/* $NetBSD: host.c,v 1.14 2025/05/21 14:47:35 christos Exp $ */ /* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * SPDX-License-Identifier: MPL-2.0 * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, you can obtain one at https://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ /*! \file */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dighost.h" static bool short_form = true, listed_server = false; static bool default_lookups = true; static int seen_error = -1; static bool list_addresses = true; static bool list_almost_all = false; static dns_rdatatype_t list_type = dns_rdatatype_a; static bool printed_server = false; static bool ipv4only = false, ipv6only = false; static const char *opcodetext[] = { "QUERY", "IQUERY", "STATUS", "RESERVED3", "NOTIFY", "UPDATE", "RESERVED6", "RESERVED7", "RESERVED8", "RESERVED9", "RESERVED10", "RESERVED11", "RESERVED12", "RESERVED13", "RESERVED14", "RESERVED15" }; static const char *rcodetext[] = { "NOERROR", "FORMERR", "SERVFAIL", "NXDOMAIN", "NOTIMP", "REFUSED", "YXDOMAIN", "YXRRSET", "NXRRSET", "NOTAUTH", "NOTZONE", "RESERVED11", "RESERVED12", "RESERVED13", "RESERVED14", "RESERVED15", "BADVERS" }; struct rtype { unsigned int type; const char *text; }; struct rtype rtypes[] = { { 1, "has address" }, { 2, "name server" }, { 5, "is an alias for" }, { 11, "has well known services" }, { 12, "domain name pointer" }, { 13, "host information" }, { 15, "mail is handled by" }, { 16, "descriptive text" }, { 19, "x25 address" }, { 20, "ISDN address" }, { 24, "has signature" }, { 25, "has key" }, { 28, "has IPv6 address" }, { 29, "location" }, { dns_rdatatype_https, "has HTTP service bindings" }, { 0, NULL } }; static char * rcode_totext(dns_rcode_t rcode) { static char buf[sizeof("?65535")]; union { const char *consttext; char *deconsttext; } totext; if (rcode >= (sizeof(rcodetext) / sizeof(rcodetext[0]))) { snprintf(buf, sizeof(buf), "?%u", rcode); totext.deconsttext = buf; } else { totext.consttext = rcodetext[rcode]; } return totext.deconsttext; } noreturn static void show_usage(void); static void show_usage(void) { fprintf(stderr, "Usage: host [-aCdilrTvVw] [-c class] [-N ndots] [-t type] [-W " "time]\n" " [-R number] [-m flag] [-p port] hostname " "[server]\n" " -a is equivalent to -v -t ANY\n" " -A is like -a but omits RRSIG, NSEC, NSEC3\n" " -c specifies query class for non-IN data\n" " -C compares SOA records on authoritative nameservers\n" " -d is equivalent to -v\n" " -l lists all hosts in a domain, using AXFR\n" " -m set memory debugging flag (trace|record|usage)\n" " -N changes the number of dots allowed before root " "lookup " "is done\n" " -p specifies the port on the server to query\n" " -r disables recursive processing\n" " -R specifies number of retries for UDP packets\n" " -s a SERVFAIL response should stop query\n" " -t specifies the query type\n" " -T enables TCP/IP mode\n" " -U enables UDP mode\n" " -v enables verbose output\n" " -V print version number and exit\n" " -w specifies to wait forever for a reply\n" " -W specifies how long to wait for a reply\n" " -4 use IPv4 query transport only\n" " -6 use IPv6 query transport only\n"); exit(EXIT_FAILURE); } static void host_shutdown(void) { isc_loopmgr_shutdown(loopmgr); } static void received(unsigned int bytes, isc_sockaddr_t *from, dig_query_t *query) { isc_time_t now; int diff; if (!short_form) { char