Line data Source code
1 : /*
2 : Unix SMB/CIFS implementation.
3 : Authenticate against Samba4's auth subsystem
4 : Copyright (C) Volker Lendecke 2008
5 : Copyright (C) Andrew Bartlett 2010
6 :
7 : This program is free software; you can redistribute it and/or modify
8 : it under the terms of the GNU General Public License as published by
9 : the Free Software Foundation; either version 3 of the License, or
10 : (at your option) any later version.
11 :
12 : This program is distributed in the hope that it will be useful,
13 : but WITHOUT ANY WARRANTY; without even the implied warranty of
14 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 : GNU General Public License for more details.
16 :
17 : You should have received a copy of the GNU General Public License
18 : along with this program. If not, see <http://www.gnu.org/licenses/>.
19 : */
20 :
21 : #include "includes.h"
22 : #include "source3/include/auth.h"
23 : #include "source3/include/messages.h"
24 : #include "source4/auth/auth.h"
25 : #include "auth/auth_sam_reply.h"
26 : #include "param/param.h"
27 : #include "source4/lib/events/events.h"
28 : #include "source4/lib/messaging/messaging.h"
29 : #include "auth/gensec/gensec.h"
30 : #include "auth/credentials/credentials.h"
31 : #include "lib/global_contexts.h"
32 : #include "lib/util/idtree.h"
33 :
34 : #undef DBGC_CLASS
35 : #define DBGC_CLASS DBGC_AUTH
36 :
37 : static NTSTATUS make_auth4_context_s4(const struct auth_context *auth_context,
38 : TALLOC_CTX *mem_ctx,
39 : struct auth4_context **auth4_context);
40 :
41 : static struct idr_context *task_id_tree;
42 :
43 9948 : static int free_task_id(struct server_id *server_id)
44 : {
45 9948 : idr_remove(task_id_tree, server_id->task_id);
46 9948 : return 0;
47 : }
48 :
49 : /* Return a server_id with a unique task_id element. Free the
50 : * returned pointer to de-allocate the task_id via a talloc destructor
51 : * (ie, use talloc_free()) */
52 9948 : static struct server_id *new_server_id_task(TALLOC_CTX *mem_ctx)
53 : {
54 : struct messaging_context *msg_ctx;
55 : struct server_id *server_id;
56 : int task_id;
57 9948 : if (!task_id_tree) {
58 3713 : task_id_tree = idr_init(NULL);
59 3713 : if (!task_id_tree) {
60 0 : return NULL;
61 : }
62 : }
63 :
64 9948 : msg_ctx = global_messaging_context();
65 9948 : if (msg_ctx == NULL) {
66 0 : return NULL;
67 : }
68 :
69 9948 : server_id = talloc(mem_ctx, struct server_id);
70 :
71 9948 : if (!server_id) {
72 0 : return NULL;
73 : }
74 9948 : *server_id = messaging_server_id(msg_ctx);
75 :
76 : /* 0 is the default server_id, so we need to start with 1 */
77 9948 : task_id = idr_get_new_above(task_id_tree, server_id, 1, INT32_MAX);
78 :
79 9948 : if (task_id == -1) {
80 0 : talloc_free(server_id);
81 0 : return NULL;
82 : }
83 :
84 9948 : talloc_set_destructor(server_id, free_task_id);
85 9948 : server_id->task_id = task_id;
86 9948 : return server_id;
87 : }
88 :
89 : /*
90 : * This module is not an ordinary authentication module. It is really
91 : * a way to redirect the whole authentication and authorization stack
92 : * to use the source4 auth code, not a way to just handle NTLM
93 : * authentication.
94 : *
95 : * See the comments above each function for how that hook changes the
96 : * behaviour.
97 : */
98 :
99 : /*
100 : * This hook is currently used by winbindd only, as all other NTLM
101 : * logins go via the hooks provided by make_auth4_context_s4() below.
102 : *
103 : * This is only left in case we find a way that it might become useful
104 : * in future. Importantly, this routine returns the information
105 : * needed for a NETLOGON SamLogon, not what is needed to establish a
106 : * session.
107 : *
108 : * We expect we may use this hook in the source3/ winbind when this
109 : * services the AD DC. It is tested via pdbtest.
