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|
package forward
import (
"fmt"
"strconv"
"time"
"github.com/coredns/caddy"
"github.com/coredns/coredns/core/dnsserver"
"github.com/coredns/coredns/plugin"
"github.com/coredns/coredns/plugin/dnstap"
pkgtls "github.com/coredns/coredns/plugin/pkg/tls"
)
func init() { plugin.Register("forward", setup) }
func setup(c *caddy.Controller) error {
f, err := parseForward(c)
if err != nil {
return plugin.Error("forward", err)
}
if f.Len() > max {
return plugin.Error("forward", fmt.Errorf("more than %d TOs configured: %d", max, f.Len()))
}
dnsserver.GetConfig(c).AddPlugin(func(next plugin.Handler) plugin.Handler {
f.Next = next
return f
})
c.OnStartup(func() error {
return f.OnStartup()
})
c.OnStartup(func() error {
if taph := dnsserver.GetConfig(c).Handler("dnstap"); taph != nil {
if tapPlugin, ok := taph.(dnstap.Dnstap); ok {
f.tapPlugin = &tapPlugin
}
}
return nil
})
c.OnShutdown(func() error {
return f.OnShutdown()
})
return nil
}
// OnStartup starts a goroutines for all proxies.
func (f *Forward) OnStartup() (err error) {
for _, p := range f.proxies {
p.start(f.hcInterval)
}
return nil
}
// OnShutdown stops all configured proxies.
func (f *Forward) OnShutdown() error {
for _, p := range f.proxies {
p.stop()
}
return nil
}
func parseForward(c *caddy.Controller) (*Forward, error) {
var (
f *Forward
err error
i int
)
for c.Next() {
if i > 0 {
return nil, plugin.ErrOnce
}
i++
f, err = parseStanza(c)
if err != nil {
return nil, err
}
}
return f, nil
}
func parseStanza(c *caddy.Controller) (*Forward, error) {
cfg := ForwardConfig{}
if !c.Args(&cfg.From) {
return nil, c.ArgErr()
}
cfg.To = c.RemainingArgs()
if len(cfg.To) == 0 {
return nil, c.ArgErr()
}
for c.NextBlock() {
if err := parseBlock(c, &cfg); err != nil {
return nil, err
}
}
return NewWithConfig(cfg)
}
func parseBlock(c *caddy.Controller, cfg *ForwardConfig) error {
switch c.Val() {
case "except":
cfg.Except = c.RemainingArgs()
if len(cfg.Except) == 0 {
return c.ArgErr()
}
case "max_fails":
if !c.NextArg() {
return c.ArgErr()
}
n, err := strconv.ParseInt(c.Val(), 10, 32)
if err != nil {
return err
}
if n < 0 {
return fmt.Errorf("max_fails can't be negative: %d", n)
}
maxFails := uint32(n)
cfg.MaxFails = &maxFails
case "health_check":
if !c.NextArg() {
return c.ArgErr()
}
dur, err := time.ParseDuration(c.Val())
if err != nil {
return err
}
cfg.HealthCheck = &dur
for c.NextArg() {
switch hcOpts := c.Val(); hcOpts {
case "no_rec":
cfg.HealthCheckNoRec = true
default:
return fmt.Errorf("health_check: unknown option %s", hcOpts)
}
}
case "force_tcp":
if c.NextArg() {
return c.ArgErr()
}
cfg.ForceTCP = true
case "prefer_udp":
if c.NextArg() {
return c.ArgErr()
}
cfg.PreferUDP = true
case "tls":
args := c.RemainingArgs()
if len(args) > 3 {
return c.ArgErr()
}
tlsConfig, err := pkgtls.NewTLSConfigFromArgs(args...)
if err != nil {
return err
}
cfg.TLSConfig = tlsConfig
case "tls_servername":
if !c.NextArg() {
return c.ArgErr()
}
cfg.TLSServerName = c.Val()
case "expire":
if !c.NextArg() {
return c.ArgErr()
}
dur, err := time.ParseDuration(c.Val())
if err != nil {
return err
}
cfg.Expire = &dur
case "policy":
if !c.NextArg() {
return c.ArgErr()
}
cfg.Policy = c.Val()
case "max_concurrent":
if !c.NextArg() {
return c.ArgErr()
}
n, err := strconv.Atoi(c.Val())
if err != nil {
return err
}
maxConcurrent := int64(n)
cfg.MaxConcurrent = &maxConcurrent
default:
return c.Errf("unknown property '%s'", c.Val())
}
return nil
}
const max = 15 // Maximum number of upstreams.
|
