Pull misc into release branch
[sfrench/cifs-2.6.git] / net / netlabel / netlabel_cipso_v4.c
1 /*
2  * NetLabel CIPSO/IPv4 Support
3  *
4  * This file defines the CIPSO/IPv4 functions for the NetLabel system.  The
5  * NetLabel system manages static and dynamic label mappings for network
6  * protocols such as CIPSO and RIPSO.
7  *
8  * Author: Paul Moore <paul.moore@hp.com>
9  *
10  */
11
12 /*
13  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
14  *
15  * This program is free software;  you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or
18  * (at your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful,
21  * but WITHOUT ANY WARRANTY;  without even the implied warranty of
22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
23  * the GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program;  if not, write to the Free Software
27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28  *
29  */
30
31 #include <linux/types.h>
32 #include <linux/socket.h>
33 #include <linux/string.h>
34 #include <linux/skbuff.h>
35 #include <linux/audit.h>
36 #include <net/sock.h>
37 #include <net/netlink.h>
38 #include <net/genetlink.h>
39 #include <net/netlabel.h>
40 #include <net/cipso_ipv4.h>
41
42 #include "netlabel_user.h"
43 #include "netlabel_cipso_v4.h"
44 #include "netlabel_mgmt.h"
45
46 /* Argument struct for cipso_v4_doi_walk() */
47 struct netlbl_cipsov4_doiwalk_arg {
48         struct netlink_callback *nl_cb;
49         struct sk_buff *skb;
50         u32 seq;
51 };
52
53 /* NetLabel Generic NETLINK CIPSOv4 family */
54 static struct genl_family netlbl_cipsov4_gnl_family = {
55         .id = GENL_ID_GENERATE,
56         .hdrsize = 0,
57         .name = NETLBL_NLTYPE_CIPSOV4_NAME,
58         .version = NETLBL_PROTO_VERSION,
59         .maxattr = NLBL_CIPSOV4_A_MAX,
60 };
61
62 /* NetLabel Netlink attribute policy */
63 static const struct nla_policy netlbl_cipsov4_genl_policy[NLBL_CIPSOV4_A_MAX + 1] = {
64         [NLBL_CIPSOV4_A_DOI] = { .type = NLA_U32 },
65         [NLBL_CIPSOV4_A_MTYPE] = { .type = NLA_U32 },
66         [NLBL_CIPSOV4_A_TAG] = { .type = NLA_U8 },
67         [NLBL_CIPSOV4_A_TAGLST] = { .type = NLA_NESTED },
68         [NLBL_CIPSOV4_A_MLSLVLLOC] = { .type = NLA_U32 },
69         [NLBL_CIPSOV4_A_MLSLVLREM] = { .type = NLA_U32 },
70         [NLBL_CIPSOV4_A_MLSLVL] = { .type = NLA_NESTED },
71         [NLBL_CIPSOV4_A_MLSLVLLST] = { .type = NLA_NESTED },
72         [NLBL_CIPSOV4_A_MLSCATLOC] = { .type = NLA_U32 },
73         [NLBL_CIPSOV4_A_MLSCATREM] = { .type = NLA_U32 },
74         [NLBL_CIPSOV4_A_MLSCAT] = { .type = NLA_NESTED },
75         [NLBL_CIPSOV4_A_MLSCATLST] = { .type = NLA_NESTED },
76 };
77
78 /*
79  * Helper Functions
80  */
81
82 /**
83  * netlbl_cipsov4_doi_free - Frees a CIPSO V4 DOI definition
84  * @entry: the entry's RCU field
85  *
86  * Description:
87  * This function is designed to be used as a callback to the call_rcu()
88  * function so that the memory allocated to the DOI definition can be released
89  * safely.
90  *
91  */
92 static void netlbl_cipsov4_doi_free(struct rcu_head *entry)
93 {
94         struct cipso_v4_doi *ptr;
95
96         ptr = container_of(entry, struct cipso_v4_doi, rcu);
97         switch (ptr->type) {
98         case CIPSO_V4_MAP_STD:
99                 kfree(ptr->map.std->lvl.cipso);
100                 kfree(ptr->map.std->lvl.local);
101                 kfree(ptr->map.std->cat.cipso);
102                 kfree(ptr->map.std->cat.local);
103                 break;
104         }
105         kfree(ptr);
106 }
107
108 /**
109  * netlbl_cipsov4_add_common - Parse the common sections of a ADD message
110  * @info: the Generic NETLINK info block
111  * @doi_def: the CIPSO V4 DOI definition
112  *
113  * Description:
114  * Parse the common sections of a ADD message and fill in the related values
115  * in @doi_def.  Returns zero on success, negative values on failure.
