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