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 34 struct 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 43 struct 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 */ 52 struct 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 */ 63 struct 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 */ 74 struct smack_cipso { 75 int smk_level; 76 char smk_catset[SMK_LABELLEN]; 77 }; 78 79 /* 80 * An entry in the table identifying hosts. 81 */ 82 struct 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 */ 110 struct 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 /* 127 * xattr names 128 */ 129 #define XATTR_SMACK_SUFFIX "SMACK64" 130 #define XATTR_SMACK_IPIN "SMACK64IPIN" 131 #define XATTR_SMACK_IPOUT "SMACK64IPOUT" 132 #define XATTR_NAME_SMACK XATTR_SECURITY_PREFIX XATTR_SMACK_SUFFIX 133 #define XATTR_NAME_SMACKIPIN XATTR_SECURITY_PREFIX XATTR_SMACK_IPIN 134 #define XATTR_NAME_SMACKIPOUT XATTR_SECURITY_PREFIX XATTR_SMACK_IPOUT 135 136 #define SMACK_CIPSO_OPTION "-CIPSO" 137 138 /* 139 * How communications on this socket are treated. 140 * Usually it's determined by the underlying netlabel code 141 * but there are certain cases, including single label hosts 142 * and potentially single label interfaces for which the 143 * treatment can not be known in advance. 144 * 145 * The possibility of additional labeling schemes being 146 * introduced in the future exists as well. 147 */ 148 #define SMACK_UNLABELED_SOCKET 0 149 #define SMACK_CIPSO_SOCKET 1 150 151 /* 152 * smackfs magic number 153 * smackfs macic number 154 */ 155 #define SMACK_MAGIC 0x43415d53 /* "SMAC" */ 156 157 /* 158 * A limit on the number of entries in the lists 159 * makes some of the list administration easier. 160 */ 161 #define SMACK_LIST_MAX 10000 162 163 /* 164 * CIPSO defaults. 165 */ 166 #define SMACK_CIPSO_DOI_DEFAULT 3 /* Historical */ 167 #define SMACK_CIPSO_DOI_INVALID -1 /* Not a DOI */ 168 #define SMACK_CIPSO_DIRECT_DEFAULT 250 /* Arbitrary */ 169 #define SMACK_CIPSO_MAXCATVAL 63 /* Bigger gets harder */ 170 #define SMACK_CIPSO_MAXLEVEL 255 /* CIPSO 2.2 standard */ 171 #define SMACK_CIPSO_MAXCATNUM 239 /* CIPSO 2.2 standard */ 172 173 /* 174 * Just to make the common cases easier to deal with 175 */ 176 #define MAY_ANY (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) 177 #define MAY_ANYREAD (MAY_READ | MAY_EXEC) 178 #define MAY_ANYWRITE (MAY_WRITE | MAY_APPEND) 179 #define MAY_READWRITE (MAY_READ | MAY_WRITE) 180 #define MAY_NOT 0 181 182 /* 183 * Number of access types used by Smack (rwxa) 184 */ 185 #define SMK_NUM_ACCESS_TYPE 4 186 187 /* 188 * Smack audit data; is empty if CONFIG_AUDIT not set 189 * to save some stack 190 */ 191 struct smk_audit_info { 192 #ifdef CONFIG_AUDIT 193 struct common_audit_data a; 194 #endif 195 }; 196 /* 197 * These functions are in smack_lsm.c 198 */ 199 struct inode_smack *new_inode_smack(char *); 200 201 /* 202 * These functions are in smack_access.c 203 */ 204 int smk_access(char *, char *, int, struct smk_audit_info *); 205 int smk_curacc(char *, u32, struct smk_audit_info *); 206 int smack_to_cipso(const char *, struct smack_cipso *); 207 void smack_from_cipso(u32, char *, char *); 208 char *smack_from_secid(const u32); 209 char *smk_import(const char *, int); 210 struct smack_known *smk_import_entry(const char *, int); 211 u32 smack_to_secid(const char *); 212 213 /* 214 * Shared