unix-socket fixes:

* support x-forwarded-for
* option to specify socket permissions and group
* in containers, avoid collision during restart
* add --help-bind with examples

README.md

@@ -1459,7 +1459,7 @@ some reverse proxies (such as [Caddy](https://caddyserver.com/)) can automatical
 * **warning:** nginx-QUIC (HTTP/3) is still experimental and can make uploads much slower, so HTTP/1.1 is recommended for now
 * depending on server/client, HTTP/1.1 can also be 5x faster than HTTP/2
 
-for improved security (and a tiny performance boost) consider listening on a unix-socket with `-i /tmp/party.sock` instead of `-i 127.0.0.1`
+for improved security (and a 10% performance boost) consider listening on a unix-socket with `-i unix:770:www:/tmp/party.sock` (permission `770` means only members of group `www` can access it)
 
 example webserver configs:
 
@@ -1900,7 +1900,7 @@ some notes on hardening
   * cors doesn't work right otherwise
 * if you allow anonymous uploads or otherwise don't trust the contents of a volume, you can prevent XSS with volflag `nohtml`
   * this returns html documents as plaintext, and also disables markdown rendering
-* when running behind a reverse-proxy, listen on a unix-socket with `-i /tmp/party.sock` instead of `-i 127.0.0.1` for tighter access control (plus you get a tiny performance boost for free)
+* when running behind a reverse-proxy, listen on a unix-socket for tighter access control (and more performance); see [reverse-proxy](#reverse-proxy) or `--help-bind`
 
 safety profiles:
 

copyparty/__main__.py

@@ -527,6 +527,41 @@ def showlic() -> None:
 
 def get_sects():
     return [
+        [
+            "bind",
+            "configure listening",
+            dedent(
+                """
+            \033[33m-i\033[0m takes a comma-separated list of interfaces to listen on;
+            IP-addresses and/or unix-sockets (Unix Domain Sockets)
+
+            the default (\033[32m-i ::\033[0m) means all IPv4 and IPv6 addresses
+
+            \033[32m-i 0.0.0.0\033[0m    listens on all IPv4 NICs/subnets
+            \033[32m-i 127.0.0.1\033[0m  listens on IPv4 localhost only
+            \033[32m-i 127.1\033[0m      listens on IPv4 localhost only
+            \033[32m-i 127.1,192.168.123.1\033[0m = IPv4 localhost and 192.168.123.1
+
+            \033[33m-p\033[0m takes a comma-separated list of tcp ports to listen on;
+            the default is \033[32m-p 3923\033[0m but as root you can \033[32m-p 80,443,3923\033[0m
+
+            when running behind a reverse-proxy, it's recommended to
+            use unix-sockets for improved performance and security;
+
+            \033[32m-i unix:770:www:\033[33m/tmp/a.sock\033[0m listens on \033[33m/tmp/a.sock\033[0m with
+            permissions \033[33m0770\033[0m; only accessible to members of the \033[33mwww\033[0m
+            group. This is the best approach. Alternatively,
+
+            \033[32m-i unix:777:\033[33m/tmp/a.sock\033[0m sets perms \033[33m0777\033[0m so anyone can
+            access it; bad unless it's inside a restricted folder
+
+            \033[32m-i unix:\033[33m/tmp/a.sock\033[0m keeps umask-defined permissions
+            (usually \033[33m0600\033[0m) and the same user/group as copyparty
+
+            \033[33m-p\033[0m (tcp ports) is ignored for unix sockets
+            """
+            ),
+        ],
         [
             "accounts",
             "accounts and volumes",
@@ -969,8 +1004,8 @@ def add_upload(ap):
 
 def add_network(ap):
     ap2 = ap.add_argument_group('network options')
-    ap2.add_argument("-i", metavar="IP", type=u, default="::", help="ip to bind (comma-sep.) and/or [\033[32munix:/tmp/a.sock\033[0m], default: all IPv4 and IPv6")
+    ap2.add_argument("-i", metavar="IP", type=u, default="::", help="IPs and/or unix-sockets to listen on (see \033[33m--help-bind\033[0m). Default: all IPv4 and IPv6")
-    ap2.add_argument("-p", metavar="PORT", type=u, default="3923", help="ports to bind (comma/range); ignored for unix-sockets")
+    ap2.add_argument("-p", metavar="PORT", type=u, default="3923", help="ports to listen on (comma/range); ignored for unix-sockets")
     ap2.add_argument("--ll", action="store_true", help="include link-local IPv4/IPv6 in mDNS replies, even if the NIC has routable IPs (breaks some mDNS clients)")
     ap2.add_argument("--rproxy", metavar="DEPTH", type=int, default=1, help="which ip to associate clients with; [\033[32m0\033[0m]=tcp, [\033[32m1\033[0m]=origin (first x-fwd, unsafe), [\033[32m2\033[0m]=outermost-proxy, [\033[32m3\033[0m]=second-proxy, [\033[32m-1\033[0m]=closest-proxy")
     ap2.add_argument("--xff-hdr", metavar="NAME", type=u, default="x-forwarded-for", help="if reverse-proxied, which http header to read the client's real ip from")

copyparty/httpsrv.py

@@ -365,7 +365,7 @@ class HttpSrv(object):
                         cip = cip[7:]
                     addr = (cip, saddr[1])
                 else:
-                    addr = (ip, sck.fileno())
+                    addr = ("127.8.3.7", sck.fileno())
             except (OSError, socket.error) as ex:
                 if self.stopping:
                     break

copyparty/tcpsrv.py

@@ -226,10 +226,22 @@ class TcpSrv(object):
         self.log("tcpsrv", msg, c)
 
     def _listen(self, ip: str, port: int) -> None:
+        uds_perm = uds_gid = -1
         if "unix:" in ip:
             tcp = False
             ipv = socket.AF_UNIX
-            ip = ip.split("unix:")[1]
+            uds = ip.split(":")
+            ip = uds[-1]
+            if len(uds) > 2:
+                uds_perm = int(uds[1], 8)
+            if len(uds) > 3:
+                try:
+                    uds_gid = int(uds[2])
+                except:
+                    import grp
+
+                    uds_gid = grp.getgrnam(uds[2]).gr_gid
+
         elif ":" in ip:
             tcp = True
             ipv = socket.AF_INET6
@@ -265,7 +277,13 @@ class TcpSrv(object):
                     srv.bind(ip)
                 else:
                     tf = "%s.%d" % (ip, os.getpid())
+                    if os.path.exists(tf):
+                        os.unlink(tf)
                     srv.bind(tf)
+                    if uds_gid != -1:
+                        os.chown(tf, -1, uds_gid)
+                    if uds_perm != -1:
+                        os.chmod(tf, uds_perm)
                     atomic_move(self.nlog, tf, ip, VF_CAREFUL)
 
             sport = srv.getsockname()[1] if tcp else port