/*
fd_device.c -- Interaction with Android tun fd
Copyright (C) 2001-2005 Ivo Timmermans,
- 2001-2016 Guus Sliepen <guus@tinc-vpn.org>
+ 2001-2021 Guus Sliepen <guus@tinc-vpn.org>
2009 Grzegorz Dymarek <gregd72002@googlemail.com>
- 2016
Pacien TRAN-GIRARD <pacien@pacien.net>
+ 2016
-2020 Pacien TRAN-GIRARD <pacien@pacien.net>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
*/
#include "system.h"
+
+#ifdef HAVE_SYS_UN_H
+#include <sys/un.h>
+
#include "conf.h"
#include "device.h"
#include "ethernet.h"
#include "route.h"
#include "utils.h"
-static inline bool check_config(void) {
- if(routing_mode == RMODE_SWITCH) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Switch mode not supported (requires unsupported TAP device)!");
- return false;
+struct unix_socket_addr {
+ size_t size;
+ struct sockaddr_un addr;
+};
+
+static int read_fd(int socket) {
+ char iobuf;
+ struct iovec iov = {0};
+ char cmsgbuf[CMSG_SPACE(sizeof(device_fd))];
+ struct msghdr msg = {0};
+ int ret;
+ struct cmsghdr *cmsgptr;
+
+ iov.iov_base = &iobuf;
+ iov.iov_len = 1;
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = cmsgbuf;
+ msg.msg_controllen = sizeof(cmsgbuf);
+
+ if((ret = recvmsg(socket, &msg, 0)) < 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Could not read from unix socket (error %d)!", ret);
+ return -1;
}
- if(!get_config_int(lookup_config(config_tree, "Device"), &device_fd)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Could not read fd from configuration!");
- return false;
+#ifdef IP_RECVERR
+
+ if(msg.msg_flags & (MSG_CTRUNC | MSG_OOB | MSG_ERRQUEUE)) {
+#else
+
+ if(msg.msg_flags & (MSG_CTRUNC | MSG_OOB)) {
+#endif
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error while receiving message (flags %d)!", msg.msg_flags);
+ return -1;
}
- return true;
+ cmsgptr = CMSG_FIRSTHDR(&msg);
+
+ if(cmsgptr->cmsg_level != SOL_SOCKET) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Wrong CMSG level: %d, expected %d!",
+ cmsgptr->cmsg_level, SOL_SOCKET);
+ return -1;
+ }
+
+ if(cmsgptr->cmsg_type != SCM_RIGHTS) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Wrong CMSG type: %d, expected %d!",
+ cmsgptr->cmsg_type, SCM_RIGHTS);
+ return -1;
+ }
+
+ if(cmsgptr->cmsg_len != CMSG_LEN(sizeof(device_fd))) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Wrong CMSG data length: %lu, expected %lu!",
+ (unsigned long)cmsgptr->cmsg_len, (unsigned long)CMSG_LEN(sizeof(device_fd)));
+ return -1;
+ }
+
+ return *(int *) CMSG_DATA(cmsgptr);
+}
+
+static int receive_fd(struct unix_socket_addr socket_addr) {
+ int socketfd;
+ int ret;
+ int result;
+
+ if((socketfd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Could not open stream socket (error %d)!", socketfd);
+ return -1;
+ }
+
+ if((ret = connect(socketfd, (struct sockaddr *) &socket_addr.addr, socket_addr.size)) < 0) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Could not connect to Unix socket (error %d)!", ret);
+ result = -1;
+ goto end;
+ }
+
+ result = read_fd(socketfd);
+
+end:
+ close(socketfd);
+ return result;
+}
+
+static struct unix_socket_addr parse_socket_addr(const char *path) {
+ struct sockaddr_un socket_addr = {
+ .sun_family = AF_UNIX,
+ };
+ size_t path_length;
+
+ if(strlen(path) >= sizeof(socket_addr.sun_path)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Unix socket path too long!");
+ return (struct unix_socket_addr) {
+ 0
+ };
+ }
+
+ strncpy(socket_addr.sun_path, path, sizeof(socket_addr.sun_path));
+
+ if(path[0] == '@') {
+ /* abstract namespace socket */
+ socket_addr.sun_path[0] = '\0';
+ path_length = strlen(path);
+ } else {
+ /* filesystem path with NUL terminator */
+ path_length = strlen(path) + 1;
+ }
+
+ return (struct unix_socket_addr) {
+ .size = offsetof(struct sockaddr_un, sun_path) + path_length,
+ .addr = socket_addr
+ };
}
static bool setup_device(void) {
- if(!check_config()) {
+ if(routing_mode == RMODE_SWITCH) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Switch mode not supported (requires unsupported TAP device)!");
return false;
}
+ if(!get_config_string(lookup_config(config_tree, "Device"), &device)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Could not read device from configuration!");
+ return false;
+ }
+
+ /* device is either directly a file descriptor or an unix socket to read it from */
+ if(sscanf(device, "%d", &device_fd) != 1) {
+ logger(DEBUG_ALWAYS, LOG_INFO, "Receiving fd from Unix socket at %s.", device);
+ device_fd = receive_fd(parse_socket_addr(device));
+ }
+
if(device_fd < 0) {
logger(DEBUG_ALWAYS, LOG_ERR, "Could not open %s: %s!", device, strerror(errno));
return false;
static void close_device(void) {
close(device_fd);
device_fd = -1;
+ free(iface);
+ iface = NULL;
+ free(device);
+ device = NULL;
}
static inline uint16_t get_ip_ethertype(vpn_packet_t *packet) {
.read = read_packet,
.write = write_packet,
};
+#endif
projects / tinc / blobdiff