# server.py -- Implementation of the server side git protocols # Copyright (C) 2008 John Carr # Copyright(C) 2011-2012 Jelmer Vernooij # # SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later # Dulwich is dual-licensed under the Apache License, Version 2.0 and the GNU # General Public License as published by the Free Software Foundation; version 2.0 # or (at your option) any later version. You can redistribute it and/or # modify it under the terms of either of these two licenses. # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # # You should have received a copy of the licenses; if not, see # for a copy of the GNU General Public License # and for a copy of the Apache # License, Version 2.0. # """Git smart network protocol server implementation. For more detailed implementation on the network protocol, see the Documentation/technical directory in the cgit distribution, and in particular: * Documentation/technical/protocol-capabilities.txt * Documentation/technical/pack-protocol.txt Currently supported capabilities: * include-tag * thin-pack * multi_ack_detailed * multi_ack * side-band-64k * ofs-delta * no-progress * report-status * delete-refs * shallow * symref """ __all__ = [ "DEFAULT_HANDLERS", "AckGraphWalkerImpl", "Backend", "BackendRepo", "DictBackend", "FileSystemBackend", "Handler", "MultiAckDetailedGraphWalkerImpl", "MultiAckGraphWalkerImpl", "PackHandler", "ReceivePackHandler", "SingleAckGraphWalkerImpl", "TCPGitRequestHandler", "TCPGitServer", "UploadArchiveHandler", "UploadPackHandler", "generate_info_refs", "generate_objects_info_packs", "main", "serve_command", "update_server_info", ] import os import socket import socketserver import sys import time import zlib from collections import deque from collections.abc import Callable, Iterable, Iterator, Mapping, Sequence from collections.abc import Set as AbstractSet from functools import partial from typing import IO, TYPE_CHECKING from typing import Protocol as TypingProtocol if TYPE_CHECKING: from .object_format import ObjectFormat from .object_store import BaseObjectStore from .repo import BaseRepo from dulwich import log_utils from .archive import tar_stream from .errors import ( ApplyDeltaError, ChecksumMismatch, GitProtocolError, HookError, NotGitRepository, ObjectFormatException, UnexpectedCommandError, ) from .object_filters import ( CombineFilter, FilterSpec, SparseOidFilter, TreeDepthFilter, filter_pack_objects, filter_pack_objects_with_paths, parse_filter_spec, ) from .object_store import MissingObjectFinder, PackBasedObjectStore, find_shallow from .objects import Commit, ObjectID, Tree, valid_hexsha from .pack import ObjectContainer, write_pack_from_container from .protocol import ( CAPABILITIES_REF, CAPABILITY_AGENT, CAPABILITY_ATOMIC, CAPABILITY_DELETE_REFS, CAPABILITY_FILTER, CAPABILITY_INCLUDE_TAG, CAPABILITY_MULTI_ACK, CAPABILITY_MULTI_ACK_DETAILED, CAPABILITY_NO_DONE, CAPABILITY_NO_PROGRESS, CAPABILITY_OFS_DELTA, CAPABILITY_QUIET, CAPABILITY_REPORT_STATUS, CAPABILITY_SHALLOW, CAPABILITY_SIDE_BAND_64K, CAPABILITY_THIN_PACK, COMMAND_DEEPEN, COMMAND_DONE, COMMAND_FILTER, COMMAND_HAVE, COMMAND_SHALLOW, COMMAND_UNSHALLOW, COMMAND_WANT, MULTI_ACK, MULTI_ACK_DETAILED, NAK_LINE, PEELED_TAG_SUFFIX, SIDE_BAND_CHANNEL_DATA, SIDE_BAND_CHANNEL_FATAL, SIDE_BAND_CHANNEL_PROGRESS, SINGLE_ACK, TCP_GIT_PORT, BufferedPktLineWriter, Protocol, ReceivableProtocol, ack_type, capability_agent, capability_object_format, extract_capabilities, extract_want_line_capabilities, find_capability, format_ack_line, format_ref_line, format_shallow_line, format_unshallow_line, symref_capabilities, write_info_refs, ) from .refs import Ref, RefsContainer from .repo import Repo logger = log_utils.getLogger(__name__) class Backend: """A backend for the Git smart server implementation.""" def open_repository(self, path: str) -> "BackendRepo": """Open the repository at a path. Args: path: Path to the repository Raises: NotGitRepository: no git repository was found at path Returns: Instance of BackendRepo """ raise NotImplementedError(self.open_repository) class BackendRepo(TypingProtocol): """Repository abstraction used by the Git server. The methods required here are a subset of those provided by dulwich.repo.Repo. """ # Declared as properties (read-only) rather than attributes so that # implementations exposing more specific subtypes (e.g. Repo, whose # object_store is a DiskObjectStore) still satisfy this protocol. # Mutable Protocol attributes are invariant, which would reject any # such subtype. @property def object_store(self) -> PackBasedObjectStore: """Object store backing this repository.""" raise NotImplementedError @property def refs(self) -> RefsContainer: """Refs container for this repository.""" raise NotImplementedError @property def object_format(self) -> "ObjectFormat": """Hash algorithm used by this repository.""" raise NotImplementedError def get_refs(self) -> dict[Ref, ObjectID]: """Get all the refs in the repository. Returns: dict of name -> sha """ raise NotImplementedError def get_peeled(self, ref: Ref) -> ObjectID | None: """Return the cached peeled value of a ref, if available. Args: ref: Name of the ref to peel Returns: The peeled value of the ref. If the ref is known not point to a tag, this will be the SHA the ref refers to. If no cached information about a tag is available, this method may return None, but it should attempt to peel the tag if possible. """ return None def find_missing_objects( self, determine_wants: Callable[[Mapping[Ref, ObjectID], int | None], list[ObjectID]], graph_walker: "_ProtocolGraphWalker", progress: Callable[[bytes], None] | None, *, get_tagged: Callable[[], dict[ObjectID, ObjectID]] | None = None, depth: int | None = None, ) -> "MissingObjectFinder | None": """Yield the objects required for a list of commits. Args: determine_wants: Function to determine which objects the client wants graph_walker: Object used to walk the commit graph progress: is a callback to send progress messages to the client get_tagged: Function that returns a dict of pointed-to sha -> tag sha for including tags. depth: Maximum depth of commits to fetch for shallow clones """ raise NotImplementedError class DictBackend(Backend): """Trivial backend that looks up Git repositories in a dictionary.""" def __init__( self, repos: dict[bytes, "BackendRepo"] | dict[str, "BackendRepo"] ) -> None: """Initialize a DictBackend. Args: repos: Dictionary mapping repository paths to BackendRepo instances. Keys may be either str or bytes; both forms are accepted on lookup. """ self.repos = repos def open_repository(self, path: str) -> BackendRepo: """Open repository at given path. Args: path: Path to the repository Returns: Repository object Raises: NotGitRepository: If no repository found at path """ logger.debug("Opening repository at %s", path) # repos may be keyed by either str or bytes (or both, since # the constructor accepts a union of dict types and callers # may also mutate it after construction). Walk the items so we # don't have to index into the union and so we transparently # match str and bytes representations of the same path. path_bytes: bytes | None try: path_bytes = path.encode("utf-8") if isinstance(path, str) else path except UnicodeEncodeError: path_bytes = None try: path_str: str | None = ( path if isinstance(path, str) else path.decode("utf-8") ) except UnicodeDecodeError: path_str = None for key, repo in self.repos.items(): if isinstance(key, bytes): if key == path_bytes: return repo else: if key == path_str: return repo raise NotGitRepository( "No git repository was found at {path}".format(**dict(path=path)) ) class FileSystemBackend(Backend): """Simple backend looking up Git repositories in the local file system.""" def __init__(self, root: str = os.sep) -> None: """Initialize a FileSystemBackend. Args: root: Root directory to serve repositories from """ super().