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From 33b851f0c30e47fe71a293e2c990ef26573efe86 Mon Sep 17 00:00:00 2001
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From: Lennart Poettering <lennart@poettering.net>
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Date: Sat, 4 Apr 2020 12:23:02 +0200
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Subject: [PATCH] user-util: rework how we validate user names
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MIME-Version: 1.0
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Content-Type: text/plain; charset=UTF-8
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Content-Transfer-Encoding: 8bit
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This reworks the user validation infrastructure. There are now two
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modes. In regular mode we are strict and test against a strict set of
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valid chars. And in "relaxed" mode we just filter out some really
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obvious, dangerous stuff. i.e. strict is whitelisting what is OK, but
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"relaxed" is blacklisting what is really not OK.
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The idea is that we use strict mode whenver we allocate a new user
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(i.e. in sysusers.d or homed), while "relaxed" mode is when we process
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users registered elsewhere, (i.e. userdb, logind, …)
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The requirements on user name validity vary wildly. SSSD thinks its fine
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to embedd "@" for example, while the suggested NAME_REGEX field on
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Debian does not even allow uppercase chars…
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This effectively liberaralizes a lot what we expect from usernames.
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The code that warns about questionnable user names is now optional and
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only used at places such as unit file parsing, so that it doesn't show
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up on every userdb query, but only when processing configuration files
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that know better.
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Fixes: #15149 #15090
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(cherry picked from commit 7a8867abfab10e5bbca10590ec2aa40c5b27d8fb)
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Resolves: #1848373
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---
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 src/basic/user-util.c         | 185 +++++++++++++----------
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 src/basic/user-util.h         |  21 +--
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 src/core/dbus-execute.c       |   6 +-
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 src/core/dbus-manager.c       |   2 +-
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 src/core/dbus-socket.c        |   4 +-
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 src/core/dbus-util.c          |   7 +-
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 src/core/dbus-util.h          |   2 +-
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 src/core/dynamic-user.c       |   2 +-
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 src/core/load-fragment.c      |   4 +-
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 src/core/unit.c               |   2 +-
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 src/nss-systemd/nss-systemd.c |   6 +-
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 src/systemd/sd-messages.h     |   3 +
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 src/sysusers/sysusers.c       |   4 +-
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 src/test/test-user-util.c     | 271 ++++++++++++++++++----------------
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 14 files changed, 287 insertions(+), 232 deletions(-)
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diff --git a/src/basic/user-util.c b/src/basic/user-util.c
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index 68a924770b..cd870c4361 100644
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--- a/src/basic/user-util.c
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+++ b/src/basic/user-util.c
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@@ -14,6 +14,8 @@
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 #include <unistd.h>
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 #include <utmp.h>
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+#include "sd-messages.h"
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+
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 #include "alloc-util.h"
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 #include "fd-util.h"
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 #include "fileio.h"
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@@ -576,92 +578,125 @@ int take_etc_passwd_lock(const char *root) {
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         return fd;
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 }
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-bool valid_user_group_name_full(const char *u, bool strict) {
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+bool valid_user_group_name(const char *u, ValidUserFlags flags) {
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         const char *i;
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-        long sz;
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-        bool warned = false;
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-        /* Checks if the specified name is a valid user/group name. Also see POSIX IEEE Std 1003.1-2008, 2016 Edition,
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-         * 3.437. We are a bit stricter here however. Specifically we deviate from POSIX rules:
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-         *
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-         * - We require that names fit into the appropriate utmp field
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-         * - We don't allow empty user names
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-         * - No dots in the first character
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+        /* Checks if the specified name is a valid user/group name. There are two flavours of this call:
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+         * strict mode is the default which is POSIX plus some extra rules; and relaxed mode where we accept
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+         * pretty much everything except the really worst offending names.
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          *
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-         * If strict==true, additionally:
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-         * - We don't allow any dots (this conflicts with chown syntax which permits dots as user/group name separator)
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-         * - We don't allow a digit as the first character
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-         *
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-         * Note that other systems are even more restrictive, and don't permit underscores or uppercase characters.
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-         */
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+         * Whenever we synthesize users ourselves we should use the strict mode. But when we process users
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+         * created by other stuff, let's be more liberal. */
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-        if (isempty(u))
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+        if (isempty(u)) /* An empty user name is never valid */
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                 return false;
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-        if (!(u[0] >= 'a' && u[0] <= 'z') &&
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-            !(u[0] >= 'A' && u[0] <= 'Z') &&
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-            !(u[0] >= '0' && u[0] <= '9' && !strict) &&
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-            u[0] != '_')
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-                return false;
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-
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-        bool only_digits_seen = u[0] >= '0' && u[0] <= '9';
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-
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-        if (only_digits_seen) {
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-                log_warning("User or group name \"%s\" starts with a digit, accepting for compatibility.", u);
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-                warned = true;
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-        }
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-
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-        for (i = u+1; *i; i++) {
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-                if (((*i >= 'a' && *i <= 'z') ||
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-                     (*i >= 'A' && *i <= 'Z') ||
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-                     (*i >= '0' && *i <= '9') ||
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-                     IN_SET(*i, '_', '-'))) {
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-                        if (!(*i >= '0' && *i <= '9'))
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-                                only_digits_seen = false;
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-                        continue;
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-                        }
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-
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-                if (*i == '.' && !strict) {
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-                        if (!warned) {
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-                                log_warning("Bad user or group name \"%s\", accepting for compatibility.", u);
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-                                warned = true;
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-                        }
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-
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-                        continue;
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-                }
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-
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-                return false;
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+        if (parse_uid(u, NULL) >= 0) /* Something that parses as numeric UID string is valid exactly when the
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+                                      * flag for it is set */
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+                return FLAGS_SET(flags, VALID_USER_ALLOW_NUMERIC);
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+
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+        if (FLAGS_SET(flags, VALID_USER_RELAX)) {
