/*
This file is part of GNUnet.
- (C) 2010 Christian Grothoff (and other contributing authors)
+ (C) 2010 Christian Grothoff
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
/**
* @file vpn/gnunet-daemon-vpn.c
* @brief
- * @author Christian Grothoff
+ * @author Philipp Tölke
*/
#include "platform.h"
#include "gnunet_getopt_lib.h"
#include "gnunet_program_lib.h"
#include "gnunet_os_lib.h"
-/* #include "gnunet_template_service.h" */
+#include "gnunet-vpn-helper-p.h"
+#include "gnunet-vpn-packet.h"
+#include "gnunet-vpn-pretty-print.h"
+#include "gnunet_common.h"
+#include "gnunet_protocols.h"
+#include "gnunet_server_lib.h"
+#include "gnunet-service-dns-p.h"
+#include "gnunet_client_lib.h"
+#include "gnunet_container_lib.h"
+#include "block_dns.h"
/**
* Final status code.
static int ret;
struct vpn_cls {
- struct GNUNET_DISK_PipeHandle* helper_in;
- struct GNUNET_DISK_PipeHandle* helper_out;
+ struct GNUNET_DISK_PipeHandle* helper_in; // From the helper
+ struct GNUNET_DISK_PipeHandle* helper_out; // To the helper
+ const struct GNUNET_DISK_FileHandle* fh_from_helper;
+ const struct GNUNET_DISK_FileHandle* fh_to_helper;
+
+ struct GNUNET_SERVER_MessageStreamTokenizer* mst;
+
+ struct GNUNET_SCHEDULER_Handle *sched;
+
+ struct GNUNET_CLIENT_Connection *dns_connection;
+ unsigned char restart_hijack;
pid_t helper_pid;
+
+ const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+ struct query_packet_list *head;
+ struct query_packet_list *tail;
+
+ struct answer_packet_list *answer_proc_head;
+ struct answer_packet_list *answer_proc_tail;
};
+static struct vpn_cls mycls;
+
+size_t send_query(void* cls, size_t size, void* buf);
+
static void cleanup(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
- struct vpn_cls* mycls = (struct vpn_cls*) cls;
- if (tskctx->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN) {
- PLIBC_KILL(mycls->helper_pid, SIGTERM);
- GNUNET_OS_process_wait(mycls->helper_pid);
- }
+ GNUNET_assert (0 != (tskctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN));
+ PLIBC_KILL(mycls.helper_pid, SIGTERM);
+ GNUNET_OS_process_wait(mycls.helper_pid);
+ if (mycls.dns_connection != NULL)
+ {
+ GNUNET_CLIENT_disconnect (mycls.dns_connection, GNUNET_NO);
+ mycls.dns_connection = NULL;
+ }
+}
+
+static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx);
+
+static void start_helper_and_schedule(void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc) {
+
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+
+ mycls.helper_in = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_YES, GNUNET_NO);
+ mycls.helper_out = GNUNET_DISK_pipe (GNUNET_YES, GNUNET_NO, GNUNET_YES);
+
+ if (mycls.helper_in == NULL || mycls.helper_out == NULL) return;
+
+ mycls.helper_pid = GNUNET_OS_start_process(mycls.helper_in, mycls.helper_out, "gnunet-helper-vpn", "gnunet-helper-vpn", NULL);
+
+ mycls.fh_from_helper = GNUNET_DISK_pipe_handle (mycls.helper_out, GNUNET_DISK_PIPE_END_READ);
+ mycls.fh_to_helper = GNUNET_DISK_pipe_handle (mycls.helper_in, GNUNET_DISK_PIPE_END_WRITE);
+
+ GNUNET_DISK_pipe_close_end(mycls.helper_out, GNUNET_DISK_PIPE_END_WRITE);
+ GNUNET_DISK_pipe_close_end(mycls.helper_in, GNUNET_DISK_PIPE_END_READ);
+
+ GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
+}
+
+
+static void restart_helper(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tskctx) {
+ // Kill the helper
+ PLIBC_KILL(mycls.helper_pid, SIGKILL);
+ GNUNET_OS_process_wait(mycls.helper_pid);
+
+ /* Tell the dns-service to rehijack the dns-port
+ * The routing-table gets flushed if an interface disappears.
