2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * $FreeBSD: src/crypto/telnet/libtelnet/kerberos5.c,v 1.1.1.1.8.2 2003/04/24 19:13:59 nectar Exp $
37 * Copyright (C) 1990 by the Massachusetts Institute of Technology
39 * Export of this software from the United States of America may
40 * require a specific license from the United States Government.
41 * It is the responsibility of any person or organization contemplating
42 * export to obtain such a license before exporting.
44 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
45 * distribute this software and its documentation for any purpose and
46 * without fee is hereby granted, provided that the above copyright
47 * notice appear in all copies and that both that copyright notice and
48 * this permission notice appear in supporting documentation, and that
49 * the name of M.I.T. not be used in advertising or publicity pertaining
50 * to distribution of the software without specific, written prior
51 * permission. M.I.T. makes no representations about the suitability of
52 * this software for any purpose. It is provided "as is" without express
53 * or implied warranty.
58 #include <arpa/telnet.h>
66 #define Authenticator k5_Authenticator
74 int forward_flags = 0; /* Flags get set in telnet/main.c on -f and -F */
76 /* These values need to be the same as those defined in telnet/main.c. */
77 /* Either define them in both places, or put in some common header file. */
78 #define OPTS_FORWARD_CREDS 0x00000002
79 #define OPTS_FORWARDABLE_CREDS 0x00000001
81 void kerberos5_forward (Authenticator *);
83 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0,
84 AUTHTYPE_KERBEROS_V5, };
86 #define KRB_AUTH 0 /* Authentication data follows */
87 #define KRB_REJECT 1 /* Rejected (reason might follow) */
88 #define KRB_ACCEPT 2 /* Accepted */
89 #define KRB_RESPONSE 3 /* Response for mutual auth. */
91 #define KRB_FORWARD 4 /* Forwarded credentials follow */
92 #define KRB_FORWARD_ACCEPT 5 /* Forwarded credentials accepted */
93 #define KRB_FORWARD_REJECT 6 /* Forwarded credentials rejected */
95 static krb5_data auth;
96 static krb5_ticket *ticket;
98 static krb5_context context;
99 static krb5_auth_context auth_context;
102 Data(Authenticator *ap, int type, const char *d, int c)
104 unsigned char *p = str_data + 4;
105 const unsigned char *cd = d;
110 if (auth_debug_mode) {
111 printf("%s:%d: [%d] (%d)",
112 str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY",
122 if ((*p++ = *cd++) == IAC)
127 if (str_data[3] == TELQUAL_IS)
128 printsub('>', &str_data[2], p - &str_data[2]);
129 return(net_write(str_data, p - str_data));
133 kerberos5_init(Authenticator *ap __unused, int server)
137 ret = krb5_init_context(&context);
142 krb5_kt_cursor cursor;
144 ret = krb5_kt_default(context, &kt);
148 ret = krb5_kt_start_seq_get (context, kt, &cursor);
150 krb5_kt_close (context, kt);
153 krb5_kt_end_seq_get (context, kt, &cursor);
154 krb5_kt_close (context, kt);
156 str_data[3] = TELQUAL_REPLY;
158 str_data[3] = TELQUAL_IS;
165 kerberos5_send(const char *name, Authenticator *ap)
170 krb5_data cksum_data;
173 if (!UserNameRequested) {
174 if (auth_debug_mode) {
175 printf("Kerberos V5: no user name supplied\r\n");
180 ret = krb5_cc_default(context, &ccache);
182 if (auth_debug_mode) {
183 printf("Kerberos V5: could not get default ccache: %s\r\n",
184 krb5_get_err_text (context, ret));
189 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL)
190 ap_opts = AP_OPTS_MUTUAL_REQUIRED;
