clean up nft rules

This commit is contained in:
Matthew R. Kasun 2022-09-02 11:01:19 -04:00
parent 16959f395a
commit ecc9ef5aac
2 changed files with 36 additions and 31 deletions

View file

@ -43,13 +43,13 @@ func CreateEgressGateway(gateway models.EgressGatewayRequest) (models.Node, erro
switch node.FirewallInUse {
case models.FIREWALL_NFTABLES:
// nftables only supported on Linux
// assumes chains eg FORWARD and POSTROUTING already exist
// assumes chains eg FORWARD and postrouting already exist
logger.Log(3, "creating egress gateway nftables is present")
// down commands don't remove as removal of the rules leaves an empty chain while
// removing the chain with rules in it would remove all rules in that section (not safe
// if there are remaining rules on the host that need to stay). In practice the chain is removed
// when non-empty even though the removal of a non-empty chain should not be possible per nftables wiki.
postUpCmd, postDownCmd = firewallNFTCommandsCreateEgress(node.Interface, gateway.Interface, gateway.Ranges, node.EgressGatewayNatEnabled)
postUpCmd, postDownCmd = firewallNFTCommandsCreateEgress(node.Interface, gateway.Interface, gateway.Ranges, node.EgressGatewayNatEnabled, ipv4, ipv6)
default: // iptables assumed
logger.Log(3, "creating egress gateway nftables is not present")
@ -130,7 +130,10 @@ func DeleteEgressGateway(network, nodeid string) (models.Node, error) {
// needed in case we don't preserve a gateway (i.e., no ingress to preserve)
node.PostUp = ""
node.PostDown = ""
cidrs := []string{}
cidrs = append(cidrs, node.IngressGatewayRange)
cidrs = append(cidrs, node.IngressGatewayRange6)
ipv4, ipv6 := getNetworkProtocols(cidrs)
logger.Log(3, "deleting egress gateway firewall in use is '", node.FirewallInUse, "'")
if node.IsIngressGateway == "yes" { // check if node is still an ingress gateway before completely deleting postdown/up rules
// still have an ingress gateway so preserve it
@ -138,12 +141,12 @@ func DeleteEgressGateway(network, nodeid string) (models.Node, error) {
switch node.FirewallInUse {
case models.FIREWALL_NFTABLES:
// nftables only supported on Linux
// assumes chains eg FORWARD and POSTROUTING already exist
// assumes chains eg FORWARD and postrouting already exist
logger.Log(3, "deleting egress gateway nftables is present")
node.PostUp, node.PostDown = firewallNFTCommandsCreateIngress(node.Interface)
default:
logger.Log(3, "deleting egress gateway nftables is not present")
node.PostUp, node.PostDown = firewallIPTablesCommandsCreateIngress(node.Interface)
node.PostUp, node.PostDown = firewallIPTablesCommandsCreateIngress(node.Interface, ipv4, ipv6)
}
}
// no need to preserve ingress gateway on FreeBSD as ingress is not supported on that OS
@ -181,14 +184,17 @@ func CreateIngressGateway(netid string, nodeid string) (models.Node, error) {
return models.Node{}, err
}
node.IsIngressGateway = "yes"
node.IngressGatewayRange = append(node.IngressGatewayRange, network.AddressRange)
node.IngressGatewayRange = append(node.IngressGatewayRange, network.AddressRange6)
ipv4, ipv6 = getNetworkProtocols(node.IngressGatewayRange)
cidrs := []string{}
cidrs = append(cidrs, network.AddressRange)
cidrs = append(cidrs, network.AddressRange6)
node.IngressGatewayRange = network.AddressRange
node.IngressGatewayRange6 = network.AddressRange6
ipv4, ipv6 := getNetworkProtocols(cidrs)
logger.Log(3, "creating ingress gateway firewall in use is '", node.FirewallInUse, "'")
switch node.FirewallInUse {
case models.FIREWALL_NFTABLES:
// nftables only supported on Linux
// assumes chains eg FORWARD and POSTROUTING already exist
// assumes chains eg FORWARD and postrouting already exist
logger.Log(3, "creating ingress gateway nftables is present")
postUpCmd, postDownCmd = firewallNFTCommandsCreateIngress(node.Interface)
default:
@ -295,8 +301,8 @@ func firewallNFTCommandsCreateIngress(networkInterface string) (string, string)
postUp += "nft add rule ip filter FORWARD iifname " + networkInterface + " counter accept ; "
postUp += "nft add rule ip filter FORWARD oifname " + networkInterface + " counter accept ; "
postUp += "nft add table nat ; "
postUp += "nft add chain nat POSTROUTING ; "
postUp += "nft add rule ip nat POSTROUTING oifname " + networkInterface + " counter masquerade"
postUp += "nft add chain nat postrouting ; "
postUp += "nft add rule ip nat postrouting oifname " + networkInterface + " counter masquerade"
// doesn't remove potentially empty tables or chains
postDown := "nft flush table filter ; "
