name.c

bind 9.3结合mysql数据库

					return (DNS_R_LABELTOOLONG);
				count++;
				CONVERTTOASCII(c);
				if (downcase)
					c = maptolower[(int)c];
				*ndata++ = c;
				nrem--;
				nused++;
				state = ft_ordinary;
				break;
			}
			digits = 0;
			value = 0;
			state = ft_escdecimal;
			/* FALLTHROUGH */
		case ft_escdecimal:
			if (!isdigit(c & 0xff))
				return (DNS_R_BADESCAPE);
			value *= 10;
			value += digitvalue[(int)c];
			digits++;
			if (digits == 3) {
				if (value > 255)
					return (DNS_R_BADESCAPE);
				if (count >= 63)
					return (DNS_R_LABELTOOLONG);
				count++;
				if (downcase)
					value = maptolower[value];
				*ndata++ = value;
				nrem--;
				nused++;
				state = ft_ordinary;
			}
			break;
		default:
			FATAL_ERROR(__FILE__, __LINE__,
				    "Unexpected state %d", state);
			/* Does not return. */
		}
	}

	if (!done) {
		if (nrem == 0)
			return (ISC_R_NOSPACE);
		INSIST(tlen == 0);
		if (state != ft_ordinary && state != ft_at)
			return (ISC_R_UNEXPECTEDEND);
		if (state == ft_ordinary) {
			INSIST(count != 0);
			*label = count;
			labels++;
			INSIST(labels <= 127);
			offsets[labels] = nused;
		}
		if (origin != NULL) {
			if (nrem < origin->length)
				return (ISC_R_NOSPACE);
			label = origin->ndata;
			n1 = origin->length;
			nrem -= n1;
			while (n1 > 0) {
				n2 = *label++;
				INSIST(n2 <= 63); /* no bitstring support */
				*ndata++ = n2;
				n1 -= n2 + 1;
				nused += n2 + 1;
				while (n2 > 0) {
					c = *label++;
					if (downcase)
						c = maptolower[(int)c];
					*ndata++ = c;
					n2--;
				}
				labels++;
				if (n1 > 0) {
					INSIST(labels <= 127);
					offsets[labels] = nused;
				}
			}
			if ((origin->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
				name->attributes |= DNS_NAMEATTR_ABSOLUTE;
		}
	} else
		name->attributes |= DNS_NAMEATTR_ABSOLUTE;

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

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

	return (ISC_R_SUCCESS);
}

isc_result_t
dns_name_totext(dns_name_t *name, isc_boolean_t omit_final_dot,
		isc_buffer_t *target)
{
	unsigned char *ndata;
	char *tdata;
	unsigned int nlen, tlen;
	unsigned char c;
	unsigned int trem, count;
	unsigned int labels;
	isc_boolean_t saw_root = ISC_FALSE;

	/*
	 * This function assumes the name is in proper uncompressed
	 * wire format.
	 */
	REQUIRE(VALID_NAME(name));
	REQUIRE(ISC_BUFFER_VALID(target));

	ndata = name->ndata;
	nlen = name->length;
	labels = name->labels;
	tdata = isc_buffer_used(target);
	tlen = isc_buffer_availablelength(target);

	trem = tlen;

	if (labels == 0 && nlen == 0) {
		/*
		 * Special handling for an empty name.
		 */
		if (trem == 0)
			return (ISC_R_NOSPACE);

		/*
		 * The names of these booleans are misleading in this case.
		 * This empty name is not necessarily from the root node of
		 * the DNS root zone, nor is a final dot going to be included.
		 * They need to be set this way, though, to keep the "@"
		 * from being trounced.
		 */
		saw_root = ISC_TRUE;
		omit_final_dot = ISC_FALSE;
		*tdata++ = '@';
		trem--;

		/*
		 * Skip the while() loop.
		 */
		nlen = 0;
	} else if (nlen == 1 && labels == 1 && *ndata == '\0') {
		/*
		 * Special handling for the root label.
		 */
		if (trem == 0)
			return (ISC_R_NOSPACE);

		saw_root = ISC_TRUE;
		omit_final_dot = ISC_FALSE;
		*tdata++ = '.';
		trem--;

