Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]

Diff markup

Differences between /linux/security/keys/keyctl.c (Version 2.6.25.8) and /linux/security/keys/keyctl.c (Version 2.6.25)


  1 /* keyctl.c: userspace keyctl operations            1 /* keyctl.c: userspace keyctl operations
  2  *                                                  2  *
  3  * Copyright (C) 2004-5 Red Hat, Inc. All Righ      3  * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
  4  * Written by David Howells (dhowells@redhat.c      4  * Written by David Howells (dhowells@redhat.com)
  5  *                                                  5  *
  6  * This program is free software; you can redi      6  * This program is free software; you can redistribute it and/or
  7  * modify it under the terms of the GNU Genera      7  * modify it under the terms of the GNU General Public License
  8  * as published by the Free Software Foundatio      8  * as published by the Free Software Foundation; either version
  9  * 2 of the License, or (at your option) any l      9  * 2 of the License, or (at your option) any later version.
 10  */                                                10  */
 11                                                    11 
 12 #include <linux/module.h>                          12 #include <linux/module.h>
 13 #include <linux/init.h>                            13 #include <linux/init.h>
 14 #include <linux/sched.h>                           14 #include <linux/sched.h>
 15 #include <linux/slab.h>                            15 #include <linux/slab.h>
 16 #include <linux/syscalls.h>                        16 #include <linux/syscalls.h>
 17 #include <linux/keyctl.h>                          17 #include <linux/keyctl.h>
 18 #include <linux/fs.h>                              18 #include <linux/fs.h>
 19 #include <linux/capability.h>                      19 #include <linux/capability.h>
 20 #include <linux/string.h>                          20 #include <linux/string.h>
 21 #include <linux/err.h>                             21 #include <linux/err.h>
 22 #include <asm/uaccess.h>                           22 #include <asm/uaccess.h>
 23 #include "internal.h"                              23 #include "internal.h"
 24                                                    24 
 25 static int key_get_type_from_user(char *type,      25 static int key_get_type_from_user(char *type,
 26                                   const char _     26                                   const char __user *_type,
 27                                   unsigned len     27                                   unsigned len)
 28 {                                                  28 {
 29         int ret;                                   29         int ret;
 30                                                    30 
 31         ret = strncpy_from_user(type, _type, l     31         ret = strncpy_from_user(type, _type, len);
 32                                                    32 
 33         if (ret < 0)                               33         if (ret < 0)
 34                 return -EFAULT;                    34                 return -EFAULT;
 35                                                    35 
 36         if (ret == 0 || ret >= len)                36         if (ret == 0 || ret >= len)
 37                 return -EINVAL;                    37                 return -EINVAL;
 38                                                    38 
 39         if (type[0] == '.')                        39         if (type[0] == '.')
 40                 return -EPERM;                     40                 return -EPERM;
 41                                                    41 
 42         type[len - 1] = '\0';                      42         type[len - 1] = '\0';
 43                                                    43 
 44         return 0;                                  44         return 0;
 45 }                                                  45 }
 46                                                    46 
 47 /*********************************************     47 /*****************************************************************************/
 48 /*                                                 48 /*
 49  * extract the description of a new key from u     49  * extract the description of a new key from userspace and either add it as a
 50  * new key to the specified keyring or update      50  * new key to the specified keyring or update a matching key in that keyring
 51  * - the keyring must be writable                  51  * - the keyring must be writable
 52  * - returns the new key's serial number           52  * - returns the new key's serial number
 53  * - implements add_key()                          53  * - implements add_key()
 54  */                                                54  */
 55 asmlinkage long sys_add_key(const char __user      55 asmlinkage long sys_add_key(const char __user *_type,
 56                             const char __user      56                             const char __user *_description,
 57                             const void __user      57                             const void __user *_payload,
 58                             size_t plen,           58                             size_t plen,
 59                             key_serial_t ringi     59                             key_serial_t ringid)
 60 {                                                  60 {
 61         key_ref_t keyring_ref, key_ref;            61         key_ref_t keyring_ref, key_ref;
 62         char type[32], *description;               62         char type[32], *description;
 63         void *payload;                             63         void *payload;
 64         long ret;                                  64         long ret;
 65                                                    65 
 66         ret = -EINVAL;                             66         ret = -EINVAL;
 67         if (plen > 32767)                          67         if (plen > 32767)
 68                 goto error;                        68                 goto error;
 69                                                    69 
 70         /* draw all the data into kernel space     70         /* draw all the data into kernel space */
 71         ret = key_get_type_from_user(type, _ty     71         ret = key_get_type_from_user(type, _type, sizeof(type));
 72         if (ret < 0)                               72         if (ret < 0)
 73                 goto error;                        73                 goto error;
 74                                                    74 
 75         description = strndup_user(_descriptio     75         description = strndup_user(_description, PAGE_SIZE);
 76         if (IS_ERR(description)) {                 76         if (IS_ERR(description)) {
 77                 ret = PTR_ERR(description);        77                 ret = PTR_ERR(description);
 78                 goto error;                        78                 goto error;
 79         }                                          79         }
 80                                                    80 
 81         /* pull the payload in if one was supp     81         /* pull the payload in if one was supplied */
 82         payload = NULL;                            82         payload = NULL;
 83                                                    83 
 84         if (_payload) {                            84         if (_payload) {
 85                 ret = -ENOMEM;                     85                 ret = -ENOMEM;
 86                 payload = kmalloc(plen, GFP_KE     86                 payload = kmalloc(plen, GFP_KERNEL);
 87                 if (!payload)                      87                 if (!payload)
 88                         goto error2;               88                         goto error2;
 89                                                    89 
 90                 ret = -EFAULT;                     90                 ret = -EFAULT;
 91                 if (copy_from_user(payload, _p     91                 if (copy_from_user(payload, _payload, plen) != 0)
 92                         goto error3;               92                         goto error3;
 93         }                                          93         }
 94                                                    94 
 95         /* find the target keyring (which must     95         /* find the target keyring (which must be writable) */
 96         keyring_ref = lookup_user_key(NULL, ri     96         keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
 97         if (IS_ERR(keyring_ref)) {                 97         if (IS_ERR(keyring_ref)) {
 98                 ret = PTR_ERR(keyring_ref);        98                 ret = PTR_ERR(keyring_ref);
 99                 goto error3;                       99                 goto error3;
100         }                                         100         }
101                                                   101 
102         /* create or update the requested key     102         /* create or update the requested key and add it to the target
103          * keyring */                             103          * keyring */
104         key_ref = key_create_or_update(keyring    104         key_ref = key_create_or_update(keyring_ref, type, description,
105                                        payload    105                                        payload, plen, KEY_ALLOC_IN_QUOTA);
106         if (!IS_ERR(key_ref)) {                   106         if (!IS_ERR(key_ref)) {
107                 ret = key_ref_to_ptr(key_ref)-    107                 ret = key_ref_to_ptr(key_ref)->serial;
108                 key_ref_put(key_ref);             108                 key_ref_put(key_ref);
109         }                                         109         }
110         else {                                    110         else {
111                 ret = PTR_ERR(key_ref);           111                 ret = PTR_ERR(key_ref);
112         }                                         112         }
113                                                   113 
114         key_ref_put(keyring_ref);                 114         key_ref_put(keyring_ref);
115  error3:                                          115  error3:
116         kfree(payload);                           116         kfree(payload);
117  error2:                                          117  error2:
118         kfree(description);                       118         kfree(description);
119  error:                                           119  error:
120         return ret;                               120         return ret;
121                                                   121 
122 } /* end sys_add_key() */                         122 } /* end sys_add_key() */
123                                                   123 
124 /*********************************************    124 /*****************************************************************************/
125 /*                                                125 /*
126  * search the process keyrings for a matching     126  * search the process keyrings for a matching key
127  * - nested keyrings may also be searched if t    127  * - nested keyrings may also be searched if they have Search permission
128  * - if a key is found, it will be attached to    128  * - if a key is found, it will be attached to the destination keyring if
129  *   there's one specified                        129  *   there's one specified
130  * - /sbin/request-key will be invoked if _cal    130  * - /sbin/request-key will be invoked if _callout_info is non-NULL
131  *   - the _callout_info string will be passed    131  *   - the _callout_info string will be passed to /sbin/request-key
132  *   - if the _callout_info string is empty, i    132  *   - if the _callout_info string is empty, it will be rendered as "-"
133  * - implements request_key()                     133  * - implements request_key()
134  */                                               134  */
135 asmlinkage long sys_request_key(const char __u    135 asmlinkage long sys_request_key(const char __user *_type,
136                                 const char __u    136                                 const char __user *_description,
137                                 const char __u    137                                 const char __user *_callout_info,
138                                 key_serial_t d    138                                 key_serial_t destringid)
139 {                                                 139 {
140         struct key_type *ktype;                   140         struct key_type *ktype;