116  *
117  */
118 static int netlbl_cipsov4_add_common(struct genl_info *info,
119                                      struct cipso_v4_doi *doi_def)
120 {
121         struct nlattr *nla;
122         int nla_rem;
123         u32 iter = 0;
124
125         doi_def->doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
126
127         if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_TAGLST],
128                                 NLBL_CIPSOV4_A_MAX,
129                                 netlbl_cipsov4_genl_policy) != 0)
130                 return -EINVAL;
131
132         nla_for_each_nested(nla, info->attrs[NLBL_CIPSOV4_A_TAGLST], nla_rem)
133                 if (nla->nla_type == NLBL_CIPSOV4_A_TAG) {
134                         if (iter >= CIPSO_V4_TAG_MAXCNT)
135                                 return -EINVAL;
136                         doi_def->tags[iter++] = nla_get_u8(nla);
137                 }
138         while (iter < CIPSO_V4_TAG_MAXCNT)
139                 doi_def->tags[iter++] = CIPSO_V4_TAG_INVALID;
140
141         return 0;
142 }
143
144 /*
145  * NetLabel Command Handlers
146  */
147
148 /**
149  * netlbl_cipsov4_add_std - Adds a CIPSO V4 DOI definition
150  * @info: the Generic NETLINK info block
151  *
152  * Description:
153  * Create a new CIPSO_V4_MAP_STD DOI definition based on the given ADD message
154  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
155  * error.
156  *
157  */
158 static int netlbl_cipsov4_add_std(struct genl_info *info)
159 {
160         int ret_val = -EINVAL;
161         struct cipso_v4_doi *doi_def = NULL;
162         struct nlattr *nla_a;
163         struct nlattr *nla_b;
164         int nla_a_rem;
165         int nla_b_rem;
166         u32 iter;
167
168         if (!info->attrs[NLBL_CIPSOV4_A_TAGLST] ||
169             !info->attrs[NLBL_CIPSOV4_A_MLSLVLLST])
170                 return -EINVAL;
171
172         if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
173                                 NLBL_CIPSOV4_A_MAX,
174                                 netlbl_cipsov4_genl_policy) != 0)
175                 return -EINVAL;
176
177         doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
178         if (doi_def == NULL)
179                 return -ENOMEM;
180         doi_def->map.std = kzalloc(sizeof(*doi_def->map.std), GFP_KERNEL);
181         if (doi_def->map.std == NULL) {
182                 ret_val = -ENOMEM;
183                 goto add_std_failure;
184         }
185         doi_def->type = CIPSO_V4_MAP_STD;
186
187         ret_val = netlbl_cipsov4_add_common(info, doi_def);
188         if (ret_val != 0)
189                 goto add_std_failure;
190         ret_val = -EINVAL;
191
192         nla_for_each_nested(nla_a,
193                             info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
194                             nla_a_rem)
195                 if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
196                         if (nla_validate_nested(nla_a,
197                                             NLBL_CIPSOV4_A_MAX,
198                                             netlbl_cipsov4_genl_policy) != 0)
199                                         goto add_std_failure;
200                         nla_for_each_nested(nla_b, nla_a, nla_b_rem)
201                                 switch (nla_b->nla_type) {
202                                 case NLBL_CIPSOV4_A_MLSLVLLOC:
203                                         if (nla_get_u32(nla_b) >
204                                             CIPSO_V4_MAX_LOC_LVLS)
205                                                 goto add_std_failure;
206                                         if (nla_get_u32(nla_b) >=
207                                             doi_def->map.std->lvl.local_size)
208                                              doi_def->map.std->lvl.local_size =
209                                                      nla_get_u32(nla_b) + 1;
210                                         break;
211                                 case NLBL_CIPSOV4_A_MLSLVLREM:
212                                         if (nla_get_u32(nla_b) >
213                                             CIPSO_V4_MAX_REM_LVLS)
214                                                 goto add_std_failure;
215                                         if (nla_get_u32(nla_b) >=
216                                             doi_def->map.std->lvl.cipso_size)
217                                              doi_def->map.std->lvl.cipso_size =
