Casey Schaufler | e114e47 | 2008-02-04 22:29:50 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation, version 2. |
| 7 | * |
| 8 | * Authors: |
| 9 | * Casey Schaufler <casey@schaufler-ca.com> |
| 10 | * Ahmed S. Darwish <darwish.07@gmail.com> |
| 11 | * |
| 12 | * Special thanks to the authors of selinuxfs. |
| 13 | * |
| 14 | * Karl MacMillan <kmacmillan@tresys.com> |
| 15 | * James Morris <jmorris@redhat.com> |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/vmalloc.h> |
| 21 | #include <linux/security.h> |
| 22 | #include <linux/mutex.h> |
| 23 | #include <net/netlabel.h> |
| 24 | #include <net/cipso_ipv4.h> |
| 25 | #include <linux/seq_file.h> |
| 26 | #include <linux/ctype.h> |
| 27 | #include "smack.h" |
| 28 | |
| 29 | /* |
| 30 | * smackfs pseudo filesystem. |
| 31 | */ |
| 32 | |
| 33 | enum smk_inos { |
| 34 | SMK_ROOT_INO = 2, |
| 35 | SMK_LOAD = 3, /* load policy */ |
| 36 | SMK_CIPSO = 4, /* load label -> CIPSO mapping */ |
| 37 | SMK_DOI = 5, /* CIPSO DOI */ |
| 38 | SMK_DIRECT = 6, /* CIPSO level indicating direct label */ |
| 39 | SMK_AMBIENT = 7, /* internet ambient label */ |
| 40 | SMK_NLTYPE = 8, /* label scheme to use by default */ |
| 41 | }; |
| 42 | |
| 43 | /* |
| 44 | * List locks |
| 45 | */ |
| 46 | static DEFINE_MUTEX(smack_list_lock); |
| 47 | static DEFINE_MUTEX(smack_cipso_lock); |
| 48 | |
| 49 | /* |
| 50 | * This is the "ambient" label for network traffic. |
| 51 | * If it isn't somehow marked, use this. |
| 52 | * It can be reset via smackfs/ambient |
| 53 | */ |
| 54 | char *smack_net_ambient = smack_known_floor.smk_known; |
| 55 | |
| 56 | /* |
| 57 | * This is the default packet marking scheme for network traffic. |
| 58 | * It can be reset via smackfs/nltype |
| 59 | */ |
| 60 | int smack_net_nltype = NETLBL_NLTYPE_CIPSOV4; |
| 61 | |
| 62 | /* |
| 63 | * This is the level in a CIPSO header that indicates a |
| 64 | * smack label is contained directly in the category set. |
| 65 | * It can be reset via smackfs/direct |
| 66 | */ |
| 67 | int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT; |
| 68 | |
| 69 | static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT; |
| 70 | struct smk_list_entry *smack_list; |
| 71 | |
| 72 | #define SEQ_READ_FINISHED 1 |
| 73 | |
| 74 | /* |
| 75 | * Disable concurrent writing open() operations |
| 76 | */ |
| 77 | static struct semaphore smack_write_sem; |
| 78 | |
| 79 | /* |
| 80 | * Values for parsing cipso rules |
| 81 | * SMK_DIGITLEN: Length of a digit field in a rule. |
| 82 | * SMK_CIPSOMEN: Minimum possible cipso rule length. |
| 83 | */ |
| 84 | #define SMK_DIGITLEN 4 |
| 85 | #define SMK_CIPSOMIN (SMK_MAXLEN + 2 * SMK_DIGITLEN) |
| 86 | |
| 87 | /* |
| 88 | * Seq_file read operations for /smack/load |
| 89 | */ |
| 90 | |
| 91 | static void *load_seq_start(struct seq_file *s, loff_t *pos) |
| 92 | { |
| 93 | if (*pos == SEQ_READ_FINISHED) |
| 94 | return NULL; |
| 95 | |
| 96 | return smack_list; |
| 97 | } |
| 98 | |
| 99 | static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| 100 | { |
| 101 | struct smk_list_entry *skp = ((struct smk_list_entry *) v)->smk_next; |
| 102 | |
| 103 | if (skp == NULL) |
| 104 | *pos = SEQ_READ_FINISHED; |
| 105 | |
| 106 | return skp; |
| 107 | } |
| 108 | |
| 109 | static int load_seq_show(struct seq_file *s, void *v) |
| 110 | { |
| 111 | struct smk_list_entry *slp = (struct smk_list_entry *) v; |
| 112 | struct smack_rule *srp = &slp->smk_rule; |
| 113 | |
| 114 | seq_printf(s, "%s %s", (char *)srp->smk_subject, |
| 115 | (char *)srp->smk_object); |
| 116 | |
| 117 | seq_putc(s, ' '); |
| 118 | |
| 119 | if (srp->smk_access & MAY_READ) |
| 120 | seq_putc(s, 'r'); |
| 121 | if (srp->smk_access & MAY_WRITE) |