193 ap_opts |= AP_OPTS_USE_SUBKEY;
195 ret = krb5_auth_con_init (context, &auth_context);
197 if (auth_debug_mode) {
198 printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
199 krb5_get_err_text(context, ret));
204 ret = krb5_auth_con_setaddrs_from_fd (context,
208 if (auth_debug_mode) {
209 printf ("Kerberos V5:"
210 " krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
211 krb5_get_err_text(context, ret));
216 krb5_auth_con_setkeytype (context, auth_context, KEYTYPE_DES);
221 cksum_data.length = sizeof(foo);
222 cksum_data.data = foo;
226 krb5_principal service;
230 ret = krb5_sname_to_principal (context,
236 if (auth_debug_mode) {
237 printf ("Kerberos V5:"
238 " krb5_sname_to_principal(%s) failed (%s)\r\n",
239 RemoteHostName, krb5_get_err_text(context, ret));
243 ret = krb5_unparse_name_fixed(context, service, sname, sizeof(sname));
245 if (auth_debug_mode) {
246 printf ("Kerberos V5:"
247 " krb5_unparse_name_fixed failed (%s)\r\n",
248 krb5_get_err_text(context, ret));
252 printf("[ Trying %s (%s)... ]\r\n", name, sname);
253 ret = krb5_mk_req_exact(context, &auth_context, ap_opts,
255 &cksum_data, ccache, &auth);
256 krb5_free_principal (context, service);
260 if (1 || auth_debug_mode) {
261 printf("Kerberos V5: mk_req failed (%s)\r\n",
262 krb5_get_err_text(context, ret));
267 if (!auth_sendname((unsigned char *)UserNameRequested,
268 strlen(UserNameRequested))) {
270 printf("Not enough room for user name\r\n");
273 if (!Data(ap, KRB_AUTH, auth.data, auth.length)) {
275 printf("Not enough room for authentication data\r\n");
278 if (auth_debug_mode) {
279 printf("Sent Kerberos V5 credentials to server\r\n");
285 kerberos5_send_mutual(Authenticator *ap)
287 return kerberos5_send("mutual KERBEROS5", ap);
291 kerberos5_send_oneway(Authenticator *ap)
293 return kerberos5_send("KERBEROS5", ap);
297 kerberos5_is(Authenticator *ap, unsigned char *data, int cnt)
301 krb5_keyblock *key_block;
303 krb5_principal server;
310 auth.data = (char *)data;
315 ret = krb5_auth_con_init (context, &auth_context);
317 Data(ap, KRB_REJECT, "krb5_auth_con_init failed", -1);
318 auth_finished(ap, AUTH_REJECT);
320 printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
321 krb5_get_err_text(context, ret));
325 ret = krb5_auth_con_setaddrs_from_fd (context,
329 Data(ap, KRB_REJECT, "krb5_auth_con_setaddrs_from_fd failed", -1);
330 auth_finished(ap, AUTH_REJECT);
332 printf("Kerberos V5: "
333 "krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
334 krb5_get_err_text(context, ret));
338 ret = krb5_sock_to_principal (context,
344 Data(ap, KRB_REJECT, "krb5_sock_to_principal failed", -1);
345 auth_finished(ap, AUTH_REJECT);
347 printf("Kerberos V5: "
348 "krb5_sock_to_principal failed (%s)\r\n",
349 krb5_get_err_text(context, ret));
353 ret = krb5_rd_req(context,
361 krb5_free_principal (context, server);
366 "Read req failed: %s",
367 krb5_get_err_text(context, ret));
368 Data(ap, KRB_REJECT, errbuf, -1);
370 printf("%s\r\n", errbuf);
381 ret = krb5_verify_authenticator_checksum(context,
388 asprintf(&errbuf, "Bad checksum: %s",
389 krb5_get_err_text(context, ret));
390 Data(ap, KRB_REJECT, errbuf, -1);
392 printf ("%s\r\n", errbuf);
397 ret = krb5_auth_con_getremotesubkey (context,
402 Data(ap, KRB_REJECT, "krb5_auth_con_getremotesubkey failed", -1);
403 auth_finished(ap, AUTH_REJECT);
405 printf("Kerberos V5: "
406 "krb5_auth_con_getremotesubkey failed (%s)\r\n",
407 krb5_get_err_text(context, ret));
411 if (key_block == NULL) {
