Change method to prevent forbidden directory traversal. Ref #1894

gns3server/api/routes/compute/projects.py

@@ -19,6 +19,7 @@ API routes for projects.
 """
 
 import os
+import urllib.parse
 
 import logging
 
@@ -198,6 +199,7 @@ async def get_compute_project_file(file_path: str, project: Project = Depends(de
     Get a file from a project.
     """
 
+    file_path = urllib.parse.unquote(file_path)
     path = os.path.normpath(file_path)
 
     # Raise error if user try to escape
@@ -214,6 +216,7 @@ async def get_compute_project_file(file_path: str, project: Project = Depends(de
 @router.post("/projects/{project_id}/files/{file_path:path}", status_code=status.HTTP_204_NO_CONTENT)
 async def write_compute_project_file(file_path: str, request: Request, project: Project = Depends(dep_project)) -> None:
 
+    file_path = urllib.parse.unquote(file_path)
     path = os.path.normpath(file_path)
 
     # Raise error if user try to escape

gns3server/api/routes/controller/projects.py

@@ -24,6 +24,7 @@ import tempfile
 import zipfile
 import aiofiles
 import time
+import urllib.parse
 
 import logging
 
@@ -369,7 +370,8 @@ async def get_file(file_path: str, project: Project = Depends(dep_project)) -> F
     Return a file from a project.
     """
 
-    path = os.path.normpath(file_path).strip("/")
+    file_path = urllib.parse.unquote(file_path)
+    path = os.path.normpath(file_path)
 
     # Raise error if user try to escape
     if not is_safe_path(path, project.path):
@@ -388,7 +390,8 @@ async def write_file(file_path: str, request: Request, project: Project = Depend
     Write a file from a project.
     """
 
-    path = os.path.normpath(file_path).strip("/")
+    file_path = urllib.parse.unquote(file_path)
+    path = os.path.normpath(file_path)
 
     # Raise error if user try to escape
     if not is_safe_path(path, project.path):

gns3server/utils/path.py

@@ -17,6 +17,7 @@
 
 import os
 
+from pathlib import Path
 from fastapi import HTTPException, status
 from ..config import Config
 
@@ -37,15 +38,14 @@ def get_default_project_directory():
     return path
 
 
-def is_safe_path(file_path, directory):
+def is_safe_path(file_path: str, basedir: str) -> bool:
     """
     Check that file path is safe.
     (the file is stored inside directory or one of its sub-directory)
     """
 
-    requested_path = os.path.abspath(file_path)
-    common_prefix = os.path.commonprefix([requested_path, directory])
-    return common_prefix != directory
+    test_path = (Path(basedir) / file_path).resolve()
+    return Path(basedir).resolve() in test_path.resolve().parents
 
 
 def check_path_allowed(path):

tests/api/routes/compute/test_dynamips_nodes.py

@@ -186,7 +186,23 @@ async def test_upload_image(app: FastAPI, client: AsyncClient, images_dir: str)
         assert checksum == "033bd94b1168d7e4f0d644c3c95e35bf"
 
 
-async def test_download_image_escape(app: FastAPI, client: AsyncClient, tmpdir) -> None:
+async def test_upload_image_forbidden_location(app: FastAPI, client: AsyncClient) -> None:
+
+    file_path = "%2e%2e/hello"
+    response = await client.post(app.url_path_for("upload_dynamips_image", filename=file_path), content=b"TEST")
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
+async def test_download_image(app: FastAPI, client: AsyncClient, images_dir: str) -> None:
+
+    response = await client.post(app.url_path_for("upload_dynamips_image", filename="test3"), content=b"TEST")
+    assert response.status_code == status.HTTP_204_NO_CONTENT
+
+    response = await client.get(app.url_path_for("download_dynamips_image", filename="test3"))
+    assert response.status_code == status.HTTP_200_OK
+
+
+async def test_download_image_forbidden(app: FastAPI, client: AsyncClient, tmpdir) -> None:
 
     file_path = "foo/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd"
     response = await client.get(app.url_path_for("download_dynamips_image", filename=file_path))

tests/api/routes/compute/test_iou_nodes.py

@@ -415,7 +415,23 @@ async def test_upload_image(app: FastAPI, client: AsyncClient, tmpdir) -> None:
         assert checksum == "033bd94b1168d7e4f0d644c3c95e35bf"
 
 
-async def test_download_image_escape(app: FastAPI, client: AsyncClient, tmpdir) -> None:
+async def test_upload_image_forbidden_location(app: FastAPI, client: AsyncClient) -> None:
+
+    file_path = "%2e%2e/hello"
+    response = await client.post(app.url_path_for("upload_dynamips_image", filename=file_path), content=b"TEST")
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
+async def test_download_image(app: FastAPI, client: AsyncClient, images_dir: str) -> None:
+
+    response = await client.post(app.url_path_for("upload_dynamips_image", filename="test3"), content=b"TEST")
+    assert response.status_code == status.HTTP_204_NO_CONTENT
+
+    response = await client.get(app.url_path_for("download_dynamips_image", filename="test3"))
+    assert response.status_code == status.HTTP_200_OK
+
+
+async def test_download_image_forbidden(app: FastAPI, client: AsyncClient, tmpdir) -> None:
 
     file_path = "foo/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd"
     response = await client.get(app.url_path_for("download_iou_image", filename=file_path))

tests/api/routes/compute/test_projects.py

@@ -179,6 +179,21 @@ async def test_get_file(app: FastAPI, client: AsyncClient, config, tmpdir) -> No
     assert response.status_code == status.HTTP_404_NOT_FOUND
 
