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 <aes.h> 13 #include <malloc.h> 14 #include <asm/byteorder.h> 15 #include <linux/compiler.h> 16 17 DECLARE_GLOBAL_DATA_PTR; 18 19 /** 20 * do_aes() - Handle the "aes" command-line command 21 * @cmdtp: Command data struct pointer 22 * @flag: Command flag 23 * @argc: Command-line argument count 24 * @argv: Array of command-line arguments 25 * 26 * Returns zero on success, CMD_RET_USAGE in case of misuse and negative 27 * on error. 28 */ 29 static int do_aes(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]) 30 { 31 uint32_t key_addr, src_addr, dst_addr, len; 32 uint8_t *key_ptr, *src_ptr, *dst_ptr; 33 uint8_t key_exp[AES_EXPAND_KEY_LENGTH]; 34 uint32_t aes_blocks; 35 int enc; 36 37 if (argc != 6) 38 return CMD_RET_USAGE; 39 40 if (!strncmp(argv[1], "enc", 3)) 41 enc = 1; 42 else if (!strncmp(argv[1], "dec", 3)) 43 enc = 0; 44 else 45 return CMD_RET_USAGE; 46 47 key_addr = simple_strtoul(argv[2], NULL, 16); 48 src_addr = simple_strtoul(argv[3], NULL, 16); 49 dst_addr = simple_strtoul(argv[4], NULL, 16); 50 len = simple_strtoul(argv[5], NULL, 16); 51 52 key_ptr = (uint8_t *)key_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, src_ptr, dst_ptr, aes_blocks); 64 else 65 aes_cbc_decrypt_blocks(key_exp, src_ptr, dst_ptr, aes_blocks); 66 67 return 0; 68 } 69 70 /***************************************************/ 71 #ifdef CONFIG_SYS_LONGHELP 72 static char aes_help_text[] = 73 "enc key src dst len - Encrypt block of data $len bytes long\n" 74 " at address $src using a key at address\n" 75 " $key and store the result at address\n" 76 " $dst. The $len size must be multiple of\n" 77 " 16 bytes and $key must be 16 bytes long.\n" 78 "aes dec key src dst len - Decrypt block of data $len bytes long\n" 79 " at address $src using a key at address\n" 80 " $key and store the result at address\n" 81 " $dst. The $len size must be multiple of\n" 82 " 16 bytes and $key must be 16 bytes long."; 83 #endif 84 85 U_BOOT_CMD( 86 aes, 6, 1, do_aes, 87 "AES 128 CBC encryption", 88 aes_help_text 89 ); 90