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kerberos5.c revision 1.21
      1  1.21       mrg /*	$NetBSD: kerberos5.c,v 1.21 2021/04/12 09:17:48 mrg Exp $	*/
      2   1.4   thorpej 
      3   1.1       cgd /*-
      4   1.4   thorpej  * Copyright (c) 1991, 1993
      5   1.4   thorpej  *	The Regents of the University of California.  All rights reserved.
      6   1.1       cgd  *
      7   1.1       cgd  * Redistribution and use in source and binary forms, with or without
      8   1.1       cgd  * modification, are permitted provided that the following conditions
      9   1.1       cgd  * are met:
     10   1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     11   1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     12   1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     14   1.1       cgd  *    documentation and/or other materials provided with the distribution.
     15  1.12       agc  * 3. Neither the name of the University nor the names of its contributors
     16   1.1       cgd  *    may be used to endorse or promote products derived from this software
     17   1.1       cgd  *    without specific prior written permission.
     18   1.1       cgd  *
     19   1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20   1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21   1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22   1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23   1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24   1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25   1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26   1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27   1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28   1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29   1.1       cgd  * SUCH DAMAGE.
     30   1.1       cgd  */
     31   1.1       cgd 
     32   1.1       cgd /*
     33   1.1       cgd  * Copyright (C) 1990 by the Massachusetts Institute of Technology
     34   1.1       cgd  *
     35   1.4   thorpej  * Export of this software from the United States of America may
     36   1.4   thorpej  * require a specific license from the United States Government.
     37   1.1       cgd  * It is the responsibility of any person or organization contemplating
     38   1.1       cgd  * export to obtain such a license before exporting.
     39   1.1       cgd  *
     40   1.1       cgd  * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
     41   1.1       cgd  * distribute this software and its documentation for any purpose and
     42   1.1       cgd  * without fee is hereby granted, provided that the above copyright
     43   1.1       cgd  * notice appear in all copies and that both that copyright notice and
     44   1.1       cgd  * this permission notice appear in supporting documentation, and that
     45   1.1       cgd  * the name of M.I.T. not be used in advertising or publicity pertaining
     46   1.1       cgd  * to distribution of the software without specific, written prior
     47   1.1       cgd  * permission.  M.I.T. makes no representations about the suitability of
     48   1.1       cgd  * this software for any purpose.  It is provided "as is" without express
     49   1.1       cgd  * or implied warranty.
     50   1.1       cgd  */
     51   1.1       cgd 
     52   1.1       cgd #ifdef	KRB5
     53   1.1       cgd #include <arpa/telnet.h>
     54   1.1       cgd #include <stdio.h>
     55   1.4   thorpej #include <stdlib.h>
     56   1.4   thorpej #include <string.h>
     57   1.4   thorpej #include <unistd.h>
     58   1.1       cgd #include <netdb.h>
     59   1.1       cgd #include <ctype.h>
     60   1.4   thorpej #include <pwd.h>
     61   1.4   thorpej #define Authenticator k5_Authenticator
     62   1.4   thorpej #include <krb5.h>
     63   1.4   thorpej #undef Authenticator
     64   1.4   thorpej /* #include <roken.h> */
     65   1.1       cgd 
     66   1.1       cgd #include "encrypt.h"
     67   1.1       cgd #include "auth.h"
     68   1.1       cgd #include "misc.h"
     69   1.1       cgd 
     70   1.6  christos extern int net;
     71   1.6  christos 
     72   1.4   thorpej int forward_flags;	/* Flags get set in telnet/main.c on -f and -F */
     73   1.4   thorpej int got_forwarded_creds;/* Tell telnetd to pass -F or -f to login. */
     74   1.1       cgd 
     75   1.4   thorpej int require_hwpreauth;
     76   1.1       cgd 
     77  1.18     elric const char *get_krb5_err_text(krb5_context, krb5_error_code);
     78   1.4   thorpej void kerberos5_forward(Authenticator *);
