feat: Add core definitions for dns-account-01 (#8140)

## Summary

This PR introduces the foundational components required to support
the `dns-account-01` challenge type, as specified in draft-ietf-acme-dns-account-label-00:
https://datatracker.ietf.org/doc/draft-ietf-acme-dns-account-label/.

It focuses only on core definitions and SA support. PA/VA/RA logic will be in
a follow-up change.

Core Definitions & Logic:
- //core/objects.go: Added `ChallengeTypeDNSAccount01` constant and
  updated validation methods
- //core/challenges.go: Added `DNSAccountChallenge01` constructor
  and factory support

Storage Authority (SA) Support:
- //sa/model.go: Added `dns-account-01` to challenge type mappings

Testing:
- //core/*_test.go: Basic definition and validation tests
- //sa/sa_test.go: Database round-trip tests for `dns-account-01`
  challenges

Dependencies:
- Updated github.com/eggsampler/acme/v3 to release version v3.6.2

Author: sheurich

core/challenges.go

@@ -25,6 +25,11 @@ func TLSALPNChallenge01(token string) Challenge {
 	return newChallenge(ChallengeTypeTLSALPN01, token)
 }
 
+// DNSAccountChallenge01 constructs a dns-account-01 challenge.
+func DNSAccountChallenge01(token string) Challenge {
+	return newChallenge(ChallengeTypeDNSAccount01, token)
+}
+
 // NewChallenge constructs a challenge of the given kind. It returns an
 // error if the challenge type is unrecognized.
 func NewChallenge(kind AcmeChallenge, token string) (Challenge, error) {
@@ -35,6 +40,8 @@ func NewChallenge(kind AcmeChallenge, token string) (Challenge, error) {
 		return DNSChallenge01(token), nil
 	case ChallengeTypeTLSALPN01:
 		return TLSALPNChallenge01(token), nil
+	case ChallengeTypeDNSAccount01:
+		return DNSAccountChallenge01(token), nil
 	default:
 		return Challenge{}, fmt.Errorf("unrecognized challenge type %q", kind)
 	}

core/core_test.go

@@ -32,12 +32,16 @@ func TestChallenges(t *testing.T) {
 	dns01 := DNSChallenge01(token)
 	test.AssertNotError(t, dns01.CheckPending(), "CheckConsistencyForClientOffer returned an error")
 
+	dnsAccount01 := DNSAccountChallenge01(token)
+	test.AssertNotError(t, dnsAccount01.CheckPending(), "CheckConsistencyForClientOffer returned an error")
+
 	tlsalpn01 := TLSALPNChallenge01(token)
 	test.AssertNotError(t, tlsalpn01.CheckPending(), "CheckConsistencyForClientOffer returned an error")
 
 	test.Assert(t, ChallengeTypeHTTP01.IsValid(), "Refused valid challenge")
 	test.Assert(t, ChallengeTypeDNS01.IsValid(), "Refused valid challenge")
 	test.Assert(t, ChallengeTypeTLSALPN01.IsValid(), "Refused valid challenge")
+	test.Assert(t, ChallengeTypeDNSAccount01.IsValid(), "Refused valid challenge")
 	test.Assert(t, !AcmeChallenge("nonsense-71").IsValid(), "Accepted invalid challenge")
 }
 

core/objects.go

@@ -53,15 +53,16 @@ type AcmeChallenge string
 
 // These types are the available challenges
 const (
-	ChallengeTypeHTTP01    = AcmeChallenge("http-01")
-	ChallengeTypeDNS01     = AcmeChallenge("dns-01")
-	ChallengeTypeTLSALPN01 = AcmeChallenge("tls-alpn-01")
+	ChallengeTypeHTTP01       = AcmeChallenge("http-01")
+	ChallengeTypeDNS01        = AcmeChallenge("dns-01")
+	ChallengeTypeTLSALPN01    = AcmeChallenge("tls-alpn-01")
+	ChallengeTypeDNSAccount01 = AcmeChallenge("dns-account-01")
 )
 
 // IsValid tests whether the challenge is a known challenge
 func (c AcmeChallenge) IsValid() bool {
 	switch c {
-	case ChallengeTypeHTTP01, ChallengeTypeDNS01, ChallengeTypeTLSALPN01:
+	case ChallengeTypeHTTP01, ChallengeTypeDNS01, ChallengeTypeTLSALPN01, ChallengeTypeDNSAccount01:
 		return true
 	default:
 		return false
@@ -228,7 +229,7 @@ func (ch Challenge) RecordsSane() bool {
 			(ch.ValidationRecord[0].AddressUsed == netip.Addr{}) || len(ch.ValidationRecord[0].AddressesResolved) == 0 {
 			return false
 		}
-	case ChallengeTypeDNS01:
+	case ChallengeTypeDNS01, ChallengeTypeDNSAccount01:
 		if len(ch.ValidationRecord) > 1 {
 			return false
 		}

core/objects_test.go

@@ -59,7 +59,7 @@ func TestChallengeSanityCheck(t *testing.T) {
   }`), &accountKey)
 	test.AssertNotError(t, err, "Error unmarshaling JWK")
 