| 122 | seq_putc(s, 'w'); |
| 123 | if (srp->smk_access & MAY_EXEC) |
| 124 | seq_putc(s, 'x'); |
| 125 | if (srp->smk_access & MAY_APPEND) |
| 126 | seq_putc(s, 'a'); |
| 127 | if (srp->smk_access == 0) |
| 128 | seq_putc(s, '-'); |
| 129 | |
| 130 | seq_putc(s, '\n'); |
| 131 | |
| 132 | return 0; |
| 133 | } |
| 134 | |
| 135 | static void load_seq_stop(struct seq_file *s, void *v) |
| 136 | { |
| 137 | /* No-op */ |
| 138 | } |
| 139 | |
| 140 | static struct seq_operations load_seq_ops = { |
| 141 | .start = load_seq_start, |
| 142 | .next = load_seq_next, |
| 143 | .show = load_seq_show, |
| 144 | .stop = load_seq_stop, |
| 145 | }; |
| 146 | |
| 147 | /** |
| 148 | * smk_open_load - open() for /smack/load |
| 149 | * @inode: inode structure representing file |
| 150 | * @file: "load" file pointer |
| 151 | * |
| 152 | * For reading, use load_seq_* seq_file reading operations. |
| 153 | */ |
| 154 | static int smk_open_load(struct inode *inode, struct file *file) |
| 155 | { |
| 156 | if ((file->f_flags & O_ACCMODE) == O_RDONLY) |
| 157 | return seq_open(file, &load_seq_ops); |
| 158 | |
| 159 | if (down_interruptible(&smack_write_sem)) |
| 160 | return -ERESTARTSYS; |
| 161 | |
| 162 | return 0; |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * smk_release_load - release() for /smack/load |
| 167 | * @inode: inode structure representing file |
| 168 | * @file: "load" file pointer |
| 169 | * |
| 170 | * For a reading session, use the seq_file release |
| 171 | * implementation. |
| 172 | * Otherwise, we are at the end of a writing session so |
| 173 | * clean everything up. |
| 174 | */ |
| 175 | static int smk_release_load(struct inode *inode, struct file *file) |
| 176 | { |
| 177 | if ((file->f_flags & O_ACCMODE) == O_RDONLY) |
| 178 | return seq_release(inode, file); |
| 179 | |
| 180 | up(&smack_write_sem); |
| 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | /** |
| 185 | * smk_set_access - add a rule to the rule list |
| 186 | * @srp: the new rule to add |
| 187 | * |
| 188 | * Looks through the current subject/object/access list for |
| 189 | * the subject/object pair and replaces the access that was |
| 190 | * there. If the pair isn't found add it with the specified |
| 191 | * access. |
| 192 | */ |
| 193 | static void smk_set_access(struct smack_rule *srp) |
| 194 | { |
| 195 | struct smk_list_entry *sp; |
| 196 | struct smk_list_entry *newp; |
| 197 | |
| 198 | mutex_lock(&smack_list_lock); |
| 199 | |
| 200 | for (sp = smack_list; sp != NULL; sp = sp->smk_next) |
| 201 | if (sp->smk_rule.smk_subject == srp->smk_subject && |
| 202 | sp->smk_rule.smk_object == srp->smk_object) { |
| 203 | sp->smk_rule.smk_access = srp->smk_access; |
| 204 | break; |
| 205 | } |
| 206 | |
| 207 | if (sp == NULL) { |
| 208 | newp = kzalloc(sizeof(struct smk_list_entry), GFP_KERNEL); |
| 209 | newp->smk_rule = *srp; |
| 210 | newp->smk_next = smack_list; |
| 211 | smack_list = newp; |
| 212 | } |
| 213 | |
| 214 | mutex_unlock(&smack_list_lock); |
| 215 | |
| 216 | return; |
| 217 | } |
| 218 | |
| 219 | /** |
| 220 | * smk_write_load - write() for /smack/load |
| 221 | * @filp: file pointer, not actually used |
| 222 | * @buf: where to get the data from |
| 223 | * @count: bytes sent |
| 224 | * @ppos: where to start - must be 0 |
| 225 | * |
| 226 | * Get one smack access rule from above. |
| 227 | * The format is exactly: |
| 228 | * char subject[SMK_LABELLEN] |
| 229 | * char object[SMK_LABELLEN] |
| 230 | * char access[SMK_ACCESSKINDS] |
| 231 | * |
| 232 | * Anything following is commentary and ignored. |
| 233 | * |
| 234 | * writes must be SMK_LABELLEN+SMK_LABELLEN+4 bytes. |
| 235 | */ |
| 236 | #define MINIMUM_LOAD (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSKINDS) |
