mirror of
https://github.com/coredns/coredns.git
synced 2025-10-29 01:04:15 -04:00
e49ca86ce4
* cleanup: go vet and golint run Various cleanups trickered by go vet and golint. * Fix tests and lowercase all errors Lowercase all errors, some tests in kubernetes use errors from kubernetes which do start with a capital letter.
87 lines
2.2 KiB
Go
87 lines
2.2 KiB
Go
package rewrite
|
|
|
|
import (
|
|
"fmt"
|
|
"strings"
|
|
|
|
"github.com/coredns/coredns/middleware"
|
|
|
|
"github.com/miekg/dns"
|
|
|
|
"golang.org/x/net/context"
|
|
)
|
|
|
|
// Result is the result of a rewrite
|
|
type Result int
|
|
|
|
const (
|
|
// RewriteIgnored is returned when rewrite is not done on request.
|
|
RewriteIgnored Result = iota
|
|
// RewriteDone is returned when rewrite is done on request.
|
|
RewriteDone
|
|
// RewriteStatus is returned when rewrite is not needed and status code should be set
|
|
// for the request.
|
|
RewriteStatus
|
|
)
|
|
|
|
// Rewrite is middleware to rewrite requests internally before being handled.
|
|
type Rewrite struct {
|
|
Next middleware.Handler
|
|
Rules []Rule
|
|
noRevert bool
|
|
}
|
|
|
|
// ServeDNS implements the middleware.Handler interface.
|
|
func (rw Rewrite) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
|
|
wr := NewResponseReverter(w, r)
|
|
for _, rule := range rw.Rules {
|
|
switch result := rule.Rewrite(r); result {
|
|
case RewriteDone:
|
|
if rw.noRevert {
|
|
return middleware.NextOrFailure(rw.Name(), rw.Next, ctx, w, r)
|
|
}
|
|
return middleware.NextOrFailure(rw.Name(), rw.Next, ctx, wr, r)
|
|
case RewriteIgnored:
|
|
break
|
|
case RewriteStatus:
|
|
// only valid for complex rules.
|
|
// if cRule, ok := rule.(*ComplexRule); ok && cRule.Status != 0 {
|
|
// return cRule.Status, nil
|
|
// }
|
|
}
|
|
}
|
|
return middleware.NextOrFailure(rw.Name(), rw.Next, ctx, w, r)
|
|
}
|
|
|
|
// Name implements the Handler interface.
|
|
func (rw Rewrite) Name() string { return "rewrite" }
|
|
|
|
// Rule describes a rewrite rule.
|
|
type Rule interface {
|
|
// Rewrite rewrites the current request.
|
|
Rewrite(*dns.Msg) Result
|
|
}
|
|
|
|
func newRule(args ...string) (Rule, error) {
|
|
if len(args) == 0 {
|
|
return nil, fmt.Errorf("no rule type specified for rewrite")
|
|
}
|
|
|
|
ruleType := strings.ToLower(args[0])
|
|
if ruleType != "edns0" && len(args) != 3 {
|
|
return nil, fmt.Errorf("%s rules must have exactly two arguments", ruleType)
|
|
}
|
|
switch ruleType {
|
|
case "name":
|
|
return newNameRule(args[1], args[2])
|
|
case "class":
|
|
return newClassRule(args[1], args[2])
|
|
case "type":
|
|
return newTypeRule(args[1], args[2])
|
|
case "edns0":
|
|
return newEdns0Rule(args[1:]...)
|
|
default:
|
|
return nil, fmt.Errorf("invalid rule type %q", args[0])
|
|
}
|
|
}
|