     79   1.4   thorpej 
     80   1.4   thorpej static unsigned char str_data[1024] = {IAC, SB, TELOPT_AUTHENTICATION, 0,
     81   1.4   thorpej 				       AUTHTYPE_KERBEROS_V5,};
     82   1.4   thorpej 
     83   1.4   thorpej #define	KRB_AUTH		0	/* Authentication data follows */
     84   1.4   thorpej #define	KRB_REJECT		1	/* Rejected (reason might follow) */
     85   1.4   thorpej #define	KRB_ACCEPT		2	/* Accepted */
     86   1.4   thorpej #define	KRB_RESPONSE		3	/* Response for mutual auth. */
     87   1.4   thorpej 
     88   1.4   thorpej #define KRB_FORWARD     	4	/* Forwarded credentials follow */
     89   1.4   thorpej #define KRB_FORWARD_ACCEPT     	5	/* Forwarded credentials accepted */
     90   1.4   thorpej #define KRB_FORWARD_REJECT     	6	/* Forwarded credentials rejected */
     91   1.4   thorpej 
     92   1.4   thorpej static krb5_data auth;
     93   1.4   thorpej static krb5_ticket *ticket;
     94   1.4   thorpej 
     95   1.4   thorpej krb5_context telnet_context;
     96   1.4   thorpej static krb5_auth_context auth_context;
     97   1.4   thorpej 
     98   1.4   thorpej static int
     99  1.19  christos Data(Authenticator *ap, int type, const void *d, int c)
    100   1.1       cgd {
    101   1.4   thorpej 	unsigned char *p = str_data + 4;
    102  1.19  christos 	const unsigned char *cd = (const unsigned char *) d;
    103   1.1       cgd 
    104   1.1       cgd 	if (c == -1)
    105   1.4   thorpej 		c = strlen(cd);
    106   1.1       cgd 
    107   1.4   thorpej 	if (auth_debug_mode) {
    108   1.4   thorpej 		printf("%s:%d: [%d] (%d)",
    109   1.4   thorpej 		    str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY",
    110   1.4   thorpej 		    str_data[3],
    111   1.4   thorpej 		    type, c);
    112   1.4   thorpej 		printd(d, c);
    113   1.4   thorpej 		printf("\r\n");
    114   1.4   thorpej 	}
    115   1.1       cgd 	*p++ = ap->type;
    116   1.1       cgd 	*p++ = ap->way;
    117   1.1       cgd 	*p++ = type;
    118   1.4   thorpej 	while (c-- > 0) {
    119   1.4   thorpej 		if ((*p++ = *cd++) == IAC)
    120   1.4   thorpej 			*p++ = IAC;
    121   1.4   thorpej 	}
    122   1.4   thorpej 	*p++ = IAC;
    123   1.4   thorpej 	*p++ = SE;
    124   1.1       cgd 	if (str_data[3] == TELQUAL_IS)
    125   1.1       cgd 		printsub('>', &str_data[2], p - &str_data[2]);
    126   1.4   thorpej 	return (telnet_net_write(str_data, p - str_data));
    127   1.1       cgd }
    128   1.1       cgd 
    129  1.18     elric const char *
    130  1.18     elric get_krb5_err_text(krb5_context ctx, krb5_error_code ret)
    131  1.18     elric {
    132  1.18     elric 	static const char	*str = NULL;
    133  1.18     elric 
    134  1.18     elric 	if (str)
    135  1.18     elric 		krb5_free_error_message(ctx, str);
    136  1.18     elric 
    137  1.18     elric 	str = krb5_get_error_message(ctx, ret);
    138  1.18     elric 
    139  1.18     elric 	if (str != NULL)
    140  1.18     elric 		return str;
    141  1.18     elric 
    142  1.18     elric 	return "unknown";
    143  1.18     elric }
    144  1.18     elric 
    145   1.4   thorpej int
    146   1.4   thorpej kerberos5_init(Authenticator *ap, int server)
    147   1.1       cgd {
    148   1.5   thorpej 	krb5_error_code ret;
    149   1.4   thorpej 
    150   1.5   thorpej 	if (telnet_context == 0) {
    151   1.5   thorpej 		ret = krb5_init_context(&telnet_context);
    152   1.5   thorpej 		if (ret)
    153   1.5   thorpej 			return 0;
    154   1.5   thorpej 	}
    155   1.4   thorpej 
    156   1.4   thorpej 	if (server) {
    157   1.4   thorpej 		krb5_keytab kt;
    158   1.4   thorpej 		krb5_kt_cursor cursor;
    159   1.4   thorpej 
    160   1.4   thorpej 		ret = krb5_kt_default(telnet_context, &kt);
    161   1.4   thorpej 		if (ret)
    162   1.4   thorpej 			return 0;
    163   1.4   thorpej 
    164   1.4   thorpej 		ret = krb5_kt_start_seq_get(telnet_context, kt, &cursor);
    165   1.4   thorpej 		if (ret) {
    166   1.4   thorpej 			krb5_kt_close(telnet_context, kt);
    167   1.4   thorpej 			return 0;
    168   1.4   thorpej 		}
    169   1.4   thorpej 		krb5_kt_end_seq_get(telnet_context, kt, &cursor);
    170   1.4   thorpej 		krb5_kt_close(telnet_context, kt);
    171   1.4   thorpej 
    172   1.1       cgd 		str_data[3] = TELQUAL_REPLY;
    173   1.4   thorpej 	} else
    174   1.1       cgd 		str_data[3] = TELQUAL_IS;
    175   1.4   thorpej 	return (1);
    176   1.1       cgd }
    177   1.1       cgd 
    178   1.4   thorpej int
