use ${ENV} syntax for env-vars;

only expand environment-variables of the form ${ENV}

by default, crash on startup if the old $ENV syntax is found,
explaning that the old syntax can be enabled with an option

README.md

@@ -2542,6 +2542,7 @@ buggy feature? rip it out  by setting any of the following environment variables
 | -------------------- | ------------ |
 | `PRTY_NO_CTYPES`     | do not use features from external libraries such as kernel32 |
 | `PRTY_NO_DB_LOCK`    | do not lock session/shares-databases for exclusive access |
+| `PRTY_NO_ENVEXPAND`  | do not expand environment-variables in configs and args |
 | `PRTY_NO_IFADDR`     | disable ip/nic discovery by poking into your OS with ctypes |
 | `PRTY_NO_IMPRESO`    | do not try to load js/css files using `importlib.resources` |
 | `PRTY_NO_IPV6`       | disable some ipv6 support (should not be necessary since windows 2000) |

contrib/podman-systemd/copyparty.conf

@@ -8,7 +8,7 @@
   # and copyparty replaces %Y-%m%d with Year-MonthDay, so the
   # full path will be something like /var/log/copyparty/2023-1130.txt
   # (note: enable compression by adding .xz at the end)
-  # q, lo: $LOGS_DIRECTORY/%Y-%m%d.log
+  # q, lo: ${LOGS_DIRECTORY}/%Y-%m%d.log
 
   # p: 80,443,3923   # listen on 80/443 as well (requires CAP_NET_BIND_SERVICE)
   # i: 127.0.0.1     # only allow connections from localhost (reverse-proxies)

contrib/systemd/copyparty.example.conf

@@ -16,7 +16,7 @@
   # and copyparty replaces %Y-%m%d with Year-MonthDay, so the
   # full path will be something like /var/log/copyparty/2023-1130.txt
   # (note: enable compression by adding .xz at the end)
-  q, lo: $LOGS_DIRECTORY/%Y-%m%d.log
+  q, lo: ${LOGS_DIRECTORY}/%Y-%m%d.log
 
   # enable version-checker by uncommenting one of the 'vc-url' lines below; this will
   # periodically check if your copyparty version has a known security vulnerability,

copyparty/__main__.py

@@ -65,6 +65,10 @@ from .util import (
     b64enc,
     ctypes,
     dedent,
+    expand_osenv_c,
+    expand_osenv_cs,
+    expand_osenv_noop,
+    expand_osenv_s,
     has_resource,
     load_resource,
     min_ex,
@@ -427,9 +431,22 @@ def configure_ssl_ciphers(al: argparse.Namespace) -> None:
         sys.exit(0)
 
 
+def expand_cvars(argv) -> list[str]:
+    n = 0
+    for v in argv:
+        if "=" in v:
+            a, b = v.split("=", 1)
+            v = "%s=%s" % (a, os.path.expanduser(expand_osenv_c(b)))
+        else:
+            v = os.path.expanduser(expand_osenv_c(v))
+        argv[n] = v
+        n += 1
+    return argv
+
+
 def args_from_cfg(cfg_path: str) -> list[str]:
     lines: list[str] = []
-    expand_config_file(None, lines, cfg_path, "")
+    expand_config_file(None, expand_osenv_c, lines, cfg_path, "")
     lines = upgrade_cfg_fmt(None, argparse.Namespace(vc=False), lines, "")
 
     ret: list[str] = []
@@ -453,10 +470,12 @@ def args_from_cfg(cfg_path: str) -> list[str]:
             else:
                 ret.append(prefix + k + "=" + v)
 
-    return ret
+    return expand_cvars(ret)
 
 
 def expand_cfg(argv) -> list[str]:
+    argv = expand_cvars(argv)
+
     if CFG_DEF:
         supp = args_from_cfg(CFG_DEF[0])
         argv = argv[:1] + supp + argv[1:]
@@ -1197,6 +1216,7 @@ def add_general(ap, nc, srvname):
     ap2.add_argument("--name-url", metavar="TXT", type=u, help="URL for server name hyperlink (displayed topleft in browser)")
     ap2.add_argument("--name-html", type=u, help=argparse.SUPPRESS)
     ap2.add_argument("--site", metavar="URL", type=u, default="", help="public URL to assume when creating links; example: [\033[32mhttps://example.com/\033[0m]")
+    ap2.add_argument("--env-expand", metavar="N", type=int, default=-1, help="syntax to expect for environment-variables to expand in config-files; [\033[32m0\033[0m]=disable, [\033[32m1\033[0m]=$VAR (old syntax (scary)), [\033[32m2\033[0m]=${VAR} (new syntax (recommended))")
     ap2.add_argument("--mime", metavar="EXT=MIME", type=u, action="append", help="\033[34mREPEATABLE:\033[0m map file \033[33mEXT\033[0mension to \033[33mMIME\033[0mtype, for example [\033[32mjpg=image/jpeg\033[0m]")
     ap2.add_argument("--mimes", action="store_true", help="list default mimetype mapping and exit")
     ap2.add_argument("--rmagic", action="store_true", help="do expensive analysis to improve accuracy of returned mimetypes; will make file-downloads, rss, and webdav slower (volflag=rmagic)")
@@ -2179,6 +2199,15 @@ def main(argv: Optional[list[str]] = None) -> None:
 
     quotecheck(al)
 
