static int rrl_clsname(char *dst, size_t maxlen, uint8_t cls,
rrl_req_t *req, const zone_t *zone)
{
/* Fallback zone (for errors etc.) */
const knot_dname_t *dn = (const knot_dname_t*)"\x00";
/* Found associated zone. */
if (zone != NULL) {
dn = zone->name;
}
switch (cls) {
case CLS_ERROR: /* Could be a non-existent zone or garbage. */
case CLS_NXDOMAIN: /* Queries to non-existent names in zone. */
case CLS_WILDCARD: /* Queries to names covered by a wildcard. */
dbg_rrl_verb("%s: using zone/fallback name\n", __func__);
break;
default:
/* Use QNAME */
if (req->query)
dn = knot_pkt_qname(req->query);
break;
}
/* Write to wire */
return knot_dname_to_wire((uint8_t *)dst, dn, maxlen);
}
/**
* Name error response check (RFC4035 3.1.3.2; RFC4035 5.4, bullet 2).
* @note Returned flags must be checked in order to prove denial.
* @param flags Flags to be set according to check outcome.
* @param nsec NSEC RR.
* @param name Name to be checked.
* @param pool
* @return 0 or error code.
*/
static int name_error_response_check_rr(int *flags, const knot_rrset_t *nsec,
const knot_dname_t *name)
{
assert(flags && nsec && name);
if (nsec_nonamematch(nsec, name) == 0) {
*flags |= FLG_NOEXIST_RRSET;
}
/* Try to find parent wildcard that is proved by this NSEC. */
uint8_t namebuf[KNOT_DNAME_MAXLEN];
int ret = knot_dname_to_wire(namebuf, name, sizeof(namebuf));
if (ret < 0)
return ret;
knot_dname_t *ptr = namebuf;
while (ptr[0]) {
/* Remove leftmost label and replace it with '\1*'. */
ptr = (uint8_t *) knot_wire_next_label(ptr, NULL);
*(--ptr) = '*';
*(--ptr) = 1;
/* True if this wildcard provably doesn't exist. */
if (nsec_nonamematch(nsec, ptr) == 0) {
*flags |= FLG_NOEXIST_WILDCARD;
break;
}
/* Remove added leftmost asterisk. */
ptr += 2;
}
return kr_ok();
}
/*----------------------------------------------------------------------------*/
_public_
knot_dname_t *knot_dname_copy_part(const knot_dname_t *name, unsigned len,
mm_ctx_t *mm)
{
if (name == NULL || len == 0)
return NULL;
knot_dname_t *dst = mm_alloc(mm, len);
if (knot_dname_to_wire(dst, name, len) < 1) {
free(dst);
return NULL;
}
return dst;
}
_public_
int knot_pkt_put_question(knot_pkt_t *pkt, const knot_dname_t *qname, uint16_t qclass, uint16_t qtype)
{
if (pkt == NULL || qname == NULL) {
return KNOT_EINVAL;
}
assert(pkt->size == KNOT_WIRE_HEADER_SIZE);
assert(pkt->rrset_count == 0);
/* Copy name wireformat. */
uint8_t *dst = pkt->wire + KNOT_WIRE_HEADER_SIZE;
int qname_len = knot_dname_to_wire(dst, qname, pkt->max_size - pkt->size);
if (qname_len < 0) {
return qname_len;
}
/* Check size limits. */
size_t question_len = 2 * sizeof(uint16_t) + qname_len;
if (qname_len < 0 || pkt->size + question_len > pkt->max_size) {
return KNOT_ESPACE;
}
/* Copy QTYPE & QCLASS */
dst += qname_len;
wire_write_u16(dst, qtype);
dst += sizeof(uint16_t);
wire_write_u16(dst, qclass);
/* Update question count and sizes. */
knot_wire_set_qdcount(pkt->wire, 1);
pkt->size += question_len;
pkt->qname_size = qname_len;
/* Start writing ANSWER. */
return knot_pkt_begin(pkt, KNOT_ANSWER);
}
static int knot_tsig_write_tsig_variables(uint8_t *wire,
const knot_rrset_t *tsig_rr)
{
if (wire == NULL || tsig_rr == NULL) {
dbg_tsig("TSIG: write tsig variables: NULL arguments.\n");
return KNOT_EINVAL;
}
/* Copy TSIG variables - starting with key name. */
const knot_dname_t *tsig_owner = tsig_rr->owner;
if (!tsig_owner) {
dbg_tsig("TSIG: write variables: no owner.\n");
return KNOT_EINVAL;
}
int offset = 0;
offset += knot_dname_to_wire(wire + offset, tsig_owner, KNOT_DNAME_MAXLEN);
/*!< \todo which order? */
/* Copy class. */
knot_wire_write_u16(wire + offset, tsig_rr->rclass);
dbg_tsig_verb("TSIG: write variables: written CLASS: %u - \n",
tsig_rr->rclass);
dbg_tsig_hex_detail((char *)(wire + offset), sizeof(uint16_t));
offset += sizeof(uint16_t);
/* Copy TTL - always 0. */
knot_wire_write_u32(wire + offset, knot_rrset_rr_ttl(tsig_rr, 0));
dbg_tsig_verb("TSIG: write variables: written TTL: %u - \n",
knot_rrset_rr_ttl(tsig_rr, 0));
dbg_tsig_hex_detail((char *)(wire + offset), sizeof(uint32_t));
offset += sizeof(uint32_t);
/* Copy alg name. */
const knot_dname_t *alg_name = tsig_rdata_alg_name(tsig_rr);
if (!alg_name) {
dbg_tsig("TSIG: write variables: no algorithm name.\n");
return KNOT_EINVAL;
}
/* Te algorithm name must be in canonical form, i.e. in lowercase. */
uint8_t *alg_name_wire = wire + offset;
offset += knot_dname_to_wire(alg_name_wire, alg_name, KNOT_DNAME_MAXLEN);
if (knot_dname_to_lower(alg_name_wire) != KNOT_EOK) {
dbg_tsig("TSIG: write variables: cannot convert algorithm "
"to lowercase.\n");
return KNOT_EINVAL;
}
/* Following data are written in network order. */
/* Time signed. */
knot_wire_write_u48(wire + offset, tsig_rdata_time_signed(tsig_rr));
offset += 6;
dbg_tsig_verb("TSIG: write variables: time signed: %"PRIu64" \n",
tsig_rdata_time_signed(tsig_rr));
dbg_tsig_hex_detail((char *)(wire + offset - 6), 6);
/* Fudge. */
knot_wire_write_u16(wire + offset, tsig_rdata_fudge(tsig_rr));
offset += sizeof(uint16_t);
dbg_tsig_verb("TSIG: write variables: fudge: %hu\n",
tsig_rdata_fudge(tsig_rr));
/* TSIG error. */
knot_wire_write_u16(wire + offset, tsig_rdata_error(tsig_rr));
offset += sizeof(uint16_t);
/* Get other data length. */
uint16_t other_data_length = tsig_rdata_other_data_length(tsig_rr);
/* Get other data. */
const uint8_t *other_data = tsig_rdata_other_data(tsig_rr);
if (!other_data) {
dbg_tsig("TSIG: write variables: no other data.\n");
return KNOT_EINVAL;
}
/*
* We cannot write the whole other_data, as it contains its length in
* machine order.
*/
knot_wire_write_u16(wire + offset, other_data_length);
offset += sizeof(uint16_t);
/* Skip the length. */
dbg_tsig_verb("Copying other data.\n");
memcpy(wire + offset, other_data, other_data_length);
return KNOT_EOK;
}