Esempio n. 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);
}
Esempio n. 2
0
void 
qinfo_query_encode(sldns_buffer* pkt, struct query_info* qinfo)
{
	uint16_t flags = 0; /* QUERY, NOERROR */
	sldns_buffer_clear(pkt);
	log_assert(sldns_buffer_remaining(pkt) >= 12+255+4/*max query*/);
	sldns_buffer_skip(pkt, 2); /* id done later */
	sldns_buffer_write_u16(pkt, flags);
	sldns_buffer_write_u16(pkt, 1); /* query count */
	sldns_buffer_write(pkt, "\000\000\000\000\000\000", 6); /* counts */
	sldns_buffer_write(pkt, qinfo->qname, qinfo->qname_len);
	sldns_buffer_write_u16(pkt, qinfo->qtype);
	sldns_buffer_write_u16(pkt, qinfo->qclass);
	sldns_buffer_flip(pkt);
}
Esempio n. 3
0
/** compress a domain name */
static int
write_compressed_dname(sldns_buffer* pkt, uint8_t* dname, int labs,
	struct compress_tree_node* p)
{
	/* compress it */
	int labcopy = labs - p->labs;
	uint8_t lablen;
	uint16_t ptr;

	if(labs == 1) {
		/* write root label */
		if(sldns_buffer_remaining(pkt) < 1)
			return 0;
		sldns_buffer_write_u8(pkt, 0);
		return 1;
	}

	/* copy the first couple of labels */
	while(labcopy--) {
		lablen = *dname++;
		if(sldns_buffer_remaining(pkt) < (size_t)lablen+1)
			return 0;
		sldns_buffer_write_u8(pkt, lablen);
		sldns_buffer_write(pkt, dname, lablen);
		dname += lablen;
	}
	/* insert compression ptr */
	if(sldns_buffer_remaining(pkt) < 2)
		return 0;
	ptr = PTR_CREATE(p->offset);
	sldns_buffer_write_u16(pkt, ptr);
	return 1;
}
Esempio n. 4
0
void 
error_encode(sldns_buffer* buf, int r, struct query_info* qinfo,
	uint16_t qid, uint16_t qflags, struct edns_data* edns)
{
	uint16_t flags;

