/*
* checkconf/unbound-host.c - replacement for host that supports validation.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 NLNET LABS 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 THE COPYRIGHT
* HOLDER OR CONTRIBUTORS 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.
*/
/**
* \file
*
* This file performs functionality like 'host', and also supports validation.
* It uses the libunbound library.
*/
#include "config.h"
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
/* remove alloc checks, not in this part of the code */
#ifdef UNBOUND_ALLOC_STATS
#undef malloc
#undef calloc
#undef free
#undef realloc
#endif
#ifdef UNBOUND_ALLOC_LITE
#undef malloc
#undef calloc
#undef free
#undef realloc
#undef strdup
#define unbound_lite_wrapstr(s) s
#endif
#include "libunbound/unbound.h"
#include "sldns/rrdef.h"
#include "sldns/wire2str.h"
#ifdef HAVE_NSS
/* nss3 */
#include "nss.h"
#endif
/** verbosity for unbound-host app */
static int verb = 0;
/** Give unbound-host usage, and exit (1). */
static void
usage()
{
printf("Usage: unbound-host [-vdhr46] [-c class] [-t type] hostname\n");
printf(" [-y key] [-f keyfile] [-F namedkeyfile]\n");
printf(" [-C configfile]\n");
printf(" Queries the DNS for information.\n");
printf(" The hostname is looked up for IP4, IP6 and mail.\n");
printf(" If an ip-address is given a reverse lookup is done.\n");
printf(" Use the -v option to see DNSSEC security information.\n");
printf(" -t type what type to look for.\n");
printf(" -c class what class to look for, if not class IN.\n");
printf(" -y 'keystring' specify trust anchor, DS or DNSKEY, like\n");
printf(" -y 'example.com DS 31560 5 1 1CFED8478...'\n");
printf(" -D DNSSEC enable with default root anchor\n");
printf(" from %s\n", ROOT_ANCHOR_FILE);
printf(" -f keyfile read trust anchors from file, with lines as -y.\n");
printf(" -F keyfile read named.conf-style trust anchors.\n");
printf(" -C config use the specified unbound.conf (none read by default)\n");
printf(" -r read forwarder information from /etc/resolv.conf\n");
printf(" breaks validation if the fwder does not do DNSSEC.\n");
printf(" -v be more verbose, shows nodata and security.\n");
printf(" -d debug, traces the action, -d -d shows more.\n");
printf(" -4 use ipv4 network, avoid ipv6.\n");
printf(" -6 use ipv6 network, avoid ipv4.\n");
printf(" -h show this usage help.\n");
printf("Version %s\n", PACKAGE_VERSION);
printf("BSD licensed, see LICENSE in source package for details.\n");
printf("Report bugs to %s\n", PACKAGE_BUGREPORT);
exit(1);
}
/** determine if str is ip4 and put into reverse lookup format */
static int
isip4(const char* nm, char** res)
{
struct in_addr addr;
/* ddd.ddd.ddd.ddd.in-addr.arpa. is less than 32 */
char buf[32];
if(inet_pton(AF_INET, nm, &addr) <= 0) {
return 0;
}
snprintf(buf, sizeof(buf), "%u.%u.%u.%u.in-addr.arpa",
(unsigned)((uint8_t*)&addr)[3], (unsigned)((uint8_t*)&addr)[2],
(unsigned)((uint8_t*)&addr)[1], (unsigned)((uint8_t*)&addr)[0]);
*res = strdup(buf);
return 1;
}
/** determine if str is ip6 and put into reverse lookup format */
static int
isip6(const char* nm, char** res)
{
struct in6_addr addr;
/* [nibble.]{32}.ip6.arpa. is less than 128 */
const char* hex = "0123456789abcdef";
char buf[128];
char *p;
int i;
if(inet_pton(AF_INET6, nm, &addr) <= 0) {
return 0;
}
p = buf;
for(i=15; i>=0; i--) {
uint8_t b = ((uint8_t*)&addr)[i];
*p++ = hex[ (b&0x0f) ];
*p++ = '.';
*p++ = hex[ (b&0xf0) >> 4 ];
*p++ = '.';
}
snprintf(buf+16*4, sizeof(buf)-16*4, "ip6.arpa");