__init__() self.root = (os.path.abspath(root) + os.sep).replace(os.sep * 2, os.sep) def open_repository(self, path: str) -> BackendRepo: """Open a repository from the filesystem. Args: path: Path to the repository relative to the root Returns: Repo instance Raises: NotGitRepository: If path is outside the root or not a git repository """ logger.debug("opening repository at %s", path) # Ensure path is a string to avoid TypeError when joining with self.root path = os.fspath(path) if isinstance(path, bytes): path = os.fsdecode(path) abspath = os.path.abspath(os.path.join(self.root, path)) + os.sep normcase_abspath = os.path.normcase(abspath) normcase_root = os.path.normcase(self.root) if not normcase_abspath.startswith(normcase_root): raise NotGitRepository(f"Path {path!r} not inside root {self.root!r}") return Repo(abspath) class Handler: """Smart protocol command handler base class.""" def __init__( self, backend: Backend, proto: Protocol, stateless_rpc: bool = False ) -> None: """Initialize a Handler. Args: backend: Backend instance for repository access proto: Protocol instance for communication stateless_rpc: Whether this is a stateless RPC session """ self.backend = backend self.proto = proto self.stateless_rpc = stateless_rpc def handle(self) -> None: """Handle a request.""" raise NotImplementedError(self.handle) class PackHandler(Handler): """Protocol handler for packs.""" def __init__( self, backend: Backend, proto: Protocol, stateless_rpc: bool = False ) -> None: """Initialize a PackHandler. Args: backend: Backend instance for repository access proto: Protocol instance for communication stateless_rpc: Whether this is a stateless RPC session """ super().__init__(backend, proto, stateless_rpc) self._client_capabilities: set[bytes] | None = None # Flags needed for the no-done capability self._done_received = False self.advertise_refs = False def capabilities(self) -> Iterable[bytes]: """Return a list of capabilities supported by this handler.""" raise NotImplementedError(self.capabilities) @classmethod def innocuous_capabilities(cls) -> Iterable[bytes]: """Return capabilities that don't affect protocol behavior. Returns: List of innocuous capability names """ return [ CAPABILITY_INCLUDE_TAG, CAPABILITY_THIN_PACK, CAPABILITY_NO_PROGRESS, CAPABILITY_OFS_DELTA, capability_agent(), ] @classmethod def required_capabilities(cls) -> Iterable[bytes]: """Return a list of capabilities that we require the client to have.""" return [] def set_client_capabilities(self, caps: Iterable[bytes]) -> None: """Set the client capabilities and validate them. Args: caps: List of capabilities requested by the client Raises: GitProtocolError: If client requests unsupported capability or lacks required ones """ allowable_caps = set(self.innocuous_capabilities()) allowable_caps.update(self.capabilities()) for cap in caps: if cap.startswith(CAPABILITY_AGENT + b"="): continue if cap.startswith(CAPABILITY_FILTER + b"="): # Filter capability can have a value (e.g., filter=blob:none) if CAPABILITY_FILTER not in allowable_caps: raise GitProtocolError( f"Client asked for capability {cap!r} that was not advertised." ) continue if cap not in allowable_caps: raise GitProtocolError( f"Client asked for capability {cap!r} that was not advertised." ) for cap in self.required_capabilities(): if cap not in caps: raise GitProtocolError( f"Client does not support required capability {cap!r}." ) self._client_capabilities = set(caps) logger.info("Client capabilities: %s", caps) def has_capability(self, cap: bytes) -> bool: """Check if the client supports a specific capability. Args: cap: Capability name to check Returns: True if the client supports the capability Raises: GitProtocolError: If called before client capabilities are set """ if self._client_capabilities is None: raise GitProtocolError( f"Server attempted to access capability {cap!r} before asking client" ) return cap in self._client_capabilities def notify_done(self) -> None: """Notify that the 'done' command has been received from the client.""" self._done_received = True class UploadPackHandler(PackHandler): """Protocol handler for uploading a pack to the client.""" def __init__( self, backend: Backend, args: Sequence[str], proto: Protocol, stateless_rpc: bool = False, advertise_refs: bool = False, ) -> None: """Initialize an UploadPackHandler. Args: backend: Backend instance for repository access args: Command arguments (first arg is repository path) proto: Protocol instance for communication stateless_rpc: Whether this is a stateless RPC session advertise_refs: Whether to advertise refs """ super().__init__(backend, proto, stateless_rpc=stateless_rpc) self.repo = backend.open_repository(args[0]) self._graph_walker = None self.advertise_refs = advertise_refs # A state variable for denoting that the have list is still # being processed, and the client is not accepting any other # data (such as side-band, see the progress method here). self._processing_have_lines = False # Filter specification for partial clone support self.filter_spec: FilterSpec | None = None def capabilities(self) -> list[bytes]: """Return the list of capabilities supported by upload-pack. Returns: List of capabilities including object-format for the repository """ return [ CAPABILITY_MULTI_ACK_DETAILED, CAPABILITY_MULTI_ACK, CAPABILITY_SIDE_BAND_64K, CAPABILITY_THIN_PACK, CAPABILITY_OFS_DELTA, CAPABILITY_NO_PROGRESS, CAPABILITY_INCLUDE_TAG, CAPABILITY_SHALLOW, CAPABILITY_NO_DONE, CAPABILITY_FILTER, capability_object_format(self.repo.object_format.name), ] @classmethod def required_capabilities(cls) -> tuple[bytes, ...]: """Return the list of capabilities required for upload-pack.""" return ( CAPABILITY_SIDE_BAND_64K, CAPABILITY_THIN_PACK, CAPABILITY_OFS_DELTA, ) def set_client_capabilities(self, caps: Iterable[bytes]) -> None: """Set client capabilities and parse filter specification if present. Args: caps: List of capability strings from the client """ super().set_client_capabilities(caps) # Parse filter specification if present in capabilities # In protocol v1, filter can be sent as "filter=" capability # In protocol v2, filter is sent as a separate "filter " command filter_spec_bytes = find_capability(caps, CAPABILITY_FILTER) if