[svn-upgrade] Integrating new upstream version, shadow (19990709)
This commit is contained in:
nekral-guest
548
lib/pwauth.c
Normal file
548
lib/pwauth.c
Normal file
@@ -0,0 +1,548 @@
|
||||
/*
|
||||
* Copyright 1992 - 1994, Julianne Frances Haugh
|
||||
* All rights reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
|
||||
* may be used to endorse or promote products derived from this software
|
||||
* without specific prior written permission.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
|
||||
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
|
||||
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*/
|
||||
|
||||
#include <config.h>
|
||||
|
||||
#include "rcsid.h"
|
||||
RCSID("$Id: pwauth.c,v 1.9 1998/12/28 20:34:38 marekm Exp $")
|
||||
|
||||
#include <sys/types.h>
|
||||
#include <signal.h>
|
||||
#include <fcntl.h>
|
||||
#include <stdio.h>
|
||||
#include <errno.h>
|
||||
#include "prototypes.h"
|
||||
#include "defines.h"
|
||||
#include "pwauth.h"
|
||||
#include "getdef.h"
|
||||
|
||||
#ifdef SKEY
|
||||
#include <skey.h>
|
||||
#endif
|
||||
|
||||
#ifdef OPIE
|
||||
#include <opie.h>
|
||||
#endif
|
||||
|
||||
#ifdef __linux__ /* standard password prompt by default */
|
||||
static const char *PROMPT = gettext_noop("Password: ");
|
||||
#else
|
||||
static const char *PROMPT = gettext_noop("%s's Password:");
|
||||
#endif
|
||||
|
||||
extern char *getpass();
|
||||
|
||||
#ifdef AUTH_METHODS
|
||||
/*
|
||||
* Look-up table for bound-in methods. Put the name that the
|
||||
* method is known by in the password field as "name" and a
|
||||
* pointer to the function
|
||||
*/
|
||||
|
||||
struct method {
|
||||
char *name;
|
||||
int (*func) P_((const char *, int, const char *));
|
||||
};
|
||||
|
||||
#ifdef PAD_AUTH
|
||||
int pad_auth();
|
||||
#endif
|
||||
static struct method methods[] = {
|
||||
#ifdef PAD_AUTH
|
||||
{ "pad", pad_auth },
|
||||
#endif
|
||||
{ "", 0 }
|
||||
};
|
||||
#endif /* AUTH_METHODS */
|
||||
|
||||
int wipe_clear_pass = 1;
|
||||
char *clear_pass = NULL;
|
||||
|
||||
/*
|
||||
* _old_auth - perform getpass/crypt authentication
|
||||
*
|
||||
* _old_auth gets the user's cleartext password and encrypts it
|
||||
* using the salt in the encrypted password. The results are
|
||||
* compared.
|
||||
*/
|
||||
|
||||
static int
|
||||
_old_auth(const char *cipher, const char *user, int reason, const char *input)
|
||||
{
|
||||
char prompt[1024];
|
||||
char *clear = NULL;
|
||||
const char *cp;
|
||||
int retval;
|
||||
#ifdef SKEY
|
||||
int use_skey = 0;
|
||||
char challenge_info[40];
|
||||
struct skey skey;
|
||||
#endif
|
||||
|
||||
#ifdef OPIE
|
||||
int use_opie = 0;
|
||||
char o_challenge_info[OPIE_CHALLENGE_MAX + 1];
|
||||
struct opie opie;
|
||||
/*
|
||||
* This implementation is based almost entirely on the SKEY code
|
||||
* above. Thus the opie struct is called skey, etc. I am unaware
|
||||
* if the system works at the same time, but I cannot imagine why
|
||||
* anyone would want to do this....
|
||||
* -- A.R.
|
||||
* Mod: 5/14/98 A.R.
|
||||
* Made the OPIE code separate from the S/Key code. Now
|
||||
* (conceivably) both can be compiled in and function apart from
|
||||
* one another (assuming a sysadmin really wants to maintain OPIE
|
||||
* and an S/Key databases....).
|
||||
*
|
||||
* Also cleaned up the code a bit. Will be adding second-prompt
|
||||
* support (the traditional Echo-on S/Key/OPIE-only prompts to let
|
||||
* the users see the one-time passwords they are typing/pasting
|
||||
* in....
|
||||
* -- A.R.
|
||||
*/
|
||||
#endif
|
||||
|
||||
/*
|
||||
* There are programs for adding and deleting authentication data.
|
||||
*/
|
||||
|
||||
if (reason == PW_ADD || reason == PW_DELETE)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* There are even programs for changing the user name ...
|
||||
*/
|
||||
|
||||
if (reason == PW_CHANGE && input != (char *) 0)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* WARNING:
|
||||
*
|
||||
* When we change a password and we are root, we don't prompt.
