masterdump.c

非常好的dns解析软件

static isc_result_t
task_send(dns_dumpctx_t *dctx) {
	isc_event_t *event;

	event = isc_event_allocate(dctx->mctx, NULL, DNS_EVENT_DUMPQUANTUM,
				   dump_quantum, dctx, sizeof(*event));
	if (event == NULL)
		return (ISC_R_NOMEMORY);
	isc_task_send(dctx->task, &event);
	return (ISC_R_SUCCESS);
}

static isc_result_t
dumpctx_create(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
	       const dns_master_style_t *style, FILE *f, dns_dumpctx_t **dctxp,
	       dns_masterformat_t format)
{
	dns_dumpctx_t *dctx;
	isc_result_t result;
	isc_boolean_t relative;

	dctx = isc_mem_get(mctx, sizeof(*dctx));
	if (dctx == NULL)
		return (ISC_R_NOMEMORY);

	dctx->mctx = NULL;
	dctx->f = f;
	dctx->dbiter = NULL;
	dctx->db = NULL;
	dctx->version = NULL;
	dctx->done = NULL;
	dctx->done_arg = NULL;
	dctx->task = NULL;
	dctx->nodes = 0;
	dctx->first = ISC_TRUE;
	dctx->canceled = ISC_FALSE;
	dctx->file = NULL;
	dctx->tmpfile = NULL;
	dctx->format = format;

	switch (format) {
	case dns_masterformat_text:
		dctx->dumpsets = dump_rdatasets_text;
		break;
	case dns_masterformat_raw:
		dctx->dumpsets = dump_rdatasets_raw;
		break;
	default:
		INSIST(0);
		break;
	}

	result = totext_ctx_init(style, &dctx->tctx);
	if (result != ISC_R_SUCCESS) {
		UNEXPECTED_ERROR(__FILE__, __LINE__,
				 "could not set master file style");
		goto cleanup;
	}

	isc_stdtime_get(&dctx->now);
	dns_db_attach(db, &dctx->db);

	dctx->do_date = dns_db_iscache(dctx->db);

	if (dctx->format == dns_masterformat_text &&
	    (dctx->tctx.style.flags & DNS_STYLEFLAG_REL_OWNER) != 0) {
		relative = ISC_TRUE;
	} else
		relative = ISC_FALSE;
	result = dns_db_createiterator(dctx->db, relative, &dctx->dbiter);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = isc_mutex_init(&dctx->lock);
	if (result != ISC_R_SUCCESS)
		goto cleanup;
	if (version != NULL)
		dns_db_attachversion(dctx->db, version, &dctx->version);
	else if (!dns_db_iscache(db))
		dns_db_currentversion(dctx->db, &dctx->version);
	isc_mem_attach(mctx, &dctx->mctx);
	dctx->references = 1;
	dctx->magic = DNS_DCTX_MAGIC;
	*dctxp = dctx;
	return (ISC_R_SUCCESS);

 cleanup:
	if (dctx->dbiter != NULL)
		dns_dbiterator_destroy(&dctx->dbiter);
	if (dctx->db != NULL)
		dns_db_detach(&dctx->db);
	if (dctx != NULL)
		isc_mem_put(mctx, dctx, sizeof(*dctx));
	return (result);
}

static isc_result_t
dumptostreaminc(dns_dumpctx_t *dctx) {
	isc_result_t result;
	isc_buffer_t buffer;
	char *bufmem;
	isc_region_t r;
	dns_name_t *name;
	dns_fixedname_t fixname;
	unsigned int nodes;
	dns_masterrawheader_t rawheader;
	isc_uint32_t now32;
	isc_time_t start;

	bufmem = isc_mem_get(dctx->mctx, initial_buffer_length);
	if (bufmem == NULL)
		return (ISC_R_NOMEMORY);

	isc_buffer_init(&buffer, bufmem, initial_buffer_length);

	dns_fixedname_init(&fixname);
	name = dns_fixedname_name(&fixname);