218                                                      nla_get_u32(nla_b) + 1;
219                                         break;
220                                 }
221                 }
222         doi_def->map.std->lvl.local = kcalloc(doi_def->map.std->lvl.local_size,
223                                               sizeof(u32),
224                                               GFP_KERNEL);
225         if (doi_def->map.std->lvl.local == NULL) {
226                 ret_val = -ENOMEM;
227                 goto add_std_failure;
228         }
229         doi_def->map.std->lvl.cipso = kcalloc(doi_def->map.std->lvl.cipso_size,
230                                               sizeof(u32),
231                                               GFP_KERNEL);
232         if (doi_def->map.std->lvl.cipso == NULL) {
233                 ret_val = -ENOMEM;
234                 goto add_std_failure;
235         }
236         for (iter = 0; iter < doi_def->map.std->lvl.local_size; iter++)
237                 doi_def->map.std->lvl.local[iter] = CIPSO_V4_INV_LVL;
238         for (iter = 0; iter < doi_def->map.std->lvl.cipso_size; iter++)
239                 doi_def->map.std->lvl.cipso[iter] = CIPSO_V4_INV_LVL;
240         nla_for_each_nested(nla_a,
241                             info->attrs[NLBL_CIPSOV4_A_MLSLVLLST],
242                             nla_a_rem)
243                 if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSLVL) {
244                         struct nlattr *lvl_loc;
245                         struct nlattr *lvl_rem;
246
247                         lvl_loc = nla_find_nested(nla_a,
248                                                   NLBL_CIPSOV4_A_MLSLVLLOC);
249                         lvl_rem = nla_find_nested(nla_a,
250                                                   NLBL_CIPSOV4_A_MLSLVLREM);
251                         if (lvl_loc == NULL || lvl_rem == NULL)
252                                 goto add_std_failure;
253                         doi_def->map.std->lvl.local[nla_get_u32(lvl_loc)] =
254                                 nla_get_u32(lvl_rem);
255                         doi_def->map.std->lvl.cipso[nla_get_u32(lvl_rem)] =
256                                 nla_get_u32(lvl_loc);
257                 }
258
259         if (info->attrs[NLBL_CIPSOV4_A_MLSCATLST]) {
260                 if (nla_validate_nested(info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
261                                         NLBL_CIPSOV4_A_MAX,
262                                         netlbl_cipsov4_genl_policy) != 0)
263                         goto add_std_failure;
264
265                 nla_for_each_nested(nla_a,
266                                     info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
267                                     nla_a_rem)
268                         if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
269                                 if (nla_validate_nested(nla_a,
270                                               NLBL_CIPSOV4_A_MAX,
271                                               netlbl_cipsov4_genl_policy) != 0)
272                                         goto add_std_failure;
273                                 nla_for_each_nested(nla_b, nla_a, nla_b_rem)
274                                         switch (nla_b->nla_type) {
275                                         case NLBL_CIPSOV4_A_MLSCATLOC:
276                                                 if (nla_get_u32(nla_b) >
277                                                     CIPSO_V4_MAX_LOC_CATS)
278                                                         goto add_std_failure;
279                                                 if (nla_get_u32(nla_b) >=
280                                               doi_def->map.std->cat.local_size)
281                                              doi_def->map.std->cat.local_size =
282                                                      nla_get_u32(nla_b) + 1;
283                                                 break;
284                                         case NLBL_CIPSOV4_A_MLSCATREM:
285                                                 if (nla_get_u32(nla_b) >
286                                                     CIPSO_V4_MAX_REM_CATS)
287                                                         goto add_std_failure;
288                                                 if (nla_get_u32(nla_b) >=
289                                               doi_def->map.std->cat.cipso_size)
290                                              doi_def->map.std->cat.cipso_size =
