feat(07-01): add JWT mint, refresh, and blacklist primitives

Co-authored-by: Cursor <cursoragent@cursor.com>

bouncer/blacklist.go

@@ -0,0 +1,126 @@
+package bouncer
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"regexp"
+	"sync"
+	"time"
+)
+
+// BlacklistStore records revoked jti values. IsBlacklisted is true only once
+// validUntil has been reached, so a grace window can keep a just-rotated
+// token usable. Sweep drops rows whose storage expiry has passed.
+type BlacklistStore interface {
+	Add(ctx context.Context, jti string, expiresAt, validUntil time.Time) error
+	IsBlacklisted(ctx context.Context, jti string) (bool, error)
+	Sweep(ctx context.Context, now time.Time) error
+}
+
+type blEntry struct {
+	expiresAt  time.Time
+	validUntil time.Time
+}
+
+// MemoryBlacklist is an in-process store for tests. Expired rows are dropped
+// on read, matching surf.MemoryStore.
+type MemoryBlacklist struct {
+	mu      sync.Mutex
+	entries map[string]blEntry
+}
+
+// NewMemoryBlacklist returns an empty in-process blacklist.
+func NewMemoryBlacklist() *MemoryBlacklist {
+	return &MemoryBlacklist{entries: make(map[string]blEntry)}
+}
+
+func (m *MemoryBlacklist) Add(_ context.Context, jti string, expiresAt, validUntil time.Time) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.entries[jti] = blEntry{expiresAt: expiresAt, validUntil: validUntil}
+	return nil
+}
+
+func (m *MemoryBlacklist) IsBlacklisted(_ context.Context, jti string) (bool, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	e, ok := m.entries[jti]
+	if !ok {
+		return false, nil
+	}
+	now := time.Now()
+	if now.After(e.expiresAt) {
+		delete(m.entries, jti)
+		return false, nil
+	}
+	return !now.Before(e.validUntil), nil
+}
+
+func (m *MemoryBlacklist) Sweep(_ context.Context, now time.Time) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	for k, e := range m.entries {
+		if e.expiresAt.Before(now) {
+			delete(m.entries, k)
+		}
+	}
+	return nil
+}
+
+var blacklistIdent = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_]*$`)
+
+// PostgresBlacklist stores revoked jti rows in a caller-supplied table.
+// The table name is a plugin constant, still checked so it cannot be interpolated raw.
+type PostgresBlacklist struct {
+	db    *sql.DB
+	table string
+}
+
+// NewPostgresBlacklist binds db to table. table must be a plain SQL identifier.
+func NewPostgresBlacklist(db *sql.DB, table string) *PostgresBlacklist {
+	return &PostgresBlacklist{db: db, table: table}
+}
+
+func (p *PostgresBlacklist) checkTable() error {
+	if p == nil || !blacklistIdent.MatchString(p.table) {
+		return fmt.Errorf("bouncer: blacklist table %q is not a safe identifier", p.table)
+	}
+	return nil
+}
+
+func (p *PostgresBlacklist) Add(ctx context.Context, jti string, expiresAt, validUntil time.Time) error {
+	if err := p.checkTable(); err != nil {
+		return err
+	}
+	q := fmt.Sprintf(`INSERT INTO %s (jti, expires_at, valid_until) VALUES ($1, $2, $3)
+ON CONFLICT (jti) DO UPDATE SET expires_at = EXCLUDED.expires_at, valid_until = EXCLUDED.valid_until`, p.table)
+	_, err := p.db.ExecContext(ctx, q, jti, expiresAt, validUntil)
+	return err
+}
+
+func (p *PostgresBlacklist) IsBlacklisted(ctx context.Context, jti string) (bool, error) {
+	if err := p.checkTable(); err != nil {
+		return false, err
+	}
+	q := fmt.Sprintf(`SELECT valid_until FROM %s WHERE jti = $1`, p.table)
+	var validUntil time.Time
+	err := p.db.QueryRowContext(ctx, q, jti).Scan(&validUntil)
+	if errors.Is(err, sql.ErrNoRows) {
+		return false, nil
+	}
+	if err != nil {
+		return false, err
+	}
+	return !time.Now().Before(validUntil), nil
+}
+
+func (p *PostgresBlacklist) Sweep(ctx context.Context, now time.Time) error {
+	if err := p.checkTable(); err != nil {
+		return err
+	}
+	q := fmt.Sprintf(`DELETE FROM %s WHERE expires_at < $1`, p.table)
+	_, err := p.db.ExecContext(ctx, q, now)
+	return err
+}

bouncer/context.go

@@ -1,13 +1,19 @@
 package bouncer
 
-import "context"
+import (
+	"context"
+	"time"
+)
 
 type userKey struct{}
 
 // Principal is the authenticated identity stored on the request context.
+// PreferredLocale empty means no override. TokensValidAfter zero means no cutoff.
 type Principal struct {
 	ID                 uint
 	MustChangePassword bool
+	PreferredLocale    string
+	TokensValidAfter   time.Time
 }
 
 // WithUser stores the verified principal on ctx.

