diff options
Diffstat (limited to 'BitTorrent/btformats.py')
| -rw-r--r-- | BitTorrent/btformats.py | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/BitTorrent/btformats.py b/BitTorrent/btformats.py new file mode 100644 index 0000000..97e62df --- /dev/null +++ b/BitTorrent/btformats.py @@ -0,0 +1,140 @@ +# The contents of this file are subject to the BitTorrent Open Source License +# Version 1.1 (the License). You may not copy or use this file, in either +# source code or executable form, except in compliance with the License. You +# may obtain a copy of the License at http://www.bittorrent.com/license/. +# +# Software distributed under the License is distributed on an AS IS basis, +# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License +# for the specific language governing rights and limitations under the +# License. + +# Written by Bram Cohen + +import re + +from BitTorrent import BTFailure + +allowed_path_re = re.compile(r'^[^/\\.~][^/\\]*$') + +ints = (long, int) + +def check_info(info, check_paths=True): + if type(info) != dict: + raise BTFailure, _("bad metainfo - not a dictionary") + pieces = info.get('pieces') + if type(pieces) != str or len(pieces) % 20 != 0: + raise BTFailure, _("bad metainfo - bad pieces key") + piecelength = info.get('piece length') + if type(piecelength) not in ints or piecelength <= 0: + raise BTFailure, _("bad metainfo - illegal piece length") + name = info.get('name') + if type(name) != str: + raise BTFailure, _("bad metainfo - bad name") + if not allowed_path_re.match(name): + raise BTFailure, _("name %s disallowed for security reasons") % name + if info.has_key('files') == info.has_key('length'): + raise BTFailure, _("single/multiple file mix") + if info.has_key('length'): + length = info.get('length') + if type(length) not in ints or length < 0: + raise BTFailure, _("bad metainfo - bad length") + else: + files = info.get('files') + if type(files) != list: + raise BTFailure, _('bad metainfo - "files" is not a list of files') + for f in files: + if type(f) != dict: + raise BTFailure, _("bad metainfo - file entry must be a dict") + length = f.get('length') + if type(length) not in ints or length < 0: + raise BTFailure, _("bad metainfo - bad length") + path = f.get('path') + if type(path) != list or path == []: + raise BTFailure, _("bad metainfo - bad path") + for p in path: + if type(p) != str: + raise BTFailure, _("bad metainfo - bad path dir") + if check_paths and not allowed_path_re.match(p): + raise BTFailure, _("path %s disallowed for security reasons") % p + f = ['/'.join(x['path']) for x in files] + f.sort() + i = iter(f) + try: + name2 = i.next() + while True: + name1 = name2 + name2 = i.next() + if name2.startswith(name1): + if name1 == name2: + raise BTFailure, _("bad metainfo - duplicate path") + elif name2[len(name1)] == '/': + raise BTFailure(_("bad metainfo - name used as both" + "file and subdirectory name")) + except StopIteration: + pass + +def check_message(message, check_paths=True): + if type(message) != dict: + raise BTFailure, _("bad metainfo - wrong object type") + check_info(message.get('info'), check_paths) + if type(message.get('announce')) != str and type(message.get('nodes')) != list: + raise BTFailure, _("bad metainfo - no announce URL string") + if message.has_key('nodes'): + check_nodes(message.get('nodes')) + +def check_nodes(nodes): + ## note, these strings need changing + for node in nodes: + if type(node) != list: + raise BTFailure, _("bad metainfo - node is not a list") + if len(node) != 2: + raise BTFailure, _("bad metainfo - node list must have only two elements") + host, port = node + if type(host) != str: + raise BTFailure, _("bad metainfo - node host must be a string") + if type(port) != int: + raise BTFailure, _("bad metainfo - node port must be an integer") + +def check_peers(message): + if type(message) != dict: + raise BTFailure + if message.has_key('failure reason'): + if type(message['failure reason']) != str: + raise BTFailure, _("failure reason must be a string") + return + if message.has_key('warning message'): + if type(message['warning message']) != str: + raise BTFailure, _("warning message must be a string") + peers = message.get('peers') + if type(peers) == list: + for p in peers: + if type(p) != dict: + raise BTFailure, _("invalid entry in peer list - peer info must be a dict") + if type(p.get('ip')) != str: + raise BTFailure, _("invalid entry in peer list - peer ip must be a string") + port = p.get('port') + if type(port) not in ints or p <= 0: + raise BTFailure, _("invalid entry in peer list - peer port must be an integer") + if p.has_key('peer id'): + peerid = p.get('peer id') + if type(peerid) != str or len(peerid) != 20: + raise BTFailure, _("invalid entry in peer list - invalid peerid") + elif type(peers) != str or len(peers) % 6 != 0: + raise BTFailure, _("invalid peer list") + interval = message.get('interval', 1) + if type(interval) not in ints or interval <= 0: + raise BTFailure, _("invalid announce interval") + minint = message.get('min interval', 1) + if type(minint) not in ints or minint <= 0: + raise BTFailure, _("invalid min announce interval") + if type(message.get('tracker id', '')) != str: + raise BTFailure, _("invalid tracker id") + npeers = message.get('num peers', 0) + if type(npeers) not in ints or npeers < 0: + raise BTFailure, _("invalid peer count") + dpeers = message.get('done peers', 0) + if type(dpeers) not in ints or dpeers < 0: + raise BTFailure, _("invalid seed count") + last = message.get('last', 0) + if type(last) not in ints or last < 0: + raise BTFailure, _('invalid "last" entry') |