/usr/bin/[ 这个是否后门程序?

crazysoul

系统是centos 4
发现有个可执行的文件:
ls -lah "/usr/bin/["
-rwxr-xr-x   1 root     root          27k Aug 23  2005 [


strings "/usr/bin/["

/lib/ld-linux.so.2
PTRh
QVhY
[^_]
,0<     wp
<->ul
<-.t
[^_]
[^_]
[^_]
[^_]
[^_]
[^_]
[^_]
t5~$
[^_]
[^_]
8!uY
[^_]
[^_]
[^_]
[^_]
[^_]
[^_]
[^_]
|[^_]
|[^_]
[^_]
[^_]
0^_]
@[^]
[^_]
[^_]
[^_]
%s:
argument expected
unknown binary operator
before -eq
after -gt
before -gt
after -eq
after -lt
before -lt
before -ge
after -ge
before -le
after -ne
before -ne
after -le
-nt does not accept -l
-ef does not accept -l
-ot does not accept -l
after -t
%s: unary operator expected
%s: binary operator expected
')' expected, found %s
')' expected
Report bugs to <%s>.
bug-coreutils@gnu.org
/usr/share/locale
Matthew Bradburn
Kevin Braunsdorf
5.2.1
GNU coreutils
missing `]'
too many arguments
%s: integer expression expected
Try `%s --help' for more information.
Usage: test EXPRESSION
  or:  [ EXPRESSION ]
  or:  [ OPTION
Exit with the status determined by EXPRESSION.
      --help     display this help and exit
      --version  output version information and exit
EXPRESSION is true or false and sets exit status.  It is one of:
  ( EXPRESSION )               EXPRESSION is true
  ! EXPRESSION                 EXPRESSION is false
  EXPRESSION1 -a EXPRESSION2   both EXPRESSION1 and EXPRESSION2 are true
  EXPRESSION1 -o EXPRESSION2   either EXPRESSION1 or EXPRESSION2 is true
  [-n] STRING          the length of STRING is nonzero
  -z STRING            the length of STRING is zero
  STRING1 = STRING2    the strings are equal
  STRING1 != STRING2   the strings are not equal
  INTEGER1 -eq INTEGER2   INTEGER1 is equal to INTEGER2
  INTEGER1 -ge INTEGER2   INTEGER1 is greater than or equal to INTEGER2
  INTEGER1 -gt INTEGER2   INTEGER1 is greater than INTEGER2
  INTEGER1 -le INTEGER2   INTEGER1 is less than or equal to INTEGER2
  INTEGER1 -lt INTEGER2   INTEGER1 is less than INTEGER2
  INTEGER1 -ne INTEGER2   INTEGER1 is not equal to INTEGER2
  FILE1 -ef FILE2   FILE1 and FILE2 have the same device and inode numbers
  FILE1 -nt FILE2   FILE1 is newer (modification date) than FILE2
  FILE1 -ot FILE2   FILE1 is older than FILE2
  -b FILE     FILE exists and is block special
  -c FILE     FILE exists and is character special
  -d FILE     FILE exists and is a directory
  -e FILE     FILE exists
  -f FILE     FILE exists and is a regular file
  -g FILE     FILE exists and is set-group-ID
  -h FILE     FILE exists and is a symbolic link (same as -L)
  -G FILE     FILE exists and is owned by the effective group ID
  -k FILE     FILE exists and has its sticky bit set
  -L FILE     FILE exists and is a symbolic link (same as -h)
  -O FILE     FILE exists and is owned by the effective user ID
  -p FILE     FILE exists and is a named pipe
  -r FILE     FILE exists and is readable
  -s FILE     FILE exists and has a size greater than zero
  -S FILE     FILE exists and is a socket
  -t [FD]     file descriptor FD (stdout by default) is opened on a terminal
  -u FILE     FILE exists and its set-user-ID bit is set
  -w FILE     FILE exists and is writable
  -x FILE     FILE exists and is executable
Beware that parentheses need to be escaped (e.g., by backslashes) for shells.
INTEGER may also be -l STRING, which evaluates to the length of STRING.
write error
%s: %s
help
version
literal
shell
shell-always
escape
clocale
Copyright (C) 2004 Free Software Foundation, Inc.
Written by %s, %s, %s,
%s, %s, %s, %s,
%s, %s, and others.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Written by %s, %s, %s,
%s, %s, %s, %s,
%s, and %s.
Written by %s, %s, %s,
%s, %s, %s, %s,
and %s.
Written by %s, %s, %s,
%s, %s, %s, and %s.
Written by %s, %s, %s,
%s, %s, and %s.
Written by %s, %s, %s,
%s, and %s.
Written by %s, %s, %s,
and %s.
%s (%s) %s
Written by %s, %s, and %s.
Written by %s and %s.
Written by %s.
%s %s
memory exhausted
_Jv_RegisterClasses
__gmon_start__
libc.so.6
getgid
geteuid
getopt_long
__fpending
getegid
memcpy
__overflow
mbrtowc
getuid
malloc
isatty
opterr
abort
iswprint
calloc
__ctype_get_mb_cur_max
fputs_unlocked
dcgettext
setregid
optind
realloc
__xstat64
setreuid
memset
strcmp
fclose
setlocale
stderr
error
__lxstat64
__ctype_b_loc
fflush_unlocked
access
__errno_location
bindtextdomain
_IO_stdin_used
__libc_start_main
vfprintf
free
mbsinit
__cxa_atexit
xalloc_fail_func
usage
close_stdout
version_etc_copyright
program_name
exit_failure
xalloc_msg_memory_exhausted
GLIBC_2.3
GLIBC_2.1.3
GLIBC_2.1
GLIBC_2.0
GLIBC_2.2
/lib/ld-linux.so.2


有相同系统的可否帮忙看看

晨想

不是木马，是正规程序。

crazysoul

有什么用的?
我把它改了名再执行 [ 也还是一样

晨想

[ 和 test 是同一个程序。。。[ 是程序，也是shell builtin

Yuri

好象再Shell里面常用哦.