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+
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+                /* In relaxed mode we just check very superficially. Apparently SSSD and other stuff is
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+                 * extremely liberal (way too liberal if you ask me, even inserting "@" in user names, which
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+                 * is bound to cause problems for example when used with an MTA), hence only filter the most
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+                 * obvious cases, or where things would result in an invalid entry if such a user name would
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+                 * show up in /etc/passwd (or equivalent getent output).
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+                 *
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+                 * Note that we stepped far out of POSIX territory here. It's not our fault though, but
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+                 * SSSD's, Samba's and everybody else who ignored POSIX on this. (I mean, I am happy to step
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+                 * outside of POSIX' bounds any day, but I must say in this case I probably wouldn't
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+                 * have...) */
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+
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+                if (startswith(u, " ") || endswith(u, " ")) /* At least expect whitespace padding is removed
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+                                                             * at front and back (accept in the middle, since
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+                                                             * that's apparently a thing on Windows). Note
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+                                                             * that this also blocks usernames consisting of
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+                                                             * whitespace only. */
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+                        return false;
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+
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+                if (!utf8_is_valid(u)) /* We want to synthesize JSON from this, hence insist on UTF-8 */
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+                        return false;
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+
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+                if (string_has_cc(u, NULL)) /* CC characters are just dangerous (and \n in particular is the
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+                                             * record separator in /etc/passwd), so we can't allow that. */
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+                        return false;
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+
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+                if (strpbrk(u, ":/")) /* Colons are the field separator in /etc/passwd, we can't allow
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+                                       * that. Slashes are special to file systems paths and user names
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+                                       * typically show up in the file system as home directories, hence
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+                                       * don't allow slashes. */
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+                        return false;
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+
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+                if (in_charset(u, "0123456789")) /* Don't allow fully numeric strings, they might be confused
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+                                                  * with with UIDs (note that this test is more broad than
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+                                                  * the parse_uid() test above, as it will cover more than
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+                                                  * the 32bit range, and it will detect 65535 (which is in
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+                                                  * invalid UID, even though in the unsigned 32 bit range) */
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+                        return false;
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+
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+                if (u[0] == '-' && in_charset(u + 1, "0123456789")) /* Don't allow negative fully numeric
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+                                                                     * strings either. After all some people
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+                                                                     * write 65535 as -1 (even though that's
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+                                                                     * not even true on 32bit uid_t
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+                                                                     * anyway) */
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+                        return false;
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+
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+                if (dot_or_dot_dot(u)) /* User names typically become home directory names, and these two are
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+                                        * special in that context, don't allow that. */
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+                        return false;
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+
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+                /* Compare with strict result and warn if result doesn't match */
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+                if (FLAGS_SET(flags, VALID_USER_WARN) && !valid_user_group_name(u, 0))
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+                        log_struct(LOG_NOTICE,
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+                                   "MESSAGE=Accepting user/group name '%s', which does not match strict user/group name rules.", u,
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+                                   "USER_GROUP_NAME=%s", u,
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+                                   "MESSAGE_ID=" SD_MESSAGE_UNSAFE_USER_NAME_STR);
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+
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+                /* Note that we make no restrictions on the length in relaxed mode! */
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+        } else {
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+                long sz;
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+                size_t l;
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+
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+                /* Also see POSIX IEEE Std 1003.1-2008, 2016 Edition, 3.437. We are a bit stricter here
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+                 * however. Specifically we deviate from POSIX rules:
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+                 *
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+                 * - We don't allow empty user names (see above)
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+                 * - We require that names fit into the appropriate utmp field
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+                 * - We don't allow any dots (this conflicts with chown syntax which permits dots as user/group name separator)
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+                 * - We don't allow dashes or digit as the first character
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+                 *
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+                 * Note that other systems are even more restrictive, and don't permit underscores or uppercase characters.
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+                 */
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+
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+                if (!(u[0] >= 'a' && u[0] <= 'z') &&
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+                    !(u[0] >= 'A' && u[0] <= 'Z') &&
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+                    u[0] != '_')
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+                        return false;
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+
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+                for (i = u+1; *i; i++)
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+                        if (!(*i >= 'a' && *i <= 'z') &&
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+                            !(*i >= 'A' && *i <= 'Z') &&
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+                            !(*i >= '0' && *i <= '9') &&
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+                            !IN_SET(*i, '_', '-'))
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+                                return false;
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+
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+                l = i - u;
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+
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+                sz = sysconf(_SC_LOGIN_NAME_MAX);
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+                assert_se(sz > 0);
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+
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+                if (l > (size_t) sz)
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+                        return false;
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+                if (l > FILENAME_MAX)
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+                        return false;
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+                if (l > UT_NAMESIZE - 1)
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+                        return false;
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         }
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-        if (only_digits_seen)
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-                return false;
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-
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-        sz = sysconf(_SC_LOGIN_NAME_MAX);
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-        assert_se(sz > 0);
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-
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-        if ((size_t) (i-u) > (size_t) sz)
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-                return false;
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-
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-        if ((size_t) (i-u) > UT_NAMESIZE - 1)
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-                return false;
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-