+ */
+ mycls.restart_hijack = 1;
+ GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, sizeof(struct GNUNET_MessageHeader), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
+
+ GNUNET_DISK_pipe_close(mycls.helper_in);
+ GNUNET_DISK_pipe_close(mycls.helper_out);
+
+ // Restart the helper
+ GNUNET_SCHEDULER_add_delayed (mycls.sched, GNUNET_TIME_UNIT_SECONDS, start_helper_and_schedule, NULL);
+
}
static void helper_read(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
+ char buf[65535];
+
+ if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
+ return;
+
+ int t = GNUNET_DISK_file_read(mycls.fh_from_helper, &buf, 65535);
+ if (t<=0) {
+ GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "Read error for header from vpn-helper: %m\n");
+ GNUNET_SCHEDULER_add_now(mycls.sched, restart_helper, cls);
+ return;
+ }
+
+ /* FIXME */ GNUNET_SERVER_mst_receive(mycls.mst, NULL, buf, t, 0, 0);
+
+ GNUNET_SCHEDULER_add_read_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_from_helper, &helper_read, NULL);
+}
+
+static uint16_t calculate_ip_checksum(uint16_t* hdr, short len) {
+ uint32_t sum = 0;
+ for(; len >= 2; len -= 2)
+ sum += *(hdr++);
+ if (len == 1)
+ sum += *((unsigned char*)hdr);
+
+ sum = (sum >> 16) + (sum & 0xFFFF);
+
+ return ~sum;
+}
+
+static void helper_write(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tsdkctx) {
+ if (tsdkctx->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)
+ return;
+ struct answer_packet_list* ans = mycls.answer_proc_head;
+ size_t len = ntohs(ans->pkt.hdr.size);
+
+ GNUNET_assert(ans->pkt.subtype == GNUNET_DNS_ANSWER_TYPE_IP);
+
+ size_t data_len = len - sizeof(struct answer_packet) + 1;
+ size_t net_len = sizeof(struct ip_hdr) + sizeof(struct udp_dns) + data_len;
+ size_t pkt_len = sizeof(struct GNUNET_MessageHeader) + sizeof(struct pkt_tun) + net_len;
+
+ struct ip_udp_dns* pkt = alloca(pkt_len);
+ memset(pkt, 0, pkt_len);
+
+ pkt->shdr.size = htons(pkt_len);
+ pkt->shdr.type = htons(GNUNET_MESSAGE_TYPE_VPN_HELPER);
+
+ pkt->tun.flags = 0;
+ pkt->tun.type = htons(0x0800);
+
+ pkt->ip_hdr.version = 4;
+ pkt->ip_hdr.hdr_lngth = 5;
+ pkt->ip_hdr.diff_serv = 0;
+ pkt->ip_hdr.tot_lngth = htons(net_len);
+ pkt->ip_hdr.ident = 0;
+ pkt->ip_hdr.flags = 0;
+ pkt->ip_hdr.frag_off = 0;
+ pkt->ip_hdr.ttl = 255;
+ pkt->ip_hdr.proto = 0x11; /* UDP */
+ pkt->ip_hdr.chks = 0; /* Will be calculated later*/
+ pkt->ip_hdr.sadr = ans->pkt.from;
+ pkt->ip_hdr.dadr = ans->pkt.to;
+
+ pkt->ip_hdr.chks = calculate_ip_checksum((uint16_t*)&pkt->ip_hdr, 5*4);
+
+ pkt->udp_dns.udp_hdr.spt = htons(53);
+ pkt->udp_dns.udp_hdr.dpt = ans->pkt.dst_port;
+ pkt->udp_dns.udp_hdr.len = htons(net_len - sizeof(struct ip_hdr));
+ pkt->udp_dns.udp_hdr.crc = 0; /* Optional for IPv4 */
+
+ memcpy(&pkt->udp_dns.data, ans->pkt.data, data_len);
+
+ GNUNET_CONTAINER_DLL_remove (mycls.answer_proc_head, mycls.answer_proc_tail, ans);
+ GNUNET_free(ans);
+
+ /* FIXME */ GNUNET_DISK_file_write(mycls.fh_to_helper, pkt, pkt_len);
+
+ if (mycls.answer_proc_head != NULL)
+ GNUNET_SCHEDULER_add_write_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_to_helper, &helper_write, NULL);
+}
+
+size_t send_query(void* cls, size_t size, void* buf)
+{
+ size_t len;
+ if (mycls.restart_hijack == 1)
+ {
+ mycls.restart_hijack = 0;
+ GNUNET_assert(sizeof(struct GNUNET_MessageHeader) >= size);
+ struct GNUNET_MessageHeader* hdr = buf;
+ len = sizeof(struct GNUNET_MessageHeader);
+ hdr->size = htons(len);
+ hdr->type = htons(GNUNET_MESSAGE_TYPE_REHIJACK);
+ }
+ else
+ {
+ struct query_packet_list* query = mycls.head;
+ len = ntohs(query->pkt.hdr.size);
