2 * Driver for /dev/crypto device (aka CryptoDev)
4 * Copyright (c) 2009-2011 Nikos Mavrogiannopoulos <nmav@gnutls.org>
5 * Copyright (c) 2010 Phil Sutter
6 * Copyright (c) 2011, 2012 OpenSSL Software Foundation, Inc.
8 * This file is part of linux cryptodev.
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version 2
13 * of the License, or (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
26 #include <crypto/hash.h>
27 #include <linux/crypto.h>
29 #include <linux/highmem.h>
30 #include <linux/ioctl.h>
31 #include <linux/random.h>
32 #include <linux/syscalls.h>
33 #include <linux/pagemap.h>
34 #include <linux/uaccess.h>
35 #include <crypto/scatterwalk.h>
36 #include <linux/scatterlist.h>
37 #include "cryptodev_int.h"
41 /* Helper functions to assist zero copy.
42 * This needs to be redesigned and moved out of the session. --nmav
45 /* offset of buf in it's first page */
46 #define PAGEOFFSET(buf) ((unsigned long)buf & ~PAGE_MASK)
48 /* fetch the pages addr resides in into pg and initialise sg with them */
49 int __get_userbuf(uint8_t __user
*addr
, uint32_t len
, int write
,
50 int pgcount
, struct page
**pg
, struct scatterlist
*sg
,
51 struct task_struct
*task
, struct mm_struct
*mm
)
53 int ret
, pglen
, i
= 0;
54 struct scatterlist
*sgp
;
56 down_write(&mm
->mmap_sem
);
57 ret
= get_user_pages(task
, mm
,
58 (unsigned long)addr
, pgcount
, write
, 0, pg
, NULL
);
59 up_write(&mm
->mmap_sem
);
63 sg_init_table(sg
, pgcount
);
65 pglen
= min((ptrdiff_t)(PAGE_SIZE
- PAGEOFFSET(addr
)), (ptrdiff_t)len
);
66 sg_set_page(sg
, pg
[i
++], pglen
, PAGEOFFSET(addr
));
69 for (sgp
= sg_next(sg
); len
; sgp
= sg_next(sgp
)) {
70 pglen
= min((uint32_t)PAGE_SIZE
, len
);
71 sg_set_page(sgp
, pg
[i
++], pglen
, 0);
74 sg_mark_end(sg_last(sg
, pgcount
));
78 int adjust_sg_array(struct csession
* ses
, int pagecount
)
80 struct scatterlist
*sg
;
84 for (array_size
= ses
->array_size
; array_size
< pagecount
;
88 dprintk(2, KERN_DEBUG
, "%s: reallocating to %d elements\n",
89 __func__
, array_size
);
90 pages
= krealloc(ses
->pages
, array_size
* sizeof(struct page
*),
95 sg
= krealloc(ses
->sg
, array_size
* sizeof(struct scatterlist
),
100 ses
->array_size
= array_size
;
105 void release_user_pages(struct page
**pg
, int pagecount
)
107 while (pagecount
--) {
108 if (!PageReserved(pg
[pagecount
]))
109 SetPageDirty(pg
[pagecount
]);
110 page_cache_release(pg
[pagecount
]);
114 /* make src and dst available in scatterlists.
115 * dst might be the same as src.
117 int get_userbuf(struct csession
*ses
, void* __user src
, int src_len
,
118 void* __user dst
, int dst_len
,
119 struct task_struct
*task
, struct mm_struct
*mm
,
120 struct scatterlist
**src_sg
,
121 struct scatterlist
**dst_sg
,
124 int src_pagecount
, dst_pagecount
= 0, pagecount
, write_src
= 1;
130 if (ses
->alignmask
&& !IS_ALIGNED((unsigned long)src
, ses
->alignmask
)) {
131 dprintk(2, KERN_WARNING
, "%s: careful - source address %lx is not %d byte aligned\n",
132 __func__
, (unsigned long)src
, ses
->alignmask
+ 1);
137 src_len
= max(src_len
, dst_len
);
141 src_pagecount
= PAGECOUNT(src
, src_len
);
142 if (!ses
->cdata
.init
) { /* hashing only */
144 } else if (src
!= dst
) { /* non-in-situ transformation */
148 dst_pagecount
= PAGECOUNT(dst
, dst_len
);
151 if (ses
->alignmask
&& !IS_ALIGNED((unsigned long)dst
, ses
->alignmask
)) {
152 dprintk(2, KERN_WARNING
, "%s: careful - destination address %lx is not %d byte aligned\n",
153 __func__
, (unsigned long)dst
, ses
->alignmask
+ 1);
156 (*tot_pages
) = pagecount
= src_pagecount
+ dst_pagecount
;
158 if (pagecount
> ses
->array_size
) {
159 rc
= adjust_sg_array(ses
, pagecount
);
164 rc
= __get_userbuf(src
, src_len
, write_src
, src_pagecount
,
165 ses
->pages
, ses
->sg
, task
, mm
);
168 "failed to get user pages for data input\n");
171 (*src_sg
) = (*dst_sg
) = ses
->sg
;
176 (*dst_sg
) = ses
->sg
+ src_pagecount
;
178 rc
= __get_userbuf(dst
, dst_len
, 1, dst_pagecount
,
179 ses
->pages
+ src_pagecount
, *dst_sg
,
183 "failed to get user pages for data output\n");
184 release_user_pages(ses
->pages
, src_pagecount
);