host.c

早期freebsd实现

		if (type == T_A)
			adrname = strcpy(adrnamebuf, rname);
		else if (type == T_NS)
			subname = strcpy(subnamebuf, rname);
		else if (type == T_SOA)
			soaname = strcpy(soanamebuf, rname);
	}

/*
 * Print type specific data, if appropriate.
 */
	switch (type)
	{
	    case T_A:
		switch (class)
		{
		    case C_IN:
		    case C_HS:
			if (dlen == sizeof(ipaddr_t))
			{
				bcopy((char *)cp, (char *)&inaddr, sizeof(inaddr));
				address = inaddr.s_addr;
				doprintf("\t%s", inet_ntoa(inaddr));
				cp += dlen;
				break;
			}
			else if (dlen == sizeof(ipaddr_t) + 3)
			{
				bcopy((char *)cp, (char *)&inaddr, sizeof(inaddr));
				address = inaddr.s_addr;
				doprintf("\t%s", inet_ntoa(inaddr));
				n = cp[4];
				doprintf(", protocol = %s", itoa(n));
				n = (cp[5] << 8) + cp[6];
				doprintf(", port = %s", itoa(n));
				cp += dlen;
				break;
			}
			address = 0;
			break;

		    default:
			address = 0;
			cp += dlen;
			break;
		}
		break;

	    case T_MX:
		if (check_size(rname, type, cp, msg, eor, sizeof(u_short)) < 0)
			break;
		n = _getshort(cp);
		if (verbose || ttlprint)
			doprintf("\t%s ", itoa(n));
		else
			doprintf("\t");
		cp += sizeof(u_short);

		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("%s", pr_name(dname));
		cp += n;
		break;

	    case T_NS:
	    case T_PTR:
	    case T_CNAME:
		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("\t%s", pr_name(dname));
		cp += n;
		break;

	    case T_SOA:
		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("\t%s", pr_name(dname));
		cp += n;

		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf(" %s", pr_name(dname));
		cp += n;

		n = 5*sizeof(u_int);
		if (check_size(rname, type, cp, msg, eor, n) < 0)
			break;
		n = _getlong(cp);
		doprintf(" (\n\t\t\t%s\t;serial (version)", itoa(n));
		cp += sizeof(u_int);
		n = _getlong(cp);
		doprintf("\n\t\t\t%s\t;refresh period", itoa(n));
		cp += sizeof(u_int);
		n = _getlong(cp);
		doprintf("\n\t\t\t%s\t;retry refresh time", itoa(n));
		cp += sizeof(u_int);
		n = _getlong(cp);
		doprintf("\n\t\t\t%s\t;expiration period", itoa(n));
		cp += sizeof(u_int);
		n = _getlong(cp);
		doprintf("\n\t\t\t%s\t;default ttl\n\t\t\t)", itoa(n));
		cp += sizeof(u_int);
		break;

	    case T_WKS:
		if (check_size(rname, type, cp, msg, eor, sizeof(ipaddr_t)) < 0)
			break;
		bcopy((char *)cp, (char *)&inaddr, sizeof(inaddr));
		doprintf("\t%s", inet_ntoa(inaddr));
		cp += sizeof(ipaddr_t);

		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		protocol = getprotobynumber(n);
		if (protocol != NULL)
			doprintf(" %s", protocol->p_name);
		else
			doprintf(" %s", itoa(n));

		doprintf(" (");
		n = 0;
		while (cp < eor)
		{
		    register int c;

		    c = *cp++;
		    do
		    {
 			if (c & 0200)
			{
			    if (protocol != NULL)
				    service = getservbyport(htons(n), protocol->p_name);
			    else
				    service = NULL;
			    if (service != NULL)
				    doprintf(" %s", service->s_name);
			    else
				    doprintf(" %s", itoa(n));
			}
 			c <<= 1;
		    } while (++n & 07);
		}
		doprintf(" )");
		break;

	    case T_HINFO:
		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		doprintf("\t\"%s\"", stoa(cp, n));
		cp += n;

		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		doprintf("\t\"%s\"", stoa(cp, n));
		cp += n;
		break;

	    case T_MINFO:
		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("\t%s", pr_name(dname));
		cp += n;

		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf(" %s", pr_name(dname));
		cp += n;
		break;

	    case T_MB:
	    case T_MG:
	    case T_MR:
	    case T_MD:
	    case T_MF:
		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("\t%s", pr_name(dname));
		cp += n;
		break;

