busybox/libbb/die_if_bad_username.c
Denys Vlasenko cb7edc2661 adduser: copy /etc/skel to mew homes. +100 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-02-06 21:50:59 +01:00

41 lines
1011 B
C

/* vi: set sw=4 ts=4: */
/*
* Check user and group names for illegal characters
*
* Copyright (C) 2008 Tito Ragusa <farmatito@tiscali.it>
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
/* To avoid problems, the username should consist only of
* letters, digits, underscores, periods, at signs and dashes,
* and not start with a dash (as defined by IEEE Std 1003.1-2001).
* For compatibility with Samba machine accounts $ is also supported
* at the end of the username.
*/
void FAST_FUNC die_if_bad_username(const char *name)
{
/* 1st char being dash or dot isn't valid: */
goto skip;
/* For example, name like ".." can make adduser
* chown "/home/.." recursively - NOT GOOD
*/
do {
if (*name == '-' || *name == '.')
continue;
skip:
if (isalnum(*name)
|| *name == '_'
|| *name == '@'
|| (*name == '$' && !name[1])
) {
continue;
}
bb_error_msg_and_die("illegal character '%c'", *name);
} while (*++name);
}