fix(backend): enforce port range restrictions in federation mode (#125)

Added dual-layer port range enforcement for federation sharing:

Server-side (Provider):
- federationRuntimeApplyRole: validate runtime.Port against share range
- validateFederationCommandPorts: hardened against malformed JSON bypass
- New helpers: validateRemoteNodePort, remoteNodePortRange

Client-side (Consumer):
- prepareTunnelCreateState: pre-check ports for remote nodes
- tunnelCreate type=1: validate targetPort for remote entry
- forwardCreate/Update/BatchChangeTunnel: port range validation

Prevents consumers from using arbitrary ports outside provider's allowed range.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

go-backend/internal/http/handler/mutations.go

@@ -545,6 +545,11 @@ func (h *Handler) tunnelCreate(w http.ResponseWriter, r *http.Request) {
 				}
 
 				if targetPort > 0 && targetAddr != "" {
+					inNodeRec := runtimeState.Nodes[firstNodeID]
+					if err := validateRemoteNodePort(inNodeRec, targetPort); err != nil {
+						response.WriteJSON(w, response.ErrDefault(err.Error()))
+						return
+					}
 					domainCfg, _ := h.repo.GetConfigByName("panel_domain")
 					localDomain := ""
 					if domainCfg != nil {
@@ -1105,6 +1110,17 @@ func (h *Handler) forwardCreate(w http.ResponseWriter, r *http.Request) {
 	if port <= 0 {
 		port = 10000
 	}
+	entryNodes, _ := h.tunnelEntryNodeIDs(tunnelID)
+	for _, nodeID := range entryNodes {
+		node, nodeErr := h.getNodeRecord(nodeID)
+		if nodeErr != nil {
+			continue
+		}
+		if err := validateRemoteNodePort(node, port); err != nil {
+			response.WriteJSON(w, response.ErrDefault(err.Error()))
+			return
+		}
+	}
 	now := time.Now().UnixMilli()
 	inx := nextIndex(h.repo.DB(), "forward")
 	var userName string
@@ -1126,7 +1142,6 @@ func (h *Handler) forwardCreate(w http.ResponseWriter, r *http.Request) {
 		response.WriteJSON(w, response.Err(-2, err.Error()))
 		return
 	}
-	entryNodes, _ := h.tunnelEntryNodeIDs(tunnelID)
 	for _, nodeID := range entryNodes {
 		_, _ = tx.Exec(`INSERT INTO forward_port(forward_id, node_id, port) VALUES(?, ?, ?)`, forwardID, nodeID, port)
 	}
@@ -1216,6 +1231,17 @@ func (h *Handler) forwardUpdate(w http.ResponseWriter, r *http.Request) {
 			port = h.pickTunnelPort(tunnelID)
 		}
 	}
+	fwdEntryNodes, _ := h.tunnelEntryNodeIDs(tunnelID)
+	for _, nodeID := range fwdEntryNodes {
+		node, nodeErr := h.getNodeRecord(nodeID)
+		if nodeErr != nil {
+			continue
+		}
+		if err := validateRemoteNodePort(node, port); err != nil {
+			response.WriteJSON(w, response.ErrDefault(err.Error()))
+			return
+		}
+	}
 	now := time.Now().UnixMilli()
 	_, err = h.repo.DB().Exec(`
 		UPDATE forward SET name = ?, tunnel_id = ?, remote_addr = ?, strategy = ?, updated_time = ? WHERE id = ?
@@ -1540,6 +1566,22 @@ func (h *Handler) forwardBatchChangeTunnel(w http.ResponseWriter, r *http.Reques
 		if p <= 0 {
 			p = h.pickTunnelPort(req.TargetTunnelID)
 		}
+		bctEntryNodes, _ := h.tunnelEntryNodeIDs(req.TargetTunnelID)
+		portRangeOk := true
+		for _, nid := range bctEntryNodes {
+			nd, ndErr := h.getNodeRecord(nid)
+			if ndErr != nil {
+				continue
+			}
+			if validateRemoteNodePort(nd, p) != nil {
+				portRangeOk = false
+				break
+			}
+		}
+		if !portRangeOk {
+			fail++
+			continue
+		}
 		if err := h.replaceForwardPorts(id, req.TargetTunnelID, p); err != nil {
 			h.rollbackForwardMutation(forward, oldPorts)
 			fail++
@@ -2235,6 +2277,19 @@ func (h *Handler) prepareTunnelCreateState(tx *store.Tx, req map[string]interfac
 		state.Nodes[nodeID] = node
 	}
 
+	for _, outNode := range state.OutNodes {
+		if err := validateRemoteNodePort(state.Nodes[outNode.NodeID], outNode.Port); err != nil {
+			return nil, err
+		}
+	}
+	for _, hop := range state.ChainHops {
+		for _, chainNode := range hop {
+			if err := validateRemoteNodePort(state.Nodes[chainNode.NodeID], chainNode.Port); err != nil {
+				return nil, err
+			}
+		}
+	}
+
 	return state, nil
 }