291                                                      nla_get_u32(nla_b) + 1;
292                                                 break;
293                                         }
294                         }
295                 doi_def->map.std->cat.local = kcalloc(
296                                               doi_def->map.std->cat.local_size,
297                                               sizeof(u32),
298                                               GFP_KERNEL);
299                 if (doi_def->map.std->cat.local == NULL) {
300                         ret_val = -ENOMEM;
301                         goto add_std_failure;
302                 }
303                 doi_def->map.std->cat.cipso = kcalloc(
304                                               doi_def->map.std->cat.cipso_size,
305                                               sizeof(u32),
306                                               GFP_KERNEL);
307                 if (doi_def->map.std->cat.cipso == NULL) {
308                         ret_val = -ENOMEM;
309                         goto add_std_failure;
310                 }
311                 for (iter = 0; iter < doi_def->map.std->cat.local_size; iter++)
312                         doi_def->map.std->cat.local[iter] = CIPSO_V4_INV_CAT;
313                 for (iter = 0; iter < doi_def->map.std->cat.cipso_size; iter++)
314                         doi_def->map.std->cat.cipso[iter] = CIPSO_V4_INV_CAT;
315                 nla_for_each_nested(nla_a,
316                                     info->attrs[NLBL_CIPSOV4_A_MLSCATLST],
317                                     nla_a_rem)
318                         if (nla_a->nla_type == NLBL_CIPSOV4_A_MLSCAT) {
319                                 struct nlattr *cat_loc;
320                                 struct nlattr *cat_rem;
321
322                                 cat_loc = nla_find_nested(nla_a,
323                                                      NLBL_CIPSOV4_A_MLSCATLOC);
324                                 cat_rem = nla_find_nested(nla_a,
325                                                      NLBL_CIPSOV4_A_MLSCATREM);
326                                 if (cat_loc == NULL || cat_rem == NULL)
327                                         goto add_std_failure;
328                                 doi_def->map.std->cat.local[
329                                                         nla_get_u32(cat_loc)] =
330                                         nla_get_u32(cat_rem);
331                                 doi_def->map.std->cat.cipso[
332                                                         nla_get_u32(cat_rem)] =
333                                         nla_get_u32(cat_loc);
334                         }
335         }
336
337         ret_val = cipso_v4_doi_add(doi_def);
338         if (ret_val != 0)
339                 goto add_std_failure;
340         return 0;
341
342 add_std_failure:
343         if (doi_def)
344                 netlbl_cipsov4_doi_free(&doi_def->rcu);
345         return ret_val;
346 }
347
348 /**
349  * netlbl_cipsov4_add_pass - Adds a CIPSO V4 DOI definition
350  * @info: the Generic NETLINK info block
351  *
352  * Description:
353  * Create a new CIPSO_V4_MAP_PASS DOI definition based on the given ADD message
354  * and add it to the CIPSO V4 engine.  Return zero on success and non-zero on
355  * error.
356  *
357  */
358 static int netlbl_cipsov4_add_pass(struct genl_info *info)
359 {
360         int ret_val;
361         struct cipso_v4_doi *doi_def = NULL;
362
363         if (!info->attrs[NLBL_CIPSOV4_A_TAGLST])
364                 return -EINVAL;
365
366         doi_def = kmalloc(sizeof(*doi_def), GFP_KERNEL);
367         if (doi_def == NULL)
368                 return -ENOMEM;
369         doi_def->type = CIPSO_V4_MAP_PASS;
370
371         ret_val = netlbl_cipsov4_add_common(info, doi_def);
372         if (ret_val != 0)
373                 goto add_pass_failure;
374
375         ret_val = cipso_v4_doi_add(doi_def);
376         if (ret_val != 0)
377                 goto add_pass_failure;
378         return 0;
379
380 add_pass_failure:
381         netlbl_cipsov4_doi_free(&doi_def->rcu);
382         return ret_val;
383 }
384
385 /**
386  * netlbl_cipsov4_add - Handle an ADD message
387  * @skb: the NETLINK buffer
388  * @info: the Generic NETLINK info block
389  *
390  * Description:
391  * Create a new DOI definition based on the given ADD message and add it to the
392  * CIPSO V4 engine.  Returns zero on success, negative values on failure.
