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Goal: Relaxed usernames/groupnames checking patch.
Status wrt upstream: Debian specific. Not to be used upstream
Details:
Allows any non-empty user/grounames that don't contain ':', ',' or '\n'
characters and don't start with '-', '+', or '~'. This patch is more
restrictive than original Karl's version. closes: #264879
Also closes: #377844
Comments from Karl Ramm (shadow 1:4.0.3-9, 20 Aug 2003 02:06:50 -0400):
I can't come up with a good justification as to why characters other
than ':'s and '\0's should be disallowed in group and usernames (other
than '-' as the leading character). Thus, the maintenance tools don't
anymore. closes: #79682, #166798, #171179
--- a/libmisc/chkname.c
+++ b/libmisc/chkname.c
@@ -54,6 +54,7 @@
return true;
}
+#if 0
/*
* User/group names must match [a-z_][a-z0-9_-]*[$]
*/
@@ -73,6 +74,26 @@
return false;
}
}
+#endif
+ /*
+ * POSIX indicate that usernames are composed of characters from the
+ * portable filename character set [A-Za-z0-9._-], and that the hyphen
+ * should not be used as the first character of a portable user name.
+ *
+ * Allow more relaxed user/group names in Debian -- ^[^-~+:,\s][^:,\s]*$
+ */
+ if ( ('\0' == *name)
+ || ('-' == *name)
+ || ('~' == *name)
+ || ('+' == *name)) {
+ return false;
+ }
+ do {
+ if ((':' == *name) || (',' == *name) || isspace(*name)) {
+ return false;
+ }
+ name++;
+ } while ('\0' != *name);
return true;
}
--- a/man/useradd.8.xml
+++ b/man/useradd.8.xml
@@ -662,12 +662,20 @@
</para>
<para>
- Usernames must start with a lower case letter or an underscore,
+ It is usually recommended to only use usernames that begin with a lower case letter or an underscore,
followed by lower case letters, digits, underscores, or dashes.
They can end with a dollar sign.
In regular expression terms: [a-z_][a-z0-9_-]*[$]?
</para>
<para>
+ On Debian, the only constraints are that usernames must neither start
+ with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a
+ colon (':'), a comma (','), or a whitespace (space: ' ',
+ end of line: '\n', tabulation: '\t', etc.). Note that using a slash
+ ('/') may break the default algorithm for the definition of the
+ user's home directory.
+ </para>
+ <para>
Usernames may only be up to 32 characters long.
</para>
</refsect1>
--- a/man/groupadd.8.xml
+++ b/man/groupadd.8.xml
@@ -273,12 +273,18 @@
<refsect1 id='caveats'>
<title>CAVEATS</title>
<para>
- Groupnames must start with a lower case letter or an underscore,
+ It is usually recommended to only use groupnames that begin with a lower case letter or an underscore,
followed by lower case letters, digits, underscores, or dashes.
They can end with a dollar sign.
In regular expression terms: [a-z_][a-z0-9_-]*[$]?
</para>
<para>
+ On Debian, the only constraints are that groupnames must neither start
+ with a dash ('-') nor plus ('+') nor tilde ('~') nor contain a
+ colon (':'), a comma (','), or a whitespace (space:' ',
+ end of line: '\n', tabulation: '\t', etc.).
+ </para>
+ <para>
Groupnames may only be up to &GROUP_NAME_MAX_LENGTH; characters long.
</para>
<para>
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