110 : */
111 :
112 1 : static NTSTATUS check_samba4_security(
113 : const struct auth_context *auth_context,
114 : void *my_private_data,
115 : TALLOC_CTX *mem_ctx,
116 : const struct auth_usersupplied_info *user_info,
117 : struct auth_serversupplied_info **pserver_info)
118 : {
119 1 : TALLOC_CTX *frame = talloc_stackframe();
120 1 : struct netr_SamInfo3 *info3 = NULL;
121 : NTSTATUS nt_status;
122 : struct auth_user_info_dc *user_info_dc;
123 : struct auth4_context *auth4_context;
124 1 : uint8_t authoritative = 1;
125 1 : struct auth_serversupplied_info *server_info = NULL;
126 :
127 1 : nt_status = make_auth4_context_s4(auth_context, mem_ctx, &auth4_context);
128 1 : if (!NT_STATUS_IS_OK(nt_status)) {
129 0 : TALLOC_FREE(frame);
130 0 : goto done;
131 : }
132 :
133 1 : nt_status = auth_context_set_challenge(auth4_context, auth_context->challenge.data, "auth_samba4");
134 1 : if (!NT_STATUS_IS_OK(nt_status)) {
135 0 : TALLOC_FREE(auth4_context);
136 0 : TALLOC_FREE(frame);
137 0 : return nt_status;
138 : }
139 :
140 1 : nt_status = auth_check_password(auth4_context, auth4_context, user_info,
141 : &user_info_dc, &authoritative);
142 1 : if (!NT_STATUS_IS_OK(nt_status)) {
143 0 : if (NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_SUCH_USER) &&
144 0 : authoritative == 0)
145 : {
146 0 : nt_status = NT_STATUS_NOT_IMPLEMENTED;
147 : }
148 0 : TALLOC_FREE(auth4_context);
149 0 : TALLOC_FREE(frame);
150 0 : return nt_status;
151 : }
152 :
153 1 : nt_status = auth_convert_user_info_dc_saminfo3(mem_ctx,
154 : user_info_dc,
155 : &info3);
156 1 : if (NT_STATUS_IS_OK(nt_status)) {
157 : /* We need the strings from the server_info to be valid as long as the info3 is around */
158 1 : talloc_steal(info3, user_info_dc);
159 : }
160 1 : talloc_free(auth4_context);
161 :
162 1 : if (!NT_STATUS_IS_OK(nt_status)) {
163 0 : goto done;
164 : }
165 :
166 1 : if (user_info->flags & USER_INFO_INFO3_AND_NO_AUTHZ) {
167 0 : server_info = make_server_info(mem_ctx);
168 0 : if (server_info == NULL) {
169 0 : nt_status = NT_STATUS_NO_MEMORY;
170 0 : goto done;
171 : }
172 0 : server_info->info3 = talloc_move(server_info, &info3);
173 : } else {
174 1 : nt_status = make_server_info_info3(
175 : mem_ctx,
176 1 : user_info->client.account_name,
177 1 : user_info->mapped.domain_name,
178 : &server_info,
179 : info3);
180 1 : if (!NT_STATUS_IS_OK(nt_status)) {
181 0 : DEBUG(10, ("make_server_info_info3 failed: %s\n",
182 : nt_errstr(nt_status)));
183 0 : goto done;
184 : }
185 : }
186 :
187 1 : *pserver_info = server_info;
188 1 : nt_status = NT_STATUS_OK;
189 :
190 1 : done:
191 1 : TALLOC_FREE(frame);
192 1 : return nt_status;
193 : }
194 :
195 : /*
196 : * Hook to allow the source4 set of GENSEC modules to handle
197 : * blob-based authentication mechanisms, without directly linking the
198 : * mechanism code.
199 : *
200 : * This may eventually go away, when the GSSAPI acceptors are merged,
201 : * when we will just rely on the make_auth4_context_s4 hook instead.
202 : *
203 : * Even for NTLMSSP, which has a common module, significant parts of
204 : * the behaviour are overridden here, because it uses the source4 NTLM
205 : * stack and the source4 mapping between the PAC/SamLogon response and
206 : * the local token.
207 : *
208 : * It is important to override all this to ensure that the exact same
209 : * token is generated and used in the SMB and LDAP servers, for NTLM
210 : * and for Kerberos.
