/**
* @file vpn/gnunet-service-dns.c
- * @author Philipp Tรถlke
+ * @author Philipp Toelke
*/
#include "platform.h"
#include "gnunet_getopt_lib.h"
#include "gnunet_service_lib.h"
#include "gnunet_network_lib.h"
#include "gnunet_os_lib.h"
+#include "gnunet-service-dns-p.h"
+#include "gnunet_protocols.h"
+#include "gnunet_applications.h"
+#include "gnunet-vpn-packet.h"
+#include "gnunet_container_lib.h"
+#include "gnunet-dns-parser.h"
+#include "gnunet_dht_service.h"
+#include "gnunet_block_lib.h"
+#include "block_dns.h"
+#include "gnunet_crypto_lib.h"
+#include "gnunet_mesh_service.h"
+#include "gnunet_signatures.h"
-struct dns_cls {
- struct GNUNET_SCHEDULER_Handle *sched;
+struct GNUNET_MESH_Handle *mesh_handle;
- struct GNUNET_NETWORK_Handle *dnsout;
+/**
+ * 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.
+ */
+static struct GNUNET_NETWORK_Handle *dnsout;
+
+/**
+ * The port bound to the socket dnsout
+ */
+static unsigned short dnsoutport;
+
+/**
+ * A handle to the DHT-Service
+ */
+static struct GNUNET_DHT_Handle *dht;
+
+/**
+ * The configuration to use
+ */
+static const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+/**
+ * The handle to the service-configuration
+ */
+static struct GNUNET_CONFIGURATION_Handle *servicecfg;
+
+/**
+ * A list of DNS-Responses that have to be sent to the requesting client
+ */
+static struct answer_packet_list *head;
+
+/**
+ * The tail of the list of DNS-responses
+ */
+static struct answer_packet_list *tail;
+
+/**
+ * A structure containing a mapping from network-byte-ordered DNS-id (16 bit) to
+ * some information needed to handle this query
+ *
+ * It currently allocates at least
+ * (1 + machine-width + 32 + 32 + 16 + machine-width + 8) * 65536 bit
+ * = 1.7 MiB on 64 bit.
+ * = 1.2 MiB on 32 bit.
+ */
+static struct {
+ unsigned valid:1;
+ struct GNUNET_SERVER_Client* client;
+ uint32_t local_ip;
+ uint32_t remote_ip;
+ uint16_t local_port;
+ char* name;
+ uint8_t namelen;
+} query_states[UINT16_MAX];
+
+/**
+ * A struct used to give more than one value as
+ * closure to receive_dht
+ */
+struct receive_dht_cls {
+ uint16_t id;
+ struct GNUNET_DHT_GetHandle* handle;
+};
+
+/**
+ * Hijack all outgoing DNS-Traffic but for traffic leaving "our" port.
+ */
+static void
+hijack (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ char port_s[6];
+ char *virt_dns;
+ struct GNUNET_OS_Process *proc;
- unsigned short dnsoutport;
+ if (GNUNET_SYSERR ==
+ GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
+ &virt_dns))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "No entry 'VIRTDNS' in configuration!\n");
+ exit (1);
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hijacking, port is %d\n", dnsoutport);
+ snprintf (port_s, 6, "%d", dnsoutport);
+ if (NULL != (proc = GNUNET_OS_start_process (NULL,
+ NULL,
+ "gnunet-helper-hijack-dns",
+ "gnunet-hijack-dns",
+ port_s, virt_dns, NULL)))
+ GNUNET_OS_process_close (proc);
+ GNUNET_free (virt_dns);
+}
+
+/**
+ * Delete the hijacking-routes
+ */
+static void
+unhijack (unsigned short port)
+{
+ char port_s[6];
+ char *virt_dns;
+ struct GNUNET_OS_Process *proc;
+
+ if (GNUNET_SYSERR ==
+ GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
+ &virt_dns))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "No entry 'VIRTDNS' in configuration!\n");
+ exit (1);
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port);
+ snprintf (port_s, 6, "%d", port);
+ if (NULL != (proc = GNUNET_OS_start_process (NULL,
+ NULL,
+ "gnunet-helper-hijack-dns",
+ "gnunet-hijack-dns",
+ "-d", port_s, virt_dns, NULL)))
+ GNUNET_OS_process_close (proc);
+ GNUNET_free (virt_dns);
+}
+
+/**
+ * Send the DNS-Response to the client. Gets called via the notify_transmit_ready-
+ * system.
