merge fix/agent-public-addr: master-observed public IP resolution (V1.0.1)

internal/web/controller/agent.go

@@ -6,7 +6,9 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"errors"
+	"net"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/mhsanaei/3x-ui/v3/internal/config"
@@ -100,6 +102,69 @@ func (a *AgentController) findAgent(token string) (*model.AgentNode, bool) {
 	return &agent, true
 }
 
+// requestSourceIP extracts the real source IP of an agent request.
+// Agents reach the master through Cloudflare, so the TCP peer is a CF
+// edge and the agent's own address travels in CF-Connecting-IP; the
+// first X-Forwarded-For hop is the next best signal, and the transport
+// RemoteAddr is the direct-connection fallback. Only literal IPs are
+// accepted — anything unparsable falls through to the next source.
+func requestSourceIP(c *gin.Context) net.IP {
+	var candidates []string
+	if v := c.GetHeader("CF-Connecting-IP"); v != "" {
+		candidates = append(candidates, v)
+	}
+	if v := c.GetHeader("X-Forwarded-For"); v != "" {
+		candidates = append(candidates, strings.Split(v, ",")[0])
+	}
+	if host, _, err := net.SplitHostPort(c.Request.RemoteAddr); err == nil {
+		candidates = append(candidates, host)
+	} else {
+		candidates = append(candidates, c.Request.RemoteAddr)
+	}
+	for _, cand := range candidates {
+		if ip := net.ParseIP(strings.TrimSpace(cand)); ip != nil {
+			return ip
+		}
+	}
+	return nil
+}
+
+// captureSeenIP records the source address of an authenticated agent
+// request on the agent row (SeenIPv4/SeenIPv6). This is the master's
+// view of the agent's public side: for a NAT'd agent it is the only
+// place the public address ever appears. Writes are change-only —
+// traffic reports land every ~10s and the address almost never moves,
+// so an unchanged address must not turn into a DB write per request.
+func (a *AgentController) captureSeenIP(c *gin.Context, agent *model.AgentNode) {
+	ip := requestSourceIP(c)
+	if ip == nil || agent == nil {
+		return
+	}
+	updates := map[string]any{"seen_ip_at": time.Now().UnixMilli()}
+	if v4 := ip.To4(); v4 != nil {
+		if agent.SeenIPv4 == v4.String() {
+			return
+		}
+		updates["seen_ipv4"] = v4.String()
+	} else {
+		if agent.SeenIPv6 == ip.String() {
+			return
+		}
+		updates["seen_ipv6"] = ip.String()
+	}
+	if err := database.GetDB().Model(&model.AgentNode{}).
+		Where("id = ?", agent.Id).Updates(updates).Error; err != nil {
+		return
+	}
+	if v, ok := updates["seen_ipv4"]; ok {
+		agent.SeenIPv4 = v.(string)
+	}
+	if v, ok := updates["seen_ipv6"]; ok {
+		agent.SeenIPv6 = v.(string)
+	}
+	agent.SeenIPAt = updates["seen_ip_at"].(int64)
+}
+
 func (a *AgentController) touchAgent(id uint, name string) {
 	updates := map[string]any{"last_seen": time.Now().UnixMilli()}
 	if name != "" {
@@ -133,6 +198,7 @@ func (a *AgentController) register(c *gin.Context) {
 		c.JSON(401, gin.H{"message": "unknown token"})
 		return
 	}
+	a.captureSeenIP(c, agent)
 	a.touchAgent(uint(agent.Id), req.Name)
 	logger.Infof("Agent registered: %s (token %s...)", req.Name, agent.TokenPrefix)
 	jsonObj(c, gin.H{"message": "registered"}, nil)
@@ -257,6 +323,7 @@ func (a *AgentController) heartbeat(c *gin.Context) {
 		c.JSON(401, gin.H{"message": "unauthorized"})
 		return
 	}
+	a.captureSeenIP(c, agent)
 	// Telemetry is optional and best-effort: a body that fails to parse
 	// (or no body at all) must never fail the heartbeat itself.
 	var req struct {
@@ -286,6 +353,7 @@ func (a *AgentController) getConfig(c *gin.Context) {
 		c.JSON(401, gin.H{"message": "unauthorized"})
 		return
 	}
+	a.captureSeenIP(c, agent)
 	if agent.NodeID == nil {
 		c.JSON(409, gin.H{"message": "agent token is not bound to a node"})
 		return
@@ -344,6 +412,7 @@ func (a *AgentController) reportTraffic(c *gin.Context) {
 		c.JSON(401, gin.H{"message": "unauthorized"})
 		return
 	}
+	a.captureSeenIP(c, agent)
 	var req agentTrafficReport
 	if err := c.ShouldBindJSON(&req); err != nil {
 		jsonMsg(c, "Invalid request", err)