linux-sg2042/security/selinux/ss/avtab.h

122 lines
3.8 KiB
C

/*
* An access vector table (avtab) is a hash table
* of access vectors and transition types indexed
* by a type pair and a class. An access vector
* table is used to represent the type enforcement
* tables.
*
* Author : Stephen Smalley, <sds@tycho.nsa.gov>
*/
/* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Copyright (C) 2003 Tresys Technology, LLC
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*
* Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
* Tuned number of hash slots for avtab to reduce memory usage
*/
#ifndef _SS_AVTAB_H_
#define _SS_AVTAB_H_
#include "security.h"
#include <linux/flex_array.h>
struct avtab_key {
u16 source_type; /* source type */
u16 target_type; /* target type */
u16 target_class; /* target object class */
#define AVTAB_ALLOWED 0x0001
#define AVTAB_AUDITALLOW 0x0002
#define AVTAB_AUDITDENY 0x0004
#define AVTAB_AV (AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY)
#define AVTAB_TRANSITION 0x0010
#define AVTAB_MEMBER 0x0020
#define AVTAB_CHANGE 0x0040
#define AVTAB_TYPE (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE)
/* extended permissions */
#define AVTAB_XPERMS_ALLOWED 0x0100
#define AVTAB_XPERMS_AUDITALLOW 0x0200
#define AVTAB_XPERMS_DONTAUDIT 0x0400
#define AVTAB_XPERMS (AVTAB_XPERMS_ALLOWED | \
AVTAB_XPERMS_AUDITALLOW | \
AVTAB_XPERMS_DONTAUDIT)
#define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */
#define AVTAB_ENABLED 0x8000 /* reserved for used in cond_avtab */
u16 specified; /* what field is specified */
};
/*
* For operations that require more than the 32 permissions provided by the avc
* extended permissions may be used to provide 256 bits of permissions.
*/
struct avtab_extended_perms {
/* These are not flags. All 256 values may be used */
#define AVTAB_XPERMS_IOCTLFUNCTION 0x01
#define AVTAB_XPERMS_IOCTLDRIVER 0x02
/* extension of the avtab_key specified */
u8 specified; /* ioctl, netfilter, ... */
/*
* if 256 bits is not adequate as is often the case with ioctls, then
* multiple extended perms may be used and the driver field
* specifies which permissions are included.
*/
u8 driver;
/* 256 bits of permissions */
struct extended_perms_data perms;
};
struct avtab_datum {
union {
u32 data; /* access vector or type value */
struct avtab_extended_perms *xperms;
} u;
};
struct avtab_node {
struct avtab_key key;
struct avtab_datum datum;
struct avtab_node *next;
};
struct avtab {
struct flex_array *htable;
u32 nel; /* number of elements */
u32 nslot; /* number of hash slots */
u32 mask; /* mask to compute hash func */
};
int avtab_init(struct avtab *);
int avtab_alloc(struct avtab *, u32);
struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *k);
void avtab_destroy(struct avtab *h);
void avtab_hash_eval(struct avtab *h, char *tag);
struct policydb;
int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
int (*insert)(struct avtab *a, struct avtab_key *k,
struct avtab_datum *d, void *p),
void *p);
int avtab_read(struct avtab *a, void *fp, struct policydb *pol);
int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp);
int avtab_write(struct policydb *p, struct avtab *a, void *fp);
struct avtab_node *avtab_insert_nonunique(struct avtab *h, struct avtab_key *key,
struct avtab_datum *datum);
struct avtab_node *avtab_search_node(struct avtab *h, struct avtab_key *key);
struct avtab_node *avtab_search_node_next(struct avtab_node *node, int specified);
#define MAX_AVTAB_HASH_BITS 16
#define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
#endif /* _SS_AVTAB_H_ */