element-web/scripts/deploy.py
Michael Telatynski 7defcf3957
Adding tarfile member sanitization to extractall() (#23906)
Co-authored-by: Šimon Brandner <simon.bra.ag@gmail.com>
Co-authored-by: TrellixVulnTeam <charles.mcfarland@trellix.com>
2022-12-05 17:03:17 +00:00

242 lines
8.3 KiB
Python
Executable file

#!/usr/bin/env python3
#
# download and unpack a element-web tarball.
#
# Allows `bundles` to be extracted to a common directory, and a link to
# config.json to be added.
import argparse
import errno
import os
import os.path
import subprocess
import sys
import tarfile
import shutil
import glob
from urllib.request import urlretrieve
class DeployException(Exception):
pass
def create_relative_symlink(linkname, target):
relpath = os.path.relpath(target, os.path.dirname(linkname))
print("Symlink %s -> %s" % (linkname, relpath))
try:
os.symlink(relpath, linkname)
except OSError as e:
if e.errno == errno.EEXIST:
# atomic modification
os.symlink(relpath, linkname + ".tmp")
os.rename(linkname + ".tmp", linkname)
else:
raise e
def move_bundles(source, dest):
"""Move the contents of the 'bundles' directory to a common dir
We check that we will not be overwriting anything before we proceed.
Args:
source (str): path to 'bundles' within the extracted tarball
dest (str): target common directory
"""
if not os.path.isdir(dest):
os.mkdir(dest)
# build a map from source to destination, checking for non-existence as we go.
renames = {}
for f in os.listdir(source):
dst = os.path.join(dest, f)
if os.path.exists(dst):
print(
"Skipping bundle. The bundle includes '%s' which we have previously deployed."
% f
)
else:
renames[os.path.join(source, f)] = dst
for (src, dst) in renames.items():
print("Move %s -> %s" % (src, dst))
os.rename(src, dst)
class Deployer:
def __init__(self):
self.packages_path = "."
self.bundles_path = None
self.should_clean = False
self.symlink_latest = None
# filename -> symlink path e.g 'config.localhost.json' => '../localhost/config.json'
self.symlink_paths = {}
self.verify_signature = True
def fetch(self, tarball, extract_path):
"""Download a tarball, verifies it if needed, and unpacks it
Returns:
(str) the path to the unpacked directory
"""
print("Fetching %s to %s" % (tarball, extract_path))
name_str = os.path.basename(tarball).replace(".tar.gz", "")
extracted_dir = os.path.join(extract_path, name_str)
if os.path.exists(extracted_dir):
raise DeployException('Cannot unpack %s: %s already exists' % (
tarball, extracted_dir))
downloaded = False
if tarball.startswith("http://") or tarball.startswith("https://"):
tarball = self.download_and_verify(tarball)
print("Downloaded file: %s" % tarball)
downloaded = True
try:
with tarfile.open(tarball) as tar:
def is_within_directory(directory, target):
abs_directory = os.path.abspath(directory)
abs_target = os.path.abspath(target)
prefix = os.path.commonprefix([abs_directory, abs_target])
return prefix == abs_directory
def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
for member in tar.getmembers():
member_path = os.path.join(path, member.name)
if not is_within_directory(path, member_path):
raise Exception("Attempted Path Traversal in Tar File")
tar.extractall(path, members, numeric_owner=numeric_owner)
safe_extract(tar, extract_path)
finally:
if self.should_clean and downloaded:
os.remove(tarball)
print("Extracted into: %s" % extracted_dir)
return extracted_dir
def deploy(self, extracted_dir):
"""Applies symlinks and handles the bundles directory on an extracted tarball"""
print("Deploying %s" % extracted_dir)
if self.symlink_paths:
for link_path, file_path in self.symlink_paths.items():
create_relative_symlink(
target=file_path,
linkname=os.path.join(extracted_dir, link_path)
)
if self.bundles_path:
extracted_bundles = os.path.join(extracted_dir, 'bundles')
move_bundles(source=extracted_bundles, dest=self.bundles_path)
# replace the extracted_bundles dir (which may not be empty if some
# bundles were skipped) with a symlink to the common dir.
shutil.rmtree(extracted_bundles)
create_relative_symlink(
target=self.bundles_path,
linkname=extracted_bundles,
)
if self.symlink_latest:
create_relative_symlink(
target=extracted_dir,
linkname=self.symlink_latest,
)
def download_and_verify(self, url):
tarball = self.download_file(url)
if self.verify_signature:
sigfile = self.download_file(url + ".asc")
subprocess.check_call(["gpg", "--verify", sigfile, tarball])
return tarball
def download_file(self, url):
if not os.path.isdir(self.packages_path):
os.mkdir(self.packages_path)
local_filename = os.path.join(self.packages_path,
url.split('/')[-1])
sys.stdout.write("Downloading %s -> %s..." % (url, local_filename))
sys.stdout.flush()
urlretrieve(url, local_filename)
print ("Done")
return local_filename
if __name__ == "__main__":
parser = argparse.ArgumentParser("Deploy a Riot build on a web server.")
parser.add_argument(
"-p", "--packages-dir", default="./packages", help=(
"The directory to download the tarball into. (Default: '%(default)s')"
)
)
parser.add_argument(
"-e", "--extract-path", default="./deploys", help=(
"The location to extract .tar.gz files to. (Default: '%(default)s')"
)
)
parser.add_argument(
"-b", "--bundles-dir", nargs='?', default="./bundles", help=(
"A directory to move the contents of the 'bundles' directory to. A \
symlink to the bundles directory will also be written inside the \
extracted tarball. Example: './bundles'. \
(Default: '%(default)s')"
)
)
parser.add_argument(
"-c", "--clean", action="store_true", default=False, help=(
"Remove .tar.gz files after they have been downloaded and extracted. \
(Default: %(default)s)"
)
)
parser.add_argument(
"--include", nargs='*', default=['./config*.json'], help=(
"Symlink these files into the root of the deployed tarball. \
Useful for config files and home pages. Supports glob syntax. \
(Default: '%(default)s')"
)
)
parser.add_argument(
"-s", "--symlink", dest="symlink", default="./latest", help=(
"Write a symlink to this location pointing to the extracted tarball. \
New builds will keep overwriting this symlink. The symlink will point \
to the webapp directory INSIDE the tarball."
)
)
parser.add_argument(
"target", help=(
"filename of extracted directory, tarball, or URL to download."
),
)
args = parser.parse_args()
deployer = Deployer()
deployer.packages_path = args.packages_dir
deployer.bundles_path = args.bundles_dir
deployer.should_clean = args.clean
deployer.symlink_latest = args.symlink
for include in args.include:
deployer.symlink_paths.update({ os.path.basename(pth): pth for pth in glob.iglob(include) })
if os.path.isdir(args.target):
# If the given directory contains a single directory then use that instead, the ci package wraps in an extra dir
files = os.listdir(args.target)
if len(files) == 1 and os.path.isdir(os.path.join(args.target, files[0])):
extracted_dir = os.path.join(args.target, files[0])
else:
extracted_dir = args.target
else:
extracted_dir = deployer.fetch(args.target, args.extract_path)
deployer.deploy(extracted_dir)