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