		/*
		 * Skip the while() loop.
		 */
		nlen = 0;
	}

	while (labels > 0 && nlen > 0 && trem > 0) {
		labels--;
		count = *ndata++;
		nlen--;
		if (count == 0) {
			saw_root = ISC_TRUE;
			break;
		}
		if (count < 64) {
			INSIST(nlen >= count);
			while (count > 0) {
				c = *ndata;
				switch (c) {
				case 0x22: /* '"' */
				case 0x28: /* '(' */
				case 0x29: /* ')' */
				case 0x2E: /* '.' */
				case 0x3B: /* ';' */
				case 0x5C: /* '\\' */
				/* Special modifiers in zone files. */
				case 0x40: /* '@' */
				case 0x24: /* '$' */
					if (trem < 2)
						return (ISC_R_NOSPACE);
					*tdata++ = '\\';
					CONVERTFROMASCII(c);
					*tdata++ = c;
					ndata++;
					trem -= 2;
					nlen--;
					break;
				default:
					if (c > 0x20 && c < 0x7f) {
						if (trem == 0)
							return (ISC_R_NOSPACE);
						CONVERTFROMASCII(c);
						*tdata++ = c;
						ndata++;
						trem--;
						nlen--;
					} else {
						char buf[5];
						if (trem < 4)
							return (ISC_R_NOSPACE);
						snprintf(buf, sizeof(buf),
							 "\\%03u", c);
						memcpy(tdata, buf, 4);
						tdata += 4;
						trem -= 4;
						ndata++;
						nlen--;
					}
				}
				count--;
			}
		} else {
			FATAL_ERROR(__FILE__, __LINE__,
				    "Unexpected label type %02x", count);
			/* NOTREACHED */
		}

		/*
		 * The following assumes names are absolute.  If not, we
		 * fix things up later.  Note that this means that in some
		 * cases one more byte of text buffer is required than is
		 * needed in the final output.
		 */
		if (trem == 0)
			return (ISC_R_NOSPACE);
		*tdata++ = '.';
		trem--;
	}

	if (nlen != 0 && trem == 0)
		return (ISC_R_NOSPACE);

	if (!saw_root || omit_final_dot)
		trem++;

	isc_buffer_add(target, tlen - trem);

	return (ISC_R_SUCCESS);
}

isc_result_t
dns_name_tofilenametext(dns_name_t *name, isc_boolean_t omit_final_dot,
			isc_buffer_t *target)
{
	unsigned char *ndata;
	char *tdata;
	unsigned int nlen, tlen;
	unsigned char c;
	unsigned int trem, count;
	unsigned int labels;

	/*
	 * This function assumes the name is in proper uncompressed
	 * wire format.
	 */
	REQUIRE(VALID_NAME(name));
	REQUIRE((name->attributes & DNS_NAMEATTR_ABSOLUTE) != 0);
	REQUIRE(ISC_BUFFER_VALID(target));

	ndata = name->ndata;
	nlen = name->length;
	labels = name->labels;
	tdata = isc_buffer_used(target);
	tlen = isc_buffer_availablelength(target);

	trem = tlen;

	if (nlen == 1 && labels == 1 && *ndata == '\0') {
		/*
		 * Special handling for the root label.
		 */
		if (trem == 0)
			return (ISC_R_NOSPACE);

		omit_final_dot = ISC_FALSE;
		*tdata++ = '.';
		trem--;

		/*
		 * Skip the while() loop.
		 */
		nlen = 0;
	}

	while (labels > 0 && nlen > 0 && trem > 0) {
		labels--;
		count = *ndata++;
		nlen--;
		if (count == 0)
			break;
		if (count < 64) {
			INSIST(nlen >= count);
			while (count > 0) {
				c = *ndata;
				if ((c >= 0x30 && c <= 0x39) || /* digit */
				    (c >= 0x41 && c <= 0x5A) ||	/* uppercase */
				    (c >= 0x61 && c <= 0x7A) || /* lowercase */
				    c == 0x2D ||		/* hyphen */
				    c == 0x5F)			/* underscore */
				{
					if (trem == 0)
						return (ISC_R_NOSPACE);
					/* downcase */
					if (c >= 0x41 && c <= 0x5A)
						c += 0x20;
					CONVERTFROMASCII(c);
					*tdata++ = c;
					ndata++;
					trem--;
					nlen--;
				} else {
					if (trem < 3)
						return (ISC_R_NOSPACE);
					sprintf(tdata, "%%%02X", c);
					tdata += 3;
					trem -= 3;
					ndata++;
					nlen--;
				}
				count--;
			}
		} else {
			FATAL_ERROR(__FILE__, __LINE__,
				    "Unexpected label type %02x", count);
			/* NOTREACHED */
		}

		/*
		 * The following assumes names are absolute.  If not, we
		 * fix things up later.  Note that this means that in some
		 * cases one more byte of text buffer is required than is
		 * needed in the final output.
		 */
		if (trem == 0)
			return (ISC_R_NOSPACE);
		*tdata++ = '.';
		trem--;
	}

	if (nlen != 0 && trem == 0)
		return (ISC_R_NOSPACE);

	if (omit_final_dot)
		trem++;

	isc_buffer_add(target, tlen - trem);

	return (ISC_R_SUCCESS);
}

isc_result_t
dns_name_downcase(dns_name_t *source, dns_name_t *name, isc_buffer_t *target) {
	unsigned char *sndata, *ndata;
	unsigned int nlen, count, labels;
	isc_buffer_t buffer;

	/*
	 * Downcase 'source'.
	 */

	REQUIRE(VALID_NAME(source));
	REQUIRE(VALID_NAME(name));
	if (source == name) {
		REQUIRE((name->attributes & DNS_NAMEATTR_READONLY) == 0);
		isc_buffer_init(&buffer, source->ndata, source->length);
		target = &buffer;
		ndata = source->ndata;
	} else {
		REQUIRE(BINDABLE(name));
		REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
			(target == NULL && ISC_BUFFER_VALID(name->buffer)));
		if (target == NULL) {
			target = name->buffer;
			isc_buffer_clear(name->buffer);
		}
		ndata = (unsigned char *)target->base + target->used;
		name->ndata = ndata;
	}

	sndata = source->ndata;
	nlen = source->length;
	labels = source->labels;

	if (nlen > (target->length - target->used)) {
		MAKE_EMPTY(name);
		return (ISC_R_NOSPACE);
	}

	while (labels > 0 && nlen > 0) {
		labels--;
		count = *sndata++;
		*ndata++ = count;
		nlen--;
		if (count < 64) {
			INSIST(nlen >= count);
			while (count > 0) {
				*ndata++ = maptolower[(*sndata++)];
				nlen--;
				count--;
			}
		} else {
			FATAL_ERROR(__FILE__, __LINE__,
				    "Unexpected label type %02x", count);
			/* Does not return. */
		}
	}

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

	isc_buffer_add(target, name->length);

	return (ISC_R_SUCCESS);
}

static void
set_offsets(const dns_name_t *name, unsigned char *offsets,
	    dns_name_t *set_name)
{
	unsigned int offset, count, length, nlabels;
	unsigned char *ndata;
	isc_boolean_t absolute;

	ndata = name->ndata;
	length = name->length;
	offset = 0;
	nlabels = 0;
	absolute = ISC_FALSE;
	while (offset != length) {
		INSIST(nlabels < 128);
		offsets[nlabels++] = offset;
		count = *ndata++;
		offset++;
		INSIST(count <= 63);
		offset += count;
		ndata += count;
		INSIST(offset <= length);
		if (count == 0) {
			absolute = ISC_TRUE;
			break;
		}
	}
	if (set_name != NULL) {
		INSIST(set_name == name);

		set_name->labels = nlabels;
		set_name->length = offset;
		if (absolute)
			set_name->attributes |= DNS_NAMEATTR_ABSOLUTE;
		else
			set_name->attributes &= ~DNS_NAMEATTR_ABSOLUTE;
	}
	INSIST(nlabels == name->labels);
	INSIST(offset == name->length);
}

isc_result_t
dns_name_fromwire(dns_name_t *name, isc_buffer_t *source,
		  dns_decompress_t *dctx, unsigned int options,
		  isc_buffer_t *target)
{
	unsigned char *cdata, *ndata;
	unsigned int cused; /* Bytes of compressed name data used */
	unsigned int hops,  nused, labels, n, nmax;
	unsigned int current, new_current, biggest_pointer;
	isc_boolean_t done;
	fw_state state = fw_start;
	unsigned int c;
	unsigned char *offsets;
	dns_offsets_t odata;
	isc_boolean_t downcase;

	/*
	 * Copy the possibly-compressed name at source into target,
	 * decompressing it.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
		(target == NULL && ISC_BUFFER_VALID(name->buffer)));

	downcase = ISC_TF((options & DNS_NAME_DOWNCASE) != 0);

	if (target == NULL && name->buffer != NULL) {
		target = name->buffer;
		isc_buffer_clear(target);
	}

	REQUIRE(dctx != NULL);
	REQUIRE(BINDABLE(name));

	INIT_OFFSETS(name, offsets, odata);

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

	/*
	 * Initialize things to make the compiler happy; they're not required.
	 */
	n = 0;
	new_current = 0;

	/*
	 * Set up.
	 */
	labels = 0;
	hops = 0;
	done = ISC_FALSE;

	ndata = isc_buffer_used(target);
	nused = 0;

	/*
	 * Find the maximum number of uncompressed target name
	 * bytes we are willing to generate.  This is the smaller
	 * of the available target buffer length and the
	 * maximum legal domain name length (255).
	 */
	nmax = isc_buffer_availablelength(target);
	if (nmax > DNS_NAME_MAXWIRE)
		nmax = DNS_NAME_MAXWIRE;

	cdata = isc_buffer_current(source);
	cused = 0;

	current = source->current;
	biggest_pointer = current;

	/*
	 * Note:  The following code is not optimized for speed, but
	 * rather for correctness.  Speed will be addressed in the future.
	 */