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         return true;
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 }
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-bool valid_user_group_name_or_id_full(const char *u, bool strict) {
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-
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-        /* Similar as above, but is also fine with numeric UID/GID specifications, as long as they are in the
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-         * right range, and not the invalid user ids. */
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-
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-        if (isempty(u))
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-                return false;
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-
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-        if (parse_uid(u, NULL) >= 0)
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-                return true;
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-
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-        return valid_user_group_name_full(u, strict);
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-}
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-
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 bool valid_gecos(const char *d) {
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         if (!d)
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diff --git a/src/basic/user-util.h b/src/basic/user-util.h
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index 5ad0b2a2f9..939bded40d 100644
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--- a/src/basic/user-util.h
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+++ b/src/basic/user-util.h
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@@ -78,20 +78,13 @@ static inline bool userns_supported(void) {
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         return access("/proc/self/uid_map", F_OK) >= 0;
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 }
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-bool valid_user_group_name_full(const char *u, bool strict);
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-bool valid_user_group_name_or_id_full(const char *u, bool strict);
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-static inline bool valid_user_group_name(const char *u) {
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-        return valid_user_group_name_full(u, true);
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-}
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-static inline bool valid_user_group_name_or_id(const char *u) {
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-        return valid_user_group_name_or_id_full(u, true);
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-}
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-static inline bool valid_user_group_name_compat(const char *u) {
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-        return valid_user_group_name_full(u, false);
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-}
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-static inline bool valid_user_group_name_or_id_compat(const char *u) {
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-        return valid_user_group_name_or_id_full(u, false);
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-}
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+typedef enum ValidUserFlags {
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+        VALID_USER_RELAX         = 1 << 0,
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+        VALID_USER_WARN          = 1 << 1,
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+        VALID_USER_ALLOW_NUMERIC = 1 << 2,
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+} ValidUserFlags;
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+
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+bool valid_user_group_name(const char *u, ValidUserFlags flags);
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 bool valid_gecos(const char *d);
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 bool valid_home(const char *p);
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diff --git a/src/core/dbus-execute.c b/src/core/dbus-execute.c
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index e004fb55c9..8348663000 100644
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--- a/src/core/dbus-execute.c
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+++ b/src/core/dbus-execute.c
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@@ -1113,10 +1113,10 @@ int bus_exec_context_set_transient_property(
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         flags |= UNIT_PRIVATE;
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         if (streq(name, "User"))
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-                return bus_set_transient_user_compat(u, name, &c->user, message, flags, error);
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+                return bus_set_transient_user_relaxed(u, name, &c->user, message, flags, error);
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         if (streq(name, "Group"))
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-                return bus_set_transient_user_compat(u, name, &c->group, message, flags, error);
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+                return bus_set_transient_user_relaxed(u, name, &c->group, message, flags, error);
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         if (streq(name, "TTYPath"))
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                 return bus_set_transient_path(u, name, &c->tty_path, message, flags, error);
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@@ -1298,7 +1298,7 @@ int bus_exec_context_set_transient_property(
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                         return r;
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                 STRV_FOREACH(p, l)
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-                        if (!isempty(*p) && !valid_user_group_name_or_id_compat(*p))
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+                        if (!isempty(*p) && !valid_user_group_name(*p, VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX|VALID_USER_WARN))
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                                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS,
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                                                          "Invalid supplementary group names");
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diff --git a/src/core/dbus-manager.c b/src/core/dbus-manager.c
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index 0a1d3df42f..7488f22116 100644
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--- a/src/core/dbus-manager.c
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+++ b/src/core/dbus-manager.c
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@@ -1762,7 +1762,7 @@ static int method_lookup_dynamic_user_by_name(sd_bus_message *message, void *use
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         if (!MANAGER_IS_SYSTEM(m))
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                 return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "Dynamic users are only supported in the system instance.");
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-        if (!valid_user_group_name(name))
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+        if (!valid_user_group_name(name, VALID_USER_RELAX))
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                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "User name invalid: %s", name);
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         r = dynamic_user_lookup_name(m, name, &uid);
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diff --git a/src/core/dbus-socket.c b/src/core/dbus-socket.c
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index 8fdbc05409..fa6bbe2c6f 100644
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--- a/src/core/dbus-socket.c
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+++ b/src/core/dbus-socket.c
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@@ -281,10 +281,10 @@ static int bus_socket_set_transient_property(
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                 return bus_set_transient_fdname(u, name, &s->fdname, message, flags, error);
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         if (streq(name, "SocketUser"))
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-                return bus_set_transient_user_compat(u, name, &s->user, message, flags, error);
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+                return bus_set_transient_user_relaxed(u, name, &s->user, message, flags, error);
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         if (streq(name, "SocketGroup"))
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-                return bus_set_transient_user_compat(u, name, &s->group, message, flags, error);
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+                return bus_set_transient_user_relaxed(u, name, &s->group, message, flags, error);
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         if (streq(name, "BindIPv6Only"))
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                 return bus_set_transient_bind_ipv6_only(u, name, &s->bind_ipv6_only, message, flags, error);
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diff --git a/src/core/dbus-util.c b/src/core/dbus-util.c
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index 7862beaacb..951450e53d 100644
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--- a/src/core/dbus-util.c
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+++ b/src/core/dbus-util.c
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@@ -30,7 +30,12 @@ int bus_property_get_triggered_unit(
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 BUS_DEFINE_SET_TRANSIENT(mode_t, "u", uint32_t, mode_t, "%040o");
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 BUS_DEFINE_SET_TRANSIENT(unsigned, "u", uint32_t, unsigned, "%" PRIu32);
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-BUS_DEFINE_SET_TRANSIENT_STRING_WITH_CHECK(user_compat, valid_user_group_name_or_id_compat);
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+
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+static inline bool valid_user_group_name_or_id_relaxed(const char *u) {
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+        return valid_user_group_name(u, VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX);
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+}
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+
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+BUS_DEFINE_SET_TRANSIENT_STRING_WITH_CHECK(user_relaxed, valid_user_group_name_or_id_relaxed);
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 BUS_DEFINE_SET_TRANSIENT_STRING_WITH_CHECK(path, path_is_absolute);
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 int bus_set_transient_string(
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diff --git a/src/core/dbus-util.h b/src/core/dbus-util.h
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index a3316c6701..713b464dd9 100644
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--- a/src/core/dbus-util.h
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+++ b/src/core/dbus-util.h
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@@ -235,7 +235,7 @@ int bus_property_get_triggered_unit(sd_bus *bus, const char *path, const char *i
21255d
 