393  *
394  */
395 static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
396
397 {
398         int ret_val = -EINVAL;
399         u32 type;
400         u32 doi;
401         const char *type_str = "(unknown)";
402         struct audit_buffer *audit_buf;
403         struct netlbl_audit audit_info;
404
405         if (!info->attrs[NLBL_CIPSOV4_A_DOI] ||
406             !info->attrs[NLBL_CIPSOV4_A_MTYPE])
407                 return -EINVAL;
408
409         doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
410         netlbl_netlink_auditinfo(skb, &audit_info);
411
412         type = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_MTYPE]);
413         switch (type) {
414         case CIPSO_V4_MAP_STD:
415                 type_str = "std";
416                 ret_val = netlbl_cipsov4_add_std(info);
417                 break;
418         case CIPSO_V4_MAP_PASS:
419                 type_str = "pass";
420                 ret_val = netlbl_cipsov4_add_pass(info);
421                 break;
422         }
423         if (ret_val == 0)
424                 netlbl_mgmt_protocount_inc();
425
426         audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD,
427                                               &audit_info);
428         if (audit_buf != NULL) {
429                 audit_log_format(audit_buf,
430                                  " cipso_doi=%u cipso_type=%s res=%u",
431                                  doi,
432                                  type_str,
433                                  ret_val == 0 ? 1 : 0);
434                 audit_log_end(audit_buf);
435         }
436
437         return ret_val;
438 }
439
440 /**
441  * netlbl_cipsov4_list - Handle a LIST message
442  * @skb: the NETLINK buffer
443  * @info: the Generic NETLINK info block
444  *
445  * Description:
446  * Process a user generated LIST message and respond accordingly.  While the
447  * response message generated by the kernel is straightforward, determining
448  * before hand the size of the buffer to allocate is not (we have to generate
449  * the message to know the size).  In order to keep this function sane what we
450  * do is allocate a buffer of NLMSG_GOODSIZE and try to fit the response in
451  * that size, if we fail then we restart with a larger buffer and try again.
452  * We continue in this manner until we hit a limit of failed attempts then we
453  * give up and just send an error message.  Returns zero on success and
454  * negative values on error.
455  *
456  */
457 static int netlbl_cipsov4_list(struct sk_buff *skb, struct genl_info *info)
458 {
459         int ret_val;
460         struct sk_buff *ans_skb = NULL;
461         u32 nlsze_mult = 1;
462         void *data;
463         u32 doi;
464         struct nlattr *nla_a;
465         struct nlattr *nla_b;
466         struct cipso_v4_doi *doi_def;
467         u32 iter;
468
469         if (!info->attrs[NLBL_CIPSOV4_A_DOI]) {
470                 ret_val = -EINVAL;
471                 goto list_failure;
472         }
473
474 list_start:
475         ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE * nlsze_mult, GFP_KERNEL);
476         if (ans_skb == NULL) {
477                 ret_val = -ENOMEM;
478                 goto list_failure;
479         }
480         data = genlmsg_put_reply(ans_skb, info, &netlbl_cipsov4_gnl_family,
481                                  0, NLBL_CIPSOV4_C_LIST);
482         if (data == NULL) {
483                 ret_val = -ENOMEM;
484                 goto list_failure;
485         }
486
487         doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
488
489         rcu_read_lock();
490         doi_def = cipso_v4_doi_getdef(doi);
491         if (doi_def == NULL) {
492                 ret_val = -EINVAL;
493                 goto list_failure;
494         }
495
496         ret_val = nla_put_u32(ans_skb, NLBL_CIPSOV4_A_MTYPE, doi_def->type);
497         if (ret_val != 0)
498                 goto list_failure_lock;
499
500         nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_TAGLST);
501         if (nla_a == NULL) {
502                 ret_val = -ENOMEM;
503                 goto list_failure_lock;
504         }
505         for (iter = 0;
506              iter < CIPSO_V4_TAG_MAXCNT &&
507                doi_def->tags[iter] != CIPSO_V4_TAG_INVALID;
508              iter++) {
509                 ret_val = nla_put_u8(ans_skb,
510                                      NLBL_CIPSOV4_A_TAG,
511                                      doi_def->tags[iter]);
512                 if (ret_val != 0)
513                         goto list_failure_lock;
514         }
515         nla_nest_end(ans_skb, nla_a);
516
517         switch (doi_def->type) {
518         case CIPSO_V4_MAP_STD:
519                 nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVLLST);
520                 if (nla_a == NULL) {
521                         ret_val = -ENOMEM;
522                         goto list_failure_lock;
523                 }
524                 for (iter = 0;
525                      iter < doi_def->map.std->lvl.local_size;
526                      iter++) {
527                         if (doi_def->map.std->lvl.local[iter] ==
