xref: /freebsd/sys/kgssapi/gss_impl.c (revision 4602d45eb3b1d33e0ea0d97c4d18033af95d7fca)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5  * Authors: Doug Rabson <dfr@rabson.org>
6  * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
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  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/kobj.h>
33 #include <sys/lock.h>
34 #include <sys/malloc.h>
35 #include <sys/module.h>
36 #include <sys/mutex.h>
37 #include <sys/priv.h>
38 #include <sys/proc.h>
39 
40 #include <kgssapi/gssapi.h>
41 #include <kgssapi/gssapi_impl.h>
42 #include <rpc/rpc.h>
43 #include <rpc/rpc_com.h>
44 #include <rpc/rpcsec_gss.h>
45 
46 #include "gssd.h"
47 #include "kgss_if.h"
48 
49 MALLOC_DEFINE(M_GSSAPI, "GSS-API", "GSS-API");
50 
51 struct kgss_mech_list kgss_mechs;
52 struct mtx kgss_gssd_lock;
53 
54 CLIENT *kgss_gssd_handle;
55 
56 static int
kgss_load(void)57 kgss_load(void)
58 {
59 	CLIENT *cl;
60 
61 	LIST_INIT(&kgss_mechs);
62 
63 	cl = client_nl_create("kgss", GSSD, GSSDVERS);
64 	KASSERT(cl, ("%s: netlink client already exist", __func__));
65 
66 	/*
67 	 * The transport default is no retries at all, since there could
68 	 * be no userland listener to our messages.  We will retry for 5
69 	 * minutes with 10 second interval.  This will potentially cure hosts
70 	 * with misconfigured startup, where kernel starts sending GSS queries
71 	 * before userland had started up the gssd(8) daemon.
72 	 */
73 	clnt_control(cl, CLSET_RETRIES, &(int){30});
74 	clnt_control(cl, CLSET_TIMEOUT, &(struct timeval){.tv_sec = 300});
75 
76 	/*
77 	 * We literally wait on gssd(8), let's see that in top(1).
78 	 */
79 	clnt_control(cl, CLSET_WAITCHAN, "gssd");
80 
81 	mtx_lock(&kgss_gssd_lock);
82 	kgss_gssd_handle = cl;
83 	mtx_unlock(&kgss_gssd_lock);
84 
85 	return (0);
86 }
87 
88 #if 0
89 static void
90 kgss_unload(void)
91 {
92 
93 	clnt_destroy(kgss_gssd_handle);
94 }
95 #endif
96 
97 int
kgss_oid_equal(const gss_OID oid1,const gss_OID oid2)98 kgss_oid_equal(const gss_OID oid1, const gss_OID oid2)
99 {
100 
101 	if (oid1 == oid2)
102 		return (1);
103 	if (!oid1 || !oid2)
104 		return (0);
105 	if (oid1->length != oid2->length)
106 		return (0);
107 	if (memcmp(oid1->elements, oid2->elements, oid1->length))
108 		return (0);
109 	return (1);
110 }
111 
112 void
kgss_install_mech(gss_OID mech_type,const char * name,struct kobj_class * cls)113 kgss_install_mech(gss_OID mech_type, const char *name, struct kobj_class *cls)
114 {
115 	struct kgss_mech *km;
116 
117 	km = malloc(sizeof(struct kgss_mech), M_GSSAPI, M_WAITOK);
118 	km->km_mech_type = mech_type;
119 	km->km_mech_name = name;
120 	km->km_class = cls;
121 	LIST_INSERT_HEAD(&kgss_mechs, km, km_link);
122 }
123 
124 void
kgss_uninstall_mech(gss_OID mech_type)125 kgss_uninstall_mech(gss_OID mech_type)
