xref: /openbsd/sys/uvm/uvm_swap_encrypt.h (revision ba832b00)
1 /*	$OpenBSD: uvm_swap_encrypt.h,v 1.14 2024/11/07 09:04:55 jsg Exp $	*/
2 
3 /*
4  * Copyright 1999 Niels Provos <provos@citi.umich.edu>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Niels Provos.
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef _UVM_SWAP_ENCRYPT_H
34 #define _UVM_SWAP_ENCRYPT_H
35 
36 #define SWPENC_ENABLE	0
37 #define SWPENC_CREATED	1
38 #define SWPENC_DELETED	2
39 #define SWPENC_MAXID	3
40 
41 #define CTL_SWPENC_NAMES { \
42 	{ "enable", CTLTYPE_INT }, \
43 	{ "keyscreated", CTLTYPE_INT }, \
44 	{ "keysdeleted", CTLTYPE_INT }, \
45 }
46 
47 #define SWAP_KEY_SIZE	4		/* 128-bit keys */
48 
49 struct swap_key {
50 	u_int32_t key[SWAP_KEY_SIZE];	/* secret key for swap range */
51 	u_int16_t refcount;		/* pages that still need it */
52 };
53 
54 int swap_encrypt_ctl(int *, u_int, void *, size_t *, void *, size_t,
55 			  struct proc *);
56 
57 void swap_encrypt(struct swap_key *,caddr_t, caddr_t, u_int64_t, size_t);
58 void swap_decrypt(struct swap_key *,caddr_t, caddr_t, u_int64_t, size_t);
59 
60 void swap_key_cleanup(struct swap_key *);
61 void swap_key_prepare(struct swap_key *, int);
62 
63 void swap_key_create(struct swap_key *);
64 void swap_key_delete(struct swap_key *);
65 
66 static inline void
swap_key_get(struct swap_key * key)67 swap_key_get(struct swap_key *key)
68 {
69 	if (key->refcount == 0)
70 		swap_key_create(key);
71 	key->refcount++;
72 }
73 
74 static inline void
swap_key_put(struct swap_key * key)75 swap_key_put(struct swap_key *key)
76 {
77 	key->refcount--;
78 	if (key->refcount == 0)
79 		swap_key_delete(key);
80 }
81 
82 extern int uvm_doswapencrypt;		/* swapencrypt enabled/disabled */
83 extern int swap_encrypt_initialized;
84 
85 #endif /* _UVM_SWAP_ENCRYPT_H */
86