[mirror_frr.git] / nhrpd / resolver.c

/* C-Ares integration to Quagga mainloop
 * Copyright (c) 2014-2015 Timo Teräs
 *
 * This file is free software: you may copy, redistribute and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 */

#include <ares.h>
#include <ares_version.h>

#include "vector.h"
#include "thread.h"
#include "nhrpd.h"

struct resolver_state {
	ares_channel channel;
	struct thread *timeout;
	vector read_threads, write_threads;
};

static struct resolver_state state;

#define THREAD_RUNNING ((struct thread *)-1)

static void resolver_update_timeouts(struct resolver_state *r);

static int resolver_cb_timeout(struct thread *t)
{
	struct resolver_state *r = THREAD_ARG(t);

	r->timeout = THREAD_RUNNING;
	ares_process(r->channel, NULL, NULL);
	r->timeout = NULL;
	resolver_update_timeouts(r);

	return 0;
}

static int resolver_cb_socket_readable(struct thread *t)
{
	struct resolver_state *r = THREAD_ARG(t);
	int fd = THREAD_FD(t);

	vector_set_index(r->read_threads, fd, THREAD_RUNNING);
	ares_process_fd(r->channel, fd, ARES_SOCKET_BAD);
	if (vector_lookup(r->read_threads, fd) == THREAD_RUNNING) {
		t = NULL;
		thread_add_read(master, resolver_cb_socket_readable, r, fd, &t);
		vector_set_index(r->read_threads, fd, t);
	}
	resolver_update_timeouts(r);

	return 0;
}

static int resolver_cb_socket_writable(struct thread *t)
{
	struct resolver_state *r = THREAD_ARG(t);
	int fd = THREAD_FD(t);

	vector_set_index(r->write_threads, fd, THREAD_RUNNING);
	ares_process_fd(r->channel, ARES_SOCKET_BAD, fd);
	if (vector_lookup(r->write_threads, fd) == THREAD_RUNNING) {
		t = NULL;
		thread_add_write(master, resolver_cb_socket_writable, r, fd,
				 &t);
		vector_set_index(r->write_threads, fd, t);
	}
	resolver_update_timeouts(r);

	return 0;
}

static void resolver_update_timeouts(struct resolver_state *r)
{
	struct timeval *tv, tvbuf;

	if (r->timeout == THREAD_RUNNING)
		return;

	THREAD_OFF(r->timeout);
	tv = ares_timeout(r->channel, NULL, &tvbuf);
	if (tv) {
		unsigned int timeoutms = tv->tv_sec * 1000 + tv->tv_usec / 1000;
		thread_add_timer_msec(master, resolver_cb_timeout, r, timeoutms,
				      &r->timeout);
	}
}

static void ares_socket_cb(void *data, ares_socket_t fd, int readable,
			   int writable)
{
	struct resolver_state *r = (struct resolver_state *)data;
	struct thread *t;

	if (readable) {
		t = vector_lookup_ensure(r->read_threads, fd);
		if (!t) {
			thread_add_read(master, resolver_cb_socket_readable, r,
					fd, &t);
			vector_set_index(r->read_threads, fd, t);
		}
	} else {
		t = vector_lookup(r->read_threads, fd);
		if (t) {
			if (t != THREAD_RUNNING) {
				THREAD_OFF(t);
			}
			vector_unset(r->read_threads, fd);
		}
	}

	if (writable) {
		t = vector_lookup_ensure(r->write_threads, fd);
		if (!t) {
			thread_add_read(master, resolver_cb_socket_writable, r,
					fd, &t);
			vector_set_index(r->write_threads, fd, t);
		}
	} else {
		t = vector_lookup(r->write_threads, fd);
		if (t) {
			if (t != THREAD_RUNNING) {
				THREAD_OFF(t);
			}
			vector_unset(r->write_threads, fd);
		}
	}
}

void resolver_init(void)
{
	struct ares_options ares_opts;

	state.read_threads = vector_init(1);
	state.write_threads = vector_init(1);

	ares_opts = (struct ares_options){
		.sock_state_cb = &ares_socket_cb,
		.sock_state_cb_data = &state,
		.timeout = 2,
		.tries = 3,
	};

	ares_init_options(&state.channel, &ares_opts,
			  ARES_OPT_SOCK_STATE_CB | ARES_OPT_TIMEOUT
				  | ARES_OPT_TRIES);
}


static void ares_address_cb(void *arg, int status, int timeouts,
			    struct hostent *he)
{
	struct resolver_query *query = (struct resolver_query *)arg;
	union sockunion addr[16];
	size_t i;

	if (status != ARES_SUCCESS) {
		debugf(NHRP_DEBUG_COMMON, "[%p] Resolving failed", query);
		query->callback(query, -1, NULL);
		query->callback = NULL;
		return;
	}

