xref: /netbsd-src/crypto/external/bsd/heimdal/dist/kuser/kgetcred.c (revision afab4e300d3a9fb07dd8c80daf53d0feb3345706)
1 /*	$NetBSD: kgetcred.c,v 1.4 2023/06/19 21:41:42 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "kuser_locl.h"
37 
38 static char *cache_str;
39 static char *out_cache_str;
40 static char *delegation_cred_str;
41 static char *etype_str;
42 static int transit_flag = 1;
43 static int forwardable_flag;
44 static int canonicalize_flag;
45 static int is_hostbased_flag;
46 static int is_canonical_flag;
47 static char *impersonate_str;
48 static char *nametype_str;
49 static int store_flag = 1;
50 static int cached_only_flag;
51 static int anonymous_flag;
52 static int debug_flag;
53 static int version_flag;
54 static int help_flag;
55 
56 struct getargs args[] = {
57     { "cache",		'c', arg_string, &cache_str,
58       NP_("credential cache to use", ""), "cache"},
59     { "out-cache",	0,   arg_string, &out_cache_str,
60       NP_("credential cache to store credential in", ""), "cache"},
61     { "delegation-credential-cache",0,arg_string, &delegation_cred_str,
62       NP_("where to find the ticket use for delegation", ""), "cache"},
63     { "canonicalize",	0, arg_flag, &canonicalize_flag,
64       NP_("canonicalize the principal (chase referrals)", ""), NULL },
65     { "canonical",	0,   arg_flag, &is_canonical_flag,
66       NP_("the name components are canonical", ""), NULL },
67     { "forwardable",	0,   arg_flag, &forwardable_flag,
68       NP_("forwardable ticket requested", ""), NULL},
69     { "transit-check",	0,   arg_negative_flag, &transit_flag, NULL, NULL },
70     { "enctype",	'e', arg_string, &etype_str,
71       NP_("encryption type to use", ""), "enctype"},
72     { "impersonate",	0,   arg_string, &impersonate_str,
73       NP_("client to impersonate", ""), "principal"},
74     { "name-type",	0,   arg_string, &nametype_str,
75       NP_("Kerberos name type", ""), NULL },
76     { "hostbased",	'H', arg_flag, &is_hostbased_flag,
77       NP_("indicate that the name is a host-based service name", ""), NULL },
78     { "store", 	        0,   arg_negative_flag, &store_flag,
79       NP_("don't store the tickets obtained in the cache", ""), NULL },
80     { "cached-only", 	        0,   arg_flag, &cached_only_flag,
81       NP_("don't talk to the KDC, just search the cache", ""), NULL },
82     { "anonymous",      'n',   arg_flag, &anonymous_flag,
83       NP_("request an anonymous ticket", ""), NULL },
84     { "debug", 	        0,   arg_flag, &debug_flag, NULL, NULL },
85     { "version", 	0,   arg_flag, &version_flag, NULL, NULL },
86     { "help",		0,   arg_flag, &help_flag, NULL, NULL }
87 };
88 
89 static void
usage(int ret)90 usage(int ret)
91 {
92     arg_printusage(args,
93 		   sizeof(args)/sizeof(*args),
94 		   NULL,
95 		   "service");
96     exit (ret);
97 }
98 
99 int
main(int argc,char ** argv)100 main(int argc, char **argv)
101 {
102     krb5_error_code ret;
103     krb5_context context;
104     krb5_ccache cache;
105     krb5_creds *out;
106     int optidx = 0;
107     int32_t nametype = KRB5_NT_UNKNOWN;
108     krb5_get_creds_opt opt;
109     krb5_principal server = NULL;
110     krb5_principal impersonate;
111 
112     setprogname(argv[0]);
113 
114     ret = krb5_init_context(&context);
115     if (ret)
116 	errx(1, "krb5_init_context failed: %d", ret);
117 
118     if (getarg(args, sizeof(args) / sizeof(args[0]), argc, argv, &optidx))
119 	usage(1);
120 
121     if (help_flag)
122 	usage (0);
123 
124     if (version_flag) {
125 	print_version(NULL);
126 	exit(0);
127     }
128 
129     argc -= optidx;
130     argv += optidx;
131 
132     if (debug_flag) {
133         ret = krb5_set_debug_dest(context, getprogname(), "STDERR");
134         if (ret)
135             krb5_warn(context, ret, "krb5_set_debug_dest");
136     }
137 
138     if (cache_str) {
139 	ret = krb5_cc_resolve(context, cache_str, &cache);
