1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Simplified MAC Kernel (smack) security module 4 * 5 * This file contains the smack hook function implementations. 6 * 7 * Authors: 8 * Casey Schaufler <casey@schaufler-ca.com> 9 * Jarkko Sakkinen <jarkko.sakkinen@intel.com> 10 * 11 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> 12 * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. 13 * Paul Moore <paul@paul-moore.com> 14 * Copyright (C) 2010 Nokia Corporation 15 * Copyright (C) 2011 Intel Corporation. 16 */ 17 18 #include <linux/xattr.h> 19 #include <linux/pagemap.h> 20 #include <linux/mount.h> 21 #include <linux/stat.h> 22 #include <linux/kd.h> 23 #include <asm/ioctls.h> 24 #include <linux/ip.h> 25 #include <linux/tcp.h> 26 #include <linux/udp.h> 27 #include <linux/dccp.h> 28 #include <linux/icmpv6.h> 29 #include <linux/slab.h> 30 #include <linux/mutex.h> 31 #include <net/cipso_ipv4.h> 32 #include <net/ip.h> 33 #include <net/ipv6.h> 34 #include <linux/audit.h> 35 #include <linux/magic.h> 36 #include <linux/dcache.h> 37 #include <linux/personality.h> 38 #include <linux/msg.h> 39 #include <linux/shm.h> 40 #include <linux/binfmts.h> 41 #include <linux/parser.h> 42 #include <linux/fs_context.h> 43 #include <linux/fs_parser.h> 44 #include <linux/watch_queue.h> 45 #include <linux/io_uring.h> 46 #include "smack.h" 47 48 #define TRANS_TRUE "TRUE" 49 #define TRANS_TRUE_SIZE 4 50 51 #define SMK_CONNECTING 0 52 #define SMK_RECEIVING 1 53 #define SMK_SENDING 2 54 55 #ifdef SMACK_IPV6_PORT_LABELING 56 static DEFINE_MUTEX(smack_ipv6_lock); 57 static LIST_HEAD(smk_ipv6_port_list); 58 #endif 59 struct kmem_cache *smack_rule_cache; 60 int smack_enabled __initdata; 61 62 #define A(s) {"smack"#s, sizeof("smack"#s) - 1, Opt_##s} 63 static struct { 64 const char *name; 65 int len; 66 int opt; 67 } smk_mount_opts[] = { 68 {"smackfsdef", sizeof("smackfsdef") - 1, Opt_fsdefault}, 69 A(fsdefault), A(fsfloor), A(fshat), A(fsroot), A(fstransmute) 70 }; 71 #undef A 72 73 static int match_opt_prefix(char *s, int l, char **arg) 74 { 75 int i; 76 77 for (i = 0; i < ARRAY_SIZE(smk_mount_opts); i++) { 78 size_t len = smk_mount_opts[i].len; 79 if (len > l || memcmp(s, smk_mount_opts[i].name, len)) 80 continue; 81 if (len == l || s[len] != '=') 82 continue; 83 *arg = s + len + 1; 84 return smk_mount_opts[i].opt; 85 } 86 return Opt_error; 87 } 88 89 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 90 static char *smk_bu_mess[] = { 91 "Bringup Error", /* Unused */ 92 "Bringup", /* SMACK_BRINGUP_ALLOW */ 93 "Unconfined Subject", /* SMACK_UNCONFINED_SUBJECT */ 94 "Unconfined Object", /* SMACK_UNCONFINED_OBJECT */ 95 }; 96 97 static void smk_bu_mode(int mode, char *s) 98 { 99 int i = 0; 100 101 if (mode & MAY_READ) 102 s[i++] = 'r'; 103 if (mode & MAY_WRITE) 104 s[i++] = 'w'; 105 if (mode & MAY_EXEC) 106 s[i++] = 'x'; 107 if (mode & MAY_APPEND) 108 s[i++] = 'a'; 109 if (mode & MAY_TRANSMUTE) 110 s[i++] = 't'; 111 if (mode & MAY_LOCK) 112 s[i++] = 'l'; 113 if (i == 0) 114 s[i++] = '-'; 115 s[i] = '\0'; 116 } 117 #endif 118 119 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 120 static int smk_bu_note(char *note, struct smack_known *sskp, 121 struct smack_known *oskp, int mode, int rc) 122 { 123 char acc[SMK_NUM_ACCESS_TYPE + 1]; 124 125 if (rc <= 0) 126 return rc; 127 if (rc > SMACK_UNCONFINED_OBJECT) 128 rc = 0; 129 130 smk_bu_mode(mode, acc); 131 pr_info("Smack %s: (%s %s %s) %s\n", smk_bu_mess[rc], 132 sskp->smk_known, oskp->smk_known, acc, note); 133 return 0; 134 } 135 #else 136 #define smk_bu_note(note, sskp, oskp, mode, RC) (RC) 137 #endif 138 139 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 140 static int smk_bu_current(char *note, struct smack_known *oskp, 141 int mode, int rc) 142 { 143 struct task_smack *tsp = smack_cred(current_cred()); 144 char acc[SMK_NUM_ACCESS_TYPE + 1]; 145 146 if (rc <= 0) 147 return rc; 148 if (rc > SMACK_UNCONFINED_OBJECT) 149 rc = 0; 150 151 smk_bu_mode(mode, acc); 152 pr_info("Smack %s: (%s %s %s) %s %s\n", smk_bu_mess[rc], 153 tsp->smk_task->smk_known, oskp->smk_known, 154 acc, current->comm, note); 155 return 0; 156 } 157 #else 158 #define smk_bu_current(note, oskp, mode, RC) (RC) 159 #endif 160 161 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 162 static int smk_bu_task(struct task_struct *otp, int mode, int rc) 163 { 164 struct task_smack *tsp = smack_cred(current_cred()); 165 struct smack_known *smk_task = smk_of_task_struct_obj(otp); 166 char acc[SMK_NUM_ACCESS_TYPE + 1]; 167 168 if (rc <= 0) 169 return rc; 170 if (rc > SMACK_UNCONFINED_OBJECT) 171 rc = 0; 172 173 smk_bu_mode(mode, acc); 174 pr_info("Smack %s: (%s %s %s) %s to %s\n", smk_bu_mess[rc], 175 tsp->smk_task->smk_known, smk_task->smk_known, acc, 176 current->comm, otp->comm); 177 return 0; 178 } 179 #else 180 #define smk_bu_task(otp, mode, RC) (RC) 181 #endif 182 183 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 184 static int smk_bu_inode(struct inode *inode, int mode, int rc) 185 { 186 struct task_smack *tsp = smack_cred(current_cred()); 187 struct inode_smack *isp = smack_inode(inode); 188 char acc[SMK_NUM_ACCESS_TYPE + 1]; 189 190 if (isp->smk_flags & SMK_INODE_IMPURE) 191 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", 192 inode->i_sb->s_id, inode->i_ino, current->comm); 193 194 if (rc <= 0) 195 return rc; 196 if (rc > SMACK_UNCONFINED_OBJECT) 197 rc = 0; 198 if (rc == SMACK_UNCONFINED_SUBJECT && 199 (mode & (MAY_WRITE | MAY_APPEND))) 200 isp->smk_flags |= SMK_INODE_IMPURE; 201 202 smk_bu_mode(mode, acc); 203 204 pr_info("Smack %s: (%s %s %s) inode=(%s %ld) %s\n", smk_bu_mess[rc], 205 tsp->smk_task->smk_known, isp->smk_inode->smk_known, acc, 206 inode->i_sb->s_id, inode->i_ino, current->comm); 207 return 0; 208 } 209 #else 210 #define smk_bu_inode(inode, mode, RC) (RC) 211 #endif 212 213 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 214 static int smk_bu_file(struct file *file, int mode, int rc) 215 { 216 struct task_smack *tsp = smack_cred(current_cred()); 217 struct smack_known *sskp = tsp->smk_task; 218 struct inode *inode = file_inode(file); 219 struct inode_smack *isp = smack_inode(inode); 220 char acc[SMK_NUM_ACCESS_TYPE + 1]; 221 222 if (isp->smk_flags & SMK_INODE_IMPURE) 223 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", 224 inode->i_sb->s_id, inode->i_ino, current->comm); 225 226 if (rc <= 0) 227 return rc; 228 if (rc > SMACK_UNCONFINED_OBJECT) 229 rc = 0; 230 231 smk_bu_mode(mode, acc); 232 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc], 233 sskp->smk_known, smk_of_inode(inode)->smk_known, acc, 234 inode->i_sb->s_id, inode->i_ino, file, 235 current->comm); 236 return 0; 237 } 238 #else 239 #define smk_bu_file(file, mode, RC) (RC) 240 #endif 241 242 #ifdef CONFIG_SECURITY_SMACK_BRINGUP 243 static int smk_bu_credfile(const struct cred *cred, struct file *file, 244 int mode, int rc) 245 { 246 struct task_smack *tsp = smack_cred(cred); 247 struct smack_known *sskp = tsp->smk_task; 248 struct inode *inode = file_inode(file); 249 struct inode_smack *isp = smack_inode(inode); 250 char acc[SMK_NUM_ACCESS_TYPE + 1]; 251 252 if (isp->smk_flags & SMK_INODE_IMPURE) 253 pr_info("Smack Unconfined Corruption: inode=(%s %ld) %s\n", 254 inode->i_sb->s_id, inode->i_ino, current->comm); 255 256 if (rc <= 0) 257 return rc; 258 if (rc > SMACK_UNCONFINED_OBJECT) 259 rc = 0; 260 261 smk_bu_mode(mode, acc); 262 pr_info("Smack %s: (%s %s %s) file=(%s %ld %pD) %s\n", smk_bu_mess[rc], 263 sskp->smk_known, smk_of_inode(inode)->smk_known, acc, 264 inode->i_sb->s_id, inode->i_ino, file, 265 current->comm); 266 return 0; 267 } 268 #else 269 #define smk_bu_credfile(cred, file, mode, RC) (RC) 270 #endif 271 272 /** 273 * smk_fetch - Fetch the smack label from a file. 274 * @name: type of the label (attribute) 275 * @ip: a pointer to the inode 276 * @dp: a pointer to the dentry 277 * 278 * Returns a pointer to the master list entry for the Smack label, 279 * NULL if there was no label to fetch, or an error code. 280 */ 281 static struct smack_known *smk_fetch(const char *name, struct inode *ip, 282 struct dentry *dp) 283 { 284 int rc; 285 char *buffer; 286 struct smack_known *skp = NULL; 287 288 if (!(ip->i_opflags & IOP_XATTR)) 289 return ERR_PTR(-EOPNOTSUPP); 290 291 buffer = kzalloc(SMK_LONGLABEL, GFP_NOFS); 292 if (buffer == NULL) 293 return ERR_PTR(-ENOMEM); 294 295 rc = __vfs_getxattr(dp, ip, name, buffer, SMK_LONGLABEL); 296 if (rc < 0) 297 skp = ERR_PTR(rc); 298 else if (rc == 0) 299 skp = NULL; 300 else 301 skp = smk_import_entry(buffer, rc); 302 303 kfree(buffer); 304 305 return skp; 306 } 307 308 /** 309 * init_inode_smack - initialize an inode security blob 310 * @inode: inode to extract the info from 311 * @skp: a pointer to the Smack label entry to use in the blob 312 * 313 */ 314 static void init_inode_smack(struct inode *inode, struct smack_known *skp) 315 { 316 struct inode_smack *isp = smack_inode(inode); 317 318 isp->smk_inode = skp; 319 isp->smk_flags = 0; 320 } 321 322 /** 323 * init_task_smack - initialize a task security blob 324 * @tsp: blob to initialize 325 * @task: a pointer to the Smack label for the running task 326 * @forked: a pointer to the Smack label for the forked task 327 * 328 */ 329 static void init_task_smack(struct task_smack *tsp, struct smack_known *task, 330 struct smack_known *forked) 331 { 332 tsp->smk_task = task; 333 tsp->smk_forked = forked; 334 INIT_LIST_HEAD(&tsp->smk_rules); 335 INIT_LIST_HEAD(&tsp->smk_relabel); 336 mutex_init(&tsp->smk_rules_lock); 337 } 338 339 /** 340 * smk_copy_rules - copy a rule set 341 * @nhead: new rules header pointer 342 * @ohead: old rules header pointer 343 * @gfp: type of the memory for the allocation 344 * 345 * Returns 0 on success, -ENOMEM on error 346 */ 347 static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead, 348 gfp_t gfp) 349 { 350 struct smack_rule *nrp; 351 struct smack_rule *orp; 352 int rc = 0; 353 354 list_for_each_entry_rcu(orp, ohead, list) { 355 nrp = kmem_cache_zalloc(smack_rule_cache, gfp); 356 if (nrp == NULL) { 357 rc = -ENOMEM; 358 break; 359 } 360 *nrp = *orp; 361 list_add_rcu(&nrp->list, nhead); 362 } 363 return rc; 364 } 365 366 /** 367 * smk_copy_relabel - copy smk_relabel labels list 368 * @nhead: new rules header pointer 369 * @ohead: old rules header pointer 370 * @gfp: type of the memory for the allocation 371 * 372 * Returns 0 on success, -ENOMEM on error 373 */ 374 static int smk_copy_relabel(struct list_head *nhead, struct list_head *ohead, 375 gfp_t gfp) 376 { 377 struct smack_known_list_elem *nklep; 378 struct smack_known_list_elem *oklep; 379 380 list_for_each_entry(oklep, ohead, list) { 381 nklep = kzalloc(sizeof(struct smack_known_list_elem), gfp); 382 if (nklep == NULL) { 383 smk_destroy_label_list(nhead); 384 return -ENOMEM; 385 } 386 nklep->smk_label = oklep->smk_label; 387 list_add(&nklep->list, nhead); 388 } 389 390 return 0; 391 } 392 393 /** 394 * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_* 395 * @mode: input mode in form of PTRACE_MODE_* 396 * 397 * Returns a converted MAY_* mode usable by smack rules 398 */ 399 static inline unsigned int smk_ptrace_mode(unsigned int mode) 400 { 401 if (mode & PTRACE_MODE_ATTACH) 402 return MAY_READWRITE; 403 if (mode & PTRACE_MODE_READ) 404 return MAY_READ; 405 406 return 0; 407 } 408 409 /** 410 * smk_ptrace_rule_check - helper for ptrace access 411 * @tracer: tracer process 412 * @tracee_known: label entry of the process that's about to be traced 413 * @mode: ptrace attachment mode (PTRACE_MODE_*) 414 * @func: name of the function that called us, used for audit 415 * 416 * Returns 0 on access granted, -error on error 417 */ 418 static int smk_ptrace_rule_check(struct task_struct *tracer, 419 struct smack_known *tracee_known, 420 unsigned int mode, const char *func) 421 { 422 int rc; 423 struct smk_audit_info ad, *saip = NULL; 424 struct task_smack *tsp; 425 struct smack_known *tracer_known; 426 const struct cred *tracercred; 427 428 if ((mode & PTRACE_MODE_NOAUDIT) == 0) { 429 smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK); 430 smk_ad_setfield_u_tsk(&ad, tracer); 431 saip = &ad; 432 } 433 434 rcu_read_lock(); 435 tracercred = __task_cred(tracer); 436 tsp = smack_cred(tracercred); 437 tracer_known = smk_of_task(tsp); 438 439 if ((mode & PTRACE_MODE_ATTACH) && 440 (smack_ptrace_rule == SMACK_PTRACE_EXACT || 441 smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) { 442 if (tracer_known->smk_known == tracee_known->smk_known) 443 rc = 0; 444 else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN) 445 rc = -EACCES; 446 else if (smack_privileged_cred(CAP_SYS_PTRACE, tracercred)) 447 rc = 0; 448 else 449 rc = -EACCES; 450 451 if (saip) 452 smack_log(tracer_known->smk_known, 453 tracee_known->smk_known, 454 0, rc, saip); 455 456 rcu_read_unlock(); 457 return rc; 458 } 459 460 /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */ 461 rc = smk_tskacc(tsp, tracee_known, smk_ptrace_mode(mode), saip); 462 463 rcu_read_unlock(); 464 return rc; 465 } 466 467 /* 468 * LSM hooks. 469 * We he, that is fun! 470 */ 471 472 /** 473 * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH 474 * @ctp: child task pointer 475 * @mode: ptrace attachment mode (PTRACE_MODE_*) 476 * 477 * Returns 0 if access is OK, an error code otherwise 478 * 479 * Do the capability checks. 480 */ 481 static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) 482 { 483 struct smack_known *skp; 484 485 skp = smk_of_task_struct_obj(ctp); 486 487 return smk_ptrace_rule_check(current, skp, mode, __func__); 488 } 489 490 /** 491 * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME 492 * @ptp: parent task pointer 493 * 494 * Returns 0 if access is OK, an error code otherwise 495 * 496 * Do the capability checks, and require PTRACE_MODE_ATTACH. 497 */ 498 static int smack_ptrace_traceme(struct task_struct *ptp) 499 { 500 struct smack_known *skp; 501 502 skp = smk_of_task(smack_cred(current_cred())); 503 504 return smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__); 505 } 506 507 /** 508 * smack_syslog - Smack approval on syslog 509 * @typefrom_file: unused 510 * 511 * Returns 0 on success, error code otherwise. 512 */ 513 static int smack_syslog(int typefrom_file) 514 { 515 int rc = 0; 516 struct smack_known *skp = smk_of_current(); 517 518 if (smack_privileged(CAP_MAC_OVERRIDE)) 519 return 0; 520 521 if (smack_syslog_label != NULL && smack_syslog_label != skp) 522 rc = -EACCES; 523 524 return rc; 525 } 526 527 /* 528 * Superblock Hooks. 529 */ 530 531 /** 532 * smack_sb_alloc_security - allocate a superblock blob 533 * @sb: the superblock getting the blob 534 * 535 * Returns 0 on success or -ENOMEM on error. 536 */ 537 static int smack_sb_alloc_security(struct super_block *sb) 538 { 539 struct superblock_smack *sbsp = smack_superblock(sb); 540 541 sbsp->smk_root = &smack_known_floor; 542 sbsp->smk_default = &smack_known_floor; 543 sbsp->smk_floor = &smack_known_floor; 544 sbsp->smk_hat = &smack_known_hat; 545 /* 546 * SMK_SB_INITIALIZED will be zero from kzalloc. 547 */ 548 549 return 0; 550 } 551 552 struct smack_mnt_opts { 553 const char *fsdefault, *fsfloor, *fshat, *fsroot, *fstransmute; 554 }; 555 556 static void smack_free_mnt_opts(void *mnt_opts) 557 { 558 struct smack_mnt_opts *opts = mnt_opts; 559 kfree(opts->fsdefault); 560 kfree(opts->fsfloor); 561 kfree(opts->fshat); 562 kfree(opts->fsroot); 563 kfree(opts->fstransmute); 564 kfree(opts); 565 } 566 567 static int smack_add_opt(int token, const char *s, void **mnt_opts) 568 { 569 struct smack_mnt_opts *opts = *mnt_opts; 570 571 if (!opts) { 572 opts = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL); 573 if (!opts) 574 return -ENOMEM; 575 *mnt_opts = opts; 576 } 577 if (!s) 578 return -ENOMEM; 579 580 switch (token) { 581 case Opt_fsdefault: 582 if (opts->fsdefault) 583 goto out_opt_err; 584 opts->fsdefault = s; 585 break; 586 case Opt_fsfloor: 587 if (opts->fsfloor) 588 goto out_opt_err; 589 opts->fsfloor = s; 590 break; 591 case Opt_fshat: 592 if (opts->fshat) 593 goto out_opt_err; 594 opts->fshat = s; 595 break; 596 case Opt_fsroot: 597 if (opts->fsroot) 598 goto out_opt_err; 599 opts->fsroot = s; 600 break; 601 case Opt_fstransmute: 602 if (opts->fstransmute) 603 goto out_opt_err; 604 opts->fstransmute = s; 605 break; 606 } 607 return 0; 608 609 out_opt_err: 610 pr_warn("Smack: duplicate mount options\n"); 611 return -EINVAL; 612 } 613 614 /** 615 * smack_fs_context_dup - Duplicate the security data on fs_context duplication 616 * @fc: The new filesystem context. 617 * @src_fc: The source filesystem context being duplicated. 618 * 619 * Returns 0 on success or -ENOMEM on error. 620 */ 621 static int smack_fs_context_dup(struct fs_context *fc, 622 struct fs_context *src_fc) 623 { 624 struct smack_mnt_opts *dst, *src = src_fc->security; 625 626 if (!src) 627 return 0; 628 629 fc->security = kzalloc(sizeof(struct smack_mnt_opts), GFP_KERNEL); 630 if (!fc->security) 631 return -ENOMEM; 632 dst = fc->security; 633 634 if (src->fsdefault) { 635 dst->fsdefault = kstrdup(src->fsdefault, GFP_KERNEL); 636 if (!dst->fsdefault) 637 return -ENOMEM; 638 } 639 if (src->fsfloor) { 640 dst->fsfloor = kstrdup(src->fsfloor, GFP_KERNEL); 641 if (!dst->fsfloor) 642 return -ENOMEM; 643 } 644 if (src->fshat) { 645 dst->fshat = kstrdup(src->fshat, GFP_KERNEL); 646 if (!dst->fshat) 647 return -ENOMEM; 648 } 649 if (src->fsroot) { 650 dst->fsroot = kstrdup(src->fsroot, GFP_KERNEL); 651 if (!dst->fsroot) 652 return -ENOMEM; 653 } 654 if (src->fstransmute) { 655 dst->fstransmute = kstrdup(src->fstransmute, GFP_KERNEL); 656 if (!dst->fstransmute) 657 return -ENOMEM; 658 } 659 return 0; 660 } 661 662 static const struct fs_parameter_spec smack_fs_parameters[] = { 663 fsparam_string("smackfsdef", Opt_fsdefault), 664 fsparam_string("smackfsdefault", Opt_fsdefault), 665 fsparam_string("smackfsfloor", Opt_fsfloor), 666 fsparam_string("smackfshat", Opt_fshat), 667 fsparam_string("smackfsroot", Opt_fsroot), 668 fsparam_string("smackfstransmute", Opt_fstransmute), 669 {} 670 }; 671 672 /** 673 * smack_fs_context_parse_param - Parse a single mount parameter 674 * @fc: The new filesystem context being constructed. 