import errno import functools import inspect import json import logging import os import select import shlex import shutil import struct import sys import tempfile import textwrap import time import traceback from subprocess import Popen, PIPE from . import __version__ from .compress import Compressor from .constants import * # NOQA from .helpers import Error, IntegrityError from .helpers import bin_to_hex from .helpers import get_base_dir from .helpers import get_limited_unpacker from .helpers import replace_placeholders from .helpers import sysinfo from .helpers import format_file_size from .helpers import safe_unlink from .helpers import prepare_subprocess_env, ignore_sigint from .logger import create_logger, setup_logging from .helpers import msgpack from .repository import Repository from .version import parse_version, format_version from .algorithms.checksums import xxh64 from .helpers.datastruct import EfficientCollectionQueue logger = create_logger(__name__) RPC_PROTOCOL_VERSION = 2 BORG_VERSION = parse_version(__version__) MSGID, MSG, ARGS, RESULT = b'i', b'm', b'a', b'r' MAX_INFLIGHT = 100 RATELIMIT_PERIOD = 0.1 def os_write(fd, data): """os.write wrapper so we do not lose data for partial writes.""" # TODO: this issue is fixed in cygwin since at least 2.8.0, remove this # wrapper / workaround when this version is considered ancient. # This is happening frequently on cygwin due to its small pipe buffer size of only 64kiB # and also due to its different blocking pipe behaviour compared to Linux/*BSD. # Neither Linux nor *BSD ever do partial writes on blocking pipes, unless interrupted by a # signal, in which case serve() would terminate. amount = remaining = len(data) while remaining: count = os.write(fd, data) remaining -= count if not remaining: break data = data[count:] time.sleep(count * 1e-09) return amount class ConnectionClosed(Error): """Connection closed by remote host""" class ConnectionClosedWithHint(ConnectionClosed): """Connection closed by remote host. {}""" class PathNotAllowed(Error): """Repository path not allowed: {}""" class InvalidRPCMethod(Error): """RPC method {} is not valid""" class UnexpectedRPCDataFormatFromClient(Error): """Borg {}: Got unexpected RPC data format from client.""" class UnexpectedRPCDataFormatFromServer(Error): """Got unexpected RPC data format from server:\n{}""" def __init__(self, data): try: data = data.decode()[:128] except UnicodeDecodeError: data = data[:128] data = ['%02X' % byte for byte in data] data = textwrap.fill(' '.join(data), 16 * 3) super().__init__(data) # Protocol compatibility: # In general the server is responsible for rejecting too old clients and the client it responsible for rejecting # too old servers. This ensures that the knowledge what is compatible is always held by the newer component. # # The server can do checks for the client version in RepositoryServer.negotiate. If the client_data is 2 then # client is in the version range [0.29.0, 1.0.x] inclusive. For newer clients client_data is a dict which contains # client_version. # # For the client the return of the negotiate method is either 2 if the server is in the version range [0.29.0, 1.0.x] # inclusive, or it is a dict which includes the server version. # # All method calls on the remote repository object must be allowlisted in RepositoryServer.rpc_methods and have api # stubs in RemoteRepository. The @api decorator on these stubs is used to set server version requirements. # # Method parameters are identified only by name and never by position. Unknown parameters are ignored by the server side. # If a new parameter is important and may not be ignored, on the client a parameter specific version requirement needs # to be added. # When parameters are removed, they need to be preserved as defaulted parameters on the client stubs so that older # servers still get compatible input. compatMap = { 'check': ('repair', 'save_space', ), 'commit': ('save_space', ), 'rollback': (), 'destroy': (), '__len__': (), 'list': ('limit', 'marker', ), 'put': ('id', 'data', ), 'get': ('id', ), 'delete': ('id', ), 'save_key': ('keydata', ), 'load_key': (), 'break_lock': (), 'negotiate': ('client_data', ), 'open': ('path', 'create', 'lock_wait', 'lock', 'exclusive', 'append_only', ), 'get_free_nonce': (), 'commit_nonce_reservation': ('next_unreserved', 'start_nonce', ), } def decode_keys(d): return {k.decode(): d[k] for k in d} class RepositoryServer: # pragma: no cover rpc_methods = ( '__len__', 'check', 'commit', 'delete', 'destroy', 'get', 'list', 'scan', 'negotiate', 'open', 'put', 'rollback', 'save_key', 'load_key', 'break_lock', 'get_free_nonce', 'commit_nonce_reservation', 'inject_exception', ) def __init__(self, restrict_to_paths, restrict_to_repositories, append_only, storage_quota): self.repository = None self.restrict_to_paths = restrict_to_paths self.restrict_to_repositories = restrict_to_repositories # This flag is parsed from the serve command line via Archiver.do_serve, # i.e. it reflects local system policy and generally ranks higher than # whatever the client wants, except when initializing a new repository # (see RepositoryServer.open below). self.append_only = append_only self.storage_quota = storage_quota