1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> 4 * 5 * Author: 6 * Casey Schaufler <casey@schaufler-ca.com> 7 */ 8 9#ifndef _SECURITY_SMACK_H 10#define _SECURITY_SMACK_H 11 12#include <linux/capability.h> 13#include <linux/spinlock.h> 14#include <linux/lsm_hooks.h> 15#include <linux/in.h> 16#if IS_ENABLED(CONFIG_IPV6) 17#include <linux/in6.h> 18#endif /* CONFIG_IPV6 */ 19#include <net/netlabel.h> 20#include <linux/list.h> 21#include <linux/rculist.h> 22#include <linux/lsm_audit.h> 23#include <linux/msg.h> 24 25/* 26 * Use IPv6 port labeling if IPv6 is enabled and secmarks 27 * are not being used. 28 */ 29#if IS_ENABLED(CONFIG_IPV6) && !defined(CONFIG_SECURITY_SMACK_NETFILTER) 30#define SMACK_IPV6_PORT_LABELING 1 31#endif 32 33#if IS_ENABLED(CONFIG_IPV6) && defined(CONFIG_SECURITY_SMACK_NETFILTER) 34#define SMACK_IPV6_SECMARK_LABELING 1 35#endif 36 37/* 38 * Smack labels were limited to 23 characters for a long time. 39 */ 40#define SMK_LABELLEN 24 41#define SMK_LONGLABEL 256 42 43/* 44 * This is the repository for labels seen so that it is 45 * not necessary to keep allocating tiny chuncks of memory 46 * and so that they can be shared. 47 * 48 * Labels are never modified in place. Anytime a label 49 * is imported (e.g. xattrset on a file) the list is checked 50 * for it and it is added if it doesn't exist. The address 51 * is passed out in either case. Entries are added, but 52 * never deleted. 53 * 54 * Since labels are hanging around anyway it doesn't 55 * hurt to maintain a secid for those awkward situations 56 * where kernel components that ought to use LSM independent 57 * interfaces don't. The secid should go away when all of 58 * these components have been repaired. 59 * 60 * The cipso value associated with the label gets stored here, too. 61 * 62 * Keep the access rules for this subject label here so that 63 * the entire set of rules does not need to be examined every 64 * time. 65 */ 66struct smack_known { 67 struct list_head list; 68 struct hlist_node smk_hashed; 69 char *smk_known; 70 u32 smk_secid; 71 struct netlbl_lsm_secattr smk_netlabel; /* on wire labels */ 72 struct list_head smk_rules; /* access rules */ 73 struct mutex smk_rules_lock; /* lock for rules */ 74}; 75 76/* 77 * Maximum number of bytes for the levels in a CIPSO IP option. 78 * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is 79 * bigger than can be used, and 24 is the next lower multiple 80 * of 8, and there are too many issues if there isn't space set 81 * aside for the terminating null byte. 82 */ 83#define SMK_CIPSOLEN 24 84 85struct superblock_smack { 86 struct smack_known *smk_root; 87 struct smack_known *smk_floor; 88 struct smack_known *smk_hat; 89 struct smack_known *smk_default; 90 int smk_flags; 91}; 92 93/* 94 * Superblock flags 95 */ 96#define SMK_SB_INITIALIZED 0x01 97#define SMK_SB_UNTRUSTED 0x02 98 99struct socket_smack { 100 struct smack_known *smk_out; /* outbound label */ 101 struct smack_known *smk_in; /* inbound label */ 102 struct smack_known *smk_packet; /* TCP peer label */ 103 int smk_state; /* netlabel socket states */ 104}; 105#define SMK_NETLBL_UNSET 0 106#define SMK_NETLBL_UNLABELED 1 107#define SMK_NETLBL_LABELED 2 108#define SMK_NETLBL_REQSKB 3 109 110/* 111 * Inode smack data 112 */ 113struct inode_smack { 114 struct smack_known *smk_inode; /* label of the fso */ 115 struct smack_known *smk_task; /* label of the task */ 116 struct smack_known *smk_mmap; /* label of the mmap domain */ 117 int smk_flags; /* smack inode flags */ 118}; 119 120struct task_smack { 121 struct smack_known *smk_task; /* label for access control */ 122 struct smack_known *smk_forked; /* label when forked */ 123 struct smack_known *smk_transmuted;/* label when transmuted */ 124 struct list_head smk_rules; /* per task access rules */ 125 struct mutex smk_rules_lock; /* lock for the rules */ 126 struct list_head smk_relabel; /* transit allowed labels */ 127}; 128 129#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ 130#define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */ 131#define SMK_INODE_CHANGED 0x04 /* smack was transmuted */ 132#define SMK_INODE_IMPURE 0x08 /* involved in an impure transaction */ 133 134/* 135 * A label access rule. 136 */ 137struct smack_rule { 138 struct list_head list; 139 struct smack_known *smk_subject; 140 struct smack_known *smk_object; 141 int smk_access; 142}; 143 144/* 145 * An entry in the table identifying IPv4 hosts. 146 */ 147struct smk_net4addr { 148 struct list_head list; 149 struct in_addr smk_host; /* network address */ 150 struct in_addr smk_mask; /* network mask */ 151 int smk_masks; /* mask size */ 152 struct smack_known *smk_label; /* label */ 153}; 154 155/* 156 * An entry in the table identifying IPv6 hosts. 157 */ 158struct smk_net6addr { 159 struct list_head list; 160 struct in6_addr smk_host; /* network address */ 161 struct in6_addr smk_mask; /* network mask */ 162 int smk_masks; /* mask size */ 163 struct smack_known *smk_label; /* label */ 164}; 165 166/* 167 * An entry in the table identifying ports. 168 */ 169struct smk_port_label { 170 struct list_head list; 171 struct sock *smk_sock; /* socket initialized on */ 172 unsigned short smk_port; /* the port number */ 173 struct smack_known *smk_in; /* inbound label */ 174 struct smack_known *smk_out; /* outgoing label */ 175 short smk_sock_type; /* Socket type */ 176 short smk_can_reuse; 177}; 178 179struct smack_known_list_elem { 180 struct list_head list; 181 struct smack_known *smk_label; 182}; 183 184/* Super block security struct flags for mount options */ 185#define FSDEFAULT_MNT 0x01 186#define FSFLOOR_MNT 0x02 187#define FSHAT_MNT 0x04 188#define FSROOT_MNT 0x08 189#define FSTRANS_MNT 0x10 190 191#define NUM_SMK_MNT_OPTS 5 192 193enum { 194 Opt_error = -1, 195 Opt_fsdefault = 0, 196 Opt_fsfloor = 1, 197 Opt_fshat = 2, 198 Opt_fsroot = 3, 199 Opt_fstransmute = 4, 200}; 201 202#define SMACK_DELETE_OPTION "-DELETE" 203#define SMACK_CIPSO_OPTION "-CIPSO" 204 205/* 206 * CIPSO defaults. 207 */ 208#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ 209#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ 210#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ 211#define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */ 212#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ 213/* 214 * CIPSO 2.2 standard is 239, but Smack wants to use the 215 * categories in a structured way that limits the value to 216 * the bits in 23 bytes, hence the unusual number. 217 */ 218#define SMACK_CIPSO_MAXCATNUM 184 /* 23 * 8 */ 219 220/* 221 * Ptrace rules 222 */ 223#define SMACK_PTRACE_DEFAULT 0 224#define SMACK_PTRACE_EXACT 1 225#define SMACK_PTRACE_DRACONIAN 2 226#define SMACK_PTRACE_MAX SMACK_PTRACE_DRACONIAN 227 228/* 229 * Flags for untraditional access modes. 230 * It shouldn't be necessary to avoid conflicts with definitions 231 * in fs.h, but do so anyway. 232 */ 233#define MAY_TRANSMUTE 0x00001000 /* Controls directory labeling */ 234#define MAY_LOCK 0x00002000 /* Locks should be writes, but ... */ 235#define MAY_BRINGUP 0x00004000 /* Report use of this rule */ 236 237/* 238 * The policy for delivering signals is configurable. 239 * It is usually "write", but can be "append". 