Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* keyctl.c: userspace keyctl operations |
| 2 | * |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 3 | * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/syscalls.h> |
| 17 | #include <linux/keyctl.h> |
| 18 | #include <linux/fs.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 19 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/err.h> |
| 21 | #include <asm/uaccess.h> |
| 22 | #include "internal.h" |
| 23 | |
| 24 | /*****************************************************************************/ |
| 25 | /* |
| 26 | * extract the description of a new key from userspace and either add it as a |
| 27 | * new key to the specified keyring or update a matching key in that keyring |
| 28 | * - the keyring must be writable |
| 29 | * - returns the new key's serial number |
| 30 | * - implements add_key() |
| 31 | */ |
| 32 | asmlinkage long sys_add_key(const char __user *_type, |
| 33 | const char __user *_description, |
| 34 | const void __user *_payload, |
| 35 | size_t plen, |
| 36 | key_serial_t ringid) |
| 37 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 38 | key_ref_t keyring_ref, key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | char type[32], *description; |
| 40 | void *payload; |
| 41 | long dlen, ret; |
| 42 | |
| 43 | ret = -EINVAL; |
| 44 | if (plen > 32767) |
| 45 | goto error; |
| 46 | |
| 47 | /* draw all the data into kernel space */ |
| 48 | ret = strncpy_from_user(type, _type, sizeof(type) - 1); |
| 49 | if (ret < 0) |
| 50 | goto error; |
| 51 | type[31] = '\0'; |
| 52 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 53 | ret = -EPERM; |
| 54 | if (type[0] == '.') |
| 55 | goto error; |
| 56 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | ret = -EFAULT; |
| 58 | dlen = strnlen_user(_description, PAGE_SIZE - 1); |
| 59 | if (dlen <= 0) |
| 60 | goto error; |
| 61 | |
| 62 | ret = -EINVAL; |
| 63 | if (dlen > PAGE_SIZE - 1) |
| 64 | goto error; |
| 65 | |
| 66 | ret = -ENOMEM; |
| 67 | description = kmalloc(dlen + 1, GFP_KERNEL); |
| 68 | if (!description) |
| 69 | goto error; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 70 | description[dlen] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | |
| 72 | ret = -EFAULT; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 73 | if (copy_from_user(description, _description, dlen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | goto error2; |
| 75 | |
| 76 | /* pull the payload in if one was supplied */ |
| 77 | payload = NULL; |
| 78 | |
| 79 | if (_payload) { |
| 80 | ret = -ENOMEM; |
| 81 | payload = kmalloc(plen, GFP_KERNEL); |
| 82 | if (!payload) |
| 83 | goto error2; |
| 84 | |
| 85 | ret = -EFAULT; |
| 86 | if (copy_from_user(payload, _payload, plen) != 0) |
| 87 | goto error3; |
| 88 | } |
| 89 | |
| 90 | /* find the target keyring (which must be writable) */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 91 | keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); |
| 92 | if (IS_ERR(keyring_ref)) { |
| 93 | ret = PTR_ERR(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | goto error3; |
| 95 | } |
| 96 | |
| 97 | /* create or update the requested key and add it to the target |
| 98 | * keyring */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 99 | key_ref = key_create_or_update(keyring_ref, type, description, |
| 100 | payload, plen, 0); |
| 101 | if (!IS_ERR(key_ref)) { |
| 102 | ret = key_ref_to_ptr(key_ref)->serial; |
| 103 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | } |
| 105 | else { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 106 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | } |
| 108 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 109 | key_ref_put(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | error3: |
| 111 | kfree(payload); |
| 112 | error2: |
| 113 | kfree(description); |
| 114 | error: |
| 115 | return ret; |
| 116 | |
| 117 | } /* end sys_add_key() */ |
| 118 | |
| 119 | /*****************************************************************************/ |
| 120 | /* |
| 121 | * search the process keyrings for a matching key |
| 122 | * - nested keyrings may also be searched if they have Search permission |
| 123 | * - if a key is found, it will be attached to the destination keyring if |
| 124 | * there's one specified |
| 125 | * - /sbin/request-key will be invoked if _callout_info is non-NULL |
| 126 | * - the _callout_info string will be passed to /sbin/request-key |
| 127 | * - if the _callout_info string is empty, it will be rendered as "-" |
| 128 | * - implements request_key() |
| 129 | */ |
| 130 | asmlinkage long sys_request_key(const char __user *_type, |
| 131 | const char __user *_description, |
| 132 | const char __user *_callout_info, |
| 133 | key_serial_t destringid) |
| 134 | { |
| 135 | struct key_type *ktype; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 136 | struct key *key; |
| 137 | key_ref_t dest_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | char type[32], *description, *callout_info; |
| 139 | long dlen, ret; |
| 140 | |
| 141 | /* pull the type into kernel space */ |
| 142 | ret = strncpy_from_user(type, _type, sizeof(type) - 1); |
| 143 | if (ret < 0) |
| 144 | goto error; |
| 145 | type[31] = '\0'; |
| 146 | |
David Howells | 1260f80 | 2005-08-04 11:50:01 +0100 | [diff] [blame] | 147 | ret = -EPERM; |
| 148 | if (type[0] == '.') |
| 149 | goto error; |
| 150 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | /* pull the description into kernel space */ |
| 152 | ret = -EFAULT; |
| 153 | dlen = strnlen_user(_description, PAGE_SIZE - 1); |
| 154 | if (dlen <= 0) |
| 155 | goto error; |
| 156 | |
| 157 | ret = -EINVAL; |
| 158 | if (dlen > PAGE_SIZE - 1) |