+ */
+static size_t
+send_answer(void* cls, size_t size, void* buf) {
+ struct answer_packet_list* query = head;
+ size_t len = ntohs(query->pkt.hdr.size);
+
+ GNUNET_assert(len <= size);
+
+ memcpy(buf, &query->pkt.hdr, len);
+
+ GNUNET_CONTAINER_DLL_remove (head, tail, query);
+
+ GNUNET_free(query);
+
+ /* When more data is to be sent, reschedule */
+ if (head != NULL)
+ GNUNET_SERVER_notify_transmit_ready(cls,
+ ntohs(head->pkt.hdr.size),
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ &send_answer,
+ cls);
+
+ return len;
+}
+
+struct tunnel_cls {
+ struct GNUNET_MESH_Tunnel *tunnel;
+ struct GNUNET_MessageHeader hdr;
+ struct dns_pkt dns;
};
-void hijack(unsigned short port) {
- char port_s[5];
+struct tunnel_cls *remote_pending[UINT16_MAX];
+
+
+static size_t
+mesh_send (void *cls, size_t size, void *buf)
+{
+ struct tunnel_cls *cls_ = (struct tunnel_cls *) cls;
+
+ GNUNET_assert(cls_->hdr.size <= size);
+
+ size = cls_->hdr.size;
+ cls_->hdr.size = htons(cls_->hdr.size);
+
+ memcpy(buf, &cls_->hdr, size);
+ return size;
+}
+
+
+void mesh_connect (void* cls, const struct GNUNET_PeerIdentity* peer, const struct GNUNET_TRANSPORT_ATS_Information *atsi) {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connected to peer %x\n", *((unsigned long*)peer));
+ struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
+
+ GNUNET_MESH_notify_transmit_ready(cls_->tunnel,
+ GNUNET_YES,
+ 42,
+ GNUNET_TIME_UNIT_MINUTES,
+ NULL,
+ cls_->hdr.size,
+ mesh_send,
+ cls);
+}
+
- snprintf(port_s, 6, "%d", port);
- GNUNET_OS_start_process(NULL, NULL, "gnunet-helper-hijack-dns", "gnunet-hijack-dns", port_s, NULL);
+static void
+send_mesh_query (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+
+ struct tunnel_cls *cls_ = (struct tunnel_cls*)cls;
+
+ cls_->tunnel = GNUNET_MESH_peer_request_connect_by_type(mesh_handle,
+ GNUNET_TIME_UNIT_HOURS,
+ GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
+ mesh_connect,
+ NULL,
+ cls_);
+
+ remote_pending[cls_->dns.s.id] = cls_;
}
-void unhijack(unsigned short port) {
- char port_s[5];
+static int
+receive_mesh_query (void *cls,
+ struct GNUNET_MESH_Tunnel *tunnel,
+ void **ctx,
+ const struct GNUNET_PeerIdentity *sender,
+ const struct GNUNET_MessageHeader *message,
+ const struct GNUNET_TRANSPORT_ATS_Information *atsi)
+{
+ return GNUNET_SYSERR;
+}
+
+static int
+receive_mesh_answer (void *cls,
+ struct GNUNET_MESH_Tunnel *tunnel,
+ void **ctx,
+ const struct GNUNET_PeerIdentity *sender,
+ const struct GNUNET_MessageHeader *message,
+ const struct GNUNET_TRANSPORT_ATS_Information *atsi)
+{
+ /* TODo: size check */
+ struct dns_pkt *dns = (struct dns_pkt *) (message + 1);
+
+ /* They sent us a packet we were not waiting for */
+ if (remote_pending[dns->s.id] == NULL
+ || remote_pending[dns->s.id]->tunnel != tunnel)
+ return GNUNET_SYSERR;
+ if (query_states[dns->s.id].valid != GNUNET_YES)
+ return GNUNET_SYSERR;
+ query_states[dns->s.id].valid = GNUNET_NO;
+
+ size_t len = sizeof (struct answer_packet) - 1 + sizeof (struct dns_static) + query_states[dns->s.id].namelen + sizeof (struct dns_query_line) + 2 /* To hold the pointer (as defined in RFC1035) to the name */