140 	if (ret)
141 	    krb5_err(context, 1, ret, "%s", cache_str);
142     } else {
143 	ret = krb5_cc_default (context, &cache);
144 	if (ret)
145 	    krb5_err(context, 1, ret, "krb5_cc_resolve");
146     }
147 
148     ret = krb5_get_creds_opt_alloc(context, &opt);
149     if (ret)
150 	krb5_err(context, 1, ret, "krb5_get_creds_opt_alloc");
151 
152     if (etype_str) {
153 	krb5_enctype enctype;
154 
155 	ret = krb5_string_to_enctype(context, etype_str, &enctype);
156 	if (ret)
157 	    krb5_errx(context, 1, N_("unrecognized enctype: %s", ""),
158 		      etype_str);
159 	krb5_get_creds_opt_set_enctype(context, opt, enctype);
160     }
161 
162     if (impersonate_str) {
163 	ret = krb5_parse_name(context, impersonate_str, &impersonate);
164 	if (ret)
165 	    krb5_err(context, 1, ret, "krb5_parse_name %s", impersonate_str);
166 	krb5_get_creds_opt_set_impersonate(context, opt, impersonate);
167 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_NO_STORE);
168         krb5_free_principal(context, impersonate);
169     }
170 
171     if (out_cache_str)
172 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_NO_STORE);
173 
174     if (forwardable_flag)
175 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_FORWARDABLE);
176     if (!transit_flag)
177 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_NO_TRANSIT_CHECK);
178     if (canonicalize_flag)
179 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_CANONICALIZE);
180     if (!store_flag)
181 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_NO_STORE);
182     if (cached_only_flag)
183 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_CACHED);
184     if (anonymous_flag)
185 	krb5_get_creds_opt_add_options(context, opt, KRB5_GC_ANONYMOUS);
186 
187     if (delegation_cred_str) {
188 	krb5_ccache id;
189 	krb5_creds c, mc;
190 	Ticket ticket;
191 
192 	krb5_cc_clear_mcred(&mc);
193 	ret = krb5_cc_get_principal(context, cache, &mc.server);
194 	if (ret)
195 	    krb5_err(context, 1, ret, "krb5_cc_get_principal");
196 
197 	ret = krb5_cc_resolve(context, delegation_cred_str, &id);
198 	if(ret)
199 	    krb5_err(context, 1, ret, "krb5_cc_resolve");
200 
201 	ret = krb5_cc_retrieve_cred(context, id, 0, &mc, &c);
202 	if(ret)
203 	    krb5_err(context, 1, ret, "krb5_cc_retrieve_cred");
204 
205 	ret = decode_Ticket(c.ticket.data, c.ticket.length, &ticket, NULL);
206 	if (ret) {
207 	    krb5_clear_error_message(context);
208 	    krb5_err(context, 1, ret, "decode_Ticket");
209 	}
210 	krb5_free_cred_contents(context, &c);
211 
212 	ret = krb5_get_creds_opt_set_ticket(context, opt, &ticket);
213 	if(ret)
214 	    krb5_err(context, 1, ret, "krb5_get_creds_opt_set_ticket");
215 	free_Ticket(&ticket);
216 
217 	krb5_cc_close(context, id);
218 	krb5_free_principal(context, mc.server);
219 
220 	krb5_get_creds_opt_add_options(context, opt,
221 				       KRB5_GC_CONSTRAINED_DELEGATION);
222     }
223 
224     if (nametype_str != NULL) {
225         ret = krb5_parse_nametype(context, nametype_str, &nametype);
226         if (ret)
227             krb5_err(context, 1, ret, "krb5_parse_nametype");
228     }
229 
230     if (nametype == KRB5_NT_SRV_HST ||
231         nametype == KRB5_NT_SRV_HST_NEEDS_CANON)
232         is_hostbased_flag = 1;
233 
234     if (is_hostbased_flag) {
235 	const char *sname = NULL;
236 	const char *hname = NULL;
237 
238         if (nametype_str != NULL &&
239             nametype != KRB5_NT_SRV_HST &&
240             nametype != KRB5_NT_SRV_HST_NEEDS_CANON)
241             krb5_errx(context, 1, "--hostbased not compatible with "
242                       "non-hostbased --name-type");
243 
244         if (is_canonical_flag)
245             nametype = KRB5_NT_SRV_HST;
246         else
247             nametype = KRB5_NT_SRV_HST_NEEDS_CANON;
248 
249         /*
250          * Host-based service names can have more than one component.
