From 476df259cd577e20379b02a7f7ffd086ea925a83 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 6 Jul 2005 13:54:09 -0700 Subject: [PATCH] [CRYPTO] Update IV correctly for Padlock CBC encryption When the Padlock does CBC encryption, the memory pointed to by EAX is not updated at all. Instead, it updates the value of EAX by pointing it to the last block in the output. Therefore to maintain the correct semantics we need to copy the IV. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- drivers/crypto/padlock-aes.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c index c5b58fae95f2..71407c578afe 100644 --- a/drivers/crypto/padlock-aes.c +++ b/drivers/crypto/padlock-aes.c @@ -400,8 +400,8 @@ static inline void padlock_xcrypt_ecb(const u8 *input, u8 *output, void *key, : "d"(control_word), "b"(key), "c"(count)); } -static inline void padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key, - u8 *iv, void *control_word, u32 count) +static inline u8 *padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key, + u8 *iv, void *control_word, u32 count) { /* Enforce key reload. */ asm volatile ("pushfl; popfl"); @@ -409,6 +409,7 @@ static inline void padlock_xcrypt_cbc(const u8 *input, u8 *output, void *key, asm volatile (".byte 0xf3,0x0f,0xa7,0xd0" : "+S" (input), "+D" (output), "+a" (iv) : "d" (control_word), "b" (key), "c" (count)); + return iv; } static void @@ -447,8 +448,12 @@ static unsigned int aes_encrypt_cbc(const struct cipher_desc *desc, u8 *out, const u8 *in, unsigned int nbytes) { struct aes_ctx *ctx = aes_ctx(crypto_tfm_ctx(desc->tfm)); - padlock_xcrypt_cbc(in, out, ctx->E, desc->info, &ctx->cword.encrypt, - nbytes / AES_BLOCK_SIZE); + u8 *iv; + + iv = padlock_xcrypt_cbc(in, out, ctx->E, desc->info, + &ctx->cword.encrypt, nbytes / AES_BLOCK_SIZE); + memcpy(desc->info, iv, AES_BLOCK_SIZE); + return nbytes & ~(AES_BLOCK_SIZE - 1); }