	sldns_buffer_clear(buf);
	sldns_buffer_write(buf, &qid, sizeof(uint16_t));
	flags = (uint16_t)(BIT_QR | BIT_RA | r); /* QR and retcode*/
	flags |= (qflags & (BIT_RD|BIT_CD)); /* copy RD and CD bit */
	sldns_buffer_write_u16(buf, flags);
	if(qinfo) flags = 1;
	else	flags = 0;
	sldns_buffer_write_u16(buf, flags);
	flags = 0;
	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
	sldns_buffer_write(buf, &flags, sizeof(uint16_t));
	if(qinfo) {
		const uint8_t* qname = qinfo->local_alias ?
			qinfo->local_alias->rrset->rk.dname : qinfo->qname;
		size_t qname_len = qinfo->local_alias ?
			qinfo->local_alias->rrset->rk.dname_len :
			qinfo->qname_len;
		if(sldns_buffer_current(buf) == qname)
			sldns_buffer_skip(buf, (ssize_t)qname_len);
		else	sldns_buffer_write(buf, qname, qname_len);
		sldns_buffer_write_u16(buf, qinfo->qtype);
		sldns_buffer_write_u16(buf, qinfo->qclass);
	}
	sldns_buffer_flip(buf);
	if(edns) {
		struct edns_data es = *edns;
		es.edns_version = EDNS_ADVERTISED_VERSION;
		es.udp_size = EDNS_ADVERTISED_SIZE;
		es.ext_rcode = 0;
		es.bits &= EDNS_DO;
		if(sldns_buffer_limit(buf) + calc_edns_field_size(&es) >
			edns->udp_size)
			return;
		attach_edns_record(buf, &es);
	}
}
Esempio n. 5
0
void 
qinfo_query_encode(sldns_buffer* pkt, struct query_info* qinfo)
{
	uint16_t flags = 0; /* QUERY, NOERROR */
	const uint8_t* qname = qinfo->local_alias ?
		qinfo->local_alias->rrset->rk.dname : qinfo->qname;
	size_t qname_len = qinfo->local_alias ?
		qinfo->local_alias->rrset->rk.dname_len : qinfo->qname_len;
	sldns_buffer_clear(pkt);
	log_assert(sldns_buffer_remaining(pkt) >= 12+255+4/*max query*/);
	sldns_buffer_skip(pkt, 2); /* id done later */
	sldns_buffer_write_u16(pkt, flags);
	sldns_buffer_write_u16(pkt, 1); /* query count */
	sldns_buffer_write(pkt, "\000\000\000\000\000\000", 6); /* counts */
	sldns_buffer_write(pkt, qname, qname_len);
	sldns_buffer_write_u16(pkt, qinfo->qtype);
	sldns_buffer_write_u16(pkt, qinfo->qclass);
	sldns_buffer_flip(pkt);
}
Esempio n. 6
0
/** store query section in wireformat buffer, return RETVAL */
static int
insert_query(struct query_info* qinfo, struct compress_tree_node** tree, 
	sldns_buffer* buffer, struct regional* region)
{
	if(sldns_buffer_remaining(buffer) < 
		qinfo->qname_len+sizeof(uint16_t)*2)
		return RETVAL_TRUNC; /* buffer too small */
	/* the query is the first name inserted into the tree */
	if(!compress_tree_store(qinfo->qname, 
		dname_count_labels(qinfo->qname), 
		sldns_buffer_position(buffer), region, NULL, tree))
		return RETVAL_OUTMEM;
	if(sldns_buffer_current(buffer) == qinfo->qname)
		sldns_buffer_skip(buffer, (ssize_t)qinfo->qname_len);
	else	sldns_buffer_write(buffer, qinfo->qname, qinfo->qname_len);
	sldns_buffer_write_u16(buffer, qinfo->qtype);
	sldns_buffer_write_u16(buffer, qinfo->qclass);
	return RETVAL_OK;
}
Esempio n. 7
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void
attach_edns_record(sldns_buffer* pkt, struct edns_data* edns)
{
	size_t len;
	size_t rdatapos;
	struct edns_option* opt;
	if(!edns || !edns->edns_present)
		return;
	/* inc additional count */
	sldns_buffer_write_u16_at(pkt, 10,
		sldns_buffer_read_u16_at(pkt, 10) + 1);
	len = sldns_buffer_limit(pkt);
	sldns_buffer_clear(pkt);
	sldns_buffer_set_position(pkt, len);
	/* write EDNS record */
	sldns_buffer_write_u8(pkt, 0); /* '.' label */
	sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_OPT); /* type */
	sldns_buffer_write_u16(pkt, edns->udp_size); /* class */
	sldns_buffer_write_u8(pkt, edns->ext_rcode); /* ttl */
	sldns_buffer_write_u8(pkt, edns->edns_version);
	sldns_buffer_write_u16(pkt, edns->bits);
	rdatapos = sldns_buffer_position(pkt);
	sldns_buffer_write_u16(pkt, 0); /* rdatalen */
	/* write rdata */
	for(opt=edns->opt_list; opt; opt=opt->next) {
		sldns_buffer_write_u16(pkt, opt->opt_code);
		sldns_buffer_write_u16(pkt, opt->opt_len);
		if(opt->opt_len != 0)
			sldns_buffer_write(pkt, opt->opt_data, opt->opt_len);
	}
	if(edns->opt_list)
		sldns_buffer_write_u16_at(pkt, rdatapos, 
			sldns_buffer_position(pkt)-rdatapos-2);
	sldns_buffer_flip(pkt);
}
Esempio n. 8
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void
attach_edns_record(sldns_buffer* pkt, struct edns_data* edns)
{
	size_t len;
	if(!edns || !edns->edns_present)
		return;
	/* inc additional count */
	sldns_buffer_write_u16_at(pkt, 10,
		sldns_buffer_read_u16_at(pkt, 10) + 1);
	len = sldns_buffer_limit(pkt);
	sldns_buffer_clear(pkt);
	sldns_buffer_set_position(pkt, len);
	/* write EDNS record */
	sldns_buffer_write_u8(pkt, 0); /* '.' label */
	sldns_buffer_write_u16(pkt, LDNS_RR_TYPE_OPT); /* type */
	sldns_buffer_write_u16(pkt, edns->udp_size); /* class */
	sldns_buffer_write_u8(pkt, edns->ext_rcode); /* ttl */
	sldns_buffer_write_u8(pkt, edns->edns_version);
	sldns_buffer_write_u16(pkt, edns->bits);
	sldns_buffer_write_u16(pkt, 0); /* rdatalen */
	sldns_buffer_flip(pkt);
}
Esempio n. 9
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struct serviced_query* outnet_serviced_query(struct outside_network* outnet,
        uint8_t* qname, size_t qnamelen, uint16_t qtype, uint16_t qclass,
	uint16_t flags, int dnssec, int ATTR_UNUSED(want_dnssec),
	int ATTR_UNUSED(tcp_upstream), int ATTR_UNUSED(ssl_upstream),
	struct sockaddr_storage* addr, socklen_t addrlen, uint8_t* zone,
	size_t zonelen, comm_point_callback_t* callback, void* callback_arg,
	sldns_buffer* ATTR_UNUSED(buff))
{
	struct replay_runtime* runtime = (struct replay_runtime*)outnet->base;
	struct fake_pending* pend = (struct fake_pending*)calloc(1,
		sizeof(struct fake_pending));
	char z[256];
	log_assert(pend);
	log_nametypeclass(VERB_OPS, "pending serviced query", 
		qname, qtype, qclass);
	dname_str(zone, z);
	verbose(VERB_OPS, "pending serviced query zone %s flags%s%s%s%s", 
		z, (flags&BIT_RD)?" RD":"", (flags&BIT_CD)?" CD":"",
		(flags&~(BIT_RD|BIT_CD))?" MORE":"", (dnssec)?" DO":"");