| 237 | |
| 238 | static ssize_t smk_write_load(struct file *file, const char __user *buf, |
| 239 | size_t count, loff_t *ppos) |
| 240 | { |
| 241 | struct smack_rule rule; |
| 242 | char *data; |
| 243 | int rc = -EINVAL; |
| 244 | |
| 245 | /* |
| 246 | * Must have privilege. |
| 247 | * No partial writes. |
| 248 | * Enough data must be present. |
| 249 | */ |
| 250 | if (!capable(CAP_MAC_ADMIN)) |
| 251 | return -EPERM; |
| 252 | if (*ppos != 0) |
| 253 | return -EINVAL; |
| 254 | if (count < MINIMUM_LOAD) |
| 255 | return -EINVAL; |
| 256 | |
| 257 | data = kzalloc(count, GFP_KERNEL); |
| 258 | if (data == NULL) |
| 259 | return -ENOMEM; |
| 260 | |
| 261 | if (copy_from_user(data, buf, count) != 0) { |
| 262 | rc = -EFAULT; |
| 263 | goto out; |
| 264 | } |
| 265 | |
| 266 | rule.smk_subject = smk_import(data, 0); |
| 267 | if (rule.smk_subject == NULL) |
| 268 | goto out; |
| 269 | |
| 270 | rule.smk_object = smk_import(data + SMK_LABELLEN, 0); |
| 271 | if (rule.smk_object == NULL) |
| 272 | goto out; |
| 273 | |
| 274 | rule.smk_access = 0; |
| 275 | |
| 276 | switch (data[SMK_LABELLEN + SMK_LABELLEN]) { |
| 277 | case '-': |
| 278 | break; |
| 279 | case 'r': |
| 280 | case 'R': |
| 281 | rule.smk_access |= MAY_READ; |
| 282 | break; |
| 283 | default: |
| 284 | goto out; |
| 285 | } |
| 286 | |
| 287 | switch (data[SMK_LABELLEN + SMK_LABELLEN + 1]) { |
| 288 | case '-': |
| 289 | break; |
| 290 | case 'w': |
| 291 | case 'W': |
| 292 | rule.smk_access |= MAY_WRITE; |
| 293 | break; |
| 294 | default: |
| 295 | goto out; |
| 296 | } |
| 297 | |
| 298 | switch (data[SMK_LABELLEN + SMK_LABELLEN + 2]) { |
| 299 | case '-': |
| 300 | break; |
| 301 | case 'x': |
| 302 | case 'X': |
| 303 | rule.smk_access |= MAY_EXEC; |
| 304 | break; |
| 305 | default: |
| 306 | goto out; |
| 307 | } |
| 308 | |
| 309 | switch (data[SMK_LABELLEN + SMK_LABELLEN + 3]) { |
| 310 | case '-': |
| 311 | break; |
| 312 | case 'a': |
| 313 | case 'A': |
| 314 | rule.smk_access |= MAY_READ; |
| 315 | break; |
| 316 | default: |
| 317 | goto out; |
| 318 | } |
| 319 | |
| 320 | smk_set_access(&rule); |
| 321 | rc = count; |
| 322 | |
| 323 | out: |
| 324 | kfree(data); |
| 325 | return rc; |
| 326 | } |
| 327 | |
| 328 | static const struct file_operations smk_load_ops = { |
| 329 | .open = smk_open_load, |
| 330 | .read = seq_read, |
| 331 | .llseek = seq_lseek, |
| 332 | .write = smk_write_load, |
| 333 | .release = smk_release_load, |
| 334 | }; |
| 335 | |
| 336 | /** |
| 337 | * smk_cipso_doi - initialize the CIPSO domain |
| 338 | */ |
| 339 | void smk_cipso_doi(void) |
| 340 | { |
| 341 | int rc; |
| 342 | struct cipso_v4_doi *doip; |
| 343 | struct netlbl_audit audit_info; |
| 344 | |
| 345 | rc = netlbl_cfg_map_del(NULL, &audit_info); |
| 346 | if (rc != 0) |
| 347 | printk(KERN_WARNING "%s:%d remove rc = %d\n", |
| 348 | __func__, __LINE__, rc); |
| 349 | |
| 350 | doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL); |
| 351 | if (doip == NULL) |
| 352 | panic("smack: Failed to initialize cipso DOI.\n"); |
| 353 | doip->map.std = NULL; |
| 354 | doip->doi = smk_cipso_doi_value; |
| 355 | doip->type = CIPSO_V4_MAP_PASS; |
| 356 | doip->tags[0] = CIPSO_V4_TAG_RBITMAP; |
| 357 | for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++) |
| 358 | doip->tags[rc] = CIPSO_V4_TAG_INVALID; |
| 359 | |
| 360 | rc = netlbl_cfg_cipsov4_add_map(doip, NULL, &audit_info); |
| 361 | if (rc != 0) |
| 362 | printk(KERN_WARNING "%s:%d add rc = %d\n", |
| 363 | __func__, __LINE__, rc); |
| 364 | } |
| 365 | |
| 366 | /* |
| 367 | * Seq_file read operations for /smack/cipso |
| 368 | */ |
| 369 | |
| 370 | static void *cipso_seq_start(struct seq_file *s, loff_t *pos) |
