Initial commit

2026-04-23 19:37:14 +07:00 · 2026-04-23 19:37:14 +07:00 · eea7e4e459
commit eea7e4e459
22 changed files with 2520 additions and 0 deletions
--- a/checker/definition.go
+++ b/checker/definition.go
@ -0,0 +1,117 @@
+package checker
+
+import (
+	"fmt"
+	"time"
+
+	sdk "git.happydns.org/checker-sdk-go/checker"
+)
+
+// Version is overridden at build time via -ldflags by main.go and plugin.go.
+var Version = "built-in"
+
+func Definition() *sdk.CheckerDefinition {
+	def := &sdk.CheckerDefinition{
+		ID:      "alias",
+		Name:    "CNAME / DNAME / ALIAS chain",
+		Version: Version,
+		Availability: sdk.CheckerAvailability{
+			ApplyToService: true,
+			ApplyToDomain:  true,
+			ApplyToZone:    true,
+			LimitToServices: []string{
+				"svcs.CNAME",
+				"svcs.SpecialCNAME",
+			},
+		},
+		ObservationKeys: []sdk.ObservationKey{ObservationKeyAlias},
+		Options: sdk.CheckerOptionsDocumentation{
+			UserOpts: []sdk.CheckerOptionDocumentation{
+				{
+					Id:          "allowApexCNAME",
+					Type:        "bool",
+					Label:       "Allow CNAME at apex",
+					Description: "Shared by cname_at_apex and cname_coexistence: when enabled, a CNAME at a zone apex (and its coexistence violations) are downgraded to warnings. RFC 1912 forbids this, so leaving it off is strongly recommended.",
+					Default:     defaultAllowApexCNAME,
+				},
+				{
+					Id:          "recognizeApexFlattening",
+					Type:        "bool",
+					Label:       "Recognize ALIAS/ANAME flattening",
+					Description: "Shared by apex_flattening and cname_coexistence: when enabled, providers that serve A/AAAA at the apex (ALIAS/ANAME pseudo-records) are recognised as intentional and excused from coexistence violations.",
+					Default:     defaultRecognizeApexFlattening,
+				},
+			},
+			DomainOpts: []sdk.CheckerOptionDocumentation{
+				{
+					Id:       "domain_name",
+					Label:    "Parent domain name",
+					AutoFill: sdk.AutoFillDomainName,
+				},
+				{
+					Id:       "subdomain",
+					Label:    "Subdomain",
+					AutoFill: sdk.AutoFillSubdomain,
+				},
+			},
+			ServiceOpts: []sdk.CheckerOptionDocumentation{
+				{
+					Id:       "service_type",
+					Label:    "Service type",
+					AutoFill: sdk.AutoFillServiceType,
+				},
+				{
+					Id:       "service",
+					Label:    "Service",
+					AutoFill: sdk.AutoFillService,
+				},
+			},
+		},
+		Rules: []sdk.CheckRule{
+			apexLookupRule{},
+			chainLoopRule{},
+			chainLengthRule{},
+			chainQueryErrorRule{},
+			chainRcodeRule{},
+			hopTTLRule{},
+			cnameAtApexRule{},
+			apexFlatteningRule{},
+			cnameCoexistenceRule{},
+			cnameDnssecRule{},
+			targetResolvableRule{},
+			multipleRecordsRule{},
+		},
+		HasHTMLReport: true,
+		Interval: &sdk.CheckIntervalSpec{
+			Min:     5 * time.Minute,
+			Max:     24 * time.Hour,
+			Default: 1 * time.Hour,
+		},
+	}
+	def.BuildRulesInfo()
+	return def
+}
+
+// ValidateOptions runs on the host before Collect so bad options are rejected
+// up-front rather than producing an unhelpful runtime error mid-walk.
+func (p *aliasProvider) ValidateOptions(opts sdk.CheckerOptions) error {
+	if v, ok := opts["maxChainLength"]; ok {
+		f, ok := v.(float64)
+		if !ok {
+			return fmt.Errorf("maxChainLength must be a number")
+		}
+		if f < 1 {
+			return fmt.Errorf("maxChainLength must be >= 1")
+		}
+	}
+	if v, ok := opts["minTargetTTL"]; ok {
+		f, ok := v.(float64)
+		if !ok {
+			return fmt.Errorf("minTargetTTL must be a number")
+		}
+		if f < 0 {
+			return fmt.Errorf("minTargetTTL must be >= 0")
+		}
+	}
+	return nil
+}