security/selinux/ss/policydb.h

   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 "symtab.h"
  28 #include "avtab.h"
  29 #include "sidtab.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 };
  60
  61 /* Role attributes */
  62 struct role_datum {
  63         u32 value;                      /* internal role value */
  64         struct ebitmap dominates;       /* set of roles dominated by this role */
  65         struct ebitmap types;           /* set of authorized types for role */
  66 };
  67
  68 struct role_trans {
  69         u32 role;               /* current role */
  70         u32 type;               /* program executable type */
  71         u32 new_role;           /* new role */
  72         struct role_trans *next;
  73 };
  74
  75 struct role_allow {
  76         u32 role;               /* current role */
  77         u32 new_role;           /* new role */
  78         struct role_allow *next;
  79 };
  80
  81 /* Type attributes */
  82 struct type_datum {
  83         u32 value;              /* internal type value */
  84         unsigned char primary;  /* primary name? */
  85 };
  86
  87 /* User attributes */
  88 struct user_datum {
  89         u32 value;                      /* internal user value */
  90         struct ebitmap roles;           /* set of authorized roles for user */
  91         struct mls_range range;         /* MLS range (min - max) for user */
  92         struct mls_level dfltlevel;     /* default login MLS level for user */
  93 };
  94
  95
  96 /* Sensitivity attributes */
  97 struct level_datum {
  98         struct mls_level *level;        /* sensitivity and associated categories */
  99         unsigned char isalias;  /* is this sensitivity an alias for another? */
 100 };
 101
 102 /* Category attributes */
 103 struct cat_datum {
 104         u32 value;              /* internal category bit + 1 */
 105         unsigned char isalias;  /* is this category an alias for another? */
 106 };
 107
 108 struct range_trans {
 109         u32 source_type;
 110         u32 target_type;
 111         u32 target_class;
 112         struct mls_range target_range;
 113         struct range_trans *next;
 114 };
 115
 116 /* Boolean data type */
 117 struct cond_bool_datum {
 118         __u32 value;            /* internal type value */
 119         int state;
 120 };
 121
 122 struct cond_node;
 123
 124 /*
 125  * The configuration data includes security contexts for
 126  * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
 127  * network interfaces, and nodes.  This structure stores the
 128  * relevant data for one such entry.  Entries of the same kind
 129  * (e.g. all initial SIDs) are linked together into a list.
 130  */
 131 struct ocontext {
 132         union {
 133                 char *name;     /* name of initial SID, fs, netif, fstype, path */
 134                 struct {
 135                         u8 protocol;
 136                         u16 low_port;
 137                         u16 high_port;
 138                 } port;         /* TCP or UDP port information */
 139                 struct {
 140                         u32 addr;
 141                         u32 mask;
 142                 } node;         /* node information */
 143                 struct {
 144                         u32 addr[4];
 145                         u32 mask[4];
 146                 } node6;        /* IPv6 node information */
 147         } u;
 148         union {
 149                 u32 sclass;  /* security class for genfs */
 150                 u32 behavior;  /* labeling behavior for fs_use */
 151         } v;
 152         struct context context[2];      /* security context(s) */
 153         u32 sid[2];     /* SID(s) */
 154         struct ocontext *next;
 155 };
 156
 157 struct genfs {
 158         char *fstype;
 159         struct ocontext *head;
 160         struct genfs *next;
 161 };
 162
 163 /* symbol table array indices */
 164 #define SYM_COMMONS 0
 165 #define SYM_CLASSES 1
 166 #define SYM_ROLES   2
 167 #define SYM_TYPES   3
 168 #define SYM_USERS   4
 169 #define SYM_BOOLS   5
 170 #define SYM_LEVELS  6
 171 #define SYM_CATS    7
 172 #define SYM_NUM     8
 173
 174 /* object context array indices */
 175 #define OCON_ISID  0    /* initial SIDs */
