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
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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
35 * Copyright (C) 1990 by the Massachusetts Institute of Technology
37 * Export of this software from the United States of America may
38 * require a specific license from the United States Government.
39 * It is the responsibility of any person or organization contemplating
40 * export to obtain such a license before exporting.
42 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
43 * distribute this software and its documentation for any purpose and
44 * without fee is hereby granted, provided that the above copyright
45 * notice appear in all copies and that both that copyright notice and
46 * this permission notice appear in supporting documentation, and that
47 * the name of M.I.T. not be used in advertising or publicity pertaining
48 * to distribution of the software without specific, written prior
49 * permission. M.I.T. makes no representations about the suitability of
50 * this software for any purpose. It is provided "as is" without express
51 * or implied warranty.
54 #include <sys/cdefs.h>
56 __FBSDID("$FreeBSD$");
60 #include <arpa/telnet.h>
68 #define Authenticator k5_Authenticator
76 int forward_flags = 0; /* Flags get set in telnet/main.c on -f and -F */
78 /* These values need to be the same as those defined in telnet/main.c. */
79 /* Either define them in both places, or put in some common header file. */
80 #define OPTS_FORWARD_CREDS 0x00000002
81 #define OPTS_FORWARDABLE_CREDS 0x00000001
83 void kerberos5_forward (Authenticator *);
85 static unsigned char str_data[1024] = { IAC, SB, TELOPT_AUTHENTICATION, 0,
86 AUTHTYPE_KERBEROS_V5, };
88 #define KRB_AUTH 0 /* Authentication data follows */
89 #define KRB_REJECT 1 /* Rejected (reason might follow) */
90 #define KRB_ACCEPT 2 /* Accepted */
91 #define KRB_RESPONSE 3 /* Response for mutual auth. */
93 #define KRB_FORWARD 4 /* Forwarded credentials follow */
94 #define KRB_FORWARD_ACCEPT 5 /* Forwarded credentials accepted */
95 #define KRB_FORWARD_REJECT 6 /* Forwarded credentials rejected */
97 static krb5_data auth;
98 static krb5_ticket *ticket;
100 static krb5_context context;
101 static krb5_auth_context auth_context;
104 Data(Authenticator *ap, int type, const char *d, int c)
106 unsigned char *p = str_data + 4;
107 const unsigned char *cd = d;
112 if (auth_debug_mode) {
113 printf("%s:%d: [%d] (%d)",
114 str_data[3] == TELQUAL_IS ? ">>>IS" : ">>>REPLY",
124 if ((*p++ = *cd++) == IAC)
129 if (str_data[3] == TELQUAL_IS)
130 printsub('>', &str_data[2], p - &str_data[2]);
131 return(net_write(str_data, p - str_data));
135 kerberos5_init(Authenticator *ap __unused, int server)
139 ret = krb5_init_context(&context);
144 krb5_kt_cursor cursor;
146 ret = krb5_kt_default(context, &kt);
150 ret = krb5_kt_start_seq_get (context, kt, &cursor);
152 krb5_kt_close (context, kt);
155 krb5_kt_end_seq_get (context, kt, &cursor);
156 krb5_kt_close (context, kt);
158 str_data[3] = TELQUAL_REPLY;
160 str_data[3] = TELQUAL_IS;
167 kerberos5_send(const char *name, Authenticator *ap)
172 krb5_data cksum_data;
175 if (!UserNameRequested) {
176 if (auth_debug_mode) {
177 printf("Kerberos V5: no user name supplied\r\n");
182 ret = krb5_cc_default(context, &ccache);
184 if (auth_debug_mode) {
185 printf("Kerberos V5: could not get default ccache: %s\r\n",
186 krb5_get_err_text (context, ret));
191 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL)
