LDNS:

LDNS is a DNS BSD-licensed resolver library which supports DNSSEC.

http://nlnetlabs.nl/projects/ldns/

	Simon Vallet / Genoscope

# Check whether user wants to use ldns

LDNS_MSG="no"

AC_ARG_WITH(ldns,

	[  --with-ldns[[=PATH]]      Use ldns for DNSSEC support (optionally in PATH)],

    [

        if test "x$withval" != "xno" ; then

			if test "x$withval" != "xyes" ; then

				CPPFLAGS="$CPPFLAGS -I${withval}/include"

				LDFLAGS="$LDFLAGS -L${withval}/lib"

			fi

            AC_DEFINE(HAVE_LDNS, 1, [Define if you want ldns support])

            LIBS="-lldns $LIBS"

            LDNS_MSG="yes"

            AC_MSG_CHECKING([for ldns support])

            AC_LINK_IFELSE(

                [AC_LANG_SOURCE([[

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#include <ldns/ldns.h>

int main() { ldns_status status = ldns_verify_trusted(NULL, NULL, NULL, NULL); status=LDNS_STATUS_OK; exit(0); }

                                ]])

                ],

				[AC_MSG_RESULT(yes)],

				[

					AC_MSG_RESULT(no)

					AC_MSG_ERROR([** Incomplete or missing ldns libraries.])

				])

        fi

    ]

)

/* $OpenBSD: getrrsetbyname.c,v 1.10 2005/03/30 02:58:28 tedu Exp $ */

/*

 * Copyright (c) 2007 Simon Vallet / Genoscope <svallet@genoscope.cns.fr>

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 *

 * 2. 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.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.

 */

/*

 * Portions Copyright (c) 1999-2001 Internet Software Consortium.

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM

 * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL

 * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,

 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING

 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,

 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION

 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include "includes.h"

#if !defined (HAVE_GETRRSETBYNAME) && defined (HAVE_LDNS)

#include <stdlib.h>

#include <string.h>

#include <ldns/ldns.h>

#include "getrrsetbyname.h"

#include "log.h"

#include "xmalloc.h"

#define malloc(x)	(xmalloc(x))

#define calloc(x, y)	(xcalloc((x),(y)))

#define free(x)		(xfree(x))

int

getrrsetbyname(const char *hostname, unsigned int rdclass,

	       unsigned int rdtype, unsigned int flags,

	       struct rrsetinfo **res)

{

	int result;

	unsigned int i, j, index_ans, index_sig;

	struct rrsetinfo *rrset = NULL;

	struct rdatainfo *rdata;

	size_t len;

	ldns_resolver *ldns_res;

	ldns_rdf *domain = NULL;

	ldns_pkt *pkt = NULL;

	ldns_rr_list *rrsigs = NULL, *rrdata = NULL;

	ldns_status err;

	ldns_rr *rr;

	/* check for invalid class and type */

	if (rdclass > 0xffff || rdtype > 0xffff) {

		result = ERRSET_INVAL;

		goto fail;

	}

	/* don't allow queries of class or type ANY */

	if (rdclass == 0xff || rdtype == 0xff) {

		result = ERRSET_INVAL;

		goto fail;

	}

	/* don't allow flags yet, unimplemented */

	if (flags) {

		result = ERRSET_INVAL;

		goto fail;

	}

	/* Initialize resolver from resolv.conf */

	domain = ldns_dname_new_frm_str(hostname);

	if ((err = ldns_resolver_new_frm_file(&ldns_res, NULL)) != \

	    LDNS_STATUS_OK) {

		result = ERRSET_FAIL;

		goto fail;

	}

#ifdef LDNS_DEBUG

	ldns_resolver_set_debug(ldns_res, true);

#endif /* LDNS_DEBUG */

	ldns_resolver_set_dnssec(ldns_res, true); /* Use DNSSEC */

	/* make query */

	pkt = ldns_resolver_query(ldns_res, domain, rdtype, rdclass, LDNS_RD);

	/*** TODO: finer errcodes -- see original **/

	if (!pkt || ldns_pkt_ancount(pkt) < 1) {

		result = ERRSET_FAIL;

		goto fail;

	}

	/* initialize rrset */

	rrset = calloc(1, sizeof(struct rrsetinfo));

	if (rrset == NULL) {

		result = ERRSET_NOMEMORY;

		goto fail;

	}

	rrdata = ldns_pkt_rr_list_by_type(pkt, rdtype, LDNS_SECTION_ANSWER);

	rrset->rri_nrdatas = ldns_rr_list_rr_count(rrdata);

	if (!rrset->rri_nrdatas) {

		result = ERRSET_NODATA;

		goto fail;

	}

	/* copy name from answer section */

	len = ldns_rdf_size(ldns_rr_owner(ldns_rr_list_rr(rrdata, 0)));

	if ((rrset->rri_name = malloc(len)) == NULL) {

		result = ERRSET_NOMEMORY;

		goto fail;