    179   1.4   thorpej kerberos5_send(Authenticator *ap)
    180   1.1       cgd {
    181   1.4   thorpej 	krb5_error_code ret;
    182   1.1       cgd 	krb5_ccache ccache;
    183   1.4   thorpej 	int ap_opts;
    184   1.4   thorpej 	krb5_data cksum_data;
    185   1.4   thorpej 	char foo[2];
    186   1.1       cgd 
    187   1.4   thorpej 	printf("[ Trying KERBEROS5 ... ]\r\n");
    188   1.1       cgd 
    189   1.4   thorpej 	if (!UserNameRequested) {
    190   1.1       cgd 		if (auth_debug_mode) {
    191   1.4   thorpej 			printf("Kerberos V5: no user name supplied\r\n");
    192   1.1       cgd 		}
    193   1.4   thorpej 		return (0);
    194   1.1       cgd 	}
    195   1.4   thorpej 	ret = krb5_cc_default(telnet_context, &ccache);
    196   1.4   thorpej 	if (ret) {
    197   1.1       cgd 		if (auth_debug_mode) {
    198   1.4   thorpej 			printf(
    199   1.4   thorpej 			"Kerberos V5: could not get default ccache: %s\r\n",
    200  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    201   1.1       cgd 		}
    202   1.4   thorpej 		return (0);
    203   1.1       cgd 	}
    204   1.4   thorpej 	if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL)
    205   1.4   thorpej 		ap_opts = AP_OPTS_MUTUAL_REQUIRED;
    206   1.4   thorpej 	else
    207   1.4   thorpej 		ap_opts = 0;
    208   1.1       cgd 
    209   1.9      joda 	ap_opts |= AP_OPTS_USE_SUBKEY;
    210   1.9      joda 
    211   1.4   thorpej 	ret = krb5_auth_con_init(telnet_context, &auth_context);
    212   1.4   thorpej 	if (ret) {
    213   1.1       cgd 		if (auth_debug_mode) {
    214   1.4   thorpej 			printf(
    215   1.4   thorpej 			"Kerberos V5: krb5_auth_con_init failed: %s\r\n",
    216  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    217   1.4   thorpej 		}
    218   1.4   thorpej 		return (0);
    219   1.4   thorpej 	}
    220   1.4   thorpej 	ret = krb5_auth_con_setaddrs_from_fd(telnet_context,
    221   1.4   thorpej 	    auth_context, &net);
    222   1.4   thorpej 	if (ret) {
    223   1.4   thorpej 		if (auth_debug_mode) {
    224   1.4   thorpej 			printf("Kerberos V5: "
    225   1.4   thorpej 			    "krb5_auth_con_setaddrs_from_fd failed: %s\r\n",
    226  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    227   1.1       cgd 		}
    228   1.4   thorpej 		return (0);
    229   1.1       cgd 	}
    230  1.20     joerg 	krb5_auth_con_setkeytype(telnet_context, auth_context,
    231  1.21       mrg 	    KRB5_ENCTYPE_DES_CBC_CRC);
    232   1.1       cgd 
    233   1.4   thorpej 	foo[0] = ap->type;
    234   1.4   thorpej 	foo[1] = ap->way;
    235   1.1       cgd 
    236   1.4   thorpej 	cksum_data.length = sizeof(foo);
    237   1.4   thorpej 	cksum_data.data = foo;
    238   1.4   thorpej 	ret = krb5_mk_req(telnet_context, &auth_context, ap_opts, "host",
    239   1.4   thorpej 	    RemoteHostName, &cksum_data, ccache, &auth);
    240   1.4   thorpej 	if (ret) {
    241   1.4   thorpej 		if (1 || auth_debug_mode) {
    242   1.4   thorpej 			printf("Kerberos V5: mk_req failed (%s)\r\n",
    243  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    244   1.1       cgd 		}
    245   1.4   thorpej 		return (0);
    246   1.1       cgd 	}
    247   1.1       cgd 
    248   1.4   thorpej 	if (!auth_sendname((unsigned char *) UserNameRequested,
    249   1.4   thorpej 		strlen(UserNameRequested))) {
    250   1.4   thorpej 		if (auth_debug_mode)
    251   1.4   thorpej 			printf("Not enough room for user name\r\n");
    252   1.4   thorpej 		return (0);
    253   1.4   thorpej 	}
    254   1.1       cgd 	if (!Data(ap, KRB_AUTH, auth.data, auth.length)) {
    255   1.1       cgd 		if (auth_debug_mode)
    256   1.1       cgd 			printf("Not enough room for authentication data\r\n");
    257   1.4   thorpej 		return (0);
    258   1.1       cgd 	}
    259   1.1       cgd 	if (auth_debug_mode) {
    260   1.1       cgd 		printf("Sent Kerberos V5 credentials to server\r\n");
    261   1.1       cgd 	}
    262   1.4   thorpej 	return (1);
    263   1.1       cgd }
    264   1.1       cgd 
    265   1.4   thorpej void
    266   1.4   thorpej kerberos5_is(Authenticator * ap, unsigned char *data, int cnt)
    267   1.1       cgd {
    268   1.4   thorpej 	krb5_error_code ret;
    269   1.4   thorpej 	krb5_data outbuf;
    270   1.4   thorpej 	krb5_keyblock *key_block;
    271   1.1       cgd 	char *name;
    272   1.4   thorpej 	krb5_principal server;
    273   1.4   thorpej 	int zero = 0;
    274   1.1       cgd 
    275   1.1       cgd 	if (cnt-- < 1)
    276   1.1       cgd 		return;
    277   1.1       cgd 	switch (*data++) {