240 */ 241#ifdef CONFIG_SECURITY_SMACK_APPEND_SIGNALS 242#define MAY_DELIVER MAY_APPEND /* Signal delivery requires append */ 243#else 244#define MAY_DELIVER MAY_WRITE /* Signal delivery requires write */ 245#endif 246 247#define SMACK_BRINGUP_ALLOW 1 /* Allow bringup mode */ 248#define SMACK_UNCONFINED_SUBJECT 2 /* Allow unconfined label */ 249#define SMACK_UNCONFINED_OBJECT 3 /* Allow unconfined label */ 250 251/* 252 * Just to make the common cases easier to deal with 253 */ 254#define MAY_ANYREAD (MAY_READ | MAY_EXEC) 255#define MAY_READWRITE (MAY_READ | MAY_WRITE) 256#define MAY_NOT 0 257 258/* 259 * Number of access types used by Smack (rwxatlb) 260 */ 261#define SMK_NUM_ACCESS_TYPE 7 262 263/* SMACK data */ 264struct smack_audit_data { 265 const char *function; 266 char *subject; 267 char *object; 268 char *request; 269 int result; 270}; 271 272/* 273 * Smack audit data; is empty if CONFIG_AUDIT not set 274 * to save some stack 275 */ 276struct smk_audit_info { 277#ifdef CONFIG_AUDIT 278 struct common_audit_data a; 279 struct smack_audit_data sad; 280#endif 281}; 282 283/* 284 * These functions are in smack_access.c 285 */ 286int smk_access_entry(char *, char *, struct list_head *); 287int smk_access(struct smack_known *, struct smack_known *, 288 int, struct smk_audit_info *); 289int smk_tskacc(struct task_smack *, struct smack_known *, 290 u32, struct smk_audit_info *); 291int smk_curacc(struct smack_known *, u32, struct smk_audit_info *); 292struct smack_known *smack_from_secid(const u32); 293char *smk_parse_smack(const char *string, int len); 294int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int); 295struct smack_known *smk_import_entry(const char *, int); 296void smk_insert_entry(struct smack_known *skp); 297struct smack_known *smk_find_entry(const char *); 298bool smack_privileged(int cap); 299bool smack_privileged_cred(int cap, const struct cred *cred); 300void smk_destroy_label_list(struct list_head *list); 301int smack_populate_secattr(struct smack_known *skp); 302 303/* 304 * Shared data. 305 */ 306extern int smack_enabled; 307extern int smack_cipso_direct; 308extern int smack_cipso_mapped; 309extern struct smack_known *smack_net_ambient; 310extern struct smack_known *smack_syslog_label; 311#ifdef CONFIG_SECURITY_SMACK_BRINGUP 312extern struct smack_known *smack_unconfined; 313#endif 314extern int smack_ptrace_rule; 315extern struct lsm_blob_sizes smack_blob_sizes; 316 317extern struct smack_known smack_known_floor; 318extern struct smack_known smack_known_hat; 319extern struct smack_known smack_known_huh; 320extern struct smack_known smack_known_star; 321extern struct smack_known smack_known_web; 322 323extern struct mutex smack_known_lock; 324extern struct list_head smack_known_list; 325extern struct list_head smk_net4addr_list; 326extern struct list_head smk_net6addr_list; 327 328extern struct mutex smack_onlycap_lock; 329extern struct list_head smack_onlycap_list; 330 331#define SMACK_HASH_SLOTS 16 332extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; 333extern struct kmem_cache *smack_rule_cache; 334 335static inline struct task_smack *smack_cred(const struct cred *cred) 336{ 337 return cred->security + smack_blob_sizes.lbs_cred; 338} 339 340static inline struct smack_known **smack_file(const struct file *file) 341{ 342 return (struct smack_known **)(file->f_security + 343 smack_blob_sizes.lbs_file); 344} 345 346static inline struct inode_smack *smack_inode(const struct inode *inode) 347{ 348 return inode->i_security + smack_blob_sizes.lbs_inode; 349} 350 351static inline struct smack_known **smack_msg_msg(const struct msg_msg *msg) 352{ 353 return msg->security + smack_blob_sizes.lbs_msg_msg; 354} 355 356static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc) 357{ 358 return ipc->security + smack_blob_sizes.lbs_ipc; 359} 360 361/* 362 * Is the directory transmuting? 