Merge branch 'fix-private-snippet-api' into 'master'

Prevent information disclosure via snippet API

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/15580

See merge request !1958
Signed-off-by: Rémy Coutable <remy@rymai.me>

CHANGELOG

@@ -4,6 +4,7 @@ v 8.2.5
   - Fix a window.opener bug that could lead to XSS and open redirects
   - Prevent privilege escalation via "impersonate" feature
   - Prevent users from deleting Webhooks via API they do not own
+  - Prevent information disclosure via snippet API
 
 v 8.2.4
   - Bump Git version requirement to 2.7.4

app/finders/snippets_finder.rb

@@ -51,7 +51,7 @@ class SnippetsFinder
     snippets = project.snippets.fresh.non_expired
 
     if current_user
-      if project.team.member?(current_user.id)
+      if project.team.member?(current_user.id) || current_user.admin?
         snippets
       else
         snippets.public_and_internal

lib/api/project_snippets.rb

@@ -11,6 +11,11 @@ module API
           end
           not_found!
         end
+
+        def snippets_for_current_user
+          finder_params = { filter: :by_project, project: user_project }
+          SnippetsFinder.new.execute(current_user, finder_params)
+        end
       end
 
       # Get a project snippets
@@ -20,7 +25,7 @@ module API
       # Example Request:
       #   GET /projects/:id/snippets
       get ":id/snippets" do
-        present paginate(user_project.snippets), with: Entities::ProjectSnippet
+        present paginate(snippets_for_current_user), with: Entities::ProjectSnippet
       end
 
       # Get a project snippet
@@ -31,7 +36,7 @@ module API
       # Example Request:
       #   GET /projects/:id/snippets/:snippet_id
       get ":id/snippets/:snippet_id" do
-        @snippet = user_project.snippets.find(params[:snippet_id])
+        @snippet = snippets_for_current_user.find(params[:snippet_id])
         present @snippet, with: Entities::ProjectSnippet
       end
 
@@ -73,7 +78,7 @@ module API
       # Example Request:
       #   PUT /projects/:id/snippets/:snippet_id
       put ":id/snippets/:snippet_id" do
-        @snippet = user_project.snippets.find(params[:snippet_id])
+        @snippet = snippets_for_current_user.find(params[:snippet_id])
         authorize! :update_project_snippet, @snippet
 
         attrs = attributes_for_keys [:title, :file_name, :visibility_level]
@@ -97,7 +102,7 @@ module API
       #   DELETE /projects/:id/snippets/:snippet_id
       delete ":id/snippets/:snippet_id" do
         begin
-          @snippet = user_project.snippets.find(params[:snippet_id])
+          @snippet = snippets_for_current_user.find(params[:snippet_id])
           authorize! :update_project_snippet, @snippet
           @snippet.destroy
         rescue
@@ -113,7 +118,7 @@ module API
       # Example Request:
       #   GET /projects/:id/snippets/:snippet_id/raw
       get ":id/snippets/:snippet_id/raw" do
-        @snippet = user_project.snippets.find(params[:snippet_id])
+        @snippet = snippets_for_current_user.find(params[:snippet_id])
 
         env['api.format'] = :txt
         content_type 'text/plain'

