res_debug.c

一个C源代码分析器

	if ((n = dn_expand(msg, msg + len, cp, name, sizeof name)) < 0)
		return (NULL);
	if (name[0] == '\0')
		putc('.', file);
	else
		fputs(name, file);
	return (cp + n);
}

const u_char *
__p_cdname(cp, msg, file)
	const u_char *cp, *msg;
	FILE *file;
{
	return (p_cdnname(cp, msg, PACKETSZ, file));
}

/* XXX:	the rest of these functions need to become length-limited, too. (vix)
 */

const u_char *
__p_fqname(cp, msg, file)
	const u_char *cp, *msg;
	FILE *file;
{
	char name[MAXDNAME];
	int n, len;

	if ((n = dn_expand(msg, cp + MAXCDNAME, cp, name, sizeof name)) < 0)
		return (NULL);
	if (name[0] == '\0') {
		putc('.', file);
	} else {
		fputs(name, file);
		if (name[strlen(name) - 1] != '.')
			putc('.', file);
	}
	return (cp + n);
}

/*
 * Print resource record fields in human readable form.
 */
const u_char *
__p_rr(cp, msg, file)
	const u_char *cp, *msg;
	FILE *file;
{
	int type, class, dlen, n, c;
	struct in_addr inaddr;
	const u_char *cp1, *cp2;
	u_int32_t tmpttl, t;
	int lcnt;

	if ((cp = p_fqname(cp, msg, file)) == NULL)
		return (NULL);			/* compression error */
	type = _getshort((u_char*)cp);
	cp += INT16SZ;
	class = _getshort((u_char*)cp);
	cp += INT16SZ;
	tmpttl = _getlong((u_char*)cp);
	cp += INT32SZ;
	dlen = _getshort((u_char*)cp);
	cp += INT16SZ;
	cp1 = cp;
	if ((!_res.pfcode) || (_res.pfcode & RES_PRF_TTLID))
		fprintf(file, "\t%lu", tmpttl);
	if ((!_res.pfcode) || (_res.pfcode & RES_PRF_CLASS))
		fprintf(file, "\t%s", __p_class(class));
	fprintf(file, "\t%s", __p_type(type));
	/*
	 * Print type specific data, if appropriate
	 */
	switch (type) {
	case T_A:
		switch (class) {
		case C_IN:
		case C_HS:
			bcopy(cp, (char *)&inaddr, INADDRSZ);
			if (dlen == 4) {
				fprintf(file,"\t%s", inet_ntoa(inaddr));
				cp += dlen;
			} else if (dlen == 7) {
				char *address;
				u_char protocol;
				u_short port;

				address = inet_ntoa(inaddr);
				cp += INADDRSZ;
				protocol = *(u_char*)cp;
				cp += sizeof(u_char);
				port = _getshort((u_char*)cp);
				cp += INT16SZ;
				fprintf(file, "\t%s\t; proto %d, port %d",
					address, protocol, port);
			}
			break;
		default:
			cp += dlen;
		}
		break;
	case T_CNAME:
	case T_MB:
	case T_MG:
	case T_MR:
	case T_NS:
	case T_PTR:
		putc('\t', file);
		cp = p_fqname(cp, msg, file);
		break;

	case T_HINFO:
	case T_ISDN:
		if (n = *cp++) {
			fprintf(file,"\t%.*s", n, cp);
			cp += n;
		}
		if (n = *cp++) {
			fprintf(file,"\t%.*s", n, cp);
			cp += n;
		}
		break;

	case T_SOA:
		putc('\t', file);
		cp = p_fqname(cp, msg, file);	/* origin */
		putc(' ', file);
		cp = p_fqname(cp, msg, file);	/* mail addr */
		fputs(" (\n", file);
		t = _getlong((u_char*)cp);  cp += INT32SZ;
		fprintf(file,"\t\t\t%lu\t; serial\n", t);
		t = _getlong((u_char*)cp);  cp += INT32SZ;
		fprintf(file,"\t\t\t%lu\t; refresh (%s)\n", t, __p_time(t));
		t = _getlong((u_char*)cp);  cp += INT32SZ;
		fprintf(file,"\t\t\t%lu\t; retry (%s)\n", t, __p_time(t));
		t = _getlong((u_char*)cp);  cp += INT32SZ;
		fprintf(file,"\t\t\t%lu\t; expire (%s)\n", t, __p_time(t));
		t = _getlong((u_char*)cp);  cp += INT32SZ;
		fprintf(file,"\t\t\t%lu )\t; minimum (%s)", t, __p_time(t));
		break;

	case T_MX:
	case T_AFSDB:
	case T_RT:
		fprintf(file,"\t%d ", _getshort((u_char*)cp));
		cp += INT16SZ;
		cp = p_fqname(cp, msg, file);
		break;

  	case T_TXT:
	case T_X25:
		(void) fputs("\t\"", file);
		cp2 = cp1 + dlen;
		while (cp < cp2) {
			if (n = (unsigned char) *cp++) {
				for (c = n; c > 0 && cp < cp2; c--)
					if (*cp == '\n') {
					    (void) putc('\\', file);
					    (void) putc(*cp++, file);
					} else
					    (void) putc(*cp++, file);
			}
		}
		putc('"', file);
  		break;

  	case T_NSAP:
		(void) fprintf(file, "\t%s", inet_nsap_ntoa(dlen, cp, NULL));
		cp += dlen;
  		break;

	case T_MINFO:
	case T_RP:
		putc('\t', file);
		cp = p_fqname(cp, msg, file);
		putc(' ', file);
		cp = p_fqname(cp, msg, file);
		break;

	case T_UINFO:
		putc('\t', file);
		fputs((char *)cp, file);
		cp += dlen;
		break;

