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/jail.h>
32#include <sys/kernel.h>
33#include <sys/kobj.h>
34#include <sys/lock.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37#include <sys/mutex.h>
38#include <sys/priv.h>
39#include <sys/proc.h>
40#include <sys/syscall.h>
41#include <sys/sysent.h>
42#include <sys/sysproto.h>
43
44#include <kgssapi/gssapi.h>
45#include <kgssapi/gssapi_impl.h>
46#include <rpc/rpc.h>
47#include <rpc/rpc_com.h>
48#include <rpc/rpcsec_gss.h>
49
50#include "gssd.h"
51#include "kgss_if.h"
52
53MALLOC_DEFINE(M_GSSAPI, "GSS-API", "GSS-API");
54
55/*
56 * Syscall hooks
57 */
58static struct syscall_helper_data gssd_syscalls[] = {
59	SYSCALL_INIT_HELPER(gssd_syscall),
60	SYSCALL_INIT_LAST
61};
62
63struct kgss_mech_list kgss_mechs;
64struct mtx kgss_gssd_lock;
65
66KGSS_VNET_DEFINE(CLIENT *, kgss_gssd_handle) = NULL;
67
68static int
69kgss_load(void)
70{
71	int error;
72
73	LIST_INIT(&kgss_mechs);
74	error = syscall_helper_register(gssd_syscalls, SY_THR_STATIC_KLD);
75	if (error != 0)
76		return (error);
77	return (0);
78}
79
80static void
81kgss_unload(void)
82{
83
84	syscall_helper_unregister(gssd_syscalls);
85}
86
87int
88sys_gssd_syscall(struct thread *td, struct gssd_syscall_args *uap)
89{
90        struct sockaddr_un sun;
91        struct netconfig *nconf;
92	char path[MAXPATHLEN];
93	int error;
94	CLIENT *cl, *oldcl;
95
96	error = priv_check(td, PRIV_NFS_DAEMON);
97	if (error)
98		return (error);
99
100	error = copyinstr(uap->path, path, sizeof(path), NULL);
101	if (error)
102		return (error);
103	if (strlen(path) + 1 > sizeof(sun.sun_path))
104		return (EINVAL);
105
106	if (path[0] != '\0') {
107		sun.sun_family = AF_LOCAL;
108		strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
109		sun.sun_len = SUN_LEN(&sun);
110
111		nconf = getnetconfigent("local");
112		cl = clnt_reconnect_create(nconf,
113		    (struct sockaddr *) &sun, GSSD, GSSDVERS,
114		    RPC_MAXDATASIZE, RPC_MAXDATASIZE);
115		/*
116		 * The number of retries defaults to INT_MAX, which effectively
117		 * means an infinite, uninterruptable loop.  Limiting it to
118		 * five retries keeps it from running forever.
119		 */
120		if (cl != NULL) {
121			int retry_count = 5;
122			struct timeval timo;
123			CLNT_CONTROL(cl, CLSET_RETRIES, &retry_count);
124
125			/*
126			 * Set the timeout for an upcall to 5 minutes.  The
127			 * default of 25 seconds is not long enough for some
128			 * gss_XXX() calls done by the gssd(8) daemon.
