1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (c) 2012 The Chromium OS Authors. 4 */ 5 6 #ifndef _HASH_H 7 #define _HASH_H 8 9 #ifdef USE_HOSTCC 10 #include <linux/kconfig.h> 11 #endif 12 13 struct cmd_tbl; 14 15 /* 16 * Maximum digest size for all algorithms we support. Having this value 17 * avoids a malloc() or C99 local declaration in common/cmd_hash.c. 18 */ 19 #if CONFIG_IS_ENABLED(SHA384) || CONFIG_IS_ENABLED(SHA512) 20 #define HASH_MAX_DIGEST_SIZE 64 21 #else 22 #define HASH_MAX_DIGEST_SIZE 32 23 #endif 24 25 enum { 26 HASH_FLAG_VERIFY = 1 << 0, /* Enable verify mode */ 27 HASH_FLAG_ENV = 1 << 1, /* Allow env vars */ 28 }; 29 30 struct hash_algo { 31 const char *name; /* Name of algorithm */ 32 int digest_size; /* Length of digest */ 33 /** 34 * hash_func_ws: Generic hashing function 35 * 36 * This is the generic prototype for a hashing function. We only 37 * have the watchdog version at present. 38 * 39 * @input: Input buffer 40 * @ilen: Input buffer length 41 * @output: Checksum result (length depends on algorithm) 42 * @chunk_sz: Trigger watchdog after processing this many bytes 43 */ 44 void (*hash_func_ws)(const unsigned char *input, unsigned int ilen, 45 unsigned char *output, unsigned int chunk_sz); 46 int chunk_size; /* Watchdog chunk size */ 47 /* 48 * hash_init: Create the context for progressive hashing 49 * 50 * @algo: Pointer to the hash_algo struct 51 * @ctxp: Pointer to the pointer of the context for hashing 52 * @return 0 if ok, -1 on error 53 */ 54 int (*hash_init)(struct hash_algo *algo, void **ctxp); 55 /* 56 * hash_update: Perform hashing on the given buffer 57 * 58 * The context is freed by this function if an error occurs. 59 * 60 * @algo: Pointer to the hash_algo struct 61 * @ctx: Pointer to the context for hashing 62 * @buf: Pointer to the buffer being hashed 63 * @size: Size of the buffer being hashed 64 * @is_last: 1 if this is the last update; 0 otherwise 65 * @return 0 if ok, -1 on error 66 */ 67 int (*hash_update)(struct hash_algo *algo, void *ctx, const void *buf, 68 unsigned int size, int is_last); 69 /* 70 * hash_finish: Write the hash result to the given buffer 71 * 72 * The context is freed by this function. 73 * 74 * @algo: Pointer to the hash_algo struct 75 * @ctx: Pointer to the context for hashing 76 * @dest_buf: Pointer to the buffer for the result 77 * @size: Size of the buffer for the result 78 * @return 0 if ok, -ENOSPC if size of the result buffer is too small 79 * or -1 on other errors 80 */ 81 int (*hash_finish)(struct hash_algo *algo, void *ctx, void *dest_buf, 82 int size); 83 }; 84 85 #ifndef USE_HOSTCC 86 /** 87 * hash_command: Process a hash command for a particular algorithm 88 * 89 * This common function is used to implement specific hash commands. 90 * 91 * @algo_name: Hash algorithm being used (lower case!) 92 * @flags: Flags value (HASH_FLAG_...) 93 * @cmdtp: Pointer to command table entry 94 * @flag: Some flags normally 0 (see CMD_FLAG_.. above) 95 * @argc: Number of arguments (arg 0 must be the command text) 96 * @argv: Arguments 97 */ 98 int hash_command(const char *algo_name, int flags, struct cmd_tbl *cmdtp, 99 int flag, int argc, char *const argv[]); 100 101 /** 102 * hash_block() - Hash a block according to the requested algorithm 103 * 104 * The caller probably knows the hash length for the chosen algorithm, but 105 * in order to provide a general interface, and output_size parameter is 106 * provided. 107 * 108 * @algo_name: Hash algorithm to use 109 * @data: Data to hash 110 * @len: Lengh of data to hash in bytes 111 * @output: Place to put hash value 112 * @output_size: On entry, pointer to the number of bytes available in 113 * output. On exit, pointer to the number of bytes used. 114 * If NULL, then it is assumed that the caller has 115 * allocated enough space for the hash. This is possible 116 * since the caller is selecting the algorithm. 117 * @return 0 if ok, -ve on error: -EPROTONOSUPPORT for an unknown algorithm, 118 * -ENOSPC if the output buffer is not large enough. 119 */ 120 int hash_block(const char *algo_name, const void *data, unsigned int len, 121 uint8_t *output, int *output_size); 122 123 #endif /* !USE_HOSTCC */ 124 125 /** 126 * hash_lookup_algo() - Look up the hash_algo struct for an algorithm 127 * 128 * The function returns the pointer to the struct or -EPROTONOSUPPORT if the 129 * algorithm is not available. 130 * 131 * @algo_name: Hash algorithm to look up 132 * @algop: Pointer to the hash_algo struct if found 133 * 134 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 135 */ 136 int hash_lookup_algo(const char *algo_name, struct hash_algo **algop); 137 138 /** 139 * hash_progressive_lookup_algo() - Look up hash_algo for prog. hash support 140 * 141 * The function returns the pointer to the struct or -EPROTONOSUPPORT if the 142 * algorithm is not available with progressive hash support. 143 * 144 * @algo_name: Hash algorithm to look up 145 * @algop: Pointer to the hash_algo struct if found 146 * 147 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 148 */ 149 int hash_progressive_lookup_algo(const char *algo_name, 150 struct hash_algo **algop); 151 152 /** 153 * hash_parse_string() - Parse hash string into a binary array 154 * 155 * The function parses a hash string into a binary array that 156 * can for example easily be used to compare to hash values. 157 * 158 * @algo_name: Hash algorithm to look up 159 * @str: Hash string to get parsed 160 * @result: Binary array of the parsed hash string 161 * 162 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 163 */ 164 int hash_parse_string(const char *algo_name, const char *str, uint8_t *result); 165 166 #endif 167