	if (dctx->first) {
		switch (dctx->format) {
		case dns_masterformat_text:
			/*
			 * If the database has cache semantics, output an
			 * RFC2540 $DATE directive so that the TTLs can be
			 * adjusted when it is reloaded.  For zones it is not
			 * really needed, and it would make the file
			 * incompatible with pre-RFC2540 software, so we omit
			 * it in the zone case.
			 */
			if (dctx->do_date) {
				result = dns_time32_totext(dctx->now, &buffer);
				RUNTIME_CHECK(result == ISC_R_SUCCESS);
				isc_buffer_usedregion(&buffer, &r);
				fprintf(dctx->f, "$DATE %.*s\n",
					(int) r.length, (char *) r.base);
			}
			break;
		case dns_masterformat_raw:
			r.base = (unsigned char *)&rawheader;
			r.length = sizeof(rawheader);
			isc_buffer_region(&buffer, &r);
			isc_buffer_putuint32(&buffer, dns_masterformat_raw);
			isc_buffer_putuint32(&buffer, DNS_RAWFORMAT_VERSION);
			if (sizeof(now32) != sizeof(dctx->now)) {
				/*
				 * We assume isc_stdtime_t is a 32-bit integer,
				 * which should be the case on most cases.
				 * If it turns out to be uncommon, we'll need
				 * to bump the version number and revise the
				 * header format.
				 */
				isc_log_write(dns_lctx,
					      ISC_LOGCATEGORY_GENERAL,
					      DNS_LOGMODULE_MASTERDUMP,
					      ISC_LOG_INFO,
					      "dumping master file in raw "
					      "format: stdtime is not 32bits");
				now32 = 0;
			} else
				now32 = dctx->now;
			isc_buffer_putuint32(&buffer, now32);
			INSIST(isc_buffer_usedlength(&buffer) <=
			       sizeof(rawheader));
			result = isc_stdio_write(buffer.base, 1,
						 isc_buffer_usedlength(&buffer),
						 dctx->f, NULL);
			if (result != ISC_R_SUCCESS)
				return (result);
			isc_buffer_clear(&buffer);
			break;
		default:
			INSIST(0);
		}

		result = dns_dbiterator_first(dctx->dbiter);
		dctx->first = ISC_FALSE;
	} else
		result = ISC_R_SUCCESS;

	nodes = dctx->nodes;
	isc_time_now(&start);
	while (result == ISC_R_SUCCESS && (dctx->nodes == 0 || nodes--)) {
		dns_rdatasetiter_t *rdsiter = NULL;
		dns_dbnode_t *node = NULL;

		result = dns_dbiterator_current(dctx->dbiter, &node, name);
		if (result != ISC_R_SUCCESS && result != DNS_R_NEWORIGIN)
			break;
		if (result == DNS_R_NEWORIGIN) {
			dns_name_t *origin =
				dns_fixedname_name(&dctx->tctx.origin_fixname);
			result = dns_dbiterator_origin(dctx->dbiter, origin);
			RUNTIME_CHECK(result == ISC_R_SUCCESS);
			if ((dctx->tctx.style.flags & DNS_STYLEFLAG_REL_DATA) != 0)
				dctx->tctx.origin = origin;
			dctx->tctx.neworigin = origin;
		}
		result = dns_db_allrdatasets(dctx->db, node, dctx->version,
					     dctx->now, &rdsiter);
		if (result != ISC_R_SUCCESS) {
			dns_db_detachnode(dctx->db, &node);
			goto fail;
		}
		result = (dctx->dumpsets)(dctx->mctx, name, rdsiter,
					  &dctx->tctx, &buffer, dctx->f);
		dns_rdatasetiter_destroy(&rdsiter);
		if (result != ISC_R_SUCCESS) {
			dns_db_detachnode(dctx->db, &node);
			goto fail;
		}
		dns_db_detachnode(dctx->db, &node);
		result = dns_dbiterator_next(dctx->dbiter);
	}

