/** convert and print rdata */
static void
print_rd(int t, char* data, size_t len)
{
size_t i, pos = 0;
uint8_t* rd = (uint8_t*)malloc(len+2);
ldns_rr* rr = ldns_rr_new();
ldns_status status;
if(!rd || !rr) {
fprintf(stderr, "out of memory");
exit(1);
}
ldns_rr_set_type(rr, t);
ldns_write_uint16(rd, len);
memmove(rd+2, data, len);
ldns_rr_set_owner(rr, NULL);
status = ldns_wire2rdf(rr, rd, len+2, &pos);
if(status != LDNS_STATUS_OK) {
free(rd);
ldns_rr_free(rr);
printf("error_printing_data");
return;
}
for(i=0; i<ldns_rr_rd_count(rr); i++) {
printf(" ");
ldns_rdf_print(stdout, ldns_rr_rdf(rr, i));
}
ldns_rr_free(rr);
free(rd);
}
/** synthesize a CNAME rrset */
static struct rrset_parse*
synth_cname_rrset(uint8_t** sname, size_t* snamelen, uint8_t* alias,
size_t aliaslen, struct regional* region, struct msg_parse* msg,
struct rrset_parse* rrset, struct rrset_parse* prev,
struct rrset_parse* nx, ldns_buffer* pkt)
{
struct rrset_parse* cn = (struct rrset_parse*)regional_alloc(region,
sizeof(struct rrset_parse));
if(!cn)
return NULL;
memset(cn, 0, sizeof(*cn));
cn->rr_first = (struct rr_parse*)regional_alloc(region,
sizeof(struct rr_parse));
if(!cn->rr_first)
return NULL;
cn->rr_last = cn->rr_first;
/* CNAME from sname to alias */
cn->dname = (uint8_t*)regional_alloc(region, *snamelen);
if(!cn->dname)
return NULL;
dname_pkt_copy(pkt, cn->dname, *sname);
cn->dname_len = *snamelen;
cn->type = LDNS_RR_TYPE_CNAME;
cn->section = rrset->section;
cn->rrset_class = rrset->rrset_class;
cn->rr_count = 1;
cn->size = sizeof(uint16_t) + aliaslen;
cn->hash=pkt_hash_rrset(pkt, cn->dname, cn->type, cn->rrset_class, 0);
/* allocate TTL + rdatalen + uncompressed dname */
memset(cn->rr_first, 0, sizeof(struct rr_parse));
cn->rr_first->outside_packet = 1;
cn->rr_first->ttl_data = (uint8_t*)regional_alloc(region,
sizeof(uint32_t)+sizeof(uint16_t)+aliaslen);
if(!cn->rr_first->ttl_data)
return NULL;
ldns_write_uint32(cn->rr_first->ttl_data, 0); /* TTL = 0 */
ldns_write_uint16(cn->rr_first->ttl_data+4, aliaslen);
memmove(cn->rr_first->ttl_data+6, alias, aliaslen);
cn->rr_first->size = sizeof(uint16_t)+aliaslen;
/* link it in */
cn->rrset_all_next = nx;
if(prev)
prev->rrset_all_next = cn;
else msg->rrset_first = cn;
if(nx == NULL)
msg->rrset_last = cn;
msg->rrset_count ++;
msg->an_rrsets++;
/* it is not inserted in the msg hashtable. */
*sname = cn->rr_first->ttl_data + sizeof(uint32_t)+sizeof(uint16_t);
*snamelen = aliaslen;
return cn;
}
ssize_t
ldns_tcp_send_query(ldns_buffer *qbin, int sockfd,
const struct sockaddr_storage *to, socklen_t tolen)
{
uint8_t *sendbuf;
ssize_t bytes;
/* add length of packet */
sendbuf = LDNS_XMALLOC(uint8_t, ldns_buffer_position(qbin) + 2);
if(!sendbuf) return 0;
ldns_write_uint16(sendbuf, ldns_buffer_position(qbin));
memcpy(sendbuf + 2, ldns_buffer_begin(qbin), ldns_buffer_position(qbin));
bytes = sendto(sockfd, (void*)sendbuf,
ldns_buffer_position(qbin) + 2, 0, (struct sockaddr *)to, tolen);
LDNS_FREE(sendbuf);
if (bytes == -1 || (size_t) bytes != ldns_buffer_position(qbin) + 2 ) {
return 0;
}
return bytes;
}
/*
* Makes an exact copy of the wire, but with the tsig rr removed
*/
static uint8_t *
ldns_tsig_prepare_pkt_wire(uint8_t *wire, size_t wire_len, size_t *result_len)