    278   1.1       cgd 	case KRB_AUTH:
    279   1.4   thorpej 		auth.data = (char *) data;
    280   1.1       cgd 		auth.length = cnt;
    281   1.1       cgd 
    282   1.4   thorpej 		auth_context = NULL;
    283   1.4   thorpej 
    284   1.4   thorpej 		ret = krb5_auth_con_init(telnet_context, &auth_context);
    285   1.4   thorpej 		if (ret) {
    286   1.4   thorpej 			Data(ap, KRB_REJECT, "krb5_auth_con_init failed", -1);
    287   1.4   thorpej 			auth_finished(ap, AUTH_REJECT);
    288   1.1       cgd 			if (auth_debug_mode)
    289   1.4   thorpej 				printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
    290  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    291   1.4   thorpej 			return;
    292   1.4   thorpej 		}
    293   1.4   thorpej 		ret = krb5_auth_con_setaddrs_from_fd(telnet_context,
    294   1.4   thorpej 		    auth_context, &zero);
    295   1.4   thorpej 		if (ret) {
    296   1.4   thorpej 			Data(ap, KRB_REJECT, "krb5_auth_con_setaddrs_from_fd failed", -1);
    297   1.1       cgd 			auth_finished(ap, AUTH_REJECT);
    298   1.4   thorpej 			if (auth_debug_mode)
    299   1.4   thorpej 				printf("Kerberos V5: "
    300   1.4   thorpej 				    "krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
    301  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    302   1.1       cgd 			return;
    303   1.1       cgd 		}
    304   1.4   thorpej 		ret = krb5_sock_to_principal(telnet_context, 0, "host",
    305   1.4   thorpej 		    KRB5_NT_SRV_HST, &server);
    306   1.4   thorpej 		if (ret) {
    307   1.4   thorpej 			Data(ap, KRB_REJECT, "krb5_sock_to_principal failed", -1);
    308   1.4   thorpej 			auth_finished(ap, AUTH_REJECT);
    309   1.1       cgd 			if (auth_debug_mode)
    310   1.4   thorpej 				printf("Kerberos V5: "
    311   1.4   thorpej 				    "krb5_sock_to_principal failed (%s)\r\n",
    312  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    313   1.1       cgd 			return;
    314   1.1       cgd 		}
    315   1.4   thorpej 		ret = krb5_rd_req(telnet_context, &auth_context, &auth,
    316   1.4   thorpej 		    server, NULL, NULL, &ticket);
    317   1.4   thorpej 		krb5_free_principal(telnet_context, server);
    318   1.4   thorpej 
    319   1.4   thorpej 		if (ret) {
    320   1.4   thorpej 			char *errbuf;
    321   1.4   thorpej 
    322   1.4   thorpej 			asprintf(&errbuf,
    323   1.4   thorpej 			    "Read req failed: %s",
    324  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    325   1.4   thorpej 			Data(ap, KRB_REJECT, errbuf, -1);
    326   1.1       cgd 			if (auth_debug_mode)
    327   1.4   thorpej 				printf("%s\r\n", errbuf);
    328   1.4   thorpej 			free(errbuf);
    329   1.1       cgd 			return;
    330   1.4   thorpej 		} {
    331   1.4   thorpej 			char foo[2];
    332   1.4   thorpej 
    333   1.4   thorpej 			foo[0] = ap->type;
    334   1.4   thorpej 			foo[1] = ap->way;
    335   1.4   thorpej 
    336   1.4   thorpej 			ret = krb5_verify_authenticator_checksum(telnet_context,
    337   1.4   thorpej 			    auth_context, foo, sizeof(foo));
    338   1.4   thorpej 
    339   1.4   thorpej 			if (ret) {
    340   1.4   thorpej 				char *errbuf;
    341   1.4   thorpej 				asprintf(&errbuf, "Bad checksum: %s",
    342  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    343   1.4   thorpej 				Data(ap, KRB_REJECT, errbuf, -1);
    344   1.4   thorpej 				if (auth_debug_mode)
    345   1.4   thorpej 					printf("%s\r\n", errbuf);
    346   1.4   thorpej 				free(errbuf);
    347   1.4   thorpej 				return;
    348   1.4   thorpej 			}
    349   1.1       cgd 		}
    350   1.4   thorpej 		ret = krb5_auth_con_getremotesubkey(telnet_context,
    351   1.4   thorpej 		    auth_context, &key_block);
    352   1.1       cgd 
    353   1.4   thorpej 		if (ret) {
    354   1.4   thorpej 			Data(ap, KRB_REJECT, "krb5_auth_con_getremotesubkey failed", -1);
    355   1.4   thorpej 			auth_finished(ap, AUTH_REJECT);
    356   1.1       cgd 			if (auth_debug_mode)
    357   1.4   thorpej 				printf("Kerberos V5: "
    358   1.4   thorpej 				    "krb5_auth_con_getremotesubkey failed (%s)\r\n",
    359  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    360   1.9      joda 			return;
    361   1.9      joda 		}
    362   1.9      joda 		if (key_block == NULL) {
    363  1.10   thorpej 			ret = krb5_auth_con_getkey(telnet_context,
    364   1.9      joda 						   auth_context,
    365   1.9      joda 						   &key_block);
    366   1.9      joda 		}
    367   1.9      joda 		if (ret) {