filter_spec_bytes and filter_spec_bytes != CAPABILITY_FILTER: # Only parse if there's an actual spec (not just the capability name) try: self.filter_spec = parse_filter_spec( filter_spec_bytes, object_store=self.repo.object_store ) except ValueError as e: raise GitProtocolError(f"Invalid filter specification: {e}") def progress(self, message: bytes) -> None: """Send a progress message to the client. Args: message: Progress message to send """ def _start_pack_send_phase(self) -> None: """Start the pack sending phase, setting up sideband if supported.""" if self.has_capability(CAPABILITY_SIDE_BAND_64K): # The provided haves are processed, and it is safe to send side- # band data now. if not self.has_capability(CAPABILITY_NO_PROGRESS): self.progress = partial( # type: ignore self.proto.write_sideband, SIDE_BAND_CHANNEL_PROGRESS ) self.write_pack_data: Callable[[bytes], None] = partial( self.proto.write_sideband, SIDE_BAND_CHANNEL_DATA ) else: # proto.write returns Optional[int], but we need to treat it as returning None # for compatibility with write_pack_from_container def write_data(data: bytes) -> None: self.proto.write(data) self.write_pack_data = write_data def get_tagged( self, refs: Mapping[Ref, ObjectID] | None = None, repo: BackendRepo | None = None, ) -> dict[ObjectID, ObjectID]: """Get a dict of peeled values of tags to their original tag shas. Args: refs: dict of refname -> sha of possible tags; defaults to all of the backend's refs. repo: optional Repo instance for getting peeled refs; defaults to the backend's repo, if available Returns: dict of peeled_sha -> tag_sha, where tag_sha is the sha of a tag whose peeled value is peeled_sha. """ if not self.has_capability(CAPABILITY_INCLUDE_TAG): return {} if refs is None: refs = self.repo.get_refs() if repo is None: repo = getattr(self.repo, "repo", None) if repo is None: # Bail if we don't have a Repo available; this is ok since # clients must be able to handle if the server doesn't include # all relevant tags. # TODO: fix behavior when missing return {} # TODO(jelmer): Integrate this with the refs logic in # Repo.find_missing_objects tagged = {} for name, sha in refs.items(): peeled_sha = repo.get_peeled(name) if peeled_sha is not None and peeled_sha != ObjectID(sha): tagged[peeled_sha] = ObjectID(sha) return tagged def handle(self) -> None: """Handle an upload-pack request. This method processes the client's wants and haves, determines which objects to send, and writes the pack data to the client. """ # Note the fact that client is only processing responses related # to the have lines it sent, and any other data (including side- # band) will be be considered a fatal error. self._processing_have_lines = True graph_walker = _ProtocolGraphWalker( self, self.repo.object_store, self.repo.get_peeled, self.repo.refs.get_symrefs, ) wants: list[ObjectID] = [] def wants_wrapper( refs: Mapping[Ref, ObjectID], depth: int | None = None ) -> list[ObjectID]: wants.extend(graph_walker.determine_wants(refs, depth)) return wants missing_objects = self.repo.find_missing_objects( wants_wrapper, graph_walker, self.progress, get_tagged=self.get_tagged, ) # Did the process short-circuit (e.g. in a stateless RPC call)? Note # that the client still expects a 0-object pack in most cases. # Also, if it also happens that the object_iter is instantiated # with a graph walker with an implementation that talks over the # wire (which is this instance of this class) this will actually # iterate through everything and write things out to the wire. if len(wants) == 0: return # Handle shallow clone case where missing_objects can be None if missing_objects is None: return object_ids = list(missing_objects) if not graph_walker.handle_done( not self.has_capability(CAPABILITY_NO_DONE), self._done_received ): return self._start_pack_send_phase() # Apply filter if specified (partial clone support) if self.filter_spec is not None: original_count = len(object_ids) # Use path-aware filtering for tree depth and sparse:oid filters # Check if filter requires path tracking def needs_path_tracking(filter_spec: FilterSpec) -> bool: if isinstance(filter_spec, TreeDepthFilter | SparseOidFilter): return True if isinstance(filter_spec, CombineFilter): return any(needs_path_tracking(f) for f in filter_spec.filters) return False if needs_path_tracking(self.filter_spec): # Path-aware filtering returns list of OIDs, convert to tuples for pack generation filtered_oids = filter_pack_objects_with_paths( self.repo.object_store, wants, self.filter_spec, progress=self.progress, ) object_ids = [(oid, None) for oid in filtered_oids] else: # Extract just the object IDs (filter_pack_objects expects list of OIDs) # object_ids is a list of tuples (oid, (depth, path)) oid_list = [oid for oid, _hint in object_ids] filtered_oids = filter_pack_objects( self.repo.object_store, oid_list, self.filter_spec ) # Reconstruct tuples with hints for pack generation filtered_oid_set = set(filtered_oids) object_ids = [ (oid, hint) for oid, hint in object_ids if oid in filtered_oid_set ] filtered_count = original_count - len(object_ids) if filtered_count > 0: self.progress((f"filtered {filtered_count} objects.\n").encode("ascii")) self.progress((f"counting objects: {len(object_ids)}, done.\n").encode("ascii")) write_pack_from_container( self.write_pack_data, self.repo.object_store, object_ids, object_format=self.repo.object_format, ) # we are done self.proto.write_pkt_line(None) def _split_proto_line( line: bytes | None, allowed: Iterable[bytes | None] | None ) -> tuple[bytes | None, bytes | int | None]: """Split a line read from the wire. Args: line: The line read from the wire. allowed: An iterable of command names that should be allowed. Command names not listed below as possible return values will be ignored. If None, any commands from the possible return values are allowed. Returns: a tuple having one of the following forms: ('want', obj_id) ('have', obj_id) ('done', None) (None, None) (for a flush-pkt) Raises: UnexpectedCommandError: if the line cannot be parsed into one of the allowed return values. """ if not line: fields: list[bytes | None] = [None] else: fields = list(line.rstrip(b"\n").split(b" ", 1)) command = fields[0] if allowed is not None and command not in allowed: raise UnexpectedCommandError(command.decode("utf-8") if command else None) if len(fields) == 1 and command in (COMMAND_DONE, None): return (command, None) elif len(fields) == 2: if command in ( COMMAND_WANT, COMMAND_HAVE, COMMAND_SHALLOW, COMMAND_UNSHALLOW, ): assert fields[1] is not None if not valid_hexsha(fields[1]): raise GitProtocolError("Invalid sha") return (command, fields[1]) elif command == COMMAND_DEEPEN: assert fields[1] is not None return command, int(fields[1]) elif command == COMMAND_FILTER: # Filter specification (e.g., "filter blob:none") assert fields[1] is not None return (command, fields[1]) raise GitProtocolError(f"Received invalid line from client: {line!r}") def _want_satisfied( store: ObjectContainer, haves: set[ObjectID], want: ObjectID, earliest: int ) -> bool: """Check if a specific want is satisfied by a set of haves. Args: store: Object store to retrieve objects from haves: Set of commit IDs the client has want: Commit ID the client wants earliest: Earliest commit time to consider Returns: True if the want is satisfied by the haves """ o = store[want] pending = deque([o]) known = {want} while pending: commit = pending.popleft() if commit.id in haves: return True if not isinstance(commit, Commit): # non-commit wants are assumed to be satisfied continue for parent in commit.parents: if parent in known: continue known.add(parent) parent_obj = store[parent] assert isinstance(parent_obj, Commit) # TODO: handle parents with later commit times than children if parent_obj.commit_time >= earliest: pending.append(parent_obj) return False def _all_wants_satisfied( store: ObjectContainer, haves: AbstractSet[ObjectID], wants: set[ObjectID] ) -> bool: """Check whether all the current wants are satisfied by a set of haves. Args: store: Object store to retrieve objects from haves: A set of commits we know the client has. wants: A set of commits the client wants Note: Wants are specified with set_wants rather than passed in since in the current interface they are determined outside this class. """ haves = set(haves) if haves: have_objs = [store[h] for h in haves] earliest = min([h.commit_time for h in have_objs if isinstance(h, Commit)]) else: earliest = 0 for want in wants: if not _want_satisfied(store, haves, want, earliest): return False return True class AckGraphWalkerImpl: """Base class for acknowledgment graph walker implementations.""" def __init__(self, graph_walker: "_ProtocolGraphWalker") -> None: """Initialize acknowledgment graph walker. Args: graph_walker: Graph walker to wrap """ raise NotImplementedError def ack(self, have_ref: ObjectID) -> None: """Acknowledge a have reference. Args: have_ref: Object ID to acknowledge """ raise NotImplementedError def handle_done(self, done_required: bool, done_received: bool) -> bool: """Handle 'done' packet from client.""" raise NotImplementedError class _ProtocolGraphWalker: """A graph walker that knows the git protocol. As a graph walker, this class implements ack(), next(), and reset(). It also contains some base methods for interacting with the wire and walking the commit tree. The work of determining which acks to send is passed on to the implementation instance stored in _impl. The reason for this is that we do not know at object creation time what ack level the protocol requires. A call to set_ack_type() is required to set up the implementation, before any calls to next() or ack() are made. """ def __init__( self, handler: "UploadPackHandler", object_store: ObjectContainer, get_peeled: Callable[[Ref], ObjectID | None], get_symrefs: Callable[[], dict[Ref, Ref]], ) -> None: """Initialize a ProtocolGraphWalker. Args: handler: Protocol handler instance object_store: Object store for retrieving objects get_peeled: Function to get peeled refs get_symrefs: Function to get symbolic refs """ self.handler = handler self.store: ObjectContainer = object_store self.get_peeled = get_peeled self.get_symrefs = get_symrefs self.proto = handler.proto self.stateless_rpc = handler.stateless_rpc self.advertise_refs = handler.advertise_refs self._wants: list[ObjectID] = [] self.shallow: set[ObjectID] = set() self.client_shallow: set[ObjectID] = set() self.unshallow: set[ObjectID] = set() self._cached = False self._cache: list[ObjectID] = [] self._cache_index = 0 self._impl: AckGraphWalkerImpl | None = None def determine_wants( self, heads: Mapping[Ref, ObjectID], depth: int | None = None ) -> list[ObjectID]: """Determine the wants for a set of heads. The given heads are advertised to the client, who then specifies which refs they want using 'want' lines. This portion of the protocol is the same regardless of ack type, and in fact is used to set the ack type of the ProtocolGraphWalker. If the client has the 'shallow' capability, this method also reads and responds to the 'shallow' and 'deepen' lines from the client. These are not part of the wants per se, but they set up necessary state for walking the graph. Additionally, later code depends on this method consuming everything up to the first 'have' line. Args: heads: a dict of refname->SHA1 to advertise depth: Maximum depth for shallow clones Returns: a list of SHA1s requested by the client """ symrefs = self.get_symrefs() values = set(heads.values()) if self.advertise_refs or not self.stateless_rpc: for i, (ref, sha) in enumerate(sorted(heads.items())): try: peeled_sha = self.get_peeled(ref) except KeyError: # Skip refs that are inaccessible # TODO(jelmer): Integrate with Repo.find_missing_objects refs # logic. continue if i == 0: logger.info("Sending capabilities: %s", self.handler.capabilities()) line = format_ref_line( ref, sha, list(self.handler.capabilities()) + symref_capabilities(symrefs.items()), ) else: line = format_ref_line(ref, sha) self.proto.write_pkt_line(line) if peeled_sha is not None and peeled_sha != sha: self.proto.write_pkt_line( format_ref_line(ref + PEELED_TAG_SUFFIX, peeled_sha) ) # i'm done.. self.proto.write_pkt_line(None) if self.advertise_refs: return [] # Now client will sending want want want commands want = self.proto.read_pkt_line() if not want: return [] line, caps = extract_want_line_capabilities(want) self.handler.set_client_capabilities(caps) self.set_ack_type(ack_type(caps)) allowed = (COMMAND_WANT, COMMAND_SHALLOW, COMMAND_DEEPEN, COMMAND_FILTER, None) command, sha_result = _split_proto_line(line, allowed) want_revs: list[ObjectID] = [] while command == COMMAND_WANT: assert isinstance(sha_result, bytes) if sha_result not in values: raise GitProtocolError(f"Client wants invalid object {sha_result!r}") want_revs.append(ObjectID(sha_result)) command, sha_result = self.read_proto_line(allowed) self.set_wants(want_revs) # Handle filter command if present (protocol v2) if command == COMMAND_FILTER: assert isinstance(sha_result, bytes) try: self.handler.filter_spec = parse_filter_spec( sha_result, object_store=self.handler.repo.object_store ) except ValueError as e: raise GitProtocolError(f"Invalid filter specification: {e}") # Read next command after processing filter command, sha_result = self.read_proto_line(allowed) if command in (COMMAND_SHALLOW, COMMAND_DEEPEN): assert sha_result is not None self.unread_proto_line(command, sha_result) self._handle_shallow_request(want_revs) if self.stateless_rpc and self.proto.eof(): # The client may close the socket at this point, expecting a # flush-pkt from the server. We might be ready to send a packfile # at this point, so we need to explicitly short-circuit in this # case. return [] return want_revs def unread_proto_line(self, command: bytes, value: bytes | int) -> None: """Push a command back to be read again. Args: command: Command name value: Command value """ if isinstance(value, int): value = str(value).encode("ascii") self.proto.unread_pkt_line(command + b" " + value) def nak(self) -> None: """Send a NAK response.""" def