getdns/src/request-internal.c

/**
 *
 * /brief getdns contect management functions
 *
 * This is the meat of the API
 * Originally taken from the getdns API description pseudo implementation.
 *
 */
/*
 * Copyright (c) 2013, Versign, Inc.
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * * Neither the name of the <organization> nor the
 *   names of its contributors may be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL Verisign, Inc. BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "types-internal.h"
#include "util-internal.h"
#include <unbound.h>
#include <event2/event.h>

/* useful macros */
#define gd_malloc(sz) context->malloc(sz)
#define gd_free(ptr) context->free(ptr)

void
network_req_free(getdns_network_req * net_req)
{
	if (!net_req) {
		return;
	}
	getdns_context_t context = net_req->owner->context;
	if (net_req->result) {
		ldns_pkt_free(net_req->result);
	}
	gd_free(net_req);
}

getdns_network_req *
network_req_new(getdns_dns_req * owner,
    uint16_t request_type,
    uint16_t request_class, struct getdns_dict *extensions)
{

	getdns_context_t context = owner->context;
	getdns_network_req *net_req = gd_malloc(sizeof(getdns_network_req));
	if (!net_req) {
		return NULL;
	}
	net_req->result = NULL;
	net_req->next = NULL;

	net_req->request_type = request_type;
	net_req->request_class = request_class;
	net_req->unbound_id = -1;
	net_req->state = NET_REQ_NOT_SENT;
	net_req->owner = owner;

	/* TODO: records and other extensions */

	return net_req;
}

void
dns_req_free(getdns_dns_req * req)
{
	if (!req) {
		return;
	}
	getdns_network_req *net_req = NULL;
	getdns_context_t context = req->context;

	/* free extensions */
	getdns_dict_destroy(req->extensions);

	/* free network requests */
	net_req = req->first_req;
	while (net_req) {
		getdns_network_req *next = net_req->next;
		network_req_free(net_req);
		net_req = next;
	}

	/* cleanup timeout */
	if (req->timeout) {
		event_del(req->timeout);
		event_free(req->timeout);
	}

	if (req->local_cb_timer) {
		event_del(req->local_cb_timer);
		event_free(req->local_cb_timer);
	}

	/* free strduped name */
	free(req->name);

	gd_free(req);
}

/* create a new dns req to be submitted */
getdns_dns_req *
dns_req_new(getdns_context_t context,
    struct ub_ctx *unbound,
    const char *name, uint16_t request_type, struct getdns_dict *extensions)
{

	getdns_dns_req *result = NULL;
	getdns_network_req *req = NULL;
	getdns_return_t r;
	uint32_t both = GETDNS_EXTENSION_FALSE;

	result = gd_malloc(sizeof(getdns_dns_req));
	if (result == NULL) {
		return NULL;
	}

	result->name = strdup(name);
	result->context = context;
	result->unbound = unbound;
	result->canceled = 0;
	result->current_req = NULL;
	result->first_req = NULL;
	result->trans_id = ldns_get_random();
	result->timeout = NULL;
	result->local_cb_timer = NULL;
	result->ev_base = NULL;

	getdns_dict_copy(extensions, &result->extensions);

	/* will be set by caller */
	result->user_pointer = NULL;
	result->user_callback = NULL;

	/* create the requests */
	req = network_req_new(result,
	    request_type, LDNS_RR_CLASS_IN, extensions);
	if (!req) {
		dns_req_free(result);
		return NULL;
	}

	result->current_req = req;
	result->first_req = req;

	/* tack on A or AAAA if needed */
	r = getdns_dict_get_int(extensions,
	    GETDNS_STR_EXTENSION_RETURN_BOTH_V4_AND_V6, &both);
	if (r == GETDNS_RETURN_GOOD &&
	    both == GETDNS_EXTENSION_TRUE &&
	    (request_type == GETDNS_RRTYPE_A
		|| request_type == GETDNS_RRTYPE_AAAA)) {

		uint16_t next_req_type =
		    (request_type ==
		    GETDNS_RRTYPE_A) ? GETDNS_RRTYPE_AAAA : GETDNS_RRTYPE_A;
		getdns_network_req *next_req = network_req_new(result,
		    next_req_type,
		    LDNS_RR_CLASS_IN,
		    extensions);
		if (!next_req) {
			dns_req_free(result);
			return NULL;
		}
		req->next = next_req;
	}

	return result;
}