    368   1.9      joda 			Data(ap, KRB_REJECT, "krb5_auth_con_getkey failed", -1);
    369   1.9      joda 			auth_finished(ap, AUTH_REJECT);
    370   1.9      joda 			if (auth_debug_mode)
    371   1.9      joda 				printf("Kerberos V5: "
    372   1.9      joda 				       "krb5_auth_con_getkey failed (%s)\r\n",
    373  1.18     elric 				       get_krb5_err_text(telnet_context, ret));
    374   1.9      joda 			return;
    375   1.9      joda 		}
    376   1.9      joda 		if (key_block == NULL) {
    377   1.9      joda 			Data(ap, KRB_REJECT, "no subkey received", -1);
    378   1.9      joda 			auth_finished(ap, AUTH_REJECT);
    379   1.9      joda 			if (auth_debug_mode)
    380   1.9      joda 				printf("Kerberos V5: "
    381   1.9      joda 				       "krb5_auth_con_getremotesubkey returned NULL key\r\n");
    382   1.1       cgd 			return;
    383   1.1       cgd 		}
    384   1.4   thorpej 		if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
    385   1.4   thorpej 			ret = krb5_mk_rep(telnet_context,
    386   1.7     assar 			    auth_context, &outbuf);
    387   1.4   thorpej 			if (ret) {
    388   1.4   thorpej 				Data(ap, KRB_REJECT,
    389   1.4   thorpej 				    "krb5_mk_rep failed", -1);
    390   1.4   thorpej 				auth_finished(ap, AUTH_REJECT);
    391   1.4   thorpej 				if (auth_debug_mode)
    392   1.4   thorpej 					printf("Kerberos V5: "
    393   1.4   thorpej 					    "krb5_mk_rep failed (%s)\r\n",
    394  1.18     elric 					    get_krb5_err_text(telnet_context,
    395   1.4   thorpej 					    ret));
    396  1.17  christos 				krb5_free_keyblock(telnet_context, key_block);
    397   1.4   thorpej 				return;
    398   1.4   thorpej 			}
    399   1.4   thorpej 			Data(ap, KRB_RESPONSE, outbuf.data, outbuf.length);
    400   1.4   thorpej 		}
    401   1.4   thorpej 		if (krb5_unparse_name(telnet_context, ticket->client, &name))
    402   1.1       cgd 			name = 0;
    403   1.4   thorpej 
    404   1.4   thorpej 		if (UserNameRequested && krb5_kuserok(telnet_context,
    405   1.4   thorpej 		    ticket->client, UserNameRequested)) {
    406  1.16  christos 			Data(ap, KRB_ACCEPT, name ? name : "", name ? -1 : 0);
    407   1.4   thorpej 			if (auth_debug_mode) {
    408   1.4   thorpej 				printf("Kerberos5 identifies him as ``%s''\r\n",
    409   1.4   thorpej 				    name ? name : "");
    410   1.4   thorpej 			}
    411   1.4   thorpej 			if (key_block->keytype == ETYPE_DES_CBC_MD5 ||
    412   1.4   thorpej 			    key_block->keytype == ETYPE_DES_CBC_MD4 ||
    413   1.4   thorpej 			    key_block->keytype == ETYPE_DES_CBC_CRC) {
    414   1.4   thorpej 				Session_Key skey;
    415   1.4   thorpej 
    416   1.4   thorpej 				skey.type = SK_DES;
    417   1.4   thorpej 				skey.length = 8;
    418   1.4   thorpej 				skey.data = key_block->keyvalue.data;
    419   1.4   thorpej 				encrypt_session_key(&skey, 0);
    420   1.4   thorpej 			}
    421   1.4   thorpej 		} else {
    422   1.4   thorpej 			char *msg;
    423   1.4   thorpej 
    424   1.4   thorpej 			asprintf(&msg, "user `%s' is not authorized to "
    425   1.4   thorpej 			    "login as `%s'",
    426   1.4   thorpej 			    name ? name : "<unknown>",
    427   1.4   thorpej 			    UserNameRequested ? UserNameRequested : "<nobody>");
    428   1.4   thorpej 			if (msg == NULL)
    429   1.4   thorpej 				Data(ap, KRB_REJECT, NULL, 0);
    430   1.4   thorpej 			else {
    431   1.4   thorpej 				Data(ap, KRB_REJECT, (void *) msg, -1);
    432   1.4   thorpej 				free(msg);
    433   1.4   thorpej 			}
    434   1.4   thorpej 			auth_finished(ap, AUTH_REJECT);
    435  1.17  christos 			krb5_free_keyblock(telnet_context, key_block);
    436   1.4   thorpej 			break;
    437   1.1       cgd 		}
    438   1.4   thorpej 		auth_finished(ap, AUTH_USER);
    439  1.17  christos 		krb5_free_keyblock(telnet_context, key_block);
    440   1.1       cgd 		break;
    441   1.4   thorpej 	case KRB_FORWARD:{
    442  1.13  christos 			struct passwd pws, *pwd;
    443  1.13  christos 			char pwbuf[1024];
    444   1.4   thorpej 			char ccname[1024];	/* XXX */
    445   1.4   thorpej 			krb5_data inbuf;
    446   1.4   thorpej 			krb5_ccache ccache;
    447   1.4   thorpej 			inbuf.data = (char *) data;
    448   1.4   thorpej 			inbuf.length = cnt;
    449   1.4   thorpej 
    450  1.13  christos 			if (getpwnam_r(UserNameRequested, &pws, pwbuf,
    451  1.14  christos 			    sizeof(pwbuf), &pwd) != 0 || pwd == NULL)
    452   1.4   thorpej 				break;
    453   1.1       cgd 
    454   1.4   thorpej 			snprintf(ccname, sizeof(ccname),