412 ret = krb5_auth_con_getkey(context,
417 Data(ap, KRB_REJECT, "krb5_auth_con_getkey failed", -1);
418 auth_finished(ap, AUTH_REJECT);
420 printf("Kerberos V5: "
421 "krb5_auth_con_getkey failed (%s)\r\n",
422 krb5_get_err_text(context, ret));
425 if (key_block == NULL) {
426 Data(ap, KRB_REJECT, "no subkey received", -1);
427 auth_finished(ap, AUTH_REJECT);
429 printf("Kerberos V5: "
430 "krb5_auth_con_getremotesubkey returned NULL key\r\n");
434 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
435 ret = krb5_mk_rep(context, auth_context, &outbuf);
438 "krb5_mk_rep failed", -1);
439 auth_finished(ap, AUTH_REJECT);
441 printf("Kerberos V5: "
442 "krb5_mk_rep failed (%s)\r\n",
443 krb5_get_err_text(context, ret));
446 Data(ap, KRB_RESPONSE, outbuf.data, outbuf.length);
448 if (krb5_unparse_name(context, ticket->client, &name))
451 if(UserNameRequested && krb5_kuserok(context,
453 UserNameRequested)) {
454 Data(ap, KRB_ACCEPT, name, name ? -1 : 0);
455 if (auth_debug_mode) {
456 printf("Kerberos5 identifies him as ``%s''\r\n",
460 if(key_block->keytype == ETYPE_DES_CBC_MD5 ||
461 key_block->keytype == ETYPE_DES_CBC_MD4 ||
462 key_block->keytype == ETYPE_DES_CBC_CRC) {
467 skey.data = key_block->keyvalue.data;
468 encrypt_session_key(&skey, 0);
474 asprintf (&msg, "user `%s' is not authorized to "
476 name ? name : "<unknown>",
477 UserNameRequested ? UserNameRequested : "<nobody>");
479 Data(ap, KRB_REJECT, NULL, 0);
481 Data(ap, KRB_REJECT, (void *)msg, -1);
484 auth_finished (ap, AUTH_REJECT);
485 krb5_free_keyblock_contents(context, key_block);
488 auth_finished(ap, AUTH_USER);
489 krb5_free_keyblock_contents(context, key_block);
494 char ccname[1024]; /* XXX */
497 inbuf.data = (char *)data;
500 pwd = getpwnam (UserNameRequested);
504 snprintf (ccname, sizeof(ccname),
505 "FILE:/tmp/krb5cc_%u", pwd->pw_uid);
507 ret = krb5_cc_resolve (context, ccname, &ccache);
510 printf ("Kerberos V5: could not get ccache: %s\r\n",
511 krb5_get_err_text(context, ret));
515 ret = krb5_cc_initialize (context,
520 printf ("Kerberos V5: could not init ccache: %s\r\n",
521 krb5_get_err_text(context, ret));
526 esetenv("KRB5CCNAME", ccname, 1);
528 ret = krb5_rd_cred2 (context,
536 "Read forwarded creds failed: %s",
537 krb5_get_err_text (context, ret));
539 Data(ap, KRB_FORWARD_REJECT, NULL, 0);
541 Data(ap, KRB_FORWARD_REJECT, errbuf, -1);
543 printf("Could not read forwarded credentials: %s\r\n",
547 Data(ap, KRB_FORWARD_ACCEPT, 0, 0);
552 chown (ccname + 5, pwd->pw_uid, -1);
554 printf("Forwarded credentials obtained\r\n");
559 printf("Unknown Kerberos option %d\r\n", data[-1]);
560 Data(ap, KRB_REJECT, 0, 0);
566 kerberos5_reply(Authenticator *ap, unsigned char *data, int cnt)
568 static int mutual_complete = 0;
575 printf("[ Kerberos V5 refuses authentication because %.*s ]\r\n",
578 printf("[ Kerberos V5 refuses authentication ]\r\n");
584 krb5_keyblock *keyblock;
586 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL &&
588 printf("[ Kerberos V5 accepted you, but didn't provide mutual authentication! ]\r\n");
593 printf("[ Kerberos V5 accepts you as ``%.*s'' ]\r\n", cnt, data);
595 printf("[ Kerberos V5 accepts you ]\r\n");
597 ret = krb5_auth_con_getlocalsubkey (context,
601 ret = krb5_auth_con_getkey (context,
605 printf("[ krb5_auth_con_getkey: %s ]\r\n",
606 krb5_get_err_text(context, ret));
613 skey.data = keyblock->keyvalue.data;
614 encrypt_session_key(&skey, 0);
615 krb5_free_keyblock_contents (context, keyblock);
