From 6ebfd00ded15413d407aa15ae92ed5d7dd905191 Mon Sep 17 00:00:00 2001
From: Lubos Slovak <lubos.slovak@nic.cz>
Date: Tue, 26 Aug 2014 10:54:37 +0200
Subject: [PATCH] RRSet wire: Unified RDATA-traversing function.
First draft. Requires some optimizations and testing.
---
src/libknot/rrset.c | 139 ++++++++++++++++++++++++++++++++++++++++----
1 file changed, 129 insertions(+), 10 deletions(-)
diff --git a/src/libknot/rrset.c b/src/libknot/rrset.c
index 833f558af..5179c4687 100644
--- a/src/libknot/rrset.c
+++ b/src/libknot/rrset.c
@@ -184,7 +184,7 @@ static int write_rdata_dname(uint8_t **src, size_t *src_avail,
/* Output domain name */
int written = knot_compr_put_dname(dname, *wire, dname_max(*capacity),
- compress ? compr : NULL);
+ compress ? compr : NULL);
if (written < 0) {
assert(written == KNOT_ESPACE);
return written;
@@ -311,6 +311,119 @@ static int write_rdata_block(uint8_t **src, size_t *src_avail,
}
}
+static int compress_dname(uint8_t **src, size_t *src_avail,
+ uint8_t **dst, size_t *dst_avail,
+ knot_compr_t *compr, int compr_hint, int type,
+ knot_rrset_wire_flags_t flags,
+ const uint8_t *pkt_wire)
+{
+ bool compress = (type == KNOT_RDATA_WF_COMPRESSIBLE_DNAME);
+
+ UNUSED(pkt_wire);
+
+ return write_rdata_dname(src, src_avail, dst, dst_avail, compr,
+ compr_hint, compress, flags);
+}
+
+static int decompress_dname(uint8_t **src, size_t *src_avail,
+ uint8_t **dst, size_t *dst_avail,
+ knot_compr_t *compr, int compr_hint, int type,
+ knot_rrset_wire_flags_t flags,
+ const uint8_t *pkt_wire)
+{
+ UNUSED(compr);
+ UNUSED(compr_hint);
+
+ bool decompress = (type == KNOT_RDATA_WF_COMPRESSIBLE_DNAME
+ || type == KNOT_RDATA_WF_DECOMPRESSIBLE_DNAME);
+
+ int ret = knot_dname_wire_check(*src, *src + *src_avail, pkt_wire);
+ if (ret <= 0) {
+ return KNOT_EMALF;
+ }
+
+ size_t dname_size = ret;
+ int written = dname_size;
+
+ if (decompress) {
+ int ret = knot_dname_unpack(*dst, *src, *dst_avail, pkt_wire);
+ if (ret <= 0) {
+ return ret;
+ }
+ written = ret;
+ } else if (dname_size > *dst_avail) {
+ return KNOT_ESPACE;
+ } else {
+ memcpy(*dst, *src, dname_size);
+ }
+
+ /* Post-processing */
+
+ if (flags & KNOT_RRSET_WIRE_CANONICAL) {
+ knot_dname_to_lower(*dst);
+ }
+
+ /* Update buffers */
+
+ *dst += written;
+ *dst_avail -= written;
+
+ *src += dname_size;
+ *src_avail -= dname_size;
+
+ return KNOT_EOK;
+}
+
+typedef int (*dname_callback_t)(uint8_t **, size_t *, uint8_t **, size_t *,
+ knot_compr_t *, int, int,
+ knot_rrset_wire_flags_t, const uint8_t *);
+
+static int traverse_rdata(uint16_t rr_type, uint8_t **src, size_t *src_avail,
+ uint8_t **wire, size_t *capacity, knot_compr_t *compr,
+ int compr_hint, knot_rrset_wire_flags_t flags,
+ uint8_t *pkt_wire, dname_callback_t dname_callback)
+{
+ const rdata_descriptor_t *desc = knot_get_rdata_descriptor(rr_type);
+
+ int ret = KNOT_EOK;
+
+ for (int i = 0; desc->block_types[i] != KNOT_RDATA_WF_END; i++) {
+ int type = desc->block_types[i];
+
+ switch (type) {
+ case KNOT_RDATA_WF_COMPRESSIBLE_DNAME:
+ case KNOT_RDATA_WF_DECOMPRESSIBLE_DNAME:
+ case KNOT_RDATA_WF_FIXED_DNAME:
+ ret = dname_callback(src, src_avail, wire, capacity,
+ compr, compr_hint, type, flags,
+ pkt_wire);
+ break;
+ case KNOT_RDATA_WF_NAPTR_HEADER:
+ ret = write_rdata_naptr(src, src_avail, wire, capacity);
+ break;
+ case KNOT_RDATA_WF_REMAINDER:
+ ret = write_rdata_fixed(src, src_avail, wire, capacity,
+ *src_avail);
+ break;
+ default:
+ /* Fixed size block */
+ assert(type > 0);
+ ret = write_rdata_fixed(src, src_avail, wire, capacity,
+ type);
+ }
+
+ /* TODO: unify the write_rdata_... functions - do the copying
+ * after the switch, before that just count the size.
+ */
+
+ if (ret != KNOT_EOK) {
+ return ret;
+ }
+ }
+
+ return KNOT_EOK;
+}
+
/*!
* \brief Write RDLENGTH and RDATA fields of a RR in a wire.
*/
@@ -345,15 +458,21 @@ static int write_rdata(const knot_rrset_t *rrset, uint16_t rrset_index,
size_t src_avail = knot_rdata_rdlen(rdata);
if (src_avail > 0) {
/* Only write non-empty data. */
- const rdata_descriptor_t *desc =
- knot_get_rdata_descriptor(rrset->type);
- for (int i = 0; desc->block_types[i] != KNOT_RDATA_WF_END; i++) {
- int type = desc->block_types[i];
- int ret = write_rdata_block(&src, &src_avail, wire, capacity,
- type, compr, compr_hint, flags);
- if (ret != KNOT_EOK) {
- return ret;
- }
+// const rdata_descriptor_t *desc =
+// knot_get_rdata_descriptor(rrset->type);
+// for (int i = 0; desc->block_types[i] != KNOT_RDATA_WF_END; i++) {
+// int type = desc->block_types[i];
+// int ret = write_rdata_block(&src, &src_avail, wire, capacity,
+// type, compr, compr_hint, flags);
+// if (ret != KNOT_EOK) {
+// return ret;
+// }
+// }
+ int ret = traverse_rdata(rrset->type, &src, &src_avail, wire,
+ capacity, compr, compr_hint, flags,
+ compr->wire, compress_dname);
+ if (ret != KNOT_EOK) {
+ return ret;
}
}
--
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