open-nomad/client/allocrunner/networking_cni_test.go
Seth Hoenig a65fbeb3b3
client: manually cleanup leaked iptables rules (#15407)
This PR adds a secondary path for cleaning up iptables created for an allocation
when the normal CNI library fails to do so. This typically happens when the state
of the pause container is unexpected - e.g. deleted out of band from Nomad. Before,
the iptables rules would be leaked which could lead to unexpected nat routing
behavior later on (in addition to leaked resources). With this change, we scan
for the rules created on behalf of the allocation being GC'd and delete them.

Fixes #6385
2022-11-28 11:32:16 -06:00

182 lines
6.3 KiB
Go

//go:build linux
package allocrunner
import (
"errors"
"net"
"testing"
"github.com/containerd/go-cni"
"github.com/hashicorp/nomad/ci"
"github.com/hashicorp/nomad/helper/testlog"
"github.com/shoenig/test/must"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type mockIPTables struct {
listCall [2]string
listRules []string
listErr error
deleteCall [2]string
deleteErr error
clearCall [2]string
clearErr error
}
func (ipt *mockIPTables) List(table, chain string) ([]string, error) {
ipt.listCall[0], ipt.listCall[1] = table, chain
return ipt.listRules, ipt.listErr
}
func (ipt *mockIPTables) Delete(table, chain string, rule ...string) error {
ipt.deleteCall[0], ipt.deleteCall[1] = table, chain
return ipt.deleteErr
}
func (ipt *mockIPTables) ClearAndDeleteChain(table, chain string) error {
ipt.clearCall[0], ipt.clearCall[1] = table, chain
return ipt.clearErr
}
func (ipt *mockIPTables) assert(t *testing.T, jumpChain string) {
// List assertions
must.Eq(t, "nat", ipt.listCall[0])
must.Eq(t, "POSTROUTING", ipt.listCall[1])
// Delete assertions
must.Eq(t, "nat", ipt.deleteCall[0])
must.Eq(t, "POSTROUTING", ipt.deleteCall[1])
// Clear assertions
must.Eq(t, "nat", ipt.clearCall[0])
must.Eq(t, jumpChain, ipt.clearCall[1])
}
func TestCNI_forceCleanup(t *testing.T) {
t.Run("ok", func(t *testing.T) {
c := cniNetworkConfigurator{logger: testlog.HCLogger(t)}
ipt := &mockIPTables{
listRules: []string{
`-A POSTROUTING -m comment --comment "CNI portfwd requiring masquerade" -j CNI-HOSTPORT-MASQ`,
`-A POSTROUTING -s 172.17.0.0/16 ! -o docker0 -j MASQUERADE`,
`-A POSTROUTING -s 172.26.64.216/32 -m comment --comment "name: \"nomad\" id: \"79e8bf2e-a9c8-70ac-8d4e-fa5c4da99fbf\"" -j CNI-f2338c31d4de44472fe99c43`,
`-A POSTROUTING -s 172.26.64.217/32 -m comment --comment "name: \"nomad\" id: \"2dd71cac-2b1e-ff08-167c-735f7f9f4964\"" -j CNI-5d36f286cfbb35c5776509ec`,
`-A POSTROUTING -s 172.26.64.218/32 -m comment --comment "name: \"nomad\" id: \"5ff6deb7-9bc1-1491-f20c-e87b15de501d\"" -j CNI-2fe7686eac2fe43714a7b850`,
`-A POSTROUTING -m mark --mark 0x2000/0x2000 -j MASQUERADE`,
`-A POSTROUTING -m comment --comment "CNI portfwd masquerade mark" -j MARK --set-xmark 0x2000/0x2000`,
},
}
err := c.forceCleanup(ipt, "2dd71cac-2b1e-ff08-167c-735f7f9f4964")
must.NoError(t, err)
ipt.assert(t, "CNI-5d36f286cfbb35c5776509ec")
})
t.Run("missing allocation", func(t *testing.T) {
c := cniNetworkConfigurator{logger: testlog.HCLogger(t)}
ipt := &mockIPTables{
listRules: []string{
`-A POSTROUTING -m comment --comment "CNI portfwd requiring masquerade" -j CNI-HOSTPORT-MASQ`,
`-A POSTROUTING -s 172.17.0.0/16 ! -o docker0 -j MASQUERADE`,
`-A POSTROUTING -s 172.26.64.216/32 -m comment --comment "name: \"nomad\" id: \"79e8bf2e-a9c8-70ac-8d4e-fa5c4da99fbf\"" -j CNI-f2338c31d4de44472fe99c43`,