141         struct key *key;                          141         struct key *key;
142         key_ref_t dest_ref;                       142         key_ref_t dest_ref;
143         char type[32], *description, *callout_    143         char type[32], *description, *callout_info;
144         long ret;                                 144         long ret;
145                                                   145 
146         /* pull the type into kernel space */     146         /* pull the type into kernel space */
147         ret = key_get_type_from_user(type, _ty    147         ret = key_get_type_from_user(type, _type, sizeof(type));
148         if (ret < 0)                              148         if (ret < 0)
149                 goto error;                       149                 goto error;
150                                                   150 
151         /* pull the description into kernel sp    151         /* pull the description into kernel space */
152         description = strndup_user(_descriptio    152         description = strndup_user(_description, PAGE_SIZE);
153         if (IS_ERR(description)) {                153         if (IS_ERR(description)) {
154                 ret = PTR_ERR(description);       154                 ret = PTR_ERR(description);
155                 goto error;                       155                 goto error;
156         }                                         156         }
157                                                   157 
158         /* pull the callout info into kernel s    158         /* pull the callout info into kernel space */
159         callout_info = NULL;                      159         callout_info = NULL;
160         if (_callout_info) {                      160         if (_callout_info) {
161                 callout_info = strndup_user(_c    161                 callout_info = strndup_user(_callout_info, PAGE_SIZE);
162                 if (IS_ERR(callout_info)) {       162                 if (IS_ERR(callout_info)) {
163                         ret = PTR_ERR(callout_    163                         ret = PTR_ERR(callout_info);
164                         goto error2;              164                         goto error2;
165                 }                                 165                 }
166         }                                         166         }
167                                                   167 
168         /* get the destination keyring if spec    168         /* get the destination keyring if specified */
169         dest_ref = NULL;                          169         dest_ref = NULL;
170         if (destringid) {                         170         if (destringid) {
171                 dest_ref = lookup_user_key(NUL    171                 dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
172                 if (IS_ERR(dest_ref)) {           172                 if (IS_ERR(dest_ref)) {
173                         ret = PTR_ERR(dest_ref    173                         ret = PTR_ERR(dest_ref);
174                         goto error3;              174                         goto error3;
175                 }                                 175                 }
176         }                                         176         }
177                                                   177 
178         /* find the key type */                   178         /* find the key type */
179         ktype = key_type_lookup(type);            179         ktype = key_type_lookup(type);
180         if (IS_ERR(ktype)) {                      180         if (IS_ERR(ktype)) {
181                 ret = PTR_ERR(ktype);             181                 ret = PTR_ERR(ktype);
182                 goto error4;                      182                 goto error4;
183         }                                         183         }
184                                                   184 
185         /* do the search */                       185         /* do the search */
186         key = request_key_and_link(ktype, desc    186         key = request_key_and_link(ktype, description, callout_info, NULL,
187                                    key_ref_to_    187                                    key_ref_to_ptr(dest_ref),
188                                    KEY_ALLOC_I    188                                    KEY_ALLOC_IN_QUOTA);
189         if (IS_ERR(key)) {                        189         if (IS_ERR(key)) {
190                 ret = PTR_ERR(key);               190                 ret = PTR_ERR(key);
191                 goto error5;                      191                 goto error5;
192         }                                         192         }
193                                                   193 
194         ret = key->serial;                        194         ret = key->serial;
195                                                   195 
196         key_put(key);                             196         key_put(key);
197  error5:                                          197  error5:
198         key_type_put(ktype);                      198         key_type_put(ktype);
199  error4:                                          199  error4:
200         key_ref_put(dest_ref);                    200         key_ref_put(dest_ref);
201  error3:                                          201  error3:
202         kfree(callout_info);                      202         kfree(callout_info);
203  error2:                                          203  error2:
204         kfree(description);                       204         kfree(description);
205  error:                                           205  error:
206         return ret;                               206         return ret;
207                                                   207 
208 } /* end sys_request_key() */                     208 } /* end sys_request_key() */
209                                                   209 
210 /*********************************************    210 /*****************************************************************************/
211 /*                                                211 /*
212  * get the ID of the specified process keyring    212  * get the ID of the specified process keyring
213  * - the keyring must have search permission t    213  * - the keyring must have search permission to be found
214  * - implements keyctl(KEYCTL_GET_KEYRING_ID)     214  * - implements keyctl(KEYCTL_GET_KEYRING_ID)
215  */                                               215  */
216 long keyctl_get_keyring_ID(key_serial_t id, in    216 long keyctl_get_keyring_ID(key_serial_t id, int create)
217 {                                                 217 {
218         key_ref_t key_ref;                        218         key_ref_t key_ref;
219         long ret;                                 219         long ret;
220                                                   220 
221         key_ref = lookup_user_key(NULL, id, cr    221         key_ref = lookup_user_key(NULL, id, create, 0, KEY_SEARCH);
222         if (IS_ERR(key_ref)) {                    222         if (IS_ERR(key_ref)) {
223                 ret = PTR_ERR(key_ref);           223                 ret = PTR_ERR(key_ref);
224                 goto error;                       224                 goto error;
225         }                                         225         }
226                                                   226 
227         ret = key_ref_to_ptr(key_ref)->serial;    227         ret = key_ref_to_ptr(key_ref)->serial;
228         key_ref_put(key_ref);                     228         key_ref_put(key_ref);
229  error:                                           229  error:
230         return ret;                               230         return ret;
231                                                   231 
232 } /* end keyctl_get_keyring_ID() */               232 } /* end keyctl_get_keyring_ID() */
233                                                   233 
234 /*********************************************    234 /*****************************************************************************/
235 /*                                                235 /*
236  * join the session keyring                       236  * join the session keyring
237  * - implements keyctl(KEYCTL_JOIN_SESSION_KEY    237  * - implements keyctl(KEYCTL_JOIN_SESSION_KEYRING)
238  */                                               238  */
239 long keyctl_join_session_keyring(const char __    239 long keyctl_join_session_keyring(const char __user *_name)
240 {                                                 240 {
241         char *name;                               241         char *name;
242         long ret;                                 242         long ret;
243                                                   243 
244         /* fetch the name from userspace */       244         /* fetch the name from userspace */
245         name = NULL;                              245         name = NULL;
246         if (_name) {                              246         if (_name) {
247                 name = strndup_user(_name, PAG    247                 name = strndup_user(_name, PAGE_SIZE);
248                 if (IS_ERR(name)) {               248                 if (IS_ERR(name)) {
249                         ret = PTR_ERR(name);      249                         ret = PTR_ERR(name);
250                         goto error;               250                         goto error;
251                 }                                 251                 }
252         }                                         252         }
253                                                   253 
254         /* join the session */                    254         /* join the session */
255         ret = join_session_keyring(name);         255         ret = join_session_keyring(name);
256                                                   256 
257  error:                                           257  error:
258         return ret;                               258         return ret;
259                                                   259 
260 } /* end keyctl_join_session_keyring() */         260 } /* end keyctl_join_session_keyring() */
261                                                   261 
262 /*********************************************    262 /*****************************************************************************/
263 /*                                                263 /*
264  * update a key's data payload                    264  * update a key's data payload
265  * - the key must be writable                     265  * - the key must be writable
266  * - implements keyctl(KEYCTL_UPDATE)             266  * - implements keyctl(KEYCTL_UPDATE)
267  */                                               267  */
268 long keyctl_update_key(key_serial_t id,           268 long keyctl_update_key(key_serial_t id,
269                        const void __user *_pay    269                        const void __user *_payload,
270                        size_t plen)               270                        size_t plen)
271 {                                                 271 {
272         key_ref_t key_ref;                        272         key_ref_t key_ref;
273         void *payload;                            273         void *payload;
274         long ret;                                 274         long ret;
275                                                   275 
276         ret = -EINVAL;                            276         ret = -EINVAL;
277         if (plen > PAGE_SIZE)                     277         if (plen > PAGE_SIZE)
278                 goto error;                       278                 goto error;
279                                                   279 
280         /* pull the payload in if one was supp    280         /* pull the payload in if one was supplied */
281         payload = NULL;                           281         payload = NULL;
282         if (_payload) {                           282         if (_payload) {
283                 ret = -ENOMEM;                    283                 ret = -ENOMEM;
284                 payload = kmalloc(plen, GFP_KE    284                 payload = kmalloc(plen, GFP_KERNEL);
285                 if (!payload)                     285                 if (!payload)
286                         goto error;               286                         goto error;
287                                                   287 
288                 ret = -EFAULT;                    288                 ret = -EFAULT;