129			 */
130			timo.tv_sec = 5 * 60;
131			timo.tv_usec = 0;
132			CLNT_CONTROL(cl, CLSET_TIMEOUT, &timo);
133		}
134	} else
135		cl = NULL;
136
137	KGSS_CURVNET_SET_QUIET(KGSS_TD_TO_VNET(curthread));
138	mtx_lock(&kgss_gssd_lock);
139	oldcl = KGSS_VNET(kgss_gssd_handle);
140	KGSS_VNET(kgss_gssd_handle) = cl;
141	mtx_unlock(&kgss_gssd_lock);
142	KGSS_CURVNET_RESTORE();
143
144	if (oldcl != NULL) {
145		CLNT_CLOSE(oldcl);
146		CLNT_RELEASE(oldcl);
147	}
148
149	return (0);
150}
151
152int
153kgss_oid_equal(const gss_OID oid1, const gss_OID oid2)
154{
155
156	if (oid1 == oid2)
157		return (1);
158	if (!oid1 || !oid2)
159		return (0);
160	if (oid1->length != oid2->length)
161		return (0);
162	if (memcmp(oid1->elements, oid2->elements, oid1->length))
163		return (0);
164	return (1);
165}
166
167void
168kgss_install_mech(gss_OID mech_type, const char *name, struct kobj_class *cls)
169{
170	struct kgss_mech *km;
171
172	km = malloc(sizeof(struct kgss_mech), M_GSSAPI, M_WAITOK);
173	km->km_mech_type = mech_type;
174	km->km_mech_name = name;
175	km->km_class = cls;
176	LIST_INSERT_HEAD(&kgss_mechs, km, km_link);
177}
178
179void
180kgss_uninstall_mech(gss_OID mech_type)
181{
182	struct kgss_mech *km;
183
184	LIST_FOREACH(km, &kgss_mechs, km_link) {
185		if (kgss_oid_equal(km->km_mech_type, mech_type)) {
186			LIST_REMOVE(km, km_link);
187			free(km, M_GSSAPI);
188			return;
189		}
190	}
191}
192
193gss_OID
194kgss_find_mech_by_name(const char *name)
195{
196	struct kgss_mech *km;
197
198	LIST_FOREACH(km, &kgss_mechs, km_link) {
199		if (!strcmp(km->km_mech_name, name)) {
200			return (km->km_mech_type);
201		}
202	}
203	return (GSS_C_NO_OID);
204}
205
206const char *
207kgss_find_mech_by_oid(const gss_OID oid)
208{
209	struct kgss_mech *km;
210
211	LIST_FOREACH(km, &kgss_mechs, km_link) {
212		if (kgss_oid_equal(km->km_mech_type, oid)) {
213			return (km->km_mech_name);
214		}
215	}
216	return (NULL);
217}
218
219gss_ctx_id_t
220kgss_create_context(gss_OID mech_type)
221{
222	struct kgss_mech *km;
223	gss_ctx_id_t ctx;
224
225	LIST_FOREACH(km, &kgss_mechs, km_link) {
226		if (kgss_oid_equal(km->km_mech_type, mech_type))
227			break;
228	}
229	if (!km)
230		return (NULL);
231
232	ctx = (gss_ctx_id_t) kobj_create(km->km_class, M_GSSAPI, M_WAITOK);
233	KGSS_INIT(ctx);
234
235	return (ctx);
236}
237
238void
239kgss_delete_context(gss_ctx_id_t ctx, gss_buffer_t output_token)
240{
241
242	KGSS_DELETE(ctx, output_token);
243	kobj_delete((kobj_t) ctx, M_GSSAPI);
244}
245
246OM_uint32
247kgss_transfer_context(gss_ctx_id_t ctx)
248{
249	struct export_sec_context_res res;
250	struct export_sec_context_args args;
251	enum clnt_stat stat;
252	OM_uint32 maj_stat;
253
254	KGSS_CURVNET_SET_QUIET(KGSS_TD_TO_VNET(curthread));
255	if (!KGSS_VNET(kgss_gssd_handle)) {
256		KGSS_CURVNET_RESTORE();
257		return (GSS_S_FAILURE);
258	}
259
260	args.ctx = ctx->handle;
261	bzero(&res, sizeof(res));
262	stat = gssd_export_sec_context_1(&args, &res, KGSS_VNET(kgss_gssd_handle));
263	KGSS_CURVNET_RESTORE();
264	if (stat != RPC_SUCCESS) {
265		return (GSS_S_FAILURE);
266	}
267
268	maj_stat = KGSS_IMPORT(ctx, res.format, &res.interprocess_token);
269	ctx->handle = 0;
270
271	xdr_free((xdrproc_t) xdr_export_sec_context_res, &res);
272
273	return (maj_stat);
274}
275
276void
277kgss_copy_buffer(const gss_buffer_t from, gss_buffer_t to)
278{
279	to->length = from->length;
280	if (from->length) {
281		to->value = malloc(from->length, M_GSSAPI, M_WAITOK);
282		bcopy(from->value, to->value, from->length);
283	} else {
284		to->value = NULL;
285	}
286}
287
288/*
289 * Acquire the kgss_gssd_handle and return it with a reference count,
290 * if it is available.
