int
main(int argc, char **argv)
{
/* arguments */
int port;
const char *zone_file;
/* network */
int sock;
ssize_t nb;
struct sockaddr addr_me;
struct sockaddr addr_him;
socklen_t hislen = (socklen_t) sizeof(addr_him);
uint8_t inbuf[INBUF_SIZE];
uint8_t *outbuf;
/* dns */
ldns_status status;
ldns_pkt *query_pkt;
ldns_pkt *answer_pkt;
size_t answer_size;
ldns_rr *query_rr;
ldns_rr_list *answer_qr;
ldns_rr_list *answer_an;
ldns_rr_list *answer_ns;
ldns_rr_list *answer_ad;
ldns_rdf *origin = NULL;
/* zone */
ldns_zone *zone;
int line_nr;
FILE *zone_fp;
/* use this to listen on specified interfaces later? */
char *my_address = NULL;
if (argc < 5) {
usage(stderr);
exit(EXIT_FAILURE);
} else {
my_address = argv[1];
port = atoi(argv[2]);
if (port < 1) {
usage(stderr);
exit(EXIT_FAILURE);
}
if (ldns_str2rdf_dname(&origin, argv[3]) != LDNS_STATUS_OK) {
fprintf(stderr, "Bad origin, not a correct domain name\n");
usage(stderr);
exit(EXIT_FAILURE);
}
zone_file = argv[4];
}
printf("Reading zone file %s\n", zone_file);
zone_fp = fopen(zone_file, "r");
if (!zone_fp) {
fprintf(stderr, "Unable to open %s: %s\n", zone_file, strerror(errno));
exit(EXIT_FAILURE);
}
line_nr = 0;
status = ldns_zone_new_frm_fp_l(&zone, zone_fp, origin, 0, LDNS_RR_CLASS_IN, &line_nr);
if (status != LDNS_STATUS_OK) {
printf("Zone reader failed, aborting\n");
exit(EXIT_FAILURE);
} else {
printf("Read %u resource records in zone file\n", (unsigned int) ldns_zone_rr_count(zone));
}
fclose(zone_fp);
printf("Listening on port %d\n", port);
sock = socket(AF_INET, SOCK_DGRAM, 0);
if (sock < 0) {
fprintf(stderr, "%s: socket(): %s\n", argv[0], strerror(errno));
exit(1);
}
memset(&addr_me, 0, sizeof(addr_me));
/* bind: try all ports in that range */
if (udp_bind(sock, port, my_address)) {
fprintf(stderr, "%s: cannot bind(): %s\n", argv[0], strerror(errno));
exit(errno);
}
/* Done. Now receive */
while (1) {
nb = recvfrom(sock, (void*)inbuf, INBUF_SIZE, 0,
&addr_him, &hislen);
if (nb < 1) {
fprintf(stderr, "%s: recvfrom(): %s\n",
argv[0], strerror(errno));
exit(1);
}
/*
show(inbuf, nb, nn, hp, sp, ip, bp);
*/
printf("Got query of %u bytes\n", (unsigned int) nb);
status = ldns_wire2pkt(&query_pkt, inbuf, (size_t) nb);
if (status != LDNS_STATUS_OK) {
printf("Got bad packet: %s\n", ldns_get_errorstr_by_id(status));
} else {
ldns_pkt_print(stdout, query_pkt);
}
query_rr = ldns_rr_list_rr(ldns_pkt_question(query_pkt), 0);
printf("QUERY RR: \n");
ldns_rr_print(stdout, query_rr);
answer_qr = ldns_rr_list_new();
ldns_rr_list_push_rr(answer_qr, ldns_rr_clone(query_rr));
answer_an = get_rrset(zone, ldns_rr_owner(query_rr), ldns_rr_get_type(query_rr), ldns_rr_get_class(query_rr));
answer_pkt = ldns_pkt_new();
answer_ns = ldns_rr_list_new();
answer_ad = ldns_rr_list_new();
ldns_pkt_set_qr(answer_pkt, 1);
ldns_pkt_set_aa(answer_pkt, 1);
ldns_pkt_set_id(answer_pkt, ldns_pkt_id(query_pkt));
