X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=src%2Fvpn%2Fgnunet-service-dns.c;h=02dc16494f78e12bea29117ef9f39f1345f8124f;hb=2f1ab9bfd9b7417b5f9ba47e47ce39a17e2ea27c;hp=c3d1364064289760b1dd6594f5f7d193c52ce97b;hpb=11c2830064ec60af2b84a9b7f885b2f9d31a1b0d;p=oweals%2Fgnunet.git diff --git a/src/vpn/gnunet-service-dns.c b/src/vpn/gnunet-service-dns.c index c3d136406..02dc16494 100644 --- a/src/vpn/gnunet-service-dns.c +++ b/src/vpn/gnunet-service-dns.c @@ -39,259 +39,452 @@ #include "gnunet_crypto_lib.h" #include "gnunet_signatures.h" -static struct GNUNET_SCHEDULER_Handle *sched; - +/** + * 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; -static struct GNUNET_DHT_Handle *dht; - +/** + * 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; +/** + * 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; -struct dns_query_id_state { - unsigned valid:1; - struct GNUNET_SERVER_Client* client; - unsigned local_ip:32; - unsigned remote_ip:32; - unsigned local_port:16; - char* name; - unsigned namelen:8; +/** + * A structure containing a mapping from network-byte-ordered DNS-id 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; + unsigned local_ip:32; + unsigned remote_ip:32; + unsigned local_port:16; + char* name; + unsigned namelen:8; +} query_states[65536]; + +/** + * A struct used to give more than one value as + * closure to receive_dht + */ +struct receive_dht_cls { + unsigned short id; + struct GNUNET_DHT_GetHandle* handle; }; -static struct dns_query_id_state query_states[65536]; /* This is < 1.5MiB */ -void hijack(unsigned short port) { - char port_s[6]; +/** + * 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]; + + 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)); +} - 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); +/** + * Delete the hijacking-routes + */ +static void +unhijack(unsigned short port) { + char port_s[6]; + + GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port); + snprintf(port_s, 6, "%d", port); + GNUNET_OS_start_process(NULL, + NULL, + "gnunet-helper-hijack-dns", + "gnunet-hijack-dns", + "-d", + port_s, + NULL); } -void unhijack(unsigned short port) { - char port_s[6]; +/** + * 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); - GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "unHijacking, port is %d\n", port); - snprintf(port_s, 6, "%d", port); - GNUNET_OS_start_process(NULL, NULL, "gnunet-helper-hijack-dns", "gnunet-hijack-dns", "-d", port_s, NULL); -} + memcpy(buf, &query->pkt.hdr, len); -size_t send_answer(void* cls, size_t size, void* buf); + GNUNET_CONTAINER_DLL_remove (head, tail, query); -struct receive_dht_cls { - unsigned short id; - struct GNUNET_DHT_GetHandle* handle; -}; + GNUNET_free(query); -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); + /* 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); - GNUNET_assert(type == GNUNET_BLOCK_TYPE_DNS); + 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; - if (query_states[id].valid != GNUNET_YES) return; - query_states[id].valid = GNUNET_NO; + unsigned short id = pdns->s.id; - 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)); + if (query_states[id].valid != GNUNET_YES) return; + query_states[id].valid = GNUNET_NO; - 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 to the name */ \ - + sizeof(struct dns_record_line) - 1 \ - + 16; - ; - struct answer_packet_list* answer = GNUNET_malloc(len + 2*sizeof(struct answer_packet_list*)); - memset(answer, 0, len + 2*sizeof(struct answer_packet_list*)); + GNUNET_assert(query_states[id].namelen == 74); - 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; + 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... */ ; - GNUNET_CRYPTO_hash(&rec->peer, sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded), &answer->pkt.peer); - memcpy(&answer->pkt.service_descriptor, &rec->service_descriptor, sizeof(GNUNET_HashCode)); - memcpy(&answer->pkt.service_type, &rec->service_type, sizeof(answer->pkt.service_type)); - memcpy(&answer->pkt.ports, &rec->ports, sizeof(answer->pkt.ports)); + 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.from = query_states[id].remote_ip; + 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.to = query_states[id].local_ip; - answer->pkt.dst_port = query_states[id].local_port; + answer->pkt.from = query_states[id].remote_ip; - struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data; + answer->pkt.to = query_states[id].local_ip; + answer->pkt.dst_port = query_states[id].local_port; - 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); + struct dns_pkt *dpkt = (struct dns_pkt*)answer->pkt.data; - memcpy(dpkt->data, query_states[id].name, query_states[id].namelen); - GNUNET_free(query_states[id].name); + 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); - dque->class = htons(1); + 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); + 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(28); /* AAAA */ - drec_data->class = htons(1); /* IN */ - drec_data->ttl = htonl(3600); /* FIXME: read from block */ - drec_data->data_len = htons(16); + 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 */ - answer->pkt.addroffset = htons((unsigned short)((unsigned long)(&drec_data->data)-(unsigned long)(&answer->pkt))); + /* 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_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_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); + /* + * build + * complete dns-packet with empty name in the answer + * provide offsett of the name + */ +} + +/** + * 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, (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(28); /* AAAA */ + drec_data->class = htons(1); /* IN */ + drec_data->ttl = htonl(3600); /* FIXME: read from block */ + 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 */ -void rehijack(void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { +static void +rehijack(void *cls, + 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); } /** * This receives the dns-payload from the daemon-vpn and sends it on over the udp-socket */ -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); - - 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, - GNUNET_DHT_RO_NONE, - NULL, - 0, - NULL, - 0, - receive_dht, - cls); - - goto out; - } - - /* The query should be sent to the network */ - GNUNET_free(pdns); - - struct sockaddr_in dest; - memset(&dest, 0, sizeof dest); - dest.sin_port = htons(53); - dest.sin_addr.s_addr = pkt->orig_to; - - /* int r = */ GNUNET_NETWORK_socket_sendto(dnsout, dns, ntohs(pkt->hdr.size) - sizeof(struct query_packet) + 1, (struct sockaddr*) &dest, sizeof dest); - +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; + } + + /* 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; + } + + /* 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); -} - -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); - - if (head != NULL) { - GNUNET_SERVER_notify_transmit_ready(cls, ntohs(head->pkt.hdr.size), GNUNET_TIME_UNIT_FOREVER_REL, &send_answer, cls); - } - - return len; + GNUNET_SERVER_receive_done(client, GNUNET_OK); } -static void read_response (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { - unsigned char buf[65536]; - struct dns_pkt* dns = (struct dns_pkt*)buf; - - if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) - return; - - struct sockaddr_in addr; - memset(&addr, 0, sizeof addr); - unsigned int addrlen = sizeof addr; - - int r; - r = GNUNET_NETWORK_socket_recvfrom(dnsout, buf, 65536, (struct sockaddr*)&addr, &addrlen); - - /* if (r < 0) TODO */ - - 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); +/** + * Read a response-packet of the UDP-Socket + */ +static void +read_response (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { + unsigned char buf[65536]; + struct dns_pkt* dns = (struct dns_pkt*)buf; - GNUNET_CONTAINER_DLL_insert_after(head, tail, tail, answer); + if (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) + return; - /* struct GNUNET_CONNECTION_TransmitHandle* th = */ 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); - } + struct sockaddr_in addr; + memset(&addr, 0, sizeof addr); + socklen_t addrlen = sizeof addr; + + int r; + r = GNUNET_NETWORK_socket_recvfrom(dnsout, + buf, + 65536, + (struct sockaddr*)&addr, + &addrlen); + + /* if (r < 0) FIXME */ + + 