checker-ns-restrictions/checker/rules_ixfr.go

57 lines
1.6 KiB
Go

package checker
import (
"context"
"fmt"
sdk "git.happydns.org/checker-sdk-go/checker"
)
// ixfrRule flags nameservers that answer IXFR queries with records, which
// leaks incremental zone content to arbitrary clients.
type ixfrRule struct{}
func (r *ixfrRule) Name() string { return "ns_ixfr_refused" }
func (r *ixfrRule) Description() string {
return "Verifies that IXFR zone transfers are refused by every authoritative nameserver"
}
func (r *ixfrRule) Evaluate(ctx context.Context, obs sdk.ObservationGetter, _ sdk.CheckerOptions) []sdk.CheckState {
report, errSt := loadReport(ctx, obs, "ns_ixfr_error")
if errSt != nil {
return []sdk.CheckState{*errSt}
}
servers := probedServers(report)
if len(servers) == 0 {
return []sdk.CheckState{noProbesState("ns_ixfr_skipped")}
}
out := make([]sdk.CheckState, 0, len(servers))
for _, srv := range servers {
state := sdk.CheckState{
Subject: serverLabel(srv),
Meta: serverMeta(srv),
}
switch {
case srv.IXFR.Error != "":
state.Status = sdk.StatusOK
state.Code = "ns_ixfr_ok"
state.Message = fmt.Sprintf("query failed: %s", srv.IXFR.Error)
case srv.IXFR.Rcode != "NOERROR":
state.Status = sdk.StatusOK
state.Code = "ns_ixfr_ok"
state.Message = fmt.Sprintf("IXFR refused (rcode=%s)", srv.IXFR.Rcode)
case srv.IXFR.AnswerCount > 0:
state.Status = sdk.StatusWarn
state.Code = "ns_ixfr_accepted"
state.Message = fmt.Sprintf("IXFR accepted with %d answer(s)", srv.IXFR.AnswerCount)
default:
state.Status = sdk.StatusOK
state.Code = "ns_ixfr_ok"
state.Message = "IXFR refused or empty"
}
out = append(out, state)
}
return out
}