self.client_version = parse_version('1.0.8') # fallback version if client is too old to send version information def positional_to_named(self, method, argv): """Translate from positional protocol to named protocol.""" try: return {name: argv[pos] for pos, name in enumerate(compatMap[method])} except IndexError: if method == 'open' and len(argv) == 4: # borg clients < 1.0.7 use open() with 4 args mapping = compatMap[method][:4] else: raise return {name: argv[pos] for pos, name in enumerate(mapping)} def filter_args(self, f, kwargs): """Remove unknown named parameters from call, because client did (implicitly) say it's ok.""" known = set(inspect.signature(f).parameters) return {name: kwargs[name] for name in kwargs if name in known} def serve(self): stdin_fd = sys.stdin.fileno() stdout_fd = sys.stdout.fileno() stderr_fd = sys.stdout.fileno() os.set_blocking(stdin_fd, False) os.set_blocking(stdout_fd, True) os.set_blocking(stderr_fd, True) unpacker = get_limited_unpacker('server') while True: r, w, es = select.select([stdin_fd], [], [], 10) if r: data = os.read(stdin_fd, BUFSIZE) if not data: if self.repository is not None: self.repository.close() else: os_write(stderr_fd, 'Borg {}: Got connection close before repository was opened.\n' .format(__version__).encode()) return unpacker.feed(data) for unpacked in unpacker: if isinstance(unpacked, dict): dictFormat = True msgid = unpacked[MSGID] method = unpacked[MSG].decode() args = decode_keys(unpacked[ARGS]) elif isinstance(unpacked, tuple) and len(unpacked) == 4: dictFormat = False # The first field 'type' was always 1 and has always been ignored _, msgid, method, args = unpacked method = method.decode() args = self.positional_to_named(method, args) else: if self.repository is not None: self.repository.close() raise UnexpectedRPCDataFormatFromClient(__version__) try: if method not in self.rpc_methods: raise InvalidRPCMethod(method) try: f = getattr(self, method) except AttributeError: f = getattr(self.repository, method) args = self.filter_args(f, args) res = f(**args) except BaseException as e: if dictFormat: ex_short = traceback.format_exception_only(e.__class__, e) ex_full = traceback.format_exception(*sys.exc_info()) ex_trace = True if isinstance(e, Error): ex_short = [e.get_message()] ex_trace = e.traceback if isinstance(e, (Repository.DoesNotExist, Repository.AlreadyExists, PathNotAllowed)): # These exceptions are reconstructed on the client end in RemoteRepository.call_many(), # and will be handled just like locally raised exceptions. Suppress the remote traceback # for these, except ErrorWithTraceback, which should always display a traceback. pass else: logging.debug('\n'.join(ex_full)) try: msg = msgpack.packb({MSGID: msgid, b'exception_class': e.__class__.__name__, b'exception_args': e.args, b'exception_full': ex_full, b'exception_short': ex_short, b'exception_trace': ex_trace, b'sysinfo': sysinfo()}) except TypeError: msg = msgpack.packb({MSGID: msgid, b'exception_class': e.__class__.__name__, b'exception_args': [x if isinstance(x, (str, bytes, int)) else None for x in e.args], b'exception_full': ex_full, b'exception_short': ex_short, b'exception_trace': ex_trace, b'sysinfo': sysinfo()}) os_write(stdout_fd, msg) else: if isinstance(e, (Repository.DoesNotExist, Repository.AlreadyExists, PathNotAllowed)): # These exceptions are reconstructed on the client end in RemoteRepository.call_many(), # and will be handled just like locally raised exceptions. Suppress the remote traceback # for these, except ErrorWithTraceback, which should always display a traceback. pass else: if isinstance(e, Error): tb_log_level = logging.ERROR if e.traceback else logging.DEBUG msg = e.get_message() else: tb_log_level = logging.ERROR msg = '%s Exception in RPC call' % e.__class__.__name__ tb = f'{traceback.format_exc()}\n{sysinfo()}' logging.error(msg) logging.log(tb_log_level, tb) exc = 'Remote Exception (see remote log for the traceback)' os_write(stdout_fd, msgpack.packb((1, msgid, e.__class__.__name__, exc))) else: if dictFormat: os_write(stdout_fd, msgpack.packb({MSGID: msgid, RESULT: res})) else: os_write(stdout_fd, msgpack.packb((1, msgid, None, res))) if es: self.repository.close() return def negotiate(self, client_data): # old format used in 1.0.x if client_data == RPC_PROTOCOL_VERSION: return RPC_PROTOCOL_VERSION # clients since 1.1.0b3 use a dict as client_data # clients since 1.1.0b6 support json log format from server if isinstance(client_data, dict): self.client_version = client_data[b'client_version'] level = logging.getLevelName(logging.getLogger('').level) setup_logging(is_serve=True, json=True, level=level) logger.debug('Initialized logging system for JSON-based protocol') else: self.client_version = BORG_VERSION # seems to be newer than current version (no known old format) # not a known old format, send newest negotiate this version knows return {'server_version': BORG_VERSION} def _resolve_path(self, path): if isinstance(path, bytes): path = os.fsdecode(path) # Leading slash is always present with URI (ssh://), but not with short-form (who@host:path). if path.startswith('/~/'): # /~/x = path x relative to home dir path = os.path.join(get_base_dir(), path[3:]) elif path.startswith('~/'): path = os.path.join(get_base_dir(), path[2:]) elif path.startswith('/~'): # /~username/x = relative to "user" home dir path = os.path.expanduser(path[1:]) elif path.startswith('~'): path = os.path.expanduser(path) elif path.startswith('/./'): # /./x = path x relative to cwd path = path[3:] return os.path.realpath(path) def open(self, path, create=False, lock_wait=None, lock=True, exclusive=None, append_only=False, make_parent_dirs=False): logging.debug('Resolving repository path %r', path) path = self._resolve_path(path) logging.debug('Resolved repository path to %r', path) path_with_sep = os.path.join(path, '') # make sure there is a trailing slash (os.sep) if self.restrict_to_paths: # if --restrict-to-path P is given, we make sure that we only operate in/below path P. # for the prefix check, it is important that the compared paths both have trailing slashes, # so that a path /foobar will NOT be accepted with --restrict-to-path /foo option. for restrict_to_path in self.restrict_to_paths: restrict_to_path_with_sep = os.path.join(os.path.realpath(restrict_to_path), '') # trailing slash if path_with_sep.startswith(restrict_to_path_with_sep): break else: raise PathNotAllowed(path) if self.restrict_to_repositories: for restrict_to_repository in self.restrict_to_repositories: restrict_to_repository_with_sep = os.path.join(os.path.realpath(restrict_to_repository), '') if restrict_to_repository_with_sep == path_with_sep: break else: raise PathNotAllowed(path) # "borg init" on "borg serve --append-only" (=self.append_only) does not create an append only repo, # while "borg init --append-only" (=append_only) does, regardless of the --append-only (self.append_only) # flag for serve. append_only = (not create and self.append_only) or append_only self.repository = Repository(path, create, lock_wait=lock_wait, lock=lock, append_only=append_only, storage_quota=self.storage_quota, exclusive=exclusive, make_parent_dirs=make_parent_dirs) self.repository.__enter__() # clean exit handled by serve() method return self.repository.id def inject_exception(self, kind): kind = kind.decode() s1 = 'test string' s2 = 'test string2' if kind == 'DoesNotExist': raise Repository.DoesNotExist(s1) elif kind == 'AlreadyExists': raise Repository.AlreadyExists(s1) elif kind == 'CheckNeeded': raise Repository.CheckNeeded(s1) elif kind == 'IntegrityError': raise IntegrityError(s1) elif kind == 'PathNotAllowed': raise PathNotAllowed('foo') elif kind == 'ObjectNotFound': raise Repository.ObjectNotFound(s1, s2) elif kind == 'InvalidRPCMethod': raise InvalidRPCMethod(s1) elif kind == 'divide': 0 // 0 class SleepingBandwidthLimiter: def __init__(self, limit): if limit: self.ratelimit = int(limit * RATELIMIT_PERIOD) self.ratelimit_last = time.monotonic() self.ratelimit_quota = self.ratelimit else: self.ratelimit = None def write(self, fd, to_send): if self.ratelimit: now = time.monotonic() if self.ratelimit_last + RATELIMIT_PERIOD <= now: self.ratelimit_quota += self.ratelimit if self.ratelimit_quota > 2 * self.ratelimit: self.ratelimit_quota = 2 * self.ratelimit self.ratelimit_last = now if self.ratelimit_quota == 0: tosleep = self.ratelimit_last + RATELIMIT_PERIOD - now time.sleep(tosleep) self.ratelimit_quota += self.ratelimit self.ratelimit_last = time.monotonic() if len(to_send) > self.ratelimit_quota: to_send = to_send[:self.ratelimit_quota] written = os.write(fd, to_send) if self.ratelimit: self.ratelimit_quota -= written return written def api(*, since, **kwargs_decorator): """Check version requirements and use self.call to do the remote method call. specifies the version in which borg introduced this method. Calling this method when connected to an older version will fail without transmitting anything to the server. Further kwargs can be used to encode version specific restrictions: is the value resulting in the behaviour before introducing the new parameter. If a previous hardcoded behaviour is parameterized in a version, this allows calls that use the previously hardcoded behaviour to pass through and generates an error if another behaviour is requested by the client. E.g. when 'append_only' was introduced in 1.0.7 the previous behaviour was what now is append_only=False. Thus @api(..., append_only={'since': parse_version('1.0.7'), 'previously': False}) allows calls with append_only=False for all version but rejects calls using append_only=True on versions older than 1.0.7. is a flag to set the behaviour if an old version is called the new way. If set to True, the method is called without the (not yet supported) parameter (this should be done if that is the more desirable behaviour). If False, an exception is generated. E.g. before 'threshold' was introduced in 1.2.0a8, a hardcoded threshold of 0.1 was used in commit(). """ def decorator(f): @functools.wraps(f) def do_rpc(self, *args, **kwargs): sig = inspect.signature(f) bound_args = sig.bind(self, *args, **kwargs) named = {} # Arguments for the remote process extra = {} # Arguments for the local process for name, param in sig.parameters.items(): if name == 'self': continue if name in bound_args.arguments: if name == 'wait': extra[name] = bound_args.arguments[name] else: named[name] = bound_args.arguments[name] else: if param.default is not param.empty: named[name] = param.default if self.server_version < since: raise self.RPCServerOutdated(f.