1 /* 2 * A policy database (policydb) specifies the 3 * configuration data for the security policy. 4 * 5 * Author : Stephen Smalley, <sds@epoch.ncsc.mil> 6 */ 7 8 /* 9 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> 10 * 11 * Support for enhanced MLS infrastructure. 12 * 13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> 14 * 15 * Added conditional policy language extensions 16 * 17 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. 18 * Copyright (C) 2003 - 2004 Tresys Technology, LLC 19 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation, version 2. 22 */ 23 24 #ifndef _SS_POLICYDB_H_ 25 #define _SS_POLICYDB_H_ 26 27 #include <linux/flex_array.h> 28 29 #include "symtab.h" 30 #include "avtab.h" 31 #include "sidtab.h" 32 #include "ebitmap.h" 33 #include "mls_types.h" 34 #include "context.h" 35 #include "constraint.h" 36 37 /* 38 * A datum type is defined for each kind of symbol 39 * in the configuration data: individual permissions, 40 * common prefixes for access vectors, classes, 41 * users, roles, types, sensitivities, categories, etc. 42 */ 43 44 /* Permission attributes */ 45 struct perm_datum { 46 u32 value; /* permission bit + 1 */ 47 }; 48 49 /* Attributes of a common prefix for access vectors */ 50 struct common_datum { 51 u32 value; /* internal common value */ 52 struct symtab permissions; /* common permissions */ 53 }; 54 55 /* Class attributes */ 56 struct class_datum { 57 u32 value; /* class value */ 58 char *comkey; /* common name */ 59 struct common_datum *comdatum; /* common datum */ 60 struct symtab permissions; /* class-specific permission symbol table */ 61 struct constraint_node *constraints; /* constraints on class permissions */ 62 struct constraint_node *validatetrans; /* special transition rules */ 63 /* Options how a new object user, role, and type should be decided */ 64 #define DEFAULT_SOURCE 1 65 #define DEFAULT_TARGET 2 66 char default_user; 67 char default_role; 68 char default_type; 69 /* Options how a new object range should be decided */ 70 #define DEFAULT_SOURCE_LOW 1 71 #define DEFAULT_SOURCE_HIGH 2 72 #define DEFAULT_SOURCE_LOW_HIGH 3 73 #define DEFAULT_TARGET_LOW 4 74 #define DEFAULT_TARGET_HIGH 5 75 #define DEFAULT_TARGET_LOW_HIGH 6 76 char default_range; 77 }; 78 79 /* Role attributes */ 80 struct role_datum { 81 u32 value; /* internal role value */ 82 u32 bounds; /* boundary of role */ 83 struct ebitmap dominates; /* set of roles dominated by this role */ 84 struct ebitmap types; /* set of authorized types for role */ 85 }; 86 87 struct role_trans { 88 u32 role; /* current role */ 89 u32 type; /* program executable type, or new object type */ 90 u32 tclass; /* process class, or new object class */ 91 u32 new_role; /* new role */ 92 struct role_trans *next; 93 }; 94 95 struct filename_trans { 96 u32 stype; /* current process */ 97 u32 ttype; /* parent dir context */ 98 u16 tclass; /* class of new object */ 99 const char *name; /* last path component */ 100 }; 101 102 struct filename_trans_datum { 103 u32 otype; /* expected of new object */ 104 }; 105 106 struct role_allow { 107 u32 role; /* current role */ 108 u32 new_role; /* new role */ 109 struct role_allow *next; 110 }; 111 112 /* Type attributes */ 113 struct type_datum { 114 u32 value; /* internal type value */ 115 u32 bounds; /* boundary of type */ 116 unsigned char primary; /* primary name? */ 117 unsigned char attribute;/* attribute ?