/* * Copyright (c) 2006-2009 Bjorn Andersson , Erik Ekman * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include #include #include #include #include #ifdef WINDOWS32 #include #include #include "windows.h" HANDLE dev_handle; struct tun_data data; #define TAP_CONTROL_CODE(request,method) CTL_CODE(FILE_DEVICE_UNKNOWN, request, method, FILE_ANY_ACCESS) #define TAP_IOCTL_CONFIG_TUN TAP_CONTROL_CODE(10, METHOD_BUFFERED) #define TAP_IOCTL_SET_MEDIA_STATUS TAP_CONTROL_CODE(6, METHOD_BUFFERED) #define TAP_ADAPTER_KEY "SYSTEM\\CurrentControlSet\\Control\\Class\\{4D36E972-E325-11CE-BFC1-08002BE10318}" #define TAP_DEVICE_SPACE "\\\\.\\Global\\" #define TAP_COMPONENT_ID "tap0801" #define KEY_COMPONENT_ID "ComponentId" #define NET_CFG_INST_ID "NetCfgInstanceId" #else #include #include #include #define TUN_MAX_TRY 50 #endif #include "tun.h" #include "common.h" char if_name[50]; #ifndef WINDOWS32 #ifdef LINUX #include #include #include int open_tun(const char *tun_device) { int i; int tun_fd; struct ifreq ifreq; char *tunnel = "/dev/net/tun"; if ((tun_fd = open(tunnel, O_RDWR)) < 0) { warn("open_tun: %s: %s", tunnel, strerror(errno)); return -1; } memset(&ifreq, 0, sizeof(ifreq)); ifreq.ifr_flags = IFF_TUN; if (tun_device != NULL) { strncpy(ifreq.ifr_name, tun_device, IFNAMSIZ); ifreq.ifr_name[IFNAMSIZ-1] = '\0'; strncpy(if_name, tun_device, sizeof(if_name)); if_name[sizeof(if_name)-1] = '\0'; if (ioctl(tun_fd, TUNSETIFF, (void *) &ifreq) != -1) { printf("Opened %s\n", ifreq.ifr_name); return tun_fd; } if (errno != EBUSY) { warn("open_tun: ioctl[TUNSETIFF]: %s", strerror(errno)); return -1; } } else { for (i = 0; i < TUN_MAX_TRY; i++) { snprintf(ifreq.ifr_name, IFNAMSIZ, "dns%d", i); if (ioctl(tun_fd, TUNSETIFF, (void *) &ifreq) != -1) { printf("Opened %s\n", ifreq.ifr_name); snprintf(if_name, sizeof(if_name), "dns%d", i); return tun_fd; } if (errno != EBUSY) { warn("open_tun: ioctl[TUNSETIFF]: %s", strerror(errno)); return -1; } } warn("open_tun: Couldn't set interface name"); } return -1; } #else /* BSD */ int open_tun(const char *tun_device) { int i; int tun_fd; char tun_name[50]; if (tun_device != NULL) { snprintf(tun_name, sizeof(tun_name), "/dev/%s", tun_device); strncpy(if_name, tun_device, sizeof(if_name)); if_name[sizeof(if_name)-1] = '\0'; if ((tun_fd = open(tun_name, O_RDWR)) < 0) { warn("open_tun: %s: %s", tun_name, strerror(errno)); return -1; } printf("Opened %s\n", tun_name); return tun_fd; } else { for (i = 0; i < TUN_MAX_TRY; i++) { snprintf(tun_name, sizeof(tun_name), "/dev/tun%d", i); if ((tun_fd = open(tun_name, O_RDWR)) >= 0) { printf("Opened %s\n", tun_name); snprintf(if_name, sizeof(if_name), "tun%d", i); return tun_fd; } if (errno == ENOENT) break; } warn("open_tun: Failed to open tunneling device"); } return -1; } #endif /* !LINUX */ #else /* WINDOWS32 */ static void get_device(char *device, int device_len) { LONG status; HKEY adapter_key; int index; index = 0; status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, TAP_ADAPTER_KEY, 0, KEY_READ, &adapter_key); if (status != ERROR_SUCCESS) { warnx("Error opening registry key " TAP_ADAPTER_KEY ); return; } while (TRUE) { char name[256]; char unit[256]; char