postgresql/src/include/common/checksum_helper.h

73 lines
2.0 KiB
C

/*-------------------------------------------------------------------------
*
* checksum_helper.h
* Compute a checksum of any of various types using common routines
*
* Portions Copyright (c) 2016-2024, PostgreSQL Global Development Group
*
* IDENTIFICATION
* src/include/common/checksum_helper.h
*
*-------------------------------------------------------------------------
*/
#ifndef CHECKSUM_HELPER_H
#define CHECKSUM_HELPER_H
#include "common/cryptohash.h"
#include "common/sha2.h"
#include "port/pg_crc32c.h"
/*
* Supported checksum types. It's not necessarily the case that code using
* these functions needs a cryptographically strong checksum; it may only
* need to detect accidental modification. That's why we include CRC-32C: it's
* much faster than any of the other algorithms. On the other hand, we omit
* MD5 here because any new that does need a cryptographically strong checksum
* should use something better.
*/
typedef enum pg_checksum_type
{
CHECKSUM_TYPE_NONE,
CHECKSUM_TYPE_CRC32C,
CHECKSUM_TYPE_SHA224,
CHECKSUM_TYPE_SHA256,
CHECKSUM_TYPE_SHA384,
CHECKSUM_TYPE_SHA512,
} pg_checksum_type;
/*
* This is just a union of all applicable context types.
*/
typedef union pg_checksum_raw_context
{
pg_crc32c c_crc32c;
pg_cryptohash_ctx *c_sha2;
} pg_checksum_raw_context;
/*
* This structure provides a convenient way to pass the checksum type and the
* checksum context around together.
*/
typedef struct pg_checksum_context
{
pg_checksum_type type;
pg_checksum_raw_context raw_context;
} pg_checksum_context;
/*
* This is the longest possible output for any checksum algorithm supported
* by this file.
*/
#define PG_CHECKSUM_MAX_LENGTH PG_SHA512_DIGEST_LENGTH
extern bool pg_checksum_parse_type(char *name, pg_checksum_type *);
extern char *pg_checksum_type_name(pg_checksum_type);
extern int pg_checksum_init(pg_checksum_context *, pg_checksum_type);
extern int pg_checksum_update(pg_checksum_context *, const uint8 *input,
size_t len);
extern int pg_checksum_final(pg_checksum_context *, uint8 *output);
#endif