data. 215 */ 216 extern int smack_cipso_direct; 217 extern char *smack_net_ambient; 218 extern char *smack_onlycap; 219 extern const char *smack_cipso_option; 220 221 extern struct smack_known smack_known_floor; 222 extern struct smack_known smack_known_hat; 223 extern struct smack_known smack_known_huh; 224 extern struct smack_known smack_known_invalid; 225 extern struct smack_known smack_known_star; 226 extern struct smack_known smack_known_web; 227 228 extern struct list_head smack_known_list; 229 extern struct list_head smack_rule_list; 230 extern struct list_head smk_netlbladdr_list; 231 232 extern struct security_operations smack_ops; 233 234 /* 235 * Stricly for CIPSO level manipulation. 236 * Set the category bit number in a smack label sized buffer. 237 */ 238 static inline void smack_catset_bit(int cat, char *catsetp) 239 { 240 if (cat > SMK_LABELLEN * 8) 241 return; 242 243 catsetp[(cat - 1) / 8] |= 0x80 >> ((cat - 1) % 8); 244 } 245 246 /* 247 * Present a pointer to the smack label in an inode blob. 248 */ 249 static inline char *smk_of_inode(const struct inode *isp) 250 { 251 struct inode_smack *sip = isp->i_security; 252 return sip->smk_inode; 253 } 254 255 /* 256 * logging functions 257 */ 258 #define SMACK_AUDIT_DENIED 0x1 259 #define SMACK_AUDIT_ACCEPT 0x2 260 extern int log_policy; 261 262 void smack_log(char *subject_label, char *object_label, 263 int request, 264 int result, struct smk_audit_info *auditdata); 265 266 #ifdef CONFIG_AUDIT 267 268 /* 269 * some inline functions to set up audit data 270 * they do nothing if CONFIG_AUDIT is not set 271 * 272 */ 273 static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 274 char type) 275 { 276 memset(a, 0, sizeof(*a)); 277 a->a.type = type; 278 a->a.smack_audit_data.function = func; 279 } 280 281 static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 282 struct task_struct *t) 283 { 284 a->a.u.tsk = t; 285 } 286 static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 287 struct dentry *d) 288 { 289 a->a.u.fs.path.dentry = d; 290 } 291 static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, 292 struct vfsmount *m) 293 { 294 a->a.u.fs.path.mnt = m; 295 } 296 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 297 struct inode *i) 298 { 299 a->a.u.fs.inode = i; 300 } 301 static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 302 struct path p) 303 { 304 a->a.u.fs.path = p; 305 } 306 static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 307 struct sock *sk) 308 { 309 a->a.u.net.sk = sk; 310 } 311 312 #else /* no AUDIT */ 313 314 static inline void smk_ad_init(struct smk_audit_info *a, const char *func, 315 char type) 316 { 317 } 318 static inline void smk_ad_setfield_u_tsk(struct smk_audit_info *a, 319 struct task_struct *t) 320 { 321 } 322 static inline void smk_ad_setfield_u_fs_path_dentry(struct smk_audit_info *a, 323 struct dentry *d) 324 { 325 } 326 static inline void smk_ad_setfield_u_fs_path_mnt(struct smk_audit_info *a, 327 struct vfsmount *m) 328 { 329 } 330 static inline void smk_ad_setfield_u_fs_inode(struct smk_audit_info *a, 331 struct inode *i) 332 { 333 } 334 static inline void smk_ad_setfield_u_fs_path(struct smk_audit_info *a, 335 struct path p) 336 { 337 } 338 static inline void smk_ad_setfield_u_net_sk(struct smk_audit_info *a, 339 struct sock *sk) 340 { 341 } 342 #endif 343 344 #endif /* _SECURITY_SMACK_H */ 345