*/ 118 }; 119 120 /* User attributes */ 121 struct user_datum { 122 u32 value; /* internal user value */ 123 u32 bounds; /* bounds of user */ 124 struct ebitmap roles; /* set of authorized roles for user */ 125 struct mls_range range; /* MLS range (min - max) for user */ 126 struct mls_level dfltlevel; /* default login MLS level for user */ 127 }; 128 129 130 /* Sensitivity attributes */ 131 struct level_datum { 132 struct mls_level *level; /* sensitivity and associated categories */ 133 unsigned char isalias; /* is this sensitivity an alias for another? */ 134 }; 135 136 /* Category attributes */ 137 struct cat_datum { 138 u32 value; /* internal category bit + 1 */ 139 unsigned char isalias; /* is this category an alias for another? */ 140 }; 141 142 struct range_trans { 143 u32 source_type; 144 u32 target_type; 145 u32 target_class; 146 }; 147 148 /* Boolean data type */ 149 struct cond_bool_datum { 150 __u32 value; /* internal type value */ 151 int state; 152 }; 153 154 struct cond_node; 155 156 /* 157 * type set preserves data needed to determine constraint info from 158 * policy source. This is not used by the kernel policy but allows 159 * utilities such as audit2allow to determine constraint denials. 160 */ 161 struct type_set { 162 struct ebitmap types; 163 struct ebitmap negset; 164 u32 flags; 165 }; 166 167 /* 168 * The configuration data includes security contexts for 169 * initial SIDs, unlabeled file systems, TCP and UDP port numbers, 170 * network interfaces, and nodes. This structure stores the 171 * relevant data for one such entry. Entries of the same kind 172 * (e.g. all initial SIDs) are linked together into a list. 173 */ 174 struct ocontext { 175 union { 176 char *name; /* name of initial SID, fs, netif, fstype, path */ 177 struct { 178 u8 protocol; 179 u16 low_port; 180 u16 high_port; 181 } port; /* TCP or UDP port information */ 182 struct { 183 u32 addr; 184 u32 mask; 185 } node; /* node information */ 186 struct { 187 u32 addr[4]; 188 u32 mask[4]; 189 } node6; /* IPv6 node information */ 190 } u; 191 union { 192 u32 sclass; /* security class for genfs */ 193 u32 behavior; /* labeling behavior for fs_use */ 194 } v; 195 struct context context[2]; /* security context(s) */ 196 u32 sid[2]; /* SID(s) */ 197 struct ocontext *next; 198 }; 199 200 struct genfs { 201 char *fstype; 202 struct ocontext *head; 203 struct genfs *next; 204 }; 205 206 /* symbol table array indices */ 207 #define SYM_COMMONS 0 208 #define SYM_CLASSES 1 209 #define SYM_ROLES 2 210 #define SYM_TYPES 3 211 #define SYM_USERS 4 212 #define SYM_BOOLS 5 213 #define SYM_LEVELS 6 214 #define SYM_CATS 7 215 #define SYM_NUM 8 216 217 /* object context array indices */ 218 #define OCON_ISID 0 /* initial SIDs */ 219 #define OCON_FS 1 /* unlabeled file systems */ 220 #define OCON_PORT 2 /* TCP and UDP port numbers */ 221 #define OCON_NETIF 3 /* network interfaces */ 222 #define OCON_NODE 4 /* nodes */ 223 #define OCON_FSUSE 5 /* fs_use */ 224 #define OCON_NODE6 6 /* IPv6 nodes */ 225 #define OCON_NUM 7 226 227 /* The policy database */ 228 struct policydb { 229 int mls_enabled; 230 231 /* symbol tables */ 232 struct symtab symtab[SYM_NUM]; 233 #define p_commons symtab[SYM_COMMONS] 234 #define p_classes symtab[SYM_CLASSES] 235 #define p_roles symtab[SYM_ROLES] 236 #define p_types symtab[SYM_TYPES] 237 #define p_users symtab[SYM_USERS] 238 #define p_bools symtab[SYM_BOOLS] 239 #define p_levels symtab[SYM_LEVELS] 240 #define p_cats symtab[SYM_CATS] 241 242 /* symbol names indexed by (value - 1) */ 243 struct flex_array *sym_val_to_name[SYM_NUM]; 244 245 /* class, role, and user attributes indexed by (value - 1) */ 246 struct class_datum **class_val_to_struct; 247 struct role_datum **role_val_to_struct; 