/*
 * Copyright (C) 2000, 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.
 */

/* $Id: host.c,v 1.66 2001/03/14 18:08:17 bwelling Exp $ */

#include <config.h>
#include <stdlib.h>
#include <limits.h>

extern int h_errno;

#include <isc/app.h>
#include <isc/commandline.h>
#include <isc/netaddr.h>
#include <isc/string.h>
#include <isc/util.h>
#include <isc/task.h>

#include <dns/byaddr.h>
#include <dns/fixedname.h>
#include <dns/message.h>
#include <dns/name.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdataset.h>
#include <dns/rdatatype.h>

#include <dig/dig.h>

extern ISC_LIST(dig_lookup_t) lookup_list;
extern ISC_LIST(dig_server_t) server_list;
extern ISC_LIST(dig_searchlist_t) search_list;

extern isc_boolean_t usesearch;
extern isc_boolean_t debugging;
extern unsigned int timeout;
extern isc_mem_t *mctx;
extern int ndots;
extern int tries;
extern char *progname;
extern isc_task_t *global_task;

isc_boolean_t short_form = ISC_TRUE, listed_server = ISC_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",
	"NOTIMPL",
	"REFUSED",
	"YXDOMAIN",
	"YXRRSET",
	"NXRRSET",
	"NOTAUTH",
	"NOTZONE",
	"RESERVED11",
	"RESERVED12",
	"RESERVED13",
	"RESERVED14",
	"RESERVED15",
	"BADVERS"
};

static const char *rtypetext[] = {
	"zero",				/* 0 */
	"has address",			/* 1 */
	"name server",			/* 2 */
	"MD",				/* 3 */
	"MF",				/* 4 */
	"is an alias for",		/* 5 */
	"SOA",				/* 6 */
	"MB",				/* 7 */
	"MG",				/* 8 */
	"MR",				/* 9 */
	"NULL",				/* 10 */
	"has well known services",	/* 11 */
	"domain name pointer",		/* 12 */
	"host information",		/* 13 */
	"MINFO",			/* 14 */
	"mail is handled by",	       	/* 15 */
	"text",				/* 16 */
	"RP",				/* 17 */
	"AFSDB",			/* 18 */
	"x25 address",			/* 19 */
	"isdn address",			/* 20 */
	"RT",				/* 21 */
	"NSAP",				/* 22 */
	"NSAP_PTR",			/* 23 */
	"has signature",		/* 24 */
	"has key",			/* 25 */
	"PX",				/* 26 */
	"GPOS",				/* 27 */
	"has AAAA address",		/* 28 */
	"LOC",				/* 29 */
	"has next record",		/* 30 */
	"EID",				/* 31 */
	"NIMLOC",			/* 32 */
	"SRV",				/* 33 */
	"ATMA",				/* 34 */
	"NAPTR",			/* 35 */
	"KX",				/* 36 */
	"CERT",				/* 37 */
	"has v6 address",		/* 38 */
	"DNAME",			/* 39 */
	"has optional information",	/* 41 */
	"has 42 record",       		/* 42 */
	"has 43 record",       		/* 43 */
	"has 44 record",       		/* 44 */
	"has 45 record",       		/* 45 */
	"has 46 record",       		/* 46 */
	"has 47 record",       		/* 47 */
	"has 48 record",       		/* 48 */
	"has 49 record",       		/* 49 */
	"has 50 record",       		/* 50 */
	"has 51 record",       		/* 51 */
	"has 52 record",       		/* 52 */
	"has 53 record",       		/* 53 */
	"has 54 record",       		/* 54 */
	"has 55 record",       		/* 55 */
	"has 56 record",       		/* 56 */
	"has 57 record",       		/* 57 */
	"has 58 record",       		/* 58 */
	"has 59 record",       		/* 59 */
	"has 60 record",       		/* 60 */
	"has 61 record",       		/* 61 */
	"has 62 record",       		/* 62 */
	"has 63 record",       		/* 63 */
	"has 64 record",       		/* 64 */
	"has 65 record",       		/* 65 */
	"has 66 record",       		/* 66 */
	"has 67 record",       		/* 67 */
	"has 68 record",       		/* 68 */
	"has 69 record",       		/* 69 */
	"has 70 record",       		/* 70 */
	"has 71 record",       		/* 71 */
	"has 72 record",       		/* 72 */
	"has 73 record",       		/* 73 */
	"has 74 record",       		/* 74 */
	"has 75 record",       		/* 75 */
	"has 76 record",       		/* 76 */
	"has 77 record",       		/* 77 */
	"has 78 record",       		/* 78 */
	"has 79 record",       		/* 79 */
	"has 80 record",       		/* 80 */
	"has 81 record",       		/* 81 */
	"has 82 record",       		/* 82 */
	"has 83 record",       		/* 83 */
	"has 84 record",       		/* 84 */
	"has 85 record",       		/* 85 */
	"has 86 record",       		/* 86 */
	"has 87 record",       		/* 87 */
	"has 88 record",       		/* 88 */
	"has 89 record",       		/* 89 */
	"has 90 record",       		/* 90 */
	"has 91 record",       		/* 91 */
	"has 92 record",       		/* 92 */
	"has 93 record",       		/* 93 */
	"has 94 record",       		/* 94 */
	"has 95 record",       		/* 95 */
	"has 96 record",       		/* 96 */
	"has 97 record",       		/* 97 */
	"has 98 record",       		/* 98 */
	"has 99 record",       		/* 99 */
	"UINFO",			/* 100 */
	"UID",				/* 101 */
	"GID",				/* 102 */
	"UNSPEC"};			/* 103 */


