security/selinux/ss/policydb.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * A policy database (policydb) specifies the
   4  * configuration data for the security policy.
   5  *
   6  * Author : Stephen Smalley, <sds@tycho.nsa.gov>
   7  */
   8
   9 /*
  10  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
  11  *
  12  *      Support for enhanced MLS infrastructure.
  13  *
  14  * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
  15  *
  16  *      Added conditional policy language extensions
  17  *
  18  * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  19  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  20  */
  21
  22 #ifndef _SS_POLICYDB_H_
  23 #define _SS_POLICYDB_H_
  24
  25 #include "symtab.h"
  26 #include "avtab.h"
  27 #include "sidtab.h"
  28 #include "ebitmap.h"
  29 #include "mls_types.h"
  30 #include "context.h"
  31 #include "constraint.h"
  32
  33 /*
  34  * A datum type is defined for each kind of symbol
  35  * in the configuration data:  individual permissions,
  36  * common prefixes for access vectors, classes,
  37  * users, roles, types, sensitivities, categories, etc.
  38  */
  39
  40 /* Permission attributes */
  41 struct perm_datum {
  42         u32 value;              /* permission bit + 1 */
  43 };
  44
  45 /* Attributes of a common prefix for access vectors */
  46 struct common_datum {
  47         u32 value;                      /* internal common value */
  48         struct symtab permissions;      /* common permissions */
  49 };
  50
  51 /* Class attributes */
  52 struct class_datum {
  53         u32 value;                      /* class value */
  54         char *comkey;                   /* common name */
  55         struct common_datum *comdatum;  /* common datum */
  56         struct symtab permissions;      /* class-specific permission symbol table */
  57         struct constraint_node *constraints;    /* constraints on class permissions */
  58         struct constraint_node *validatetrans;  /* special transition rules */
  59 /* Options how a new object user, role, and type should be decided */
  60 #define DEFAULT_SOURCE         1
  61 #define DEFAULT_TARGET         2
  62         char default_user;
  63         char default_role;
  64         char default_type;
  65 /* Options how a new object range should be decided */
  66 #define DEFAULT_SOURCE_LOW     1
  67 #define DEFAULT_SOURCE_HIGH    2
  68 #define DEFAULT_SOURCE_LOW_HIGH        3
  69 #define DEFAULT_TARGET_LOW     4
  70 #define DEFAULT_TARGET_HIGH    5
  71 #define DEFAULT_TARGET_LOW_HIGH        6
  72 #define DEFAULT_GLBLUB          7
  73         char default_range;
  74 };
  75
  76 /* Role attributes */
  77 struct role_datum {
  78         u32 value;                      /* internal role value */
  79         u32 bounds;                     /* boundary of role */
  80         struct ebitmap dominates;       /* set of roles dominated by this role */
  81         struct ebitmap types;           /* set of authorized types for role */
  82 };
  83
  84 struct role_trans {
  85         u32 role;               /* current role */
  86         u32 type;               /* program executable type, or new object type */
  87         u32 tclass;             /* process class, or new object class */
  88         u32 new_role;           /* new role */
  89         struct role_trans *next;
  90 };
  91
  92 struct filename_trans_key {
  93         u32 ttype;              /* parent dir context */
  94         u16 tclass;             /* class of new object */
  95         const char *name;       /* last path component */
  96 };
  97
  98 struct filename_trans_datum {
  99         struct ebitmap stypes;  /* bitmap of source types for this otype */
 100         u32 otype;              /* resulting type of new object */
 101         struct filename_trans_datum *next;      /* record for next otype*/
 102 };
 103
 104 struct role_allow {
 105         u32 role;               /* current role */
 106         u32 new_role;           /* new role */
 107         struct role_allow *next;
 108 };
 109
 110 /* Type attributes */
 111 struct type_datum {
 112         u32 value;              /* internal type value */
 113         u32 bounds;             /* boundary of type */
 114         unsigned char primary;  /* primary name? */
 115         unsigned char attribute;/* attribute ?*/
 116 };
 117
 118 /* User attributes */
 119 struct user_datum {
 120         u32 value;                      /* internal user value */
 121         u32 bounds;                     /* bounds of user */
 122         struct ebitmap roles;           /* set of authorized roles for user */
 123         struct mls_range range;         /* MLS range (min - max) for user */
 124         struct mls_level dfltlevel;     /* default login MLS level for user */
 125 };
 126
 127
 128 /* Sensitivity attributes */
 129 struct level_datum {
 130         struct mls_level *level;        /* sensitivity and associated categories */
 131         unsigned char isalias;  /* is this sensitivity an alias for another? */
 132 };
 133
 134 /* Category attributes */
 135 struct cat_datum {
 136         u32 value;              /* internal category bit + 1 */
 137         unsigned char isalias;  /* is this category an alias for another? */
 138 };
 139
 140 struct range_trans {
 141         u32 source_type;
 142         u32 target_type;
 143         u32 target_class;
 144 };
 145
 146 /* Boolean data type */
 147 struct cond_bool_datum {
 148         __u32 value;            /* internal type value */
 149         int state;
 150 };
 151
 152 struct cond_node;
 153
 154 /*
 155  * type set preserves data needed to determine constraint info from
 156  * policy source. This is not used by the kernel policy but allows
 157  * utilities such as audit2allow to determine constraint denials.