+    if al.env_expand == 2:
+        al.shenvexp = expand_osenv_c
+    elif al.env_expand == 1:
+        al.shenvexp = expand_osenv_s
+    elif al.env_expand == 0:
+        al.shenvexp = expand_osenv_noop
+    else:
+        al.shenvexp = expand_osenv_cs
+
     if al.chdir:
         os.chdir(al.chdir)
 

copyparty/authsrv.py

@@ -56,7 +56,7 @@ if HAVE_SQLITE3:
 if True:  # pylint: disable=using-constant-test
     from collections.abc import Iterable
 
-    from typing import Any, Generator, Optional, Sequence, Union
+    from typing import Any, Callable, Generator, Optional, Sequence, Union
 
     from .util import NamedLogger, RootLogger
 
@@ -541,13 +541,11 @@ class VFS(object):
 
         hist = flags.get("hist")
         if hist and hist != "-":
-            zs = "{}/{}".format(hist.rstrip("/"), name)
+            flags["hist"] = "%s/%s" % (hist.rstrip("/"), name)
-            flags["hist"] = os.path.expandvars(os.path.expanduser(zs))
 
         dbp = flags.get("dbpath")
         if dbp and dbp != "-":
-            zs = "{}/{}".format(dbp.rstrip("/"), name)
+            flags["dbpath"] = "%s/%s" % (dbp.rstrip("/"), name)
-            flags["dbpath"] = os.path.expandvars(os.path.expanduser(zs))
 
         return flags
 
@@ -1279,7 +1277,7 @@ class AuthSrv(object):
         daxs: dict[str, AXS],
         mflags: dict[str, dict[str, Any]],
     ) -> tuple[str, str]:
-        src = os.path.expandvars(os.path.expanduser(src))
+        src = os.path.expanduser(self.args.shenvexp(src))
         src = absreal(src)
         dst = dst.strip("/")
 
@@ -1372,7 +1370,7 @@ class AuthSrv(object):
     ) -> None:
         self.line_ctr = 0
 
-        expand_config_file(self.log, cfg_lines, fp, "")
+        expand_config_file(self.log, self.args.shenvexp, cfg_lines, fp, "")
         if self.args.vc:
             lns = ["{:4}: {}".format(n, s) for n, s in enumerate(cfg_lines, 1)]
             self.log("expanded config file (unprocessed):\n" + "\n".join(lns))
@@ -2174,7 +2172,7 @@ class AuthSrv(object):
             if vflag == "-":
                 pass
             elif vflag:
-                vflag = os.path.expandvars(os.path.expanduser(vflag))
+                vflag = os.path.expanduser(self.args.shenvexp(vflag))
                 vol.histpath = vol.dbpath = uncyg(vflag) if WINDOWS else vflag
             elif self.args.hist:
                 for nch in range(len(hid)):
@@ -2209,7 +2207,7 @@ class AuthSrv(object):
             if vflag == "-":
                 pass
             elif vflag:
-                vflag = os.path.expandvars(os.path.expanduser(vflag))
+                vflag = os.path.expanduser(self.args.shenvexp(vflag))
                 vol.dbpath = uncyg(vflag) if WINDOWS else vflag
             elif self.args.dbpath:
                 for nch in range(len(hid)):
@@ -3964,10 +3962,14 @@ def split_cfg_ln(ln: str) -> dict[str, Any]:
 
 
 def expand_config_file(
-    log: Optional["NamedLogger"], ret: list[str], fp: str, ipath: str
+    log: Optional["NamedLogger"],
+    shenvexp: "Callable[[str], str]",
+    ret: list[str],
+    fp: str,
+    ipath: str,
 ) -> None:
     """expand all % file includes"""
-    fp = absreal(fp)
+    fp = absreal(os.path.expanduser(shenvexp(fp)))
     if len(ipath.split(" -> ")) > 64:
         raise Exception("hit max depth of 64 includes")
 
@@ -3998,7 +4000,7 @@ def expand_config_file(
             if fp2 in ipath:
                 continue
 
-            expand_config_file(log, ret, fp2, ipath)
+            expand_config_file(log, shenvexp, ret, fp2, ipath)
 
         return
 
@@ -4023,7 +4025,7 @@ def expand_config_file(
                 fp2 = ln[1:].strip()
                 fp2 = os.path.join(os.path.dirname(fp), fp2)
                 ofs = len(ret)
-                expand_config_file(log, ret, fp2, ipath)
+                expand_config_file(log, shenvexp, ret, fp2, ipath)
                 for n in range(ofs, len(ret)):
                     ret[n] = pad + ret[n]
                 continue

copyparty/mtag.py

@@ -17,6 +17,7 @@ from .util import (
     FFMPEG_URL,
     REKOBO_LKEY,
     VF_CAREFUL,
+    expand_osenv_c,
     fsenc,
     gzip,
     min_ex,
@@ -86,7 +87,7 @@ class MParser(object):
 
         while True:
             try:
-                bp = os.path.expanduser(args)
+                bp = os.path.expanduser(expand_osenv_c(args))
                 if WINDOWS:
                     bp = uncyg(bp)
 

copyparty/svchub.py

@@ -1133,17 +1133,23 @@ class SvcHub(object):
         al.th_coversd_set = set(al.th_coversd)
 
         for k in "c".split(" "):
+            if self.args.env_expand in (0, 2):
+                break
+
             vl = getattr(al, k)
             if not vl:
                 continue
 