component[256]; char cid_string[256] = KEY_COMPONENT_ID; HKEY device_key; DWORD datatype; DWORD len; /* Iterate through all adapter of this kind */ len = sizeof(name); status = RegEnumKeyEx(adapter_key, index, name, &len, NULL, NULL, NULL, NULL); if (status == ERROR_NO_MORE_ITEMS) { break; } else if (status != ERROR_SUCCESS) { warnx("Error enumerating subkeys of registry key " TAP_ADAPTER_KEY ); break; } snprintf(unit, sizeof(unit), TAP_ADAPTER_KEY "\\%s", name); status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, unit, 0, KEY_READ, &device_key); if (status != ERROR_SUCCESS) { warnx("Error opening registry key %s", unit); goto next; } /* Check component id */ len = sizeof(component); status = RegQueryValueEx(device_key, cid_string, NULL, &datatype, (LPBYTE)component, &len); if (status != ERROR_SUCCESS || datatype != REG_SZ) { goto next; } if (strncmp(TAP_COMPONENT_ID, component, strlen(TAP_COMPONENT_ID)) == 0) { /* We found a TAP32 device, get its NetCfgInstanceId */ char iid_string[256] = NET_CFG_INST_ID; status = RegQueryValueEx(device_key, iid_string, NULL, &datatype, (LPBYTE) device, (DWORD *) &device_len); if (status != ERROR_SUCCESS || datatype != REG_SZ) { warnx("Error reading registry key %s\\%s on TAP device", unit, iid_string); } else { /* Done getting name of TAP device */ RegCloseKey(device_key); return; } } next: RegCloseKey(device_key); index++; } RegCloseKey(adapter_key); } DWORD WINAPI tun_reader(LPVOID arg) { struct tun_data *tun = arg; char buf[64*1024]; int len; int res; OVERLAPPED olpd; int sock; sock = open_dns(0, INADDR_ANY); olpd.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); while(TRUE) { olpd.Offset = 0; olpd.OffsetHigh = 0; res = ReadFile(tun->tun, buf, sizeof(buf), (LPDWORD) &len, &olpd); if (!res) { WaitForSingleObject(olpd.hEvent, INFINITE); res = GetOverlappedResult(dev_handle, &olpd, (LPDWORD) &len, FALSE); res = sendto(sock, buf, len, 0, (struct sockaddr*) &(tun->addr), sizeof(struct sockaddr_in)); } } return 0; } int open_tun(const char *tun_device) { char adapter[256]; char tapfile[512]; int tunfd; in_addr_t local; memset(adapter, 0, sizeof(adapter)); get_device(adapter, sizeof(adapter)); if (strlen(adapter) == 0) return -1; snprintf(tapfile, sizeof(tapfile), "%s%s.tap", TAP_DEVICE_SPACE, adapter); printf("Opening device %s\n", tapfile); dev_handle = CreateFile(tapfile, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_SYSTEM | FILE_FLAG_OVERLAPPED, NULL); if (dev_handle == INVALID_HANDLE_VALUE) { return -1; } /* TODO get name of interface */ strncpy(if_name, "dns", MIN(4, sizeof(if_name))); /* Use a UDP connection to forward packets from tun, * so we can still use select() in main code. * A thread does blocking reads on tun device and * sends data as udp to this socket */ local = htonl(0x7f000001); /* 127.0.0.1 */ tunfd = open_dns(55353, local); data.tun = dev_handle; memset(&(data.addr), 0, sizeof(data.addr)); data.addr.sin_family = AF_INET; data.addr.sin_port = htons(55353); data.addr.sin_addr.s_addr = local; CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)tun_reader, &data, 0, NULL); return tunfd; } #endif void close_tun(int tun_fd) { if (tun_fd >= 0) close(tun_fd); } int