289                 if (copy_from_user(payload, _p    289                 if (copy_from_user(payload, _payload, plen) != 0)
290                         goto error2;              290                         goto error2;
291         }                                         291         }
292                                                   292 
293         /* find the target key (which must be     293         /* find the target key (which must be writable) */
294         key_ref = lookup_user_key(NULL, id, 0,    294         key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
295         if (IS_ERR(key_ref)) {                    295         if (IS_ERR(key_ref)) {
296                 ret = PTR_ERR(key_ref);           296                 ret = PTR_ERR(key_ref);
297                 goto error2;                      297                 goto error2;
298         }                                         298         }
299                                                   299 
300         /* update the key */                      300         /* update the key */
301         ret = key_update(key_ref, payload, ple    301         ret = key_update(key_ref, payload, plen);
302                                                   302 
303         key_ref_put(key_ref);                     303         key_ref_put(key_ref);
304  error2:                                          304  error2:
305         kfree(payload);                           305         kfree(payload);
306  error:                                           306  error:
307         return ret;                               307         return ret;
308                                                   308 
309 } /* end keyctl_update_key() */                   309 } /* end keyctl_update_key() */
310                                                   310 
311 /*********************************************    311 /*****************************************************************************/
312 /*                                                312 /*
313  * revoke a key                                   313  * revoke a key
314  * - the key must be writable                     314  * - the key must be writable
315  * - implements keyctl(KEYCTL_REVOKE)             315  * - implements keyctl(KEYCTL_REVOKE)
316  */                                               316  */
317 long keyctl_revoke_key(key_serial_t id)           317 long keyctl_revoke_key(key_serial_t id)
318 {                                                 318 {
319         key_ref_t key_ref;                        319         key_ref_t key_ref;
320         long ret;                                 320         long ret;
321                                                   321 
322         key_ref = lookup_user_key(NULL, id, 0,    322         key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE);
323         if (IS_ERR(key_ref)) {                    323         if (IS_ERR(key_ref)) {
324                 ret = PTR_ERR(key_ref);           324                 ret = PTR_ERR(key_ref);
325                 goto error;                       325                 goto error;
326         }                                         326         }
327                                                   327 
328         key_revoke(key_ref_to_ptr(key_ref));      328         key_revoke(key_ref_to_ptr(key_ref));
329         ret = 0;                                  329         ret = 0;
330                                                   330 
331         key_ref_put(key_ref);                     331         key_ref_put(key_ref);
332  error:                                           332  error:
333         return ret;                               333         return ret;
334                                                   334 
335 } /* end keyctl_revoke_key() */                   335 } /* end keyctl_revoke_key() */
336                                                   336 
337 /*********************************************    337 /*****************************************************************************/
338 /*                                                338 /*
339  * clear the specified process keyring            339  * clear the specified process keyring
340  * - the keyring must be writable                 340  * - the keyring must be writable
341  * - implements keyctl(KEYCTL_CLEAR)              341  * - implements keyctl(KEYCTL_CLEAR)
342  */                                               342  */
343 long keyctl_keyring_clear(key_serial_t ringid)    343 long keyctl_keyring_clear(key_serial_t ringid)
344 {                                                 344 {
345         key_ref_t keyring_ref;                    345         key_ref_t keyring_ref;
346         long ret;                                 346         long ret;
347                                                   347 
348         keyring_ref = lookup_user_key(NULL, ri    348         keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
349         if (IS_ERR(keyring_ref)) {                349         if (IS_ERR(keyring_ref)) {
350                 ret = PTR_ERR(keyring_ref);       350                 ret = PTR_ERR(keyring_ref);
351                 goto error;                       351                 goto error;
352         }                                         352         }
353                                                   353 
354         ret = keyring_clear(key_ref_to_ptr(key    354         ret = keyring_clear(key_ref_to_ptr(keyring_ref));
355                                                   355 
356         key_ref_put(keyring_ref);                 356         key_ref_put(keyring_ref);
357  error:                                           357  error:
358         return ret;                               358         return ret;
359                                                   359 
360 } /* end keyctl_keyring_clear() */                360 } /* end keyctl_keyring_clear() */
361                                                   361 
362 /*********************************************    362 /*****************************************************************************/
363 /*                                                363 /*
364  * link a key into a keyring                      364  * link a key into a keyring
365  * - the keyring must be writable                 365  * - the keyring must be writable
366  * - the key must be linkable                     366  * - the key must be linkable
367  * - implements keyctl(KEYCTL_LINK)               367  * - implements keyctl(KEYCTL_LINK)
368  */                                               368  */
369 long keyctl_keyring_link(key_serial_t id, key_    369 long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
370 {                                                 370 {
371         key_ref_t keyring_ref, key_ref;           371         key_ref_t keyring_ref, key_ref;
372         long ret;                                 372         long ret;
373                                                   373 
374         keyring_ref = lookup_user_key(NULL, ri    374         keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
375         if (IS_ERR(keyring_ref)) {                375         if (IS_ERR(keyring_ref)) {
376                 ret = PTR_ERR(keyring_ref);       376                 ret = PTR_ERR(keyring_ref);
377                 goto error;                       377                 goto error;
378         }                                         378         }
379                                                   379 
380         key_ref = lookup_user_key(NULL, id, 1,    380         key_ref = lookup_user_key(NULL, id, 1, 0, KEY_LINK);
381         if (IS_ERR(key_ref)) {                    381         if (IS_ERR(key_ref)) {
382                 ret = PTR_ERR(key_ref);           382                 ret = PTR_ERR(key_ref);
383                 goto error2;                      383                 goto error2;
384         }                                         384         }
385                                                   385 
386         ret = key_link(key_ref_to_ptr(keyring_    386         ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
387                                                   387 
388         key_ref_put(key_ref);                     388         key_ref_put(key_ref);
389  error2:                                          389  error2:
390         key_ref_put(keyring_ref);                 390         key_ref_put(keyring_ref);
391  error:                                           391  error:
392         return ret;                               392         return ret;
393                                                   393 
394 } /* end keyctl_keyring_link() */                 394 } /* end keyctl_keyring_link() */
395                                                   395 
396 /*********************************************    396 /*****************************************************************************/
397 /*                                                397 /*
398  * unlink the first attachment of a key from a    398  * unlink the first attachment of a key from a keyring
399  * - the keyring must be writable                 399  * - the keyring must be writable
400  * - we don't need any permissions on the key     400  * - we don't need any permissions on the key
401  * - implements keyctl(KEYCTL_UNLINK)             401  * - implements keyctl(KEYCTL_UNLINK)
402  */                                               402  */
403 long keyctl_keyring_unlink(key_serial_t id, ke    403 long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
404 {                                                 404 {
405         key_ref_t keyring_ref, key_ref;           405         key_ref_t keyring_ref, key_ref;
406         long ret;                                 406         long ret;
407                                                   407 
408         keyring_ref = lookup_user_key(NULL, ri    408         keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE);
409         if (IS_ERR(keyring_ref)) {                409         if (IS_ERR(keyring_ref)) {
410                 ret = PTR_ERR(keyring_ref);       410                 ret = PTR_ERR(keyring_ref);
411                 goto error;                       411                 goto error;
412         }                                         412         }
413                                                   413 
414         key_ref = lookup_user_key(NULL, id, 0,    414         key_ref = lookup_user_key(NULL, id, 0, 0, 0);
415         if (IS_ERR(key_ref)) {                    415         if (IS_ERR(key_ref)) {
416                 ret = PTR_ERR(key_ref);           416                 ret = PTR_ERR(key_ref);
417                 goto error2;                      417                 goto error2;
418         }                                         418         }
419                                                   419 
420         ret = key_unlink(key_ref_to_ptr(keyrin    420         ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
421                                                   421 
422         key_ref_put(key_ref);                     422         key_ref_put(key_ref);
423  error2:                                          423  error2:
424         key_ref_put(keyring_ref);                 424         key_ref_put(keyring_ref);
425  error:                                           425  error:
426         return ret;                               426         return ret;
427                                                   427 
428 } /* end keyctl_keyring_unlink() */               428 } /* end keyctl_keyring_unlink() */
429                                                   429 
430 /*********************************************    430 /*****************************************************************************/
431 /*                                                431 /*
432  * describe a user key                            432  * describe a user key
433  * - the key must have view permission            433  * - the key must have view permission
434  * - if there's a buffer, we place up to bufle    434  * - if there's a buffer, we place up to buflen bytes of data into it
435  * - unless there's an error, we return the am    435  * - unless there's an error, we return the amount of description available,
436  *   irrespective of how much we may have copi    436  *   irrespective of how much we may have copied
437  * - the description is formatted thus:           437  * - the description is formatted thus:
438  *      type;uid;gid;perm;description<NUL>        438  *      type;uid;gid;perm;description<NUL>
