[GNUnet-SVN] r12624 - gnunet/src/transport

[gnunet]

Author: nevans
Date: 2010-08-18 17:37:41 +0200 (Wed, 18 Aug 2010)
New Revision: 12624

Added:
   gnunet/src/transport/gnunet-nat-client-windows.c
Modified:
   gnunet/src/transport/Makefile.am
Log:
windoze suckssss

Modified: gnunet/src/transport/Makefile.am
===================================================================
--- gnunet/src/transport/Makefile.am    2010-08-18 15:26:21 UTC (rev 12623)
+++ gnunet/src/transport/Makefile.am    2010-08-18 15:37:41 UTC (rev 12624)
@@ -6,8 +6,10 @@
   WINFLAGS = -Wl,--no-undefined -Wl,--export-all-symbols
   NATBIN = gnunet-nat-server
   NATSERVER = gnunet-nat-server-windows.c
+  NATSERVER = gnunet-nat-client-windows.c
 else
   NATSERVER = gnunet-nat-server.c
+  NATCLIENT = gnunet-nat-client.c
 endif
 
 if HAVE_MHD
@@ -78,7 +80,7 @@
  -lpcap
 
 gnunet_nat_client_SOURCES = \
- gnunet-nat-client.c         
+ $(NATCLIENT)         
 