211 : */
212 9924 : static NTSTATUS prepare_gensec(const struct auth_context *auth_context,
213 : TALLOC_CTX *mem_ctx,
214 : struct gensec_security **gensec_context)
215 : {
216 : NTSTATUS status;
217 : struct loadparm_context *lp_ctx;
218 : struct tevent_context *event_ctx;
219 9924 : TALLOC_CTX *frame = talloc_stackframe();
220 : struct gensec_security *gensec_ctx;
221 : struct imessaging_context *msg_ctx;
222 : struct cli_credentials *server_credentials;
223 : struct server_id *server_id;
224 :
225 9924 : lp_ctx = loadparm_init_s3(frame, loadparm_s3_helpers());
226 9924 : if (lp_ctx == NULL) {
227 0 : DEBUG(1, ("loadparm_init_s3 failed\n"));
228 0 : TALLOC_FREE(frame);
229 0 : return NT_STATUS_INVALID_SERVER_STATE;
230 : }
231 9924 : event_ctx = s4_event_context_init(frame);
232 9924 : if (event_ctx == NULL) {
233 0 : DEBUG(1, ("s4_event_context_init failed\n"));
234 0 : TALLOC_FREE(frame);
235 0 : return NT_STATUS_INVALID_SERVER_STATE;
236 : }
237 :
238 9924 : server_id = new_server_id_task(frame);
239 9924 : if (server_id == NULL) {
240 0 : DEBUG(1, ("new_server_id_task failed\n"));
241 0 : TALLOC_FREE(frame);
242 0 : return NT_STATUS_INVALID_SERVER_STATE;
243 : }
244 :
245 9924 : msg_ctx = imessaging_init_discard_incoming(frame,
246 : lp_ctx,
247 : *server_id,
248 : event_ctx);
249 9924 : if (msg_ctx == NULL) {
250 0 : DEBUG(1, ("imessaging_init_discard_incoming failed\n"));
251 0 : TALLOC_FREE(frame);
252 0 : return NT_STATUS_INVALID_SERVER_STATE;
253 : }
254 :
255 9924 : talloc_reparent(frame, msg_ctx, server_id);
256 :
257 : server_credentials
258 9924 : = cli_credentials_init_server(frame, lp_ctx);
259 9924 : if (!server_credentials) {
260 0 : DEBUG(1, ("Failed to init server credentials"));
261 0 : TALLOC_FREE(frame);
262 0 : return NT_STATUS_INVALID_SERVER_STATE;
263 : }
264 :
265 9924 : status = samba_server_gensec_start(mem_ctx,
266 : event_ctx, msg_ctx,
267 : lp_ctx, server_credentials, "cifs",
268 : &gensec_ctx);
269 9924 : if (!NT_STATUS_IS_OK(status)) {
270 0 : DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
271 0 : TALLOC_FREE(frame);
272 0 : return status;
273 : }
274 :
275 9924 : talloc_reparent(frame, gensec_ctx, msg_ctx);
276 9924 : talloc_reparent(frame, gensec_ctx, event_ctx);
277 9924 : talloc_reparent(frame, gensec_ctx, lp_ctx);
278 9924 : talloc_reparent(frame, gensec_ctx, server_credentials);
279 :
280 9924 : gensec_want_feature(gensec_ctx, GENSEC_FEATURE_SESSION_KEY);
281 9924 : gensec_want_feature(gensec_ctx, GENSEC_FEATURE_UNIX_TOKEN);
282 :
283 9924 : *gensec_context = gensec_ctx;
284 9924 : TALLOC_FREE(frame);
285 9924 : return status;
286 : }
287 :
288 : /*
289 : * Hook to allow handling of NTLM authentication for AD operation
290 : * without directly linking the s4 auth stack
291 : *
292 : * This ensures we use the source4 authentication stack, as well as
293 : * the authorization stack to create the user's token. This ensures
294 : * consistency between NTLM logins and NTLMSSP logins, as NTLMSSP is
295 : * handled by the hook above.