	for (i = 0; he->h_addr_list[i] != NULL && i < ZEBRA_NUM_OF(addr); i++) {
		memset(&addr[i], 0, sizeof(addr[i]));
		addr[i].sa.sa_family = he->h_addrtype;
		switch (he->h_addrtype) {
		case AF_INET:
			memcpy(&addr[i].sin.sin_addr,
			       (uint8_t *)he->h_addr_list[i], he->h_length);
			break;
		case AF_INET6:
			memcpy(&addr[i].sin6.sin6_addr,
			       (uint8_t *)he->h_addr_list[i], he->h_length);
			break;
		}
	}

	debugf(NHRP_DEBUG_COMMON, "[%p] Resolved with %d results", query,
	       (int)i);
	query->callback(query, i, &addr[0]);
	query->callback = NULL;
}

void resolver_resolve(struct resolver_query *query, int af,
		      const char *hostname,
		      void (*callback)(struct resolver_query *, int,
				       union sockunion *))
{
	if (query->callback != NULL) {
		zlog_err(
			"Trying to resolve '%s', but previous query was not finished yet",
			hostname);
		return;
	}

	debugf(NHRP_DEBUG_COMMON, "[%p] Resolving '%s'", query, hostname);

	query->callback = callback;
	ares_gethostbyname(state.channel, hostname, af, ares_address_cb, query);
	resolver_update_timeouts(&state);
}
Commit	Line	Data
2fb975da TT	1	/* C-Ares integration to Quagga mainloop
	2	* Copyright (c) 2014-2015 Timo Teräs
	3	*
	4	* This file is free software: you may copy, redistribute and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation, either version 2 of the License, or
	7	* (at your option) any later version.
	8	*/
	9
	10	#include <ares.h>
	11	#include <ares_version.h>
	12
	13	#include "vector.h"
	14	#include "thread.h"
	15	#include "nhrpd.h"
	16
	17	struct resolver_state {
	18	ares_channel channel;
	19	struct thread *timeout;
	20	vector read_threads, write_threads;
	21	};
	22
	23	static struct resolver_state state;
	24
	25	#define THREAD_RUNNING ((struct thread *)-1)
	26
	27	static void resolver_update_timeouts(struct resolver_state *r);
	28
	29	static int resolver_cb_timeout(struct thread *t)
	30	{
	31	struct resolver_state *r = THREAD_ARG(t);
	32
	33	r->timeout = THREAD_RUNNING;
	34	ares_process(r->channel, NULL, NULL);
	35	r->timeout = NULL;
	36	resolver_update_timeouts(r);
	37
	38	return 0;
	39	}
	40
	41	static int resolver_cb_socket_readable(struct thread *t)
	42	{
	43	struct resolver_state *r = THREAD_ARG(t);
	44	int fd = THREAD_FD(t);
	45
	46	vector_set_index(r->read_threads, fd, THREAD_RUNNING);
	47	ares_process_fd(r->channel, fd, ARES_SOCKET_BAD);
	48	if (vector_lookup(r->read_threads, fd) == THREAD_RUNNING) {
	49	t = NULL;
996c9314	50	thread_add_read(master, resolver_cb_socket_readable, r, fd, &t);
2fb975da TT	51	vector_set_index(r->read_threads, fd, t);
	52	}
	53	resolver_update_timeouts(r);
	54
	55	return 0;
	56	}
	57
	58	static int resolver_cb_socket_writable(struct thread *t)
	59	{
	60	struct resolver_state *r = THREAD_ARG(t);
	61	int fd = THREAD_FD(t);
	62
	63	vector_set_index(r->write_threads, fd, THREAD_RUNNING);
	64	ares_process_fd(r->channel, ARES_SOCKET_BAD, fd);
	65	if (vector_lookup(r->write_threads, fd) == THREAD_RUNNING) {
	66	t = NULL;
ffa2c898 QY	67	thread_add_write(master, resolver_cb_socket_writable, r, fd,
ffa2c898 QY	68	&t);
2fb975da TT	69	vector_set_index(r->write_threads, fd, t);
	70	}
	71	resolver_update_timeouts(r);
	72
	73	return 0;
	74	}
	75
	76	static void resolver_update_timeouts(struct resolver_state *r)
	77	{
	78	struct timeval *tv, tvbuf;
	79
996c9314 LB	80	if (r->timeout == THREAD_RUNNING)
996c9314 LB	81	return;
2fb975da TT	82
	83	THREAD_OFF(r->timeout);
	84	tv = ares_timeout(r->channel, NULL, &tvbuf);
	85	if (tv) {
	86	unsigned int timeoutms = tv->tv_sec * 1000 + tv->tv_usec / 1000;
