httpcaddyfile: Add missing DNS challenge check for acme_dns (#7270)

* add optional argument to `mock` DNS provider

* preserve local DNS challenge settings when `acme_dns` is specified

* add missing check for `acme_dns`

caddyconfig/httpcaddyfile/builtins.go

@@ -481,7 +481,7 @@ func parseTLS(h Helper) ([]ConfigValue, error) {
 	// Validate DNS challenge config: any DNS challenge option except "dns" requires a DNS provider
 	if acmeIssuer != nil && acmeIssuer.Challenges != nil && acmeIssuer.Challenges.DNS != nil {
 		dnsCfg := acmeIssuer.Challenges.DNS
-		providerSet := dnsCfg.ProviderRaw != nil || h.Option("dns") != nil
+		providerSet := dnsCfg.ProviderRaw != nil || h.Option("dns") != nil || h.Option("acme_dns") != nil
 		if len(dnsOptionsSet) > 0 && !providerSet {
 			return nil, h.Errf(
 				"setting DNS challenge options [%s] requires a DNS provider (set with the 'dns' subdirective or 'acme_dns' global option)",

caddyconfig/httpcaddyfile/tlsapp.go

@@ -564,23 +564,22 @@ func fillInGlobalACMEDefaults(issuer certmagic.Issuer, options map[string]any) e
 	if globalACMECARoot != nil && !slices.Contains(acmeIssuer.TrustedRootsPEMFiles, globalACMECARoot.(string)) {
 		acmeIssuer.TrustedRootsPEMFiles = append(acmeIssuer.TrustedRootsPEMFiles, globalACMECARoot.(string))
 	}
-	if globalACMEDNSok {
+	if globalACMEDNSok && (acmeIssuer.Challenges == nil || acmeIssuer.Challenges.DNS == nil || acmeIssuer.Challenges.DNS.ProviderRaw == nil) {
 		globalDNS := options["dns"]
-		if globalDNS != nil {
+		if globalDNS == nil && globalACMEDNS == nil {
-			// If global `dns` is set, do NOT set provider in issuer, just set empty dns config
-			acmeIssuer.Challenges = &caddytls.ChallengesConfig{
-				DNS: &caddytls.DNSChallengeConfig{},
-			}
-		} else if globalACMEDNS != nil {
-			// Set a global DNS provider if `acme_dns` is set and `dns` is NOT set
-			acmeIssuer.Challenges = &caddytls.ChallengesConfig{
-				DNS: &caddytls.DNSChallengeConfig{
-					ProviderRaw: caddyconfig.JSONModuleObject(globalACMEDNS, "name", globalACMEDNS.(caddy.Module).CaddyModule().ID.Name(), nil),
-				},
-			}
-		} else {
 			return fmt.Errorf("acme_dns specified without DNS provider config, but no provider specified with 'dns' global option")
 		}
+		if acmeIssuer.Challenges == nil {
+			acmeIssuer.Challenges = new(caddytls.ChallengesConfig)
+		}
+		if acmeIssuer.Challenges.DNS == nil {
+			acmeIssuer.Challenges.DNS = new(caddytls.DNSChallengeConfig)
+		}
+		// If global `dns` is set, do NOT set provider in issuer, just set empty dns config
+		if globalDNS == nil && acmeIssuer.Challenges.DNS.ProviderRaw == nil {
+			// Set a global DNS provider if `acme_dns` is set and `dns` is NOT set
+			acmeIssuer.Challenges.DNS.ProviderRaw = caddyconfig.JSONModuleObject(globalACMEDNS, "name", globalACMEDNS.(caddy.Module).CaddyModule().ID.Name(), nil)
+		}
 	}
 	if globalACMEEAB != nil && acmeIssuer.ExternalAccount == nil {
 		acmeIssuer.ExternalAccount = globalACMEEAB.(*acme.EAB)

caddytest/integration/caddyfile_adapt/acme_dns_configured.caddyfiletest

@@ -53,6 +53,7 @@ example.com {
 								"challenges": {
 									"dns": {
 										"provider": {
+											"argument": "foo",
 											"name": "mock"
 										}
 									}