 
+async def test_get_file_forbidden_location(app: FastAPI, client: AsyncClient, config, tmpdir) -> None:
+
+    config.settings.Server.projects_path = str(tmpdir)
+    project = ProjectManager.instance().create_project(project_id="01010203-0405-0607-0809-0a0b0c0d0e0b")
+    file_path = "foo/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd"
+    response = await client.get(
+        app.url_path_for(
+            "get_compute_project_file",
+            project_id=project.id,
+            file_path=file_path
+        )
+    )
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
 async def test_write_file(app: FastAPI, client: AsyncClient, config, tmpdir) -> None:
 
     config.settings.Server.projects_path = str(tmpdir)
@@ -196,3 +211,15 @@ async def test_write_file(app: FastAPI, client: AsyncClient, config, tmpdir) ->
                                                   project_id=project.id,
                                                   file_path="../hello"))
     assert response.status_code == status.HTTP_404_NOT_FOUND
+
+
+async def test_write_file_forbidden_location(app: FastAPI, client: AsyncClient, config, tmpdir) -> None:
+
+    config.settings.Server.projects_path = str(tmpdir)
+    project = ProjectManager.instance().create_project(project_id="01010203-0405-0607-0809-0a0b0c0d0e0b")
+
+    file_path = "%2e%2e/hello"
+    response = await client.post(app.url_path_for("write_compute_project_file",
+                                                  project_id=project.id,
+                                                  file_path=file_path), content=b"world")
+    assert response.status_code == status.HTTP_403_FORBIDDEN

tests/api/routes/compute/test_qemu_nodes.py

@@ -388,15 +388,23 @@ async def test_upload_image_ova(app: FastAPI, client: AsyncClient, tmpdir:str) -
         assert checksum == "033bd94b1168d7e4f0d644c3c95e35bf"
 
 
-async def test_upload_image_forbiden_location(app: FastAPI, client: AsyncClient, tmpdir: str) -> None:
+async def test_upload_image_forbidden_location(app: FastAPI, client: AsyncClient, tmpdir: str) -> None:
 
-    with patch("gns3server.compute.Qemu.get_images_directory", return_value=str(tmpdir)):
-        response = await client.post(app.url_path_for("upload_qemu_image",
-                                                      filename="/qemu/images/../../test2"), content=b"TEST")
-        assert response.status_code == status.HTTP_403_FORBIDDEN
+    response = await client.post(app.url_path_for("upload_qemu_image",
+                                                  filename="/qemu/images/../../test2"), content=b"TEST")
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
+async def test_download_image(app: FastAPI, client: AsyncClient, images_dir: str) -> None:
+
+    response = await client.post(app.url_path_for("upload_qemu_image", filename="test3"), content=b"TEST")
+    assert response.status_code == status.HTTP_204_NO_CONTENT
+
+    response = await client.get(app.url_path_for("download_qemu_image", filename="test3"))
+    assert response.status_code == status.HTTP_200_OK
 
 
-async def test_download_image_escape(app: FastAPI, client: AsyncClient, tmpdir) -> None:
+async def test_download_image_forbidden_location(app: FastAPI, client: AsyncClient, tmpdir) -> None:
 
     file_path = "foo/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd"
     response = await client.get(app.url_path_for("download_qemu_image", filename=file_path))

tests/api/routes/controller/test_projects.py

@@ -330,6 +330,13 @@ async def test_get_file(app: FastAPI, client: AsyncClient, project: Project) ->
     assert response.status_code == status.HTTP_404_NOT_FOUND
 
 
+async def test_get_file_forbidden_location(app: FastAPI, client: AsyncClient, project: Project) -> None:
+
+    file_path = "foo/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd"
+    response = await client.get(app.url_path_for("get_file", project_id=project.id, file_path=file_path))
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
 async def test_write_file(app: FastAPI, client: AsyncClient, project: Project) -> None:
 
     response = await client.post(app.url_path_for("write_file", project_id=project.id, file_path="hello"),
@@ -343,6 +350,14 @@ async def test_write_file(app: FastAPI, client: AsyncClient, project: Project) -
     assert response.status_code == status.HTTP_404_NOT_FOUND
 
 
+async def test_write_file_forbidden_location(app: FastAPI, client: AsyncClient, project: Project) -> None:
+
+    file_path = "%2e%2e/hello"
+    response = await client.post(app.url_path_for("write_file", project_id=project.id, file_path=file_path),
+                                 content=b"world")
+    assert response.status_code == status.HTTP_403_FORBIDDEN
+
+
 async def test_write_and_get_file_with_leading_slashes_in_filename(
         app: FastAPI,
         client: AsyncClient,
@@ -350,11 +365,10 @@ async def test_write_and_get_file_with_leading_slashes_in_filename(
 
     response = await client.post(app.url_path_for("write_file", project_id=project.id, file_path="//hello"),
                                  content=b"world")
-    assert response.status_code == status.HTTP_204_NO_CONTENT
+    assert response.status_code == status.HTTP_403_FORBIDDEN
 
     response = await client.get(app.url_path_for("get_file", project_id=project.id, file_path="//hello"))
-    assert response.status_code == status.HTTP_200_OK
-    assert response.content == b"world"
+    assert response.status_code == status.HTTP_403_FORBIDDEN
 
 
 async def test_import(app: FastAPI, client: AsyncClient, tmpdir, controller: Controller) -> None: