name.c

bind 9.3结合mysql数据库

	while (current < source->active && !done) {
		c = *cdata++;
		current++;
		if (hops == 0)
			cused++;

		switch (state) {
		case fw_start:
			if (c < 64) {
				offsets[labels] = nused;
				labels++;
				if (nused + c + 1 > nmax)
					goto full;
				nused += c + 1;
				*ndata++ = c;
				if (c == 0)
					done = ISC_TRUE;
				n = c;
				state = fw_ordinary;
			} else if (c >= 128 && c < 192) {
				/*
				 * 14 bit local compression pointer.
				 * Local compression is no longer an
				 * IETF draft.
				 */
				return (DNS_R_BADLABELTYPE);
			} else if (c >= 192) {
				/*
				 * Ordinary 14-bit pointer.
				 */
				if ((dctx->allowed & DNS_COMPRESS_GLOBAL14) ==
				    0)
					return (DNS_R_DISALLOWED);
				new_current = c & 0x3F;
				n = 1;
				state = fw_newcurrent;
			} else
				return (DNS_R_BADLABELTYPE);
			break;
		case fw_ordinary:
			if (downcase)
				c = maptolower[c];
			/* FALLTHROUGH */
		case fw_copy:
			*ndata++ = c;
			n--;
			if (n == 0)
				state = fw_start;
			break;
		case fw_newcurrent:
			new_current *= 256;
			new_current += c;
			n--;
			if (n != 0)
				break;
			if (new_current >= biggest_pointer)
				return (DNS_R_BADPOINTER);
			biggest_pointer = new_current;
			current = new_current;
			cdata = (unsigned char *)source->base +
				current;
			hops++;
			if (hops > DNS_POINTER_MAXHOPS)
				return (DNS_R_TOOMANYHOPS);
			state = fw_start;
			break;
		default:
			FATAL_ERROR(__FILE__, __LINE__,
				    "Unknown state %d", state);
			/* Does not return. */
		}
	}

	if (!done)
		return (ISC_R_UNEXPECTEDEND);

	name->ndata = (unsigned char *)target->base + target->used;
	name->labels = labels;
	name->length = nused;
	name->attributes |= DNS_NAMEATTR_ABSOLUTE;

	isc_buffer_forward(source, cused);
	isc_buffer_add(target, name->length);

	return (ISC_R_SUCCESS);

 full:
	if (nmax == DNS_NAME_MAXWIRE)
		/*
		 * The name did not fit even though we had a buffer
		 * big enough to fit a maximum-length name.
		 */
		return (DNS_R_NAMETOOLONG);
	else
		/*
		 * The name might fit if only the caller could give us a
		 * big enough buffer.
		 */
		return (ISC_R_NOSPACE);

}

isc_result_t
dns_name_towire(dns_name_t *name, dns_compress_t *cctx, isc_buffer_t *target) {
	unsigned int methods;
	isc_uint16_t offset;
	dns_name_t gp;	/* Global compression prefix */
	isc_boolean_t gf;	/* Global compression target found */
	isc_uint16_t go;	/* Global compression offset */
	dns_offsets_t clo;
	dns_name_t clname;

	/*
	 * Convert 'name' into wire format, compressing it as specified by the
	 * compression context 'cctx', and storing the result in 'target'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE(cctx != NULL);
	REQUIRE(ISC_BUFFER_VALID(target));

	/*
	 * If 'name' doesn't have an offsets table, make a clone which
	 * has one.
	 */
	if (name->offsets == NULL) {
		DNS_NAME_INIT(&clname, clo);
		dns_name_clone(name, &clname);
		name = &clname;
	}
	DNS_NAME_INIT(&gp, NULL);

	offset = target->used;	/*XXX*/

	methods = dns_compress_getmethods(cctx);

	if ((methods & DNS_COMPRESS_GLOBAL14) != 0)
		gf = dns_compress_findglobal(cctx, name, &gp, &go);
	else
		gf = ISC_FALSE;

	/*
	 * If the offset is too high for 14 bit global compression, we're
	 * out of luck.
	 */
	if (gf && go >= 0x4000)
		gf = ISC_FALSE;

	/*
	 * Will the compression pointer reduce the message size?
	 */
	if (gf && (gp.length + 2) >= name->length)
		gf = ISC_FALSE;

	if (gf) {
		if (target->length - target->used < gp.length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     gp.ndata, (size_t)gp.length);
		isc_buffer_add(target, gp.length);
		go |= 0xc000;
		if (target->length - target->used < 2)
			return (ISC_R_NOSPACE);
		isc_buffer_putuint16(target, go);
		if (gp.length != 0)
			dns_compress_add(cctx, name, &gp, offset);
	} else {
		if (target->length - target->used < name->length)
			return (ISC_R_NOSPACE);
		(void)memcpy((unsigned char *)target->base + target->used,
			     name->ndata, (size_t)name->length);
		isc_buffer_add(target, name->length);
		dns_compress_add(cctx, name, name, offset);
	}
	return (ISC_R_SUCCESS);
}

isc_result_t
dns_name_concatenate(dns_name_t *prefix, dns_name_t *suffix, dns_name_t *name,
		     isc_buffer_t *target)
{
	unsigned char *ndata, *offsets;
	unsigned int nrem, labels, prefix_length, length;
	isc_boolean_t copy_prefix = ISC_TRUE;
	isc_boolean_t copy_suffix = ISC_TRUE;
	isc_boolean_t absolute = ISC_FALSE;
	dns_name_t tmp_name;
	dns_offsets_t odata;

	/*
	 * Concatenate 'prefix' and 'suffix'.
	 */

	REQUIRE(prefix == NULL || VALID_NAME(prefix));
	REQUIRE(suffix == NULL || VALID_NAME(suffix));
	REQUIRE(name == NULL || VALID_NAME(name));
	REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
		(target == NULL && name != NULL && ISC_BUFFER_VALID(name->buffer)));
	if (prefix == NULL || prefix->labels == 0)
		copy_prefix = ISC_FALSE;
	if (suffix == NULL || suffix->labels == 0)
		copy_suffix = ISC_FALSE;
	if (copy_prefix &&
	    (prefix->attributes & DNS_NAMEATTR_ABSOLUTE) != 0) {
		absolute = ISC_TRUE;
		REQUIRE(!copy_suffix);
	}
	if (name == NULL) {
		DNS_NAME_INIT(&tmp_name, odata);
		name = &tmp_name;
	}
	if (target == NULL) {
		INSIST(name->buffer != NULL);
		target = name->buffer;
		isc_buffer_clear(name->buffer);
	}

	REQUIRE(BINDABLE(name));

	/*
	 * Set up.
	 */
	nrem = target->length - target->used;
	ndata = (unsigned char *)target->base + target->used;
	if (nrem > DNS_NAME_MAXWIRE)
		nrem = DNS_NAME_MAXWIRE;
	length = 0;
	prefix_length = 0;
	labels = 0;
	if (copy_prefix) {
		prefix_length = prefix->length;
		length += prefix_length;
		labels += prefix->labels;
	}
	if (copy_suffix) {
		length += suffix->length;
		labels += suffix->labels;
	}
	if (length > DNS_NAME_MAXWIRE) {
		MAKE_EMPTY(name);
		return (DNS_R_NAMETOOLONG);
	}
	if (length > nrem) {
		MAKE_EMPTY(name);
		return (ISC_R_NOSPACE);
	}

	if (copy_suffix) {
		if ((suffix->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
			absolute = ISC_TRUE;
		if (suffix == name && suffix->buffer == target)
			memmove(ndata + prefix_length, suffix->ndata,
				suffix->length);
		else
			memcpy(ndata + prefix_length, suffix->ndata,
			       suffix->length);
	}

	/*
	 * If 'prefix' and 'name' are the same object, and the object has
	 * a dedicated buffer, and we're using it, then we don't have to
	 * copy anything.
	 */
	if (copy_prefix && (prefix != name || prefix->buffer != target))
		memcpy(ndata, prefix->ndata, prefix_length);

	name->ndata = ndata;
	name->labels = labels;
	name->length = length;
	if (absolute)
		name->attributes = DNS_NAMEATTR_ABSOLUTE;
	else
		name->attributes = 0;

	if (name->labels > 0 && name->offsets != NULL) {
		INIT_OFFSETS(name, offsets, odata);
		set_offsets(name, offsets, NULL);
	}

	isc_buffer_add(target, name->length);

	return (ISC_R_SUCCESS);
}

void
dns_name_split(dns_name_t *name, unsigned int suffixlabels,
	       dns_name_t *prefix, dns_name_t *suffix)

{
	unsigned int splitlabel;

	REQUIRE(VALID_NAME(name));
	REQUIRE(suffixlabels > 0);
	REQUIRE(suffixlabels < name->labels);
	REQUIRE(prefix != NULL || suffix != NULL);
	REQUIRE(prefix == NULL ||
		(VALID_NAME(prefix) &&
		 prefix->buffer != NULL &&
		 BINDABLE(prefix)));
	REQUIRE(suffix == NULL ||
		(VALID_NAME(suffix) &&
		 suffix->buffer != NULL &&
		 BINDABLE(suffix)));

	splitlabel = name->labels - suffixlabels;

	if (prefix != NULL)
		dns_name_getlabelsequence(name, 0, splitlabel, prefix);

	if (suffix != NULL)
		dns_name_getlabelsequence(name, splitlabel,
					  suffixlabels, suffix);

	return;
}

isc_result_t
dns_name_dup(dns_name_t *source, isc_mem_t *mctx, dns_name_t *target) {
	/*
	 * Make 'target' a dynamically allocated copy of 'source'.
	 */

	REQUIRE(VALID_NAME(source));
	REQUIRE(source->length > 0);
	REQUIRE(VALID_NAME(target));
	REQUIRE(BINDABLE(target));

	/*
	 * Make 'target' empty in case of failure.
	 */
	MAKE_EMPTY(target);

	target->ndata = isc_mem_get(mctx, source->length);
	if (target->ndata == NULL)
		return (ISC_R_NOMEMORY);

	memcpy(target->ndata, source->ndata, source->length);

	target->length = source->length;
	target->labels = source->labels;
	target->attributes = DNS_NAMEATTR_DYNAMIC;
	if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
		target->attributes |= DNS_NAMEATTR_ABSOLUTE;
	if (target->offsets != NULL) {
		if (source->offsets != NULL)
			memcpy(target->offsets, source->offsets,
			       source->labels);
		else
			set_offsets(target, target->offsets, NULL);
	}

	return (ISC_R_SUCCESS);
}

isc_result_t
dns_name_dupwithoffsets(dns_name_t *source, isc_mem_t *mctx,
			dns_name_t *target)
{
	/*
	 * Make 'target' a read-only dynamically allocated copy of 'source'.
	 * 'target' will also have a dynamically allocated offsets table.
	 */

	REQUIRE(VALID_NAME(source));
	REQUIRE(source->length > 0);
	REQUIRE(VALID_NAME(target));
	REQUIRE(BINDABLE(target));
	REQUIRE(target->offsets == NULL);

	/*
	 * Make 'target' empty in case of failure.
	 */
	MAKE_EMPTY(target);

	target->ndata = isc_mem_get(mctx, source->length + source->labels);
	if (target->ndata == NULL)
		return (ISC_R_NOMEMORY);

	memcpy(target->ndata, source->ndata, source->length);

	target->length = source->length;
	target->labels = source->labels;
	target->attributes = DNS_NAMEATTR_DYNAMIC | DNS_NAMEATTR_DYNOFFSETS |
		DNS_NAMEATTR_READONLY;
	if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
		target->attributes |= DNS_NAMEATTR_ABSOLUTE;
	target->offsets = target->ndata + source->length;
	if (source->offsets != NULL)
		memcpy(target->offsets, source->offsets, source->labels);
	else
		set_offsets(target, target->offsets, NULL);

	return (ISC_R_SUCCESS);
}

void
dns_name_free(dns_name_t *name, isc_mem_t *mctx) {
	size_t size;

	/*
	 * Free 'name'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE((name->attributes & DNS_NAMEATTR_DYNAMIC) != 0);

	size = name->length;
	if ((name->attributes & DNS_NAMEATTR_DYNOFFSETS) != 0)
		size += name->labels;
	isc_mem_put(mctx, name->ndata, size);
	dns_name_invalidate(name);
}

isc_result_t
dns_name_digest(dns_name_t *name, dns_digestfunc_t digest, void *arg) {
	dns_name_t downname;
	unsigned char data[256];
	isc_buffer_t buffer;
	isc_result_t result;
	isc_region_t r;

	/*
	 * Send 'name' in DNSSEC canonical form to 'digest'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE(digest != NULL);

	DNS_NAME_INIT(&downname, NULL);
	isc_buffer_init(&buffer, data, sizeof(data));

	result = dns_name_downcase(name, &downname, &buffer);
	if (result != ISC_R_SUCCESS)
		return (result);

	isc_buffer_usedregion(&buffer, &r);

	return ((digest)(arg, &r));
}

isc_boolean_t
dns_name_dynamic(dns_name_t *name) {
	REQUIRE(VALID_NAME(name));

	/*
	 * Returns whether there is dynamic memory associated with this name.
	 */

	return ((name->attributes & DNS_NAMEATTR_DYNAMIC) != 0 ?
		ISC_TRUE : ISC_FALSE);
}

isc_result_t
dns_name_print(dns_name_t *name, FILE *stream) {
	isc_result_t result;
	isc_buffer_t b;
	isc_region_t r;
	char t[1024];

	/*
	 * Print 'name' on 'stream'.
	 */

	REQUIRE(VALID_NAME(name));

	isc_buffer_init(&b, t, sizeof(t));
	result = dns_name_totext(name, ISC_FALSE, &b);
	if (result != ISC_R_SUCCESS)
		return (result);
	isc_buffer_usedregion(&b, &r);
	fprintf(stream, "%.*s", (int)r.length, (char *)r.base);

	return (ISC_R_SUCCESS);
}

void
dns_name_format(dns_name_t *name, char *cp, unsigned int size) {
	isc_result_t result;
	isc_buffer_t buf;

	REQUIRE(size > 0);

	/*
	 * Leave room for null termination after buffer.
	 */
	isc_buffer_init(&buf, cp, size - 1);
	result = dns_name_totext(name, ISC_TRUE, &buf);
	if (result == ISC_R_SUCCESS) {
		/*
		 * Null terminate.
		 */
		isc_region_t r;
		isc_buffer_usedregion(&buf, &r);
		((char *) r.base)[r.length] = '\0';

	} else
		snprintf(cp, size, "<unknown>");
}

isc_result_t
dns_name_copy(dns_name_t *source, dns_name_t *dest, isc_buffer_t *target) {
	unsigned char *ndata;

	/*
	 * Make dest a copy of source.
	 */

	REQUIRE(VALID_NAME(source));
	REQUIRE(VALID_NAME(dest));
	REQUIRE(target != NULL || dest->buffer != NULL);

	if (target == NULL) {
		target = dest->buffer;
		isc_buffer_clear(dest->buffer);
	}

	REQUIRE(BINDABLE(dest));

	/*
	 * Set up.
	 */
	if (target->length - target->used < source->length)
		return (ISC_R_NOSPACE);

	ndata = (unsigned char *)target->base + target->used;
	dest->ndata = target->base;

	memcpy(ndata, source->ndata, source->length);

	dest->ndata = ndata;
	dest->labels = source->labels;
	dest->length = source->length;
	if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
		dest->attributes = DNS_NAMEATTR_ABSOLUTE;
	else
		dest->attributes = 0;

	if (dest->labels > 0 && dest->offsets != NULL) {
		if (source->offsets != NULL)
			memcpy(dest->offsets, source->offsets, source->labels);
		else
			set_offsets(dest, dest->offsets, NULL);
	}

	isc_buffer_add(target, dest->length);

	return (ISC_R_SUCCESS);
}