126 {
127 	struct kgss_mech *km;
128 
129 	LIST_FOREACH(km, &kgss_mechs, km_link) {
130 		if (kgss_oid_equal(km->km_mech_type, mech_type)) {
131 			LIST_REMOVE(km, km_link);
132 			free(km, M_GSSAPI);
133 			return;
134 		}
135 	}
136 }
137 
138 gss_OID
kgss_find_mech_by_name(const char * name)139 kgss_find_mech_by_name(const char *name)
140 {
141 	struct kgss_mech *km;
142 
143 	LIST_FOREACH(km, &kgss_mechs, km_link) {
144 		if (!strcmp(km->km_mech_name, name)) {
145 			return (km->km_mech_type);
146 		}
147 	}
148 	return (GSS_C_NO_OID);
149 }
150 
151 const char *
kgss_find_mech_by_oid(const gss_OID oid)152 kgss_find_mech_by_oid(const gss_OID oid)
153 {
154 	struct kgss_mech *km;
155 
156 	LIST_FOREACH(km, &kgss_mechs, km_link) {
157 		if (kgss_oid_equal(km->km_mech_type, oid)) {
158 			return (km->km_mech_name);
159 		}
160 	}
161 	return (NULL);
162 }
163 
164 gss_ctx_id_t
kgss_create_context(gss_OID mech_type)165 kgss_create_context(gss_OID mech_type)
166 {
167 	struct kgss_mech *km;
168 	gss_ctx_id_t ctx;
169 
170 	LIST_FOREACH(km, &kgss_mechs, km_link) {
171 		if (kgss_oid_equal(km->km_mech_type, mech_type))
172 			break;
173 	}
174 	if (!km)
175 		return (NULL);
176 
177 	ctx = (gss_ctx_id_t) kobj_create(km->km_class, M_GSSAPI, M_WAITOK);
178 	KGSS_INIT(ctx);
179 
180 	return (ctx);
181 }
182 
183 void
kgss_delete_context(gss_ctx_id_t ctx,gss_buffer_t output_token)184 kgss_delete_context(gss_ctx_id_t ctx, gss_buffer_t output_token)
185 {
186 
187 	KGSS_DELETE(ctx, output_token);
188 	kobj_delete((kobj_t) ctx, M_GSSAPI);
189 }
190 
191 OM_uint32
kgss_transfer_context(gss_ctx_id_t ctx,void * lctx)192 kgss_transfer_context(gss_ctx_id_t ctx, void *lctx)
193 {
194 	struct export_sec_context_res res;
195 	struct export_sec_context_args args;
196 	enum clnt_stat stat;
197 	OM_uint32 maj_stat;
198 
199 	if (lctx != NULL) {
200 		maj_stat = KGSS_IMPORT(ctx, MIT_V1, lctx);
201 		ctx->handle = 0;
202 		return (maj_stat);
203 	}
204 
205 	args.ctx = ctx->handle;
206 	bzero(&res, sizeof(res));
207 	stat = gssd_export_sec_context_1(&args, &res, kgss_gssd_handle);
208 	if (stat != RPC_SUCCESS) {
209 		return (GSS_S_FAILURE);
210 	}
211 
212 	maj_stat = KGSS_IMPORT(ctx, res.format, &res.interprocess_token);
213 	ctx->handle = 0;
214 
215 	xdr_free((xdrproc_t) xdr_export_sec_context_res, &res);
216 
217 	return (maj_stat);
218 }
219 
220 void
kgss_copy_buffer(const gss_buffer_t from,gss_buffer_t to)221 kgss_copy_buffer(const gss_buffer_t from, gss_buffer_t to)
222 {
223 	to->length = from->length;
224 	if (from->length) {
225 		to->value = malloc(from->length, M_GSSAPI, M_WAITOK);
226 		bcopy(from->value, to->value, from->length);
227 	} else {
228 		to->value = NULL;
229 	}
230 }
231 
232 /*
233  * Acquire the kgss_gssd_handle and return it with a reference count,
234  * if it is available.
