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/*
* Copyright (c) 1999-2005, 2008-2009 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* 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
__unused static const char rcsid[] = "$Sudo: sudo_auth.c,v 1.40 2009/05/25 12:02:42 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)
};
void
verify_user(pw, prompt)
struct passwd *pw;
char *prompt;
{
int counter = def_passwd_tries + 1;
int success = AUTH_FAILURE;
int status;
int flags;
char *p;
sudo_auth *auth;
sigaction_t sa, osa;
#ifdef HAVE_BSM_AUDIT
extern char **NewArgv;
#endif
/* 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) {
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "no authentication methods");
#endif
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)
SET(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)
CLR(auth->flags, FLAG_CONFIGURED);
else if (status == AUTH_FATAL) { /* XXX log */
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "authentication failure");
#endif
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)
CLR(auth->flags, FLAG_CONFIGURED);
else if (status == AUTH_FATAL) {/* XXX log */
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "authentication failure");
#endif
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 */
#ifdef AUTH_STANDALONE
p = prompt;
#else
p = (char *) tgetpass(prompt, def_passwd_timeout * 60,
tgetpass_flags);
#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)
zero_bytes(p, strlen(p));
#endif
if (!ISSET(tgetpass_flags, TGP_ASKPASS))
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 */
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "authentication failure");
#endif
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_INTR:
case AUTH_FAILURE:
if (counter != def_passwd_tries) {
if (def_mail_badpass || def_mail_always)
flags = 0;
else
flags = NO_MAIL;
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "authentication failure");
#endif
log_error(flags, "%d incorrect password attempt%s",
def_passwd_tries - counter,
(def_passwd_tries - counter == 1) ? "" : "s");
}
/* FALLTHROUGH */
case AUTH_FATAL:
#ifdef HAVE_BSM_AUDIT
audit_failure(NewArgv, "authentication failure");
#endif
exit(1);
}
/* NOTREACHED */
}
void
pass_warn(fp)
FILE *fp;
{
#ifdef INSULT
if (def_insults)
(void) fprintf(fp, "%s\n", INSULT);
else
#endif
(void) fprintf(fp, "%s\n", def_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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