+ + sizeof (struct dns_record_line) - 1 + 16; /* To hold the IPv6-Address */
+
+ 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_REMOTE;
+
+ struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
+
+ if (ntohs(pdns->s.ancount) < 1)
+ {
+ free_parsed_dns_packet(pdns);
+ return GNUNET_OK;
+ }
+
+ answer->pkt.addrsize = pdns->answers[0]->data_len;
+ memcpy(answer->pkt.addr, pdns->answers[0]->data, ntohs(pdns->answers[0]->data_len));
+
+ answer->pkt.from = query_states[dns->s.id].remote_ip;
+
+ answer->pkt.to = query_states[dns->s.id].local_ip;
+ answer->pkt.dst_port = query_states[dns->s.id].local_port;
+
+ struct dns_pkt *dpkt = (struct dns_pkt *) answer->pkt.data;
+
+ dpkt->s.id = dns->s.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[dns->s.id].name,
+ query_states[dns->s.id].namelen);
+ GNUNET_free (query_states[dns->s.id].name);
+
+ struct dns_query_line *dque =
+ (struct dns_query_line *) (dpkt->data +
+ (query_states[dns->s.id].namelen));
+ dque->type = htons (28); /* AAAA */
+ dque->class = htons (1); /* IN */
+
+ char *anname =
+ (char *) (dpkt->data + (query_states[dns->s.id].namelen) +
+ sizeof (struct dns_query_line));
+ memcpy (anname, "\xc0\x0c", 2);
+
+ struct dns_record_line *drec_data =
+ (struct dns_record_line *) (dpkt->data +
+ (query_states[dns->s.id].namelen) +
+ sizeof (struct dns_query_line) + 2);
+ drec_data->type = htons (28); /* AAAA */
+ drec_data->class = htons (1); /* IN */
+
+ drec_data->ttl = pdns->answers[0]->ttl;
+ drec_data->data_len = htons (16);
+
+ /* Calculate at which offset in the packet the IPv6-Address belongs, it is
+ * filled in by the daemon-vpn */
+ answer->pkt.addroffset =
+ htons ((unsigned short) ((unsigned long) (&drec_data->data) -
+ (unsigned long) (&answer->pkt)));
+
+ GNUNET_CONTAINER_DLL_insert_after (head, tail, tail, answer);
+
+ GNUNET_SERVER_notify_transmit_ready (query_states[dns->s.id].client,
+ len,
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ &send_answer,
+ query_states[dns->s.id].client);
+
+ free_parsed_dns_packet(pdns);
+ return GNUNET_OK;
+}
+
+
+static void
+send_rev_query(void * cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+
+ struct dns_pkt_parsed* pdns = (struct dns_pkt_parsed*) cls;
+
+ unsigned short id = pdns->s.id;
+
+ free_parsed_dns_packet(pdns);
+
+ 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*/;
+
+ 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, "\xc0\x0c", 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 */
+ /* FIXME: read the TTL from block:
+ * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
+ *
+ * But how to get the seconds out of this?
+ */
+ drec_data->ttl = htonl(3600);
+
+ /* 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)));
- snprintf(port_s, 6, "%d", port);
- GNUNET_OS_start_process(NULL, NULL, "gnunet-helper-hijack-dns", "gnunet-hijack-dns", "-d", port_s, NULL);
+ 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);
}
+/**
+ * Receive a block from the dht.
