/** * 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); }
/** 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; }