439  * - implements keyctl(KEYCTL_DESCRIBE)           439  * - implements keyctl(KEYCTL_DESCRIBE)
440  */                                               440  */
441 long keyctl_describe_key(key_serial_t keyid,      441 long keyctl_describe_key(key_serial_t keyid,
442                          char __user *buffer,     442                          char __user *buffer,
443                          size_t buflen)           443                          size_t buflen)
444 {                                                 444 {
445         struct key *key, *instkey;                445         struct key *key, *instkey;
446         key_ref_t key_ref;                        446         key_ref_t key_ref;
447         char *tmpbuf;                             447         char *tmpbuf;
448         long ret;                                 448         long ret;
449                                                   449 
450         key_ref = lookup_user_key(NULL, keyid,    450         key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW);
451         if (IS_ERR(key_ref)) {                    451         if (IS_ERR(key_ref)) {
452                 /* viewing a key under constru    452                 /* viewing a key under construction is permitted if we have the
453                  * authorisation token handy *    453                  * authorisation token handy */
454                 if (PTR_ERR(key_ref) == -EACCE    454                 if (PTR_ERR(key_ref) == -EACCES) {
455                         instkey = key_get_inst    455                         instkey = key_get_instantiation_authkey(keyid);
456                         if (!IS_ERR(instkey))     456                         if (!IS_ERR(instkey)) {
457                                 key_put(instke    457                                 key_put(instkey);
458                                 key_ref = look    458                                 key_ref = lookup_user_key(NULL, keyid,
459                                                   459                                                           0, 1, 0);
460                                 if (!IS_ERR(ke    460                                 if (!IS_ERR(key_ref))
461                                         goto o    461                                         goto okay;
462                         }                         462                         }
463                 }                                 463                 }
464                                                   464 
465                 ret = PTR_ERR(key_ref);           465                 ret = PTR_ERR(key_ref);
466                 goto error;                       466                 goto error;
467         }                                         467         }
468                                                   468 
469 okay:                                             469 okay:
470         /* calculate how much description we'r    470         /* calculate how much description we're going to return */
471         ret = -ENOMEM;                            471         ret = -ENOMEM;
472         tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL    472         tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
473         if (!tmpbuf)                              473         if (!tmpbuf)
474                 goto error2;                      474                 goto error2;
475                                                   475 
476         key = key_ref_to_ptr(key_ref);            476         key = key_ref_to_ptr(key_ref);
477                                                   477 
478         ret = snprintf(tmpbuf, PAGE_SIZE - 1,     478         ret = snprintf(tmpbuf, PAGE_SIZE - 1,
479                        "%s;%d;%d;%08x;%s",        479                        "%s;%d;%d;%08x;%s",
480                        key_ref_to_ptr(key_ref)    480                        key_ref_to_ptr(key_ref)->type->name,
481                        key_ref_to_ptr(key_ref)    481                        key_ref_to_ptr(key_ref)->uid,
482                        key_ref_to_ptr(key_ref)    482                        key_ref_to_ptr(key_ref)->gid,
483                        key_ref_to_ptr(key_ref)    483                        key_ref_to_ptr(key_ref)->perm,
484                        key_ref_to_ptr(key_ref)    484                        key_ref_to_ptr(key_ref)->description ?
485                        key_ref_to_ptr(key_ref)    485                        key_ref_to_ptr(key_ref)->description : ""
486                        );                         486                        );
487                                                   487 
488         /* include a NUL char at the end of th    488         /* include a NUL char at the end of the data */
489         if (ret > PAGE_SIZE - 1)                  489         if (ret > PAGE_SIZE - 1)
490                 ret = PAGE_SIZE - 1;              490                 ret = PAGE_SIZE - 1;
491         tmpbuf[ret] = 0;                          491         tmpbuf[ret] = 0;
492         ret++;                                    492         ret++;
493                                                   493 
494         /* consider returning the data */         494         /* consider returning the data */
495         if (buffer && buflen > 0) {               495         if (buffer && buflen > 0) {
496                 if (buflen > ret)                 496                 if (buflen > ret)
497                         buflen = ret;             497                         buflen = ret;
498                                                   498 
499                 if (copy_to_user(buffer, tmpbu    499                 if (copy_to_user(buffer, tmpbuf, buflen) != 0)
500                         ret = -EFAULT;            500                         ret = -EFAULT;
501         }                                         501         }
502                                                   502 
503         kfree(tmpbuf);                            503         kfree(tmpbuf);
504  error2:                                          504  error2:
505         key_ref_put(key_ref);                     505         key_ref_put(key_ref);
506  error:                                           506  error:
507         return ret;                               507         return ret;
508                                                   508 
509 } /* end keyctl_describe_key() */                 509 } /* end keyctl_describe_key() */
510                                                   510 
511 /*********************************************    511 /*****************************************************************************/
512 /*                                                512 /*
513  * search the specified keyring for a matching    513  * search the specified keyring for a matching key
514  * - the start keyring must be searchable         514  * - the start keyring must be searchable
515  * - nested keyrings may also be searched if t    515  * - nested keyrings may also be searched if they are searchable
516  * - only keys with search permission may be f    516  * - only keys with search permission may be found
517  * - if a key is found, it will be attached to    517  * - if a key is found, it will be attached to the destination keyring if
518  *   there's one specified                        518  *   there's one specified
519  * - implements keyctl(KEYCTL_SEARCH)             519  * - implements keyctl(KEYCTL_SEARCH)
520  */                                               520  */
521 long keyctl_keyring_search(key_serial_t ringid    521 long keyctl_keyring_search(key_serial_t ringid,
522                            const char __user *    522                            const char __user *_type,
523                            const char __user *    523                            const char __user *_description,
524                            key_serial_t destri    524                            key_serial_t destringid)
525 {                                                 525 {
526         struct key_type *ktype;                   526         struct key_type *ktype;
527         key_ref_t keyring_ref, key_ref, dest_r    527         key_ref_t keyring_ref, key_ref, dest_ref;
528         char type[32], *description;              528         char type[32], *description;
529         long ret;                                 529         long ret;
530                                                   530 
531         /* pull the type and description into     531         /* pull the type and description into kernel space */
532         ret = key_get_type_from_user(type, _ty    532         ret = key_get_type_from_user(type, _type, sizeof(type));
533         if (ret < 0)                              533         if (ret < 0)
534                 goto error;                       534                 goto error;
535                                                   535 
536         description = strndup_user(_descriptio    536         description = strndup_user(_description, PAGE_SIZE);
537         if (IS_ERR(description)) {                537         if (IS_ERR(description)) {
538                 ret = PTR_ERR(description);       538                 ret = PTR_ERR(description);
539                 goto error;                       539                 goto error;
540         }                                         540         }
541                                                   541 
542         /* get the keyring at which to begin t    542         /* get the keyring at which to begin the search */
543         keyring_ref = lookup_user_key(NULL, ri    543         keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH);
544         if (IS_ERR(keyring_ref)) {                544         if (IS_ERR(keyring_ref)) {
545                 ret = PTR_ERR(keyring_ref);       545                 ret = PTR_ERR(keyring_ref);
546                 goto error2;                      546                 goto error2;
547         }                                         547         }
548                                                   548 
549         /* get the destination keyring if spec    549         /* get the destination keyring if specified */
550         dest_ref = NULL;                          550         dest_ref = NULL;
551         if (destringid) {                         551         if (destringid) {
552                 dest_ref = lookup_user_key(NUL    552                 dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE);
553                 if (IS_ERR(dest_ref)) {           553                 if (IS_ERR(dest_ref)) {
554                         ret = PTR_ERR(dest_ref    554                         ret = PTR_ERR(dest_ref);
555                         goto error3;              555                         goto error3;
556                 }                                 556                 }
557         }                                         557         }
558                                                   558 
559         /* find the key type */                   559         /* find the key type */
560         ktype = key_type_lookup(type);            560         ktype = key_type_lookup(type);
561         if (IS_ERR(ktype)) {                      561         if (IS_ERR(ktype)) {
562                 ret = PTR_ERR(ktype);             562                 ret = PTR_ERR(ktype);
563                 goto error4;                      563                 goto error4;
564         }                                         564         }
565                                                   565 
566         /* do the search */                       566         /* do the search */
567         key_ref = keyring_search(keyring_ref,     567         key_ref = keyring_search(keyring_ref, ktype, description);
568         if (IS_ERR(key_ref)) {                    568         if (IS_ERR(key_ref)) {
569                 ret = PTR_ERR(key_ref);           569                 ret = PTR_ERR(key_ref);
570                                                   570 
571                 /* treat lack or presence of a    571                 /* treat lack or presence of a negative key the same */
572                 if (ret == -EAGAIN)               572                 if (ret == -EAGAIN)
573                         ret = -ENOKEY;            573                         ret = -ENOKEY;
574                 goto error5;                      574                 goto error5;
575         }                                         575         }
576                                                   576 
