mirror of
https://github.com/borgbackup/borg.git
synced 2026-03-18 00:26:13 -04:00
eab9f5a07b
You can now control the files cache mode using this option:
--files-cache={ctime,mtime,size,inode,rechunk,disabled}*
(only some combinations are supported)
Previously, only these modes were supported:
- mtime,size,inode (default of borg < 1.1.0rc4)
- mtime,size (by using --ignore-inode)
- disabled (by using --no-files-cache)
Now, you additionally get:
- ctime alternatively to mtime (more safe), e.g.:
ctime,size,inode (this is the new default of borg >= 1.1.0rc4)
- rechunk (consider all files as changed, rechunk them)
Deprecated:
- --ignore-inodes (use modes without "inode")
- --no-files-cache (use "disabled" mode)
The tests needed some changes:
- previously, we use os.utime() to set a files mtime (atime) to specific
values, but that does not work for ctime.
- now use time.sleep() to create the "latest file" that usually does
not end up in the files cache (see FAQ)
(cherry picked from commit 5e2de8ba67)
1087 lines
50 KiB
Python
1087 lines
50 KiB
Python
import configparser
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import os
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import shutil
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import stat
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from binascii import unhexlify
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from collections import namedtuple
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from time import perf_counter
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import msgpack
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from .logger import create_logger
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logger = create_logger()
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from .constants import CACHE_README, DEFAULT_FILES_CACHE_MODE
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from .hashindex import ChunkIndex, ChunkIndexEntry, CacheSynchronizer
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from .helpers import Location
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from .helpers import Error
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from .helpers import Manifest
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from .helpers import get_cache_dir, get_security_dir
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from .helpers import int_to_bigint, bigint_to_int, bin_to_hex, parse_stringified_list
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from .helpers import format_file_size
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from .helpers import safe_ns
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from .helpers import yes, hostname_is_unique
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from .helpers import remove_surrogates
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from .helpers import ProgressIndicatorPercent, ProgressIndicatorMessage
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from .helpers import set_ec, EXIT_WARNING
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from .helpers import truncate_and_unlink
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from .item import ArchiveItem, ChunkListEntry
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from .crypto.key import PlaintextKey
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from .crypto.file_integrity import IntegrityCheckedFile, DetachedIntegrityCheckedFile, FileIntegrityError
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from .locking import Lock
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from .platform import SaveFile
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from .remote import cache_if_remote
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from .repository import LIST_SCAN_LIMIT
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# note: cmtime might me either a ctime or a mtime timestamp
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FileCacheEntry = namedtuple('FileCacheEntry', 'age inode size cmtime chunk_ids')
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class SecurityManager:
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"""
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Tracks repositories. Ensures that nothing bad happens (repository swaps,
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replay attacks, unknown repositories etc.).
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This is complicated by the Cache being initially used for this, while
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only some commands actually use the Cache, which meant that other commands
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did not perform these checks.
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Further complications were created by the Cache being a cache, so it
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could be legitimately deleted, which is annoying because Borg didn't
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recognize repositories after that.
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Therefore a second location, the security database (see get_security_dir),
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was introduced which stores this information. However, this means that
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the code has to deal with a cache existing but no security DB entry,
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or inconsistencies between the security DB and the cache which have to
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be reconciled, and also with no cache existing but a security DB entry.
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"""
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def __init__(self, repository):
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self.repository = repository
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self.dir = get_security_dir(repository.id_str)
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self.cache_dir = cache_dir(repository)
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self.key_type_file = os.path.join(self.dir, 'key-type')
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self.location_file = os.path.join(self.dir, 'location')
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self.manifest_ts_file = os.path.join(self.dir, 'manifest-timestamp')
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def known(self):
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return os.path.exists(self.key_type_file)
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def key_matches(self, key):
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if not self.known():
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return False
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try:
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with open(self.key_type_file, 'r') as fd:
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type = fd.read()
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return type == str(key.TYPE)
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except OSError as exc:
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logger.warning('Could not read/parse key type file: %s', exc)
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def save(self, manifest, key):
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logger.debug('security: saving state for %s to %s', self.repository.id_str, self.dir)
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current_location = self.repository._location.canonical_path()
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logger.debug('security: current location %s', current_location)
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logger.debug('security: key type %s', str(key.TYPE))
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logger.debug('security: manifest timestamp %s', manifest.timestamp)
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with open(self.location_file, 'w') as fd:
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fd.write(current_location)
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with open(self.key_type_file, 'w') as fd:
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fd.write(str(key.TYPE))
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with open(self.manifest_ts_file, 'w') as fd:
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fd.write(manifest.timestamp)
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def assert_location_matches(self, cache_config=None):
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# Warn user before sending data to a relocated repository
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try:
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with open(self.location_file) as fd:
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previous_location = fd.read()
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logger.debug('security: read previous location %r', previous_location)
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except FileNotFoundError:
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logger.debug('security: previous location file %s not found', self.location_file)
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previous_location = None
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except OSError as exc:
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logger.warning('Could not read previous location file: %s', exc)
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previous_location = None
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if cache_config and cache_config.previous_location and previous_location != cache_config.previous_location:
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# Reconcile cache and security dir; we take the cache location.
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previous_location = cache_config.previous_location
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logger.debug('security: using previous_location of cache: %r', previous_location)
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repository_location = self.repository._location.canonical_path()
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if previous_location and previous_location != repository_location:
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msg = ("Warning: The repository at location {} was previously located at {}\n".format(
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repository_location, previous_location) +
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"Do you want to continue? [yN] ")
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if not yes(msg, false_msg="Aborting.", invalid_msg="Invalid answer, aborting.",
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retry=False, env_var_override='BORG_RELOCATED_REPO_ACCESS_IS_OK'):
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raise Cache.RepositoryAccessAborted()
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# adapt on-disk config immediately if the new location was accepted
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logger.debug('security: updating location stored in cache and security dir')
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with open(self.location_file, 'w') as fd:
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fd.write(repository_location)
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if cache_config:
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cache_config.save()
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def assert_no_manifest_replay(self, manifest, key, cache_config=None):
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try:
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with open(self.manifest_ts_file) as fd:
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timestamp = fd.read()
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logger.debug('security: read manifest timestamp %r', timestamp)
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except FileNotFoundError:
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logger.debug('security: manifest timestamp file %s not found', self.manifest_ts_file)
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timestamp = ''
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except OSError as exc:
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logger.warning('Could not read previous location file: %s', exc)
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timestamp = ''
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if cache_config:
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timestamp = max(timestamp, cache_config.timestamp or '')
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logger.debug('security: determined newest manifest timestamp as %s', timestamp)
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# If repository is older than the cache or security dir something fishy is going on
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if timestamp and timestamp > manifest.timestamp:
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if isinstance(key, PlaintextKey):
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raise Cache.RepositoryIDNotUnique()
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else:
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raise Cache.RepositoryReplay()
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def assert_key_type(self, key, cache_config=None):
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# Make sure an encrypted repository has not been swapped for an unencrypted repository
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if cache_config and cache_config.key_type is not None and cache_config.key_type != str(key.TYPE):
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raise Cache.EncryptionMethodMismatch()
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if self.known() and not self.key_matches(key):
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raise Cache.EncryptionMethodMismatch()
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def assert_secure(self, manifest, key, *, cache_config=None, warn_if_unencrypted=True):
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# warn_if_unencrypted=False is only used for initializing a new repository.
