forked from TrueCloudLab/distribution
a685e3fc98
Vndr has a simpler configuration and allows pointing to forked packages. Additionally other docker projects are now using vndr making vendoring in distribution more consistent. Updates letsencrypt to use fork. No longer uses sub-vendored packages. Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
99 lines
2.2 KiB
Go
99 lines
2.2 KiB
Go
package dns
|
|
|
|
import (
|
|
"bufio"
|
|
"os"
|
|
"strconv"
|
|
"strings"
|
|
)
|
|
|
|
// ClientConfig wraps the contents of the /etc/resolv.conf file.
|
|
type ClientConfig struct {
|
|
Servers []string // servers to use
|
|
Search []string // suffixes to append to local name
|
|
Port string // what port to use
|
|
Ndots int // number of dots in name to trigger absolute lookup
|
|
Timeout int // seconds before giving up on packet
|
|
Attempts int // lost packets before giving up on server, not used in the package dns
|
|
}
|
|
|
|
// ClientConfigFromFile parses a resolv.conf(5) like file and returns
|
|
// a *ClientConfig.
|
|
func ClientConfigFromFile(resolvconf string) (*ClientConfig, error) {
|
|
file, err := os.Open(resolvconf)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
defer file.Close()
|
|
c := new(ClientConfig)
|
|
scanner := bufio.NewScanner(file)
|
|
c.Servers = make([]string, 0)
|
|
c.Search = make([]string, 0)
|
|
c.Port = "53"
|
|
c.Ndots = 1
|
|
c.Timeout = 5
|
|
c.Attempts = 2
|
|
|
|
for scanner.Scan() {
|
|
if err := scanner.Err(); err != nil {
|
|
return nil, err
|
|
}
|
|
line := scanner.Text()
|
|
f := strings.Fields(line)
|
|
if len(f) < 1 {
|
|
continue
|
|
}
|
|
switch f[0] {
|
|
case "nameserver": // add one name server
|
|
if len(f) > 1 {
|
|
// One more check: make sure server name is
|
|
// just an IP address. Otherwise we need DNS
|
|
// to look it up.
|
|
name := f[1]
|
|
c.Servers = append(c.Servers, name)
|
|
}
|
|
|
|
case "domain": // set search path to just this domain
|
|
if len(f) > 1 {
|
|
c.Search = make([]string, 1)
|
|
c.Search[0] = f[1]
|
|
} else {
|
|
c.Search = make([]string, 0)
|
|
}
|
|
|
|
case "search": // set search path to given servers
|
|
c.Search = make([]string, len(f)-1)
|
|
for i := 0; i < len(c.Search); i++ {
|
|
c.Search[i] = f[i+1]
|
|
}
|
|
|
|
case "options": // magic options
|
|
for i := 1; i < len(f); i++ {
|
|
s := f[i]
|
|
switch {
|
|
case len(s) >= 6 && s[:6] == "ndots:":
|
|
n, _ := strconv.Atoi(s[6:])
|
|
if n < 1 {
|
|
n = 1
|
|
}
|
|
c.Ndots = n
|
|
case len(s) >= 8 && s[:8] == "timeout:":
|
|
n, _ := strconv.Atoi(s[8:])
|
|
if n < 1 {
|
|
n = 1
|
|
}
|
|
c.Timeout = n
|
|
case len(s) >= 8 && s[:9] == "attempts:":
|
|
n, _ := strconv.Atoi(s[9:])
|
|
if n < 1 {
|
|
n = 1
|
|
}
|
|
c.Attempts = n
|
|
case s == "rotate":
|
|
/* not imp */
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return c, nil
|
|
}
|