192 ap_opts = AP_OPTS_MUTUAL_REQUIRED;
195 ap_opts |= AP_OPTS_USE_SUBKEY;
197 ret = krb5_auth_con_init (context, &auth_context);
199 if (auth_debug_mode) {
200 printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
201 krb5_get_err_text(context, ret));
206 ret = krb5_auth_con_setaddrs_from_fd (context,
210 if (auth_debug_mode) {
211 printf ("Kerberos V5:"
212 " krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
213 krb5_get_err_text(context, ret));
218 krb5_auth_con_setkeytype (context, auth_context, KEYTYPE_DES);
223 cksum_data.length = sizeof(foo);
224 cksum_data.data = foo;
228 krb5_principal service;
232 ret = krb5_sname_to_principal (context,
238 if (auth_debug_mode) {
239 printf ("Kerberos V5:"
240 " krb5_sname_to_principal(%s) failed (%s)\r\n",
241 RemoteHostName, krb5_get_err_text(context, ret));
245 ret = krb5_unparse_name_fixed(context, service, sname, sizeof(sname));
247 if (auth_debug_mode) {
248 printf ("Kerberos V5:"
249 " krb5_unparse_name_fixed failed (%s)\r\n",
250 krb5_get_err_text(context, ret));
254 printf("[ Trying %s (%s)... ]\r\n", name, sname);
255 ret = krb5_mk_req_exact(context, &auth_context, ap_opts,
257 &cksum_data, ccache, &auth);
258 krb5_free_principal (context, service);
262 if (1 || auth_debug_mode) {
263 printf("Kerberos V5: mk_req failed (%s)\r\n",
264 krb5_get_err_text(context, ret));
269 if (!auth_sendname((unsigned char *)UserNameRequested,
270 strlen(UserNameRequested))) {
272 printf("Not enough room for user name\r\n");
275 if (!Data(ap, KRB_AUTH, auth.data, auth.length)) {
277 printf("Not enough room for authentication data\r\n");
280 if (auth_debug_mode) {
281 printf("Sent Kerberos V5 credentials to server\r\n");
287 kerberos5_send_mutual(Authenticator *ap)
289 return kerberos5_send("mutual KERBEROS5", ap);
293 kerberos5_send_oneway(Authenticator *ap)
295 return kerberos5_send("KERBEROS5", ap);
299 kerberos5_is(Authenticator *ap, unsigned char *data, int cnt)
303 krb5_keyblock *key_block;
305 krb5_principal server;
312 auth.data = (char *)data;
317 ret = krb5_auth_con_init (context, &auth_context);
319 Data(ap, KRB_REJECT, "krb5_auth_con_init failed", -1);
320 auth_finished(ap, AUTH_REJECT);
322 printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
323 krb5_get_err_text(context, ret));
327 ret = krb5_auth_con_setaddrs_from_fd (context,
331 Data(ap, KRB_REJECT, "krb5_auth_con_setaddrs_from_fd failed", -1);
332 auth_finished(ap, AUTH_REJECT);
334 printf("Kerberos V5: "
335 "krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
336 krb5_get_err_text(context, ret));
340 ret = krb5_sock_to_principal (context,
346 Data(ap, KRB_REJECT, "krb5_sock_to_principal failed", -1);
347 auth_finished(ap, AUTH_REJECT);
349 printf("Kerberos V5: "
350 "krb5_sock_to_principal failed (%s)\r\n",
351 krb5_get_err_text(context, ret));
355 ret = krb5_rd_req(context,
363 krb5_free_principal (context, server);
368 "Read req failed: %s",
369 krb5_get_err_text(context, ret));
370 Data(ap, KRB_REJECT, errbuf, -1);
372 printf("%s\r\n", errbuf);
383 ret = krb5_verify_authenticator_checksum(context,
390 asprintf(&errbuf, "Bad checksum: %s",
391 krb5_get_err_text(context, ret));
392 Data(ap, KRB_REJECT, errbuf, -1);
394 printf ("%s\r\n", errbuf);
399 ret = krb5_auth_con_getremotesubkey (context,
404 Data(ap, KRB_REJECT, "krb5_auth_con_getremotesubkey failed", -1);
405 auth_finished(ap, AUTH_REJECT);
407 printf("Kerberos V5: "
408 "krb5_auth_con_getremotesubkey failed (%s)\r\n",
409 krb5_get_err_text(context, ret));