528                             CIPSO_V4_INV_LVL)
529                                 continue;
530
531                         nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSLVL);
532                         if (nla_b == NULL) {
533                                 ret_val = -ENOMEM;
534                                 goto list_retry;
535                         }
536                         ret_val = nla_put_u32(ans_skb,
537                                               NLBL_CIPSOV4_A_MLSLVLLOC,
538                                               iter);
539                         if (ret_val != 0)
540                                 goto list_retry;
541                         ret_val = nla_put_u32(ans_skb,
542                                             NLBL_CIPSOV4_A_MLSLVLREM,
543                                             doi_def->map.std->lvl.local[iter]);
544                         if (ret_val != 0)
545                                 goto list_retry;
546                         nla_nest_end(ans_skb, nla_b);
547                 }
548                 nla_nest_end(ans_skb, nla_a);
549
550                 nla_a = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCATLST);
551                 if (nla_a == NULL) {
552                         ret_val = -ENOMEM;
553                         goto list_retry;
554                 }
555                 for (iter = 0;
556                      iter < doi_def->map.std->cat.local_size;
557                      iter++) {
558                         if (doi_def->map.std->cat.local[iter] ==
559                             CIPSO_V4_INV_CAT)
560                                 continue;
561
562                         nla_b = nla_nest_start(ans_skb, NLBL_CIPSOV4_A_MLSCAT);
563                         if (nla_b == NULL) {
564                                 ret_val = -ENOMEM;
565                                 goto list_retry;
566                         }
567                         ret_val = nla_put_u32(ans_skb,
568                                               NLBL_CIPSOV4_A_MLSCATLOC,
569                                               iter);
570                         if (ret_val != 0)
571                                 goto list_retry;
572                         ret_val = nla_put_u32(ans_skb,
573                                             NLBL_CIPSOV4_A_MLSCATREM,
574                                             doi_def->map.std->cat.local[iter]);
575                         if (ret_val != 0)
576                                 goto list_retry;
577                         nla_nest_end(ans_skb, nla_b);
578                 }
579                 nla_nest_end(ans_skb, nla_a);
580
581                 break;
582         }
583         rcu_read_unlock();
584
585         genlmsg_end(ans_skb, data);
586
587         ret_val = genlmsg_reply(ans_skb, info);
588         if (ret_val != 0)
589                 goto list_failure;
590
591         return 0;
592
593 list_retry:
594         /* XXX - this limit is a guesstimate */
595         if (nlsze_mult < 4) {
596                 rcu_read_unlock();
597                 kfree_skb(ans_skb);
598                 nlsze_mult++;
599                 goto list_start;
600         }
601 list_failure_lock:
602         rcu_read_unlock();
603 list_failure:
604         kfree_skb(ans_skb);
605         return ret_val;
606 }
607
608 /**
609  * netlbl_cipsov4_listall_cb - cipso_v4_doi_walk() callback for LISTALL
610  * @doi_def: the CIPSOv4 DOI definition
611  * @arg: the netlbl_cipsov4_doiwalk_arg structure
612  *
613  * Description:
614  * This function is designed to be used as a callback to the
615  * cipso_v4_doi_walk() function for use in generating a response for a LISTALL
616  * message.  Returns the size of the message on success, negative values on
617  * failure.
618  *
619  */
620 static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg)
621 {
622         int ret_val = -ENOMEM;
623         struct netlbl_cipsov4_doiwalk_arg *cb_arg = arg;
624         void *data;
625
626         data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
627                            cb_arg->seq, &netlbl_cipsov4_gnl_family,
628                            NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL);
629         if (data == NULL)
630                 goto listall_cb_failure;
631
632         ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi);
633         if (ret_val != 0)
634                 goto listall_cb_failure;
635         ret_val = nla_put_u32(cb_arg->skb,
636                               NLBL_CIPSOV4_A_MTYPE,
637                               doi_def->type);
638         if (ret_val != 0)
639                 goto listall_cb_failure;
640
641         return genlmsg_end(cb_arg->skb, data);
642
643 listall_cb_failure:
644         genlmsg_cancel(cb_arg->skb, data);
645         return ret_val;
646 }
647
648 /**
649  * netlbl_cipsov4_listall - Handle a LISTALL message
650  * @skb: the NETLINK buffer
651  * @cb: the NETLINK callback
652  *
653  * Description:
654  * Process a user generated LISTALL message and respond accordingly.  Returns
655  * zero on success and negative values on error.
