sync from local backup

2026-08-05 23:59:15 +08:00
commit d48ec1747c
358 changed files with 34384 additions and 0 deletions
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+import logging
+import dns.resolver
+from django.core.cache import caches
+
+logger = logging.getLogger(__name__)
+default_cache = caches['default']
+
+MX_CACHE_TTL = 3600  # MX 验证结果缓存1小时，避免每次请求都做慢速DNS查询
+
+# 常用邮箱域名白名单：大概率可正常收发，直接放行，无需DNS查询
+COMMON_EMAIL_DOMAINS = {
+    'qq.com', 'foxmail.com', '163.com', '126.com', 'yeah.net',
+    '139.com', '189.cn', 'sina.com', 'sohu.com', '21cn.com',
+    'gmail.com', 'googlemail.com', 'outlook.com', 'hotmail.com',
+    'live.com', 'msn.com', 'icloud.com', 'me.com', 'yahoo.com',
+    'proton.me', 'protonmail.com', 'gmx.com', 'gmx.net', 'aol.com', 'zoho.com',
+}
+
+
+def validate_email_mx(email):
+    """验证邮箱域名是否有MX记录（通过DNS MX查询），排除 null MX (MX 0 .) 的情况"""
+    try:
+        domain = email.split('@')[1].lower()
+    except IndexError:
+        return False
+
+    # 常用邮箱域名直接放行，免DNS查询
+    if domain in COMMON_EMAIL_DOMAINS:
+        return True
+
+    cache_key = f'mx_valid_{domain}'
+    try:
+        cached = default_cache.get(cache_key)
+        if cached is not None:
+            return cached
+    except Exception:
+        pass
+
+    valid = _query_mx(domain)
+    try:
+        default_cache.set(cache_key, valid, timeout=MX_CACHE_TTL)
+    except Exception:
+        pass
+    return valid
+
+
+def _query_mx(domain):
+    try:
+        answers = dns.resolver.resolve(domain, 'MX')
+        # 检查是否是 null MX (MX 0 .) — 域名明确拒绝收件
+        for answer in answers:
+            exchange = answer.exchange.to_text().rstrip('.')
+            if exchange:  # 有真实的邮件服务器
+                return True
+        # 所有 MX 记录都指向空（null MX），表示不接受邮件
+        logger.warning(f'[Email] Domain has null MX (rejects mail): {domain}')
+        return False
+    except (dns.resolver.NoAnswer, dns.resolver.NXDOMAIN, dns.resolver.NoNameservers):
+        logger.warning(f'[Email] No MX record found for domain: {domain}')
+        return False
+    except Exception as e:
+        logger.warning(f'[Email] MX record check failed: domain={domain}, error={str(e)}')
+        return False