 158  */
 159 struct type_set {
 160         struct ebitmap types;
 161         struct ebitmap negset;
 162         u32 flags;
 163 };
 164
 165 /*
 166  * The configuration data includes security contexts for
 167  * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
 168  * network interfaces, and nodes.  This structure stores the
 169  * relevant data for one such entry.  Entries of the same kind
 170  * (e.g. all initial SIDs) are linked together into a list.
 171  */
 172 struct ocontext {
 173         union {
 174                 char *name;     /* name of initial SID, fs, netif, fstype, path */
 175                 struct {
 176                         u8 protocol;
 177                         u16 low_port;
 178                         u16 high_port;
 179                 } port;         /* TCP or UDP port information */
 180                 struct {
 181                         u32 addr;
 182                         u32 mask;
 183                 } node;         /* node information */
 184                 struct {
 185                         u32 addr[4];
 186                         u32 mask[4];
 187                 } node6;        /* IPv6 node information */
 188                 struct {
 189                         u64 subnet_prefix;
 190                         u16 low_pkey;
 191                         u16 high_pkey;
 192                 } ibpkey;
 193                 struct {
 194                         char *dev_name;
 195                         u8 port;
 196                 } ibendport;
 197         } u;
 198         union {
 199                 u32 sclass;  /* security class for genfs */
 200                 u32 behavior;  /* labeling behavior for fs_use */
 201         } v;
 202         struct context context[2];      /* security context(s) */
 203         u32 sid[2];     /* SID(s) */
 204         struct ocontext *next;
 205 };
 206
 207 struct genfs {
 208         char *fstype;
 209         struct ocontext *head;
 210         struct genfs *next;
 211 };
 212
 213 /* symbol table array indices */
 214 #define SYM_COMMONS 0
 215 #define SYM_CLASSES 1
 216 #define SYM_ROLES   2
 217 #define SYM_TYPES   3
 218 #define SYM_USERS   4
 219 #define SYM_BOOLS   5
 220 #define SYM_LEVELS  6
 221 #define SYM_CATS    7
 222 #define SYM_NUM     8
 223
 224 /* object context array indices */
 225 #define OCON_ISID       0 /* initial SIDs */
 226 #define OCON_FS         1 /* unlabeled file systems */
 227 #define OCON_PORT       2 /* TCP and UDP port numbers */
 228 #define OCON_NETIF      3 /* network interfaces */
 229 #define OCON_NODE       4 /* nodes */
 230 #define OCON_FSUSE      5 /* fs_use */
 231 #define OCON_NODE6      6 /* IPv6 nodes */
 232 #define OCON_IBPKEY     7 /* Infiniband PKeys */
 233 #define OCON_IBENDPORT  8 /* Infiniband end ports */
 234 #define OCON_NUM        9
 235
 236 /* The policy database */
 237 struct policydb {
 238         int mls_enabled;
 239
 240         /* symbol tables */
 241         struct symtab symtab[SYM_NUM];
 242 #define p_commons symtab[SYM_COMMONS]
 243 #define p_classes symtab[SYM_CLASSES]
 244 #define p_roles symtab[SYM_ROLES]
 245 #define p_types symtab[SYM_TYPES]
 246 #define p_users symtab[SYM_USERS]
 247 #define p_bools symtab[SYM_BOOLS]
 248 #define p_levels symtab[SYM_LEVELS]
 249 #define p_cats symtab[SYM_CATS]
 250
 251         /* symbol names indexed by (value - 1) */
 252         char            **sym_val_to_name[SYM_NUM];
 253
 254         /* class, role, and user attributes indexed by (value - 1) */
 255         struct class_datum **class_val_to_struct;
 256         struct role_datum **role_val_to_struct;
 257         struct user_datum **user_val_to_struct;
 258         struct type_datum **type_val_to_struct;
 259
 260         /* type enforcement access vectors and transitions */