    455   1.4   thorpej 			    "FILE:/tmp/krb5cc_%u", pwd->pw_uid);
    456   1.1       cgd 
    457   1.4   thorpej 			ret = krb5_cc_resolve(telnet_context, ccname, &ccache);
    458   1.4   thorpej 			if (ret) {
    459   1.4   thorpej 				if (auth_debug_mode)
    460   1.4   thorpej 					printf("Kerberos V5: could not get ccache: %s\r\n",
    461  1.18     elric 					    get_krb5_err_text(telnet_context,
    462   1.4   thorpej 					    ret));
    463   1.4   thorpej 				break;
    464   1.4   thorpej 			}
    465   1.4   thorpej 			ret = krb5_cc_initialize(telnet_context, ccache,
    466   1.4   thorpej 			    ticket->client);
    467   1.4   thorpej 			if (ret) {
    468   1.4   thorpej 				if (auth_debug_mode)
    469   1.4   thorpej 					printf("Kerberos V5: could not init ccache: %s\r\n",
    470  1.18     elric 					    get_krb5_err_text(telnet_context,
    471   1.4   thorpej 					        ret));
    472   1.1       cgd 				break;
    473   1.4   thorpej 			}
    474   1.7     assar 			ret = krb5_rd_cred2(telnet_context, auth_context,
    475   1.4   thorpej 			    ccache, &inbuf);
    476   1.4   thorpej 			if (ret) {
    477   1.4   thorpej 				char *errbuf;
    478   1.4   thorpej 
    479   1.4   thorpej 				asprintf(&errbuf,
    480   1.4   thorpej 				    "Read forwarded creds failed: %s",
    481  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    482   1.4   thorpej 				if (errbuf == NULL)
    483   1.4   thorpej 					Data(ap, KRB_FORWARD_REJECT, NULL, 0);
    484   1.4   thorpej 				else
    485   1.4   thorpej 					Data(ap, KRB_FORWARD_REJECT, errbuf, -1);
    486   1.4   thorpej 				if (auth_debug_mode)
    487   1.4   thorpej 					printf("Could not read forwarded credentials: %s\r\n",
    488   1.4   thorpej 					    errbuf);
    489   1.4   thorpej 				free(errbuf);
    490   1.4   thorpej 			} else
    491   1.4   thorpej 				Data(ap, KRB_FORWARD_ACCEPT, 0, 0);
    492   1.4   thorpej 			chown(ccname + 5, pwd->pw_uid, -1);
    493   1.4   thorpej 			if (auth_debug_mode)
    494   1.4   thorpej 				printf("Forwarded credentials obtained\r\n");
    495   1.4   thorpej 			break;
    496   1.1       cgd 		}
    497   1.1       cgd 	default:
    498   1.1       cgd 		if (auth_debug_mode)
    499   1.1       cgd 			printf("Unknown Kerberos option %d\r\n", data[-1]);
    500   1.1       cgd 		Data(ap, KRB_REJECT, 0, 0);
    501   1.1       cgd 		break;
    502   1.1       cgd 	}
    503   1.1       cgd }
    504   1.1       cgd 
    505   1.4   thorpej void
    506   1.4   thorpej kerberos5_reply(Authenticator * ap, unsigned char *data, int cnt)
    507   1.1       cgd {
    508   1.4   thorpej 	static int mutual_complete = 0;
    509   1.1       cgd 
    510   1.1       cgd 	if (cnt-- < 1)
    511   1.1       cgd 		return;
    512   1.1       cgd 	switch (*data++) {
    513   1.1       cgd 	case KRB_REJECT:
    514   1.1       cgd 		if (cnt > 0) {
    515   1.1       cgd 			printf("[ Kerberos V5 refuses authentication because %.*s ]\r\n",
    516   1.4   thorpej 			    cnt, data);
    517   1.1       cgd 		} else
    518   1.1       cgd 			printf("[ Kerberos V5 refuses authentication ]\r\n");
    519   1.1       cgd 		auth_send_retry();
    520   1.1       cgd 		return;
    521   1.4   thorpej 	case KRB_ACCEPT:{
    522   1.4   thorpej 			krb5_error_code ret;
    523   1.4   thorpej 			Session_Key skey;
    524   1.4   thorpej 			krb5_keyblock *keyblock;
    525   1.4   thorpej 
    526   1.4   thorpej 			if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL &&
    527   1.4   thorpej 			    !mutual_complete) {
    528   1.4   thorpej 				printf("[ Kerberos V5 accepted you, but didn't provide mutual authentication! ]\r\n");
    529   1.4   thorpej 				auth_send_retry();
    530   1.4   thorpej 				return;
    531   1.4   thorpej 			}
    532   1.4   thorpej 			if (cnt)
    533   1.4   thorpej 				printf("[ Kerberos V5 accepts you as ``%.*s'' ]\r\n", cnt, data);
    534   1.4   thorpej 			else
    535   1.4   thorpej 				printf("[ Kerberos V5 accepts you ]\r\n");
    536   1.4   thorpej 
    537   1.4   thorpej 			ret = krb5_auth_con_getlocalsubkey(telnet_context,
    538   1.4   thorpej 			    auth_context, &keyblock);
    539   1.4   thorpej 			if (ret)
    540   1.4   thorpej 				ret = krb5_auth_con_getkey(telnet_context,
    541   1.4   thorpej 				    auth_context, &keyblock);
    542   1.4   thorpej 			if (ret) {
    543   1.4   thorpej 				printf("[ krb5_auth_con_getkey: %s ]\r\n",
    544  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    545   1.4   thorpej 				auth_send_retry();
