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Diffstat (limited to 'libpod/container_internal_linux.go')
-rw-r--r--libpod/container_internal_linux.go228
1 files changed, 71 insertions, 157 deletions
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index f8d0a124c..d409f7a04 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -28,6 +28,7 @@ import (
"github.com/containers/buildah/pkg/chrootuser"
"github.com/containers/buildah/pkg/overlay"
butil "github.com/containers/buildah/util"
+ "github.com/containers/common/libnetwork/etchosts"
"github.com/containers/common/libnetwork/types"
"github.com/containers/common/pkg/apparmor"
"github.com/containers/common/pkg/cgroups"
@@ -49,6 +50,7 @@ import (
"github.com/containers/podman/v4/version"
"github.com/containers/storage/pkg/archive"
"github.com/containers/storage/pkg/idtools"
+ "github.com/containers/storage/pkg/lockfile"
securejoin "github.com/cyphar/filepath-securejoin"
runcuser "github.com/opencontainers/runc/libcontainer/user"
spec "github.com/opencontainers/runtime-spec/specs-go"
@@ -2072,23 +2074,25 @@ func (c *Container) makeBindMounts() error {
// check if dependency container has an /etc/hosts file.
// It may not have one, so only use it if it does.
- hostsPath, exists := bindMounts["/etc/hosts"]
+ hostsPath, exists := bindMounts[config.DefaultHostsFile]
if !c.config.UseImageHosts && exists {
- depCtr.lock.Lock()
- // generate a hosts file for the dependency container,
- // based on either its old hosts file, or the default,
- // and add the relevant information from the new container (hosts and IP)
- hostsPath, err = depCtr.appendHosts(hostsPath, c)
+ // we cannot use the dependency container lock due ABBA deadlocks in cleanup()
+ lock, err := lockfile.GetLockfile(hostsPath)
+ if err != nil {
+ return fmt.Errorf("failed to lock hosts file: %w", err)
+ }
+ lock.Lock()
+ // add the newly added container to the hosts file
+ // we always use 127.0.0.1 as ip since they have the same netns
+ err = etchosts.Add(hostsPath, getLocalhostHostEntry(c))
+ lock.Unlock()
if err != nil {
- depCtr.lock.Unlock()
return errors.Wrapf(err, "error creating hosts file for container %s which depends on container %s", c.ID(), depCtr.ID())
}
- depCtr.lock.Unlock()
// finally, save it in the new container
- err := c.mountIntoRootDirs("/etc/hosts", hostsPath)
-
+ err = c.mountIntoRootDirs(config.DefaultHostsFile, hostsPath)
if err != nil {
return errors.Wrapf(err, "error assigning mounts to container %s", c.ID())
}
@@ -2116,7 +2120,7 @@ func (c *Container) makeBindMounts() error {
}
if !c.config.UseImageHosts {
- if err := c.updateHosts("/etc/hosts"); err != nil {
+ if err := c.createHosts(); err != nil {
return errors.Wrapf(err, "error creating hosts file for container %s", c.ID())
}
}
@@ -2135,7 +2139,7 @@ func (c *Container) makeBindMounts() error {
}
} else {
if !c.config.UseImageHosts && c.state.BindMounts["/etc/hosts"] == "" {
- if err := c.updateHosts("/etc/hosts"); err != nil {
+ if err := c.createHosts(); err != nil {
return errors.Wrapf(err, "error creating hosts file for container %s", c.ID())
}
}
@@ -2521,169 +2525,79 @@ func (c *Container) removeNameserver(ips []string) error {
return nil
}
-// updateHosts updates the container's hosts file
-func (c *Container) updateHosts(path string) error {
- var hosts string
-
- orig, err := ioutil.ReadFile(path)
- if err != nil {
- // Ignore if the path does not exist
- if !os.IsNotExist(err) {
- return err
- }
- } else {
- hosts = string(orig)
- }
-
- hosts += c.getHosts()
- hosts = c.appendLocalhost(hosts)
-
- newHosts, err := c.writeStringToRundir("hosts", hosts)
- if err != nil {
- return err
- }
-
- if err = c.mountIntoRootDirs("/etc/hosts", newHosts); err != nil {
- return err
- }
-
- return nil
+func getLocalhostHostEntry(c *Container) etchosts.HostEntries {
+ return etchosts.HostEntries{{IP: "127.0.0.1", Names: []string{c.Hostname(), c.config.Name}}}
}
-// based on networking mode we may want to append the localhost
-// if there isn't any record for it and also this should happen
-// in slirp4netns and similar network modes.