248 struct user_datum **user_val_to_struct; 249 struct flex_array *type_val_to_struct_array; 250 251 /* type enforcement access vectors and transitions */ 252 struct avtab te_avtab; 253 254 /* role transitions */ 255 struct role_trans *role_tr; 256 257 /* file transitions with the last path component */ 258 /* quickly exclude lookups when parent ttype has no rules */ 259 struct ebitmap filename_trans_ttypes; 260 /* actual set of filename_trans rules */ 261 struct hashtab *filename_trans; 262 263 /* bools indexed by (value - 1) */ 264 struct cond_bool_datum **bool_val_to_struct; 265 /* type enforcement conditional access vectors and transitions */ 266 struct avtab te_cond_avtab; 267 /* linked list indexing te_cond_avtab by conditional */ 268 struct cond_node *cond_list; 269 270 /* role allows */ 271 struct role_allow *role_allow; 272 273 /* security contexts of initial SIDs, unlabeled file systems, 274 TCP or UDP port numbers, network interfaces and nodes */ 275 struct ocontext *ocontexts[OCON_NUM]; 276 277 /* security contexts for files in filesystems that cannot support 278 a persistent label mapping or use another 279 fixed labeling behavior. */ 280 struct genfs *genfs; 281 282 /* range transitions table (range_trans_key -> mls_range) */ 283 struct hashtab *range_tr; 284 285 /* type -> attribute reverse mapping */ 286 struct flex_array *type_attr_map_array; 287 288 struct ebitmap policycaps; 289 290 struct ebitmap permissive_map; 291 292 /* length of this policy when it was loaded */ 293 size_t len; 294 295 unsigned int policyvers; 296 297 unsigned int reject_unknown : 1; 298 unsigned int allow_unknown : 1; 299 300 u16 process_class; 301 u32 process_trans_perms; 302 }; 303 304 extern void policydb_destroy(struct policydb *p); 305 extern int policydb_load_isids(struct policydb *p, struct sidtab *s); 306 extern int policydb_context_isvalid(struct policydb *p, struct context *c); 307 extern int policydb_class_isvalid(struct policydb *p, unsigned int class); 308 extern int policydb_type_isvalid(struct policydb *p, unsigned int type); 309 extern int policydb_role_isvalid(struct policydb *p, unsigned int role); 310 extern int policydb_read(struct policydb *p, void *fp); 311 extern int policydb_write(struct policydb *p, void *fp); 312 313 #define PERM_SYMTAB_SIZE 32 314 315 #define POLICYDB_CONFIG_MLS 1 316 317 /* the config flags related to unknown classes/perms are bits 2 and 3 */ 318 #define REJECT_UNKNOWN 0x00000002 319 #define ALLOW_UNKNOWN 0x00000004 320 321 #define OBJECT_R "object_r" 322 #define OBJECT_R_VAL 1 323 324 #define POLICYDB_MAGIC SELINUX_MAGIC 325 #define POLICYDB_STRING "SE Linux" 326 327 struct policy_file { 328 char *data; 329 size_t len; 330 }; 331 332 struct policy_data { 333 struct policydb *p; 334 void *fp; 335 }; 336 337 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes) 338 { 339 if (bytes > fp->len) 340 return -EINVAL; 341 342 memcpy(buf, fp->data, bytes); 343 fp->data += bytes; 344 fp->len -= bytes; 345 return 0; 346 } 347 348 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp) 349 { 350 size_t len = bytes * num; 351 352 memcpy(fp->data, buf, len); 353 fp->data += len; 354 fp->len -= len; 355 356 return 0; 357 } 358 359 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr) 360 { 361 struct flex_array *fa = p->sym_val_to_name[sym_num]; 362 363 return flex_array_get_ptr(fa, element_nr); 364 } 365 366 extern u16 string_to_security_class(struct policydb *p, const char *name); 367 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name); 368 369 #endif /* _SS_POLICYDB_H_ */ 370 371