linux/linux-5.18.11/security/selinux/ss/context.c

33 lines
862 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Implementations of the security context functions.
*
* Author: Ondrej Mosnacek <omosnacek@gmail.com>
* Copyright (C) 2020 Red Hat, Inc.
*/
#include <linux/jhash.h>
#include "context.h"
#include "mls.h"
u32 context_compute_hash(const struct context *c)
{
u32 hash = 0;
/*
* If a context is invalid, it will always be represented by a
* context struct with only the len & str set (and vice versa)
* under a given policy. Since context structs from different
* policies should never meet, it is safe to hash valid and
* invalid contexts differently. The context_cmp() function
* already operates under the same assumption.
*/
if (c->len)
return full_name_hash(NULL, c->str, c->len);
hash = jhash_3words(c->user, c->role, c->type, hash);
hash = mls_range_hash(&c->range, hash);
return hash;
}