1 /* 2 * Copyright (C) 2014 Marek Vasut <marex@denx.de> 3 * 4 * Command for en/de-crypting block of memory with AES-128-CBC cipher. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <command.h> 11 #include <environment.h> 12 #include <uboot_aes.h> 13 #include <malloc.h> 14 #include <asm/byteorder.h> 15 #include <linux/compiler.h> 16 17 /** 18 * do_aes() - Handle the "aes" command-line command 19 * @cmdtp: Command data struct pointer 20 * @flag: Command flag 21 * @argc: Command-line argument count 22 * @argv: Array of command-line arguments 23 * 24 * Returns zero on success, CMD_RET_USAGE in case of misuse and negative 25 * on error. 26 */ 27 static int do_aes(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]) 28 { 29 uint32_t key_addr, iv_addr, src_addr, dst_addr, len; 30 uint8_t *key_ptr, *iv_ptr, *src_ptr, *dst_ptr; 31 uint8_t key_exp[AES_EXPAND_KEY_LENGTH]; 32 uint32_t aes_blocks; 33 int enc; 34 35 if (argc != 7) 36 return CMD_RET_USAGE; 37 38 if (!strncmp(argv[1], "enc", 3)) 39 enc = 1; 40 else if (!strncmp(argv[1], "dec", 3)) 41 enc = 0; 42 else 43 return CMD_RET_USAGE; 44 45 key_addr = simple_strtoul(argv[2], NULL, 16); 46 iv_addr = simple_strtoul(argv[3], NULL, 16); 47 src_addr = simple_strtoul(argv[4], NULL, 16); 48 dst_addr = simple_strtoul(argv[5], NULL, 16); 49 len = simple_strtoul(argv[6], NULL, 16); 50 51 key_ptr = (uint8_t *)key_addr; 52 iv_ptr = (uint8_t *)iv_addr; 53 src_ptr = (uint8_t *)src_addr; 54 dst_ptr = (uint8_t *)dst_addr; 55 56 /* First we expand the key. */ 57 aes_expand_key(key_ptr, key_exp); 58 59 /* Calculate the number of AES blocks to encrypt. */ 60 aes_blocks = DIV_ROUND_UP(len, AES_KEY_LENGTH); 61 62 if (enc) 63 aes_cbc_encrypt_blocks(key_exp, iv_ptr, src_ptr, dst_ptr, 64 aes_blocks); 65 else 66 aes_cbc_decrypt_blocks(key_exp, iv_ptr, src_ptr, dst_ptr, 67 aes_blocks); 68 69 return 0; 70 } 71 72 /***************************************************/ 73 #ifdef CONFIG_SYS_LONGHELP 74 static char aes_help_text[] = 75 "enc key iv src dst len - Encrypt block of data $len bytes long\n" 76 " at address $src using a key at address\n" 77 " $key with initialization vector at address\n" 78 " $iv. Store the result at address $dst.\n" 79 " The $len size must be multiple of 16 bytes.\n" 80 " The $key and $iv must be 16 bytes long.\n" 81 "aes dec key iv src dst len - Decrypt block of data $len bytes long\n" 82 " at address $src using a key at address\n" 83 " $key with initialization vector at address\n" 84 " $iv. Store the result at address $dst.\n" 85 " The $len size must be multiple of 16 bytes.\n" 86 " The $key and $iv must be 16 bytes long."; 87 #endif 88 89 U_BOOT_CMD( 90 aes, 7, 1, do_aes, 91 "AES 128 CBC encryption", 92 aes_help_text 93 ); 94