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(sched, GNUNET_TIME_UNIT_FOREVER_REL, dnsout, &read_response, NULL); + GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL, + dnsout, + &read_response, + NULL); } @@ -305,69 +498,77 @@ static void cleanup_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { - unhijack(dnsoutport); - GNUNET_DHT_disconnect(dht); + unhijack(dnsoutport); + GNUNET_DHT_disconnect(dht); } +/** + * Publish a DNS-record in the DHT. This is up to now just for testing. + */ static void publish_name (void *cls, - const struct GNUNET_SCHEDULER_TaskContext *tc) -{ - if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) - return; + const struct GNUNET_SCHEDULER_TaskContext *tc) { + if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) + return; - char* name = "philipptoelke.gnunet."; - size_t size = sizeof(struct GNUNET_DNS_Record); - struct GNUNET_DNS_Record data; - memset(&data, 0, size); + char* name = "philipptoelke.gnunet."; + 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; + 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_CRYPTO_hash(name, strlen(name)+1, &data.service_descriptor); - char* keyfile; - 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; - } + data.service_type = htonl(GNUNET_DNS_SERVICE_TYPE_UDP); + data.ports = htons(69); - struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file(keyfile); - GNUNET_free(keyfile); + char* keyfile; + 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; + } - GNUNET_CRYPTO_rsa_key_get_public(my_private_key, &data.peer); + struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file(keyfile); + GNUNET_free(keyfile); - data.expiration_time = GNUNET_TIME_relative_to_absolute(GNUNET_TIME_UNIT_HOURS); + GNUNET_CRYPTO_rsa_key_get_public(my_private_key, &data.peer); - /* Sign the block - */ + data.expiration_time = GNUNET_TIME_relative_to_absolute(GNUNET_TIME_UNIT_HOURS); - 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_free(my_private_key); - - GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Putting with key %08x\n", *((unsigned int*)&data.service_descriptor)); - - GNUNET_DHT_put(dht, - &data.service_descriptor, - 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); - - GNUNET_SCHEDULER_add_delayed (sched, GNUNET_TIME_UNIT_HOURS, publish_name, NULL); + /* 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_CRYPTO_rsa_key_free(my_private_key); + + GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, + "Putting with key %08x\n", + *((unsigned int*)&data.service_descriptor)); + + 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); + + GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_HOURS, + publish_name, + NULL); } /** @@ -378,28 +579,24 @@ publish_name (void *cls, */ static void run (void *cls, - struct GNUNET_SCHEDULER_Handle *sched_, struct GNUNET_SERVER_Handle *server, 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} + /* 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} }; cfg = cfg_; - sched = sched_; - { - int i; + unsigned int i; for (i = 0; i < 65536; i++) { - query_states[i].valid = GNUNET_NO; - } + query_states[i].valid = GNUNET_NO; } - dht = GNUNET_DHT_connect(sched, cfg, 1024); + dht = GNUNET_DHT_connect(cfg, 1024); struct sockaddr_in addr; @@ -413,9 +610,11 @@ run (void *cls, sizeof(struct sockaddr_in)); if (err != GNUNET_YES) { - GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Could not bind a port, exiting\n"); - return; + 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, @@ -423,17 +622,14 @@ run (void *cls, dnsoutport = htons(addr.sin_port); - hijack(htons(addr.sin_port)); - - GNUNET_SCHEDULER_add_now (sched, publish_name, NULL); + GNUNET_SCHEDULER_add_now (publish_name, NULL); - GNUNET_SCHEDULER_add_read_net(sched, GNUNET_TIME_UNIT_FOREVER_REL, dnsout, &read_response, NULL); + GNUNET_SCHEDULER_add_read_net(GNUNET_TIME_UNIT_FOREVER_REL, dnsout, &read_response, 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); } /** @@ -447,9 +643,9 @@ int main (int argc, char *const *argv) { return (GNUNET_OK == - GNUNET_SERVICE_run (argc, - argv, - "dns", + GNUNET_SERVICE_run (argc, + argv, + "dns", GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1; }