4.4BSD/usr/src/lib/libtelnet/krb4encpwd.c
/*-
* Copyright (c) 1992, 1993
* The Regents of the University of California. 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 THE REGENTS 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 THE REGENTS 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.
*/
#ifndef lint
static char sccsid[] = "@(#)krb4encpwd.c 8.1 (Berkeley) 6/4/93";
#endif /* not lint */
#ifdef KRB4_ENCPWD
/*
* COPYRIGHT (C) 1990 DIGITAL EQUIPMENT CORPORATION
* ALL RIGHTS RESERVED
*
* "Digital Equipment Corporation authorizes the reproduction,
* distribution and modification of this software subject to the following
* restrictions:
*
* 1. Any partial or whole copy of this software, or any modification
* thereof, must include this copyright notice in its entirety.
*
* 2. This software is supplied "as is" with no warranty of any kind,
* expressed or implied, for any purpose, including any warranty of fitness
* or merchantibility. DIGITAL assumes no responsibility for the use or
* reliability of this software, nor promises to provide any form of
* support for it on any basis.
*
* 3. Distribution of this software is authorized only if no profit or
* remuneration of any kind is received in exchange for such distribution.
*
* 4. This software produces public key authentication certificates
* bearing an expiration date established by DIGITAL and RSA Data
* Security, Inc. It may cease to generate certificates after the expiration
* date. Any modification of this software that changes or defeats
* the expiration date or its effect is unauthorized.
*
* 5. Software that will renew or extend the expiration date of
* authentication certificates produced by this software may be obtained
* from RSA Data Security, Inc., 10 Twin Dolphin Drive, Redwood City, CA
* 94065, (415)595-8782, or from DIGITAL"
*
*/
#include <sys/types.h>
#include <arpa/telnet.h>
#include <pwd.h>
#include <stdio.h>
#include <des.h>
#include <krb.h>
#ifdef __STDC__
#include <stdlib.h>
#endif
#ifdef NO_STRING_H
#include <strings.h>
#else
#include <string.h>
#endif
#include "encrypt.h"
#include "auth.h"
#include "misc.h"
int krb_mk_encpwd_req P((KTEXT, char *, char *, char *, char *, char *, char *));
int krb_rd_encpwd_req P((KTEXT, char *, char *, u_long, AUTH_DAT *, char *, char *, char *, char *));
extern auth_debug_mode;
static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0,
AUTHTYPE_KRB4_ENCPWD, };
static unsigned char str_name[1024] = { IAC, SB, TELOPT_AUTHENTICATION,
TELQUAL_NAME, };
#define KRB4_ENCPWD_AUTH 0 /* Authentication data follows */
#define KRB4_ENCPWD_REJECT 1 /* Rejected (reason might follow) */
#define KRB4_ENCPWD_ACCEPT 2 /* Accepted */
#define KRB4_ENCPWD_CHALLENGE 3 /* Challenge for mutual auth. */
#define KRB4_ENCPWD_ACK 4 /* Acknowledge */
#define KRB_SERVICE_NAME "rcmd"
static KTEXT_ST auth;
static char name[ANAME_SZ];
static char user_passwd[ANAME_SZ];
static AUTH_DAT adat = { 0 };
static Schedule sched;
static char challenge[REALM_SZ];
static int
Data(ap, type, d, c)
Authenticator *ap;
int type;
void *d;
int c;
{
unsigned char *p = str_data + 4;
unsigned char *cd = (unsigned char *)d;
if (c == -1)
c = strlen((char *)cd);
if (0) {
printf("%s:%d: [%d] (%d)",
str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY",
str_data[3],
type, c);
printd(d, c);