363 */ 364static inline int smk_inode_transmutable(const struct inode *isp) 365{ 366 struct inode_smack *sip = smack_inode(isp); 367 return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0; 368} 369 370/* 371 * Present a pointer to the smack label entry in an inode blob. 372 */ 373static inline struct smack_known *smk_of_inode(const struct inode *isp) 374{ 375 struct inode_smack *sip = smack_inode(isp); 376 return sip->smk_inode; 377} 378 379/* 380 * Present a pointer to the smack label entry in an task blob. 381 */ 382static inline struct smack_known *smk_of_task(const struct task_smack *tsp) 383{ 384 return tsp->smk_task; 385} 386 387static inline struct smack_known *smk_of_task_struct( 388 const struct task_struct *t) 389{ 390 struct smack_known *skp; 391 const struct cred *cred; 392 393 rcu_read_lock(); 394 395 cred = __task_cred(t); 396 skp = smk_of_task(smack_cred(cred)); 397 398 rcu_read_unlock(); 399 400 return skp; 401} 402 403/* 404 * Present a pointer to the forked smack label entry in an task blob. 405 */ 406static inline struct smack_known *smk_of_forked(const struct task_smack *tsp) 407{ 408 return tsp->smk_forked; 409} 410 411/* 412 * Present a pointer to the smack label in the current task blob. 413 */ 414static inline struct smack_known *smk_of_current(void) 415{ 416 return smk_of_task(smack_cred(current_cred())); 417} 418 419/* 420 * logging functions 421 */ 422#define SMACK_AUDIT_DENIED 0x1 423#define SMACK_AUDIT_ACCEPT 0x2 424extern int log_policy; 425 426void smack_log(char *subject_label, char *object_label, 427 int request, 428 int result, struct smk_audit_info *auditdata); 429 430#ifdef CONFIG_AUDIT 431 432/* 433 * some inline functions to set up audit data 434 * they do nothing if CONFIG_AUDIT is not set 435 * 436 */ 437static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 438 char type) 439{ 440 memset(&a->sad, 0, sizeof(a->sad)); 441 a->a.type = type; 442 a->a.smack_audit_data = &a->sad; 443 a->a.smack_audit_data->function = func; 444} 445 446static inline void smk_ad_init_net(struct smk_audit_info *a, const char *func, 447 char type, struct lsm_network_audit *net) 448{ 449 smk_ad_init(a, func, type); 450 memset(net, 0, sizeof(*net)); 451 a->a.u.net = net; 452} 453 454static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 455 struct task_struct *t) 456{ 457 a->a.u.tsk = t; 458} 459static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 460 struct dentry *d) 461{ 462 a->a.u.dentry = d; 463} 464static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 465 struct inode *i) 466{ 467 a->a.u.inode = i; 468} 469static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 470 struct path p) 471{ 472 a->a.u.path = p; 473} 474static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 475 struct sock *sk) 476{ 477 a->a.u.net->sk = sk; 478} 479 480#else /* no AUDIT */ 481 482static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 483 char type) 484{ 485} 486static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 487 struct task_struct *t) 488{ 489} 490static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 491 struct dentry *d) 492{ 493} 494static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 495 struct inode *i) 496{ 497} 498static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 499 struct path p) 500{ 501} 502static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 503 struct sock *sk) 504{ 505} 506#endif 507 508#endif /* _SECURITY_SMACK_H */ 509