// Embedded DNS server has to be enabled for this sandbox. Rebuild the container's
// resolv.conf by doing the follwing
// - Save the external name servers in resolv.conf in the sandbox
// - Add only the embedded server's IP to container's resolv.conf
// - If the embedded server needs any resolv.conf options add it to the current list
func (sb *sandbox) rebuildDNS() error {
currRC, err := resolvconf.GetSpecific(sb.config.resolvConfPath)
if err != nil {
return err
}
// localhost entries have already been filtered out from the list
// retain only the v4 servers in sb for forwarding the DNS queries
sb.extDNS = resolvconf.GetNameservers(currRC.Content, types.IPv4)
var (
dnsList = []string{sb.resolver.NameServer()}
dnsOptionsList = resolvconf.GetOptions(currRC.Content)
dnsSearchList = resolvconf.GetSearchDomains(currRC.Content)
)
// external v6 DNS servers has to be listed in resolv.conf
dnsList = append(dnsList, resolvconf.GetNameservers(currRC.Content, types.IPv6)...)
// Resolver returns the options in the format resolv.conf expects
dnsOptionsList = append(dnsOptionsList, sb.resolver.ResolverOptions()...)
_, err = resolvconf.Build(sb.config.resolvConfPath, dnsList, dnsSearchList, dnsOptionsList)
return err
}
// Embedded DNS server has to be enabled for this sandbox. Rebuild the container's
// resolv.conf by doing the following
// - Save the external name servers in resolv.conf in the sandbox
// - Add only the embedded server's IP to container's resolv.conf
// - If the embedded server needs any resolv.conf options add it to the current list
func (sb *sandbox) rebuildDNS() error {
currRC, err := resolvconf.GetSpecific(sb.config.resolvConfPath)
if err != nil {
return err
}
// localhost entries have already been filtered out from the list
// retain only the v4 servers in sb for forwarding the DNS queries
sb.extDNS = resolvconf.GetNameservers(currRC.Content, types.IPv4)
var (
dnsList = []string{sb.resolver.NameServer()}
dnsOptionsList = resolvconf.GetOptions(currRC.Content)
dnsSearchList = resolvconf.GetSearchDomains(currRC.Content)
)
// external v6 DNS servers has to be listed in resolv.conf
dnsList = append(dnsList, resolvconf.GetNameservers(currRC.Content, types.IPv6)...)
// If the user config and embedded DNS server both have ndots option set,
// remember the user's config so that unqualified names not in the docker
// domain can be dropped.
resOptions := sb.resolver.ResolverOptions()
dnsOpt:
for _, resOpt := range resOptions {
if strings.Contains(resOpt, "ndots") {
for _, option := range dnsOptionsList {
if strings.Contains(option, "ndots") {
parts := strings.Split(option, ":")
if len(parts) != 2 {
return fmt.Errorf("invalid ndots option %v", option)
}
if num, err := strconv.Atoi(parts[1]); err != nil {
return fmt.Errorf("invalid number for ndots option %v", option)
} else if num > 0 {
sb.ndotsSet = true
break dnsOpt
}
}
}
}
}
dnsOptionsList = append(dnsOptionsList, resOptions...)
_, err = resolvconf.Build(sb.config.resolvConfPath, dnsList, dnsSearchList, dnsOptionsList)
return err
}
func (ep *endpoint) setupDNS() error {
ep.Lock()
container := ep.container
joinInfo := ep.joinInfo
ep.Unlock()
if container == nil {
return ErrNoContainer{}
}
if container.config.resolvConfPath == "" {
container.config.resolvConfPath = defaultPrefix + "/" + container.id + "/resolv.conf"
}
dir, _ := filepath.Split(container.config.resolvConfPath)
err := createBasePath(dir)
if err != nil {
return err
}
if joinInfo.resolvConfPath != "" {
if err := copyFile(joinInfo.resolvConfPath, container.config.resolvConfPath); err != nil {
return fmt.Errorf("could not copy source resolv.conf file %s to %s: %v", joinInfo.resolvConfPath, container.config.resolvConfPath, err)
}
return nil
}
resolvConf, err := resolvconf.Get()
if err != nil {
return err
}
if len(container.config.dnsList) > 0 ||
len(container.config.dnsSearchList) > 0 {
var (
dnsList = resolvconf.GetNameservers(resolvConf)
dnsSearchList = resolvconf.GetSearchDomains(resolvConf)
)
if len(container.config.dnsList) > 0 {