*res = strdup(buf);
if(!*res) {
fprintf(stderr, "error: out of memory\n");
exit(1);
}
return 1;
}
/** massage input name */
static char*
massage_qname(const char* nm, int* reverse)
{
/* recognise IP4 and IP6, create reverse addresses if needed */
char* res;
if(isip4(nm, &res)) {
*reverse = 1;
} else if(isip6(nm, &res)) {
*reverse = 1;
} else {
res = strdup(nm);
}
if(!res) {
fprintf(stderr, "error: out of memory\n");
exit(1);
}
return res;
}
/** massage input type */
static int
massage_type(const char* t, int reverse, int* multi)
{
if(t) {
int r = sldns_get_rr_type_by_name(t);
if(r == 0 && strcasecmp(t, "TYPE0") != 0 &&
strcmp(t, "") != 0) {
fprintf(stderr, "error unknown type %s\n", t);
exit(1);
}
return r;
}
if(!t && reverse)
return LDNS_RR_TYPE_PTR;
*multi = 1;
return LDNS_RR_TYPE_A;
}
/** massage input class */
static int
massage_class(const char* c)
{
if(c) {
int r = sldns_get_rr_class_by_name(c);
if(r == 0 && strcasecmp(c, "CLASS0") != 0 &&
strcmp(c, "") != 0) {
fprintf(stderr, "error unknown class %s\n", c);
exit(1);
}
return r;
}
return LDNS_RR_CLASS_IN;
}
/** nice security status string */
static const char*
secure_str(struct ub_result* result)
{
if(result->secure) return "(secure)";
if(result->bogus) return "(BOGUS (security failure))";
return "(insecure)";
}
/** nice string for type */
static void
pretty_type(char* s, size_t len, int t)
{
char d[16];
sldns_wire2str_type_buf((uint16_t)t, d, sizeof(d));
snprintf(s, len, "%s", d);
}
/** nice string for class */
static void
pretty_class(char* s, size_t len, int c)
{
char d[16];
sldns_wire2str_class_buf((uint16_t)c, d, sizeof(d));
snprintf(s, len, "%s", d);
}
/** nice string for rcode */
static void
pretty_rcode(char* s, size_t len, int r)
{
char d[16];
sldns_wire2str_rcode_buf(r, d, sizeof(d));
snprintf(s, len, "%s", d);
}
/** convert and print rdata */
static void
print_rd(int t, char* data, size_t len)
{
char s[65535];
sldns_wire2str_rdata_buf((uint8_t*)data, len, s, sizeof(s), (uint16_t)t);
printf(" %s", s);
}
/** pretty line of RR data for results */
static void
pretty_rdata(char* q, char* cstr, char* tstr, int t, const char* sec,
char* data, size_t len)
{
printf("%s", q);
if(strcmp(cstr, "IN") != 0)
printf(" in class %s", cstr);
if(t == LDNS_RR_TYPE_A)
printf(" has address");
else if(t == LDNS_RR_TYPE_AAAA)
printf(" has IPv6 address");
else if(t == LDNS_RR_TYPE_MX)
printf(" mail is handled by");
else if(t == LDNS_RR_TYPE_PTR)
printf(" domain name pointer");
else printf(" has %s record", tstr);
print_rd(t, data, len);
if(verb > 0)
printf(" %s", sec);
printf("\n");
}
/** pretty line of output for results */
static void
pretty_output(char* q, int t, int c, struct ub_result* result, int docname)
{
int i;
const char *secstatus = secure_str(result);
char tstr[16];
char cstr[16];
char rcodestr[16];
pretty_type(tstr, 16, t);
pretty_class(cstr, 16, c);
pretty_rcode(rcodestr, 16, result->rcode);
if(!result->havedata && result->rcode) {
printf("Host %s not found: %d(%s).",
q, result->rcode, rcodestr);
if(verb > 0)
printf(" %s", secstatus);
printf("\n");
if(result->bogus && result->why_bogus)
printf("%s\n", result->why_bogus);
return;
}
if(docname && result->canonname &&
result->canonname != result->qname) {
printf("%s is an alias for %s", result->qname,
result->canonname);
if(verb > 0)
printf(" %s", secstatus);
printf("\n");
}
/* remove trailing . from long canonnames for nicer output */
if(result->canonname && strlen(result->canonname) > 1 &&
result->canonname[strlen(result->canonname)-1] == '.')
