crypt(3C) Standard C Library Functions crypt(3C)NAMEcrypt - string encoding function
SYNOPSIS
#include <crypt.h>
char *crypt(const char *key, const char *salt);
Standard conforming
#include <unistd.h>
char *crypt(const char *key, const char *salt);
DESCRIPTION
The crypt() function encodes strings suitable for secure storage as
passwords. It generates the password hash given the key and salt.
The key argument is the plain text password to be encrypted.
If the first character of salt is "$", crypt() uses crypt.conf(4) to
determine which shared module to load for the encryption algorithm.
The algorithm name crypt() uses to search in crypt.conf is the string
between the first and second "$", or between the first "$" and first
"," if a "," comes before the second "$".
If the first character of salt is not "$", the algorithm described on
crypt_unix(5) is used.
RETURN VALUES
Upon successful completion, crypt() returns a pointer to the encoded
string. Otherwise it returns a null pointer and sets errno to indicate
the error.
The return value points to static data that is overwritten by each
call.
ERRORS
The crypt() function will fail if:
EINVAL An entry in crypt.conf is invalid.
ELIBACC The required shared library was not found.
ENOMEM There is insufficient memory to generate the hash.
ENOSYS The functionality is not supported on this system.
USAGE
The values returned by this function might not be portable among stan‐
dard-conforming systems. See standards(5).
Applications should not use crypt() to store or verify user passwords
but should use the functions described on pam(3PAM) instead.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Standard │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOpasswd(1), crypt_genhash_impl(3C), crypt_gensalt(3C), crypt_gen‐
salt_impl(3C), getpassphrase(3C), pam(3PAM), passwd(4), policy.conf(4),
attributes(5), crypt_unix(5), standards(5)SunOS 5.10 28 Sep 2004 crypt(3C)