| 159 | goto error; |
| 160 | |
| 161 | ret = -ENOMEM; |
| 162 | description = kmalloc(dlen + 1, GFP_KERNEL); |
| 163 | if (!description) |
| 164 | goto error; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 165 | description[dlen] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | |
| 167 | ret = -EFAULT; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 168 | if (copy_from_user(description, _description, dlen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | goto error2; |
| 170 | |
| 171 | /* pull the callout info into kernel space */ |
| 172 | callout_info = NULL; |
| 173 | if (_callout_info) { |
| 174 | ret = -EFAULT; |
| 175 | dlen = strnlen_user(_callout_info, PAGE_SIZE - 1); |
| 176 | if (dlen <= 0) |
| 177 | goto error2; |
| 178 | |
| 179 | ret = -EINVAL; |
| 180 | if (dlen > PAGE_SIZE - 1) |
| 181 | goto error2; |
| 182 | |
| 183 | ret = -ENOMEM; |
| 184 | callout_info = kmalloc(dlen + 1, GFP_KERNEL); |
| 185 | if (!callout_info) |
| 186 | goto error2; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 187 | callout_info[dlen] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | |
| 189 | ret = -EFAULT; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 190 | if (copy_from_user(callout_info, _callout_info, dlen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | goto error3; |
| 192 | } |
| 193 | |
| 194 | /* get the destination keyring if specified */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 195 | dest_ref = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | if (destringid) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 197 | dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); |
| 198 | if (IS_ERR(dest_ref)) { |
| 199 | ret = PTR_ERR(dest_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | goto error3; |
| 201 | } |
| 202 | } |
| 203 | |
| 204 | /* find the key type */ |
| 205 | ktype = key_type_lookup(type); |
| 206 | if (IS_ERR(ktype)) { |
| 207 | ret = PTR_ERR(ktype); |
| 208 | goto error4; |
| 209 | } |
| 210 | |
| 211 | /* do the search */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 212 | key = request_key_and_link(ktype, description, callout_info, |
| 213 | key_ref_to_ptr(dest_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | if (IS_ERR(key)) { |
| 215 | ret = PTR_ERR(key); |
| 216 | goto error5; |
| 217 | } |
| 218 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | ret = key->serial; |
| 220 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 221 | key_put(key); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | error5: |
| 223 | key_type_put(ktype); |
| 224 | error4: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 225 | key_ref_put(dest_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | error3: |
| 227 | kfree(callout_info); |
| 228 | error2: |
| 229 | kfree(description); |
| 230 | error: |
| 231 | return ret; |
| 232 | |
| 233 | } /* end sys_request_key() */ |
| 234 | |
| 235 | /*****************************************************************************/ |
| 236 | /* |
| 237 | * get the ID of the specified process keyring |
| 238 | * - the keyring must have search permission to be found |
| 239 | * - implements keyctl(KEYCTL_GET_KEYRING_ID) |
| 240 | */ |
| 241 | long keyctl_get_keyring_ID(key_serial_t id, int create) |
| 242 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 243 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | long ret; |
| 245 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 246 | key_ref = lookup_user_key(NULL, id, create, 0, KEY_SEARCH); |
| 247 | if (IS_ERR(key_ref)) { |
| 248 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | goto error; |
| 250 | } |
| 251 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 252 | ret = key_ref_to_ptr(key_ref)->serial; |
| 253 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | error: |
| 255 | return ret; |
| 256 | |
| 257 | } /* end keyctl_get_keyring_ID() */ |
| 258 | |
| 259 | /*****************************************************************************/ |
| 260 | /* |
| 261 | * join the session keyring |
| 262 | * - implements keyctl(KEYCTL_JOIN_SESSION_KEYRING) |
| 263 | */ |
| 264 | long keyctl_join_session_keyring(const char __user *_name) |
| 265 | { |
| 266 | char *name; |
| 267 | long nlen, ret; |
| 268 | |
| 269 | /* fetch the name from userspace */ |
| 270 | name = NULL; |
| 271 | if (_name) { |
| 272 | ret = -EFAULT; |
| 273 | nlen = strnlen_user(_name, PAGE_SIZE - 1); |
| 274 | if (nlen <= 0) |
| 275 | goto error; |
| 276 | |
| 277 | ret = -EINVAL; |
| 278 | if (nlen > PAGE_SIZE - 1) |
| 279 | goto error; |
| 280 | |
| 281 | ret = -ENOMEM; |
| 282 | name = kmalloc(nlen + 1, GFP_KERNEL); |
| 283 | if (!name) |
| 284 | goto error; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 285 | name[nlen] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
| 287 | ret = -EFAULT; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 288 | if (copy_from_user(name, _name, nlen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | goto error2; |
| 290 | } |
| 291 | |
| 292 | /* join the session */ |
| 293 | ret = join_session_keyring(name); |
| 294 | |
| 295 | error2: |
| 296 | kfree(name); |
| 297 | error: |
| 298 | return ret; |
| 299 | |
| 300 | } /* end keyctl_join_session_keyring() */ |
| 301 | |
| 302 | /*****************************************************************************/ |
| 303 | /* |
| 304 | * update a key's data payload |
| 305 | * - the key must be writable |
| 306 | * - implements keyctl(KEYCTL_UPDATE) |
| 307 | */ |
| 308 | long keyctl_update_key(key_serial_t id, |
| 309 | const void __user *_payload, |
| 310 | size_t plen) |
| 311 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 312 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | void *payload; |