 261         struct avtab te_avtab;
 262
 263         /* role transitions */
 264         struct role_trans *role_tr;
 265
 266         /* file transitions with the last path component */
 267         /* quickly exclude lookups when parent ttype has no rules */
 268         struct ebitmap filename_trans_ttypes;
 269         /* actual set of filename_trans rules */
 270         struct hashtab *filename_trans;
 271         u32 filename_trans_count;
 272
 273         /* bools indexed by (value - 1) */
 274         struct cond_bool_datum **bool_val_to_struct;
 275         /* type enforcement conditional access vectors and transitions */
 276         struct avtab te_cond_avtab;
 277         /* array indexing te_cond_avtab by conditional */
 278         struct cond_node *cond_list;
 279         u32 cond_list_len;
 280
 281         /* role allows */
 282         struct role_allow *role_allow;
 283
 284         /* security contexts of initial SIDs, unlabeled file systems,
 285            TCP or UDP port numbers, network interfaces and nodes */
 286         struct ocontext *ocontexts[OCON_NUM];
 287
 288         /* security contexts for files in filesystems that cannot support
 289            a persistent label mapping or use another
 290            fixed labeling behavior. */
 291         struct genfs *genfs;
 292
 293         /* range transitions table (range_trans_key -> mls_range) */
 294         struct hashtab *range_tr;
 295
 296         /* type -> attribute reverse mapping */
 297         struct ebitmap *type_attr_map_array;
 298
 299         struct ebitmap policycaps;
 300
 301         struct ebitmap permissive_map;
 302
 303         /* length of this policy when it was loaded */
 304         size_t len;
 305
 306         unsigned int policyvers;
 307
 308         unsigned int reject_unknown : 1;
 309         unsigned int allow_unknown : 1;
 310
 311         u16 process_class;
 312         u32 process_trans_perms;
 313 } __randomize_layout;
 314
 315 extern void policydb_destroy(struct policydb *p);
 316 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
 317 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
 318 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
 319 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
 320 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
 321 extern int policydb_read(struct policydb *p, void *fp);
 322 extern int policydb_write(struct policydb *p, void *fp);
 323
 324 #define POLICYDB_CONFIG_MLS    1
 325
 326 /* the config flags related to unknown classes/perms are bits 2 and 3 */
 327 #define REJECT_UNKNOWN  0x00000002
 328 #define ALLOW_UNKNOWN   0x00000004
 329
 330 #define OBJECT_R "object_r"
 331 #define OBJECT_R_VAL 1
 332
 333 #define POLICYDB_MAGIC SELINUX_MAGIC
 334 #define POLICYDB_STRING "SE Linux"
 335
 336 struct policy_file {
 337         char *data;
 338         size_t len;
 339 };
 340
 341 struct policy_data {
 342         struct policydb *p;
 343         void *fp;
 344 };
 345
 346 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
 347 {
 348         if (bytes > fp->len)
 349                 return -EINVAL;
 350
 351         memcpy(buf, fp->data, bytes);
 352         fp->data += bytes;
 353         fp->len -= bytes;
 354         return 0;
 355 }
 356
 357 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
 358 {
 359         size_t len = bytes * num;
 360
 361         memcpy(fp->data, buf, len);
 362         fp->data += len;
 363         fp->len -= len;
 364
 365         return 0;
 366 }
 367
 368 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
 369 {
 370         return p->sym_val_to_name[sym_num][element_nr];
 371 }
 372
 373 extern u16 string_to_security_class(struct policydb *p, const char *name);
 374 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
 375
 376 #endif  /* _SS_POLICYDB_H_ */
 377