Пример #1
0
/**
 * Fill CH class answer into buffer. Keeps query.
 * @param pkt: buffer
 * @param str: string to put into text record (<255).
 * @param edns: edns reply information.
 * @param worker: worker with scratch region.
 */
static void
chaos_replystr(sldns_buffer* pkt, const char* str, struct edns_data* edns,
	struct worker* worker)
{
	size_t len = strlen(str);
	unsigned int rd = LDNS_RD_WIRE(sldns_buffer_begin(pkt));
	unsigned int cd = LDNS_CD_WIRE(sldns_buffer_begin(pkt));
	if(len>255) len=255; /* cap size of TXT record */
	sldns_buffer_clear(pkt);
	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip id */
	sldns_buffer_write_u16(pkt, (uint16_t)(BIT_QR|BIT_RA));
	if(rd) LDNS_RD_SET(sldns_buffer_begin(pkt));
	if(cd) LDNS_CD_SET(sldns_buffer_begin(pkt));
	sldns_buffer_write_u16(pkt, 1); /* qdcount */
	sldns_buffer_write_u16(pkt, 1); /* ancount */
	sldns_buffer_write_u16(pkt, 0); /* nscount */
	sldns_buffer_write_u16(pkt, 0); /* arcount */
	(void)query_dname_len(pkt); /* skip qname */
	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qtype */
	sldns_buffer_skip(pkt, (ssize_t)sizeof(uint16_t)); /* skip qclass */
	sldns_buffer_write_u16(pkt, 0xc00c); /* compr ptr to query */
	sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_TXT);
	sldns_buffer_write_u16(pkt, LDNS_RR_CLASS_CH);
	sldns_buffer_write_u32(pkt, 0); /* TTL */
	sldns_buffer_write_u16(pkt, sizeof(uint8_t) + len);
	sldns_buffer_write_u8(pkt, len);
	sldns_buffer_write(pkt, str, len);
	sldns_buffer_flip(pkt);
	edns->edns_version = EDNS_ADVERTISED_VERSION;
	edns->udp_size = EDNS_ADVERTISED_SIZE;
	edns->bits &= EDNS_DO;
	if(!edns_opt_inplace_reply(edns, worker->scratchpad))
		edns->opt_list = NULL;
	attach_edns_record(pkt, edns);
}
Пример #2
0
/** store rrset in buffer in wireformat, return RETVAL_* */
static int
packed_rrset_encode(struct ub_packed_rrset_key* key, sldns_buffer* pkt, 
	uint16_t* num_rrs, time_t timenow, struct regional* region,
	int do_data, int do_sig, struct compress_tree_node** tree,
	sldns_pkt_section s, uint16_t qtype, int dnssec, size_t rr_offset)
{
	size_t i, j, owner_pos;
	int r, owner_labs;
	uint16_t owner_ptr = 0;
	struct packed_rrset_data* data = (struct packed_rrset_data*)
		key->entry.data;
	
	/* does this RR type belong in the answer? */
	if(!rrset_belongs_in_reply(s, ntohs(key->rk.type), qtype, dnssec))
		return RETVAL_OK;

	owner_labs = dname_count_labels(key->rk.dname);
	owner_pos = sldns_buffer_position(pkt);

	if(do_data) {
		const sldns_rr_descriptor* c = type_rdata_compressable(key);
		for(i=0; i<data->count; i++) {
			/* rrset roundrobin */
			j = (i + rr_offset) % data->count;
			if((r=compress_owner(key, pkt, region, tree, 
				owner_pos, &owner_ptr, owner_labs))
				!= RETVAL_OK)
				return r;
			sldns_buffer_write(pkt, &key->rk.type, 2);
			sldns_buffer_write(pkt, &key->rk.rrset_class, 2);
			if(data->rr_ttl[j] < timenow)
				sldns_buffer_write_u32(pkt, 0);
			else 	sldns_buffer_write_u32(pkt, 
					data->rr_ttl[j]-timenow);
			if(c) {
				if((r=compress_rdata(pkt, data->rr_data[j],
					data->rr_len[j], region, tree, c))
					!= RETVAL_OK)
					return r;
			} else {
				if(sldns_buffer_remaining(pkt) < data->rr_len[j])
					return RETVAL_TRUNC;
				sldns_buffer_write(pkt, data->rr_data[j],
					data->rr_len[j]);
			}
		}
	}
	/* insert rrsigs */
	if(do_sig && dnssec) {
		size_t total = data->count+data->rrsig_count;
		for(i=data->count; i<total; i++) {
			if(owner_ptr && owner_labs != 1) {
				if(sldns_buffer_remaining(pkt) <
					2+4+4+data->rr_len[i]) 
					return RETVAL_TRUNC;
				sldns_buffer_write(pkt, &owner_ptr, 2);
			} else {
				if((r=compress_any_dname(key->rk.dname, 
					pkt, owner_labs, region, tree))
					!= RETVAL_OK)
					return r;
				if(sldns_buffer_remaining(pkt) < 
					4+4+data->rr_len[i])
					return RETVAL_TRUNC;
			}
			sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_RRSIG);
			sldns_buffer_write(pkt, &key->rk.rrset_class, 2);
			if(data->rr_ttl[i] < timenow)
				sldns_buffer_write_u32(pkt, 0);
			else 	sldns_buffer_write_u32(pkt, 
					data->rr_ttl[i]-timenow);
			/* rrsig rdata cannot be compressed, perform 100+ byte
			 * memcopy. */
			sldns_buffer_write(pkt, data->rr_data[i],
				data->rr_len[i]);
		}
	}
	/* change rrnum only after we are sure it fits */
	if(do_data)
		*num_rrs += data->count;
	if(do_sig && dnssec)
		*num_rrs += data->rrsig_count;

	return RETVAL_OK;
}