-func (c *Container) appendLocalhost(hosts string) string {
- if !strings.Contains(hosts, "localhost") &&
- !c.config.NetMode.IsHost() {
- hosts += "127.0.0.1\tlocalhost\n::1\tlocalhost\n"
- }
-
- return hosts
-}
-
-// appendHosts appends a container's config and state pertaining to hosts to a container's
-// local hosts file. netCtr is the container from which the netNS information is
-// taken.
-// path is the basis of the hosts file, into which netCtr's netNS information will be appended.
-// FIXME. Path should be used by this function,but I am not sure what is correct; remove //lint
-// once this is fixed
-func (c *Container) appendHosts(path string, netCtr *Container) (string, error) { //nolint
- return c.appendStringToRunDir("hosts", netCtr.getHosts())
-}
-
-// getHosts finds the pertinent information for a container's host file in its config and state
-// and returns a string in a format that can be written to the host file
-func (c *Container) getHosts() string {
- var hosts string
-
- if len(c.config.HostAdd) > 0 {
- for _, host := range c.config.HostAdd {
- // the host format has already been verified at this point
- fields := strings.SplitN(host, ":", 2)
- hosts += fmt.Sprintf("%s %s\n", fields[1], fields[0])
- }
- }
-
- hosts += c.cniHosts()
-
- // Add hostname for slirp4netns
- if c.Hostname() != "" {
- if c.config.NetMode.IsSlirp4netns() {
- // When using slirp4netns, the interface gets a static IP
- slirp4netnsIP, err := GetSlirp4netnsIP(c.slirp4netnsSubnet)
- if err != nil {
- logrus.Warnf("Failed to determine slirp4netnsIP: %v", err.Error())
- } else {
- hosts += fmt.Sprintf("# used by slirp4netns\n%s\t%s %s\n", slirp4netnsIP.String(), c.Hostname(), c.config.Name)
- }
+// getHostsEntries returns the container ip host entries for the correct netmode
+func (c *Container) getHostsEntries() (etchosts.HostEntries, error) {
+ var entries etchosts.HostEntries
+ names := []string{c.Hostname(), c.config.Name}
+ switch {
+ case c.config.NetMode.IsBridge():
+ entries = etchosts.GetNetworkHostEntries(c.state.NetworkStatus, names...)
+ case c.config.NetMode.IsSlirp4netns():
+ ip, err := GetSlirp4netnsIP(c.slirp4netnsSubnet)
+ if err != nil {
+ return nil, err
}
-
- // Do we have a network namespace?
- netNone := false
- if c.config.NetNsCtr == "" && !c.config.CreateNetNS {
+ entries = etchosts.HostEntries{{IP: ip.String(), Names: names}}
+ default:
+ // check for net=none
+ if !c.config.CreateNetNS {
for _, ns := range c.config.Spec.Linux.Namespaces {
if ns.Type == spec.NetworkNamespace {
if ns.Path == "" {
- netNone = true
+ entries = etchosts.HostEntries{{IP: "127.0.0.1", Names: names}}
}
break
}
}
}
- // If we are net=none (have a network namespace, but not connected to
- // anything) add the container's name and hostname to localhost.
- if netNone {
- hosts += fmt.Sprintf("127.0.0.1 %s %s\n", c.Hostname(), c.config.Name)
- }
}
+ return entries, nil
+}
- // Add gateway entry if we are not in a machine. If we use podman machine
- // the gvproxy dns server will take care of host.containers.internal.