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 int bus_set_transient_mode_t(Unit *u, const char *name, mode_t *p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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 int bus_set_transient_unsigned(Unit *u, const char *name, unsigned *p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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-int bus_set_transient_user_compat(Unit *u, const char *name, char **p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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+int bus_set_transient_user_relaxed(Unit *u, const char *name, char **p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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 int bus_set_transient_path(Unit *u, const char *name, char **p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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 int bus_set_transient_string(Unit *u, const char *name, char **p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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 int bus_set_transient_bool(Unit *u, const char *name, bool *p, sd_bus_message *message, UnitWriteFlags flags, sd_bus_error *error);
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diff --git a/src/core/dynamic-user.c b/src/core/dynamic-user.c
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index 021fd93a76..548b3cc9df 100644
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--- a/src/core/dynamic-user.c
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+++ b/src/core/dynamic-user.c
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@@ -108,7 +108,7 @@ static int dynamic_user_acquire(Manager *m, const char *name, DynamicUser** ret)
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                 return 0;
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         }
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-        if (!valid_user_group_name_or_id(name))
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+        if (!valid_user_group_name(name, VALID_USER_ALLOW_NUMERIC))
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                 return -EINVAL;
21255d
 
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         if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0, storage_socket) < 0)
21255d
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
21255d
index ba81d94504..e0d7b8f7f8 100644
21255d
--- a/src/core/load-fragment.c
21255d
+++ b/src/core/load-fragment.c
21255d
@@ -1932,7 +1932,7 @@ int config_parse_user_group_compat(
21255d
                 return -ENOEXEC;
21255d
         }
21255d
 
