diff --git a/README.md b/README.md
index c8520202..16bfb15f 100644
--- a/README.md
+++ b/README.md
@@ -513,6 +513,8 @@ examples:
   * replacing the `g` permission with `wg` would let anonymous users upload files, but not see the required filekey to access it
   * replacing the `g` permission with `wG` would let anonymous users upload files, receiving a working direct link in return
 
+if you want to grant access to all users who are logged in, the group `acct` will always contain all known users, so for example `-v /mnt/music:music:r,@acct`
+
 anyone trying to bruteforce a password gets banned according to `--ban-pw`; default is 24h ban for 9 failed attempts in 1 hour
 
 and if you want to use config files instead of commandline args (good!) then here's the same examples as a configfile; save it as `foobar.conf` and use it like this: `python copyparty-sfx.py -c foobar.conf`
@@ -538,6 +540,7 @@ and if you want to use config files instead of commandline args (good!) then her
   accs:
     r: u1, u2  # only these accounts can read,
     r: @g1     # (exactly the same, just with a group instead)
+    r: @acct   # (alternatively, ALL users who are logged in)
     rw: u3     # and only u3 can read-write
 
 [/inc]
diff --git a/copyparty/__main__.py b/copyparty/__main__.py
index 22e219a7..38f786d8 100644
--- a/copyparty/__main__.py
+++ b/copyparty/__main__.py
@@ -609,6 +609,9 @@ def get_sects():
             if no accounts or volumes are configured,
             current folder will be read/write for everyone
 
+            the group @acct will always have every user with an account
+            (the name of that group can be changed with --grp-all)
+
             consider the config file for more flexible account/volume management,
             including dynamic reload at runtime (and being more readable w)
             """
@@ -1163,6 +1166,7 @@ def add_auth(ap):
     ap2.add_argument("--ses-db", metavar="PATH", type=u, default=ses_db, help="where to store the sessions database (if you run multiple copyparty instances, make sure they use different DBs)")
     ap2.add_argument("--ses-len", metavar="CHARS", type=int, default=20, help="session key length; default is 120 bits ((20//4)*4*6)")
     ap2.add_argument("--no-ses", action="store_true", help="disable sessions; use plaintext passwords in cookies")
+    ap2.add_argument("--grp-all", metavar="NAME", type=u, default="acct", help="the name of the auto-generated group which contains every username which is known")
     ap2.add_argument("--ipu", metavar="CIDR=USR", type=u, action="append", help="\033[34mREPEATABLE:\033[0m users with IP matching \033[33mCIDR\033[0m are auto-authenticated as username \033[33mUSR\033[0m; example: [\033[32m172.16.24.0/24=dave]")
 
 
diff --git a/copyparty/authsrv.py b/copyparty/authsrv.py
index 0f1c94f9..3bea55c8 100644
--- a/copyparty/authsrv.py
+++ b/copyparty/authsrv.py
@@ -1099,6 +1099,9 @@ class AuthSrv(object):
             if rejected:
                 continue
 
+            if gn == self.args.grp_all:
+                gn = ""
+
             # if ap/vp has a user/group placeholder, make sure to keep
             # track so the same user/group is mapped when setting perms;
             # otherwise clear un/gn to indicate it's a regular volume
@@ -1208,6 +1211,7 @@ class AuthSrv(object):
         self.load_idp_db(bool(self.idp_accs))
         ret = {un: gns[:] for un, gns in self.idp_accs.items()}
         ret.update({zs: [""] for zs in acct if zs not in ret})
+        grps[self.args.grp_all] = list(ret.keys())
         for gn, uns in grps.items():
             for un in uns:
                 try:
diff --git a/tests/util.py b/tests/util.py
index bbd0b215..16c75e92 100644
--- a/tests/util.py
+++ b/tests/util.py
@@ -185,9 +185,12 @@ class Cfg(Namespace):
             E=E,
             bup_ck="sha512",
             chmod_d="755",
+            cookie_cmax=8192,
+            cookie_nmax=50,
             dbd="wal",
             dk_salt="b" * 16,
             fk_salt="a" * 16,
+            grp_all="acct",
             idp_gsep=re.compile("[|:;+,]"),
             iobuf=256 * 1024,
             lang="eng",