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-rw-r--r--plugin/rewrite/README.md14
-rw-r--r--plugin/rewrite/class.go3
-rw-r--r--plugin/rewrite/edns0.go23
-rw-r--r--plugin/rewrite/name.go11
-rw-r--r--plugin/rewrite/rewrite.go4
-rw-r--r--plugin/rewrite/rewrite_test.go50
-rw-r--r--plugin/rewrite/type.go3
7 files changed, 88 insertions, 20 deletions
diff --git a/plugin/rewrite/README.md b/plugin/rewrite/README.md
index 680e69722..feec7dc81 100644
--- a/plugin/rewrite/README.md
+++ b/plugin/rewrite/README.md
@@ -209,12 +209,24 @@ rewrites the first local option with code 0xffee, setting the data to "abcd". Eq
* A variable data is specified with a pair of curly brackets `{}`. Following are the supported variables:
{qname}, {qtype}, {client_ip}, {client_port}, {protocol}, {server_ip}, {server_port}.
-Example:
+* If the metadata plugin is enabled, then labels are supported as variables if they are presented within curly brackets.
+the variable data will be filled with the value associated with that label. If that label is not provided,
+the variable will be silently substitute by an empty string.
+
+Examples:
~~~
rewrite edns0 local set 0xffee {client_ip}
~~~
+The following example uses metadata and an imaginary "some-plugin" that would provide "some-label" as metadata information.
+
+~~~
+metadata
+some-plugin
+rewrite edns0 local set 0xffee {some-plugin/some-label}
+~~~
+
### EDNS0_NSID
This has no fields; it will add an NSID option with an empty string for the NSID. If the option already exists
diff --git a/plugin/rewrite/class.go b/plugin/rewrite/class.go
index d72557884..dceb4429b 100644
--- a/plugin/rewrite/class.go
+++ b/plugin/rewrite/class.go
@@ -1,6 +1,7 @@
package rewrite
import (
+ "context"
"fmt"
"strings"
@@ -29,7 +30,7 @@ func newClassRule(nextAction string, args ...string) (Rule, error) {
}
// Rewrite rewrites the the current request.
-func (rule *classRule) Rewrite(state request.Request) Result {
+func (rule *classRule) Rewrite(ctx context.Context, state request.Request) Result {
if rule.fromClass > 0 && rule.toClass > 0 {
if state.Req.Question[0].Qclass == rule.fromClass {
state.Req.Question[0].Qclass = rule.toClass
diff --git a/plugin/rewrite/edns0.go b/plugin/rewrite/edns0.go
index 68084a773..074dd3ebf 100644
--- a/plugin/rewrite/edns0.go
+++ b/plugin/rewrite/edns0.go
@@ -2,12 +2,14 @@
package rewrite
import (
+ "context"
"encoding/hex"
"fmt"
"net"
"strconv"
"strings"
+ "github.com/coredns/coredns/plugin/metadata"
"github.com/coredns/coredns/request"
"github.com/miekg/dns"
@@ -46,7 +48,7 @@ func setupEdns0Opt(r *dns.Msg) *dns.OPT {
}
// Rewrite will alter the request EDNS0 NSID option
-func (rule *edns0NsidRule) Rewrite(state request.Request) Result {
+func (rule *edns0NsidRule) Rewrite(ctx context.Context, state request.Request) Result {
o := setupEdns0Opt(state.Req)
for _, s := range o.Option {
@@ -74,7 +76,7 @@ func (rule *edns0NsidRule) Mode() string { return rule.mode }
func (rule *edns0NsidRule) GetResponseRule() ResponseRule { return ResponseRule{} }
// Rewrite will alter the request EDNS0 local options.
-func (rule *edns0LocalRule) Rewrite(state request.Request) Result {
+func (rule *edns0LocalRule) Rewrite(ctx context.Context, state request.Request) Result {
o := setupEdns0Opt(state.Req)
for _, s := range o.Option {
@@ -174,7 +176,7 @@ func newEdns0VariableRule(mode, action, code, variable string) (*edns0VariableRu
}
// ruleData returns the data specified by the variable.
-func (rule *edns0VariableRule) ruleData(state request.Request) ([]byte, error) {
+func (rule *edns0VariableRule) ruleData(ctx context.Context, state request.Request) ([]byte, error) {
switch rule.variable {
case queryName:
@@ -199,12 +201,17 @@ func (rule *edns0VariableRule) ruleData(state request.Request) ([]byte, error) {
return []byte(state.Proto()), nil
}
+ fetcher := metadata.ValueFunc(ctx, rule.variable[1:len(rule.variable)-1])
+ if fetcher != nil {
+ return []byte(fetcher()), nil
+ }
+
return nil, fmt.Errorf("unable to extract data for variable %s", rule.variable)
}
// Rewrite will alter the request EDNS0 local options with specified variables.
