From f82d549d26af89cba00005e1a1c9b721c076f7a0 Mon Sep 17 00:00:00 2001 From: Timothy Andrew Date: Wed, 7 Dec 2016 13:25:49 +0530 Subject: [PATCH] Accept environment variables from the `pre-receive` script. 1. Starting version 2.11, git changed the way the pre-receive flow works. - Previously, the new potential objects would be added to the main repo. If the pre-receive passes, the new objects stay in the repo but are linked up. If the pre-receive fails, the new objects stay orphaned in the repo, and are cleaned up during the next `git gc`. - In 2.11, the new potential objects are added to a temporary "alternate object directory", that git creates for this purpose. If the pre-receive passes, the objects from the alternate object directory are migrated to the main repo. If the pre-receive fails the alternate object directory is simply deleted. 2. In our workflow, the pre-recieve script (in `gitlab-shell) calls the `/allowed` endpoint, which calls out directly to git to perform various checks. These direct calls to git do _not_ have the necessary environment variables set which allow access to the "alternate object directory" (explained above). Therefore these calls to git are not able to access any of the new potential objects to be added during this push. 3. We fix this by accepting the relevant environment variables (GIT_ALTERNATE_OBJECT_DIRECTORIES, GIT_OBJECT_DIRECTORY) on the `/allowed` endpoint, and then include these environment variables while calling out to git. 4. This commit includes (whitelisted) these environment variables while making the "force push" check. A `Gitlab::Git::RevList` module is extracted to prevent `ForcePush` from being littered with these checks. --- lib/api/helpers/internal_helpers.rb | 8 ++++++++ lib/api/internal.rb | 6 +++++- lib/gitlab/checks/change_access.rb | 5 +++-- lib/gitlab/checks/force_push.rb | 4 ++-- lib/gitlab/git/rev_list.rb | 28 ++++++++++++++++++++++++++++ lib/gitlab/git_access.rb | 5 +++-- lib/gitlab/popen.rb | 4 ++-- 7 files changed, 51 insertions(+), 9 deletions(-) create mode 100644 lib/gitlab/git/rev_list.rb diff --git a/lib/api/helpers/internal_helpers.rb b/lib/api/helpers/internal_helpers.rb index eb223c1101d..e8975eb57e0 100644 --- a/lib/api/helpers/internal_helpers.rb +++ b/lib/api/helpers/internal_helpers.rb @@ -52,6 +52,14 @@ module API :push_code ] end + + def parse_allowed_environment_variables + return if params[:env].blank? + + JSON.parse(params[:env]) + + rescue JSON::ParserError + end end end end diff --git a/lib/api/internal.rb b/lib/api/internal.rb index 7087ce11401..db2d18f935d 100644 --- a/lib/api/internal.rb +++ b/lib/api/internal.rb @@ -32,7 +32,11 @@ module API if wiki? Gitlab::GitAccessWiki.new(actor, project, protocol, authentication_abilities: ssh_authentication_abilities) else - Gitlab::GitAccess.new(actor, project, protocol, authentication_abilities: ssh_authentication_abilities) + Gitlab::GitAccess.new(actor, + project, + protocol, + authentication_abilities: ssh_authentication_abilities, + env: parse_allowed_environment_variables) end access_status = access.check(params[:action], params[:changes]) diff --git a/lib/gitlab/checks/change_access.rb b/lib/gitlab/checks/change_access.rb index cb1065223d4..3d203017d9f 100644 --- a/lib/gitlab/checks/change_access.rb +++ b/lib/gitlab/checks/change_access.rb @@ -3,11 +3,12 @@ module Gitlab class ChangeAccess attr_reader :user_access, :project - def initialize(change, user_access:, project:) + def initialize(change, user_access:, project:, env: {}) @oldrev, @newrev, @ref = change.values_at(:oldrev, :newrev, :ref) @branch_name = Gitlab::Git.branch_name(@ref) @user_access = user_access @project = project + @env = env end def exec @@ -68,7 +69,7 @@ module Gitlab end def forced_push? - Gitlab::Checks::ForcePush.force_push?