You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

93 lines
3.8 KiB

4 years ago
#ifndef _KHASH_H
#define _KHASH_H
#ifdef __cplusplus
extern "C" {
#endif
#include <stdint.h>
#ifdef __GNUC__
#define _deprecated(x) __attribute__((deprecated))
#else
#define _deprecated(x)
#endif
#define KHASH_ALGO_DEFAULT ((uint8_t)0)
#define KHASH_ALGO_CRC32 ((uint8_t)1)
#define KHASH_ALGO_CRC64 ((uint8_t)2)
#define KHASH_ALGO_SHA256 ((uint8_t)3)
#define KHASH_ALGO_SHA256_TRUNCATED ((uint8_t)4) /* SHA256 truncated to 64 bits */
4 years ago
/// No salt
#define KHASH_SALT_TYPE_NONE ((uint8_t)0)
/// The default static salt
#define KHASH_SALT_TYPE_DEFAULT ((uint8_t)1)
/// A specific salt passed as `data` to `khash_new_salt`.
#define KHASH_SALT_TYPE_SPECIFIC ((uint8_t)2)
/// A randomly generated salt.
#define KHASH_SALT_TYPE_RANDOM ((uint8_t)3)
/// A valid salt for khash functions. Instantiated with `khash_new_salt`.
4 years ago
typedef struct {
uint8_t salt_type;
uint32_t size;
uint8_t* body;
} khash_salt;
4 years ago
/// A valid context for khash functinos. Instantiated with `khash_new_context`.
typedef struct {
uint8_t algo;
uint64_t flags;
khash_salt salt;
} khash_ctx;
4 years ago
/// Returned by all functions that succeed.
#define KHASH_SUCCESS ((int32_t)0)
/// Reading into the hash failed
#define KHASH_ERROR_IO ((int32_t)1)
/// Formatting the has failed
#define KHASH_ERROR_FORMAT ((int32_t)2)
/// Bad hash length
#define KHASH_ERROR_LENGTH ((int32_t)3)
/// Random number generation failed
#define KHASH_ERROR_RNG ((int32_t)4)
/// Unknown error
#define KHASH_ERROR_UNKNOWN ((int32_t)-1)
/// Find the maximum possible digest output size for the given algorithm and input length, and set that to `digest_length`. If the algorithm's output is not dynamically sized `input_length` does not need to be provided.
extern int32_t khash_max_length(uint8_t algo, size_t input_length, size_t* digest_length);
/// Create a new context with the specified algorithm (one of the `KHASH_ALGO_*` macro constants), salt type (one of the `KHASH_SALT_TYPE_*` constants), optional salt `data` and salt length `size`, and output pointer `output`.
/// `data` may be `NULL` if the corresponding `salt_type` does not require an input.
extern int32_t khash_new_context(uint8_t algo, uint8_t salt_type, const void* data, size_t size, khash_ctx* output);
/// Free a `khash_ctx` allocated with `khash_new_context`.
extern int32_t khash_free_context(khash_ctx* ctx);
/// Clone a `khash_ctx` allocated with `khash_new_context`. The clone is a newly allocated instance.
extern int32_t khash_clone_context(const khash_ctx* src, khash_ctx* dst);
4 years ago
/// Compute the length of hash required for the specified input.
/// This function does not free `context` after it has been called.
extern int32_t khash_length(const khash_ctx* context, const void* data, size_t size, size_t* length);
4 years ago
/// Compute the hash and store it in `string`. Will write no more than `strlen` bytes into `string`.
/// This function takes ownership of and frees `context` after it has been called.
extern int32_t khash_do(khash_ctx* context, const void* data, size_t size, char* string, size_t strlen);
4 years ago
/// Create a new salt. `salt_type` is expected to be one of the above defined `KHASH_SALT_TYPE_*` macros.
/// Depending on the type, `data` may be `NULL`.
extern int32_t khash_new_salt(uint8_t salt_type, const void* data, size_t size, khash_salt* output) _deprecated("Use `khash_new_context` instead.");
/// Free a salt allocated with `khash_new_salt`. It is okay to call this multiple times.
extern int32_t khash_free_salt(khash_salt* salt) _deprecated("Use `khash_free_context` instead.");
/// Clone a salt allocated with `khash_new_salt`.
extern int32_t khash_clone_salt(const khash_salt* src, khash_salt* dst) _deprecated("Use `khash_close_context` instead.");
4 years ago
#ifdef __cplusplus
}
#endif
4 years ago
#undef _deprecated
4 years ago
#endif /* _KHASH_H */