nsupdate.c

非常好的dns解析软件

/*
 * Copyright (C) 2004-2006  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 2000-2003  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 ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC 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: nsupdate.c,v 1.130.18.15 2006/12/07 05:39:45 marka Exp $ */

/*! \file */

#include <config.h>

#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>

#include <isc/app.h>
#include <isc/base64.h>
#include <isc/buffer.h>
#include <isc/commandline.h>
#include <isc/entropy.h>
#include <isc/event.h>
#include <isc/hash.h>
#include <isc/lex.h>
#include <isc/mem.h>
#include <isc/parseint.h>
#include <isc/region.h>
#include <isc/sockaddr.h>
#include <isc/socket.h>
#include <isc/stdio.h>
#include <isc/string.h>
#include <isc/task.h>
#include <isc/timer.h>
#include <isc/types.h>
#include <isc/util.h>

#include <dns/callbacks.h>
#include <dns/dispatch.h>
#include <dns/dnssec.h>
#include <dns/events.h>
#include <dns/fixedname.h>
#include <dns/masterdump.h>
#include <dns/message.h>
#include <dns/name.h>
#include <dns/rcode.h>
#include <dns/rdata.h>
#include <dns/rdataclass.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatastruct.h>
#include <dns/rdatatype.h>
#include <dns/request.h>
#include <dns/result.h>
#include <dns/tsig.h>

#include <dst/dst.h>

#include <lwres/lwres.h>
#include <lwres/net.h>

#include <bind9/getaddresses.h>

#ifdef HAVE_ADDRINFO
#ifdef HAVE_GETADDRINFO
#ifdef HAVE_GAISTRERROR
#define USE_GETADDRINFO
#endif
#endif
#endif

#ifndef USE_GETADDRINFO
#ifndef ISC_PLATFORM_NONSTDHERRNO
extern int h_errno;
#endif
#endif

#define MAXCMD (4 * 1024)
#define MAXWIRE (64 * 1024)
#define PACKETSIZE ((64 * 1024) - 1)
#define INITTEXT (2 * 1024)
#define MAXTEXT (128 * 1024)
#define FIND_TIMEOUT 5
#define TTL_MAX 2147483647U	/* Maximum signed 32 bit integer. */

#define DNSDEFAULTPORT 53

#ifndef RESOLV_CONF
#define RESOLV_CONF "/etc/resolv.conf"
#endif

static isc_boolean_t debugging = ISC_FALSE, ddebugging = ISC_FALSE;
static isc_boolean_t memdebugging = ISC_FALSE;
static isc_boolean_t have_ipv4 = ISC_FALSE;
static isc_boolean_t have_ipv6 = ISC_FALSE;
static isc_boolean_t is_dst_up = ISC_FALSE;
static isc_boolean_t usevc = ISC_FALSE;
static isc_taskmgr_t *taskmgr = NULL;
static isc_task_t *global_task = NULL;
static isc_event_t *global_event = NULL;
static isc_mem_t *mctx = NULL;
static dns_dispatchmgr_t *dispatchmgr = NULL;
static dns_requestmgr_t *requestmgr = NULL;
static isc_socketmgr_t *socketmgr = NULL;
static isc_timermgr_t *timermgr = NULL;
static dns_dispatch_t *dispatchv4 = NULL;
static dns_dispatch_t *dispatchv6 = NULL;
static dns_message_t *updatemsg = NULL;
static dns_fixedname_t fuserzone;
static dns_name_t *userzone = NULL;
static dns_tsigkey_t *tsigkey = NULL;
static dst_key_t *sig0key;
static lwres_context_t *lwctx = NULL;
static lwres_conf_t *lwconf;
static isc_sockaddr_t *servers;
static int ns_inuse = 0;
static int ns_total = 0;
static isc_sockaddr_t *userserver = NULL;
static isc_sockaddr_t *localaddr = NULL;
static char *keystr = NULL, *keyfile = NULL;
static isc_entropy_t *entp = NULL;
static isc_boolean_t shuttingdown = ISC_FALSE;
static FILE *input;
static isc_boolean_t interactive = ISC_TRUE;
static isc_boolean_t seenerror = ISC_FALSE;
static const dns_master_style_t *style;
static int requests = 0;
static unsigned int timeout = 300;
static unsigned int udp_timeout = 3;
static unsigned int udp_retries = 3;
static dns_rdataclass_t defaultclass = dns_rdataclass_in;
static dns_rdataclass_t zoneclass = dns_rdataclass_none;
static dns_message_t *answer = NULL;

typedef struct nsu_requestinfo {
	dns_message_t *msg;
	isc_sockaddr_t *addr;
} nsu_requestinfo_t;

static void
sendrequest(isc_sockaddr_t *srcaddr, isc_sockaddr_t *destaddr,
	    dns_message_t *msg, dns_request_t **request);
static void
fatal(const char *format, ...) ISC_FORMAT_PRINTF(1, 2);

static void
debug(const char *format, ...) ISC_FORMAT_PRINTF(1, 2);

static void
ddebug(const char *format, ...) ISC_FORMAT_PRINTF(1, 2);

static void
error(const char *format, ...) ISC_FORMAT_PRINTF(1, 2);