+ */
+static void
+receive_dht(void *cls,
+ struct GNUNET_TIME_Absolute exp,
+ const GNUNET_HashCode *key,
+ const struct GNUNET_PeerIdentity *const *get_path,
+ const struct GNUNET_PeerIdentity *const *put_path,
+ enum GNUNET_BLOCK_Type type,
+ size_t size,
+ const void *data) {
+
+ unsigned short id = ((struct receive_dht_cls*)cls)->id;
+ struct GNUNET_DHT_GetHandle* handle = ((struct receive_dht_cls*)cls)->handle;
+ GNUNET_free(cls);
+
+ GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS);
+
+ /* If no query with this id is pending, ignore the block */
+ if (query_states[id].valid != GNUNET_YES) return;
+ query_states[id].valid = GNUNET_NO;
+
+ const struct GNUNET_DNS_Record* rec = data;
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got block of size %d, peer: %08x, desc: %08x\n",
+ size,
+ *((unsigned int*)&rec->peer),
+ *((unsigned int*)&rec->service_descriptor));
+
+ size_t len = sizeof(struct answer_packet) - 1 \
+ + sizeof(struct dns_static) \
+ + query_states[id].namelen \
+ + sizeof(struct dns_query_line) \
+ + 2 /* To hold the pointer (as defined in RFC1035) to the name */ \
+ + sizeof(struct dns_record_line) - 1 \
+ + 16; /* To hold the IPv6-Address */
+
+ 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_SERVICE;
+
+ GNUNET_CRYPTO_hash(&rec->peer,
+ sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+ &answer->pkt.service_descr.peer);
+
+ memcpy(&answer->pkt.service_descr.service_descriptor,
+ &rec->service_descriptor,
+ sizeof(GNUNET_HashCode));
+ memcpy(&answer->pkt.service_descr.service_type,
+ &rec->service_type,
+ sizeof(answer->pkt.service_descr.service_type));
+ memcpy(&answer->pkt.service_descr.ports, &rec->ports, sizeof(answer->pkt.service_descr.ports));
+
+ 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(28); /* AAAA */
+ dque->class = htons(1); /* IN */
+
+ char* anname = (char*)(dpkt->data+(query_states[id].namelen)+sizeof(struct dns_query_line));
+ memcpy(anname, "\xc0\x0c", 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(28); /* AAAA */
+ drec_data->class = htons(1); /* IN */
+
+ /* FIXME: read the TTL from block:
+ * GNUNET_TIME_absolute_get_remaining(rec->expiration_time)
+ *
+ * But how to get the seconds out of this?
+ */
+ drec_data->ttl = htonl(3600);
+ drec_data->data_len = htons(16);
+
+ /* Calculate at which offset in the packet the IPv6-Address belongs, it is
+ * filled in by the daemon-vpn */
+ answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(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);
+
+ GNUNET_DHT_get_stop(handle);
+}
+
+/**
+ * This receives a GNUNET_MESSAGE_TYPE_REHIJACK and rehijacks the DNS
+ */
+static void
+rehijack(void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message) {
+ unhijack(dnsoutport);
+ GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
+
+ GNUNET_SERVER_receive_done(client, GNUNET_OK);
+}
+
+/**
+ * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket
+ */
+static void
+receive_query(void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *message) {
+ struct query_packet* pkt = (struct query_packet*)message;
+ struct dns_pkt* dns = (struct dns_pkt*)pkt->data;
+ struct dns_pkt_parsed* pdns = parse_dns_packet(dns);
+
+ query_states[dns->s.id].valid = GNUNET_YES;
+ query_states[dns->s.id].client = client;
+ query_states[dns->s.id].local_ip = pkt->orig_from;
+ query_states[dns->s.id].local_port = pkt->src_port;
+ query_states[dns->s.id].remote_ip = pkt->orig_to;
+ query_states[dns->s.id].namelen = strlen((char*)dns->data) + 1;
+ 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))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for .gnunet!\n");
+ GNUNET_HashCode key;
+ GNUNET_CRYPTO_hash(pdns->queries[0]->name, pdns->queries[0]->namelen, &key);
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Getting with key %08x, len is %d\n",
+ *((unsigned int*)&key),