	/*
	 * Work out how many nodes can be written in the time between
	 * two requests to the nameserver.  Smooth the resulting number and
	 * use it as a estimate for the number of nodes to be written in the
	 * next iteration.
	 */
	if (dctx->nodes != 0 && result == ISC_R_SUCCESS) {
		unsigned int pps = dns_pps;	/* packets per second */
		unsigned int interval;
		isc_uint64_t usecs;
		isc_time_t end;

		isc_time_now(&end);
		if (pps < 100)
			pps = 100;
		interval = 1000000 / pps;	/* interval in usecs */
		if (interval == 0)
			interval = 1;
		usecs = isc_time_microdiff(&end, &start);
		if (usecs == 0) {
			dctx->nodes = dctx->nodes * 2;
			if (dctx->nodes > 1000)
				dctx->nodes = 1000;
		} else {
			nodes = dctx->nodes * interval;
			nodes /= (unsigned int)usecs;
			if (nodes == 0)
				nodes = 1;
			else if (nodes > 1000)
				nodes = 1000;

			/* Smooth and assign. */
			dctx->nodes = (nodes + dctx->nodes * 7) / 8;

			isc_log_write(dns_lctx, ISC_LOGCATEGORY_GENERAL,
				      DNS_LOGMODULE_MASTERDUMP,
				      ISC_LOG_DEBUG(1),
				      "dumptostreaminc(%p) new nodes -> %d\n",
				      dctx, dctx->nodes);
		}
		result = dns_dbiterator_pause(dctx->dbiter);
		RUNTIME_CHECK(result == ISC_R_SUCCESS);
		result = DNS_R_CONTINUE;
	} else if (result == ISC_R_NOMORE)
		result = ISC_R_SUCCESS;
 fail:
	isc_mem_put(dctx->mctx, buffer.base, buffer.length);
	return (result);
}

isc_result_t
dns_master_dumptostreaminc(isc_mem_t *mctx, dns_db_t *db,
			   dns_dbversion_t *version,
			   const dns_master_style_t *style,
			   FILE *f, isc_task_t *task,
			   dns_dumpdonefunc_t done, void *done_arg,
			   dns_dumpctx_t **dctxp)
{
	dns_dumpctx_t *dctx = NULL;
	isc_result_t result;

	REQUIRE(task != NULL);
	REQUIRE(f != NULL);
	REQUIRE(done != NULL);

	result = dumpctx_create(mctx, db, version, style, f, &dctx,
				dns_masterformat_text);
	if (result != ISC_R_SUCCESS)
		return (result);
	isc_task_attach(task, &dctx->task);
	dctx->done = done;
	dctx->done_arg = done_arg;
	dctx->nodes = 100;

	result = task_send(dctx);
	if (result == ISC_R_SUCCESS) {
		dns_dumpctx_attach(dctx, dctxp);
		return (DNS_R_CONTINUE);
	}

	dns_dumpctx_detach(&dctx);
	return (result);
}

/*
 * Dump an entire database into a master file.
 */
isc_result_t
dns_master_dumptostream(isc_mem_t *mctx, dns_db_t *db,
			dns_dbversion_t *version,
			const dns_master_style_t *style,
			FILE *f)
{
	return (dns_master_dumptostream2(mctx, db, version, style,
					 dns_masterformat_text, f));
}

isc_result_t
dns_master_dumptostream2(isc_mem_t *mctx, dns_db_t *db,
			 dns_dbversion_t *version,
			 const dns_master_style_t *style,
			 dns_masterformat_t format, FILE *f)
{
	dns_dumpctx_t *dctx = NULL;
	isc_result_t result;

	result = dumpctx_create(mctx, db, version, style, f, &dctx, format);
	if (result != ISC_R_SUCCESS)
		return (result);

	result = dumptostreaminc(dctx);
	INSIST(result != DNS_R_CONTINUE);
	dns_dumpctx_detach(&dctx);
	return (result);
}