21255d
-        if (!valid_user_group_name_or_id_compat(k)) {
21255d
+        if (!valid_user_group_name(k, VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX|VALID_USER_WARN)) {
21255d
                 log_syntax(unit, LOG_ERR, filename, line, 0, "Invalid user/group name or numeric ID: %s", k);
21255d
                 return -ENOEXEC;
21255d
         }
21255d
@@ -1986,7 +1986,7 @@ int config_parse_user_group_strv_compat(
21255d
                         return -ENOEXEC;
21255d
                 }
21255d
 
21255d
-                if (!valid_user_group_name_or_id_compat(k)) {
21255d
+                if (!valid_user_group_name(k, VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX|VALID_USER_WARN)) {
21255d
                         log_syntax(unit, LOG_ERR, filename, line, 0, "Invalid user/group name or numeric ID: %s", k);
21255d
                         return -ENOEXEC;
21255d
                 }
21255d
diff --git a/src/core/unit.c b/src/core/unit.c
21255d
index ffbf3cfd48..cd3e7c806d 100644
21255d
--- a/src/core/unit.c
21255d
+++ b/src/core/unit.c
21255d
@@ -4088,7 +4088,7 @@ static int user_from_unit_name(Unit *u, char **ret) {
21255d
         if (r < 0)
21255d
                 return r;
21255d
 
21255d
-        if (valid_user_group_name(n)) {
21255d
+        if (valid_user_group_name(n, 0)) {
21255d
                 *ret = TAKE_PTR(n);
21255d
                 return 0;
21255d
         }
21255d
diff --git a/src/nss-systemd/nss-systemd.c b/src/nss-systemd/nss-systemd.c
21255d
index f8db27ae27..615c710257 100644
21255d
--- a/src/nss-systemd/nss-systemd.c
21255d
+++ b/src/nss-systemd/nss-systemd.c
21255d
@@ -123,7 +123,7 @@ static int direct_lookup_uid(uid_t uid, char **ret) {
21255d
         r = readlink_malloc(path, &s);
21255d
         if (r < 0)
21255d
                 return r;
21255d
-        if (!valid_user_group_name(s)) { /* extra safety check */
21255d
+        if (!valid_user_group_name(s, VALID_USER_RELAX)) { /* extra safety check */
21255d
                 free(s);
21255d
                 return -EINVAL;
21255d
         }
21255d
@@ -153,7 +153,7 @@ enum nss_status _nss_systemd_getpwnam_r(
21255d
 
21255d
         /* If the username is not valid, then we don't know it. Ideally libc would filter these for us anyway. We don't
21255d
          * generate EINVAL here, because it isn't really out business to complain about invalid user names. */
21255d
-        if (!valid_user_group_name(name))
21255d
+        if (!valid_user_group_name(name, VALID_USER_RELAX))
21255d
                 return NSS_STATUS_NOTFOUND;
21255d
 
21255d
         /* Synthesize entries for the root and nobody users, in case they are missing in /etc/passwd */
21255d
@@ -356,7 +356,7 @@ enum nss_status _nss_systemd_getgrnam_r(
21255d
         assert(name);
21255d
         assert(gr);
21255d
 
21255d
-        if (!valid_user_group_name(name))
21255d
+        if (!valid_user_group_name(name, VALID_USER_RELAX))
21255d
                 return NSS_STATUS_NOTFOUND;
21255d
 
21255d
         /* Synthesize records for root and nobody, in case they are missing form /etc/group */
21255d
diff --git a/src/systemd/sd-messages.h b/src/systemd/sd-messages.h
21255d
index bdd4fd3974..847b698ba4 100644
21255d
--- a/src/systemd/sd-messages.h
21255d
+++ b/src/systemd/sd-messages.h
21255d
@@ -152,6 +152,9 @@ _SD_BEGIN_DECLARATIONS;
21255d
 #define SD_MESSAGE_DNSSEC_DOWNGRADE       SD_ID128_MAKE(36,db,2d,fa,5a,90,45,e1,bd,4a,f5,f9,3e,1c,f0,57)
21255d
 #define SD_MESSAGE_DNSSEC_DOWNGRADE_STR   SD_ID128_MAKE_STR(36,db,2d,fa,5a,90,45,e1,bd,4a,f5,f9,3e,1c,f0,57)
21255d
 
21255d
+#define SD_MESSAGE_UNSAFE_USER_NAME       SD_ID128_MAKE(b6,1f,da,c6,12,e9,4b,91,82,28,5b,99,88,43,06,1f)
21255d
+#define SD_MESSAGE_UNSAFE_USER_NAME_STR   SD_ID128_MAKE_STR(b6,1f,da,c6,12,e9,4b,91,82,28,5b,99,88,43,06,1f)
21255d
+
21255d
 _SD_END_DECLARATIONS;
21255d
 
21255d
 #endif
21255d
diff --git a/src/sysusers/sysusers.c b/src/sysusers/sysusers.c
21255d
index 33959d3c11..a374ebaaf4 100644
21255d
--- a/src/sysusers/sysusers.c
21255d
+++ b/src/sysusers/sysusers.c
21255d
@@ -1413,7 +1413,7 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
21255d
                         return r;
21255d
                 }
21255d
 
21255d
-                if (!valid_user_group_name(resolved_name)) {
21255d
+                if (!valid_user_group_name(resolved_name, 0)) {
21255d
                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_name);
21255d
                         return -EINVAL;
21255d
                 }
21255d
@@ -1524,7 +1524,7 @@ static int parse_line(const char *fname, unsigned line, const char *buffer) {
21255d
                         return -EINVAL;
21255d
                 }
21255d
 