`-A POSTROUTING -s 172.26.64.217/32 -m comment --comment "name: \"nomad\" id: \"262d57a7-8f85-f3a4-9c3b-120c00ccbff1\"" -j CNI-5d36f286cfbb35c5776509ec`,
`-A POSTROUTING -s 172.26.64.218/32 -m comment --comment "name: \"nomad\" id: \"5ff6deb7-9bc1-1491-f20c-e87b15de501d\"" -j CNI-2fe7686eac2fe43714a7b850`,
`-A POSTROUTING -m mark --mark 0x2000/0x2000 -j MASQUERADE`,
`-A POSTROUTING -m comment --comment "CNI portfwd masquerade mark" -j MARK --set-xmark 0x2000/0x2000`,
},
}
err := c.forceCleanup(ipt, "2dd71cac-2b1e-ff08-167c-735f7f9f4964")
must.EqError(t, err, "failed to find postrouting rule for alloc 2dd71cac-2b1e-ff08-167c-735f7f9f4964")
})
t.Run("list error", func(t *testing.T) {
c := cniNetworkConfigurator{logger: testlog.HCLogger(t)}
ipt := &mockIPTables{listErr: errors.New("list error")}
err := c.forceCleanup(ipt, "2dd71cac-2b1e-ff08-167c-735f7f9f4964")
must.EqError(t, err, "failed to list iptables rules: list error")
})
t.Run("delete error", func(t *testing.T) {
c := cniNetworkConfigurator{logger: testlog.HCLogger(t)}
ipt := &mockIPTables{
deleteErr: errors.New("delete error"),
listRules: []string{
`-A POSTROUTING -s 172.26.64.217/32 -m comment --comment "name: \"nomad\" id: \"2dd71cac-2b1e-ff08-167c-735f7f9f4964\"" -j CNI-5d36f286cfbb35c5776509ec`,
},
}
err := c.forceCleanup(ipt, "2dd71cac-2b1e-ff08-167c-735f7f9f4964")
must.EqError(t, err, "failed to cleanup iptables rules for alloc 2dd71cac-2b1e-ff08-167c-735f7f9f4964")
})
t.Run("clear error", func(t *testing.T) {
c := cniNetworkConfigurator{logger: testlog.HCLogger(t)}
ipt := &mockIPTables{
clearErr: errors.New("clear error"),
listRules: []string{
`-A POSTROUTING -s 172.26.64.217/32 -m comment --comment "name: \"nomad\" id: \"2dd71cac-2b1e-ff08-167c-735f7f9f4964\"" -j CNI-5d36f286cfbb35c5776509ec`,
},
}
err := c.forceCleanup(ipt, "2dd71cac-2b1e-ff08-167c-735f7f9f4964")
must.EqError(t, err, "failed to cleanup iptables rules for alloc 2dd71cac-2b1e-ff08-167c-735f7f9f4964")
})
}
// TestCNI_cniToAllocNet_Fallback asserts if a CNI plugin result lacks an IP on
// its sandbox interface, the first IP found is used.
func TestCNI_cniToAllocNet_Fallback(t *testing.T) {
ci.Parallel(t)
// Calico's CNI plugin v3.12.3 has been observed to return the
// following:
cniResult := &cni.CNIResult{
Interfaces: map[string]*cni.Config{
"cali39179aa3-74": {},
"eth0": {
IPConfigs: []*cni.IPConfig{
{
IP: net.IPv4(192, 168, 135, 232),
},
},
},
},
}
// Only need a logger
c := &cniNetworkConfigurator{
logger: testlog.HCLogger(t),
}
allocNet, err := c.cniToAllocNet(cniResult)
require.NoError(t, err)
require.NotNil(t, allocNet)
assert.Equal(t, "192.168.135.232", allocNet.Address)
assert.Equal(t, "eth0", allocNet.InterfaceName)
assert.Nil(t, allocNet.DNS)
}
// TestCNI_cniToAllocNet_Invalid asserts an error is returned if a CNI plugin
// result lacks any IP addresses. This has not been observed, but Nomad still
// must guard against invalid results from external plugins.
func TestCNI_cniToAllocNet_Invalid(t *testing.T) {
ci.Parallel(t)
cniResult := &cni.CNIResult{
Interfaces: map[string]*cni.Config{
"eth0": {},
"veth1": {
IPConfigs: []*cni.IPConfig{},
},
},
}
// Only need a logger
c := &cniNetworkConfigurator{
logger: testlog.HCLogger(t),
}
allocNet, err := c.cniToAllocNet(cniResult)
require.Error(t, err)
require.Nil(t, allocNet)
}