Pierre-Olivier Mercier
7e50f404a1
Generic SRV records checker for happyDomain.
For each SRV record attached to an svcs.UnknownSRV service, the checker
resolves every target and probes reachability:
- DNS resolution (A/AAAA), CNAME detection (RFC 2782 violation),
null-target detection (RFC 2782 "service explicitly unavailable")
- TCP connect to target:port for _tcp SRVs
- UDP probe for _udp SRVs, using ICMP port-unreachable detection
The checker also publishes TLS endpoints (host, port, SNI) for every
SRV target hitting a well-known direct-TLS port (443, 465, 636, 853,
993, 995, 5061, 5223, …) via the EndpointDiscoverer SDK interface, so
a downstream TLS checker can pick them up.
The HTML report groups records as cards and surfaces the most common
failure scenarios (DNS failure, CNAME target, TCP unreachable,
null-target) at the top with remediation guidance.
52 lines
1.1 KiB
Go
52 lines
1.1 KiB
Go
package checker
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import (
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"context"
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"fmt"
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sdk "git.happydns.org/checker-sdk-go/checker"
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)
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// One rule per concern so each failure is individually visible rather than buried in a single rule's Code field.
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func Rules() []sdk.CheckRule {
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return []sdk.CheckRule{
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RulePresent(),
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RuleNullTarget(),
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RuleTargetNotCNAME(),
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RuleTargetsResolve(),
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RuleTCPReachable(),
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RuleUDPReachable(),
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RulePortValid(),
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RulePriorityWeightSanity(),
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RuleRedundancy(),
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}
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}
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func getData(ctx context.Context, obs sdk.ObservationGetter) (*SRVData, *sdk.CheckState) {
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var d SRVData
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if err := obs.Get(ctx, ObservationKeySRV, &d); err != nil {
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return nil, &sdk.CheckState{
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Status: sdk.StatusError,
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Message: fmt.Sprintf("Failed to load SRV observation: %v", err),
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Code: "srv_obs_error",
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}
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}
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return &d, nil
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}
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func countProbeResults(d *SRVData, proto string) (total, ok int, failed []string) {
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for _, r := range d.Records {
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if r.IsNullTarget || r.Proto != proto {
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continue
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}
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for _, pr := range r.Probes {
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total++
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if pr.Connected {
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ok++
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} else {
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failed = append(failed, fmt.Sprintf("%s: %s", pr.Address, pr.Error))
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}
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}
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}
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return
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}
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