 gnunet_transport_SOURCES = \
  gnunet-transport.c         

Added: gnunet/src/transport/gnunet-nat-client-windows.c
===================================================================
--- gnunet/src/transport/gnunet-nat-client-windows.c                            
(rev 0)
+++ gnunet/src/transport/gnunet-nat-client-windows.c    2010-08-18 15:37:41 UTC 
(rev 12624)
@@ -0,0 +1,457 @@
+/*
+     This file is part of GNUnet.
+     (C) 2010 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     GNUnet is distributed in the hope that it will be useful, but
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file src/transport/gnunet-nat-client-windows.c
+ * @brief Tool to help bypass NATs using ICMP method; must run as
+ *        root (SUID will do) or administrator on W32
+ *        This code will work under GNU/Linux or W32.
+ * @author Nathan Evans
+ *
+ * This program will send ONE ICMP message using RAW sockets
+ * to the IP address specified as the second argument.  Since
+ * it uses RAW sockets, it must be installed SUID or run as 'root'.
+ * In order to keep the security risk of the resulting SUID binary
+ * minimal, the program ONLY opens the RAW socket with root
+ * privileges, then drops them and only then starts to process
+ * command line arguments.  The code also does not link against
+ * any shared libraries (except libc) and is strictly minimal
+ * (except for checking for errors).  The following list of people
+ * have reviewed this code and considered it safe since the last
+ * modification (if you reviewed it, please have your name added
+ * to the list):
+ *
+ * - Christian Grothoff
+ * - Nathan Evans
+ */
+#define _GNU_SOURCE
+#ifdef WIN32
+#include <winsock2.h>
+#else
+#include <sys/types.h> 
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <sys/select.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/in.h>
+#endif
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <time.h>
+
+
+#ifdef WIN32
+typedef unsigned int uid_t;
+typedef SOCKET Socket;
+typedef unsigned short ushort;
+#define ICMP_ECHO 8
+#define IPDEFTTL        64              /* default ttl, from RFC 1340 */
+#define ICMP_TIME_EXCEEDED      11      /* Time Exceeded                */
+#define IP_HDRINCL      3       /* int; Header is included with data.  */
+#else
+typedef int Socket;
+#endif
+
+/**
+ * Must match IP given in the server.
+ */
+#define DUMMY_IP "192.0.2.86"
+
+#define NAT_TRAV_PORT 22225
+
+struct ip_packet 
+{
+  uint8_t vers_ihl;
+  uint8_t tos;
+  uint16_t pkt_len;
+  uint16_t id;
+  uint16_t flags_frag_offset;
+  uint8_t ttl;
+  uint8_t proto;
+  uint16_t checksum;
+  uint32_t src_ip;
+  uint32_t dst_ip;
+};
+
+struct icmp_packet 
+{
+  uint8_t type;
+  uint8_t code;
+  uint16_t checksum;
+  uint32_t reserved;
+
+};
+
+struct icmp_echo_packet
+{
+  uint8_t type;
+  uint8_t code;
+  uint16_t checksum;
+  uint32_t reserved;
+  uint32_t data;
+};
+
+struct udp_packet
+{
+  uint16_t src_port;
+
+  uint16_t dst_port;
+
+  uint32_t length;
+};
+
+static Socket rawsock;
+
+static struct in_addr dummy;
+ 
+static uint32_t port;
+
+#if WIN32
+/**
+ * @param af address family
+ * @param cp the address to print
+ * @param buf where to write the address result
+ */
+static int inet_pton (int af, char *cp, struct in_addr *buf)
+{
+  //ret = WSAStringToAddress (cp, af, NULL, (LPSOCKADDR)buf, &ssize);
+  buf->s_addr = inet_addr(cp);
+  if (buf->s_addr == INADDR_NONE)
+    {
+      fprintf(stderr, "Error %d handling address %s", WSAGetLastError(), cp);
+      return 0;
+    }
+  else
+    return 1;
+}
+#endif
+
+static uint16_t 
+calc_checksum(const uint16_t *data, 
+             unsigned int bytes)
+{
+  uint32_t sum;
+  unsigned int i;
+
+  sum = 0;
+  for (i=0;i<bytes/2;i++) 
+    sum += data[i];        
+  sum = (sum & 0xffff) + (sum >> 16);
+  sum = htons(0xffff - sum);
+  return sum;
+}
+
+
+static void
+make_echo (const struct in_addr *src_ip,
+          struct icmp_echo_packet *echo, uint32_t num)
+{
+  memset(echo, 0, sizeof(struct icmp_echo_packet));