#define STATUS_MORE	(isc_uint16_t)0
#define STATUS_SEND	(isc_uint16_t)1
#define STATUS_QUIT	(isc_uint16_t)2
#define STATUS_SYNTAX	(isc_uint16_t)3

static dns_rdataclass_t
getzoneclass(void) {
	if (zoneclass == dns_rdataclass_none)
		zoneclass = defaultclass;
	return (zoneclass);
}

static isc_boolean_t
setzoneclass(dns_rdataclass_t rdclass) {
	if (zoneclass == dns_rdataclass_none ||
	    rdclass == dns_rdataclass_none)
		zoneclass = rdclass;
	if (zoneclass != rdclass)
		return (ISC_FALSE);
	return (ISC_TRUE);
}

static void
fatal(const char *format, ...) {
	va_list args;

	va_start(args, format);
	vfprintf(stderr, format, args);
	va_end(args);
	fprintf(stderr, "\n");
	exit(1);
}

static void
error(const char *format, ...) {
	va_list args;

	va_start(args, format);
	vfprintf(stderr, format, args);
	va_end(args);
	fprintf(stderr, "\n");
}

static void
debug(const char *format, ...) {
	va_list args;

	if (debugging) {
		va_start(args, format);
		vfprintf(stderr, format, args);
		va_end(args);
		fprintf(stderr, "\n");
	}
}

static void
ddebug(const char *format, ...) {
	va_list args;

	if (ddebugging) {
		va_start(args, format);
		vfprintf(stderr, format, args);
		va_end(args);
		fprintf(stderr, "\n");
	}
}

static inline void
check_result(isc_result_t result, const char *msg) {
	if (result != ISC_R_SUCCESS)
		fatal("%s: %s", msg, isc_result_totext(result));
}

static void *
mem_alloc(void *arg, size_t size) {
	return (isc_mem_get(arg, size));
}

static void
mem_free(void *arg, void *mem, size_t size) {
	isc_mem_put(arg, mem, size);
}

static char *
nsu_strsep(char **stringp, const char *delim) {
	char *string = *stringp;
	char *s;
	const char *d;
	char sc, dc;

	if (string == NULL)
		return (NULL);

	for (; *string != '\0'; string++) {
		sc = *string;
		for (d = delim; (dc = *d) != '\0'; d++) {
			if (sc == dc)
				break;
		}
		if (dc == 0)
			break;
	}

	for (s = string; *s != '\0'; s++) {
		sc = *s;
		for (d = delim; (dc = *d) != '\0'; d++) {
			if (sc == dc) {
				*s++ = '\0';
				*stringp = s;
				return (string);
			}
		}
	}
	*stringp = NULL;
	return (string);
}

static void
reset_system(void) {
	isc_result_t result;

	ddebug("reset_system()");
	/* If the update message is still around, destroy it */
	if (updatemsg != NULL)
		dns_message_reset(updatemsg, DNS_MESSAGE_INTENTRENDER);
	else {
		result = dns_message_create(mctx, DNS_MESSAGE_INTENTRENDER,
					    &updatemsg);
		check_result(result, "dns_message_create");
	}
	updatemsg->opcode = dns_opcode_update;
}

static isc_uint16_t
parse_hmac(dns_name_t **hmac, const char *hmacstr, size_t len) {
	isc_uint16_t digestbits = 0;
	isc_result_t result;
	char buf[20];