+ pdns->queries[0]->namelen);
+
+ struct receive_dht_cls* cls = GNUNET_malloc(sizeof(struct receive_dht_cls));
+ cls->id = dns->s.id;
+
+ cls->handle = GNUNET_DHT_get_start(dht,
+ GNUNET_TIME_UNIT_MINUTES,
+ GNUNET_BLOCK_TYPE_DNS,
+ &key,
+ DEFAULT_GET_REPLICATION,
+ GNUNET_DHT_RO_NONE,
+ NULL,
+ 0,
+ NULL,
+ 0,
+ receive_dht,
+ cls);
+
+ goto outfree;
+ }
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Query for '%s'; namelen=%d\n", pdns->queries[0]->name, pdns->queries[0]->namelen);
+
+ /* This is a PTR-Query. Check if it is for "our" network */
+ if (htons(pdns->queries[0]->qtype) == 12 &&
+ 74 == pdns->queries[0]->namelen)
+ {
+ char* ipv6addr;
+ char ipv6[16];
+ char ipv6rev[74] = "X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.X.ip6.arpa.";
+ unsigned int i;
+ unsigned long long ipv6prefix;
+ unsigned int comparelen;
+
+ GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_string(cfg, "vpn", "IPV6ADDR", &ipv6addr));
+ inet_pton (AF_INET6, ipv6addr, ipv6);
+ GNUNET_free(ipv6addr);
+
+ GNUNET_assert(GNUNET_OK == GNUNET_CONFIGURATION_get_value_number(cfg, "vpn", "IPV6PREFIX", &ipv6prefix));
+ GNUNET_assert(ipv6prefix < 127);
+ ipv6prefix = (ipv6prefix + 7)/8;
+
+ for (i = ipv6prefix; i < 16; i++)
+ ipv6[i] = 0;
+
+ for (i = 0; i < 16; i++)
+ {
+ unsigned char c1 = ipv6[i] >> 4;
+ unsigned char c2 = ipv6[i] & 0xf;
+
+ if (c1 <= 9)
+ ipv6rev[62-(4*i)] = c1 + '0';
+ else
+ ipv6rev[62-(4*i)] = c1 + 87; /* 87 is the difference between 'a' and 10 */
+
+ if (c2 <= 9)
+ ipv6rev[62-((4*i)+2)] = c2 + '0';
+ else
+ ipv6rev[62-((4*i)+2)] = c2 + 87;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "My network is %s'.\n", ipv6rev);
+ comparelen = 10 + 4*ipv6prefix;
+ if(0 == strncmp(pdns->queries[0]->name+(pdns->queries[0]->namelen - comparelen),
+ ipv6rev + (74 - comparelen),
+ comparelen))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Reverse-Query for .gnunet!\n");
+
+ GNUNET_SCHEDULER_add_now(send_rev_query, pdns);
+
+ goto out;
+ }
+ }
+
+ char* virt_dns;
+ int virt_dns_bytes;
+ if (GNUNET_SYSERR ==
+ GNUNET_CONFIGURATION_get_value_string (cfg, "vpn", "VIRTDNS",
+ &virt_dns))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "No entry 'VIRTDNS' in configuration!\n");
+ exit (1);
+ }
+
+ if (1 != inet_pton (AF_INET, virt_dns, &virt_dns_bytes))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Error parsing 'VIRTDNS': %s; %m!\n", virt_dns);
+ exit(1);
+ }
+
+ GNUNET_free(virt_dns);
+
+ if (virt_dns_bytes == pkt->orig_to)
+ {
+ /* This is a packet that was sent directly to the virtual dns-server
+ *
+ * This means we have to send this query over gnunet
+ */
+
+ size_t size = sizeof(struct GNUNET_MESH_Tunnel*) + sizeof(struct GNUNET_MessageHeader) + (ntohs(message->size) - sizeof(struct query_packet) + 1);
+ struct tunnel_cls *cls_ = GNUNET_malloc(size);
+ cls_->hdr.size = size - sizeof(struct GNUNET_MESH_Tunnel*);
+
+ cls_->hdr.type = ntohs(GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS);
+
+ memcpy(&cls_->dns, dns, cls_->hdr.size);
+ GNUNET_SCHEDULER_add_now(send_mesh_query, cls_);
+
+ goto out;
+ }
+
+
+ /* The query should be sent to the network */
+
+ struct sockaddr_in dest;
+ memset(&dest, 0, sizeof dest);
+ dest.sin_port = htons(53);
+ dest.sin_addr.s_addr = pkt->orig_to;
+
+ GNUNET_NETWORK_socket_sendto(dnsout,
+ dns,
+ ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1,
+ (struct sockaddr*) &dest,
+ sizeof dest);
+
+outfree:
+ free_parsed_dns_packet(pdns);
+ pdns = NULL;
+out:
+ GNUNET_SERVER_receive_done(client, GNUNET_OK);
+}
+
+static void read_response (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+static void
+open_port ()
+{
+ struct sockaddr_in addr;
+
+ dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
+ if (dnsout == NULL)
+ return;
+ memset (&addr, 0, sizeof (struct sockaddr_in));
+
+ int err = GNUNET_NETWORK_socket_bind (dnsout,