21255d
-                if (!valid_user_group_name(resolved_id)) {
21255d
+                if (!valid_user_group_name(resolved_id, 0)) {
21255d
                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_id);
21255d
                         return -EINVAL;
21255d
                 }
21255d
diff --git a/src/test/test-user-util.c b/src/test/test-user-util.c
21255d
index 56079f1486..31ac018da9 100644
21255d
--- a/src/test/test-user-util.c
21255d
+++ b/src/test/test-user-util.c
21255d
@@ -131,144 +131,163 @@ static void test_uid_ptr(void) {
21255d
         assert_se(PTR_TO_UID(UID_TO_PTR(1000)) == 1000);
21255d
 }
21255d
 
21255d
-static void test_valid_user_group_name_compat(void) {
21255d
+static void test_valid_user_group_name_relaxed(void) {
21255d
         log_info("/* %s */", __func__);
21255d
 
21255d
-        assert_se(!valid_user_group_name_compat(NULL));
21255d
-        assert_se(!valid_user_group_name_compat(""));
21255d
-        assert_se(!valid_user_group_name_compat("1"));
21255d
-        assert_se(!valid_user_group_name_compat("65535"));
21255d
-        assert_se(!valid_user_group_name_compat("-1"));
21255d
-        assert_se(!valid_user_group_name_compat("-kkk"));
21255d
-        assert_se(!valid_user_group_name_compat("rööt"));
21255d
-        assert_se(!valid_user_group_name_compat("."));
21255d
-        assert_se(!valid_user_group_name_compat(".eff"));
21255d
-        assert_se(!valid_user_group_name_compat("foo\nbar"));
21255d
-        assert_se(!valid_user_group_name_compat("0123456789012345678901234567890123456789"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("aaa:bbb"));
21255d
-        assert_se(!valid_user_group_name_compat("."));
21255d
-        assert_se(!valid_user_group_name_compat(".1"));
21255d
-        assert_se(!valid_user_group_name_compat(".65535"));
21255d
-        assert_se(!valid_user_group_name_compat(".-1"));
21255d
-        assert_se(!valid_user_group_name_compat(".-kkk"));
21255d
-        assert_se(!valid_user_group_name_compat(".rööt"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat(".aaa:bbb"));
21255d
-
21255d
-        assert_se(valid_user_group_name_compat("root"));
21255d
-        assert_se(valid_user_group_name_compat("lennart"));
21255d
-        assert_se(valid_user_group_name_compat("LENNART"));
21255d
-        assert_se(valid_user_group_name_compat("_kkk"));
21255d
-        assert_se(valid_user_group_name_compat("kkk-"));
21255d
-        assert_se(valid_user_group_name_compat("kk-k"));
21255d
-        assert_se(valid_user_group_name_compat("eff.eff"));
21255d
-        assert_se(valid_user_group_name_compat("eff."));
21255d
-
21255d
-        assert_se(valid_user_group_name_compat("some5"));
21255d
-        assert_se(valid_user_group_name_compat("5some"));
21255d
-        assert_se(valid_user_group_name_compat("INNER5NUMBER"));
21255d
+        assert_se(!valid_user_group_name(NULL, VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("1", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("65535", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("-1", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("foo\nbar", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("0123456789012345678901234567890123456789", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("aaa:bbb", VALID_USER_RELAX|VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name(".aaa:bbb", VALID_USER_RELAX|VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name(".", VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("..", VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("root", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("lennart", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("LENNART", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("_kkk", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("kkk-", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("kk-k", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("eff.eff", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("eff.", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("-kkk", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("rööt", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".eff", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".1", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".65535", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".-1", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".-kkk", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".rööt", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("...", VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("some5", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("5some", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("INNER5NUMBER", VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("piff.paff@ad.domain.example", VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("Dāvis", VALID_USER_RELAX));
21255d
 }
21255d
 
21255d
 static void test_valid_user_group_name(void) {
21255d
         log_info("/* %s */", __func__);
21255d
 