    546   1.4   thorpej 				return;
    547   1.4   thorpej 			}
    548   1.1       cgd 			skey.type = SK_DES;
    549   1.1       cgd 			skey.length = 8;
    550   1.4   thorpej 			skey.data = keyblock->keyvalue.data;
    551   1.1       cgd 			encrypt_session_key(&skey, 0);
    552  1.15  christos 			krb5_free_keyblock(telnet_context, keyblock);
    553   1.4   thorpej 			auth_finished(ap, AUTH_USER);
    554   1.4   thorpej 			if (forward_flags & OPTS_FORWARD_CREDS)
    555   1.4   thorpej 				kerberos5_forward(ap);
    556   1.4   thorpej 			break;
    557   1.1       cgd 		}
    558   1.1       cgd 	case KRB_RESPONSE:
    559   1.4   thorpej 		if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
    560   1.4   thorpej 			/* the rest of the reply should contain a krb_ap_rep */
    561   1.4   thorpej 			krb5_ap_rep_enc_part *reply;
    562   1.4   thorpej 			krb5_data inbuf;
    563   1.4   thorpej 			krb5_error_code ret;
    564   1.4   thorpej 
    565   1.4   thorpej 			inbuf.length = cnt;
    566   1.4   thorpej 			inbuf.data = (char *) data;
    567   1.4   thorpej 
    568   1.4   thorpej 			ret = krb5_rd_rep(telnet_context,
    569   1.4   thorpej 			    auth_context, &inbuf, &reply);
    570   1.4   thorpej 			if (ret) {
    571   1.4   thorpej 				printf("[ Mutual authentication failed: %s ]\r\n",
    572  1.18     elric 				    get_krb5_err_text(telnet_context, ret));
    573   1.4   thorpej 				auth_send_retry();
    574   1.4   thorpej 				return;
    575   1.4   thorpej 			}
    576   1.4   thorpej 			krb5_free_ap_rep_enc_part(telnet_context, reply);
    577   1.4   thorpej 			mutual_complete = 1;
    578   1.1       cgd 		}
    579   1.4   thorpej 		return;
    580   1.4   thorpej 	case KRB_FORWARD_ACCEPT:
    581   1.4   thorpej 		printf("[ Kerberos V5 accepted forwarded credentials ]\r\n");
    582   1.4   thorpej 		return;
    583   1.4   thorpej 	case KRB_FORWARD_REJECT:
    584   1.4   thorpej 		printf("[ Kerberos V5 refuses forwarded credentials because %.*s ]\r\n",
    585   1.4   thorpej 		    cnt, data);
    586   1.4   thorpej 		return;
    587   1.1       cgd 	default:
    588   1.1       cgd 		if (auth_debug_mode)
    589   1.1       cgd 			printf("Unknown Kerberos option %d\r\n", data[-1]);
    590   1.1       cgd 		return;
    591   1.1       cgd 	}
    592   1.1       cgd }
    593   1.1       cgd 
    594   1.4   thorpej int
    595  1.11    itojun kerberos5_status(Authenticator *ap, char *name, size_t l, int level)
    596   1.1       cgd {
    597   1.1       cgd 	if (level < AUTH_USER)
    598   1.4   thorpej 		return (level);
    599   1.1       cgd 
    600   1.1       cgd 	if (UserNameRequested &&
    601   1.4   thorpej 	    krb5_kuserok(telnet_context, ticket->client, UserNameRequested)) {
    602  1.11    itojun 		strlcpy(name, UserNameRequested, l);
    603   1.4   thorpej 		return (AUTH_VALID);
    604   1.1       cgd 	} else
    605   1.4   thorpej 		return (AUTH_USER);
    606   1.1       cgd }
    607   1.1       cgd #define	BUMP(buf, len)		while (*(buf)) {++(buf), --(len);}
    608   1.4   thorpej #define	ADDC(buf, len, c)	if ((len) > 0) {*(buf)++ = (c); --(len);}
    609   1.1       cgd 
    610   1.4   thorpej void
    611   1.4   thorpej kerberos5_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen)
    612   1.1       cgd {
    613   1.4   thorpej 	int i;
    614   1.1       cgd 
    615   1.4   thorpej 	buf[buflen - 1] = '\0';	/* make sure its NULL terminated */
    616   1.1       cgd 	buflen -= 1;
    617   1.1       cgd 
    618   1.4   thorpej 	switch (data[3]) {
    619   1.4   thorpej 	case KRB_REJECT:	/* Rejected (reason might follow) */
    620   1.4   thorpej 		strlcpy((char *) buf, " REJECT ", buflen);
    621   1.1       cgd 		goto common;
    622   1.1       cgd 
    623   1.4   thorpej 	case KRB_ACCEPT:	/* Accepted (name might follow) */
    624   1.4   thorpej 		strlcpy((char *) buf, " ACCEPT ", buflen);
    625   1.4   thorpej common:
    626   1.1       cgd 		BUMP(buf, buflen);
    627   1.1       cgd 		if (cnt <= 4)
    628   1.1       cgd 			break;
    629   1.1       cgd 		ADDC(buf, buflen, '"');
    630   1.1       cgd 		for (i = 4; i < cnt; i++)
    631   1.1       cgd 			ADDC(buf, buflen, data[i]);
    632   1.1       cgd 		ADDC(buf, buflen, '"');
    633   1.1       cgd 		ADDC(buf, buflen, '\0');
    634   1.1       cgd 		break;
    635   1.1       cgd 
    636   1.4   thorpej 
    637   1.4   thorpej 	case KRB_AUTH:		/* Authentication data follows */
    638   1.4   thorpej 		strlcpy((char *) buf, " AUTH", buflen);
