hash.h 5.3 KB

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  1. /* SPDX-License-Identifier: GPL-2.0+ */
  2. /*
  3. * Copyright (c) 2012 The Chromium OS Authors.
  4. */
  5. #ifndef _HASH_H
  6. #define _HASH_H
  7. #ifdef USE_HOSTCC
  8. #include <linux/kconfig.h>
  9. #endif
  10. struct cmd_tbl;
  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 CONFIG_IS_ENABLED(SHA384) || CONFIG_IS_ENABLED(SHA512)
  16. #define HASH_MAX_DIGEST_SIZE 64
  17. #else
  18. #define HASH_MAX_DIGEST_SIZE 32
  19. #endif
  20. enum {
  21. HASH_FLAG_VERIFY = 1 << 0, /* Enable verify mode */
  22. HASH_FLAG_ENV = 1 << 1, /* Allow env vars */
  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. #ifndef USE_HOSTCC
  79. /**
  80. * hash_command: Process a hash command for a particular algorithm
  81. *
  82. * This common function is used to implement specific hash commands.
  83. *
  84. * @algo_name: Hash algorithm being used (lower case!)
  85. * @flags: Flags value (HASH_FLAG_...)
  86. * @cmdtp: Pointer to command table entry
  87. * @flag: Some flags normally 0 (see CMD_FLAG_.. above)
  88. * @argc: Number of arguments (arg 0 must be the command text)
  89. * @argv: Arguments
  90. */
  91. int hash_command(const char *algo_name, int flags, struct cmd_tbl *cmdtp,
  92. int flag, int argc, char *const argv[]);
  93. /**
  94. * hash_block() - Hash a block according to the requested algorithm
  95. *
  96. * The caller probably knows the hash length for the chosen algorithm, but
  97. * in order to provide a general interface, and output_size parameter is
  98. * provided.
  99. *
  100. * @algo_name: Hash algorithm to use
  101. * @data: Data to hash
  102. * @len: Lengh of data to hash in bytes
  103. * @output: Place to put hash value
  104. * @output_size: On entry, pointer to the number of bytes available in
  105. * output. On exit, pointer to the number of bytes used.
  106. * If NULL, then it is assumed that the caller has
  107. * allocated enough space for the hash. This is possible
  108. * since the caller is selecting the algorithm.
  109. * Return: 0 if ok, -ve on error: -EPROTONOSUPPORT for an unknown algorithm,
  110. * -ENOSPC if the output buffer is not large enough.
  111. */
  112. int hash_block(const char *algo_name, const void *data, unsigned int len,
  113. uint8_t *output, int *output_size);
  114. #endif /* !USE_HOSTCC */
  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. * hash_progressive_lookup_algo() - Look up hash_algo for prog. hash support
  129. *
  130. * The function returns the pointer to the struct or -EPROTONOSUPPORT if the
  131. * algorithm is not available with progressive hash support.
  132. *
  133. * @algo_name: Hash algorithm to look up
  134. * @algop: Pointer to the hash_algo struct if found
  135. *
  136. * Return: 0 if ok, -EPROTONOSUPPORT for an unknown algorithm.
  137. */
  138. int hash_progressive_lookup_algo(const char *algo_name,
  139. struct hash_algo **algop);
  140. /**
  141. * hash_parse_string() - Parse hash string into a binary array
  142. *
  143. * The function parses a hash string into a binary array that
  144. * can for example easily be used to compare to hash values.
  145. *
  146. * @algo_name: Hash algorithm to look up
  147. * @str: Hash string to get parsed
  148. * @result: Binary array of the parsed hash string
  149. *
  150. * Return: 0 if ok, -EPROTONOSUPPORT for an unknown algorithm.
  151. */
  152. int hash_parse_string(const char *algo_name, const char *str, uint8_t *result);
  153. #endif