Casey Callendrello 5cde14cd7b ipam/host-local: add ResolvConf argument for DNS configuration
This adds the option `resolvConf` to the host-local IPAM configuration.
If specified, the plugin will try to parse the file as a resolv.conf(5)
type file and return it in the DNS response.
2017-01-11 18:48:35 +01:00

65 lines
1.5 KiB
Go

// Copyright 2016 CNI authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package main
import (
"bufio"
"os"
"strings"
"github.com/containernetworking/cni/pkg/types"
)
// parseResolvConf parses an existing resolv.conf in to a DNS struct
func parseResolvConf(filename string) (*types.DNS, error) {
fp, err := os.Open(filename)
if err != nil {
return nil, err
}
dns := types.DNS{}
scanner := bufio.NewScanner(fp)
for scanner.Scan() {
line := scanner.Text()
line = strings.TrimSpace(line)
// Skip comments, empty lines
if len(line) == 0 || line[0] == '#' || line[0] == ';' {
continue
}
fields := strings.Fields(line)
if len(fields) < 2 {
continue
}
switch fields[0] {
case "nameserver":
dns.Nameservers = append(dns.Nameservers, fields[1])
case "domain":
dns.Domain = fields[1]
case "search":
dns.Search = append(dns.Search, fields[1:]...)
case "options":
dns.Options = append(dns.Options, fields[1:]...)
}
}
if err := scanner.Err(); err != nil {
return nil, err
}
return &dns, nil
}