Files
podman/pkg/specgen/generate/pod_create.go
Stefano Brivio aa47e05ae4 libpod: Add pasta networking mode
Conceptually equivalent to networking by means of slirp4netns(1),
with a few practical differences:

- pasta(1) forks to background once networking is configured in the
  namespace and quits on its own once the namespace is deleted:
  file descriptor synchronisation and PID tracking are not needed

- port forwarding is configured via command line options at start-up,
  instead of an API socket: this is taken care of right away as we're
  about to start pasta

- there's no need for further selection of port forwarding modes:
  pasta behaves similarly to containers-rootlessport for local binds
  (splice() instead of read()/write() pairs, without L2-L4
  translation), and keeps the original source address for non-local
  connections like slirp4netns does

- IPv6 is not an experimental feature, and enabled by default. IPv6
  port forwarding is supported

- by default, addresses and routes are copied from the host, that is,
  container users will see the same IP address and routes as if they
  were in the init namespace context. The interface name is also
  sourced from the host upstream interface with the first default
  route in the routing table. This is also configurable as documented

- sandboxing and seccomp(2) policies cannot be disabled

- only rootless mode is supported.

See https://passt.top for more details about pasta.

Also add a link to the maintained build of pasta(1) manual as valid
in the man page cross-reference checks: that's where the man page
for the latest build actually is -- it's not on Github and it doesn't
match any existing pattern, so add it explicitly.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-11-08 00:16:35 +01:00