291 */
292CLIENT *
293kgss_gssd_client(void)
294{
295	CLIENT *cl;
296
297	KGSS_CURVNET_SET_QUIET(KGSS_TD_TO_VNET(curthread));
298	mtx_lock(&kgss_gssd_lock);
299	cl = KGSS_VNET(kgss_gssd_handle);
300	if (cl != NULL)
301		CLNT_ACQUIRE(cl);
302	mtx_unlock(&kgss_gssd_lock);
303	KGSS_CURVNET_RESTORE();
304	return (cl);
305}
306
307/*
308 * Kernel module glue
309 */
310static int
311kgssapi_modevent(module_t mod, int type, void *data)
312{
313	int error = 0;
314
315	switch (type) {
316	case MOD_LOAD:
317		rpc_gss_entries.rpc_gss_refresh_auth = rpc_gss_refresh_auth;
318		rpc_gss_entries.rpc_gss_secfind = rpc_gss_secfind;
319		rpc_gss_entries.rpc_gss_secpurge = rpc_gss_secpurge;
320		rpc_gss_entries.rpc_gss_seccreate = rpc_gss_seccreate;
321		rpc_gss_entries.rpc_gss_set_defaults = rpc_gss_set_defaults;
322		rpc_gss_entries.rpc_gss_max_data_length =
323		    rpc_gss_max_data_length;
324		rpc_gss_entries.rpc_gss_get_error = rpc_gss_get_error;
325		rpc_gss_entries.rpc_gss_mech_to_oid = rpc_gss_mech_to_oid;
326		rpc_gss_entries.rpc_gss_oid_to_mech = rpc_gss_oid_to_mech;
327		rpc_gss_entries.rpc_gss_qop_to_num = rpc_gss_qop_to_num;
328		rpc_gss_entries.rpc_gss_get_mechanisms = rpc_gss_get_mechanisms;
329		rpc_gss_entries.rpc_gss_get_versions = rpc_gss_get_versions;
330		rpc_gss_entries.rpc_gss_is_installed = rpc_gss_is_installed;
331		rpc_gss_entries.rpc_gss_set_svc_name = rpc_gss_set_svc_name;
332		rpc_gss_entries.rpc_gss_clear_svc_name = rpc_gss_clear_svc_name;
333		rpc_gss_entries.rpc_gss_getcred = rpc_gss_getcred;
334		rpc_gss_entries.rpc_gss_set_callback = rpc_gss_set_callback;
335		rpc_gss_entries.rpc_gss_clear_callback = rpc_gss_clear_callback;
336		rpc_gss_entries.rpc_gss_get_principal_name =
337		    rpc_gss_get_principal_name;
338		rpc_gss_entries.rpc_gss_svc_max_data_length =
339		    rpc_gss_svc_max_data_length;
340		rpc_gss_entries.rpc_gss_ip_to_srv_principal =
341		    rpc_gss_ip_to_srv_principal;
342		mtx_init(&kgss_gssd_lock, "kgss_gssd_lock", NULL, MTX_DEF);
343		error = kgss_load();
344		break;
345	case MOD_UNLOAD:
346		kgss_unload();
347		mtx_destroy(&kgss_gssd_lock);
348		/*
349		 * Unloading of the kgssapi module is not currently supported.
350		 * If somebody wants this, we would need to keep track of
351		 * currently executing threads and make sure the count is 0.
352		 */
353		/* FALLTHROUGH */
354	default:
355		error = EOPNOTSUPP;
356	}
357	return (error);
358}
359static moduledata_t kgssapi_mod = {
360	"kgssapi",
361	kgssapi_modevent,
362	NULL,
363};
364DECLARE_MODULE(kgssapi, kgssapi_mod, SI_SUB_VFS, SI_ORDER_ANY);
365MODULE_DEPEND(kgssapi, xdr, 1, 1, 1);
366MODULE_DEPEND(kgssapi, krpc, 1, 1, 1);
367MODULE_VERSION(kgssapi, 1);
368