dnsList = container.config.dnsList
}
if len(container.config.dnsSearchList) > 0 {
dnsSearchList = container.config.dnsSearchList
}
return resolvconf.Build(container.config.resolvConfPath, dnsList, dnsSearchList)
}
return ep.updateDNS(resolvConf)
}
func (sb *sandbox) setupDNS() error {
if sb.config.resolvConfPath == "" {
sb.config.resolvConfPath = defaultPrefix + "/" + sb.id + "/resolv.conf"
}
sb.config.resolvConfHashFile = sb.config.resolvConfPath + ".hash"
dir, _ := filepath.Split(sb.config.resolvConfPath)
if err := createBasePath(dir); err != nil {
return err
}
// This is for the host mode networking
if sb.config.originResolvConfPath != "" {
if err := copyFile(sb.config.originResolvConfPath, sb.config.resolvConfPath); err != nil {
return fmt.Errorf("could not copy source resolv.conf file %s to %s: %v", sb.config.originResolvConfPath, sb.config.resolvConfPath, err)
}
return nil
}
resolvConf, err := resolvconf.Get()
if err != nil {
return err
}
dnsList := resolvconf.GetNameservers(resolvConf)
dnsSearchList := resolvconf.GetSearchDomains(resolvConf)
dnsOptionsList := resolvconf.GetOptions(resolvConf)
if len(sb.config.dnsList) > 0 || len(sb.config.dnsSearchList) > 0 || len(dnsOptionsList) > 0 {
if len(sb.config.dnsList) > 0 {
dnsList = sb.config.dnsList
}
if len(sb.config.dnsSearchList) > 0 {
dnsSearchList = sb.config.dnsSearchList
}
if len(sb.config.dnsOptionsList) > 0 {
dnsOptionsList = sb.config.dnsOptionsList
}
}
hash, err := resolvconf.Build(sb.config.resolvConfPath, dnsList, dnsSearchList, dnsOptionsList)
if err != nil {
return err
}
// write hash
if err := ioutil.WriteFile(sb.config.resolvConfHashFile, []byte(hash), filePerm); err != nil {
return types.InternalErrorf("failed to write resol.conf hash file when setting up dns for sandbox %s: %v", sb.ID(), err)
}
return nil
}
func (sb *sandbox) setExternalResolvers(content []byte, addrType int, checkLoopback bool) {
servers := resolvconf.GetNameservers(content, addrType)
for _, ip := range servers {
hostLoopback := false
if checkLoopback {
hostLoopback = dns.IsIPv4Localhost(ip)
}
sb.extDNS = append(sb.extDNS, extDNSEntry{
ipStr: ip,
hostLoopback: hostLoopback,
})
}
}
func (ep *endpoint) setupDNS() error {
ep.Lock()
container := ep.container
ep.Unlock()
if container == nil {
return ErrNoContainer{}
}
if container.config.resolvConfPath == "" {
container.config.resolvConfPath = defaultPrefix + "/" + container.id + "/resolv.conf"
}
dir, _ := filepath.Split(container.config.resolvConfPath)
err := createBasePath(dir)
if err != nil {
return err
}
resolvConf, err := resolvconf.Get()
if err != nil {
return err
}
if len(container.config.dnsList) > 0 ||
len(container.config.dnsSearchList) > 0 {
var (
dnsList = resolvconf.GetNameservers(resolvConf)
dnsSearchList = resolvconf.GetSearchDomains(resolvConf)
)
if len(container.config.dnsList) > 0 {
dnsList = container.config.dnsList
}
if len(container.config.dnsSearchList) > 0 {
dnsSearchList = container.config.dnsSearchList
}
return resolvconf.Build(container.config.resolvConfPath, dnsList, dnsSearchList)
}
return ep.updateDNS(resolvConf)
}
// Embedded DNS server has to be enabled for this sandbox. Rebuild the container's
// resolv.conf by doing the follwing
// - Save the external name servers in resolv.conf in the sandbox
// - Add only the embedded server's IP to container's resolv.conf
// - If the embedded server needs any resolv.conf options add it to the current list
func (sb *sandbox) rebuildDNS() error {
currRC, err := resolvconf.GetSpecific(sb.config.resolvConfPath)
if err != nil {
return err
}
// localhost entries have already been filtered out from the list
sb.extDNS = resolvconf.GetNameservers(currRC.Content)
var (
dnsList = []string{sb.resolver.NameServer()}
dnsOptionsList = resolvconf.GetOptions(currRC.Content)
dnsSearchList = resolvconf.GetSearchDomains(currRC.Content)
)
// Resolver returns the options in the format resolv.conf expects
dnsOptionsList = append(dnsOptionsList, sb.resolver.ResolverOptions()...)
