open-nomad/client/allocrunner/networking_cni_test.go
Yorick Gersie 3e66291b0e
cni: ensure to setup CNI addresses in deterministic order (#17766)
* cni: ensure to setup CNI addresses in deterministic order

  Currently as commented in the code the go-cni library returns an unordered map
  of interfaces. In cases where there are multiple CNI interfaces being created this
  creates a problem with service registration and healthchecking because the first
  address in the map is being used.

  The use case we have where this is an issue is that we run CNI with the macvlan
  plugin to isolate workloads, but they still need to be able to access the host on
  a static address to be able to perform local resolving and hit host services like
  the Consul agent API. To make this work there are 2 options, you either add a
  macvlan interface on the host with an assigned address for each VLAN you have or
  you create an additional veth bridged interface in the container namespace.
  We chose the latter option through a custom CNI plugin but the ordering issue
  leaves us with incorrect service registration.

* Updates after feedback

 * First check for the CNIResult interfaces length, if it's zero we don't need to proceed
   at all.
 * Use sorted interfaces list for the address fallback scenario as well.
 * Remove "found" log message logic, when an address isn't found an error is returned stating
   the allocation could not be configured as an address was missing from the CNIResult. If we
   still need a Warn message then we can add it to the condition that returns the error if no
   address could be found instead of using the "found" bool logic.
2023-07-06 13:25:29 -07:00

201 lines
6.7 KiB
Go

// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0
//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_NoInterfaces asserts an error is returned if CNIResult
// contains no interfaces.
func TestCNI_cniToAllocNet_NoInterfaces(t *testing.T) {
ci.Parallel(t)
cniResult := &cni.CNIResult{}
// Only need a logger
c := &cniNetworkConfigurator{
logger: testlog.HCLogger(t),
}
allocNet, err := c.cniToAllocNet(cniResult)
require.Error(t, err)
require.Nil(t, allocNet)
}
// 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)
}