413 if (key_block == NULL) {
414 ret = krb5_auth_con_getkey(context,
419 Data(ap, KRB_REJECT, "krb5_auth_con_getkey failed", -1);
420 auth_finished(ap, AUTH_REJECT);
422 printf("Kerberos V5: "
423 "krb5_auth_con_getkey failed (%s)\r\n",
424 krb5_get_err_text(context, ret));
427 if (key_block == NULL) {
428 Data(ap, KRB_REJECT, "no subkey received", -1);
429 auth_finished(ap, AUTH_REJECT);
431 printf("Kerberos V5: "
432 "krb5_auth_con_getremotesubkey returned NULL key\r\n");
436 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
437 ret = krb5_mk_rep(context, auth_context, &outbuf);
440 "krb5_mk_rep failed", -1);
441 auth_finished(ap, AUTH_REJECT);
443 printf("Kerberos V5: "
444 "krb5_mk_rep failed (%s)\r\n",
445 krb5_get_err_text(context, ret));
448 Data(ap, KRB_RESPONSE, outbuf.data, outbuf.length);
450 if (krb5_unparse_name(context, ticket->client, &name))
453 if(UserNameRequested && krb5_kuserok(context,
455 UserNameRequested)) {
456 Data(ap, KRB_ACCEPT, name, name ? -1 : 0);
457 if (auth_debug_mode) {
458 printf("Kerberos5 identifies him as ``%s''\r\n",
462 if(key_block->keytype == ETYPE_DES_CBC_MD5 ||
463 key_block->keytype == ETYPE_DES_CBC_MD4 ||
464 key_block->keytype == ETYPE_DES_CBC_CRC) {
469 skey.data = key_block->keyvalue.data;
470 encrypt_session_key(&skey, 0);
476 asprintf (&msg, "user `%s' is not authorized to "
478 name ? name : "<unknown>",
479 UserNameRequested ? UserNameRequested : "<nobody>");
481 Data(ap, KRB_REJECT, NULL, 0);
483 Data(ap, KRB_REJECT, (void *)msg, -1);
486 auth_finished (ap, AUTH_REJECT);
487 krb5_free_keyblock_contents(context, key_block);
490 auth_finished(ap, AUTH_USER);
491 krb5_free_keyblock_contents(context, key_block);
496 char ccname[1024]; /* XXX */
499 inbuf.data = (char *)data;
502 pwd = getpwnam (UserNameRequested);
506 snprintf (ccname, sizeof(ccname),
507 "FILE:/tmp/krb5cc_%u", pwd->pw_uid);
509 ret = krb5_cc_resolve (context, ccname, &ccache);
512 printf ("Kerberos V5: could not get ccache: %s\r\n",
513 krb5_get_err_text(context, ret));
517 ret = krb5_cc_initialize (context,
522 printf ("Kerberos V5: could not init ccache: %s\r\n",
523 krb5_get_err_text(context, ret));
528 esetenv("KRB5CCNAME", ccname, 1);
530 ret = krb5_rd_cred2 (context,
538 "Read forwarded creds failed: %s",
539 krb5_get_err_text (context, ret));
541 Data(ap, KRB_FORWARD_REJECT, NULL, 0);
543 Data(ap, KRB_FORWARD_REJECT, errbuf, -1);
545 printf("Could not read forwarded credentials: %s\r\n",
549 Data(ap, KRB_FORWARD_ACCEPT, 0, 0);
554 chown (ccname + 5, pwd->pw_uid, -1);
556 printf("Forwarded credentials obtained\r\n");
561 printf("Unknown Kerberos option %d\r\n", data[-1]);
562 Data(ap, KRB_REJECT, 0, 0);
568 kerberos5_reply(Authenticator *ap, unsigned char *data, int cnt)
570 static int mutual_complete = 0;
577 printf("[ Kerberos V5 refuses authentication because %.*s ]\r\n",
580 printf("[ Kerberos V5 refuses authentication ]\r\n");
586 krb5_keyblock *keyblock;
588 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL &&
590 printf("[ Kerberos V5 accepted you, but didn't provide mutual authentication! ]\r\n");
595 printf("[ Kerberos V5 accepts you as ``%.*s'' ]\r\n", cnt, data);
597 printf("[ Kerberos V5 accepts you ]\r\n");
599 ret = krb5_auth_con_getlocalsubkey (context,
603 ret = krb5_auth_con_getkey (context,
607 printf("[ krb5_auth_con_getkey: %s ]\r\n",
608 krb5_get_err_text(context, ret));
615 skey.data = keyblock->keyvalue.data;
616 encrypt_session_key(&skey, 0);
617 krb5_free_keyblock_contents (context, keyblock);