675 * @param: The parameter. 676 * 677 * Returns 0 on success, -ENOPARAM to pass the parameter on or anything else on 678 * error. 679 */ 680 static int smack_fs_context_parse_param(struct fs_context *fc, 681 struct fs_parameter *param) 682 { 683 struct fs_parse_result result; 684 int opt, rc; 685 686 opt = fs_parse(fc, smack_fs_parameters, param, &result); 687 if (opt < 0) 688 return opt; 689 690 rc = smack_add_opt(opt, param->string, &fc->security); 691 if (!rc) 692 param->string = NULL; 693 return rc; 694 } 695 696 static int smack_sb_eat_lsm_opts(char *options, void **mnt_opts) 697 { 698 char *from = options, *to = options; 699 bool first = true; 700 701 while (1) { 702 char *next = strchr(from, ','); 703 int token, len, rc; 704 char *arg = NULL; 705 706 if (next) 707 len = next - from; 708 else 709 len = strlen(from); 710 711 token = match_opt_prefix(from, len, &arg); 712 if (token != Opt_error) { 713 arg = kmemdup_nul(arg, from + len - arg, GFP_KERNEL); 714 rc = smack_add_opt(token, arg, mnt_opts); 715 if (unlikely(rc)) { 716 kfree(arg); 717 if (*mnt_opts) 718 smack_free_mnt_opts(*mnt_opts); 719 *mnt_opts = NULL; 720 return rc; 721 } 722 } else { 723 if (!first) { // copy with preceding comma 724 from--; 725 len++; 726 } 727 if (to != from) 728 memmove(to, from, len); 729 to += len; 730 first = false; 731 } 732 if (!from[len]) 733 break; 734 from += len + 1; 735 } 736 *to = '\0'; 737 return 0; 738 } 739 740 /** 741 * smack_set_mnt_opts - set Smack specific mount options 742 * @sb: the file system superblock 743 * @mnt_opts: Smack mount options 744 * @kern_flags: mount option from kernel space or user space 745 * @set_kern_flags: where to store converted mount opts 746 * 747 * Returns 0 on success, an error code on failure 748 * 749 * Allow filesystems with binary mount data to explicitly set Smack mount 750 * labels. 751 */ 752 static int smack_set_mnt_opts(struct super_block *sb, 753 void *mnt_opts, 754 unsigned long kern_flags, 755 unsigned long *set_kern_flags) 756 { 757 struct dentry *root = sb->s_root; 758 struct inode *inode = d_backing_inode(root); 759 struct superblock_smack *sp = smack_superblock(sb); 760 struct inode_smack *isp; 761 struct smack_known *skp; 762 struct smack_mnt_opts *opts = mnt_opts; 763 bool transmute = false; 764 765 if (sp->smk_flags & SMK_SB_INITIALIZED) 766 return 0; 767 768 if (!smack_privileged(CAP_MAC_ADMIN)) { 769 /* 770 * Unprivileged mounts don't get to specify Smack values. 771 */ 772 if (opts) 773 return -EPERM; 774 /* 775 * Unprivileged mounts get root and default from the caller. 776 */ 777 skp = smk_of_current(); 778 sp->smk_root = skp; 779 sp->smk_default = skp; 780 /* 781 * For a handful of fs types with no user-controlled 782 * backing store it's okay to trust security labels 783 * in the filesystem. The rest are untrusted. 784 */ 785 if (sb->s_user_ns != &init_user_ns && 786 sb->s_magic != SYSFS_MAGIC && sb->s_magic != TMPFS_MAGIC && 787 sb->s_magic != RAMFS_MAGIC) { 788 transmute = true; 789 sp->smk_flags |= SMK_SB_UNTRUSTED; 790 } 791 } 792 793 sp->smk_flags |= SMK_SB_INITIALIZED; 794 795 if (opts) { 796 if (opts->fsdefault) { 797 skp = smk_import_entry(opts->fsdefault, 0); 798 if (IS_ERR(skp)) 799 return PTR_ERR(skp); 800 sp->smk_default = skp; 801 } 802 if (opts->fsfloor) { 803 skp = smk_import_entry(opts->fsfloor, 0); 804 if (IS_ERR(skp)) 805 return PTR_ERR(skp); 806 sp->smk_floor = skp; 807 } 808 if (opts->fshat) { 809 skp = smk_import_entry(opts->fshat, 0); 810 if (IS_ERR(skp)) 811 return PTR_ERR(skp); 812 sp->smk_hat = skp; 813 } 814 if (opts->fsroot) { 815 skp = smk_import_entry(opts->fsroot, 0); 816 if (IS_ERR(skp)) 817 return PTR_ERR(skp); 818 sp->smk_root = skp; 819 } 820 if (opts->fstransmute) { 821 skp = smk_import_entry(opts->fstransmute, 0); 822 if (IS_ERR(skp)) 823 return PTR_ERR(skp); 824 sp->smk_root = skp; 825 transmute = true; 826 } 827 } 828 829 /* 830 * Initialize the root inode. 831 */ 832 init_inode_smack(inode, sp->smk_root); 833 834 if (transmute) { 835 isp = smack_inode(inode); 836 isp->smk_flags |= SMK_INODE_TRANSMUTE; 837 } 838 839 return 0; 840 } 841 842 /** 843 * smack_sb_statfs - Smack check on statfs 844 * @dentry: identifies the file system in question 845 * 846 * Returns 0 if current can read the floor of the filesystem, 847 * and error code otherwise 848 */ 849 static int smack_sb_statfs(struct dentry *dentry) 850 { 851 struct superblock_smack *sbp = smack_superblock(dentry->d_sb); 852 int rc; 853 struct smk_audit_info ad; 854 855 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 856 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 857 858 rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); 859 rc = smk_bu_current("statfs", sbp->smk_floor, MAY_READ, rc); 860 return rc; 861 } 862 863 /* 864 * BPRM hooks 865 */ 866 867 /** 868 * smack_bprm_creds_for_exec - Update bprm->cred if needed for exec 869 * @bprm: the exec information 870 * 871 * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise 872 */ 873 static int smack_bprm_creds_for_exec(struct linux_binprm *bprm) 874 { 875 struct inode *inode = file_inode(bprm->file); 876 struct task_smack *bsp = smack_cred(bprm->cred); 877 struct inode_smack *isp; 878 struct superblock_smack *sbsp; 879 int rc; 880 881 isp = smack_inode(inode); 882 if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task) 883 return 0; 884 885 sbsp = smack_superblock(inode->i_sb); 886 if ((sbsp->smk_flags & SMK_SB_UNTRUSTED) && 887 isp->smk_task != sbsp->smk_root) 888 return 0; 889 890 if (bprm->unsafe & LSM_UNSAFE_PTRACE) { 891 struct task_struct *tracer; 892 rc = 0; 893 894 rcu_read_lock(); 895 tracer = ptrace_parent(current); 896 if (likely(tracer != NULL)) 897 rc = smk_ptrace_rule_check(tracer, 898 isp->smk_task, 899 PTRACE_MODE_ATTACH, 900 __func__); 901 rcu_read_unlock(); 902 903 if (rc != 0) 904 return rc; 905 } 906 if (bprm->unsafe & ~LSM_UNSAFE_PTRACE) 907 return -EPERM; 908 909 bsp->smk_task = isp->smk_task; 910 bprm->per_clear |= PER_CLEAR_ON_SETID; 911 912 /* Decide if this is a secure exec. */ 913 if (bsp->smk_task != bsp->smk_forked) 914 bprm->secureexec = 1; 915 916 return 0; 917 } 918 919 /* 920 * Inode hooks 921 */ 922 923 /** 924 * smack_inode_alloc_security - allocate an inode blob 925 * @inode: the inode in need of a blob 926 * 927 * Returns 0 928 */ 929 static int smack_inode_alloc_security(struct inode *inode) 930 { 931 struct smack_known *skp = smk_of_current(); 932 933 init_inode_smack(inode, skp); 934 return 0; 935 } 936 937 /** 938 * smack_inode_init_security - copy out the smack from an inode 939 * @inode: the newly created inode 940 * @dir: containing directory object 941 * @qstr: unused 942 * @name: where to put the attribute name 943 * @value: where to put the attribute value 944 * @len: where to put the length of the attribute 945 * 946 * Returns 0 if it all works out, -ENOMEM if there's no memory 947 */ 948 static int smack_inode_init_security(struct inode *inode, struct inode *dir, 949 const struct qstr *qstr, const char **name, 950 void **value, size_t *len) 951 { 952 struct inode_smack *issp = smack_inode(inode); 953 struct smack_known *skp = smk_of_current(); 954 struct smack_known *isp = smk_of_inode(inode); 955 struct smack_known *dsp = smk_of_inode(dir); 956 int may; 957 958 if (name) 959 *name = XATTR_SMACK_SUFFIX; 960 961 if (value && len) { 962 rcu_read_lock(); 963 may = smk_access_entry(skp->smk_known, dsp->smk_known, 964 &skp->smk_rules); 965 rcu_read_unlock(); 966 967 /* 968 * If the access rule allows transmutation and 969 * the directory requests transmutation then 970 * by all means transmute. 971 * Mark the inode as changed. 972 */ 973 if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && 974 smk_inode_transmutable(dir)) { 975 isp = dsp; 976 issp->smk_flags |= SMK_INODE_CHANGED; 977 } 978 979 *value = kstrdup(isp->smk_known, GFP_NOFS); 980 if (*value == NULL) 981 return -ENOMEM; 982 983 *len = strlen(isp->smk_known); 984 } 985 986 return 0; 987 } 988 989 /** 990 * smack_inode_link - Smack check on link 991 * @old_dentry: the existing object 992 * @dir: unused 993 * @new_dentry: the new object 994 * 995 * Returns 0 if access is permitted, an error code otherwise 996 */ 997 static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, 998 struct dentry *new_dentry) 999 { 1000 struct smack_known *isp; 1001 struct smk_audit_info ad; 1002 int rc; 1003 1004 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1005 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); 1006 1007 isp = smk_of_inode(d_backing_inode(old_dentry)); 1008 rc = smk_curacc(isp, MAY_WRITE, &ad); 1009 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_WRITE, rc); 1010 1011 if (rc == 0 && d_is_positive(new_dentry)) { 1012 isp = smk_of_inode(d_backing_inode(new_dentry)); 1013 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); 1014 rc = smk_curacc(isp, MAY_WRITE, &ad); 1015 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_WRITE, rc); 1016 } 1017 1018 return rc; 1019 } 1020 1021 /** 1022 * smack_inode_unlink - Smack check on inode deletion 1023 * @dir: containing directory object 1024 * @dentry: file to unlink 1025 * 1026 * Returns 0 if current can write the containing directory 1027 * and the object, error code otherwise 1028 */ 1029 static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) 1030 { 1031 struct inode *ip = d_backing_inode(dentry); 1032 struct smk_audit_info ad; 1033 int rc; 1034 1035 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1036 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1037 1038 /* 1039 * You need write access to the thing you're unlinking 1040 */ 1041 rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); 1042 rc = smk_bu_inode(ip, MAY_WRITE, rc); 1043 if (rc == 0) { 1044 /* 1045 * You also need write access to the containing directory 1046 */ 1047 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); 1048 smk_ad_setfield_u_fs_inode(&ad, dir); 1049 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); 1050 rc = smk_bu_inode(dir, MAY_WRITE, rc); 1051 } 1052 return rc; 1053 } 1054 1055 /** 1056 * smack_inode_rmdir - Smack check on directory deletion 1057 * @dir: containing directory object 1058 * @dentry: directory to unlink 1059 * 1060 * Returns 0 if current can write the containing directory 1061 * and the directory, error code otherwise 1062 */ 1063 static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) 1064 { 1065 struct smk_audit_info ad; 1066 int rc; 1067 1068 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1069 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1070 1071 /* 1072 * You need write access to the thing you're removing 1073 */ 1074 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad); 1075 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); 1076 if (rc == 0) { 1077 /* 1078 * You also need write access to the containing directory 1079 */ 1080 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); 1081 smk_ad_setfield_u_fs_inode(&ad, dir); 1082 rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); 1083 rc = smk_bu_inode(dir, MAY_WRITE, rc); 1084 } 1085 1086 return rc; 1087 } 1088 1089 /** 1090 * smack_inode_rename - Smack check on rename 1091 * @old_inode: unused 1092 * @old_dentry: the old object 1093 * @new_inode: unused 1094 * @new_dentry: the new object 1095 * 1096 * Read and write access is required on both the old and 1097 * new directories. 1098 * 1099 * Returns 0 if access is permitted, an error code otherwise 1100 */ 1101 static int smack_inode_rename(struct inode *old_inode, 1102 struct dentry *old_dentry, 1103 struct inode *new_inode, 1104 struct dentry *new_dentry) 1105 { 1106 int rc; 1107 struct smack_known *isp; 1108 struct smk_audit_info ad; 1109 1110 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1111 smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); 1112 1113 isp = smk_of_inode(d_backing_inode(old_dentry)); 1114 rc = smk_curacc(isp, MAY_READWRITE, &ad); 1115 rc = smk_bu_inode(d_backing_inode(old_dentry), MAY_READWRITE, rc); 1116 1117 if (rc == 0 && d_is_positive(new_dentry)) { 1118 isp = smk_of_inode(d_backing_inode(new_dentry)); 1119 smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); 1120 rc = smk_curacc(isp, MAY_READWRITE, &ad); 1121 rc = smk_bu_inode(d_backing_inode(new_dentry), MAY_READWRITE, rc); 1122 } 1123 return rc; 1124 } 1125 1126 /** 1127 * smack_inode_permission - Smack version of permission() 1128 * @inode: the inode in question 1129 * @mask: the access requested 1130 * 1131 * This is the important Smack hook. 1132 * 1133 * Returns 0 if access is permitted, an error code otherwise 1134 */ 1135 static int smack_inode_permission(struct inode *inode, int mask) 1136 { 1137 struct superblock_smack *sbsp = smack_superblock(inode->i_sb); 1138 struct smk_audit_info ad; 1139 int no_block = mask & MAY_NOT_BLOCK; 1140 int rc; 1141 1142 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); 1143 /* 1144 * No permission to check. Existence test. Yup, it's there. 1145 */ 1146 if (mask == 0) 1147 return 0; 1148 1149 if (sbsp->smk_flags & SMK_SB_UNTRUSTED) { 1150 if (smk_of_inode(inode) != sbsp->smk_root) 1151 return -EACCES; 1152 } 1153 1154 /* May be droppable after audit */ 1155 if (no_block) 1156 return -ECHILD; 1157 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); 1158 smk_ad_setfield_u_fs_inode(&ad, inode); 1159 rc = smk_curacc(smk_of_inode(inode), mask, &ad); 1160 rc = smk_bu_inode(inode, mask, rc); 1161 return rc; 1162 } 1163 1164 /** 1165 * smack_inode_setattr - Smack check for setting attributes 1166 * @dentry: the object 1167 * @iattr: for the force flag 1168 * 1169 * Returns 0 if access is permitted, an error code otherwise 1170 */ 1171 static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) 1172 { 1173 struct smk_audit_info ad; 1174 int rc; 1175 1176 /* 1177 * Need to allow for clearing the setuid bit. 1178 */ 1179 if (iattr->ia_valid & ATTR_FORCE) 1180 return 0; 1181 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1182 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1183 1184 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad); 1185 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); 1186 return rc; 1187 } 1188 1189 /** 1190 * smack_inode_getattr - Smack check for getting attributes 1191 * @path: path to extract the info from 1192 * 1193 * Returns 0 if access is permitted, an error code otherwise 1194 */ 1195 static int smack_inode_getattr(const struct path *path) 1196 { 1197 struct smk_audit_info ad; 1198 struct inode *inode = d_backing_inode(path->dentry); 1199 int rc; 1200 1201 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1202 smk_ad_setfield_u_fs_path(&ad, *path); 1203 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad); 1204 rc = smk_bu_inode(inode, MAY_READ, rc); 1205 return rc; 1206 } 1207 1208 /** 1209 * smack_inode_setxattr - Smack check for setting xattrs 1210 * @mnt_userns: active user namespace 1211 * @dentry: the object 1212 * @name: name of the attribute 1213 * @value: value of the attribute 1214 * @size: size of the value 1215 * @flags: unused 1216 * 1217 * This protects the Smack attribute explicitly. 