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_QUESTION, answer_qr);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ANSWER, answer_an);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_AUTHORITY, answer_ns);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ADDITIONAL, answer_ad);
status = ldns_pkt2wire(&outbuf, answer_pkt, &answer_size);
printf("Answer packet size: %u bytes.\n", (unsigned int) answer_size);
if (status != LDNS_STATUS_OK) {
printf("Error creating answer: %s\n", ldns_get_errorstr_by_id(status));
} else {
nb = sendto(sock, (void*)outbuf, answer_size, 0,
&addr_him, hislen);
}
ldns_pkt_free(query_pkt);
ldns_pkt_free(answer_pkt);
LDNS_FREE(outbuf);
ldns_rr_list_free(answer_qr);
ldns_rr_list_free(answer_an);
ldns_rr_list_free(answer_ns);
ldns_rr_list_free(answer_ad);
}
/* No cleanup because of the infinite loop
*
* ldns_rdf_deep_free(origin);
* ldns_zone_deep_free(zone);
* return 0;
*/
}
void zkdns_start(const char* my_address, int port, const char* my_zone)
{
rp_handle = rp_initialize(my_zone);
/* network */
int sock;
ssize_t nb;
struct sockaddr addr_me;
struct sockaddr addr_him;
socklen_t hislen = (socklen_t) sizeof(addr_him);
uint8_t inbuf[INBUF_SIZE];
uint8_t *outbuf;
/* dns */
ldns_status status;
ldns_pkt *query_pkt;
ldns_pkt *answer_pkt;
size_t answer_size;
ldns_rr *query_rr;
ldns_rr_list *answer_qr;
ldns_rr_list *answer_an;
ldns_rr_list *answer_ns;
ldns_rr_list *answer_ad;
ldns_rdf *origin = NULL;
/* zone */
ldns_zone *zone;
int line_nr;
FILE *zone_fp;
if (ldns_str2rdf_dname(&origin, my_zone) != LDNS_STATUS_OK) {
fprintf(stderr, "Bad origin, not a correct domain name\n");
exit(EXIT_FAILURE);
}
printf("Listening on port %d\n", port);
sock = socket(AF_INET, SOCK_DGRAM, 0);
if (sock < 0) {
fprintf(stderr, "socket(): %s\n", strerror(errno));
exit(1);
}
memset(&addr_me, 0, sizeof(addr_me));
/* bind: try all ports in that range */
if (udp_bind(sock, port, my_address)) {
fprintf(stderr, "cannot bind(): %s\n", strerror(errno));
exit(errno);
}
/* Done. Now receive */
while (1) {
nb = recvfrom(sock, (void*)inbuf, INBUF_SIZE, 0,
&addr_him, &hislen);
if (nb < 1) {
fprintf(stderr, "recvfrom(): %s\n",
strerror(errno));
exit(1);
}
/*
show(inbuf, nb, nn, hp, sp, ip, bp);
*/
status = ldns_wire2pkt(&query_pkt, inbuf, (size_t) nb);
if (status != LDNS_STATUS_OK) {
printf("Got bad packet: %s\n", ldns_get_errorstr_by_id(status));
}
query_rr = ldns_rr_list_rr(ldns_pkt_question(query_pkt), 0);
answer_qr = ldns_rr_list_new();
ldns_rr_list_push_rr(answer_qr, ldns_rr_clone(query_rr));
answer_an = get_rrset(zone, ldns_rr_owner(query_rr), ldns_rr_get_type(query_rr), ldns_rr_get_class(query_rr));
answer_pkt = ldns_pkt_new();
answer_ns = ldns_rr_list_new();
answer_ad = ldns_rr_list_new();
ldns_pkt_set_qr(answer_pkt, 1);
ldns_pkt_set_aa(answer_pkt, 1);
ldns_pkt_set_id(answer_pkt, ldns_pkt_id(query_pkt));
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_QUESTION, answer_qr);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ANSWER, answer_an);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_AUTHORITY, answer_ns);
