xref: /openbmc/linux/net/sunrpc/auth_gss/gss_mech_switch.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  *  linux/net/sunrpc/gss_mech_switch.c
3  *
4  *  Copyright (c) 2001 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  J. Bruce Fields   <bfields@umich.edu>
8  *
9  *  Redistribution and use in source and binary forms, with or without
10  *  modification, are permitted provided that the following conditions
11  *  are met:
12  *
13  *  1. Redistributions of source code must retain the above copyright
14  *     notice, this list of conditions and the following disclaimer.
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  *  3. Neither the name of the University nor the names of its
19  *     contributors may be used to endorse or promote products derived
20  *     from this software without specific prior written permission.
21  *
22  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
23  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  */
35 
36 #include <linux/types.h>
37 #include <linux/slab.h>
38 #include <linux/socket.h>
39 #include <linux/module.h>
40 #include <linux/sunrpc/msg_prot.h>
41 #include <linux/sunrpc/gss_asn1.h>
42 #include <linux/sunrpc/auth_gss.h>
43 #include <linux/sunrpc/svcauth_gss.h>
44 #include <linux/sunrpc/gss_err.h>
45 #include <linux/sunrpc/sched.h>
46 #include <linux/sunrpc/gss_api.h>
47 #include <linux/sunrpc/clnt.h>
48 
49 #ifdef RPC_DEBUG
50 # define RPCDBG_FACILITY        RPCDBG_AUTH
51 #endif
52 
53 static LIST_HEAD(registered_mechs);
54 static DEFINE_SPINLOCK(registered_mechs_lock);
55 
56 static void
57 gss_mech_free(struct gss_api_mech *gm)
58 {
59 	struct pf_desc *pf;
60 	int i;
61 
62 	for (i = 0; i < gm->gm_pf_num; i++) {
63 		pf = &gm->gm_pfs[i];
64 		if (pf->auth_domain_name)
65 			kfree(pf->auth_domain_name);
66 		pf->auth_domain_name = NULL;
67 	}
68 }
69 
70 static inline char *
71 make_auth_domain_name(char *name)
72 {
73 	static char	*prefix = "gss/";
74 	char		*new;
75 
76 	new = kmalloc(strlen(name) + strlen(prefix) + 1, GFP_KERNEL);
77 	if (new) {
78 		strcpy(new, prefix);
79 		strcat(new, name);
80 	}
81 	return new;
82 }
83 
84 static int
85 gss_mech_svc_setup(struct gss_api_mech *gm)
86 {
87 	struct pf_desc *pf;
88 	int i, status;
89 
90 	for (i = 0; i < gm->gm_pf_num; i++) {
91 		pf = &gm->gm_pfs[i];
92 		pf->auth_domain_name = make_auth_domain_name(pf->name);
93 		status = -ENOMEM;
94 		if (pf->auth_domain_name == NULL)
95 			goto out;
96 		status = svcauth_gss_register_pseudoflavor(pf->pseudoflavor,
97 							pf->auth_domain_name);
98 		if (status)
99 			goto out;
100 	}
101 	return 0;
102 out:
103 	gss_mech_free(gm);
104 	return status;
105 }
106 
107 int
108 gss_mech_register(struct gss_api_mech *gm)
109 {
110 	int status;
111 
112 	status = gss_mech_svc_setup(gm);
113 	if (status)
114 		return status;
115 	spin_lock(&registered_mechs_lock);
116 	list_add(&gm->gm_list, &registered_mechs);
117 	spin_unlock(&registered_mechs_lock);
118 	dprintk("RPC:      registered gss mechanism %s\n", gm->gm_name);
119 	return 0;
120 }
121 
122 EXPORT_SYMBOL(gss_mech_register);
123 
124 void
125 gss_mech_unregister(struct gss_api_mech *gm)
126 {
127 	spin_lock(&registered_mechs_lock);
128 	list_del(&gm->gm_list);
129 	spin_unlock(&registered_mechs_lock);
130 	dprintk("RPC:      unregistered gss mechanism %s\n", gm->gm_name);
131 	gss_mech_free(gm);
132 }
133 
134 EXPORT_SYMBOL(gss_mech_unregister);
135 
136 struct gss_api_mech *
137 gss_mech_get(struct gss_api_mech *gm)
138 {
139 	__module_get(gm->gm_owner);
140 	return gm;
141 }
142 
143 EXPORT_SYMBOL(gss_mech_get);
144 
145 struct gss_api_mech *
146 gss_mech_get_by_name(const char *name)
147 {
148 	struct gss_api_mech	*pos, *gm = NULL;
149 
150 	spin_lock(&registered_mechs_lock);
151 	list_for_each_entry(pos, &registered_mechs, gm_list) {
152 		if (0 == strcmp(name, pos->gm_name)) {
153 			if (try_module_get(pos->gm_owner))
154 				gm = pos;
155 			break;
156 		}