577         /* link the resulting key to the desti    577         /* link the resulting key to the destination keyring if we can */
578         if (dest_ref) {                           578         if (dest_ref) {
579                 ret = key_permission(key_ref,     579                 ret = key_permission(key_ref, KEY_LINK);
580                 if (ret < 0)                      580                 if (ret < 0)
581                         goto error6;              581                         goto error6;
582                                                   582 
583                 ret = key_link(key_ref_to_ptr(    583                 ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
584                 if (ret < 0)                      584                 if (ret < 0)
585                         goto error6;              585                         goto error6;
586         }                                         586         }
587                                                   587 
588         ret = key_ref_to_ptr(key_ref)->serial;    588         ret = key_ref_to_ptr(key_ref)->serial;
589                                                   589 
590  error6:                                          590  error6:
591         key_ref_put(key_ref);                     591         key_ref_put(key_ref);
592  error5:                                          592  error5:
593         key_type_put(ktype);                      593         key_type_put(ktype);
594  error4:                                          594  error4:
595         key_ref_put(dest_ref);                    595         key_ref_put(dest_ref);
596  error3:                                          596  error3:
597         key_ref_put(keyring_ref);                 597         key_ref_put(keyring_ref);
598  error2:                                          598  error2:
599         kfree(description);                       599         kfree(description);
600  error:                                           600  error:
601         return ret;                               601         return ret;
602                                                   602 
603 } /* end keyctl_keyring_search() */               603 } /* end keyctl_keyring_search() */
604                                                   604 
605 /*********************************************    605 /*****************************************************************************/
606 /*                                                606 /*
607  * read a user key's payload                      607  * read a user key's payload
608  * - the keyring must be readable or the key m    608  * - the keyring must be readable or the key must be searchable from the
609  *   process's keyrings                           609  *   process's keyrings
610  * - if there's a buffer, we place up to bufle    610  * - if there's a buffer, we place up to buflen bytes of data into it
611  * - unless there's an error, we return the am    611  * - unless there's an error, we return the amount of data in the key,
612  *   irrespective of how much we may have copi    612  *   irrespective of how much we may have copied
613  * - implements keyctl(KEYCTL_READ)               613  * - implements keyctl(KEYCTL_READ)
614  */                                               614  */
615 long keyctl_read_key(key_serial_t keyid, char     615 long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
616 {                                                 616 {
617         struct key *key;                          617         struct key *key;
618         key_ref_t key_ref;                        618         key_ref_t key_ref;
619         long ret;                                 619         long ret;
620                                                   620 
621         /* find the key first */                  621         /* find the key first */
622         key_ref = lookup_user_key(NULL, keyid,    622         key_ref = lookup_user_key(NULL, keyid, 0, 0, 0);
623         if (IS_ERR(key_ref)) {                    623         if (IS_ERR(key_ref)) {
624                 ret = -ENOKEY;                    624                 ret = -ENOKEY;
625                 goto error;                       625                 goto error;
626         }                                         626         }
627                                                   627 
628         key = key_ref_to_ptr(key_ref);            628         key = key_ref_to_ptr(key_ref);
629                                                   629 
630         /* see if we can read it directly */      630         /* see if we can read it directly */
631         ret = key_permission(key_ref, KEY_READ    631         ret = key_permission(key_ref, KEY_READ);
632         if (ret == 0)                             632         if (ret == 0)
633                 goto can_read_key;                633                 goto can_read_key;
634         if (ret != -EACCES)                       634         if (ret != -EACCES)
635                 goto error;                       635                 goto error;
636                                                   636 
637         /* we can't; see if it's searchable fr    637         /* we can't; see if it's searchable from this process's keyrings
638          * - we automatically take account of     638          * - we automatically take account of the fact that it may be
639          *   dangling off an instantiation key    639          *   dangling off an instantiation key
640          */                                       640          */
641         if (!is_key_possessed(key_ref)) {         641         if (!is_key_possessed(key_ref)) {
642                 ret = -EACCES;                    642                 ret = -EACCES;
643                 goto error2;                      643                 goto error2;
644         }                                         644         }
645                                                   645 
646         /* the key is probably readable - now     646         /* the key is probably readable - now try to read it */
647  can_read_key:                                    647  can_read_key:
648         ret = key_validate(key);                  648         ret = key_validate(key);
649         if (ret == 0) {                           649         if (ret == 0) {
650                 ret = -EOPNOTSUPP;                650                 ret = -EOPNOTSUPP;
651                 if (key->type->read) {            651                 if (key->type->read) {
652                         /* read the data with     652                         /* read the data with the semaphore held (since we
653                          * might sleep) */        653                          * might sleep) */
654                         down_read(&key->sem);     654                         down_read(&key->sem);
655                         ret = key->type->read(    655                         ret = key->type->read(key, buffer, buflen);
656                         up_read(&key->sem);       656                         up_read(&key->sem);
657                 }                                 657                 }
658         }                                         658         }
659                                                   659 
660  error2:                                          660  error2:
661         key_put(key);                             661         key_put(key);
662  error:                                           662  error:
663         return ret;                               663         return ret;
664                                                   664 
665 } /* end keyctl_read_key() */                     665 } /* end keyctl_read_key() */
666                                                   666 
667 /*********************************************    667 /*****************************************************************************/
668 /*                                                668 /*
669  * change the ownership of a key                  669  * change the ownership of a key
670  * - the keyring owned by the changer             670  * - the keyring owned by the changer
671  * - if the uid or gid is -1, then that parame    671  * - if the uid or gid is -1, then that parameter is not changed
672  * - implements keyctl(KEYCTL_CHOWN)              672  * - implements keyctl(KEYCTL_CHOWN)
673  */                                               673  */
674 long keyctl_chown_key(key_serial_t id, uid_t u    674 long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
675 {                                                 675 {
676         struct key_user *newowner, *zapowner =    676         struct key_user *newowner, *zapowner = NULL;
677         struct key *key;                          677         struct key *key;
678         key_ref_t key_ref;                        678         key_ref_t key_ref;
679         long ret;                                 679         long ret;
680                                                   680 
681         ret = 0;                                  681         ret = 0;
682         if (uid == (uid_t) -1 && gid == (gid_t    682         if (uid == (uid_t) -1 && gid == (gid_t) -1)
683                 goto error;                       683                 goto error;
684                                                   684 
685         key_ref = lookup_user_key(NULL, id, 1,    685         key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
686         if (IS_ERR(key_ref)) {                    686         if (IS_ERR(key_ref)) {
687                 ret = PTR_ERR(key_ref);           687                 ret = PTR_ERR(key_ref);
688                 goto error;                       688                 goto error;
689         }                                         689         }
690                                                   690 
691         key = key_ref_to_ptr(key_ref);            691         key = key_ref_to_ptr(key_ref);
692                                                   692 
693         /* make the changes with the locks hel    693         /* make the changes with the locks held to prevent chown/chown races */
694         ret = -EACCES;                            694         ret = -EACCES;
695         down_write(&key->sem);                    695         down_write(&key->sem);
696                                                   696 
697         if (!capable(CAP_SYS_ADMIN)) {            697         if (!capable(CAP_SYS_ADMIN)) {
698                 /* only the sysadmin can chown    698                 /* only the sysadmin can chown a key to some other UID */
699                 if (uid != (uid_t) -1 && key->    699                 if (uid != (uid_t) -1 && key->uid != uid)
700                         goto error_put;           700                         goto error_put;
701                                                   701 
702                 /* only the sysadmin can set t    702                 /* only the sysadmin can set the key's GID to a group other
703                  * than one of those that the     703                  * than one of those that the current process subscribes to */
704                 if (gid != (gid_t) -1 && gid !    704                 if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid))
705                         goto error_put;           705                         goto error_put;
706         }                                         706         }
707                                                   707 
708         /* change the UID */                      708         /* change the UID */
709         if (uid != (uid_t) -1 && uid != key->u    709         if (uid != (uid_t) -1 && uid != key->uid) {
710                 ret = -ENOMEM;                    710                 ret = -ENOMEM;
711                 newowner = key_user_lookup(uid    711                 newowner = key_user_lookup(uid);
712                 if (!newowner)                    712                 if (!newowner)
713                         goto error_put;           713                         goto error_put;
714                                                   714 
715                 /* transfer the quota burden t    715                 /* transfer the quota burden to the new user */
716                 if (test_bit(KEY_FLAG_IN_QUOTA    716                 if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
717                         spin_lock(&newowner->l    717                         spin_lock(&newowner->lock);
718                         if (newowner->qnkeys +    718                         if (newowner->qnkeys + 1 >= KEYQUOTA_MAX_KEYS ||