{
uint8_t *wire2 = NULL;
uint16_t qd_count;
uint16_t an_count;
uint16_t ns_count;
uint16_t ar_count;
ldns_rr *rr;
size_t pos;
uint16_t i;
ldns_status status;
if(wire_len < LDNS_HEADER_SIZE) {
return NULL;
}
/* fake parse the wire */
qd_count = LDNS_QDCOUNT(wire);
an_count = LDNS_ANCOUNT(wire);
ns_count = LDNS_NSCOUNT(wire);
ar_count = LDNS_ARCOUNT(wire);
if (ar_count > 0) {
ar_count--;
} else {
return NULL;
}
pos = LDNS_HEADER_SIZE;
for (i = 0; i < qd_count; i++) {
status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_QUESTION);
if (status != LDNS_STATUS_OK) {
return NULL;
}
ldns_rr_free(rr);
}
for (i = 0; i < an_count; i++) {
status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_ANSWER);
if (status != LDNS_STATUS_OK) {
return NULL;
}
ldns_rr_free(rr);
}
for (i = 0; i < ns_count; i++) {
status = ldns_wire2rr(&rr, wire, wire_len, &pos, LDNS_SECTION_AUTHORITY);
if (status != LDNS_STATUS_OK) {
return NULL;
}
ldns_rr_free(rr);
}
for (i = 0; i < ar_count; i++) {
status = ldns_wire2rr(&rr, wire, wire_len, &pos,
LDNS_SECTION_ADDITIONAL);
if (status != LDNS_STATUS_OK) {
return NULL;
}
ldns_rr_free(rr);
}
*result_len = pos;
wire2 = LDNS_XMALLOC(uint8_t, *result_len);
if(!wire2) {
return NULL;
}
memcpy(wire2, wire, *result_len);
ldns_write_uint16(wire2 + LDNS_ARCOUNT_OFF, ar_count);
return wire2;
}
static ldns_status
ldns_tsig_mac_new(ldns_rdf **tsig_mac, uint8_t *pkt_wire, size_t pkt_wire_size,
const char *key_data, ldns_rdf *key_name_rdf, ldns_rdf *fudge_rdf,
ldns_rdf *algorithm_rdf, ldns_rdf *time_signed_rdf, ldns_rdf *error_rdf,
ldns_rdf *other_data_rdf, ldns_rdf *orig_mac_rdf, int tsig_timers_only)
{
ldns_status status;
char *wireformat;
int wiresize;
unsigned char *mac_bytes = NULL;
unsigned char *key_bytes = NULL;
int key_size;
const EVP_MD *digester;
char *algorithm_name = NULL;
unsigned int md_len = EVP_MAX_MD_SIZE;
ldns_rdf *result = NULL;
ldns_buffer *data_buffer = NULL;
ldns_rdf *canonical_key_name_rdf = NULL;
ldns_rdf *canonical_algorithm_rdf = NULL;
if (key_name_rdf == NULL || algorithm_rdf == NULL) {
return LDNS_STATUS_NULL;
}
canonical_key_name_rdf = ldns_rdf_clone(key_name_rdf);
if (canonical_key_name_rdf == NULL) {
return LDNS_STATUS_MEM_ERR;
}
canonical_algorithm_rdf = ldns_rdf_clone(algorithm_rdf);
if (canonical_algorithm_rdf == NULL) {
ldns_rdf_deep_free(canonical_key_name_rdf);
return LDNS_STATUS_MEM_ERR;
}
/*
* prepare the digestable information
*/
data_buffer = ldns_buffer_new(LDNS_MAX_PACKETLEN);
if (!data_buffer) {
status = LDNS_STATUS_MEM_ERR;
goto clean;
}
/* if orig_mac is not NULL, add it too */
if (orig_mac_rdf) {
(void) ldns_rdf2buffer_wire(data_buffer, orig_mac_rdf);
}
ldns_buffer_write(data_buffer, pkt_wire, pkt_wire_size);
if (!tsig_timers_only) {
ldns_dname2canonical(canonical_key_name_rdf);
(void)ldns_rdf2buffer_wire(data_buffer,
canonical_key_name_rdf);
ldns_buffer_write_u16(data_buffer, LDNS_RR_CLASS_ANY);
ldns_buffer_write_u32(data_buffer, 0);
ldns_dname2canonical(canonical_algorithm_rdf);
(void)ldns_rdf2buffer_wire(data_buffer,
canonical_algorithm_rdf);
}
(void)ldns_rdf2buffer_wire(data_buffer, time_signed_rdf);
(void)ldns_rdf2buffer_wire(data_buffer, fudge_rdf);