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# Thus, avoiding asking about a repository that's currently initializing.
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self.assert_access_unknown(warn_if_unencrypted, manifest, key)
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if cache_config:
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self._assert_secure(manifest, key, cache_config)
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else:
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cache_config = CacheConfig(self.repository)
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if cache_config.exists():
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with cache_config:
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self._assert_secure(manifest, key, cache_config)
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else:
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self._assert_secure(manifest, key)
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logger.debug('security: repository checks ok, allowing access')
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def _assert_secure(self, manifest, key, cache_config=None):
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self.assert_location_matches(cache_config)
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self.assert_key_type(key, cache_config)
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self.assert_no_manifest_replay(manifest, key, cache_config)
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if not self.known():
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logger.debug('security: remembering previously unknown repository')
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self.save(manifest, key)
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def assert_access_unknown(self, warn_if_unencrypted, manifest, key):
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# warn_if_unencrypted=False is only used for initializing a new repository.
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# Thus, avoiding asking about a repository that's currently initializing.
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if not key.logically_encrypted and not self.known():
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msg = ("Warning: Attempting to access a previously unknown unencrypted repository!\n" +
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"Do you want to continue? [yN] ")
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allow_access = not warn_if_unencrypted or yes(msg, false_msg="Aborting.",
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invalid_msg="Invalid answer, aborting.",
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retry=False, env_var_override='BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK')
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if allow_access:
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if warn_if_unencrypted:
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logger.debug('security: remembering unknown unencrypted repository (explicitly allowed)')
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else:
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logger.debug('security: initializing unencrypted repository')
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self.save(manifest, key)
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else:
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raise Cache.CacheInitAbortedError()
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def assert_secure(repository, manifest):
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sm = SecurityManager(repository)
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sm.assert_secure(manifest, manifest.key)
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def recanonicalize_relative_location(cache_location, repository):
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# borg < 1.0.8rc1 had different canonicalization for the repo location (see #1655 and #1741).
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repo_location = repository._location.canonical_path()
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rl = Location(repo_location)
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cl = Location(cache_location)
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if cl.proto == rl.proto and cl.user == rl.user and cl.host == rl.host and cl.port == rl.port \
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and \
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cl.path and rl.path and \
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cl.path.startswith('/~/') and rl.path.startswith('/./') and cl.path[3:] == rl.path[3:]:
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# everything is same except the expected change in relative path canonicalization,
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# update previous_location to avoid warning / user query about changed location:
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return repo_location
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else:
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return cache_location
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def cache_dir(repository, path=None):
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return path or os.path.join(get_cache_dir(), repository.id_str)
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class CacheConfig:
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def __init__(self, repository, path=None, lock_wait=None):
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self.repository = repository
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self.path = cache_dir(repository, path)
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self.config_path = os.path.join(self.path, 'config')
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self.lock = None
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self.lock_wait = lock_wait
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def __enter__(self):
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self.open()
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return self
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def __exit__(self, exc_type, exc_val, exc_tb):
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self.close()
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def exists(self):
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return os.path.exists(self.config_path)
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def create(self):
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assert not self.exists()
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config = configparser.ConfigParser(interpolation=None)
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config.add_section('cache')
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config.set('cache', 'version', '1')
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config.set('cache', 'repository', self.repository.id_str)
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config.set('cache', 'manifest', '')
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config.add_section('integrity')
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config.set('integrity', 'manifest', '')
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with SaveFile(self.config_path) as fd:
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config.write(fd)
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def open(self):
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self.lock = Lock(os.path.join(self.path, 'lock'), exclusive=True, timeout=self.lock_wait,
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kill_stale_locks=hostname_is_unique()).acquire()
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self.load()
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def load(self):
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self._config = configparser.ConfigParser(interpolation=None)
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self._config.read(self.config_path)
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self._check_upgrade(self.config_path)
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self.id = self._config.get('cache', 'repository')
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self.manifest_id = unhexlify(self._config.get('cache', 'manifest'))
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self.timestamp = self._config.get('cache', 'timestamp', fallback=None)
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self.key_type = self._config.get('cache', 'key_type', fallback=None)
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self.ignored_features = set(parse_stringified_list(self._config.get('cache', 'ignored_features', fallback='')))
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self.mandatory_features = set(parse_stringified_list(self._config.get('cache', 'mandatory_features', fallback='')))
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try:
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self.integrity = dict(self._config.items('integrity'))
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if self._config.get('cache', 'manifest') != self.integrity.pop('manifest'):
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# The cache config file is updated (parsed with ConfigParser, the state of the ConfigParser
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# is modified and then written out.), not re-created.
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# Thus, older versions will leave our [integrity] section alone, making the section's data invalid.
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# Therefore, we also add the manifest ID to this section and
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# can discern whether an older version interfered by comparing the manifest IDs of this section
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# and the main [cache] section.
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self.integrity = {}
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logger.warning('Cache integrity data not available: old Borg version modified the cache.')
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except configparser.NoSectionError:
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logger.debug('Cache integrity: No integrity data found (files, chunks). Cache is from old version.')
