1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2014 Marek Vasut <marex@denx.de>
4 *
5 * Command for en/de-crypting block of memory with AES-128-CBC cipher.
6 */
7
8 #include <common.h>
9 #include <command.h>
10 #include <environment.h>
11 #include <uboot_aes.h>
12 #include <malloc.h>
13 #include <asm/byteorder.h>
14 #include <linux/compiler.h>
15
16 /**
17 * do_aes() - Handle the "aes" command-line command
18 * @cmdtp: Command data struct pointer
19 * @flag: Command flag
20 * @argc: Command-line argument count
21 * @argv: Array of command-line arguments
22 *
23 * Returns zero on success, CMD_RET_USAGE in case of misuse and negative
24 * on error.
25 */
do_aes(cmd_tbl_t * cmdtp,int flag,int argc,char * const argv[])26 static int do_aes(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
27 {
28 uint32_t key_addr, iv_addr, src_addr, dst_addr, len;
29 uint8_t *key_ptr, *iv_ptr, *src_ptr, *dst_ptr;
30 uint8_t key_exp[AES_EXPAND_KEY_LENGTH];
31 uint32_t aes_blocks;
32 int enc;
33
34 if (argc != 7)
35 return CMD_RET_USAGE;
36
37 if (!strncmp(argv[1], "enc", 3))
38 enc = 1;
39 else if (!strncmp(argv[1], "dec", 3))
40 enc = 0;
41 else
42 return CMD_RET_USAGE;
43
44 key_addr = simple_strtoul(argv[2], NULL, 16);
45 iv_addr = simple_strtoul(argv[3], NULL, 16);
46 src_addr = simple_strtoul(argv[4], NULL, 16);
47 dst_addr = simple_strtoul(argv[5], NULL, 16);
48 len = simple_strtoul(argv[6], NULL, 16);
49
50 key_ptr = (uint8_t *)key_addr;
51 iv_ptr = (uint8_t *)iv_addr;
52 src_ptr = (uint8_t *)src_addr;
53 dst_ptr = (uint8_t *)dst_addr;
54
55 /* First we expand the key. */
56 aes_expand_key(key_ptr, key_exp);
57
58 /* Calculate the number of AES blocks to encrypt. */
59 aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH);
60
61 if (enc)
62 aes_cbc_encrypt_blocks(key_exp, iv_ptr, src_ptr, dst_ptr,
63 aes_blocks);
64 else
65 aes_cbc_decrypt_blocks(key_exp, iv_ptr, src_ptr, dst_ptr,
66 aes_blocks);
67
68 return 0;
69 }
70
71 /***************************************************/
72 #ifdef CONFIG_SYS_LONGHELP
73 static char aes_help_text[] =
74 "enc key iv src dst len - Encrypt block of data $len bytes long\n"
75 " at address $src using a key at address\n"
76 " $key with initialization vector at address\n"
77 " $iv. Store the result at address $dst.\n"
78 " The $len size must be multiple of 16 bytes.\n"
79 " The $key and $iv must be 16 bytes long.\n"
80 "aes dec key iv src dst len - Decrypt block of data $len bytes long\n"
81 " at address $src using a key at address\n"
82 " $key with initialization vector at address\n"
83 " $iv. Store the result at address $dst.\n"
84 " The $len size must be multiple of 16 bytes.\n"
85 " The $key and $iv must be 16 bytes long.";
86 #endif
87
88 U_BOOT_CMD(
89 aes, 7, 1, do_aes,
90 "AES 128 CBC encryption",
91 aes_help_text
92 );
93