21255d
-        assert_se(!valid_user_group_name(NULL));
21255d
-        assert_se(!valid_user_group_name(""));
21255d
-        assert_se(!valid_user_group_name("1"));
21255d
-        assert_se(!valid_user_group_name("65535"));
21255d
-        assert_se(!valid_user_group_name("-1"));
21255d
-        assert_se(!valid_user_group_name("-kkk"));
21255d
-        assert_se(!valid_user_group_name("rööt"));
21255d
-        assert_se(!valid_user_group_name("."));
21255d
-        assert_se(!valid_user_group_name(".eff"));
21255d
-        assert_se(!valid_user_group_name("foo\nbar"));
21255d
-        assert_se(!valid_user_group_name("0123456789012345678901234567890123456789"));
21255d
-        assert_se(!valid_user_group_name_or_id("aaa:bbb"));
21255d
-        assert_se(!valid_user_group_name("."));
21255d
-        assert_se(!valid_user_group_name(".1"));
21255d
-        assert_se(!valid_user_group_name(".65535"));
21255d
-        assert_se(!valid_user_group_name(".-1"));
21255d
-        assert_se(!valid_user_group_name(".-kkk"));
21255d
-        assert_se(!valid_user_group_name(".rööt"));
21255d
-        assert_se(!valid_user_group_name_or_id(".aaa:bbb"));
21255d
-
21255d
-        assert_se(valid_user_group_name("root"));
21255d
-        assert_se(valid_user_group_name("lennart"));
21255d
-        assert_se(valid_user_group_name("LENNART"));
21255d
-        assert_se(valid_user_group_name("_kkk"));
21255d
-        assert_se(valid_user_group_name("kkk-"));
21255d
-        assert_se(valid_user_group_name("kk-k"));
21255d
-        assert_se(!valid_user_group_name("eff.eff"));
21255d
-        assert_se(!valid_user_group_name("eff."));
21255d
-
21255d
-        assert_se(valid_user_group_name("some5"));
21255d
-        assert_se(!valid_user_group_name("5some"));
21255d
-        assert_se(valid_user_group_name("INNER5NUMBER"));
21255d
+        assert_se(!valid_user_group_name(NULL, 0));
21255d
+        assert_se(!valid_user_group_name("", 0));
21255d
+        assert_se(!valid_user_group_name("1", 0));
21255d
+        assert_se(!valid_user_group_name("65535", 0));
21255d
+        assert_se(!valid_user_group_name("-1", 0));
21255d
+        assert_se(!valid_user_group_name("-kkk", 0));
21255d
+        assert_se(!valid_user_group_name("rööt", 0));
21255d
+        assert_se(!valid_user_group_name(".", 0));
21255d
+        assert_se(!valid_user_group_name(".eff", 0));
21255d
+        assert_se(!valid_user_group_name("foo\nbar", 0));
21255d
+        assert_se(!valid_user_group_name("0123456789012345678901234567890123456789", 0));
21255d
+        assert_se(!valid_user_group_name("aaa:bbb", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name(".", 0));
21255d
+        assert_se(!valid_user_group_name("..", 0));
21255d
+        assert_se(!valid_user_group_name("...", 0));
21255d
+        assert_se(!valid_user_group_name(".1", 0));
21255d
+        assert_se(!valid_user_group_name(".65535", 0));
21255d
+        assert_se(!valid_user_group_name(".-1", 0));
21255d
+        assert_se(!valid_user_group_name(".-kkk", 0));
21255d
+        assert_se(!valid_user_group_name(".rööt", 0));
21255d
+        assert_se(!valid_user_group_name(".aaa:bbb", VALID_USER_ALLOW_NUMERIC));
21255d
+
21255d
+        assert_se(valid_user_group_name("root", 0));
21255d
+        assert_se(valid_user_group_name("lennart", 0));
21255d
+        assert_se(valid_user_group_name("LENNART", 0));
21255d
+        assert_se(valid_user_group_name("_kkk", 0));
21255d
+        assert_se(valid_user_group_name("kkk-", 0));
21255d
+        assert_se(valid_user_group_name("kk-k", 0));
21255d
+        assert_se(!valid_user_group_name("eff.eff", 0));
21255d
+        assert_se(!valid_user_group_name("eff.", 0));
21255d
+
21255d
+        assert_se(valid_user_group_name("some5", 0));
21255d
+        assert_se(!valid_user_group_name("5some", 0));
21255d
+        assert_se(valid_user_group_name("INNER5NUMBER", 0));
21255d
+
21255d
+        assert_se(!valid_user_group_name("piff.paff@ad.domain.example", 0));
21255d
+        assert_se(!valid_user_group_name("Dāvis", 0));
21255d
 }
21255d
 
21255d
-static void test_valid_user_group_name_or_id_compat(void) {
21255d
+static void test_valid_user_group_name_or_numeric_relaxed(void) {
21255d
         log_info("/* %s */", __func__);
21255d
 
21255d
-        assert_se(!valid_user_group_name_or_id_compat(NULL));
21255d
-        assert_se(!valid_user_group_name_or_id_compat(""));
21255d
-        assert_se(valid_user_group_name_or_id_compat("0"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("1"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("65534"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("65535"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("65536"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("-1"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("-kkk"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("rööt"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("."));
21255d
-        assert_se(!valid_user_group_name_or_id_compat(".eff"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("eff.eff"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("eff."));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("foo\nbar"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("0123456789012345678901234567890123456789"));
21255d
-        assert_se(!valid_user_group_name_or_id_compat("aaa:bbb"));
21255d
-
21255d
-        assert_se(valid_user_group_name_or_id_compat("root"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("lennart"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("LENNART"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("_kkk"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("kkk-"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("kk-k"));
21255d
-
21255d
-        assert_se(valid_user_group_name_or_id_compat("some5"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("5some"));
21255d
-        assert_se(valid_user_group_name_or_id_compat("INNER5NUMBER"));
21255d
+        assert_se(!valid_user_group_name(NULL, VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("0", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("1", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("65534", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("65535", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("65536", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("-1", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("foo\nbar", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("0123456789012345678901234567890123456789", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("aaa:bbb", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name(".", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(!valid_user_group_name("..", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("root", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("lennart", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("LENNART", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("_kkk", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("kkk-", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("kk-k", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("-kkk", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("rööt", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name(".eff", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("eff.eff", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("eff.", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("...", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("some5", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("5some", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("INNER5NUMBER", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+
21255d
+        assert_se(valid_user_group_name("piff.paff@ad.domain.example", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
+        assert_se(valid_user_group_name("Dāvis", VALID_USER_ALLOW_NUMERIC|VALID_USER_RELAX));
21255d
 }
21255d
 