1218 * 1219 * Returns 0 if access is permitted, an error code otherwise 1220 */ 1221 static int smack_inode_setxattr(struct user_namespace *mnt_userns, 1222 struct dentry *dentry, const char *name, 1223 const void *value, size_t size, int flags) 1224 { 1225 struct smk_audit_info ad; 1226 struct smack_known *skp; 1227 int check_priv = 0; 1228 int check_import = 0; 1229 int check_star = 0; 1230 int rc = 0; 1231 1232 /* 1233 * Check label validity here so import won't fail in post_setxattr 1234 */ 1235 if (strcmp(name, XATTR_NAME_SMACK) == 0 || 1236 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || 1237 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { 1238 check_priv = 1; 1239 check_import = 1; 1240 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || 1241 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { 1242 check_priv = 1; 1243 check_import = 1; 1244 check_star = 1; 1245 } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { 1246 check_priv = 1; 1247 if (size != TRANS_TRUE_SIZE || 1248 strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0) 1249 rc = -EINVAL; 1250 } else 1251 rc = cap_inode_setxattr(dentry, name, value, size, flags); 1252 1253 if (check_priv && !smack_privileged(CAP_MAC_ADMIN)) 1254 rc = -EPERM; 1255 1256 if (rc == 0 && check_import) { 1257 skp = size ? smk_import_entry(value, size) : NULL; 1258 if (IS_ERR(skp)) 1259 rc = PTR_ERR(skp); 1260 else if (skp == NULL || (check_star && 1261 (skp == &smack_known_star || skp == &smack_known_web))) 1262 rc = -EINVAL; 1263 } 1264 1265 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1266 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1267 1268 if (rc == 0) { 1269 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad); 1270 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); 1271 } 1272 1273 return rc; 1274 } 1275 1276 /** 1277 * smack_inode_post_setxattr - Apply the Smack update approved above 1278 * @dentry: object 1279 * @name: attribute name 1280 * @value: attribute value 1281 * @size: attribute size 1282 * @flags: unused 1283 * 1284 * Set the pointer in the inode blob to the entry found 1285 * in the master label list. 1286 */ 1287 static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, 1288 const void *value, size_t size, int flags) 1289 { 1290 struct smack_known *skp; 1291 struct inode_smack *isp = smack_inode(d_backing_inode(dentry)); 1292 1293 if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { 1294 isp->smk_flags |= SMK_INODE_TRANSMUTE; 1295 return; 1296 } 1297 1298 if (strcmp(name, XATTR_NAME_SMACK) == 0) { 1299 skp = smk_import_entry(value, size); 1300 if (!IS_ERR(skp)) 1301 isp->smk_inode = skp; 1302 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) { 1303 skp = smk_import_entry(value, size); 1304 if (!IS_ERR(skp)) 1305 isp->smk_task = skp; 1306 } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { 1307 skp = smk_import_entry(value, size); 1308 if (!IS_ERR(skp)) 1309 isp->smk_mmap = skp; 1310 } 1311 1312 return; 1313 } 1314 1315 /** 1316 * smack_inode_getxattr - Smack check on getxattr 1317 * @dentry: the object 1318 * @name: unused 1319 * 1320 * Returns 0 if access is permitted, an error code otherwise 1321 */ 1322 static int smack_inode_getxattr(struct dentry *dentry, const char *name) 1323 { 1324 struct smk_audit_info ad; 1325 int rc; 1326 1327 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1328 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1329 1330 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_READ, &ad); 1331 rc = smk_bu_inode(d_backing_inode(dentry), MAY_READ, rc); 1332 return rc; 1333 } 1334 1335 /** 1336 * smack_inode_removexattr - Smack check on removexattr 1337 * @mnt_userns: active user namespace 1338 * @dentry: the object 1339 * @name: name of the attribute 1340 * 1341 * Removing the Smack attribute requires CAP_MAC_ADMIN 1342 * 1343 * Returns 0 if access is permitted, an error code otherwise 1344 */ 1345 static int smack_inode_removexattr(struct user_namespace *mnt_userns, 1346 struct dentry *dentry, const char *name) 1347 { 1348 struct inode_smack *isp; 1349 struct smk_audit_info ad; 1350 int rc = 0; 1351 1352 if (strcmp(name, XATTR_NAME_SMACK) == 0 || 1353 strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || 1354 strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || 1355 strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || 1356 strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 || 1357 strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { 1358 if (!smack_privileged(CAP_MAC_ADMIN)) 1359 rc = -EPERM; 1360 } else 1361 rc = cap_inode_removexattr(mnt_userns, dentry, name); 1362 1363 if (rc != 0) 1364 return rc; 1365 1366 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); 1367 smk_ad_setfield_u_fs_path_dentry(&ad, dentry); 1368 1369 rc = smk_curacc(smk_of_inode(d_backing_inode(dentry)), MAY_WRITE, &ad); 1370 rc = smk_bu_inode(d_backing_inode(dentry), MAY_WRITE, rc); 1371 if (rc != 0) 1372 return rc; 1373 1374 isp = smack_inode(d_backing_inode(dentry)); 1375 /* 1376 * Don't do anything special for these. 1377 * XATTR_NAME_SMACKIPIN 1378 * XATTR_NAME_SMACKIPOUT 1379 */ 1380 if (strcmp(name, XATTR_NAME_SMACK) == 0) { 1381 struct super_block *sbp = dentry->d_sb; 1382 struct superblock_smack *sbsp = smack_superblock(sbp); 1383 1384 isp->smk_inode = sbsp->smk_default; 1385 } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) 1386 isp->smk_task = NULL; 1387 else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) 1388 isp->smk_mmap = NULL; 1389 else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) 1390 isp->smk_flags &= ~SMK_INODE_TRANSMUTE; 1391 1392 return 0; 1393 } 1394 1395 /** 1396 * smack_inode_getsecurity - get smack xattrs 1397 * @mnt_userns: active user namespace 1398 * @inode: the object 1399 * @name: attribute name 1400 * @buffer: where to put the result 1401 * @alloc: duplicate memory 1402 * 1403 * Returns the size of the attribute or an error code 1404 */ 1405 static int smack_inode_getsecurity(struct user_namespace *mnt_userns, 1406 struct inode *inode, const char *name, 1407 void **buffer, bool alloc) 1408 { 1409 struct socket_smack *ssp; 1410 struct socket *sock; 1411 struct super_block *sbp; 1412 struct inode *ip = (struct inode *)inode; 1413 struct smack_known *isp; 1414 1415 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) 1416 isp = smk_of_inode(inode); 1417 else { 1418 /* 1419 * The rest of the Smack xattrs are only on sockets. 1420 */ 1421 sbp = ip->i_sb; 1422 if (sbp->s_magic != SOCKFS_MAGIC) 1423 return -EOPNOTSUPP; 1424 1425 sock = SOCKET_I(ip); 1426 if (sock == NULL || sock->sk == NULL) 1427 return -EOPNOTSUPP; 1428 1429 ssp = sock->sk->sk_security; 1430 1431 if (strcmp(name, XATTR_SMACK_IPIN) == 0) 1432 isp = ssp->smk_in; 1433 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) 1434 isp = ssp->smk_out; 1435 else 1436 return -EOPNOTSUPP; 1437 } 1438 1439 if (alloc) { 1440 *buffer = kstrdup(isp->smk_known, GFP_KERNEL); 1441 if (*buffer == NULL) 1442 return -ENOMEM; 1443 } 1444 1445 return strlen(isp->smk_known); 1446 } 1447 1448 1449 /** 1450 * smack_inode_listsecurity - list the Smack attributes 1451 * @inode: the object 1452 * @buffer: where they go 1453 * @buffer_size: size of buffer 1454 */ 1455 static int smack_inode_listsecurity(struct inode *inode, char *buffer, 1456 size_t buffer_size) 1457 { 1458 int len = sizeof(XATTR_NAME_SMACK); 1459 1460 if (buffer != NULL && len <= buffer_size) 1461 memcpy(buffer, XATTR_NAME_SMACK, len); 1462 1463 return len; 1464 } 1465 1466 /** 1467 * smack_inode_getsecid - Extract inode's security id 1468 * @inode: inode to extract the info from 1469 * @secid: where result will be saved 1470 */ 1471 static void smack_inode_getsecid(struct inode *inode, u32 *secid) 1472 { 1473 struct smack_known *skp = smk_of_inode(inode); 1474 1475 *secid = skp->smk_secid; 1476 } 1477 1478 /* 1479 * File Hooks 1480 */ 1481 1482 /* 1483 * There is no smack_file_permission hook 1484 * 1485 * Should access checks be done on each read or write? 1486 * UNICOS and SELinux say yes. 1487 * Trusted Solaris, Trusted Irix, and just about everyone else says no. 1488 * 1489 * I'll say no for now. Smack does not do the frequent 1490 * label changing that SELinux does. 1491 */ 1492 1493 /** 1494 * smack_file_alloc_security - assign a file security blob 1495 * @file: the object 1496 * 1497 * The security blob for a file is a pointer to the master 1498 * label list, so no allocation is done. 1499 * 1500 * f_security is the owner security information. It 1501 * isn't used on file access checks, it's for send_sigio. 1502 * 1503 * Returns 0 1504 */ 1505 static int smack_file_alloc_security(struct file *file) 1506 { 1507 struct smack_known **blob = smack_file(file); 1508 1509 *blob = smk_of_current(); 1510 return 0; 1511 } 1512 1513 /** 1514 * smack_file_ioctl - Smack check on ioctls 1515 * @file: the object 1516 * @cmd: what to do 1517 * @arg: unused 1518 * 1519 * Relies heavily on the correct use of the ioctl command conventions. 1520 * 1521 * Returns 0 if allowed, error code otherwise 1522 */ 1523 static int smack_file_ioctl(struct file *file, unsigned int cmd, 1524 unsigned long arg) 1525 { 1526 int rc = 0; 1527 struct smk_audit_info ad; 1528 struct inode *inode = file_inode(file); 1529 1530 if (unlikely(IS_PRIVATE(inode))) 1531 return 0; 1532 1533 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1534 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1535 1536 if (_IOC_DIR(cmd) & _IOC_WRITE) { 1537 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad); 1538 rc = smk_bu_file(file, MAY_WRITE, rc); 1539 } 1540 1541 if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) { 1542 rc = smk_curacc(smk_of_inode(inode), MAY_READ, &ad); 1543 rc = smk_bu_file(file, MAY_READ, rc); 1544 } 1545 1546 return rc; 1547 } 1548 1549 /** 1550 * smack_file_lock - Smack check on file locking 1551 * @file: the object 1552 * @cmd: unused 1553 * 1554 * Returns 0 if current has lock access, error code otherwise 1555 */ 1556 static int smack_file_lock(struct file *file, unsigned int cmd) 1557 { 1558 struct smk_audit_info ad; 1559 int rc; 1560 struct inode *inode = file_inode(file); 1561 1562 if (unlikely(IS_PRIVATE(inode))) 1563 return 0; 1564 1565 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1566 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1567 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad); 1568 rc = smk_bu_file(file, MAY_LOCK, rc); 1569 return rc; 1570 } 1571 1572 /** 1573 * smack_file_fcntl - Smack check on fcntl 1574 * @file: the object 1575 * @cmd: what action to check 1576 * @arg: unused 1577 * 1578 * Generally these operations are harmless. 1579 * File locking operations present an obvious mechanism 1580 * for passing information, so they require write access. 1581 * 1582 * Returns 0 if current has access, error code otherwise 1583 */ 1584 static int smack_file_fcntl(struct file *file, unsigned int cmd, 1585 unsigned long arg) 1586 { 1587 struct smk_audit_info ad; 1588 int rc = 0; 1589 struct inode *inode = file_inode(file); 1590 1591 if (unlikely(IS_PRIVATE(inode))) 1592 return 0; 1593 1594 switch (cmd) { 1595 case F_GETLK: 1596 break; 1597 case F_SETLK: 1598 case F_SETLKW: 1599 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1600 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1601 rc = smk_curacc(smk_of_inode(inode), MAY_LOCK, &ad); 1602 rc = smk_bu_file(file, MAY_LOCK, rc); 1603 break; 1604 case F_SETOWN: 1605 case F_SETSIG: 1606 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1607 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1608 rc = smk_curacc(smk_of_inode(inode), MAY_WRITE, &ad); 1609 rc = smk_bu_file(file, MAY_WRITE, rc); 1610 break; 1611 default: 1612 break; 1613 } 1614 1615 return rc; 1616 } 1617 1618 /** 1619 * smack_mmap_file - Check permissions for a mmap operation. 1620 * @file: contains the file structure for file to map (may be NULL). 1621 * @reqprot: contains the protection requested by the application. 1622 * @prot: contains the protection that will be applied by the kernel. 1623 * @flags: contains the operational flags. 1624 * 1625 * The @file may be NULL, e.g. if mapping anonymous memory. 1626 * 1627 * Return 0 if permission is granted. 1628 */ 1629 static int smack_mmap_file(struct file *file, 1630 unsigned long reqprot, unsigned long prot, 1631 unsigned long flags) 1632 { 1633 struct smack_known *skp; 1634 struct smack_known *mkp; 1635 struct smack_rule *srp; 1636 struct task_smack *tsp; 1637 struct smack_known *okp; 1638 struct inode_smack *isp; 1639 struct superblock_smack *sbsp; 1640 int may; 1641 int mmay; 1642 int tmay; 1643 int rc; 1644 1645 if (file == NULL) 1646 return 0; 1647 1648 if (unlikely(IS_PRIVATE(file_inode(file)))) 1649 return 0; 1650 1651 isp = smack_inode(file_inode(file)); 1652 if (isp->smk_mmap == NULL) 1653 return 0; 1654 sbsp = smack_superblock(file_inode(file)->i_sb); 1655 if (sbsp->smk_flags & SMK_SB_UNTRUSTED && 1656 isp->smk_mmap != sbsp->smk_root) 1657 return -EACCES; 1658 mkp = isp->smk_mmap; 1659 1660 tsp = smack_cred(current_cred()); 1661 skp = smk_of_current(); 1662 rc = 0; 1663 1664 rcu_read_lock(); 1665 /* 1666 * For each Smack rule associated with the subject 1667 * label verify that the SMACK64MMAP also has access 1668 * to that rule's object label. 1669 */ 1670 list_for_each_entry_rcu(srp, &skp->smk_rules, list) { 1671 okp = srp->smk_object; 1672 /* 1673 * Matching labels always allows access. 1674 */ 1675 if (mkp->smk_known == okp->smk_known) 1676 continue; 1677 /* 1678 * If there is a matching local rule take 1679 * that into account as well. 1680 */ 1681 may = smk_access_entry(srp->smk_subject->smk_known, 1682 okp->smk_known, 1683 &tsp->smk_rules); 1684 if (may == -ENOENT) 1685 may = srp->smk_access; 1686 else 1687 may &= srp->smk_access; 1688 /* 1689 * If may is zero the SMACK64MMAP subject can't 1690 * possibly have less access. 1691 */ 1692 if (may == 0) 1693 continue; 1694 1695 /* 1696 * Fetch the global list entry. 1697 * If there isn't one a SMACK64MMAP subject 1698 * can't have as much access as current. 1699 */ 1700 mmay = smk_access_entry(mkp->smk_known, okp->smk_known, 1701 &mkp->smk_rules); 1702 if (mmay == -ENOENT) { 1703 rc = -EACCES; 1704 break; 1705 } 1706 /* 1707 * If there is a local entry it modifies the 1708 * potential access, too. 1709 */ 1710 tmay = smk_access_entry(mkp->smk_known, okp->smk_known, 1711 &tsp->smk_rules); 1712 if (tmay != -ENOENT) 1713 mmay &= tmay; 1714 1715 /* 1716 * If there is any access available to current that is 1717 * not available to a SMACK64MMAP subject 1718 * deny access. 1719 */ 1720 if ((may | mmay) != mmay) { 1721 rc = -EACCES; 1722 break; 1723 } 1724 } 1725 1726 rcu_read_unlock(); 1727 1728 return rc; 1729 } 1730 1731 /** 1732 * smack_file_set_fowner - set the file security blob value 1733 * @file: object in question 1734 * 1735 */ 1736 static void smack_file_set_fowner(struct file *file) 1737 { 1738 struct smack_known **blob = smack_file(file); 1739 1740 *blob = smk_of_current(); 1741 } 1742 1743 /** 1744 * smack_file_send_sigiotask - Smack on sigio 1745 * @tsk: The target task 1746 * @fown: the object the signal come from 1747 * @signum: unused 1748 * 1749 * Allow a privileged task to get signals even if it shouldn't 1750 * 1751 * Returns 0 if a subject with the object's smack could 1752 * write to the task, an error code otherwise. 1753 */ 1754 static int smack_file_send_sigiotask(struct task_struct *tsk, 1755 struct fown_struct *fown, int signum) 1756 { 1757 struct smack_known **blob; 1758 struct smack_known *skp; 1759 struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred)); 1760 const struct cred *tcred; 1761 struct file *file; 1762 int rc; 1763 struct smk_audit_info ad; 1764 1765 /* 1766 * struct fown_struct is never outside the context of a struct file 1767 */ 1768 file = container_of(fown, struct file, f_owner); 1769 1770 /* we don't log here as rc can be overriden */ 1771 blob = smack_file(file); 1772 skp = *blob; 1773 rc = smk_access(skp, tkp, MAY_DELIVER, NULL); 1774 rc = smk_bu_note("sigiotask", skp, tkp, MAY_DELIVER, rc); 1775 1776 rcu_read_lock(); 1777 tcred = __task_cred(tsk); 1778 if (rc != 0 && smack_privileged_cred(CAP_MAC_OVERRIDE, tcred)) 1779 rc = 0; 1780 rcu_read_unlock(); 1781 1782 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); 1783 smk_ad_setfield_u_tsk(&ad, tsk); 1784 smack_log(skp->smk_known, tkp->smk_known, MAY_DELIVER, rc, &ad); 1785 return rc; 1786 } 1787 1788 /** 1789 * smack_file_receive - Smack file receive check 1790 * @file: the object 1791 * 1792 * Returns 0 if current has access, error code otherwise 1793 */ 1794 static int smack_file_receive(struct file *file) 1795 { 1796 int rc; 1797 int may = 0; 1798 struct smk_audit_info ad; 1799 struct inode *inode = file_inode(file); 1800 struct socket *sock; 1801 struct task_smack *tsp; 1802 struct socket_smack *ssp; 1803 1804 if (unlikely(IS_PRIVATE(inode))) 1805 return 0; 1806 1807 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1808 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1809 1810 if (inode->i_sb->s_magic == SOCKFS_MAGIC) { 1811 sock = SOCKET_I(inode); 1812 ssp = sock->sk->sk_security; 1813 tsp = smack_cred(current_cred()); 1814 /* 1815 * If the receiving process can't write to the 1816 * passed socket or if the passed socket can't 1817 * write to the receiving process don't accept 1818 * the passed socket. 1819 */ 1820 rc = smk_access(tsp->smk_task, ssp->smk_out, MAY_WRITE, &ad); 1821 rc = smk_bu_file(file, may, rc); 1822 if (rc < 0) 1823 return rc; 1824 rc = smk_access(ssp->smk_in, tsp->smk_task, MAY_WRITE, &ad); 1825 rc = smk_bu_file(file, may, rc); 1826 return rc; 1827 } 1828 /* 1829 * This code relies on bitmasks. 1830 */ 1831 if (file->f_mode & FMODE_READ) 1832 may = MAY_READ; 1833 if (file->f_mode & FMODE_WRITE) 1834 may |= MAY_WRITE; 1835 1836 rc = smk_curacc(smk_of_inode(inode), may, &ad); 1837 rc = smk_bu_file(file, may, rc); 1838 return rc; 1839 } 1840 1841 /** 1842 * smack_file_open - Smack dentry open processing 1843 * @file: the object 1844 * 1845 * Set the security blob in the file structure. 1846 * Allow the open only if the task has read access. There are 1847 * many read operations (e.g. fstat) that you can do with an 1848 * fd even if you have the file open write-only. 1849 * 1850 * Returns 0 if current has access, error code otherwise 1851 */ 1852 static int smack_file_open(struct file *file) 1853 { 1854 struct task_smack *tsp = smack_cred(file->f_cred); 1855 struct inode *inode = file_inode(file); 1856 struct smk_audit_info ad; 1857 int rc; 1858 1859 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 1860 smk_ad_setfield_u_fs_path(&ad, file->f_path); 1861 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad); 1862 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc); 1863 1864 return rc; 1865 } 1866 1867 /* 1868 * Task hooks 1869 */ 1870 1871 /** 1872 * smack_cred_alloc_blank - "allocate" blank task-level security credentials 1873 * @cred: the new credentials 1874 * @gfp: the atomicity of any memory allocations 1875 * 1876 * Prepare a blank set of credentials for modification. This must allocate all 1877 * the memory the LSM module might require such that cred_transfer() can 1878 * complete without error. 1879 */ 1880 static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) 1881 { 1882 init_task_smack(smack_cred(cred), NULL, NULL); 1883 return 0; 1884 } 1885 1886 1887 /** 1888 * smack_cred_free - "free" task-level security credentials 1889 * @cred: the credentials in question 1890 * 1891 */ 1892 static void smack_cred_free(struct cred *cred) 1893 { 1894 struct task_smack *tsp = smack_cred(cred); 1895 struct smack_rule *rp; 1896 struct list_head *l; 1897 struct list_head *n; 1898 1899 smk_destroy_label_list(&tsp->smk_relabel); 1900 1901 list_for_each_safe(l, n, &tsp->smk_rules) { 1902 rp = list_entry(l, struct smack_rule, list); 1903 list_del(&rp->list); 1904 kmem_cache_free(smack_rule_cache, rp); 1905 } 1906 } 1907 1908 /** 1909 * smack_cred_prepare - prepare new set of credentials for modification 1910 * @new: the new credentials 1911 * @old: the original credentials 1912 * @gfp: the atomicity of any memory allocations 1913 * 1914 * Prepare a new set of credentials for modification. 