	REQUIRE(hmac != NULL && *hmac == NULL);
	REQUIRE(hmacstr != NULL);

	if (len >= sizeof(buf))
		fatal("unknown key type '%.*s'", (int)(len), hmacstr);

	strncpy(buf, hmacstr, len);
	buf[len] = 0;
	
	if (strcasecmp(buf, "hmac-md5") == 0) {
		*hmac = DNS_TSIG_HMACMD5_NAME;
	} else if (strncasecmp(buf, "hmac-md5-", 9) == 0) {
		*hmac = DNS_TSIG_HMACMD5_NAME;
		result = isc_parse_uint16(&digestbits, &buf[9], 10);
		if (result != ISC_R_SUCCESS || digestbits > 128)
			fatal("digest-bits out of range [0..128]");
		digestbits = (digestbits +7) & ~0x7U;
	} else if (strcasecmp(buf, "hmac-sha1") == 0) {
		*hmac = DNS_TSIG_HMACSHA1_NAME;
	} else if (strncasecmp(buf, "hmac-sha1-", 10) == 0) {
		*hmac = DNS_TSIG_HMACSHA1_NAME;
		result = isc_parse_uint16(&digestbits, &buf[10], 10);
		if (result != ISC_R_SUCCESS || digestbits > 160)
			fatal("digest-bits out of range [0..160]");
		digestbits = (digestbits +7) & ~0x7U;
	} else if (strcasecmp(buf, "hmac-sha224") == 0) {
		*hmac = DNS_TSIG_HMACSHA224_NAME;
	} else if (strncasecmp(buf, "hmac-sha224-", 12) == 0) {
		*hmac = DNS_TSIG_HMACSHA224_NAME;
		result = isc_parse_uint16(&digestbits, &buf[12], 10);
		if (result != ISC_R_SUCCESS || digestbits > 224)
			fatal("digest-bits out of range [0..224]");
		digestbits = (digestbits +7) & ~0x7U;
	} else if (strcasecmp(buf, "hmac-sha256") == 0) {
		*hmac = DNS_TSIG_HMACSHA256_NAME;
	} else if (strncasecmp(buf, "hmac-sha256-", 12) == 0) {
		*hmac = DNS_TSIG_HMACSHA256_NAME;
		result = isc_parse_uint16(&digestbits, &buf[12], 10);
		if (result != ISC_R_SUCCESS || digestbits > 256)
			fatal("digest-bits out of range [0..256]");
		digestbits = (digestbits +7) & ~0x7U;
	} else if (strcasecmp(buf, "hmac-sha384") == 0) {
		*hmac = DNS_TSIG_HMACSHA384_NAME;
	} else if (strncasecmp(buf, "hmac-sha384-", 12) == 0) {
		*hmac = DNS_TSIG_HMACSHA384_NAME;
		result = isc_parse_uint16(&digestbits, &buf[12], 10);
		if (result != ISC_R_SUCCESS || digestbits > 384)
			fatal("digest-bits out of range [0..384]");
		digestbits = (digestbits +7) & ~0x7U;
	} else if (strcasecmp(buf, "hmac-sha512") == 0) {
		*hmac = DNS_TSIG_HMACSHA512_NAME;
	} else if (strncasecmp(buf, "hmac-sha512-", 12) == 0) {
		*hmac = DNS_TSIG_HMACSHA512_NAME;
		result = isc_parse_uint16(&digestbits, &buf[12], 10);
		if (result != ISC_R_SUCCESS || digestbits > 512)
			fatal("digest-bits out of range [0..512]");
		digestbits = (digestbits +7) & ~0x7U;
	} else
		fatal("unknown key type '%s'", buf);
	return (digestbits);
}

static void
setup_keystr(void) {
	unsigned char *secret = NULL;
	int secretlen;
	isc_buffer_t secretbuf;
	isc_result_t result;
	isc_buffer_t keynamesrc;
	char *secretstr;
	char *s, *n;
	dns_fixedname_t fkeyname;
	dns_name_t *keyname;
	char *name;
	dns_name_t *hmacname = NULL;
	isc_uint16_t digestbits = 0;

	dns_fixedname_init(&fkeyname);
	keyname = dns_fixedname_name(&fkeyname);

	debug("Creating key...");

	s = strchr(keystr, ':');
	if (s == NULL || s == keystr || s[1] == 0)
		fatal("key option must specify [hmac:]keyname:secret");
	secretstr = s + 1;
	n = strchr(secretstr, ':');
	if (n != NULL) {
		if (n == secretstr || n[1] == 0)
			fatal("key option must specify [hmac:]keyname:secret");
		name = secretstr;
		secretstr = n + 1;
		digestbits = parse_hmac(&hmacname, keystr, s - keystr);
	} else {
		hmacname = DNS_TSIG_HMACMD5_NAME;
		name = keystr;
		n = s;
	}

	isc_buffer_init(&keynamesrc, name, n - name);
	isc_buffer_add(&keynamesrc, n - name);

