update

internal/app/authorization.go

@@ -874,3 +874,12 @@ func (s *Server) audit(
 }
 
 var errAuthorizationDenied = errors.New("authorization denied")
+
+var (
+	errCodeNotFound         = fmt.Errorf("%w: code not found", errAuthorizationDenied)
+	errCodeExpired          = fmt.Errorf("%w: code expired", errAuthorizationDenied)
+	errCodeRevoked          = fmt.Errorf("%w: code revoked", errAuthorizationDenied)
+	errActionNotAuthorized  = fmt.Errorf("%w: action not authorized", errAuthorizationDenied)
+	errPackageNotAuthorized = fmt.Errorf("%w: package not authorized", errAuthorizationDenied)
+	errHostLimitReached     = fmt.Errorf("%w: host limit reached", errAuthorizationDenied)
+)

internal/app/download.go

@@ -77,8 +77,12 @@ func (s *Server) handleExchange(w http.ResponseWriter, r *http.Request) {
 			status = http.StatusForbidden
 			message = "authorization is invalid, expired, revoked, or at its host limit"
 		}
-		_ = s.audit(r.Context(), "code_exchange_failed", "", nil,
-			request.Hostname, "", sourceIP, err.Error())
+		var failedAuthorizationID *uint64
+		if authorizationID != 0 {
+			failedAuthorizationID = &authorizationID
+		}
+		_ = s.audit(r.Context(), "code_exchange_failed", "", failedAuthorizationID,
+			request.Hostname, "", sourceIP, codeExchangeFailureDetails(request.Code, err))
 		writeJSON(w, status, map[string]string{"error": message})
 		return
 	}
@@ -110,6 +114,55 @@ func (s *Server) exchangeRateLimited(r *http.Request, sourceIP string) (bool, er
 	return attempts >= 10, err
 }
 
+func codeExchangeFailureDetails(code string, err error) string {
+	reason := "internal_error"
+	switch {
+	case errors.Is(err, errCodeNotFound):
+		reason = "code_not_found"
+	case errors.Is(err, errCodeExpired):
+		reason = "code_expired"
+	case errors.Is(err, errCodeRevoked):
+		reason = "code_revoked"
+	case errors.Is(err, errActionNotAuthorized):
+		reason = "action_not_authorized"
+	case errors.Is(err, errPackageNotAuthorized):
+		reason = "package_not_authorized"
+	case errors.Is(err, errHostLimitReached):
+		reason = "host_limit_reached"
+	case errors.Is(err, errAuthorizationDenied):
+		reason = "authorization_denied"
+	}
+
+	format := "unexpected"
+	if validDeploymentCodeFormat(code) {
+		format = "expected"
+	}
+	hint := "unavailable"
+	if strings.HasPrefix(code, "TAPM-") && len(code) >= 5 {
+		hint = code[len(code)-5:]
+	}
+	return fmt.Sprintf(
+		"reason=%s code_hint=%s normalized_length=%d format=%s",
+		reason, hint, len(code), format,
+	)
+}
+
+func validDeploymentCodeFormat(code string) bool {
+	if len(code) != 16 || !strings.HasPrefix(code, "TAPM-") || code[10] != '-' {
+		return false
+	}
+	const allowed = "0123456789ABCDEFGHJKMNPQRSTVWXYZ"
+	for index, character := range code {
+		if index < 5 || index == 10 {
+			continue
+		}
+		if !strings.ContainsRune(allowed, character) {
+			return false
+		}
+	}
+	return true
+}
+
 func (s *Server) exchangeDeploymentCode(
 	r *http.Request,
 	request exchangeRequest,
@@ -127,21 +180,31 @@ func (s *Server) exchangeDeploymentCode(
 	var authorizationID uint64
 	var hostLimit int
 	var expiresAt time.Time
+	var authorizationStatus string
 	err = tx.QueryRowContext(
 		r.Context(),
-		`SELECT id, host_limit, expires_at
+		`SELECT id, host_limit, expires_at,
+		        CASE
+		          WHEN revoked_at IS NOT NULL THEN 'revoked'
+		          WHEN expires_at <= CURRENT_TIMESTAMP THEN 'expired'
+		          ELSE 'active'
+		        END
 		   FROM authorizations
-		  WHERE code_hash = ?
-		    AND revoked_at IS NULL
-		    AND expires_at > CURRENT_TIMESTAMP`,
+		  WHERE code_hash = ?`,
 		codeHash[:],
-	).Scan(&authorizationID, &hostLimit, &expiresAt)
+	).Scan(&authorizationID, &hostLimit, &expiresAt, &authorizationStatus)
 	if errors.Is(err, sql.ErrNoRows) {
-		return response, 0, errAuthorizationDenied
+		return response, 0, errCodeNotFound
 	}
 	if err != nil {
 		return response, 0, err
 	}
+	switch authorizationStatus {
+	case "revoked":
+		return response, authorizationID, errCodeRevoked
+	case "expired":
+		return response, authorizationID, errCodeExpired
+	}
 