1915 */ 1916 static int smack_cred_prepare(struct cred *new, const struct cred *old, 1917 gfp_t gfp) 1918 { 1919 struct task_smack *old_tsp = smack_cred(old); 1920 struct task_smack *new_tsp = smack_cred(new); 1921 int rc; 1922 1923 init_task_smack(new_tsp, old_tsp->smk_task, old_tsp->smk_task); 1924 1925 rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp); 1926 if (rc != 0) 1927 return rc; 1928 1929 rc = smk_copy_relabel(&new_tsp->smk_relabel, &old_tsp->smk_relabel, 1930 gfp); 1931 return rc; 1932 } 1933 1934 /** 1935 * smack_cred_transfer - Transfer the old credentials to the new credentials 1936 * @new: the new credentials 1937 * @old: the original credentials 1938 * 1939 * Fill in a set of blank credentials from another set of credentials. 1940 */ 1941 static void smack_cred_transfer(struct cred *new, const struct cred *old) 1942 { 1943 struct task_smack *old_tsp = smack_cred(old); 1944 struct task_smack *new_tsp = smack_cred(new); 1945 1946 new_tsp->smk_task = old_tsp->smk_task; 1947 new_tsp->smk_forked = old_tsp->smk_task; 1948 mutex_init(&new_tsp->smk_rules_lock); 1949 INIT_LIST_HEAD(&new_tsp->smk_rules); 1950 1951 /* cbs copy rule list */ 1952 } 1953 1954 /** 1955 * smack_cred_getsecid - get the secid corresponding to a creds structure 1956 * @cred: the object creds 1957 * @secid: where to put the result 1958 * 1959 * Sets the secid to contain a u32 version of the smack label. 1960 */ 1961 static void smack_cred_getsecid(const struct cred *cred, u32 *secid) 1962 { 1963 struct smack_known *skp; 1964 1965 rcu_read_lock(); 1966 skp = smk_of_task(smack_cred(cred)); 1967 *secid = skp->smk_secid; 1968 rcu_read_unlock(); 1969 } 1970 1971 /** 1972 * smack_kernel_act_as - Set the subjective context in a set of credentials 1973 * @new: points to the set of credentials to be modified. 1974 * @secid: specifies the security ID to be set 1975 * 1976 * Set the security data for a kernel service. 1977 */ 1978 static int smack_kernel_act_as(struct cred *new, u32 secid) 1979 { 1980 struct task_smack *new_tsp = smack_cred(new); 1981 1982 new_tsp->smk_task = smack_from_secid(secid); 1983 return 0; 1984 } 1985 1986 /** 1987 * smack_kernel_create_files_as - Set the file creation label in a set of creds 1988 * @new: points to the set of credentials to be modified 1989 * @inode: points to the inode to use as a reference 1990 * 1991 * Set the file creation context in a set of credentials to the same 1992 * as the objective context of the specified inode 1993 */ 1994 static int smack_kernel_create_files_as(struct cred *new, 1995 struct inode *inode) 1996 { 1997 struct inode_smack *isp = smack_inode(inode); 1998 struct task_smack *tsp = smack_cred(new); 1999 2000 tsp->smk_forked = isp->smk_inode; 2001 tsp->smk_task = tsp->smk_forked; 2002 return 0; 2003 } 2004 2005 /** 2006 * smk_curacc_on_task - helper to log task related access 2007 * @p: the task object 2008 * @access: the access requested 2009 * @caller: name of the calling function for audit 2010 * 2011 * Return 0 if access is permitted 2012 */ 2013 static int smk_curacc_on_task(struct task_struct *p, int access, 2014 const char *caller) 2015 { 2016 struct smk_audit_info ad; 2017 struct smack_known *skp = smk_of_task_struct_obj(p); 2018 int rc; 2019 2020 smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK); 2021 smk_ad_setfield_u_tsk(&ad, p); 2022 rc = smk_curacc(skp, access, &ad); 2023 rc = smk_bu_task(p, access, rc); 2024 return rc; 2025 } 2026 2027 /** 2028 * smack_task_setpgid - Smack check on setting pgid 2029 * @p: the task object 2030 * @pgid: unused 2031 * 2032 * Return 0 if write access is permitted 2033 */ 2034 static int smack_task_setpgid(struct task_struct *p, pid_t pgid) 2035 { 2036 return smk_curacc_on_task(p, MAY_WRITE, __func__); 2037 } 2038 2039 /** 2040 * smack_task_getpgid - Smack access check for getpgid 2041 * @p: the object task 2042 * 2043 * Returns 0 if current can read the object task, error code otherwise 2044 */ 2045 static int smack_task_getpgid(struct task_struct *p) 2046 { 2047 return smk_curacc_on_task(p, MAY_READ, __func__); 2048 } 2049 2050 /** 2051 * smack_task_getsid - Smack access check for getsid 2052 * @p: the object task 2053 * 2054 * Returns 0 if current can read the object task, error code otherwise 2055 */ 2056 static int smack_task_getsid(struct task_struct *p) 2057 { 2058 return smk_curacc_on_task(p, MAY_READ, __func__); 2059 } 2060 2061 /** 2062 * smack_current_getsecid_subj - get the subjective secid of the current task 2063 * @secid: where to put the result 2064 * 2065 * Sets the secid to contain a u32 version of the task's subjective smack label. 2066 */ 2067 static void smack_current_getsecid_subj(u32 *secid) 2068 { 2069 struct smack_known *skp = smk_of_current(); 2070 2071 *secid = skp->smk_secid; 2072 } 2073 2074 /** 2075 * smack_task_getsecid_obj - get the objective secid of the task 2076 * @p: the task 2077 * @secid: where to put the result 2078 * 2079 * Sets the secid to contain a u32 version of the task's objective smack label. 2080 */ 2081 static void smack_task_getsecid_obj(struct task_struct *p, u32 *secid) 2082 { 2083 struct smack_known *skp = smk_of_task_struct_obj(p); 2084 2085 *secid = skp->smk_secid; 2086 } 2087 2088 /** 2089 * smack_task_setnice - Smack check on setting nice 2090 * @p: the task object 2091 * @nice: unused 2092 * 2093 * Return 0 if write access is permitted 2094 */ 2095 static int smack_task_setnice(struct task_struct *p, int nice) 2096 { 2097 return smk_curacc_on_task(p, MAY_WRITE, __func__); 2098 } 2099 2100 /** 2101 * smack_task_setioprio - Smack check on setting ioprio 2102 * @p: the task object 2103 * @ioprio: unused 2104 * 2105 * Return 0 if write access is permitted 2106 */ 2107 static int smack_task_setioprio(struct task_struct *p, int ioprio) 2108 { 2109 return smk_curacc_on_task(p, MAY_WRITE, __func__); 2110 } 2111 2112 /** 2113 * smack_task_getioprio - Smack check on reading ioprio 2114 * @p: the task object 2115 * 2116 * Return 0 if read access is permitted 2117 */ 2118 static int smack_task_getioprio(struct task_struct *p) 2119 { 2120 return smk_curacc_on_task(p, MAY_READ, __func__); 2121 } 2122 2123 /** 2124 * smack_task_setscheduler - Smack check on setting scheduler 2125 * @p: the task object 2126 * 2127 * Return 0 if read access is permitted 2128 */ 2129 static int smack_task_setscheduler(struct task_struct *p) 2130 { 2131 return smk_curacc_on_task(p, MAY_WRITE, __func__); 2132 } 2133 2134 /** 2135 * smack_task_getscheduler - Smack check on reading scheduler 2136 * @p: the task object 2137 * 2138 * Return 0 if read access is permitted 2139 */ 2140 static int smack_task_getscheduler(struct task_struct *p) 2141 { 2142 return smk_curacc_on_task(p, MAY_READ, __func__); 2143 } 2144 2145 /** 2146 * smack_task_movememory - Smack check on moving memory 2147 * @p: the task object 2148 * 2149 * Return 0 if write access is permitted 2150 */ 2151 static int smack_task_movememory(struct task_struct *p) 2152 { 2153 return smk_curacc_on_task(p, MAY_WRITE, __func__); 2154 } 2155 2156 /** 2157 * smack_task_kill - Smack check on signal delivery 2158 * @p: the task object 2159 * @info: unused 2160 * @sig: unused 2161 * @cred: identifies the cred to use in lieu of current's 2162 * 2163 * Return 0 if write access is permitted 2164 * 2165 */ 2166 static int smack_task_kill(struct task_struct *p, struct kernel_siginfo *info, 2167 int sig, const struct cred *cred) 2168 { 2169 struct smk_audit_info ad; 2170 struct smack_known *skp; 2171 struct smack_known *tkp = smk_of_task_struct_obj(p); 2172 int rc; 2173 2174 if (!sig) 2175 return 0; /* null signal; existence test */ 2176 2177 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); 2178 smk_ad_setfield_u_tsk(&ad, p); 2179 /* 2180 * Sending a signal requires that the sender 2181 * can write the receiver. 2182 */ 2183 if (cred == NULL) { 2184 rc = smk_curacc(tkp, MAY_DELIVER, &ad); 2185 rc = smk_bu_task(p, MAY_DELIVER, rc); 2186 return rc; 2187 } 2188 /* 2189 * If the cred isn't NULL we're dealing with some USB IO 2190 * specific behavior. This is not clean. For one thing 2191 * we can't take privilege into account. 2192 */ 2193 skp = smk_of_task(smack_cred(cred)); 2194 rc = smk_access(skp, tkp, MAY_DELIVER, &ad); 2195 rc = smk_bu_note("USB signal", skp, tkp, MAY_DELIVER, rc); 2196 return rc; 2197 } 2198 2199 /** 2200 * smack_task_to_inode - copy task smack into the inode blob 2201 * @p: task to copy from 2202 * @inode: inode to copy to 2203 * 2204 * Sets the smack pointer in the inode security blob 2205 */ 2206 static void smack_task_to_inode(struct task_struct *p, struct inode *inode) 2207 { 2208 struct inode_smack *isp = smack_inode(inode); 2209 struct smack_known *skp = smk_of_task_struct_obj(p); 2210 2211 isp->smk_inode = skp; 2212 isp->smk_flags |= SMK_INODE_INSTANT; 2213 } 2214 2215 /* 2216 * Socket hooks. 2217 */ 2218 2219 /** 2220 * smack_sk_alloc_security - Allocate a socket blob 2221 * @sk: the socket 2222 * @family: unused 2223 * @gfp_flags: memory allocation flags 2224 * 2225 * Assign Smack pointers to current 2226 * 2227 * Returns 0 on success, -ENOMEM is there's no memory 2228 */ 2229 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) 2230 { 2231 struct smack_known *skp = smk_of_current(); 2232 struct socket_smack *ssp; 2233 2234 ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); 2235 if (ssp == NULL) 2236 return -ENOMEM; 2237 2238 /* 2239 * Sockets created by kernel threads receive web label. 2240 */ 2241 if (unlikely(current->flags & PF_KTHREAD)) { 2242 ssp->smk_in = &smack_known_web; 2243 ssp->smk_out = &smack_known_web; 2244 } else { 2245 ssp->smk_in = skp; 2246 ssp->smk_out = skp; 2247 } 2248 ssp->smk_packet = NULL; 2249 2250 sk->sk_security = ssp; 2251 2252 return 0; 2253 } 2254 2255 /** 2256 * smack_sk_free_security - Free a socket blob 2257 * @sk: the socket 2258 * 2259 * Clears the blob pointer 2260 */ 2261 static void smack_sk_free_security(struct sock *sk) 2262 { 2263 #ifdef SMACK_IPV6_PORT_LABELING 2264 struct smk_port_label *spp; 2265 2266 if (sk->sk_family == PF_INET6) { 2267 rcu_read_lock(); 2268 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) { 2269 if (spp->smk_sock != sk) 2270 continue; 2271 spp->smk_can_reuse = 1; 2272 break; 2273 } 2274 rcu_read_unlock(); 2275 } 2276 #endif 2277 kfree(sk->sk_security); 2278 } 2279 2280 /** 2281 * smack_sk_clone_security - Copy security context 2282 * @sk: the old socket 2283 * @newsk: the new socket 2284 * 2285 * Copy the security context of the old socket pointer to the cloned 2286 */ 2287 static void smack_sk_clone_security(const struct sock *sk, struct sock *newsk) 2288 { 2289 struct socket_smack *ssp_old = sk->sk_security; 2290 struct socket_smack *ssp_new = newsk->sk_security; 2291 2292 *ssp_new = *ssp_old; 2293 } 2294 2295 /** 2296 * smack_ipv4host_label - check host based restrictions 2297 * @sip: the object end 2298 * 2299 * looks for host based access restrictions 2300 * 2301 * This version will only be appropriate for really small sets of single label 2302 * hosts. The caller is responsible for ensuring that the RCU read lock is 2303 * taken before calling this function. 2304 * 2305 * Returns the label of the far end or NULL if it's not special. 2306 */ 2307 static struct smack_known *smack_ipv4host_label(struct sockaddr_in *sip) 2308 { 2309 struct smk_net4addr *snp; 2310 struct in_addr *siap = &sip->sin_addr; 2311 2312 if (siap->s_addr == 0) 2313 return NULL; 2314 2315 list_for_each_entry_rcu(snp, &smk_net4addr_list, list) 2316 /* 2317 * we break after finding the first match because 2318 * the list is sorted from longest to shortest mask 2319 * so we have found the most specific match 2320 */ 2321 if (snp->smk_host.s_addr == 2322 (siap->s_addr & snp->smk_mask.s_addr)) 2323 return snp->smk_label; 2324 2325 return NULL; 2326 } 2327 2328 /* 2329 * smk_ipv6_localhost - Check for local ipv6 host address 2330 * @sip: the address 2331 * 2332 * Returns boolean true if this is the localhost address 2333 */ 2334 static bool smk_ipv6_localhost(struct sockaddr_in6 *sip) 2335 { 2336 __be16 *be16p = (__be16 *)&sip->sin6_addr; 2337 __be32 *be32p = (__be32 *)&sip->sin6_addr; 2338 2339 if (be32p[0] == 0 && be32p[1] == 0 && be32p[2] == 0 && be16p[6] == 0 && 2340 ntohs(be16p[7]) == 1) 2341 return true; 2342 return false; 2343 } 2344 2345 /** 2346 * smack_ipv6host_label - check host based restrictions 2347 * @sip: the object end 2348 * 2349 * looks for host based access restrictions 2350 * 2351 * This version will only be appropriate for really small sets of single label 2352 * hosts. The caller is responsible for ensuring that the RCU read lock is 2353 * taken before calling this function. 2354 * 2355 * Returns the label of the far end or NULL if it's not special. 2356 */ 2357 static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip) 2358 { 2359 struct smk_net6addr *snp; 2360 struct in6_addr *sap = &sip->sin6_addr; 2361 int i; 2362 int found = 0; 2363 2364 /* 2365 * It's local. Don't look for a host label. 2366 */ 2367 if (smk_ipv6_localhost(sip)) 2368 return NULL; 2369 2370 list_for_each_entry_rcu(snp, &smk_net6addr_list, list) { 2371 /* 2372 * If the label is NULL the entry has 2373 * been renounced. Ignore it. 2374 */ 2375 if (snp->smk_label == NULL) 2376 continue; 2377 /* 2378 * we break after finding the first match because 2379 * the list is sorted from longest to shortest mask 2380 * so we have found the most specific match 2381 */ 2382 for (found = 1, i = 0; i < 8; i++) { 2383 if ((sap->s6_addr16[i] & snp->smk_mask.s6_addr16[i]) != 2384 snp->smk_host.s6_addr16[i]) { 2385 found = 0; 2386 break; 2387 } 2388 } 2389 if (found) 2390 return snp->smk_label; 2391 } 2392 2393 return NULL; 2394 } 2395 2396 /** 2397 * smack_netlbl_add - Set the secattr on a socket 2398 * @sk: the socket 2399 * 2400 * Attach the outbound smack value (smk_out) to the socket. 2401 * 2402 * Returns 0 on success or an error code 2403 */ 2404 static int smack_netlbl_add(struct sock *sk) 2405 { 2406 struct socket_smack *ssp = sk->sk_security; 2407 struct smack_known *skp = ssp->smk_out; 2408 int rc; 2409 2410 local_bh_disable(); 2411 bh_lock_sock_nested(sk); 2412 2413 rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel); 2414 switch (rc) { 2415 case 0: 2416 ssp->smk_state = SMK_NETLBL_LABELED; 2417 break; 2418 case -EDESTADDRREQ: 2419 ssp->smk_state = SMK_NETLBL_REQSKB; 2420 rc = 0; 2421 break; 2422 } 2423 2424 bh_unlock_sock(sk); 2425 local_bh_enable(); 2426 2427 return rc; 2428 } 2429 2430 /** 2431 * smack_netlbl_delete - Remove the secattr from a socket 2432 * @sk: the socket 2433 * 2434 * Remove the outbound smack value from a socket 2435 */ 2436 static void smack_netlbl_delete(struct sock *sk) 2437 { 2438 struct socket_smack *ssp = sk->sk_security; 2439 2440 /* 2441 * Take the label off the socket if one is set. 2442 */ 2443 if (ssp->smk_state != SMK_NETLBL_LABELED) 2444 return; 2445 2446 local_bh_disable(); 2447 bh_lock_sock_nested(sk); 2448 netlbl_sock_delattr(sk); 2449 bh_unlock_sock(sk); 2450 local_bh_enable(); 2451 ssp->smk_state = SMK_NETLBL_UNLABELED; 2452 } 2453 2454 /** 2455 * smk_ipv4_check - Perform IPv4 host access checks 2456 * @sk: the socket 2457 * @sap: the destination address 2458 * 2459 * Set the correct secattr for the given socket based on the destination 2460 * address and perform any outbound access checks needed. 2461 * 2462 * Returns 0 on success or an error code. 2463 * 2464 */ 2465 static int smk_ipv4_check(struct sock *sk, struct sockaddr_in *sap) 2466 { 2467 struct smack_known *skp; 2468 int rc = 0; 2469 struct smack_known *hkp; 2470 struct socket_smack *ssp = sk->sk_security; 2471 struct smk_audit_info ad; 2472 2473 rcu_read_lock(); 2474 hkp = smack_ipv4host_label(sap); 2475 if (hkp != NULL) { 2476 #ifdef CONFIG_AUDIT 2477 struct lsm_network_audit net; 2478 2479 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 2480 ad.a.u.net->family = sap->sin_family; 2481 ad.a.u.net->dport = sap->sin_port; 2482 ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr; 2483 #endif 2484 skp = ssp->smk_out; 2485 rc = smk_access(skp, hkp, MAY_WRITE, &ad); 2486 rc = smk_bu_note("IPv4 host check", skp, hkp, MAY_WRITE, rc); 2487 /* 2488 * Clear the socket netlabel if it's set. 2489 */ 2490 if (!rc) 2491 smack_netlbl_delete(sk); 2492 } 2493 rcu_read_unlock(); 2494 2495 return rc; 2496 } 2497 2498 /** 2499 * smk_ipv6_check - check Smack access 2500 * @subject: subject Smack label 2501 * @object: object Smack label 2502 * @address: address 2503 * @act: the action being taken 2504 * 2505 * Check an IPv6 access 2506 */ 2507 static int smk_ipv6_check(struct smack_known *subject, 2508 struct smack_known *object, 2509 struct sockaddr_in6 *address, int act) 2510 { 2511 #ifdef CONFIG_AUDIT 2512 struct lsm_network_audit net; 2513 #endif 2514 struct smk_audit_info ad; 2515 int rc; 2516 2517 #ifdef CONFIG_AUDIT 2518 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 2519 ad.a.u.net->family = PF_INET6; 2520 ad.a.u.net->dport = address->sin6_port; 2521 if (act == SMK_RECEIVING) 2522 ad.a.u.net->v6info.saddr = address->sin6_addr; 2523 else 2524 ad.a.u.net->v6info.daddr = address->sin6_addr; 2525 #endif 2526 rc = smk_access(subject, object, MAY_WRITE, &ad); 2527 rc = smk_bu_note("IPv6 check", subject, object, MAY_WRITE, rc); 2528 return rc; 2529 } 2530 2531 #ifdef SMACK_IPV6_PORT_LABELING 2532 /** 2533 * smk_ipv6_port_label - Smack port access table management 2534 * @sock: socket 2535 * @address: address 2536 * 2537 * Create or update the port list entry 2538 */ 2539 static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address) 2540 { 2541 struct sock *sk = sock->sk; 2542 struct sockaddr_in6 *addr6; 2543 struct socket_smack *ssp = sock->sk->sk_security; 2544 struct smk_port_label *spp; 2545 unsigned short port = 0; 2546 2547 if (address == NULL) { 2548 /* 2549 * This operation is changing the Smack information 2550 * on the bound socket. Take the changes to the port 2551 * as well. 2552 */ 2553 rcu_read_lock(); 2554 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) { 2555 if (sk != spp->smk_sock) 2556 continue; 2557 spp->smk_in = ssp->smk_in; 2558 spp->smk_out = ssp->smk_out; 2559 rcu_read_unlock(); 2560 return; 2561 } 2562 /* 2563 * A NULL address is only used for updating existing 2564 * bound entries. If there isn't one, it's OK. 2565 */ 2566 rcu_read_unlock(); 2567 return; 2568 } 2569 2570 addr6 = (struct sockaddr_in6 *)address; 2571 port = ntohs(addr6->sin6_port); 2572 /* 2573 * This is a special case that is safely ignored. 