From: "Huang, Ying" Subject: [PATCH -mm crypto] AES: remove crypto_fl_tab and replace crypto_il_tab with isb_tab Date: Tue, 11 Mar 2008 12:42:56 +0800 Message-ID: <1205210576.3676.7.camel@caritas-dev.intel.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org To: Herbert Xu , "Adam J. Richter" , Alexander Kjeldaas Return-path: Received: from mga02.intel.com ([134.134.136.20]:4100 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751368AbYCKEm0 (ORCPT ); Tue, 11 Mar 2008 00:42:26 -0400 Sender: linux-crypto-owner@vger.kernel.org List-ID: Remove crypto_fl_tab from aes implementation. Because mix_col(1,n) = n, all information in cryto_fl_tab is in crypto_ft_tab too. crypto_il_tab is replaced by isb_tab, the byte shift is done during decryption. These changes reduce the encryption cache footprint to 50% and decryption cache footprint to 53.1%. The code size is increased slightly. On my Intel CORE micro-architecture CPU, there is almost no performance penalty. This patch has been built and tested against 2.6.25-rc3-mm1. This patch is only for generic C implementation. If this kind of idea is desired, I will implement the ASM version for x86. Signed-off-by: Huang Ying --- crypto/aes_generic.c | 47 ++++++++++++++++------------------------------- include/crypto/aes.h | 2 -- 2 files changed, 16 insertions(+), 33 deletions(-) --- a/crypto/aes_generic.c +++ b/crypto/aes_generic.c @@ -63,18 +63,14 @@ static inline u8 byte(const u32 x, const static u8 pow_tab[256] __initdata; static u8 log_tab[256] __initdata; static u8 sbx_tab[256] __initdata; -static u8 isb_tab[256] __initdata; +static u8 isb_tab[256]; static u32 rco_tab[10]; u32 crypto_ft_tab[4][256]; -u32 crypto_fl_tab[4][256]; u32 crypto_it_tab[4][256]; -u32 crypto_il_tab[4][256]; EXPORT_SYMBOL_GPL(crypto_ft_tab); -EXPORT_SYMBOL_GPL(crypto_fl_tab); EXPORT_SYMBOL_GPL(crypto_it_tab); -EXPORT_SYMBOL_GPL(crypto_il_tab); static inline u8 __init f_mult(u8 a, u8 b) { @@ -122,12 +118,6 @@ static void __init gen_tabs(void) for (i = 0; i < 256; ++i) { p = sbx_tab[i]; - t = p; - crypto_fl_tab[0][i] = t; - crypto_fl_tab[1][i] = rol32(t, 8); - crypto_fl_tab[2][i] = rol32(t, 16); - crypto_fl_tab[3][i] = rol32(t, 24); - t = ((u32) ff_mult(2, p)) | ((u32) p << 8) | ((u32) p << 16) | ((u32) ff_mult(3, p) << 24); @@ -139,12 +129,6 @@ static void __init gen_tabs(void) p = isb_tab[i]; - t = p; - crypto_il_tab[0][i] = t; - crypto_il_tab[1][i] = rol32(t, 8); - crypto_il_tab[2][i] = rol32(t, 16); - crypto_il_tab[3][i] = rol32(t, 24); - t = ((u32) ff_mult(14, p)) | ((u32) ff_mult(9, p) << 8) | ((u32) ff_mult(13, p) << 16) | @@ -173,10 +157,10 @@ static void __init gen_tabs(void) } while (0) #define ls_box(x) \ - crypto_fl_tab[0][byte(x, 0)] ^ \ - crypto_fl_tab[1][byte(x, 1)] ^ \ - crypto_fl_tab[2][byte(x, 2)] ^ \ - crypto_fl_tab[3][byte(x, 3)] + (crypto_ft_tab[2][byte(x, 0)] & 0x000000ff) ^ \ + (crypto_ft_tab[3][byte(x, 1)] & 0x0000ff00) ^ \ + (crypto_ft_tab[0][byte(x, 2)] & 0x00ff0000) ^ \ + (crypto_ft_tab[1][byte(x, 3)] & 0xff000000) #define loop4(i) do { \ t = ror32(t, 8); \ @@ -303,11 +287,12 @@ EXPORT_SYMBOL_GPL(crypto_aes_set_key); k += 4; \ } while (0) -#define f_rl(bo, bi, n, k) do { \ - bo[n] = crypto_fl_tab[0][byte(bi[n], 0)] ^ \ - crypto_fl_tab[1][byte(bi[(n + 1) & 3], 1)] ^ \ - crypto_fl_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \ - crypto_fl_tab[3][byte(bi[(n + 3) & 3], 3)] ^ *(k + n); \ +#define f_rl(bo, bi, n, k) do { \ + bo[n] = (crypto_ft_tab[2][byte(bi[n], 0)] & 0x000000ff) ^ \ + (crypto_ft_tab[3][byte(bi[(n + 1) & 3], 1)] & 0x0000ff00) ^ \ + (crypto_ft_tab[0][byte(bi[(n + 2) & 3], 2)] & 0x00ff0000) ^ \ + (crypto_ft_tab[1][byte(bi[(n + 3) & 3], 3)] & 0xff000000) ^ \ + *(k + n); \ } while (0) #define f_lround(bo, bi, k) do {\ @@ -375,11 +360,11 @@ static void aes_encrypt(struct crypto_tf k += 4; \ } while (0) -#define i_rl(bo, bi, n, k) do { \ - bo[n] = crypto_il_tab[0][byte(bi[n], 0)] ^ \ - crypto_il_tab[1][byte(bi[(n + 3) & 3], 1)] ^ \ - crypto_il_tab[2][byte(bi[(n + 2) & 3], 2)] ^ \ - crypto_il_tab[3][byte(bi[(n + 1) & 3], 3)] ^ *(k + n); \ +#define i_rl(bo, bi, n, k) do { \ + bo[n] = (u32)isb_tab[byte(bi[n], 0)] ^ \ + ((u32)isb_tab[byte(bi[(n + 3) & 3], 1)] << 8) ^ \ + ((u32)isb_tab[byte(bi[(n + 2) & 3], 2)] << 16) ^ \ + ((u32)isb_tab[byte(bi[(n + 1) & 3], 3)] << 24) ^ *(k + n); \ } while (0) #define i_lround(bo, bi, k) do {\ --- a/include/crypto/aes.h +++ b/include/crypto/aes.h @@ -22,9 +22,7 @@ struct crypto_aes_ctx { }; extern u32 crypto_ft_tab[4][256]; -extern u32 crypto_fl_tab[4][256]; extern u32 crypto_it_tab[4][256]; -extern u32 crypto_il_tab[4][256]; int crypto_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, unsigned int key_len);