static isc_result_t
opentmp(isc_mem_t *mctx, const char *file, char **tempp, FILE **fp) {
	FILE *f = NULL;
	isc_result_t result;
	char *tempname = NULL;
	int tempnamelen;

	tempnamelen = strlen(file) + 20;
	tempname = isc_mem_allocate(mctx, tempnamelen);
	if (tempname == NULL)
		return (ISC_R_NOMEMORY);

	result = isc_file_mktemplate(file, tempname, tempnamelen);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = isc_file_openunique(tempname, &f);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(dns_lctx, ISC_LOGCATEGORY_GENERAL,
			      DNS_LOGMODULE_MASTERDUMP, ISC_LOG_ERROR,
			      "dumping master file: %s: open: %s",
			      tempname, isc_result_totext(result));
		goto cleanup;
	}
	*tempp = tempname;
	*fp = f;
	return (ISC_R_SUCCESS);

cleanup:
	isc_mem_free(mctx, tempname);
	return (result);
}

isc_result_t
dns_master_dumpinc(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
		   const dns_master_style_t *style, const char *filename,
		   isc_task_t *task, dns_dumpdonefunc_t done, void *done_arg,
		   dns_dumpctx_t **dctxp)
{
	return (dns_master_dumpinc2(mctx, db, version, style, filename, task,
				    done, done_arg, dctxp,
				    dns_masterformat_text));
}

isc_result_t
dns_master_dumpinc2(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
		    const dns_master_style_t *style, const char *filename,
		    isc_task_t *task, dns_dumpdonefunc_t done, void *done_arg,
		    dns_dumpctx_t **dctxp, dns_masterformat_t format)
{
	FILE *f = NULL;
	isc_result_t result;
	char *tempname = NULL;
	char *file = NULL;
	dns_dumpctx_t *dctx = NULL;

	file = isc_mem_strdup(mctx, filename);
	if (file == NULL)
		return (ISC_R_NOMEMORY);

	result = opentmp(mctx, filename, &tempname, &f);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = dumpctx_create(mctx, db, version, style, f, &dctx, format);
	if (result != ISC_R_SUCCESS) {
		(void)isc_stdio_close(f);
		(void)isc_file_remove(tempname);
		goto cleanup;
	}

	isc_task_attach(task, &dctx->task);
	dctx->done = done;
	dctx->done_arg = done_arg;
	dctx->nodes = 100;
	dctx->file = file;
	file = NULL;
	dctx->tmpfile = tempname;
	tempname = NULL;

	result = task_send(dctx);
	if (result == ISC_R_SUCCESS) {
		dns_dumpctx_attach(dctx, dctxp);
		return (DNS_R_CONTINUE);
	}

 cleanup:
	if (dctx != NULL)
		dns_dumpctx_detach(&dctx);
	if (file != NULL)
		isc_mem_free(mctx, file);
	if (tempname != NULL)
		isc_mem_free(mctx, tempname);
	return (result);
}

isc_result_t
dns_master_dump(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
		const dns_master_style_t *style, const char *filename)
{
	return (dns_master_dump2(mctx, db, version, style, filename,
				 dns_masterformat_text));
}

isc_result_t
dns_master_dump2(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
		 const dns_master_style_t *style, const char *filename,
		 dns_masterformat_t format)
{
	FILE *f = NULL;
	isc_result_t result;
	char *tempname;
	dns_dumpctx_t *dctx = NULL;

	result = opentmp(mctx, filename, &tempname, &f);
	if (result != ISC_R_SUCCESS)
		return (result);

	result = dumpctx_create(mctx, db, version, style, f, &dctx, format);
	if (result != ISC_R_SUCCESS)
		goto cleanup;

	result = dumptostreaminc(dctx);
	INSIST(result != DNS_R_CONTINUE);
	dns_dumpctx_detach(&dctx);

	result = closeandrename(f, result, tempname, filename);