fromtext[ISC_SOCKADDR_FORMATSIZE]; isc_sockaddr_format(from, fromtext, sizeof(fromtext)); if (query->lookup->use_usec) { now = isc_time_now_hires(); } else { now = isc_time_now(); } diff = (int)isc_time_microdiff(&now, &query->time_sent); printf("Received %u bytes from %s in %d ms\n", bytes, fromtext, diff / 1000); } } static void trying(char *frm, dig_lookup_t *lookup) { UNUSED(lookup); if (!short_form) { printf("Trying \"%s\"\n", frm); } } static void say_message(dns_name_t *name, const char *msg, dns_rdata_t *rdata, dig_query_t *query) { isc_buffer_t *b = NULL; char namestr[DNS_NAME_FORMATSIZE]; isc_region_t r; isc_result_t result; unsigned int bufsize = BUFSIZ; dns_name_format(name, namestr, sizeof(namestr)); retry: isc_buffer_allocate(mctx, &b, bufsize); result = dns_rdata_totext(rdata, NULL, b); if (result == ISC_R_NOSPACE) { isc_buffer_free(&b); INSIST(bufsize <= (UINT_MAX / 2)); bufsize *= 2; goto retry; } check_result(result, "dns_rdata_totext"); isc_buffer_usedregion(b, &r); if (query->lookup->identify_previous_line) { printf("Nameserver %s:\n\t", query->servname); } printf("%s %s %.*s", namestr, msg, (int)r.length, (char *)r.base); if (query->lookup->identify) { printf(" on server %s", query->servname); } printf("\n"); isc_buffer_free(&b); } static isc_result_t printsection(dns_message_t *msg, dns_section_t sectionid, const char *section_name, bool headers, dig_query_t *query) { dns_name_t *name, *print_name; dns_rdataset_t *rdataset; dns_rdata_t rdata = DNS_RDATA_INIT; isc_buffer_t target; isc_result_t result, loopresult; isc_region_t r; dns_name_t empty_name; char tbuf[4096] = { 0 }; bool first; bool no_rdata = (sectionid == DNS_SECTION_QUESTION); if (headers) { printf(";; %s SECTION:\n", section_name); } dns_name_init(&empty_name, NULL); result = dns_message_firstname(msg, sectionid); if (result == ISC_R_NOMORE) { return ISC_R_SUCCESS; } else if (result != ISC_R_SUCCESS) { return result; } for (;;) { name = NULL; dns_message_currentname(msg, sectionid, &name); isc_buffer_init(&target, tbuf, sizeof(tbuf)); first = true; print_name = name; for (rdataset = ISC_LIST_HEAD(name->list); rdataset != NULL; rdataset = ISC_LIST_NEXT(rdataset, link)) { if (query->lookup->rdtype == dns_rdatatype_axfr && !((!list_addresses && (list_type == dns_rdatatype_any || rdataset->type == list_type)) || (list_addresses && (rdataset->type == dns_rdatatype_a || rdataset->type == dns_rdatatype_aaaa || rdataset->type == dns_rdatatype_ns || rdataset->type == dns_rdatatype_ptr)))) { continue; } if (list_almost_all && (rdataset->type == dns_rdatatype_rrsig || rdataset->type == dns_rdatatype_nsec || rdataset->type == dns_rdatatype_nsec3)) { continue; } if (!short_form) { result = dns_rdataset_totext(rdataset, print_name, false, no_rdata, &target); if (result != ISC_R_SUCCESS) { return result; } #ifdef USEINITALWS if (first) { print_name = &empty_name; first = false; } #else /* ifdef USEINITALWS */ UNUSED(first); /* Shut up compiler. */ #endif /* ifdef USEINITALWS */ } else { loopresult = dns_rdataset_first(rdataset); while (loopresult == ISC_R_SUCCESS) { struct rtype *t; const char *rtt; char typebuf[DNS_RDATATYPE_FORMATSIZE]; char typebuf2[DNS_RDATATYPE_FORMATSIZE + 20]; dns_rdataset_current(rdataset, &rdata); for (t = rtypes; t->text != NULL; t++) { if (t->type == rdata.type) { rtt = t->text; goto found; } } dns_rdatatype_format(rdata.type, typebuf, sizeof(typebuf)); snprintf(typebuf2, sizeof(typebuf2), "has %s record", typebuf); rtt = typebuf2; found: say_message(print_name, rtt, &rdata, query); dns_rdata_reset(&rdata); loopresult = dns_rdataset_next(rdataset); } } } if (!short_form) { isc_buffer_usedregion(&target, &r); if (no_rdata) { printf(";%.