#ifdef obsolete
	    case T_TXT:
		if (dlen > 0)
		{
			doprintf("\t%s", stoa(cp, dlen));
			cp += dlen;
		}
		break;
#endif
	    case T_TXT:
		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		doprintf("\t\"%s", stoa(cp, n));
		cp += n;

		while (cp < eor)
		{
			if (check_size(rname, type, cp, msg, eor, 1) < 0)
				break;
			n = *cp++;
			doprintf("%s", stoa(cp, n));
			cp += n;
		}

		doprintf("\"");
		break;

	    case T_UINFO:
		doprintf("\t\"%s\"", stoa(cp, dlen));
		cp += dlen;
		break;

	    case T_UID:
	    case T_GID:
		if (dlen == sizeof(int))
		{
			n = _getlong(cp);
			doprintf("\t%s", itoa(n));
			cp += dlen;
		}
		break;

	    case T_UNSPEC:
	    case T_NULL:
		cp += dlen;
		break;

	    case T_RP:
		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("\t%s", pr_name(dname));
		cp += n;

		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf(" %s", pr_name(dname));
		cp += n;
		break;

	    case T_RT:
	    case T_AFSDB:
		if (check_size(rname, type, cp, msg, eor, sizeof(u_short)) < 0)
			break;
		n = _getshort(cp);
		if (verbose || ttlprint)
			doprintf("\t%s ", itoa(n));
		else
			doprintf("\t");
		cp += sizeof(u_short);

		n = expand_name(rname, type, cp, msg, eom, dname);
		if (n < 0)
			break;
		doprintf("%s", pr_name(dname));
		cp += n;
		break;

	    case T_X25:
		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		if (n > 0)
		{
			doprintf("\t%s", stoa(cp, n));
			cp += n;
		}
		break;

	    case T_ISDN:
		if (check_size(rname, type, cp, msg, eor, 1) < 0)
			break;
		n = *cp++;
		if (n > 0)
		{
			doprintf("\t%s", stoa(cp, n));
			cp += n;
		}

		if (cp < eor)
		{
			if (check_size(rname, type, cp, msg, eor, 1) < 0)
				break;
			n = *cp++;
			if (n > 0)
			{
				doprintf("\t%s", stoa(cp, n));
				cp += n;
			}
		}
		break;

	    case T_NSAP:
	    case T_NSAPPTR:
		doprintf("\t(not yet implemented)");
		cp += dlen;
		break;

	    default:
		doprintf("\t???");
		cp += dlen;
		break;
	}

	doprintf("\n");

/*
 * Check validity of the name of this resource record.
 * Currently only during zone listing and if requested.
 */
	if (listing && illegal && !valid_name(rname, TRUE))
	{
		pr_warning("illegal %s record name %s",
			pr_type(type), rname);
	}

/*
 * Save the CNAME alias for cname chain tracing.
 * Save the MR or MG alias for MB chain tracing.
 */
	if (!listmode && classmatch)
	{
		if ((type == T_CNAME) && n > 0 && cp == eor)
			cname = strcpy(cnamebuf, dname);
		else if ((type == T_MR || type == T_MG) && n > 0 && cp == eor)
			mname = strcpy(mnamebuf, dname);
	}

/*
 * Check if we have reached the exact end of this record.
 */
	if (cp != eor)
	{
		pr_error("size error in %s record for %s, off by = %s",
			pr_type(type), rname, itoa(cp - eor));

		/* we believe value of dlen; should perhaps return(NULL) */
		cp = eor;
	}

	return(cp);
}

/*
** SKIP_QREC -- Skip the query record in the nameserver answer buffer
** ------------------------------------------------------------------
**
**	Returns:
**		Pointer to position in answer buffer after current record.
**		NULL if there was a format error in the current record.
*/

u_char *
skip_qrec(name, cp, msg, eom)
input char *name;			/* full name we are querying about */
register u_char *cp;			/* current position in answer buf */
input u_char *msg, *eom;		/* begin and end of answer buf */
{
	char rname[MAXDNAME+1];		/* record name in LHS */
	int type, class;		/* fixed values in query record */
	register int n;

	n = expand_name(name, T_NONE, cp, msg, eom, rname);
	if (n < 0)
		return(NULL);
	cp += n;

	n = 2*sizeof(u_short);
	if (check_size(rname, T_NONE, cp, msg, eom, n) < 0)
		return(NULL);

	type = _getshort(cp);
	cp += sizeof(u_short);

	class = _getshort(cp);
	cp += sizeof(u_short);