996c9314 LB	87	thread_add_timer_msec(master, resolver_cb_timeout, r, timeoutms,
996c9314 LB	88	&r->timeout);
2fb975da TT	89	}
	90	}
	91
996c9314 LB	92	static void ares_socket_cb(void *data, ares_socket_t fd, int readable,
996c9314 LB	93	int writable)
2fb975da	94	{
996c9314	95	struct resolver_state r = (struct resolver_state )data;
2fb975da TT	96	struct thread *t;
	97
	98	if (readable) {
	99	t = vector_lookup_ensure(r->read_threads, fd);
	100	if (!t) {
996c9314 LB	101	thread_add_read(master, resolver_cb_socket_readable, r,
996c9314 LB	102	fd, &t);
2fb975da TT	103	vector_set_index(r->read_threads, fd, t);
	104	}
	105	} else {
	106	t = vector_lookup(r->read_threads, fd);
	107	if (t) {
	108	if (t != THREAD_RUNNING) {
	109	THREAD_OFF(t);
	110	}
	111	vector_unset(r->read_threads, fd);
	112	}
	113	}
	114
	115	if (writable) {
	116	t = vector_lookup_ensure(r->write_threads, fd);
	117	if (!t) {
996c9314 LB	118	thread_add_read(master, resolver_cb_socket_writable, r,
996c9314 LB	119	fd, &t);
2fb975da TT	120	vector_set_index(r->write_threads, fd, t);
	121	}
	122	} else {
	123	t = vector_lookup(r->write_threads, fd);
	124	if (t) {
	125	if (t != THREAD_RUNNING) {
	126	THREAD_OFF(t);
	127	}
	128	vector_unset(r->write_threads, fd);
	129	}
	130	}
	131	}
	132
	133	void resolver_init(void)
	134	{
	135	struct ares_options ares_opts;
	136
	137	state.read_threads = vector_init(1);
	138	state.write_threads = vector_init(1);
	139
996c9314	140	ares_opts = (struct ares_options){
2fb975da TT	141	.sock_state_cb = &ares_socket_cb,
	142	.sock_state_cb_data = &state,
	143	.timeout = 2,
	144	.tries = 3,
	145	};
	146
	147	ares_init_options(&state.channel, &ares_opts,
996c9314 LB	148	ARES_OPT_SOCK_STATE_CB \| ARES_OPT_TIMEOUT
996c9314 LB	149	\| ARES_OPT_TRIES);
2fb975da TT	150	}
	151
	152
996c9314 LB	153	static void ares_address_cb(void *arg, int status, int timeouts,
996c9314 LB	154	struct hostent *he)
2fb975da	155	{
996c9314	156	struct resolver_query query = (struct resolver_query )arg;
2fb975da TT	157	union sockunion addr[16];
	158	size_t i;
	159
	160	if (status != ARES_SUCCESS) {
	161	debugf(NHRP_DEBUG_COMMON, "[%p] Resolving failed", query);
	162	query->callback(query, -1, NULL);
	163	query->callback = NULL;
	164	return;
	165	}
	166
	167	for (i = 0; he->h_addr_list[i] != NULL && i < ZEBRA_NUM_OF(addr); i++) {
	168	memset(&addr[i], 0, sizeof(addr[i]));
	169	addr[i].sa.sa_family = he->h_addrtype;
	170	switch (he->h_addrtype) {
	171	case AF_INET:
996c9314 LB	172	memcpy(&addr[i].sin.sin_addr,
996c9314 LB	173	(uint8_t *)he->h_addr_list[i], he->h_length);
2fb975da TT	174	break;
2fb975da TT	175	case AF_INET6:
996c9314 LB	176	memcpy(&addr[i].sin6.sin6_addr,
996c9314 LB	177	(uint8_t *)he->h_addr_list[i], he->h_length);
2fb975da TT	178	break;
	179	}
	180	}
	181
996c9314 LB	182	debugf(NHRP_DEBUG_COMMON, "[%p] Resolved with %d results", query,
996c9314 LB	183	(int)i);
2fb975da TT	184	query->callback(query, i, &addr[0]);
	185	query->callback = NULL;
	186	}
	187
996c9314 LB	188	void resolver_resolve(struct resolver_query *query, int af,
	189	const char *hostname,
	190	void (callback)(struct resolver_query , int,
	191	union sockunion *))
2fb975da TT	192	{
2fb975da TT	193	if (query->callback != NULL) {
996c9314 LB	194	zlog_err(
	195	"Trying to resolve '%s', but previous query was not finished yet",
	196	hostname);
2fb975da TT	197	return;
	198	}
	199
	200	debugf(NHRP_DEBUG_COMMON, "[%p] Resolving '%s'", query, hostname);
	201
	202	query->callback = callback;
	203	ares_gethostbyname(state.channel, hostname, af, ares_address_cb, query);
	204	resolver_update_timeouts(&state);
	205	}