*s", (int)r.length, (char *)r.base); } else { printf("%.*s", (int)r.length, (char *)r.base); } } result = dns_message_nextname(msg, sectionid); if (result == ISC_R_NOMORE) { break; } else if (result != ISC_R_SUCCESS) { return result; } } return ISC_R_SUCCESS; } static isc_result_t printrdata(dns_message_t *msg, dns_rdataset_t *rdataset, const dns_name_t *owner, const char *set_name, bool headers) { isc_buffer_t target; isc_result_t result; isc_region_t r; char tbuf[4096]; UNUSED(msg); if (headers) { printf(";; %s SECTION:\n", set_name); } isc_buffer_init(&target, tbuf, sizeof(tbuf)); result = dns_rdataset_totext(rdataset, owner, false, false, &target); if (result != ISC_R_SUCCESS) { return result; } isc_buffer_usedregion(&target, &r); printf("%.*s", (int)r.length, (char *)r.base); return ISC_R_SUCCESS; } static void chase_cnamechain(dns_message_t *msg, dns_name_t *qname) { isc_result_t result; dns_rdataset_t *rdataset; dns_rdata_cname_t cname; dns_rdata_t rdata = DNS_RDATA_INIT; unsigned int i = msg->counts[DNS_SECTION_ANSWER]; while (i-- > 0) { rdataset = NULL; result = dns_message_findname(msg, DNS_SECTION_ANSWER, qname, dns_rdatatype_cname, 0, NULL, &rdataset); if (result != ISC_R_SUCCESS) { return; } result = dns_rdataset_first(rdataset); check_result(result, "dns_rdataset_first"); dns_rdata_reset(&rdata); dns_rdataset_current(rdataset, &rdata); result = dns_rdata_tostruct(&rdata, &cname, NULL); check_result(result, "dns_rdata_tostruct"); dns_name_copy(&cname.cname, qname); dns_rdata_freestruct(&cname); } } static isc_result_t printmessage(dig_query_t *query, const isc_buffer_t *msgbuf, dns_message_t *msg, bool headers) { bool did_flag = false; dns_rdataset_t *opt, *tsig = NULL; const dns_name_t *tsigname; isc_result_t result = ISC_R_SUCCESS; int force_error; UNUSED(msgbuf); UNUSED(headers); /* * We get called multiple times. * Preserve any existing error status. */ force_error = (seen_error == 1) ? 1 : 0; seen_error = 1; if (listed_server && !printed_server) { char sockstr[ISC_SOCKADDR_FORMATSIZE]; printf("Using domain server:\n"); printf("Name: %s\n", query->userarg); isc_sockaddr_format(&query->sockaddr, sockstr, sizeof(sockstr)); printf("Address: %s\n", sockstr); printf("Aliases: \n\n"); printed_server = true; } if (msg->rcode != 0) { char namestr[DNS_NAME_FORMATSIZE]; dns_name_format(query->lookup->name, namestr, sizeof(namestr)); if (query->lookup->identify_previous_line) { printf("Nameserver %s:\n\t%s not found: %d(%s)\n", query->servname, (msg->rcode != dns_rcode_nxdomain) ? namestr : query->lookup->textname, msg->rcode, rcode_totext(msg->rcode)); } else { printf("Host %s not found: %d(%s)\n", (msg->rcode != dns_rcode_nxdomain) ? namestr : query->lookup->textname, msg->rcode, rcode_totext(msg->rcode)); } return ISC_R_SUCCESS; } if (default_lookups && query->lookup->rdtype == dns_rdatatype_a) { char namestr[DNS_NAME_FORMATSIZE]; dig_lookup_t *lookup; dns_fixedname_t fixed; dns_name_t *name; /* Add AAAA and MX lookups. */ name = dns_fixedname_initname(&fixed); dns_name_copy(query->lookup->name, name); chase_cnamechain(msg, name); dns_name_format(name, namestr, sizeof(namestr)); lookup = clone_lookup(query->lookup, false); if (lookup != NULL) { strlcpy(lookup->textname, namestr, sizeof(lookup->textname)); lookup->rdtype = dns_rdatatype_aaaa; lookup->rdtypeset = true; lookup->origin = NULL; lookup->retries = tries; ISC_LIST_APPEND(lookup_list, lookup, link); } lookup = clone_lookup(query->lookup, false); if (lookup != NULL) { strlcpy(lookup->textname, namestr, sizeof(lookup->textname)); lookup->rdtype = dns_rdatatype_mx; lookup->rdtypeset = true; lookup->origin = NULL; lookup->retries = tries; ISC_LIST_APPEND(lookup_list, lookup, link); } lookup = clone_lookup(query->lookup, false); if (lookup != NULL) { strlcpy(lookup->textname, namestr, sizeof(lookup->textname)); lookup->rdtype = dns_rdatatype_https; lookup->rdtypeset = true; lookup->origin = NULL; lookup->retries = tries; ISC_LIST_APPEND(lookup_list, lookup, link); } } if (!short_form) { printf(";; ->>HEADER<<- opcode: %s, status: %s, id: %u\n", opcodetext[msg->opcode], rcode_totext(msg->rcode), msg->id); printf(";; flags: "); if ((msg->flags & DNS_MESSAGEFLAG_QR) != 0) { printf("qr"); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_AA) != 0) { printf("%saa", did_flag ? " " : ""); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_TC) != 0) { printf("%stc", did_flag ? " " : ""); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_RD) != 0) { printf("%srd", did_flag ? " " : ""); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_RA) != 0) { printf("%sra", did_flag ? " " : ""); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_AD) != 0) { printf("%sad", did_flag ? " " : ""); did_flag = true; } if ((msg->flags & DNS_MESSAGEFLAG_CD) != 0) { printf("%scd", did_flag ? " " : ""); did_flag = true; POST(did_flag); } printf("; QUERY: %u, ANSWER: %u, " "AUTHORITY: %u, ADDITIONAL: %u\n", msg->counts[DNS_SECTION_QUESTION], msg->counts[DNS_SECTION_ANSWER], msg->counts[DNS_SECTION_AUTHORITY], msg->counts[DNS_SECTION_ADDITIONAL]); opt = dns_message_getopt(msg); if (opt != NULL) { printf(";; EDNS: version: %u, udp=%u\n", (unsigned int)((opt->ttl & 0x00ff0000) >> 16), (unsigned int)opt->rdclass); } tsigname = NULL; tsig = dns_message_gettsig(msg, &tsigname); if (tsig != NULL) { printf(";; PSEUDOSECTIONS: TSIG\n"); } } if (!ISC_LIST_EMPTY(msg->sections[DNS_SECTION_QUESTION]) && !short_form) { printf("\n"); result = printsection(msg, DNS_SECTION_QUESTION, "QUESTION", true, query); if (result != ISC_R_SUCCESS) { return result; } } if (!ISC_LIST_EMPTY(msg->sections[DNS_SECTION_ANSWER])) { if (!short_form) { printf("\n"); } result = printsection(msg, DNS_SECTION_ANSWER, "ANSWER", !short_form, query); if (result != ISC_R_SUCCESS) { return result; } } if (!ISC_LIST_EMPTY(msg->sections[DNS_SECTION_AUTHORITY]) && !short_form) { printf("\n"); result = printsection(msg, DNS_SECTION_AUTHORITY, "AUTHORITY", true, query); if (result != ISC_R_SUCCESS) { return result; } } if (!ISC_LIST_EMPTY(msg->sections[DNS_SECTION_ADDITIONAL]) && !short_form) { printf("\n"); result = printsection(msg, DNS_SECTION_ADDITIONAL, "ADDITIONAL", true, query); if (result != ISC_R_SUCCESS) { return result; } } if ((tsig != NULL) && !short_form) { printf("\n"); result = printrdata(msg, tsig, tsigname, "PSEUDOSECTION TSIG", true); if (result != ISC_R_SUCCESS) { return result; } } if (!short_form) { printf("\n"); } if (short_form && !default_lookups && ISC_LIST_EMPTY(msg->sections[DNS_SECTION_ANSWER])) { char namestr[DNS_NAME_FORMATSIZE]; char typestr[DNS_RDATATYPE_FORMATSIZE]; dns_name_format(query->lookup->name, namestr, sizeof(namestr)); dns_rdatatype_format(query->lookup->rdtype, typestr, sizeof(typestr)); printf("%s has no %s record\n", namestr, typestr); } seen_error = force_error; return result; } static const char *optstring = "46aAc:dilnm:p:rst:vVwCDN:R:TUW:"; static void pre_parse_args(int argc, char **argv) { int c; while ((c = isc_commandline_parse(argc, argv, optstring)) != -1) { switch (c) { case 'm': memdebugging = true; if (strcasecmp("trace", isc_commandline_argument) == 0) { isc_mem_debugging |= ISC_MEM_DEBUGTRACE; } else if (strcasecmp("record", isc_commandline_argument) == 0) { isc_mem_debugging |= ISC_MEM_DEBUGRECORD; } else if (strcasecmp("usage", isc_commandline_argument) == 0) { isc_mem_debugging |= ISC_MEM_DEBUGUSAGE; } break; case '4': if (ipv6only) { fatal("only one of -4 and -6 allowed"); } ipv4only = true; break; case '6': if (ipv4only) { fatal("only one of -4 and -6 allowed"); } ipv6only = true; break; case 'a': break; case 'A': break; case 'c': break; case 'C': break; case 'd': break; case 'D': if (debugging) { debugtiming = true; } debugging = true; break; case 'i': break; case 'l': break; case 'n': break; case 'N': break; case 'p': break; case 'r': break; case 'R': break; case 's': break; case 't': break; case 'T': break; case 'U': break; case 'v': break; case 'V': printf("host %s\n", PACKAGE_VERSION); exit(EXIT_SUCCESS); break; case 'w': break; case 'W': break; default: show_usage(); } } isc_commandline_reset = true; isc_commandline_index = 1; } static void parse_args(bool is_batchfile, int argc, char **argv) { char hostname[MXNAME]; dig_lookup_t *lookup; int c; char store[MXNAME]; isc_textregion_t tr; isc_result_t result = ISC_R_SUCCESS; dns_rdatatype_t rdtype; dns_rdataclass_t rdclass; uint32_t serial = 0; UNUSED(is_batchfile); lookup = make_empty_lookup(); lookup->servfail_stops = false; lookup->besteffort = false; lookup->comments = false; short_form = !verbose; while ((c = isc_commandline_parse(argc, argv, optstring)) != -1) { switch (c) { case 'l': lookup->tcp_mode = true; lookup->rdtype = dns_rdatatype_axfr; lookup->rdtypeset = true; fatalexit = 3; break; case 'v': case 'd': short_form = false; break; case 'r': lookup->recurse = false; break; case 't': if (strncasecmp(isc_commandline_argument, "ixfr=", 5) == 0) { rdtype = dns_rdatatype_ixfr; /* XXXMPA add error checking */ serial = strtoul(isc_commandline_argument + 5, NULL, 10); result = ISC_R_SUCCESS; } else { tr.base = isc_commandline_argument; tr.length = strlen(isc_commandline_argument); result = dns_rdatatype_fromtext( &rdtype, (isc_textregion_t *)&tr); } if (result != ISC_R_SUCCESS) { fatalexit = 2; fatal("invalid type: %s\n", isc_commandline_argument); } if (!lookup->rdtypeset || lookup->rdtype != dns_rdatatype_axfr) { lookup->rdtype = rdtype; } lookup->rdtypeset = true; if (rdtype == dns_rdatatype_axfr) { /* -l -t any -v */ list_type = dns_rdatatype_any; short_form = false; lookup->tcp_mode = true; } else if (rdtype == dns_rdatatype_ixfr) { lookup->ixfr_serial = serial; lookup->tcp_mode = true; list_type = rdtype; } else if (rdtype == dns_rdatatype_any) { if (!lookup->tcp_mode_set) { lookup->tcp_mode = true; } } else { list_type = rdtype; } list_addresses = false; default_lookups = false; break; case 'c': tr.base = isc_commandline_argument; tr.length = strlen(isc_commandline_argument); result = dns_rdataclass_fromtext( &rdclass, (isc_textregion_t *)&tr); if (result != ISC_R_SUCCESS) { fatalexit = 2; fatal("invalid class: %s\n", isc_commandline_argument); } else { lookup->rdclass = rdclass; lookup->rdclassset = true; } default_lookups = false; break; case 'A': list_almost_all = true; FALLTHROUGH; case 'a': if (!lookup->rdtypeset || lookup->rdtype != dns_rdatatype_axfr) { lookup->rdtype = dns_rdatatype_any; } list_type = dns_rdatatype_any; list_addresses = false; lookup->rdtypeset = true; short_form = false; default_lookups = false; break; case 'i': /* deprecated */ break; case 'n': /* deprecated */ break; case 'm': /* Handled by pre_parse_args(). */ break; case 'w': /* * The timer routines are coded such that * timeout==MAXINT doesn't enable the timer */ timeout = INT_MAX; break; case 'W': timeout = atoi(isc_commandline_argument); if (timeout < 1) { timeout = 1; } break; case 'R': tries = atoi(isc_commandline_argument) + 1; if (tries < 2) { tries = 2; } break; case 'T': lookup->tcp_mode = true; lookup->tcp_mode_set = true; break; case 'U': lookup->tcp_mode = false; lookup->tcp_mode_set = true; break; case 'C': debug("showing all SOAs"); lookup->rdtype = dns_rdatatype_ns; lookup->rdtypeset = true; lookup->rdclass = dns_rdataclass_in; lookup->rdclassset = true; lookup->ns_search_only = true; lookup->trace_root = true; lookup->identify_previous_line = true; default_lookups = false; break; case 'N': debug("setting NDOTS to %s", isc_commandline_argument); ndots = atoi(isc_commandline_argument); break; case 'D': /* Handled by pre_parse_args(). */ break; case '4': /* Handled by pre_parse_args(). */ break; case '6': /* Handled by pre_parse_args(). */ break; case 's': lookup->servfail_stops = true; break; case 'p': port = atoi(isc_commandline_argument); port_set = true; break; } } lookup->retries = tries; if (isc_commandline_index >= argc) { show_usage(); } strlcpy(hostname, argv[isc_commandline_index], sizeof(hostname)); if (argc > isc_commandline_index + 1) { set_nameserver(argv[isc_commandline_index + 1]); debug("server is %s", argv[isc_commandline_index + 1]); listed_server = true; } else { check_ra = true; } lookup->pending = false; if (get_reverse(store, sizeof(store), hostname, true) == ISC_R_SUCCESS) { strlcpy(lookup->textname, store, sizeof(lookup->textname)); lookup->rdtype = dns_rdatatype_ptr; lookup->rdtypeset = true; default_lookups = false; } else { strlcpy(lookup->textname, hostname, sizeof(lookup->textname)); usesearch = true; } lookup->new_search = true; ISC_LIST_APPEND(lookup_list, lookup, link); } int main(int argc, char **argv) { tries = 2; ISC_LIST_INIT(lookup_list); ISC_LIST_INIT(server_list); ISC_LIST_INIT(search_list); fatalexit = 1; /* setup dighost callbacks */ dighost_printmessage = printmessage; dighost_received = received; dighost_trying = trying; dighost_shutdown = host_shutdown; debug("main()"); progname = argv[0]; pre_parse_args(argc, argv); setup_libs(); setup_system(ipv4only, ipv6only); parse_args(false, argc, argv); if (keyfile[0] != 0) { setup_file_key(); } else if (keysecret[0] != 0) { setup_text_key(); } isc_loopmgr_setup(loopmgr, run_loop, NULL); isc_loopmgr_run(loopmgr); cancel_all(); destroy_libs(); return (seen_error == 0) ? 0 : 1; }