(@project, @oldrev, @newrev) + Gitlab::Checks::ForcePush.force_push?(@project, @oldrev, @newrev, env: @env) end def matching_merge_request? diff --git a/lib/gitlab/checks/force_push.rb b/lib/gitlab/checks/force_push.rb index 5fe86553bd0..589525e40ad 100644 --- a/lib/gitlab/checks/force_push.rb +++ b/lib/gitlab/checks/force_push.rb @@ -1,14 +1,14 @@ module Gitlab module Checks class ForcePush - def self.force_push?(project, oldrev, newrev) + def self.force_push?(project, oldrev, newrev, env: {}) return false if project.empty_repo? # Created or deleted branch if Gitlab::Git.blank_ref?(oldrev) || Gitlab::Git.blank_ref?(newrev) false else - missed_ref, _ = Gitlab::Popen.popen(%W(#{Gitlab.config.git.bin_path} --git-dir=#{project.repository.path_to_repo} rev-list --max-count=1 #{oldrev} ^#{newrev})) + missed_ref, _ = Gitlab::Git::RevList.new(oldrev, newrev, project: project, env: env).execute missed_ref.present? end end diff --git a/lib/gitlab/git/rev_list.rb b/lib/gitlab/git/rev_list.rb new file mode 100644 index 00000000000..ecdb7f07744 --- /dev/null +++ b/lib/gitlab/git/rev_list.rb @@ -0,0 +1,28 @@ +# Call out to the `git rev-list` command + +module Gitlab + module Git + class RevList + def initialize(oldrev, newrev, project:, env: nil) + @args = [Gitlab.config.git.bin_path, + "--git-dir=#{project.repository.path_to_repo}", + "rev-list", + "--max-count=1", + oldrev, + "^#{newrev}"] + + @env = env.slice(*allowed_environment_variables) + end + + def execute + Gitlab::Popen.popen(@args, nil, @env.slice(*allowed_environment_variables)) + end + + private + + def allowed_environment_variables + %w(GIT_ALTERNATE_OBJECT_DIRECTORIES GIT_OBJECT_DIRECTORY) + end + end + end +end diff --git a/lib/gitlab/git_access.rb b/lib/gitlab/git_access.rb index db07b7c5fcc..c6b6efda360 100644 --- a/lib/gitlab/git_access.rb +++ b/lib/gitlab/git_access.rb @@ -17,12 +17,13 @@ module Gitlab attr_reader :actor, :project, :protocol, :user_access, :authentication_abilities - def initialize(actor, project, protocol, authentication_abilities:) + def initialize(actor, project, protocol, authentication_abilities:, env: {}) @actor = actor @project = project @protocol = protocol @authentication_abilities = authentication_abilities @user_access = UserAccess.new(user, project: project) + @env = env end def check(cmd, changes) @@ -103,7 +104,7 @@ module Gitlab end def change_access_check(change) - Checks::ChangeAccess.new(change, user_access: user_access, project: project).exec + Checks::ChangeAccess.new(change, user_access: user_access, project: project, env: @env).exec end def protocol_allowed? diff --git a/lib/gitlab/popen.rb b/lib/gitlab/popen.rb index cc74bb29087..4bc5cda8cb5 100644 --- a/lib/gitlab/popen.rb +++ b/lib/gitlab/popen.rb @@ -5,13 +5,13 @@ module Gitlab module Popen extend self - def popen(cmd, path = nil) + def popen(cmd, path = nil, vars = {}) unless cmd.is_a?(Array) raise "System commands must be given as an array of strings" end path ||= Dir.pwd - vars = { "PWD" => path } + vars['PWD'] = path options = { chdir: path } unless File.directory?(path)