	/* create packet with EDNS */
	pend->buffer = sldns_buffer_new(512);
	log_assert(pend->buffer);
	sldns_buffer_write_u16(pend->buffer, 0); /* id */
	sldns_buffer_write_u16(pend->buffer, flags);
	sldns_buffer_write_u16(pend->buffer, 1); /* qdcount */
	sldns_buffer_write_u16(pend->buffer, 0); /* ancount */
	sldns_buffer_write_u16(pend->buffer, 0); /* nscount */
	sldns_buffer_write_u16(pend->buffer, 0); /* arcount */
	sldns_buffer_write(pend->buffer, qname, qnamelen);
	sldns_buffer_write_u16(pend->buffer, qtype);
	sldns_buffer_write_u16(pend->buffer, qclass);
	sldns_buffer_flip(pend->buffer);
	if(1) {
		/* add edns */
		struct edns_data edns;
		edns.edns_present = 1;
		edns.ext_rcode = 0;
		edns.edns_version = EDNS_ADVERTISED_VERSION;
		edns.udp_size = EDNS_ADVERTISED_SIZE;
		edns.bits = 0;
		if(dnssec)
			edns.bits = EDNS_DO;
		attach_edns_record(pend->buffer, &edns);
	}
	memcpy(&pend->addr, addr, addrlen);
	pend->addrlen = addrlen;
	pend->zone = memdup(zone, zonelen);
	pend->zonelen = zonelen;
	pend->qtype = (int)qtype;
	log_assert(pend->zone);
	pend->callback = callback;
	pend->cb_arg = callback_arg;
	pend->timeout = UDP_AUTH_QUERY_TIMEOUT;
	pend->transport = transport_udp; /* pretend UDP */
	pend->pkt = NULL;
	pend->runtime = runtime;
	pend->serviced = 1;
	pend->pkt_len = sldns_buffer_limit(pend->buffer);
	pend->pkt = memdup(sldns_buffer_begin(pend->buffer), pend->pkt_len);
	if(!pend->pkt) fatal_exit("out of memory");
	/*log_pkt("pending serviced query: ", pend->pkt, pend->pkt_len);*/

	/* see if it matches the current moment */
	if(runtime->now && runtime->now->evt_type == repevt_back_query &&
		(runtime->now->addrlen == 0 || sockaddr_cmp(
			&runtime->now->addr, runtime->now->addrlen,
			&pend->addr, pend->addrlen) == 0) &&
		find_match(runtime->now->match, pend->pkt, pend->pkt_len,
			pend->transport)) {
		log_info("testbound: matched pending to event. "
			"advance time between events.");
		log_info("testbound: do STEP %d %s", runtime->now->time_step,
			repevt_string(runtime->now->evt_type));
		advance_moment(runtime);
		/* still create the pending, because we need it to callback */
	} 
	log_info("testbound: created fake pending");
	/* add to list */
	pend->next = runtime->pending_list;
	runtime->pending_list = pend;
	return (struct serviced_query*)pend;
}
Esempio n. 10
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int 
reply_info_encode(struct query_info* qinfo, struct reply_info* rep, 
	uint16_t id, uint16_t flags, sldns_buffer* buffer, time_t timenow, 
	struct regional* region, uint16_t udpsize, int dnssec)
{
	uint16_t ancount=0, nscount=0, arcount=0;
	struct compress_tree_node* tree = 0;
	int r;
	size_t rr_offset; 

	sldns_buffer_clear(buffer);
	if(udpsize < sldns_buffer_limit(buffer))
		sldns_buffer_set_limit(buffer, udpsize);
	if(sldns_buffer_remaining(buffer) < LDNS_HEADER_SIZE)
		return 0;

	sldns_buffer_write(buffer, &id, sizeof(uint16_t));
	sldns_buffer_write_u16(buffer, flags);
	sldns_buffer_write_u16(buffer, rep->qdcount);
	/* set an, ns, ar counts to zero in case of small packets */
	sldns_buffer_write(buffer, "\000\000\000\000\000\000", 6);

