CRYPT_UNIX(7) Standards, Environments, and Macros CRYPT_UNIX(7)
NAME
crypt_unix - traditional UNIX crypt algorithm
DESCRIPTION
The
crypt_unix algorithm is the traditional UNIX crypt algorithm. It is
not considered sufficiently secure for current systems and is provided
for backwards compatibility. The
crypt_sunmd5(7),
crypt_bsdmd5(7), or
crypt_bsdbf(7) algorithm should be used instead.
The algorithm identifier for
policy.conf(5) is
__unix__. There is no
entry in
crypt.conf(5) for this algorithm.
The
crypt_unix algorithm is internal to
libc and provides the string
encoding function used by
crypt(3C) when the first character of the salt
is not a "$".
This algorithm is based on a one-way encryption algorithm with variations
intended (among other things) to frustrate use of hardware
implementations of a key search. Only the first eight characters of the
key passed to
crypt() are used with this algorithm; the rest are silently
ignored. The salt is a two-character string chosen from the set [a-zA-
Z0-9./]. This string is used to perturb the hashing algorithm in one of
4096 different ways.
The maximum password length for
crypt_unix is 8 characters.
USAGE
The return value of the
crypt_unix algorithm might not be portable among
standard-conforming systems. See
standards(7).
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT-Level | Safe |
+---------------+-----------------+
SEE ALSO
passwd(1),
crypt(3C),
crypt_genhash_impl(3C),
crypt_gensalt(3C),
crypt_gensalt_impl(3C),
getpassphrase(3C),
crypt.conf(5),
passwd(5),
policy.conf(5),
attributes(7),
crypt_bsdbf(7),
crypt_bsdmd5(7),
crypt_sunmd5(7),
standards(7) August 6, 2003
CRYPT_UNIX(7)