WireGuard rework for Linux

client/platforms/linux/daemon/iputilslinux.cpp

@@ -0,0 +1,150 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "iputilslinux.h"
+
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include <QHostAddress>
+#include <QScopeGuard>
+
+#include "daemon/wireguardutils.h"
+#include "leakdetector.h"
+#include "logger.h"
+
+constexpr uint32_t ETH_MTU = 1500;
+constexpr uint32_t WG_MTU_OVERHEAD = 80;
+
+namespace {
+Logger logger("IPUtilsLinux");
+}
+
+IPUtilsLinux::IPUtilsLinux(QObject* parent) : IPUtils(parent) {
+  MZ_COUNT_CTOR(IPUtilsLinux);
+  logger.debug() << "IPUtilsLinux created.";
+}
+
+IPUtilsLinux::~IPUtilsLinux() {
+  MZ_COUNT_DTOR(IPUtilsLinux);
+  logger.debug() << "IPUtilsLinux destroyed.";
+}
+
+bool IPUtilsLinux::addInterfaceIPs(const InterfaceConfig& config) {
+  return addIP4AddressToDevice(config) && addIP6AddressToDevice(config);
+}
+
+bool IPUtilsLinux::setMTUAndUp(const InterfaceConfig& config) {
+  Q_UNUSED(config);
+
+  // Create socket file descriptor to perform the ioctl operations on
+  int sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
+  if (sockfd < 0) {
+    logger.error() << "Failed to create ioctl socket.";
+    return false;
+  }
+  auto guard = qScopeGuard([&] { close(sockfd); });
+
+  // Setup the interface to interact with
+  struct ifreq ifr;
+  strncpy(ifr.ifr_name, WG_INTERFACE, IFNAMSIZ);
+
+  // MTU
+  // FIXME: We need to know how many layers deep this particular
+  // interface is into a tunnel to work effectively. Otherwise
+  // we will run into fragmentation issues.
+  ifr.ifr_mtu = ETH_MTU - WG_MTU_OVERHEAD;
+  int ret = ioctl(sockfd, SIOCSIFMTU, &ifr);
+  if (ret) {
+    logger.error() << "Failed to set MTU -- Return code: " << ret;
+    return false;
+  }
+
+  // Up
+  ifr.ifr_flags |= (IFF_UP | IFF_RUNNING);
+  ret = ioctl(sockfd, SIOCSIFFLAGS, &ifr);
+  if (ret) {
+    logger.error() << "Failed to set device up -- Return code: " << ret;
+    return false;
+  }
+
+  return true;
+}
+
+bool IPUtilsLinux::addIP4AddressToDevice(const InterfaceConfig& config) {
+  struct ifreq ifr;
+  struct sockaddr_in* ifrAddr = (struct sockaddr_in*)&ifr.ifr_addr;
+
+  // Name the interface and set family
+  strncpy(ifr.ifr_name, WG_INTERFACE, IFNAMSIZ);
+  ifr.ifr_addr.sa_family = AF_INET;
+
+  // Get the device address to add to interface
+  QPair<QHostAddress, int> parsedAddr =
+      QHostAddress::parseSubnet(config.m_deviceIpv4Address);
+  QByteArray _deviceAddr = parsedAddr.first.toString().toLocal8Bit();
+  char* deviceAddr = _deviceAddr.data();
+  inet_pton(AF_INET, deviceAddr, &ifrAddr->sin_addr);
+
+  // Create IPv4 socket to perform the ioctl operations on
+  int sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
+  if (sockfd < 0) {
+    logger.error() << "Failed to create ioctl socket.";
+    return false;
+  }
+  auto guard = qScopeGuard([&] { close(sockfd); });
+
+  // Set ifr to interface
+  int ret = ioctl(sockfd, SIOCSIFADDR, &ifr);
+  if (ret) {
+    logger.error() << "Failed to set IPv4: " << logger.sensitive(deviceAddr)
+                   << "error:" << strerror(errno);
+    return false;
+  }
+  return true;
+}
+
+bool IPUtilsLinux::addIP6AddressToDevice(const InterfaceConfig& config) {
+  // Set up the ifr and the companion ifr6
+  struct in6_ifreq ifr6;
+  ifr6.prefixlen = 64;
+
+  // Get the device address to add to ifr6 interface
+  QPair<QHostAddress, int> parsedAddr =
+      QHostAddress::parseSubnet(config.m_deviceIpv6Address);
+  QByteArray _deviceAddr = parsedAddr.first.toString().toLocal8Bit();
+  char* deviceAddr = _deviceAddr.data();
+  inet_pton(AF_INET6, deviceAddr, &ifr6.addr);
+
+  // Create IPv6 socket to perform the ioctl operations on
+  int sockfd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_IP);
+  if (sockfd < 0) {
+    logger.error() << "Failed to create ioctl socket.";
+    return false;
+  }
+  auto guard = qScopeGuard([&] { close(sockfd); });
+
+  // Get the index of named ifr and link with ifr6
+  struct ifreq ifr;
+  strncpy(ifr.ifr_name, WG_INTERFACE, IFNAMSIZ);
+  ifr.ifr_addr.sa_family = AF_INET6;
+  int ret = ioctl(sockfd, SIOGIFINDEX, &ifr);
+  if (ret) {
+    logger.error() << "Failed to get ifindex. Return code: " << ret;
+    return false;
+  }
+  ifr6.ifindex = ifr.ifr_ifindex;
+
+  // Set ifr6 to the interface
+  ret = ioctl(sockfd, SIOCSIFADDR, &ifr6);
+  if (ret && (errno != EEXIST)) {
+    logger.error() << "Failed to set IPv6: " << logger.sensitive(deviceAddr)
+                   << "error:" << strerror(errno);
+    return false;
+  }
+
+  return true;
+}