__name__, format_version(since)) for name, restriction in kwargs_decorator.items(): if restriction['since'] <= self.server_version: continue if 'previously' in restriction and named[name] == restriction['previously']: continue if restriction.get('dontcare', False): continue raise self.RPCServerOutdated(f"{f.__name__} {name}={named[name]!s}", format_version(restriction['since'])) return self.call(f.__name__, named, **extra) return do_rpc return decorator class RemoteRepository: extra_test_args = [] class RPCError(Exception): def __init__(self, unpacked): # for borg < 1.1: unpacked only has b'exception_class' as key # for borg 1.1+: unpacked has keys: b'exception_args', b'exception_full', b'exception_short', b'sysinfo' self.unpacked = unpacked def get_message(self): if b'exception_short' in self.unpacked: return b'\n'.join(self.unpacked[b'exception_short']).decode() else: return self.exception_class @property def traceback(self): return self.unpacked.get(b'exception_trace', True) @property def exception_class(self): return self.unpacked[b'exception_class'].decode() @property def exception_full(self): if b'exception_full' in self.unpacked: return b'\n'.join(self.unpacked[b'exception_full']).decode() else: return self.get_message() + '\nRemote Exception (see remote log for the traceback)' @property def sysinfo(self): if b'sysinfo' in self.unpacked: return self.unpacked[b'sysinfo'].decode() else: return '' class RPCServerOutdated(Error): """Borg server is too old for {}. Required version {}""" @property def method(self): return self.args[0] @property def required_version(self): return self.args[1] # If compatibility with 1.0.x is not longer needed, replace all checks of this with True and simplify the code dictFormat = False # outside of __init__ for testing of legacy free protocol def __init__(self, location, create=False, exclusive=False, lock_wait=None, lock=True, append_only=False, make_parent_dirs=False, args=None): self.location = self._location = location self.preload_ids = [] self.msgid = 0 self.rx_bytes = 0 self.tx_bytes = 0 self.to_send = EfficientCollectionQueue(1024 * 1024, bytes) self.stderr_received = b'' # incomplete stderr line bytes received (no \n yet) self.chunkid_to_msgids = {} self.ignore_responses = set() self.responses = {} self.async_responses = {} self.shutdown_time = None self.ratelimit = SleepingBandwidthLimiter(args.upload_ratelimit * 1024 if args and args.upload_ratelimit else 0) self.upload_buffer_size_limit = args.upload_buffer * 1024 * 1024 if args and args.upload_buffer else 0 self.unpacker = get_limited_unpacker('client') self.server_version = parse_version('1.0.8') # fallback version if server is too old to send version information self.p = None self._args = args testing = location.host == '__testsuite__' # when testing, we invoke and talk to a borg process directly (no ssh). # when not testing, we invoke the system-installed ssh binary to talk to a remote borg. env = prepare_subprocess_env(system=not testing) borg_cmd = self.borg_cmd(args, testing) if not testing: borg_cmd = self.ssh_cmd(location) + borg_cmd logger.debug('SSH command line: %s', borg_cmd) # we do not want the ssh getting killed by Ctrl-C/SIGINT because it is needed for clean shutdown of borg. # borg's SIGINT handler tries to write a checkpoint and requires the remote repo connection. self.p = Popen(borg_cmd, bufsize=0, stdin=PIPE, stdout=PIPE, stderr=PIPE, env=env, preexec_fn=ignore_sigint) self.stdin_fd = self.p.stdin.fileno() self.stdout_fd = self.p.stdout.fileno() self.stderr_fd = self.p.stderr.fileno() os.set_blocking(self.stdin_fd, False) os.set_blocking(self.stdout_fd, False) os.set_blocking(self.stderr_fd, False) self.r_fds = [self.stdout_fd, self.stderr_fd] self.x_fds = [self.stdin_fd, self.stdout_fd, self.stderr_fd] try: try: version = self.call('negotiate', {'client_data': { b'client_version': BORG_VERSION, }}) except ConnectionClosed: raise ConnectionClosedWithHint('Is borg working on the server?') from None if version == RPC_PROTOCOL_VERSION: self.dictFormat = False elif isinstance(version, dict) and b'server_version' in version: self.dictFormat = True self.server_version = version[b'server_version'] else: raise Exception('Server insisted on using unsupported protocol version %s' % version) def do_open(): self.id = self.open(path=self.location.path, create=create, lock_wait=lock_wait, lock=lock, exclusive=exclusive, append_only=append_only, make_parent_dirs=make_parent_dirs) if self.dictFormat: do_open() else: # Ugly detection of versions prior to 1.0.7: If open throws it has to be 1.0.6 or lower try: do_open() except self.RPCError as err: if err.exception_class != 'TypeError': raise msg = """\ Please note: If you see a TypeError complaining about the number of positional arguments given to open(), you can ignore it if it comes from a borg version < 1.0.7. This TypeError is a cosmetic side effect of the compatibility code borg clients >= 1.0.7 have to support older borg servers. This problem will go away as soon as the server has been upgraded to 1.0.7+. """ # emit this msg in the same way as the 'Remote: ...' lines that show the remote TypeError sys.stderr.write(msg) self.server_version = parse_version('1.0.6') compatMap['open'] = ('path', 'create', 'lock_wait', 'lock', ) # try again with corrected version and compatMap do_open() except Exception: self.close() raise def __del__(self): if len(self.responses): logging.debug('still %d cached responses left in RemoteRepository' % (len(self.responses),)) if self.p: self.close() assert False, 'cleanup happened in Repository.