1 /* 2 * An access vector table (avtab) is a hash table 3 * of access vectors and transition types indexed 4 * by a type pair and a class. An access vector 5 * table is used to represent the type enforcement 6 * tables. 7 * 8 * Author : Stephen Smalley, <sds@epoch.ncsc.mil> 9 */ 10 11 /* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> 12 * 13 * Added conditional policy language extensions 14 * 15 * Copyright (C) 2003 Tresys Technology, LLC 16 * This program is free software; you can redistribute it and/or modify 17 * it under the terms of the GNU General Public License as published by 18 * the Free Software Foundation, version 2. 19 * 20 * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp> 21 * Tuned number of hash slots for avtab to reduce memory usage 22 */ 23 #ifndef _SS_AVTAB_H_ 24 #define _SS_AVTAB_H_ 25 26 #include "security.h" 27 28 struct avtab_key { 29 u16 source_type; /* source type */ 30 u16 target_type; /* target type */ 31 u16 target_class; /* target object class */ 32 #define AVTAB_ALLOWED 0x0001 33 #define AVTAB_AUDITALLOW 0x0002 34 #define AVTAB_AUDITDENY 0x0004 35 #define AVTAB_AV (AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY) 36 #define AVTAB_TRANSITION 0x0010 37 #define AVTAB_MEMBER 0x0020 38 #define AVTAB_CHANGE 0x0040 39 #define AVTAB_TYPE (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE) 40 /* extended permissions */ 41 #define AVTAB_XPERMS_ALLOWED 0x0100 42 #define AVTAB_XPERMS_AUDITALLOW 0x0200 43 #define AVTAB_XPERMS_DONTAUDIT 0x0400 44 #define AVTAB_XPERMS (AVTAB_XPERMS_ALLOWED | \ 45 AVTAB_XPERMS_AUDITALLOW | \ 46 AVTAB_XPERMS_DONTAUDIT) 47 #define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */ 48 #define AVTAB_ENABLED 0x8000 /* reserved for used in cond_avtab */ 49 u16 specified; /* what field is specified */ 50 }; 51 52 /* 53 * For operations that require more than the 32 permissions provided by the avc 54 * extended permissions may be used to provide 256 bits of permissions. 55 */ 56 struct avtab_extended_perms { 57 /* These are not flags. All 256 values may be used */ 58 #define AVTAB_XPERMS_IOCTLFUNCTION 0x01 59 #define AVTAB_XPERMS_IOCTLDRIVER 0x02 60 /* extension of the avtab_key specified */ 61 u8 specified; /* ioctl, netfilter, ... */ 62 /* 63 * if 256 bits is not adequate as is often the case with ioctls, then 64 * multiple extended perms may be used and the driver field 65 * specifies which permissions are included. 66 */ 67 u8 driver; 68 /* 256 bits of permissions */ 69 struct extended_perms_data perms; 70 }; 71 72 struct avtab_datum { 73 union { 74 u32 data; /* access vector or type value */ 75 struct avtab_extended_perms *xperms; 76 } u; 77 }; 78 79 struct avtab_node { 80 struct avtab_key key; 81 struct avtab_datum datum; 82 struct avtab_node *next; 83 }; 84 85 struct avtab { 86 struct avtab_node **htable; 87 u32 nel; /* number of elements */ 88 u32 nslot; /* number of hash slots */ 89 u16 mask; /* mask to compute hash func */ 90 91 }; 92 93 int avtab_init(struct avtab *); 94 int avtab_alloc(struct avtab *, u32); 95 struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *k); 96 void avtab_destroy(struct avtab *h); 97 void avtab_hash_eval(struct avtab *h, char *tag); 98 99 struct policydb; 100 int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, 101 int (*insert)(struct avtab *a, struct avtab_key *k, 102 struct avtab_datum *d, void *p), 103 void *p); 104 105 int avtab_read(struct avtab *a, void *fp, struct policydb *pol); 106 int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp); 107 int avtab_write(struct policydb *p, struct avtab *a, void *fp); 108 109 struct avtab_node *avtab_insert_nonunique(struct avtab *h, struct avtab_key *key, 110 struct avtab_datum *datum); 111 112 struct avtab_node *avtab_search_node(struct avtab *h, struct avtab_key *key); 113 114 struct avtab_node *avtab_search_node_next(struct avtab_node *node, int specified); 115 116 void avtab_cache_init(void); 117 void avtab_cache_destroy(void); 118 119 #define MAX_AVTAB_HASH_BITS 11 120 #define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS) 121 122 #endif /* _SS_AVTAB_H_ */ 123 124