| 371 | { |
| 372 | if (*pos == SEQ_READ_FINISHED) |
| 373 | return NULL; |
| 374 | |
| 375 | return smack_known; |
| 376 | } |
| 377 | |
| 378 | static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos) |
| 379 | { |
| 380 | struct smack_known *skp = ((struct smack_known *) v)->smk_next; |
| 381 | |
| 382 | /* |
| 383 | * Omit labels with no associated cipso value |
| 384 | */ |
| 385 | while (skp != NULL && !skp->smk_cipso) |
| 386 | skp = skp->smk_next; |
| 387 | |
| 388 | if (skp == NULL) |
| 389 | *pos = SEQ_READ_FINISHED; |
| 390 | |
| 391 | return skp; |
| 392 | } |
| 393 | |
| 394 | /* |
| 395 | * Print cipso labels in format: |
| 396 | * label level[/cat[,cat]] |
| 397 | */ |
| 398 | static int cipso_seq_show(struct seq_file *s, void *v) |
| 399 | { |
| 400 | struct smack_known *skp = (struct smack_known *) v; |
| 401 | struct smack_cipso *scp = skp->smk_cipso; |
| 402 | char *cbp; |
| 403 | char sep = '/'; |
| 404 | int cat = 1; |
| 405 | int i; |
| 406 | unsigned char m; |
| 407 | |
| 408 | if (scp == NULL) |
| 409 | return 0; |
| 410 | |
| 411 | seq_printf(s, "%s %3d", (char *)&skp->smk_known, scp->smk_level); |
| 412 | |
| 413 | cbp = scp->smk_catset; |
| 414 | for (i = 0; i < SMK_LABELLEN; i++) |
| 415 | for (m = 0x80; m != 0; m >>= 1) { |
| 416 | if (m & cbp[i]) { |
| 417 | seq_printf(s, "%c%d", sep, cat); |
| 418 | sep = ','; |
| 419 | } |
| 420 | cat++; |
| 421 | } |
| 422 | |
| 423 | seq_putc(s, '\n'); |
| 424 | |
| 425 | return 0; |
| 426 | } |
| 427 | |
| 428 | static void cipso_seq_stop(struct seq_file *s, void *v) |
| 429 | { |
| 430 | /* No-op */ |
| 431 | } |
| 432 | |
| 433 | static struct seq_operations cipso_seq_ops = { |
| 434 | .start = cipso_seq_start, |
| 435 | .stop = cipso_seq_stop, |
| 436 | .next = cipso_seq_next, |
| 437 | .show = cipso_seq_show, |
| 438 | }; |
| 439 | |
| 440 | /** |
| 441 | * smk_open_cipso - open() for /smack/cipso |
| 442 | * @inode: inode structure representing file |
| 443 | * @file: "cipso" file pointer |
| 444 | * |
| 445 | * Connect our cipso_seq_* operations with /smack/cipso |
| 446 | * file_operations |
| 447 | */ |
| 448 | static int smk_open_cipso(struct inode *inode, struct file *file) |
| 449 | { |
| 450 | return seq_open(file, &cipso_seq_ops); |
| 451 | } |
| 452 | |
| 453 | /** |
| 454 | * smk_write_cipso - write() for /smack/cipso |
| 455 | * @filp: file pointer, not actually used |
| 456 | * @buf: where to get the data from |
| 457 | * @count: bytes sent |
| 458 | * @ppos: where to start |
| 459 | * |
| 460 | * Accepts only one cipso rule per write call. |
| 461 | * Returns number of bytes written or error code, as appropriate |
| 462 | */ |
| 463 | static ssize_t smk_write_cipso(struct file *file, const char __user *buf, |
| 464 | size_t count, loff_t *ppos) |
| 465 | { |
| 466 | struct smack_known *skp; |
| 467 | struct smack_cipso *scp = NULL; |
| 468 | char mapcatset[SMK_LABELLEN]; |
| 469 | int maplevel; |
| 470 | int cat; |
| 471 | int catlen; |
| 472 | ssize_t rc = -EINVAL; |
| 473 | char *data = NULL; |
| 474 | char *rule; |
| 475 | int ret; |
| 476 | int i; |
| 477 | |
| 478 | /* |
| 479 | * Must have privilege. |
| 480 | * No partial writes. |
| 481 | * Enough data must be present. |
| 482 | */ |
| 483 | if (!capable(CAP_MAC_ADMIN)) |
| 484 | return -EPERM; |
| 485 | if (*ppos != 0) |
| 486 | return -EINVAL; |
| 487 | if (count <= SMK_CIPSOMIN) |
| 488 | return -EINVAL; |
| 489 | |
| 490 | data = kzalloc(count + 1, GFP_KERNEL); |
| 491 | if (data == NULL) |
| 492 | return -ENOMEM; |
| 493 | |
| 494 | if (copy_from_user(data, buf, count) != 0) { |
| 495 | rc = -EFAULT; |
| 496 | goto unlockedout; |
| 497 | } |
| 498 | |
| 499 | data[count] = '\0'; |
