Use python instead of slow shell script on verify-commits

This commit is contained in:
Chun Kuan Lee 2018-05-10 16:22:58 +00:00
parent e24bf1ce18
commit e5b2cd8e75
7 changed files with 169 additions and 161 deletions

View File

@ -104,5 +104,5 @@ jobs:
- test/lint/lint-all.sh
- if [ "$TRAVIS_REPO_SLUG" = "bitcoin/bitcoin" -a "$TRAVIS_EVENT_TYPE" = "cron" ]; then
while read LINE; do travis_retry gpg --keyserver hkp://subset.pool.sks-keyservers.net --recv-keys $LINE; done < contrib/verify-commits/trusted-keys &&
travis_wait 30 contrib/verify-commits/verify-commits.sh;
travis_wait 30 contrib/verify-commits/verify-commits.py;
fi

View File

@ -7,18 +7,18 @@ are PGP signed (nearly always merge commits), as well as a script to verify
commits against a trusted keys list.
Using verify-commits.sh safely
Using verify-commits.py safely
------------------------------
Remember that you can't use an untrusted script to verify itself. This means
that checking out code, then running `verify-commits.sh` against `HEAD` is
_not_ safe, because the version of `verify-commits.sh` that you just ran could
that checking out code, then running `verify-commits.py` against `HEAD` is
_not_ safe, because the version of `verify-commits.py` that you just ran could
be backdoored. Instead, you need to use a trusted version of verify-commits
prior to checkout to make sure you're checking out only code signed by trusted
keys:
git fetch origin && \
./contrib/verify-commits/verify-commits.sh origin/master && \
./contrib/verify-commits/verify-commits.py origin/master && \
git checkout origin/master
Note that the above isn't a good UI/UX yet, and needs significant improvements
@ -42,6 +42,6 @@ said key. In order to avoid bumping the root-of-trust `trusted-git-root`
file, individual commits which were signed by such a key can be added to the
`allow-revsig-commits` file. That way, the PGP signatures are still verified
but no new commits can be signed by any expired/revoked key. To easily build a
list of commits which need to be added, verify-commits.sh can be edited to test
list of commits which need to be added, verify-commits.py can be edited to test
each commit with BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG set to both 1 and 0, and
those which need it set to 1 printed.

View File

@ -0,0 +1,2 @@
f8feaa4636260b599294c7285bcf1c8b7737f74e
8040ae6fc576e9504186f2ae3ff2c8125de1095c

View File

@ -0,0 +1,4 @@
6052d509105790a26b3ad5df43dd61e7f1b24a12
3798e5de334c3deb5f71302b782f6b8fbd5087f1
326ffed09bfcc209a2efd6a2ebc69edf6bd200b5
97d83739db0631be5d4ba86af3616014652c00ec

View File

@ -12,9 +12,9 @@ while read LINE; do
if [ "$4" != "refs/heads/master" ]; then
continue
fi
if ! ./contrib/verify-commits/verify-commits.sh $3 > /dev/null 2>&1; then
if ! ./contrib/verify-commits/verify-commits.py $3 > /dev/null 2>&1; then
echo "ERROR: A commit is not signed, can't push"
./contrib/verify-commits/verify-commits.sh
./contrib/verify-commits/verify-commits.py
exit 1
fi
done < /dev/stdin