+ (struct sockaddr *) &addr,
+ sizeof (struct sockaddr_in));
+
+ if (err != GNUNET_YES)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Could not bind a port, exiting\n");
+ return;
+ }
+
+ /* Read the port we bound to */
+ socklen_t addrlen = sizeof (struct sockaddr_in);
+ err = getsockname (GNUNET_NETWORK_get_fd (dnsout),
+ (struct sockaddr *) &addr, &addrlen);
+
+ dnsoutport = htons (addr.sin_port);
+
+ GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, dnsout,
+ &read_response, NULL);
+}
+
+/**
+ * Read a response-packet of the UDP-Socket
+ */
+static void
+read_response (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) {
+ struct sockaddr_in addr;
+ socklen_t addrlen = sizeof (addr);
+ int r;
+ int len;
+
+ if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
+ return;
+
+ memset(&addr, 0, sizeof addr);
+
+#ifndef MINGW
+ if (0 != ioctl (GNUNET_NETWORK_get_fd (dnsout),
+ FIONREAD, &len))
+ {
+ unhijack(dnsoutport);
+ open_port();
+ GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
+ return;
+ }
+#else
+ /* port the code above? */
+ len = 65536;
+#endif
+ {
+ unsigned char buf[len];
+ struct dns_pkt* dns = (struct dns_pkt*)buf;
+
+ r = GNUNET_NETWORK_socket_recvfrom (dnsout,
+ buf,
+ sizeof (buf),
+ (struct sockaddr*)&addr,
+ &addrlen);
+
+ if (r < 0)
+ {
+ unhijack(dnsoutport);
+ open_port();
+ GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_SECONDS, hijack, NULL);
+ return;
+ }
+
+ if (query_states[dns->s.id].valid == GNUNET_YES)
+ {
+ query_states[dns->s.id].valid = GNUNET_NO;
+
+ size_t len = sizeof(struct answer_packet) + r - 1; /* 1 for the unsigned char data[1]; */
+ struct answer_packet_list* answer = GNUNET_malloc(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_IP;
+ answer->pkt.from = addr.sin_addr.s_addr;
+ answer->pkt.to = query_states[dns->s.id].local_ip;
+ answer->pkt.dst_port = query_states[dns->s.id].local_port;
+ memcpy(answer->pkt.data, buf, r);
+
+ GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer);
+
+ GNUNET_SERVER_notify_transmit_ready(query_states[dns->s.id].client,
+ len,
+ GNUNET_TIME_UNIT_FOREVER_REL,
+ &send_answer,
+ query_states[dns->s.id].client);
+ }
+ }
+ GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL,
+ dnsout,
+ &read_response,
+ NULL);
+}
+
+
/**
* Task run during shutdown.
*
cleanup_task (void *cls,
const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- unhijack(((struct dns_cls*)cls)->dnsoutport);
+ unhijack(dnsoutport);
+ GNUNET_DHT_disconnect(dht);
+}
+
+/**
+ * @brief Create a port-map from udp and tcp redirects
+ *
+ * @param udp_redirects
+ * @param tcp_redirects
+ *
+ * @return
+ */
+uint64_t
+get_port_from_redirects (const char *udp_redirects, const char *tcp_redirects)
+{
+ uint64_t ret = 0;
+ char* cpy, *hostname, *redirect;
+ int local_port, count = 0;
+
+ if (NULL != udp_redirects)
+ {
+ cpy = GNUNET_strdup (udp_redirects);
+ for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
+ {
+ if (NULL == (hostname = strstr (redirect, ":")))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
+ continue;
+ }
+ hostname[0] = '\0';
+ local_port = atoi (redirect);
+ if (!((local_port > 0) && (local_port < 65536)))
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
+
+ ret |= (0xFFFF & htons(local_port));
+ ret <<= 16;
+ count ++;
+
+ if(count > 4)
+ {
+ ret = 0;
+ goto out;
+ }
+ }
+ GNUNET_free(cpy);
+ cpy = NULL;
+ }
+
+ if (NULL != tcp_redirects)
+ {
+ cpy = GNUNET_strdup (tcp_redirects);
+ for (redirect = strtok (cpy, " "); redirect != NULL; redirect = strtok (NULL, " "))
+ {
+ if (NULL == (hostname = strstr (redirect, ":")))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: option %s is not formatted correctly!\n", redirect);
+ continue;
+ }
+ hostname[0] = '\0';
+ local_port = atoi (redirect);
+ if (!((local_port > 0) && (local_port < 65536)))