| 500 | rule = data; |
| 501 | /* |
| 502 | * Only allow one writer at a time. Writes should be |
| 503 | * quite rare and small in any case. |
| 504 | */ |
| 505 | mutex_lock(&smack_cipso_lock); |
| 506 | |
| 507 | skp = smk_import_entry(rule, 0); |
| 508 | if (skp == NULL) |
| 509 | goto out; |
| 510 | |
| 511 | rule += SMK_LABELLEN;; |
| 512 | ret = sscanf(rule, "%d", &maplevel); |
| 513 | if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL) |
| 514 | goto out; |
| 515 | |
| 516 | rule += SMK_DIGITLEN; |
| 517 | ret = sscanf(rule, "%d", &catlen); |
| 518 | if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM) |
| 519 | goto out; |
| 520 | |
| 521 | if (count <= (SMK_CIPSOMIN + catlen * SMK_DIGITLEN)) |
| 522 | goto out; |
| 523 | |
| 524 | memset(mapcatset, 0, sizeof(mapcatset)); |
| 525 | |
| 526 | for (i = 0; i < catlen; i++) { |
| 527 | rule += SMK_DIGITLEN; |
| 528 | ret = sscanf(rule, "%d", &cat); |
| 529 | if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL) |
| 530 | goto out; |
| 531 | |
| 532 | smack_catset_bit(cat, mapcatset); |
| 533 | } |
| 534 | |
| 535 | if (skp->smk_cipso == NULL) { |
| 536 | scp = kzalloc(sizeof(struct smack_cipso), GFP_KERNEL); |
| 537 | if (scp == NULL) { |
| 538 | rc = -ENOMEM; |
| 539 | goto out; |
| 540 | } |
| 541 | } |
| 542 | |
| 543 | spin_lock_bh(&skp->smk_cipsolock); |
| 544 | |
| 545 | if (scp == NULL) |
| 546 | scp = skp->smk_cipso; |
| 547 | else |
| 548 | skp->smk_cipso = scp; |
| 549 | |
| 550 | scp->smk_level = maplevel; |
| 551 | memcpy(scp->smk_catset, mapcatset, sizeof(mapcatset)); |
| 552 | |
| 553 | spin_unlock_bh(&skp->smk_cipsolock); |
| 554 | |
| 555 | rc = count; |
| 556 | out: |
| 557 | mutex_unlock(&smack_cipso_lock); |
| 558 | unlockedout: |
| 559 | kfree(data); |
| 560 | return rc; |
| 561 | } |
| 562 | |
| 563 | static const struct file_operations smk_cipso_ops = { |
| 564 | .open = smk_open_cipso, |
| 565 | .read = seq_read, |
| 566 | .llseek = seq_lseek, |
| 567 | .write = smk_write_cipso, |
| 568 | .release = seq_release, |
| 569 | }; |
| 570 | |
| 571 | /** |
| 572 | * smk_read_doi - read() for /smack/doi |
| 573 | * @filp: file pointer, not actually used |
| 574 | * @buf: where to put the result |
| 575 | * @count: maximum to send along |
| 576 | * @ppos: where to start |
| 577 | * |
| 578 | * Returns number of bytes read or error code, as appropriate |
| 579 | */ |
| 580 | static ssize_t smk_read_doi(struct file *filp, char __user *buf, |
| 581 | size_t count, loff_t *ppos) |
| 582 | { |
| 583 | char temp[80]; |
| 584 | ssize_t rc; |
| 585 | |
| 586 | if (*ppos != 0) |
| 587 | return 0; |
| 588 | |
| 589 | sprintf(temp, "%d", smk_cipso_doi_value); |
| 590 | rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); |
| 591 | |
| 592 | return rc; |
| 593 | } |
| 594 | |
| 595 | /** |
| 596 | * smk_write_doi - write() for /smack/doi |
| 597 | * @filp: file pointer, not actually used |
| 598 | * @buf: where to get the data from |
| 599 | * @count: bytes sent |
| 600 | * @ppos: where to start |
| 601 | * |
| 602 | * Returns number of bytes written or error code, as appropriate |
| 603 | */ |
| 604 | static ssize_t smk_write_doi(struct file *file, const char __user *buf, |
| 605 | size_t count, loff_t *ppos) |
| 606 | { |
| 607 | char temp[80]; |
| 608 | int i; |
| 609 | |
| 610 | if (!capable(CAP_MAC_ADMIN)) |
| 611 | return -EPERM; |
| 612 | |
| 613 | if (count >= sizeof(temp) || count == 0) |
| 614 | return -EINVAL; |
| 615 | |
| 616 | if (copy_from_user(temp, buf, count) != 0) |
| 617 | return -EFAULT; |
| 618 | |
| 619 | temp[count] = '\0'; |
| 620 | |
| 621 | if (sscanf(temp, "%d", &i) != 1) |
| 622 | return -EINVAL; |
| 623 | |
| 624 | smk_cipso_doi_value = i; |
| 625 | |