ack(self, have_ref: ObjectID) -> None: """Acknowledge a have reference. Args: have_ref: SHA to acknowledge (40 bytes hex for SHA-1, 64 bytes for SHA-256) Raises: ValueError: If have_ref is not a valid length """ if len(have_ref) not in (40, 64): raise ValueError(f"invalid sha {have_ref!r}") assert self._impl is not None return self._impl.ack(have_ref) def reset(self) -> None: """Reset the graph walker cache.""" self._cached = True self._cache_index = 0 def next(self) -> ObjectID | None: """Get the next SHA from the graph walker. Returns: Next SHA or None if done """ if not self._cached: if not self._impl and self.stateless_rpc: return None assert self._impl is not None return next(self._impl) # type: ignore[call-overload, no-any-return] self._cache_index += 1 if self._cache_index > len(self._cache): return None return self._cache[self._cache_index] def __next__(self) -> ObjectID | None: return self.next() def read_proto_line( self, allowed: Iterable[bytes | None] | None ) -> tuple[bytes | None, bytes | int | None]: """Read a line from the wire. Args: allowed: An iterable of command names that should be allowed. Returns: A tuple of (command, value); see _split_proto_line. Raises: UnexpectedCommandError: If an error occurred reading the line. """ return _split_proto_line(self.proto.read_pkt_line(), allowed) def _handle_shallow_request(self, wants: Sequence[ObjectID]) -> None: """Handle shallow clone requests from the client. Args: wants: List of wanted object SHAs """ while True: command, val = self.read_proto_line((COMMAND_DEEPEN, COMMAND_SHALLOW)) if command == COMMAND_DEEPEN: assert isinstance(val, int) depth = val break assert isinstance(val, bytes) self.client_shallow.add(ObjectID(val)) self.read_proto_line((None,)) # consume client's flush-pkt shallow, not_shallow = find_shallow(self.store, wants, depth) # Update self.shallow instead of reassigning it since we passed a # reference to it before this method was called. self.shallow.update(shallow - not_shallow) new_shallow = self.shallow - self.client_shallow unshallow = self.unshallow = not_shallow & self.client_shallow self.update_shallow(new_shallow, unshallow) def update_shallow( self, new_shallow: AbstractSet[ObjectID], unshallow: AbstractSet[ObjectID] ) -> None: """Update shallow/unshallow information to the client. Args: new_shallow: Set of newly shallow commits unshallow: Set of commits to unshallow """ for sha in sorted(new_shallow): self.proto.write_pkt_line(format_shallow_line(sha)) for sha in sorted(unshallow): self.proto.write_pkt_line(format_unshallow_line(sha)) self.proto.write_pkt_line(None) def notify_done(self) -> None: """Notify that the client sent 'done'.""" # relay the message down to the handler. self.handler.notify_done() def send_ack(self, sha: ObjectID, ack_type: bytes = b"") -> None: """Send an ACK to the client. Args: sha: SHA to acknowledge ack_type: Type of ACK (e.g., b'continue', b'ready') """ self.proto.write_pkt_line(format_ack_line(sha, ack_type)) def send_nak(self) -> None: """Send a NAK to the client.""" self.proto.write_pkt_line(NAK_LINE) def handle_done(self, done_required: bool, done_received: bool) -> bool: """Handle the 'done' command. Args: done_required: Whether done is required done_received: Whether done was received Returns: True if done handling succeeded """ # Delegate this to the implementation. assert self._impl is not None return self._impl.handle_done(done_required, done_received) def set_wants(self, wants: list[ObjectID]) -> None: """Set the list of wanted objects. Args: wants: List of wanted object SHAs """ self._wants = wants def all_wants_satisfied(self, haves: AbstractSet[ObjectID]) -> bool: """Check whether all the current wants are satisfied by a set of haves. Args: haves: A set of commits we know the client has. Note: Wants are specified with set_wants rather than passed in since in the current interface they are determined outside this class. """ return _all_wants_satisfied(self.store, haves, set(self._wants)) def set_ack_type(self, ack_type: int) -> None: """Set the acknowledgment type for the graph walker. Args: ack_type: One of SINGLE_ACK, MULTI_ACK, or MULTI_ACK_DETAILED """ impl_classes: dict[int, type[AckGraphWalkerImpl]] = { MULTI_ACK: MultiAckGraphWalkerImpl, MULTI_ACK_DETAILED: MultiAckDetailedGraphWalkerImpl, SINGLE_ACK: SingleAckGraphWalkerImpl, } self._impl = impl_classes[ack_type](self) _GRAPH_WALKER_COMMANDS = (COMMAND_HAVE, COMMAND_DONE, None) class SingleAckGraphWalkerImpl(AckGraphWalkerImpl): """Graph walker implementation that speaks the single-ack protocol.""" def __init__(self, walker: "_ProtocolGraphWalker") -> None: """Initialize a SingleAckGraphWalkerImpl. Args: walker: Parent ProtocolGraphWalker instance """ self.walker = walker self._common: list[ObjectID] = [] def ack(self, have_ref: ObjectID) -> None: """Acknowledge a have reference. Args: have_ref: Object ID to acknowledge """ if not self._common: self.walker.send_ack(have_ref) self._common.append(have_ref) def next(self) -> ObjectID | None: """Get next SHA from graph walker. Returns: SHA bytes or None if done """ command, sha = self.walker.read_proto_line(_GRAPH_WALKER_COMMANDS) if command in (None, COMMAND_DONE): # defer the handling of done self.walker.notify_done() return None elif command == COMMAND_HAVE: assert isinstance(sha, bytes) return ObjectID(sha) return None __next__ = next def handle_done(self, done_required: bool, done_received: bool) -> bool: """Handle done command. Args: done_required: Whether done is required done_received: Whether done was received Returns: True if handling completed successfully """ if not self._common: self.walker.send_nak() if done_required and not done_received: # we are not done, especially when done is required; skip # the pack for this request and especially do not handle # the done. return False if not done_received and not self._common: # Okay we are not actually done then since the walker picked # up no haves. This is usually triggered when client attempts # to pull from a source that has no common base_commit. # See: test_server.MultiAckDetailedGraphWalkerImplTestCase.