diff options
Diffstat (limited to 'libpod/container_internal_linux.go')
| -rw-r--r-- | libpod/container_internal_linux.go | 163 |
1 files changed, 32 insertions, 131 deletions
diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go index b298014df..41c0ac595 100644 --- a/libpod/container_internal_linux.go +++ b/libpod/container_internal_linux.go @@ -9,7 +9,6 @@ import ( "io" "io/ioutil" "math" - "net" "os" "os/user" "path" @@ -29,6 +28,7 @@ import ( "github.com/containers/buildah/pkg/overlay" butil "github.com/containers/buildah/util" "github.com/containers/common/libnetwork/etchosts" + "github.com/containers/common/libnetwork/resolvconf" "github.com/containers/common/libnetwork/types" "github.com/containers/common/pkg/apparmor" "github.com/containers/common/pkg/cgroups" @@ -44,7 +44,6 @@ import ( "github.com/containers/podman/v4/pkg/checkpoint/crutils" "github.com/containers/podman/v4/pkg/criu" "github.com/containers/podman/v4/pkg/lookup" - "github.com/containers/podman/v4/pkg/resolvconf" "github.com/containers/podman/v4/pkg/rootless" "github.com/containers/podman/v4/pkg/util" "github.com/containers/podman/v4/utils" @@ -2316,49 +2315,10 @@ rootless=%d // generateResolvConf generates a containers resolv.conf func (c *Container) generateResolvConf() error { var ( - nameservers []string networkNameServers []string networkSearchDomains []string ) - hostns := true - resolvConf := "/etc/resolv.conf" - for _, namespace := range c.config.Spec.Linux.Namespaces { - if namespace.Type == spec.NetworkNamespace { - hostns = false - if namespace.Path != "" && !strings.HasPrefix(namespace.Path, "/proc/") { - definedPath := filepath.Join("/etc/netns", filepath.Base(namespace.Path), "resolv.conf") - _, err := os.Stat(definedPath) - if err == nil { - resolvConf = definedPath - } else if !os.IsNotExist(err) { - return err - } - } - break - } - } - - contents, err := ioutil.ReadFile(resolvConf) - // resolv.conf doesn't have to exists - if err != nil && !os.IsNotExist(err) { - return err - } - - ns := resolvconf.GetNameservers(contents) - // check if systemd-resolved is used, assume it is used when 127.0.0.53 is the only nameserver - if !hostns && len(ns) == 1 && ns[0] == "127.0.0.53" { - // read the actual resolv.conf file for systemd-resolved - resolvedContents, err := ioutil.ReadFile("/run/systemd/resolve/resolv.conf") - if err != nil { - if !os.IsNotExist(err) { - return errors.Wrapf(err, "detected that systemd-resolved is in use, but could not locate real resolv.conf") - } - } else { - contents = resolvedContents - } - } - netStatus := c.getNetworkStatus() for _, status := range netStatus { if status.DNSServerIPs != nil { @@ -2378,34 +2338,18 @@ func (c *Container) generateResolvConf() error { return err } - // Ensure that the container's /etc/resolv.conf is compatible with its - // network configuration. - resolv, err := resolvconf.FilterResolvDNS(contents, ipv6, !hostns) - if err != nil { - return errors.Wrapf(err, "error parsing host resolv.conf") + nameservers := make([]string, 0, len(c.runtime.config.Containers.DNSServers)+len(c.config.DNSServer)) + nameservers = append(nameservers, c.runtime.config.Containers.DNSServers...) + for _, ip := range c.config.DNSServer { + nameservers = append(nameservers, ip.String()) } - - dns := make([]net.IP, 0, len(c.runtime.config.Containers.DNSServers)+len(c.config.DNSServer)) - for _, i := range c.runtime.config.Containers.DNSServers { - result := net.ParseIP(i) - if result == nil { - return errors.Wrapf(define.ErrInvalidArg, "invalid IP address %s", i) - } - dns = append(dns, result) - } - dns = append(dns, c.config.DNSServer...) // If the user provided dns, it trumps all; then dns masq; then resolv.conf var search []string - switch { - case len(dns) > 0: - // We store DNS servers as net.IP, so need to convert to string - for _, server := range dns { - nameservers = append(nameservers, server.String()) - } - default: - // Make a new resolv.conf + keepHostServers := false + if len(nameservers) == 0 { + keepHostServers = true // first add the nameservers from the networks status - nameservers = append(nameservers, networkNameServers...) + nameservers = networkNameServers // when we add network dns server we also have to add the search domains search = networkSearchDomains // slirp4netns has a built in DNS forwarder. @@ -2417,38 +2361,34 @@ func (c *Container) generateResolvConf() error { nameservers = append(nameservers, slirp4netnsDNS.String()) } } - nameservers = append(nameservers, resolvconf.GetNameservers(resolv.Content)...) } if len(c.config.DNSSearch) > 0 || len(c.runtime.config.Containers.DNSSearches) > 0 { - if !cutil.StringInSlice(".", c.config.DNSSearch) { - search = append(search, c.runtime.config.Containers.DNSSearches...) - search = append(search, c.config.DNSSearch...) - } - } else { - search = append(search, resolvconf.GetSearchDomains(resolv.Content)...) + customSearch := make([]string, 0, len(c.config.DNSSearch)+len(c.runtime.config.Containers.DNSSearches)) + customSearch = append(customSearch, c.runtime.config.Containers.DNSSearches...) + customSearch = append(customSearch, c.config.DNSSearch...) + search = customSearch } - var options []string - if len(c.config.DNSOption) > 0 || len(c.runtime.config.Containers.DNSOptions) > 0 { - options = c.runtime.config.Containers.DNSOptions - options = append(options, c.config.DNSOption...) - } else { - options = resolvconf.GetOptions(resolv.Content) - } + options := make([]string, 0, len(c.config.DNSOption)+len(c.runtime.config.Containers.DNSOptions)) + options = append(options, c.runtime.config.Containers.DNSOptions...) + options = append(options, c.config.DNSOption...) destPath := filepath.Join(c.state.RunDir, "resolv.conf") - if err := os.Remove(destPath); err != nil && !os.IsNotExist(err) { - return errors.Wrapf(err, "container %s", c.ID()) - } - - // Build resolv.conf - if _, err = resolvconf.Build(destPath, nameservers, search, options); err != nil { + if err := resolvconf.New(&resolvconf.Params{ + IPv6Enabled: ipv6, + KeepHostServers: keepHostServers, + Nameservers: nameservers, + Namespaces: c.config.Spec.Linux.Namespaces, + Options: options, + Path: destPath, + Searches: search, + }); err != nil { return errors.Wrapf(err, "error building resolv.conf for container %s", c.ID()) } - return c.bindMountRootFile(destPath, "/etc/resolv.conf") + return c.bindMountRootFile(destPath, resolvconf.DefaultResolvConf) } // Check if a container uses IPv6. @@ -2489,31 +2429,13 @@ func (c *Container) addNameserver(ips []string) error { } // Do we have a resolv.conf at all? - path, ok := c.state.BindMounts["/etc/resolv.conf"] + path, ok := c.state.BindMounts[resolvconf.DefaultResolvConf] if !ok { return nil } - // Read in full contents, parse out existing nameservers - contents, err := ioutil.ReadFile(path) - if err != nil { - return err - } - ns := resolvconf.GetNameservers(contents) - options := resolvconf.GetOptions(contents) - search := resolvconf.GetSearchDomains(contents) - - // We could verify that it doesn't already exist - // but extra nameservers shouldn't harm anything. - // Ensure we are the first entry in resolv.conf though, otherwise we - // might be after user-added servers. - ns = append(ips, ns...) - - // We're rewriting the container's resolv.conf as part of this, but we - // hold the container lock, so there should be no risk of parallel - // modification. - if _, err := resolvconf.Build(path, ns, search, options); err != nil { - return errors.Wrapf(err, "error adding new nameserver to container %s resolv.conf", c.ID()) + if err := resolvconf.Add(path, ips); err != nil { + return fmt.Errorf("adding new nameserver to container %s resolv.conf: %w", c.ID(), err) } return nil @@ -2528,34 +2450,13 @@ func (c *Container) removeNameserver(ips []string) error { } // Do we have a resolv.conf at all? - path, ok := c.state.BindMounts["/etc/resolv.conf"] + path, ok := c.state.BindMounts[resolvconf.DefaultResolvConf] if !ok { return nil } - // Read in full contents, parse out existing nameservers - contents, err := ioutil.ReadFile(path) - if err != nil { - return err - } - ns := resolvconf.GetNameservers(contents) - options := resolvconf.GetOptions(contents) - search := resolvconf.GetSearchDomains(contents) - - toRemove := make(map[string]bool) - for _, ip := range ips { - toRemove[ip] = true - } - - newNS := make([]string, 0, len(ns)) - for _, server := range ns { - if !toRemove[server] { - newNS = append(newNS, server) - } - } - - if _, err := resolvconf.Build(path, newNS, search, options); err != nil { - return errors.Wrapf(err, "error removing nameservers from container %s resolv.conf", c.ID()) + if err := resolvconf.Remove(path, ips); err != nil { + return fmt.Errorf("removing nameservers from container %s resolv.conf: %w", c.ID(), err) } return nil |