358 lines
10 KiB
Go

package generate
import (
"context"
"encoding/json"
"fmt"
"net"
"os"
"strconv"
"strings"
"github.com/containers/podman/v4/libpod"
"github.com/containers/podman/v4/libpod/define"
"github.com/containers/podman/v4/pkg/domain/entities"
"github.com/containers/podman/v4/pkg/specgen"
"github.com/containers/podman/v4/pkg/specgenutil"
"github.com/opencontainers/runtime-spec/specs-go"
"github.com/sirupsen/logrus"
)
func MakePod(p *entities.PodSpec, rt *libpod.Runtime) (*libpod.Pod, error) {
if err := p.PodSpecGen.Validate(); err != nil {
return nil, err
}
if p.PodSpecGen.ResourceLimits == nil {
p.PodSpecGen.ResourceLimits = &specs.LinuxResources{}
}
if !p.PodSpecGen.NoInfra {
imageName, err := PullOrBuildInfraImage(rt, p.PodSpecGen.InfraImage)
if err != nil {
return nil, err
}
p.PodSpecGen.InfraImage = imageName
p.PodSpecGen.InfraContainerSpec.RawImageName = imageName
}
if !p.PodSpecGen.NoInfra && p.PodSpecGen.InfraContainerSpec != nil {
var err error
p.PodSpecGen.InfraContainerSpec, err = MapSpec(&p.PodSpecGen)
if err != nil {
return nil, err
}
}
if !p.PodSpecGen.NoInfra {
err := specgen.FinishThrottleDevices(p.PodSpecGen.InfraContainerSpec)
if err != nil {
return nil, err
}
if p.PodSpecGen.InfraContainerSpec.ResourceLimits != nil &&
p.PodSpecGen.InfraContainerSpec.ResourceLimits.BlockIO != nil {
p.PodSpecGen.ResourceLimits.BlockIO = p.PodSpecGen.InfraContainerSpec.ResourceLimits.BlockIO
}
err = specgen.WeightDevices(p.PodSpecGen.InfraContainerSpec)
if err != nil {
return nil, err
}
p.PodSpecGen.ResourceLimits = p.PodSpecGen.InfraContainerSpec.ResourceLimits
}
options, err := createPodOptions(&p.PodSpecGen)
if err != nil {
return nil, err
}
pod, err := rt.NewPod(context.Background(), p.PodSpecGen, options...)
if err != nil {
return nil, err
}
if !p.PodSpecGen.NoInfra && p.PodSpecGen.InfraContainerSpec != nil {
if p.PodSpecGen.InfraContainerSpec.Name == "" {
p.PodSpecGen.InfraContainerSpec.Name = pod.ID()[:12] + "-infra"
}
_, err = CompleteSpec(context.Background(), rt, p.PodSpecGen.InfraContainerSpec)
if err != nil {
return nil, err
}
p.PodSpecGen.InfraContainerSpec.User = "" // infraSpec user will get incorrectly assigned via the container creation process, overwrite here
// infra's resource limits are used as a parsing tool,
// we do not want infra to get these resources in its cgroup
// make sure of that here.
p.PodSpecGen.InfraContainerSpec.ResourceLimits = nil
p.PodSpecGen.InfraContainerSpec.WeightDevice = nil
rtSpec, spec, opts, err := MakeContainer(context.Background(), rt, p.PodSpecGen.InfraContainerSpec, false, nil)
if err != nil {
return nil, err
}
spec.Pod = pod.ID()
opts = append(opts, rt.WithPod(pod))
spec.CgroupParent = pod.CgroupParent()
infraCtr, err := ExecuteCreate(context.Background(), rt, rtSpec, spec, true, opts...)
if err != nil {
return nil, err
}
pod, err = rt.AddInfra(context.Background(), pod, infraCtr)
if err != nil {
return nil, err
}
} else {
// SavePod is used to save the pod state and trigger a create event even if infra is not created
err := rt.SavePod(pod)
if err != nil {
return nil, err
}
}
return pod, nil
}
func createPodOptions(p *specgen.PodSpecGenerator) ([]libpod.PodCreateOption, error) {
var (
options []libpod.PodCreateOption
)
if !p.NoInfra {
options = append(options, libpod.WithInfraContainer())
if p.ShareParent == nil || (p.ShareParent != nil && *p.ShareParent) {
options = append(options, libpod.WithPodParent())
}
nsOptions, err := GetNamespaceOptions(p.SharedNamespaces, p.InfraContainerSpec.NetNS.IsHost())
if err != nil {
return nil, err
}
options = append(options, nsOptions...)
// Use pod user and infra userns only when --userns is not set to host
if !p.InfraContainerSpec.UserNS.IsHost() && !p.InfraContainerSpec.UserNS.IsDefault() {
options = append(options, libpod.WithPodUser())
}
}
if len(p.ServiceContainerID) > 0 {
options = append(options, libpod.WithServiceContainer(p.ServiceContainerID))
}
if len(p.CgroupParent) > 0 {
options = append(options, libpod.WithPodCgroupParent(p.CgroupParent))
}
if len(p.Labels) > 0 {
options = append(options, libpod.WithPodLabels(p.Labels))
}
if len(p.Name) > 0 {
options = append(options, libpod.WithPodName(p.Name))
}
if p.PodCreateCommand != nil {
options = append(options, libpod.WithPodCreateCommand(p.PodCreateCommand))
}
if len(p.Hostname) > 0 {
options = append(options, libpod.WithPodHostname(p.Hostname))
}
if p.ResourceLimits != nil {
options = append(options, libpod.WithPodResources(*p.ResourceLimits))
}
options = append(options, libpod.WithPodExitPolicy(p.ExitPolicy))
return options, nil
}
// MapSpec modifies the already filled Infra specgenerator,
// replacing necessary values with those specified in pod creation
func MapSpec(p *specgen.PodSpecGenerator) (*specgen.SpecGenerator, error) {
if len(p.PortMappings) > 0 {
ports, err := ParsePortMapping(p.PortMappings, nil)
if err != nil {
return nil, err
}
p.InfraContainerSpec.PortMappings = ports
}
switch p.NetNS.NSMode {