bouncer/jwt.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/golang-jwt/jwt/v5"
 )
@@ -65,8 +66,10 @@ func Middleware(secret string, users UserProvider) func(http.Handler) http.Handl
 }
 
 type jwtGuard struct {
-	secret string
-	users  UserProvider
+	secret      string
+	users       UserProvider
+	bl          BlacklistStore
+	cookieNames []string
 }
 
 var (
@@ -74,19 +77,19 @@ var (
 	_ UnauthorizedWriter = (*jwtGuard)(nil)
 )
 
-// NewJWTGuard adapts the existing bearerToken -> Verify -> users.FindByID
-// chain (identical to Middleware's body) into a Guard + UnauthorizedWriter,
-// so Registry.Middleware("jwt") is byte-identical to bouncer.Middleware.
-func NewJWTGuard(secret string, users UserProvider) Guard {
-	return &jwtGuard{secret: secret, users: users}
+// NewJWTGuard adapts bearer/cookie extraction, VerifyClaims, and users.FindByID
+// into a Guard + UnauthorizedWriter. bl may be nil. An empty cookieNames list
+// is Bearer-only; otherwise each name is tried, in order, after the Authorization header.
+func NewJWTGuard(secret string, users UserProvider, bl BlacklistStore, cookieNames ...string) Guard {
+	return &jwtGuard{secret: secret, users: users, bl: bl, cookieNames: cookieNames}
 }
 
 func (g *jwtGuard) Authenticate(r *http.Request) (*Principal, error) {
-	raw, err := bearerToken(r)
+	raw, err := extractToken(r, g.cookieNames)
 	if err != nil {
 		return nil, err
 	}
-	sub, err := Verify(raw, g.secret)
+	sub, iat, _, jti, err := VerifyClaims(raw, g.secret)
 	if err != nil {
 		return nil, err
 	}
@@ -104,6 +107,18 @@ func (g *jwtGuard) Authenticate(r *http.Request) (*Principal, error) {
 	if user == nil {
 		return nil, errors.New(msgUserNotFound)
 	}
+	if g.bl != nil {
+		blocked, err := g.bl.IsBlacklisted(r.Context(), jti)
+		if err != nil {
+			return nil, errors.New("Authentication error")
+		}
+		if blocked {
+			return nil, errors.New(msgBadSignature)
+		}
+	}
+	if !user.TokensValidAfter.IsZero() && iat.Before(user.TokensValidAfter) {
+		return nil, errors.New(msgUserNotFound)
+	}
 	return user, nil
 }
 
@@ -131,6 +146,70 @@ func Verify(tokenString, secret string) (string, error) {
 	return sub, nil
 }
 
+// VerifyClaims parses a token the same way Verify does and also returns iat, exp, and jti.
+func VerifyClaims(tokenString, secret string) (sub string, iat, exp time.Time, jti string, err error) {
+	if strings.TrimSpace(secret) == "" {
+		return "", time.Time{}, time.Time{}, "", fmt.Errorf("bouncer: jwt secret is empty")
+	}
+	parser := jwt.NewParser(jwt.WithValidMethods([]string{"HS256"}), jwt.WithExpirationRequired())
+	claims := jwt.MapClaims{}
+	_, err = parser.ParseWithClaims(tokenString, claims, func(t *jwt.Token) (any, error) {
+		return []byte(secret), nil
+	})
+	if err != nil {
+		return "", time.Time{}, time.Time{}, "", mapJWTError(err)
+	}
+	sub = subject(claims)
+	if sub == "" {
+		return "", time.Time{}, time.Time{}, "", errors.New(msgRequiredClaims)
+	}
+	iat, _ = claimTime(claims, "iat")
+	exp, _ = claimTime(claims, "exp")
+	jti, _ = claims["jti"].(string)
+	return sub, iat, exp, jti, nil
+}
+
+func extractToken(r *http.Request, cookieNames []string) (string, error) {
+	raw, err := bearerToken(r)
+	if err == nil {
+		return raw, nil
+	}
+	if len(cookieNames) == 0 {
+		return "", err
+	}
+	for _, name := range cookieNames {
+		c, cerr := r.Cookie(name)
+		if cerr != nil {
+			continue
+		}
+		v := strings.TrimSpace(c.Value)
+		if v != "" {
+			return v, nil
+		}
+	}
+	return "", errors.New(msgTokenNotProvided)
+}
+
+func claimTime(claims jwt.MapClaims, key string) (time.Time, bool) {
+	switch v := claims[key].(type) {
+	case float64:
+		if math.IsNaN(v) || math.IsInf(v, 0) {
+			return time.Time{}, false
+		}
+		return time.Unix(int64(v), 0), true
+	case json.Number:
+		n, err := v.Int64()
+		if err != nil {
+			return time.Time{}, false
+		}
+		return time.Unix(n, 0), true
+	case int64:
+		return time.Unix(v, 0), true
+	default:
+		return time.Time{}, false
+	}
+}
+
 func bearerToken(r *http.Request) (string, error) {
 	h := strings.TrimSpace(r.Header.Get("Authorization"))
 	if h == "" {