ldns_pkt_push_rr_list(answer_pkt, LDNS_SECTION_ADDITIONAL, answer_ad);
status = ldns_pkt2wire(&outbuf, answer_pkt, &answer_size);
if (status != LDNS_STATUS_OK) {
printf("Error creating answer: %s\n", ldns_get_errorstr_by_id(status));
} else {
nb = sendto(sock, (void*)outbuf, answer_size, 0,
&addr_him, hislen);
}
ldns_pkt_free(query_pkt);
ldns_pkt_free(answer_pkt);
LDNS_FREE(outbuf);
ldns_rr_list_free(answer_qr);
ldns_rr_list_free(answer_an);
ldns_rr_list_free(answer_ns);
ldns_rr_list_free(answer_ad);
}
ldns_rdf_deep_free(origin);
ldns_zone_deep_free(zone);
rp_shutdown(rp_handle);
}
/** parse REPLY line */
static void replyline(char* line, ldns_pkt *reply)
{
char* parse = line;
while(*parse) {
if(isendline(*parse))
return;
/* opcodes */
if(str_keyword(&parse, "QUERY")) {
ldns_pkt_set_opcode(reply, LDNS_PACKET_QUERY);
} else if(str_keyword(&parse, "IQUERY")) {
ldns_pkt_set_opcode(reply, LDNS_PACKET_IQUERY);
} else if(str_keyword(&parse, "STATUS")) {
ldns_pkt_set_opcode(reply, LDNS_PACKET_STATUS);
} else if(str_keyword(&parse, "NOTIFY")) {
ldns_pkt_set_opcode(reply, LDNS_PACKET_NOTIFY);
} else if(str_keyword(&parse, "UPDATE")) {
ldns_pkt_set_opcode(reply, LDNS_PACKET_UPDATE);
/* rcodes */
} else if(str_keyword(&parse, "NOERROR")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NOERROR);
} else if(str_keyword(&parse, "FORMERR")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_FORMERR);
} else if(str_keyword(&parse, "SERVFAIL")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_SERVFAIL);
} else if(str_keyword(&parse, "NXDOMAIN")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NXDOMAIN);
} else if(str_keyword(&parse, "NOTIMPL")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NOTIMPL);
} else if(str_keyword(&parse, "REFUSED")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_REFUSED);
} else if(str_keyword(&parse, "YXDOMAIN")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_YXDOMAIN);
} else if(str_keyword(&parse, "YXRRSET")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_YXRRSET);
} else if(str_keyword(&parse, "NXRRSET")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NXRRSET);
} else if(str_keyword(&parse, "NOTAUTH")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NOTAUTH);
} else if(str_keyword(&parse, "NOTZONE")) {
ldns_pkt_set_rcode(reply, LDNS_RCODE_NOTZONE);
/* flags */
} else if(str_keyword(&parse, "QR")) {
ldns_pkt_set_qr(reply, true);
} else if(str_keyword(&parse, "AA")) {
ldns_pkt_set_aa(reply, true);
} else if(str_keyword(&parse, "TC")) {
ldns_pkt_set_tc(reply, true);
} else if(str_keyword(&parse, "RD")) {
ldns_pkt_set_rd(reply, true);
} else if(str_keyword(&parse, "CD")) {
ldns_pkt_set_cd(reply, true);
} else if(str_keyword(&parse, "RA")) {
ldns_pkt_set_ra(reply, true);
} else if(str_keyword(&parse, "AD")) {
ldns_pkt_set_ad(reply, true);
} else if(str_keyword(&parse, "DO")) {
ldns_pkt_set_edns_udp_size(reply, 4096);
ldns_pkt_set_edns_do(reply, true);
} else {
error("could not parse REPLY: '%s'", parse);
}
}
}