add initial Go implementation of arcline-audit

Implements the full site health auditor with four check groups:

  - SSL/TLS (certificate validity, expiry, chain, TLS version, ciphers)

  - HTTP (redirect chain, security headers, response time)

  - DNS (A/AAAA, MX, SPF, DKIM, DMARC, DNSSEC)

  - Infrastructure (CDN detection, common port probes)

Includes CLI with --checks filter, --json and --out flags,

cross-compile Makefile, and GitLab CI pipeline.

Signed-off-by: Blake Ridgway <blake@blakeridgway.com>

internal/types/types.go

@@ -0,0 +1,111 @@
+package types
+
+import "time"
+
+// Status represents the result status of a single check.
+type Status string
+
+const (
+	StatusOK   Status = "OK"
+	StatusWarn Status = "WARN"
+	StatusFail Status = "FAIL"
+	StatusInfo Status = "INFO"
+)
+
+// CheckResult represents the outcome of a single audit check.
+type CheckResult struct {
+	Status  Status `json:"status"`
+	Message string `json:"message"`
+}
+
+// SSLResult holds all SSL/TLS check results.
+type SSLResult struct {
+	Checks    []CheckResult `json:"checks"`
+	Issuer    string        `json:"issuer,omitempty"`
+	Expiry    time.Time     `json:"expiry,omitempty"`
+	DaysLeft  int           `json:"days_left,omitempty"`
+	TLSVersion string       `json:"tls_version,omitempty"`
+}
+
+// HTTPResult holds all HTTP check results.
+type HTTPResult struct {
+	Checks        []CheckResult `json:"checks"`
+	ResponseTime  time.Duration `json:"response_time_ms"`
+	FinalURL      string        `json:"final_url,omitempty"`
+	RedirectHops  int           `json:"redirect_hops,omitempty"`
+}
+
+// DNSResult holds all DNS check results.
+type DNSResult struct {
+	Checks []CheckResult `json:"checks"`
+}
+
+// InfraResult holds all infrastructure check results.
+type InfraResult struct {
+	Checks []CheckResult `json:"checks"`
+	ASN    string        `json:"asn,omitempty"`
+	Org    string        `json:"org,omitempty"`
+	CDN    string        `json:"cdn,omitempty"`
+}
+
+// AuditResult is the top-level result containing all check sections.
+type AuditResult struct {
+	Domain string      `json:"domain"`
+	Time   time.Time   `json:"time"`
+	SSL    SSLResult   `json:"ssl"`
+	HTTP   HTTPResult  `json:"http"`
+	DNS    DNSResult   `json:"dns"`
+	Infra  InfraResult `json:"infra"`
+}
+
+// CheckSet is a bitmask of check categories for filtering.
+type CheckSet int
+
+const (
+	CheckSSL  CheckSet = 1 << iota
+	CheckHTTP
+	CheckDNS
+	CheckInfra
+	CheckAll = CheckSSL | CheckHTTP | CheckDNS | CheckInfra
+)
+
+// ParseChecks parses a comma-separated list of check names into a CheckSet.
+func ParseChecks(s string) CheckSet {
+	if s == "" || s == "all" {
+		return CheckAll
+	}
+	var cs CheckSet
+	m := map[string]CheckSet{
+		"ssl":   CheckSSL,
+		"http":  CheckHTTP,
+		"dns":   CheckDNS,
+		"infra": CheckInfra,
+	}
+	for _, name := range splitCSV(s) {
+		if v, ok := m[name]; ok {
+			cs |= v
+		}
+	}
+	if cs == 0 {
+		return CheckAll
+	}
+	return cs
+}
+
+func splitCSV(s string) []string {
+	var parts []string
+	start := 0
+	for i := 0; i < len(s); i++ {
+		if s[i] == ',' {
+			if i > start {
+				parts = append(parts, s[start:i])
+			}
+			start = i + 1
+		}
+	}
+	if start < len(s) {
+		parts = append(parts, s[start:])
+	}
+	return parts
+}
+