719                             newowner->qnbytes     719                             newowner->qnbytes + key->quotalen >=
720                             KEYQUOTA_MAX_BYTES    720                             KEYQUOTA_MAX_BYTES)
721                                 goto quota_ove    721                                 goto quota_overrun;
722                                                   722 
723                         newowner->qnkeys++;       723                         newowner->qnkeys++;
724                         newowner->qnbytes += k    724                         newowner->qnbytes += key->quotalen;
725                         spin_unlock(&newowner-    725                         spin_unlock(&newowner->lock);
726                                                   726 
727                         spin_lock(&key->user->    727                         spin_lock(&key->user->lock);
728                         key->user->qnkeys--;      728                         key->user->qnkeys--;
729                         key->user->qnbytes -=     729                         key->user->qnbytes -= key->quotalen;
730                         spin_unlock(&key->user    730                         spin_unlock(&key->user->lock);
731                 }                                 731                 }
732                                                   732 
733                 atomic_dec(&key->user->nkeys);    733                 atomic_dec(&key->user->nkeys);
734                 atomic_inc(&newowner->nkeys);     734                 atomic_inc(&newowner->nkeys);
735                                                   735 
736                 if (test_bit(KEY_FLAG_INSTANTI    736                 if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
737                         atomic_dec(&key->user-    737                         atomic_dec(&key->user->nikeys);
738                         atomic_inc(&newowner->    738                         atomic_inc(&newowner->nikeys);
739                 }                                 739                 }
740                                                   740 
741                 zapowner = key->user;             741                 zapowner = key->user;
742                 key->user = newowner;             742                 key->user = newowner;
743                 key->uid = uid;                   743                 key->uid = uid;
744         }                                         744         }
745                                                   745 
746         /* change the GID */                      746         /* change the GID */
747         if (gid != (gid_t) -1)                    747         if (gid != (gid_t) -1)
748                 key->gid = gid;                   748                 key->gid = gid;
749                                                   749 
750         ret = 0;                                  750         ret = 0;
751                                                   751 
752 error_put:                                        752 error_put:
753         up_write(&key->sem);                      753         up_write(&key->sem);
754         key_put(key);                             754         key_put(key);
755         if (zapowner)                             755         if (zapowner)
756                 key_user_put(zapowner);           756                 key_user_put(zapowner);
757 error:                                            757 error:
758         return ret;                               758         return ret;
759                                                   759 
760 quota_overrun:                                    760 quota_overrun:
761         spin_unlock(&newowner->lock);             761         spin_unlock(&newowner->lock);
762         zapowner = newowner;                      762         zapowner = newowner;
763         ret = -EDQUOT;                            763         ret = -EDQUOT;
764         goto error_put;                           764         goto error_put;
765                                                   765 
766 } /* end keyctl_chown_key() */                    766 } /* end keyctl_chown_key() */
767                                                   767 
768 /*********************************************    768 /*****************************************************************************/
769 /*                                                769 /*
770  * change the permission mask on a key            770  * change the permission mask on a key
771  * - the keyring owned by the changer             771  * - the keyring owned by the changer
772  * - implements keyctl(KEYCTL_SETPERM)            772  * - implements keyctl(KEYCTL_SETPERM)
773  */                                               773  */
774 long keyctl_setperm_key(key_serial_t id, key_p    774 long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
775 {                                                 775 {
776         struct key *key;                          776         struct key *key;
777         key_ref_t key_ref;                        777         key_ref_t key_ref;
778         long ret;                                 778         long ret;
779                                                   779 
780         ret = -EINVAL;                            780         ret = -EINVAL;
781         if (perm & ~(KEY_POS_ALL | KEY_USR_ALL    781         if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
782                 goto error;                       782                 goto error;
783                                                   783 
784         key_ref = lookup_user_key(NULL, id, 1,    784         key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
785         if (IS_ERR(key_ref)) {                    785         if (IS_ERR(key_ref)) {
786                 ret = PTR_ERR(key_ref);           786                 ret = PTR_ERR(key_ref);
787                 goto error;                       787                 goto error;
788         }                                         788         }
789                                                   789 
790         key = key_ref_to_ptr(key_ref);            790         key = key_ref_to_ptr(key_ref);
791                                                   791 
792         /* make the changes with the locks hel    792         /* make the changes with the locks held to prevent chown/chmod races */
793         ret = -EACCES;                            793         ret = -EACCES;
794         down_write(&key->sem);                    794         down_write(&key->sem);
795                                                   795 
796         /* if we're not the sysadmin, we can o    796         /* if we're not the sysadmin, we can only change a key that we own */
797         if (capable(CAP_SYS_ADMIN) || key->uid    797         if (capable(CAP_SYS_ADMIN) || key->uid == current->fsuid) {
798                 key->perm = perm;                 798                 key->perm = perm;
799                 ret = 0;                          799                 ret = 0;
800         }                                         800         }
801                                                   801 
802         up_write(&key->sem);                      802         up_write(&key->sem);
803         key_put(key);                             803         key_put(key);
804 error:                                            804 error:
805         return ret;                               805         return ret;
806                                                   806 
807 } /* end keyctl_setperm_key() */                  807 } /* end keyctl_setperm_key() */
808                                                   808 
809 /*********************************************    809 /*****************************************************************************/
810 /*                                                810 /*
811  * instantiate the key with the specified payl    811  * instantiate the key with the specified payload, and, if one is given, link
812  * the key into the keyring                       812  * the key into the keyring
813  */                                               813  */
814 long keyctl_instantiate_key(key_serial_t id,      814 long keyctl_instantiate_key(key_serial_t id,
815                             const void __user     815                             const void __user *_payload,
816                             size_t plen,          816                             size_t plen,
817                             key_serial_t ringi    817                             key_serial_t ringid)
818 {                                                 818 {
819         struct request_key_auth *rka;             819         struct request_key_auth *rka;
820         struct key *instkey;                      820         struct key *instkey;
821         key_ref_t keyring_ref;                    821         key_ref_t keyring_ref;
822         void *payload;                            822         void *payload;
823         long ret;                                 823         long ret;
824                                                   824 
825         ret = -EINVAL;                            825         ret = -EINVAL;
826         if (plen > 32767)                         826         if (plen > 32767)
827                 goto error;                       827                 goto error;
828                                                   828 
829         /* the appropriate instantiation autho    829         /* the appropriate instantiation authorisation key must have been
830          * assumed before calling this */         830          * assumed before calling this */
831         ret = -EPERM;                             831         ret = -EPERM;
832         instkey = current->request_key_auth;      832         instkey = current->request_key_auth;
833         if (!instkey)                             833         if (!instkey)
834                 goto error;                       834                 goto error;
835                                                   835 
836         rka = instkey->payload.data;              836         rka = instkey->payload.data;
837         if (rka->target_key->serial != id)        837         if (rka->target_key->serial != id)
838                 goto error;                       838                 goto error;
839                                                   839 
840         /* pull the payload in if one was supp    840         /* pull the payload in if one was supplied */
841         payload = NULL;                           841         payload = NULL;
842                                                   842 
843         if (_payload) {                           843         if (_payload) {
844                 ret = -ENOMEM;                    844                 ret = -ENOMEM;
845                 payload = kmalloc(plen, GFP_KE    845                 payload = kmalloc(plen, GFP_KERNEL);
846                 if (!payload)                     846                 if (!payload)
847                         goto error;               847                         goto error;
848                                                   848 
849                 ret = -EFAULT;                    849                 ret = -EFAULT;
850                 if (copy_from_user(payload, _p    850                 if (copy_from_user(payload, _payload, plen) != 0)
851                         goto error2;              851                         goto error2;
852         }                                         852         }
853                                                   853 
854         /* find the destination keyring amongs    854         /* find the destination keyring amongst those belonging to the
855          * requesting task */                     855          * requesting task */
856         keyring_ref = NULL;                       856         keyring_ref = NULL;
857         if (ringid) {                             857         if (ringid) {
858                 keyring_ref = lookup_user_key(    858                 keyring_ref = lookup_user_key(rka->context, ringid, 1, 0,
859                                                   859                                               KEY_WRITE);
860                 if (IS_ERR(keyring_ref)) {        860                 if (IS_ERR(keyring_ref)) {
861                         ret = PTR_ERR(keyring_    861                         ret = PTR_ERR(keyring_ref);
862                         goto error2;              862                         goto error2;
