From 7012c04ef3dea6ab05cab74879e1ab97c7a086e2 Mon Sep 17 00:00:00 2001 From: Philippe Reynes Date: Mon, 6 Jan 2020 15:22:34 +0100 Subject: aes: add a define for the size of a block In the code, we use the size of the key for the size of the block. It's true when the key is 128 bits, but it become false for key of 192 bits and 256 bits. So to prepare the support of aes192 and 256, we introduce a constant for the iaes block size. Signed-off-by: Philippe Reynes Reviewed-by: Simon Glass --- lib/aes.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-) (limited to 'lib/aes.c') diff --git a/lib/aes.c b/lib/aes.c index a12a192..cfa57b6 100644 --- a/lib/aes.c +++ b/lib/aes.c @@ -596,62 +596,62 @@ void aes_apply_cbc_chain_data(u8 *cbc_chain_data, u8 *src, u8 *dst) { int i; - for (i = 0; i < AES_KEY_LENGTH; i++) + for (i = 0; i < AES_BLOCK_LENGTH; i++) *dst++ = *src++ ^ *cbc_chain_data++; } void aes_cbc_encrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, u32 num_aes_blocks) { - u8 tmp_data[AES_KEY_LENGTH]; + u8 tmp_data[AES_BLOCK_LENGTH]; u8 *cbc_chain_data = iv; u32 i; for (i = 0; i < num_aes_blocks; i++) { debug("encrypt_object: block %d of %d\n", i, num_aes_blocks); - debug_print_vector("AES Src", AES_KEY_LENGTH, src); + debug_print_vector("AES Src", AES_BLOCK_LENGTH, src); /* Apply the chain data */ aes_apply_cbc_chain_data(cbc_chain_data, src, tmp_data); - debug_print_vector("AES Xor", AES_KEY_LENGTH, tmp_data); + debug_print_vector("AES Xor", AES_BLOCK_LENGTH, tmp_data); /* Encrypt the AES block */ aes_encrypt(tmp_data, key_exp, dst); - debug_print_vector("AES Dst", AES_KEY_LENGTH, dst); + debug_print_vector("AES Dst", AES_BLOCK_LENGTH, dst); /* Update pointers for next loop. */ cbc_chain_data = dst; - src += AES_KEY_LENGTH; - dst += AES_KEY_LENGTH; + src += AES_BLOCK_LENGTH; + dst += AES_BLOCK_LENGTH; } } void aes_cbc_decrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, u32 num_aes_blocks) { - u8 tmp_data[AES_KEY_LENGTH], tmp_block[AES_KEY_LENGTH]; + u8 tmp_data[AES_BLOCK_LENGTH], tmp_block[AES_BLOCK_LENGTH]; /* Convenient array of 0's for IV */ - u8 cbc_chain_data[AES_KEY_LENGTH]; + u8 cbc_chain_data[AES_BLOCK_LENGTH]; u32 i; - memcpy(cbc_chain_data, iv, AES_KEY_LENGTH); + memcpy(cbc_chain_data, iv, AES_BLOCK_LENGTH); for (i = 0; i < num_aes_blocks; i++) { debug("encrypt_object: block %d of %d\n", i, num_aes_blocks); - debug_print_vector("AES Src", AES_KEY_LENGTH, src); + debug_print_vector("AES Src", AES_BLOCK_LENGTH, src); - memcpy(tmp_block, src, AES_KEY_LENGTH); + memcpy(tmp_block, src, AES_BLOCK_LENGTH); /* Decrypt the AES block */ aes_decrypt(src, key_exp, tmp_data); - debug_print_vector("AES Xor", AES_KEY_LENGTH, tmp_data); + debug_print_vector("AES Xor", AES_BLOCK_LENGTH, tmp_data); /* Apply the chain data */ aes_apply_cbc_chain_data(cbc_chain_data, tmp_data, dst); - debug_print_vector("AES Dst", AES_KEY_LENGTH, dst); + debug_print_vector("AES Dst", AES_BLOCK_LENGTH, dst); /* Update pointers for next loop. */ - memcpy(cbc_chain_data, tmp_block, AES_KEY_LENGTH); - src += AES_KEY_LENGTH; - dst += AES_KEY_LENGTH; + memcpy(cbc_chain_data, tmp_block, AES_BLOCK_LENGTH); + src += AES_BLOCK_LENGTH; + dst += AES_BLOCK_LENGTH; } } -- cgit v1.1