2 * Copyright (C) 2008 IBM Corporation
5 * Mimi Zohar <zohar@us.ibm.com>
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as
9 * published by the Free Software Foundation, version 2 of the
12 * File: integrity_iint.c
13 * - implements the integrity hooks: integrity_inode_alloc,
14 * integrity_inode_free
15 * - cache integrity information associated with an inode
16 * using a rbtree tree.
18 #include <linux/slab.h>
19 #include <linux/module.h>
20 #include <linux/spinlock.h>
21 #include <linux/rbtree.h>
22 #include "integrity.h"
24 static struct rb_root integrity_iint_tree
= RB_ROOT
;
25 static DEFINE_RWLOCK(integrity_iint_lock
);
26 static struct kmem_cache
*iint_cache __read_mostly
;
31 * __integrity_iint_find - return the iint associated with an inode
33 static struct integrity_iint_cache
*__integrity_iint_find(struct inode
*inode
)
35 struct integrity_iint_cache
*iint
;
36 struct rb_node
*n
= integrity_iint_tree
.rb_node
;
39 iint
= rb_entry(n
, struct integrity_iint_cache
, rb_node
);
41 if (inode
< iint
->inode
)
43 else if (inode
> iint
->inode
)
55 * integrity_iint_find - return the iint associated with an inode
57 struct integrity_iint_cache
*integrity_iint_find(struct inode
*inode
)
59 struct integrity_iint_cache
*iint
;
64 read_lock(&integrity_iint_lock
);
65 iint
= __integrity_iint_find(inode
);
66 read_unlock(&integrity_iint_lock
);
71 static void iint_free(struct integrity_iint_cache
*iint
)
73 kfree(iint
->ima_hash
);
74 iint
->ima_hash
= NULL
;
77 iint
->ima_file_status
= INTEGRITY_UNKNOWN
;
78 iint
->ima_mmap_status
= INTEGRITY_UNKNOWN
;
79 iint
->ima_bprm_status
= INTEGRITY_UNKNOWN
;
80 iint
->ima_module_status
= INTEGRITY_UNKNOWN
;
81 iint
->evm_status
= INTEGRITY_UNKNOWN
;
82 kmem_cache_free(iint_cache
, iint
);
86 * integrity_inode_get - find or allocate an iint associated with an inode
87 * @inode: pointer to the inode
88 * @return: allocated iint
90 * Caller must lock i_mutex
92 struct integrity_iint_cache
*integrity_inode_get(struct inode
*inode
)
95 struct rb_node
*node
, *parent
= NULL
;
96 struct integrity_iint_cache
*iint
, *test_iint
;
98 iint
= integrity_iint_find(inode
);
102 iint
= kmem_cache_alloc(iint_cache
, GFP_NOFS
);
106 write_lock(&integrity_iint_lock
);
108 p
= &integrity_iint_tree
.rb_node
;
111 test_iint
= rb_entry(parent
, struct integrity_iint_cache
,
113 if (inode
< test_iint
->inode
)
120 node
= &iint
->rb_node
;
121 inode
->i_flags
|= S_IMA
;
122 rb_link_node(node
, parent
, p
);
123 rb_insert_color(node
, &integrity_iint_tree
);
125 write_unlock(&integrity_iint_lock
);
130 * integrity_inode_free - called on security_inode_free
131 * @inode: pointer to the inode
133 * Free the integrity information(iint) associated with an inode.
135 void integrity_inode_free(struct inode
*inode
)
137 struct integrity_iint_cache
*iint
;
142 write_lock(&integrity_iint_lock
);
143 iint
= __integrity_iint_find(inode
);
144 rb_erase(&iint
->rb_node
, &integrity_iint_tree
);
145 write_unlock(&integrity_iint_lock
);
150 static void init_once(void *foo
)
152 struct integrity_iint_cache
*iint
= foo
;
154 memset(iint
, 0, sizeof *iint
);
157 iint
->ima_file_status
= INTEGRITY_UNKNOWN
;
158 iint
->ima_mmap_status
= INTEGRITY_UNKNOWN
;
159 iint
->ima_bprm_status
= INTEGRITY_UNKNOWN
;
160 iint
->ima_module_status
= INTEGRITY_UNKNOWN
;
161 iint
->evm_status
= INTEGRITY_UNKNOWN
;
164 static int __init
integrity_iintcache_init(void)
167 kmem_cache_create("iint_cache", sizeof(struct integrity_iint_cache
),
168 0, SLAB_PANIC
, init_once
);
169 iint_initialized
= 1;
172 security_initcall(integrity_iintcache_init
);