static int
print_axfr(FILE *file, const u_char *msg, size_t msglen) {
ns_msg handle;
if (ns_initparse(msg, msglen, &handle) < 0) {
fprintf(file, ";; ns_initparse: %s\n", strerror(errno));
return (ns_r_formerr);
}
if (ns_msg_getflag(handle, ns_f_rcode) != ns_r_noerror)
return (ns_msg_getflag(handle, ns_f_rcode));
/*
* We are looking for info from answer resource records.
* If there aren't any, return with an error. We assume
* there aren't any question records.
*/
if (ns_msg_count(handle, ns_s_an) == 0)
return (NO_INFO);
#ifdef PROTOCOLDEBUG
printf(";;; (message of %d octets has %d answers)\n",
msglen, ns_msg_count(handle, ns_s_an));
#endif
for (;;) {
static char origin[NS_MAXDNAME], name_ctx[NS_MAXDNAME];
const char *name;
char buf[2048]; /* XXX need to malloc/realloc. */
ns_rr rr;
if (ns_parserr(&handle, ns_s_an, -1, &rr)) {
if (errno != ENODEV) {
fprintf(file, ";; ns_parserr: %s\n",
strerror(errno));
return (FORMERR);
}
break;
}
name = ns_rr_name(rr);
if (origin[0] == '\0' && name[0] != '\0') {
if (strcmp(name, ".") != 0)
strcpy(origin, name);
fprintf(file, "$ORIGIN %s.\n", origin);
if (strcmp(name, ".") == 0)
strcpy(origin, name);
if (res.pfcode & RES_PRF_TRUNC)
strcpy(name_ctx, "@");
}
if (ns_sprintrr(&handle, &rr,
(res.pfcode & RES_PRF_TRUNC) ? name_ctx : NULL,
(res.pfcode & RES_PRF_TRUNC) ? origin : NULL,
buf, sizeof buf) < 0) {
fprintf(file, ";; ns_sprintrr: %s\n", strerror(errno));
return (FORMERR);
}
strcpy(name_ctx, name);
fputs(buf, file);
fputc('\n', file);
}
return (SUCCESS);
}
static void
do_section(ns_msg *handle, ns_sect section, int pflag, FILE *file) {
int n, sflag, rrnum;
ns_opcode opcode;
ns_rr rr;
/*
* Print answer records.
*/
sflag = (int)(_res.pfcode & pflag);
if (_res.pfcode && !sflag)
return;
opcode = ns_msg_getflag(*handle, ns_f_opcode);
rrnum = 0;
for (;;) {
if (ns_parserr(handle, section, rrnum, &rr)) {
if (errno != ENODEV)
fprintf(file, ";; ns_parserr: %s\n",
strerror(errno));
else if (rrnum > 0 && sflag != 0 &&
(_res.pfcode & RES_PRF_HEAD1))
putc('\n', file);
return;
}
if (rrnum == 0 && sflag != 0 && (_res.pfcode & RES_PRF_HEAD1))
fprintf(file, ";; %s SECTION:\n",
p_section(section, opcode));
if (section == ns_s_qd)
fprintf(file, ";;\t%s, type = %s, class = %s\n",
ns_rr_name(rr),
p_type(ns_rr_type(rr)),
p_class(ns_rr_class(rr)));
else {
char *buf;
buf = (char*)malloc(2024);
if (buf) {
n = ns_sprintrr(handle, &rr, NULL, NULL,
buf, sizeof buf);
if (n < 0) {
fprintf(file, ";; ns_sprintrr: %s\n",
strerror(errno));
free(buf);
return;
}
fputs(buf, file);
fputc('\n', file);
free(buf);
}
}
rrnum++;
}
}
void query_as(char *arg, char *namelisten_addr, char *buf, int buflen) {
u_char nsbuf[4096];
ns_msg msg;
ns_rr rr;
int len;
// Set namelisten_addr
res_init();
struct in_addr listen_addr_in_addr;
if (inet_pton(AF_INET, namelisten_addr, &listen_addr_in_addr) > 0) {
_res.nscount = 1;
_res.nsaddr_list[0].sin_addr = listen_addr_in_addr;
}
len = res_query(arg, ns_c_any, ns_t_txt, nsbuf, sizeof(nsbuf));
ns_initparse(nsbuf, len, &msg);
ns_parserr(&msg, ns_s_an, 0, &rr);
ns_sprintrr(&msg, &rr, NULL, NULL, buf, buflen);
}
}
if (rrnum == 0 && sflag != 0 && (statp->pfcode & RES_PRF_HEAD1))
fprintf(file, ";; %s SECTION:\n",
p_section(section, opcode));
if (section == ns_s_qd)
fprintf(file, ";;\t%s, type = %s, class = %s\n",
ns_rr_name(rr),
p_type(ns_rr_type(rr)),
p_class(ns_rr_class(rr)));
else if (section == ns_s_ar && ns_rr_type(rr) == ns_t_opt) {
u_int32_t ttl = ns_rr_ttl(rr);
fprintf(file,
"; EDNS: version: %u, udp=%u, flags=%04x\n",
(ttl>>16)&0xff, ns_rr_class(rr), ttl&0xffff);
} else {
n = ns_sprintrr(handle, &rr, NULL, NULL,
buf, (u_int)buflen);
if (n < 0) {
if (errno == ENOSPC) {
free(buf);
buf = NULL;
if (buflen < 131072)
buf = malloc((size_t)(buflen += 1024));
if (buf == NULL) {
fprintf(file,
";; memory allocation failure\n");
return;
}
continue;
}
fprintf(file, ";; ns_sprintrr: %s\n",
strerror(errno));
/*
Simple interface to provide DNS MX record resolution.
@param Pointer to the c string hostname you would like resolved to an MX record.