printf("\r\n");
}
*p++ = ap->type;
*p++ = ap->way;
*p++ = type;
while (c-- > 0) {
if ((*p++ = *cd++) == IAC)
*p++ = IAC;
}
*p++ = IAC;
*p++ = SE;
if (str_data[3] == TELQUAL_IS)
printsub('>', &str_data[2], p - (&str_data[2]));
return(net_write(str_data, p - str_data));
}
int
krb4encpwd_init(ap, server)
Authenticator *ap;
int server;
{
char hostname[80], *cp, *realm;
C_Block skey;
if (server) {
str_data[3] = TELQUAL_REPLY;
} else {
str_data[3] = TELQUAL_IS;
gethostname(hostname, sizeof(hostname));
realm = krb_realmofhost(hostname);
cp = index(hostname, '.');
if (*cp != NULL) *cp = NULL;
if (read_service_key(KRB_SERVICE_NAME, hostname, realm, 0,
KEYFILE, (char *)skey)) {
return(0);
}
}
return(1);
}
int
krb4encpwd_send(ap)
Authenticator *ap;
{
printf("[ Trying KRB4ENCPWD ... ]\n");
if (!UserNameRequested) {
return(0);
}
if (!auth_sendname(UserNameRequested, strlen(UserNameRequested))) {
return(0);
}
if (!Data(ap, KRB4_ENCPWD_ACK, (void *)NULL, 0)) {
return(0);
}
return(1);
}
void
krb4encpwd_is(ap, data, cnt)
Authenticator *ap;
unsigned char *data;
int cnt;
{
Session_Key skey;
Block datablock;
char r_passwd[ANAME_SZ], r_user[ANAME_SZ];
char lhostname[ANAME_SZ], *cp;
int r;
time_t now;
if (cnt-- < 1)
return;
switch (*data++) {
case KRB4_ENCPWD_AUTH:
bcopy((void *)data, (void *)auth.dat, auth.length = cnt);
gethostname(lhostname, sizeof(lhostname));
if ((cp = index(lhostname, '.')) != 0) *cp = '\0';
if (r = krb_rd_encpwd_req(&auth, KRB_SERVICE_NAME, lhostname, 0, &adat, NULL, challenge, r_user, r_passwd)) {
Data(ap, KRB4_ENCPWD_REJECT, (void *)"Auth failed", -1);
auth_finished(ap, AUTH_REJECT);
return;
}
auth_encrypt_userpwd(r_passwd);
if (passwdok(UserNameRequested, UserPassword) == 0) {
/*
* illegal username and password
*/
Data(ap, KRB4_ENCPWD_REJECT, (void *)"Illegal password", -1);
auth_finished(ap, AUTH_REJECT);
return;
}
bcopy((void *)adat.session, (void *)session_key, sizeof(Block));
Data(ap, KRB4_ENCPWD_ACCEPT, (void *)0, 0);
auth_finished(ap, AUTH_USER);
break;
case KRB4_ENCPWD_CHALLENGE:
/*
* Take the received random challenge text and save
* for future authentication.
*/
bcopy((void *)data, (void *)challenge, sizeof(Block));
break;
case KRB4_ENCPWD_ACK:
/*
* Receive ack, if mutual then send random challenge
*/
/*
* If we are doing mutual authentication, get set up to send
* the challange, and verify it when the response comes back.
*/
if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
register int i;
time(&now);
sprintf(challenge, "%x", now);
Data(ap, KRB4_ENCPWD_CHALLENGE, (void *)challenge, strlen(challenge));
}
break;
default:
Data(ap, KRB4_ENCPWD_REJECT, 0, 0);
break;
}
}
void
krb4encpwd_reply(ap, data, cnt)
Authenticator *ap;
unsigned char *data;
int cnt;
{
Session_Key skey;
KTEXT_ST krb_token;
Block enckey;
CREDENTIALS cred;
int r;
char randchal[REALM_SZ], instance[ANAME_SZ], *cp;
char hostname[80], *realm;
if (cnt-- < 1)
return;
switch (*data++) {
case KRB4_ENCPWD_REJECT:
if (cnt > 0) {
printf("[ KRB4_ENCPWD refuses authentication because %.*s ]\r\n",
cnt, data);
} else
printf("[ KRB4_ENCPWD refuses authentication ]\r\n");
auth_send_retry();
return;
case KRB4_ENCPWD_ACCEPT:
printf("[ KRB4_ENCPWD accepts you ]\n");
auth_finished(ap, AUTH_USER);
return;
case KRB4_ENCPWD_CHALLENGE:
/*
* Verify that the response to the challenge is correct.