863                 }                                 863                 }
864         }                                         864         }
865                                                   865 
866         /* instantiate the key and link it int    866         /* instantiate the key and link it into a keyring */
867         ret = key_instantiate_and_link(rka->ta    867         ret = key_instantiate_and_link(rka->target_key, payload, plen,
868                                        key_ref    868                                        key_ref_to_ptr(keyring_ref), instkey);
869                                                   869 
870         key_ref_put(keyring_ref);                 870         key_ref_put(keyring_ref);
871                                                   871 
872         /* discard the assumed authority if it    872         /* discard the assumed authority if it's just been disabled by
873          * instantiation of the key */            873          * instantiation of the key */
874         if (ret == 0) {                           874         if (ret == 0) {
875                 key_put(current->request_key_a    875                 key_put(current->request_key_auth);
876                 current->request_key_auth = NU    876                 current->request_key_auth = NULL;
877         }                                         877         }
878                                                   878 
879 error2:                                           879 error2:
880         kfree(payload);                           880         kfree(payload);
881 error:                                            881 error:
882         return ret;                               882         return ret;
883                                                   883 
884 } /* end keyctl_instantiate_key() */              884 } /* end keyctl_instantiate_key() */
885                                                   885 
886 /*********************************************    886 /*****************************************************************************/
887 /*                                                887 /*
888  * negatively instantiate the key with the giv    888  * negatively instantiate the key with the given timeout (in seconds), and, if
889  * one is given, link the key into the keyring    889  * one is given, link the key into the keyring
890  */                                               890  */
891 long keyctl_negate_key(key_serial_t id, unsign    891 long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
892 {                                                 892 {
893         struct request_key_auth *rka;             893         struct request_key_auth *rka;
894         struct key *instkey;                      894         struct key *instkey;
895         key_ref_t keyring_ref;                    895         key_ref_t keyring_ref;
896         long ret;                                 896         long ret;
897                                                   897 
898         /* the appropriate instantiation autho    898         /* the appropriate instantiation authorisation key must have been
899          * assumed before calling this */         899          * assumed before calling this */
900         ret = -EPERM;                             900         ret = -EPERM;
901         instkey = current->request_key_auth;      901         instkey = current->request_key_auth;
902         if (!instkey)                             902         if (!instkey)
903                 goto error;                       903                 goto error;
904                                                   904 
905         rka = instkey->payload.data;              905         rka = instkey->payload.data;
906         if (rka->target_key->serial != id)        906         if (rka->target_key->serial != id)
907                 goto error;                       907                 goto error;
908                                                   908 
909         /* find the destination keyring if pre    909         /* find the destination keyring if present (which must also be
910          * writable) */                           910          * writable) */
911         keyring_ref = NULL;                       911         keyring_ref = NULL;
912         if (ringid) {                             912         if (ringid) {
913                 keyring_ref = lookup_user_key(    913                 keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE);
914                 if (IS_ERR(keyring_ref)) {        914                 if (IS_ERR(keyring_ref)) {
915                         ret = PTR_ERR(keyring_    915                         ret = PTR_ERR(keyring_ref);
916                         goto error;               916                         goto error;
917                 }                                 917                 }
918         }                                         918         }
919                                                   919 
920         /* instantiate the key and link it int    920         /* instantiate the key and link it into a keyring */
921         ret = key_negate_and_link(rka->target_    921         ret = key_negate_and_link(rka->target_key, timeout,
922                                   key_ref_to_p    922                                   key_ref_to_ptr(keyring_ref), instkey);
923                                                   923 
924         key_ref_put(keyring_ref);                 924         key_ref_put(keyring_ref);
925                                                   925 
926         /* discard the assumed authority if it    926         /* discard the assumed authority if it's just been disabled by
927          * instantiation of the key */            927          * instantiation of the key */
928         if (ret == 0) {                           928         if (ret == 0) {
929                 key_put(current->request_key_a    929                 key_put(current->request_key_auth);
930                 current->request_key_auth = NU    930                 current->request_key_auth = NULL;
931         }                                         931         }
932                                                   932 
933 error:                                            933 error:
934         return ret;                               934         return ret;
935                                                   935 
936 } /* end keyctl_negate_key() */                   936 } /* end keyctl_negate_key() */
937                                                   937 
938 /*********************************************    938 /*****************************************************************************/
939 /*                                                939 /*
940  * set the default keyring in which request_ke    940  * set the default keyring in which request_key() will cache keys
941  * - return the old setting                       941  * - return the old setting
942  */                                               942  */
943 long keyctl_set_reqkey_keyring(int reqkey_defl    943 long keyctl_set_reqkey_keyring(int reqkey_defl)
944 {                                                 944 {
945         int ret;                                  945         int ret;
946                                                   946 
947         switch (reqkey_defl) {                    947         switch (reqkey_defl) {
948         case KEY_REQKEY_DEFL_THREAD_KEYRING:      948         case KEY_REQKEY_DEFL_THREAD_KEYRING:
949                 ret = install_thread_keyring(c    949                 ret = install_thread_keyring(current);
950                 if (ret < 0)                      950                 if (ret < 0)
951                         return ret;               951                         return ret;
952                 goto set;                         952                 goto set;
953                                                   953 
954         case KEY_REQKEY_DEFL_PROCESS_KEYRING:     954         case KEY_REQKEY_DEFL_PROCESS_KEYRING:
955                 ret = install_process_keyring(    955                 ret = install_process_keyring(current);
956                 if (ret < 0)                      956                 if (ret < 0)
957                         return ret;               957                         return ret;
958                                                   958 
959         case KEY_REQKEY_DEFL_DEFAULT:             959         case KEY_REQKEY_DEFL_DEFAULT:
960         case KEY_REQKEY_DEFL_SESSION_KEYRING:     960         case KEY_REQKEY_DEFL_SESSION_KEYRING:
961         case KEY_REQKEY_DEFL_USER_KEYRING:        961         case KEY_REQKEY_DEFL_USER_KEYRING:
962         case KEY_REQKEY_DEFL_USER_SESSION_KEYR    962         case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
963         set:                                      963         set:
964                 current->jit_keyring = reqkey_    964                 current->jit_keyring = reqkey_defl;
965                                                   965 
966         case KEY_REQKEY_DEFL_NO_CHANGE:           966         case KEY_REQKEY_DEFL_NO_CHANGE:
967                 return current->jit_keyring;      967                 return current->jit_keyring;
968                                                   968 
969         case KEY_REQKEY_DEFL_GROUP_KEYRING:       969         case KEY_REQKEY_DEFL_GROUP_KEYRING:
970         default:                                  970         default:
971                 return -EINVAL;                   971                 return -EINVAL;
972         }                                         972         }
973                                                   973 
974 } /* end keyctl_set_reqkey_keyring() */           974 } /* end keyctl_set_reqkey_keyring() */
975                                                   975 
976 /*********************************************    976 /*****************************************************************************/
977 /*                                                977 /*
978  * set or clear the timeout for a key             978  * set or clear the timeout for a key
979  */                                               979  */
980 long keyctl_set_timeout(key_serial_t id, unsig    980 long keyctl_set_timeout(key_serial_t id, unsigned timeout)
981 {                                                 981 {
982         struct timespec now;                      982         struct timespec now;
983         struct key *key;                          983         struct key *key;
984         key_ref_t key_ref;                        984         key_ref_t key_ref;
985         time_t expiry;                            985         time_t expiry;
986         long ret;                                 986         long ret;
987                                                   987 
988         key_ref = lookup_user_key(NULL, id, 1,    988         key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR);
989         if (IS_ERR(key_ref)) {                    989         if (IS_ERR(key_ref)) {
990                 ret = PTR_ERR(key_ref);           990                 ret = PTR_ERR(key_ref);
991                 goto error;                       991                 goto error;
992         }                                         992         }
993                                                   993 
994         key = key_ref_to_ptr(key_ref);            994         key = key_ref_to_ptr(key_ref);
995                                                   995 
996         /* make the changes with the locks hel    996         /* make the changes with the locks held to prevent races */
997         down_write(&key->sem);                    997         down_write(&key->sem);
998                                                   998 
999         expiry = 0;                               999         expiry = 0;
1000         if (timeout > 0) {                       1000         if (timeout > 0) {
1001                 now = current_kernel_time();     1001                 now = current_kernel_time();
1002                 expiry = now.tv_sec + timeout    1002                 expiry = now.tv_sec + timeout;
1003         }                                        1003         }
1004                                                  1004 
1005         key->expiry = expiry;                    1005         key->expiry = expiry;
1006                                                  1006 
1007         up_write(&key->sem);                     1007         up_write(&key->sem);
1008         key_put(key);                            1008         key_put(key);