case specgen.Default, "":
if p.NoInfra {
logrus.Debugf("No networking because the infra container is missing")
break
}
case specgen.Bridge:
p.InfraContainerSpec.NetNS.NSMode = specgen.Bridge
logrus.Debugf("Pod using bridge network mode")
case specgen.Private:
p.InfraContainerSpec.NetNS.NSMode = specgen.Private
logrus.Debugf("Pod will use default network mode")
case specgen.Host:
logrus.Debugf("Pod will use host networking")
if len(p.InfraContainerSpec.PortMappings) > 0 ||
len(p.InfraContainerSpec.Networks) > 0 ||
p.InfraContainerSpec.NetNS.NSMode == specgen.NoNetwork {
return nil, fmt.Errorf("cannot set host network if network-related configuration is specified: %w", define.ErrInvalidArg)
}
p.InfraContainerSpec.NetNS.NSMode = specgen.Host
case specgen.Slirp:
logrus.Debugf("Pod will use slirp4netns")
if p.InfraContainerSpec.NetNS.NSMode != specgen.Host {
p.InfraContainerSpec.NetworkOptions = p.NetworkOptions
p.InfraContainerSpec.NetNS.NSMode = specgen.Slirp
}
case specgen.Pasta:
logrus.Debugf("Pod will use pasta")
if p.InfraContainerSpec.NetNS.NSMode != specgen.Host {
p.InfraContainerSpec.NetworkOptions = p.NetworkOptions
p.InfraContainerSpec.NetNS.NSMode = specgen.Pasta
}
case specgen.Path:
logrus.Debugf("Pod will use namespace path networking")
p.InfraContainerSpec.NetNS.NSMode = specgen.Path
p.InfraContainerSpec.NetNS.Value = p.PodNetworkConfig.NetNS.Value
case specgen.NoNetwork:
logrus.Debugf("Pod will not use networking")
if len(p.InfraContainerSpec.PortMappings) > 0 ||
len(p.InfraContainerSpec.Networks) > 0 ||
p.InfraContainerSpec.NetNS.NSMode == specgen.Host {
return nil, fmt.Errorf("cannot disable pod network if network-related configuration is specified: %w", define.ErrInvalidArg)
}
p.InfraContainerSpec.NetNS.NSMode = specgen.NoNetwork
default:
return nil, fmt.Errorf("pods presently do not support network mode %s", p.NetNS.NSMode)
}
if len(p.InfraCommand) > 0 {
p.InfraContainerSpec.Entrypoint = p.InfraCommand
}
if len(p.HostAdd) > 0 {
p.InfraContainerSpec.HostAdd = p.HostAdd
}
if len(p.DNSServer) > 0 {
var dnsServers []net.IP
dnsServers = append(dnsServers, p.DNSServer...)
p.InfraContainerSpec.DNSServers = dnsServers
}
if len(p.DNSOption) > 0 {
p.InfraContainerSpec.DNSOptions = p.DNSOption
}
if len(p.DNSSearch) > 0 {
p.InfraContainerSpec.DNSSearch = p.DNSSearch
}
if p.NoManageResolvConf {
p.InfraContainerSpec.UseImageResolvConf = true
}
if len(p.Networks) > 0 {
p.InfraContainerSpec.Networks = p.Networks
}
// deprecated cni networks for api users
if len(p.CNINetworks) > 0 {
p.InfraContainerSpec.CNINetworks = p.CNINetworks
}
if p.NoManageHosts {
p.InfraContainerSpec.UseImageHosts = p.NoManageHosts
}
if len(p.InfraConmonPidFile) > 0 {
p.InfraContainerSpec.ConmonPidFile = p.InfraConmonPidFile
}
p.InfraContainerSpec.Image = p.InfraImage
return p.InfraContainerSpec, nil
}
func PodConfigToSpec(rt *libpod.Runtime, spec *specgen.PodSpecGenerator, infraOptions *entities.ContainerCreateOptions, id string) (p *libpod.Pod, err error) {
pod, err := rt.LookupPod(id)
if err != nil {
return nil, err
}
infraSpec := &specgen.SpecGenerator{}
if pod.HasInfraContainer() {
infraID, err := pod.InfraContainerID()
if err != nil {
return nil, err
}
_, _, err = ConfigToSpec(rt, infraSpec, infraID)
if err != nil {
return nil, err
}
infraSpec.Hostname = ""
infraSpec.CgroupParent = ""
infraSpec.Pod = "" // remove old pod...
infraOptions.IsClone = true
infraOptions.IsInfra = true
n := infraSpec.Name
_, err = rt.LookupContainer(n + "-clone")
if err == nil { // if we found a ctr with this name, set it so the below switch can tell
n += "-clone"
}
switch {
case strings.Contains(n, "-clone"):
ind := strings.Index(n, "-clone") + 6
num, err := strconv.Atoi(n[ind:])
if num == 0 && err != nil { // clone1 is hard to get with this logic, just check for it here.
_, err = rt.LookupContainer(n + "1")
if err != nil {
infraSpec.Name = n + "1"
break
}
} else {
n = n[0:ind]
}
err = nil
count := num
for err == nil {
count++
tempN := n + strconv.Itoa(count)
_, err = rt.LookupContainer(tempN)
}
n += strconv.Itoa(count)
infraSpec.Name = n
default:
infraSpec.Name = n + "-clone"
}
err = specgenutil.FillOutSpecGen(infraSpec, infraOptions, []string{})
if err != nil {
return nil, err
}
out, err := CompleteSpec(context.Background(), rt, infraSpec)
if err != nil {
return nil, err
}
// Print warnings
if len(out) > 0 {
for _, w := range out {
fmt.Println("Could not properly complete the spec as expected:")
fmt.Fprintf(os.Stderr, "%s\n", w)
}
}
spec.InfraContainerSpec = infraSpec
matching, err := json.Marshal(infraSpec)
if err != nil {
return nil, err
}
// track name before unmarshal so we do not overwrite w/ infra
name := spec.Name
err = json.Unmarshal(matching, spec)
if err != nil {
return nil, err
}
spec.Name = name
}
// need to reset hostname, name etc of both pod and infra
spec.Hostname = ""
if len(spec.InfraContainerSpec.Image) > 0 {
spec.InfraImage = spec.InfraContainerSpec.Image
}
return pod, nil
}