2574 */ 2575 if (port == 0) 2576 return; 2577 2578 /* 2579 * Look for an existing port list entry. 2580 * This is an indication that a port is getting reused. 2581 */ 2582 rcu_read_lock(); 2583 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) { 2584 if (spp->smk_port != port || spp->smk_sock_type != sock->type) 2585 continue; 2586 if (spp->smk_can_reuse != 1) { 2587 rcu_read_unlock(); 2588 return; 2589 } 2590 spp->smk_port = port; 2591 spp->smk_sock = sk; 2592 spp->smk_in = ssp->smk_in; 2593 spp->smk_out = ssp->smk_out; 2594 spp->smk_can_reuse = 0; 2595 rcu_read_unlock(); 2596 return; 2597 } 2598 rcu_read_unlock(); 2599 /* 2600 * A new port entry is required. 2601 */ 2602 spp = kzalloc(sizeof(*spp), GFP_KERNEL); 2603 if (spp == NULL) 2604 return; 2605 2606 spp->smk_port = port; 2607 spp->smk_sock = sk; 2608 spp->smk_in = ssp->smk_in; 2609 spp->smk_out = ssp->smk_out; 2610 spp->smk_sock_type = sock->type; 2611 spp->smk_can_reuse = 0; 2612 2613 mutex_lock(&smack_ipv6_lock); 2614 list_add_rcu(&spp->list, &smk_ipv6_port_list); 2615 mutex_unlock(&smack_ipv6_lock); 2616 return; 2617 } 2618 2619 /** 2620 * smk_ipv6_port_check - check Smack port access 2621 * @sk: socket 2622 * @address: address 2623 * @act: the action being taken 2624 * 2625 * Create or update the port list entry 2626 */ 2627 static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address, 2628 int act) 2629 { 2630 struct smk_port_label *spp; 2631 struct socket_smack *ssp = sk->sk_security; 2632 struct smack_known *skp = NULL; 2633 unsigned short port; 2634 struct smack_known *object; 2635 2636 if (act == SMK_RECEIVING) { 2637 skp = smack_ipv6host_label(address); 2638 object = ssp->smk_in; 2639 } else { 2640 skp = ssp->smk_out; 2641 object = smack_ipv6host_label(address); 2642 } 2643 2644 /* 2645 * The other end is a single label host. 2646 */ 2647 if (skp != NULL && object != NULL) 2648 return smk_ipv6_check(skp, object, address, act); 2649 if (skp == NULL) 2650 skp = smack_net_ambient; 2651 if (object == NULL) 2652 object = smack_net_ambient; 2653 2654 /* 2655 * It's remote, so port lookup does no good. 2656 */ 2657 if (!smk_ipv6_localhost(address)) 2658 return smk_ipv6_check(skp, object, address, act); 2659 2660 /* 2661 * It's local so the send check has to have passed. 2662 */ 2663 if (act == SMK_RECEIVING) 2664 return 0; 2665 2666 port = ntohs(address->sin6_port); 2667 rcu_read_lock(); 2668 list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) { 2669 if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type) 2670 continue; 2671 object = spp->smk_in; 2672 if (act == SMK_CONNECTING) 2673 ssp->smk_packet = spp->smk_out; 2674 break; 2675 } 2676 rcu_read_unlock(); 2677 2678 return smk_ipv6_check(skp, object, address, act); 2679 } 2680 #endif 2681 2682 /** 2683 * smack_inode_setsecurity - set smack xattrs 2684 * @inode: the object 2685 * @name: attribute name 2686 * @value: attribute value 2687 * @size: size of the attribute 2688 * @flags: unused 2689 * 2690 * Sets the named attribute in the appropriate blob 2691 * 2692 * Returns 0 on success, or an error code 2693 */ 2694 static int smack_inode_setsecurity(struct inode *inode, const char *name, 2695 const void *value, size_t size, int flags) 2696 { 2697 struct smack_known *skp; 2698 struct inode_smack *nsp = smack_inode(inode); 2699 struct socket_smack *ssp; 2700 struct socket *sock; 2701 int rc = 0; 2702 2703 if (value == NULL || size > SMK_LONGLABEL || size == 0) 2704 return -EINVAL; 2705 2706 skp = smk_import_entry(value, size); 2707 if (IS_ERR(skp)) 2708 return PTR_ERR(skp); 2709 2710 if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { 2711 nsp->smk_inode = skp; 2712 nsp->smk_flags |= SMK_INODE_INSTANT; 2713 return 0; 2714 } 2715 /* 2716 * The rest of the Smack xattrs are only on sockets. 2717 */ 2718 if (inode->i_sb->s_magic != SOCKFS_MAGIC) 2719 return -EOPNOTSUPP; 2720 2721 sock = SOCKET_I(inode); 2722 if (sock == NULL || sock->sk == NULL) 2723 return -EOPNOTSUPP; 2724 2725 ssp = sock->sk->sk_security; 2726 2727 if (strcmp(name, XATTR_SMACK_IPIN) == 0) 2728 ssp->smk_in = skp; 2729 else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { 2730 ssp->smk_out = skp; 2731 if (sock->sk->sk_family == PF_INET) { 2732 rc = smack_netlbl_add(sock->sk); 2733 if (rc != 0) 2734 printk(KERN_WARNING 2735 "Smack: \"%s\" netlbl error %d.\n", 2736 __func__, -rc); 2737 } 2738 } else 2739 return -EOPNOTSUPP; 2740 2741 #ifdef SMACK_IPV6_PORT_LABELING 2742 if (sock->sk->sk_family == PF_INET6) 2743 smk_ipv6_port_label(sock, NULL); 2744 #endif 2745 2746 return 0; 2747 } 2748 2749 /** 2750 * smack_socket_post_create - finish socket setup 2751 * @sock: the socket 2752 * @family: protocol family 2753 * @type: unused 2754 * @protocol: unused 2755 * @kern: unused 2756 * 2757 * Sets the netlabel information on the socket 2758 * 2759 * Returns 0 on success, and error code otherwise 2760 */ 2761 static int smack_socket_post_create(struct socket *sock, int family, 2762 int type, int protocol, int kern) 2763 { 2764 struct socket_smack *ssp; 2765 2766 if (sock->sk == NULL) 2767 return 0; 2768 2769 /* 2770 * Sockets created by kernel threads receive web label. 2771 */ 2772 if (unlikely(current->flags & PF_KTHREAD)) { 2773 ssp = sock->sk->sk_security; 2774 ssp->smk_in = &smack_known_web; 2775 ssp->smk_out = &smack_known_web; 2776 } 2777 2778 if (family != PF_INET) 2779 return 0; 2780 /* 2781 * Set the outbound netlbl. 2782 */ 2783 return smack_netlbl_add(sock->sk); 2784 } 2785 2786 /** 2787 * smack_socket_socketpair - create socket pair 2788 * @socka: one socket 2789 * @sockb: another socket 2790 * 2791 * Cross reference the peer labels for SO_PEERSEC 2792 * 2793 * Returns 0 2794 */ 2795 static int smack_socket_socketpair(struct socket *socka, 2796 struct socket *sockb) 2797 { 2798 struct socket_smack *asp = socka->sk->sk_security; 2799 struct socket_smack *bsp = sockb->sk->sk_security; 2800 2801 asp->smk_packet = bsp->smk_out; 2802 bsp->smk_packet = asp->smk_out; 2803 2804 return 0; 2805 } 2806 2807 #ifdef SMACK_IPV6_PORT_LABELING 2808 /** 2809 * smack_socket_bind - record port binding information. 2810 * @sock: the socket 2811 * @address: the port address 2812 * @addrlen: size of the address 2813 * 2814 * Records the label bound to a port. 2815 * 2816 * Returns 0 on success, and error code otherwise 2817 */ 2818 static int smack_socket_bind(struct socket *sock, struct sockaddr *address, 2819 int addrlen) 2820 { 2821 if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) { 2822 if (addrlen < SIN6_LEN_RFC2133 || 2823 address->sa_family != AF_INET6) 2824 return -EINVAL; 2825 smk_ipv6_port_label(sock, address); 2826 } 2827 return 0; 2828 } 2829 #endif /* SMACK_IPV6_PORT_LABELING */ 2830 2831 /** 2832 * smack_socket_connect - connect access check 2833 * @sock: the socket 2834 * @sap: the other end 2835 * @addrlen: size of sap 2836 * 2837 * Verifies that a connection may be possible 2838 * 2839 * Returns 0 on success, and error code otherwise 2840 */ 2841 static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, 2842 int addrlen) 2843 { 2844 int rc = 0; 2845 2846 if (sock->sk == NULL) 2847 return 0; 2848 if (sock->sk->sk_family != PF_INET && 2849 (!IS_ENABLED(CONFIG_IPV6) || sock->sk->sk_family != PF_INET6)) 2850 return 0; 2851 if (addrlen < offsetofend(struct sockaddr, sa_family)) 2852 return 0; 2853 if (IS_ENABLED(CONFIG_IPV6) && sap->sa_family == AF_INET6) { 2854 struct sockaddr_in6 *sip = (struct sockaddr_in6 *)sap; 2855 struct smack_known *rsp = NULL; 2856 2857 if (addrlen < SIN6_LEN_RFC2133) 2858 return 0; 2859 if (__is_defined(SMACK_IPV6_SECMARK_LABELING)) 2860 rsp = smack_ipv6host_label(sip); 2861 if (rsp != NULL) { 2862 struct socket_smack *ssp = sock->sk->sk_security; 2863 2864 rc = smk_ipv6_check(ssp->smk_out, rsp, sip, 2865 SMK_CONNECTING); 2866 } 2867 #ifdef SMACK_IPV6_PORT_LABELING 2868 rc = smk_ipv6_port_check(sock->sk, sip, SMK_CONNECTING); 2869 #endif 2870 2871 return rc; 2872 } 2873 if (sap->sa_family != AF_INET || addrlen < sizeof(struct sockaddr_in)) 2874 return 0; 2875 rc = smk_ipv4_check(sock->sk, (struct sockaddr_in *)sap); 2876 return rc; 2877 } 2878 2879 /** 2880 * smack_flags_to_may - convert S_ to MAY_ values 2881 * @flags: the S_ value 2882 * 2883 * Returns the equivalent MAY_ value 2884 */ 2885 static int smack_flags_to_may(int flags) 2886 { 2887 int may = 0; 2888 2889 if (flags & S_IRUGO) 2890 may |= MAY_READ; 2891 if (flags & S_IWUGO) 2892 may |= MAY_WRITE; 2893 if (flags & S_IXUGO) 2894 may |= MAY_EXEC; 2895 2896 return may; 2897 } 2898 2899 /** 2900 * smack_msg_msg_alloc_security - Set the security blob for msg_msg 2901 * @msg: the object 2902 * 2903 * Returns 0 2904 */ 2905 static int smack_msg_msg_alloc_security(struct msg_msg *msg) 2906 { 2907 struct smack_known **blob = smack_msg_msg(msg); 2908 2909 *blob = smk_of_current(); 2910 return 0; 2911 } 2912 2913 /** 2914 * smack_of_ipc - the smack pointer for the ipc 2915 * @isp: the object 2916 * 2917 * Returns a pointer to the smack value 2918 */ 2919 static struct smack_known *smack_of_ipc(struct kern_ipc_perm *isp) 2920 { 2921 struct smack_known **blob = smack_ipc(isp); 2922 2923 return *blob; 2924 } 2925 2926 /** 2927 * smack_ipc_alloc_security - Set the security blob for ipc 2928 * @isp: the object 2929 * 2930 * Returns 0 2931 */ 2932 static int smack_ipc_alloc_security(struct kern_ipc_perm *isp) 2933 { 2934 struct smack_known **blob = smack_ipc(isp); 2935 2936 *blob = smk_of_current(); 2937 return 0; 2938 } 2939 2940 /** 2941 * smk_curacc_shm : check if current has access on shm 2942 * @isp : the object 2943 * @access : access requested 2944 * 2945 * Returns 0 if current has the requested access, error code otherwise 2946 */ 2947 static int smk_curacc_shm(struct kern_ipc_perm *isp, int access) 2948 { 2949 struct smack_known *ssp = smack_of_ipc(isp); 2950 struct smk_audit_info ad; 2951 int rc; 2952 2953 #ifdef CONFIG_AUDIT 2954 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); 2955 ad.a.u.ipc_id = isp->id; 2956 #endif 2957 rc = smk_curacc(ssp, access, &ad); 2958 rc = smk_bu_current("shm", ssp, access, rc); 2959 return rc; 2960 } 2961 2962 /** 2963 * smack_shm_associate - Smack access check for shm 2964 * @isp: the object 2965 * @shmflg: access requested 2966 * 2967 * Returns 0 if current has the requested access, error code otherwise 2968 */ 2969 static int smack_shm_associate(struct kern_ipc_perm *isp, int shmflg) 2970 { 2971 int may; 2972 2973 may = smack_flags_to_may(shmflg); 2974 return smk_curacc_shm(isp, may); 2975 } 2976 2977 /** 2978 * smack_shm_shmctl - Smack access check for shm 2979 * @isp: the object 2980 * @cmd: what it wants to do 2981 * 2982 * Returns 0 if current has the requested access, error code otherwise 2983 */ 2984 static int smack_shm_shmctl(struct kern_ipc_perm *isp, int cmd) 2985 { 2986 int may; 2987 2988 switch (cmd) { 2989 case IPC_STAT: 2990 case SHM_STAT: 2991 case SHM_STAT_ANY: 2992 may = MAY_READ; 2993 break; 2994 case IPC_SET: 2995 case SHM_LOCK: 2996 case SHM_UNLOCK: 2997 case IPC_RMID: 2998 may = MAY_READWRITE; 2999 break; 3000 case IPC_INFO: 3001 case SHM_INFO: 3002 /* 3003 * System level information. 3004 */ 3005 return 0; 3006 default: 3007 return -EINVAL; 3008 } 3009 return smk_curacc_shm(isp, may); 3010 } 3011 3012 /** 3013 * smack_shm_shmat - Smack access for shmat 3014 * @isp: the object 3015 * @shmaddr: unused 3016 * @shmflg: access requested 3017 * 3018 * Returns 0 if current has the requested access, error code otherwise 3019 */ 3020 static int smack_shm_shmat(struct kern_ipc_perm *isp, char __user *shmaddr, 3021 int shmflg) 3022 { 3023 int may; 3024 3025 may = smack_flags_to_may(shmflg); 3026 return smk_curacc_shm(isp, may); 3027 } 3028 3029 /** 3030 * smk_curacc_sem : check if current has access on sem 3031 * @isp : the object 3032 * @access : access requested 3033 * 3034 * Returns 0 if current has the requested access, error code otherwise 3035 */ 3036 static int smk_curacc_sem(struct kern_ipc_perm *isp, int access) 3037 { 3038 struct smack_known *ssp = smack_of_ipc(isp); 3039 struct smk_audit_info ad; 3040 int rc; 3041 3042 #ifdef CONFIG_AUDIT 3043 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); 3044 ad.a.u.ipc_id = isp->id; 3045 #endif 3046 rc = smk_curacc(ssp, access, &ad); 3047 rc = smk_bu_current("sem", ssp, access, rc); 3048 return rc; 3049 } 3050 3051 /** 3052 * smack_sem_associate - Smack access check for sem 3053 * @isp: the object 3054 * @semflg: access requested 3055 * 3056 * Returns 0 if current has the requested access, error code otherwise 3057 */ 3058 static int smack_sem_associate(struct kern_ipc_perm *isp, int semflg) 3059 { 3060 int may; 3061 3062 may = smack_flags_to_may(semflg); 3063 return smk_curacc_sem(isp, may); 3064 } 3065 3066 /** 3067 * smack_sem_semctl - Smack access check for sem 3068 * @isp: the object 3069 * @cmd: what it wants to do 3070 * 3071 * Returns 0 if current has the requested access, error code otherwise 3072 */ 3073 static int smack_sem_semctl(struct kern_ipc_perm *isp, int cmd) 3074 { 3075 int may; 3076 3077 switch (cmd) { 3078 case GETPID: 3079 case GETNCNT: 3080 case GETZCNT: 3081 case GETVAL: 3082 case GETALL: 3083 case IPC_STAT: 3084 case SEM_STAT: 3085 case SEM_STAT_ANY: 3086 may = MAY_READ; 3087 break; 3088 case SETVAL: 3089 case SETALL: 3090 case IPC_RMID: 3091 case IPC_SET: 3092 may = MAY_READWRITE; 3093 break; 3094 case IPC_INFO: 3095 case SEM_INFO: 3096 /* 3097 * System level information 3098 */ 3099 return 0; 3100 default: 3101 return -EINVAL; 3102 } 3103 3104 return smk_curacc_sem(isp, may); 3105 } 3106 3107 /** 3108 * smack_sem_semop - Smack checks of semaphore operations 3109 * @isp: the object 3110 * @sops: unused 3111 * @nsops: unused 3112 * @alter: unused 3113 * 3114 * Treated as read and write in all cases. 3115 * 3116 * Returns 0 if access is allowed, error code otherwise 3117 */ 3118 static int smack_sem_semop(struct kern_ipc_perm *isp, struct sembuf *sops, 3119 unsigned nsops, int alter) 3120 { 3121 return smk_curacc_sem(isp, MAY_READWRITE); 3122 } 3123 3124 /** 3125 * smk_curacc_msq : helper to check if current has access on msq 3126 * @isp : the msq 3127 * @access : access requested 3128 * 3129 * return 0 if current has access, error otherwise 3130 */ 3131 static int smk_curacc_msq(struct kern_ipc_perm *isp, int access) 3132 { 3133 struct smack_known *msp = smack_of_ipc(isp); 3134 struct smk_audit_info ad; 3135 int rc; 3136 3137 #ifdef CONFIG_AUDIT 3138 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); 3139 ad.a.u.ipc_id = isp->id; 3140 #endif 3141 rc = smk_curacc(msp, access, &ad); 3142 rc = smk_bu_current("msq", msp, access, rc); 3143 return rc; 3144 } 3145 3146 /** 3147 * smack_msg_queue_associate - Smack access check for msg_queue 3148 * @isp: the object 3149 * @msqflg: access requested 3150 * 3151 * Returns 0 if current has the requested access, error code otherwise 3152 */ 3153 static int smack_msg_queue_associate(struct kern_ipc_perm *isp, int msqflg) 3154 { 3155 int may; 3156 3157 may = smack_flags_to_may(msqflg); 3158 return smk_curacc_msq(isp, may); 3159 } 3160 3161 /** 3162 * smack_msg_queue_msgctl - Smack access check for msg_queue 3163 * @isp: the object 3164 * @cmd: what it wants to do 3165 * 3166 * Returns 0 if current has the requested access, error code otherwise 3167 */ 3168 static int smack_msg_queue_msgctl(struct kern_ipc_perm *isp, int cmd) 3169 { 3170 int may; 3171 3172 switch (cmd) { 3173 case IPC_STAT: 3174 case MSG_STAT: 3175 case MSG_STAT_ANY: 3176 may = MAY_READ; 3177 break; 3178 case IPC_SET: 3179 case IPC_RMID: 3180 may = MAY_READWRITE; 3181 break; 3182 case IPC_INFO: 3183 case MSG_INFO: 3184 /* 3185 * System level information 3186 */ 3187 return 0; 3188 default: 3189 return -EINVAL; 3190 } 3191 3192 return smk_curacc_msq(isp, may); 3193 } 3194 3195 /** 3196 * smack_msg_queue_msgsnd - Smack access check for msg_queue 3197 * @isp: the object 3198 * @msg: unused 3199 * @msqflg: access requested 3200 * 3201 * Returns 0 if current has the requested access, error code otherwise 3202 */ 3203 static int smack_msg_queue_msgsnd(struct kern_ipc_perm *isp, struct msg_msg *msg, 3204 int msqflg) 3205 { 3206 int may; 3207 3208 may = smack_flags_to_may(msqflg); 3209 return smk_curacc_msq(isp, may); 3210 } 3211 3212 /** 3213 * smack_msg_queue_msgrcv - Smack access check for msg_queue 3214 * @isp: the object 3215 * @msg: unused 3216 * @target: unused 3217 * @type: unused 3218 * @mode: unused 3219 * 3220 * Returns 0 if current has read and write access, error code otherwise 3221 */ 3222 static int smack_msg_queue_msgrcv(struct kern_ipc_perm *isp, 3223 struct msg_msg *msg, 3224 struct task_struct *target, long type, 3225 int mode) 3226 { 3227 return smk_curacc_msq(isp, MAY_READWRITE); 3228 } 3229 3230 /** 3231 * smack_ipc_permission - Smack access for ipc_permission() 3232 * @ipp: the object permissions 3233 * @flag: access requested 3234 * 3235 * Returns 0 if current has read and write access, error code otherwise 3236 */ 3237 static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) 3238 { 3239 struct smack_known **blob = smack_ipc(ipp); 3240 struct smack_known *iskp = *blob; 3241 int may = smack_flags_to_may(flag); 3242 struct smk_audit_info ad; 3243 int rc; 3244 3245 #ifdef CONFIG_AUDIT 3246 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); 3247 ad.a.u.ipc_id = ipp->id; 3248 #endif 3249 rc = smk_curacc(iskp, may, &ad); 3250 rc = smk_bu_current("svipc", iskp, may, rc); 3251 return rc; 3252 } 3253 3254 /** 3255 * smack_ipc_getsecid - Extract smack security id 3256 * @ipp: the object permissions 3257 * @secid: where result will be saved 3258 */ 3259 static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) 3260 { 3261 struct smack_known **blob = smack_ipc(ipp); 3262 struct smack_known *iskp = *blob; 3263 3264 *secid = iskp->smk_secid; 3265 } 3266 3267 /** 3268 * smack_d_instantiate - Make sure the blob is correct on an inode 3269 * @opt_dentry: dentry where inode will be attached 3270 * @inode: the object 3271 * 3272 * Set the inode's security blob if it hasn't been done already. 