+  echo->type = ICMP_ECHO;
+  echo->code = 0;
+  echo->reserved = 0;
+  echo->checksum = 0;
+  echo->data = htons(num);
+  echo->checksum = htons(calc_checksum((uint16_t*)echo, 
+                                      sizeof (struct icmp_echo_packet)));
+}
+
+
+/**
+ * Send an ICMP message to the target.
+ *
+ * @param my_ip source address
+ * @param other target address
+ */
+static void
+send_icmp_udp (const struct in_addr *my_ip,
+               const struct in_addr *other)
+{
+  struct ip_packet ip_pkt;
+  struct icmp_packet icmp_pkt;
+  struct udp_packet udp_pkt;
+
+  struct sockaddr_in dst;
+  char packet[sizeof(ip_pkt) * 2 + sizeof(icmp_pkt) * 2 + sizeof(uint32_t)];
+
+  size_t off;
+  int err;
+
+  /* ip header: send to (known) ip address */
+  off = 0;
+  memset(&ip_pkt, 0, sizeof(ip_pkt));
+  ip_pkt.vers_ihl = 0x45;
+  ip_pkt.tos = 0;
+  ip_pkt.pkt_len = htons(sizeof (packet));
+  ip_pkt.id = htons(256);
+  ip_pkt.flags_frag_offset = 0;
+  ip_pkt.ttl = 128;
+  ip_pkt.proto = IPPROTO_ICMP;
+  ip_pkt.checksum = 0;
+  ip_pkt.src_ip = my_ip->s_addr;
+  ip_pkt.dst_ip = other->s_addr;
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
+  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
+  off += sizeof(ip_pkt);
+
+  /* ip header of the presumably 'lost' udp packet */
+  ip_pkt.vers_ihl = 0x45;
+  ip_pkt.tos = 0;
+  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct 
icmp_echo_packet));
+
+  icmp_pkt.type = 11; /* TTL exceeded */
+  icmp_pkt.code = 0;
+  icmp_pkt.checksum = 0;
+  icmp_pkt.reserved = 0;
+  memcpy(&packet[off], &icmp_pkt, sizeof(icmp_pkt));
+  off += sizeof(icmp_pkt);
+
+  /* build inner IP header */
+  memset(&ip_pkt, 0, sizeof(ip_pkt));
+  ip_pkt.vers_ihl = 0x45;
+  ip_pkt.tos = 0;
+  ip_pkt.pkt_len = htons(sizeof (ip_pkt) + sizeof(udp_pkt));
+  ip_pkt.id = htons(0);
+  ip_pkt.flags_frag_offset = 0;
+  ip_pkt.ttl = 128;
+  ip_pkt.proto = IPPROTO_UDP;
+  ip_pkt.checksum = 0;
+  ip_pkt.src_ip = other->s_addr;
+  ip_pkt.dst_ip = dummy.s_addr;
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
+  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
+  off += sizeof(ip_pkt);
+
+  /* build UDP header */
+  udp_pkt.src_port = htons(NAT_TRAV_PORT); /* FIXME: does this port matter? */
+  udp_pkt.dst_port = htons(NAT_TRAV_PORT);
+
+  memset(&udp_pkt.length, 0, sizeof(uint32_t));
+  udp_pkt.length = htonl(port);
+  memcpy(&packet[off], &udp_pkt, sizeof(udp_pkt));
+  off += sizeof(udp_pkt);
+
+  /* set ICMP checksum */
+  icmp_pkt.checksum = htons(calc_checksum((uint16_t*)&packet[sizeof(ip_pkt)],
+                            sizeof (icmp_pkt) + sizeof(ip_pkt) + 
sizeof(udp_pkt)));
+  memcpy (&packet[sizeof(ip_pkt)], &icmp_pkt, sizeof (icmp_pkt));
+
+
+  memset (&dst, 0, sizeof (dst));
+  dst.sin_family = AF_INET;
+  dst.sin_addr = *other;
+  err = sendto(rawsock,
+               packet,
+               off, 0,
+               (struct sockaddr*)&dst,
+               sizeof(dst));
+
+  if (err < 0)
+    {
+      fprintf(stderr,
+              "sendto failed: %s\n", strerror(errno));
+    }
+  else if (err != off)
+    {
+      fprintf(stderr,
+              "Error: partial send of ICMP message\n");
+    }
+}
+
+
+/**
+ * Send an ICMP message to the target.
+ *
+ * @param my_ip source address
+ * @param other target address
+ */
+static void
+send_icmp (const struct in_addr *my_ip,
+          const struct in_addr *other)
+{
+  struct ip_packet ip_pkt;
+  struct icmp_packet *icmp_pkt;
+  struct icmp_echo_packet icmp_echo;
+  struct sockaddr_in dst;
+  char packet[sizeof (struct ip_packet)*2 + sizeof (struct icmp_packet) + 
sizeof(struct icmp_echo_packet)];
+
+  size_t off;
+  int err;
+
+  /* ip header: send to (known) ip address */
+  off = 0;
+  memset(&ip_pkt, 0, sizeof(ip_pkt));
+  ip_pkt.vers_ihl = 0x45;
+  ip_pkt.tos = 0;
+  ip_pkt.pkt_len = sizeof (packet); /* huh? */
+  ip_pkt.id = 1; 
+  ip_pkt.flags_frag_offset = 0;
+  ip_pkt.ttl = IPDEFTTL;
+  ip_pkt.proto = IPPROTO_ICMP;