 	if request.RequestedAction != "" {
 		var authorized int
@@ -158,7 +221,7 @@ func (s *Server) exchangeDeploymentCode(
 			return response, 0, err
 		}
 		if authorized != 1 {
-			return response, 0, errAuthorizationDenied
+			return response, authorizationID, errActionNotAuthorized
 		}
 	}
 	if request.RequestedPackage != "" {
@@ -176,7 +239,7 @@ func (s *Server) exchangeDeploymentCode(
 			return response, 0, err
 		}
 		if authorized != 1 {
-			return response, 0, errAuthorizationDenied
+			return response, authorizationID, errPackageNotAuthorized
 		}
 	}
 
@@ -197,7 +260,7 @@ func (s *Server) exchangeDeploymentCode(
 			return response, 0, err
 		}
 		if hostCount >= hostLimit {
-			return response, 0, errAuthorizationDenied
+			return response, authorizationID, errHostLimitReached
 		}
 		result, err := tx.ExecContext(
 			r.Context(),

internal/app/download_test.go

@@ -0,0 +1,109 @@
+package app
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestCodeExchangeFailureDetailsRetainsOnlySafeDiagnostics(t *testing.T) {
+	t.Parallel()
+	code := "TAPM-12345-ABCDE"
+	details := codeExchangeFailureDetails(code, errCodeNotFound)
+
+	for _, expected := range []string{
+		"reason=code_not_found",
+		"code_hint=ABCDE",
+		"normalized_length=16",
+		"format=expected",
+	} {
+		if !strings.Contains(details, expected) {
+			t.Errorf("details %q do not contain %q", details, expected)
+		}
+	}
+	if strings.Contains(details, code) || strings.Contains(details, "12345") {
+		t.Fatalf("details contain more of the submitted code than its hint: %q", details)
+	}
+}
+
+func TestCodeExchangeFailureDetailsDoesNotHintUnrelatedInput(t *testing.T) {
+	t.Parallel()
+	details := codeExchangeFailureDetails("not-a-deployment-secret", errCodeNotFound)
+	if !strings.Contains(details, "code_hint=unavailable") ||
+		!strings.Contains(details, "format=unexpected") {
+		t.Fatalf("unexpected details for malformed input: %q", details)
+	}
+	if strings.Contains(details, "ecret") {
+		t.Fatalf("details retained part of unrelated input: %q", details)
+	}
+}
+
+func TestCodeExchangeFailureReasons(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		err    error
+		reason string
+	}{
+		{errCodeExpired, "code_expired"},
+		{errCodeRevoked, "code_revoked"},
+		{errActionNotAuthorized, "action_not_authorized"},
+		{errPackageNotAuthorized, "package_not_authorized"},
+		{errHostLimitReached, "host_limit_reached"},
+	}
+	for _, test := range tests {
+		if details := codeExchangeFailureDetails("TAPM-12345-ABCDE", test.err); !strings.Contains(details, "reason="+test.reason) {
+			t.Errorf("details %q do not contain reason %q", details, test.reason)
+		}
+	}
+}
+
+func TestFailedExpiredCodeAttemptIsLinkedToDeployment(t *testing.T) {
+	server, _ := newAuthorizationTestServer(t)
+	code := "TAPM-12345-ABCDE"
+	codeHash := hashValue(code)
+	if _, err := server.db.Exec(
+		`INSERT INTO authorizations
+			(id, code_hash, code_hint, created_by, customer_label, host_limit, expires_at)
+		 VALUES (42, ?, 'ABCDE', 'taiadmin', 'Acme migration', 3, ?)`,
+		codeHash[:], time.Now().UTC().Add(-time.Hour),
+	); err != nil {
+		t.Fatal(err)
+	}
+
+	body, err := json.Marshal(exchangeRequest{
+		Code:            code,
+		HostFingerprint: "0123456789abcdef",
+		Hostname:        "pve01",
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	request := httptest.NewRequest(http.MethodPost, "/api/v1/exchange", bytes.NewReader(body))
+	response := httptest.NewRecorder()
+	server.handleExchange(response, request)
+	if response.Code != http.StatusForbidden {
+		t.Fatalf("status = %d, want %d", response.Code, http.StatusForbidden)
+	}
+
+	var authorizationID uint64
+	var hostname, details string
+	if err := server.db.QueryRow(
+		`SELECT authorization_id, hostname, details
+		   FROM audit_events
+		  WHERE event_type = 'code_exchange_failed'`,
+	).Scan(&authorizationID, &hostname, &details); err != nil {
+		t.Fatal(err)
+	}
+	if authorizationID != 42 || hostname != "pve01" {
+		t.Fatalf("audit event authorization/hostname = %d/%q", authorizationID, hostname)
+	}
+	if !strings.Contains(details, "reason=code_expired") ||
+		!strings.Contains(details, "code_hint=ABCDE") ||
+		strings.Contains(details, code) {
+		t.Fatalf("unsafe or incomplete audit details: %q", details)
+	}
+}