static void
show_usage(void) {
	fputs(
"Usage: host [-aCdlrTwv] [-c class] [-n] [-N ndots] [-t type] [-W time]\n"
"            [-R number] hostname [server]\n"
"       -a is equivalent to -v -t *\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"
"       -n Use the nibble form of IPv6 reverse lookup\n"
"       -N changes the number of dots allowed before root lookup is done\n"
"       -r disables recursive processing\n"
"       -R specifies number of retries for UDP packets\n"
"       -t specifies the query type\n"
"       -T enables TCP/IP mode\n"
"       -v enables verbose output\n"
"       -w specifies to wait forever for a reply\n"
"       -W specifies how long to wait for a reply\n", stderr);
	exit(1);
}

void
dighost_shutdown(void) {
	isc_app_shutdown();
}

void
received(int bytes, isc_sockaddr_t *from, dig_query_t *query)
{
	isc_time_t now;
	isc_result_t result;
	int diff;

	if (!short_form) {
		char fromtext[ISC_SOCKADDR_FORMATSIZE];
		isc_sockaddr_format(from, fromtext, sizeof(fromtext));
		result = isc_time_now(&now);
		check_result(result, "isc_time_now");
		diff = isc_time_microdiff(&now, &query->time_sent);
		printf("Received %u bytes from %s in %d ms\n",
		       bytes, fromtext, diff/1000);
	}
}

void
trying(int frmsize, char *frm, dig_lookup_t *lookup) {
	UNUSED(lookup);

	if (!short_form)
		printf("Trying \"%.*s\"\n", frmsize, 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, *b2 = NULL;
	isc_region_t r, r2;
	isc_result_t result;

	result = isc_buffer_allocate(mctx, &b, BUFSIZE);
	check_result(result, "isc_buffer_allocate");
	result = isc_buffer_allocate(mctx, &b2, BUFSIZE);
	check_result(result, "isc_buffer_allocate");
	result = dns_name_totext(name, ISC_FALSE, b);
	check_result(result, "dns_name_totext");
	isc_buffer_usedregion(b, &r);
	result = dns_rdata_totext(rdata, NULL, b2);
	check_result(result, "dns_rdata_totext");
	isc_buffer_usedregion(b2, &r2);
	if (query->lookup->identify_previous_line) {
		printf("Nameserver %s:\n\t",
			query->servname);
	}
	printf("%.*s %s %.*s", (int)r.length, (char *)r.base,
	       msg, (int)r2.length, (char *)r2.base);
	if (query->lookup->identify) {
		printf(" on server %s", query->servname);
	}
	printf("\n");
	isc_buffer_free(&b);
	isc_buffer_free(&b2);
}


static isc_result_t
printsection(dns_message_t *msg, dns_section_t sectionid,
	     const char *section_name, isc_boolean_t 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 t[4096];
	isc_boolean_t first;
	isc_boolean_t no_rdata;
	const char *rtt;

	if (sectionid == DNS_SECTION_QUESTION)
		no_rdata = ISC_TRUE;
	else
		no_rdata = ISC_FALSE;

