[secnet] / resolver.c

/* Name resolution using adns */

#include <errno.h>
#include "secnet.h"
#ifndef HAVE_LIBADNS
#error secnet requires ADNS version 1.0 or above
#endif
#include <adns.h>


struct adns {
    closure_t cl;
    struct resolver_if ops;
    struct cloc loc;
    adns_state ast;
};

struct query {
    void *cst;
    resolve_answer_fn *answer;
    adns_query query;
};

static resolve_request_fn resolve_request;
static bool_t resolve_request(void *sst, cstring_t name,
			      resolve_answer_fn *cb, void *cst)
{
    struct adns *st=sst;
    struct query *q;
    int rv;

    q=safe_malloc(sizeof *q,"resolve_request");
    q->cst=cst;
    q->answer=cb;

    rv=adns_submit(st->ast, name, adns_r_a, 0, q, &q->query);

    return rv==0;
}

static int resolver_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
			       int *timeout_io)
{
    struct adns *st=sst;
    return adns_beforepoll(st->ast, fds, nfds_io, timeout_io, tv_now);
}

static void resolver_afterpoll(void *sst, struct pollfd *fds, int nfds)
{
    struct adns *st=sst;
    adns_query aq;
    adns_answer *ans;
    void *qp;
    struct query *q;
    int rv;

    adns_afterpoll(st->ast, fds, nfds, tv_now);

    while (True) {
	aq=NULL;
	rv=adns_check(st->ast, &aq, &ans, &qp);
	if (rv==0) {
	    q=qp;
	    if (ans->status!=adns_s_ok) {
		q->answer(q->cst,NULL); /* Failure */
		free(q);
		free(ans);
	    } else {
		q->answer(q->cst,ans->rrs.inaddr);
		free(q);
		free(ans);
	    }
	} else if (rv==EAGAIN || rv==ESRCH) {
	    break;
	} else {
	    fatal("resolver_afterpoll: adns_check() returned %d",rv);
	}
    }

    return;
}

/* Initialise adns, using parameters supplied */
static list_t *adnsresolver_apply(closure_t *self, struct cloc loc,
				  dict_t *context, list_t *args)
{
    struct adns *st;
    dict_t *d;
    item_t *i;
    string_t conf;

    st=safe_malloc(sizeof(*st),"adnsresolver_apply");
    st->cl.description="adns";
    st->cl.type=CL_RESOLVER;
    st->cl.apply=NULL;
    st->cl.interface=&st->ops;
    st->loc=loc;
    st->ops.st=st;
    st->ops.request=resolve_request;

    i=list_elem(args,0);
    if (!i || i->type!=t_dict) {
	cfgfatal(st->loc,"adns","first argument must be a dictionary\n");
    }
    d=i->data.dict;
    conf=dict_read_string(d,"config",False,"adns",loc);

    if (conf) {
	if (adns_init_strcfg(&st->ast, 0, 0, conf)) {
	    fatal_perror("Failed to initialise ADNS");
	}
    } else {
	if (adns_init(&st->ast, 0, 0)) {
	    fatal_perror("Failed to initialise ADNS");
	}
    }

    register_for_poll(st, resolver_beforepoll, resolver_afterpoll,
		      ADNS_POLLFDS_RECOMMENDED+5,"resolver");