write_tun(int tun_fd, char *data, size_t len) { #if defined (FREEBSD) || defined (DARWIN) || defined(NETBSD) || defined(WINDOWS32) data += 4; len -= 4; #else /* !FREEBSD/DARWIN */ #ifdef LINUX data[0] = 0x00; data[1] = 0x00; data[2] = 0x08; data[3] = 0x00; #else /* OPENBSD */ data[0] = 0x00; data[1] = 0x00; data[2] = 0x00; data[3] = 0x02; #endif /* !LINUX */ #endif /* FREEBSD */ #ifndef WINDOWS32 if (write(tun_fd, data, len) != len) { warn("write_tun"); return 1; } #else /* WINDOWS32 */ { DWORD written; DWORD res; OVERLAPPED olpd; olpd.Offset = 0; olpd.OffsetHigh = 0; olpd.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); res = WriteFile(dev_handle, data, len, &written, &olpd); if (!res && GetLastError() == ERROR_IO_PENDING) { WaitForSingleObject(olpd.hEvent, INFINITE); res = GetOverlappedResult(dev_handle, &olpd, &written, FALSE); if (written != len) { return -1; } } } #endif return 0; } ssize_t read_tun(int tun_fd, char *buf, size_t len) { #if defined (FREEBSD) || defined (DARWIN) || defined(NETBSD) || defined(WINDOWS32) /* FreeBSD/Darwin/NetBSD has no header */ int bytes; bytes = recv(tun_fd, buf + 4, len, 0); if (bytes < 0) { return bytes; } else { return bytes + 4; } #else /* !FREEBSD */ return read(tun_fd, buf, len); #endif /* !FREEBSD */ } int tun_setip(const char *ip, int netbits) { char cmdline[512]; int netmask; struct in_addr net; int i; #ifndef LINUX int r; #endif #ifdef WINDOWS32 DWORD status; DWORD ipdata[3]; struct in_addr addr; DWORD len; #endif netmask = 0; for (i = 0; i < netbits; i++) { netmask = (netmask << 1) | 1; } netmask <<= (32 - netbits); net.s_addr = htonl(netmask); if (inet_addr(ip) == INADDR_NONE) { printf("Invalid IP: %s!\n", ip); return 1; } #ifndef WINDOWS32 snprintf(cmdline, sizeof(cmdline), "/sbin/ifconfig %s %s %s netmask %s", if_name, ip, ip, inet_ntoa(net)); printf("Setting IP of %s to %s\n", if_name, ip); #ifndef LINUX r = system(cmdline); if(r != 0) { return r; } else { snprintf(cmdline, sizeof(cmdline), "/sbin/route add %s/%d %s", ip, netbits, ip); } printf("Adding route %s/%d to %s\n", ip, netbits, ip); #endif return system(cmdline); #else /* WINDOWS32 */ /* Set device as connected */ printf("Enabling interface '%s'\n", if_name); status = 1; r = DeviceIoControl(dev_handle, TAP_IOCTL_SET_MEDIA_STATUS, &status, sizeof(status), &status, sizeof(status), &len, NULL); if (!r) { return -1; } ipdata[2] = (DWORD) net.s_addr; if (inet_aton(ip, &addr)) { ipdata[0] = (DWORD) addr.s_addr; ipdata[1] = ipdata[2] & ipdata[0]; /* Get network bits */ } else { return -1; } /* Tell ip/network addr/netmask to device for arp use */ r = DeviceIoControl(dev_handle, TAP_IOCTL_CONFIG_TUN, &ipdata, sizeof(ipdata), &ipdata, sizeof(ipdata), &len, NULL); if (!r) { return -1; } /* TODO use netsh to set ip address */ cmdline[0] = 0; return 0; #endif } int tun_setmtu(const unsigned mtu) { #ifndef WINDOWS32 char cmdline[512]; if (mtu > 200 && mtu < 1500) { snprintf(cmdline, sizeof(cmdline), "/sbin/ifconfig %s mtu %u", if_name, mtu); printf("Setting MTU of %s to %u\n", if_name, mtu); return system(cmdline); } else { warn("MTU out of range: %u\n", mtu); } return 1; #else /* WINDOWS32 */ return 0; #endif }