dir := path.Dir(sb.config.resolvConfPath)
tmpResolvFile, err := ioutil.TempFile(dir, "resolv")
if err != nil {
return err
}
// Change the perms to filePerm (0644) since ioutil.TempFile creates it by default as 0600
if err := os.Chmod(tmpResolvFile.Name(), filePerm); err != nil {
return err
}
_, err = resolvconf.Build(tmpResolvFile.Name(), dnsList, dnsSearchList, dnsOptionsList)
if err != nil {
return err
}
return os.Rename(tmpResolvFile.Name(), sb.config.resolvConfPath)
}
func (sb *sandbox) setupDNS() error {
var newRC *resolvconf.File
if sb.config.resolvConfPath == "" {
sb.config.resolvConfPath = defaultPrefix + "/" + sb.id + "/resolv.conf"
}
sb.config.resolvConfHashFile = sb.config.resolvConfPath + ".hash"
dir, _ := filepath.Split(sb.config.resolvConfPath)
if err := createBasePath(dir); err != nil {
return err
}
// This is for the host mode networking
if sb.config.originResolvConfPath != "" {
if err := copyFile(sb.config.originResolvConfPath, sb.config.resolvConfPath); err != nil {
return fmt.Errorf("could not copy source resolv.conf file %s to %s: %v", sb.config.originResolvConfPath, sb.config.resolvConfPath, err)
}
return nil
}
currRC, err := resolvconf.Get()
if err != nil {
return err
}
if len(sb.config.dnsList) > 0 || len(sb.config.dnsSearchList) > 0 || len(sb.config.dnsOptionsList) > 0 {
var (
err error
dnsList = resolvconf.GetNameservers(currRC.Content, types.IP)
dnsSearchList = resolvconf.GetSearchDomains(currRC.Content)
dnsOptionsList = resolvconf.GetOptions(currRC.Content)
)
if len(sb.config.dnsList) > 0 {
dnsList = sb.config.dnsList
}
if len(sb.config.dnsSearchList) > 0 {
dnsSearchList = sb.config.dnsSearchList
}
if len(sb.config.dnsOptionsList) > 0 {
dnsOptionsList = sb.config.dnsOptionsList
}
newRC, err = resolvconf.Build(sb.config.resolvConfPath, dnsList, dnsSearchList, dnsOptionsList)
if err != nil {
return err
}
} else {
// Replace any localhost/127.* (at this point we have no info about ipv6, pass it as true)
if newRC, err = resolvconf.FilterResolvDNS(currRC.Content, true); err != nil {
return err
}
// No contention on container resolv.conf file at sandbox creation
if err := ioutil.WriteFile(sb.config.resolvConfPath, newRC.Content, filePerm); err != nil {
return types.InternalErrorf("failed to write unhaltered resolv.conf file content when setting up dns for sandbox %s: %v", sb.ID(), err)
}
}
// Write hash
if err := ioutil.WriteFile(sb.config.resolvConfHashFile, []byte(newRC.Hash), filePerm); err != nil {
return types.InternalErrorf("failed to write resolv.conf hash file when setting up dns for sandbox %s: %v", sb.ID(), err)
}
return nil
}
func (sb *sandbox) setupDNS() error {
var newRC *resolvconf.File
if sb.config.resolvConfPath == "" {
sb.config.resolvConfPath = defaultPrefix + "/" + sb.id + "/resolv.conf"
}
sb.config.resolvConfHashFile = sb.config.resolvConfPath + ".hash"
dir, _ := filepath.Split(sb.config.resolvConfPath)
if err := createBasePath(dir); err != nil {
return err
}
// This is for the host mode networking
if sb.config.originResolvConfPath != "" {
if err := copyFile(sb.config.originResolvConfPath, sb.config.resolvConfPath); err != nil {
return fmt.Errorf("could not copy source resolv.conf file %s to %s: %v", sb.config.originResolvConfPath, sb.config.resolvConfPath, err)
}
return nil
}
currRC, err := resolvconf.Get()
if err != nil {
return err
}
if len(sb.config.dnsList) > 0 || len(sb.config.dnsSearchList) > 0 || len(sb.config.dnsOptionsList) > 0 {
var (
err error
dnsList = resolvconf.GetNameservers(currRC.Content, types.IP)
dnsSearchList = resolvconf.GetSearchDomains(currRC.Content)
dnsOptionsList = resolvconf.GetOptions(currRC.Content)
)
if len(sb.config.dnsList) > 0 {
dnsList = sb.config.dnsList
}
if len(sb.config.dnsSearchList) > 0 {
dnsSearchList = sb.config.dnsSearchList
}
if len(sb.config.dnsOptionsList) > 0 {
dnsOptionsList = sb.config.dnsOptionsList
}
newRC, err = resolvconf.Build(sb.config.resolvConfPath, dnsList, dnsSearchList, dnsOptionsList)
if err != nil {
return err
}
// After building the resolv.conf from the user config save the
// external resolvers in the sandbox. Note that --dns 127.0.0.x
// config refers to the loopback in the container namespace
sb.setExternalResolvers(newRC.Content, types.IPv4, false)
} else {
// If the host resolv.conf file has 127.0.0.x container should
// use the host restolver for queries. This is supported by the
// docker embedded DNS server. Hence save the external resolvers
// before filtering it out.
sb.setExternalResolvers(currRC.Content, types.IPv4, true)
// Replace any localhost/127.* (at this point we have no info about ipv6, pass it as true)
if newRC, err = resolvconf.FilterResolvDNS(currRC.Content, true); err != nil {
return err
}
// No contention on container resolv.conf file at sandbox creation
if err := ioutil.WriteFile(sb.config.resolvConfPath, newRC.Content, filePerm); err != nil {
return types.InternalErrorf("failed to write unhaltered resolv.conf file content when setting up dns for sandbox %s: %v", sb.ID(), err)
}
}
// Write hash
if err := ioutil.WriteFile(sb.config.resolvConfHashFile, []byte(newRC.Hash), filePerm); err != nil {
return types.InternalErrorf("failed to write resolv.conf hash file when setting up dns for sandbox %s: %v", sb.ID(), err)
}
return nil
}