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self.integrity = {}
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previous_location = self._config.get('cache', 'previous_location', fallback=None)
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if previous_location:
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self.previous_location = recanonicalize_relative_location(previous_location, self.repository)
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else:
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self.previous_location = None
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def save(self, manifest=None, key=None):
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if manifest:
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self._config.set('cache', 'manifest', manifest.id_str)
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self._config.set('cache', 'timestamp', manifest.timestamp)
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self._config.set('cache', 'ignored_features', ','.join(self.ignored_features))
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self._config.set('cache', 'mandatory_features', ','.join(self.mandatory_features))
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if not self._config.has_section('integrity'):
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self._config.add_section('integrity')
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for file, integrity_data in self.integrity.items():
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self._config.set('integrity', file, integrity_data)
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self._config.set('integrity', 'manifest', manifest.id_str)
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if key:
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self._config.set('cache', 'key_type', str(key.TYPE))
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self._config.set('cache', 'previous_location', self.repository._location.canonical_path())
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with SaveFile(self.config_path) as fd:
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self._config.write(fd)
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def close(self):
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if self.lock is not None:
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self.lock.release()
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self.lock = None
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def _check_upgrade(self, config_path):
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try:
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cache_version = self._config.getint('cache', 'version')
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wanted_version = 1
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if cache_version != wanted_version:
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self.close()
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raise Exception('%s has unexpected cache version %d (wanted: %d).' %
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(config_path, cache_version, wanted_version))
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except configparser.NoSectionError:
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self.close()
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raise Exception('%s does not look like a Borg cache.' % config_path) from None
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class Cache:
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"""Client Side cache
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"""
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class RepositoryIDNotUnique(Error):
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"""Cache is newer than repository - do you have multiple, independently updated repos with same ID?"""
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class RepositoryReplay(Error):
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"""Cache is newer than repository - this is either an attack or unsafe (multiple repos with same ID)"""
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class CacheInitAbortedError(Error):
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"""Cache initialization aborted"""
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class RepositoryAccessAborted(Error):
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"""Repository access aborted"""
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class EncryptionMethodMismatch(Error):
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"""Repository encryption method changed since last access, refusing to continue"""
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@staticmethod
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def break_lock(repository, path=None):
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path = cache_dir(repository, path)
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Lock(os.path.join(path, 'lock'), exclusive=True).break_lock()
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@staticmethod
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def destroy(repository, path=None):
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"""destroy the cache for ``repository`` or at ``path``"""
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path = path or os.path.join(get_cache_dir(), repository.id_str)
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config = os.path.join(path, 'config')
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if os.path.exists(config):
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os.remove(config) # kill config first
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shutil.rmtree(path)
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def __new__(cls, repository, key, manifest, path=None, sync=True, do_files=False, warn_if_unencrypted=True,
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progress=False, lock_wait=None, permit_adhoc_cache=False):
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def local():
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return LocalCache(repository=repository, key=key, manifest=manifest, path=path, sync=sync,
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do_files=do_files, warn_if_unencrypted=warn_if_unencrypted, progress=progress,
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lock_wait=lock_wait)
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def adhoc():
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return AdHocCache(repository=repository, key=key, manifest=manifest)
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if not permit_adhoc_cache:
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return local()
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# ad-hoc cache may be permitted, but if the local cache is in sync it'd be stupid to invalidate
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# it by needlessly using the ad-hoc cache.
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# Check if the local cache exists and is in sync.
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cache_config = CacheConfig(repository, path, lock_wait)
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if cache_config.exists():
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with cache_config:
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cache_in_sync = cache_config.manifest_id == manifest.id
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# Don't nest cache locks
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if cache_in_sync:
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# Local cache is in sync, use it
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logger.debug('Cache: choosing local cache (in sync)')
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return local()
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logger.debug('Cache: choosing ad-hoc cache (local cache does not exist or is not in sync)')
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return adhoc()
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|
|
|
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class CacheStatsMixin:
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str_format = """\
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All archives: {0.total_size:>20s} {0.total_csize:>20s} {0.unique_csize:>20s}
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Unique chunks Total chunks
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Chunk index: {0.total_unique_chunks:20d} {0.total_chunks:20d}"""
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def __str__(self):
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return self.str_format.format(self.format_tuple())
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Summary = namedtuple('Summary', ['total_size', 'total_csize', 'unique_size', 'unique_csize', 'total_unique_chunks',
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'total_chunks'])
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def stats(self):
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# XXX: this should really be moved down to `hashindex.pyx`
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stats = self.Summary(*self.chunks.summarize())._asdict()
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return stats
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|
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def format_tuple(self):
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stats = self.stats()
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for field in ['total_size', 'total_csize', 'unique_csize']:
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stats[field] = format_file_size(stats[field])
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return self.Summary(**stats)
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|
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def chunks_stored_size(self):
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return self.stats()['unique_csize']
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|
|
|
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class LocalCache(CacheStatsMixin):
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"""
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Persistent, local (client-side) cache.
