[PADLOCK] Move fast path work into aes_set_key and upper layer
Most of the work done aes_padlock can be done in aes_set_key. This
means that we only have to do it once when the key changes rather
than every time we perform an encryption or decryption.
This patch also sets cra_alignmask to let the upper layer ensure
that the buffers fed to us are aligned correctly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c
index ed708b4..5f28909 100644
--- a/drivers/crypto/padlock-aes.c
+++ b/drivers/crypto/padlock-aes.c
@@ -49,6 +49,7 @@
#include <linux/errno.h>
#include <linux/crypto.h>
#include <linux/interrupt.h>
+#include <linux/kernel.h>
#include <asm/byteorder.h>
#include "padlock.h"
@@ -59,8 +60,12 @@
#define AES_EXTENDED_KEY_SIZE_B (AES_EXTENDED_KEY_SIZE * sizeof(uint32_t))
struct aes_ctx {
- uint32_t e_data[AES_EXTENDED_KEY_SIZE+4];
- uint32_t d_data[AES_EXTENDED_KEY_SIZE+4];
+ uint32_t e_data[AES_EXTENDED_KEY_SIZE];
+ uint32_t d_data[AES_EXTENDED_KEY_SIZE];
+ struct {
+ struct cword encrypt;
+ struct cword decrypt;
+ } cword;
uint32_t *E;
uint32_t *D;
int key_length;
@@ -280,10 +285,15 @@
return 0;
}
+static inline struct aes_ctx *aes_ctx(void *ctx)
+{
+ return (struct aes_ctx *)ALIGN((unsigned long)ctx, PADLOCK_ALIGNMENT);
+}
+
static int
aes_set_key(void *ctx_arg, const uint8_t *in_key, unsigned int key_len, uint32_t *flags)
{
- struct aes_ctx *ctx = ctx_arg;
+ struct aes_ctx *ctx = aes_ctx(ctx_arg);
uint32_t i, t, u, v, w;
uint32_t P[AES_EXTENDED_KEY_SIZE];
uint32_t rounds;
@@ -295,25 +305,36 @@
ctx->key_length = key_len;
+ /*
+ * If the hardware is capable of generating the extended key
+ * itself we must supply the plain key for both encryption
+ * and decryption.
+ */
ctx->E = ctx->e_data;
- ctx->D = ctx->d_data;
-
- /* Ensure 16-Bytes alignmentation of keys for VIA PadLock. */
- if ((int)(ctx->e_data) & 0x0F)
- ctx->E += 4 - (((int)(ctx->e_data) & 0x0F) / sizeof (ctx->e_data[0]));
-
- if ((int)(ctx->d_data) & 0x0F)
- ctx->D += 4 - (((int)(ctx->d_data) & 0x0F) / sizeof (ctx->d_data[0]));
+ ctx->D = ctx->e_data;
E_KEY[0] = uint32_t_in (in_key);
E_KEY[1] = uint32_t_in (in_key + 4);
E_KEY[2] = uint32_t_in (in_key + 8);
E_KEY[3] = uint32_t_in (in_key + 12);
+ /* Prepare control words. */
+ memset(&ctx->cword, 0, sizeof(ctx->cword));
+
+ ctx->cword.decrypt.encdec = 1;
+ ctx->cword.encrypt.rounds = 10 + (key_len - 16) / 4;
+ ctx->cword.decrypt.rounds = ctx->cword.encrypt.rounds;
+ ctx->cword.encrypt.ksize = (key_len - 16) / 8;
+ ctx->cword.decrypt.ksize = ctx->cword.encrypt.ksize;
+
/* Don't generate extended keys if the hardware can do it. */
if (aes_hw_extkey_available(key_len))
return 0;
+ ctx->D = ctx->d_data;
+ ctx->cword.encrypt.keygen = 1;
+ ctx->cword.decrypt.keygen = 1;
+
switch (key_len) {
case 16:
t = E_KEY[3];
@@ -370,9 +391,8 @@
/* ====== Encryption/decryption routines ====== */
/* This is the real call to PadLock. */
-static inline void
-padlock_xcrypt_ecb(uint8_t *input, uint8_t *output, uint8_t *key,
- void *control_word, uint32_t count)
+static inline void padlock_xcrypt_ecb(const u8 *input, u8 *output, void *key,