| 314 | long ret; |
| 315 | |
| 316 | ret = -EINVAL; |
| 317 | if (plen > PAGE_SIZE) |
| 318 | goto error; |
| 319 | |
| 320 | /* pull the payload in if one was supplied */ |
| 321 | payload = NULL; |
| 322 | if (_payload) { |
| 323 | ret = -ENOMEM; |
| 324 | payload = kmalloc(plen, GFP_KERNEL); |
| 325 | if (!payload) |
| 326 | goto error; |
| 327 | |
| 328 | ret = -EFAULT; |
| 329 | if (copy_from_user(payload, _payload, plen) != 0) |
| 330 | goto error2; |
| 331 | } |
| 332 | |
| 333 | /* find the target key (which must be writable) */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 334 | key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); |
| 335 | if (IS_ERR(key_ref)) { |
| 336 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | goto error2; |
| 338 | } |
| 339 | |
| 340 | /* update the key */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 341 | ret = key_update(key_ref, payload, plen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 342 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 343 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | error2: |
| 345 | kfree(payload); |
| 346 | error: |
| 347 | return ret; |
| 348 | |
| 349 | } /* end keyctl_update_key() */ |
| 350 | |
| 351 | /*****************************************************************************/ |
| 352 | /* |
| 353 | * revoke a key |
| 354 | * - the key must be writable |
| 355 | * - implements keyctl(KEYCTL_REVOKE) |
| 356 | */ |
| 357 | long keyctl_revoke_key(key_serial_t id) |
| 358 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 359 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | long ret; |
| 361 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 362 | key_ref = lookup_user_key(NULL, id, 0, 0, KEY_WRITE); |
| 363 | if (IS_ERR(key_ref)) { |
| 364 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | goto error; |
| 366 | } |
| 367 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 368 | key_revoke(key_ref_to_ptr(key_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | ret = 0; |
| 370 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 371 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | error: |
David Howells | 1260f80 | 2005-08-04 11:50:01 +0100 | [diff] [blame] | 373 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | |
| 375 | } /* end keyctl_revoke_key() */ |
| 376 | |
| 377 | /*****************************************************************************/ |
| 378 | /* |
| 379 | * clear the specified process keyring |
| 380 | * - the keyring must be writable |
| 381 | * - implements keyctl(KEYCTL_CLEAR) |
| 382 | */ |
| 383 | long keyctl_keyring_clear(key_serial_t ringid) |
| 384 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 385 | key_ref_t keyring_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | long ret; |
| 387 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 388 | keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); |
| 389 | if (IS_ERR(keyring_ref)) { |
| 390 | ret = PTR_ERR(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | goto error; |
| 392 | } |
| 393 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 394 | ret = keyring_clear(key_ref_to_ptr(keyring_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 396 | key_ref_put(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | error: |
| 398 | return ret; |
| 399 | |
| 400 | } /* end keyctl_keyring_clear() */ |
| 401 | |
| 402 | /*****************************************************************************/ |
| 403 | /* |
| 404 | * link a key into a keyring |
| 405 | * - the keyring must be writable |
| 406 | * - the key must be linkable |
| 407 | * - implements keyctl(KEYCTL_LINK) |
| 408 | */ |
| 409 | long keyctl_keyring_link(key_serial_t id, key_serial_t ringid) |
| 410 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 411 | key_ref_t keyring_ref, key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | long ret; |
| 413 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 414 | keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); |
| 415 | if (IS_ERR(keyring_ref)) { |
| 416 | ret = PTR_ERR(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | goto error; |
| 418 | } |
| 419 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 420 | key_ref = lookup_user_key(NULL, id, 1, 0, KEY_LINK); |
| 421 | if (IS_ERR(key_ref)) { |
| 422 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | goto error2; |
| 424 | } |
| 425 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 426 | ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 427 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 428 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | error2: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 430 | key_ref_put(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | error: |
| 432 | return ret; |
| 433 | |
| 434 | } /* end keyctl_keyring_link() */ |
| 435 | |
| 436 | /*****************************************************************************/ |
| 437 | /* |
| 438 | * unlink the first attachment of a key from a keyring |
| 439 | * - the keyring must be writable |
| 440 | * - we don't need any permissions on the key |
| 441 | * - implements keyctl(KEYCTL_UNLINK) |
| 442 | */ |
| 443 | long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid) |
| 444 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 445 | key_ref_t keyring_ref, key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | long ret; |
| 447 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 448 | keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_WRITE); |
| 449 | if (IS_ERR(keyring_ref)) { |
| 450 | ret = PTR_ERR(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | goto error; |
| 452 | } |