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"""
|
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|
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def __init__(self, repository, key, manifest, path=None, sync=True, do_files=False, warn_if_unencrypted=True,
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progress=False, lock_wait=None):
|
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"""
|
|
:param do_files: use file metadata cache
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:param warn_if_unencrypted: print warning if accessing unknown unencrypted repository
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:param lock_wait: timeout for lock acquisition (None: return immediately if lock unavailable)
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:param sync: do :meth:`.sync`
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"""
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self.repository = repository
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self.key = key
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self.manifest = manifest
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self.progress = progress
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self.do_files = do_files
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self.timestamp = None
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self.txn_active = False
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|
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self.path = cache_dir(repository, path)
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self.security_manager = SecurityManager(repository)
|
|
self.cache_config = CacheConfig(self.repository, self.path, lock_wait)
|
|
|
|
# Warn user before sending data to a never seen before unencrypted repository
|
|
if not os.path.exists(self.path):
|
|
self.security_manager.assert_access_unknown(warn_if_unencrypted, manifest, key)
|
|
self.create()
|
|
|
|
self.open()
|
|
try:
|
|
self.security_manager.assert_secure(manifest, key, cache_config=self.cache_config)
|
|
|
|
if not self.check_cache_compatibility():
|
|
self.wipe_cache()
|
|
|
|
self.update_compatibility()
|
|
|
|
if sync and self.manifest.id != self.cache_config.manifest_id:
|
|
self.sync()
|
|
self.commit()
|
|
except:
|
|
self.close()
|
|
raise
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
self.close()
|
|
|
|
def create(self):
|
|
"""Create a new empty cache at `self.path`
|
|
"""
|
|
os.makedirs(self.path)
|
|
with open(os.path.join(self.path, 'README'), 'w') as fd:
|
|
fd.write(CACHE_README)
|
|
self.cache_config.create()
|
|
ChunkIndex().write(os.path.join(self.path, 'chunks'))
|
|
os.makedirs(os.path.join(self.path, 'chunks.archive.d'))
|
|
with SaveFile(os.path.join(self.path, 'files'), binary=True) as fd:
|
|
pass # empty file
|
|
|
|
def _do_open(self):
|
|
self.cache_config.load()
|
|
with IntegrityCheckedFile(path=os.path.join(self.path, 'chunks'), write=False,
|
|
integrity_data=self.cache_config.integrity.get('chunks')) as fd:
|
|
self.chunks = ChunkIndex.read(fd)
|
|
self.files = None
|
|
|
|
def open(self):
|
|
if not os.path.isdir(self.path):
|
|
raise Exception('%s Does not look like a Borg cache' % self.path)
|
|
self.cache_config.open()
|
|
self.rollback()
|
|
|
|
def close(self):
|
|
if self.cache_config is not None:
|
|
self.cache_config.close()
|
|
self.cache_config = None
|
|
|
|
def _read_files(self):
|
|
self.files = {}
|
|
self._newest_cmtime = None
|
|
logger.debug('Reading files cache ...')
|
|
|
|
with IntegrityCheckedFile(path=os.path.join(self.path, 'files'), write=False,
|
|
integrity_data=self.cache_config.integrity.get('files')) as fd:
|
|
u = msgpack.Unpacker(use_list=True)
|
|
while True:
|
|
data = fd.read(64 * 1024)
|
|
if not data:
|
|
break
|
|
u.feed(data)
|
|
try:
|
|
for path_hash, item in u:
|
|
entry = FileCacheEntry(*item)
|
|
# in the end, this takes about 240 Bytes per file
|
|
self.files[path_hash] = msgpack.packb(entry._replace(age=entry.age + 1))
|
|
except (TypeError, ValueError) as exc:
|
|
logger.warning('The files cache seems corrupt, ignoring it. '
|
|
'Expect lower performance. [%s]' % str(exc))
|
|
self.files = {}
|
|
return
|
|
|
|
def begin_txn(self):
|
|
# Initialize transaction snapshot
|
|
pi = ProgressIndicatorMessage(msgid='cache.begin_transaction')
|
|
txn_dir = os.path.join(self.path, 'txn.tmp')
|
|
os.mkdir(txn_dir)
|
|
pi.output('Initializing cache transaction: Reading config')
|
|
shutil.copy(os.path.join(self.path, 'config'), txn_dir)
|
|
pi.output('Initializing cache transaction: Reading chunks')
|
|
shutil.copy(os.path.join(self.path, 'chunks'), txn_dir)
|
|
pi.output('Initializing cache transaction: Reading files')
|
|
shutil.copy(os.path.join(self.path, 'files'), txn_dir)
|
|
os.rename(os.path.join(self.path, 'txn.tmp'),
|
|
os.path.join(self.path, 'txn.active'))
|
|
self.txn_active = True
|
|
pi.finish()
|
|
|
|
def commit(self):
|
|
"""Commit transaction
|
|
"""
|
|
if not self.txn_active:
|
|
return
|
|
self.security_manager.save(self.manifest, self.key)
|
|
pi = ProgressIndicatorMessage(msgid='cache.commit')
|
|
if self.files is not None:
|
|
if self._newest_cmtime is None:
|
|
# was never set because no files were modified/added
|
|
self._newest_cmtime = 2 ** 63 - 1 # nanoseconds, good until y2262
|
|
ttl = int(os.environ.get('BORG_FILES_CACHE_TTL', 20))
|
|
pi.output('Saving files cache')
|
|
with IntegrityCheckedFile(path=os.path.join(self.path, 'files'), write=True) as fd:
|
|
for path_hash, item in self.files.items():
|
|
# Only keep files seen in this backup that are older than newest cmtime seen in this backup -
|
|
# this is to avoid issues with filesystem snapshots and cmtime granularity.
|
|
# Also keep files from older backups that have not reached BORG_FILES_CACHE_TTL yet.
|
|
entry = FileCacheEntry(*msgpack.unpackb(item))
|
|
if entry.age == 0 and bigint_to_int(entry.cmtime) < self._newest_cmtime or \
|
|
entry.age > 0 and entry.age < ttl:
|
|
msgpack.pack((path_hash, entry), fd)
|
|
self.cache_config.integrity['files'] = fd.integrity_data
|
|
pi.output('Saving chunks cache')
|
|
with IntegrityCheckedFile(path=os.path.join(self.path, 'chunks'), write=True) as fd:
|
|
self.chunks.write(fd)
|
|
self.cache_config.integrity['chunks'] = fd.integrity_data
|
|
pi.output('Saving cache config')
|
|
self.cache_config.save(self.manifest, self.key)
|
|
os.rename(os.path.join(self.path, 'txn.active'),
|
|
os.path.join(self.path, 'txn.tmp'))
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
self.txn_active = False
|
|
pi.finish()
|
|
|
|
def rollback(self):
|
|
"""Roll back partial and aborted transactions
|
|
"""
|
|
# Remove partial transaction
|
|
if os.path.exists(os.path.join(self.path, 'txn.tmp')):
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
# Roll back active transaction
|
|
txn_dir = os.path.join(self.path, 'txn.active')
|
|
if os.path.exists(txn_dir):
|
|
shutil.copy(os.path.join(txn_dir, 'config'), self.path)
|
|
shutil.copy(os.path.join(txn_dir, 'chunks'), self.path)
|
|
shutil.copy(os.path.join(txn_dir, 'files'), self.path)
|
|
os.rename(txn_dir, os.path.join(self.path, 'txn.tmp'))
|
|
if os.path.exists(os.path.join(self.path, 'txn.tmp')):
|
|
shutil.rmtree(os.path.join(self.path, 'txn.tmp'))
|
|
self.txn_active = False
|
|
self._do_open()
|
|
|
|
def sync(self):
|
|
"""Re-synchronize chunks cache with repository.
