1 /* 2 * Copyright (c) 2012 The Chromium OS Authors. 3 * See file CREDITS for list of people who contributed to this 4 * project. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 19 * MA 02111-1307 USA 20 */ 21 22 #ifndef _HASH_H 23 #define _HASH_H 24 25 #if defined(CONFIG_SHA1SUM_VERIFY) || defined(CONFIG_CRC32_VERIFY) 26 #define CONFIG_HASH_VERIFY 27 #endif 28 29 struct hash_algo { 30 const char *name; /* Name of algorithm */ 31 int digest_size; /* Length of digest */ 32 /** 33 * hash_func_ws: Generic hashing function 34 * 35 * This is the generic prototype for a hashing function. We only 36 * have the watchdog version at present. 37 * 38 * @input: Input buffer 39 * @ilen: Input buffer length 40 * @output: Checksum result (length depends on algorithm) 41 * @chunk_sz: Trigger watchdog after processing this many bytes 42 */ 43 void (*hash_func_ws)(const unsigned char *input, unsigned int ilen, 44 unsigned char *output, unsigned int chunk_sz); 45 int chunk_size; /* Watchdog chunk size */ 46 }; 47 48 /* 49 * Maximum digest size for all algorithms we support. Having this value 50 * avoids a malloc() or C99 local declaration in common/cmd_hash.c. 51 */ 52 #define HASH_MAX_DIGEST_SIZE 32 53 54 enum { 55 HASH_FLAG_VERIFY = 1 << 0, /* Enable verify mode */ 56 HASH_FLAG_ENV = 1 << 1, /* Allow env vars */ 57 }; 58 59 /** 60 * hash_command: Process a hash command for a particular algorithm 61 * 62 * This common function is used to implement specific hash commands. 63 * 64 * @algo_name: Hash algorithm being used (lower case!) 65 * @flags: Flags value (HASH_FLAG_...) 66 * @cmdtp: Pointer to command table entry 67 * @flag: Some flags normally 0 (see CMD_FLAG_.. above) 68 * @argc: Number of arguments (arg 0 must be the command text) 69 * @argv: Arguments 70 */ 71 int hash_command(const char *algo_name, int flags, cmd_tbl_t *cmdtp, int flag, 72 int argc, char * const argv[]); 73 74 /** 75 * hash_block() - Hash a block according to the requested algorithm 76 * 77 * The caller probably knows the hash length for the chosen algorithm, but 78 * in order to provide a general interface, and output_size parameter is 79 * provided. 80 * 81 * @algo_name: Hash algorithm to use 82 * @data: Data to hash 83 * @len: Lengh of data to hash in bytes 84 * @output: Place to put hash value 85 * @output_size: On entry, pointer to the number of bytes available in 86 * output. On exit, pointer to the number of bytes used. 87 * If NULL, then it is assumed that the caller has 88 * allocated enough space for the hash. This is possible 89 * since the caller is selecting the algorithm. 90 * @return 0 if ok, -ve on error: -EPROTONOSUPPORT for an unknown algorithm, 91 * -ENOSPC if the output buffer is not large enough. 92 */ 93 int hash_block(const char *algo_name, const void *data, unsigned int len, 94 uint8_t *output, int *output_size); 95 96 #endif 97