 176 #define OCON_FS    1    /* unlabeled file systems */
 177 #define OCON_PORT  2    /* TCP and UDP port numbers */
 178 #define OCON_NETIF 3    /* network interfaces */
 179 #define OCON_NODE  4    /* nodes */
 180 #define OCON_FSUSE 5    /* fs_use */
 181 #define OCON_NODE6 6    /* IPv6 nodes */
 182 #define OCON_NUM   7
 183
 184 /* The policy database */
 185 struct policydb {
 186         /* symbol tables */
 187         struct symtab symtab[SYM_NUM];
 188 #define p_commons symtab[SYM_COMMONS]
 189 #define p_classes symtab[SYM_CLASSES]
 190 #define p_roles symtab[SYM_ROLES]
 191 #define p_types symtab[SYM_TYPES]
 192 #define p_users symtab[SYM_USERS]
 193 #define p_bools symtab[SYM_BOOLS]
 194 #define p_levels symtab[SYM_LEVELS]
 195 #define p_cats symtab[SYM_CATS]
 196
 197         /* symbol names indexed by (value - 1) */
 198         char **sym_val_to_name[SYM_NUM];
 199 #define p_common_val_to_name sym_val_to_name[SYM_COMMONS]
 200 #define p_class_val_to_name sym_val_to_name[SYM_CLASSES]
 201 #define p_role_val_to_name sym_val_to_name[SYM_ROLES]
 202 #define p_type_val_to_name sym_val_to_name[SYM_TYPES]
 203 #define p_user_val_to_name sym_val_to_name[SYM_USERS]
 204 #define p_bool_val_to_name sym_val_to_name[SYM_BOOLS]
 205 #define p_sens_val_to_name sym_val_to_name[SYM_LEVELS]
 206 #define p_cat_val_to_name sym_val_to_name[SYM_CATS]
 207
 208         /* class, role, and user attributes indexed by (value - 1) */
 209         struct class_datum **class_val_to_struct;
 210         struct role_datum **role_val_to_struct;
 211         struct user_datum **user_val_to_struct;
 212
 213         /* type enforcement access vectors and transitions */
 214         struct avtab te_avtab;
 215
 216         /* role transitions */
 217         struct role_trans *role_tr;
 218
 219         /* bools indexed by (value - 1) */
 220         struct cond_bool_datum **bool_val_to_struct;
 221         /* type enforcement conditional access vectors and transitions */
 222         struct avtab te_cond_avtab;
 223         /* linked list indexing te_cond_avtab by conditional */
 224         struct cond_node* cond_list;
 225
 226         /* role allows */
 227         struct role_allow *role_allow;
 228
 229         /* security contexts of initial SIDs, unlabeled file systems,
 230            TCP or UDP port numbers, network interfaces and nodes */
 231         struct ocontext *ocontexts[OCON_NUM];
 232
 233         /* security contexts for files in filesystems that cannot support
 234            a persistent label mapping or use another
 235            fixed labeling behavior. */
 236         struct genfs *genfs;
 237
 238         /* range transitions */
 239         struct range_trans *range_tr;
 240
 241         /* type -> attribute reverse mapping */
 242         struct ebitmap *type_attr_map;
 243
 244         struct ebitmap policycaps;
 245
 246         unsigned int policyvers;
 247
 248         unsigned int reject_unknown : 1;
 249         unsigned int allow_unknown : 1;
 250         u32 *undefined_perms;
 251 };
 252
 253 extern void policydb_destroy(struct policydb *p);
 254 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
 255 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
 256 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
 257 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
 258 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
 259 extern int policydb_read(struct policydb *p, void *fp);
 260
 261 #define PERM_SYMTAB_SIZE 32
 262
 263 #define POLICYDB_CONFIG_MLS    1
 264
 265 /* the config flags related to unknown classes/perms are bits 2 and 3 */
 266 #define REJECT_UNKNOWN  0x00000002
 267 #define ALLOW_UNKNOWN   0x00000004
 268
 269 #define OBJECT_R "object_r"
 270 #define OBJECT_R_VAL 1
 271
 272 #define POLICYDB_MAGIC SELINUX_MAGIC
 273 #define POLICYDB_STRING "SE Linux"
 274
 275 struct policy_file {
 276         char *data;
 277         size_t len;
 278 };
 279
 280 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
 281 {
 282         if (bytes > fp->len)
 283                 return -EINVAL;
 284
 285         memcpy(buf, fp->data, bytes);
 286         fp->data += bytes;
 287         fp->len -= bytes;
 288         return 0;
 289 }
 290
 291 #endif  /* _SS_POLICYDB_H_ */
 292