__del__' def __repr__(self): return f'<{self.__class__.__name__} {self.location.canonical_path()}>' def __enter__(self): return self def __exit__(self, exc_type, exc_val, exc_tb): try: if exc_type is not None: self.shutdown_time = time.monotonic() + 30 self.rollback() finally: # in any case, we want to cleanly close the repo, even if the # rollback can not succeed (e.g. because the connection was # already closed) and raised another exception: logger.debug('RemoteRepository: %s bytes sent, %s bytes received, %d messages sent', format_file_size(self.tx_bytes), format_file_size(self.rx_bytes), self.msgid) self.close() @property def id_str(self): return bin_to_hex(self.id) def borg_cmd(self, args, testing): """return a borg serve command line""" # give some args/options to 'borg serve' process as they were given to us opts = [] if args is not None: root_logger = logging.getLogger() if root_logger.isEnabledFor(logging.DEBUG): opts.append('--debug') elif root_logger.isEnabledFor(logging.INFO): opts.append('--info') elif root_logger.isEnabledFor(logging.WARNING): pass # warning is default elif root_logger.isEnabledFor(logging.ERROR): opts.append('--error') elif root_logger.isEnabledFor(logging.CRITICAL): opts.append('--critical') else: raise ValueError('log level missing, fix this code') # Tell the remote server about debug topics it may need to consider. # Note that debug topics are usable for "spew" or "trace" logs which would # be too plentiful to transfer for normal use, so the server doesn't send # them unless explicitly enabled. # # Needless to say, if you do --debug-topic=repository.compaction, for example, # with a 1.0.x server it won't work, because the server does not recognize the # option. # # This is not considered a problem, since this is a debugging feature that # should not be used for regular use. for topic in args.debug_topics: if '.' not in topic: topic = 'borg.debug.' + topic if 'repository' in topic: opts.append('--debug-topic=%s' % topic) if 'storage_quota' in args and args.storage_quota: opts.append('--storage-quota=%s' % args.storage_quota) env_vars = [] if testing: return env_vars + [sys.executable, '-m', 'borg.archiver', 'serve'] + opts + self.extra_test_args else: # pragma: no cover remote_path = args.remote_path or os.environ.get('BORG_REMOTE_PATH', 'borg') remote_path = replace_placeholders(remote_path) return env_vars + [remote_path, 'serve'] + opts def ssh_cmd(self, location): """return a ssh command line that can be prefixed to a borg command line""" rsh = self._args.rsh or os.environ.get('BORG_RSH', 'ssh') args = shlex.split(rsh) if location.port: args += ['-p', str(location.port)] if location.user: args.append(f'{location.user}@{location.host}') else: args.append('%s' % location.host) return args def named_to_positional(self, method, kwargs): return [kwargs[name] for name in compatMap[method]] def call(self, cmd, args, **kw): for resp in self.call_many(cmd, [args], **kw): return resp def call_many(self, cmd, calls, wait=True, is_preloaded=False, async_wait=True): if not calls and cmd != 'async_responses': return def send_buffer(): if self.to_send: try: written = self.ratelimit.write(self.stdin_fd, self.to_send.peek_front()) self.tx_bytes += written self.to_send.pop_front(written) except OSError as e: # io.write might raise EAGAIN even though select indicates # that the fd should be writable. # EWOULDBLOCK is added for defensive programming sake. if e.errno not in [errno.EAGAIN, errno.EWOULDBLOCK]: raise def pop_preload_msgid(chunkid): msgid = self.chunkid_to_msgids[chunkid].pop(0) if not self.chunkid_to_msgids[chunkid]: del self.chunkid_to_msgids[chunkid] return msgid def handle_error(unpacked): error = unpacked[b'exception_class'].decode() old_server = b'exception_args' not in unpacked args = unpacked.get(b'exception_args') if error == 'DoesNotExist': raise Repository.DoesNotExist(self.location.processed) elif error == 'AlreadyExists': raise Repository.AlreadyExists(self.location.processed) elif error == 'CheckNeeded': raise Repository.CheckNeeded(self.location.processed) elif error == 'IntegrityError': if old_server: raise IntegrityError('(not available)') else: raise IntegrityError(args[0].decode()) elif error == 'AtticRepository': if old_server: raise Repository.AtticRepository('(not available)') else: raise Repository.AtticRepository(args[0].decode()) elif error == 'PathNotAllowed': if old_server: raise PathNotAllowed('(unknown)') else: raise PathNotAllowed(args[0].decode()) elif error == 'ParentPathDoesNotExist': raise Repository.ParentPathDoesNotExist(args[0].decode()) elif error == 'ObjectNotFound': if old_server: raise Repository.ObjectNotFound('(not available)', self.location.processed) else: raise