+  ip_pkt.checksum = 0; 
+  ip_pkt.src_ip = my_ip->s_addr;
+  ip_pkt.dst_ip = other->s_addr;
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct 
ip_packet)));
+  memcpy (packet, &ip_pkt, sizeof (struct ip_packet));
+  off += sizeof (ip_pkt);
+  /* icmp reply: time exceeded */
+  icmp_pkt = (struct icmp_packet*) &packet[off];
+  memset(icmp_pkt, 0, sizeof(struct icmp_packet));
+  icmp_pkt->type = ICMP_TIME_EXCEEDED;
+  icmp_pkt->code = 0; 
+  icmp_pkt->reserved = 0;
+  icmp_pkt->checksum = 0;
+
+  off += sizeof (struct icmp_packet);
+
+  /* ip header of the presumably 'lost' udp packet */
+  ip_pkt.vers_ihl = 0x45;
+  ip_pkt.tos = 0;
+  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct 
icmp_echo_packet));
+
+  ip_pkt.id = 1; 
+  ip_pkt.flags_frag_offset = 0;
+  ip_pkt.ttl = 1; /* real TTL would be 1 on a time exceeded packet */
+  ip_pkt.proto = IPPROTO_ICMP;
+  ip_pkt.src_ip = other->s_addr;
+  ip_pkt.dst_ip = dummy.s_addr;
+  ip_pkt.checksum = 0;
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct 
ip_packet)));  
+  memcpy (&packet[off], &ip_pkt, sizeof (struct ip_packet));
+  off += sizeof (struct ip_packet);
+
+  make_echo (other, &icmp_echo, port);
+  memcpy (&packet[off], &icmp_echo, sizeof(struct icmp_echo_packet));
+  off += sizeof (struct icmp_echo_packet);
+
+  icmp_pkt->checksum = htons(calc_checksum((uint16_t*)icmp_pkt,
+                                             sizeof (struct icmp_packet) + 
sizeof(struct ip_packet) + sizeof(struct icmp_echo_packet)));
+
+  memset (&dst, 0, sizeof (dst));
+  dst.sin_family = AF_INET;
+  dst.sin_addr = *other;
+  err = sendto(rawsock, 
+              packet, 
+              off, 0, 
+              (struct sockaddr*)&dst, 
+              sizeof(dst)); /* or sizeof 'struct sockaddr'? */
+  if (err < 0) 
+    {
+      fprintf(stderr,
+             "sendto failed: %s\n", strerror(errno));
+    }
+  else if (err != off) 
+    {
+      fprintf(stderr,
+             "Error: partial send of ICMP message\n");
+    }
+}
+
+
+static Socket
+make_raw_socket ()
+{
+  const int one = 1;
+  int ret;
+
+  ret = socket (AF_INET, SOCK_RAW, IPPROTO_RAW);
+  if (-1 == ret)
+    {
+      fprintf (stderr,
+              "Error opening RAW socket: %s\n",
+              strerror (errno));
+      return -1;
+    }  
+  if (setsockopt(ret, SOL_SOCKET, SO_BROADCAST,
+                (char *)&one, sizeof(one)) == -1)
+    fprintf(stderr,
+           "setsockopt failed: %s\n",
+           strerror (errno));
+  if (setsockopt(ret, IPPROTO_IP, IP_HDRINCL,
+                (char *)&one, sizeof(one)) == -1)
+    fprintf(stderr,
+           "setsockopt failed: %s\n",
+           strerror (errno));
+  return ret;
+}
+
+
+int
+main (int argc, char *const *argv)
+{
+  struct in_addr external;
+  struct in_addr target;
+#ifndef WIN32
+  uid_t uid;
+#endif
+
+#ifdef WIN32
+  // WSA startup
+  WSADATA wsaData;
+  if (WSAStartup (MAKEWORD (2, 1), &wsaData) != 0)
+  {
+      fprintf (stderr, "Failed to find Winsock 2.1 or better.\n");
+      return 4;                       // ERROR
+  }
+#endif
+
+  if (-1 == (rawsock = make_raw_socket()))
+    return 1;
+
+#ifndef WIN32
+  uid = getuid ();
+  if (0 != setresuid (uid, uid, uid))
+    fprintf (stderr,
+            "Failed to setresuid: %s\n",
+            strerror (errno));
+#endif
+  if (argc != 4)
+    {
+      fprintf (stderr,
+              "This program must be started with our IP, the targets external 
IP, and our port as arguments.\n");
+      return 1;
+    }
+  port = atoi(argv[3]);
+
+  if ( (1 != inet_pton (AF_INET, argv[1], &external)) ||
+       (1 != inet_pton (AF_INET, argv[2], &target)) )
+    {
+      fprintf (stderr,
+              "Error parsing IPv4 address: %s\n",
+              strerror (errno));
+      return 1;
+    }
+  if (1 != inet_pton (AF_INET, DUMMY_IP, &dummy)) abort ();
+  send_icmp (&external,
+            &target);
+  send_icmp_udp (&external,
+             &target);
+  close (rawsock);
+  return 0;
+}
+
+/* end of gnunet-nat-client.c */