internal/app/server_test.go

@@ -79,9 +79,14 @@ func TestPackageAndAuditTemplatesExecute(t *testing.T) {
 		SourceIP:      "203.0.113.10",
 		CreatedAt:     time.Now(),
 	}}
-	if err := templates.ExecuteTemplate(io.Discard, "audit.html", data); err != nil {
+	var auditOutput bytes.Buffer
+	if err := templates.ExecuteTemplate(&auditOutput, "audit.html", data); err != nil {
 		t.Fatal(err)
 	}
+	if !strings.Contains(auditOutput.String(), "Failed code attempts") ||
+		!strings.Contains(auditOutput.String(), "audit_event=code_exchange_failed") {
+		t.Fatal("audit page does not include the failed-code-attempt shortcut")
+	}
 }
 
 func TestFleetTemplateExecutes(t *testing.T) {

internal/app/static/app.css

@@ -247,6 +247,7 @@ dd { margin: 4px 0 0; overflow-wrap: anywhere; }
 .package-row { display: flex; justify-content: space-between; gap: 16px; padding: 14px 0; border-bottom: 1px solid var(--line); }
 .package-row div { display: grid; gap: 4px; }
 .package-row small { color: var(--muted); }
+.package-row .status { align-items: center; justify-content: center; align-self: center; line-height: 1; text-align: center; }
 .toggle { display: flex; align-items: center; gap: 9px; }
 .empty, .fine-print { color: var(--muted); }
 .package-forms { display: grid; gap: 26px; }

internal/app/templates/audit.html

@@ -46,9 +46,10 @@
         <label>Details contain <input name="audit_details" value="{{.AuditFilters.Details}}" placeholder="customer or action"></label>
         <div class="audit-filter-actions">
           <button class="button secondary" type="submit">Apply filters</button>
+          <a class="text-button" href="/portal/audit?audit_range=30d&amp;audit_event=code_exchange_failed">Failed code attempts</a>
           <a class="text-button" href="/portal/audit?audit_range=30d">Clear filters</a>
         </div>
-        <p class="form-help audit-filter-note">Audit records are retained indefinitely. Up to the newest 250 matching events are shown.</p>
+        <p class="form-help audit-filter-note">Failed code attempts show a reason, hostname, source IP, code length, and only the five-character code hint. Full submitted codes are never retained. Up to the newest 250 matching events are shown.</p>
       </form>
       {{template "audit-rows" .}}
     </section>