157 	}
158 	spin_unlock(&registered_mechs_lock);
159 	return gm;
160 
161 }
162 
163 EXPORT_SYMBOL(gss_mech_get_by_name);
164 
165 static inline int
166 mech_supports_pseudoflavor(struct gss_api_mech *gm, u32 pseudoflavor)
167 {
168 	int i;
169 
170 	for (i = 0; i < gm->gm_pf_num; i++) {
171 		if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
172 			return 1;
173 	}
174 	return 0;
175 }
176 
177 struct gss_api_mech *
178 gss_mech_get_by_pseudoflavor(u32 pseudoflavor)
179 {
180 	struct gss_api_mech *pos, *gm = NULL;
181 
182 	spin_lock(&registered_mechs_lock);
183 	list_for_each_entry(pos, &registered_mechs, gm_list) {
184 		if (!mech_supports_pseudoflavor(pos, pseudoflavor)) {
185 			module_put(pos->gm_owner);
186 			continue;
187 		}
188 		if (try_module_get(pos->gm_owner))
189 			gm = pos;
190 		break;
191 	}
192 	spin_unlock(&registered_mechs_lock);
193 	return gm;
194 }
195 
196 EXPORT_SYMBOL(gss_mech_get_by_pseudoflavor);
197 
198 u32
199 gss_pseudoflavor_to_service(struct gss_api_mech *gm, u32 pseudoflavor)
200 {
201 	int i;
202 
203 	for (i = 0; i < gm->gm_pf_num; i++) {
204 		if (gm->gm_pfs[i].pseudoflavor == pseudoflavor)
205 			return gm->gm_pfs[i].service;
206 	}
207 	return 0;
208 }
209 
210 EXPORT_SYMBOL(gss_pseudoflavor_to_service);
211 
212 char *
213 gss_service_to_auth_domain_name(struct gss_api_mech *gm, u32 service)
214 {
215 	int i;
216 
217 	for (i = 0; i < gm->gm_pf_num; i++) {
218 		if (gm->gm_pfs[i].service == service)
219 			return gm->gm_pfs[i].auth_domain_name;
220 	}
221 	return NULL;
222 }
223 
224 EXPORT_SYMBOL(gss_service_to_auth_domain_name);
225 
226 void
227 gss_mech_put(struct gss_api_mech * gm)
228 {
229 	module_put(gm->gm_owner);
230 }
231 
232 EXPORT_SYMBOL(gss_mech_put);
233 
234 /* The mech could probably be determined from the token instead, but it's just
235  * as easy for now to pass it in. */
236 int
237 gss_import_sec_context(const void *input_token, size_t bufsize,
238 		       struct gss_api_mech	*mech,
239 		       struct gss_ctx		**ctx_id)
240 {
241 	if (!(*ctx_id = kmalloc(sizeof(**ctx_id), GFP_KERNEL)))
242 		return GSS_S_FAILURE;
243 	memset(*ctx_id, 0, sizeof(**ctx_id));
244 	(*ctx_id)->mech_type = gss_mech_get(mech);
245 
246 	return mech->gm_ops
247 		->gss_import_sec_context(input_token, bufsize, *ctx_id);
248 }
249 
250 /* gss_get_mic: compute a mic over message and return mic_token. */
251 
252 u32
253 gss_get_mic(struct gss_ctx	*context_handle,
254 	    u32			qop,
255 	    struct xdr_buf	*message,
256 	    struct xdr_netobj	*mic_token)
257 {
258 	 return context_handle->mech_type->gm_ops
259 		->gss_get_mic(context_handle,
260 			      qop,
261 			      message,
262 			      mic_token);
263 }
264 
265 /* gss_verify_mic: check whether the provided mic_token verifies message. */
266 
267 u32
268 gss_verify_mic(struct gss_ctx		*context_handle,
269 	       struct xdr_buf		*message,
270 	       struct xdr_netobj	*mic_token,
271 	       u32			*qstate)
272 {
273 	return context_handle->mech_type->gm_ops
274 		->gss_verify_mic(context_handle,
275 				 message,
276 				 mic_token,
277 				 qstate);
278 }
279 
280 /* gss_delete_sec_context: free all resources associated with context_handle.
281  * Note this differs from the RFC 2744-specified prototype in that we don't
282  * bother returning an output token, since it would never be used anyway. */
283 
284 u32
285 gss_delete_sec_context(struct gss_ctx	**context_handle)
286 {
287 	dprintk("RPC:      gss_delete_sec_context deleting %p\n",
288 			*context_handle);
289 
290 	if (!*context_handle)
291 		return(GSS_S_NO_CONTEXT);
292 	if ((*context_handle)->internal_ctx_id != 0)
293 		(*context_handle)->mech_type->gm_ops
294 			->gss_delete_sec_context((*context_handle)
295 							->internal_ctx_id);
296 	if ((*context_handle)->mech_type)
297 		gss_mech_put((*context_handle)->mech_type);
298 	kfree(*context_handle);
299 	*context_handle=NULL;
300 	return GSS_S_COMPLETE;
301 }
302