if (!tsig_timers_only) {
(void)ldns_rdf2buffer_wire(data_buffer, error_rdf);
(void)ldns_rdf2buffer_wire(data_buffer, other_data_rdf);
}
wireformat = (char *) data_buffer->_data;
wiresize = (int) ldns_buffer_position(data_buffer);
algorithm_name = ldns_rdf2str(algorithm_rdf);
if(!algorithm_name) {
status = LDNS_STATUS_MEM_ERR;
goto clean;
}
/* prepare the key */
key_bytes = LDNS_XMALLOC(unsigned char,
ldns_b64_pton_calculate_size(strlen(key_data)));
if(!key_bytes) {
status = LDNS_STATUS_MEM_ERR;
goto clean;
}
key_size = ldns_b64_pton(key_data, key_bytes,
ldns_b64_pton_calculate_size(strlen(key_data)));
if (key_size < 0) {
status = LDNS_STATUS_INVALID_B64;
goto clean;
}
/* hmac it */
/* 2 spare bytes for the length */
mac_bytes = LDNS_XMALLOC(unsigned char, md_len+2);
if(!mac_bytes) {
status = LDNS_STATUS_MEM_ERR;
goto clean;
}
memset(mac_bytes, 0, md_len+2);
digester = ldns_digest_function(algorithm_name);
if (digester) {
(void) HMAC(digester, key_bytes, key_size, (void *)wireformat,
(size_t) wiresize, mac_bytes + 2, &md_len);
ldns_write_uint16(mac_bytes, md_len);
result = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_INT16_DATA, md_len + 2,
mac_bytes);
} else {
status = LDNS_STATUS_CRYPTO_UNKNOWN_ALGO;
goto clean;
}
*tsig_mac = result;
status = LDNS_STATUS_OK;
clean:
LDNS_FREE(mac_bytes);
LDNS_FREE(key_bytes);
LDNS_FREE(algorithm_name);
ldns_buffer_free(data_buffer);
ldns_rdf_deep_free(canonical_algorithm_rdf);
ldns_rdf_deep_free(canonical_key_name_rdf);
return status;
}
ldns_status
ldns_pkt2buffer_wire(ldns_buffer *buffer, const ldns_pkt *packet)
{
ldns_rr_list *rr_list;
uint16_t i;
/* edns tmp vars */
ldns_rr *edns_rr;
uint8_t edata[4];
(void) ldns_hdr2buffer_wire(buffer, packet);
rr_list = ldns_pkt_question(packet);
if (rr_list) {
for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
(void) ldns_rr2buffer_wire(buffer,
ldns_rr_list_rr(rr_list, i), LDNS_SECTION_QUESTION);
}
}
rr_list = ldns_pkt_answer(packet);
if (rr_list) {
for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
(void) ldns_rr2buffer_wire(buffer,
ldns_rr_list_rr(rr_list, i), LDNS_SECTION_ANSWER);
}
}
rr_list = ldns_pkt_authority(packet);
if (rr_list) {
for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
(void) ldns_rr2buffer_wire(buffer,
ldns_rr_list_rr(rr_list, i), LDNS_SECTION_AUTHORITY);
}
}
rr_list = ldns_pkt_additional(packet);
if (rr_list) {
for (i = 0; i < ldns_rr_list_rr_count(rr_list); i++) {
(void) ldns_rr2buffer_wire(buffer,
ldns_rr_list_rr(rr_list, i), LDNS_SECTION_ADDITIONAL);
}
}
/* add EDNS to additional if it is needed */
if (ldns_pkt_edns(packet)) {
edns_rr = ldns_rr_new();
ldns_rr_set_owner(edns_rr,
ldns_rdf_new_frm_str(LDNS_RDF_TYPE_DNAME, "."));
ldns_rr_set_type(edns_rr, LDNS_RR_TYPE_OPT);
ldns_rr_set_class(edns_rr, ldns_pkt_edns_udp_size(packet));
edata[0] = ldns_pkt_edns_extended_rcode(packet);
edata[1] = ldns_pkt_edns_version(packet);
ldns_write_uint16(&edata[2], ldns_pkt_edns_z(packet));
ldns_rr_set_ttl(edns_rr, ldns_read_uint32(edata));
(void)ldns_rr2buffer_wire(buffer, edns_rr, LDNS_SECTION_ADDITIONAL);
ldns_rr_free(edns_rr);
}
/* add TSIG to additional if it is there */
if (ldns_pkt_tsig(packet)) {
(void) ldns_rr2buffer_wire(buffer,