235  */
236 CLIENT *
kgss_gssd_client(void)237 kgss_gssd_client(void)
238 {
239 	CLIENT *cl;
240 
241 	mtx_lock(&kgss_gssd_lock);
242 	cl = kgss_gssd_handle;
243 	if (cl != NULL)
244 		CLNT_ACQUIRE(cl);
245 	mtx_unlock(&kgss_gssd_lock);
246 	return (cl);
247 }
248 
249 /*
250  * Kernel module glue
251  */
252 static int
kgssapi_modevent(module_t mod,int type,void * data)253 kgssapi_modevent(module_t mod, int type, void *data)
254 {
255 	int error = 0;
256 
257 	switch (type) {
258 	case MOD_LOAD:
259 		rpc_gss_entries.rpc_gss_refresh_auth = rpc_gss_refresh_auth;
260 		rpc_gss_entries.rpc_gss_secfind = rpc_gss_secfind;
261 		rpc_gss_entries.rpc_gss_secpurge = rpc_gss_secpurge;
262 		rpc_gss_entries.rpc_gss_seccreate = rpc_gss_seccreate;
263 		rpc_gss_entries.rpc_gss_set_defaults = rpc_gss_set_defaults;
264 		rpc_gss_entries.rpc_gss_max_data_length =
265 		    rpc_gss_max_data_length;
266 		rpc_gss_entries.rpc_gss_get_error = rpc_gss_get_error;
267 		rpc_gss_entries.rpc_gss_mech_to_oid = rpc_gss_mech_to_oid;
268 		rpc_gss_entries.rpc_gss_oid_to_mech = rpc_gss_oid_to_mech;
269 		rpc_gss_entries.rpc_gss_qop_to_num = rpc_gss_qop_to_num;
270 		rpc_gss_entries.rpc_gss_get_mechanisms = rpc_gss_get_mechanisms;
271 		rpc_gss_entries.rpc_gss_get_versions = rpc_gss_get_versions;
272 		rpc_gss_entries.rpc_gss_is_installed = rpc_gss_is_installed;
273 		rpc_gss_entries.rpc_gss_set_svc_name = rpc_gss_set_svc_name;
274 		rpc_gss_entries.rpc_gss_clear_svc_name = rpc_gss_clear_svc_name;
275 		rpc_gss_entries.rpc_gss_getcred = rpc_gss_getcred;
276 		rpc_gss_entries.rpc_gss_set_callback = rpc_gss_set_callback;
277 		rpc_gss_entries.rpc_gss_clear_callback = rpc_gss_clear_callback;
278 		rpc_gss_entries.rpc_gss_get_principal_name =
279 		    rpc_gss_get_principal_name;
280 		rpc_gss_entries.rpc_gss_svc_max_data_length =
281 		    rpc_gss_svc_max_data_length;
282 		rpc_gss_entries.rpc_gss_ip_to_srv_principal =
283 		    rpc_gss_ip_to_srv_principal;
284 		mtx_init(&kgss_gssd_lock, "kgss_gssd_lock", NULL, MTX_DEF);
285 		error = kgss_load();
286 		break;
287 	case MOD_UNLOAD:
288 #if 0
289 		kgss_unload();
290 		mtx_destroy(&kgss_gssd_lock);
291 #endif
292 		/*
293 		 * Unloading of the kgssapi module is not currently supported.
294 		 * If somebody wants this, we would need to keep track of
295 		 * currently executing threads and make sure the count is 0.
296 		 */
297 		/* FALLTHROUGH */
298 	default:
299 		error = EOPNOTSUPP;
300 	}
301 	return (error);
302 }
303 static moduledata_t kgssapi_mod = {
304 	"kgssapi",
305 	kgssapi_modevent,
306 	NULL,
307 };
308 DECLARE_MODULE(kgssapi, kgssapi_mod, SI_SUB_VFS, SI_ORDER_SECOND);
309 MODULE_DEPEND(kgssapi, xdr, 1, 1, 1);
310 MODULE_DEPEND(kgssapi, krpc, 1, 1, 1);
311 MODULE_VERSION(kgssapi, 1);
312