-func (rule *edns0VariableRule) Rewrite(state request.Request) Result {
- data, err := rule.ruleData(state)
+func (rule *edns0VariableRule) Rewrite(ctx context.Context, state request.Request) Result {
+ data, err := rule.ruleData(ctx, state)
if err != nil || data == nil {
return RewriteIgnored
}
@@ -249,6 +256,10 @@ func isValidVariable(variable string) bool {
serverPort:
return true
}
+ // we cannot validate the labels of metadata - but we can verify it has the syntax of a label
+ if strings.HasPrefix(variable, "{") && strings.HasSuffix(variable, "}") && metadata.IsLabel(variable[1:len(variable)-1]) {
+ return true
+ }
return false
}
@@ -310,7 +321,7 @@ func (rule *edns0SubnetRule) fillEcsData(state request.Request, ecs *dns.EDNS0_S
}
// Rewrite will alter the request EDNS0 subnet option.
-func (rule *edns0SubnetRule) Rewrite(state request.Request) Result {
+func (rule *edns0SubnetRule) Rewrite(ctx context.Context, state request.Request) Result {
o := setupEdns0Opt(state.Req)
for _, s := range o.Option {
diff --git a/plugin/rewrite/name.go b/plugin/rewrite/name.go
index 45e67267d..816b6cdf7 100644
--- a/plugin/rewrite/name.go
+++ b/plugin/rewrite/name.go
@@ -1,6 +1,7 @@
package rewrite
import (
+ "context"
"fmt"
"regexp"
"strconv"
@@ -56,7 +57,7 @@ const (
// Rewrite rewrites the current request based upon exact match of the name
// in the question section of the request.
-func (rule *nameRule) Rewrite(state request.Request) Result {
+func (rule *nameRule) Rewrite(ctx context.Context, state request.Request) Result {
if rule.From == state.Name() {
state.Req.Question[0].Name = rule.To
return RewriteDone
@@ -65,7 +66,7 @@ func (rule *nameRule) Rewrite(state request.Request) Result {
}
// Rewrite rewrites the current request when the name begins with the matching string.
-func (rule *prefixNameRule) Rewrite(state request.Request) Result {
+func (rule *prefixNameRule) Rewrite(ctx context.Context, state request.Request) Result {
if strings.HasPrefix(state.Name(), rule.Prefix) {
state.Req.Question[0].Name = rule.Replacement + strings.TrimLeft(state.Name(), rule.Prefix)
return RewriteDone
@@ -74,7 +75,7 @@ func (rule *prefixNameRule) Rewrite(state request.Request) Result {
}
// Rewrite rewrites the current request when the name ends with the matching string.
-func (rule *suffixNameRule) Rewrite(state request.Request) Result {
+func (rule *suffixNameRule) Rewrite(ctx context.Context, state request.Request) Result {
if strings.HasSuffix(state.Name(), rule.Suffix) {
state.Req.Question[0].Name = strings.TrimRight(state.Name(), rule.Suffix) + rule.Replacement
return RewriteDone
@@ -84,7 +85,7 @@ func (rule *suffixNameRule) Rewrite(state request.Request) Result {
// Rewrite rewrites the current request based upon partial match of the
// name in the question section of the request.
-func (rule *substringNameRule) Rewrite(state request.Request) Result {
+func (rule *substringNameRule) Rewrite(ctx context.Context, state request.Request) Result {
if strings.Contains(state.Name(), rule.Substring) {
state.Req.Question[0].Name = strings.Replace(state.Name(), rule.Substring, rule.Replacement, -1)
return RewriteDone
@@ -94,7 +95,7 @@ func (rule *substringNameRule) Rewrite(state request.Request) Result {
// Rewrite rewrites the current request when the name in the question
// section of the request matches a regular expression.
-func (rule *regexNameRule) Rewrite(state request.Request) Result {
+func (rule *regexNameRule) Rewrite(ctx context.Context, state request.Request) Result {
regexGroups := rule.Pattern.FindStringSubmatch(state.Name())
if len(regexGroups) == 0 {
return RewriteIgnored
diff --git a/plugin/rewrite/rewrite.go b/plugin/rewrite/rewrite.go
index 7389c68eb..b4bdd5e20 100644
--- a/plugin/rewrite/rewrite.go
+++ b/plugin/rewrite/rewrite.go
@@ -42,7 +42,7 @@ func (rw Rewrite) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg
state := request.Request{W: w, Req: r}
for _, rule := range rw.Rules {
- switch result := rule.Rewrite(state); result {
+ switch result := rule.Rewrite(ctx, state); result {
case RewriteDone:
respRule := rule.GetResponseRule()
if respRule.Active == true {
@@ -71,7 +71,7 @@ func (rw Rewrite) Name() string { return "rewrite" }
// Rule describes a rewrite rule.
type Rule interface {
// Rewrite rewrites the current request.