| 453 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 454 | key_ref = lookup_user_key(NULL, id, 0, 0, 0); |
| 455 | if (IS_ERR(key_ref)) { |
| 456 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | goto error2; |
| 458 | } |
| 459 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 460 | ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 462 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | error2: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 464 | key_ref_put(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | error: |
| 466 | return ret; |
| 467 | |
| 468 | } /* end keyctl_keyring_unlink() */ |
| 469 | |
| 470 | /*****************************************************************************/ |
| 471 | /* |
| 472 | * describe a user key |
| 473 | * - the key must have view permission |
| 474 | * - if there's a buffer, we place up to buflen bytes of data into it |
| 475 | * - unless there's an error, we return the amount of description available, |
| 476 | * irrespective of how much we may have copied |
| 477 | * - the description is formatted thus: |
| 478 | * type;uid;gid;perm;description<NUL> |
| 479 | * - implements keyctl(KEYCTL_DESCRIBE) |
| 480 | */ |
| 481 | long keyctl_describe_key(key_serial_t keyid, |
| 482 | char __user *buffer, |
| 483 | size_t buflen) |
| 484 | { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 485 | struct key *key, *instkey; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 486 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | char *tmpbuf; |
| 488 | long ret; |
| 489 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 490 | key_ref = lookup_user_key(NULL, keyid, 0, 1, KEY_VIEW); |
| 491 | if (IS_ERR(key_ref)) { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 492 | /* viewing a key under construction is permitted if we have the |
| 493 | * authorisation token handy */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 494 | if (PTR_ERR(key_ref) == -EACCES) { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 495 | instkey = key_get_instantiation_authkey(keyid); |
| 496 | if (!IS_ERR(instkey)) { |
| 497 | key_put(instkey); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 498 | key_ref = lookup_user_key(NULL, keyid, |
| 499 | 0, 1, 0); |
| 500 | if (!IS_ERR(key_ref)) |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 501 | goto okay; |
| 502 | } |
| 503 | } |
| 504 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 505 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | goto error; |
| 507 | } |
| 508 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 509 | okay: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | /* calculate how much description we're going to return */ |
| 511 | ret = -ENOMEM; |
| 512 | tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL); |
| 513 | if (!tmpbuf) |
| 514 | goto error2; |
| 515 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 516 | key = key_ref_to_ptr(key_ref); |
| 517 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | ret = snprintf(tmpbuf, PAGE_SIZE - 1, |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 519 | "%s;%d;%d;%08x;%s", |
| 520 | key_ref_to_ptr(key_ref)->type->name, |
| 521 | key_ref_to_ptr(key_ref)->uid, |
| 522 | key_ref_to_ptr(key_ref)->gid, |
| 523 | key_ref_to_ptr(key_ref)->perm, |
| 524 | key_ref_to_ptr(key_ref)->description ? |
| 525 | key_ref_to_ptr(key_ref)->description : "" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | ); |
| 527 | |
| 528 | /* include a NUL char at the end of the data */ |
| 529 | if (ret > PAGE_SIZE - 1) |
| 530 | ret = PAGE_SIZE - 1; |
| 531 | tmpbuf[ret] = 0; |
| 532 | ret++; |
| 533 | |
| 534 | /* consider returning the data */ |
| 535 | if (buffer && buflen > 0) { |
| 536 | if (buflen > ret) |
| 537 | buflen = ret; |
| 538 | |
| 539 | if (copy_to_user(buffer, tmpbuf, buflen) != 0) |
| 540 | ret = -EFAULT; |
| 541 | } |
| 542 | |
| 543 | kfree(tmpbuf); |
| 544 | error2: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 545 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 546 | error: |
| 547 | return ret; |
| 548 | |
| 549 | } /* end keyctl_describe_key() */ |
| 550 | |
| 551 | /*****************************************************************************/ |
| 552 | /* |
| 553 | * search the specified keyring for a matching key |
| 554 | * - the start keyring must be searchable |
| 555 | * - nested keyrings may also be searched if they are searchable |
| 556 | * - only keys with search permission may be found |
| 557 | * - if a key is found, it will be attached to the destination keyring if |
| 558 | * there's one specified |
| 559 | * - implements keyctl(KEYCTL_SEARCH) |
| 560 | */ |
| 561 | long keyctl_keyring_search(key_serial_t ringid, |
| 562 | const char __user *_type, |
| 563 | const char __user *_description, |
| 564 | key_serial_t destringid) |
| 565 | { |
| 566 | struct key_type *ktype; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 567 | key_ref_t keyring_ref, key_ref, dest_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | char type[32], *description; |
| 569 | long dlen, ret; |
| 570 | |
| 571 | /* pull the type and description into kernel space */ |
| 572 | ret = strncpy_from_user(type, _type, sizeof(type) - 1); |
| 573 | if (ret < 0) |
| 574 | goto error; |
| 575 | type[31] = '\0'; |
| 576 | |
| 577 | ret = -EFAULT; |
| 578 | dlen = strnlen_user(_description, PAGE_SIZE - 1); |
| 579 | if (dlen <= 0) |
| 580 | goto error; |
| 581 | |
| 582 | ret = -EINVAL; |
| 583 | if (dlen > PAGE_SIZE - 1) |
| 584 | goto error; |
| 585 | |
| 586 | ret = -ENOMEM; |
| 587 | description = kmalloc(dlen + 1, GFP_KERNEL); |
| 588 | if (!description) |
| 589 | goto error; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 590 | description[dlen] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | |
| 592 | ret = -EFAULT; |
Davi Arnaut | 6d94074 | 2006-02-03 03:04:46 -0800 | [diff] [blame] | 593 | if (copy_from_user(description, _description, dlen) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 594 | goto error2; |
| 595 | |
| 596 | /* get the keyring at which to begin the search */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 597 | keyring_ref = lookup_user_key(NULL, ringid, 0, 0, KEY_SEARCH); |
| 598 | if (IS_ERR(keyring_ref)) { |
| 599 | ret = PTR_ERR(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | goto error2; |
| 601 | } |
| 602 | |
| 603 | /* get the destination keyring if specified */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 604 | dest_ref = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 605 | if (destringid) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 606 | dest_ref = lookup_user_key(NULL, destringid, 1, 0, KEY_WRITE); |
| 607 | if (IS_ERR(dest_ref)) { |
| 608 | ret = PTR_ERR(dest_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | goto error3; |
| 610 | } |
| 611 | } |
| 612 | |
| 613 | /* find the key type */ |
| 614 | ktype = key_type_lookup(type); |
| 615 | if (IS_ERR(ktype)) { |
| 616 | ret = PTR_ERR(ktype); |
| 617 | goto error4; |
| 618 | } |
| 619 | |
| 620 | /* do the search */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 621 | key_ref = keyring_search(keyring_ref, ktype, description); |
| 622 | if (IS_ERR(key_ref)) { |
| 623 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 624 | |
| 625 | /* treat lack or presence of a negative key the same */ |
| 626 | if (ret == -EAGAIN) |
| 627 | ret = -ENOKEY; |
| 628 | goto error5; |
| 629 | } |
| 630 | |
| 631 | /* link the resulting key to the destination keyring if we can */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 632 | if (dest_ref) { |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 633 | ret = key_permission(key_ref, KEY_LINK); |
| 634 | if (ret < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | goto error6; |
| 636 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 637 | ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | if (ret < 0) |
| 639 | goto error6; |
| 640 | } |
| 641 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 642 | ret = key_ref_to_ptr(key_ref)->serial; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 643 | |
| 644 | error6: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 645 | key_ref_put(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | error5: |
| 647 | key_type_put(ktype); |
| 648 | error4: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 649 | key_ref_put(dest_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 650 | error3: |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 651 | key_ref_put(keyring_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | error2: |
| 653 | kfree(description); |
| 654 | error: |
| 655 | return ret; |
| 656 | |
| 657 | } /* end keyctl_keyring_search() */ |
| 658 | |
| 659 | /*****************************************************************************/ |
| 660 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 661 | * read a user key's payload |
| 662 | * - the keyring must be readable or the key must be searchable from the |
| 663 | * process's keyrings |
| 664 | * - if there's a buffer, we place up to buflen bytes of data into it |
| 665 | * - unless there's an error, we return the amount of data in the key, |
| 666 | * irrespective of how much we may have copied |
| 667 | * - implements keyctl(KEYCTL_READ) |
| 668 | */ |
| 669 | long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen) |
| 670 | { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 671 | struct key *key; |
| 672 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | long ret; |
| 674 | |
| 675 | /* find the key first */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 676 | key_ref = lookup_user_key(NULL, keyid, 0, 0, 0); |
| 677 | if (IS_ERR(key_ref)) { |
| 678 | ret = -ENOKEY; |
| 679 | goto error; |
| 680 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 681 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 682 | key = key_ref_to_ptr(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 684 | /* see if we can read it directly */ |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 685 | ret = key_permission(key_ref, KEY_READ); |
| 686 | if (ret == 0) |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 687 | goto can_read_key; |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 688 | if (ret != -EACCES) |
| 689 | goto error; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 690 | |
| 691 | /* we can't; see if it's searchable from this process's keyrings |
| 692 | * - we automatically take account of the fact that it may be |
| 693 | * dangling off an instantiation key |
| 694 | */ |
| 695 | if (!is_key_possessed(key_ref)) { |
| 696 | ret = -EACCES; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | goto error2; |
| 698 | } |
| 699 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | /* the key is probably readable - now try to read it */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | can_read_key: |
| 702 | ret = key_validate(key); |
| 703 | if (ret == 0) { |
| 704 | ret = -EOPNOTSUPP; |
| 705 | if (key->type->read) { |
| 706 | /* read the data with the semaphore held (since we |
| 707 | * might sleep) */ |
| 708 | down_read(&key->sem); |
| 709 | ret = key->type->read(key, buffer, buflen); |
| 710 | up_read(&key->sem); |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | error2: |
| 715 | key_put(key); |
| 716 | error: |
| 717 | return ret; |
| 718 | |
| 719 | } /* end keyctl_read_key() */ |
| 720 | |
| 721 | /*****************************************************************************/ |