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Warning: %s is not a correct port.", redirect);
+
+ ret |= (0xFFFF & htons(local_port));
+ ret <<= 16;
+ count ++;
+
+ if(count > 4)
+ {
+ ret = 0;
+ goto out;
+ }
+ }
+ GNUNET_free(cpy);
+ cpy = NULL;
+ }
+
+out:
+ if (NULL != cpy)
+ GNUNET_free(cpy);
+ return ret;
+}
+
+void
+publish_name (const char *name, uint64_t ports, uint32_t service_type,
+ struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key)
+{
+ size_t size = sizeof (struct GNUNET_DNS_Record);
+ struct GNUNET_DNS_Record data;
+ memset (&data, 0, size);
+
+ data.purpose.size =
+ htonl (size - sizeof (struct GNUNET_CRYPTO_RsaSignature));
+ data.purpose.purpose = GNUNET_SIGNATURE_PURPOSE_DNS_RECORD;
+
+ GNUNET_CRYPTO_hash (name, strlen (name) + 1, &data.service_descriptor);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Store with key1 %x\n",
+ *((unsigned long long *) &data.service_descriptor));
+
+ data.service_type = service_type;
+ data.ports = ports;
+
+ GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &data.peer);
+
+ data.expiration_time =
+ GNUNET_TIME_relative_to_absolute (GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_HOURS, 2));
+
+ /* Sign the block */
+ if (GNUNET_OK != GNUNET_CRYPTO_rsa_sign (my_private_key,
+ &data.purpose, &data.signature))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not sign DNS_Record\n");
+ return;
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Putting with key %08x, size = %d\n",
+ *((unsigned int *) &data.service_descriptor), size);
+
+ GNUNET_DHT_put (dht,
+ &data.service_descriptor,
+ DEFAULT_PUT_REPLICATION,
+ GNUNET_DHT_RO_NONE,
+ GNUNET_BLOCK_TYPE_DNS,
+ size,
+ (char *) &data,
+ GNUNET_TIME_relative_to_absolute (GNUNET_TIME_UNIT_HOURS),
+ GNUNET_TIME_UNIT_MINUTES, NULL, NULL);
+}
+
+/**
+ * @brief Publishes the record defined by the section section
+ *
+ * @param cls closure
+ * @param section the current section
+ */
+void
+publish_iterate (void *cls, const char *section)
+{
+ char *udp_redirects, *tcp_redirects, *alternative_names, *alternative_name,
+ *keyfile;
+
+ GNUNET_CONFIGURATION_get_value_string (servicecfg, section,
+ "UDP_REDIRECTS", &udp_redirects);
+ GNUNET_CONFIGURATION_get_value_string (servicecfg, section, "TCP_REDIRECTS",
+ &tcp_redirects);
+
+ if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "GNUNETD",
+ "HOSTKEY",
+ &keyfile))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "could not read keyfile-value\n");
+ if (keyfile != NULL)
+ GNUNET_free (keyfile);
+ return;
+ }
+
+ struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key =
+ GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
+ GNUNET_free (keyfile);
+ GNUNET_assert (my_private_key != NULL);
+
+ uint64_t ports = get_port_from_redirects (udp_redirects, tcp_redirects);
+ uint32_t service_type = 0;
+
+ if (NULL != udp_redirects)
+ service_type = GNUNET_DNS_SERVICE_TYPE_UDP;
+
+ if (NULL != tcp_redirects)
+ service_type |= GNUNET_DNS_SERVICE_TYPE_TCP;
+
+ service_type = htonl (service_type);
+
+
+ publish_name (section, ports, service_type, my_private_key);
+
+ GNUNET_CONFIGURATION_get_value_string (servicecfg, section,
+ "ALTERNATIVE_NAMES",
+ &alternative_names);
+ for (alternative_name = strtok (alternative_names, " ");
+ alternative_name != NULL; alternative_name = strtok (NULL, " "))
+ {
+ char *altname =
+ alloca (strlen (alternative_name) + strlen (section) + 1 + 1);
+ strcpy (altname, alternative_name);
+ strcpy (altname + strlen (alternative_name) + 1, section);
+ altname[strlen (alternative_name)] = '.';
+
+ publish_name (altname, ports, service_type, my_private_key);
+ }
+
+ GNUNET_free_non_null(alternative_names);
+ GNUNET_CRYPTO_rsa_key_free (my_private_key);
+ GNUNET_free_non_null (udp_redirects);
+ GNUNET_free_non_null (tcp_redirects);
+}
+
+/**
+ * Publish a DNS-record in the DHT. This is up to now just for testing.