- Rewrite(state request.Request) Result
+ Rewrite(ctx context.Context, state request.Request) Result
// Mode returns the processing mode stop or continue.
Mode() string
// GetResponseRule returns the rule to rewrite response with, if any.
diff --git a/plugin/rewrite/rewrite_test.go b/plugin/rewrite/rewrite_test.go
index d67f8d0bf..f70933c3c 100644
--- a/plugin/rewrite/rewrite_test.go
+++ b/plugin/rewrite/rewrite_test.go
@@ -7,8 +7,10 @@ import (
"testing"
"github.com/coredns/coredns/plugin"
+ "github.com/coredns/coredns/plugin/metadata"
"github.com/coredns/coredns/plugin/pkg/dnstest"
"github.com/coredns/coredns/plugin/test"
+ "github.com/coredns/coredns/request"
"github.com/miekg/dns"
)
@@ -434,12 +436,32 @@ func optsEqual(a, b []dns.EDNS0) bool {
return true
}
+type testProvider map[string]metadata.Func
+
+func (tp testProvider) Metadata(ctx context.Context, state request.Request) context.Context {
+ for k, v := range tp {
+ metadata.SetValueFunc(ctx, k, v)
+ }
+ return ctx
+}
+
func TestRewriteEDNS0LocalVariable(t *testing.T) {
rw := Rewrite{
Next: plugin.HandlerFunc(msgPrinter),
noRevert: true,
}
+ expectedMetadata := []metadata.Provider{
+ testProvider{"test/label": func() string { return "my-value" }},
+ testProvider{"test/empty": func() string { return "" }},
+ }
+
+ meta := metadata.Metadata{
+ Zones: []string{"."},
+ Providers: expectedMetadata,
+ Next: &rw,
+ }
+
// test.ResponseWriter has the following values:
// The remote will always be 10.240.0.1 and port 40212.
// The local address is always 127.0.0.1 and port 53.
@@ -492,9 +514,26 @@ func TestRewriteEDNS0LocalVariable(t *testing.T) {
[]dns.EDNS0{&dns.EDNS0_LOCAL{Code: 0xffee, Data: []byte{0x7F, 0x00, 0x00, 0x01}}},
true,
},
+ {
+ []dns.EDNS0{},
+ []string{"local", "set", "0xffee", "{test/label}"},
+ []dns.EDNS0{&dns.EDNS0_LOCAL{Code: 0xffee, Data: []byte("my-value")}},
+ true,
+ },
+ {
+ []dns.EDNS0{},
+ []string{"local", "set", "0xffee", "{test/empty}"},
+ []dns.EDNS0{&dns.EDNS0_LOCAL{Code: 0xffee, Data: []byte("")}},
+ true,
+ },
+ {
+ []dns.EDNS0{},
+ []string{"local", "set", "0xffee", "{test/does-not-exist}"},
+ nil,
+ false,
+ },
}
- ctx := context.TODO()
for i, tc := range tests {
m := new(dns.Msg)
m.SetQuestion("example.com.", dns.TypeA)
@@ -506,16 +545,19 @@ func TestRewriteEDNS0LocalVariable(t *testing.T) {
}
rw.Rules = []Rule{r}
+ ctx := context.TODO()
rec := dnstest.NewRecorder(&test.ResponseWriter{})
- rw.ServeDNS(ctx, rec, m)
+ meta.ServeDNS(ctx, rec, m)
resp := rec.Msg
o := resp.IsEdns0()
- o.SetDo(tc.doBool)
if o == nil {
- t.Errorf("Test %d: EDNS0 options not set", i)
+ if tc.toOpts != nil {
+ t.Errorf("Test %d: EDNS0 options not set", i)
+ }
continue
}
+ o.SetDo(tc.doBool)
if o.Do() != tc.doBool {
t.Errorf("Test %d: Expected %v but got %v", i, tc.doBool, o.Do())
}
diff --git a/plugin/rewrite/type.go b/plugin/rewrite/type.go
index 5aa0aeae7..eebb1c02e 100644
--- a/plugin/rewrite/type.go
+++ b/plugin/rewrite/type.go
@@ -2,6 +2,7 @@
package rewrite
import (
+ "context"
"fmt"
"strings"
@@ -30,7 +31,7 @@ func newTypeRule(nextAction string, args ...string) (Rule, error) {
}
// Rewrite rewrites the the current request.
-func (rule *typeRule) Rewrite(state request.Request) Result {
+func (rule *typeRule) Rewrite(ctx context.Context, state request.Request) Result {
if rule.fromType > 0 && rule.toType > 0 {
if state.QType() == rule.fromType {
state.Req.Question[0].Qtype = rule.toType
generated by cgit v1.2.3 (git 2.39.1) at 2025-08-01 09:04:41 +0000