Function pg_hmac_create

src/common/hmac_openssl.c:70–116

* pg_hmac_create * * Allocate a hash context. Returns NULL on failure for an OOM. The * backend issues an error, without returning. */

 * backend issues an error, without returning.
 */
pg_hmac_ctx *
pg_hmac_create(pg_cryptohash_type type)
{
	pg_hmac_ctx *ctx;

	ctx = ALLOC(sizeof(pg_hmac_ctx));
	if (ctx == NULL)
		return NULL;
	memset(ctx, 0, sizeof(pg_hmac_ctx));

	ctx->type = type;

	/*
	 * Initialization takes care of assigning the correct type for OpenSSL.
	 */
#ifdef HAVE_HMAC_CTX_NEW
#ifndef FRONTEND
	ResourceOwnerEnlargeHMAC(CurrentResourceOwner);
#endif
	ctx->hmacctx = HMAC_CTX_new();
#else
	ctx->hmacctx = ALLOC(sizeof(HMAC_CTX));
#endif

	if (ctx->hmacctx == NULL)
	{
		explicit_bzero(ctx, sizeof(pg_hmac_ctx));
		FREE(ctx);
#ifndef FRONTEND
		ereport(ERROR,
				(errcode(ERRCODE_OUT_OF_MEMORY),
				 errmsg("out of memory")));
#endif
		return NULL;
	}

#ifdef HAVE_HMAC_CTX_NEW
#ifndef FRONTEND
	ctx->resowner = CurrentResourceOwner;
	ResourceOwnerRememberHMAC(CurrentResourceOwner, PointerGetDatum(ctx));
#endif
#else
	memset(ctx->hmacctx, 0, sizeof(HMAC_CTX));
#endif							/* HAVE_HMAC_CTX_NEW */

	return ctx;
}

/*
 * pg_hmac_init