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/*
* Copyright (c) 1999-2002 Todd C. Miller <Todd.Miller@courtesan.com>
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* 4. Products derived from this software may not be called "Sudo" nor
* may "Sudo" appear in their names without specific prior written
* permission from the author.
*
* THIS SOFTWARE IS PROVIDED ``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
* THE AUTHOR 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.
*
* Sponsored in part by the Defense Advanced Research Projects
* Agency (DARPA) and Air Force Research Laboratory, Air Force
* Materiel Command, USAF, under agreement number F39502-99-1-0512.
*/
#include "config.h"
#include <sys/types.h>
#include <sys/param.h>
#include <stdio.h>
#ifdef STDC_HEADERS
# include <stdlib.h>
# include <stddef.h>
#else
# ifdef HAVE_STDLIB_H
# include <stdlib.h>
# endif
#endif /* STDC_HEADERS */
#ifdef HAVE_STRING_H
# if defined(HAVE_MEMORY_H) && !defined(STDC_HEADERS)
# include <memory.h>
# endif
# include <string.h>
#else
# ifdef HAVE_STRINGS_H
# include <strings.h>
# endif
#endif /* HAVE_STRING_H */
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif /* HAVE_UNISTD_H */
#include <pwd.h>
#include <time.h>
#include <signal.h>
#include "sudo.h"
#include "sudo_auth.h"
#include "insults.h"
#ifndef lint
static const char rcsid[] = "$Sudo: sudo_auth.c,v 1.29 2003/04/16 00:42:10 millert Exp $";
#endif /* lint */
sudo_auth auth_switch[] = {
#ifdef AUTH_STANDALONE
AUTH_STANDALONE
#else
# ifndef WITHOUT_PASSWD
AUTH_ENTRY(0, "passwd", passwd_init, NULL, passwd_verify, NULL)
# endif
# if defined(HAVE_GETPRPWNAM) && !defined(WITHOUT_PASSWD)
AUTH_ENTRY(0, "secureware", secureware_init, NULL, secureware_verify, NULL)
# endif
# ifdef HAVE_AFS
AUTH_ENTRY(0, "afs", NULL, NULL, afs_verify, NULL)
# endif
# ifdef HAVE_DCE
AUTH_ENTRY(0, "dce", NULL, NULL, dce_verify, NULL)
# endif
# ifdef HAVE_KERB4
AUTH_ENTRY(0, "kerb4", kerb4_init, NULL, kerb4_verify, NULL)
# endif
# ifdef HAVE_KERB5
AUTH_ENTRY(0, "kerb5", kerb5_init, NULL, kerb5_verify, kerb5_cleanup)
# endif
# ifdef HAVE_SKEY
AUTH_ENTRY(0, "S/Key", NULL, rfc1938_setup, rfc1938_verify, NULL)
# endif
# ifdef HAVE_OPIE
AUTH_ENTRY(0, "OPIE", NULL, rfc1938_setup, rfc1938_verify, NULL)
# endif
#endif /* AUTH_STANDALONE */
AUTH_ENTRY(0, NULL, NULL, NULL, NULL, NULL)
};
int nil_pw; /* I hate resorting to globals like this... */
void
verify_user(pw, prompt)
struct passwd *pw;
char *prompt;
{
int counter = def_ival(I_PASSWD_TRIES) + 1;
int success = AUTH_FAILURE;
int status;
int flags;
volatile char *p;
sudo_auth *auth;
sigaction_t sa, osa;
/* Enable suspend during password entry. */
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
sa.sa_handler = SIG_DFL;
(void) sigaction(SIGTSTP, &sa, &osa);
/* Make sure we have at least one auth method. */
if (auth_switch[0].name == NULL)
log_error(0, "%s %s %s",
"There are no authentication methods compiled into sudo!",
"If you want to turn off authentication, use the",
"--disable-authentication configure option.");