Repository.ObjectNotFound(args[0].decode(), self.location.processed) elif error == 'InvalidRPCMethod': if old_server: raise InvalidRPCMethod('(not available)') else: raise InvalidRPCMethod(args[0].decode()) else: raise self.RPCError(unpacked) calls = list(calls) waiting_for = [] maximum_to_send = 0 if wait else self.upload_buffer_size_limit send_buffer() # Try to send data, as some cases (async_response) will never try to send data otherwise. while wait or calls: if self.shutdown_time and time.monotonic() > self.shutdown_time: # we are shutting this RemoteRepository down already, make sure we do not waste # a lot of time in case a lot of async stuff is coming in or remote is gone or slow. logger.debug('shutdown_time reached, shutting down with %d waiting_for and %d async_responses.', len(waiting_for), len(self.async_responses)) return while waiting_for: try: unpacked = self.responses.pop(waiting_for[0]) waiting_for.pop(0) if b'exception_class' in unpacked: handle_error(unpacked) else: yield unpacked[RESULT] if not waiting_for and not calls: return except KeyError: break if cmd == 'async_responses': while True: try: msgid, unpacked = self.async_responses.popitem() except KeyError: # there is nothing left what we already have received if async_wait and self.ignore_responses: # but do not return if we shall wait and there is something left to wait for: break else: return else: if b'exception_class' in unpacked: handle_error(unpacked) else: yield unpacked[RESULT] if self.to_send or ((calls or self.preload_ids) and len(waiting_for) < MAX_INFLIGHT): w_fds = [self.stdin_fd] else: w_fds = [] r, w, x = select.select(self.r_fds, w_fds, self.x_fds, 1) if x: raise Exception('FD exception occurred') for fd in r: if fd is self.stdout_fd: data = os.read(fd, BUFSIZE) if not data: raise ConnectionClosed() self.rx_bytes += len(data) self.unpacker.feed(data) for unpacked in self.unpacker: if isinstance(unpacked, dict): msgid = unpacked[MSGID] elif isinstance(unpacked, tuple) and len(unpacked) == 4: # The first field 'type' was always 1 and has always been ignored _, msgid, error, res = unpacked if error: # ignore res, because it is only a fixed string anyway. unpacked = {MSGID: msgid, b'exception_class': error} else: unpacked = {MSGID: msgid, RESULT: res} else: raise UnexpectedRPCDataFormatFromServer(data) if msgid in self.ignore_responses: self.ignore_responses.remove(msgid) # async methods never return values, but may raise exceptions. if b'exception_class' in unpacked: self.async_responses[msgid] = unpacked else: # we currently do not have async result values except "None", # so we do not add them into async_responses. if unpacked[RESULT] is not None: self.async_responses[msgid] = unpacked else: self.responses[msgid] = unpacked elif fd is self.stderr_fd: data = os.read(fd, 32768) if not data: raise ConnectionClosed() self.rx_bytes += len(data) # deal with incomplete lines (may appear due to block buffering) if self.stderr_received: data = self.stderr_received + data self.stderr_received = b'' lines = data.splitlines(keepends=True) if lines and not lines[-1].endswith((b'\r', b'\n')): self.stderr_received = lines.pop() # now we have complete lines in and any partial line in self.stderr_received. for line in lines: handle_remote_line(line.decode()) # decode late, avoid partial utf-8 sequences if w: while (len(self.to_send) <= maximum_to_send) and (calls or self.preload_ids) and len(waiting_for) < MAX_INFLIGHT: if calls: if is_preloaded: assert cmd == 'get', "is_preload is only supported for 'get'" if calls[0]['id'] in self.chunkid_to_msgids: waiting_for.append(pop_preload_msgid(calls.pop(0)['id'])) else: args = calls.pop(0) if cmd == 'get' and args['id'] in self.chunkid_to_msgids: waiting_for.append(pop_preload_msgid(args['id'])) else: self.msgid += 1 waiting_for.append(self.msgid) if self.dictFormat: self.to_send.push_back(msgpack.packb({MSGID: self.msgid, MSG: cmd, ARGS: args})) else: self.to_send.push_back(msgpack.packb((1, self.msgid, cmd, self.named_to_positional(cmd, args)))) if not self.to_send and self.preload_ids: chunk_id = self.preload_ids.pop(0) args = {'id': chunk_id} self.msgid += 1 self.chunkid_to_msgids.setdefault(chunk_id, []).append(self.msgid) if self.dictFormat: self.to_send.push_back(msgpack.packb({MSGID: self.msgid, MSG: 'get', ARGS: args})) else: self.to_send.push_back(msgpack.packb((1, self.msgid, 'get', self.named_to_positional('get', args)))) send_buffer() self.ignore_responses |= set(waiting_for) # we lose order here @api(since=parse_version('1.0.0'), append_only={'since': parse_version('1.0.7'), 'previously': False}, make_parent_dirs={'since': parse_version('1.1.9'), 'previously': False}) def open(self, path, create=False, lock_wait=None, lock=True, exclusive=False, append_only=False, make_parent_dirs=False): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0'), max_duration={'since': parse_version('1.2.0a4'), 'previously': 0}) def check(self, repair=False, save_space=False, max_duration=0): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0'), compact={'since': parse_version('1.2.0a0'), 'previously': True, 'dontcare': True}, threshold={'since': parse_version('1.2.0a8'), 'previously': 0.1, 'dontcare': True}, cleanup_commits={'since': parse_version('1.2.0a0'), 