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 struct cmd_tbl; 10 11 /* 12 * Maximum digest size for all algorithms we support. Having this value 13 * avoids a malloc() or C99 local declaration in common/cmd_hash.c. 14 */ 15 #if defined(CONFIG_SHA384) || defined(CONFIG_SHA512) 16 #define HASH_MAX_DIGEST_SIZE 64 17 #else 18 #define HASH_MAX_DIGEST_SIZE 32 19 #endif 20 21 enum { 22 HASH_FLAG_VERIFY = 1 << 0, /* Enable verify mode */ 23 HASH_FLAG_ENV = 1 << 1, /* Allow env vars */ 24 }; 25 26 struct hash_algo { 27 const char *name; /* Name of algorithm */ 28 int digest_size; /* Length of digest */ 29 /** 30 * hash_func_ws: Generic hashing function 31 * 32 * This is the generic prototype for a hashing function. We only 33 * have the watchdog version at present. 34 * 35 * @input: Input buffer 36 * @ilen: Input buffer length 37 * @output: Checksum result (length depends on algorithm) 38 * @chunk_sz: Trigger watchdog after processing this many bytes 39 */ 40 void (*hash_func_ws)(const unsigned char *input, unsigned int ilen, 41 unsigned char *output, unsigned int chunk_sz); 42 int chunk_size; /* Watchdog chunk size */ 43 /* 44 * hash_init: Create the context for progressive hashing 45 * 46 * @algo: Pointer to the hash_algo struct 47 * @ctxp: Pointer to the pointer of the context for hashing 48 * @return 0 if ok, -1 on error 49 */ 50 int (*hash_init)(struct hash_algo *algo, void **ctxp); 51 /* 52 * hash_update: Perform hashing on the given buffer 53 * 54 * The context is freed by this function if an error occurs. 55 * 56 * @algo: Pointer to the hash_algo struct 57 * @ctx: Pointer to the context for hashing 58 * @buf: Pointer to the buffer being hashed 59 * @size: Size of the buffer being hashed 60 * @is_last: 1 if this is the last update; 0 otherwise 61 * @return 0 if ok, -1 on error 62 */ 63 int (*hash_update)(struct hash_algo *algo, void *ctx, const void *buf, 64 unsigned int size, int is_last); 65 /* 66 * hash_finish: Write the hash result to the given buffer 67 * 68 * The context is freed by this function. 69 * 70 * @algo: Pointer to the hash_algo struct 71 * @ctx: Pointer to the context for hashing 72 * @dest_buf: Pointer to the buffer for the result 73 * @size: Size of the buffer for the result 74 * @return 0 if ok, -ENOSPC if size of the result buffer is too small 75 * or -1 on other errors 76 */ 77 int (*hash_finish)(struct hash_algo *algo, void *ctx, void *dest_buf, 78 int size); 79 }; 80 81 #ifndef USE_HOSTCC 82 /** 83 * hash_command: Process a hash command for a particular algorithm 84 * 85 * This common function is used to implement specific hash commands. 86 * 87 * @algo_name: Hash algorithm being used (lower case!) 88 * @flags: Flags value (HASH_FLAG_...) 89 * @cmdtp: Pointer to command table entry 90 * @flag: Some flags normally 0 (see CMD_FLAG_.. above) 91 * @argc: Number of arguments (arg 0 must be the command text) 92 * @argv: Arguments 93 */ 94 int hash_command(const char *algo_name, int flags, struct cmd_tbl *cmdtp, 95 int flag, int argc, char *const argv[]); 96 97 /** 98 * hash_block() - Hash a block according to the requested algorithm 99 * 100 * The caller probably knows the hash length for the chosen algorithm, but 101 * in order to provide a general interface, and output_size parameter is 102 * provided. 103 * 104 * @algo_name: Hash algorithm to use 105 * @data: Data to hash 106 * @len: Lengh of data to hash in bytes 107 * @output: Place to put hash value 108 * @output_size: On entry, pointer to the number of bytes available in 109 * output. On exit, pointer to the number of bytes used. 110 * If NULL, then it is assumed that the caller has 111 * allocated enough space for the hash. This is possible 112 * since the caller is selecting the algorithm. 113 * @return 0 if ok, -ve on error: -EPROTONOSUPPORT for an unknown algorithm, 114 * -ENOSPC if the output buffer is not large enough. 115 */ 116 int hash_block(const char *algo_name, const void *data, unsigned int len, 117 uint8_t *output, int *output_size); 118 119 #endif /* !USE_HOSTCC */ 120 121 /** 122 * hash_lookup_algo() - Look up the hash_algo struct for an algorithm 123 * 124 * The function returns the pointer to the struct or -EPROTONOSUPPORT if the 125 * algorithm is not available. 126 * 127 * @algo_name: Hash algorithm to look up 128 * @algop: Pointer to the hash_algo struct if found 129 * 130 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 131 */ 132 int hash_lookup_algo(const char *algo_name, struct hash_algo **algop); 133 134 /** 135 * hash_progressive_lookup_algo() - Look up hash_algo for prog. hash support 136 * 137 * The function returns the pointer to the struct or -EPROTONOSUPPORT if the 138 * algorithm is not available with progressive hash support. 139 * 140 * @algo_name: Hash algorithm to look up 141 * @algop: Pointer to the hash_algo struct if found 142 * 143 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 144 */ 145 int hash_progressive_lookup_algo(const char *algo_name, 146 struct hash_algo **algop); 147 148 /** 149 * hash_parse_string() - Parse hash string into a binary array 150 * 151 * The function parses a hash string into a binary array that 152 * can for example easily be used to compare to hash values. 153 * 154 * @algo_name: Hash algorithm to look up 155 * @str: Hash string to get parsed 156 * @result: Binary array of the parsed hash string 157 * 158 * @return 0 if ok, -EPROTONOSUPPORT for an unknown algorithm. 159 */ 160 int hash_parse_string(const char *algo_name, const char *str, uint8_t *result); 161 162 #endif 163