@ -336,24 +342,19 @@ func firewallNFTCommandsCreateEgress(networkInterface string, gatewayInterface s
if ipv6 {
postUp += "nft add table ip6 filter ; "
postUp += "nft add chain ip6 filter forward ; "
postUp += "nft add rule filter forward ct state related,established accept ; "
postUp += "nft add rule ip6 filter forward ct state related,established accept ; "
postUp += "nft add rule ip6 filter forward iifname " + networkInterface + " accept ; "
postUp += "nft add rule ip6 filter forward oifname " + networkInterface + " accept ; "
postUp += "nft add table ip6 nat ; "
postUp += "nft 'add chain ip6 nat prerouting { type nat hook prerouting priority 0 ;}' ; "
postUp += "nft 'add chain ip6 nat postrouting { type nat hook postrouting priority 0 ;}' ; "
for _, networkCIDR := range gatewayranges {
postUp += "nft add rule ip6 nat postrouting iifname " + networkInterface + " oifname " + gatewayInterface + " ip saddr " + networkCIDR + " masquerade ; "
}
postDown += "nft flush table filter ; "
postDown += "nft flush table ip6 filter ; "
if egressNatEnabled == "yes" {
postUp += "nft add table ip6 nat ; "
postUp += "nft add chain nat postrouting ; "
postUp += "nft add rule ip nat postrouting oifname " + gatewayInterface + " masquerade ; "
postUp += "nft 'add chain ip6 nat prerouting { type nat hook prerouting priority 0 ;}' ; "
postUp += "nft 'add chain ip6 nat postrouting { type nat hook postrouting priority 0 ;}' ; "
postUp += "nft add rule ip6 nat postrouting oifname " + gatewayInterface + " masquerade ; "
postDown += "nft flush table nat ; "
postDown += "nft flush table ip6 nat ; "
}
}
@ -368,23 +369,23 @@ func firewallIPTablesCommandsCreateIngress(networkInterface string, ipv4, ipv6 b
// spacing around ; is important for later parsing of postup/postdown in wireguard/common.go
postUp += "iptables -A FORWARD -i " + networkInterface + " -j ACCEPT ; "
postUp += "iptables -A FORWARD -o " + networkInterface + " -j ACCEPT ; "
postUp += "iptables -t nat -A POSTROUTING -o " + networkInterface + " -j MASQUERADE"
postUp += "iptables -t nat -A postrouting -o " + networkInterface + " -j masquerade"
// doesn't remove potentially empty tables or chains
postDown += "iptables -D FORWARD -i " + networkInterface + " -j ACCEPT ; "
postDown += "iptables -D FORWARD -o " + networkInterface + " -j ACCEPT ; "
postDown += "iptables -t nat -D POSTROUTING -o " + networkInterface + " -j MASQUERADE"
postDown += "iptables -t nat -D postrouting -o " + networkInterface + " -j masquerade"
}
if ipv6 {
// spacing around ; is important for later parsing of postup/postdown in wireguard/common.go
postUp += "ip6tables -A FORWARD -i " + networkInterface + " -j ACCEPT ; "
postUp += "ip6tables -A FORWARD -o " + networkInterface + " -j ACCEPT ; "
postUp += "ip6tables -t nat -A POSTROUTING -o " + networkInterface + " -j MASQUERADE"
postUp += "ip6tables -t nat -A postrouting -o " + networkInterface + " -j masquerade"
// doesn't remove potentially empty tables or chains
postDown += "ip6tables -D FORWARD -i " + networkInterface + " -j ACCEPT ; "
postDown += "ip6tables -D FORWARD -o " + networkInterface + " -j ACCEPT ; "
postDown += "ip6tables -t nat -D POSTROUTING -o " + networkInterface + " -j MASQUERADE"
postDown += "ip6tables -t nat -D postrouting -o " + networkInterface + " -j masquerade"
}
return postUp, postDown
}
@ -401,8 +402,8 @@ func firewallIPTablesCommandsCreateEgress(networkInterface string, gatewayInterf
postDown += "iptables -D FORWARD -o " + networkInterface + " -j ACCEPT"
if egressNatEnabled == "yes" {
postUp += " ; iptables -t nat -A POSTROUTING -o " + gatewayInterface + " -j MASQUERADE"
postDown += " ; iptables -t nat -D POSTROUTING -o " + gatewayInterface + " -j MASQUERADE"
postUp += " ; iptables -t nat -A postrouting -o " + gatewayInterface + " -j masquerade"
postDown += " ; iptables -t nat -D postrouting -o " + gatewayInterface + " -j masquerade"
}
}
if ipv6 {
@ -412,8 +413,8 @@ func firewallIPTablesCommandsCreateEgress(networkInterface string, gatewayInterf
postDown += "ip6tables -D FORWARD -o " + networkInterface + " -j ACCEPT"
if egressNatEnabled == "yes" {
postUp += " ; ip6tables -t nat -A POSTROUTING -o " + gatewayInterface + " -j MASQUERADE"
postDown += " ; ip6tables -t nat -D POSTROUTING -o " + gatewayInterface + " -j MASQUERADE"
postUp += " ; ip6tables -t nat -A postrouting -o " + gatewayInterface + " -j masquerade"
postDown += " ; ip6tables -t nat -D postrouting -o " + gatewayInterface + " -j masquerade"
}
}
return postUp, postDown