1009                                                  1009 
1010         ret = 0;                                 1010         ret = 0;
1011 error:                                           1011 error:
1012         return ret;                              1012         return ret;
1013                                                  1013 
1014 } /* end keyctl_set_timeout() */                 1014 } /* end keyctl_set_timeout() */
1015                                                  1015 
1016 /********************************************    1016 /*****************************************************************************/
1017 /*                                               1017 /*
1018  * assume the authority to instantiate the sp    1018  * assume the authority to instantiate the specified key
1019  */                                              1019  */
1020 long keyctl_assume_authority(key_serial_t id)    1020 long keyctl_assume_authority(key_serial_t id)
1021 {                                                1021 {
1022         struct key *authkey;                     1022         struct key *authkey;
1023         long ret;                                1023         long ret;
1024                                                  1024 
1025         /* special key IDs aren't permitted *    1025         /* special key IDs aren't permitted */
1026         ret = -EINVAL;                           1026         ret = -EINVAL;
1027         if (id < 0)                              1027         if (id < 0)
1028                 goto error;                      1028                 goto error;
1029                                                  1029 
1030         /* we divest ourselves of authority i    1030         /* we divest ourselves of authority if given an ID of 0 */
1031         if (id == 0) {                           1031         if (id == 0) {
1032                 key_put(current->request_key_    1032                 key_put(current->request_key_auth);
1033                 current->request_key_auth = N    1033                 current->request_key_auth = NULL;
1034                 ret = 0;                         1034                 ret = 0;
1035                 goto error;                      1035                 goto error;
1036         }                                        1036         }
1037                                                  1037 
1038         /* attempt to assume the authority te    1038         /* attempt to assume the authority temporarily granted to us whilst we
1039          * instantiate the specified key         1039          * instantiate the specified key
1040          * - the authorisation key must be in    1040          * - the authorisation key must be in the current task's keyrings
1041          *   somewhere                           1041          *   somewhere
1042          */                                      1042          */
1043         authkey = key_get_instantiation_authk    1043         authkey = key_get_instantiation_authkey(id);
1044         if (IS_ERR(authkey)) {                   1044         if (IS_ERR(authkey)) {
1045                 ret = PTR_ERR(authkey);          1045                 ret = PTR_ERR(authkey);
1046                 goto error;                      1046                 goto error;
1047         }                                        1047         }
1048                                                  1048 
1049         key_put(current->request_key_auth);      1049         key_put(current->request_key_auth);
1050         current->request_key_auth = authkey;     1050         current->request_key_auth = authkey;
1051         ret = authkey->serial;                   1051         ret = authkey->serial;
1052                                                  1052 
1053 error:                                           1053 error:
1054         return ret;                              1054         return ret;
1055                                                  1055 
1056 } /* end keyctl_assume_authority() */            1056 } /* end keyctl_assume_authority() */
1057                                                  1057 
1058 /********************************************    1058 /*****************************************************************************/
1059 /*                                               1059 /*
1060  * the key control system call                   1060  * the key control system call
1061  */                                              1061  */
1062 asmlinkage long sys_keyctl(int option, unsign    1062 asmlinkage long sys_keyctl(int option, unsigned long arg2, unsigned long arg3,
1063                            unsigned long arg4    1063                            unsigned long arg4, unsigned long arg5)
1064 {                                                1064 {
1065         switch (option) {                        1065         switch (option) {
1066         case KEYCTL_GET_KEYRING_ID:              1066         case KEYCTL_GET_KEYRING_ID:
1067                 return keyctl_get_keyring_ID(    1067                 return keyctl_get_keyring_ID((key_serial_t) arg2,
1068                                                  1068                                              (int) arg3);
1069                                                  1069 
1070         case KEYCTL_JOIN_SESSION_KEYRING:        1070         case KEYCTL_JOIN_SESSION_KEYRING:
1071                 return keyctl_join_session_ke    1071                 return keyctl_join_session_keyring((const char __user *) arg2);
1072                                                  1072 
1073         case KEYCTL_UPDATE:                      1073         case KEYCTL_UPDATE:
1074                 return keyctl_update_key((key    1074                 return keyctl_update_key((key_serial_t) arg2,
1075                                          (con    1075                                          (const void __user *) arg3,
1076                                          (siz    1076                                          (size_t) arg4);
1077                                                  1077 
1078         case KEYCTL_REVOKE:                      1078         case KEYCTL_REVOKE:
1079                 return keyctl_revoke_key((key    1079                 return keyctl_revoke_key((key_serial_t) arg2);
1080                                                  1080 
1081         case KEYCTL_DESCRIBE:                    1081         case KEYCTL_DESCRIBE:
1082                 return keyctl_describe_key((k    1082                 return keyctl_describe_key((key_serial_t) arg2,
1083                                            (c    1083                                            (char __user *) arg3,
1084                                            (u    1084                                            (unsigned) arg4);
1085                                                  1085 
1086         case KEYCTL_CLEAR:                       1086         case KEYCTL_CLEAR:
1087                 return keyctl_keyring_clear((    1087                 return keyctl_keyring_clear((key_serial_t) arg2);
1088                                                  1088 
1089         case KEYCTL_LINK:                        1089         case KEYCTL_LINK:
1090                 return keyctl_keyring_link((k    1090                 return keyctl_keyring_link((key_serial_t) arg2,
1091                                            (k    1091                                            (key_serial_t) arg3);
1092                                                  1092 
1093         case KEYCTL_UNLINK:                      1093         case KEYCTL_UNLINK:
1094                 return keyctl_keyring_unlink(    1094                 return keyctl_keyring_unlink((key_serial_t) arg2,
1095                                                  1095                                              (key_serial_t) arg3);
1096                                                  1096 
1097         case KEYCTL_SEARCH:                      1097         case KEYCTL_SEARCH:
1098                 return keyctl_keyring_search(    1098                 return keyctl_keyring_search((key_serial_t) arg2,
1099                                                  1099                                              (const char __user *) arg3,
1100                                                  1100                                              (const char __user *) arg4,
1101                                                  1101                                              (key_serial_t) arg5);
1102                                                  1102 
1103         case KEYCTL_READ:                        1103         case KEYCTL_READ:
1104                 return keyctl_read_key((key_s    1104                 return keyctl_read_key((key_serial_t) arg2,
1105                                        (char     1105                                        (char __user *) arg3,
1106                                        (size_    1106                                        (size_t) arg4);
1107                                                  1107 
1108         case KEYCTL_CHOWN:                       1108         case KEYCTL_CHOWN:
1109                 return keyctl_chown_key((key_    1109                 return keyctl_chown_key((key_serial_t) arg2,
1110                                         (uid_    1110                                         (uid_t) arg3,
1111                                         (gid_    1111                                         (gid_t) arg4);
1112                                                  1112 
1113         case KEYCTL_SETPERM:                     1113         case KEYCTL_SETPERM:
1114                 return keyctl_setperm_key((ke    1114                 return keyctl_setperm_key((key_serial_t) arg2,
1115                                           (ke    1115                                           (key_perm_t) arg3);
1116                                                  1116 
1117         case KEYCTL_INSTANTIATE:                 1117         case KEYCTL_INSTANTIATE:
1118                 return keyctl_instantiate_key    1118                 return keyctl_instantiate_key((key_serial_t) arg2,
1119                                                  1119                                               (const void __user *) arg3,
1120                                                  1120                                               (size_t) arg4,
1121                                                  1121                                               (key_serial_t) arg5);
1122                                                  1122 
1123         case KEYCTL_NEGATE:                      1123         case KEYCTL_NEGATE:
1124                 return keyctl_negate_key((key    1124                 return keyctl_negate_key((key_serial_t) arg2,
1125                                          (uns    1125                                          (unsigned) arg3,
1126                                          (key    1126                                          (key_serial_t) arg4);
1127                                                  1127 
1128         case KEYCTL_SET_REQKEY_KEYRING:          1128         case KEYCTL_SET_REQKEY_KEYRING:
1129                 return keyctl_set_reqkey_keyr    1129                 return keyctl_set_reqkey_keyring(arg2);
1130                                                  1130 
1131         case KEYCTL_SET_TIMEOUT:                 1131         case KEYCTL_SET_TIMEOUT:
1132                 return keyctl_set_timeout((ke    1132                 return keyctl_set_timeout((key_serial_t) arg2,
1133                                           (un    1133                                           (unsigned) arg3);
1134                                                  1134 
1135         case KEYCTL_ASSUME_AUTHORITY:            1135         case KEYCTL_ASSUME_AUTHORITY:
1136                 return keyctl_assume_authorit    1136                 return keyctl_assume_authority((key_serial_t) arg2);
1137                                                  1137 
1138         default:                                 1138         default:
1139                 return -EOPNOTSUPP;              1139                 return -EOPNOTSUPP;
1140         }                                        1140         }
1141                                                  1141 
1142 } /* end sys_keyctl() */                         1142 } /* end sys_keyctl() */
1143                                                  1143 
  This page was automatically generated by the LXR engine.