296 : */
297 24 : static NTSTATUS make_auth4_context_s4(const struct auth_context *auth_context,
298 : TALLOC_CTX *mem_ctx,
299 : struct auth4_context **auth4_context)
300 : {
301 : NTSTATUS status;
302 : struct loadparm_context *lp_ctx;
303 : struct tevent_context *event_ctx;
304 24 : TALLOC_CTX *frame = talloc_stackframe();
305 : struct imessaging_context *msg_ctx;
306 : struct server_id *server_id;
307 :
308 24 : lp_ctx = loadparm_init_s3(frame, loadparm_s3_helpers());
309 24 : if (lp_ctx == NULL) {
310 0 : DEBUG(1, ("loadparm_init_s3 failed\n"));
311 0 : TALLOC_FREE(frame);
312 0 : return NT_STATUS_INVALID_SERVER_STATE;
313 : }
314 24 : event_ctx = s4_event_context_init(frame);
315 24 : if (event_ctx == NULL) {
316 0 : DEBUG(1, ("s4_event_context_init failed\n"));
317 0 : TALLOC_FREE(frame);
318 0 : return NT_STATUS_INVALID_SERVER_STATE;
319 : }
320 :
321 24 : server_id = new_server_id_task(frame);
322 24 : if (server_id == NULL) {
323 0 : DEBUG(1, ("new_server_id_task failed\n"));
324 0 : TALLOC_FREE(frame);
325 0 : return NT_STATUS_INVALID_SERVER_STATE;
326 : }
327 :
328 24 : msg_ctx = imessaging_init_discard_incoming(frame,
329 : lp_ctx,
330 : *server_id,
331 : event_ctx);
332 24 : if (msg_ctx == NULL) {
333 0 : DEBUG(1, ("imessaging_init_discard_incoming failed\n"));
334 0 : TALLOC_FREE(frame);
335 0 : return NT_STATUS_INVALID_SERVER_STATE;
336 : }
337 24 : talloc_reparent(frame, msg_ctx, server_id);
338 :
339 : /* Allow forcing a specific auth4 module */
340 24 : if (!auth_context->forced_samba4_methods) {
341 24 : status = auth_context_create(mem_ctx,
342 : event_ctx,
343 : msg_ctx,
344 : lp_ctx,
345 : auth4_context);
346 : } else {
347 0 : const char * const *forced_auth_methods = (const char * const *)str_list_make(mem_ctx, auth_context->forced_samba4_methods, NULL);
348 0 : status = auth_context_create_methods(mem_ctx, forced_auth_methods, event_ctx, msg_ctx, lp_ctx, NULL, auth4_context);
349 : }
350 24 : if (!NT_STATUS_IS_OK(status)) {
351 0 : DEBUG(1, ("Failed to start auth server code: %s\n", nt_errstr(status)));
352 0 : TALLOC_FREE(frame);
353 0 : return status;
354 : }
355 :
356 24 : talloc_reparent(frame, *auth4_context, msg_ctx);
357 24 : talloc_reparent(frame, *auth4_context, event_ctx);
358 24 : talloc_reparent(frame, *auth4_context, lp_ctx);
359 :
360 24 : TALLOC_FREE(frame);
361 24 : return status;
362 : }
363 :
364 : /* module initialisation */
365 9948 : static NTSTATUS auth_init_samba4(struct auth_context *auth_context,
366 : const char *param,
367 : struct auth_methods **auth_method)
368 : {
369 : struct auth_methods *result;
370 :
371 9948 : gensec_init();
372 :
373 9948 : result = talloc_zero(auth_context, struct auth_methods);
374 9948 : if (result == NULL) {
375 0 : return NT_STATUS_NO_MEMORY;
376 : }
377 9948 : result->name = "samba4";
378 9948 : result->auth = check_samba4_security;
379 9948 : result->prepare_gensec = prepare_gensec;
380 9948 : result->make_auth4_context = make_auth4_context_s4;
381 :
382 9948 : if (param && *param) {
383 0 : auth_context->forced_samba4_methods = talloc_strdup(result, param);
384 0 : if (!auth_context->forced_samba4_methods) {
385 0 : return NT_STATUS_NO_MEMORY;
386 : }
387 : }
388 :
389 9948 : *auth_method = result;
390 9948 : return NT_STATUS_OK;
391 : }
392 :
393 : NTSTATUS auth_samba4_init(TALLOC_CTX *mem_ctx);
394 5093 : NTSTATUS auth_samba4_init(TALLOC_CTX *mem_ctx)
395 : {
396 5093 : smb_register_auth(AUTH_INTERFACE_VERSION, "samba4",
397 : auth_init_samba4);
398 5093 : return NT_STATUS_OK;
399 : }
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