View file

@ -76,7 +76,8 @@ type Node struct {
EgressGatewayNatEnabled string `json:"egressgatewaynatenabled" bson:"egressgatewaynatenabled" yaml:"egressgatewaynatenabled"`
EgressGatewayRequest EgressGatewayRequest `json:"egressgatewayrequest" bson:"egressgatewayrequest" yaml:"egressgatewayrequest"`
RelayAddrs []string `json:"relayaddrs" bson:"relayaddrs" yaml:"relayaddrs"`
IngressGatewayRange []string `json:"ingressgatewayrange" bson:"ingressgatewayrange" yaml:"ingressgatewayrange"`
IngressGatewayRange string `json:"ingressgatewayrange" bson:"ingressgatewayrange" yaml:"ingressgatewayrange"`
IngressGatewayRange6 string `json:"ingressgatewayrange6" bson:"ingressgatewayrange6" yaml:"ingressgatewayrange6"`
// IsStatic - refers to if the Endpoint is set manually or dynamically
IsStatic string `json:"isstatic" bson:"isstatic" yaml:"isstatic" validate:"checkyesorno"`
UDPHolePunch string `json:"udpholepunch" bson:"udpholepunch" yaml:"udpholepunch" validate:"checkyesorno"`
@ -370,6 +371,9 @@ func (newNode *Node) Fill(currentNode *Node) { // TODO add new field for nftable
if newNode.IngressGatewayRange == "" {
newNode.IngressGatewayRange = currentNode.IngressGatewayRange
}
if newNode.IngressGatewayRange6 == "" {
newNode.IngressGatewayRange6 = currentNode.IngressGatewayRange6
}
if newNode.IsStatic == "" {
newNode.IsStatic = currentNode.IsStatic
}