View File

@ -0,0 +1,155 @@
#!/usr/bin/env python3
# Copyright (c) 2018 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Verify commits against a trusted keys list."""
import argparse
import hashlib
import os
import subprocess
import sys
import time
GIT = os.getenv('GIT', 'git')
def tree_sha512sum(commit='HEAD'):
"""Calculate the Tree-sha512 for the commit.
This is copied from github-merge.py."""
# request metadata for entire tree, recursively
files = []
blob_by_name = {}
for line in subprocess.check_output([GIT, 'ls-tree', '--full-tree', '-r', commit]).splitlines():
name_sep = line.index(b'\t')
metadata = line[:name_sep].split() # perms, 'blob', blobid
assert metadata[1] == b'blob'
name = line[name_sep + 1:]
files.append(name)
blob_by_name[name] = metadata[2]
files.sort()
# open connection to git-cat-file in batch mode to request data for all blobs
# this is much faster than launching it per file
p = subprocess.Popen([GIT, 'cat-file', '--batch'], stdout=subprocess.PIPE, stdin=subprocess.PIPE)
overall = hashlib.sha512()
for f in files:
blob = blob_by_name[f]
# request blob
p.stdin.write(blob + b'\n')
p.stdin.flush()
# read header: blob, "blob", size
reply = p.stdout.readline().split()
assert reply[0] == blob and reply[1] == b'blob'
size = int(reply[2])
# hash the blob data
intern = hashlib.sha512()
ptr = 0
while ptr < size:
bs = min(65536, size - ptr)
piece = p.stdout.read(bs)
if len(piece) == bs:
intern.update(piece)
else:
raise IOError('Premature EOF reading git cat-file output')
ptr += bs
dig = intern.hexdigest()
assert p.stdout.read(1) == b'\n' # ignore LF that follows blob data
# update overall hash with file hash
overall.update(dig.encode("utf-8"))
overall.update(" ".encode("utf-8"))
overall.update(f)
overall.update("\n".encode("utf-8"))
p.stdin.close()
if p.wait():
raise IOError('Non-zero return value executing git cat-file')
return overall.hexdigest()
def main():
# Parse arguments
parser = argparse.ArgumentParser(usage='%(prog)s [options] [commit id]')
parser.add_argument('--disable-tree-check', action='store_false', dest='verify_tree', help='disable SHA-512 tree check')
parser.add_argument('--clean-merge', type=float, dest='clean_merge', default=float('inf'), help='Only check clean merge after <NUMBER> days ago (default: %(default)s)', metavar='NUMBER')
parser.add_argument('commit', nargs='?', default='HEAD', help='Check clean merge up to commit <commit>')
args = parser.parse_args()
# get directory of this program and read data files
dirname = os.path.dirname(os.path.abspath(__file__))
print("Using verify-commits data from " + dirname)
verified_root = open(dirname + "/trusted-git-root", "r").read().splitlines()[0]
verified_sha512_root = open(dirname + "/trusted-sha512-root-commit", "r").read().splitlines()[0]
revsig_allowed = open(dirname + "/allow-revsig-commits", "r").read().splitlines()
unclean_merge_allowed = open(dirname + "/allow-unclean-merge-commits", "r").read().splitlines()
incorrect_sha512_allowed = open(dirname + "/allow-incorrect-sha512-commits", "r").read().splitlines()
# Set commit and branch and set variables
current_commit = args.commit
if ' ' in current_commit:
print("Commit must not contain spaces", file=sys.stderr)
sys.exit(1)
verify_tree = args.verify_tree
no_sha1 = True
prev_commit = ""
initial_commit = current_commit
