet4ip.Addr[1], localinet4ip.Addr[2], localinet4ip.Addr[3]),
DestIP: net.IPv4(remoteinet4ip.Addr[0], remoteinet4ip.Addr[1], remoteinet4ip.Addr[2], remoteinet4ip.Addr[3]),
SourcePort: uint16(localinet4ip.Port),
DestPort: uint16(remoteinet4ip.Port),
}
L:
for conn.GetState() == connection.ClientTokenSend {
msg := make([]byte, 1024)
for {
switch conn.GetState() {
case connection.ClientTokenSend:
if p.tokenaccessor == nil {
return isEncrypted, fmt.Errorf("NIL TOKENAccessor")
}
token, err := p.tokenaccessor.CreateSynPacketToken(puContext, &conn.Auth)
if err != nil {
return isEncrypted, fmt.Errorf("unable to create syn token: %s", err)
}
zap.L().Error("Sending token", zap.String("Token", hex.Dump(token)))
if err := syscall.Sendto(downConn, token, 0, toAddr); err != nil {
return isEncrypted, fmt.Errorf("unable to send syn: %s", err)
}
conn.SetState(connection.ClientPeerTokenReceive)
case connection.ClientPeerTokenReceive:
n, _, err := syscall.Recvfrom(downConn, msg, 0)
if err != nil {
return isEncrypted, fmt.Errorf("unable to recvfrom: %s", err)
}
msg = msg[:n]
claims, err := p.tokenaccessor.ParsePacketToken(&conn.Auth, msg)
if err != nil || claims == nil {
p.reportRejectedFlow(flowProperties, conn, collector.DefaultEndPoint, puContext.ManagementID(), puContext, collector.InvalidToken, nil, nil)
return false, fmt.Errorf("peer token reject because of bad claims: error: %s, claims: %v", err, claims)
}
if p.mutualAuthorization {
report, packet := puContext.SearchTxtRules(claims.T, !p.mutualAuthorization)
if packet.Action.Rejected() {
p.reportRejectedFlow(flowProperties, conn, puContext.ManagementID(), conn.Auth.RemoteContextID, puContext, collector.PolicyDrop, report, packet)
return isEncrypted, errors.New("dropping because of reject rule on transmitter")
}
if packet.Action.Encrypted() {
isEncrypted = true
}
}
conn.SetState(connection.ClientSendSignedPair)
case connection.ClientSendSignedPair:
token, err := p.tokenaccessor.CreateAckPacketToken(puContext, &conn.Auth)
if err != nil {
return isEncrypted, fmt.Errorf("unable to create ack token: %s", err)
}
if err := syscall.Sendto(downConn, token, 0, toAddr); err != nil {
return isEncrypted, fmt.Errorf("unable to send ack: %s", err)
}
break L
}
}
}
return isEncrypted, nil
}
// StartServerAuthStateMachine -- Start the aporeto handshake for a server application
func (p *Proxy) StartServerAuthStateMachine(backendip string, backendport uint16, upConn io.ReadWriter, downConn int, contextID string) (bool, error) {
puContext, err := p.puContextFromContextID(contextID)
if err != nil {
return false, err
}
isEncrypted := false
toAddr, _ := syscall.Getpeername(downConn)
localaddr, _ := syscall.Getsockname(downConn)
localinet4ip, _ := localaddr.(*syscall.SockaddrInet4)
remoteinet4ip, _ := toAddr.(*syscall.SockaddrInet4)
flowProperties := &proxyFlowProperties{
SourceIP: net.IPv4(localinet4ip.Addr[0], localinet4ip.Addr[1], localinet4ip.Addr[2], localinet4ip.Addr[3]),
DestIP: net.IPv4(remoteinet4ip.Addr[0], remoteinet4ip.Addr[1], remoteinet4ip.Addr[2], remoteinet4ip.Addr[3]),
SourcePort: uint16(localinet4ip.Port),
DestPort: uint16(remoteinet4ip.Port),
}
conn := connection.NewProxyConnection()
conn.SetState(connection.ServerReceivePeerToken)
E:
for conn.GetState() == connection.ServerReceivePeerToken {
for {
msg := []byte{}
switch conn.GetState() {
case connection.ServerReceivePeerToken:
for {
data := make([]byte, 1024)
n, err := upConn.Read(data)
if n < 1024 || err == nil {
msg = append(msg, data[:n]...)
break
}
if err != nil {
return isEncrypted, err
}
msg = append(msg, data[:n]...)
