1/* 2 * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation, version 2. 7 * 8 * Author: 9 * Casey Schaufler <casey@schaufler-ca.com> 10 * 11 */ 12 13#ifndef _SECURITY_SMACK_H 14#define _SECURITY_SMACK_H 15 16#include <linux/capability.h> 17#include <linux/spinlock.h> 18#include <linux/security.h> 19#include <linux/in.h> 20#include <net/netlabel.h> 21#include <linux/list.h> 22#include <linux/rculist.h> 23#include <linux/lsm_audit.h> 24 25/* 26 * Why 23? CIPSO is constrained to 30, so a 32 byte buffer is 27 * bigger than can be used, and 24 is the next lower multiple 28 * of 8, and there are too many issues if there isn't space set 29 * aside for the terminating null byte. 30 */ 31#define SMK_MAXLEN 23 32#define SMK_LABELLEN (SMK_MAXLEN+1) 33 34struct superblock_smack { 35 char *smk_root; 36 char *smk_floor; 37 char *smk_hat; 38 char *smk_default; 39 int smk_initialized; 40 spinlock_t smk_sblock; /* for initialization */ 41}; 42 43struct socket_smack { 44 char *smk_out; /* outbound label */ 45 char *smk_in; /* inbound label */ 46 char smk_packet[SMK_LABELLEN]; /* TCP peer label */ 47}; 48 49/* 50 * Inode smack data 51 */ 52struct inode_smack { 53 char *smk_inode; /* label of the fso */ 54 struct mutex smk_lock; /* initialization lock */ 55 int smk_flags; /* smack inode flags */ 56}; 57 58#define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ 59 60/* 61 * A label access rule. 62 */ 63struct smack_rule { 64 struct list_head list; 65 char *smk_subject; 66 char *smk_object; 67 int smk_access; 68}; 69 70/* 71 * An entry in the table mapping smack values to 72 * CIPSO level/category-set values. 73 */ 74struct smack_cipso { 75 int smk_level; 76 char smk_catset[SMK_LABELLEN]; 77}; 78 79/* 80 * An entry in the table identifying hosts. 81 */ 82struct smk_netlbladdr { 83 struct list_head list; 84 struct sockaddr_in smk_host; /* network address */ 85 struct in_addr smk_mask; /* network mask */ 86 char *smk_label; /* label */ 87}; 88 89/* 90 * This is the repository for labels seen so that it is 91 * not necessary to keep allocating tiny chuncks of memory 92 * and so that they can be shared. 93 * 94 * Labels are never modified in place. Anytime a label 95 * is imported (e.g. xattrset on a file) the list is checked 96 * for it and it is added if it doesn't exist. The address 97 * is passed out in either case. Entries are added, but 98 * never deleted. 99 * 100 * Since labels are hanging around anyway it doesn't 101 * hurt to maintain a secid for those awkward situations 102 * where kernel components that ought to use LSM independent 103 * interfaces don't. The secid should go away when all of 104 * these components have been repaired. 105 * 106 * If there is a cipso value associated with the label it 107 * gets stored here, too. This will most likely be rare as 108 * the cipso direct mapping in used internally. 109 */ 110struct smack_known { 111 struct list_head list; 112 char smk_known[SMK_LABELLEN]; 113 u32 smk_secid; 114 struct smack_cipso *smk_cipso; 115 spinlock_t smk_cipsolock; /* for changing cipso map */ 116}; 117 118/* 119 * Mount options 120 */ 121#define SMK_FSDEFAULT "smackfsdef=" 122#define SMK_FSFLOOR "smackfsfloor=" 123#define SMK_FSHAT "smackfshat=" 124#define SMK_FSROOT "smackfsroot=" 125 126#define SMACK_CIPSO_OPTION "-CIPSO" 127 128/* 129 * How communications on this socket are treated. 130 * Usually it's determined by the underlying netlabel code 131 * but there are certain cases, including single label hosts 132 * and potentially single label interfaces for which the 133 * treatment can not be known in advance. 134 * 135 * The possibility of additional labeling schemes being 136 * introduced in the future exists as well. 137 */ 138#define SMACK_UNLABELED_SOCKET 0 139#define SMACK_CIPSO_SOCKET 1 140 141/* 142 * smackfs magic number 143 * smackfs macic number 144 */ 145#define SMACK_MAGIC 0x43415d53 /* "SMAC" */ 146 147/* 148 * A limit on the number of entries in the lists 149 * makes some of the list administration easier. 150 */ 151#define SMACK_LIST_MAX 10000 152 153/* 154 * CIPSO defaults. 