getdns/src/convert.c

/**
 *
 * \file convert.c
 * @brief getdns label conversion functions
 *
 */

/*
 * Copyright (c) 2013, NLnet Labs, Verisign, 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 names of the copyright holders 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 <stdio.h>
#include <string.h>
#include <arpa/inet.h>
#include <locale.h>
#include "config.h"
#ifdef HAVE_LIBIDN
#include <stringprep.h>
#include <idna.h>
#endif
#include "getdns/getdns.h"
#include "getdns/getdns_extra.h"
#include "util-internal.h"
#include "gldns/wire2str.h"
#include "gldns/str2wire.h"
#include "dict.h"

/* stuff to make it compile pedantically */
#define UNUSED_PARAM(x) ((void)(x))

getdns_return_t
getdns_convert_dns_name_to_fqdn(
    const getdns_bindata *dns_name_wire_fmt, char **fqdn_as_string)
{
	char *r;

	if (!dns_name_wire_fmt || !fqdn_as_string)
		return GETDNS_RETURN_INVALID_PARAMETER;

	if (!(r = gldns_wire2str_dname(
	    dns_name_wire_fmt->data, dns_name_wire_fmt->size)))
		return GETDNS_RETURN_GENERIC_ERROR;

	*fqdn_as_string = r;
	return GETDNS_RETURN_GOOD;
}

getdns_return_t
getdns_convert_fqdn_to_dns_name(
    const char *fqdn_as_string, getdns_bindata **dns_name_wire_fmt)
{
	getdns_bindata *r;
	uint8_t *dname;
	size_t len;

	if (!fqdn_as_string || !dns_name_wire_fmt)
		return GETDNS_RETURN_INVALID_PARAMETER;

	if (!(r = malloc(sizeof(getdns_bindata))))
		return GETDNS_RETURN_MEMORY_ERROR;

	if (!(dname = gldns_str2wire_dname(fqdn_as_string, &len))) {
		free(r);
		return GETDNS_RETURN_GENERIC_ERROR;
	}
	r->size = len;
	r->data = dname;
	*dns_name_wire_fmt = r;
	return GETDNS_RETURN_GOOD;
}

/*---------------------------------------- getdns_convert_alabel_to_ulabel */
/**
 * Convert UTF-8 string into an ACE-encoded domain
 * It is the application programmer's responsibility to free()
 * the returned buffer after use
 *
 * @param ulabel the UTF-8-encoded domain name to convert
 * @return pointer to ACE-encoded string
 * @return NULL if conversion fails
 */

char *
getdns_convert_ulabel_to_alabel(const char *ulabel)
{
#ifdef HAVE_LIBIDN
    int ret;
    char *buf;
    char *prepped;
    char *prepped2;

    if (ulabel == NULL)
	return 0;
    prepped2 = malloc(BUFSIZ);
    if(!prepped2)
	    return 0;
    setlocale(LC_ALL, "");
    if ((prepped = stringprep_locale_to_utf8(ulabel)) == 0) {
	/* convert to utf8 fails, which it can, but continue anyway */
	if(strlen(ulabel)+1 > BUFSIZ) {
	    free(prepped2);
	    return 0;
	}
	memcpy(prepped2, ulabel, strlen(ulabel)+1);
    } else {
	if(strlen(prepped)+1 > BUFSIZ) {
	    free(prepped);
	    free(prepped2);
	    return 0;
	}
	memcpy(prepped2, prepped, strlen(prepped)+1);
	free(prepped);
    }
    if ((ret = stringprep(prepped2, BUFSIZ, 0, stringprep_nameprep)) != STRINGPREP_OK) {
	free(prepped2);
	return 0;
    }
    if ((ret = idna_to_ascii_8z(prepped2, &buf, 0)) != IDNA_SUCCESS)  {
	free(prepped2);
	return 0;
    }
    free(prepped2);
    return buf;
#else
    return NULL;
#endif
}

/*---------------------------------------- getdns_convert_alabel_to_ulabel */
/**
 * Convert ACE-encoded domain name into a UTF-8 string.
 * It is the application programmer's responsibility to free()
 * the returned buffer after use
 *
 * @param alabel the ACE-encoded domain name to convert
 * @return pointer to UTF-8 string
 * @return NULL if conversion fails
 */

char *
getdns_convert_alabel_to_ulabel(const char *alabel)
{
#ifdef HAVE_LIBIDN
    int  ret;              /* just in case we might want to use it someday */
    char *buf;

    if (alabel == NULL)
        return 0;
    if ((ret = idna_to_unicode_8z8z(alabel, &buf, 0)) != IDNA_SUCCESS)  {
        return NULL;
    }
    return buf;
#else
    return NULL;
#endif
}


char *
getdns_display_ip_address(const struct getdns_bindata
    *bindata_of_ipv4_or_ipv6_address)
{
	char buff[256];
	if (!bindata_of_ipv4_or_ipv6_address ||
	    bindata_of_ipv4_or_ipv6_address->size == 0 ||
	    !bindata_of_ipv4_or_ipv6_address->data) {
		return NULL;
	}
	if (bindata_of_ipv4_or_ipv6_address->size == 4) {
		const char *ipStr = inet_ntop(AF_INET,
		    bindata_of_ipv4_or_ipv6_address->data,
		    buff,
		    256);
		if (ipStr) {
			return strdup(ipStr);
		}
	} else if (bindata_of_ipv4_or_ipv6_address->size == 16) {
		const char *ipStr = inet_ntop(AF_INET6,
		    bindata_of_ipv4_or_ipv6_address->data,
		    buff,
		    256);
		if (ipStr) {
			return strdup(ipStr);
		}
	}
	return NULL;
}

getdns_return_t
getdns_strerror(getdns_return_t err, char *buf, size_t buflen)
{
	const char *err_str = getdns_get_errorstr_by_id(err);

