Files
tamabox/internal/security/autoban/autoban.go
T
tamakyi e3e59e7c69 chore: baseline snapshot before moderation-strictness feature
Repo .git was damaged (refs/ missing, index truncated, object store near-empty).
Repaired via git init (rebuilt refs), stale index preserved as .git/index.corrupt-20260910.bak,
then full worktree committed as a rollback baseline.
2026-09-10 10:56:27 +08:00

299 lines
8.5 KiB
Go

// Package autoban 提供 fail2ban 风格的自动临时封禁:检测批量扫描/探测特征后
// 临时封禁来源 IP,并可回调发送告警。纯标准库实现,便于独立测试与复用。
package autoban
import (
"strings"
"sync"
"time"
)
// 探测事件类型
const (
KindNone = 0 // 无探测特征
KindSensitive = 1 // 命中敏感路径
KindNotFound = 2 // 404 响应(未命中敏感路径)
)
// 默认阈值/窗口(Options 未配置或为 0 时兜底)。
const (
DefaultWindowSeconds = 60
DefaultDurationMinutes = 15
DefaultThresholdSensitive = 10
DefaultThreshold404 = 20
pathSampleMax = 6
)
// Options 自动封禁配置。
type Options struct {
Enabled bool
// TrackNotFound 是否把 KindNotFound(未注册路径的 404)计入封禁统计。
// 默认 false:正常业务路径一律放行,仅敏感扫描特征路径参与计数封禁,
// 避免共享出口下正常访问被 404 探测连坐误伤(详见 conf.Security.BanTrackNotFound)。
TrackNotFound bool
ThresholdSensitive int // 窗口内敏感路径命中次数
Threshold404 int // 窗口内 404 次数
Window time.Duration // 统计窗口
Duration time.Duration // 封禁时长
AlertEmail string // 告警收件人(留空不发送)
SendAlert func(ip string, paths []string, durationMinutes int) error // 告警发送函数(nil 则不发送)
}
// sensitivePaths 常见后台/配置/漏洞探测路径特征(忽略大小写,完整段前缀匹配)。
// 注意:前缀匹配抓不到 //xxx/wp-includes/wlwmanifest.xml 这类"目录枚举变体"(敏感段
// 出现在路径中部),需要与 sensitiveFragments(任意位置子串)配合使用。
var sensitivePaths = []string{
"/admin", "/wp-admin", "/wp-login.php", "/wp-content", "/wordpress",
"/administrator", "/manager", "/cpanel", "/plesk",
"/.env", "/.git", "/.aws", "/.ssh", "/.svn", "/.hg", "/.htaccess",
"/config", "/configuration", "/backup", "/database", "/db",
"/actuator", "/swagger", "/api-docs", "/openapi", "/v2/api-docs",
"/phpmyadmin", "/pma", "/mysql", "/server-status", "/server-info",
"/shell", "/webshell", "/cmd", "/eval", "/hack", "/shell.php",
"/login.php", "/admin.php", "/index.php", "/console", "/vendor",
}
// sensitiveFragments 任意位置命中即算敏感的"强指纹"(忽略大小写,子串匹配)。
// 与 sensitivePaths 互补:捕获 /<枚举前缀>/wp-includes/wlwmanifest.xml、//wp/xmlrpc.php
// 等前缀匹配失效的变体。仅收录业务 URL 空间(/、/_/、/user、/api/v1、/vote、/explore、
// /i18n、/static…)绝不可能出现的 WordPress 特征,确保不误伤正常路径。
var sensitiveFragments = []string{
"/wp-includes/", "/wp-json/", "/wp-cron.php", "/wp-trackback.php",
"/wp-admin", "/wp-content", "/wp-login.php", "/wlwmanifest.xml",
"/xmlrpc.php", "/wordpress",
}
type probeEvent struct {
at time.Time
kind int
}
type probeStat struct {
events []probeEvent
sensitive int
notFound int
paths []string // 命中路径样本(告警用)
}
// Banner 自动封禁器。方法并发安全。
type Banner struct {
mu sync.Mutex
probes map[string]*probeStat
banned map[string]time.Time
alerted map[string]bool
thresholdSensitive int
threshold404 int
trackNotFound bool
window time.Duration
duration time.Duration
alertEmail string
sendAlert func(ip string, paths []string, durationMinutes int) error
enabled bool
}
// New 按配置创建封禁器并注册全局清理。
func New(opts Options) *Banner {
window := opts.Window
if window <= 0 {
window = DefaultWindowSeconds * time.Second
}
duration := opts.Duration
if duration <= 0 {
duration = DefaultDurationMinutes * time.Minute
}
sensitive := opts.ThresholdSensitive
if sensitive <= 0 {
sensitive = DefaultThresholdSensitive
}
notFound := opts.Threshold404
if notFound <= 0 {
notFound = DefaultThreshold404
}
b := &Banner{
probes: make(map[string]*probeStat),
