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 (unused) */ 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 184enum { 185 Opt_error = -1, 186 Opt_fsdefault = 0, 187 Opt_fsfloor = 1, 188 Opt_fshat = 2, 189 Opt_fsroot = 3, 190 Opt_fstransmute = 4, 191}; 192 193#define SMACK_DELETE_OPTION "-DELETE" 194#define SMACK_CIPSO_OPTION "-CIPSO" 195 196/* 197 * CIPSO defaults. 198 */ 199#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ 200#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ 201#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ 202#define SMACK_CIPSO_MAPPED_DEFAULT 251 /* Also arbitrary */ 203#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ 204/* 205 * CIPSO 2.2 standard is 239, but Smack wants to use the 206 * categories in a structured way that limits the value to 207 * the bits in 23 bytes, hence the unusual number. 208 */ 209#define SMACK_CIPSO_MAXCATNUM 184 /* 23 * 8 */ 210 211/* 212 * Ptrace rules 213 */ 214#define SMACK_PTRACE_DEFAULT 0 215#define SMACK_PTRACE_EXACT 1 216#define SMACK_PTRACE_DRACONIAN 2 217#define SMACK_PTRACE_MAX SMACK_PTRACE_DRACONIAN 218 219/* 220 * Flags for untraditional access modes. 221 * It shouldn't be necessary to avoid conflicts with definitions 222 * in fs.h, but do so anyway. 223 */ 224#define MAY_TRANSMUTE 0x00001000 /* Controls directory labeling */ 225#define MAY_LOCK 0x00002000 /* Locks should be writes, but ... */ 226#define MAY_BRINGUP 0x00004000 /* Report use of this rule */ 227 228/* 229 * The policy for delivering signals is configurable. 230 * It is usually "write", but can be "append". 231 */ 232#ifdef CONFIG_SECURITY_SMACK_APPEND_SIGNALS 233#define MAY_DELIVER MAY_APPEND /* Signal delivery requires append */ 234#else 235#define MAY_DELIVER MAY_WRITE /* Signal delivery requires write */ 236#endif 237 238#define SMACK_BRINGUP_ALLOW 1 /* Allow bringup mode */ 239#define SMACK_UNCONFINED_SUBJECT 2 /* Allow unconfined label */ 240#define SMACK_UNCONFINED_OBJECT 3 /* Allow unconfined label */ 241 242/* 243 * Just to make the common cases easier to deal with 244 */ 245#define MAY_ANYREAD (MAY_READ | MAY_EXEC) 246#define MAY_READWRITE (MAY_READ | MAY_WRITE) 247#define MAY_NOT 0 248 249/* 250 * Number of access types used by Smack (rwxatlb) 251 */ 252#define SMK_NUM_ACCESS_TYPE 7 253 254/* SMACK data */ 255struct smack_audit_data { 256 const char *function; 257 char *subject; 258 char *object; 259 char *request; 260 int result; 261}; 262 263/* 264 * Smack audit data; is empty if CONFIG_AUDIT not set 265 * to save some stack 266 */ 267struct smk_audit_info { 268#ifdef CONFIG_AUDIT 269 struct common_audit_data a; 270 struct smack_audit_data sad; 271#endif 272}; 273 274/* 275 * These functions are in smack_access.c 276 */ 277int smk_access_entry(char *, char *, struct list_head *); 278int smk_access(struct smack_known *, struct smack_known *, 279 int, struct smk_audit_info *); 280int smk_tskacc(struct task_smack *, struct smack_known *, 281 u32, struct smk_audit_info *); 282int smk_curacc(struct smack_known *, u32, struct smk_audit_info *); 283struct smack_known *smack_from_secid(const u32); 284char *smk_parse_smack(const char *string, int len); 285int smk_netlbl_mls(int, char *, struct netlbl_lsm_secattr *, int); 286struct smack_known *smk_import_entry(const char *, int); 287void smk_insert_entry(struct smack_known *skp); 288struct smack_known *smk_find_entry(const char *); 289bool smack_privileged(int cap); 290bool smack_privileged_cred(int cap, const struct cred *cred); 291void smk_destroy_label_list(struct list_head *list); 292int smack_populate_secattr(struct smack_known *skp); 293 294/* 295 * Shared data. 296 */ 297extern int smack_enabled __initdata; 298extern int smack_cipso_direct; 299extern int smack_cipso_mapped; 300extern struct smack_known *smack_net_ambient; 301extern struct smack_known *smack_syslog_label; 302#ifdef CONFIG_SECURITY_SMACK_BRINGUP 303extern struct smack_known *smack_unconfined; 304#endif 305extern int smack_ptrace_rule; 306extern struct lsm_blob_sizes smack_blob_sizes; 307 308extern struct smack_known smack_known_floor; 309extern struct smack_known smack_known_hat; 310extern struct smack_known smack_known_huh; 311extern struct smack_known smack_known_star; 312extern struct smack_known smack_known_web; 313 314extern struct mutex smack_known_lock; 315extern struct list_head smack_known_list; 316extern struct list_head smk_net4addr_list; 317extern struct list_head smk_net6addr_list; 318 319extern struct mutex smack_onlycap_lock; 320extern struct list_head smack_onlycap_list; 321 322#define