linux/security/selinux/ss/mls.h
Ondrej Mosnacek 5007728980 selinux: hash context structure directly
Always hashing the string representation is inefficient. Just hash the
contents of the structure directly (using jhash). If the context is
invalid (str & len are set), then hash the string as before, otherwise
hash the structured data.

Since the context hashing function is now faster (about 10 times), this
patch decreases the overhead of security_transition_sid(), which is
called from many hooks.

The jhash function seemed as a good choice, since it is used as the
default hashing algorithm in rhashtable.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Jeff Vander Stoep <jeffv@google.com>
Tested-by: Jeff Vander Stoep <jeffv@google.com>
[PM: fixed some spelling errors in the comments pointed out by JVS]
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-04-17 16:04:34 -04:00

117 lines
3.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Multi-level security (MLS) policy operations.
*
* Author : Stephen Smalley, <sds@tycho.nsa.gov>
*/
/*
* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
* Support for enhanced MLS infrastructure.
*
* Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
*/
/*
* Updated: Hewlett-Packard <paul@paul-moore.com>
*
* Added support to import/export the MLS label from NetLabel
*
* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
*/
#ifndef _SS_MLS_H_
#define _SS_MLS_H_
#include <linux/jhash.h>
#include "context.h"
#include "ebitmap.h"
#include "policydb.h"
int mls_compute_context_len(struct policydb *p, struct context *context);
void mls_sid_to_context(struct policydb *p, struct context *context,
char **scontext);
int mls_context_isvalid(struct policydb *p, struct context *c);
int mls_range_isvalid(struct policydb *p, struct mls_range *r);
int mls_level_isvalid(struct policydb *p, struct mls_level *l);
int mls_context_to_sid(struct policydb *p,
char oldc,
char *scontext,
struct context *context,
struct sidtab *s,
u32 def_sid);
int mls_from_string(struct policydb *p, char *str, struct context *context,
gfp_t gfp_mask);
int mls_range_set(struct context *context, struct mls_range *range);
int mls_convert_context(struct policydb *oldp,
struct policydb *newp,
struct context *oldc,
struct context *newc);
int mls_compute_sid(struct policydb *p,
struct context *scontext,
struct context *tcontext,
u16 tclass,
u32 specified,
struct context *newcontext,
bool sock);
int mls_setup_user_range(struct policydb *p,
struct context *fromcon, struct user_datum *user,
struct context *usercon);
#ifdef CONFIG_NETLABEL
void mls_export_netlbl_lvl(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr);
void mls_import_netlbl_lvl(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr);
int mls_export_netlbl_cat(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr);
int mls_import_netlbl_cat(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr);
#else
static inline void mls_export_netlbl_lvl(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr)
{
return;
}
static inline void mls_import_netlbl_lvl(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr)
{
return;
}
static inline int mls_export_netlbl_cat(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr)
{
return -ENOMEM;
}
static inline int mls_import_netlbl_cat(struct policydb *p,
struct context *context,
struct netlbl_lsm_secattr *secattr)
{
return -ENOMEM;
}
#endif
static inline u32 mls_range_hash(const struct mls_range *r, u32 hash)
{
hash = jhash_2words(r->level[0].sens, r->level[1].sens, hash);
hash = ebitmap_hash(&r->level[0].cat, hash);
hash = ebitmap_hash(&r->level[1].cat, hash);
return hash;
}
#endif /* _SS_MLS_H */