- // https://github.com/containers/gvisor-tap-vsock/commit/1108ea45162281046d239047a6db9bc187e64b08
- if !c.runtime.config.Engine.MachineEnabled {
- var depCtr *Container
- netStatus := c.getNetworkStatus()
- if c.config.NetNsCtr != "" {
- // ignoring the error because there isn't anything to do
- depCtr, _ = c.getRootNetNsDepCtr()
- } else if len(netStatus) != 0 {
- depCtr = c
+func (c *Container) createHosts() error {
+ var containerIPsEntries etchosts.HostEntries
+ var err error
+ // if we configure the netns after the container create we should not add
+ // the hosts here since we have no information about the actual ips
+ // instead we will add them in c.completeNetworkSetup()
+ if !c.config.PostConfigureNetNS {
+ containerIPsEntries, err = c.getHostsEntries()
+ if err != nil {
+ return fmt.Errorf("failed to get container ip host entries: %w", err)
}
+ }
+ baseHostFile, err := etchosts.GetBaseHostFile(c.runtime.config.Containers.BaseHostsFile, c.state.Mountpoint)
+ if err != nil {
+ return err
+ }
- // getLocalIP returns the non loopback local IP of the host
- getLocalIP := func() string {
- addrs, err := net.InterfaceAddrs()
- if err != nil {
- return ""
- }
- for _, address := range addrs {
- // check the address type and if it is not a loopback the display it
- if ipnet, ok := address.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
- if ipnet.IP.To4() != nil {
- return ipnet.IP.String()
- }
- }
- }
- return ""
- }
+ targetFile := filepath.Join(c.state.RunDir, "hosts")
+ err = etchosts.New(&etchosts.Params{
+ BaseFile: baseHostFile,
+ ExtraHosts: c.config.HostAdd,
+ ContainerIPs: containerIPsEntries,
+ HostContainersInternalIP: etchosts.GetHostContainersInternalIP(c.runtime.config, c.state.NetworkStatus, c.runtime.network),
+ TargetFile: targetFile,
+ })
+ if err != nil {
+ return err
+ }
- if depCtr != nil {
- host := ""
- outer:
- for net, status := range depCtr.getNetworkStatus() {
- network, err := c.runtime.network.NetworkInspect(net)
- // only add the host entry for bridge networks
- // ip/macvlan gateway is normally not on the host
- if err != nil || network.Driver != types.BridgeNetworkDriver {
- continue
- }
- for _, netInt := range status.Interfaces {
- for _, netAddress := range netInt.Subnets {
- if netAddress.Gateway != nil {
- host = fmt.Sprintf("%s host.containers.internal\n", netAddress.Gateway.String())
- break outer
- }
- }
- }
- }
- // if no bridge gw was found try to use a local ip
- if host == "" {
- if ip := getLocalIP(); ip != "" {
- host = fmt.Sprintf("%s\t%s\n", ip, "host.containers.internal")
- }
- }
- hosts += host
- } else if c.config.NetMode.IsSlirp4netns() {
- if ip := getLocalIP(); ip != "" {
- hosts += fmt.Sprintf("%s\t%s\n", ip, "host.containers.internal")
- }
- } else {
- logrus.Debug("Network configuration does not support host.containers.internal address")
- }
+ if err := os.Chown(targetFile, c.RootUID(), c.RootGID()); err != nil {
+ return err
+ }
+ if err := label.Relabel(targetFile, c.MountLabel(), false); err != nil {
+ return err
}
- return hosts
+ if err = c.mountIntoRootDirs(config.DefaultHostsFile, targetFile); err != nil {
+ return err
+ }
+ return nil
}
// generateGroupEntry generates an entry or entries into /etc/group as
generated by cgit v1.2.3-54-g00ecf (git 2.39.0) at 2024-11-16 17:40:13 +0000