43 lines
1 KiB
Go
43 lines
1 KiB
Go
package rewrite
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import (
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"fmt"
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"strings"
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"github.com/miekg/dns"
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)
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type classRule struct {
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fromClass uint16
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toClass uint16
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NextAction string
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}
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// newClassRule creates a class matching rule
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func newClassRule(nextAction string, args ...string) (Rule, error) {
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var from, to uint16
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var ok bool
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if from, ok = dns.StringToClass[strings.ToUpper(args[0])]; !ok {
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return nil, fmt.Errorf("invalid class %q", strings.ToUpper(args[0]))
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}
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if to, ok = dns.StringToClass[strings.ToUpper(args[1])]; !ok {
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return nil, fmt.Errorf("invalid class %q", strings.ToUpper(args[1]))
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}
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return &classRule{from, to, nextAction}, nil
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}
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// Rewrite rewrites the the current request.
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func (rule *classRule) Rewrite(w dns.ResponseWriter, r *dns.Msg) Result {
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if rule.fromClass > 0 && rule.toClass > 0 {
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if r.Question[0].Qclass == rule.fromClass {
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r.Question[0].Qclass = rule.toClass
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return RewriteDone
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}
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}
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return RewriteIgnored
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}
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// Mode returns the processing mode
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func (rule *classRule) Mode() string {
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return rule.NextAction
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}
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