	}

	memcpy(rrset->rri_name,

	    ldns_rdf_data(ldns_rr_owner(ldns_rr_list_rr(rrdata, 0))), len);

	rrset->rri_rdclass = ldns_rr_get_class(ldns_rr_list_rr(rrdata, 0));

	rrset->rri_rdtype = ldns_rr_get_type(ldns_rr_list_rr(rrdata, 0));

	rrset->rri_ttl = ldns_rr_ttl(ldns_rr_list_rr(rrdata, 0));

	debug2("ldns: got %u answers from DNS", rrset->rri_nrdatas);

	/* Check for authenticated data */

	if (ldns_pkt_ad(pkt)) {

		rrset->rri_flags |= RRSET_VALIDATED;

	} else { /* AD is not set, try autonomous validation */

		ldns_rr_list * trusted_keys = ldns_rr_list_new();

		debug2("ldns: trying to validate RRset");

		/* Get eventual sigs */

		rrsigs = ldns_pkt_rr_list_by_type(pkt, LDNS_RR_TYPE_RRSIG,

		    LDNS_SECTION_ANSWER);

		rrset->rri_nsigs = ldns_rr_list_rr_count(rrsigs);

		debug2("ldns: got %u signature(s) (RRTYPE %u) from DNS",

		       rrset->rri_nsigs, LDNS_RR_TYPE_RRSIG);

		if ((err = ldns_verify_trusted(ldns_res, rrdata, rrsigs,

		     trusted_keys)) == LDNS_STATUS_OK) {

			rrset->rri_flags |= RRSET_VALIDATED;

			debug2("ldns: RRset is signed with a valid key");

		} else {

			debug2("ldns: RRset validation failed: %s",

			    ldns_get_errorstr_by_id(err));

		}

		ldns_rr_list_deep_free(trusted_keys);

	}

	/* allocate memory for answers */

	rrset->rri_rdatas = calloc(rrset->rri_nrdatas,

	   sizeof(struct rdatainfo));

	if (rrset->rri_rdatas == NULL) {

		result = ERRSET_NOMEMORY;

		goto fail;

	}

	/* allocate memory for signatures */

	if (rrset->rri_nsigs > 0) {

		rrset->rri_sigs = calloc(rrset->rri_nsigs,

		    sizeof(struct rdatainfo));

		if (rrset->rri_sigs == NULL) {

			result = ERRSET_NOMEMORY;

			goto fail;

		}

	}

	/* copy answers & signatures */

	for (i=0, index_ans=0, index_sig=0; i< pkt->_header->_ancount; i++) {

		rdata = NULL;

		rr = ldns_rr_list_rr(ldns_pkt_answer(pkt), i);

		if (ldns_rr_get_class(rr) == rrset->rri_rdclass &&

		    ldns_rr_get_type(rr) == rrset->rri_rdtype) {

			rdata = &rrset->rri_rdatas[index_ans++];

		}

		if (rr->_rr_class == rrset->rri_rdclass &&

		    rr->_rr_type == LDNS_RR_TYPE_RRSIG) {

			rdata = &rrset->rri_sigs[index_sig++];

		}

		if (rdata) {

			size_t rdata_offset = 0;

			rdata->rdi_length = 0;

			for (j=0; j< rr->_rd_count; j++) {

				rdata->rdi_length +=

				    ldns_rdf_size(ldns_rr_rdf(rr, j));

			}

			rdata->rdi_data = malloc(rdata->rdi_length);

			if (rdata->rdi_data == NULL) {

				result = ERRSET_NOMEMORY;

				goto fail;

			}

			/* Re-create the raw DNS RDATA */

			for (j=0; j< rr->_rd_count; j++) {

				len = ldns_rdf_size(ldns_rr_rdf(rr, j));

				memcpy(rdata->rdi_data + rdata_offset,

				       ldns_rdf_data(ldns_rr_rdf(rr, j)), len);

				rdata_offset += len;

			}

		}

	}

	*res = rrset;

	result = ERRSET_SUCCESS;

fail:

	/* freerrset(rrset); */

	ldns_rdf_deep_free(domain);

	ldns_pkt_free(pkt);

	ldns_rr_list_deep_free(rrsigs);

	ldns_rr_list_deep_free(rrdata);

	ldns_resolver_deep_free(ldns_res);

	return result;

}

void

freerrset(struct rrsetinfo *rrset)

{

	u_int16_t i;

	if (rrset == NULL)

		return;

	if (rrset->rri_rdatas) {

		for (i = 0; i < rrset->rri_nrdatas; i++) {

			if (rrset->rri_rdatas[i].rdi_data == NULL)

				break;

			free(rrset->rri_rdatas[i].rdi_data);

		}

		free(rrset->rri_rdatas);

	}

	if (rrset->rri_sigs) {

		for (i = 0; i < rrset->rri_nsigs; i++) {

			if (rrset->rri_sigs[i].rdi_data == NULL)

				break;

			free(rrset->rri_sigs[i].rdi_data);

		}

		free(rrset->rri_sigs);

	}

	if (rrset->rri_name)

		free(rrset->rri_name);

	free(rrset);

}

#endif /* !defined (HAVE_GETRRSETBYNAME) && defined (HAVE_LDNS) */