	(void) snprintf(buf, buflen, "%s",
	    err_str ? err_str : "/* <unknown getdns value> */");

	return GETDNS_RETURN_GOOD;
}				/* getdns_strerror */

getdns_return_t
getdns_rr_dict2wire(
    const getdns_dict *rr_dict, uint8_t *wire, size_t *wire_sz)
{
	getdns_return_t r;
	gldns_buffer gbuf;

	if (!rr_dict || !wire || !wire_sz)
		return GETDNS_RETURN_INVALID_PARAMETER;

	gldns_buffer_init_frm_data(&gbuf, wire, *wire_sz);
	r = _getdns_rr_dict2wire(rr_dict, &gbuf);
	*wire_sz = gldns_buffer_position(&gbuf);

	if (r)
		return r;

	if (gldns_buffer_position(&gbuf) == 0 ||
	    gldns_buffer_position(&gbuf) > gldns_buffer_capacity(&gbuf))
		return GETDNS_RETURN_GENERIC_ERROR;

	return GETDNS_RETURN_GOOD;
}

getdns_return_t
getdns_wire2rr_dict(
    const uint8_t *wire, size_t wire_len, getdns_dict **rr_dict)
{
	static struct mem_funcs plain_mem_funcs = {
		MF_PLAIN, .mf.pln = { malloc, realloc, free }
	};
	_getdns_rr_iter rr_iter_spc, *rr_iter;

	if (!wire || !rr_dict)
		return GETDNS_RETURN_INVALID_PARAMETER;

	if (!(rr_iter = _getdns_single_rr_iter_init(
	    &rr_iter_spc, wire, wire_len)))
		return GETDNS_RETURN_GENERIC_ERROR;

	if (!(*rr_dict = _getdns_rr_iter2rr_dict(&plain_mem_funcs, rr_iter)))
		return GETDNS_RETURN_MEMORY_ERROR;

	return GETDNS_RETURN_GOOD;
}

getdns_return_t
getdns_rr_dict2str(
    const getdns_dict *rr_dict, char **str)
{
	getdns_return_t r;
	gldns_buffer gbuf;
	uint8_t buf_spc[4096], *buf = buf_spc;
	size_t sz;

	if (!rr_dict || !str)
		return GETDNS_RETURN_INVALID_PARAMETER;

	gldns_buffer_init_frm_data(&gbuf, buf, sizeof(buf_spc));
	r = _getdns_rr_dict2wire(rr_dict, &gbuf);
	if (gldns_buffer_position(&gbuf) > sizeof(buf_spc)) {
		if (!(buf = GETDNS_XMALLOC(
		    rr_dict->mf, uint8_t, (sz = gldns_buffer_position(&gbuf))))) {
			return GETDNS_RETURN_MEMORY_ERROR;
		}
		gldns_buffer_init_frm_data(&gbuf, buf, sz);
		r = _getdns_rr_dict2wire(rr_dict, &gbuf);
	}
	if (r) {
		if (buf != buf_spc)
			GETDNS_FREE(rr_dict->mf, buf);
		return r;
	}
	if (!(*str = gldns_wire2str_rr(gldns_buffer_begin(&gbuf),
	    gldns_buffer_position(&gbuf))))
		r = GETDNS_RETURN_MEMORY_ERROR;

	if (buf != buf_spc)
		GETDNS_FREE(rr_dict->mf, buf);
	return r;
}

getdns_return_t
getdns_str2rr_dict(
    const char *str, getdns_dict **rr_dict, const char *origin, uint32_t default_ttl)
{
	uint8_t wire_spc[4096], *wire = wire_spc;
	uint8_t origin_spc[256], *origin_wf;
	size_t origin_len = sizeof(origin_spc), wire_len = sizeof(wire_spc);
	int e;
	getdns_return_t r;

	if (!str || !rr_dict)
		return GETDNS_RETURN_INVALID_PARAMETER;

	if (!origin)
		origin_wf = NULL;

	else if (gldns_str2wire_dname_buf(origin, origin_spc, &origin_len))
		return GETDNS_RETURN_GENERIC_ERROR;
	else
		origin_wf = origin_spc;

	e = gldns_str2wire_rr_buf(str, wire, &wire_len,
	    NULL, default_ttl, origin_wf, origin_len, NULL, 0);
	if (GLDNS_WIREPARSE_ERROR(e) == GLDNS_WIREPARSE_ERR_BUFFER_TOO_SMALL) {
		if (!(wire = malloc((wire_len = GLDNS_RR_BUF_SIZE))))
			return GETDNS_RETURN_MEMORY_ERROR;
		e = gldns_str2wire_rr_buf(str, wire, &wire_len,
	            NULL, default_ttl, origin_wf, origin_len, NULL, 0);
	}
	if (e) {
		if (wire != wire_spc)
			free(wire);
		return GETDNS_RETURN_GENERIC_ERROR;
	}
	r = getdns_wire2rr_dict(wire, wire_len, rr_dict);
	if (wire != wire_spc)
		free(wire);
	return r;
}

/* convert.c */