'previously': False, 'dontcare': True}) def commit(self, save_space=False, compact=True, threshold=0.1, cleanup_commits=False): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def rollback(self): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def destroy(self): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def __len__(self): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def list(self, limit=None, marker=None): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.1.0b3')) def scan(self, limit=None, marker=None): """actual remoting is done via self.call in the @api decorator""" def get(self, id): for resp in self.get_many([id]): return resp def get_many(self, ids, is_preloaded=False): yield from self.call_many('get', [{'id': id} for id in ids], is_preloaded=is_preloaded) @api(since=parse_version('1.0.0')) def put(self, id, data, wait=True): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def delete(self, id, wait=True): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def save_key(self, keydata): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def load_key(self): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def get_free_nonce(self): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def commit_nonce_reservation(self, next_unreserved, start_nonce): """actual remoting is done via self.call in the @api decorator""" @api(since=parse_version('1.0.0')) def break_lock(self): """actual remoting is done via self.call in the @api decorator""" def close(self): if self.p: self.p.stdin.close() self.p.stdout.close() self.p.wait() self.p = None def async_response(self, wait=True): for resp in self.call_many('async_responses', calls=[], wait=True, async_wait=wait): return resp def preload(self, ids): self.preload_ids += ids def handle_remote_line(line): """ Handle a remote log line. This function is remarkably complex because it handles multiple wire formats. """ assert line.endswith(('\r', '\n')) if line.startswith('{'): # This format is used by Borg since 1.1.0b6 for new-protocol clients. # It is the same format that is exposed by --log-json. msg = json.loads(line) if msg['type'] not in ('progress_message', 'progress_percent', 'log_message'): logger.warning('Dropped remote log message with unknown type %r: %s', msg['type'], line) return if msg['type'] == 'log_message': # Re-emit log messages on the same level as the remote to get correct log suppression and verbosity. level = getattr(logging, msg['levelname'], logging.CRITICAL) assert isinstance(level, int) target_logger = logging.getLogger(msg['name']) msg['message'] = 'Remote: ' + msg['message'] # In JSON mode, we manually check whether the log message should be propagated. if logging.getLogger('borg').json and level >= target_logger.getEffectiveLevel(): sys.stderr.write(json.dumps(msg) + '\n') else: target_logger.log(level, '%s', msg['message']) elif msg['type'].startswith('progress_'): # Progress messages are a bit more complex. # First of all, we check whether progress output is enabled. This is signalled # through the effective level of the borg.output.progress logger # (also see ProgressIndicatorBase in borg.helpers). progress_logger = logging.getLogger('borg.output.progress') if progress_logger.getEffectiveLevel() == logging.INFO: # When progress output is enabled, we check whether the client is in # --log-json mode, as signalled by the "json" attribute on the "borg" logger. if logging.getLogger('borg').json: # In --log-json mode we re-emit the progress JSON line as sent by the server, # with the message, if any, prefixed with "Remote: ". if 'message' in msg: msg['message'] = 'Remote: ' + msg['message'] sys.stderr.write(json.dumps(msg) + '\n') elif 'message' in msg: # In text log mode we write only the message to stderr and terminate with \r # (carriage return, i.e. move the write cursor back to the beginning of the line) # so that the next message, progress or not, overwrites it. This mirrors the behaviour # of local progress displays. sys.stderr.write('Remote: ' + msg['message'] + '\r') elif line.startswith('$LOG '): # This format is used by borg serve 0.xx, 1.0.x and 1.1.0b1..b5. # It prefixed log lines with $LOG as a marker, followed by the log level # and optionally a logger name, then "Remote:" as a separator followed by the original # message. _, level, msg = line.split(' ', 2) level = getattr(logging, level, logging.CRITICAL) # str -> int if msg.startswith('Remote:'): # server format: '$LOG Remote: ' logging.log(level, msg.rstrip()) else: # server format '$LOG Remote: ' logname, msg = msg.split(' ', 1) logging.getLogger(logname).log(level, msg.rstrip()) else: # Plain 1.0.x and older format - re-emit to stderr (mirroring what the 1.0.x # client did) or as a generic log message. # We don't know what priority the line had. if logging.getLogger('borg').json: logging.getLogger('').warning('Remote: ' + line.strip()) else: # In non-JSON mode we circumvent logging to preserve carriage returns (\r) # which are generated by remote progress displays. sys.stderr.write('Remote: ' + line) class RepositoryNoCache: """A not caching Repository wrapper, passes through to repository. Just to have same API (including the context manager) as RepositoryCache. *transform* is