bouncer/mint.go

@@ -0,0 +1,57 @@
+package bouncer
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+// prvHash is sha1("Golem15\User\Models\User"), the lock-subject PHP jwt-auth
+// stamps on every user token.
+const prvHash = "a867434cbc213adfbe78a02bed7082a6bd99c883"
+
+type registeredClaims struct {
+	jwt.RegisteredClaims
+	Prv string `json:"prv,omitempty"`
+}
+
+// Mint signs an HS256 token whose iss is the full URL of the minting endpoint.
+// The returned jti is the token's own jti claim.
+func Mint(secret, sub, issuerURL string, ttl time.Duration) (string, string, error) {
+	if strings.TrimSpace(secret) == "" {
+		return "", "", fmt.Errorf("bouncer: jwt secret is empty")
+	}
+	jti, err := newJTI()
+	if err != nil {
+		return "", "", err
+	}
+	now := time.Now()
+	claims := registeredClaims{
+		RegisteredClaims: jwt.RegisteredClaims{
+			Issuer:    issuerURL,
+			Subject:   sub,
+			ExpiresAt: jwt.NewNumericDate(now.Add(ttl)),
+			NotBefore: jwt.NewNumericDate(now),
+			IssuedAt:  jwt.NewNumericDate(now),
+			ID:        jti,
+		},
+		Prv: prvHash,
+	}
+	signed, err := jwt.NewWithClaims(jwt.SigningMethodHS256, claims).SignedString([]byte(secret))
+	if err != nil {
+		return "", "", err
+	}
+	return signed, jti, nil
+}
+
+func newJTI() (string, error) {
+	buf := make([]byte, 16)
+	if _, err := rand.Read(buf); err != nil {
+		return "", err
+	}
+	return hex.EncodeToString(buf), nil
+}

bouncer/refresh.go

@@ -0,0 +1,69 @@
+package bouncer
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"time"
+
+	"github.com/golang-jwt/jwt/v5"
+)
+
+// Refresh issues a new token for a still-refreshable subject. exp is not
+// required to be in the future; iat must fall inside refreshTTL. The previous
+// jti is blacklisted with validUntil = now+grace. Storage expiry follows PHP
+// jwt-auth: the later of the old exp and iat+refreshTTL, plus one minute, so
+// a logged-out token cannot be refreshed again for the rest of its refresh window.
+func Refresh(secret, tokenString string, refreshTTL time.Duration, bl BlacklistStore, grace time.Duration, issuerURL string) (string, error) {
+	if strings.TrimSpace(secret) == "" {
+		return "", errors.New("bouncer: jwt secret is empty")
+	}
+	parser := jwt.NewParser(jwt.WithValidMethods([]string{"HS256"}), jwt.WithoutClaimsValidation())
+	claims := jwt.MapClaims{}
+	if _, err := parser.ParseWithClaims(tokenString, claims, func(*jwt.Token) (any, error) {
+		return []byte(secret), nil
+	}); err != nil {
+		return "", mapJWTError(err)
+	}
+	sub := subject(claims)
+	if sub == "" {
+		return "", errors.New(msgRequiredClaims)
+	}
+	iat, ok := claimTime(claims, "iat")
+	if !ok || time.Now().After(iat.Add(refreshTTL)) {
+		return "", errors.New("Token has expired and can no longer be refreshed")
+	}
+	jti, _ := claims["jti"].(string)
+	if bl != nil && jti != "" {
+		blocked, err := bl.IsBlacklisted(context.Background(), jti)
+		if err != nil {
+			return "", err
+		}
+		if blocked {
+			return "", errors.New("The token has been blacklisted")
+		}
+	}
+	exp, expOK := claimTime(claims, "exp")
+	ttl := exp.Sub(iat)
+	if !expOK || ttl <= 0 {
+		return "", errors.New(msgRequiredClaims)
+	}
+	next, _, err := Mint(secret, sub, issuerURL, ttl)
+	if err != nil {
+		return "", err
+	}
+	if bl != nil && jti != "" {
+		// PHP Blacklist::getMinutesUntilExpired keeps the row until the later of
+		// exp and iat+refreshTTL, plus one minute. Using exp alone would drop a
+		// logged-out token whose access exp has passed but whose refresh window
+		// has not, and the next Refresh would succeed.
+		expiresAt := iat.Add(refreshTTL).Add(time.Minute)
+		if until := exp.Add(time.Minute); until.After(expiresAt) {
+			expiresAt = until
+		}
+		if err := bl.Add(context.Background(), jti, expiresAt, time.Now().Add(grace)); err != nil {
+			return "", err
+		}
+	}
+	return next, nil
+}

bouncer/registry_test.go

@@ -172,7 +172,7 @@ func TestJWTGuardRegistryMatchesMiddleware(t *testing.T) {
 		w.WriteHeader(http.StatusNoContent)
 	}))
 	reg := NewRegistry()
-	if err := reg.Register("golem15.user", "jwt", NewJWTGuard(secret, users)); err != nil {
+	if err := reg.Register("golem15.user", "jwt", NewJWTGuard(secret, users, nil)); err != nil {
 		t.Fatal(err)
 	}
 	viaReg, err := reg.Middleware("jwt")