	/* insert query section */
	if(rep->qdcount) {
		if((r=insert_query(qinfo, &tree, buffer, region)) != 
			RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* create truncated message */
				sldns_buffer_write_u16_at(buffer, 4, 0);
				LDNS_TC_SET(sldns_buffer_begin(buffer));
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
	}
	/* roundrobin offset. using query id for random number.  With ntohs
	 * for different roundrobins for sequential id client senders. */
	rr_offset = RRSET_ROUNDROBIN?ntohs(id):0;

	/* "prepend" any local alias records in the answer section if this
	 * response is supposed to be authoritative.  Currently it should
	 * be a single CNAME record (sanity-checked in worker_handle_request())
	 * but it can be extended if and when we support more variations of
	 * aliases. */
	if(qinfo->local_alias && (flags & BIT_AA)) {
		struct reply_info arep;
		time_t timezero = 0; /* to use the 'authoritative' TTL */
		memset(&arep, 0, sizeof(arep));
		arep.flags = rep->flags;
		arep.an_numrrsets = 1;
		arep.rrset_count = 1;
		arep.rrsets = &qinfo->local_alias->rrset;
		if((r=insert_section(&arep, 1, &ancount, buffer, 0,
			timezero, region, &tree, LDNS_SECTION_ANSWER,
			qinfo->qtype, dnssec, rr_offset)) != RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* create truncated message */
				sldns_buffer_write_u16_at(buffer, 6, ancount);
				LDNS_TC_SET(sldns_buffer_begin(buffer));
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
	}

	/* insert answer section */
	if((r=insert_section(rep, rep->an_numrrsets, &ancount, buffer, 
		0, timenow, region, &tree, LDNS_SECTION_ANSWER, qinfo->qtype, 
		dnssec, rr_offset)) != RETVAL_OK) {
		if(r == RETVAL_TRUNC) {
			/* create truncated message */
			sldns_buffer_write_u16_at(buffer, 6, ancount);
			LDNS_TC_SET(sldns_buffer_begin(buffer));
			sldns_buffer_flip(buffer);
			return 1;
		}
		return 0;
	}
	sldns_buffer_write_u16_at(buffer, 6, ancount);

	/* if response is positive answer, auth/add sections are not required */
	if( ! (MINIMAL_RESPONSES && positive_answer(rep, qinfo->qtype)) ) {
		/* insert auth section */
		if((r=insert_section(rep, rep->ns_numrrsets, &nscount, buffer, 
			rep->an_numrrsets, timenow, region, &tree,
			LDNS_SECTION_AUTHORITY, qinfo->qtype,
			dnssec, rr_offset)) != RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* create truncated message */
				sldns_buffer_write_u16_at(buffer, 8, nscount);
				LDNS_TC_SET(sldns_buffer_begin(buffer));
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
		sldns_buffer_write_u16_at(buffer, 8, nscount);

		/* insert add section */
		if((r=insert_section(rep, rep->ar_numrrsets, &arcount, buffer, 
			rep->an_numrrsets + rep->ns_numrrsets, timenow, region, 
			&tree, LDNS_SECTION_ADDITIONAL, qinfo->qtype, 
			dnssec, rr_offset)) != RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* no need to set TC bit, this is the additional */
				sldns_buffer_write_u16_at(buffer, 10, arcount);
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
		sldns_buffer_write_u16_at(buffer, 10, arcount);
	}
	sldns_buffer_flip(buffer);
	return 1;
}
Esempio n. 11
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/** 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;
}
Esempio n. 12
0
/** setup looped dname and out-of-bounds dname ptr */
static void
dname_setup_bufs(sldns_buffer* loopbuf, sldns_buffer* boundbuf)
{
	sldns_buffer_write_u16(loopbuf, 0xd54d);  /* id */
	sldns_buffer_write_u16(loopbuf, 0x12);    /* flags  */
	sldns_buffer_write_u16(loopbuf, 1);       /* qdcount */
	sldns_buffer_write_u16(loopbuf, 0);       /* ancount */
	sldns_buffer_write_u16(loopbuf, 0);       /* nscount */
	sldns_buffer_write_u16(loopbuf, 0);       /* arcount */
	sldns_buffer_write_u8(loopbuf, 0xc0); /* PTR back at itself */
	sldns_buffer_write_u8(loopbuf, 0x0c);
	sldns_buffer_flip(loopbuf);

