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Code Issues Releases Wiki Activity

Merge pull request #3824 from ThomasWaldmann/finding-pieces

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some more debug commands
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TW 2018-08-09 07:27:54 +02:00 committed by GitHub
commit 64f2fc0a65
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3 changed files with 137 additions and 8 deletions
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126
src/borg/archiver.py
View file

@ -74,7 +74,7 @@
from .item import Item
from .platform import get_flags, get_process_id, SyncFile
from .remote import RepositoryServer, RemoteRepository, cache_if_remote
from .repository import Repository, LIST_SCAN_LIMIT
from .repository import Repository, LIST_SCAN_LIMIT, TAG_PUT, TAG_DELETE, TAG_COMMIT
from .selftest import selftest
from .upgrader import AtticRepositoryUpgrader, BorgRepositoryUpgrader
@ -1930,7 +1930,85 @@ def do_debug_dump_manifest(self, args, repository, manifest, key):
@with_repository(manifest=False)
def do_debug_dump_repo_objs(self, args, repository):
"""dump (decrypted, decompressed) repo objects"""
"""dump (decrypted, decompressed) repo objects, repo index MUST be current/correct"""
from .crypto.key import key_factory
def decrypt_dump(i, id, cdata, tag=None, segment=None, offset=None):
if cdata is not None:
give_id = id if id != Manifest.MANIFEST_ID else None
data = key.decrypt(give_id, cdata)
else:
data = b''
tag_str = '' if tag is None else '_' + tag
segment_str = '_' + str(segment) if segment is not None else ''
offset_str = '_' + str(offset) if offset is not None else ''
id_str = '_' + bin_to_hex(id) if id is not None else ''
filename = '%08d%s%s%s%s.obj' % (i, segment_str, offset_str, tag_str, id_str)
print('Dumping', filename)
with open(filename, 'wb') as fd:
fd.write(data)
if args.ghost:
# dump ghosty stuff from segment files: not yet committed objects, deleted / superceded objects, commit tags
# set up the key without depending on a manifest obj
for id, cdata, tag, segment, offset in repository.scan_low_level():
if tag == TAG_PUT:
key = key_factory(repository, cdata)
break
i = 0
for id, cdata, tag, segment, offset in repository.scan_low_level():
if tag == TAG_PUT:
decrypt_dump(i, id, cdata, tag='put', segment=segment, offset=offset)
elif tag == TAG_DELETE:
decrypt_dump(i, id, None, tag='del', segment=segment, offset=offset)
elif tag == TAG_COMMIT:
decrypt_dump(i, None, None, tag='commit', segment=segment, offset=offset)
i += 1
else:
# set up the key without depending on a manifest obj
ids = repository.list(limit=1, marker=None)
cdata = repository.get(ids[0])
key = key_factory(repository, cdata)
marker = None
i = 0
while True:
result = repository.scan(limit=LIST_SCAN_LIMIT, marker=marker) # must use on-disk order scanning here
if not result:
break
marker = result[-1]
for id in result:
cdata = repository.get(id)
decrypt_dump(i, id, cdata)
i += 1
print('Done.')
return EXIT_SUCCESS
@with_repository(manifest=False)
def do_debug_search_repo_objs(self, args, repository):
"""search for byte sequences in repo objects, repo index MUST be current/correct"""
context = 32
def print_finding(info, wanted, data, offset):
before = data[offset - context:offset]
after = data[offset + len(wanted):offset + len(wanted) + context]
print('%s: %s %s %s == %r %r %r' % (info, before.hex(), wanted.hex(), after.hex(),
before, wanted, after))
wanted = args.wanted
try:
if wanted.startswith('hex:'):
wanted = unhexlify(wanted[4:])
elif wanted.startswith('str:'):
wanted = wanted[4:].encode('utf-8')
else:
raise ValueError('unsupported search term')
except (ValueError, UnicodeEncodeError):
wanted = None
if not wanted:
self.print_error('search term needs to be hex:123abc or str:foobar style')
return EXIT_ERROR
from .crypto.key import key_factory
# set up the key without depending on a manifest obj
ids = repository.list(limit=1, marker=None)
@ -1938,9 +2016,11 @@ def do_debug_dump_repo_objs(self, args, repository):
key = key_factory(repository, cdata)
marker = None
last_data = b''
last_id = None
i = 0
while True:
result = repository.list(limit=LIST_SCAN_LIMIT, marker=marker)
result = repository.scan(limit=LIST_SCAN_LIMIT, marker=marker) # must use on-disk order scanning here
if not result:
break
marker = result[-1]
@ -1948,11 +2028,26 @@ def do_debug_dump_repo_objs(self, args, repository):
cdata = repository.get(id)
give_id = id if id != Manifest.MANIFEST_ID else None
data = key.decrypt(give_id, cdata)
filename = '%06d_%s.obj' % (i, bin_to_hex(id))
print('Dumping', filename)
with open(filename, 'wb') as fd:
fd.write(data)
# try to locate wanted sequence crossing the border of last_data and data
boundary_data = last_data[-(len(wanted) - 1):] + data[:len(wanted) - 1]
if wanted in boundary_data:
boundary_data = last_data[-(len(wanted) - 1 + context):] + data[:len(wanted) - 1 + context]
offset = boundary_data.find(wanted)
info = '%d %s | %s' % (i, last_id.hex(), id.hex())
print_finding(info, wanted, boundary_data, offset)
# try to locate wanted sequence in data
count = data.count(wanted)
if count:
offset = data.find(wanted) # only determine first occurance's offset
info = "%d %s #%d" % (i, id.hex(), count)
print_finding(info, wanted, data, offset)
last_id, last_data = id, data
i += 1
if i % 10000 == 0:
print('%d objects processed.' % i)
print('Done.')
return EXIT_SUCCESS
@ -3995,6 +4090,23 @@ def define_archive_filters_group(subparser, *, sort_by=True, first_last=True):
subparser.add_argument('location', metavar='REPOSITORY',
type=location_validator(archive=False),
help='repo to dump')
subparser.add_argument('--ghost', dest='ghost', action='store_true',
help='dump all segment file contents, including deleted/uncommitted objects and commits.')
debug_search_repo_objs_epilog = process_epilog("""
This command searches raw (but decrypted and decompressed) repo objects for a specific bytes sequence.
""")
subparser = debug_parsers.add_parser('search-repo-objs', parents=[common_parser], add_help=False,
description=self.do_debug_search_repo_objs.__doc__,
epilog=debug_search_repo_objs_epilog,
formatter_class=argparse.RawDescriptionHelpFormatter,
help='search repo objects (debug)')
subparser.set_defaults(func=self.do_debug_search_repo_objs)
subparser.add_argument('location', metavar='REPOSITORY',
type=location_validator(archive=False),
help='repo to search')
subparser.add_argument('wanted', metavar='WANTED', type=str,
help='term to search the repo for, either 0x1234abcd hex term or a string')
debug_get_obj_epilog = process_epilog("""
This command gets an object from the repository.