caddytest/integration/caddyfile_adapt/tls_dns_override_acme_dns.caddyfiletest

@@ -0,0 +1,79 @@
+{
+	acme_dns mock foo
+}
+
+localhost {
+	tls {
+		dns mock bar
+		resolvers 8.8.8.8 8.8.4.4
+	}
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":443"
+					],
+					"routes": [
+						{
+							"match": [
+								{
+									"host": [
+										"localhost"
+									]
+								}
+							],
+							"terminal": true
+						}
+					]
+				}
+			}
+		},
+		"tls": {
+			"automation": {
+				"policies": [
+					{
+						"subjects": [
+							"localhost"
+						],
+						"issuers": [
+							{
+								"challenges": {
+									"dns": {
+										"provider": {
+											"argument": "bar",
+											"name": "mock"
+										},
+										"resolvers": [
+											"8.8.8.8",
+											"8.8.4.4"
+										]
+									}
+								},
+								"module": "acme"
+							}
+						]
+					},
+					{
+						"issuers": [
+							{
+								"challenges": {
+									"dns": {
+										"provider": {
+											"argument": "foo",
+											"name": "mock"
+										}
+									}
+								},
+								"module": "acme"
+							}
+						]
+					}
+				]
+			}
+		}
+	}
+}

caddytest/integration/caddyfile_adapt/tls_dns_override_global_dns.caddyfiletest

@@ -0,0 +1,68 @@
+{
+	dns mock foo
+}
+
+localhost {
+	tls {
+		dns mock bar
+		resolvers 8.8.8.8 8.8.4.4
+	}
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":443"
+					],
+					"routes": [
+						{
+							"match": [
+								{
+									"host": [
+										"localhost"
+									]
+								}
+							],
+							"terminal": true
+						}
+					]
+				}
+			}
+		},
+		"tls": {
+			"automation": {
+				"policies": [
+					{
+						"subjects": [
+							"localhost"
+						],
+						"issuers": [
+							{
+								"challenges": {
+									"dns": {
+										"provider": {
+											"argument": "bar",
+											"name": "mock"
+										},
+										"resolvers": [
+											"8.8.8.8",
+											"8.8.4.4"
+										]
+									}
+								},
+								"module": "acme"
+							}
+						]
+					}
+				]
+			},
+			"dns": {
+				"argument": "foo",
+				"name": "mock"
+			}
+		}
+	}
+}

caddytest/integration/caddyfile_adapt/tls_dns_resolvers_with_global_provider.caddyfiletest

@@ -0,0 +1,76 @@
+{
+	acme_dns mock
+}
+
+localhost {
+	tls {
+		resolvers 8.8.8.8 8.8.4.4
+	}
+}
+----------
+{
+	"apps": {
+		"http": {
+			"servers": {
+				"srv0": {
+					"listen": [
+						":443"
+					],
+					"routes": [
+						{
+							"match": [
+								{
+									"host": [
+										"localhost"
+									]
+								}
+							],
+							"terminal": true
+						}
+					]
+				}
+			}
+		},
+		"tls": {
+			"automation": {
+				"policies": [
+					{
+						"subjects": [
+							"localhost"
+						],
+						"issuers": [
+							{
+								"challenges": {
+									"dns": {
+										"provider": {
+											"name": "mock"
+										},
+										"resolvers": [
+											"8.8.8.8",
+											"8.8.4.4"
+										]
+									}
+								},
+								"module": "acme"
+							}
+						]
+					},
+					{
+						"issuers": [
+							{
+								"challenges": {
+									"dns": {
+										"provider": {
+											"name": "mock"
+										}
+									}
+								},
+								"module": "acme"
+							}
+						]
+					}
+				]
+			}
+		}
+	}
+}

caddytest/integration/mockdns_test.go

@@ -15,7 +15,9 @@ func init() {
 }
 
 // MockDNSProvider is a mock DNS provider, for testing config with DNS modules.
-type MockDNSProvider struct{}
+type MockDNSProvider struct {
+	Argument string `json:"argument,omitempty"` // optional argument useful for testing
+}
 
 // CaddyModule returns the Caddy module information.
 func (MockDNSProvider) CaddyModule() caddy.ModuleInfo {
@@ -31,7 +33,15 @@ func (MockDNSProvider) Provision(ctx caddy.Context) error {
 }
 
 // UnmarshalCaddyfile sets up the module from Caddyfile tokens.
-func (MockDNSProvider) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
+func (p *MockDNSProvider) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {
+	d.Next() // consume directive name
+
+	if d.NextArg() {
+		p.Argument = d.Val()
+	}
+	if d.NextArg() {
+		return d.Errf("unexpected argument '%s'", d.Val())
+	}
 	return nil
 }