fix: block private image proxy targets

2026-07-21 12:41:59 +08:00 · 2026-05-24 07:18:51 +08:00
parent 0273adc61c
commit 0b7854a0af
4 changed files with 191 additions and 2 deletions
--- a/tests/test_security_utils.py
+++ b/tests/test_security_utils.py
@@ -0,0 +1,126 @@
+import socket
+from unittest import TestCase
+from unittest.mock import patch
+
+from app.utils.security import SecurityUtils
+
+
+class SecurityUtilsTest(TestCase):
+
+    def test_is_safe_url_keeps_default_allowlist_behavior(self):
+        """
+        默认 URL 校验保持历史 allowlist 行为，避免影响非代理调用方。
+        """
+        self.assertTrue(
+            SecurityUtils.is_safe_url(
+                "http://192.168.1.50:8096/secret.png",
+                {"http://192.168.1.50:8096"},
+            )
+        )
+
+    def test_is_safe_url_blocks_private_literal_ip_when_enabled(self):
+        """
+        启用 SSRF 防护时，即使内网 IP 命中 allowlist 也不能放行。
+        """
+        self.assertFalse(
+            SecurityUtils.is_safe_url(
+                "http://192.168.1.50:8096/secret.png",
+                {"http://192.168.1.50:8096"},
+                block_private=True,
+            )
+        )
+
+    def test_is_safe_url_blocks_loopback_dns_result_when_enabled(self):
+        """
+        主机名解析到回环地址时必须拒绝，防止通过域名绕过内网地址拦截。
+        """
+        with patch(
+            "app.utils.security.socket.getaddrinfo",
+            return_value=[
+                (
+                    socket.AF_INET,
+                    socket.SOCK_STREAM,
+                    0,
+                    "",
+                    ("127.0.0.1", 0),
+                )
+            ],
+        ):
+            self.assertFalse(
+                SecurityUtils.is_safe_url(
+                    "http://internal.example.com/secret.png",
+                    {"example.com"},
+                    block_private=True,
+                )
+            )
+
+    def test_is_safe_url_blocks_mixed_public_and_private_dns_results(self):
+        """
+        同一域名只要存在任一非公网解析结果，就不能作为图片代理目标。
+        """
+        with patch(
+            "app.utils.security.socket.getaddrinfo",
+            return_value=[
+                (
+                    socket.AF_INET,
+                    socket.SOCK_STREAM,
+                    0,
+                    "",
+                    ("93.184.216.34", 0),
+                ),
+                (
+                    socket.AF_INET,
+                    socket.SOCK_STREAM,
+                    0,
+                    "",
+                    ("10.0.0.8", 0),
+                ),
+            ],
+        ):
+            self.assertFalse(
+                SecurityUtils.is_safe_url(
+                    "https://assets.example.com/poster.jpg",
+                    {"example.com"},
+                    block_private=True,
+                )
+            )
+
+    def test_is_safe_url_allows_public_dns_result_when_enabled(self):
+        """
+        域名解析结果全部为公网地址且命中 allowlist 时继续允许访问。
+        """
+        with patch(
+            "app.utils.security.socket.getaddrinfo",
+            return_value=[
+                (
+                    socket.AF_INET,
+                    socket.SOCK_STREAM,
+                    0,
+                    "",
+                    ("93.184.216.34", 0),
+                )
+            ],
+        ):
+            self.assertTrue(
+                SecurityUtils.is_safe_url(
+                    "https://assets.example.com/poster.jpg",
+                    {"example.com"},
+                    block_private=True,
+                )
+            )
+
+    def test_is_safe_url_rejects_dns_resolution_failure_when_enabled(self):
+        """
+        SSRF 防护无法确认目标地址时按失败处理，避免解析异常时继续请求。
+        """
+        with patch(
+            "app.utils.security.socket.getaddrinfo",
+            side_effect=socket.gaierror,
+        ):
+            self.assertFalse(
+                SecurityUtils.is_safe_url(
+                    "https://assets.example.com/poster.jpg",
+                    {"example.com"},
+                    block_private=True,
+                )
+            )