 cleanup:
	isc_mem_free(mctx, tempname);
	return (result);
}

/*
 * Dump a database node into a master file.
 * XXX: this function assumes the text format.
 */
isc_result_t
dns_master_dumpnodetostream(isc_mem_t *mctx, dns_db_t *db,
			    dns_dbversion_t *version,
			    dns_dbnode_t *node, dns_name_t *name,
			    const dns_master_style_t *style,
			    FILE *f)
{
	isc_result_t result;
	isc_buffer_t buffer;
	char *bufmem;
	isc_stdtime_t now;
	dns_totext_ctx_t ctx;
	dns_rdatasetiter_t *rdsiter = NULL;

	result = totext_ctx_init(style, &ctx);
	if (result != ISC_R_SUCCESS) {
		UNEXPECTED_ERROR(__FILE__, __LINE__,
				 "could not set master file style");
		return (ISC_R_UNEXPECTED);
	}

	isc_stdtime_get(&now);

	bufmem = isc_mem_get(mctx, initial_buffer_length);
	if (bufmem == NULL)
		return (ISC_R_NOMEMORY);

	isc_buffer_init(&buffer, bufmem, initial_buffer_length);

	result = dns_db_allrdatasets(db, node, version, now, &rdsiter);
	if (result != ISC_R_SUCCESS)
		goto failure;
	result = dump_rdatasets_text(mctx, name, rdsiter, &ctx, &buffer, f);
	if (result != ISC_R_SUCCESS)
		goto failure;
	dns_rdatasetiter_destroy(&rdsiter);

	result = ISC_R_SUCCESS;

 failure:
	isc_mem_put(mctx, buffer.base, buffer.length);
	return (result);
}

isc_result_t
dns_master_dumpnode(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *version,
		    dns_dbnode_t *node, dns_name_t *name,
		    const dns_master_style_t *style, const char *filename)
{
	FILE *f = NULL;
	isc_result_t result;

	result = isc_stdio_open(filename, "w", &f);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(dns_lctx, ISC_LOGCATEGORY_GENERAL,
			      DNS_LOGMODULE_MASTERDUMP, ISC_LOG_ERROR,
			      "dumping node to file: %s: open: %s", filename,
			      isc_result_totext(result));
		return (ISC_R_UNEXPECTED);
	}

	result = dns_master_dumpnodetostream(mctx, db, version, node, name,
					     style, f);

	result = isc_stdio_close(f);
	if (result != ISC_R_SUCCESS) {
		isc_log_write(dns_lctx, ISC_LOGCATEGORY_GENERAL,
			      DNS_LOGMODULE_MASTERDUMP, ISC_LOG_ERROR,
			      "dumping master file: %s: close: %s", filename,
			      isc_result_totext(result));
		return (ISC_R_UNEXPECTED);
	}

	return (result);
}

isc_result_t
dns_master_stylecreate(dns_master_style_t **stylep, unsigned int flags,
                       unsigned int ttl_column, unsigned int class_column,
                       unsigned int type_column, unsigned int rdata_column,
                       unsigned int line_length, unsigned int tab_width,
                       isc_mem_t *mctx)
{
	dns_master_style_t *style;

	REQUIRE(stylep != NULL && *stylep == NULL);
	style = isc_mem_get(mctx, sizeof(*style));
	if (style == NULL)
		return (ISC_R_NOMEMORY);

	style->flags = flags;
	style->ttl_column = ttl_column;
	style->class_column = class_column;
	style->type_column = type_column;
	style->rdata_column = rdata_column;
	style->line_length = line_length;
	style->tab_width = tab_width;

	*stylep = style;
	return (ISC_R_SUCCESS);
}

void
dns_master_styledestroy(dns_master_style_t **stylep, isc_mem_t *mctx) {
	dns_master_style_t *style;

	REQUIRE(stylep != NULL && *stylep != NULL);
	style = *stylep;
	*stylep = NULL;
	isc_mem_put(mctx, style, sizeof(*style));
}