ldns_pkt_tsig(packet), LDNS_SECTION_ADDITIONAL);
}
return LDNS_STATUS_OK;
}
/** synthesize DNAME+CNAME response from cached DNAME item */
static struct dns_msg*
synth_dname_msg(struct ub_packed_rrset_key* rrset, struct regional* region,
uint32_t now, struct query_info* q)
{
struct dns_msg* msg;
struct ub_packed_rrset_key* ck;
struct packed_rrset_data* newd, *d = (struct packed_rrset_data*)
rrset->entry.data;
uint8_t* newname, *dtarg = NULL;
size_t newlen, dtarglen;
if(now > d->ttl)
return NULL;
/* only allow validated (with DNSSEC) DNAMEs used from cache
* for insecure DNAMEs, query again. */
if(d->security != sec_status_secure)
return NULL;
msg = gen_dns_msg(region, q, 2); /* DNAME + CNAME RRset */
if(!msg)
return NULL;
msg->rep->flags = BIT_QR; /* reply, no AA, no error */
msg->rep->authoritative = 0; /* reply stored in cache can't be authoritative */
msg->rep->qdcount = 1;
msg->rep->ttl = d->ttl - now;
msg->rep->prefetch_ttl = PREFETCH_TTL_CALC(msg->rep->ttl);
msg->rep->security = sec_status_unchecked;
msg->rep->an_numrrsets = 1;
msg->rep->ns_numrrsets = 0;
msg->rep->ar_numrrsets = 0;
msg->rep->rrset_count = 1;
msg->rep->rrsets[0] = packed_rrset_copy_region(rrset, region, now);
if(!msg->rep->rrsets[0]) /* copy DNAME */
return NULL;
/* synth CNAME rrset */
get_cname_target(rrset, &dtarg, &dtarglen);
if(!dtarg)
return NULL;
newlen = q->qname_len + dtarglen - rrset->rk.dname_len;
if(newlen > LDNS_MAX_DOMAINLEN) {
msg->rep->flags |= LDNS_RCODE_YXDOMAIN;
return msg;
}
newname = (uint8_t*)regional_alloc(region, newlen);
if(!newname)
return NULL;
/* new name is concatenation of qname front (without DNAME owner)
* and DNAME target name */
memcpy(newname, q->qname, q->qname_len-rrset->rk.dname_len);
memmove(newname+(q->qname_len-rrset->rk.dname_len), dtarg, dtarglen);
/* create rest of CNAME rrset */
ck = (struct ub_packed_rrset_key*)regional_alloc(region,
sizeof(struct ub_packed_rrset_key));
if(!ck)
return NULL;
memset(&ck->entry, 0, sizeof(ck->entry));
msg->rep->rrsets[1] = ck;
ck->entry.key = ck;
ck->rk.type = htons(LDNS_RR_TYPE_CNAME);
ck->rk.rrset_class = rrset->rk.rrset_class;
ck->rk.flags = 0;
ck->rk.dname = regional_alloc_init(region, q->qname, q->qname_len);
if(!ck->rk.dname)
return NULL;
ck->rk.dname_len = q->qname_len;
ck->entry.hash = rrset_key_hash(&ck->rk);
newd = (struct packed_rrset_data*)regional_alloc_zero(region,
sizeof(struct packed_rrset_data) + sizeof(size_t) +
sizeof(uint8_t*) + sizeof(uint32_t) + sizeof(uint16_t)
+ newlen);
if(!newd)
return NULL;
ck->entry.data = newd;
newd->ttl = 0; /* 0 for synthesized CNAME TTL */
newd->count = 1;
newd->rrsig_count = 0;
newd->trust = rrset_trust_ans_noAA;
newd->rr_len = (size_t*)((uint8_t*)newd +
sizeof(struct packed_rrset_data));
newd->rr_len[0] = newlen + sizeof(uint16_t);
packed_rrset_ptr_fixup(newd);
newd->rr_ttl[0] = newd->ttl;
msg->rep->ttl = newd->ttl;
msg->rep->prefetch_ttl = PREFETCH_TTL_CALC(newd->ttl);
ldns_write_uint16(newd->rr_data[0], newlen);
memmove(newd->rr_data[0] + sizeof(uint16_t), newname, newlen);
msg->rep->an_numrrsets ++;
msg->rep->rrset_count ++;
return msg;
}
/*
* Parses data buffer to a query, finds the correct answer
* and calls the given function for every packet to send.