618 auth_finished(ap, AUTH_USER);
619 if (forward_flags & OPTS_FORWARD_CREDS)
620 kerberos5_forward(ap);
624 if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
625 /* the rest of the reply should contain a krb_ap_rep */
626 krb5_ap_rep_enc_part *reply;
631 inbuf.data = (char *)data;
633 ret = krb5_rd_rep(context, auth_context, &inbuf, &reply);
635 printf("[ Mutual authentication failed: %s ]\r\n",
636 krb5_get_err_text (context, ret));
640 krb5_free_ap_rep_enc_part(context, reply);
644 case KRB_FORWARD_ACCEPT:
645 printf("[ Kerberos V5 accepted forwarded credentials ]\r\n");
647 case KRB_FORWARD_REJECT:
648 printf("[ Kerberos V5 refuses forwarded credentials because %.*s ]\r\n",
653 printf("Unknown Kerberos option %d\r\n", data[-1]);
659 kerberos5_status(Authenticator *ap __unused, char *name, int level)
661 if (level < AUTH_USER)
664 if (UserNameRequested &&
665 krb5_kuserok(context,
669 strcpy(name, UserNameRequested);
675 #define BUMP(buf, len) while (*(buf)) {++(buf), --(len);}
676 #define ADDC(buf, len, c) if ((len) > 0) {*(buf)++ = (c); --(len);}
679 kerberos5_printsub(unsigned char *data, int cnt, unsigned char *buf, int buflen)
683 buf[buflen-1] = '\0'; /* make sure its NULL terminated */
687 case KRB_REJECT: /* Rejected (reason might follow) */
688 strlcpy((char *)buf, " REJECT ", buflen);
691 case KRB_ACCEPT: /* Accepted (name might follow) */
692 strlcpy((char *)buf, " ACCEPT ", buflen);
697 ADDC(buf, buflen, '"');
698 for (i = 4; i < cnt; i++)
699 ADDC(buf, buflen, data[i]);
700 ADDC(buf, buflen, '"');
701 ADDC(buf, buflen, '\0');
705 case KRB_AUTH: /* Authentication data follows */
706 strlcpy((char *)buf, " AUTH", buflen);
710 strlcpy((char *)buf, " RESPONSE", buflen);
713 case KRB_FORWARD: /* Forwarded credentials follow */
714 strlcpy((char *)buf, " FORWARD", buflen);
717 case KRB_FORWARD_ACCEPT: /* Forwarded credentials accepted */
718 strlcpy((char *)buf, " FORWARD_ACCEPT", buflen);
721 case KRB_FORWARD_REJECT: /* Forwarded credentials rejected */
722 /* (reason might follow) */
723 strlcpy((char *)buf, " FORWARD_REJECT", buflen);
727 snprintf(buf, buflen, " %d (unknown)", data[3]);
730 for (i = 4; i < cnt; i++) {
731 snprintf(buf, buflen, " %d", data[i]);
739 kerberos5_forward(Authenticator *ap)
744 krb5_kdc_flags flags;
746 krb5_principal principal;
748 ret = krb5_cc_default (context, &ccache);
751 printf ("KerberosV5: could not get default ccache: %s\r\n",
752 krb5_get_err_text (context, ret));
756 ret = krb5_cc_get_principal (context, ccache, &principal);
759 printf ("KerberosV5: could not get principal: %s\r\n",
760 krb5_get_err_text (context, ret));
764 memset (&creds, 0, sizeof(creds));
766 creds.client = principal;
768 ret = krb5_build_principal (context,
770 strlen(principal->realm),
778 printf ("KerberosV5: could not get principal: %s\r\n",
779 krb5_get_err_text (context, ret));
783 creds.times.endtime = 0;
786 flags.b.forwarded = 1;
787 if (forward_flags & OPTS_FORWARDABLE_CREDS)
788 flags.b.forwardable = 1;
790 ret = krb5_get_forwarded_creds (context,
799 printf ("Kerberos V5: error getting forwarded creds: %s\r\n",
800 krb5_get_err_text (context, ret));
804 if(!Data(ap, KRB_FORWARD, out_data.data, out_data.length)) {
806 printf("Not enough room for authentication data\r\n");
809 printf("Forwarded local Kerberos V5 credentials to server\r\n");
814 /* if this was a K5 authentication try and join a PAG for the user. */
816 kerberos5_dfspag(void)
819 dfspag = krb5_dfs_pag(context, dfsfwd, ticket->client,