	debug("namefromtext");
	result = dns_name_fromtext(keyname, &keynamesrc, dns_rootname,
				   ISC_FALSE, NULL);
	check_result(result, "dns_name_fromtext");

	secretlen = strlen(secretstr) * 3 / 4;
	secret = isc_mem_allocate(mctx, secretlen);
	if (secret == NULL)
		fatal("out of memory");

	isc_buffer_init(&secretbuf, secret, secretlen);
	result = isc_base64_decodestring(secretstr, &secretbuf);
	if (result != ISC_R_SUCCESS) {
		fprintf(stderr, "could not create key from %s: %s\n",
			keystr, isc_result_totext(result));
		goto failure;
	}

	secretlen = isc_buffer_usedlength(&secretbuf);

	debug("keycreate");
	result = dns_tsigkey_create(keyname, hmacname, secret, secretlen,
				    ISC_TRUE, NULL, 0, 0, mctx, NULL, &tsigkey);
	if (result != ISC_R_SUCCESS)
		fprintf(stderr, "could not create key from %s: %s\n",
			keystr, dns_result_totext(result));
	else
		dst_key_setbits(tsigkey->key, digestbits);
 failure:
	if (secret != NULL)
		isc_mem_free(mctx, secret);
}

static void
setup_keyfile(void) {
	dst_key_t *dstkey = NULL;
	isc_result_t result;
	dns_name_t *hmacname = NULL;

	debug("Creating key...");

	result = dst_key_fromnamedfile(keyfile,
				       DST_TYPE_PRIVATE | DST_TYPE_KEY, mctx,
				       &dstkey);
	if (result != ISC_R_SUCCESS) {
		fprintf(stderr, "could not read key from %s: %s\n",
			keyfile, isc_result_totext(result));
		return;
	}
	switch (dst_key_alg(dstkey)) {
	case DST_ALG_HMACMD5:
		hmacname = DNS_TSIG_HMACMD5_NAME;
		break;
	case DST_ALG_HMACSHA1:
		hmacname = DNS_TSIG_HMACSHA1_NAME;
		break;
	case DST_ALG_HMACSHA224:
		hmacname = DNS_TSIG_HMACSHA224_NAME;
		break;
	case DST_ALG_HMACSHA256:
		hmacname = DNS_TSIG_HMACSHA256_NAME;
		break;
	case DST_ALG_HMACSHA384:
		hmacname = DNS_TSIG_HMACSHA384_NAME;
		break;
	case DST_ALG_HMACSHA512:
		hmacname = DNS_TSIG_HMACSHA512_NAME;
		break;
	}
	if (hmacname != NULL) {
		result = dns_tsigkey_createfromkey(dst_key_name(dstkey),
						   hmacname, dstkey, ISC_FALSE,
						   NULL, 0, 0, mctx, NULL,
						   &tsigkey);
		if (result != ISC_R_SUCCESS) {
			fprintf(stderr, "could not create key from %s: %s\n",
				keyfile, isc_result_totext(result));
			dst_key_free(&dstkey);
			return;
		}
	} else
		sig0key = dstkey;
}

static void
doshutdown(void) {
	isc_task_detach(&global_task);

	if (userserver != NULL)
		isc_mem_put(mctx, userserver, sizeof(isc_sockaddr_t));

	if (localaddr != NULL)
		isc_mem_put(mctx, localaddr, sizeof(isc_sockaddr_t));

	if (tsigkey != NULL) {
		ddebug("Freeing TSIG key");
		dns_tsigkey_detach(&tsigkey);
	}

	if (sig0key != NULL) {
		ddebug("Freeing SIG(0) key");
		dst_key_free(&sig0key);
	}

	if (updatemsg != NULL)
		dns_message_destroy(&updatemsg);

	if (is_dst_up) {
		ddebug("Destroy DST lib");
		dst_lib_destroy();
		is_dst_up = ISC_FALSE;
	}

	if (entp != NULL) {
		ddebug("Detach from entropy");
		isc_entropy_detach(&entp);
	}

	lwres_conf_clear(lwctx);
	lwres_context_destroy(&lwctx);

	isc_mem_put(mctx, servers, ns_total * sizeof(isc_sockaddr_t));

	ddebug("Destroying request manager");
	dns_requestmgr_detach(&requestmgr);

	ddebug("Freeing the dispatchers");
	if (have_ipv4)
		dns_dispatch_detach(&dispatchv4);
	if (have_ipv6)
		dns_dispatch_detach(&dispatchv6);

	ddebug("Shutting down dispatch manager");
	dns_dispatchmgr_destroy(&dispatchmgr);

}