| 722 | /* |
| 723 | * change the ownership of a key |
| 724 | * - the keyring owned by the changer |
| 725 | * - if the uid or gid is -1, then that parameter is not changed |
| 726 | * - implements keyctl(KEYCTL_CHOWN) |
| 727 | */ |
| 728 | long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid) |
| 729 | { |
| 730 | struct key *key; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 731 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | long ret; |
| 733 | |
| 734 | ret = 0; |
| 735 | if (uid == (uid_t) -1 && gid == (gid_t) -1) |
| 736 | goto error; |
| 737 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 738 | key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 739 | if (IS_ERR(key_ref)) { |
| 740 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 741 | goto error; |
| 742 | } |
| 743 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 744 | key = key_ref_to_ptr(key_ref); |
| 745 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 746 | /* make the changes with the locks held to prevent chown/chown races */ |
| 747 | ret = -EACCES; |
| 748 | down_write(&key->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 749 | |
| 750 | if (!capable(CAP_SYS_ADMIN)) { |
| 751 | /* only the sysadmin can chown a key to some other UID */ |
| 752 | if (uid != (uid_t) -1 && key->uid != uid) |
| 753 | goto no_access; |
| 754 | |
| 755 | /* only the sysadmin can set the key's GID to a group other |
| 756 | * than one of those that the current process subscribes to */ |
| 757 | if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid)) |
| 758 | goto no_access; |
| 759 | } |
| 760 | |
| 761 | /* change the UID (have to update the quotas) */ |
| 762 | if (uid != (uid_t) -1 && uid != key->uid) { |
| 763 | /* don't support UID changing yet */ |
| 764 | ret = -EOPNOTSUPP; |
| 765 | goto no_access; |
| 766 | } |
| 767 | |
| 768 | /* change the GID */ |
| 769 | if (gid != (gid_t) -1) |
| 770 | key->gid = gid; |
| 771 | |
| 772 | ret = 0; |
| 773 | |
| 774 | no_access: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | up_write(&key->sem); |
| 776 | key_put(key); |
| 777 | error: |
| 778 | return ret; |
| 779 | |
| 780 | } /* end keyctl_chown_key() */ |
| 781 | |
| 782 | /*****************************************************************************/ |
| 783 | /* |
| 784 | * change the permission mask on a key |
| 785 | * - the keyring owned by the changer |
| 786 | * - implements keyctl(KEYCTL_SETPERM) |
| 787 | */ |
| 788 | long keyctl_setperm_key(key_serial_t id, key_perm_t perm) |
| 789 | { |
| 790 | struct key *key; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 791 | key_ref_t key_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | long ret; |
| 793 | |
| 794 | ret = -EINVAL; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 795 | if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | goto error; |
| 797 | |
David Howells | 29db919 | 2005-10-30 15:02:44 -0800 | [diff] [blame] | 798 | key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR); |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 799 | if (IS_ERR(key_ref)) { |
| 800 | ret = PTR_ERR(key_ref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 801 | goto error; |
| 802 | } |
| 803 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 804 | key = key_ref_to_ptr(key_ref); |
| 805 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 806 | /* make the changes with the locks held to prevent chown/chmod races */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 807 | ret = -EACCES; |
| 808 | down_write(&key->sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 809 | |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 810 | /* if we're not the sysadmin, we can only change a key that we own */ |
| 811 | if (capable(CAP_SYS_ADMIN) || key->uid == current->fsuid) { |
| 812 | key->perm = perm; |
| 813 | ret = 0; |
| 814 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 815 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | up_write(&key->sem); |
| 817 | key_put(key); |
David Howells | 76d8aea | 2005-06-23 22:00:49 -0700 | [diff] [blame] | 818 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | return ret; |
| 820 | |
| 821 | } /* end keyctl_setperm_key() */ |
| 822 | |
| 823 | /*****************************************************************************/ |
| 824 | /* |
| 825 | * instantiate the key with the specified payload, and, if one is given, link |
| 826 | * the key into the keyring |
| 827 | */ |
| 828 | long keyctl_instantiate_key(key_serial_t id, |
| 829 | const void __user *_payload, |
| 830 | size_t plen, |
| 831 | key_serial_t ringid) |
| 832 | { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 833 | struct request_key_auth *rka; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 834 | struct key *instkey; |
| 835 | key_ref_t keyring_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | void *payload; |
| 837 | long ret; |
| 838 | |
| 839 | ret = -EINVAL; |
| 840 | if (plen > 32767) |
| 841 | goto error; |
| 842 | |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 843 | /* the appropriate instantiation authorisation key must have been |
| 844 | * assumed before calling this */ |
| 845 | ret = -EPERM; |
| 846 | instkey = current->request_key_auth; |
| 847 | if (!instkey) |
| 848 | goto error; |
| 849 | |
| 850 | rka = instkey->payload.data; |
| 851 | if (rka->target_key->serial != id) |
| 852 | goto error; |
| 853 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | /* pull the payload in if one was supplied */ |
| 855 | payload = NULL; |
| 856 | |
| 857 | if (_payload) { |
| 858 | ret = -ENOMEM; |
| 859 | payload = kmalloc(plen, GFP_KERNEL); |
| 860 | if (!payload) |
| 861 | goto error; |