banned: make(map[string]time.Time),
alerted: make(map[string]bool),
thresholdSensitive: sensitive,
threshold404: notFound,
trackNotFound: opts.TrackNotFound,
window: window,
duration: duration,
alertEmail: strings.TrimSpace(opts.AlertEmail),
sendAlert: opts.SendAlert,
enabled: opts.Enabled,
}
register(b)
return b
}
// Record 记录一次探测事件,达到阈值时封禁 IP 并触发一次告警。
func (b *Banner) Record(ip, path string, kind int) {
if !b.enabled || ip == "" || kind == KindNone {
return
}
// 404 计数默认关闭(正常业务路径一律放行,仅敏感扫描特征参与封禁):
// 只有显式开启 TrackNotFound 时才把未注册路径的 404 计入统计。
if kind == KindNotFound && !b.trackNotFound {
return
}
b.mu.Lock()
defer b.mu.Unlock()
now := time.Now()
cutoff := now.Add(-b.window)
st := b.probes[ip]
if st == nil {
st = &probeStat{}
b.probes[ip] = st
}
// 滚动清理过期事件并重算计数
valid := st.events[:0]
sensitive, notFound := 0, 0
for _, e := range st.events {
if e.at.After(cutoff) {
valid = append(valid, e)
if e.kind == KindSensitive {
sensitive++
} else if e.kind == KindNotFound {
notFound++
}
}
}
valid = append(valid, probeEvent{at: now, kind: kind})
if kind == KindSensitive {
sensitive++
} else {
notFound++
}
st.events = valid
st.sensitive = sensitive
st.notFound = notFound
if len(st.paths) < pathSampleMax && path != "" {
st.paths = append(st.paths, path)
}
if sensitive < b.thresholdSensitive && notFound < b.threshold404 {
return
}
// 已达阈值:封禁(已在封禁中则跳过)
if until, ok := b.banned[ip]; ok && until.After(now) {
return
}
until := now.Add(b.duration)
b.banned[ip] = until
// 告警(每 IP 仅一次)
if b.alertEmail != "" && b.sendAlert != nil && !b.alerted[ip] {
b.alerted[ip] = true
sample := append([]string{}, st.paths...)
dur := int(b.duration.Minutes())
go func() {
_ = b.sendAlert(ip, sample, dur)
}()
}
}
// IsBanned 判断 IP 是否处于封禁期;到期自动解除。
func (b *Banner) IsBanned(ip string) bool {
if !b.enabled || ip == "" {
return false
}
b.mu.Lock()
defer b.mu.Unlock()
if until, ok := b.banned[ip]; ok {
if until.After(time.Now()) {
return true
}
delete(b.banned, ip)
}
return false
}
// IsSensitivePath 判断路径是否命中敏感探测特征(忽略大小写)。
// 命中条件:① 与 sensitivePaths 完整段前缀匹配(/admin、/.env 等);
// ② 包含 sensitiveFragments 强指纹子串(wp-includes/xmlrpc.php 等 WordPress 探测面,
//
// 覆盖 // 双斜杠与目录枚举变体)。
func IsSensitivePath(p string) bool {
lower := strings.ToLower(p)
for _, s := range sensitivePaths {
if lower == s || strings.HasPrefix(lower, s+"/") {
return true
}
}
for _, f := range sensitiveFragments {
if strings.Contains(lower, f) {
return true
}
}
return false
}
// ---------- 全局注册与清理 ----------
var (
bannersMu sync.Mutex
banners = make(map[*Banner]struct{})
bannersOnce sync.Once
)
func register(b *Banner) {
bannersMu.Lock()
banners[b] = struct{}{}
bannersMu.Unlock()
bannersOnce.Do(func() {
go func() {
for {
time.Sleep(2 * time.Minute)
bannersMu.Lock()
for b := range banners {
b.cleanup()
}
bannersMu.Unlock()
}
}()
})
}
// cleanup 定期清理过期探测记录与已到期封禁(防止内存膨胀)。
func (b *Banner) cleanup() {
b.mu.Lock()
defer b.mu.Unlock()
now := time.Now()
cutoff := now.Add(-b.window)
for ip, st := range b.probes {
if len(st.events) == 0 || st.events[len(st.events)-1].at.Before(cutoff) {
delete(b.probes, ip)
continue
}
valid := st.events[:0]
sensitive, notFound := 0, 0
for _, e := range st.events {
if e.at.After(cutoff) {
valid = append(valid, e)
if e.kind == KindSensitive {
sensitive++
} else if e.kind == KindNotFound {
notFound++
}
}
}
st.events = valid
st.sensitive = sensitive
st.notFound = notFound
}
for ip, until := range b.banned {
if !until.After(now) {
delete(b.banned, ip)
}
}
}