3273 */ 3274 static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) 3275 { 3276 struct super_block *sbp; 3277 struct superblock_smack *sbsp; 3278 struct inode_smack *isp; 3279 struct smack_known *skp; 3280 struct smack_known *ckp = smk_of_current(); 3281 struct smack_known *final; 3282 char trattr[TRANS_TRUE_SIZE]; 3283 int transflag = 0; 3284 int rc; 3285 struct dentry *dp; 3286 3287 if (inode == NULL) 3288 return; 3289 3290 isp = smack_inode(inode); 3291 3292 /* 3293 * If the inode is already instantiated 3294 * take the quick way out 3295 */ 3296 if (isp->smk_flags & SMK_INODE_INSTANT) 3297 return; 3298 3299 sbp = inode->i_sb; 3300 sbsp = smack_superblock(sbp); 3301 /* 3302 * We're going to use the superblock default label 3303 * if there's no label on the file. 3304 */ 3305 final = sbsp->smk_default; 3306 3307 /* 3308 * If this is the root inode the superblock 3309 * may be in the process of initialization. 3310 * If that is the case use the root value out 3311 * of the superblock. 3312 */ 3313 if (opt_dentry->d_parent == opt_dentry) { 3314 switch (sbp->s_magic) { 3315 case CGROUP_SUPER_MAGIC: 3316 case CGROUP2_SUPER_MAGIC: 3317 /* 3318 * The cgroup filesystem is never mounted, 3319 * so there's no opportunity to set the mount 3320 * options. 3321 */ 3322 sbsp->smk_root = &smack_known_star; 3323 sbsp->smk_default = &smack_known_star; 3324 isp->smk_inode = sbsp->smk_root; 3325 break; 3326 case TMPFS_MAGIC: 3327 /* 3328 * What about shmem/tmpfs anonymous files with dentry 3329 * obtained from d_alloc_pseudo()? 3330 */ 3331 isp->smk_inode = smk_of_current(); 3332 break; 3333 case PIPEFS_MAGIC: 3334 isp->smk_inode = smk_of_current(); 3335 break; 3336 case SOCKFS_MAGIC: 3337 /* 3338 * Socket access is controlled by the socket 3339 * structures associated with the task involved. 3340 */ 3341 isp->smk_inode = &smack_known_star; 3342 break; 3343 default: 3344 isp->smk_inode = sbsp->smk_root; 3345 break; 3346 } 3347 isp->smk_flags |= SMK_INODE_INSTANT; 3348 return; 3349 } 3350 3351 /* 3352 * This is pretty hackish. 3353 * Casey says that we shouldn't have to do 3354 * file system specific code, but it does help 3355 * with keeping it simple. 3356 */ 3357 switch (sbp->s_magic) { 3358 case SMACK_MAGIC: 3359 case CGROUP_SUPER_MAGIC: 3360 case CGROUP2_SUPER_MAGIC: 3361 /* 3362 * Casey says that it's a little embarrassing 3363 * that the smack file system doesn't do 3364 * extended attributes. 3365 * 3366 * Cgroupfs is special 3367 */ 3368 final = &smack_known_star; 3369 break; 3370 case DEVPTS_SUPER_MAGIC: 3371 /* 3372 * devpts seems content with the label of the task. 3373 * Programs that change smack have to treat the 3374 * pty with respect. 3375 */ 3376 final = ckp; 3377 break; 3378 case PROC_SUPER_MAGIC: 3379 /* 3380 * Casey says procfs appears not to care. 3381 * The superblock default suffices. 3382 */ 3383 break; 3384 case TMPFS_MAGIC: 3385 /* 3386 * Device labels should come from the filesystem, 3387 * but watch out, because they're volitile, 3388 * getting recreated on every reboot. 3389 */ 3390 final = &smack_known_star; 3391 /* 3392 * If a smack value has been set we want to use it, 3393 * but since tmpfs isn't giving us the opportunity 3394 * to set mount options simulate setting the 3395 * superblock default. 3396 */ 3397 fallthrough; 3398 default: 3399 /* 3400 * This isn't an understood special case. 3401 * Get the value from the xattr. 3402 */ 3403 3404 /* 3405 * UNIX domain sockets use lower level socket data. 3406 */ 3407 if (S_ISSOCK(inode->i_mode)) { 3408 final = &smack_known_star; 3409 break; 3410 } 3411 /* 3412 * No xattr support means, alas, no SMACK label. 3413 * Use the aforeapplied default. 3414 * It would be curious if the label of the task 3415 * does not match that assigned. 3416 */ 3417 if (!(inode->i_opflags & IOP_XATTR)) 3418 break; 3419 /* 3420 * Get the dentry for xattr. 3421 */ 3422 dp = dget(opt_dentry); 3423 skp = smk_fetch(XATTR_NAME_SMACK, inode, dp); 3424 if (!IS_ERR_OR_NULL(skp)) 3425 final = skp; 3426 3427 /* 3428 * Transmuting directory 3429 */ 3430 if (S_ISDIR(inode->i_mode)) { 3431 /* 3432 * If this is a new directory and the label was 3433 * transmuted when the inode was initialized 3434 * set the transmute attribute on the directory 3435 * and mark the inode. 3436 * 3437 * If there is a transmute attribute on the 3438 * directory mark the inode. 3439 */ 3440 if (isp->smk_flags & SMK_INODE_CHANGED) { 3441 isp->smk_flags &= ~SMK_INODE_CHANGED; 3442 rc = __vfs_setxattr(&init_user_ns, dp, inode, 3443 XATTR_NAME_SMACKTRANSMUTE, 3444 TRANS_TRUE, TRANS_TRUE_SIZE, 3445 0); 3446 } else { 3447 rc = __vfs_getxattr(dp, inode, 3448 XATTR_NAME_SMACKTRANSMUTE, trattr, 3449 TRANS_TRUE_SIZE); 3450 if (rc >= 0 && strncmp(trattr, TRANS_TRUE, 3451 TRANS_TRUE_SIZE) != 0) 3452 rc = -EINVAL; 3453 } 3454 if (rc >= 0) 3455 transflag = SMK_INODE_TRANSMUTE; 3456 } 3457 /* 3458 * Don't let the exec or mmap label be "*" or "@". 3459 */ 3460 skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); 3461 if (IS_ERR(skp) || skp == &smack_known_star || 3462 skp == &smack_known_web) 3463 skp = NULL; 3464 isp->smk_task = skp; 3465 3466 skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); 3467 if (IS_ERR(skp) || skp == &smack_known_star || 3468 skp == &smack_known_web) 3469 skp = NULL; 3470 isp->smk_mmap = skp; 3471 3472 dput(dp); 3473 break; 3474 } 3475 3476 if (final == NULL) 3477 isp->smk_inode = ckp; 3478 else 3479 isp->smk_inode = final; 3480 3481 isp->smk_flags |= (SMK_INODE_INSTANT | transflag); 3482 3483 return; 3484 } 3485 3486 /** 3487 * smack_getprocattr - Smack process attribute access 3488 * @p: the object task 3489 * @name: the name of the attribute in /proc/.../attr 3490 * @value: where to put the result 3491 * 3492 * Places a copy of the task Smack into value 3493 * 3494 * Returns the length of the smack label or an error code 3495 */ 3496 static int smack_getprocattr(struct task_struct *p, const char *name, char **value) 3497 { 3498 struct smack_known *skp = smk_of_task_struct_obj(p); 3499 char *cp; 3500 int slen; 3501 3502 if (strcmp(name, "current") != 0) 3503 return -EINVAL; 3504 3505 cp = kstrdup(skp->smk_known, GFP_KERNEL); 3506 if (cp == NULL) 3507 return -ENOMEM; 3508 3509 slen = strlen(cp); 3510 *value = cp; 3511 return slen; 3512 } 3513 3514 /** 3515 * smack_setprocattr - Smack process attribute setting 3516 * @name: the name of the attribute in /proc/.../attr 3517 * @value: the value to set 3518 * @size: the size of the value 3519 * 3520 * Sets the Smack value of the task. Only setting self 3521 * is permitted and only with privilege 3522 * 3523 * Returns the length of the smack label or an error code 3524 */ 3525 static int smack_setprocattr(const char *name, void *value, size_t size) 3526 { 3527 struct task_smack *tsp = smack_cred(current_cred()); 3528 struct cred *new; 3529 struct smack_known *skp; 3530 struct smack_known_list_elem *sklep; 3531 int rc; 3532 3533 if (!smack_privileged(CAP_MAC_ADMIN) && list_empty(&tsp->smk_relabel)) 3534 return -EPERM; 3535 3536 if (value == NULL || size == 0 || size >= SMK_LONGLABEL) 3537 return -EINVAL; 3538 3539 if (strcmp(name, "current") != 0) 3540 return -EINVAL; 3541 3542 skp = smk_import_entry(value, size); 3543 if (IS_ERR(skp)) 3544 return PTR_ERR(skp); 3545 3546 /* 3547 * No process is ever allowed the web ("@") label 3548 * and the star ("*") label. 3549 */ 3550 if (skp == &smack_known_web || skp == &smack_known_star) 3551 return -EINVAL; 3552 3553 if (!smack_privileged(CAP_MAC_ADMIN)) { 3554 rc = -EPERM; 3555 list_for_each_entry(sklep, &tsp->smk_relabel, list) 3556 if (sklep->smk_label == skp) { 3557 rc = 0; 3558 break; 3559 } 3560 if (rc) 3561 return rc; 3562 } 3563 3564 new = prepare_creds(); 3565 if (new == NULL) 3566 return -ENOMEM; 3567 3568 tsp = smack_cred(new); 3569 tsp->smk_task = skp; 3570 /* 3571 * process can change its label only once 3572 */ 3573 smk_destroy_label_list(&tsp->smk_relabel); 3574 3575 commit_creds(new); 3576 return size; 3577 } 3578 3579 /** 3580 * smack_unix_stream_connect - Smack access on UDS 3581 * @sock: one sock 3582 * @other: the other sock 3583 * @newsk: unused 3584 * 3585 * Return 0 if a subject with the smack of sock could access 3586 * an object with the smack of other, otherwise an error code 3587 */ 3588 static int smack_unix_stream_connect(struct sock *sock, 3589 struct sock *other, struct sock *newsk) 3590 { 3591 struct smack_known *skp; 3592 struct smack_known *okp; 3593 struct socket_smack *ssp = sock->sk_security; 3594 struct socket_smack *osp = other->sk_security; 3595 struct socket_smack *nsp = newsk->sk_security; 3596 struct smk_audit_info ad; 3597 int rc = 0; 3598 #ifdef CONFIG_AUDIT 3599 struct lsm_network_audit net; 3600 #endif 3601 3602 if (!smack_privileged(CAP_MAC_OVERRIDE)) { 3603 skp = ssp->smk_out; 3604 okp = osp->smk_in; 3605 #ifdef CONFIG_AUDIT 3606 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 3607 smk_ad_setfield_u_net_sk(&ad, other); 3608 #endif 3609 rc = smk_access(skp, okp, MAY_WRITE, &ad); 3610 rc = smk_bu_note("UDS connect", skp, okp, MAY_WRITE, rc); 3611 if (rc == 0) { 3612 okp = osp->smk_out; 3613 skp = ssp->smk_in; 3614 rc = smk_access(okp, skp, MAY_WRITE, &ad); 3615 rc = smk_bu_note("UDS connect", okp, skp, 3616 MAY_WRITE, rc); 3617 } 3618 } 3619 3620 /* 3621 * Cross reference the peer labels for SO_PEERSEC. 3622 */ 3623 if (rc == 0) { 3624 nsp->smk_packet = ssp->smk_out; 3625 ssp->smk_packet = osp->smk_out; 3626 } 3627 3628 return rc; 3629 } 3630 3631 /** 3632 * smack_unix_may_send - Smack access on UDS 3633 * @sock: one socket 3634 * @other: the other socket 3635 * 3636 * Return 0 if a subject with the smack of sock could access 3637 * an object with the smack of other, otherwise an error code 3638 */ 3639 static int smack_unix_may_send(struct socket *sock, struct socket *other) 3640 { 3641 struct socket_smack *ssp = sock->sk->sk_security; 3642 struct socket_smack *osp = other->sk->sk_security; 3643 struct smk_audit_info ad; 3644 int rc; 3645 3646 #ifdef CONFIG_AUDIT 3647 struct lsm_network_audit net; 3648 3649 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 3650 smk_ad_setfield_u_net_sk(&ad, other->sk); 3651 #endif 3652 3653 if (smack_privileged(CAP_MAC_OVERRIDE)) 3654 return 0; 3655 3656 rc = smk_access(ssp->smk_out, osp->smk_in, MAY_WRITE, &ad); 3657 rc = smk_bu_note("UDS send", ssp->smk_out, osp->smk_in, MAY_WRITE, rc); 3658 return rc; 3659 } 3660 3661 /** 3662 * smack_socket_sendmsg - Smack check based on destination host 3663 * @sock: the socket 3664 * @msg: the message 3665 * @size: the size of the message 3666 * 3667 * Return 0 if the current subject can write to the destination host. 3668 * For IPv4 this is only a question if the destination is a single label host. 3669 * For IPv6 this is a check against the label of the port. 3670 */ 3671 static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, 3672 int size) 3673 { 3674 struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; 3675 #if IS_ENABLED(CONFIG_IPV6) 3676 struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name; 3677 #endif 3678 #ifdef SMACK_IPV6_SECMARK_LABELING 3679 struct socket_smack *ssp = sock->sk->sk_security; 3680 struct smack_known *rsp; 3681 #endif 3682 int rc = 0; 3683 3684 /* 3685 * Perfectly reasonable for this to be NULL 3686 */ 3687 if (sip == NULL) 3688 return 0; 3689 3690 switch (sock->sk->sk_family) { 3691 case AF_INET: 3692 if (msg->msg_namelen < sizeof(struct sockaddr_in) || 3693 sip->sin_family != AF_INET) 3694 return -EINVAL; 3695 rc = smk_ipv4_check(sock->sk, sip); 3696 break; 3697 #if IS_ENABLED(CONFIG_IPV6) 3698 case AF_INET6: 3699 if (msg->msg_namelen < SIN6_LEN_RFC2133 || 3700 sap->sin6_family != AF_INET6) 3701 return -EINVAL; 3702 #ifdef SMACK_IPV6_SECMARK_LABELING 3703 rsp = smack_ipv6host_label(sap); 3704 if (rsp != NULL) 3705 rc = smk_ipv6_check(ssp->smk_out, rsp, sap, 3706 SMK_CONNECTING); 3707 #endif 3708 #ifdef SMACK_IPV6_PORT_LABELING 3709 rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING); 3710 #endif 3711 #endif /* IS_ENABLED(CONFIG_IPV6) */ 3712 break; 3713 } 3714 return rc; 3715 } 3716 3717 /** 3718 * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack 3719 * @sap: netlabel secattr 3720 * @ssp: socket security information 3721 * 3722 * Returns a pointer to a Smack label entry found on the label list. 3723 */ 3724 static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap, 3725 struct socket_smack *ssp) 3726 { 3727 struct smack_known *skp; 3728 int found = 0; 3729 int acat; 3730 int kcat; 3731 3732 /* 3733 * Netlabel found it in the cache. 3734 */ 3735 if ((sap->flags & NETLBL_SECATTR_CACHE) != 0) 3736 return (struct smack_known *)sap->cache->data; 3737 3738 if ((sap->flags & NETLBL_SECATTR_SECID) != 0) 3739 /* 3740 * Looks like a fallback, which gives us a secid. 3741 */ 3742 return smack_from_secid(sap->attr.secid); 3743 3744 if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { 3745 /* 3746 * Looks like a CIPSO packet. 3747 * If there are flags but no level netlabel isn't 3748 * behaving the way we expect it to. 3749 * 3750 * Look it up in the label table 3751 * Without guidance regarding the smack value 3752 * for the packet fall back on the network 3753 * ambient value. 3754 */ 3755 rcu_read_lock(); 3756 list_for_each_entry_rcu(skp, &smack_known_list, list) { 3757 if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl) 3758 continue; 3759 /* 3760 * Compare the catsets. Use the netlbl APIs. 3761 */ 3762 if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) { 3763 if ((skp->smk_netlabel.flags & 3764 NETLBL_SECATTR_MLS_CAT) == 0) 3765 found = 1; 3766 break; 3767 } 3768 for (acat = -1, kcat = -1; acat == kcat; ) { 3769 acat = netlbl_catmap_walk(sap->attr.mls.cat, 3770 acat + 1); 3771 kcat = netlbl_catmap_walk( 3772 skp->smk_netlabel.attr.mls.cat, 3773 kcat + 1); 3774 if (acat < 0 || kcat < 0) 3775 break; 3776 } 3777 if (acat == kcat) { 3778 found = 1; 3779 break; 3780 } 3781 } 3782 rcu_read_unlock(); 3783 3784 if (found) 3785 return skp; 3786 3787 if (ssp != NULL && ssp->smk_in == &smack_known_star) 3788 return &smack_known_web; 3789 return &smack_known_star; 3790 } 3791 /* 3792 * Without guidance regarding the smack value 3793 * for the packet fall back on the network 3794 * ambient value. 3795 */ 3796 return smack_net_ambient; 3797 } 3798 3799 #if IS_ENABLED(CONFIG_IPV6) 3800 static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip) 3801 { 3802 u8 nexthdr; 3803 int offset; 3804 int proto = -EINVAL; 3805 struct ipv6hdr _ipv6h; 3806 struct ipv6hdr *ip6; 3807 __be16 frag_off; 3808 struct tcphdr _tcph, *th; 3809 struct udphdr _udph, *uh; 3810 struct dccp_hdr _dccph, *dh; 3811 3812 sip->sin6_port = 0; 3813 3814 offset = skb_network_offset(skb); 3815 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); 3816 if (ip6 == NULL) 3817 return -EINVAL; 3818 sip->sin6_addr = ip6->saddr; 3819 3820 nexthdr = ip6->nexthdr; 3821 offset += sizeof(_ipv6h); 3822 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); 3823 if (offset < 0) 3824 return -EINVAL; 3825 3826 proto = nexthdr; 3827 switch (proto) { 3828 case IPPROTO_TCP: 3829 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); 3830 if (th != NULL) 3831 sip->sin6_port = th->source; 3832 break; 3833 case IPPROTO_UDP: 3834 case IPPROTO_UDPLITE: 3835 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); 3836 if (uh != NULL) 3837 sip->sin6_port = uh->source; 3838 break; 3839 case IPPROTO_DCCP: 3840 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); 3841 if (dh != NULL) 3842 sip->sin6_port = dh->dccph_sport; 3843 break; 3844 } 3845 return proto; 3846 } 3847 #endif /* CONFIG_IPV6 */ 3848 3849 /** 3850 * smack_from_skb - Smack data from the secmark in an skb 3851 * @skb: packet 3852 * 3853 * Returns smack_known of the secmark or NULL if that won't work. 3854 */ 3855 #ifdef CONFIG_NETWORK_SECMARK 3856 static struct smack_known *smack_from_skb(struct sk_buff *skb) 3857 { 3858 if (skb == NULL || skb->secmark == 0) 3859 return NULL; 3860 3861 return smack_from_secid(skb->secmark); 3862 } 3863 #else 3864 static inline struct smack_known *smack_from_skb(struct sk_buff *skb) 3865 { 3866 return NULL; 3867 } 3868 #endif 3869 3870 /** 3871 * smack_from_netlbl - Smack data from the IP options in an skb 3872 * @sk: socket data came in on 3873 * @family: address family 3874 * @skb: packet 3875 * 3876 * Find the Smack label in the IP options. If it hasn't been 3877 * added to the netlabel cache, add it here. 3878 * 3879 * Returns smack_known of the IP options or NULL if that won't work. 3880 */ 3881 static struct smack_known *smack_from_netlbl(const struct sock *sk, u16 family, 3882 struct sk_buff *skb) 3883 { 3884 struct netlbl_lsm_secattr secattr; 3885 struct socket_smack *ssp = NULL; 3886 struct smack_known *skp = NULL; 3887 3888 netlbl_secattr_init(&secattr); 3889 3890 if (sk) 3891 ssp = sk->sk_security; 3892 3893 if (netlbl_skbuff_getattr(skb, family, &secattr) == 0) { 3894 skp = smack_from_secattr(&secattr, ssp); 3895 if (secattr.flags & NETLBL_SECATTR_CACHEABLE) 3896 netlbl_cache_add(skb, family, &skp->smk_netlabel); 3897 } 3898 3899 netlbl_secattr_destroy(&secattr); 3900 3901 return skp; 3902 } 3903 3904 /** 3905 * smack_socket_sock_rcv_skb - Smack packet delivery access check 3906 * @sk: socket 3907 * @skb: packet 3908 * 3909 * Returns 0 if the packet should be delivered, an error code otherwise 3910 */ 3911 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) 3912 { 3913 struct socket_smack *ssp = sk->sk_security; 3914 struct smack_known *skp = NULL; 3915 int rc = 0; 3916 struct smk_audit_info ad; 3917 u16 family = sk->sk_family; 3918 #ifdef CONFIG_AUDIT 3919 struct lsm_network_audit net; 3920 #endif 3921 #if IS_ENABLED(CONFIG_IPV6) 3922 struct sockaddr_in6 sadd; 3923 int proto; 3924 3925 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP)) 3926 family = PF_INET; 3927 #endif /* CONFIG_IPV6 */ 3928 3929 switch (family) { 3930 case PF_INET: 3931 /* 3932 * If there is a secmark use it rather than the CIPSO label. 