|
|
|
|
Maintains a directory with known backup archive indexes, so it only
|
|
needs to fetch infos from repo and build a chunk index once per backup
|
|
archive.
|
|
If out of sync, missing archive indexes get added, outdated indexes
|
|
get removed and a new master chunks index is built by merging all
|
|
archive indexes.
|
|
"""
|
|
archive_path = os.path.join(self.path, 'chunks.archive.d')
|
|
# An index of chunks whose size had to be fetched
|
|
chunks_fetched_size_index = ChunkIndex()
|
|
# Instrumentation
|
|
processed_item_metadata_bytes = 0
|
|
processed_item_metadata_chunks = 0
|
|
compact_chunks_archive_saved_space = 0
|
|
fetched_chunks_for_csize = 0
|
|
fetched_bytes_for_csize = 0
|
|
|
|
def mkpath(id, suffix=''):
|
|
id_hex = bin_to_hex(id)
|
|
path = os.path.join(archive_path, id_hex + suffix)
|
|
return path
|
|
|
|
def cached_archives():
|
|
if self.do_cache:
|
|
fns = os.listdir(archive_path)
|
|
# filenames with 64 hex digits == 256bit,
|
|
# or compact indices which are 64 hex digits + ".compact"
|
|
return set(unhexlify(fn) for fn in fns if len(fn) == 64) | \
|
|
set(unhexlify(fn[:64]) for fn in fns if len(fn) == 72 and fn.endswith('.compact'))
|
|
else:
|
|
return set()
|
|
|
|
def repo_archives():
|
|
return set(info.id for info in self.manifest.archives.list())
|
|
|
|
def cleanup_outdated(ids):
|
|
for id in ids:
|
|
cleanup_cached_archive(id)
|
|
|
|
def cleanup_cached_archive(id, cleanup_compact=True):
|
|
try:
|
|
os.unlink(mkpath(id))
|
|
os.unlink(mkpath(id) + '.integrity')
|
|
except FileNotFoundError:
|
|
pass
|
|
if not cleanup_compact:
|
|
return
|
|
try:
|
|
os.unlink(mkpath(id, suffix='.compact'))
|
|
os.unlink(mkpath(id, suffix='.compact') + '.integrity')
|
|
except FileNotFoundError:
|
|
pass
|
|
|
|
def fetch_missing_csize(chunk_idx):
|
|
"""
|
|
Archives created with AdHocCache will have csize=0 in all chunk list entries whose
|
|
chunks were already in the repository.
|
|
|
|
Scan *chunk_idx* for entries where csize=0 and fill in the correct information.
|
|
"""
|
|
nonlocal fetched_chunks_for_csize
|
|
nonlocal fetched_bytes_for_csize
|
|
|
|
all_missing_ids = chunk_idx.zero_csize_ids()
|
|
fetch_ids = []
|
|
if len(chunks_fetched_size_index):
|
|
for id_ in all_missing_ids:
|
|
already_fetched_entry = chunks_fetched_size_index.get(id_)
|
|
if already_fetched_entry:
|
|
entry = chunk_idx[id_]._replace(csize=already_fetched_entry.csize)
|
|
assert entry.size == already_fetched_entry.size, 'Chunk size mismatch'
|
|
chunk_idx[id_] = entry
|
|
else:
|
|
fetch_ids.append(id_)
|
|
else:
|
|
fetch_ids = all_missing_ids
|
|
|
|
# This is potentially a rather expensive operation, but it's hard to tell at this point
|
|
# if it's a problem in practice (hence the experimental status of --no-cache-sync).
|
|
for id_, data in zip(fetch_ids, decrypted_repository.repository.get_many(fetch_ids)):
|
|
entry = chunk_idx[id_]._replace(csize=len(data))
|
|
chunk_idx[id_] = entry
|
|
chunks_fetched_size_index[id_] = entry
|
|
fetched_chunks_for_csize += 1
|
|
fetched_bytes_for_csize += len(data)
|
|
|
|
def fetch_and_build_idx(archive_id, decrypted_repository, chunk_idx):
|
|
nonlocal processed_item_metadata_bytes
|
|
nonlocal processed_item_metadata_chunks
|
|
csize, data = decrypted_repository.get(archive_id)
|
|
chunk_idx.add(archive_id, 1, len(data), csize)
|
|
archive = ArchiveItem(internal_dict=msgpack.unpackb(data))
|
|
if archive.version != 1:
|
|
raise Exception('Unknown archive metadata version')
|
|
sync = CacheSynchronizer(chunk_idx)
|
|
for item_id, (csize, data) in zip(archive.items, decrypted_repository.get_many(archive.items)):
|
|
chunk_idx.add(item_id, 1, len(data), csize)
|
|
processed_item_metadata_bytes += len(data)
|
|
processed_item_metadata_chunks += 1
|
|
sync.feed(data)
|
|
if self.do_cache:
|
|
fetch_missing_csize(chunk_idx)
|
|
write_archive_index(archive_id, chunk_idx)
|
|
|
|
def write_archive_index(archive_id, chunk_idx):
|
|
nonlocal compact_chunks_archive_saved_space
|
|
compact_chunks_archive_saved_space += chunk_idx.compact()
|
|
fn = mkpath(archive_id, suffix='.compact')
|
|
fn_tmp = mkpath(archive_id, suffix='.tmp')
|
|
try:
|
|
with DetachedIntegrityCheckedFile(path=fn_tmp, write=True,
|
|
filename=bin_to_hex(archive_id) + '.compact') as fd:
|
|
chunk_idx.write(fd)
|
|
except Exception:
|
|
truncate_and_unlink(fn_tmp)
|
|
else:
|
|
os.rename(fn_tmp, fn)
|
|
|
|
def read_archive_index(archive_id, archive_name):
|
|
archive_chunk_idx_path = mkpath(archive_id)
|
|
logger.info("Reading cached archive chunk index for %s ...", archive_name)
|
|
try:
|
|
try:
|
|
# Attempt to load compact index first
|
|
with DetachedIntegrityCheckedFile(path=archive_chunk_idx_path + '.compact', write=False) as fd:
|
|
archive_chunk_idx = ChunkIndex.read(fd, permit_compact=True)