+
+ GNUNET_assert(len <= size);
+
+ memcpy(buf, &query->pkt.hdr, len);
+
+ GNUNET_CONTAINER_DLL_remove (mycls.head, mycls.tail, query);
+
+ GNUNET_free(query);
+ }
+
+ if (mycls.head != NULL || mycls.restart_hijack == 1) {
+ GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, ntohs(mycls.head->pkt.hdr.size), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
+ }
+
+ return len;
+}
+
+static void message_token(void *cls, void *client, const struct GNUNET_MessageHeader *message) {
+ if (ntohs(message->type) != GNUNET_MESSAGE_TYPE_VPN_HELPER) return;
+
+ struct tun_pkt *pkt_tun = (struct tun_pkt*) message;
+
+ if (ntohs(pkt_tun->tun.type) == 0x86dd) {
+ struct ip6_pkt *pkt6 = (struct ip6_pkt*) message;
+ struct ip6_tcp *pkt6_tcp;
+ struct ip6_udp *pkt6_udp;
+
+ pkt_printf(pkt6);
+ switch(pkt6->ip6_hdr.nxthdr) {
+ case 0x06:
+ pkt6_tcp = (struct ip6_tcp*)pkt6;
+ pkt_printf_ip6tcp(pkt6_tcp);
+ break;
+ case 0x11:
+ pkt6_udp = (struct ip6_udp*)pkt6;
+ pkt_printf_ip6udp(pkt6_udp);
+ if (ntohs(pkt6_udp->udp_hdr.dpt) == 53) {
+ pkt_printf_ip6dns((struct ip6_udp_dns*)pkt6_udp);
+ }
+ break;
+ }
+ } else if (ntohs(pkt_tun->tun.type) == 0x0800) {
+ struct ip_pkt *pkt = (struct ip_pkt*) message;
+ struct ip_udp *udp = (struct ip_udp*) message;
+ GNUNET_assert(pkt->ip_hdr.version == 4);
+ if (pkt->ip_hdr.proto == 0x11 && ntohs(udp->udp_hdr.dpt) == 53 ) {
+ size_t len = sizeof(struct query_packet) + ntohs(udp->udp_hdr.len) - 9; /* 9 = 8 for the udp-header + 1 for the unsigned char data[1]; */
+ struct query_packet_list* query = GNUNET_malloc(len + 2*sizeof(struct query_packet_list*));
+ query->pkt.hdr.type = htons(GNUNET_MESSAGE_TYPE_LOCAL_QUERY_DNS);
+ query->pkt.hdr.size = htons(len);
+ query->pkt.orig_to = pkt->ip_hdr.dadr;
+ query->pkt.orig_from = pkt->ip_hdr.sadr;
+ query->pkt.src_port = udp->udp_hdr.spt;
+ memcpy(query->pkt.data, udp->data, ntohs(udp->udp_hdr.len) - 8);
+
+ GNUNET_CONTAINER_DLL_insert_after(mycls.head, mycls.tail, mycls.tail, query);
+
+ if (mycls.dns_connection != NULL)
+ /* struct GNUNET_CLIENT_TransmitHandle* th = */ GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, len, GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
+ }
+ }
+
+}
+
+static void
+dns_answer_handler(void* cls, const struct GNUNET_MessageHeader *msg);
+
+static void
+reconnect_to_service_dns (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc) {
+ if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+ return;
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connecting\n");
+ GNUNET_assert (mycls.dns_connection == NULL);
+ mycls.dns_connection = GNUNET_CLIENT_connect (mycls.sched, "dns", mycls.cfg);
+ GNUNET_CLIENT_receive(mycls.dns_connection, &dns_answer_handler, NULL, GNUNET_TIME_UNIT_FOREVER_REL);
+ if (mycls.head != NULL)
+ /* struct GNUNET_CLIENT_TransmitHandle* th = */ GNUNET_CLIENT_notify_transmit_ready(mycls.dns_connection, ntohs(mycls.head->pkt.hdr.size), GNUNET_TIME_UNIT_FOREVER_REL, GNUNET_YES, &send_query, NULL);
+}
+
+static void
+process_answer(void* cls, const struct GNUNET_SCHEDULER_TaskContext* tc) {
+ struct answer_packet* pkt = cls;
+
+ if (pkt->subtype == GNUNET_DNS_ANSWER_TYPE_SERVICE)
+ {
+ pkt->subtype = GNUNET_DNS_ANSWER_TYPE_IP;
+ unsigned char ip6addr[16];
+ memcpy(ip6addr, (int[]){htons(0x1234)}, 2);
+ memcpy(ip6addr+2, &pkt->peer, 7);
+ memcpy(ip6addr+9, &pkt->service_descriptor, 7);
+
+ memcpy(((char*)pkt)+ntohs(pkt->addroffset), ip6addr, 16);
+
+ /*FIXME:
+ * -save DNS_Record into hashmap, pointed to by ip
+ * -regularily walk through hashmap, deleting old entries
+ * when is an entry old?