3933 * If there is no secmark fall back to CIPSO. 3934 * The secmark is assumed to reflect policy better. 3935 */ 3936 skp = smack_from_skb(skb); 3937 if (skp == NULL) { 3938 skp = smack_from_netlbl(sk, family, skb); 3939 if (skp == NULL) 3940 skp = smack_net_ambient; 3941 } 3942 3943 #ifdef CONFIG_AUDIT 3944 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 3945 ad.a.u.net->family = family; 3946 ad.a.u.net->netif = skb->skb_iif; 3947 ipv4_skb_to_auditdata(skb, &ad.a, NULL); 3948 #endif 3949 /* 3950 * Receiving a packet requires that the other end 3951 * be able to write here. Read access is not required. 3952 * This is the simplist possible security model 3953 * for networking. 3954 */ 3955 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad); 3956 rc = smk_bu_note("IPv4 delivery", skp, ssp->smk_in, 3957 MAY_WRITE, rc); 3958 if (rc != 0) 3959 netlbl_skbuff_err(skb, family, rc, 0); 3960 break; 3961 #if IS_ENABLED(CONFIG_IPV6) 3962 case PF_INET6: 3963 proto = smk_skb_to_addr_ipv6(skb, &sadd); 3964 if (proto != IPPROTO_UDP && proto != IPPROTO_UDPLITE && 3965 proto != IPPROTO_TCP && proto != IPPROTO_DCCP) 3966 break; 3967 #ifdef SMACK_IPV6_SECMARK_LABELING 3968 skp = smack_from_skb(skb); 3969 if (skp == NULL) { 3970 if (smk_ipv6_localhost(&sadd)) 3971 break; 3972 skp = smack_ipv6host_label(&sadd); 3973 if (skp == NULL) 3974 skp = smack_net_ambient; 3975 } 3976 #ifdef CONFIG_AUDIT 3977 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 3978 ad.a.u.net->family = family; 3979 ad.a.u.net->netif = skb->skb_iif; 3980 ipv6_skb_to_auditdata(skb, &ad.a, NULL); 3981 #endif /* CONFIG_AUDIT */ 3982 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad); 3983 rc = smk_bu_note("IPv6 delivery", skp, ssp->smk_in, 3984 MAY_WRITE, rc); 3985 #endif /* SMACK_IPV6_SECMARK_LABELING */ 3986 #ifdef SMACK_IPV6_PORT_LABELING 3987 rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING); 3988 #endif /* SMACK_IPV6_PORT_LABELING */ 3989 if (rc != 0) 3990 icmpv6_send(skb, ICMPV6_DEST_UNREACH, 3991 ICMPV6_ADM_PROHIBITED, 0); 3992 break; 3993 #endif /* CONFIG_IPV6 */ 3994 } 3995 3996 return rc; 3997 } 3998 3999 /** 4000 * smack_socket_getpeersec_stream - pull in packet label 4001 * @sock: the socket 4002 * @optval: user's destination 4003 * @optlen: size thereof 4004 * @len: max thereof 4005 * 4006 * returns zero on success, an error code otherwise 4007 */ 4008 static int smack_socket_getpeersec_stream(struct socket *sock, 4009 char __user *optval, 4010 int __user *optlen, unsigned len) 4011 { 4012 struct socket_smack *ssp; 4013 char *rcp = ""; 4014 int slen = 1; 4015 int rc = 0; 4016 4017 ssp = sock->sk->sk_security; 4018 if (ssp->smk_packet != NULL) { 4019 rcp = ssp->smk_packet->smk_known; 4020 slen = strlen(rcp) + 1; 4021 } 4022 4023 if (slen > len) 4024 rc = -ERANGE; 4025 else if (copy_to_user(optval, rcp, slen) != 0) 4026 rc = -EFAULT; 4027 4028 if (put_user(slen, optlen) != 0) 4029 rc = -EFAULT; 4030 4031 return rc; 4032 } 4033 4034 4035 /** 4036 * smack_socket_getpeersec_dgram - pull in packet label 4037 * @sock: the peer socket 4038 * @skb: packet data 4039 * @secid: pointer to where to put the secid of the packet 4040 * 4041 * Sets the netlabel socket state on sk from parent 4042 */ 4043 static int smack_socket_getpeersec_dgram(struct socket *sock, 4044 struct sk_buff *skb, u32 *secid) 4045 4046 { 4047 struct socket_smack *ssp = NULL; 4048 struct smack_known *skp; 4049 struct sock *sk = NULL; 4050 int family = PF_UNSPEC; 4051 u32 s = 0; /* 0 is the invalid secid */ 4052 4053 if (skb != NULL) { 4054 if (skb->protocol == htons(ETH_P_IP)) 4055 family = PF_INET; 4056 #if IS_ENABLED(CONFIG_IPV6) 4057 else if (skb->protocol == htons(ETH_P_IPV6)) 4058 family = PF_INET6; 4059 #endif /* CONFIG_IPV6 */ 4060 } 4061 if (family == PF_UNSPEC && sock != NULL) 4062 family = sock->sk->sk_family; 4063 4064 switch (family) { 4065 case PF_UNIX: 4066 ssp = sock->sk->sk_security; 4067 s = ssp->smk_out->smk_secid; 4068 break; 4069 case PF_INET: 4070 skp = smack_from_skb(skb); 4071 if (skp) { 4072 s = skp->smk_secid; 4073 break; 4074 } 4075 /* 4076 * Translate what netlabel gave us. 4077 */ 4078 if (sock != NULL) 4079 sk = sock->sk; 4080 skp = smack_from_netlbl(sk, family, skb); 4081 if (skp != NULL) 4082 s = skp->smk_secid; 4083 break; 4084 case PF_INET6: 4085 #ifdef SMACK_IPV6_SECMARK_LABELING 4086 skp = smack_from_skb(skb); 4087 if (skp) 4088 s = skp->smk_secid; 4089 #endif 4090 break; 4091 } 4092 *secid = s; 4093 if (s == 0) 4094 return -EINVAL; 4095 return 0; 4096 } 4097 4098 /** 4099 * smack_sock_graft - Initialize a newly created socket with an existing sock 4100 * @sk: child sock 4101 * @parent: parent socket 4102 * 4103 * Set the smk_{in,out} state of an existing sock based on the process that 4104 * is creating the new socket. 4105 */ 4106 static void smack_sock_graft(struct sock *sk, struct socket *parent) 4107 { 4108 struct socket_smack *ssp; 4109 struct smack_known *skp = smk_of_current(); 4110 4111 if (sk == NULL || 4112 (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)) 4113 return; 4114 4115 ssp = sk->sk_security; 4116 ssp->smk_in = skp; 4117 ssp->smk_out = skp; 4118 /* cssp->smk_packet is already set in smack_inet_csk_clone() */ 4119 } 4120 4121 /** 4122 * smack_inet_conn_request - Smack access check on connect 4123 * @sk: socket involved 4124 * @skb: packet 4125 * @req: unused 4126 * 4127 * Returns 0 if a task with the packet label could write to 4128 * the socket, otherwise an error code 4129 */ 4130 static int smack_inet_conn_request(const struct sock *sk, struct sk_buff *skb, 4131 struct request_sock *req) 4132 { 4133 u16 family = sk->sk_family; 4134 struct smack_known *skp; 4135 struct socket_smack *ssp = sk->sk_security; 4136 struct sockaddr_in addr; 4137 struct iphdr *hdr; 4138 struct smack_known *hskp; 4139 int rc; 4140 struct smk_audit_info ad; 4141 #ifdef CONFIG_AUDIT 4142 struct lsm_network_audit net; 4143 #endif 4144 4145 #if IS_ENABLED(CONFIG_IPV6) 4146 if (family == PF_INET6) { 4147 /* 4148 * Handle mapped IPv4 packets arriving 4149 * via IPv6 sockets. Don't set up netlabel 4150 * processing on IPv6. 4151 */ 4152 if (skb->protocol == htons(ETH_P_IP)) 4153 family = PF_INET; 4154 else 4155 return 0; 4156 } 4157 #endif /* CONFIG_IPV6 */ 4158 4159 /* 4160 * If there is a secmark use it rather than the CIPSO label. 4161 * If there is no secmark fall back to CIPSO. 4162 * The secmark is assumed to reflect policy better. 4163 */ 4164 skp = smack_from_skb(skb); 4165 if (skp == NULL) { 4166 skp = smack_from_netlbl(sk, family, skb); 4167 if (skp == NULL) 4168 skp = &smack_known_huh; 4169 } 4170 4171 #ifdef CONFIG_AUDIT 4172 smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); 4173 ad.a.u.net->family = family; 4174 ad.a.u.net->netif = skb->skb_iif; 4175 ipv4_skb_to_auditdata(skb, &ad.a, NULL); 4176 #endif 4177 /* 4178 * Receiving a packet requires that the other end be able to write 4179 * here. Read access is not required. 4180 */ 4181 rc = smk_access(skp, ssp->smk_in, MAY_WRITE, &ad); 4182 rc = smk_bu_note("IPv4 connect", skp, ssp->smk_in, MAY_WRITE, rc); 4183 if (rc != 0) 4184 return rc; 4185 4186 /* 4187 * Save the peer's label in the request_sock so we can later setup 4188 * smk_packet in the child socket so that SO_PEERCRED can report it. 4189 */ 4190 req->peer_secid = skp->smk_secid; 4191 4192 /* 4193 * We need to decide if we want to label the incoming connection here 4194 * if we do we only need to label the request_sock and the stack will 4195 * propagate the wire-label to the sock when it is created. 4196 */ 4197 hdr = ip_hdr(skb); 4198 addr.sin_addr.s_addr = hdr->saddr; 4199 rcu_read_lock(); 4200 hskp = smack_ipv4host_label(&addr); 4201 rcu_read_unlock(); 4202 4203 if (hskp == NULL) 4204 rc = netlbl_req_setattr(req, &skp->smk_netlabel); 4205 else 4206 netlbl_req_delattr(req); 4207 4208 return rc; 4209 } 4210 4211 /** 4212 * smack_inet_csk_clone - Copy the connection information to the new socket 4213 * @sk: the new socket 4214 * @req: the connection's request_sock 4215 * 4216 * Transfer the connection's peer label to the newly created socket. 4217 */ 4218 static void smack_inet_csk_clone(struct sock *sk, 4219 const struct request_sock *req) 4220 { 4221 struct socket_smack *ssp = sk->sk_security; 4222 struct smack_known *skp; 4223 4224 if (req->peer_secid != 0) { 4225 skp = smack_from_secid(req->peer_secid); 4226 ssp->smk_packet = skp; 4227 } else 4228 ssp->smk_packet = NULL; 4229 } 4230 4231 /* 4232 * Key management security hooks 4233 * 4234 * Casey has not tested key support very heavily. 4235 * The permission check is most likely too restrictive. 4236 * If you care about keys please have a look. 4237 */ 4238 #ifdef CONFIG_KEYS 4239 4240 /** 4241 * smack_key_alloc - Set the key security blob 4242 * @key: object 4243 * @cred: the credentials to use 4244 * @flags: unused 4245 * 4246 * No allocation required 4247 * 4248 * Returns 0 4249 */ 4250 static int smack_key_alloc(struct key *key, const struct cred *cred, 4251 unsigned long flags) 4252 { 4253 struct smack_known *skp = smk_of_task(smack_cred(cred)); 4254 4255 key->security = skp; 4256 return 0; 4257 } 4258 4259 /** 4260 * smack_key_free - Clear the key security blob 4261 * @key: the object 4262 * 4263 * Clear the blob pointer 4264 */ 4265 static void smack_key_free(struct key *key) 4266 { 4267 key->security = NULL; 4268 } 4269 4270 /** 4271 * smack_key_permission - Smack access on a key 4272 * @key_ref: gets to the object 4273 * @cred: the credentials to use 4274 * @need_perm: requested key permission 4275 * 4276 * Return 0 if the task has read and write to the object, 4277 * an error code otherwise 4278 */ 4279 static int smack_key_permission(key_ref_t key_ref, 4280 const struct cred *cred, 4281 enum key_need_perm need_perm) 4282 { 4283 struct key *keyp; 4284 struct smk_audit_info ad; 4285 struct smack_known *tkp = smk_of_task(smack_cred(cred)); 4286 int request = 0; 4287 int rc; 4288 4289 /* 4290 * Validate requested permissions 4291 */ 4292 switch (need_perm) { 4293 case KEY_NEED_READ: 4294 case KEY_NEED_SEARCH: 4295 case KEY_NEED_VIEW: 4296 request |= MAY_READ; 4297 break; 4298 case KEY_NEED_WRITE: 4299 case KEY_NEED_LINK: 4300 case KEY_NEED_SETATTR: 4301 request |= MAY_WRITE; 4302 break; 4303 case KEY_NEED_UNSPECIFIED: 4304 case KEY_NEED_UNLINK: 4305 case KEY_SYSADMIN_OVERRIDE: 4306 case KEY_AUTHTOKEN_OVERRIDE: 4307 case KEY_DEFER_PERM_CHECK: 4308 return 0; 4309 default: 4310 return -EINVAL; 4311 } 4312 4313 keyp = key_ref_to_ptr(key_ref); 4314 if (keyp == NULL) 4315 return -EINVAL; 4316 /* 4317 * If the key hasn't been initialized give it access so that 4318 * it may do so. 4319 */ 4320 if (keyp->security == NULL) 4321 return 0; 4322 /* 4323 * This should not occur 4324 */ 4325 if (tkp == NULL) 4326 return -EACCES; 4327 4328 if (smack_privileged(CAP_MAC_OVERRIDE)) 4329 return 0; 4330 4331 #ifdef CONFIG_AUDIT 4332 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); 4333 ad.a.u.key_struct.key = keyp->serial; 4334 ad.a.u.key_struct.key_desc = keyp->description; 4335 #endif 4336 rc = smk_access(tkp, keyp->security, request, &ad); 4337 rc = smk_bu_note("key access", tkp, keyp->security, request, rc); 4338 return rc; 4339 } 4340 4341 /* 4342 * smack_key_getsecurity - Smack label tagging the key 4343 * @key points to the key to be queried 4344 * @_buffer points to a pointer that should be set to point to the 4345 * resulting string (if no label or an error occurs). 4346 * Return the length of the string (including terminating NUL) or -ve if 4347 * an error. 4348 * May also return 0 (and a NULL buffer pointer) if there is no label. 4349 */ 4350 static int smack_key_getsecurity(struct key *key, char **_buffer) 4351 { 4352 struct smack_known *skp = key->security; 4353 size_t length; 4354 char *copy; 4355 4356 if (key->security == NULL) { 4357 *_buffer = NULL; 4358 return 0; 4359 } 4360 4361 copy = kstrdup(skp->smk_known, GFP_KERNEL); 4362 if (copy == NULL) 4363 return -ENOMEM; 4364 length = strlen(copy) + 1; 4365 4366 *_buffer = copy; 4367 return length; 4368 } 4369 4370 4371 #ifdef CONFIG_KEY_NOTIFICATIONS 4372 /** 4373 * smack_watch_key - Smack access to watch a key for notifications. 4374 * @key: The key to be watched 4375 * 4376 * Return 0 if the @watch->cred has permission to read from the key object and 4377 * an error otherwise. 4378 */ 4379 static int smack_watch_key(struct key *key) 4380 { 4381 struct smk_audit_info ad; 4382 struct smack_known *tkp = smk_of_current(); 4383 int rc; 4384 4385 if (key == NULL) 4386 return -EINVAL; 4387 /* 4388 * If the key hasn't been initialized give it access so that 4389 * it may do so. 4390 */ 4391 if (key->security == NULL) 4392 return 0; 4393 /* 4394 * This should not occur 4395 */ 4396 if (tkp == NULL) 4397 return -EACCES; 4398 4399 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred())) 4400 return 0; 4401 4402 #ifdef CONFIG_AUDIT 4403 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); 4404 ad.a.u.key_struct.key = key->serial; 4405 ad.a.u.key_struct.key_desc = key->description; 4406 #endif 4407 rc = smk_access(tkp, key->security, MAY_READ, &ad); 4408 rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc); 4409 return rc; 4410 } 4411 #endif /* CONFIG_KEY_NOTIFICATIONS */ 4412 #endif /* CONFIG_KEYS */ 4413 4414 #ifdef CONFIG_WATCH_QUEUE 4415 /** 4416 * smack_post_notification - Smack access to post a notification to a queue 4417 * @w_cred: The credentials of the watcher. 4418 * @cred: The credentials of the event source (may be NULL). 4419 * @n: The notification message to be posted. 4420 */ 4421 static int smack_post_notification(const struct cred *w_cred, 4422 const struct cred *cred, 4423 struct watch_notification *n) 4424 { 4425 struct smk_audit_info ad; 4426 struct smack_known *subj, *obj; 4427 int rc; 4428 4429 /* Always let maintenance notifications through. */ 4430 if (n->type == WATCH_TYPE_META) 4431 return 0; 4432 4433 if (!cred) 4434 return 0; 4435 subj = smk_of_task(smack_cred(cred)); 4436 obj = smk_of_task(smack_cred(w_cred)); 4437 4438 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION); 4439 rc = smk_access(subj, obj, MAY_WRITE, &ad); 4440 rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc); 4441 return rc; 4442 } 4443 #endif /* CONFIG_WATCH_QUEUE */ 4444 4445 /* 4446 * Smack Audit hooks 4447 * 4448 * Audit requires a unique representation of each Smack specific 4449 * rule. This unique representation is used to distinguish the 4450 * object to be audited from remaining kernel objects and also 4451 * works as a glue between the audit hooks. 4452 * 4453 * Since repository entries are added but never deleted, we'll use 4454 * the smack_known label address related to the given audit rule as 4455 * the needed unique representation. This also better fits the smack 4456 * model where nearly everything is a label. 4457 */ 4458 #ifdef CONFIG_AUDIT 4459 4460 /** 4461 * smack_audit_rule_init - Initialize a smack audit rule 4462 * @field: audit rule fields given from user-space (audit.h) 4463 * @op: required testing operator (=, !=, >, <, ...) 4464 * @rulestr: smack label to be audited 4465 * @vrule: pointer to save our own audit rule representation 4466 * 4467 * Prepare to audit cases where (@field @op @rulestr) is true. 4468 * The label to be audited is created if necessay. 4469 */ 4470 static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 4471 { 4472 struct smack_known *skp; 4473 char **rule = (char **)vrule; 4474 *rule = NULL; 4475 4476 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) 4477 return -EINVAL; 4478 4479 if (op != Audit_equal && op != Audit_not_equal) 4480 return -EINVAL; 4481 4482 skp = smk_import_entry(rulestr, 0); 4483 if (IS_ERR(skp)) 4484 return PTR_ERR(skp); 4485 4486 *rule = skp->smk_known; 4487 4488 return 0; 4489 } 4490 4491 /** 4492 * smack_audit_rule_known - Distinguish Smack audit rules 4493 * @krule: rule of interest, in Audit kernel representation format 4494 * 4495 * This is used to filter Smack rules from remaining Audit ones. 4496 * If it's proved that this rule belongs to us, the 4497 * audit_rule_match hook will be called to do the final judgement. 