\ # test_multi_ack_stateless_nodone return False return True class MultiAckGraphWalkerImpl(AckGraphWalkerImpl): """Graph walker implementation that speaks the multi-ack protocol.""" def __init__(self, walker: "_ProtocolGraphWalker") -> None: """Initialize multi-ack graph walker. Args: walker: Parent ProtocolGraphWalker instance """ self.walker = walker self._found_base = False self._common: list[ObjectID] = [] def ack(self, have_ref: ObjectID) -> None: """Acknowledge a have reference. Args: have_ref: Object ID to acknowledge """ self._common.append(have_ref) if not self._found_base: self.walker.send_ack(have_ref, b"continue") if self.walker.all_wants_satisfied(set(self._common)): self._found_base = True # else we blind ack within next def next(self) -> ObjectID | None: """Get next SHA from graph walker. Returns: SHA bytes or None if done """ while True: command, sha = self.walker.read_proto_line(_GRAPH_WALKER_COMMANDS) if command is None: self.walker.send_nak() # in multi-ack mode, a flush-pkt indicates the client wants to # flush but more have lines are still coming continue elif command == COMMAND_DONE: self.walker.notify_done() return None elif command == COMMAND_HAVE: assert isinstance(sha, bytes) sha_id = ObjectID(sha) if self._found_base: # blind ack self.walker.send_ack(sha_id, b"continue") return sha_id __next__ = next def handle_done(self, done_required: bool, done_received: bool) -> bool: """Handle done command. Args: done_required: Whether done is required done_received: Whether done was received Returns: True if handling completed successfully """ if done_required and not done_received: # we are not done, especially when done is required; skip # the pack for this request and especially do not handle # the done. return False if not done_received and not self._common: # Okay we are not actually done then since the walker picked # up no haves. This is usually triggered when client attempts # to pull from a source that has no common base_commit. # See: test_server.MultiAckDetailedGraphWalkerImplTestCase.\ # test_multi_ack_stateless_nodone return False # don't nak unless no common commits were found, even if not # everything is satisfied if self._common: self.walker.send_ack(self._common[-1]) else: self.walker.send_nak() return True class MultiAckDetailedGraphWalkerImpl(AckGraphWalkerImpl): """Graph walker implementation speaking the multi-ack-detailed protocol.""" def __init__(self, walker: "_ProtocolGraphWalker") -> None: """Initialize multi-ack-detailed graph walker. Args: walker: Parent ProtocolGraphWalker instance """ self.walker = walker self._common: list[ObjectID] = [] def ack(self, have_ref: ObjectID) -> None: """Acknowledge a have reference. Args: have_ref: Object ID to acknowledge """ # Should only be called iff have_ref is common self._common.append(have_ref) self.walker.send_ack(have_ref, b"common") def next(self) -> ObjectID | None: """Get next SHA from graph walker. Returns: SHA bytes or None if done """ while True: command, sha = self.walker.read_proto_line(_GRAPH_WALKER_COMMANDS) if command is None: if self.walker.all_wants_satisfied(set(self._common)): self.walker.send_ack(self._common[-1], b"ready") self.walker.send_nak() if self.walker.stateless_rpc: # The HTTP version of this request a flush-pkt always # signifies an end of request, so we also return # nothing here as if we are done (but not really, as # it depends on whether no-done capability was # specified and that's handled in handle_done which # may or may not call post_nodone_check depending on # that). return None elif command == COMMAND_DONE: # Let the walker know that we got a done. self.walker.notify_done() break elif command == COMMAND_HAVE: # return the sha and let the caller ACK it with the # above ack method. assert isinstance(sha, bytes) return ObjectID(sha) # don't nak unless no common commits were found, even if not # everything is satisfied return None __next__ = next def handle_done(self, done_required: bool, done_received: bool) -> bool: """Handle done command. Args: done_required: Whether done is required done_received: Whether done was received Returns: True if handling completed successfully """ if done_required and not done_received: # we are not done, especially when done is required; skip # the pack for this request and especially do not handle # the done. return False if not done_received and not self._common: # Okay we are not actually done then since the walker picked # up no haves. This is usually triggered when client attempts # to pull from a source that has no common base_commit. # See: test_server.MultiAckDetailedGraphWalkerImplTestCase.\ # test_multi_ack_stateless_nodone return False # don't nak unless no common commits were found, even if not # everything is satisfied if self._common: self.walker.send_ack(self._common[-1]) else: self.walker.send_nak() return True class ReceivePackHandler(PackHandler): """Protocol handler for downloading a pack from the client.""" def __init__( self, backend: Backend, args: Sequence[str], proto: Protocol, stateless_rpc: bool = False, advertise_refs: bool = False, ) -> None: """Initialize receive-pack handler. Args: backend: Backend instance args: Command arguments proto: Protocol instance stateless_rpc: Whether to use stateless RPC advertise_refs: Whether to advertise refs """ super().__init__(backend, proto, stateless_rpc=stateless_rpc) self.repo = backend.open_repository(args[0]) self.advertise_refs = advertise_refs def capabilities(self) -> Iterable[bytes]: """Return supported capabilities. Returns: List of capability names including object-format for the repository """ return [ CAPABILITY_REPORT_STATUS, CAPABILITY_DELETE_REFS, CAPABILITY_QUIET, CAPABILITY_ATOMIC, CAPABILITY_OFS_DELTA, CAPABILITY_SIDE_BAND_64K, CAPABILITY_NO_DONE, capability_object_format(self.repo.object_format.name), ] def _receive_max_input_size(self) -> int | None: """Return the configured ``receive.maxInputSize`` for this repo. Mirrors git: the value is in bytes, and ``0`` (the default) means unlimited. Returned as ``None`` when unset or zero so it can be passed verbatim as ``add_thin_pack(..., max_input_size=...)``. """ config = self.repo.get_config_stack() # type: ignore[attr-defined] try: raw = config.get((b"receive",), b"maxInputSize") except KeyError: return None try: value = int(raw.decode()) except ValueError: logger.warning("Ignoring invalid receive.maxInputSize value %r", raw) return None return value if value > 0 else None def _apply_pack( self, refs: list[tuple[ObjectID, ObjectID, Ref]] ) -> Iterator[tuple[bytes, bytes]]: """Apply received pack to repository. Args: refs: List of (old_sha, new_sha, ref_name) tuples Yields: Tuples of (ref_name, error_message) for any errors """ all_exceptions = ( IOError, OSError, ChecksumMismatch, ApplyDeltaError, AssertionError, socket.error, zlib.error, ObjectFormatException, ) will_send_pack = False zero_sha = ObjectID(b"0" * self.repo.object_format.hex_length) for command in refs: if command[1] != zero_sha: will_send_pack = True if will_send_pack: # TODO: more informative error messages than just the exception # string try: recv = getattr(self.proto, "recv", None) self.repo.object_store.add_thin_pack( # type: ignore[attr-defined] self.proto.read, recv, max_input_size=self._receive_max_input_size(), ) yield (b"unpack", b"ok") except all_exceptions as e: yield (b"unpack", str(e).replace("\n", "").encode("utf-8")) # The pack may still have been moved in, but it may contain # broken objects. We trust a later GC to clean it up. return else: # The git protocol want to find a status entry related to unpack # process even if no pack data has been sent. yield (b"unpack", b"ok") atomic = self.has_capability(CAPABILITY_ATOMIC) if atomic: # Atomic push: validate all refs first, then apply all or none ref_results: list[tuple[Ref, bytes]] = [] has_failure = False for oldsha, sha, ref in refs: ref_status = b"ok" hook_error = self._on_update(ref, oldsha, sha) if hook_error: ref_status = hook_error has_failure = True else: try: if sha == zero_sha: if CAPABILITY_DELETE_REFS not in self.capabilities(): raise GitProtocolError( "Attempted to delete refs without " "delete-refs capability." ) except KeyError: ref_status = b"bad ref" has_failure = True ref_results.append((ref, ref_status)) if has_failure: # At least one ref failed validation; fail all refs for ref, status in ref_results: if status == b"ok": yield (ref, b"atomic push failed") else: yield (ref, status) return # All validations passed; apply all ref updates for oldsha, sha, ref in refs: ref_status = b"ok" try: if sha == zero_sha: try: self.repo.refs.remove_if_equals(ref, oldsha) except all_exceptions: ref_status = b"failed to delete" else: try: self.repo.refs.set_if_equals(ref, oldsha, sha) except all_exceptions: ref_status = b"failed to write" except KeyError: ref_status = b"bad ref" yield (ref, ref_status) else: for oldsha, sha, ref in refs: ref_status = b"ok" # Run update hook for this ref hook_error = self._on_update(ref, oldsha, sha) if hook_error: # Update hook declined this ref ref_status = hook_error yield (ref, ref_status) continue try: if sha == zero_sha: if CAPABILITY_DELETE_REFS not in self.capabilities(): raise GitProtocolError( "Attempted to delete refs without " "delete-refs capability." ) try: self.repo.refs.remove_if_equals(ref, oldsha) except all_exceptions: ref_status = b"failed to delete" else: try: self.repo.refs.set_if_equals(ref, oldsha, sha) except all_exceptions: ref_status = b"failed to write" except KeyError: ref_status = b"bad ref" yield (ref, ref_status) def _report_status(self, status: Sequence[tuple[bytes, bytes]]) -> None: """Report status to client. Args: status: List of (ref_name, status_message) tuples """ if self.has_capability(CAPABILITY_SIDE_BAND_64K): writer = BufferedPktLineWriter( lambda d: self.proto.write_sideband(SIDE_BAND_CHANNEL_DATA, d) ) write = writer.write def flush() -> None: writer.flush() self.proto.write_pkt_line(None) else: write = self.proto.write_pkt_line # type: ignore[assignment] def flush() -> None: pass for name, msg in status: if name == b"unpack": write(b"unpack " + msg + b"\n") elif msg == b"ok": write(b"ok " + name + b"\n") else: write(b"ng " + name + b" " + msg + b"\n") write(None) # type: ignore flush() def _on_pre_receive( self, client_refs: list[tuple[ObjectID, ObjectID, Ref]] ) -> None: """Run pre-receive hook. Args: client_refs: List of (old_sha, new_sha, ref_name) tuples Raises: HookError: If hook fails, preventing the push """ hook = self.repo.hooks.get("pre-receive", None) # type: ignore[attr-defined] if not hook: return try: stdout, stderr = hook.execute(client_refs) # Only send output via sideband if capabilities are set if self._client_capabilities is not None: if stdout and self.has_capability(CAPABILITY_SIDE_BAND_64K): self.proto.write_sideband(SIDE_BAND_CHANNEL_PROGRESS, stdout) if stderr and self.has_capability(CAPABILITY_SIDE_BAND_64K): self.proto.write_sideband(SIDE_BAND_CHANNEL_PROGRESS, stderr) except HookError as err: # Send error to client via sideband if available if self._client_capabilities is not None and self.has_capability( CAPABILITY_SIDE_BAND_64K ): self.proto.write_sideband( SIDE_BAND_CHANNEL_FATAL, str(err).encode("utf-8") ) # Re-raise to abort the push raise def _on_update( self, ref_name: Ref, old_sha: ObjectID, new_sha: ObjectID ) -> bytes | None: """Run update hook for a single ref. Args: ref_name: Name of the reference old_sha: Old SHA of the reference new_sha: New SHA of the reference Returns: Error message if hook fails, None otherwise """ hook = self.repo.hooks.get("update", None) # type: ignore[attr-defined] if not hook: return None try: stdout, stderr = hook.execute(ref_name, old_sha, new_sha) # Only send output via sideband if capabilities are set if self._client_capabilities is not None: if stdout and self.has_capability(CAPABILITY_SIDE_BAND_64K): self.proto.write_sideband(SIDE_BAND_CHANNEL_PROGRESS, stdout) if stderr and self.has_capability(CAPABILITY_SIDE_BAND_64K): self.proto.write_sideband(SIDE_BAND_CHANNEL_PROGRESS, stderr) return None except HookError as err: # Return error message to mark this ref as failed return str(err).encode("utf-8") def _on_post_receive(self, client_refs: dict[bytes, tuple[bytes, bytes]]) -> None: """Run post-receive hook. Args: client_refs: Dictionary of ref changes from client """ hook = self.repo.hooks.get("post-receive", None) # type: ignore[attr-defined] if not hook: return try: output = hook.execute(client_refs) if output: self.proto.write_sideband(SIDE_BAND_CHANNEL_PROGRESS, output) except HookError as err: self.proto.write_sideband(SIDE_BAND_CHANNEL_FATAL, str(err).encode("utf-8")) def handle(self) -> None: """Handle receive-pack request.""" if self.advertise_refs or not self.stateless_rpc: refs = sorted(self.repo.get_refs().items()) symrefs = sorted(self.repo.refs.get_symrefs().items()) if not refs: zero_sha = ObjectID(b"0" * self.repo.object_format.hex_length) refs = [(Ref(CAPABILITIES_REF), zero_sha)] logger.info("Sending capabilities: %s", self.capabilities()) self.proto.write_pkt_line( format_ref_line( refs[0][0], refs[0][1], list(self.capabilities()) + symref_capabilities(symrefs), ) ) for i in range(1, len(refs)): ref = refs[i] self.proto.write_pkt_line(format_ref_line(ref[0], ref[1])) self.proto.write_pkt_line(None) if self.advertise_refs: return client_refs = [] ref_line = self.proto.read_pkt_line() # if ref is none then client doesn't want to send us anything.. if ref_line is None: return ref_line, caps = extract_capabilities(ref_line) self.set_client_capabilities(caps) # client will now send us a list of (oldsha, newsha, ref) while ref_line: try: (oldsha, newsha, ref_name) = ref_line.rstrip(b"\n").split(b" ") except ValueError: raise GitProtocolError( f"Invalid ref update line from client: {ref_line!r}" ) if not valid_hexsha(oldsha) or not valid_hexsha(newsha): raise GitProtocolError( f"Invalid ref update line from client: {ref_line!r}" ) client_refs.append((ObjectID(oldsha), ObjectID(newsha), Ref(ref_name))) ref_line = self.proto.read_pkt_line() # Run pre-receive hook before processing the pack # If it fails, we abort the entire push try: self._on_pre_receive(client_refs) except HookError: # Hook failed, report error to client and abort # We still need to consume the pack data to avoid protocol errors if self.has_capability(CAPABILITY_REPORT_STATUS): # Send unpack error status status = [(b"unpack", b"pre-receive hook declined")] # Add 'ng' (not good) status for all refs for _, _, ref_name in client_refs: status.append((ref_name, b"pre-receive hook declined")) self._report_status(status) return # backend can now deal with this refs and read a pack using self.read status = list(self._apply_pack(client_refs)) self._on_post_receive(client_refs) # type: ignore[arg-type] # when we have read all the pack from the client, send a status report # if the client asked for it if self.has_capability(CAPABILITY_REPORT_STATUS): self._report_status(status) class UploadArchiveHandler(Handler): """Handler for git-upload-archive requests.""" def __init__( self, backend: Backend, args: Sequence[str], proto: Protocol, stateless_rpc: bool = False, ) -> None: """Initialize upload-archive handler. Args: backend: Backend instance args: Command arguments proto: Protocol instance stateless_rpc: Whether to use stateless RPC """ super().