From fb5099c5dc6b8e7b632c2ac64cc01abc80838859 Mon Sep 17 00:00:00 2001
From: Lubos Slovak <lubos.slovak@nic.cz>
Date: Thu, 18 Nov 2010 13:31:32 +0100
Subject: [PATCH] RDATA modifications.
The previous approach made converting RDATA to wire format too
complex. Now RDATA items distinguish only between domain name
and other data. The format is given by a descriptor.
TODO: Consider saving the length of the data to the byte array
always, so getting it would not require that huge switch.
refs #119
---
src/dnslib/rdata.c | 148 ++++++++++++++++-----------------------------
src/dnslib/rdata.h | 14 ++---
2 files changed, 59 insertions(+), 103 deletions(-)
diff --git a/src/dnslib/rdata.c b/src/dnslib/rdata.c
index 51ac0b1cd..948c4cf90 100644
--- a/src/dnslib/rdata.c
+++ b/src/dnslib/rdata.c
@@ -142,34 +142,8 @@ uint dnslib_rdata_wire_size( const dnslib_rdata_t *rdata,
case DNSLIB_RDATA_WF_LITERAL_DNAME:
size += dnslib_dname_size(rdata->items[i].dname);
break;
- case DNSLIB_RDATA_WF_BYTE:
- size += 1;
- break;
- case DNSLIB_RDATA_WF_SHORT:
- size += 2;
- break;
- case DNSLIB_RDATA_WF_LONG:
- size += 4;
- break;
- case DNSLIB_RDATA_WF_A:
- size += 4;
- break;
- case DNSLIB_RDATA_WF_AAAA:
- size += 16;
- break;
- case DNSLIB_RDATA_WF_TEXT:
- case DNSLIB_RDATA_WF_BINARYWITHLENGTH:
- // size stored in the first byte, but the first byte also counts
- size += rdata->items[i].raw_data[0] + 1;
- break;
- case DNSLIB_RDATA_WF_BINARY:
- case DNSLIB_RDATA_WF_APL: // saved as binary
- case DNSLIB_RDATA_WF_IPSECGATEWAY: // saved as binary
- // size stored in the first byte, first byte doesn't count
- size += rdata->items[i].raw_data[0];
- break;
default:
- assert(0);
+ size += rdata->items[i].raw_data[0];
}
}
return size;
@@ -187,74 +161,55 @@ int dnslib_rdata_to_wire( const dnslib_rdata_t *rdata, const uint8_t *format,
for (int i = 0; i < rdata->count; ++i) {
assert(copied < MAX_RDATA_WIRE_SIZE);
+ const uint8_t *from = rdata->items[i].raw_data;
+ uint size = 0;
+
switch (format[i]) {
case DNSLIB_RDATA_WF_COMPRESSED_DNAME:
case DNSLIB_RDATA_WF_UNCOMPRESSED_DNAME:
- case DNSLIB_RDATA_WF_LITERAL_DNAME: {
- uint size = dnslib_dname_size(rdata->items[i].dname);
- memcpy(to, dnslib_dname_name(rdata->items[i].dname), size);
- to += size;
- copied += size;
- } break;
+ case DNSLIB_RDATA_WF_LITERAL_DNAME:
+ size = dnslib_dname_size(rdata->items[i].dname);
+ from = dnslib_dname_name(rdata->items[i].dname);
+
+ break;
case DNSLIB_RDATA_WF_BYTE:
- *(to++) = rdata->items[i].int8;
- ++copied;
+ size = 1;
+ break;
+ case DNSLIB_RDATA_WF_SHORT:
+ size = 2;
+ break;
+ case DNSLIB_RDATA_WF_LONG:
+ size = 4;
+ break;
+ case DNSLIB_RDATA_WF_A:
+ size = 4;
+ break;
+ case DNSLIB_RDATA_WF_AAAA:
+ size = 16;
break;
- case DNSLIB_RDATA_WF_SHORT: {
- const uint8_t *from = (uint8_t *)(&rdata->items[i].int16);
- // copy from last byte to first (little to big endian)
- // TODO: check endianness of the machine
- from += 1;
- for (int i = 0; i < 2; ++i) {
- *(to++) = *(from--);
- ++copied;
- }
- } break;
- case DNSLIB_RDATA_WF_LONG: {
- const uint8_t *from = (uint8_t *)(&rdata->items[i].int32);
- // copy from last byte to first (little to big endian)
- // TODO: check endianness of the machine
- from += 3;
- for (int i = 0; i < 4; ++i) {
- *(to++) = *(from--);
- ++copied;
- }
- } break;
- case DNSLIB_RDATA_WF_A: {
- const uint8_t *from = rdata->items[i].a;
- for (int i = 0; i < 4; ++i) {
- *(to++) = *(from++);
- ++copied;
- }
- } break;
- case DNSLIB_RDATA_WF_AAAA: {
- const uint8_t *from = rdata->items[i].raw_data;
- for (int i = 0; i < 16; ++i) {
- *(to++) = *(from++);
- ++copied;
- }
- } break;
case DNSLIB_RDATA_WF_TEXT:
case DNSLIB_RDATA_WF_BINARYWITHLENGTH:
// size stored in the first byte, but the first byte also needs to
// be copied
- memcpy(to, rdata->items[i].raw_data,
- rdata->items[i].raw_data[0] + 1);
- copied += rdata->items[i].raw_data[0] + 1;
- to += rdata->items[i].raw_data[0] + 1;