branch = subprocess.check_output([GIT, 'show', '-s', '--format=%H', initial_commit], universal_newlines=True).splitlines()[0]
# Iterate through commits
while True:
if current_commit == verified_root:
print('There is a valid path from "{}" to {} where all commits are signed!'.format(initial_commit, verified_root))
sys.exit(0)
if current_commit == verified_sha512_root:
if verify_tree:
print("All Tree-SHA512s matched up to {}".format(verified_sha512_root), file=sys.stderr)
verify_tree = False
no_sha1 = False
os.environ['BITCOIN_VERIFY_COMMITS_ALLOW_SHA1'] = "0" if no_sha1 else "1"
os.environ['BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG'] = "1" if current_commit in revsig_allowed else "0"
# Check that the commit (and parents) was signed with a trusted key
if subprocess.call([GIT, '-c', 'gpg.program={}/gpg.sh'.format(dirname), 'verify-commit', current_commit], stdout=subprocess.DEVNULL):
if prev_commit != "":
print("No parent of {} was signed with a trusted key!".format(prev_commit), file=sys.stderr)
print("Parents are:", file=sys.stderr)
parents = subprocess.check_output([GIT, 'show', '-s', '--format=format:%P', prev_commit], universal_newlines=True).splitlines()[0].split(' ')
for parent in parents:
subprocess.call([GIT, 'show', '-s', parent], stdout=sys.stderr)
else:
print("{} was not signed with a trusted key!".format(current_commit), file=sys.stderr)
sys.exit(1)
# Check the Tree-SHA512
if (verify_tree or prev_commit == "") and current_commit not in incorrect_sha512_allowed:
tree_hash = tree_sha512sum(current_commit)
if ("Tree-SHA512: {}".format(tree_hash)) not in subprocess.check_output([GIT, 'show', '-s', '--format=format:%B', current_commit], universal_newlines=True).splitlines():
print("Tree-SHA512 did not match for commit " + current_commit, file=sys.stderr)
sys.exit(1)
# Merge commits should only have two parents
parents = subprocess.check_output([GIT, 'show', '-s', '--format=format:%P', current_commit], universal_newlines=True).splitlines()[0].split(' ')
if len(parents) > 2:
print("Commit {} is an octopus merge".format(current_commit), file=sys.stderr)
sys.exit(1)
# Check that the merge commit is clean
commit_time = int(subprocess.check_output([GIT, 'show', '-s', '--format=format:%ct', current_commit], universal_newlines=True).splitlines()[0])
check_merge = commit_time > time.time() - args.clean_merge * 24 * 60 * 60 # Only check commits in clean_merge days
allow_unclean = current_commit in unclean_merge_allowed
if len(parents) == 2 and check_merge and not allow_unclean:
current_tree = subprocess.check_output([GIT, 'show', '--format=%T', current_commit], universal_newlines=True).splitlines()[0]
subprocess.call([GIT, 'checkout', '--force', '--quiet', parents[0]])
subprocess.call([GIT, 'merge', '--no-ff', '--quiet', parents[1]], stdout=subprocess.DEVNULL)
recreated_tree = subprocess.check_output([GIT, 'show', '--format=format:%T', 'HEAD'], universal_newlines=True).splitlines()[0]
if current_tree != recreated_tree:
print("Merge commit {} is not clean".format(current_commit), file=sys.stderr)
subprocess.call([GIT, 'diff', current_commit])
subprocess.call([GIT, 'checkout', '--force', '--quiet', branch])
sys.exit(1)
subprocess.call([GIT, 'checkout', '--force', '--quiet', branch])
prev_commit = current_commit
current_commit = parents[0]
if __name__ == '__main__':
main()