+ */
+static void
+publish_names (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc) {
+ char *services;
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+
+ if (NULL != servicecfg)
+ GNUNET_CONFIGURATION_destroy(servicecfg);
+
+ GNUNET_CONFIGURATION_get_value_filename(cfg, "dns", "SERVICES", &services);
+
+ servicecfg = GNUNET_CONFIGURATION_create();
+ if (GNUNET_OK == GNUNET_CONFIGURATION_parse(servicecfg, services))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Parsing services %s\n", services);
+ GNUNET_CONFIGURATION_iterate_sections(servicecfg, publish_iterate, NULL);
+ }
+ if (NULL != services)
+ GNUNET_free(services);
+
+ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS,
+ publish_names,
+ NULL);
}
/**
* @param cls closure
- * @param sched scheduler to use
* @param server the initialized server
- * @param cfg configuration to use
+ * @param cfg_ configuration to use
*/
static void
run (void *cls,
- struct GNUNET_SCHEDULER_Handle *sched,
struct GNUNET_SERVER_Handle *server,
- const struct GNUNET_CONFIGURATION_Handle *cfg)
+ const struct GNUNET_CONFIGURATION_Handle *cfg_)
{
static const struct GNUNET_SERVER_MessageHandler handlers[] = {
+ /* callback, cls, type, size */
+ {&receive_query, NULL, GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS, 0},
+ {&rehijack, NULL, GNUNET_MESSAGE_TYPE_REHIJACK,
+ sizeof (struct GNUNET_MessageHeader)},
{NULL, NULL, 0, 0}
};
- struct dns_cls* mycls = (struct dns_cls*)cls;
+ static struct GNUNET_MESH_MessageHandler *mesh_handlers;
+
+ if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno(cfg_, "dns", "PROVIDE_EXIT"))
+ mesh_handlers = (struct GNUNET_MESH_MessageHandler[]) {
+ {receive_mesh_query, GNUNET_MESSAGE_TYPE_REMOTE_QUERY_DNS, 0},
+ {NULL, 0, 0}
+ };
+ else
+ mesh_handlers = (struct GNUNET_MESH_MessageHandler[]) {
+ {receive_mesh_answer, GNUNET_MESSAGE_TYPE_REMOTE_ANSWER_DNS, 0},
+ {NULL, 0, 0}
+ };
- mycls->sched = sched;
+ const static GNUNET_MESH_ApplicationType apptypes[] =
+ { GNUNET_APPLICATION_TYPE_INTERNET_RESOLVER,
+ GNUNET_APPLICATION_TYPE_END
+ };
+
+ mesh_handle = GNUNET_MESH_connect (cfg_, NULL, NULL, mesh_handlers, apptypes);
- mycls->dnsout = GNUNET_NETWORK_socket_create (AF_INET, SOCK_DGRAM, 0);
+ cfg = cfg_;
- struct sockaddr_in * addr = alloca(sizeof(struct sockaddr_in));
- memset(addr, 0, sizeof(struct sockaddr_in));
+ unsigned int i;
+ for (i = 0; i < 65536; i++)
+ {
+ query_states[i].valid = GNUNET_NO;
+ }
- int err = GNUNET_NETWORK_socket_bind (mycls->dnsout, (struct sockaddr*)addr, sizeof(struct sockaddr_in));
- err = getsockname(GNUNET_NETWORK_get_fd(mycls->dnsout), addr, (unsigned int[]){sizeof(struct sockaddr_in)});
+ dht = GNUNET_DHT_connect (cfg, 1024);
- mycls->dnsoutport = htons(addr->sin_port);
+ open_port ();
- hijack(htons(addr->sin_port));
+ GNUNET_SCHEDULER_add_now (publish_names, NULL);
GNUNET_SERVER_add_handlers (server, handlers);
- GNUNET_SCHEDULER_add_delayed (sched,
- GNUNET_TIME_UNIT_FOREVER_REL,
- &cleanup_task,
- cls);
+ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
+ &cleanup_task, cls);
}
/**
int
main (int argc, char *const *argv)
{
- struct dns_cls* cls = GNUNET_malloc(sizeof(struct dns_cls));
-
return (GNUNET_OK ==
- GNUNET_SERVICE_run (argc,
- argv,
- "gnunet-service-dns",
+ GNUNET_SERVICE_run (argc,
+ argv,
+ "dns",
GNUNET_SERVICE_OPTION_NONE,
- &run, cls)) ? 0 : 1;
-
- GNUNET_free(cls); // Make clang happy
+ &run, NULL)) ? 0 : 1;
}
projects / oweals / gnunet.git / blobdiff