    return new_closure(&st->cl);
}

void resolver_module(dict_t *dict)
{
    add_closure(dict,"adns",adnsresolver_apply);
}
Commit	Line	Data
2fe58dfd SE	1	/* Name resolution using adns */
	2
	3	#include <errno.h>
	4	#include "secnet.h"
d3fe100d SE	5	#ifndef HAVE_LIBADNS
	6	#error secnet requires ADNS version 1.0 or above
	7	#endif
2fe58dfd SE	8	#include <adns.h>
2fe58dfd SE	9
d3fe100d	10
2fe58dfd SE	11	struct adns {
	12	closure_t cl;
	13	struct resolver_if ops;
	14	struct cloc loc;
	15	adns_state ast;
	16	};
	17
	18	struct query {
	19	void *cst;
	20	resolve_answer_fn *answer;
	21	adns_query query;
	22	};
	23
fe5e9cc4 SE	24	static resolve_request_fn resolve_request;
fe5e9cc4 SE	25	static bool_t resolve_request(void *sst, cstring_t name,
2fe58dfd SE	26	resolve_answer_fn cb, void cst)
	27	{
	28	struct adns *st=sst;
	29	struct query *q;
	30	int rv;
	31
	32	q=safe_malloc(sizeof *q,"resolve_request");
	33	q->cst=cst;
	34	q->answer=cb;
	35
	36	rv=adns_submit(st->ast, name, adns_r_a, 0, q, &q->query);
	37
	38	return rv==0;
	39	}
	40
	41	static int resolver_beforepoll(void sst, struct pollfd fds, int *nfds_io,
90a39563	42	int *timeout_io)
2fe58dfd SE	43	{
	44	struct adns *st=sst;
	45	return adns_beforepoll(st->ast, fds, nfds_io, timeout_io, tv_now);
	46	}
	47
90a39563	48	static void resolver_afterpoll(void sst, struct pollfd fds, int nfds)
2fe58dfd SE	49	{
	50	struct adns *st=sst;
	51	adns_query aq;
	52	adns_answer *ans;
	53	void *qp;
	54	struct query *q;
	55	int rv;
	56
	57	adns_afterpoll(st->ast, fds, nfds, tv_now);
	58
	59	while (True) {
	60	aq=NULL;
	61	rv=adns_check(st->ast, &aq, &ans, &qp);
	62	if (rv==0) {
	63	q=qp;
	64	if (ans->status!=adns_s_ok) {
	65	q->answer(q->cst,NULL); /* Failure */
	66	free(q);
	67	free(ans);
	68	} else {
	69	q->answer(q->cst,ans->rrs.inaddr);
	70	free(q);
	71	free(ans);
	72	}
	73	} else if (rv==EAGAIN \|\| rv==ESRCH) {
	74	break;
	75	} else {
4f5e39ec	76	fatal("resolver_afterpoll: adns_check() returned %d",rv);
2fe58dfd SE	77	}
	78	}
	79
	80	return;
	81	}
	82
	83	/* Initialise adns, using parameters supplied */
	84	static list_t adnsresolver_apply(closure_t self, struct cloc loc,
	85	dict_t context, list_t args)
	86	{
	87	struct adns *st;
	88	dict_t *d;
	89	item_t *i;
	90	string_t conf;
	91
	92	st=safe_malloc(sizeof(*st),"adnsresolver_apply");
	93	st->cl.description="adns";
	94	st->cl.type=CL_RESOLVER;
	95	st->cl.apply=NULL;
	96	st->cl.interface=&st->ops;
	97	st->loc=loc;
	98	st->ops.st=st;
	99	st->ops.request=resolve_request;
	100
	101	i=list_elem(args,0);
	102	if (!i \|\| i->type!=t_dict) {
	103	cfgfatal(st->loc,"adns","first argument must be a dictionary\n");
	104	}
	105	d=i->data.dict;
	106	conf=dict_read_string(d,"config",False,"adns",loc);
	107
	108	if (conf) {
	109	if (adns_init_strcfg(&st->ast, 0, 0, conf)) {
	110	fatal_perror("Failed to initialise ADNS");
	111	}
	112	} else {
	113	if (adns_init(&st->ast, 0, 0)) {
	114	fatal_perror("Failed to initialise ADNS");
	115	}
	116	}
	117
	118	register_for_poll(st, resolver_beforepoll, resolver_afterpoll,
	119	ADNS_POLLFDS_RECOMMENDED+5,"resolver");
	120
	121	return new_closure(&st->cl);
	122	}
	123
2fe58dfd SE	124	void resolver_module(dict_t *dict)
	125	{
	126	add_closure(dict,"adns",adnsresolver_apply);
	127	}