*/
void
handle_query(uint8_t* inbuf, ssize_t inlen, struct entry* entries, int* count,
enum transport_type transport, void (*sendfunc)(uint8_t*, size_t, void*),
void* userdata, FILE* verbose_out)
{
ldns_status status;
ldns_pkt *query_pkt = NULL;
ldns_pkt *answer_pkt = NULL;
struct reply_packet *p;
ldns_rr *query_rr = NULL;
uint8_t *outbuf = NULL;
size_t answer_size = 0;
struct entry* entry = NULL;
ldns_rdf *stop_command = ldns_dname_new_frm_str("server.stop.");
status = ldns_wire2pkt(&query_pkt, inbuf, (size_t)inlen);
if (status != LDNS_STATUS_OK) {
verbose(1, "Got bad packet: %s\n", ldns_get_errorstr_by_id(status));
ldns_rdf_free(stop_command);
return;
}
query_rr = ldns_rr_list_rr(ldns_pkt_question(query_pkt), 0);
verbose(1, "query %d: id %d: %s %d bytes: ", ++(*count), (int)ldns_pkt_id(query_pkt),
(transport==transport_tcp)?"TCP":"UDP", (int)inlen);
if(verbose_out) ldns_rr_print(verbose_out, query_rr);
if(verbose_out) ldns_pkt_print(verbose_out, query_pkt);
if (ldns_rr_get_type(query_rr) == LDNS_RR_TYPE_TXT &&
ldns_rr_get_class(query_rr) == LDNS_RR_CLASS_CH &&
ldns_dname_compare(ldns_rr_owner(query_rr), stop_command) == 0) {
exit(0);
}
/* fill up answer packet */
entry = find_match(entries, query_pkt, transport);
if(!entry || !entry->reply_list) {
verbose(1, "no answer packet for this query, no reply.\n");
ldns_pkt_free(query_pkt);
ldns_rdf_free(stop_command);
return;
}
for(p = entry->reply_list; p; p = p->next)
{
verbose(3, "Answer pkt:\n");
if (p->reply_from_hex) {
/* try to parse the hex packet, if it can be
* parsed, we can use adjust rules. if not,
* send packet literally */
status = ldns_buffer2pkt_wire(&answer_pkt, p->reply_from_hex);
if (status == LDNS_STATUS_OK) {
adjust_packet(entry, answer_pkt, query_pkt);
if(verbose_out) ldns_pkt_print(verbose_out, answer_pkt);
status = ldns_pkt2wire(&outbuf, answer_pkt, &answer_size);
verbose(2, "Answer packet size: %u bytes.\n", (unsigned int)answer_size);
if (status != LDNS_STATUS_OK) {
verbose(1, "Error creating answer: %s\n", ldns_get_errorstr_by_id(status));
ldns_pkt_free(query_pkt);
ldns_rdf_free(stop_command);
return;
}
ldns_pkt_free(answer_pkt);
answer_pkt = NULL;
} else {
verbose(3, "Could not parse hex data (%s), sending hex data directly.\n", ldns_get_errorstr_by_id(status));
/* still try to adjust ID */
answer_size = ldns_buffer_capacity(p->reply_from_hex);
outbuf = LDNS_XMALLOC(uint8_t, answer_size);
memcpy(outbuf, ldns_buffer_export(p->reply_from_hex), answer_size);
if(entry->copy_id) {
ldns_write_uint16(outbuf,
ldns_pkt_id(query_pkt));
}
}
} else {
answer_pkt = ldns_pkt_clone(p->reply);
adjust_packet(entry, answer_pkt, query_pkt);
if(verbose_out) ldns_pkt_print(verbose_out, answer_pkt);
status = ldns_pkt2wire(&outbuf, answer_pkt, &answer_size);
verbose(1, "Answer packet size: %u bytes.\n", (unsigned int)answer_size);
if (status != LDNS_STATUS_OK) {
verbose(1, "Error creating answer: %s\n", ldns_get_errorstr_by_id(status));
ldns_pkt_free(query_pkt);
ldns_rdf_free(stop_command);
return;
}
ldns_pkt_free(answer_pkt);
answer_pkt = NULL;
}
if(p->packet_sleep) {
verbose(3, "sleeping for next packet %d secs\n",
p->packet_sleep);
#ifdef HAVE_SLEEP
sleep(p->packet_sleep);
#else
Sleep(p->packet_sleep * 1000);
#endif
verbose(3, "wakeup for next packet "
"(slept %d secs)\n", p->packet_sleep);
}
sendfunc(outbuf, answer_size, userdata);
LDNS_FREE(outbuf);
outbuf = NULL;
answer_size = 0;
}
ldns_pkt_free(query_pkt);
ldns_rdf_free(stop_command);
}