17
src/borg/repository.py
View file

@ -962,6 +962,23 @@ def report_error(msg):
logger.info('Completed repository check, no problems found.')
return not error_found or repair
def scan_low_level(self):
"""Very low level scan over all segment file entries.
It does NOT care about what's committed and what not.
It does NOT care whether an object might be deleted or superceded later.
It just yields anything it finds in the segment files.
This is intended as a last-resort way to get access to all repo contents of damaged repos,
when there is uncommitted, but valuable data in there...
"""
for segment, filename in self.io.segment_iterator():
try:
for tag, key, offset, data in self.io.iter_objects(segment, include_data=True):
yield key, data, tag, segment, offset
except IntegrityError as err:
logger.error('Segment %d (%s) has IntegrityError(s) [%s] - skipping.' % (segment, filename, str(err)))
def _rollback(self, *, cleanup):
"""
"""

2
src/borg/testsuite/archiver.py
View file

@ -2335,7 +2335,7 @@ def test_debug_dump_repo_objs(self):
with changedir('output'):
output = self.cmd('debug', 'dump-repo-objs', self.repository_location)
output_dir = sorted(os.listdir('output'))
assert len(output_dir) > 0 and output_dir[0].startswith('000000_')
assert len(output_dir) > 0 and output_dir[0].startswith('00000000_')
assert 'Done.' in output
def test_debug_put_get_delete_obj(self):