Adding to nat expression additional parameters (#59)

* Change in dnat logic to cover all combinations

Signed-off-by: Serguei Bezverkhi <sbezverk@cisco.com>

* Add parameter to cover all possible nat combinations

Signed-off-by: Serguei Bezverkhi <sbezverk@cisco.com>
This commit is contained in:
Serguei Bezverkhi 2019-09-06 02:28:27 -04:00 committed by Michael Stapelberg
parent a0a4b3333d
commit 5d14089d2e
1 changed files with 57 additions and 6 deletions

View File

@ -15,7 +15,7 @@
package expr
import (
"fmt"
"encoding/binary"
"github.com/google/nftables/binaryutil"
"github.com/mdlayher/netlink"
@ -34,8 +34,12 @@ type NAT struct {
Type NATType
Family uint32 // TODO: typed const
RegAddrMin uint32
RegAddrMax uint32
RegProtoMin uint32
RegProtoMax uint32
Random bool
FullyRandom bool
Persistent bool
}
// |00048|N-|00001| |len |flags| type|
@ -55,12 +59,33 @@ func (e *NAT) marshal() ([]byte, error) {
attrs := []netlink.Attribute{
{Type: unix.NFTA_NAT_TYPE, Data: binaryutil.BigEndian.PutUint32(uint32(e.Type))},
{Type: unix.NFTA_NAT_FAMILY, Data: binaryutil.BigEndian.PutUint32(e.Family)},
{Type: unix.NFTA_NAT_REG_ADDR_MIN, Data: binaryutil.BigEndian.PutUint32(e.RegAddrMin)},
{Type: unix.NFTA_NAT_REG_PROTO_MIN, Data: binaryutil.BigEndian.PutUint32(e.RegProtoMin)},
}
if e.RegProtoMax > 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_REG_PROTO_MAX, Data: binaryutil.BigEndian.PutUint32(e.RegProtoMax)})
if e.RegAddrMin != 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_REG_ADDR_MIN, Data: binaryutil.BigEndian.PutUint32(e.RegAddrMin)})
if e.RegAddrMax != 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_REG_ADDR_MAX, Data: binaryutil.BigEndian.PutUint32(e.RegAddrMax)})
}
}
if e.RegProtoMin != 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_REG_PROTO_MIN, Data: binaryutil.BigEndian.PutUint32(e.RegProtoMin)})
if e.RegProtoMax != 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_REG_PROTO_MAX, Data: binaryutil.BigEndian.PutUint32(e.RegProtoMax)})
}
}
flags := uint32(0)
if e.Random {
flags |= NF_NAT_RANGE_PROTO_RANDOM
}
if e.FullyRandom {
flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY
}
if e.Persistent {
flags |= NF_NAT_RANGE_PERSISTENT
}
if flags != 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NFTA_NAT_FLAGS, Data: binaryutil.BigEndian.PutUint32(flags)})
}
data, err := netlink.MarshalAttributes(attrs)
if err != nil {
return nil, err
@ -72,5 +97,31 @@ func (e *NAT) marshal() ([]byte, error) {
}
func (e *NAT) unmarshal(data []byte) error {
return fmt.Errorf("not yet implemented")
ad, err := netlink.NewAttributeDecoder(data)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
for ad.Next() {
switch ad.Type() {
case unix.NFTA_NAT_TYPE:
e.Type = NATType(ad.Uint32())
case unix.NFTA_NAT_FAMILY:
e.Family = ad.Uint32()
case unix.NFTA_NAT_REG_ADDR_MIN:
e.RegAddrMin = ad.Uint32()
case unix.NFTA_NAT_REG_ADDR_MAX:
e.RegAddrMax = ad.Uint32()
case unix.NFTA_NAT_REG_PROTO_MIN:
e.RegProtoMin = ad.Uint32()
case unix.NFTA_NAT_REG_PROTO_MAX:
e.RegProtoMax = ad.Uint32()
case unix.NFTA_NAT_FLAGS:
flags := ad.Uint32()
e.Persistent = (flags & NF_NAT_RANGE_PERSISTENT) != 0
e.Random = (flags & NF_NAT_RANGE_PROTO_RANDOM) != 0
e.FullyRandom = (flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY) != 0
}
}
return ad.Err()
}