| 626 | smk_cipso_doi(); |
| 627 | |
| 628 | return count; |
| 629 | } |
| 630 | |
| 631 | static const struct file_operations smk_doi_ops = { |
| 632 | .read = smk_read_doi, |
| 633 | .write = smk_write_doi, |
| 634 | }; |
| 635 | |
| 636 | /** |
| 637 | * smk_read_direct - read() for /smack/direct |
| 638 | * @filp: file pointer, not actually used |
| 639 | * @buf: where to put the result |
| 640 | * @count: maximum to send along |
| 641 | * @ppos: where to start |
| 642 | * |
| 643 | * Returns number of bytes read or error code, as appropriate |
| 644 | */ |
| 645 | static ssize_t smk_read_direct(struct file *filp, char __user *buf, |
| 646 | size_t count, loff_t *ppos) |
| 647 | { |
| 648 | char temp[80]; |
| 649 | ssize_t rc; |
| 650 | |
| 651 | if (*ppos != 0) |
| 652 | return 0; |
| 653 | |
| 654 | sprintf(temp, "%d", smack_cipso_direct); |
| 655 | rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp)); |
| 656 | |
| 657 | return rc; |
| 658 | } |
| 659 | |
| 660 | /** |
| 661 | * smk_write_direct - write() for /smack/direct |
| 662 | * @filp: file pointer, not actually used |
| 663 | * @buf: where to get the data from |
| 664 | * @count: bytes sent |
| 665 | * @ppos: where to start |
| 666 | * |
| 667 | * Returns number of bytes written or error code, as appropriate |
| 668 | */ |
| 669 | static ssize_t smk_write_direct(struct file *file, const char __user *buf, |
| 670 | size_t count, loff_t *ppos) |
| 671 | { |
| 672 | char temp[80]; |
| 673 | int i; |
| 674 | |
| 675 | if (!capable(CAP_MAC_ADMIN)) |
| 676 | return -EPERM; |
| 677 | |
| 678 | if (count >= sizeof(temp) || count == 0) |
| 679 | return -EINVAL; |
| 680 | |
| 681 | if (copy_from_user(temp, buf, count) != 0) |
| 682 | return -EFAULT; |
| 683 | |
| 684 | temp[count] = '\0'; |
| 685 | |
| 686 | if (sscanf(temp, "%d", &i) != 1) |
| 687 | return -EINVAL; |
| 688 | |
| 689 | smack_cipso_direct = i; |
| 690 | |
| 691 | return count; |
| 692 | } |
| 693 | |
| 694 | static const struct file_operations smk_direct_ops = { |
| 695 | .read = smk_read_direct, |
| 696 | .write = smk_write_direct, |
| 697 | }; |
| 698 | |
| 699 | /** |
| 700 | * smk_read_ambient - read() for /smack/ambient |
| 701 | * @filp: file pointer, not actually used |
| 702 | * @buf: where to put the result |
| 703 | * @cn: maximum to send along |
| 704 | * @ppos: where to start |
| 705 | * |
| 706 | * Returns number of bytes read or error code, as appropriate |
| 707 | */ |
| 708 | static ssize_t smk_read_ambient(struct file *filp, char __user *buf, |
| 709 | size_t cn, loff_t *ppos) |
| 710 | { |
| 711 | ssize_t rc; |
| 712 | char out[SMK_LABELLEN]; |
| 713 | int asize; |
| 714 | |
| 715 | if (*ppos != 0) |
| 716 | return 0; |
| 717 | /* |
| 718 | * Being careful to avoid a problem in the case where |
| 719 | * smack_net_ambient gets changed in midstream. |
| 720 | * Since smack_net_ambient is always set with a value |
| 721 | * from the label list, including initially, and those |
| 722 | * never get freed, the worst case is that the pointer |
| 723 | * gets changed just after this strncpy, in which case |
| 724 | * the value passed up is incorrect. Locking around |
| 725 | * smack_net_ambient wouldn't be any better than this |
| 726 | * copy scheme as by the time the caller got to look |
| 727 | * at the ambient value it would have cleared the lock |
| 728 | * and been changed. |
| 729 | */ |
| 730 | strncpy(out, smack_net_ambient, SMK_LABELLEN); |
| 731 | asize = strlen(out) + 1; |
| 732 | |
| 733 | if (cn < asize) |
| 734 | return -EINVAL; |
| 735 | |
| 736 | rc = simple_read_from_buffer(buf, cn, ppos, out, asize); |
| 737 | |
| 738 | return rc; |
| 739 | } |
| 740 | |
| 741 | /** |
| 742 | * smk_write_ambient - write() for /smack/ambient |