@param Pointer to the struct you would like the results written out to.
@return Return is of type int and is just the mx family type in the variable ohana. Ohana is hawaiian for family.
*/
int resolve_server(char * hostname, struct sockaddr_storage * result)
{
pthread_mutex_lock(&dns_lock);
res_init();
int error = 0;
int ohana = 0;
ns_msg msg;
ns_rr rr;
struct addrinfo * addr_res;
int res_length = 0;
unsigned char dns_answer[4096] = {0};
char display_buffer[4096] = {0};
//ldns variables
ldns_resolver *ldns_resolv;
ldns_rdf *ldns_domain;
ldns_pkt *ldns_packet;
ldns_rr_list *ldns_mx_records;
ldns_status s;
//Setup ldns to query for the mx record
s = ldns_resolver_new_frm_file(&ldns_resolv, NULL);
ldns_domain = ldns_dname_new_frm_str(hostname);
//Use ldns to query
ldns_packet = ldns_resolver_query(ldns_resolv, ldns_domain, LDNS_RR_TYPE_MX, LDNS_RR_CLASS_IN, LDNS_RD);
//parse ldns query results
ldns_mx_records = ldns_pkt_rr_list_by_type(ldns_packet, LDNS_RR_TYPE_MX, LDNS_SECTION_ANSWER);
//Sort and print mx records
ldns_rr_list_sort(ldns_mx_records);
ldns_rr_list_print(stdout, ldns_mx_records);
for (int i = 0; i < ldns_mx_records->_rr_count; i++)
{
printf("^_^ i= %d\n", i);
printf(">_> %s",ldns_rr2str(ldns_rr_list_rr(ldns_mx_records, i)));
printf(">.> %s\n", last_str_split(ldns_rr2str(ldns_rr_list_rr(ldns_mx_records, i)), " "));
}
/////////////////Old code below/////////////////////
res_length = res_query(hostname, C_IN, T_MX, dns_answer, sizeof(dns_answer));
if (ns_initparse(dns_answer, res_length, &msg)<0)
{
printf("hostname = %s\n", hostname);
printf("res_length = %d\n", res_length);
perror("DNS has gone wrong!");
print_to_log("DNS resource query has failed", LOG_ERR);
}
else
{
res_length = ns_msg_count(msg, ns_s_an);
for (int i = 0; i < res_length; i++)
{
//printf("DNS loop level = %d\n", i);
ns_parserr(&msg, ns_s_an, i, &rr);
ns_sprintrr(&msg, &rr, NULL, NULL, display_buffer, sizeof(display_buffer));
if (ns_rr_type(rr) == ns_t_mx)
{
//String parsing solution for rr. Requires creation of display_buffer above
error = getaddrinfo(last_str_split(display_buffer, " "), NULL, NULL, &addr_res);
if (error != 0)
{
printf("error = %d\n", error);
printf("display_buffer = %s\n", display_buffer);
printf("last_str_split = %s\n", last_str_split(display_buffer, " "));
perror("getaddrinfo");
}
if (addr_res->ai_family==AF_INET)
{
//printf("IPv4 mode is go\n");
struct sockaddr_in* temp_addr = (struct sockaddr_in*)addr_res->ai_addr;
memcpy(result, temp_addr, sizeof(*temp_addr));
//printf("ai_addr hostname -> %s\n", inet_ntoa(temp_addr->sin_addr));
ohana = addr_res->ai_family;
}
else if (addr_res->ai_family==AF_INET6)
{
//printf("v6 mode engaged\n");
struct sockaddr_in6 * temp_addr = (struct sockaddr_in6 *) addr_res->ai_addr;
memcpy(result, temp_addr, sizeof(*temp_addr));
ohana = addr_res->ai_family;
}
}
freeaddrinfo(addr_res);
}
}
pthread_mutex_unlock(&dns_lock);
return ohana;
}
static void
do_section (int pfcode, ns_msg *handle, ns_sect section, int pflag, FILE *file)
{
int n, sflag, rrnum;
static int buflen = 2048;
char *buf;
ns_opcode opcode;
ns_rr rr;
/*
* Print answer records.
*/
sflag = (pfcode & pflag);
if (pfcode && !sflag)
return;
buf = malloc(buflen);
if (buf == NULL) {
fprintf(file, ";; memory allocation failure\n");
return;
}
opcode = (ns_opcode) ns_msg_getflag(*handle, ns_f_opcode);
rrnum = 0;
for (;;) {
if (ns_parserr(handle, section, rrnum, &rr)) {
if (errno != ENODEV)
fprintf(file, ";; ns_parserr: %s\n",
strerror(errno));
else if (rrnum > 0 && sflag != 0 &&
(pfcode & RES_PRF_HEAD1))
putc('\n', file);
goto cleanup;
}
if (rrnum == 0 && sflag != 0 && (pfcode & RES_PRF_HEAD1))
fprintf(file, ";; %s SECTION:\n",
p_section(section, opcode));
if (section == ns_s_qd)
fprintf(file, ";;\t%s, type = %s, class = %s\n",
ns_rr_name(rr),
p_type(ns_rr_type(rr)),
p_class(ns_rr_class(rr)));
else {
n = ns_sprintrr(handle, &rr, NULL, NULL,
buf, buflen);
if (n < 0) {
if (errno == ENOSPC) {
free(buf);
buf = NULL;
if (buflen < 131072)
buf = malloc(buflen += 1024);
if (buf == NULL) {
fprintf(file,
";; memory allocation failure\n");
return;
}
continue;
}
fprintf(file, ";; ns_sprintrr: %s\n",
strerror(errno));
goto cleanup;
}
fputs(buf, file);
fputc('\n', file);
}
rrnum++;
}
cleanup:
free(buf);
}