spec/requests/api/project_snippets_spec.rb

+require 'rails_helper'
+
+describe API::API, api: true do
+  include ApiHelpers
+
+  describe 'GET /projects/:project_id/snippets/:id' do
+    # TODO (rspeicher): Deprecated; remove in 9.0
+    it 'always exposes expires_at as nil' do
+      admin = create(:admin)
+      snippet = create(:project_snippet, author: admin)
+
+      get api("/projects/#{snippet.project.id}/snippets/#{snippet.id}", admin)
+
+      expect(json_response).to have_key('expires_at')
+      expect(json_response['expires_at']).to be_nil
+    end
+  end
+
+  describe 'GET /projects/:project_id/snippets/' do
+    it 'all snippets available to team member' do
+      project = create(:project, :public)
+      user = create(:user)
+      project.team << [user, :developer]
+      public_snippet = create(:project_snippet, visibility_level: 20, project: project)
+      internal_snippet = create(:project_snippet, visibility_level: 10, project: project)
+      private_snippet = create(:project_snippet, visibility_level: 0, project: project)
+
+      get api("/projects/#{project.id}/snippets/", user)
+
+      expect(response.status).to eq(200)
+      expect(json_response.size).to eq(3)
+      expect(json_response.map{ |snippet| snippet['id']} ).to include(public_snippet.id, internal_snippet.id, private_snippet.id)
+    end
+
+    it 'hides private snippets from regular user' do
+      project = create(:project, :public)
+      user = create(:user)
+      create(:project_snippet, visibility_level: 0, project: project)
+
+      get api("/projects/#{project.id}/snippets/", user)
+      expect(response.status).to eq(200)
+      expect(json_response.size).to eq(0)
+    end
+  end
+
+  describe 'POST /projects/:project_id/snippets/' do
+    it 'creates a new snippet' do
+      admin = create(:admin)
+      project = create(:project)
+      params = {
+        title: 'Test Title',
+        file_name: 'test.rb',
+        code: 'puts "hello world"',
+        visibility_level: Gitlab::VisibilityLevel::PUBLIC
+      }
+
+      post api("/projects/#{project.id}/snippets/", admin), params
+
+      expect(response.status).to eq(201)
+      snippet = ProjectSnippet.find(json_response['id'])
+      expect(snippet.content).to eq(params[:code])
+      expect(snippet.title).to eq(params[:title])
+      expect(snippet.file_name).to eq(params[:file_name])
+      expect(snippet.visibility_level).to eq(params[:visibility_level])
+    end
+  end
+
+  describe 'PUT /projects/:project_id/snippets/:id/' do
+    it 'updates snippet' do
+      admin = create(:admin)
+      snippet = create(:project_snippet, author: admin)
+      new_content = 'New content'
+
+      put api("/projects/#{snippet.project.id}/snippets/#{snippet.id}/", admin), code: new_content
+
+      expect(response.status).to eq(200)
+      snippet.reload
+      expect(snippet.content).to eq(new_content)
+    end
+  end
+
+  describe 'DELETE /projects/:project_id/snippets/:id/' do
+    it 'deletes snippet' do
+      admin = create(:admin)
+      snippet = create(:project_snippet, author: admin)
+
+      delete api("/projects/#{snippet.project.id}/snippets/#{snippet.id}/", admin)
+
+      expect(response.status).to eq(200)
+    end
+  end
+
+  describe 'GET /projects/:project_id/snippets/:id/raw' do
+    it 'returns raw text' do
+      admin = create(:admin)
+      snippet = create(:project_snippet, author: admin)
+
+      get api("/projects/#{snippet.project.id}/snippets/#{snippet.id}/raw", admin)
+
+      expect(response.status).to eq(200)
+      expect(response.content_type).to eq 'text/plain'
+      expect(response.body).to eq(snippet.content)
+    end
+  end
+end

spec/requests/api/projects_spec.rb

@@ -11,9 +11,9 @@ describe API::API, api: true  do
   let(:project) { create(:project, creator_id: user.id, namespace: user.namespace) }
   let(:project2) { create(:project, path: 'project2', creator_id: user.id, namespace: user.namespace) }
   let(:project3) { create(:project, path: 'project3', creator_id: user.id, namespace: user.namespace) }
-  let(:snippet) { create(:project_snippet, author: user, project: project, title: 'example') }
-  let(:project_member) { create(:project_member, user: user, project: project, access_level: ProjectMember::MASTER) }
-  let(:project_member2) { create(:project_member, user: user3, project: project, access_level: ProjectMember::DEVELOPER) }
+  let(:snippet) { create(:project_snippet, visibility_level: 20, author: user, project: project, title: 'example') }
+  let(:project_member) { create(:project_member, access_level: ProjectMember::MASTER, user: user, project: project) }
+  let(:project_member2) { create(:project_member, access_level: ProjectMember::DEVELOPER, user: user3, project: project) }
   let(:user4) { create(:user) }
   let(:project3) do
     create(:project,