}
claims, err := p.tokenaccessor.ParsePacketToken(&conn.Auth, msg)
if err != nil || claims == nil {
p.reportRejectedFlow(flowProperties, conn, collector.DefaultEndPoint, puContext.ManagementID(), puContext, collector.InvalidToken, nil, nil)
return isEncrypted, fmt.Errorf("reported rejected flow due to invalid token: %s", err)
}
claims.T.AppendKeyValue(enforcerconstants.PortNumberLabelString, strconv.Itoa(int(backendport)))
report, packet := puContext.SearchRcvRules(claims.T)
if packet.Action.Rejected() {
p.reportRejectedFlow(flowProperties, conn, collector.DefaultEndPoint, puContext.ManagementID(), puContext, collector.PolicyDrop, report, packet)
return isEncrypted, fmt.Errorf("connection dropped by policy %s: %s", packet.PolicyID, err)
}
if packet.Action.Encrypted() {
isEncrypted = true
}
conn.ReportFlowPolicy = report
conn.PacketFlowPolicy = packet
conn.SetState(connection.ServerSendToken)
case connection.ServerSendToken:
claims, err := p.tokenaccessor.CreateSynAckPacketToken(puContext, &conn.Auth)
if err != nil {
return isEncrypted, fmt.Errorf("unable to create synack token: %s", err)
}
synackn, err := upConn.Write(claims)
if err != nil {
zap.L().Error("Failed to write", zap.Error(err))
}
zap.L().Debug("Returned SynACK Token size", zap.Int("Token Length", synackn))
conn.SetState(connection.ServerAuthenticatePair)
case connection.ServerAuthenticatePair:
for {
data := make([]byte, 1024)
n, err := upConn.Read(data)
if n < 1024 || err == nil {
msg = append(msg, data[:n]...)
break
}
if err != nil {
return isEncrypted, err
}
msg = append(msg, data[:n]...)
}
if _, err := p.tokenaccessor.ParseAckToken(&conn.Auth, msg); err != nil {
p.reportRejectedFlow(flowProperties, conn, collector.DefaultEndPoint, puContext.ManagementID(), puContext, collector.InvalidFormat, nil, nil)
return isEncrypted, fmt.Errorf("ack packet dropped because signature validation failed %s", err)
}
break E
}
}
}
p.reportAcceptedFlow(flowProperties, conn, conn.Auth.RemoteContextID, puContext.ManagementID(), puContext, conn.ReportFlowPolicy, conn.PacketFlowPolicy)
return isEncrypted, nil
}
func (p *Proxy) reportFlow(flowproperties *proxyFlowProperties, conn *connection.ProxyConnection, sourceID string, destID string, context *pucontext.PUContext, mode string, report *policy.FlowPolicy, packet *policy.FlowPolicy) {
c := &collector.FlowRecord{
ContextID: context.ID(),
Source: &collector.EndPoint{
ID: sourceID,
IP: flowproperties.SourceIP.String(),
Port: flowproperties.SourcePort,
Type: collector.PU,
},
Destination: &collector.EndPoint{
ID: destID,
IP: flowproperties.DestIP.String(),
Port: flowproperties.DestPort,
Type: collector.PU,
},
Tags: context.Annotations(),
Action: report.Action,
DropReason: mode,
PolicyID: report.PolicyID,
}
if report.ObserveAction.Observed() {
c.ObservedAction = packet.Action
c.ObservedPolicyID = packet.PolicyID
}
p.collector.CollectFlowEvent(c)
}
func (p *Proxy) reportAcceptedFlow(flowproperties *proxyFlowProperties, conn *connection.ProxyConnection, sourceID string, destID string, context *pucontext.PUContext, report *policy.FlowPolicy, packet *policy.FlowPolicy) {
p.reportFlow(flowproperties, conn, sourceID, destID, context, "N/A", report, packet)
}
func (p *Proxy) reportRejectedFlow(flowproperties *proxyFlowProperties, conn *connection.ProxyConnection, sourceID string, destID string, context *pucontext.PUContext, mode string, report *policy.FlowPolicy, packet *policy.FlowPolicy) {
if report == nil {
report = &policy.FlowPolicy{
Action: policy.Reject,
PolicyID: "",
}
}
if packet == nil {
packet = report
}
p.reportFlow(flowproperties, conn, sourceID, destID, context, mode, report, packet)
}