#include "gnunet_crypto_lib.h"
#include "gnunet_signatures.h"
-
/**
* The UDP-Socket through which DNS-Resolves will be sent if they are not to be
* sent through gnunet. The port of this socket will not be hijacked.
* Hijack all outgoing DNS-Traffic but for traffic leaving "our" port.
*/
static void
-hijack(unsigned short port) {
+hijack(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) {
char port_s[6];
- GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", port);
- snprintf(port_s, 6, "%d", port);
- GNUNET_OS_start_process(NULL,
- NULL,
- "gnunet-helper-hijack-dns",
- "gnunet-hijack-dns",
- port_s,
- NULL);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", dnsoutport);
+ snprintf(port_s, 6, "%d", dnsoutport);
+ GNUNET_OS_process_close (GNUNET_OS_start_process(NULL,
+ NULL,
+ "gnunet-helper-hijack-dns",
+ "gnunet-hijack-dns",
+ port_s,
+ NULL));
}
/**
return len;
}
+static void
+send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
+ struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
+
+ unsigned short id = pdns->s.id;
+
+ if (query_states[id].valid != GNUNET_YES) return;
+ query_states[id].valid = GNUNET_NO;
+
+ GNUNET_assert(query_states[id].namelen == 74);
+
+ size_t len = sizeof(struct answer_packet) - 1 \
+ + sizeof(struct dns_static) \
+ + 74 /* this is the length of a reverse ipv6-lookup */ \
+ + sizeof(struct dns_query_line) \
+ + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
+ + sizeof(struct dns_record_line) - 1 \
+ - 2 /* We do not know the lenght of the answer yet*/ \
+ - 2 /* No idea why... */ ;
+
+ struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*));
+ memset(answer, 0, len + 2*sizeof(struct answer_packet_list*));
+
+ answer->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS);
+ answer->pkt.hdr.size = htons(len);
+ answer->pkt.subtype = GNUNET_DNS_ANSWER_TYPE_REV;
+
+ answer->pkt.from = query_states[id].remote_ip;
+
+ answer->pkt.to = query_states[id].local_ip;
+ answer->pkt.dst_port = query_states[id].local_port;
+
+ struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data;
+
+ dpkt->s.id = id;
+ dpkt->s.aa = 1;
+ dpkt->s.qr = 1;
+ dpkt->s.ra = 1;
+ dpkt->s.qdcount = htons(1);
+ dpkt->s.ancount = htons(1);
+
+ memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
+ GNUNET_free(query_states[id].name);
+
+ struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
+ dque->type = htons(12); /* PTR */
+ dque->class = htons(1); /* IN */
+
+ char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
+ memcpy(anname, (char[]){0xc0, 0x0c}, 2);
+
+ struct dns_record_line *drec_data = (struct dns_record_line*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line)+2);
+ drec_data->type = htons(12); /* AAAA */
+ drec_data->class = htons(1); /* IN */
+ drec_data->ttl = htonl(3600); /* FIXME: read from block */
+
+ /* Calculate at which offset in the packet the length of the name and the
+ * name, it is filled in by the daemon-vpn */
+ answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data_len)-(unsigned long)(&answer->pkt)));
+
+ GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
+
+ GNUNET_SERVER_notify_transmit_ready(query_states[id].client,
+ len,
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ &send_answer,
+ query_states[id].client);
+
+ /*
+ * build
+ * complete dns-packet with empty name in the answer
+ * provide offsett of the name
+ */
+}
+
/**
* Receive a block from the dht.
*/
memcpy(dpkt->data, query_states[id].name, query_states[id].namelen);
GNUNET_free(query_states[id].name);
-
struct dns_query_line* dque = (struct dns_query_line*)(dpkt->data+(query_states[id].namelen));
dque->type = htons(28); /* AAAA */
dque->class = htons(1); /* IN */
struct GNUNET_SERVER_Client *client,
const struct GNUNET_MessageHeader *message) {
unhijack(dnsoutport);
- hijack(dnsoutport);
+ GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
+
+ GNUNET_SERVER_receive_done(client, GNUNET_OK);
}
/**
query_states[dns->s.id].name = GNUNET_malloc(query_states[dns->s.id].namelen);
memcpy(query_states[dns->s.id].name, dns->data, query_states[dns->s.id].namelen);
+ /* The query is for a .gnunet-address */
if (pdns->queries[0]->namelen > 9 &&
0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 9), ".gnunet.", 9))
{
receive_dht,
cls);
+ goto outfree;
+ }
+
+ /* The query is for a PTR of a previosly resolved virtual IP */
+ if (htons(pdns->queries[0]->qtype) == 12 &&
+ pdns->queries[0]->namelen > 19 &&
+ 0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - 19), ".4.3.2.1.ip6.arpa.", 19))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
+
+ GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
+
goto out;
}
(struct sockaddr*) &dest,
sizeof dest);
-out:
+outfree:
free_parsed_dns_packet(pdns);
pdns = NULL;
+out:
GNUNET_SERVER_receive_done(client, GNUNET_OK);
}
/**
* @param cls closure
+ * @param sched scheduler to use
* @param server the initialized server
* @param cfg configuration to use
*/
dnsoutport = htons(addr.sin_port);
- hijack(htons(addr.sin_port));
-
GNUNET_SCHEDULER_add_now (publish_name, NULL);
GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL, dnsout, &read_response, NULL);