a callable taking two arguments, key and raw repository data. The return value is returned from get()/get_many(). By default, the raw repository data is returned. """ def __init__(self, repository, transform=None): self.repository = repository self.transform = transform or (lambda key, data: data) def close(self): pass def __enter__(self): return self def __exit__(self, exc_type, exc_val, exc_tb): self.close() def get(self, key): return next(self.get_many([key], cache=False)) def get_many(self, keys, cache=True): for key, data in zip(keys, self.repository.get_many(keys)): yield self.transform(key, data) def log_instrumentation(self): pass class RepositoryCache(RepositoryNoCache): """ A caching Repository wrapper. Caches Repository GET operations locally. *pack* and *unpack* complement *transform* of the base class. *pack* receives the output of *transform* and should return bytes, which are stored in the cache. *unpack* receives these bytes and should return the initial data (as returned by *transform*). """ def __init__(self, repository, pack=None, unpack=None, transform=None): super().__init__(repository, transform) self.pack = pack or (lambda data: data) self.unpack = unpack or (lambda data: data) self.cache = set() self.basedir = tempfile.mkdtemp(prefix='borg-cache-') self.query_size_limit() self.size = 0 # Instrumentation self.hits = 0 self.misses = 0 self.slow_misses = 0 self.slow_lat = 0.0 self.evictions = 0 self.enospc = 0 def query_size_limit(self): available_space = shutil.disk_usage(self.basedir).free self.size_limit = int(min(available_space * 0.25, 2**31)) def key_filename(self, key): return os.path.join(self.basedir, bin_to_hex(key)) def backoff(self): self.query_size_limit() target_size = int(0.9 * self.size_limit) while self.size > target_size and self.cache: key = self.cache.pop() file = self.key_filename(key) self.size -= os.stat(file).st_size os.unlink(file) self.evictions += 1 def add_entry(self, key, data, cache): transformed = self.transform(key, data) if not cache: return transformed packed = self.pack(transformed) file = self.key_filename(key) try: with open(file, 'wb') as fd: fd.write(packed) except OSError as os_error: try: safe_unlink(file) except FileNotFoundError: pass # open() could have failed as well if os_error.errno == errno.ENOSPC: self.enospc += 1 self.backoff() else: raise else: self.size += len(packed) self.cache.add(key) if self.size > self.size_limit: self.backoff() return transformed def log_instrumentation(self): logger.debug('RepositoryCache: current items %d, size %s / %s, %d hits, %d misses, %d slow misses (+%.1fs), ' '%d evictions, %d ENOSPC hit', len(self.cache), format_file_size(self.size), format_file_size(self.size_limit), self.hits, self.misses, self.slow_misses, self.slow_lat, self.evictions, self.enospc) def close(self): self.log_instrumentation() self.cache.clear() shutil.rmtree(self.basedir) def get_many(self, keys, cache=True): unknown_keys = [key for key in keys if key not in self.cache] repository_iterator = zip(unknown_keys, self.repository.get_many(unknown_keys)) for key in keys: if key in self.cache: file = self.key_filename(key) with open(file, 'rb') as fd: self.hits += 1 yield self.unpack(fd.read()) else: for key_, data in repository_iterator: if key_ == key: transformed = self.add_entry(key, data, cache) self.misses += 1 yield transformed break else: # slow path: eviction during this get_many removed this key from the cache t0 = time.perf_counter() data = self.repository.get(key) self.slow_lat += time.perf_counter() - t0 transformed = self.add_entry(key, data, cache) self.slow_misses += 1 yield transformed # Consume any pending requests for _ in repository_iterator: pass def cache_if_remote(repository, *, decrypted_cache=False, pack=None, unpack=None, transform=None, force_cache=False): """ Return a Repository(No)Cache for *repository*. If *decrypted_cache* is a key object, then get and get_many will return a tuple (csize, plaintext) instead of the actual data in the repository. The cache will store decrypted data, which increases CPU efficiency (by avoiding repeatedly decrypting and more importantly MAC and ID checking cached objects). Internally, objects are compressed with LZ4. """ if decrypted_cache and (pack or unpack or transform): raise ValueError('decrypted_cache and pack/unpack/transform are incompatible') elif decrypted_cache: key = decrypted_cache # 32 bit csize, 64 bit (8 byte) xxh64 cache_struct = struct.Struct('=I8s') compressor = Compressor('lz4') def pack(data): csize, decrypted = data compressed = compressor.compress(decrypted) return cache_struct.pack(csize, xxh64(compressed)) + compressed def unpack(data): data = memoryview(data) csize, checksum = cache_struct.unpack(data[:cache_struct.size]) compressed = data[cache_struct.size:] if checksum != xxh64(compressed): raise IntegrityError('detected corrupted data in metadata cache') return csize, compressor.decompress(compressed) def transform(id_, data): csize = len(data) decrypted = key.decrypt(id_, data) return csize, decrypted if isinstance(repository, RemoteRepository) or force_cache: return RepositoryCache(repository, pack, unpack, transform) else: return RepositoryNoCache(repository, transform)