checker-caa/checker/tls_related.go

92 lines
2.6 KiB
Go

package checker
import (
"encoding/json"
"net"
"strconv"
"strings"
"time"
sdk "git.happydns.org/checker-sdk-go/checker"
)
// tlsProbeView is a permissive subset of checker-tls's probe payload;
// only fields the CAA rule needs are decoded so the TLS checker can
// evolve its schema independently.
type tlsProbeView struct {
Host string `json:"host,omitempty"`
Port uint16 `json:"port,omitempty"`
Endpoint string `json:"endpoint,omitempty"`
Type string `json:"type,omitempty"`
Issuer string `json:"issuer,omitempty"`
IssuerDN string `json:"issuer_dn,omitempty"`
IssuerAKI string `json:"issuer_aki,omitempty"`
NotAfter time.Time `json:"not_after,omitempty"`
ChainValid *bool `json:"chain_valid,omitempty"`
DNSNames []string `json:"dns_names,omitempty"`
Subject string `json:"subject,omitempty"`
}
// isWildcard reports whether the observed certificate covers at least
// one wildcard DNS name. Used to pick between the CAA "issue" and
// "issuewild" allow lists per RFC 8659 §4.3.
func (v *tlsProbeView) isWildcard() bool {
for _, n := range v.DNSNames {
if strings.HasPrefix(n, "*.") {
return true
}
}
return false
}
func (v *tlsProbeView) address() string {
if v.Endpoint != "" {
return v.Endpoint
}
if v.Host != "" && v.Port != 0 {
return net.JoinHostPort(v.Host, strconv.FormatUint(uint64(v.Port), 10))
}
return v.Host
}
// parseTLSRelated decodes a RelatedObservation into probes. Two
// payload shapes are accepted: the current {"probes": {ref: …}} map
// (filtered by r.Ref when set) and a bare top-level probe (back-compat).
// Returns nil when the payload is not a recognizable probe shape.
func parseTLSRelated(r sdk.RelatedObservation) []*tlsProbeView {
var keyed struct {
Probes map[string]tlsProbeView `json:"probes"`
}
if err := json.Unmarshal(r.Data, &keyed); err == nil && keyed.Probes != nil {
if r.Ref != "" {
if p, ok := keyed.Probes[r.Ref]; ok {
cp := p
return []*tlsProbeView{&cp}
}
}
out := make([]*tlsProbeView, 0, len(keyed.Probes))
for _, p := range keyed.Probes {
cp := p
out = append(out, &cp)
}
return out
}
var v tlsProbeView
if err := json.Unmarshal(r.Data, &v); err != nil {
return nil
}
if v.Host == "" && v.IssuerAKI == "" && v.IssuerDN == "" {
return nil
}
return []*tlsProbeView{&v}
}
// parseAllTLSRelated flattens a slice of RelatedObservations into one
// entry per endpoint.
func parseAllTLSRelated(related []sdk.RelatedObservation) []*tlsProbeView {
var out []*tlsProbeView
for _, r := range related {
out = append(out, parseTLSRelated(r)...)
}
return out
}