4498 */ 4499 static int smack_audit_rule_known(struct audit_krule *krule) 4500 { 4501 struct audit_field *f; 4502 int i; 4503 4504 for (i = 0; i < krule->field_count; i++) { 4505 f = &krule->fields[i]; 4506 4507 if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER) 4508 return 1; 4509 } 4510 4511 return 0; 4512 } 4513 4514 /** 4515 * smack_audit_rule_match - Audit given object ? 4516 * @secid: security id for identifying the object to test 4517 * @field: audit rule flags given from user-space 4518 * @op: required testing operator 4519 * @vrule: smack internal rule presentation 4520 * 4521 * The core Audit hook. It's used to take the decision of 4522 * whether to audit or not to audit a given object. 4523 */ 4524 static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule) 4525 { 4526 struct smack_known *skp; 4527 char *rule = vrule; 4528 4529 if (unlikely(!rule)) { 4530 WARN_ONCE(1, "Smack: missing rule\n"); 4531 return -ENOENT; 4532 } 4533 4534 if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) 4535 return 0; 4536 4537 skp = smack_from_secid(secid); 4538 4539 /* 4540 * No need to do string comparisons. If a match occurs, 4541 * both pointers will point to the same smack_known 4542 * label. 4543 */ 4544 if (op == Audit_equal) 4545 return (rule == skp->smk_known); 4546 if (op == Audit_not_equal) 4547 return (rule != skp->smk_known); 4548 4549 return 0; 4550 } 4551 4552 /* 4553 * There is no need for a smack_audit_rule_free hook. 4554 * No memory was allocated. 4555 */ 4556 4557 #endif /* CONFIG_AUDIT */ 4558 4559 /** 4560 * smack_ismaclabel - check if xattr @name references a smack MAC label 4561 * @name: Full xattr name to check. 4562 */ 4563 static int smack_ismaclabel(const char *name) 4564 { 4565 return (strcmp(name, XATTR_SMACK_SUFFIX) == 0); 4566 } 4567 4568 4569 /** 4570 * smack_secid_to_secctx - return the smack label for a secid 4571 * @secid: incoming integer 4572 * @secdata: destination 4573 * @seclen: how long it is 4574 * 4575 * Exists for networking code. 4576 */ 4577 static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) 4578 { 4579 struct smack_known *skp = smack_from_secid(secid); 4580 4581 if (secdata) 4582 *secdata = skp->smk_known; 4583 *seclen = strlen(skp->smk_known); 4584 return 0; 4585 } 4586 4587 /** 4588 * smack_secctx_to_secid - return the secid for a smack label 4589 * @secdata: smack label 4590 * @seclen: how long result is 4591 * @secid: outgoing integer 4592 * 4593 * Exists for audit and networking code. 4594 */ 4595 static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) 4596 { 4597 struct smack_known *skp = smk_find_entry(secdata); 4598 4599 if (skp) 4600 *secid = skp->smk_secid; 4601 else 4602 *secid = 0; 4603 return 0; 4604 } 4605 4606 /* 4607 * There used to be a smack_release_secctx hook 4608 * that did nothing back when hooks were in a vector. 4609 * Now that there's a list such a hook adds cost. 4610 */ 4611 4612 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) 4613 { 4614 return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, 4615 ctxlen, 0); 4616 } 4617 4618 static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) 4619 { 4620 return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK, 4621 ctx, ctxlen, 0); 4622 } 4623 4624 static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) 4625 { 4626 struct smack_known *skp = smk_of_inode(inode); 4627 4628 *ctx = skp->smk_known; 4629 *ctxlen = strlen(skp->smk_known); 4630 return 0; 4631 } 4632 4633 static int smack_inode_copy_up(struct dentry *dentry, struct cred **new) 4634 { 4635 4636 struct task_smack *tsp; 4637 struct smack_known *skp; 4638 struct inode_smack *isp; 4639 struct cred *new_creds = *new; 4640 4641 if (new_creds == NULL) { 4642 new_creds = prepare_creds(); 4643 if (new_creds == NULL) 4644 return -ENOMEM; 4645 } 4646 4647 tsp = smack_cred(new_creds); 4648 4649 /* 4650 * Get label from overlay inode and set it in create_sid 4651 */ 4652 isp = smack_inode(d_inode(dentry)); 4653 skp = isp->smk_inode; 4654 tsp->smk_task = skp; 4655 *new = new_creds; 4656 return 0; 4657 } 4658 4659 static int smack_inode_copy_up_xattr(const char *name) 4660 { 4661 /* 4662 * Return 1 if this is the smack access Smack attribute. 4663 */ 4664 if (strcmp(name, XATTR_NAME_SMACK) == 0) 4665 return 1; 4666 4667 return -EOPNOTSUPP; 4668 } 4669 4670 static int smack_dentry_create_files_as(struct dentry *dentry, int mode, 4671 struct qstr *name, 4672 const struct cred *old, 4673 struct cred *new) 4674 { 4675 struct task_smack *otsp = smack_cred(old); 4676 struct task_smack *ntsp = smack_cred(new); 4677 struct inode_smack *isp; 4678 int may; 4679 4680 /* 4681 * Use the process credential unless all of 4682 * the transmuting criteria are met 4683 */ 4684 ntsp->smk_task = otsp->smk_task; 4685 4686 /* 4687 * the attribute of the containing directory 4688 */ 4689 isp = smack_inode(d_inode(dentry->d_parent)); 4690 4691 if (isp->smk_flags & SMK_INODE_TRANSMUTE) { 4692 rcu_read_lock(); 4693 may = smk_access_entry(otsp->smk_task->smk_known, 4694 isp->smk_inode->smk_known, 4695 &otsp->smk_task->smk_rules); 4696 rcu_read_unlock(); 4697 4698 /* 4699 * If the directory is transmuting and the rule 4700 * providing access is transmuting use the containing 4701 * directory label instead of the process label. 4702 */ 4703 if (may > 0 && (may & MAY_TRANSMUTE)) 4704 ntsp->smk_task = isp->smk_inode; 4705 } 4706 return 0; 4707 } 4708 4709 #ifdef CONFIG_IO_URING 4710 /** 4711 * smack_uring_override_creds - Is io_uring cred override allowed? 4712 * @new: the target creds 4713 * 4714 * Check to see if the current task is allowed to override it's credentials 4715 * to service an io_uring operation. 4716 */ 4717 static int smack_uring_override_creds(const struct cred *new) 4718 { 4719 struct task_smack *tsp = smack_cred(current_cred()); 4720 struct task_smack *nsp = smack_cred(new); 4721 4722 /* 4723 * Allow the degenerate case where the new Smack value is 4724 * the same as the current Smack value. 4725 */ 4726 if (tsp->smk_task == nsp->smk_task) 4727 return 0; 4728 4729 if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred())) 4730 return 0; 4731 4732 return -EPERM; 4733 } 4734 4735 /** 4736 * smack_uring_sqpoll - check if a io_uring polling thread can be created 4737 * 4738 * Check to see if the current task is allowed to create a new io_uring 4739 * kernel polling thread. 4740 */ 4741 static int smack_uring_sqpoll(void) 4742 { 4743 if (smack_privileged_cred(CAP_MAC_ADMIN, current_cred())) 4744 return 0; 4745 4746 return -EPERM; 4747 } 4748 4749 /** 4750 * smack_uring_cmd - check on file operations for io_uring 4751 * @ioucmd: the command in question 4752 * 4753 * Make a best guess about whether a io_uring "command" should 4754 * be allowed. Use the same logic used for determining if the 4755 * file could be opened for read in the absence of better criteria. 4756 */ 4757 static int smack_uring_cmd(struct io_uring_cmd *ioucmd) 4758 { 4759 struct file *file = ioucmd->file; 4760 struct smk_audit_info ad; 4761 struct task_smack *tsp; 4762 struct inode *inode; 4763 int rc; 4764 4765 if (!file) 4766 return -EINVAL; 4767 4768 tsp = smack_cred(file->f_cred); 4769 inode = file_inode(file); 4770 4771 smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); 4772 smk_ad_setfield_u_fs_path(&ad, file->f_path); 4773 rc = smk_tskacc(tsp, smk_of_inode(inode), MAY_READ, &ad); 4774 rc = smk_bu_credfile(file->f_cred, file, MAY_READ, rc); 4775 4776 return rc; 4777 } 4778 4779 #endif /* CONFIG_IO_URING */ 4780 4781 struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = { 4782 .lbs_cred = sizeof(struct task_smack), 4783 .lbs_file = sizeof(struct smack_known *), 4784 .lbs_inode = sizeof(struct inode_smack), 4785 .lbs_ipc = sizeof(struct smack_known *), 4786 .lbs_msg_msg = sizeof(struct smack_known *), 4787 .lbs_superblock = sizeof(struct superblock_smack), 4788 }; 4789 4790 static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { 4791 LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check), 4792 LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme), 4793 LSM_HOOK_INIT(syslog, smack_syslog), 4794 4795 LSM_HOOK_INIT(fs_context_dup, smack_fs_context_dup), 4796 LSM_HOOK_INIT(fs_context_parse_param, smack_fs_context_parse_param), 4797 4798 LSM_HOOK_INIT(sb_alloc_security, smack_sb_alloc_security), 4799 LSM_HOOK_INIT(sb_free_mnt_opts, smack_free_mnt_opts), 4800 LSM_HOOK_INIT(sb_eat_lsm_opts, smack_sb_eat_lsm_opts), 4801 LSM_HOOK_INIT(sb_statfs, smack_sb_statfs), 4802 LSM_HOOK_INIT(sb_set_mnt_opts, smack_set_mnt_opts), 4803 4804 LSM_HOOK_INIT(bprm_creds_for_exec, smack_bprm_creds_for_exec), 4805 4806 LSM_HOOK_INIT(inode_alloc_security, smack_inode_alloc_security), 4807 LSM_HOOK_INIT(inode_init_security, smack_inode_init_security), 4808 LSM_HOOK_INIT(inode_link, smack_inode_link), 4809 LSM_HOOK_INIT(inode_unlink, smack_inode_unlink), 4810 LSM_HOOK_INIT(inode_rmdir, smack_inode_rmdir), 4811 LSM_HOOK_INIT(inode_rename, smack_inode_rename), 4812 LSM_HOOK_INIT(inode_permission, smack_inode_permission), 4813 LSM_HOOK_INIT(inode_setattr, smack_inode_setattr), 4814 LSM_HOOK_INIT(inode_getattr, smack_inode_getattr), 4815 LSM_HOOK_INIT(inode_setxattr, smack_inode_setxattr), 4816 LSM_HOOK_INIT(inode_post_setxattr, smack_inode_post_setxattr), 4817 LSM_HOOK_INIT(inode_getxattr, smack_inode_getxattr), 4818 LSM_HOOK_INIT(inode_removexattr, smack_inode_removexattr), 4819 LSM_HOOK_INIT(inode_getsecurity, smack_inode_getsecurity), 4820 LSM_HOOK_INIT(inode_setsecurity, smack_inode_setsecurity), 4821 LSM_HOOK_INIT(inode_listsecurity, smack_inode_listsecurity), 4822 LSM_HOOK_INIT(inode_getsecid, smack_inode_getsecid), 4823 4824 LSM_HOOK_INIT(file_alloc_security, smack_file_alloc_security), 4825 LSM_HOOK_INIT(file_ioctl, smack_file_ioctl), 4826 LSM_HOOK_INIT(file_lock, smack_file_lock), 4827 LSM_HOOK_INIT(file_fcntl, smack_file_fcntl), 4828 LSM_HOOK_INIT(mmap_file, smack_mmap_file), 4829 LSM_HOOK_INIT(mmap_addr, cap_mmap_addr), 4830 LSM_HOOK_INIT(file_set_fowner, smack_file_set_fowner), 4831 LSM_HOOK_INIT(file_send_sigiotask, smack_file_send_sigiotask), 4832 LSM_HOOK_INIT(file_receive, smack_file_receive), 4833 4834 LSM_HOOK_INIT(file_open, smack_file_open), 4835 4836 LSM_HOOK_INIT(cred_alloc_blank, smack_cred_alloc_blank), 4837 LSM_HOOK_INIT(cred_free, smack_cred_free), 4838 LSM_HOOK_INIT(cred_prepare, smack_cred_prepare), 4839 LSM_HOOK_INIT(cred_transfer, smack_cred_transfer), 4840 LSM_HOOK_INIT(cred_getsecid, smack_cred_getsecid), 4841 LSM_HOOK_INIT(kernel_act_as, smack_kernel_act_as), 4842 LSM_HOOK_INIT(kernel_create_files_as, smack_kernel_create_files_as), 4843 LSM_HOOK_INIT(task_setpgid, smack_task_setpgid), 4844 LSM_HOOK_INIT(task_getpgid, smack_task_getpgid), 4845 LSM_HOOK_INIT(task_getsid, smack_task_getsid), 4846 LSM_HOOK_INIT(current_getsecid_subj, smack_current_getsecid_subj), 4847 LSM_HOOK_INIT(task_getsecid_obj, smack_task_getsecid_obj), 4848 LSM_HOOK_INIT(task_setnice, smack_task_setnice), 4849 LSM_HOOK_INIT(task_setioprio, smack_task_setioprio), 4850 LSM_HOOK_INIT(task_getioprio, smack_task_getioprio), 4851 LSM_HOOK_INIT(task_setscheduler, smack_task_setscheduler), 4852 LSM_HOOK_INIT(task_getscheduler, smack_task_getscheduler), 4853 LSM_HOOK_INIT(task_movememory, smack_task_movememory), 4854 LSM_HOOK_INIT(task_kill, smack_task_kill), 4855 LSM_HOOK_INIT(task_to_inode, smack_task_to_inode), 4856 4857 LSM_HOOK_INIT(ipc_permission, smack_ipc_permission), 4858 LSM_HOOK_INIT(ipc_getsecid, smack_ipc_getsecid), 4859 4860 LSM_HOOK_INIT(msg_msg_alloc_security, smack_msg_msg_alloc_security), 4861 4862 LSM_HOOK_INIT(msg_queue_alloc_security, smack_ipc_alloc_security), 4863 LSM_HOOK_INIT(msg_queue_associate, smack_msg_queue_associate), 4864 LSM_HOOK_INIT(msg_queue_msgctl, smack_msg_queue_msgctl), 4865 LSM_HOOK_INIT(msg_queue_msgsnd, smack_msg_queue_msgsnd), 4866 LSM_HOOK_INIT(msg_queue_msgrcv, smack_msg_queue_msgrcv), 4867 4868 LSM_HOOK_INIT(shm_alloc_security, smack_ipc_alloc_security), 4869 LSM_HOOK_INIT(shm_associate, smack_shm_associate), 4870 LSM_HOOK_INIT(shm_shmctl, smack_shm_shmctl), 4871 LSM_HOOK_INIT(shm_shmat, smack_shm_shmat), 4872 4873 LSM_HOOK_INIT(sem_alloc_security, smack_ipc_alloc_security), 4874 LSM_HOOK_INIT(sem_associate, smack_sem_associate), 4875 LSM_HOOK_INIT(sem_semctl, smack_sem_semctl), 4876 LSM_HOOK_INIT(sem_semop, smack_sem_semop), 4877 4878 LSM_HOOK_INIT(d_instantiate, smack_d_instantiate), 4879 4880 LSM_HOOK_INIT(getprocattr, smack_getprocattr), 4881 LSM_HOOK_INIT(setprocattr, smack_setprocattr), 4882 4883 LSM_HOOK_INIT(unix_stream_connect, smack_unix_stream_connect), 4884 LSM_HOOK_INIT(unix_may_send, smack_unix_may_send), 4885 4886 LSM_HOOK_INIT(socket_post_create, smack_socket_post_create), 4887 LSM_HOOK_INIT(socket_socketpair, smack_socket_socketpair), 4888 #ifdef SMACK_IPV6_PORT_LABELING 4889 LSM_HOOK_INIT(socket_bind, smack_socket_bind), 4890 #endif 4891 LSM_HOOK_INIT(socket_connect, smack_socket_connect), 4892 LSM_HOOK_INIT(socket_sendmsg, smack_socket_sendmsg), 4893 LSM_HOOK_INIT(socket_sock_rcv_skb, smack_socket_sock_rcv_skb), 4894 LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream), 4895 LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram), 4896 LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security), 4897 LSM_HOOK_INIT(sk_free_security, smack_sk_free_security), 4898 LSM_HOOK_INIT(sk_clone_security, smack_sk_clone_security), 4899 LSM_HOOK_INIT(sock_graft, smack_sock_graft), 4900 LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request), 4901 LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone), 4902 4903 /* key management security hooks */ 4904 #ifdef CONFIG_KEYS 4905 LSM_HOOK_INIT(key_alloc, smack_key_alloc), 4906 LSM_HOOK_INIT(key_free, smack_key_free), 4907 LSM_HOOK_INIT(key_permission, smack_key_permission), 4908 LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity), 4909 #ifdef CONFIG_KEY_NOTIFICATIONS 4910 LSM_HOOK_INIT(watch_key, smack_watch_key), 4911 #endif 4912 #endif /* CONFIG_KEYS */ 4913 4914 #ifdef CONFIG_WATCH_QUEUE 4915 LSM_HOOK_INIT(post_notification, smack_post_notification), 4916 #endif 4917 4918 /* Audit hooks */ 4919 #ifdef CONFIG_AUDIT 4920 LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init), 4921 LSM_HOOK_INIT(audit_rule_known, smack_audit_rule_known), 4922 LSM_HOOK_INIT(audit_rule_match, smack_audit_rule_match), 4923 #endif /* CONFIG_AUDIT */ 4924 4925 LSM_HOOK_INIT(ismaclabel, smack_ismaclabel), 4926 LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx), 4927 LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid), 4928 LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx), 4929 LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx), 4930 LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx), 4931 LSM_HOOK_INIT(inode_copy_up, smack_inode_copy_up), 4932 LSM_HOOK_INIT(inode_copy_up_xattr, smack_inode_copy_up_xattr), 4933 LSM_HOOK_INIT(dentry_create_files_as, smack_dentry_create_files_as), 4934 #ifdef CONFIG_IO_URING 4935 LSM_HOOK_INIT(uring_override_creds, smack_uring_override_creds), 4936 LSM_HOOK_INIT(uring_sqpoll, smack_uring_sqpoll), 4937 LSM_HOOK_INIT(uring_cmd, smack_uring_cmd), 4938 #endif 4939 }; 4940 4941 4942 static __init void init_smack_known_list(void) 4943 { 4944 /* 4945 * Initialize rule list locks 4946 */ 4947 mutex_init(&smack_known_huh.smk_rules_lock); 4948 mutex_init(&smack_known_hat.smk_rules_lock); 4949 mutex_init(&smack_known_floor.smk_rules_lock); 4950 mutex_init(&smack_known_star.smk_rules_lock); 4951 mutex_init(&smack_known_web.smk_rules_lock); 4952 /* 4953 * Initialize rule lists 4954 */ 4955 INIT_LIST_HEAD(&smack_known_huh.smk_rules); 4956 INIT_LIST_HEAD(&smack_known_hat.smk_rules); 4957 INIT_LIST_HEAD(&smack_known_star.smk_rules); 4958 INIT_LIST_HEAD(&smack_known_floor.smk_rules); 4959 INIT_LIST_HEAD(&smack_known_web.smk_rules); 4960 /* 4961 * Create the known labels list 4962 */ 4963 smk_insert_entry(&smack_known_huh); 4964 smk_insert_entry(&smack_known_hat); 4965 smk_insert_entry(&smack_known_star); 4966 smk_insert_entry(&smack_known_floor); 4967 smk_insert_entry(&smack_known_web); 4968 } 4969 4970 /** 4971 * smack_init - initialize the smack system 4972 * 4973 * Returns 0 on success, -ENOMEM is there's no memory 4974 */ 4975 static __init int smack_init(void) 4976 { 4977 struct cred *cred = (struct cred *) current->cred; 4978 struct task_smack *tsp; 4979 4980 smack_rule_cache = KMEM_CACHE(smack_rule, 0); 4981 if (!smack_rule_cache) 4982 return -ENOMEM; 4983 4984 /* 4985 * Set the security state for the initial task. 4986 */ 4987 tsp = smack_cred(cred); 4988 init_task_smack(tsp, &smack_known_floor, &smack_known_floor); 4989 4990 /* 4991 * Register with LSM 4992 */ 4993 security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack"); 4994 smack_enabled = 1; 4995 4996 pr_info("Smack: Initializing.\n"); 4997 #ifdef CONFIG_SECURITY_SMACK_NETFILTER 4998 pr_info("Smack: Netfilter enabled.\n"); 4999 #endif 5000 #ifdef SMACK_IPV6_PORT_LABELING 5001 pr_info("Smack: IPv6 port labeling enabled.\n"); 5002 #endif 5003 #ifdef SMACK_IPV6_SECMARK_LABELING 5004 pr_info("Smack: IPv6 Netfilter enabled.\n"); 5005 #endif 5006 5007 /* initialize the smack_known_list */ 5008 init_smack_known_list(); 5009 5010 return 0; 5011 } 5012 5013 /* 5014 * Smack requires early initialization in order to label 5015 * all processes and objects when they are created. 5016 */ 5017 DEFINE_LSM(smack) = { 5018 .name = "smack", 5019 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE, 5020 .blobs = &smack_blob_sizes, 5021 .init = smack_init, 5022 }; 5023