-	types := []AcmeChallenge{ChallengeTypeHTTP01, ChallengeTypeDNS01, ChallengeTypeTLSALPN01}
+	types := []AcmeChallenge{ChallengeTypeHTTP01, ChallengeTypeDNS01, ChallengeTypeTLSALPN01, ChallengeTypeDNSAccount01}
 	for _, challengeType := range types {
 		chall := Challenge{
 			Type:   challengeType,
@@ -152,6 +152,8 @@ func TestChallengeStringID(t *testing.T) {
 	test.AssertEquals(t, ch.StringID(), "iFVMwA")
 	ch.Type = ChallengeTypeHTTP01
 	test.AssertEquals(t, ch.StringID(), "0Gexug")
+	ch.Type = ChallengeTypeDNSAccount01
+	test.AssertEquals(t, ch.StringID(), "8z2wSg")
 }
 
 func TestFindChallengeByType(t *testing.T) {

go.mod

@@ -7,7 +7,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/config v1.29.17
 	github.com/aws/aws-sdk-go-v2/service/s3 v1.83.0
 	github.com/aws/smithy-go v1.22.4
-	github.com/eggsampler/acme/v3 v3.6.2-0.20250208073118-0466a0230941
+	github.com/eggsampler/acme/v3 v3.6.2
 	github.com/go-jose/go-jose/v4 v4.1.0
 	github.com/go-logr/stdr v1.2.2
 	github.com/go-sql-driver/mysql v1.9.1

go.sum

@@ -70,8 +70,8 @@ github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZm
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
-github.com/eggsampler/acme/v3 v3.6.2-0.20250208073118-0466a0230941 h1:CnQwymLMJ3MSfjbZQ/bpaLfuXBZuM3LUgAHJ0gO/7d8=
-github.com/eggsampler/acme/v3 v3.6.2-0.20250208073118-0466a0230941/go.mod h1:/qh0rKC/Dh7Jj+p4So7DbWmFNzC4dpcpK53r226Fhuo=
+github.com/eggsampler/acme/v3 v3.6.2 h1:gvyZbQ92wNQLDASVftGpHEdFwPSfg0+17P0lLt09Tp8=
+github.com/eggsampler/acme/v3 v3.6.2/go.mod h1:/qh0rKC/Dh7Jj+p4So7DbWmFNzC4dpcpK53r226Fhuo=
 github.com/fatih/color v1.9.0/go.mod h1:eQcE1qtQxscV5RaZvpXrrb8Drkc3/DdQ+uUYCNjL+zU=
 github.com/felixge/httpsnoop v1.0.4 h1:NFTV2Zj1bL4mc9sqWACXbQFVBBg2W3GPvqp8/ESS2Wg=
 github.com/felixge/httpsnoop v1.0.4/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=

sa/model.go

@@ -416,15 +416,17 @@ func modelToOrder(om *orderModel) (*corepb.Order, error) {
 }
 
 var challTypeToUint = map[string]uint8{
-	"http-01":     0,
-	"dns-01":      1,
-	"tls-alpn-01": 2,
+	"http-01":        0,
+	"dns-01":         1,
+	"tls-alpn-01":    2,
+	"dns-account-01": 3,
 }
 
 var uintToChallType = map[uint8]string{
 	0: "http-01",
 	1: "dns-01",
 	2: "tls-alpn-01",
+	3: "dns-account-01",
 }
 
 var identifierTypeToUint = map[string]uint8{

sa/sa_test.go

@@ -2632,6 +2632,36 @@ func TestGetValidAuthorizations2(t *testing.T) {
 		aaa = am.ID
 	}
 
+	var dac int64
+	{
+		tokenStr := core.NewToken()
+		token, err := base64.RawURLEncoding.DecodeString(tokenStr)
+		test.AssertNotError(t, err, "computing test authorization challenge token")
+
+		profile := "test"
+		attempted := challTypeToUint[string(core.ChallengeTypeDNSAccount01)]
+		attemptedAt := fc.Now()
+		vr, _ := json.Marshal([]core.ValidationRecord{})
+
+		am := authzModel{
+			IdentifierType:         identifierTypeToUint[string(identifier.TypeDNS)],
+			IdentifierValue:        "aaa",
+			RegistrationID:         3,
+			CertificateProfileName: &profile,
+			Status:                 statusToUint[core.StatusValid],
+			Expires:                fc.Now().Add(24 * time.Hour),
+			Challenges:             1 << challTypeToUint[string(core.ChallengeTypeDNSAccount01)],
+			Attempted:              &attempted,
+			AttemptedAt:            &attemptedAt,
+			Token:                  token,
+			ValidationError:        nil,
+			ValidationRecord:       vr,
+		}
+		err = sa.dbMap.Insert(context.Background(), &am)
+		test.AssertNotError(t, err, "failed to insert valid authz with dns-account-01")
+		dac = am.ID
+	}
+
 	for _, tc := range []struct {
 		name        string
 		regID       int64
@@ -2648,6 +2678,14 @@ func TestGetValidAuthorizations2(t *testing.T) {
 			validUntil:  fc.Now().Add(time.Hour),
 			wantIDs:     []int64{aaa},
 		},
+		{
+			name:        "happy path, dns-account-01 challenge",
+			regID:       3,
+			identifiers: []*corepb.Identifier{identifier.NewDNS("aaa").ToProto()},
+			profile:     "test",
+			validUntil:  fc.Now().Add(time.Hour),
+			wantIDs:     []int64{dac},
+		},
 		{
 			name:        "different identifier type",
 			regID:       1,

vendor/github.com/eggsampler/acme/v3/Makefile

@@ -140,7 +140,7 @@ github.com/cespare/xxhash/v2
 # github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f
 ## explicit
 github.com/dgryski/go-rendezvous
-# github.com/eggsampler/acme/v3 v3.6.2-0.20250208073118-0466a0230941
+# github.com/eggsampler/acme/v3 v3.6.2
 ## explicit; go 1.11
 github.com/eggsampler/acme/v3
 # github.com/felixge/httpsnoop v1.0.4