/* passwd-pwent.c --- verifying typed passwords with the OS.
* xscreensaver, Copyright (c) 1993-1998 Jamie Zawinski <jwz@jwz.org>
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation. No representations are made about the suitability of this
* software for any purpose. It is provided "as is" without express or
* implied warranty.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifndef NO_LOCKING /* whole file */
#include <stdlib.h>
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_CRYPT_H
# include <crypt.h>
#endif
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#ifndef VMS
# include <pwd.h>
# include <grp.h>
#else /* VMS */
# include "vms-pwd.h"
#endif /* VMS */
#ifdef __bsdi__
# include <sys/param.h>
# if _BSDI_VERSION >= 199608
# define BSD_AUTH
# endif
#endif /* __bsdi__ */
#if defined(HAVE_SHADOW_PASSWD) /* passwds live in /etc/shadow */
# include <shadow.h>
# define PWTYPE struct spwd *
# define PWPSLOT sp_pwdp
# define GETPW getspnam
#elif defined(HAVE_ENHANCED_PASSWD) /* passwds live in /tcb/files/auth/ */
/* M.Matsumoto <matsu@yao.sharp.co.jp> */
# include <sys/security.h>
# include <prot.h>
# define PWTYPE struct pr_passwd *
# define PWPSLOT ufld.fd_encrypt
# define GETPW getprpwnam
#elif defined(HAVE_ADJUNCT_PASSWD)
# include <sys/label.h>
# include <sys/audit.h>
# include <pwdadj.h>
# define PWTYPE struct passwd_adjunct *
# define PWPSLOT pwa_passwd
# define GETPW getpwanam
#elif defined(HAVE_HPUX_PASSWD)
# include <hpsecurity.h>
# include <prot.h>
# define PWTYPE struct s_passwd *
# define PWPSLOT pw_passwd
# define GETPW getspwnam
# define HAVE_BIGCRYPT
#endif
/* blargh */
#undef Bool
#undef True
#undef False
#define Bool int
#define True 1
#define False 0
extern const char *blurb(void);
static char *encrypted_root_passwd = 0;
static char *encrypted_user_passwd = 0;
#ifdef VMS
# define ROOT "SYSTEM"
#else
# define ROOT "root"
#endif
#ifndef VMS
Bool pwent_priv_init (int argc, char **argv, Bool verbose_p);
Bool pwent_lock_init (int argc, char **argv, Bool verbose_p);
Bool pwent_passwd_valid_p (const char *typed_passwd, Bool verbose_p);
#endif
#ifndef VMS
static char *
user_name (void)
{
/* I think that just checking $USER here is not the best idea. */
const char *u = 0;
/* It has been reported that getlogin() returns the wrong user id on some
very old SGI systems... And I've seen it return the string "rlogin"
sometimes! Screw it, using getpwuid() should be enough...
*/
/* u = (char *) getlogin ();
*/
/* getlogin() fails if not attached to a terminal; in that case, use
getpwuid(). (Note that in this case, we're not doing shadow stuff, since
all we're interested in is the name, not the password. So that should
still work. Right?) */
if (!u || !*u)
{
struct passwd *p = getpwuid (getuid ());
u = (p ? p->pw_name : 0);
}
return (u ? strdup(u) : 0);
}
#else /* VMS */
static char *
user_name (void)
{
char *u = getenv("USER");
return (u ? strdup(u) : 0);
}
#endif /* VMS */
static Bool
passwd_known_p (const char *pw)
{
return (pw &&
pw[0] != '*' && /* This would be sensible... */
strlen(pw) > 4); /* ...but this is what Solaris does. */
}
static char *
get_encrypted_passwd(const char *user)
{
char *result = 0;
#ifdef PWTYPE
if (user && *user && !result)
{ /* First check the shadow passwords. */
PWTYPE p = GETPW((char *) user);
if (p && passwd_known_p (p->PWPSLOT))
result = strdup(p->PWPSLOT);
}
#endif /* PWTYPE */
if (user && *user && !result)
{ /* Check non-shadow passwords too. */
struct passwd *p = getpwnam(user);
if (p && passwd_known_p (p->pw_passwd))
result = strdup(p->pw_passwd);
}
/* The manual for passwd(4) on HPUX 10.10 says:
Password aging is put in effect for a particular user if his
encrypted password in the password file is followed by a comma and
a nonnull string of characters from the above alphabet. This
string defines the "age" needed to implement password aging.
So this means that passwd->pw_passwd isn't simply a string of cyphertext,
it might have trailing junk. So, if there is a comma in the string, and
that comma is beyond position 13, terminate the string before the comma.
*/
if (result && strlen(result) > 13)
{
char *s = strchr (result+13, ',');
if (s)
*s = 0;
}
#ifndef HAVE_PAM
/* We only issue this warning if not compiled with support for PAM.
If we're using PAM, it's not unheard of that normal pwent passwords
would be unavailable. */
if (!result)
fprintf (stderr, "%s: couldn't get password of \"%s\"\n",
blurb(), (user ? user : "(null)"));
#endif /* !HAVE_PAM */
return result;
}
/* This has to be called before we've changed our effective user ID,
because it might need privileges to get at the encrypted passwords.
Returns false if we weren't able to get any passwords, and therefore,
locking isn't possible. (It will also have written to stderr.)
*/
#ifndef VMS
Bool
pwent_priv_init (int argc, char **argv, Bool verbose_p)
{
char *u;
#ifdef HAVE_ENHANCED_PASSWD
set_auth_parameters(argc, argv);
check_auth_parameters();
#endif /* HAVE_DEC_ENHANCED */
u = user_name();
encrypted_user_passwd = get_encrypted_passwd(u);
encrypted_root_passwd = get_encrypted_passwd(ROOT);
if (u) free (u);
if (encrypted_user_passwd)
return True;
else
return False;
}
Bool
pwent_lock_init (int argc, char **argv, Bool verbose_p)
{
if (encrypted_user_passwd)
return True;
else
return False;
}
static Bool
passwds_match_p (const char *cleartext, const char *ciphertext)
{
char *s = 0; /* note that on some systems, crypt() may return null */
s = (char *) crypt (cleartext, ciphertext);
if (s && !strcmp (s, ciphertext))
return True;
#ifdef HAVE_BIGCRYPT
/* There seems to be no way to tell at runtime if an HP machine is in
"trusted" mode, and thereby, which of crypt() or bigcrypt() we should
be calling to compare passwords. So call them both, and see which
one works. */
s = (char *) bigcrypt (cleartext, ciphertext);
if (s && !strcmp (s, ciphertext))
return True;
#endif /* HAVE_BIGCRYPT */
return False;
}
/* This can be called at any time, and says whether the typed password
belongs to either the logged in user (real uid, not effective); or
to root.
*/
Bool
pwent_passwd_valid_p (const char *typed_passwd, Bool verbose_p)
{
if (encrypted_user_passwd &&
passwds_match_p (typed_passwd, encrypted_user_passwd))
return True;
#ifdef ALLOW_ROOT_PASSWD
/* do not allow root to have a null password. */
else if (typed_passwd[0] &&
encrypted_root_passwd &&
passwds_match_p (typed_passwd, encrypted_root_passwd))
return True;
#endif /* ALLOW_ROOT_PASSWD */
else
return False;
}
#else /* VMS */
Bool pwent_lock_init (int argc, char **argv, Bool verbose_p) { return True; }
#endif /* VMS */
#endif /* NO_LOCKING -- whole file */
