copyparty/copyparty/authsrv.py

502 lines
16 KiB
Python

# coding: utf-8
from __future__ import print_function, unicode_literals
import re
import os
import sys
import stat
import threading
from .__init__ import PY2, WINDOWS
from .util import IMPLICATIONS, undot, Pebkac, fsdec, fsenc, statdir, nuprint
class VFS(object):
"""single level in the virtual fs"""
def __init__(self, realpath, vpath, uread=[], uwrite=[], flags={}):
self.realpath = realpath # absolute path on host filesystem
self.vpath = vpath # absolute path in the virtual filesystem
self.uread = uread # users who can read this
self.uwrite = uwrite # users who can write this
self.flags = flags # config switches
self.nodes = {} # child nodes
self.all_vols = {vpath: self} # flattened recursive
def __repr__(self):
return "VFS({})".format(
", ".join(
"{}={!r}".format(k, self.__dict__[k])
for k in "realpath vpath uread uwrite flags".split()
)
)
def _trk(self, vol):
self.all_vols[vol.vpath] = vol
return vol
def add(self, src, dst):
"""get existing, or add new path to the vfs"""
assert not src.endswith("/") # nosec
assert not dst.endswith("/") # nosec
if "/" in dst:
# requires breadth-first population (permissions trickle down)
name, dst = dst.split("/", 1)
if name in self.nodes:
# exists; do not manipulate permissions
return self._trk(self.nodes[name].add(src, dst))
vn = VFS(
"{}/{}".format(self.realpath, name),
"{}/{}".format(self.vpath, name).lstrip("/"),
self.uread,
self.uwrite,
self.flags,
)
self._trk(vn)
self.nodes[name] = vn
return self._trk(vn.add(src, dst))
if dst in self.nodes:
# leaf exists; return as-is
return self.nodes[dst]
# leaf does not exist; create and keep permissions blank
vp = "{}/{}".format(self.vpath, dst).lstrip("/")
vn = VFS(src, vp)
self.nodes[dst] = vn
return self._trk(vn)
def _find(self, vpath):
"""return [vfs,remainder]"""
vpath = undot(vpath)
if vpath == "":
return [self, ""]
if "/" in vpath:
name, rem = vpath.split("/", 1)
else:
name = vpath
rem = ""
if name in self.nodes:
return self.nodes[name]._find(rem)
return [self, vpath]
def can_access(self, vpath, uname):
"""return [readable,writable]"""
vn, _ = self._find(vpath)
return [
uname in vn.uread or "*" in vn.uread,
uname in vn.uwrite or "*" in vn.uwrite,
]
def get(self, vpath, uname, will_read, will_write):
"""returns [vfsnode,fs_remainder] if user has the requested permissions"""
vn, rem = self._find(vpath)
if will_read and (uname not in vn.uread and "*" not in vn.uread):
raise Pebkac(403, "you don't have read-access for this location")
if will_write and (uname not in vn.uwrite and "*" not in vn.uwrite):
raise Pebkac(403, "you don't have write-access for this location")
return vn, rem
def canonical(self, rem):
"""returns the canonical path (fully-resolved absolute fs path)"""
rp = self.realpath
if rem:
rp += "/" + rem
return fsdec(os.path.realpath(fsenc(rp)))
def ls(self, rem, uname, scandir, lstat=False):
"""return user-readable [fsdir,real,virt] items at vpath"""
virt_vis = {} # nodes readable by user
abspath = self.canonical(rem)
real = list(statdir(nuprint, scandir, lstat, abspath))
real.sort()
if not rem:
for name, vn2 in sorted(self.nodes.items()):
if uname in vn2.uread or "*" in vn2.uread:
virt_vis[name] = vn2
# no vfs nodes in the list of real inodes
real = [x for x in real if x[0] not in self.nodes]
return [abspath, real, virt_vis]
def walk(self, rel, rem, uname, dots, scandir, lstat=False):
"""
recursively yields from ./rem;
rel is a unix-style user-defined vpath (not vfs-related)
"""
fsroot, vfs_ls, vfs_virt = self.ls(rem, uname, scandir, lstat)
rfiles = [x for x in vfs_ls if not stat.S_ISDIR(x[1].st_mode)]
rdirs = [x for x in vfs_ls if stat.S_ISDIR(x[1].st_mode)]
rfiles.sort()
rdirs.sort()
yield rel, fsroot, rfiles, rdirs, vfs_virt
for rdir, _ in rdirs:
if not dots and rdir.startswith("."):
continue
wrel = (rel + "/" + rdir).lstrip("/")
wrem = (rem + "/" + rdir).lstrip("/")
for x in self.walk(wrel, wrem, uname, scandir, lstat):
yield x
for n, vfs in sorted(vfs_virt.items()):
if not dots and n.startswith("."):
continue
wrel = (rel + "/" + n).lstrip("/")
for x in vfs.walk(wrel, "", uname, scandir, lstat):
yield x
def zipgen(self, vrem, flt, uname, dots, scandir):
if flt:
flt = {k: True for k in flt}
for vpath, apath, files, rd, vd in self.walk("", vrem, uname, dots, scandir):
if flt:
files = [x for x in files if x[0] in flt]
rm = [x for x in rd if x[0] not in flt]
[rd.remove(x) for x in rm]
rm = [x for x in vd.keys() if x not in flt]
[vd.pop(x) for x in rm]
flt = None
# print(repr([vpath, apath, [x[0] for x in files]]))
fnames = [n[0] for n in files]
vpaths = [vpath + "/" + n for n in fnames] if vpath else fnames
apaths = [os.path.join(apath, n) for n in fnames]
files = list(zip(vpaths, apaths, files))
if not dots:
# dotfile filtering based on vpath (intended visibility)
files = [x for x in files if "/." not in "/" + x[0]]
rm = [x for x in rd if x[0].startswith(".")]