	case T_UID:
	case T_GID:
		if (dlen == 4) {
			fprintf(file,"\t%u", _getlong((u_char*)cp));
			cp += INT32SZ;
		}
		break;

	case T_WKS:
		if (dlen < INT32SZ + 1)
			break;
		bcopy(cp, (char *)&inaddr, INADDRSZ);
		cp += INT32SZ;
		fprintf(file, "\t%s %s ( ",
			inet_ntoa(inaddr),
			deproto((int) *cp));
		cp += sizeof(u_char);
		n = 0;
		lcnt = 0;
		while (cp < cp1 + dlen) {
			c = *cp++;
			do {
 				if (c & 0200) {
					if (lcnt == 0) {
						fputs("\n\t\t\t", file);
						lcnt = 5;
					}
					fputs(dewks(n), file);
					putc(' ', file);
					lcnt--;
				}
 				c <<= 1;
			} while (++n & 07);
		}
		putc(')', file);
		break;

#ifdef ALLOW_T_UNSPEC
	case T_UNSPEC:
		{
			int NumBytes = 8;
			u_char *DataPtr;
			int i;

			if (dlen < NumBytes) NumBytes = dlen;
			fprintf(file, "\tFirst %d bytes of hex data:",
				NumBytes);
			for (i = 0, DataPtr = cp; i < NumBytes; i++, DataPtr++)
				fprintf(file, " %x", *DataPtr);
			cp += dlen;
		}
		break;
#endif /* ALLOW_T_UNSPEC */

	default:
		fprintf(file,"\t?%d?", type);
		cp += dlen;
	}
#if 0
	fprintf(file, "\t; dlen=%d, ttl %s\n", dlen, __p_time(tmpttl));
#else
	putc('\n', file);
#endif
	if (cp - cp1 != dlen) {
		fprintf(file,";; packet size error (found %d, dlen was %d)\n",
			cp - cp1, dlen);
		cp = NULL;
	}
	return (cp);
}

static	char nbuf[40];

/*
 * Return a string for the type
 */
const char *
__p_type(type)
	int type;
{
	switch (type) {
	case T_A:	return "A";
	case T_NS:	return "NS";
	case T_CNAME:	return "CNAME";
	case T_SOA:	return "SOA";
	case T_MB:	return "MB";
	case T_MG:	return "MG";
	case T_MR:	return "MR";
	case T_NULL:	return "NULL";
	case T_WKS:	return "WKS";
	case T_PTR:	return "PTR";
	case T_HINFO:	return "HINFO";
	case T_MINFO:	return "MINFO";
	case T_MX:	return "MX";
	case T_TXT:	return "TXT";
	case T_NSAP:	return "NSAP";
	case T_RP:	return "RP";
	case T_AFSDB:	return "AFSDB";
	case T_X25:	return "X25";
	case T_ISDN:	return "ISDN";
	case T_RT:	return "RT";
	case T_AXFR:	return "AXFR";
	case T_MAILB:	return "MAILB";
	case T_MAILA:	return "MAILA";
	case T_ANY:	return "ANY";
	case T_UINFO:	return "UINFO";
	case T_UID:	return "UID";
	case T_GID:	return "GID";
#ifdef ALLOW_T_UNSPEC
	case T_UNSPEC:	return "UNSPEC";
#endif /* ALLOW_T_UNSPEC */
	default:	(void)sprintf(nbuf, "%d", type); return (nbuf);
	}
}

/*
 * Return a mnemonic for class
 */
const char *
__p_class(class)
	int class;
{
	switch (class) {
	case C_IN:	return("IN");
	case C_HS:	return("HS");
	case C_ANY:	return("ANY");
	default:	(void)sprintf(nbuf, "%d", class); return (nbuf);
	}
}

/*
 * Return a mnemonic for an option
 */
const char *
__p_option(option)
	u_long option;
{
	switch (option) {
	case RES_INIT:		return "init";
	case RES_DEBUG:		return "debug";
	case RES_AAONLY:	return "aaonly";
	case RES_USEVC:		return "usevc";
	case RES_PRIMARY:	return "primry";
	case RES_IGNTC:		return "igntc";
	case RES_RECURSE:	return "recurs";
	case RES_DEFNAMES:	return "defnam";
	case RES_STAYOPEN:	return "styopn";
	case RES_DNSRCH:	return "dnsrch";
	case RES_INSECURE1:	return "insecure1";
	case RES_INSECURE2:	return "insecure2";
	default:		sprintf(nbuf, "?0x%x?", option); return nbuf;
	}
}

/*
 * Return a mnemonic for a time to live
 */
char *
__p_time(value)
	u_int32_t value;
{
	int secs, mins, hours, days;
	register char *p;

	if (value == 0) {
		strcpy(nbuf, "0 secs");
		return (nbuf);
	}

	secs = value % 60;
	value /= 60;
	mins = value % 60;
	value /= 60;
	hours = value % 24;
	value /= 24;
	days = value;
	value = 0;

#define	PLURALIZE(x)	x, (x == 1) ? "" : "s"
	p = nbuf;
	if (days) {
		(void)sprintf(p, "%d day%s", PLURALIZE(days));
		while (*++p);
	}
	if (hours) {
		if (days)
			*p++ = ' ';
		(void)sprintf(p, "%d hour%s", PLURALIZE(hours));
		while (*++p);
	}
	if (mins) {
		if (days || hours)
			*p++ = ' ';
		(void)sprintf(p, "%d min%s", PLURALIZE(mins));
		while (*++p);
	}
	if (secs || ! (days || hours || mins)) {
		if (days || hours || mins)
			*p++ = ' ';
		(void)sprintf(p, "%d sec%s", PLURALIZE(secs));
	}
	return (nbuf);
}