/* Set FLAG_ONEANDONLY if there is only one auth method. */
if (auth_switch[1].name == NULL)
auth_switch[0].flags |= FLAG_ONEANDONLY;
/* Initialize auth methods and unconfigure the method if necessary. */
for (auth = auth_switch; auth->name; auth++) {
if (auth->init && IS_CONFIGURED(auth)) {
if (NEEDS_USER(auth))
set_perms(PERM_USER);
status = (auth->init)(pw, &prompt, auth);
if (status == AUTH_FAILURE)
auth->flags &= ~FLAG_CONFIGURED;
else if (status == AUTH_FATAL) /* XXX log */
exit(1); /* assume error msg already printed */
if (NEEDS_USER(auth))
set_perms(PERM_ROOT);
}
}
while (--counter) {
/* Do any per-method setup and unconfigure the method if needed */
for (auth = auth_switch; auth->name; auth++) {
if (auth->setup && IS_CONFIGURED(auth)) {
if (NEEDS_USER(auth))
set_perms(PERM_USER);
status = (auth->setup)(pw, &prompt, auth);
if (status == AUTH_FAILURE)
auth->flags &= ~FLAG_CONFIGURED;
else if (status == AUTH_FATAL) /* XXX log */
exit(1); /* assume error msg already printed */
if (NEEDS_USER(auth))
set_perms(PERM_ROOT);
}
}
/* Get the password unless the auth function will do it for us */
nil_pw = 0;
#ifdef AUTH_STANDALONE
p = prompt;
#else
p = (char *) tgetpass(prompt, def_ival(I_PASSWD_TIMEOUT) * 60,
tgetpass_flags);
if (!p || *p == '\0')
nil_pw = 1;
#endif /* AUTH_STANDALONE */
/* Call authentication functions. */
for (auth = auth_switch; p && auth->name; auth++) {
if (!IS_CONFIGURED(auth))
continue;
if (NEEDS_USER(auth))
set_perms(PERM_USER);
success = auth->status = (auth->verify)(pw, (char *)p, auth);
if (NEEDS_USER(auth))
set_perms(PERM_ROOT);
if (auth->status != AUTH_FAILURE)
goto cleanup;
}
#ifndef AUTH_STANDALONE
if (p)
(void) memset(p, 0, strlen(p));
#endif
/* Exit loop on nil password, but give it a chance to match first. */
if (nil_pw) {
if (counter == def_ival(I_PASSWD_TRIES))
exit(1);
else
break;
}
pass_warn(stderr);
}
cleanup:
/* Call cleanup routines. */
for (auth = auth_switch; auth->name; auth++) {
if (auth->cleanup && IS_CONFIGURED(auth)) {
if (NEEDS_USER(auth))
set_perms(PERM_USER);
status = (auth->cleanup)(pw, auth);
if (status == AUTH_FATAL) /* XXX log */
exit(1); /* assume error msg already printed */
if (NEEDS_USER(auth))
set_perms(PERM_ROOT);
}
}
switch (success) {
case AUTH_SUCCESS:
(void) sigaction(SIGTSTP, &osa, NULL);
return;
case AUTH_FAILURE:
if (def_flag(I_MAIL_BADPASS) || def_flag(I_MAIL_ALWAYS))
flags = 0;
else
flags = NO_MAIL;
log_error(flags, "%d incorrect password attempt%s",
def_ival(I_PASSWD_TRIES) - counter,
(def_ival(I_PASSWD_TRIES) - counter == 1) ? "" : "s");
case AUTH_FATAL:
exit(1);
}
/* NOTREACHED */
}
void
pass_warn(fp)
FILE *fp;
{
#ifdef INSULT
if (def_flag(I_INSULTS))
(void) fprintf(fp, "%s\n", INSULT);
else
#endif
(void) fprintf(fp, "%s\n", def_str(I_BADPASS_MESSAGE));
}
void
dump_auth_methods()
{
sudo_auth *auth;
(void) fputs("Authentication methods:", stdout);
for (auth = auth_switch; auth->name; auth++)
(void) printf(" '%s'", auth->name);
(void) putchar('\n');
}
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