251          *
252          * RFC5179 did not, but should have, assign a Kerberos name-type
253          * corresponding to GSS_C_NT_DOMAINBASED.  But it's basically a
254          * host-based service name type with one additional component.
255          *
256          * So that's how we're treating host-based service names here:
257          * two or more components.
258          */
259 
260         if (argc == 0) {
261             usage(1);
262         } else if (argc == 1) {
263             krb5_principal server2;
264 
265             /*
266              * In this case the one argument is a principal name, not the
267              * service name.
268              *
269              * We parse the argument as a principal name, extract the service
270              * and hostname components, use krb5_sname_to_principal(), then
271              * extract the service and hostname components from that.
272              */
273 
274             ret = krb5_parse_name(context, argv[0], &server);
275             if (ret)
276                 krb5_err(context, 1, ret, "krb5_parse_name %s", argv[0]);
277             sname = krb5_principal_get_comp_string(context, server, 0);
278 
279             /*
280              * If a single-component principal name is given, then we'll
281              * default the hostname, as krb5_principal_get_comp_string()
282              * returns NULL in this case.
283              */
284             hname = krb5_principal_get_comp_string(context, server, 1);
285 
286 	    ret = krb5_sname_to_principal(context, hname, sname,
287 					   KRB5_NT_SRV_HST, &server2);
288             if (ret)
289                 krb5_err(context, 1, ret, "krb5_sname_to_principal %s %s",
290                          sname, hname);
291             sname = krb5_principal_get_comp_string(context, server2, 0);
292             hname = krb5_principal_get_comp_string(context, server2, 1);
293 
294             /*
295              * Modify the original with the new sname/hname.  This way we
296              * retain any additional principal name components from the given
297              * principal name.
298              *
299              * The name-type is set further below.
300              */
301             ret = krb5_principal_set_comp_string(context, server, 0, sname);
302             if (ret)
303                 krb5_err(context, 1, ret, "krb5_principal_set_comp_string %s", argv[0]);
304             ret = krb5_principal_set_comp_string(context, server, 1, hname);
305             if (ret)
306                 krb5_err(context, 1, ret, "krb5_principal_set_comp_string %s", argv[0]);
307             krb5_free_principal(context, server2);
308         } else {
309             size_t i;
310 
311             /*
312              * In this case the arguments are principal name components.
313              *
314              * The service and hostname components can be defaulted by passing
315              * empty strings.
316              */
317 	    sname = argv[0];
318             if (*sname == '\0')
319                 sname = NULL;
320 	    hname = argv[1];
321             if (hname == NULL || *hname == '\0')
322                 hname = NULL;
323 	    ret = krb5_sname_to_principal(context, hname, sname,
324                                           KRB5_NT_SRV_HST, &server);
325 	    if (ret)
326 		krb5_err(context, 1, ret, "krb5_sname_to_principal");
327 
328             for (i = 2; i < argc; i++) {
329                 ret = krb5_principal_set_comp_string(context, server, i, argv[i]);
330                 if (ret)
331                     krb5_err(context, 1, ret, "krb5_principal_set_comp_string");
332             }
333 	}
334     } else if (argc == 1) {
335 	ret = krb5_parse_name(context, argv[0], &server);
336 	if (ret)
337 	    krb5_err(context, 1, ret, "krb5_parse_name %s", argv[0]);
338     } else {
339 	usage(1);
340     }
341 
342     if (nametype != KRB5_NT_UNKNOWN)
343         server->name.name_type = (NAME_TYPE)nametype;
344 
345     ret = krb5_get_creds(context, opt, cache, server, &out);
346     if (ret)
347 	krb5_err(context, 1, ret, "krb5_get_creds");
348 
349     if (out_cache_str) {
350 	krb5_ccache id;
351 
352 	ret = krb5_cc_resolve(context, out_cache_str, &id);
353 	if(ret)
354 	    krb5_err(context, 1, ret, "krb5_cc_resolve");
355 
356 	ret = krb5_cc_initialize(context, id, out->client);
357 	if(ret)
358 	    krb5_err(context, 1, ret, "krb5_cc_initialize");
359 
360 	ret = krb5_cc_store_cred(context, id, out);
361 	if(ret)
362 	    krb5_err(context, 1, ret, "krb5_cc_store_cred");
363 	krb5_cc_close(context, id);
364     }
365 
366     krb5_free_creds(context, out);
367     krb5_free_principal(context, server);
368     krb5_get_creds_opt_free(context, opt);
369     krb5_cc_close (context, cache);
370     krb5_free_context (context);
371 
372     return 0;
373 }
374