SMACK_HASH_SLOTS 16 323extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; 324extern struct kmem_cache *smack_rule_cache; 325 326static inline struct task_smack *smack_cred(const struct cred *cred) 327{ 328 return cred->security + smack_blob_sizes.lbs_cred; 329} 330 331static inline struct smack_known **smack_file(const struct file *file) 332{ 333 return (struct smack_known **)(file->f_security + 334 smack_blob_sizes.lbs_file); 335} 336 337static inline struct inode_smack *smack_inode(const struct inode *inode) 338{ 339 return inode->i_security + smack_blob_sizes.lbs_inode; 340} 341 342static inline struct smack_known **smack_msg_msg(const struct msg_msg *msg) 343{ 344 return msg->security + smack_blob_sizes.lbs_msg_msg; 345} 346 347static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc) 348{ 349 return ipc->security + smack_blob_sizes.lbs_ipc; 350} 351 352static inline struct superblock_smack *smack_superblock( 353 const struct super_block *superblock) 354{ 355 return superblock->s_security + smack_blob_sizes.lbs_superblock; 356} 357 358/* 359 * Is the directory transmuting? 360 */ 361static inline int smk_inode_transmutable(const struct inode *isp) 362{ 363 struct inode_smack *sip = smack_inode(isp); 364 return (sip->smk_flags & SMK_INODE_TRANSMUTE) != 0; 365} 366 367/* 368 * Present a pointer to the smack label entry in an inode blob. 369 */ 370static inline struct smack_known *smk_of_inode(const struct inode *isp) 371{ 372 struct inode_smack *sip = smack_inode(isp); 373 return sip->smk_inode; 374} 375 376/* 377 * Present a pointer to the smack label entry in an task blob. 378 */ 379static inline struct smack_known *smk_of_task(const struct task_smack *tsp) 380{ 381 return tsp->smk_task; 382} 383 384static inline struct smack_known *smk_of_task_struct_obj( 385 const struct task_struct *t) 386{ 387 struct smack_known *skp; 388 const struct cred *cred; 389 390 rcu_read_lock(); 391 392 cred = __task_cred(t); 393 skp = smk_of_task(smack_cred(cred)); 394 395 rcu_read_unlock(); 396 397 return skp; 398} 399 400/* 401 * Present a pointer to the forked smack label entry in an task blob. 402 */ 403static inline struct smack_known *smk_of_forked(const struct task_smack *tsp) 404{ 405 return tsp->smk_forked; 406} 407 408/* 409 * Present a pointer to the smack label in the current task blob. 410 */ 411static inline struct smack_known *smk_of_current(void) 412{ 413 return smk_of_task(smack_cred(current_cred())); 414} 415 416/* 417 * logging functions 418 */ 419#define SMACK_AUDIT_DENIED 0x1 420#define SMACK_AUDIT_ACCEPT 0x2 421extern int log_policy; 422 423void smack_log(char *subject_label, char *object_label, 424 int request, 425 int result, struct smk_audit_info *auditdata); 426 427#ifdef CONFIG_AUDIT 428 429/* 430 * some inline functions to set up audit data 431 * they do nothing if CONFIG_AUDIT is not set 432 * 433 */ 434static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 435 char type) 436{ 437 memset(&a->sad, 0, sizeof(a->sad)); 438 a->a.type = type; 439 a->a.smack_audit_data = &a->sad; 440 a->a.smack_audit_data->function = func; 441} 442 443static inline void smk_ad_init_net(struct smk_audit_info *a, const char *func, 444 char type, struct lsm_network_audit *net) 445{ 446 smk_ad_init(a, func, type); 447 memset(net, 0, sizeof(*net)); 448 a->a.u.net = net; 449} 450 451static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 452 struct task_struct *t) 453{ 454 a->a.u.tsk = t; 455} 456static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 457 struct dentry *d) 458{ 459 a->a.u.dentry = d; 460} 461static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 462 struct inode *i) 463{ 464 a->a.u.inode = i; 465} 466static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 467 struct path p) 468{ 469 a->a.u.path = p; 470} 471static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 472 struct sock *sk) 473{ 474 a->a.u.net->sk = sk; 475} 476 477#else /* no AUDIT */ 478 479static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 480 char type) 481{ 482} 483static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 484 struct task_struct *t) 485{ 486} 487static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 488 struct dentry *d) 489{ 490} 491static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 492 struct inode *i) 493{ 494} 495static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 496 struct path p) 497{ 498} 499static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 500 struct sock *sk) 501{ 502} 503#endif 504 505#endif /* _SECURITY_SMACK_H */ 506