*/
gethostname(hostname, sizeof(hostname));
realm = krb_realmofhost(hostname);
bcopy((void *)data, (void *)challenge, cnt);
bzero(user_passwd, sizeof(user_passwd));
local_des_read_pw_string(user_passwd, sizeof(user_passwd)-1, "Password: ", 0);
UserPassword = user_passwd;
Challenge = challenge;
strcpy(instance, RemoteHostName);
if ((cp = index(instance, '.')) != 0) *cp = '\0';
if (r = krb_mk_encpwd_req(&krb_token, KRB_SERVICE_NAME, instance, realm, Challenge, UserNameRequested, user_passwd)) {
krb_token.length = 0;
}
if (!Data(ap, KRB4_ENCPWD_AUTH, (void *)krb_token.dat, krb_token.length)) {
return;
}
break;
default:
return;
}
}
int
krb4encpwd_status(ap, name, level)
Authenticator *ap;
char *name;
int level;
{
if (level < AUTH_USER)
return(level);
if (UserNameRequested && passwdok(UserNameRequested, UserPassword)) {
strcpy(name, UserNameRequested);
return(AUTH_VALID);
} else {
return(AUTH_USER);
}
}
#define BUMP(buf, len) while (*(buf)) {++(buf), --(len);}
#define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);}
void
krb4encpwd_printsub(data, cnt, buf, buflen)
unsigned char *data, *buf;
int cnt, buflen;
{
char lbuf[32];
register int i;
buf[buflen-1] = '\0'; /* make sure its NULL terminated */
buflen -= 1;
switch(data[3]) {
case KRB4_ENCPWD_REJECT: /* Rejected (reason might follow) */
strncpy((char *)buf, " REJECT ", buflen);
goto common;
case KRB4_ENCPWD_ACCEPT: /* Accepted (name might follow) */
strncpy((char *)buf, " ACCEPT ", buflen);
common:
BUMP(buf, buflen);
if (cnt <= 4)
break;
ADDC(buf, buflen, '"');
for (i = 4; i < cnt; i++)
ADDC(buf, buflen, data[i]);
ADDC(buf, buflen, '"');
ADDC(buf, buflen, '\0');
break;
case KRB4_ENCPWD_AUTH: /* Authentication data follows */
strncpy((char *)buf, " AUTH", buflen);
goto common2;
case KRB4_ENCPWD_CHALLENGE:
strncpy((char *)buf, " CHALLENGE", buflen);
goto common2;
case KRB4_ENCPWD_ACK:
strncpy((char *)buf, " ACK", buflen);
goto common2;
default:
sprintf(lbuf, " %d (unknown)", data[3]);
strncpy((char *)buf, lbuf, buflen);
common2:
BUMP(buf, buflen);
for (i = 4; i < cnt; i++) {
sprintf(lbuf, " %d", data[i]);
strncpy((char *)buf, lbuf, buflen);
BUMP(buf, buflen);
}
break;
}
}
int passwdok(name, passwd)
char *name, *passwd;
{
char *crypt();
char *salt, *p;
struct passwd *pwd;
int passwdok_status = 0;
if (pwd = getpwnam(name))
salt = pwd->pw_passwd;
else salt = "xx";
p = crypt(passwd, salt);
if (pwd && !strcmp(p, pwd->pw_passwd)) {
passwdok_status = 1;
} else passwdok_status = 0;
return(passwdok_status);
}
#endif
#ifdef notdef
prkey(msg, key)
char *msg;
unsigned char *key;
{
register int i;
printf("%s:", msg);
for (i = 0; i < 8; i++)
printf(" %3d", key[i]);
printf("\r\n");
}
#endif