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Diffstat (limited to 'board/nvidia/common/crypto/crypto.c')
| -rwxr-xr-x | board/nvidia/common/crypto/crypto.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/board/nvidia/common/crypto/crypto.c b/board/nvidia/common/crypto/crypto.c new file mode 100755 index 00000000000..9cfcd5de10e --- /dev/null +++ b/board/nvidia/common/crypto/crypto.c @@ -0,0 +1,236 @@ +/* + * (C) Copyright 2010 - 2011 + * NVIDIA Corporation <www.nvidia.com> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <asm/errno.h> +#include "crypto.h" +#include "aes_ref.h" + +static u8 zero_key[16]; + +#ifdef DEBUG +static void debug_print_vector(char *name, u32 num_bytes, u8 *data) +{ + u32 i; + + printf("%s [%d] @0x%08x", name, num_bytes, (u32)data); + for (i = 0; i < num_bytes; i++) { + if (i % 16 == 0) + printf(" = "); + printf("%02x", data[i]); + if ((i+1) % 16 != 0) + printf(" "); + } + printf("\n"); +} +#else +#define debug_print_vector(name, num_bytes, data) +#endif + +static void apply_cbc_chain_data(u8 *cbc_chain_data, u8 *src, u8 *dst) +{ + int i; + + for (i = 0; i < 16; i++) + *dst++ = *src++ ^ *cbc_chain_data++; +} + +static int determine_crypto_ops(enum security_mode security, int *encrypt, + int *sign) +{ + int err = 0; + + switch (security) { + case SECURITY_MODE_PLAINTEXT: + *encrypt = 0; + *sign = 0; + break; + + case SECURITY_MODE_CHECKSUM: + *encrypt = 0; + *sign = 1; + break; + + case SECURITY_MODE_ENCRYPTED: + *encrypt = 1; + *sign = 1; + break; + + default: + printf("determine_crypto_ops: security mode not set.\n"); + err = -EINVAL; + } + + return err; +} + +static void generate_key_schedule(u8 *key, u8 *key_schedule, int encrypt_data) +{ + /* Expand the key to produce a key schedule. */ + if (encrypt_data) + /* Expand the provided key. */ + aes_expand_key(key, key_schedule); + else + /* + * The only need for a key is for signing/checksum purposes, so + * expand a key of 0's. + */ + aes_expand_key(zero_key, key_schedule); +} + +static void encrypt_object(u8 *key_schedule, u8 *src, u8 *dst, + u32 num_aes_blocks) +{ + u32 i; + u8 *cbc_chain_data; + u8 tmp_data[KEY_LENGTH]; + + cbc_chain_data = zero_key; /* Convenient array of 0's for IV */ + + 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", KEY_LENGTH, src); + + /* Apply the chain data */ + apply_cbc_chain_data(cbc_chain_data, src, tmp_data); + debug_print_vector("AES Xor", KEY_LENGTH, tmp_data); + + /* encrypt the AES block */ + aes_encrypt(tmp_data, key_schedule, dst); + debug_print_vector("AES Dst", KEY_LENGTH, dst); + + /* Update pointers for next loop. */ + cbc_chain_data = dst; + src += KEY_LENGTH; + dst += KEY_LENGTH; + } +} + +static void left_shift_vector(u8 *in, u8 *out, u32 size) +{ + s32 i; + u8 carry = 0; + + for (i = size - 1; i >= 0; i--) { + out[i] = (in[i] << 1) | carry; + carry = in[i] >> 7; /* get most significant bit */ + } +} + +static void sign_object(u8 *key, u8 *key_schedule, u8 *src, u8 *dst, + u32 num_aes_blocks) +{ + u32 i; + u8 *cbc_chain_data; + + u8 L[KEY_LENGTH]; + u8 K1[KEY_LENGTH]; + u8 tmp_data[KEY_LENGTH]; + + cbc_chain_data = zero_key; /* Convenient array of 0's for IV */ + + /* compute K1 constant needed by AES-CMAC calculation */ + for (i = 0; i < KEY_LENGTH; i++) + tmp_data[i] = 0; + + encrypt_object(key_schedule, tmp_data, L, 1); + debug_print_vector("AES(key, nonce)", KEY_LENGTH, L); + + left_shift_vector(L, K1, sizeof(L)); + debug_print_vector("L", KEY_LENGTH, L); + + if ((L[0] >> 7) != 0) /* get MSB of L */ + K1[KEY_LENGTH-1] ^= AES_CMAC_CONST_RB; + debug_print_vector("K1", KEY_LENGTH, K1); + + /* compute the AES-CMAC value */ + for (i = 0; i < num_aes_blocks; i++) { + /* Apply the chain data */ + apply_cbc_chain_data(cbc_chain_data, src, tmp_data); + + /* for the final block, XOR K1 into the IV */ + if (i == num_aes_blocks-1) + apply_cbc_chain_data(tmp_data, K1, tmp_data); + + /* encrypt the AES block */ + aes_encrypt(tmp_data, key_schedule, (u8 *)dst); + + debug("sign_obj: block %d of %d\n", i, num_aes_blocks); + debug_print_vector("AES-CMAC Src", KEY_LENGTH, src); + debug_print_vector("AES-CMAC Xor", KEY_LENGTH, tmp_data); + debug_print_vector("AES-CMAC Dst", KEY_LENGTH, (u8 *)dst); + + /* Update pointers for next loop. */ + cbc_chain_data = (u8 *)dst; + src += KEY_LENGTH; + } + + debug_print_vector("AES-CMAC Hash", KEY_LENGTH, (u8 *)dst); +} + +static int encrypt_and_sign(u8 *key, enum security_mode security, u8 *src, + u32 length, u8 *sig_dst) +{ + int encrypt_data; + int sign_data; + u32 num_aes_blocks; + u8 key_schedule[4 * AES_STATECOLS * (AES_ROUNDS+1)]; + int err; + + err = determine_crypto_ops(security, &encrypt_data, &sign_data); + if (err) + return err; + + debug("encrypt_and_sign: Length = %d\n", length); + debug_print_vector("AES key", KEY_LENGTH, key); + + generate_key_schedule(key, key_schedule, encrypt_data); + + num_aes_blocks = ICEIL(length, KEY_LENGTH); + + if (encrypt_data) { + debug("encrypt_and_sign: begin encryption\n"); + + /* Perform this in place, resulting in src being encrypted. */ + encrypt_object(key_schedule, src, src, num_aes_blocks); + + debug("encrypt_and_sign: end encryption\n"); + } + + if (sign_data) { + debug("encrypt_and_sign: begin signing\n"); + + /* encrypt the data, overwriting the result in signature. */ + sign_object(key, key_schedule, src, sig_dst, num_aes_blocks); + + debug("encrypt_and_sign: end signing\n"); + } + + return err; +} + +int sign_data_block(u8 *source, u32 length, u8 *signature) +{ + return encrypt_and_sign(zero_key, SECURITY_MODE_CHECKSUM, source, + length, signature); +} |