__init__(backend, proto, stateless_rpc) self.repo = backend.open_repository(args[0]) def handle(self) -> None: """Handle upload-archive request.""" def write(x: bytes) -> None: self.proto.write_sideband(SIDE_BAND_CHANNEL_DATA, x) arguments = [] for pkt in self.proto.read_pkt_seq(): (key, value) = pkt.split(b" ", 1) if key != b"argument": raise GitProtocolError(f"unknown command {key!r}") arguments.append(value.rstrip(b"\n")) prefix = b"" format = "tar" i = 0 store: BaseObjectStore = self.repo.object_store tree: Tree | None = None while i < len(arguments): argument = arguments[i] if argument == b"--prefix": i += 1 prefix = arguments[i] elif argument == b"--format": i += 1 format = arguments[i].decode("ascii") else: commit_sha = self.repo.refs[Ref(argument)] commit_obj = store[commit_sha] assert isinstance(commit_obj, Commit) tree_obj = store[commit_obj.tree] assert isinstance(tree_obj, Tree) tree = tree_obj i += 1 if tree is None: raise GitProtocolError("upload-archive missing tree argument") self.proto.write_pkt_line(b"ACK") self.proto.write_pkt_line(None) for chunk in tar_stream( store, tree, mtime=int(time.time()), prefix=prefix, format=format, ): write(chunk) self.proto.write_pkt_line(None) # Default handler classes for git services. DEFAULT_HANDLERS = { b"git-upload-pack": UploadPackHandler, b"git-receive-pack": ReceivePackHandler, b"git-upload-archive": UploadArchiveHandler, } class TCPGitRequestHandler(socketserver.StreamRequestHandler): """TCP request handler for git protocol.""" def __init__( self, handlers: dict[bytes, type[Handler]], request: socket.socket, client_address: tuple[str, int], server: socketserver.TCPServer, ) -> None: """Initialize TCP request handler. Args: handlers: Dictionary mapping commands to handler classes request: Request socket client_address: Client address tuple server: Server instance """ self.handlers = handlers socketserver.StreamRequestHandler.__init__( self, request, client_address, server ) def handle(self) -> None: """Handle TCP git request.""" proto = ReceivableProtocol(self.connection.recv, self.wfile.write) command, args = proto.read_cmd() logger.info("Handling %s request, args=%s", command, args) cls = self.handlers.get(command, None) if not callable(cls): raise GitProtocolError(f"Invalid service {command!r}") h = cls(self.server.backend, args, proto) # type: ignore h.handle() class TCPGitServer(socketserver.TCPServer): """TCP server for git protocol.""" allow_reuse_address = True serve = socketserver.TCPServer.serve_forever def _make_handler( self, request: socket.socket, client_address: tuple[str, int], server: socketserver.TCPServer, ) -> TCPGitRequestHandler: """Create request handler instance. Args: request: Request socket client_address: Client address tuple server: Server instance Returns: TCPGitRequestHandler instance """ return TCPGitRequestHandler(self.handlers, request, client_address, server) def __init__( self, backend: Backend, listen_addr: str, port: int = TCP_GIT_PORT, handlers: dict[bytes, type[Handler]] | None = None, ) -> None: """Initialize TCP git server. Args: backend: Backend instance listen_addr: Address to listen on port: Port to listen on (default: TCP_GIT_PORT) handlers: Optional dictionary of custom handlers """ self.handlers = dict(DEFAULT_HANDLERS) if handlers is not None: self.handlers.update(handlers) self.backend = backend logger.info("Listening for TCP connections on %s:%d", listen_addr, port) socketserver.TCPServer.__init__(self, (listen_addr, port), self._make_handler) def verify_request( self, request: socket.socket | tuple[bytes, socket.socket], client_address: tuple[str, int] | socket.socket, ) -> bool: """Verify incoming request. Args: request: Request socket client_address: Client address tuple Returns: True to accept request """ logger.info("Handling request from %s", client_address) return True def handle_error( self, request: socket.socket | tuple[bytes, socket.socket], client_address: tuple[str, int] | socket.socket, ) -> None: """Handle request processing errors. Args: request: Request socket client_address: Client address tuple """ logger.exception( "Exception happened during processing of request from %s", client_address, ) def main(argv: list[str] = sys.argv) -> None: """Entry point for starting a TCP git server.""" import optparse parser = optparse.OptionParser() parser.add_option( "-l", "--listen_address", dest="listen_address", default="localhost", help="Binding IP address.", ) parser.add_option( "-p", "--port", dest="port", type=int, default=TCP_GIT_PORT, help="Binding TCP port.", ) options, args = parser.parse_args(argv) log_utils.default_logging_config() if len(args) > 1: gitdir = args[1] else: gitdir = "." # TODO(jelmer): Support git-daemon-export-ok and --export-all. backend = FileSystemBackend(gitdir) server = TCPGitServer(backend, options.listen_address, options.port) server.serve_forever() def serve_command( handler_cls: type[Handler], argv: list[str] = sys.argv, backend: Backend | None = None, inf: IO[bytes] | None = None, outf: IO[bytes] | None = None, ) -> int: """Serve a single command. This is mostly useful for the implementation of commands used by e.g. git+ssh. Args: handler_cls: `Handler` class to use for the request argv: execv-style command-line arguments. Defaults to sys.argv. backend: `Backend` to use inf: File-like object to read from, defaults to standard input. outf: File-like object to write to, defaults to standard output. Returns: Exit code for use with sys.exit. 0 on success, 1 on failure. """ if backend is None: backend = FileSystemBackend() in_stream: IO[bytes] = inf if inf is not None else sys.stdin.buffer out_stream: IO[bytes] = outf if outf is not None else sys.stdout.buffer def send_fn(data: bytes) -> None: out_stream.write(data) out_stream.flush() proto = Protocol(in_stream.read, send_fn) handler = handler_cls(backend, argv[1:], proto) # type: ignore[arg-type] # FIXME: Catch exceptions and write a single-line summary to outf. handler.handle() return 0 def generate_info_refs(repo: "BaseRepo") -> Iterator[bytes]: """Generate an info refs file.""" refs = repo.get_refs() return write_info_refs(refs, repo.object_store) def generate_objects_info_packs(repo: "BaseRepo") -> Iterator[bytes]: """Generate an index for for packs.""" for pack in repo.object_store.packs: yield (b"P " + os.fsencode(pack.data.filename) + b"\n") def update_server_info(repo: "BaseRepo") -> None: """Generate server info for dumb file access. This generates info/refs and objects/info/packs, similar to "git update-server-info". """ repo._put_named_file( os.path.join("info", "refs"), b"".join(generate_info_refs(repo)) ) repo._put_named_file( os.path.join("objects", "info", "packs"), b"".join(generate_objects_info_packs(repo)), ) if __name__ == "__main__": main()