| 862 | |
| 863 | ret = -EFAULT; |
| 864 | if (copy_from_user(payload, _payload, plen) != 0) |
| 865 | goto error2; |
| 866 | } |
| 867 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 868 | /* find the destination keyring amongst those belonging to the |
| 869 | * requesting task */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 870 | keyring_ref = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 871 | if (ringid) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 872 | keyring_ref = lookup_user_key(rka->context, ringid, 1, 0, |
| 873 | KEY_WRITE); |
| 874 | if (IS_ERR(keyring_ref)) { |
| 875 | ret = PTR_ERR(keyring_ref); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 876 | goto error2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 877 | } |
| 878 | } |
| 879 | |
| 880 | /* instantiate the key and link it into a keyring */ |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 881 | ret = key_instantiate_and_link(rka->target_key, payload, plen, |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 882 | key_ref_to_ptr(keyring_ref), instkey); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 884 | key_ref_put(keyring_ref); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 885 | |
| 886 | /* discard the assumed authority if it's just been disabled by |
| 887 | * instantiation of the key */ |
| 888 | if (ret == 0) { |
| 889 | key_put(current->request_key_auth); |
| 890 | current->request_key_auth = NULL; |
| 891 | } |
| 892 | |
| 893 | error2: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | kfree(payload); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 895 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | return ret; |
| 897 | |
| 898 | } /* end keyctl_instantiate_key() */ |
| 899 | |
| 900 | /*****************************************************************************/ |
| 901 | /* |
| 902 | * negatively instantiate the key with the given timeout (in seconds), and, if |
| 903 | * one is given, link the key into the keyring |
| 904 | */ |
| 905 | long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid) |
| 906 | { |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 907 | struct request_key_auth *rka; |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 908 | struct key *instkey; |
| 909 | key_ref_t keyring_ref; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | long ret; |
| 911 | |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 912 | /* the appropriate instantiation authorisation key must have been |
| 913 | * assumed before calling this */ |
| 914 | ret = -EPERM; |
| 915 | instkey = current->request_key_auth; |
| 916 | if (!instkey) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 917 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 919 | rka = instkey->payload.data; |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 920 | if (rka->target_key->serial != id) |
| 921 | goto error; |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 922 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 923 | /* find the destination keyring if present (which must also be |
| 924 | * writable) */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 925 | keyring_ref = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 926 | if (ringid) { |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 927 | keyring_ref = lookup_user_key(NULL, ringid, 1, 0, KEY_WRITE); |
| 928 | if (IS_ERR(keyring_ref)) { |
| 929 | ret = PTR_ERR(keyring_ref); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 930 | goto error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | } |
| 932 | } |
| 933 | |
| 934 | /* instantiate the key and link it into a keyring */ |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 935 | ret = key_negate_and_link(rka->target_key, timeout, |
| 936 | key_ref_to_ptr(keyring_ref), instkey); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | |
David Howells | 664cceb | 2005-09-28 17:03:15 +0100 | [diff] [blame] | 938 | key_ref_put(keyring_ref); |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 939 | |
| 940 | /* discard the assumed authority if it's just been disabled by |
| 941 | * instantiation of the key */ |
| 942 | if (ret == 0) { |
| 943 | key_put(current->request_key_auth); |
| 944 | current->request_key_auth = NULL; |
| 945 | } |
| 946 | |
| 947 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 948 | return ret; |
| 949 | |
| 950 | } /* end keyctl_negate_key() */ |
| 951 | |
| 952 | /*****************************************************************************/ |
| 953 | /* |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 954 | * set the default keyring in which request_key() will cache keys |
| 955 | * - return the old setting |
| 956 | */ |
| 957 | long keyctl_set_reqkey_keyring(int reqkey_defl) |
| 958 | { |
| 959 | int ret; |
| 960 | |
| 961 | switch (reqkey_defl) { |
| 962 | case KEY_REQKEY_DEFL_THREAD_KEYRING: |
| 963 | ret = install_thread_keyring(current); |
| 964 | if (ret < 0) |
| 965 | return ret; |
| 966 | goto set; |
| 967 | |
| 968 | case KEY_REQKEY_DEFL_PROCESS_KEYRING: |
| 969 | ret = install_process_keyring(current); |
| 970 | if (ret < 0) |
| 971 | return ret; |
| 972 | |
| 973 | case KEY_REQKEY_DEFL_DEFAULT: |
| 974 | case KEY_REQKEY_DEFL_SESSION_KEYRING: |
| 975 | case KEY_REQKEY_DEFL_USER_KEYRING: |
| 976 | case KEY_REQKEY_DEFL_USER_SESSION_KEYRING: |
| 977 | set: |
| 978 | current->jit_keyring = reqkey_defl; |
| 979 | |
| 980 | case KEY_REQKEY_DEFL_NO_CHANGE: |
| 981 | return current->jit_keyring; |
| 982 | |
| 983 | case KEY_REQKEY_DEFL_GROUP_KEYRING: |
| 984 | default: |
| 985 | return -EINVAL; |
| 986 | } |
| 987 | |
| 988 | } /* end keyctl_set_reqkey_keyring() */ |
| 989 | |
| 990 | /*****************************************************************************/ |