+ size = rdata->items[i].raw_data[0] + 1;
break;
case DNSLIB_RDATA_WF_BINARY:
case DNSLIB_RDATA_WF_APL: // saved as binary
case DNSLIB_RDATA_WF_IPSECGATEWAY: // saved as binary
// size stored in the first byte, first byte must not be copied
- memcpy(to, &(rdata->items[i].raw_data[1]),
- rdata->items[i].raw_data[0]);
- copied += rdata->items[i].raw_data[0];
- to += rdata->items[i].raw_data[0];
+ size = rdata->items[i].raw_data[0];
+ ++to;
break;
default:
assert(0);
}
+
+ assert(size != 0);
+ assert(copied + size < MAX_RDATA_WIRE_SIZE);
+
+ memcpy(to, from, size);
+ to += size;
+ copied += size;
}
if (copied > buf_size) {
@@ -278,53 +233,54 @@ int dnslib_rdata_compare( const dnslib_rdata_t *r1, const dnslib_rdata_t *r2,
int cmp = 0;
for (int i = 0; i < count; ++i) {
- dnslib_rdata_item_t *item1 = &r2->items[i];
+ dnslib_rdata_item_t *item1 = &r1->items[i];
dnslib_rdata_item_t *item2 = &r2->items[i];
+ const uint8_t *data1 = r1->items[i].raw_data;
+ const uint8_t *data2 = r2->items[i].raw_data;
+ int size1, size2;
+
switch (format[i]) {
case DNSLIB_RDATA_WF_COMPRESSED_DNAME:
case DNSLIB_RDATA_WF_UNCOMPRESSED_DNAME:
case DNSLIB_RDATA_WF_LITERAL_DNAME:
- cmp = dnslib_rdata_compare_binary(
- dnslib_dname_name(item1->dname),
- dnslib_dname_name(item2->dname),
- dnslib_dname_size(item1->dname),
- dnslib_dname_size(item2->dname));
+ data1 = dnslib_dname_name(item1->dname);
+ size1 = dnslib_dname_size(item1->dname);
+ data2 = dnslib_dname_name(item2->dname);
+ size2 = dnslib_dname_size(item2->dname);
break;
case DNSLIB_RDATA_WF_BYTE:
- cmp = (item1->int8 == item2->int8) ? 0 : (
- (r1->items[i].int8 < item2->int8) ? -1 : 1);
+ size1 = size2 = 1;
break;
case DNSLIB_RDATA_WF_SHORT:
- cmp = (item1->int16 == item2->int16) ? 0 : (
- (item1->int16 < item2->int16) ? -1 : 1);
+ size1 = size2 = 2;
break;
case DNSLIB_RDATA_WF_LONG:
- cmp = (item1->int32 == item2->int32) ? 0 : (
- (item1->int32 < item2->int32) ? -1 : 1);
+ size1 = size2 = 4;
break;
case DNSLIB_RDATA_WF_A:
- cmp = dnslib_rdata_compare_binary(item1->a, item2->a, 4, 4);
+ size1 = size2 = 4;
break;
case DNSLIB_RDATA_WF_AAAA:
- cmp = dnslib_rdata_compare_binary(item1->raw_data, item2->raw_data,
- 16, 16);
+ size1 = size2 = 16;
break;
case DNSLIB_RDATA_WF_TEXT:
case DNSLIB_RDATA_WF_BINARYWITHLENGTH:
- cmp = dnslib_rdata_compare_binary(&item1->raw_data[1],
- &item2->raw_data[1], (int)item1->raw_data[0],
- (int)item2->raw_data[0]);
+ size1 = (int)item1->raw_data[0] + 1;
+ size2 = (int)item1->raw_data[0] + 1;
break;
case DNSLIB_RDATA_WF_BINARY:
case DNSLIB_RDATA_WF_APL: // saved as binary
case DNSLIB_RDATA_WF_IPSECGATEWAY: // saved as binary
- cmp = dnslib_rdata_compare_binary(item1->a, item2->a, -1, -1);
+ size1 = -1;
+ size2 = -1;
break;
default:
assert(0);
}
+ cmp = dnslib_rdata_compare_binary(data1, data2, size1, size2);
+
if (cmp != 0) {
return cmp;
}
diff --git a/src/dnslib/rdata.h b/src/dnslib/rdata.h
index 1523f8e70..e73063e8c 100644
--- a/src/dnslib/rdata.h
+++ b/src/dnslib/rdata.h
@@ -27,16 +27,16 @@
*/
union dnslib_rdata_item {
dnslib_dname_t *dname; /*!< RDATA item represented as a domain name. */
- uint8_t int8; /*!< 8bit unsigned integer */
- uint16_t int16; /*!< 16bit unsigned integer */
- uint32_t int32; /*!< 32bit unsigned integer */
- uint8_t a[4]; /*!< A address - four 8bit integers */
+
/*!
* \brief RDATA item represented as raw array of octets.
*
- * In most cases the first octet will be the length of the array. The only
- * now known exception will be when storing AAAA address which has known
- * length (sixteen 8bit integers), so there is no need to store the lenght.
+ * In some cases the first octet will be the length of the array.
+ * In other, the size is determined by the type (i.e. 4 bytes in case of
+ * IPv4 address).
+ *
+ * In some cases this length is also used in the wire format of RDATA
+ * (e.g. character-data as defined in RFC1035).
*/
uint8_t *raw_data;
};
--
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