|
||||
* This is so root can change any password without having to
|
||||
* know it. This is a policy decision that might have to be
|
||||
* revisited.
|
||||
*/
|
||||
|
||||
if (reason == PW_CHANGE && getuid () == 0)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* WARNING:
|
||||
*
|
||||
* When we are logging in a user with no ciphertext password,
|
||||
* we don't prompt for the password or anything. In reality
|
||||
* the user could just hit <ENTER>, so it doesn't really
|
||||
* matter.
|
||||
*/
|
||||
|
||||
if (cipher == (char *) 0 || *cipher == '\0')
|
||||
return 0;
|
||||
|
||||
#ifdef SKEY
|
||||
/*
|
||||
* If the user has an S/KEY entry show them the pertinent info
|
||||
* and then we can try validating the created cyphertext and the SKEY.
|
||||
* If there is no SKEY information we default to not using SKEY.
|
||||
*/
|
||||
|
||||
if (skeychallenge (&skey, user, challenge_info) == 0)
|
||||
use_skey = 1;
|
||||
#endif
|
||||
|
||||
#ifdef OPIE
|
||||
/*
|
||||
* Ditto above, for OPIE passwords.
|
||||
* -- AR
|
||||
*/
|
||||
|
||||
o_challenge_info[0] = '\0';
|
||||
if (opiechallenge(&opie, user, o_challenge_info) == 0)
|
||||
use_opie = 1;
|
||||
|
||||
if (use_opie == 0)
|
||||
opieverify(&opie, (char *)NULL);
|
||||
/*
|
||||
* This call to opieverify is necessary within OPIE's interface:
|
||||
* Every call to opiechallenge(), which checks to see if the user
|
||||
* has an OPIE password, and if so get the challenge, must be
|
||||
* accompanied by exactly one call to opieverify, which clears
|
||||
* any outstanding locks, and otherwise cleans up.
|
||||
* -- AR
|
||||
*/
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Prompt for the password as required. FTPD and REXECD both
|
||||
* get the cleartext password for us.
|
||||
*/
|
||||
|
||||
if (reason != PW_FTP && reason != PW_REXEC && !input) {
|
||||
if (! (cp = getdef_str ("LOGIN_STRING")))
|
||||
cp = PROMPT;
|
||||
#ifdef SKEY
|
||||
if (use_skey)
|
||||
printf ("[%s]\n", challenge_info);
|
||||
#endif
|
||||
|
||||
#ifdef OPIE
|
||||
if (use_opie)
|
||||
printf("[ %s ]\n", o_challenge_info);
|
||||
#endif
|
||||
|
||||
snprintf(prompt, sizeof prompt, cp, user);
|
||||
clear = getpass(_(prompt));
|
||||
if (!clear) {
|
||||
static char c[1];
|
||||
c[0] = '\0';
|
||||
clear = c;
|
||||
}
|
||||
input = clear;
|
||||
}
|
||||
|
||||
/*
|
||||
* Convert the cleartext password into a ciphertext string.
|
||||
* If the two match, the return value will be zero, which is
|
||||
* SUCCESS. Otherwise we see if SKEY is being used and check
|
||||
* the results there as well.
|
||||
*/
|
||||
|
||||
retval = strcmp(pw_encrypt(input, cipher), cipher);
|
||||
|
||||
#ifdef OPIE
|
||||
/*
|
||||
* This is required because using OPIE, opieverify() MUST be called
|
||||
* opiechallenge() above even if OPIE isn't being used in this case,
|
||||
* so locks get released, etc.
|
||||
* -- AR
|
||||
*/
|
||||
|
||||
if ((retval == 0) && use_opie)
|
||||
opieverify(&opie, (char *)NULL);
|
||||
#endif
|
||||
|
||||
#ifdef SKEY
|
||||
if (retval && use_skey) {
|
||||
int passcheck = -1;
|
||||
|
||||
#if 0 /* some skey libs don't have skey_passcheck. --marekm */
|
||||
passcheck = skey_passcheck(user, input);
|
||||
#else
|
||||
if (skeyverify(&skey, input) == 0)
|
||||
passcheck = skey.n;
|
||||
#endif /* if 0 */
|
||||
if (passcheck > 0)
|
||||
retval = 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
#ifdef OPIE
|
||||
if (retval && use_opie) {
|
||||
if (opieverify(&opie, input) == 0)
|
||||
retval = 0;
|
||||
}
|
||||
#endif /* OPIE */
|
||||
|
||||
/*
|
||||
* Things like RADIUS authentication may need the password -
|
||||
* if the external variable wipe_clear_pass is zero, we will
|
||||
* not wipe it (the caller should wipe clear_pass when it is
|
||||
* no longer needed). --marekm
|
||||
*/
|
||||
|
||||
clear_pass = clear;
|
||||
if (wipe_clear_pass && clear && *clear)
|
||||
strzero(clear);
|
||||
return retval;
|
||||
}
|
||||
|
||||
#ifdef AUTH_METHODS
|
||||
/*
|
||||
* _pw_auth - perform alternate password authentication
|
||||
*
|
||||
* pw_auth executes the alternate password authentication method
|
||||
* described in the user's password entry. _pw_auth does the real
|
||||
* work, pw_auth splits the authentication string into individual
|
||||
* command names.