616 auth_finished(ap, AUTH_USER);
617 if (forward_flags & OPTS_FORWARD_CREDS)
618 kerberos5_forward(ap);
622 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
623 /* the rest of the reply should contain a krb_ap_rep */
624 krb5_ap_rep_enc_part *reply;
629 inbuf.data = (char *)data;
631 ret = krb5_rd_rep(context, auth_context, &inbuf, &reply);
633 printf("[ Mutual authentication failed: %s ]\r\n",
634 krb5_get_err_text (context, ret));
638 krb5_free_ap_rep_enc_part(context, reply);
642 case KRB_FORWARD_ACCEPT:
643 printf("[ Kerberos V5 accepted forwarded credentials ]\r\n");
645 case KRB_FORWARD_REJECT:
646 printf("[ Kerberos V5 refuses forwarded credentials because %.*s ]\r\n",
651 printf("Unknown Kerberos option %d\r\n", data[-1]);
657 kerberos5_status(Authenticator *ap __unused, char *name, int level)
659 if (level < AUTH_USER)
662 if (UserNameRequested &&
663 krb5_kuserok(context,
667 strcpy(name, UserNameRequested);
673 #define BUMP(buf, len) while (*(buf)) {++(buf), --(len);}
674 #define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);}
677 kerberos5_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen)
681 buf[buflen-1] = '\0'; /* make sure its NULL terminated */
685 case KRB_REJECT: /* Rejected (reason might follow) */
686 strlcpy((char *)buf, " REJECT ", buflen);
689 case KRB_ACCEPT: /* Accepted (name might follow) */
690 strlcpy((char *)buf, " ACCEPT ", buflen);
695 ADDC(buf, buflen, '"');
696 for (i = 4; i < cnt; i++)
697 ADDC(buf, buflen, data[i]);
698 ADDC(buf, buflen, '"');
699 ADDC(buf, buflen, '\0');
703 case KRB_AUTH: /* Authentication data follows */
704 strlcpy((char *)buf, " AUTH", buflen);
708 strlcpy((char *)buf, " RESPONSE", buflen);
711 case KRB_FORWARD: /* Forwarded credentials follow */
712 strlcpy((char *)buf, " FORWARD", buflen);
715 case KRB_FORWARD_ACCEPT: /* Forwarded credentials accepted */
716 strlcpy((char *)buf, " FORWARD_ACCEPT", buflen);
719 case KRB_FORWARD_REJECT: /* Forwarded credentials rejected */
720 /* (reason might follow) */
721 strlcpy((char *)buf, " FORWARD_REJECT", buflen);
725 snprintf(buf, buflen, " %d (unknown)", data[3]);
728 for (i = 4; i < cnt; i++) {
729 snprintf(buf, buflen, " %d", data[i]);
737 kerberos5_forward(Authenticator *ap)
742 krb5_kdc_flags flags;
744 krb5_principal principal;
746 ret = krb5_cc_default (context, &ccache);
749 printf ("KerberosV5: could not get default ccache: %s\r\n",
750 krb5_get_err_text (context, ret));
754 ret = krb5_cc_get_principal (context, ccache, &principal);
757 printf ("KerberosV5: could not get principal: %s\r\n",
758 krb5_get_err_text (context, ret));
762 memset (&creds, 0, sizeof(creds));
764 creds.client = principal;
766 ret = krb5_build_principal (context,
768 strlen(principal->realm),
776 printf ("KerberosV5: could not get principal: %s\r\n",
777 krb5_get_err_text (context, ret));
781 creds.times.endtime = 0;
784 flags.b.forwarded = 1;
785 if (forward_flags & OPTS_FORWARDABLE_CREDS)
786 flags.b.forwardable = 1;
788 ret = krb5_get_forwarded_creds (context,
797 printf ("Kerberos V5: error getting forwarded creds: %s\r\n",
798 krb5_get_err_text (context, ret));
802 if(!Data(ap, KRB_FORWARD, out_data.data, out_data.length)) {
804 printf("Not enough room for authentication data\r\n");
807 printf("Forwarded local Kerberos V5 credentials to server\r\n");
812 /* if this was a K5 authentication try and join a PAG for the user. */
814 kerberos5_dfspag(void)
817 dfspag = krb5_dfs_pag(context, dfsfwd, ticket->client,