-            vl = [os.path.expandvars(os.path.expanduser(x)) for x in vl]
+            vl = [os.path.expanduser(self.args.shenvexp(x)) for x in vl]
             setattr(al, k, vl)
 
         for k in "lo hist dbpath ssl_log".split(" "):
+            if self.args.env_expand in (0, 2):
+                break
+
             vs = getattr(al, k)
             if vs:
-                vs = os.path.expandvars(os.path.expanduser(vs))
+                vs = os.path.expanduser(self.args.shenvexp(vs))
                 setattr(al, k, vs)
 
         for k in "idp_adm stats_u".split(" "):

copyparty/util.py

@@ -1562,6 +1562,43 @@ def dedent(txt: str) -> str:
     return "\n".join([ln[pad:] for ln in lns])
 
 
+def expand_osenv_noop(txt) -> str:
+    return txt
+
+
+def _expand_osenv_c(txt) -> str:
+    if "${" not in txt:
+        return txt
+    zsl = txt.split("${")
+    ret = zsl[0]
+    for v in zsl[1:]:
+        if "}" not in v:
+            raise Exception("missing '}' after %r in config-value %r" % (v, txt))
+        a, b = v.split("}", 1)
+        try:
+            ret += os.environ[a] + b
+        except:
+            raise Exception("env-var %r not defined; config-value %r" % (a, txt))
+    return ret
+
+
+if os.environ.get("PRTY_NO_ENVEXPAND"):
+    expand_osenv_c = expand_osenv_noop
+    expand_osenv_s = expand_osenv_noop
+else:
+    expand_osenv_c = _expand_osenv_c
+    expand_osenv_s = os.path.expandvars
+
+
+def expand_osenv_cs(txt) -> str:
+    a = expand_osenv_c(txt)
+    b = expand_osenv_s(txt)
+    if a == b:
+        return a
+    t = "config-value %r is using the old syntax for environment-variables; choose one of the following options:\noption 1: update the config-value to the new syntax, ${VAR} instead of $VAR or %%VAR%%\noption 2: tell copyparty to allow the old syntax with global-option --env-expand 1 (risky)\noption 3: tell copyparty to only use the new syntax (and not expand this variable) with global-option --env-expand 2\noption 4: disable all environment-variable expansions with PRTY_NO_ENVEXPAND=1 or global-option --env-expand 0"
+    raise Exception(t % (txt,))
+
+
 def rice_tid() -> str:
     tid = threading.current_thread().ident
     c = sunpack(b"B" * 5, spack(b">Q", tid)[-5:])
@@ -3847,7 +3884,7 @@ def _parsehook(
 
     argv = cmd.split(",") if "," in cmd else [cmd]
 
-    argv[0] = os.path.expandvars(os.path.expanduser(argv[0]))
+    argv[0] = os.path.expanduser(expand_osenv_c(argv[0]))
 
     return areq, chk, imp, fork, sin, jtxt, wait, sp_ka, argv
 
@@ -4190,7 +4227,7 @@ def loadpy(ap: str, hot: bool) -> Any:
     depending on what other inconveniently named files happen
     to be in the same folder
     """
-    ap = os.path.expandvars(os.path.expanduser(ap))
+    ap = os.path.expanduser(expand_osenv_c(ap))
     mdir, mfile = os.path.split(absreal(ap))
     mname = mfile.rsplit(".", 1)[0]
     sys.path.insert(0, mdir)

tests/util.py

@@ -38,7 +38,7 @@ from copyparty.broker_thr import BrokerThr
 from copyparty.ico import Ico
 from copyparty.u2idx import U2idx
 from copyparty.up2k import Up2k
-from copyparty.util import FHC, CachedDict, Garda, Unrecv
+from copyparty.util import FHC, CachedDict, Garda, Unrecv, expand_osenv_c
 
 init_E(E)
 
@@ -195,6 +195,7 @@ class Cfg(Namespace):
             du_who="all",
             dk_salt="b" * 16,
             fk_salt="a" * 16,
+            env_expand=2,
             fsnt="lin",
             grp_all="acct",
             idp_gsep=re.compile("[|:;+,]"),
@@ -217,6 +218,7 @@ class Cfg(Namespace):
             rw_edit="md",
             s_rd_sz=256 * 1024,
             s_wr_sz=256 * 1024,
+            shenvexp=expand_osenv_c,
             shr_who="auth",
             sort="href",
             srch_hits=99999,