fix: tolerate retried internal api nonce

server/internal_api.go

@@ -185,7 +185,8 @@ func authorizeInternalAPI(wrt http.ResponseWriter, req *http.Request, capability
 		writeIMError(wrt, req, http.StatusUnauthorized, 30043, imReasonAuthRequired, "invalid internal signature", nil)
 		return false
 	}
-	if !claimInternalNonce(serviceName, nonce, time.Now().Add(window)) {
+	requestClaim := internalRequestClaimValue(signingText)
+	if !claimInternalNonce(serviceName, nonce, requestClaim, time.Now().Add(window)) {
 		writeIMError(wrt, req, http.StatusUnauthorized, 30043, imReasonAuthRequired, "internal nonce replayed", nil)
 		return false
 	}
@@ -572,23 +573,36 @@ func verifyInternalSignature(secret, signingText, signature string) bool {
 	return false
 }
 
-func claimInternalNonce(serviceName, nonce string, expiresAt time.Time) bool {
+func claimInternalNonce(serviceName, nonce, requestClaim string, expiresAt time.Time) bool {
 	ttl := time.Until(expiresAt)
-	if ok, enabled, err := store.ClaimShortState("internal_api_nonce", fmt.Sprintf("%s:%s", serviceName, nonce), ttl); enabled {
+	nonceKey := fmt.Sprintf("%s:%s", serviceName, nonce)
+	if claimed, sameValue, enabled, err := store.ClaimShortStateValue("internal_api_nonce", nonceKey, requestClaim, ttl); enabled {
 		if err != nil {
 			logs.Warn.Println("internal api: failed to claim nonce in redis", err)
 			return false
 		}
-		return ok
+		return claimed || sameValue
 	}
 	now := time.Now()
 	internalAPI.nonces.Range(func(key, value any) bool {
-		if expires, ok := value.(time.Time); ok && expires.Before(now) {
+		if claim, ok := value.(internalNonceClaim); ok && claim.expiresAt.Before(now) {
 			internalAPI.nonces.Delete(key)
 		}
 		return true
 	})
-	nonceKey := fmt.Sprintf("%s:%s", serviceName, nonce)
+	if existing, loaded := internalAPI.nonces.LoadOrStore(nonceKey, internalNonceClaim{value: requestClaim, expiresAt: expiresAt}); loaded {
-	_, loaded := internalAPI.nonces.LoadOrStore(nonceKey, expiresAt)
+		claim, ok := existing.(internalNonceClaim)
-	return !loaded
+		return ok && claim.value == requestClaim
+	}
+	return true
+}
+
+type internalNonceClaim struct {
+	value     string
+	expiresAt time.Time
+}
+
+func internalRequestClaimValue(signingText string) string {
+	sum := sha256.Sum256([]byte(signingText))
+	return hex.EncodeToString(sum[:])
 }

server/store/group_message_runtime.go

@@ -70,6 +70,7 @@ type groupMessageRuntime interface {
 	CachedSetContains(tenantID types.TenantID, namespace, id, member string) (bool, error)
 	AllowRate(tenantID types.TenantID, scope string, limit int, window time.Duration) (bool, int, time.Duration, error)
 	ClaimShortState(namespace, id string, ttl time.Duration) (bool, error)
+	ClaimShortStateValue(namespace, id, value string, ttl time.Duration) (bool, bool, error)
 }
 
 var groupMsgRuntime groupMessageRuntime
@@ -97,6 +98,14 @@ func ClaimShortState(namespace, id string, ttl time.Duration) (bool, bool, error
 	return ok, true, err
 }
 
+func ClaimShortStateValue(namespace, id, value string, ttl time.Duration) (bool, bool, bool, error) {
+	if groupMsgRuntime == nil || namespace == "" || id == "" || value == "" {
+		return false, false, false, nil
+	}
+	claimed, sameValue, err := groupMsgRuntime.ClaimShortStateValue(namespace, id, value, ttl)
+	return claimed, sameValue, true, err
+}
+
 func RefreshUserPresence(tenantID types.TenantID, uid types.Uid, sid, nodeID string) error {
 	if groupMsgRuntime == nil || !tenantID.IsValid() || uid.IsZero() || sid == "" {
 		return nil
@@ -753,6 +762,23 @@ func (r *redisGroupMessageRuntime) ClaimShortState(namespace, id string, ttl tim
 	return r.client.SetNX(context.Background(), r.shortStateKey(namespace, id), "1", ttl).Result()
 }
 
+func (r *redisGroupMessageRuntime) ClaimShortStateValue(namespace, id, value string, ttl time.Duration) (bool, bool, error) {
+	if ttl <= 0 {
+		ttl = time.Duration(r.cfg.ShortTTL) * time.Second
+	}
+	key := r.shortStateKey(namespace, id)
+	ctx := context.Background()
+	claimed, err := r.client.SetNX(ctx, key, value, ttl).Result()
+	if err != nil || claimed {
+		return claimed, false, err
+	}
+	existing, err := r.client.Get(ctx, key).Result()
+	if err != nil {
+		return false, false, err
+	}
+	return false, existing == value, nil
+}
+
 func (r *redisGroupMessageRuntime) hotSeqIDs(tenantID types.TenantID, topic string, opts *types.QueryOpt, limit int) ([]int64, bool, error) {
 	if opts != nil && len(opts.IdRanges) > 0 {
 		seqs := expandRanges(opts.IdRanges, limit)