#ifdef lint
	if (verbose)
		printf("%-20s\t%s\t%s\n",
			rname, pr_class(class), pr_type(type));
#endif
	return(cp);
}


/*
 * Nameserver information.
 * Stores names and addresses of all servers that are to be queried
 * for a zone transfer of the desired zone. Normally these are the
 * authoritative primary and/or secondary nameservers for the zone.
 */

#define MAXNSNAME 16		/* maximum count of nameservers per zone */
#define MAXIPADDR 10		/* maximum count of addresses per nameserver */

char nsname[MAXNSNAME][MAXDNAME+1];		/* nameserver hostname */
struct in_addr ipaddr[MAXNSNAME][MAXIPADDR];	/* nameserver addresses */
int naddrs[MAXNSNAME];				/* count of addresses */
int nservers = 0;				/* count of nameservers */

#ifdef notyet
typedef struct ns_data {
	char nsname[MAXDNAME+1];		/* nameserver hostname */
	struct in_addr ipaddr[MAXIPADDR];	/* nameserver addresses */
	int naddrs;				/* count of addresses */
} ns_data_t;

ns_data_t nsinfo[MAXNSNAME];	/* nameserver info */
#endif

bool authserver;		/* server is supposed to be authoritative */

/*
 * Host information.
 * Stores names and (single) addresses encountered during the zone listing
 * of all A records that belong to the zone. Non-authoritative glue records
 * that do not belong to the zone are not stored. Glue records that belong
 * to a delegated zone will be filtered out later during the host count scan.
 * The host names are allocated dynamically.
#ifdef notyet
 * The host data should have been allocated dynamically to avoid static
 * limits, but this is less important since it is not saved across calls.
#endif
 */

#define MAXHOSTS 25000		/* maximum count of hostnames per zone */

char *hostname[MAXHOSTS];	/* hostname of host in zone */
ipaddr_t hostaddr[MAXHOSTS];	/* first host address */
bool multaddr[MAXHOSTS];	/* set if this is a multiple address host */
int hostcount = 0;		/* count of hosts in zone */

#ifdef notyet
typedef struct host_data {
	char *hostname;		/* hostname of host in zone */
	ipaddr_t hostaddr;	/* first host address */
	bool multaddr;		/* set if this is a multiple address host */
} host_data_t;

host_data_t hostlist[MAXHOSTS];	/* info on hosts in zone */
#endif

/*
 * Delegated zone information.
 * Stores the names of the delegated zones encountered during the zone
 * listing. The names and the list itself are allocated dynamically.
 */

char **zonename = NULL;		/* names of delegated zones within zone */
int zonecount = 0;		/* count of delegated zones within zone */

/*
 * Address information.
 * Stores the (single) addresses of hosts found in all zones traversed.
 * Used to search for duplicate hosts (same address but different name).
 * The list of addresses is allocated dynamically, and remains allocated.
 * This has now been implemented as a hashed list, using the low-order
 * address bits as the hash key.
 */

#ifdef obsolete
ipaddr_t *addrlist = NULL;	/* global list of addresses */
int addrcount = 0;		/* count of global addresses */
#endif

typedef struct addr_data {
	ipaddr_t *addrlist;	/* global list of addresses */
	int addrcount;		/* count of global addresses */
} addr_data_t;

#define AHASHSIZE	0x2000
#define AHASHMASK	0x1fff

addr_data_t hlist[AHASHSIZE];	/* hash list of global addresses */

/*
 * SOA record information.
 */

typedef struct soa_data {
	char pname[MAXDNAME+1];	/* name of primary server */
	char mname[MAXDNAME+1];	/* name of hostmaster mailbox */
	int serial;		/* serial (version) number */
	int refresh;		/* refresh time in seconds */
	int retry;		/* refresh retry time in seconds */
	int expire;		/* expiration time in seconds */
	int defttl;		/* default time_to_live */
} soa_data_t;

soa_data_t soa;			/* buffer to store soa data */

/*
** LIST_ZONE -- Basic routine to do complete zone listing and checking
** -------------------------------------------------------------------
**
**	Returns:
**		TRUE if the requested info was processed successfully.
**		FALSE otherwise.
*/

int total_calls = 0;		/* number of calls for zone processing */
int total_check = 0;		/* number of zones successfully processe