| 743 | * @filp: file pointer, not actually used |
| 744 | * @buf: where to get the data from |
| 745 | * @count: bytes sent |
| 746 | * @ppos: where to start |
| 747 | * |
| 748 | * Returns number of bytes written or error code, as appropriate |
| 749 | */ |
| 750 | static ssize_t smk_write_ambient(struct file *file, const char __user *buf, |
| 751 | size_t count, loff_t *ppos) |
| 752 | { |
| 753 | char in[SMK_LABELLEN]; |
| 754 | char *smack; |
| 755 | |
| 756 | if (!capable(CAP_MAC_ADMIN)) |
| 757 | return -EPERM; |
| 758 | |
| 759 | if (count >= SMK_LABELLEN) |
| 760 | return -EINVAL; |
| 761 | |
| 762 | if (copy_from_user(in, buf, count) != 0) |
| 763 | return -EFAULT; |
| 764 | |
| 765 | smack = smk_import(in, count); |
| 766 | if (smack == NULL) |
| 767 | return -EINVAL; |
| 768 | |
| 769 | smack_net_ambient = smack; |
| 770 | |
| 771 | return count; |
| 772 | } |
| 773 | |
| 774 | static const struct file_operations smk_ambient_ops = { |
| 775 | .read = smk_read_ambient, |
| 776 | .write = smk_write_ambient, |
| 777 | }; |
| 778 | |
| 779 | struct option_names { |
| 780 | int o_number; |
| 781 | char *o_name; |
| 782 | char *o_alias; |
| 783 | }; |
| 784 | |
| 785 | static struct option_names netlbl_choices[] = { |
| 786 | { NETLBL_NLTYPE_RIPSO, |
| 787 | NETLBL_NLTYPE_RIPSO_NAME, "ripso" }, |
| 788 | { NETLBL_NLTYPE_CIPSOV4, |
| 789 | NETLBL_NLTYPE_CIPSOV4_NAME, "cipsov4" }, |
| 790 | { NETLBL_NLTYPE_CIPSOV4, |
| 791 | NETLBL_NLTYPE_CIPSOV4_NAME, "cipso" }, |
| 792 | { NETLBL_NLTYPE_CIPSOV6, |
| 793 | NETLBL_NLTYPE_CIPSOV6_NAME, "cipsov6" }, |
| 794 | { NETLBL_NLTYPE_UNLABELED, |
| 795 | NETLBL_NLTYPE_UNLABELED_NAME, "unlabeled" }, |
| 796 | }; |
| 797 | |
| 798 | /** |
| 799 | * smk_read_nltype - read() for /smack/nltype |
| 800 | * @filp: file pointer, not actually used |
| 801 | * @buf: where to put the result |
| 802 | * @count: maximum to send along |
| 803 | * @ppos: where to start |
| 804 | * |
| 805 | * Returns number of bytes read or error code, as appropriate |
| 806 | */ |
| 807 | static ssize_t smk_read_nltype(struct file *filp, char __user *buf, |
| 808 | size_t count, loff_t *ppos) |
| 809 | { |
| 810 | char bound[40]; |
| 811 | ssize_t rc; |
| 812 | int i; |
| 813 | |
| 814 | if (count < SMK_LABELLEN) |
| 815 | return -EINVAL; |
| 816 | |
| 817 | if (*ppos != 0) |
| 818 | return 0; |
| 819 | |
| 820 | sprintf(bound, "unknown"); |
| 821 | |
| 822 | for (i = 0; i < ARRAY_SIZE(netlbl_choices); i++) |
| 823 | if (smack_net_nltype == netlbl_choices[i].o_number) { |
| 824 | sprintf(bound, "%s", netlbl_choices[i].o_name); |
| 825 | break; |
| 826 | } |
| 827 | |
| 828 | rc = simple_read_from_buffer(buf, count, ppos, bound, strlen(bound)); |
| 829 | |
| 830 | return rc; |
| 831 | } |
| 832 | |
| 833 | /** |
| 834 | * smk_write_nltype - write() for /smack/nltype |
| 835 | * @filp: file pointer, not actually used |
| 836 | * @buf: where to get the data from |
| 837 | * @count: bytes sent |
| 838 | * @ppos: where to start |
| 839 | * |
| 840 | * Returns number of bytes written or error code, as appropriate |
| 841 | */ |
| 842 | static ssize_t smk_write_nltype(struct file *file, const char __user *buf, |
| 843 | size_t count, loff_t *ppos) |
| 844 | { |
| 845 | char bound[40]; |
| 846 | char *cp; |
| 847 | int i; |
| 848 | |
| 849 | if (!capable(CAP_MAC_ADMIN)) |
| 850 | return -EPERM; |
| 851 | |
| 852 | if (count >= 40) |
| 853 | return -EINVAL; |
| 854 | |
| 855 | if (copy_from_user(bound, buf, count) != 0) |
| 856 | return -EFAULT; |
| 857 | |
| 858 | bound[count] = '\0'; |
| 859 | cp = strchr(bound, ' '); |
| 860 | if (cp != NULL) |
| 861 | *cp = '\0'; |
| 862 | cp = strchr(bound, '\n'); |
| 863 | if (cp != NULL) |
