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@tycho.nsa.gov> 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 #include <linux/flex_array.h> 28 29 struct avtab_key { 30 u16 source_type; /* source type */ 31 u16 target_type; /* target type */ 32 u16 target_class; /* target object class */ 33 #define AVTAB_ALLOWED 0x0001 34 #define AVTAB_AUDITALLOW 0x0002 35 #define AVTAB_AUDITDENY 0x0004 36 #define AVTAB_AV (AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY) 37 #define AVTAB_TRANSITION 0x0010 38 #define AVTAB_MEMBER 0x0020 39 #define AVTAB_CHANGE 0x0040 40 #define AVTAB_TYPE (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE) 41 /* extended permissions */ 42 #define AVTAB_XPERMS_ALLOWED 0x0100 43 #define AVTAB_XPERMS_AUDITALLOW 0x0200 44 #define AVTAB_XPERMS_DONTAUDIT 0x0400 45 #define AVTAB_XPERMS (AVTAB_XPERMS_ALLOWED | \ 46 AVTAB_XPERMS_AUDITALLOW | \ 47 AVTAB_XPERMS_DONTAUDIT) 48 #define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */ 49 #define AVTAB_ENABLED 0x8000 /* reserved for used in cond_avtab */ 50 u16 specified; /* what field is specified */ 51 }; 52 53 /* 54 * For operations that require more than the 32 permissions provided by the avc 55 * extended permissions may be used to provide 256 bits of permissions. 56 */ 57 struct avtab_extended_perms { 58 /* These are not flags. All 256 values may be used */ 59 #define AVTAB_XPERMS_IOCTLFUNCTION 0x01 60 #define AVTAB_XPERMS_IOCTLDRIVER 0x02 61 /* extension of the avtab_key specified */ 62 u8 specified; /* ioctl, netfilter, ... */ 63 /* 64 * if 256 bits is not adequate as is often the case with ioctls, then 65 * multiple extended perms may be used and the driver field 66 * specifies which permissions are included. 67 */ 68 u8 driver; 69 /* 256 bits of permissions */ 70 struct extended_perms_data perms; 71 }; 72 73 struct avtab_datum { 74 union { 75 u32 data; /* access vector or type value */ 76 struct avtab_extended_perms *xperms; 77 } u; 78 }; 79 80 struct avtab_node { 81 struct avtab_key key; 82 struct avtab_datum datum; 83 struct avtab_node *next; 84 }; 85 86 struct avtab { 87 struct flex_array *htable; 88 u32 nel; /* number of elements */ 89 u32 nslot; /* number of hash slots */ 90 u32 mask; /* mask to compute hash func */ 91 92 }; 93 94 int avtab_init(struct avtab *); 95 int avtab_alloc(struct avtab *, u32); 96 struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *k); 97 void avtab_destroy(struct avtab *h); 98 void avtab_hash_eval(struct avtab *h, char *tag); 99 100 struct policydb; 101 int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, 102 int (*insert)(struct avtab *a, struct avtab_key *k, 103 struct avtab_datum *d, void *p), 104 void *p); 105 106 int avtab_read(struct avtab *a, void *fp, struct policydb *pol); 107 int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp); 108 int avtab_write(struct policydb *p, struct avtab *a, void *fp); 109 110 struct avtab_node *avtab_insert_nonunique(struct avtab *h, struct avtab_key *key, 111 struct avtab_datum *datum); 112 113 struct avtab_node *avtab_search_node(struct avtab *h, struct avtab_key *key); 114 115 struct avtab_node *avtab_search_node_next(struct avtab_node *node, int specified); 116 117 void avtab_cache_init(void); 118 void avtab_cache_destroy(void); 119 120 #define MAX_AVTAB_HASH_BITS 16 121 #define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS) 122 123 #endif /* _SS_AVTAB_H_ */ 124 125