|
|
# In case a non-compact index exists, delete it.
|
|
cleanup_cached_archive(archive_id, cleanup_compact=False)
|
|
# Compact index read - return index, no conversion necessary (below).
|
|
return archive_chunk_idx
|
|
except FileNotFoundError:
|
|
# No compact index found, load non-compact index, and convert below.
|
|
with DetachedIntegrityCheckedFile(path=archive_chunk_idx_path, write=False) as fd:
|
|
archive_chunk_idx = ChunkIndex.read(fd)
|
|
except FileIntegrityError as fie:
|
|
logger.error('Cached archive chunk index of %s is corrupted: %s', archive_name, fie)
|
|
# Delete corrupted index, set warning. A new index must be build.
|
|
cleanup_cached_archive(archive_id)
|
|
set_ec(EXIT_WARNING)
|
|
return None
|
|
|
|
# Convert to compact index. Delete the existing index first.
|
|
logger.debug('Found non-compact index for %s, converting to compact.', archive_name)
|
|
cleanup_cached_archive(archive_id)
|
|
write_archive_index(archive_id, archive_chunk_idx)
|
|
return archive_chunk_idx
|
|
|
|
def get_archive_ids_to_names(archive_ids):
|
|
# Pass once over all archives and build a mapping from ids to names.
|
|
# The easier approach, doing a similar loop for each archive, has
|
|
# square complexity and does about a dozen million functions calls
|
|
# with 1100 archives (which takes 30s CPU seconds _alone_).
|
|
archive_names = {}
|
|
for info in self.manifest.archives.list():
|
|
if info.id in archive_ids:
|
|
archive_names[info.id] = info.name
|
|
assert len(archive_names) == len(archive_ids)
|
|
return archive_names
|
|
|
|
def create_master_idx(chunk_idx):
|
|
logger.info('Synchronizing chunks cache...')
|
|
cached_ids = cached_archives()
|
|
archive_ids = repo_archives()
|
|
logger.info('Archives: %d, w/ cached Idx: %d, w/ outdated Idx: %d, w/o cached Idx: %d.',
|
|
len(archive_ids), len(cached_ids),
|
|
len(cached_ids - archive_ids), len(archive_ids - cached_ids))
|
|
# deallocates old hashindex, creates empty hashindex:
|
|
chunk_idx.clear()
|
|
cleanup_outdated(cached_ids - archive_ids)
|
|
# Explicitly set the initial hash table capacity to avoid performance issues
|
|
# due to hash table "resonance".
|
|
master_index_capacity = int(len(self.repository) / ChunkIndex.MAX_LOAD_FACTOR)
|
|
if archive_ids:
|
|
chunk_idx = None if not self.do_cache else ChunkIndex(master_index_capacity)
|
|
pi = ProgressIndicatorPercent(total=len(archive_ids), step=0.1,
|
|
msg='%3.0f%% Syncing chunks cache. Processing archive %s',
|
|
msgid='cache.sync')
|
|
archive_ids_to_names = get_archive_ids_to_names(archive_ids)
|
|
for archive_id, archive_name in archive_ids_to_names.items():
|
|
pi.show(info=[remove_surrogates(archive_name)])
|
|
if self.do_cache:
|
|
if archive_id in cached_ids:
|
|
archive_chunk_idx = read_archive_index(archive_id, archive_name)
|
|
if archive_chunk_idx is None:
|
|
cached_ids.remove(archive_id)
|
|
if archive_id not in cached_ids:
|
|
# Do not make this an else branch; the FileIntegrityError exception handler
|
|
# above can remove *archive_id* from *cached_ids*.
|
|
logger.info('Fetching and building archive index for %s ...', archive_name)
|
|
archive_chunk_idx = ChunkIndex()
|
|
fetch_and_build_idx(archive_id, decrypted_repository, archive_chunk_idx)
|
|
logger.info("Merging into master chunks index ...")
|
|
chunk_idx.merge(archive_chunk_idx)
|
|
else:
|
|
chunk_idx = chunk_idx or ChunkIndex(master_index_capacity)
|
|
logger.info('Fetching archive index for %s ...', archive_name)
|
|
fetch_and_build_idx(archive_id, decrypted_repository, chunk_idx)
|
|
if not self.do_cache:
|
|
fetch_missing_csize(chunk_idx)
|
|
pi.finish()
|
|
logger.debug('Cache sync: had to fetch %s (%d chunks) because no archive had a csize set for them '
|
|
'(due to --no-cache-sync)',
|
|
format_file_size(fetched_bytes_for_csize), fetched_chunks_for_csize)
|
|
logger.debug('Cache sync: processed %s (%d chunks) of metadata',
|
|
format_file_size(processed_item_metadata_bytes), processed_item_metadata_chunks)
|
|
logger.debug('Cache sync: compact chunks.archive.d storage saved %s bytes',
|
|
format_file_size(compact_chunks_archive_saved_space))
|
|
logger.info('Done.')
|
|
return chunk_idx
|
|
|
|
def legacy_cleanup():
|
|
"""bring old cache dirs into the desired state (cleanup and adapt)"""
|
|
try:
|
|
os.unlink(os.path.join(self.path, 'chunks.archive'))
|
|
except:
|
|
pass
|
|
try:
|
|
os.unlink(os.path.join(self.path, 'chunks.archive.tmp'))
|
|
except:
|
|
pass
|
|
try:
|
|
os.mkdir(archive_path)
|
|
except:
|
|
pass
|
|
|
|
# The cache can be used by a command that e.g. only checks against Manifest.Operation.WRITE,
|
|
# which does not have to include all flags from Manifest.Operation.READ.
|
|
# Since the sync will attempt to read archives, check compatibility with Manifest.Operation.READ.
|
|
self.manifest.check_repository_compatibility((Manifest.Operation.READ, ))
|
|
|
|
self.begin_txn()
|
|
with cache_if_remote(self.repository, decrypted_cache=self.key) as decrypted_repository:
|
|
legacy_cleanup()
|
|
# TEMPORARY HACK: to avoid archive index caching, create a FILE named ~/.cache/borg/REPOID/chunks.archive.d -
|
|
# this is only recommended if you have a fast, low latency connection to your repo (e.g. if repo is local disk)
|
|
self.do_cache = os.path.isdir(archive_path)
|
|
self.chunks = create_master_idx(self.chunks)
|
|
|
|
def check_cache_compatibility(self):
|
|
my_features = Manifest.SUPPORTED_REPO_FEATURES
|
|
if self.cache_config.ignored_features & my_features:
|
|
# The cache might not contain references of chunks that need a feature that is mandatory for some operation
|
|
# and which this version supports. To avoid corruption while executing that operation force rebuild.
|
|
return False
|
|
if not self.cache_config.mandatory_features <= my_features:
|
|
# The cache was build with consideration to at least one feature that this version does not understand.
|
|
# This client might misinterpret the cache. Thus force a rebuild.
|
|
return False
|
|
return True
|
|
|
|
def wipe_cache(self):
|
|
logger.warning("Discarding incompatible cache and forcing a cache rebuild")
|
|
archive_path = os.path.join(self.path, 'chunks.archive.d')
|
|
if os.path.isdir(archive_path):
|
|
shutil.rmtree(os.path.join(self.path, 'chunks.archive.d'))
|
|
os.makedirs(os.path.join(self.path, 'chunks.archive.d'))
|
|
self.chunks = ChunkIndex()
|
|
with open(os.path.join(self.path, 'files'), 'wb'):
|
|
pass # empty file
|
|
self.cache_config.manifest_id = ''
|
|
self.cache_config._config.set('cache', 'manifest', '')
|
|
|
|
self.cache_config.ignored_features = set()
|
|
self.cache_config.mandatory_features = set()
|
|
|
|
def update_compatibility(self):
|
|
operation_to_features_map = self.manifest.get_all_mandatory_features()
|
|
my_features = Manifest.SUPPORTED_REPO_FEATURES
|
|
repo_features = set()
|
|
for operation, features in operation_to_features_map.items():
|
|
repo_features.update(features)
|
|
|
|
self.cache_config.ignored_features.update(repo_features - my_features)
|
|
self.cache_config.mandatory_features.update(repo_features & my_features)
|
|
|
|
def add_chunk(self, id, chunk, stats, overwrite=False, wait=True):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
size = len(chunk)
|
|
refcount = self.seen_chunk(id, size)
|
|
if refcount and not overwrite:
|
|
return self.chunk_incref(id, stats)
|
|
data = self.key.encrypt(chunk)
|
|
csize = len(data)
|
|
self.repository.put(id, data, wait=wait)
|
|
self.chunks.add(id, 1, size, csize)
|
|
stats.update(size, csize, not refcount)
|
|
return ChunkListEntry(id, size, csize)
|
|
|
|
def seen_chunk(self, id, size=None):
|
|
refcount, stored_size, _ = self.chunks.get(id, ChunkIndexEntry(0, None, None))
|
|
if size is not None and stored_size is not None and size != stored_size:
|
|
# we already have a chunk with that id, but different size.
|
|
# this is either a hash collision (unlikely) or corruption or a bug.
|
|
raise Exception("chunk has same id [%r], but different size (stored: %d new: %d)!" % (
|
|
id, stored_size, size))
|
|
return refcount
|
|
|
|
def chunk_incref(self, id, stats, size=None):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
count, _size, csize = self.chunks.incref(id)
|
|
stats.update(_size, csize, False)
|
|
return ChunkListEntry(id, _size, csize)
|
|
|
|
def chunk_decref(self, id, stats, wait=True):
|
|
if not self.txn_active:
|
|
self.begin_txn()
|
|
count, size, csize = self.chunks.decref(id)
|
|
if count == 0:
|
|
del self.chunks[id]
|
|
self.repository.delete(id, wait=wait)
|
|
stats.update(-size, -csize, True)
|
|
else:
|
|
stats.update(-size, -csize, False)
|
|
|
|
def file_known_and_unchanged(self, path_hash, st, ignore_inode=False, cache_mode=DEFAULT_FILES_CACHE_MODE):
|
|
if 'd' in cache_mode or not self.do_files or not stat.S_ISREG(st.st_mode): # d(isabled)
|
|
return None
|
|
if self.files is None:
|
|
self._read_files()
|
|
if 'r' in cache_mode: # r(echunk)
|
|
return None
|
|
entry = self.files.get(path_hash)
|
|
if not entry:
|
|
return None
|
|
entry = FileCacheEntry(*msgpack.unpackb(entry))
|
|
if 's' in cache_mode and entry.size != st.st_size:
|
|
return None
|
|
if 'i' in cache_mode and not ignore_inode and entry.inode != st.st_ino:
|
|
return None
|
|
if 'c' in cache_mode and bigint_to_int(entry.cmtime) != st.st_ctime_ns:
|
|
return None
|
|
elif 'm' in cache_mode and bigint_to_int(entry.cmtime) != st.st_mtime_ns:
|
|
return None
|
|
# we ignored the inode number in the comparison above or it is still same.
|
|
# if it is still the same, replacing it in the tuple doesn't change it.
|
|
# if we ignored it, a reason for doing that is that files were moved to a new
|
|
# disk / new fs (so a one-time change of inode number is expected) and we wanted
|
|
# to avoid everything getting chunked again. to be able to re-enable the inode
|
|
# number comparison in a future backup run (and avoid chunking everything
|
|
# again at that time), we need to update the inode number in the cache with what
|
|
# we see in the filesystem.
|
|
self.files[path_hash] = msgpack.packb(entry._replace(inode=st.st_ino, age=0))
|
|
return entry.chunk_ids
|
|
|
|
def memorize_file(self, path_hash, st, ids, cache_mode=DEFAULT_FILES_CACHE_MODE):
|
|
# note: r(echunk) modes will update the files cache, d(isabled) mode won't
|
|
if 'd' in cache_mode or not self.do_files or not stat.S_ISREG(st.st_mode):
|
|
return
|
|
if 'c' in cache_mode:
|
|
cmtime_ns = safe_ns(st.st_ctime_ns)
|
|
elif 'm' in cache_mode:
|
|
cmtime_ns = safe_ns(st.st_mtime_ns)
|
|
entry = FileCacheEntry(age=0, inode=st.st_ino, size=st.st_size, cmtime=int_to_bigint(cmtime_ns), chunk_ids=ids)
|
|
self.files[path_hash] = msgpack.packb(entry)
|
|
self._newest_cmtime = max(self._newest_cmtime or 0, cmtime_ns)
|
|
|
|
|
|
class AdHocCache(CacheStatsMixin):
|
|
"""
|
|
Ad-hoc, non-persistent cache.