	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, t, sizeof(t));
		first = ISC_TRUE;
		print_name = name;

		for (rdataset = ISC_LIST_HEAD(name->list);
		     rdataset != NULL;
		     rdataset = ISC_LIST_NEXT(rdataset, link)) {
			if (!short_form) {
				result = dns_rdataset_totext(rdataset,
							     print_name,
							     ISC_FALSE,
							     no_rdata,
							     &target);
				if (result != ISC_R_SUCCESS)
					return (result);
#ifdef USEINITALWS
				if (first) {
					print_name = &empty_name;
					first = ISC_FALSE;
				}
#else
				UNUSED(first); /* Shut up compiler. */
#endif
			} else {
				loopresult = dns_rdataset_first(rdataset);
				while (loopresult == ISC_R_SUCCESS) {
					dns_rdataset_current(rdataset, &rdata);
					if (rdata.type <= 103)
						rtt = rtypetext[rdata.type];
					else if (rdata.type == 249)
						rtt = "key";
					else if (rdata.type == 250)
						rtt = "signature";
					else
						rtt = "unknown";
					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, dns_name_t *owner,
	   const char *set_name, isc_boolean_t headers)
{
	isc_buffer_t target;
	isc_result_t result;
	isc_region_t r;
	char t[4096];

	UNUSED(msg);
	if (headers)
		printf(";; %s SECTION:\n", set_name);

	isc_buffer_init(&target, t, sizeof(t));

	result = dns_rdataset_totext(rdataset, owner, ISC_FALSE, ISC_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);
}

isc_result_t
printmessage(dig_query_t *query, dns_message_t *msg, isc_boolean_t headers) {
	isc_boolean_t did_flag = ISC_FALSE;
	dns_rdataset_t *opt, *tsig = NULL;
	dns_name_t *tsigname;
	isc_result_t result = ISC_R_SUCCESS;
	isc_buffer_t *b = NULL;
	isc_region_t r;

	UNUSED(headers);

	/*
	 * Special case. If we're doing an ns_search_only query, but we're
	 * still following pointers, haven't gotten to the real NS records
	 * yet, don't print anything.
	 */
	if (query->lookup->ns_search_only && !query->lookup->ns_search_only_leafnode)
		return (ISC_R_SUCCESS);

	if (listed_server) {
		printf("Using domain server:\n");
		printf("Name: %s\n", query->servname);
		result = isc_buffer_allocate(mctx, &b, MXNAME);
		check_result(result, "isc_buffer_allocate");
		result = isc_sockaddr_totext(&query->sockaddr, b);
		check_result(result, "isc_sockaddr_totext");
		printf("Address: %.*s\n",
		       (int)isc_buffer_usedlength(b),
		       (char*)isc_buffer_base(b));
		isc_buffer_free(&b);
		printf("Aliases: \n\n");
	}

	if (msg->rcode != 0) {
		result = isc_buffer_allocate(mctx, &b, MXNAME);
		check_result(result, "isc_buffer_allocate");
		result = dns_name_totext(query->lookup->name, ISC_FALSE,
					 b);
		check_result(result, "dns_name_totext");
		isc_buffer_usedregion(b, &r);
		printf("Host %.*s not found: %d(%s)\n",
		       (int)r.length, (char *)r.base,
		       msg->rcode, rcodetext[msg->rcode]);
		isc_buffer_free(&b);
		return (ISC_R_SUCCESS);
	}
	if (!short_form) {
		printf(";; ->>HEADER<<- opcode: %s, status: %s, id: %u\n",
		       opcodetext[msg->opcode], rcodetext[msg->rcode],
		       msg->id);
		printf(";; flags: ");
		if ((msg->flags & DNS_MESSAGEFLAG_QR) != 0) {
			printf("qr");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_AA) != 0) {
			printf("%saa", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_TC) != 0) {
			printf("%stc", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_RD) != 0) {
			printf("%srd", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_RA) != 0) {
			printf("%sra", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_AD) != 0) {
			printf("%sad", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		if ((msg->flags & DNS_MESSAGEFLAG_CD) != 0) {
			printf("%scd", did_flag ? " " : "");
			did_flag = ISC_TRUE;
		}
		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",
				      ISC_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",
				      ISC_TF(!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",
				      ISC_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", ISC_TRUE, query);
		if (result != ISC_R_SUCCESS)
			return (result);
	}
	if ((tsig != NULL) && !short_form) {
		printf("\n");
		result = printrdata(msg, tsig, tsigname,
				    "PSEUDOSECTION TSIG", ISC_TRUE);
		if (result != ISC_R_SUCCESS)
			return (result);
	}
	if (!short_form)
		printf("\n");

	return (result);
}

static void
parse_args(isc_boolean_t is_batchfile, int argc, char **argv) {
	char hostname[MXNAME];
	dig_server_t *srv;
	dig_lookup_t *lookup;
	int c;
	char store[MXNAME];
	isc_textregion_t tr;
	isc_result_t result;
	dns_rdatatype_t rdtype;
	dns_rdataclass_t rdclass;