+ void *control_word, u32 count)
{
asm volatile ("pushfl; popfl"); /* enforce key reload. */
asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */
@@ -381,66 +401,26 @@
}
static void
-aes_padlock(void *ctx_arg, uint8_t *out_arg, const uint8_t *in_arg, int encdec)
-{
- /* Don't blindly modify this structure - the items must
- fit on 16-Bytes boundaries! */
- struct padlock_xcrypt_data {
- uint8_t buf[AES_BLOCK_SIZE];
- union cword cword;
- };
-
- struct aes_ctx *ctx = ctx_arg;
- char bigbuf[sizeof(struct padlock_xcrypt_data) + 16];
- struct padlock_xcrypt_data *data;
- void *key;
-
- /* Place 'data' at the first 16-Bytes aligned address in 'bigbuf'. */
- if (((long)bigbuf) & 0x0F)
- data = (void*)(bigbuf + 16 - ((long)bigbuf & 0x0F));
- else
- data = (void*)bigbuf;
-
- /* Prepare Control word. */
- memset (data, 0, sizeof(struct padlock_xcrypt_data));
- data->cword.b.encdec = !encdec; /* in the rest of cryptoapi ENC=1/DEC=0 */
- data->cword.b.rounds = 10 + (ctx->key_length - 16) / 4;
- data->cword.b.ksize = (ctx->key_length - 16) / 8;
-
- /* Is the hardware capable to generate the extended key? */
- if (!aes_hw_extkey_available(ctx->key_length))
- data->cword.b.keygen = 1;
-
- /* ctx->E starts with a plain key - if the hardware is capable
- to generate the extended key itself we must supply
- the plain key for both Encryption and Decryption. */
- if (encdec == CRYPTO_DIR_ENCRYPT || data->cword.b.keygen == 0)
- key = ctx->E;
- else
- key = ctx->D;
-
- memcpy(data->buf, in_arg, AES_BLOCK_SIZE);
- padlock_xcrypt_ecb(data->buf, data->buf, key, &data->cword, 1);
- memcpy(out_arg, data->buf, AES_BLOCK_SIZE);
-}
-
-static void
aes_encrypt(void *ctx_arg, uint8_t *out, const uint8_t *in)
{
- aes_padlock(ctx_arg, out, in, CRYPTO_DIR_ENCRYPT);
+ struct aes_ctx *ctx = aes_ctx(ctx_arg);
+ padlock_xcrypt_ecb(in, out, ctx->E, &ctx->cword.encrypt, 1);
}
static void
aes_decrypt(void *ctx_arg, uint8_t *out, const uint8_t *in)
{
- aes_padlock(ctx_arg, out, in, CRYPTO_DIR_DECRYPT);
+ struct aes_ctx *ctx = aes_ctx(ctx_arg);
+ padlock_xcrypt_ecb(in, out, ctx->D, &ctx->cword.decrypt, 1);
}
static struct crypto_alg aes_alg = {
.cra_name = "aes",
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = AES_BLOCK_SIZE,
- .cra_ctxsize = sizeof(struct aes_ctx),
+ .cra_ctxsize = sizeof(struct aes_ctx) +
+ PADLOCK_ALIGNMENT,
+ .cra_alignmask = PADLOCK_ALIGNMENT - 1,
.cra_module = THIS_MODULE,
.cra_list = LIST_HEAD_INIT(aes_alg.cra_list),
.cra_u = {
diff --git a/drivers/crypto/padlock.h b/drivers/crypto/padlock.h
index 7a50060..3cf2b7a 100644
--- a/drivers/crypto/padlock.h
+++ b/drivers/crypto/padlock.h
@@ -13,18 +13,18 @@
#ifndef _CRYPTO_PADLOCK_H
#define _CRYPTO_PADLOCK_H
+#define PADLOCK_ALIGNMENT 16
+
/* Control word. */
-union cword {
- uint32_t cword[4];
- struct {
- int rounds:4;
- int algo:3;
- int keygen:1;
- int interm:1;
- int encdec:1;
- int ksize:2;
- } b;
-};
+struct cword {
+ int __attribute__ ((__packed__))
+ rounds:4,
+ algo:3,
+ keygen:1,
+ interm:1,
+ encdec:1,
+ ksize:2;
+} __attribute__ ((__aligned__(PADLOCK_ALIGNMENT)));
#define PFX "padlock: "