|
|
|
|
Compared to the standard LocalCache the AdHocCache does not maintain accurate reference count,
|
|
nor does it provide a files cache (which would require persistence). Chunks that were not added
|
|
during the current AdHocCache lifetime won't have correct size/csize set (0 bytes) and will
|
|
have an infinite reference count (MAX_VALUE).
|
|
"""
|
|
|
|
str_format = """\
|
|
All archives: unknown unknown unknown
|
|
|
|
Unique chunks Total chunks
|
|
Chunk index: {0.total_unique_chunks:20d} unknown"""
|
|
|
|
def __init__(self, repository, key, manifest, warn_if_unencrypted=True):
|
|
self.repository = repository
|
|
self.key = key
|
|
self.manifest = manifest
|
|
self._txn_active = False
|
|
|
|
self.security_manager = SecurityManager(repository)
|
|
self.security_manager.assert_secure(manifest, key)
|
|
|
|
logger.warning('Note: --no-cache-sync is an experimental feature.')
|
|
|
|
# Public API
|
|
|
|
def __enter__(self):
|
|
return self
|
|
|
|
def __exit__(self, exc_type, exc_val, exc_tb):
|
|
pass
|
|
|
|
files = None
|
|
do_files = False
|
|
|
|
def file_known_and_unchanged(self, path_hash, st, ignore_inode=False, cache_mode=DEFAULT_FILES_CACHE_MODE):
|
|
return None
|
|
|
|
def memorize_file(self, path_hash, st, ids, cache_mode=DEFAULT_FILES_CACHE_MODE):
|
|
pass
|
|
|
|
def add_chunk(self, id, chunk, stats, overwrite=False, wait=True):
|
|
assert not overwrite, 'AdHocCache does not permit overwrites — trying to use it for recreate?'
|
|
if not self._txn_active:
|
|
self._begin_txn()
|
|
size = len(chunk)
|
|
refcount = self.seen_chunk(id, size)
|
|
if refcount:
|
|
return self.chunk_incref(id, stats, size=size)
|
|
data = self.key.encrypt(chunk)
|
|
csize = len(data)
|
|
self.repository.put(id, data, wait=wait)
|
|
self.chunks.add(id, 1, size, csize)
|
|
stats.update(size, csize, not refcount)
|
|
return ChunkListEntry(id, size, csize)
|
|
|
|
def seen_chunk(self, id, size=None):
|
|
if not self._txn_active:
|
|
self._begin_txn()
|
|
entry = self.chunks.get(id, ChunkIndexEntry(0, None, None))
|
|
if entry.refcount and size and not entry.size:
|
|
# The LocalCache has existing size information and uses *size* to make an effort at detecting collisions.
|
|
# This is of course not possible for the AdHocCache.
|
|
# Here *size* is used to update the chunk's size information, which will be zero for existing chunks.
|
|
self.chunks[id] = entry._replace(size=size)
|
|
return entry.refcount
|
|
|
|
def chunk_incref(self, id, stats, size=None):
|
|
if not self._txn_active:
|
|
self._begin_txn()
|
|
count, _size, csize = self.chunks.incref(id)
|
|
# When _size is 0 and size is not given, then this chunk has not been locally visited yet (seen_chunk with
|
|
# size or add_chunk); we can't add references to those (size=0 is invalid) and generally don't try to.
|
|
size = _size or size
|
|
assert size
|
|
stats.update(size, csize, False)
|
|
return ChunkListEntry(id, size, csize)
|
|
|
|
def chunk_decref(self, id, stats, wait=True):
|
|
if not self._txn_active:
|
|
self._begin_txn()
|
|
count, size, csize = self.chunks.decref(id)
|
|
if count == 0:
|
|
del self.chunks[id]
|
|
self.repository.delete(id, wait=wait)
|
|
stats.update(-size, -csize, True)
|
|
else:
|
|
stats.update(-size, -csize, False)
|
|
|
|
def commit(self):
|
|
if not self._txn_active:
|
|
return
|
|
self.security_manager.save(self.manifest, self.key)
|
|
self._txn_active = False
|
|
|
|
def rollback(self):
|
|
self._txn_active = False
|
|
del self.chunks
|
|
|
|
# Private API
|
|
|
|
def _begin_txn(self):
|
|
self._txn_active = True
|
|
# Explicitly set the initial hash table capacity to avoid performance issues
|
|
# due to hash table "resonance".
|
|
# Since we're creating an archive, add 10 % from the start.
|
|
num_chunks = len(self.repository)
|
|
capacity = int(num_chunks / ChunkIndex.MAX_LOAD_FACTOR * 1.1)
|
|
self.chunks = ChunkIndex(capacity)
|
|
pi = ProgressIndicatorPercent(total=num_chunks, msg='Downloading chunk list... %3.0f%%',
|
|
msgid='cache.download_chunks')
|
|
t0 = perf_counter()
|
|
num_requests = 0
|
|
marker = None
|
|
while True:
|
|
result = self.repository.list(limit=LIST_SCAN_LIMIT, marker=marker)
|
|
num_requests += 1
|
|
if not result:
|
|
break
|
|
pi.show(increase=len(result))
|
|
marker = result[-1]
|
|
# All chunks from the repository have a refcount of MAX_VALUE, which is sticky,
|
|
# therefore we can't/won't delete them. Chunks we added ourselves in this transaction
|
|
# (e.g. checkpoint archives) are tracked correctly.
|
|
init_entry = ChunkIndexEntry(refcount=ChunkIndex.MAX_VALUE, size=0, csize=0)
|
|
for id_ in result:
|
|
self.chunks[id_] = init_entry
|
|
assert len(self.chunks) == num_chunks
|
|
# LocalCache does not contain the manifest, either.
|
|
del self.chunks[self.manifest.MANIFEST_ID]
|
|
duration = perf_counter() - t0 or 0.01
|
|
pi.finish()
|
|
logger.debug('AdHocCache: downloaded %d chunk IDs in %.2f s (%d requests), ~%s/s',
|
|
num_chunks, duration, num_requests, format_file_size(num_chunks * 34 / duration))
|
|
# Chunk IDs in a list are encoded in 34 bytes: 1 byte msgpack header, 1 byte length, 32 ID bytes.
|
|
# Protocol overhead is neglected in this calculation.
|