result->canonname[strlen(result->canonname)-1] = 0;
if(!result->havedata) {
if(verb > 0) {
printf("%s", result->canonname?result->canonname:q);
if(strcmp(cstr, "IN") != 0)
printf(" in class %s", cstr);
if(t == LDNS_RR_TYPE_A)
printf(" has no address");
else if(t == LDNS_RR_TYPE_AAAA)
printf(" has no IPv6 address");
else if(t == LDNS_RR_TYPE_PTR)
printf(" has no domain name ptr");
else if(t == LDNS_RR_TYPE_MX)
printf(" has no mail handler record");
else if(t == LDNS_RR_TYPE_ANY) {
char* s = sldns_wire2str_pkt(
result->answer_packet,
(size_t)result->answer_len);
if(!s) {
fprintf(stderr, "alloc failure\n");
exit(1);
}
printf("%s\n", s);
} else printf(" has no %s record", tstr);
printf(" %s\n", secstatus);
}
/* else: emptiness to indicate no data */
if(result->bogus && result->why_bogus)
printf("%s\n", result->why_bogus);
return;
}
i=0;
while(result->data[i])
{
pretty_rdata(
result->canonname?result->canonname:q,
cstr, tstr, t, secstatus, result->data[i],
(size_t)result->len[i]);
i++;
}
if(result->bogus && result->why_bogus)
printf("%s\n", result->why_bogus);
}
/** perform a lookup and printout return if domain existed */
static int
dnslook(struct ub_ctx* ctx, char* q, int t, int c, int docname)
{
int ret;
struct ub_result* result;
ret = ub_resolve(ctx, q, t, c, &result);
if(ret != 0) {
fprintf(stderr, "resolve error: %s\n", ub_strerror(ret));
exit(1);
}
pretty_output(q, t, c, result, docname);
ret = result->nxdomain;
ub_resolve_free(result);
return ret;
}
/** perform host lookup */
static void
lookup(struct ub_ctx* ctx, const char* nm, const char* qt, const char* qc)
{
/* massage input into a query name, type and class */
int multi = 0; /* no type, so do A, AAAA, MX */
int reverse = 0; /* we are doing a reverse lookup */
char* realq = massage_qname(nm, &reverse);
int t = massage_type(qt, reverse, &multi);
int c = massage_class(qc);
/* perform the query */
if(multi) {
if(!dnslook(ctx, realq, LDNS_RR_TYPE_A, c, 1)) {
/* domain exists, lookup more */
(void)dnslook(ctx, realq, LDNS_RR_TYPE_AAAA, c, 0);
(void)dnslook(ctx, realq, LDNS_RR_TYPE_MX, c, 0);
}
} else {
(void)dnslook(ctx, realq, t, c, 1);
}
ub_ctx_delete(ctx);
free(realq);
}
/** print error if any */
static void
check_ub_res(int r)
{
if(r != 0) {
fprintf(stderr, "error: %s\n", ub_strerror(r));
exit(1);
}
}
/** getopt global, in case header files fail to declare it. */
extern int optind;
/** getopt global, in case header files fail to declare it. */
extern char* optarg;
/** Main routine for unbound-host */
int main(int argc, char* argv[])
{
int c;
char* qclass = NULL;
char* qtype = NULL;
struct ub_ctx* ctx = NULL;
int debuglevel = 0;
ctx = ub_ctx_create();
if(!ctx) {
fprintf(stderr, "error: out of memory\n");
exit(1);
}
/* no need to fetch additional targets, we only do few lookups */
check_ub_res(ub_ctx_set_option(ctx, "target-fetch-policy:", "0 0 0 0 0"));
/* parse the options */
while( (c=getopt(argc, argv, "46DF:c:df:hrt:vy:C:")) != -1) {
switch(c) {
case '4':
check_ub_res(ub_ctx_set_option(ctx, "do-ip6:", "no"));
break;
case '6':
check_ub_res(ub_ctx_set_option(ctx, "do-ip4:", "no"));
break;
case 'c':
qclass = optarg;
break;
case 'C':
check_ub_res(ub_ctx_config(ctx, optarg));
break;
case 'D':
check_ub_res(ub_ctx_add_ta_file(ctx, ROOT_ANCHOR_FILE));
break;
case 'd':
debuglevel++;
if(debuglevel < 2)
debuglevel = 2; /* at least VERB_DETAIL */
break;
case 'r':
check_ub_res(ub_ctx_resolvconf(ctx, "/etc/resolv.conf"));
break;
case 't':
qtype = optarg;
break;
case 'v':
verb++;
break;
case 'y':
check_ub_res(ub_ctx_add_ta(ctx, optarg));
break;
case 'f':
check_ub_res(ub_ctx_add_ta_file(ctx, optarg));
break;
case 'F':
check_ub_res(ub_ctx_trustedkeys(ctx, optarg));
break;
case '?':
case 'h':
default:
usage();
}
}
if(debuglevel != 0) /* set after possible -C options */
check_ub_res(ub_ctx_debuglevel(ctx, debuglevel));
if(ub_ctx_get_option(ctx, "use-syslog", &optarg) == 0) {
if(strcmp(optarg, "yes") == 0) /* disable use-syslog */
check_ub_res(ub_ctx_set_option(ctx,
"use-syslog:", "no"));
free(optarg);
}
argc -= optind;
argv += optind;
if(argc != 1)
usage();
#ifdef HAVE_NSS
if(NSS_NoDB_Init(".") != SECSuccess) {
fprintf(stderr, "could not init NSS\n");
return 1;
}
#endif
lookup(ctx, argv[0], qtype, qclass);
return 0;
}
