From 6789b2dc455b90efc9c88886c9366adc9abb7347 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 6 Jul 2005 13:52:27 -0700 Subject: [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 Signed-off-by: David S. Miller --- drivers/crypto/padlock-aes.c | 102 +++++++++++++++++-------------------------- drivers/crypto/padlock.h | 22 +++++----- 2 files changed, 52 insertions(+), 72 deletions(-) (limited to 'drivers/crypto') diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c index ed708b4427b..5f28909d401 100644 --- a/drivers/crypto/padlock-aes.c +++ b/drivers/crypto/padlock-aes.c @@ -49,6 +49,7 @@ #include #include #include +#include #include #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 @@ aes_hw_extkey_available(uint8_t key_len) 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 @@ aes_set_key(void *ctx_arg, const uint8_t *in_key, unsigned int key_len, uint32_t 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 @@ aes_set_key(void *ctx_arg, const uint8_t *in_key, unsigned int key_len, uint32_t /* ====== 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 */ @@ -380,67 +400,27 @@ padlock_xcrypt_ecb(uint8_t *input, uint8_t *output, uint8_t *key, : "d"(control_word), "b"(key), "c"(count)); } -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 7a500605e44..3cf2b7a1234 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: " -- cgit v1.2.3