/* This program is based on (IIRC)
* getdns/spec/example/example-simple-answers.c.
*
* Resolve DNS name argv[1] of type argv[2] using libgetdns and write
* the resulting RRs to two files, in DNS binary wire format:
*
* - binout: /just_address_answers/0/address_data and
* /just_address_answers/1/address_data
*
* - treeout: output from getdns_rr_dict2wire for all RR's in the
* answer section
*
* Based on getdns/spec/example/example-simple-answers.c.
*/
#include <assert.h>
#include <inttypes.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <getdns/getdns.h>
#include <getdns/getdns_ext_libevent.h>
#include <event2/event.h>
#include "common.h"
/* Set up the callback function, which will also do the processing of the results */
void callback(getdns_context *context,
getdns_callback_type_t callback_type,
getdns_dict *response,
void *userarg,
getdns_transaction_t transaction_id)
{
getdns_return_t r; /* Holder for all function returns */
uint32_t status;
getdns_bindata *address_data;
char *first = NULL, *second = NULL;
FILE *binoutfp = NULL, *treeoutfp = NULL;
(void) context; /* unused parameter */
binoutfp = fopen("binout", "w");
assert(binoutfp != NULL);
treeoutfp = fopen("treeout", "w");
assert(treeoutfp != NULL);
printf( "Callback for query \"%s\" with request ID %"PRIu64".\n"
, (char *)userarg, transaction_id );
switch(callback_type) {
case GETDNS_CALLBACK_CANCEL:
printf("Transaction with ID %"PRIu64" was cancelled.\n", transaction_id);
return;
case GETDNS_CALLBACK_TIMEOUT:
printf("Transaction with ID %"PRIu64" timed out.\n", transaction_id);
return;
case GETDNS_CALLBACK_ERROR:
printf("An error occurred for transaction ID %"PRIu64".\n", transaction_id);
return;
default: break;
}
assert( callback_type == GETDNS_CALLBACK_COMPLETE );
if ((r = getdns_dict_get_int(response, "status", &status)))
fprintf(stderr, "Could not get \"status\" from reponse");
else if (status != GETDNS_RESPSTATUS_GOOD)
fprintf(stderr, "The search had no results, and a return value of %"PRIu32".\n", status);
static char *TREES[] = {"replies_tree", "validation_chain"};
static const int TREES_LEN = 2;
for (int i = 0; i < TREES_LEN; i++) {
if (dump_tree(treeoutfp, response, TREES[i], "answer"))
fprintf(stderr, "Could not dump %s to file\n", TREES[i]);
else if ((r = getdns_dict_get_bindata(response, "/just_address_answers/0/address_data", &address_data)))
fprintf(stderr, "Could not get first address");
else if (fwrite(address_data->data, 1, address_data->size, binoutfp) !=
address_data->size)
fprintf(stderr, "first fwrite: %s\n", strerror(errno));
else if (!(first = getdns_display_ip_address(address_data)))
fprintf(stderr, "Could not convert first address to string\n");
else if ((r = getdns_dict_get_bindata(response, "/just_address_answers/1/address_data", &address_data)))
fprintf(stderr, "Could not get second address");
else if (fwrite(address_data->data, 1, address_data->size, binoutfp) !=
address_data->size)
fprintf(stderr, "second fwrite: %s\n", strerror(errno));
else if (!(second = getdns_display_ip_address(address_data)))
fprintf(stderr, "Could not convert second address to string\n");
if (first) {
printf("The address is %s\n", first);
free(first);
}
if (second) {
printf("The address is %s\n", second);
free(second);
}
if (r) {
assert( r != GETDNS_RETURN_GOOD );
fprintf(stderr, ": %d\n", r);
}
}
getdns_dict_destroy(response);
if (binoutfp) fclose(binoutfp);
if (treeoutfp) fclose(treeoutfp);
}
static getdns_return_t
send_query(getdns_context *context,
char *query_name,
const uint16_t query_type,
getdns_transaction_t *transaction_id)
{
getdns_return_t r = GETDNS_RETURN_GENERIC_ERROR;
getdns_dict *extensions = getdns_dict_create();
char *userarg = query_name;
assert(extensions != NULL);
r = getdns_dict_set_int(extensions,
"dnssec_return_validation_chain",
GETDNS_EXTENSION_TRUE);
if (r) return r;
#if 0
r = getdns_dict_set_int(extensions,
"dnssec_return_status",
GETDNS_EXTENSION_TRUE);
if (r) return r;
#endif
if (query_type == 0)
r = getdns_address(context, query_name, extensions, userarg,
transaction_id, callback);
else
r = getdns_general(context, query_name, query_type,
extensions, userarg,
transaction_id, callback);
if (r) return r;
return r;
}
#define OWN_ROOT
#ifdef OWN_ROOT
getdns_list *
read_own_rootfile()
{
FILE *fp = fopen("root.txt", "r");
getdns_list *list = NULL;
if (fp && !getdns_fp2rr_list(fp, &list, ".", 0))
return list;
return NULL;
}
#endif
int main(int argc, char *argv[])
{
getdns_return_t r; /* Holder for all function returns */
getdns_context *context = NULL;
struct event_base *event_base = NULL;
char *query_name = "www.example.com";
uint16_t query_type = 0;
getdns_transaction_t transaction_id;
getdns_list *trust_anchors;
getdns_list *root_servers = NULL;
if (argc > 1)
query_name = argv[1];
if (argc > 2)
query_type = (uint16_t) atoi(argv[2]);
if ((r = getdns_context_create(&context, 0)))
fprintf(stderr, "Trying to create the context failed");
#ifdef OWN_ROOT
else if (!(root_servers = read_own_rootfile()))
fprintf(stderr, "Reading root hints file failed.\n");
#endif
else if ((r = getdns_context_set_dns_root_servers(context,
root_servers)))
fprintf(stderr, "Setting root name servers failed.\n");
else if ((r = getdns_context_get_dnssec_trust_anchors(
context, &trust_anchors)) ||
trust_anchors == NULL)
fprintf(stderr, "No trust anchor.\n");
else if (!(event_base = event_base_new()))
fprintf(stderr, "Trying to create the event base failed.\n");
else if ((r = getdns_extension_set_libevent_base(context, event_base)))
fprintf(stderr, "Setting the event base failed");
else if ((r = send_query(context, query_name, query_type,
&transaction_id)))
fprintf(stderr, "Queueing query failed: %d\n", r);
else {
printf("Request with transaction ID %"PRIu64" scheduled.\n",
transaction_id);
if (event_base_dispatch(event_base) < 0)
fprintf(stderr, "Error dispatching events\n");
}
/* Clean up */
if (event_base)
event_base_free(event_base);
if (context)
getdns_context_destroy(context);
/* Assuming we get here, leave gracefully */
exit(EXIT_SUCCESS);
}