View File

@ -1,153 +0,0 @@
#!/bin/sh
# Copyright (c) 2014-2016 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
DIR=$(dirname "$0")
[ "/${DIR#/}" != "$DIR" ] && DIR=$(dirname "$(pwd)/$0")
echo "Using verify-commits data from ${DIR}"
VERIFIED_ROOT=$(cat "${DIR}/trusted-git-root")
VERIFIED_SHA512_ROOT=$(cat "${DIR}/trusted-sha512-root-commit")
REVSIG_ALLOWED=$(cat "${DIR}/allow-revsig-commits")
HAVE_GNU_SHA512=1
[ ! -x "$(which sha512sum)" ] && HAVE_GNU_SHA512=0
if [ x"$1" = "x" ]; then
CURRENT_COMMIT="HEAD"
else
CURRENT_COMMIT="$1"
fi
if [ "${CURRENT_COMMIT#* }" != "$CURRENT_COMMIT" ]; then
echo "Commit must not contain spaces?" > /dev/stderr
exit 1
fi
VERIFY_TREE=0
if [ x"$2" = "x--tree-checks" ]; then
VERIFY_TREE=1
fi
NO_SHA1=1
PREV_COMMIT=""
INITIAL_COMMIT="${CURRENT_COMMIT}"
BRANCH="$(git rev-parse --abbrev-ref HEAD)"
while true; do
if [ "$CURRENT_COMMIT" = $VERIFIED_ROOT ]; then
echo "There is a valid path from \"$INITIAL_COMMIT\" to $VERIFIED_ROOT where all commits are signed!"
exit 0
fi
if [ "$CURRENT_COMMIT" = $VERIFIED_SHA512_ROOT ]; then
if [ "$VERIFY_TREE" = "1" ]; then
echo "All Tree-SHA512s matched up to $VERIFIED_SHA512_ROOT" > /dev/stderr
fi
VERIFY_TREE=0
NO_SHA1=0
fi
if [ "$NO_SHA1" = "1" ]; then
export BITCOIN_VERIFY_COMMITS_ALLOW_SHA1=0
else
export BITCOIN_VERIFY_COMMITS_ALLOW_SHA1=1
fi
if [ "${REVSIG_ALLOWED#*$CURRENT_COMMIT}" != "$REVSIG_ALLOWED" ]; then
export BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG=1
else
export BITCOIN_VERIFY_COMMITS_ALLOW_REVSIG=0
fi
if ! git -c "gpg.program=${DIR}/gpg.sh" verify-commit "$CURRENT_COMMIT" > /dev/null; then
if [ "$PREV_COMMIT" != "" ]; then
echo "No parent of $PREV_COMMIT was signed with a trusted key!" > /dev/stderr
echo "Parents are:" > /dev/stderr
PARENTS=$(git show -s --format=format:%P $PREV_COMMIT)
for PARENT in $PARENTS; do
git show -s $PARENT > /dev/stderr
done
else
echo "$CURRENT_COMMIT was not signed with a trusted key!" > /dev/stderr
fi
exit 1
fi
# We always verify the top of the tree
if [ "$VERIFY_TREE" = 1 -o "$PREV_COMMIT" = "" ]; then
IFS_CACHE="$IFS"
IFS='
'
for LINE in $(git ls-tree --full-tree -r "$CURRENT_COMMIT"); do
case "$LINE" in
"12"*)
echo "Repo contains symlinks" > /dev/stderr
IFS="$IFS_CACHE"
exit 1
;;
esac
done
IFS="$IFS_CACHE"
FILE_HASHES=""
for FILE in $(git ls-tree --full-tree -r --name-only "$CURRENT_COMMIT" | LC_ALL=C sort); do
if [ "$HAVE_GNU_SHA512" = 1 ]; then
HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | sha512sum | { read FIRST _; echo $FIRST; } )
else
HASH=$(git cat-file blob "$CURRENT_COMMIT":"$FILE" | shasum -a 512 | { read FIRST _; echo $FIRST; } )
fi
[ "$FILE_HASHES" != "" ] && FILE_HASHES="$FILE_HASHES"'
'
FILE_HASHES="$FILE_HASHES$HASH $FILE"
done
if [ "$HAVE_GNU_SHA512" = 1 ]; then
TREE_HASH="$(echo "$FILE_HASHES" | sha512sum)"
else
TREE_HASH="$(echo "$FILE_HASHES" | shasum -a 512)"
fi
HASH_MATCHES=0
MSG="$(git show -s --format=format:%B "$CURRENT_COMMIT" | tail -n1)"
case "$MSG -" in
"Tree-SHA512: $TREE_HASH")
HASH_MATCHES=1;;
esac
if [ "$HASH_MATCHES" = "0" ]; then
echo "Tree-SHA512 did not match for commit $CURRENT_COMMIT" > /dev/stderr
exit 1
fi
fi
PARENTS=$(git show -s --format=format:%P "$CURRENT_COMMIT")
PARENT1=${PARENTS%% *}
PARENT2=""
if [ "x$PARENT1" != "x$PARENTS" ]; then
PARENTX=${PARENTS#* }
PARENT2=${PARENTX%% *}
if [ "x$PARENT2" != "x$PARENTX" ]; then
echo "Commit $CURRENT_COMMIT is an octopus merge" > /dev/stderr
exit 1
fi
fi
if [ "x$PARENT2" != "x" ]; then
CURRENT_TREE="$(git show --format="%T" "$CURRENT_COMMIT")"
git checkout --force --quiet "$PARENT1"
git merge --no-ff --quiet "$PARENT2" >/dev/null
RECREATED_TREE="$(git show --format="%T" HEAD)"
if [ "$CURRENT_TREE" != "$RECREATED_TREE" ]; then
echo "Merge commit $CURRENT_COMMIT is not clean" > /dev/stderr
git diff "$CURRENT_COMMIT"
git checkout --force --quiet "$BRANCH"
exit 1
fi
git checkout --force --quiet "$BRANCH"
fi
PREV_COMMIT="$CURRENT_COMMIT"
CURRENT_COMMIT="$PARENT1"
done