| 991 | /* |
David Howells | 017679c | 2006-01-08 01:02:43 -0800 | [diff] [blame] | 992 | * set or clear the timeout for a key |
| 993 | */ |
| 994 | long keyctl_set_timeout(key_serial_t id, unsigned timeout) |
| 995 | { |
| 996 | struct timespec now; |
| 997 | struct key *key; |
| 998 | key_ref_t key_ref; |
| 999 | time_t expiry; |
| 1000 | long ret; |
| 1001 | |
| 1002 | key_ref = lookup_user_key(NULL, id, 1, 1, KEY_SETATTR); |
| 1003 | if (IS_ERR(key_ref)) { |
| 1004 | ret = PTR_ERR(key_ref); |
| 1005 | goto error; |
| 1006 | } |
| 1007 | |
| 1008 | key = key_ref_to_ptr(key_ref); |
| 1009 | |
| 1010 | /* make the changes with the locks held to prevent races */ |
| 1011 | down_write(&key->sem); |
| 1012 | |
| 1013 | expiry = 0; |
| 1014 | if (timeout > 0) { |
| 1015 | now = current_kernel_time(); |
| 1016 | expiry = now.tv_sec + timeout; |
| 1017 | } |
| 1018 | |
| 1019 | key->expiry = expiry; |
| 1020 | |
| 1021 | up_write(&key->sem); |
| 1022 | key_put(key); |
| 1023 | |
| 1024 | ret = 0; |
| 1025 | error: |
| 1026 | return ret; |
| 1027 | |
| 1028 | } /* end keyctl_set_timeout() */ |
| 1029 | |
| 1030 | /*****************************************************************************/ |
| 1031 | /* |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 1032 | * assume the authority to instantiate the specified key |
| 1033 | */ |
| 1034 | long keyctl_assume_authority(key_serial_t id) |
| 1035 | { |
| 1036 | struct key *authkey; |
| 1037 | long ret; |
| 1038 | |
| 1039 | /* special key IDs aren't permitted */ |
| 1040 | ret = -EINVAL; |
| 1041 | if (id < 0) |
| 1042 | goto error; |
| 1043 | |
| 1044 | /* we divest ourselves of authority if given an ID of 0 */ |
| 1045 | if (id == 0) { |
| 1046 | key_put(current->request_key_auth); |
| 1047 | current->request_key_auth = NULL; |
| 1048 | ret = 0; |
| 1049 | goto error; |
| 1050 | } |
| 1051 | |
| 1052 | /* attempt to assume the authority temporarily granted to us whilst we |
| 1053 | * instantiate the specified key |
| 1054 | * - the authorisation key must be in the current task's keyrings |
| 1055 | * somewhere |
| 1056 | */ |
| 1057 | authkey = key_get_instantiation_authkey(id); |
| 1058 | if (IS_ERR(authkey)) { |
| 1059 | ret = PTR_ERR(authkey); |
| 1060 | goto error; |
| 1061 | } |
| 1062 | |
| 1063 | key_put(current->request_key_auth); |
| 1064 | current->request_key_auth = authkey; |
| 1065 | ret = authkey->serial; |
| 1066 | |
| 1067 | error: |
| 1068 | return ret; |
| 1069 | |
| 1070 | } /* end keyctl_assume_authority() */ |
| 1071 | |
| 1072 | /*****************************************************************************/ |
| 1073 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1074 | * the key control system call |
| 1075 | */ |
| 1076 | asmlinkage long sys_keyctl(int option, unsigned long arg2, unsigned long arg3, |
| 1077 | unsigned long arg4, unsigned long arg5) |
| 1078 | { |
| 1079 | switch (option) { |
| 1080 | case KEYCTL_GET_KEYRING_ID: |
| 1081 | return keyctl_get_keyring_ID((key_serial_t) arg2, |
| 1082 | (int) arg3); |
| 1083 | |
| 1084 | case KEYCTL_JOIN_SESSION_KEYRING: |
| 1085 | return keyctl_join_session_keyring((const char __user *) arg2); |
| 1086 | |
| 1087 | case KEYCTL_UPDATE: |
| 1088 | return keyctl_update_key((key_serial_t) arg2, |
| 1089 | (const void __user *) arg3, |
| 1090 | (size_t) arg4); |
| 1091 | |
| 1092 | case KEYCTL_REVOKE: |
| 1093 | return keyctl_revoke_key((key_serial_t) arg2); |
| 1094 | |
| 1095 | case KEYCTL_DESCRIBE: |
| 1096 | return keyctl_describe_key((key_serial_t) arg2, |
| 1097 | (char __user *) arg3, |
| 1098 | (unsigned) arg4); |
| 1099 | |
| 1100 | case KEYCTL_CLEAR: |
| 1101 | return keyctl_keyring_clear((key_serial_t) arg2); |
| 1102 | |
| 1103 | case KEYCTL_LINK: |
| 1104 | return keyctl_keyring_link((key_serial_t) arg2, |
| 1105 | (key_serial_t) arg3); |
| 1106 | |
| 1107 | case KEYCTL_UNLINK: |
| 1108 | return keyctl_keyring_unlink((key_serial_t) arg2, |
| 1109 | (key_serial_t) arg3); |
| 1110 | |
| 1111 | case KEYCTL_SEARCH: |
| 1112 | return keyctl_keyring_search((key_serial_t) arg2, |
| 1113 | (const char __user *) arg3, |
| 1114 | (const char __user *) arg4, |
| 1115 | (key_serial_t) arg5); |
| 1116 | |
| 1117 | case KEYCTL_READ: |
| 1118 | return keyctl_read_key((key_serial_t) arg2, |
| 1119 | (char __user *) arg3, |
| 1120 | (size_t) arg4); |
| 1121 | |
| 1122 | case KEYCTL_CHOWN: |
| 1123 | return keyctl_chown_key((key_serial_t) arg2, |
| 1124 | (uid_t) arg3, |
| 1125 | (gid_t) arg4); |
| 1126 | |
| 1127 | case KEYCTL_SETPERM: |
| 1128 | return keyctl_setperm_key((key_serial_t) arg2, |
| 1129 | (key_perm_t) arg3); |
| 1130 | |
| 1131 | case KEYCTL_INSTANTIATE: |
| 1132 | return keyctl_instantiate_key((key_serial_t) arg2, |
| 1133 | (const void __user *) arg3, |
| 1134 | (size_t) arg4, |
| 1135 | (key_serial_t) arg5); |
| 1136 | |
| 1137 | case KEYCTL_NEGATE: |
| 1138 | return keyctl_negate_key((key_serial_t) arg2, |
| 1139 | (unsigned) arg3, |
| 1140 | (key_serial_t) arg4); |
| 1141 | |
David Howells | 3e30148 | 2005-06-23 22:00:56 -0700 | [diff] [blame] | 1142 | case KEYCTL_SET_REQKEY_KEYRING: |
| 1143 | return keyctl_set_reqkey_keyring(arg2); |
| 1144 | |
David Howells | 017679c | 2006-01-08 01:02:43 -0800 | [diff] [blame] | 1145 | case KEYCTL_SET_TIMEOUT: |
| 1146 | return keyctl_set_timeout((key_serial_t) arg2, |
| 1147 | (unsigned) arg3); |
| 1148 | |
David Howells | b5f545c | 2006-01-08 01:02:47 -0800 | [diff] [blame] | 1149 | case KEYCTL_ASSUME_AUTHORITY: |
| 1150 | return keyctl_assume_authority((key_serial_t) arg2); |
| 1151 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1152 | default: |
| 1153 | return -EOPNOTSUPP; |
| 1154 | } |
| 1155 | |
| 1156 | } /* end sys_keyctl() */ |