初始提交：OCI 面板后端（含 GenAI 网关一期）

internal/api/realip.go

@@ -0,0 +1,62 @@
+package api
+
+import (
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+
+	"oci-portal/internal/service"
+)
+
+// ctxRealIPKey 是真实IP中间件写入 gin.Context 的键。
+const ctxRealIPKey = "realIP"
+
+// RealIPMiddleware 按安全设置解析客户端真实 IP 写入上下文,
+// 全链路(IP 限速 / 登录守卫 / 系统日志留痕)统一消费;gin 内置
+// TrustedProxies 已禁用,信任边界完全由该配置决定。
+func RealIPMiddleware(settings *service.SettingService) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.Set(ctxRealIPKey, resolveRealIP(c.Request, settings.SecurityCached().RealIPHeader))
+		c.Next()
+	}
+}
+
+// requestIP 取中间件解析的真实 IP;未经中间件(单测直调 handler)时回退 RemoteAddr。
+func requestIP(c *gin.Context) string {
+	if ip := c.GetString(ctxRealIPKey); ip != "" {
+		return ip
+	}
+	return remoteHost(c.Request)
+}
+
+// resolveRealIP 依配置头解析:X-Forwarded-For 取链尾(直连反代的对端,
+// 反代会把对端追加到链尾,链首可被客户端伪造);X-Real-IP 等单值头直取;
+// 头缺失或未配置(直连部署)回退 RemoteAddr。
+func resolveRealIP(r *http.Request, header string) string {
+	switch header {
+	case "":
+	case "X-Forwarded-For":
+		if v := r.Header.Get(header); v != "" {
+			parts := strings.Split(v, ",")
+			if ip := strings.TrimSpace(parts[len(parts)-1]); ip != "" {
+				return ip
+			}
+		}
+	default:
+		if ip := strings.TrimSpace(r.Header.Get(header)); ip != "" {
+			return ip
+		}
+	}
+	return remoteHost(r)
+}
+
+// remoteHost 取 RemoteAddr 的 host 部分。
+func remoteHost(r *http.Request) string {
+	host, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		return r.RemoteAddr
+	}
+	return host
+}