+ * have a last-used field
+ * don't remove if last-used "recent", ask dht again if record expired
+ */
+ }
+
+ struct answer_packet_list* list = GNUNET_malloc(htons(pkt->hdr.size) + 2*sizeof(struct answer_packet_list*));
+
+ memcpy(&list->pkt, pkt, htons(pkt->hdr.size));
+
+ GNUNET_CONTAINER_DLL_insert_after(mycls.answer_proc_head, mycls.answer_proc_tail, mycls.answer_proc_tail, list);
+
+ GNUNET_SCHEDULER_add_write_file (mycls.sched, GNUNET_TIME_UNIT_FOREVER_REL, mycls.fh_to_helper, &helper_write, NULL);
+
+ return;
+}
+
+static void
+dns_answer_handler(void* cls, const struct GNUNET_MessageHeader *msg)
+{
+ if (msg == NULL)
+ {
+ GNUNET_CLIENT_disconnect(mycls.dns_connection, GNUNET_NO);
+ mycls.dns_connection = NULL;
+ GNUNET_SCHEDULER_add_delayed (mycls.sched,
+ GNUNET_TIME_UNIT_SECONDS,
+ &reconnect_to_service_dns,
+ NULL);
+ return;
+ }
+
+ if (msg->type != htons(GNUNET_MESSAGE_TYPE_LOCAL_RESPONSE_DNS))
+ {
+ GNUNET_break (0);
+ GNUNET_CLIENT_disconnect(mycls.dns_connection, GNUNET_NO);
+ mycls.dns_connection = NULL;
+ GNUNET_SCHEDULER_add_now (mycls.sched,
+ &reconnect_to_service_dns,
+ NULL);
+ return;
+ }
+ void *pkt = GNUNET_malloc(ntohs(msg->size));
+
+ memcpy(pkt, msg, ntohs(msg->size));
+
+ GNUNET_SCHEDULER_add_now(mycls.sched, process_answer, pkt);
+ GNUNET_CLIENT_receive(mycls.dns_connection, &dns_answer_handler, NULL, GNUNET_TIME_UNIT_FOREVER_REL);
}
/**
*/
static void
run (void *cls,
- struct GNUNET_SCHEDULER_Handle *sched,
- char *const *args,
- const char *cfgfile,
- const struct GNUNET_CONFIGURATION_Handle *cfg) {
-
- struct vpn_cls* mycls = (struct vpn_cls*) cls;
-
- GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
-
- mycls->helper_in = GNUNET_DISK_pipe(1);
- mycls->helper_out = GNUNET_DISK_pipe(1);
-
- mycls->helper_pid = GNUNET_OS_start_process(mycls->helper_in, mycls->helper_out, "gnunet-vpn-helper", "gnunet-vpn-helper", NULL);
-
- const struct GNUNET_DISK_FileHandle* fh = GNUNET_DISK_pipe_handle (mycls->helper_out, GNUNET_DISK_PIPE_END_READ);
-
- GNUNET_SCHEDULER_add_read_file (sched, GNUNET_TIME_UNIT_FOREVER_REL, fh, &helper_read, mycls);
+ struct GNUNET_SCHEDULER_Handle *sched,
+ char *const *args,
+ const char *cfgfile,
+ const struct GNUNET_CONFIGURATION_Handle *cfg)
+{
+ mycls.sched = sched;
+ mycls.mst = GNUNET_SERVER_mst_create(&message_token, NULL);
+ mycls.cfg = cfg;
+ mycls.restart_hijack = 0;
+ GNUNET_SCHEDULER_add_now (sched, &reconnect_to_service_dns, NULL);
+ GNUNET_SCHEDULER_add_delayed(sched, GNUNET_TIME_UNIT_FOREVER_REL, &cleanup, cls);
+ GNUNET_SCHEDULER_add_now (sched, start_helper_and_schedule, NULL);
}
GNUNET_GETOPT_OPTION_END
};
- struct vpn_cls* cls = (struct vpn_cls*)malloc(sizeof(struct vpn_cls));
-
return (GNUNET_OK ==
GNUNET_PROGRAM_run (argc,
argv,
"gnunet-daemon-vpn",
gettext_noop ("help text"),
- options, &run, cls)) ? ret : 1;
+ options, &run, NULL)) ? ret : 1;
}
/* end of gnunet-daemon-vpn.c */
projects / oweals / gnunet.git / blobdiff