    639   1.4   thorpej 		goto common2;
    640   1.4   thorpej 
    641   1.4   thorpej 	case KRB_RESPONSE:
    642   1.4   thorpej 		strlcpy((char *) buf, " RESPONSE", buflen);
    643   1.1       cgd 		goto common2;
    644   1.1       cgd 
    645   1.4   thorpej 	case KRB_FORWARD:	/* Forwarded credentials follow */
    646   1.4   thorpej 		strlcpy((char *) buf, " FORWARD", buflen);
    647   1.1       cgd 		goto common2;
    648   1.1       cgd 
    649   1.4   thorpej 	case KRB_FORWARD_ACCEPT:	/* Forwarded credentials accepted */
    650   1.4   thorpej 		strlcpy((char *) buf, " FORWARD_ACCEPT", buflen);
    651   1.4   thorpej 		goto common2;
    652   1.4   thorpej 
    653   1.4   thorpej 	case KRB_FORWARD_REJECT:	/* Forwarded credentials rejected */
    654   1.4   thorpej 		/* (reason might follow) */
    655   1.4   thorpej 		strlcpy((char *) buf, " FORWARD_REJECT", buflen);
    656   1.1       cgd 		goto common2;
    657   1.1       cgd 
    658   1.1       cgd 	default:
    659   1.4   thorpej 		snprintf(buf, buflen, " %d (unknown)", data[3]);
    660   1.4   thorpej common2:
    661   1.1       cgd 		BUMP(buf, buflen);
    662   1.1       cgd 		for (i = 4; i < cnt; i++) {
    663   1.4   thorpej 			snprintf(buf, buflen, " %d", data[i]);
    664   1.1       cgd 			BUMP(buf, buflen);
    665   1.1       cgd 		}
    666   1.1       cgd 		break;
    667   1.1       cgd 	}
    668   1.1       cgd }
    669   1.4   thorpej 
    670   1.4   thorpej void
    671   1.4   thorpej kerberos5_forward(Authenticator * ap)
    672   1.4   thorpej {
    673   1.4   thorpej 	krb5_error_code ret;
    674   1.4   thorpej 	krb5_ccache ccache;
    675   1.4   thorpej 	krb5_creds creds;
    676   1.4   thorpej 	krb5_kdc_flags flags;
    677   1.4   thorpej 	krb5_data out_data;
    678   1.4   thorpej 	krb5_principal principal;
    679   1.4   thorpej 
    680   1.4   thorpej 	ret = krb5_cc_default(telnet_context, &ccache);
    681   1.4   thorpej 	if (ret) {
    682   1.4   thorpej 		if (auth_debug_mode)
    683   1.4   thorpej 			printf("KerberosV5: could not get default ccache: %s\r\n",
    684  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    685   1.4   thorpej 		return;
    686   1.4   thorpej 	}
    687   1.4   thorpej 	ret = krb5_cc_get_principal(telnet_context, ccache, &principal);
    688   1.4   thorpej 	if (ret) {
    689   1.4   thorpej 		if (auth_debug_mode)
    690   1.4   thorpej 			printf("KerberosV5: could not get principal: %s\r\n",
    691  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    692   1.4   thorpej 		return;
    693   1.4   thorpej 	}
    694   1.4   thorpej 	memset(&creds, 0, sizeof(creds));
    695   1.4   thorpej 
    696   1.4   thorpej 	creds.client = principal;
    697   1.4   thorpej 
    698   1.4   thorpej 	ret = krb5_build_principal(telnet_context, &creds.server,
    699   1.4   thorpej 	    strlen(principal->realm), principal->realm, "krbtgt",
    700   1.4   thorpej 	    principal->realm, NULL);
    701   1.4   thorpej 
    702   1.4   thorpej 	if (ret) {
    703   1.4   thorpej 		if (auth_debug_mode)
    704   1.4   thorpej 			printf("KerberosV5: could not get principal: %s\r\n",
    705  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    706   1.4   thorpej 		return;
    707   1.4   thorpej 	}
    708   1.4   thorpej 	creds.times.endtime = 0;
    709   1.4   thorpej 
    710   1.4   thorpej 	flags.i = 0;
    711   1.4   thorpej 	flags.b.forwarded = 1;
    712   1.4   thorpej 	if (forward_flags & OPTS_FORWARDABLE_CREDS)
    713   1.4   thorpej 		flags.b.forwardable = 1;
    714   1.4   thorpej 
    715   1.4   thorpej 	ret = krb5_get_forwarded_creds(telnet_context, auth_context,
    716   1.4   thorpej 	    ccache, flags.i, RemoteHostName, &creds, &out_data);
    717   1.4   thorpej 	if (ret) {
    718   1.4   thorpej 		if (auth_debug_mode)
    719   1.4   thorpej 			printf("Kerberos V5: error getting forwarded creds: %s\r\n",
    720  1.18     elric 			    get_krb5_err_text(telnet_context, ret));
    721   1.4   thorpej 		return;
    722   1.4   thorpej 	}
    723   1.4   thorpej 	if (!Data(ap, KRB_FORWARD, out_data.data, out_data.length)) {
    724   1.4   thorpej 		if (auth_debug_mode)
    725   1.4   thorpej 			printf("Not enough room for authentication data\r\n");
    726   1.4   thorpej 	} else {
    727   1.4   thorpej 		if (auth_debug_mode)
    728   1.4   thorpej 			printf("Forwarded local Kerberos V5 credentials to server\r\n");
    729   1.4   thorpej 	}
    730   1.4   thorpej }
    731   1.4   thorpej #endif /* KRB5 */
    732