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/*
* g_pw_in_tkt.c
*
* Copyright 1987, 1988 by the Massachusetts Institute of Technology.
*
* For copying and distribution information, please see the file
* <mit-copyright.h>.
*/
#include "mit-copyright.h"
#include "krb.h"
#include "krb_err.h"
#include "prot.h"
#include <string.h>
#ifndef NULL
#define NULL 0
#endif
#ifndef INTK_PW_NULL
#define INTK_PW_NULL KRBET_GT_PW_NULL
#endif
/*
* This file contains two routines: passwd_to_key() converts
* a password into a DES key (prompting for the password if
* not supplied), and krb_get_pw_in_tkt() gets an initial ticket for
* a user.
*/
/*
* passwd_to_key(): given a password, return a DES key.
* There are extra arguments here which (used to be?)
* used by srvtab_to_key().
*
* If the "passwd" argument is not null, generate a DES
* key from it, using string_to_key().
*
* If the "passwd" argument is null, then on a Unix system we call
* des_read_password() to prompt for a password and then convert it
* into a DES key. But "prompting" the user is harder in a Windows or
* Macintosh environment, so we rely on our caller to explicitly do
* that now.
*
* In either case, the resulting key is put in the "key" argument,
* and 0 is returned.
*/
/*ARGSUSED */
int
passwd_to_key(user,instance,realm,passwd,key)
char *user, *instance, *realm, *passwd;
C_Block key;
{
#if defined(_WINDOWS) || defined(macintosh)
string_to_key(passwd, key);
#else /* unix */
#ifdef NOENCRYPTION
if (!passwd)
placebo_read_password(key, "Password: ", 0);
#else /* Do encyryption */
if (passwd)
string_to_key(passwd, key);
else {
des_read_password(key, "Password: ", 0);
}
#endif /* NOENCRYPTION */
#endif /* unix */
return (0);
}
/*
* krb_get_pw_in_tkt() takes the name of the server for which the initial
* ticket is to be obtained, the name of the principal the ticket is
* for, the desired lifetime of the ticket, and the user's password.
* It passes its arguments on to krb_get_in_tkt(), which contacts
* Kerberos to get the ticket, decrypts it using the password provided,
* and stores it away for future use.
*
* On a Unix system, krb_get_pw_in_tkt() is able to prompt the user
* for a password, if the supplied password is null. On a a non Unix
* system, it now requires the caller to supply a non-null password.
* This is because of the complexities of prompting the user in a
* non-terminal-oriented environment like the Macintosh (running in a
* driver) or MS-Windows (in a DLL).
*
* krb_get_pw_in_tkt() passes two additional arguments to krb_get_in_tkt():
* the name of a routine (passwd_to_key()) to be used to get the
* password in case the "password" argument is null and NULL for the
* decryption procedure indicating that krb_get_in_tkt should use the
* default method of decrypting the response from the KDC.
*
* The result of the call to krb_get_in_tkt() is returned.
*/
KRB5_DLLIMP int KRB5_CALLCONV
krb_get_pw_in_tkt(user,instance,realm,service,sinstance,life,password)
char FAR *user, FAR *instance, FAR *realm, FAR *service, FAR *sinstance;
int life;
char FAR *password;
{
#if defined(_WINDOWS) || defined(macintosh)
/* In spite of the comments above, we don't allow that path here,
to simplify coding the non-UNIX clients. The only code that now
depends on this behavior is the preauth support, which has a
seperate function without this trap. Strictly speaking, this
is an API change. */
if (password == 0)
return INTK_PW_NULL;
#endif
return(krb_get_in_tkt(user,instance,realm,service,sinstance,life,
(key_proc_type)passwd_to_key,
(decrypt_tkt_type)NULL, password));
}
/*
* krb_get_pw_in_tkt_preauth() gets handed the password or key explicitly,
* since the whole point of "pre" authentication is to prove that we've
* already got the key, and the only way to do that is to ask the user
* for it. Clearly we shouldn't ask twice.