656  *
657  */
658 static int netlbl_cipsov4_listall(struct sk_buff *skb,
659                                   struct netlink_callback *cb)
660 {
661         struct netlbl_cipsov4_doiwalk_arg cb_arg;
662         int doi_skip = cb->args[0];
663
664         cb_arg.nl_cb = cb;
665         cb_arg.skb = skb;
666         cb_arg.seq = cb->nlh->nlmsg_seq;
667
668         cipso_v4_doi_walk(&doi_skip, netlbl_cipsov4_listall_cb, &cb_arg);
669
670         cb->args[0] = doi_skip;
671         return skb->len;
672 }
673
674 /**
675  * netlbl_cipsov4_remove - Handle a REMOVE message
676  * @skb: the NETLINK buffer
677  * @info: the Generic NETLINK info block
678  *
679  * Description:
680  * Process a user generated REMOVE message and respond accordingly.  Returns
681  * zero on success, negative values on failure.
682  *
683  */
684 static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
685 {
686         int ret_val = -EINVAL;
687         u32 doi = 0;
688         struct audit_buffer *audit_buf;
689         struct netlbl_audit audit_info;
690
691         if (!info->attrs[NLBL_CIPSOV4_A_DOI])
692                 return -EINVAL;
693
694         doi = nla_get_u32(info->attrs[NLBL_CIPSOV4_A_DOI]);
695         netlbl_netlink_auditinfo(skb, &audit_info);
696
697         ret_val = cipso_v4_doi_remove(doi,
698                                       &audit_info,
699                                       netlbl_cipsov4_doi_free);
700         if (ret_val == 0)
701                 netlbl_mgmt_protocount_dec();
702
703         audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_DEL,
704                                               &audit_info);
705         if (audit_buf != NULL) {
706                 audit_log_format(audit_buf,
707                                  " cipso_doi=%u res=%u",
708                                  doi,
709                                  ret_val == 0 ? 1 : 0);
710                 audit_log_end(audit_buf);
711         }
712
713         return ret_val;
714 }
715
716 /*
717  * NetLabel Generic NETLINK Command Definitions
718  */
719
720 static struct genl_ops netlbl_cipsov4_genl_c_add = {
721         .cmd = NLBL_CIPSOV4_C_ADD,
722         .flags = GENL_ADMIN_PERM,
723         .policy = netlbl_cipsov4_genl_policy,
724         .doit = netlbl_cipsov4_add,
725         .dumpit = NULL,
726 };
727
728 static struct genl_ops netlbl_cipsov4_genl_c_remove = {
729         .cmd = NLBL_CIPSOV4_C_REMOVE,
730         .flags = GENL_ADMIN_PERM,
731         .policy = netlbl_cipsov4_genl_policy,
732         .doit = netlbl_cipsov4_remove,
733         .dumpit = NULL,
734 };
735
736 static struct genl_ops netlbl_cipsov4_genl_c_list = {
737         .cmd = NLBL_CIPSOV4_C_LIST,
738         .flags = 0,
739         .policy = netlbl_cipsov4_genl_policy,
740         .doit = netlbl_cipsov4_list,
741         .dumpit = NULL,
742 };
743
744 static struct genl_ops netlbl_cipsov4_genl_c_listall = {
745         .cmd = NLBL_CIPSOV4_C_LISTALL,
746         .flags = 0,
747         .policy = netlbl_cipsov4_genl_policy,
748         .doit = NULL,
749         .dumpit = netlbl_cipsov4_listall,
750 };
751
752 /*
753  * NetLabel Generic NETLINK Protocol Functions
754  */
755
756 /**
757  * netlbl_cipsov4_genl_init - Register the CIPSOv4 NetLabel component
758  *
759  * Description:
760  * Register the CIPSOv4 packet NetLabel component with the Generic NETLINK
761  * mechanism.  Returns zero on success, negative values on failure.
762  *
763  */
764 int netlbl_cipsov4_genl_init(void)
765 {
766         int ret_val;
767
768         ret_val = genl_register_family(&netlbl_cipsov4_gnl_family);
769         if (ret_val != 0)
770                 return ret_val;
771
772         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
773                                     &netlbl_cipsov4_genl_c_add);
774         if (ret_val != 0)
775                 return ret_val;
776         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
777                                     &netlbl_cipsov4_genl_c_remove);
778         if (ret_val != 0)
779                 return ret_val;
780         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
781                                     &netlbl_cipsov4_genl_c_list);
782         if (ret_val != 0)
783                 return ret_val;
784         ret_val = genl_register_ops(&netlbl_cipsov4_gnl_family,
785                                     &netlbl_cipsov4_genl_c_listall);
786         if (ret_val != 0)
787                 return ret_val;
788
789         return 0;
790 }