	UNUSED(is_batchfile);

	lookup = make_empty_lookup();

	while ((c = isc_commandline_parse(argc, argv, "lvwrdt:c:aTCN:R:W:Dn"))
	       != EOF) {
		switch (c) {
		case 'l':
			lookup->tcp_mode = ISC_TRUE;
			lookup->rdtype = dns_rdatatype_axfr;
			lookup->rdtypeset = ISC_TRUE;
			break;
		case 'v':
		case 'd':
			short_form = ISC_FALSE;
			break;
		case 'r':
			lookup->recurse = ISC_FALSE;
			break;
		case 't':
			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)
				fprintf(stderr,"Warning: invalid type: %s\n",
					isc_commandline_argument);
			else {
				lookup->rdtype = rdtype;
				lookup->rdtypeset = ISC_TRUE;
			}
			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)
				fprintf(stderr,"Warning: invalid class: %s\n",
					isc_commandline_argument);
			else {
				lookup->rdclass = rdclass;
				lookup->rdclassset = ISC_TRUE;
			}
			break;
		case 'a':
			lookup->rdtype = dns_rdatatype_any;
			lookup->rdtypeset = ISC_TRUE;
			short_form = ISC_FALSE;
			break;
		case 'n':
			lookup->nibble = ISC_TRUE;
			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);
			if (tries < 1)
				tries = 1;
			break;
		case 'T':
			lookup->tcp_mode = ISC_TRUE;
			break;
		case 'C':
			debug("showing all SOAs");
			lookup->rdtype = dns_rdatatype_soa;
			lookup->rdtypeset = ISC_TRUE;
			lookup->rdclass = dns_rdataclass_in;
			lookup->rdclassset = ISC_TRUE;
			lookup->ns_search_only = ISC_TRUE;
			lookup->trace_root = ISC_TRUE;
			lookup->identify_previous_line = ISC_TRUE;
			break;
		case 'N':
			debug("setting NDOTS to %s",
			      isc_commandline_argument);
			ndots = atoi(isc_commandline_argument);
			break;
		case 'D':
			debugging = ISC_TRUE;
			break;
		}
	}
	if (isc_commandline_index >= argc) {
		show_usage();
	}
	strncpy(hostname, argv[isc_commandline_index], sizeof(hostname));
	hostname[sizeof(hostname)-1]=0;
	if (argc > isc_commandline_index + 1) {
		srv = make_server(argv[isc_commandline_index+1]);
		debug("server is %s", srv->servername);
		ISC_LIST_APPEND(server_list, srv, link);
		listed_server = ISC_TRUE;
	}

	lookup->pending = ISC_FALSE;
	if (get_reverse(store, hostname, lookup->nibble) == ISC_R_SUCCESS) {
		strncpy(lookup->textname, store, sizeof(lookup->textname));
		lookup->textname[sizeof(lookup->textname)-1] = 0;
		lookup->rdtype = dns_rdatatype_ptr;
		lookup->rdtypeset = ISC_TRUE;
	} else {
		strncpy(lookup->textname, hostname, sizeof(lookup->textname));
		lookup->textname[sizeof(lookup->textname)-1]=0;
	}
	lookup->new_search = ISC_TRUE;
	ISC_LIST_APPEND(lookup_list, lookup, link);

	usesearch = ISC_TRUE;
}

int
main(int argc, char **argv) {
	isc_result_t result;

	ISC_LIST_INIT(lookup_list);
	ISC_LIST_INIT(server_list);
	ISC_LIST_INIT(search_list);

	debug("main()");
	progname = argv[0];
	result = isc_app_start();
	check_result(result, "isc_app_start");
	setup_libs();
	parse_args(ISC_FALSE, argc, argv);
	setup_system();
	result = isc_app_onrun(mctx, global_task, onrun_callback, NULL);
	check_result(result, "isc_app_onrun");
	isc_app_run();
	cancel_all();
	destroy_libs();
	isc_app_finish();
	return (0);
}