| 864 | *cp = '\0'; |
| 865 | |
| 866 | for (i = 0; i < ARRAY_SIZE(netlbl_choices); i++) |
| 867 | if (strcmp(bound, netlbl_choices[i].o_name) == 0 || |
| 868 | strcmp(bound, netlbl_choices[i].o_alias) == 0) { |
| 869 | smack_net_nltype = netlbl_choices[i].o_number; |
| 870 | return count; |
| 871 | } |
| 872 | /* |
| 873 | * Not a valid choice. |
| 874 | */ |
| 875 | return -EINVAL; |
| 876 | } |
| 877 | |
| 878 | static const struct file_operations smk_nltype_ops = { |
| 879 | .read = smk_read_nltype, |
| 880 | .write = smk_write_nltype, |
| 881 | }; |
| 882 | |
| 883 | /** |
| 884 | * smk_fill_super - fill the /smackfs superblock |
| 885 | * @sb: the empty superblock |
| 886 | * @data: unused |
| 887 | * @silent: unused |
| 888 | * |
| 889 | * Fill in the well known entries for /smack |
| 890 | * |
| 891 | * Returns 0 on success, an error code on failure |
| 892 | */ |
| 893 | static int smk_fill_super(struct super_block *sb, void *data, int silent) |
| 894 | { |
| 895 | int rc; |
| 896 | struct inode *root_inode; |
| 897 | |
| 898 | static struct tree_descr smack_files[] = { |
| 899 | [SMK_LOAD] = |
| 900 | {"load", &smk_load_ops, S_IRUGO|S_IWUSR}, |
| 901 | [SMK_CIPSO] = |
| 902 | {"cipso", &smk_cipso_ops, S_IRUGO|S_IWUSR}, |
| 903 | [SMK_DOI] = |
| 904 | {"doi", &smk_doi_ops, S_IRUGO|S_IWUSR}, |
| 905 | [SMK_DIRECT] = |
| 906 | {"direct", &smk_direct_ops, S_IRUGO|S_IWUSR}, |
| 907 | [SMK_AMBIENT] = |
| 908 | {"ambient", &smk_ambient_ops, S_IRUGO|S_IWUSR}, |
| 909 | [SMK_NLTYPE] = |
| 910 | {"nltype", &smk_nltype_ops, S_IRUGO|S_IWUSR}, |
| 911 | /* last one */ {""} |
| 912 | }; |
| 913 | |
| 914 | rc = simple_fill_super(sb, SMACK_MAGIC, smack_files); |
| 915 | if (rc != 0) { |
| 916 | printk(KERN_ERR "%s failed %d while creating inodes\n", |
| 917 | __func__, rc); |
| 918 | return rc; |
| 919 | } |
| 920 | |
| 921 | root_inode = sb->s_root->d_inode; |
| 922 | root_inode->i_security = new_inode_smack(smack_known_floor.smk_known); |
| 923 | |
| 924 | return 0; |
| 925 | } |
| 926 | |
| 927 | /** |
| 928 | * smk_get_sb - get the smackfs superblock |
| 929 | * @fs_type: passed along without comment |
| 930 | * @flags: passed along without comment |
| 931 | * @dev_name: passed along without comment |
| 932 | * @data: passed along without comment |
| 933 | * @mnt: passed along without comment |
| 934 | * |
| 935 | * Just passes everything along. |
| 936 | * |
| 937 | * Returns what the lower level code does. |
| 938 | */ |
| 939 | static int smk_get_sb(struct file_system_type *fs_type, |
| 940 | int flags, const char *dev_name, void *data, |
| 941 | struct vfsmount *mnt) |
| 942 | { |
| 943 | return get_sb_single(fs_type, flags, data, smk_fill_super, mnt); |
| 944 | } |
| 945 | |
| 946 | static struct file_system_type smk_fs_type = { |
| 947 | .name = "smackfs", |
| 948 | .get_sb = smk_get_sb, |
| 949 | .kill_sb = kill_litter_super, |
| 950 | }; |
| 951 | |
| 952 | static struct vfsmount *smackfs_mount; |
| 953 | |
| 954 | /** |
| 955 | * init_smk_fs - get the smackfs superblock |
| 956 | * |
| 957 | * register the smackfs |
| 958 | * |
| 959 | * Returns 0 unless the registration fails. |
| 960 | */ |
| 961 | static int __init init_smk_fs(void) |
| 962 | { |
| 963 | int err; |
| 964 | |
| 965 | err = register_filesystem(&smk_fs_type); |
| 966 | if (!err) { |
| 967 | smackfs_mount = kern_mount(&smk_fs_type); |
| 968 | if (IS_ERR(smackfs_mount)) { |
| 969 | printk(KERN_ERR "smackfs: could not mount!\n"); |
| 970 | err = PTR_ERR(smackfs_mount); |
| 971 | smackfs_mount = NULL; |
| 972 | } |
| 973 | } |
| 974 | |
| 975 | sema_init(&smack_write_sem, 1); |
| 976 | smk_cipso_doi(); |
| 977 | |
| 978 | return err; |
| 979 | } |
| 980 | |
| 981 | __initcall(init_smk_fs); |