for x in rm:
rd.remove(x)
rm = [k for k in vd.keys() if k.startswith(".")]
for x in rm:
del vd[x]
# up2k filetring based on actual abspath
files = [x for x in files if "{0}.hist{0}up2k.".format(os.sep) not in x[1]]
for f in [{"vp": v, "ap": a, "st": n[1]} for v, a, n in files]:
yield f
def user_tree(self, uname, readable=False, writable=False):
ret = []
opt1 = readable and (uname in self.uread or "*" in self.uread)
opt2 = writable and (uname in self.uwrite or "*" in self.uwrite)
if opt1 or opt2:
ret.append(self.vpath)
for _, vn in sorted(self.nodes.items()):
ret.extend(vn.user_tree(uname, readable, writable))
return ret
class AuthSrv(object):
"""verifies users against given paths"""
def __init__(self, args, log_func, warn_anonwrite=True):
self.args = args
self.log_func = log_func
self.warn_anonwrite = warn_anonwrite
if WINDOWS:
self.re_vol = re.compile(r"^([a-zA-Z]:[\\/][^:]*|[^:]*):([^:]*):(.*)$")
else:
self.re_vol = re.compile(r"^([^:]*):([^:]*):(.*)$")
self.mutex = threading.Lock()
self.reload()
def log(self, msg, c=0):
self.log_func("auth", msg, c)
def invert(self, orig):
if PY2:
return {v: k for k, v in orig.iteritems()}
else:
return {v: k for k, v in orig.items()}
def laggy_iter(self, iterable):
"""returns [value,isFinalValue]"""
it = iter(iterable)
prev = next(it)
for x in it:
yield prev, False
prev = x
yield prev, True
def _parse_config_file(self, fd, user, mread, mwrite, mflags, mount):
vol_src = None
vol_dst = None
for ln in [x.decode("utf-8").strip() for x in fd]:
if not ln and vol_src is not None:
vol_src = None
vol_dst = None
if not ln or ln.startswith("#"):
continue
if vol_src is None:
if ln.startswith("u "):
u, p = ln[2:].split(":", 1)
user[u] = p
else:
vol_src = ln
continue
if vol_src and vol_dst is None:
vol_dst = ln
if not vol_dst.startswith("/"):
raise Exception('invalid mountpoint "{}"'.format(vol_dst))
# cfg files override arguments and previous files
vol_src = fsdec(os.path.abspath(fsenc(vol_src)))
vol_dst = vol_dst.strip("/")
mount[vol_dst] = vol_src
mread[vol_dst] = []
mwrite[vol_dst] = []
mflags[vol_dst] = {}
continue
lvl, uname = ln.split(" ")
self._read_vol_str(
lvl, uname, mread[vol_dst], mwrite[vol_dst], mflags[vol_dst]
)
def _read_vol_str(self, lvl, uname, mr, mw, mf):
if lvl == "c":
cval = True
if "=" in uname:
uname, cval = uname.split("=", 1)
self._read_volflag(mf, uname, cval, False)
return
if uname == "":
uname = "*"
if lvl in "ra":
mr.append(uname)
if lvl in "wa":
mw.append(uname)
def _read_volflag(self, flags, name, value, is_list):
if name not in ["mtp"]:
flags[name] = value
return
if not is_list:
value = [value]
elif not value:
return
flags[name] = flags.get(name, []) + value
def reload(self):
"""
construct a flat list of mountpoints and usernames
first from the commandline arguments
then supplementing with config files
before finally building the VFS
"""
user = {} # username:password
mread = {} # mountpoint:[username]
mwrite = {} # mountpoint:[username]
mflags = {} # mountpoint:[flag]
mount = {} # dst:src (mountpoint:realpath)
if self.args.a:
# list of username:password
for u, p in [x.split(":", 1) for x in self.args.a]:
user[u] = p
if self.args.v:
# list of src:dst:permset:permset:...
# permset is [rwa]username or [c]flag
for v_str in self.args.v:
m = self.re_vol.match(v_str)
if not m:
raise Exception("invalid -v argument: [{}]".format(v_str))
src, dst, perms = m.groups()
# print("\n".join([src, dst, perms]))
src = fsdec(os.path.abspath(fsenc(src)))
dst = dst.strip("/")
mount[dst] = src
mread[dst] = []
mwrite[dst] = []
mflags[dst] = {}
perms = perms.split(":")
for (lvl, uname) in [[x[0], x[1:]] for x in perms]:
self._read_vol_str(lvl, uname, mread[dst], mwrite[dst], mflags[dst])
if self.args.c:
for cfg_fn in self.args.c:
with open(cfg_fn, "rb") as f:
self._parse_config_file(f, user, mread, mwrite, mflags, mount)
if not mount:
# -h says our defaults are CWD at root and read/write for everyone
vfs = VFS(os.path.abspath("."), "", ["*"], ["*"])
elif "" not in mount:
# there's volumes but no root; make root inaccessible
vfs = VFS(os.path.abspath("."), "")
vfs.flags["d2d"] = True
maxdepth = 0
for dst in sorted(mount.keys(), key=lambda x: (x.count("/"), len(x))):
depth = dst.count("/")
assert maxdepth <= depth # nosec
maxdepth = depth
if dst == "":
# rootfs was mapped; fully replaces the default CWD vfs
vfs = VFS(mount[dst], dst, mread[dst], mwrite[dst], mflags[dst])
continue
v = vfs.add(mount[dst], dst)
v.uread = mread[dst]
v.uwrite = mwrite[dst]
v.flags = mflags[dst]
missing_users = {}
for d in [mread, mwrite]:
for _, ul in d.items():
for usr in ul:
if usr != "*" and usr not in user:
missing_users[usr] = 1
if missing_users:
self.log(
"you must -a the following users: "
+ ", ".join(k for k in sorted(missing_users)),
c=1,
)
raise Exception("invalid config")
all_mte = {}
errors = False
for vol in vfs.all_vols.values():
if (self.args.e2ds and vol.uwrite) or self.args.e2dsa:
vol.flags["e2ds"] = True
if self.args.e2d or "e2ds" in vol.flags:
vol.flags["e2d"] = True
for k in ["e2t", "e2ts", "e2tsr"]:
if getattr(self.args, k):
vol.flags[k] = True
for k1, k2 in IMPLICATIONS:
if k1 in vol.flags:
vol.flags[k2] = True
# default tag-list if unset
if "mte" not in vol.flags:
vol.flags["mte"] = self.args.mte
# append parsers from argv to volume-flags
self._read_volflag(vol.flags, "mtp", self.args.mtp, True)
# d2d drops all database features for a volume
for grp, rm in [["d2d", "e2d"], ["d2t", "e2t"]]:
if not vol.flags.get(grp, False):
continue
vol.flags["d2t"] = True
vol.flags = {k: v for k, v in vol.flags.items() if not k.startswith(rm)}
# mt* needs e2t so drop those too
for grp, rm in [["e2t", "mt"]]:
if vol.flags.get(grp, False):
continue
vol.flags = {k: v for k, v in vol.flags.items() if not k.startswith(rm)}
# verify tags mentioned by -mt[mp] are used by -mte
local_mtp = {}
local_only_mtp = {}
for a in vol.flags.get("mtp", []) + vol.flags.get("mtm", []):
a = a.split("=")[0]
local_mtp[a] = True
local = True
for b in self.args.mtp or []:
b = b.split("=")[0]
if a == b:
local = False
if local:
local_only_mtp[a] = True
local_mte = {}
for a in vol.flags.get("mte", "").split(","):
local = True
all_mte[a] = True
local_mte[a] = True
for b in self.args.mte.split(","):
if not a or not b:
continue
if a == b:
local = False
for mtp in local_only_mtp.keys():
if mtp not in local_mte:
m = 'volume "/{}" defines metadata tag "{}", but doesnt use it in "-mte" (or with "cmte" in its volume-flags)'
self.log(m.format(vol.vpath, mtp), 1)
errors = True
for mtp in self.args.mtp or []:
mtp = mtp.split("=")[0]
if mtp not in all_mte:
m = 'metadata tag "{}" is defined by "-mtm" or "-mtp", but is not used by "-mte" (or by any "cmte" volume-flag)'
self.log(m.format(mtp), 1)
errors = True
if errors:
sys.exit(1)
try:
v, _ = vfs.get("/", "*", False, True)
if self.warn_anonwrite and os.getcwd() == v.realpath:
self.warn_anonwrite = False
msg = "anyone can read/write the current directory: {}"
self.log(msg.format(v.realpath), c=1)
except Pebkac:
self.warn_anonwrite = True
with self.mutex:
self.vfs = vfs
self.user = user
self.iuser = self.invert(user)
# import pprint
# pprint.pprint({"usr": user, "rd": mread, "wr": mwrite, "mnt": mount})