*/
static C_Block old_key;
static int stub_key(user,instance,realm,passwd,key)
char *user, *instance, *realm, *passwd;
C_Block key;
{
(void) memcpy((char *) key, (char *) old_key, sizeof(old_key));
return 0;
}
KRB5_DLLIMP int KRB5_CALLCONV
krb_get_pw_in_tkt_preauth(user,instance,realm,service,sinstance,life,password)
char FAR *user, FAR *instance, FAR *realm, FAR *service, FAR *sinstance;
int life;
char FAR *password;
{
char *preauth_p;
int preauth_len;
int ret_st;
#if defined(_WINDOWS) || defined(macintosh)
/* On non-Unix systems, we can't handle a null password, because
passwd_to_key can't handle prompting for the password. */
if (password == 0)
return INTK_PW_NULL;
#endif
krb_mk_preauth(&preauth_p, &preauth_len, (key_proc_type)passwd_to_key,
user, instance, realm, password, old_key);
ret_st = krb_get_in_tkt_preauth(user,instance,realm,service,sinstance,life,
(key_proc_type) stub_key,
(decrypt_tkt_type) NULL, password,
preauth_p, preauth_len);
krb_free_preauth(preauth_p, preauth_len);
return ret_st;
}
/* FIXME! This routine belongs in the krb library and should simply
be shared between the encrypted and NOENCRYPTION versions! */
#ifdef NOENCRYPTION
/*
* This routine prints the supplied string to standard
* output as a prompt, and reads a password string without
* echoing.
*/
#include <stdio.h>
#ifdef BSDUNIX
#include <string.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <setjmp.h>
#else
int strcmp();
#endif
#if defined(__svr4__) || defined(__SVR4)
#include <sgtty.h>
#endif
#ifdef BSDUNIX
static jmp_buf env;
#endif
#ifdef BSDUNIX
static void sig_restore();
static push_signals(), pop_signals();
int placebo_read_pw_string();
#endif
/*** Routines ****************************************************** */
int
placebo_read_password(k,prompt,verify)
des_cblock *k;
char *prompt;
int verify;
{
int ok;
char key_string[BUFSIZ];
#ifdef BSDUNIX
if (setjmp(env)) {
ok = -1;
goto lose;
}
#endif
ok = placebo_read_pw_string(key_string, BUFSIZ, prompt, verify);
if (ok == 0)
memset(k, 0, sizeof(C_Block));
lose:
memset(key_string, 0, sizeof (key_string));
return ok;
}
/*
* This version just returns the string, doesn't map to key.
*
* Returns 0 on success, non-zero on failure.
*/
int
placebo_read_pw_string(s,max,prompt,verify)
char *s;
int max;
char *prompt;
int verify;
{
int ok = 0;
char *ptr;
#ifdef BSDUNIX
jmp_buf old_env;
struct sgttyb tty_state;
#endif
char key_string[BUFSIZ];
if (max > BUFSIZ) {
return -1;
}
#ifdef BSDUNIX
memcpy(env, old_env, sizeof(env));
if (setjmp(env))
goto lose;
/* save terminal state */
if (ioctl(0,TIOCGETP,&tty_state) == -1)
return -1;
push_signals();
/* Turn off echo */
tty_state.sg_flags &= ~ECHO;
if (ioctl(0,TIOCSETP,&tty_state) == -1)
return -1;
#endif
while (!ok) {
printf(prompt);
fflush(stdout);
#ifdef CROSSMSDOS
h19line(s,sizeof(s),0);
if (!strlen(s))
continue;
#else
if (!fgets(s, max, stdin)) {
clearerr(stdin);
continue;
}
if ((ptr = strchr(s, '\n')))
*ptr = '\0';
#endif
if (verify) {
printf("\nVerifying, please re-enter %s",prompt);
fflush(stdout);
#ifdef CROSSMSDOS
h19line(key_string,sizeof(key_string),0);
if (!strlen(key_string))
continue;
#else
if (!fgets(key_string, sizeof(key_string), stdin)) {
clearerr(stdin);
continue;
}
if ((ptr = strchr(key_string, '\n')))
*ptr = '\0';
#endif
if (strcmp(s,key_string)) {
printf("\n\07\07Mismatch - try again\n");
fflush(stdout);
continue;
}
}
ok = 1;
}
#ifdef BSDUNIX
lose:
if (!ok)
memset(s, 0, max);
printf("\n");
/* turn echo back on */
tty_state.sg_flags |= ECHO;
if (ioctl(0,TIOCSETP,&tty_state))
ok = 0;
pop_signals();
memcpy(old_env, env, sizeof(env));
#endif
if (verify)
memset(key_string, 0, sizeof (key_string));
s[max-1] = 0; /* force termination */
return !ok; /* return nonzero if not okay */
}
#ifdef BSDUNIX
/*
* this can be static since we should never have more than
* one set saved....
*/
static sigtype (*old_sigfunc[NSIG])();
static push_signals()
{
register i;
for (i = 0; i < NSIG; i++)
old_sigfunc[i] = signal(i,sig_restore);
}
static pop_signals()
{
register i;
for (i = 0; i < NSIG; i++)
signal(i,old_sigfunc[i]);
}
static void sig_restore(sig,code,scp)
int sig,code;
struct sigcontext *scp;
{
longjmp(env,1);
}
#endif
#endif /* NOENCRYPTION */
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