155 */ 156#define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ 157#define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ 158#define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ 159#define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */ 160#define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ 161#define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */ 162 163/* 164 * Just to make the common cases easier to deal with 165 */ 166#define MAY_ANY (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) 167#define MAY_ANYREAD (MAY_READ | MAY_EXEC) 168#define MAY_ANYWRITE (MAY_WRITE | MAY_APPEND) 169#define MAY_READWRITE (MAY_READ | MAY_WRITE) 170#define MAY_NOT 0 171 172/* 173 * Number of access types used by Smack (rwxa) 174 */ 175#define SMK_NUM_ACCESS_TYPE 4 176 177/* 178 * Smack audit data; is empty if CONFIG_AUDIT not set 179 * to save some stack 180 */ 181struct smk_audit_info { 182#ifdef CONFIG_AUDIT 183 struct common_audit_data a; 184#endif 185}; 186/* 187 * These functions are in smack_lsm.c 188 */ 189struct inode_smack *new_inode_smack(char *); 190 191/* 192 * These functions are in smack_access.c 193 */ 194int smk_access(char *, char *, int, struct smk_audit_info *); 195int smk_curacc(char *, u32, struct smk_audit_info *); 196int smack_to_cipso(const char *, struct smack_cipso *); 197void smack_from_cipso(u32, char *, char *); 198char *smack_from_secid(const u32); 199char *smk_import(const char *, int); 200struct smack_known *smk_import_entry(const char *, int); 201u32 smack_to_secid(const char *); 202 203/* 204 * Shared data. 205 */ 206extern int smack_cipso_direct; 207extern char *smack_net_ambient; 208extern char *smack_onlycap; 209extern const char *smack_cipso_option; 210 211extern struct smack_known smack_known_floor; 212extern struct smack_known smack_known_hat; 213extern struct smack_known smack_known_huh; 214extern struct smack_known smack_known_invalid; 215extern struct smack_known smack_known_star; 216extern struct smack_known smack_known_web; 217 218extern struct list_head smack_known_list; 219extern struct list_head smack_rule_list; 220extern struct list_head smk_netlbladdr_list; 221 222extern struct security_operations smack_ops; 223 224/* 225 * Stricly for CIPSO level manipulation. 226 * Set the category bit number in a smack label sized buffer. 227 */ 228static inline void smack_catset_bit(int cat, char *catsetp) 229{ 230 if (cat > SMK_LABELLEN * 8) 231 return; 232 233 catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8); 234} 235 236/* 237 * Present a pointer to the smack label in an inode blob. 238 */ 239static inline char *smk_of_inode(const struct inode *isp) 240{ 241 struct inode_smack *sip = isp->i_security; 242 return sip->smk_inode; 243} 244 245/* 246 * logging functions 247 */ 248#define SMACK_AUDIT_DENIED 0x1 249#define SMACK_AUDIT_ACCEPT 0x2 250extern int log_policy; 251 252void smack_log(char *subject_label, char *object_label, 253 int request, 254 int result, struct smk_audit_info *auditdata); 255 256#ifdef CONFIG_AUDIT 257 258/* 259 * some inline functions to set up audit data 260 * they do nothing if CONFIG_AUDIT is not set 261 * 262 */ 263static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 264 char type) 265{ 266 memset(a, 0, sizeof(*a)); 267 a->a.type = type; 268 a->a.smack_audit_data.function = func; 269} 270 271static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 272 struct task_struct *t) 273{ 274 a->a.u.tsk = t; 275} 276static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 277 struct dentry *d) 278{ 279 a->a.u.fs.path.dentry = d; 280} 281static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, 282 struct vfsmount *m) 283{ 284 a->a.u.fs.path.mnt = m; 285} 286static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 287 struct inode *i) 288{ 289 a->a.u.fs.inode = i; 290} 291static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 292 struct path p) 293{ 294 a->a.u.fs.path = p; 295} 296static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 297 struct sock *sk) 298{ 299 a->a.u.net.sk = sk; 300} 301 302#else /* no AUDIT */ 303 304static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 305 char type) 306{ 307} 308static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 309 struct task_struct *t) 310{ 311} 312static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 313 struct dentry *d) 314{ 315} 316static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, 317 struct vfsmount *m) 318{ 319} 320static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 321 struct inode *i) 322{ 323} 324static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 325 struct path p) 326{ 327} 328static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 329 struct sock *sk) 330{ 331} 332#endif 333 334#endif /* _SECURITY_SMACK_H */ 335