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 a12a1920843..cfa57b681c6 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 v1.2.3 From 8302d1708aef720d52942ea47bcebf9c1b8d5de0 Mon Sep 17 00:00:00 2001 From: Philippe Reynes Date: Mon, 6 Jan 2020 15:22:35 +0100 Subject: aes: add support of aes192 and aes256 Until now, we only support aes128. This commit add the support of aes192 and aes256. Signed-off-by: Philippe Reynes Reviewed-by: Simon Glass --- lib/aes.c | 77 ++++++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 54 insertions(+), 23 deletions(-) (limited to 'lib/aes.c') diff --git a/lib/aes.c b/lib/aes.c index cfa57b681c6..ce53c9f1f37 100644 --- a/lib/aes.c +++ b/lib/aes.c @@ -508,50 +508,79 @@ static u8 rcon[11] = { 0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 }; +static u32 aes_get_rounds(u32 key_len) +{ + u32 rounds = AES128_ROUNDS; + + if (key_len == AES192_KEY_LENGTH) + rounds = AES192_ROUNDS; + else if (key_len == AES256_KEY_LENGTH) + rounds = AES256_ROUNDS; + + return rounds; +} + +static u32 aes_get_keycols(u32 key_len) +{ + u32 keycols = AES128_KEYCOLS; + + if (key_len == AES192_KEY_LENGTH) + keycols = AES192_KEYCOLS; + else if (key_len == AES256_KEY_LENGTH) + keycols = AES256_KEYCOLS; + + return keycols; +} + /* produce AES_STATECOLS bytes for each round */ -void aes_expand_key(u8 *key, u8 *expkey) +void aes_expand_key(u8 *key, u32 key_len, u8 *expkey) { u8 tmp0, tmp1, tmp2, tmp3, tmp4; - u32 idx; + u32 idx, aes_rounds, aes_keycols; - memcpy(expkey, key, AES_KEYCOLS * 4); + aes_rounds = aes_get_rounds(key_len); + aes_keycols = aes_get_keycols(key_len); - for (idx = AES_KEYCOLS; idx < AES_STATECOLS * (AES_ROUNDS + 1); idx++) { + memcpy(expkey, key, key_len); + + for (idx = aes_keycols; idx < AES_STATECOLS * (aes_rounds + 1); idx++) { tmp0 = expkey[4*idx - 4]; tmp1 = expkey[4*idx - 3]; tmp2 = expkey[4*idx - 2]; tmp3 = expkey[4*idx - 1]; - if (!(idx % AES_KEYCOLS)) { + if (!(idx % aes_keycols)) { tmp4 = tmp3; tmp3 = sbox[tmp0]; - tmp0 = sbox[tmp1] ^ rcon[idx / AES_KEYCOLS]; + tmp0 = sbox[tmp1] ^ rcon[idx / aes_keycols]; tmp1 = sbox[tmp2]; tmp2 = sbox[tmp4]; - } else if ((AES_KEYCOLS > 6) && (idx % AES_KEYCOLS == 4)) { + } else if ((aes_keycols > 6) && (idx % aes_keycols == 4)) { tmp0 = sbox[tmp0]; tmp1 = sbox[tmp1]; tmp2 = sbox[tmp2]; tmp3 = sbox[tmp3]; } - expkey[4*idx+0] = expkey[4*idx - 4*AES_KEYCOLS + 0] ^ tmp0; - expkey[4*idx+1] = expkey[4*idx - 4*AES_KEYCOLS + 1] ^ tmp1; - expkey[4*idx+2] = expkey[4*idx - 4*AES_KEYCOLS + 2] ^ tmp2; - expkey[4*idx+3] = expkey[4*idx - 4*AES_KEYCOLS + 3] ^ tmp3; + expkey[4*idx+0] = expkey[4*idx - 4*aes_keycols + 0] ^ tmp0; + expkey[4*idx+1] = expkey[4*idx - 4*aes_keycols + 1] ^ tmp1; + expkey[4*idx+2] = expkey[4*idx - 4*aes_keycols + 2] ^ tmp2; + expkey[4*idx+3] = expkey[4*idx - 4*aes_keycols + 3] ^ tmp3; } } /* encrypt one 128 bit block */ -void aes_encrypt(u8 *in, u8 *expkey, u8 *out) +void aes_encrypt(u32 key_len, u8 *in, u8 *expkey, u8 *out) { u8 state[AES_STATECOLS * 4]; - u32 round; + u32 round, aes_rounds; + + aes_rounds = aes_get_rounds(key_len); memcpy(state, in, AES_STATECOLS * 4); add_round_key((u32 *)state, (u32 *)expkey); - for (round = 1; round < AES_ROUNDS + 1; round++) { - if (round < AES_ROUNDS) + for (round = 1; round < aes_rounds + 1; round++) { + if (round < aes_rounds) mix_sub_columns(state); else shift_rows(state); @@ -563,18 +592,20 @@ void aes_encrypt(u8 *in, u8 *expkey, u8 *out) memcpy(out, state, sizeof(state)); } -void aes_decrypt(u8 *in, u8 *expkey, u8 *out) +void aes_decrypt(u32 key_len, u8 *in, u8 *expkey, u8 *out) { u8 state[AES_STATECOLS * 4]; - int round; + int round, aes_rounds; + + aes_rounds = aes_get_rounds(key_len); memcpy(state, in, sizeof(state)); add_round_key((u32 *)state, - (u32 *)expkey + AES_ROUNDS * AES_STATECOLS); + (u32 *)expkey + aes_rounds * AES_STATECOLS); inv_shift_rows(state); - for (round = AES_ROUNDS; round--; ) { + for (round = aes_rounds; round--; ) { add_round_key((u32 *)state, (u32 *)expkey + round * AES_STATECOLS); if (round) @@ -600,7 +631,7 @@ void aes_apply_cbc_chain_data(u8 *cbc_chain_data, u8 *src, u8 *dst) *dst++ = *src++ ^ *cbc_chain_data++; } -void aes_cbc_encrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, +void aes_cbc_encrypt_blocks(u32 key_len, u8 *key_exp, u8 *iv, u8 *src, u8 *dst, u32 num_aes_blocks) { u8 tmp_data[AES_BLOCK_LENGTH]; @@ -616,7 +647,7 @@ void aes_cbc_encrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, debug_print_vector("AES Xor", AES_BLOCK_LENGTH, tmp_data); /* Encrypt the AES block */ - aes_encrypt(tmp_data, key_exp, dst); + aes_encrypt(key_len, tmp_data, key_exp, dst); debug_print_vector("AES Dst", AES_BLOCK_LENGTH, dst); /* Update pointers for next loop. */ @@ -626,7 +657,7 @@ void aes_cbc_encrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, } } -void aes_cbc_decrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, +void aes_cbc_decrypt_blocks(u32 key_len, u8 *key_exp, u8 *iv, u8 *src, u8 *dst, u32 num_aes_blocks) { u8 tmp_data[AES_BLOCK_LENGTH], tmp_block[AES_BLOCK_LENGTH]; @@ -642,7 +673,7 @@ void aes_cbc_decrypt_blocks(u8 *key_exp, u8 *iv, u8 *src, u8 *dst, memcpy(tmp_block, src, AES_BLOCK_LENGTH); /* Decrypt the AES block */ - aes_decrypt(src, key_exp, tmp_data); + aes_decrypt(key_len, src, key_exp, tmp_data); debug_print_vector("AES Xor", AES_BLOCK_LENGTH, tmp_data); /* Apply the chain data */ -- cgit v1.2.3