21255d
-static void test_valid_user_group_name_or_id(void) {
21255d
+static void test_valid_user_group_name_or_numeric(void) {
21255d
         log_info("/* %s */", __func__);
21255d
 
21255d
-        assert_se(!valid_user_group_name_or_id(NULL));
21255d
-        assert_se(!valid_user_group_name_or_id(""));
21255d
-        assert_se(valid_user_group_name_or_id("0"));
21255d
-        assert_se(valid_user_group_name_or_id("1"));
21255d
-        assert_se(valid_user_group_name_or_id("65534"));
21255d
-        assert_se(!valid_user_group_name_or_id("65535"));
21255d
-        assert_se(valid_user_group_name_or_id("65536"));
21255d
-        assert_se(!valid_user_group_name_or_id("-1"));
21255d
-        assert_se(!valid_user_group_name_or_id("-kkk"));
21255d
-        assert_se(!valid_user_group_name_or_id("rööt"));
21255d
-        assert_se(!valid_user_group_name_or_id("."));
21255d
-        assert_se(!valid_user_group_name_or_id(".eff"));
21255d
-        assert_se(!valid_user_group_name_or_id("eff.eff"));
21255d
-        assert_se(!valid_user_group_name_or_id("eff."));
21255d
-        assert_se(!valid_user_group_name_or_id("foo\nbar"));
21255d
-        assert_se(!valid_user_group_name_or_id("0123456789012345678901234567890123456789"));
21255d
-        assert_se(!valid_user_group_name_or_id("aaa:bbb"));
21255d
-
21255d
-        assert_se(valid_user_group_name_or_id("root"));
21255d
-        assert_se(valid_user_group_name_or_id("lennart"));
21255d
-        assert_se(valid_user_group_name_or_id("LENNART"));
21255d
-        assert_se(valid_user_group_name_or_id("_kkk"));
21255d
-        assert_se(valid_user_group_name_or_id("kkk-"));
21255d
-        assert_se(valid_user_group_name_or_id("kk-k"));
21255d
-
21255d
-        assert_se(valid_user_group_name_or_id("some5"));
21255d
-        assert_se(!valid_user_group_name_or_id("5some"));
21255d
-        assert_se(valid_user_group_name_or_id("INNER5NUMBER"));
21255d
+        assert_se(!valid_user_group_name(NULL, VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("0", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("1", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("65534", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("65535", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("65536", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("-1", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("-kkk", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("rööt", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name(".", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("..", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("...", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name(".eff", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("eff.eff", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("eff.", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("foo\nbar", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("0123456789012345678901234567890123456789", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("aaa:bbb", VALID_USER_ALLOW_NUMERIC));
21255d
+
21255d
+        assert_se(valid_user_group_name("root", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("lennart", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("LENNART", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("_kkk", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("kkk-", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("kk-k", VALID_USER_ALLOW_NUMERIC));
21255d
+
21255d
+        assert_se(valid_user_group_name("some5", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("5some", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(valid_user_group_name("INNER5NUMBER", VALID_USER_ALLOW_NUMERIC));
21255d
+
21255d
+        assert_se(!valid_user_group_name("piff.paff@ad.domain.example", VALID_USER_ALLOW_NUMERIC));
21255d
+        assert_se(!valid_user_group_name("Dāvis", VALID_USER_ALLOW_NUMERIC));
21255d
 }
21255d
 
21255d
 static void test_valid_gecos(void) {
21255d
@@ -367,10 +386,10 @@ int main(int argc, char*argv[]) {
21255d
         test_parse_uid();
21255d
         test_uid_ptr();
21255d
 
21255d
-        test_valid_user_group_name_compat();
21255d
+        test_valid_user_group_name_relaxed();
21255d
         test_valid_user_group_name();
21255d
-        test_valid_user_group_name_or_id_compat();
21255d
-        test_valid_user_group_name_or_id();
21255d
+        test_valid_user_group_name_or_numeric_relaxed();
21255d
+        test_valid_user_group_name_or_numeric();
21255d
         test_valid_gecos();
21255d
         test_valid_home();
21255d