|
||||
*/
|
||||
|
||||
static int
|
||||
_pw_auth(const char *command, const char *user, int reason, const char *input)
|
||||
{
|
||||
RETSIGTYPE (*sigint)();
|
||||
RETSIGTYPE (*sigquit)();
|
||||
#ifdef SIGTSTP
|
||||
RETSIGTYPE (*sigtstp)();
|
||||
#endif
|
||||
int pid;
|
||||
int status;
|
||||
int i;
|
||||
char * const argv[5];
|
||||
int argc = 0;
|
||||
int pipes[2];
|
||||
char *empty_env = NULL;
|
||||
int use_pipe;
|
||||
|
||||
/*
|
||||
* Start with a quick sanity check. ALL command names must
|
||||
* be fully-qualified path names.
|
||||
*/
|
||||
|
||||
if (command[0] != '/')
|
||||
return -1;
|
||||
|
||||
/*
|
||||
* Set the keyboard signals to be ignored. When the user kills
|
||||
* the child we don't want the parent dying as well.
|
||||
*/
|
||||
|
||||
sigint = signal (SIGINT, SIG_IGN);
|
||||
sigquit = signal (SIGQUIT, SIG_IGN);
|
||||
#ifdef SIGTSTP
|
||||
sigtstp = signal (SIGTSTP, SIG_IGN);
|
||||
#endif
|
||||
|
||||
/*
|
||||
* FTP and REXEC reasons don't give the program direct access
|
||||
* to the user. This means that the program can only get input
|
||||
* from this function. So we set up a pipe for that purpose.
|
||||
*/
|
||||
|
||||
use_pipe = (reason == PW_FTP || reason == PW_REXEC);
|
||||
if (use_pipe)
|
||||
if (pipe (pipes))
|
||||
return -1;
|
||||
|
||||
/*
|
||||
* The program will be forked off with the parent process waiting
|
||||
* on the child to tell it how successful it was.
|
||||
*/
|
||||
|
||||
switch (pid = fork ()) {
|
||||
|
||||
/*
|
||||
* The fork() failed completely. Clean up as needed and
|
||||
* return to the caller.
|
||||
*/
|
||||
case -1:
|
||||
if (use_pipe) {
|
||||
close (pipes[0]);
|
||||
close (pipes[1]);
|
||||
}
|
||||
return -1;
|
||||
case 0:
|
||||
|
||||
/*
|
||||
* Let the child catch the SIGINT and SIGQUIT
|
||||
* signals. The parent, however, will continue
|
||||
* to ignore them.
|
||||
*/
|
||||
signal (SIGINT, SIG_DFL);
|
||||
signal (SIGQUIT, SIG_DFL);
|
||||
|
||||
/*
|
||||
* Set up the command line. The first argument is
|
||||
* the name of the command being executed. The
|
||||
* second is the command line option for the reason,
|
||||
* and the third is the user name.
|
||||
*/
|
||||
argv[argc++] = command;
|
||||
switch (reason) {
|
||||
case PW_SU: argv[argc++] = "-s"; break;
|
||||
case PW_LOGIN: argv[argc++] = "-l"; break;
|
||||
case PW_ADD: argv[argc++] = "-a"; break;
|
||||
case PW_CHANGE: argv[argc++] = "-c"; break;
|
||||
case PW_DELETE: argv[argc++] = "-d"; break;
|
||||
case PW_TELNET: argv[argc++] = "-t"; break;
|
||||
case PW_RLOGIN: argv[argc++] = "-r"; break;
|
||||
case PW_FTP: argv[argc++] = "-f"; break;
|
||||
case PW_REXEC: argv[argc++] = "-x"; break;
|
||||
}
|
||||
if (reason == PW_CHANGE && input)
|
||||
argv[argc++] = input;
|
||||
|
||||
argv[argc++] = user;
|
||||
argv[argc] = (char *) 0;
|
||||
|
||||
/*
|
||||
* The FTP and REXEC reasons use a pipe to communicate
|
||||
* with the parent. The other standard I/O descriptors
|
||||
* are closed and re-opened as /dev/null.
