Skip to content
GitLab
Projects
Groups
Snippets
Help
Loading...
Help
What's new
7
Help
Support
Community forum
Keyboard shortcuts
?
Submit feedback
Contribute to GitLab
Sign in / Register
Toggle navigation
Open sidebar
Wim Lewis
nettle
Commits
8cf98222
Commit
8cf98222
authored
Apr 13, 2012
by
Niels Möller
Browse files
Options
Browse Files
Download
Email Patches
Plain Diff
Simplified aes_set_encrypt_key.
parent
5ff8ded5
Changes
2
Hide whitespace changes
Inline
Side-by-side
Showing
2 changed files
with
16 additions
and
28 deletions
+16
-28
ChangeLog
ChangeLog
+4
-0
aes-set-encrypt-key.c
aes-set-encrypt-key.c
+12
-28
No files found.
ChangeLog
View file @
8cf98222
2012-04-13 Niels Möller <nisse@lysator.liu.se>
* aes-set-encrypt-key.c (aes_set_encrypt_key): Use LE_READ_UINT32.
Tabulate the needed "round constants".
(xtime): Deleted function.
* aes-internal.h (SUBBYTE): Cast to uint32_t. Use B0, ..., B3
macros.
...
...
aes-set-encrypt-key.c
View file @
8cf98222
...
...
@@ -34,26 +34,16 @@
#include "aes-internal.h"
#include "macros.h"
static
unsigned
xtime
(
unsigned
x
)
{
assert
(
x
<
0x100
);
x
<<=
1
;
if
(
x
&
0x100
)
x
^=
0x11b
;
assert
(
x
<
0x100
);
return
x
;
}
void
aes_set_encrypt_key
(
struct
aes_ctx
*
ctx
,
unsigned
keysize
,
const
uint8_t
*
key
)
{
static
const
uint8_t
rcon
[
10
]
=
{
0x01
,
0x02
,
0x04
,
0x08
,
0x10
,
0x20
,
0x40
,
0x80
,
0x1b
,
0x36
,
};
unsigned
nk
,
nr
,
i
,
lastkey
;
uint32_t
temp
,
rcon
;
uint32_t
temp
;
const
uint8_t
*
rp
;
assert
(
keysize
>=
AES_MIN_KEY_SIZE
);
assert
(
keysize
<=
AES_MAX_KEY_SIZE
);
...
...
@@ -72,25 +62,19 @@ aes_set_encrypt_key(struct aes_ctx *ctx,
lastkey
=
(
AES_BLOCK_SIZE
/
4
)
*
(
nr
+
1
);
ctx
->
nrounds
=
nr
;
rcon
=
1
;
for
(
i
=
0
;
i
<
nk
;
i
++
)
{
ctx
->
keys
[
i
]
=
key
[
i
*
4
]
+
(
key
[
i
*
4
+
1
]
<<
8
)
+
(
key
[
i
*
4
+
2
]
<<
16
)
+
(
key
[
i
*
4
+
3
]
<<
24
);
}
for
(
i
=
0
,
rp
=
rcon
;
i
<
nk
;
i
++
)
ctx
->
keys
[
i
]
=
LE_READ_UINT32
(
key
+
i
*
4
);
for
(
i
=
nk
;
i
<
lastkey
;
i
++
)
{
temp
=
ctx
->
keys
[
i
-
1
];
if
(
i
%
nk
==
0
)
{
temp
=
SUBBYTE
(
ROTL32
(
24
,
temp
),
aes_sbox
)
^
rcon
;
rcon
=
(
uint32_t
)
xtime
((
uint8_t
)
rcon
&
0xff
);
}
temp
=
SUBBYTE
(
ROTL32
(
24
,
temp
),
aes_sbox
)
^
*
rp
++
;
else
if
(
nk
>
6
&&
(
i
%
nk
)
==
4
)
{
temp
=
SUBBYTE
(
temp
,
aes_sbox
);
}
temp
=
SUBBYTE
(
temp
,
aes_sbox
);
ctx
->
keys
[
i
]
=
ctx
->
keys
[
i
-
nk
]
^
temp
;
}
}
...
...
Write
Preview
Markdown
is supported
0%
Try again
or
attach a new file
.
Attach a file
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Cancel
Please
register
or
sign in
to comment