	sldns_buffer_write_u16(boundbuf, 0xd54d);  /* id */
	sldns_buffer_write_u16(boundbuf, 0x12);    /* flags  */
	sldns_buffer_write_u16(boundbuf, 1);       /* qdcount */
	sldns_buffer_write_u16(boundbuf, 0);       /* ancount */
	sldns_buffer_write_u16(boundbuf, 0);       /* nscount */
	sldns_buffer_write_u16(boundbuf, 0);       /* arcount */
	sldns_buffer_write_u8(boundbuf, 0x01); /* len=1 */
	sldns_buffer_write_u8(boundbuf, (uint8_t)'A'); /* A. label */
	sldns_buffer_write_u8(boundbuf, 0xc0); /* PTR out of bounds */
	sldns_buffer_write_u8(boundbuf, 0xcc);
	sldns_buffer_flip(boundbuf);
}
Esempio n. 13
0
int 
reply_info_encode(struct query_info* qinfo, struct reply_info* rep, 
	uint16_t id, uint16_t flags, sldns_buffer* buffer, time_t timenow, 
	struct regional* region, uint16_t udpsize, int dnssec)
{
	uint16_t ancount=0, nscount=0, arcount=0;
	struct compress_tree_node* tree = 0;
	int r;
	size_t rr_offset; 

	sldns_buffer_clear(buffer);
	if(udpsize < sldns_buffer_limit(buffer))
		sldns_buffer_set_limit(buffer, udpsize);
	if(sldns_buffer_remaining(buffer) < LDNS_HEADER_SIZE)
		return 0;

	sldns_buffer_write(buffer, &id, sizeof(uint16_t));
	sldns_buffer_write_u16(buffer, flags);
	sldns_buffer_write_u16(buffer, rep->qdcount);
	/* set an, ns, ar counts to zero in case of small packets */
	sldns_buffer_write(buffer, "\000\000\000\000\000\000", 6);

	/* insert query section */
	if(rep->qdcount) {
		if((r=insert_query(qinfo, &tree, buffer, region)) != 
			RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* create truncated message */
				sldns_buffer_write_u16_at(buffer, 4, 0);
				LDNS_TC_SET(sldns_buffer_begin(buffer));
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
	}
	/* roundrobin offset. using query id for random number.  With ntohs
	 * for different roundrobins for sequential id client senders. */
	rr_offset = RRSET_ROUNDROBIN?ntohs(id):0;

	/* insert answer section */
	if((r=insert_section(rep, rep->an_numrrsets, &ancount, buffer, 
		0, timenow, region, &tree, LDNS_SECTION_ANSWER, qinfo->qtype, 
		dnssec, rr_offset)) != RETVAL_OK) {
		if(r == RETVAL_TRUNC) {
			/* create truncated message */
			sldns_buffer_write_u16_at(buffer, 6, ancount);
			LDNS_TC_SET(sldns_buffer_begin(buffer));
			sldns_buffer_flip(buffer);
			return 1;
		}
		return 0;
	}
	sldns_buffer_write_u16_at(buffer, 6, ancount);

	/* if response is positive answer, auth/add sections are not required */
	if( ! (MINIMAL_RESPONSES && positive_answer(rep, qinfo->qtype)) ) {
		/* insert auth section */
		if((r=insert_section(rep, rep->ns_numrrsets, &nscount, buffer, 
			rep->an_numrrsets, timenow, region, &tree,
			LDNS_SECTION_AUTHORITY, qinfo->qtype,
			dnssec, rr_offset)) != RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* create truncated message */
				sldns_buffer_write_u16_at(buffer, 8, nscount);
				LDNS_TC_SET(sldns_buffer_begin(buffer));
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
		sldns_buffer_write_u16_at(buffer, 8, nscount);

		/* insert add section */
		if((r=insert_section(rep, rep->ar_numrrsets, &arcount, buffer, 
			rep->an_numrrsets + rep->ns_numrrsets, timenow, region, 
			&tree, LDNS_SECTION_ADDITIONAL, qinfo->qtype, 
			dnssec, rr_offset)) != RETVAL_OK) {
			if(r == RETVAL_TRUNC) {
				/* no need to set TC bit, this is the additional */
				sldns_buffer_write_u16_at(buffer, 10, arcount);
				sldns_buffer_flip(buffer);
				return 1;
			}
			return 0;
		}
		sldns_buffer_write_u16_at(buffer, 10, arcount);
	}
	sldns_buffer_flip(buffer);
	return 1;
}