Golang resolvconf.Get函数代码示例

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
}

// FindAvailableNetwork returns a network from the passed list which does not
// overlap with existing interfaces in the system
func FindAvailableNetwork(list []*net.IPNet) (*net.IPNet, error) {
	// We don't check for an error here, because we don't really care if we
	// can't read /etc/resolv.conf. So instead we skip the append if resolvConf
	// is nil. It either doesn't exist, or we can't read it for some reason.
	var nameservers []string
	if rc, err := resolvconf.Get(); err == nil {
		nameservers = resolvconf.GetNameserversAsCIDR(rc.Content)
	}
	for _, nw := range list {
		if err := netutils.CheckNameserverOverlaps(nameservers, nw); err == nil {
			if err := netutils.CheckRouteOverlaps(nw); err == nil {
				return nw, nil
			}
		}
	}
	return nil, fmt.Errorf("no available network")
}

func isOverlap(nw *net.IPNet) bool {
	var nameservers []string

	if rc, err := resolvconf.Get(); err == nil {
		nameservers = resolvconf.GetNameserversAsCIDR(rc.Content)
	}

	if err := netutils.CheckNameserverOverlaps(nameservers, nw); err != nil {
		return true
	}

	if err := netutils.CheckRouteOverlaps(nw); err != nil {
		return true
	}

	return false
}

func checkOverlap(nw *net.IPNet) error {
	var nameservers []string

	if rc, err := resolvconf.Get(); err == nil {
		nameservers = resolvconf.GetNameserversAsCIDR(rc.Content)
	}

	if err := netutils.CheckNameserverOverlaps(nameservers, nw); err != nil {
		return fmt.Errorf("overlay subnet %s failed check with nameserver: %v: %v", nw.String(), nameservers, err)
	}

	if err := netutils.CheckRouteOverlaps(nw); err != nil {
		return fmt.Errorf("overlay subnet %s failed check with host route table: %v", nw.String(), err)
	}

	return nil
}

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)
}

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
}