diff options
Diffstat (limited to 'drivers/crypto/padlock-aes.c')
| -rw-r--r-- | drivers/crypto/padlock-aes.c | 81 |
1 files changed, 46 insertions, 35 deletions
diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c index 87f92c39b5f..e1d8776c697 100644 --- a/drivers/crypto/padlock-aes.c +++ b/drivers/crypto/padlock-aes.c @@ -18,9 +18,17 @@ #include <linux/percpu.h> #include <linux/smp.h> #include <asm/byteorder.h> +#include <asm/processor.h> #include <asm/i387.h> #include "padlock.h" +/* number of data blocks actually fetched for each xcrypt insn */ +static unsigned int ecb_fetch_blocks = 2; +static unsigned int cbc_fetch_blocks = 1; + +#define ecb_fetch_bytes (ecb_fetch_blocks * AES_BLOCK_SIZE) +#define cbc_fetch_bytes (cbc_fetch_blocks * AES_BLOCK_SIZE) + /* Control word. */ struct cword { unsigned int __attribute__ ((__packed__)) @@ -173,63 +181,59 @@ static inline void padlock_store_cword(struct cword *cword) */ static inline void padlock_xcrypt(const u8 *input, u8 *output, void *key, - struct cword *control_word) + struct cword *control_word, int count) { asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ : "+S"(input), "+D"(output) - : "d"(control_word), "b"(key), "c"(1)); + : "d"(control_word), "b"(key), "c"(count)); } -static void aes_crypt_copy(const u8 *in, u8 *out, u32 *key, struct cword *cword) +static void aes_crypt_copy(const u8 *in, u8 *out, u32 *key, + struct cword *cword, int count) { - u8 buf[AES_BLOCK_SIZE * 2 + PADLOCK_ALIGNMENT - 1]; + /* + * Padlock prefetches extra data so we must provide mapped input buffers. + * Assume there are at least 16 bytes of stack already in use. + */ + u8 buf[AES_BLOCK_SIZE * 7 + PADLOCK_ALIGNMENT - 1]; u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT); - memcpy(tmp, in, AES_BLOCK_SIZE); - padlock_xcrypt(tmp, out, key, cword); + memcpy(tmp, in, count * AES_BLOCK_SIZE); + padlock_xcrypt(tmp, out, key, cword, count); } static inline void aes_crypt(const u8 *in, u8 *out, u32 *key, - struct cword *cword) + struct cword *cword, int count) { - /* padlock_xcrypt requires at least two blocks of data. */ - if (unlikely(!(((unsigned long)in ^ (PAGE_SIZE - AES_BLOCK_SIZE)) & - (PAGE_SIZE - 1)))) { - aes_crypt_copy(in, out, key, cword); + /* Padlock in ECB mode fetches at least ecb_fetch_bytes of data. + * We could avoid some copying here but it's probably not worth it. + */ + if (unlikely(((unsigned long)in & PAGE_SIZE) + ecb_fetch_bytes > PAGE_SIZE)) { + aes_crypt_copy(in, out, key, cword, count); return; } - padlock_xcrypt(in, out, key, cword); + padlock_xcrypt(in, out, key, cword, count); } static inline void padlock_xcrypt_ecb(const u8 *input, u8 *output, void *key, void *control_word, u32 count) { - if (count == 1) { - aes_crypt(input, output, key, control_word); + u32 initial = count & (ecb_fetch_blocks - 1); + + if (count < ecb_fetch_blocks) { + aes_crypt(input, output, key, control_word, count); return; } - asm volatile ("test $1, %%cl;" - "je 1f;" -#ifndef CONFIG_X86_64 - "lea -1(%%ecx), %%eax;" - "mov $1, %%ecx;" -#else - "lea -1(%%rcx), %%rax;" - "mov $1, %%rcx;" -#endif - ".byte 0xf3,0x0f,0xa7,0xc8;" /* rep xcryptecb */ -#ifndef CONFIG_X86_64 - "mov %%eax, %%ecx;" -#else - "mov %%rax, %%rcx;" -#endif - "1:" - ".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ + if (initial) + asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ + : "+S"(input), "+D"(output) + : "d"(control_word), "b"(key), "c"(initial)); + + asm volatile (".byte 0xf3,0x0f,0xa7,0xc8" /* rep xcryptecb */ : "+S"(input), "+D"(output) - : "d"(control_word), "b"(key), "c"(count) - : "ax"); + : "d"(control_word), "b"(key), "c"(count - initial)); } static inline u8 *padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key, @@ -249,7 +253,7 @@ static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) padlock_reset_key(&ctx->cword.encrypt); ts_state = irq_ts_save(); - aes_crypt(in, out, ctx->E, &ctx->cword.encrypt); + aes_crypt(in, out, ctx->E, &ctx->cword.encrypt, 1); irq_ts_restore(ts_state); padlock_store_cword(&ctx->cword.encrypt); } @@ -261,7 +265,7 @@ static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) padlock_reset_key(&ctx->cword.encrypt); ts_state = irq_ts_save(); - aes_crypt(in, out, ctx->D, &ctx->cword.decrypt); + aes_crypt(in, out, ctx->D, &ctx->cword.decrypt, 1); irq_ts_restore(ts_state); padlock_store_cword(&ctx->cword.encrypt); } @@ -454,6 +458,7 @@ static struct crypto_alg cbc_aes_alg = { static int __init padlock_init(void) { int ret; + struct cpuinfo_x86 *c = &cpu_data(0); if (!cpu_has_xcrypt) { printk(KERN_NOTICE PFX "VIA PadLock not detected.\n"); @@ -476,6 +481,12 @@ static int __init padlock_init(void) printk(KERN_NOTICE PFX "Using VIA PadLock ACE for AES algorithm.\n"); + if (c->x86 == 6 && c->x86_model == 15 && c->x86_mask == 2) { + ecb_fetch_blocks = 8; + cbc_fetch_blocks = 4; /* NOTE: notused */ + printk(KERN_NOTICE PFX "VIA Nano stepping 2 detected: enabling workaround.\n"); + } + out: return ret; |