|
||||
*/
|
||||
if (use_pipe) {
|
||||
close (0);
|
||||
close (1);
|
||||
close (2);
|
||||
|
||||
if (dup (pipes[0]) != 0)
|
||||
exit (1);
|
||||
|
||||
close (pipes[0]);
|
||||
close (pipes[1]);
|
||||
|
||||
if (open ("/dev/null", O_WRONLY) != 1)
|
||||
exit (1);
|
||||
|
||||
if (open ("/dev/null", O_WRONLY) != 2)
|
||||
exit (1);
|
||||
}
|
||||
|
||||
/*
|
||||
* Now we execute the command directly.
|
||||
* Do it with empty environment for safety. --marekm
|
||||
*/
|
||||
execve(command, argv, &empty_env);
|
||||
_exit((errno == ENOENT) ? 127 : 126);
|
||||
/*NOTREACHED*/
|
||||
default:
|
||||
/*
|
||||
* FTP and REXEC cause a single line of text to be
|
||||
* sent to the child over a pipe that was set up
|
||||
* earlier.
|
||||
*/
|
||||
if (use_pipe) {
|
||||
close (pipes[0]);
|
||||
|
||||
if (input)
|
||||
write (pipes[1], input, strlen (input));
|
||||
|
||||
write (pipes[1], "\n", 1);
|
||||
close (pipes[1]);
|
||||
}
|
||||
|
||||
/*
|
||||
* Wait on the child to die. When it does you will
|
||||
* get the exit status and use that to determine if
|
||||
* the authentication program was successful.
|
||||
*/
|
||||
while ((i = wait (&status)) != pid && i != -1)
|
||||
;
|
||||
|
||||
/*
|
||||
* Re-set the signals to their earlier values.
|
||||
*/
|
||||
signal (SIGINT, sigint);
|
||||
signal (SIGQUIT, sigquit);
|
||||
#ifdef SIGTSTP
|
||||
signal (SIGTSTP, sigtstp);
|
||||
#endif
|
||||
|
||||
/*
|
||||
* Make sure we found the right process!
|
||||
*/
|
||||
if (i == -1)
|
||||
return -1;
|
||||
|
||||
if (status == 0)
|
||||
return 0;
|
||||
else
|
||||
return -1;
|
||||
}
|
||||
/*NOTREACHED*/
|
||||
}
|
||||
|
||||
/*
|
||||
* _builtin_auth - lookup routine in table and execute
|
||||
*/
|
||||
|
||||
static int
|
||||
_builtin_auth(const char *command, const char *user, int reason, const char *input)
|
||||
{
|
||||
int i;
|
||||
|
||||
/*
|
||||
* Scan the table, looking for a match. If we fall off
|
||||
* the end, it must mean that this method isn't supported,
|
||||
* so we fail the authentication.
|
||||
*/
|
||||
|
||||
for (i = 0;methods[i].name[0];i++) {
|
||||
if (! strcmp (command, methods[i].name))
|
||||
break;
|
||||
}
|
||||
if (methods[i].name[0] == '\0')
|
||||
return -1;
|
||||
|
||||
/*
|
||||
* Call the pointed to function with the other three
|
||||
* arguments.
|
||||
*/
|
||||
|
||||
return (methods[i].func) (user, reason, input);
|
||||
}
|
||||
#endif /* AUTH_METHODS */
|
||||
|
||||
/*
|
||||
* This function does the real work. It splits the list of program names
|
||||
* up into individual programs and executes them one at a time.
|
||||
*/
|
||||
|
||||
int
|
||||
pw_auth(const char *command, const char *user, int reason, const char *input)
|
||||
{
|
||||
#ifdef AUTH_METHODS
|
||||
char buf[256];
|
||||
char *cmd, *end;
|
||||
int rc;
|
||||
|
||||
/*
|
||||
* Quick little sanity check ...
|
||||
*/
|
||||
|
||||
if (strlen (command) >= sizeof buf)
|
||||
return -1;
|
||||
|
||||
strcpy (buf, command); /* safe (because of the above check) --marekm */
|
||||
|
||||
/*
|
||||
* Find each command and make sure it is NUL-terminated. Then
|
||||
* invoke _pw_auth to actually run the program. The first
|
||||
* failing program ends the whole mess.
|
||||
*/
|
||||
|
||||
for (cmd = buf;cmd;cmd = end) {
|
||||
if ((end = strchr (cmd, ';')))
|
||||
*end++ = '\0';
|
||||
|
||||
if (cmd[0] != '@')
|
||||
rc = _old_auth (cmd, user, reason, input);
|
||||
else if (cmd[1] == '/')
|
||||
rc = _pw_auth (cmd + 1, user, reason, input);
|
||||
else
|
||||
rc = _builtin_auth (cmd + 1, user, reason, input);
|
||||
if (rc)
|
||||
return -1;
|
||||
}
|
||||
return 0;
|
||||
#else
|
||||
return _old_auth(command, user, reason, input);
|
||||
#endif
|
||||
}
|
||||
Reference in New Issue
Block a user