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iouyap.c
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iouyap.c
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/*
* This file is part of iouyap, a program to bridge IOU with
* network interfaces.
*
* Copyright (C) 2013, 2014 James E. Carpenter
*
* iouyap 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 of the License, or
* (at your option) any later version.
*
* iouyap 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <pthread.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <arpa/inet.h>
#include <netpacket/packet.h>
#include <net/ethernet.h>
#include <netdb.h>
#include <net/if_arp.h>
#include <linux/rtnetlink.h>
#include <linux/netlink.h>
#include <sys/time.h>
#include <limits.h>
#include <sys/file.h>
#include <ctype.h>
#include "iouyap.h"
#include "iniparser/iniparser.h"
#include "netmap.h"
#include "config.h"
extern char *program_invocation_short_name;
extern char *program_invocation_name;
int yap_appl_id = -1;
unsigned int yap_verbose = LOG_BASIC;
dictionary *yap_config = NULL;
foreign_port_t *port_table = NULL;
static int
set_socket_directory (char *dir)
{
return snprintf (dir, UNIX_PATH_MAX, "%s%u", NETIO_DIR_PREFIX, getuid ());
}
static int
set_socket_filename (char *name, unsigned int appl_id)
{
char dir[UNIX_PATH_MAX];
set_socket_directory (dir);
return snprintf (name, UNIX_PATH_MAX, "%s/%u", dir, appl_id);
}
static pid_t
get_socket_lock (const char *name)
{
char semaphore[FILENAME_MAX];
int fd;
struct flock fl;
int e;
if (strlen (name) < 1)
{
errno = EINVAL;
return -1;
}
snprintf (semaphore, sizeof semaphore, "%s.lck", name);
if ((fd = open (semaphore, O_RDONLY)) < 0)
return -1;
fl.l_type = F_WRLCK;
fl.l_whence = SEEK_SET;
fl.l_start = 0;
fl.l_len = 0;
fl.l_pid = getpid ();
if (fcntl (fd, F_GETLK, &fl) < 0)
{
e = errno;
close (fd);
errno = e;
return -1;
}
close (fd);
return fl.l_pid;
}
static int
unlock_socket (int fd, const char *name)
{
char semaphore[FILENAME_MAX];
int result;
int e;
if (fd < 0)
{
errno = EINVAL;
return -1;
}
snprintf (semaphore, sizeof semaphore, "%s.lck", name);
/* Unlinking before close avoids a race condition where we
* could accidentally delete the next lock file.
*/
result = unlink (semaphore);
e = errno;
close (fd);
errno = e;
return result;
}
static int
lock_socket (const char *name)
{
char semaphore[FILENAME_MAX];
int fd;
char pid[12];
int pid_len;
struct flock fl;
int e;
if (strlen (name) < 1)
{
errno = EINVAL;
return -1;
}
snprintf (semaphore, sizeof semaphore, "%s.lck", name);
// Either find a lock-file or create a new one
if ((fd = open (semaphore, O_WRONLY)) < 0 && errno == ENOENT)
fd = open (semaphore, O_CREAT | O_EXCL | O_WRONLY, S_IRUSR | S_IWUSR);
if (fd < 0)
return -1;
fl.l_type = F_WRLCK;
fl.l_whence = SEEK_SET;
fl.l_start = 0;
fl.l_len = 0;
if (fcntl (fd, F_SETLK, &fl) < 0)
{
close (fd);
errno = EADDRINUSE;
return -1;
}
// We have the lock. Wipe out the file and put our PID in it.
ftruncate (fd, 0);
pid_len = snprintf (pid, sizeof(pid), "%ld\n", (long) getpid ());
if (write (fd, pid, pid_len) == -1)
{
e = errno;
// Something is wrong. Roll back.
unlock_socket (fd, name);
errno = e;
return -1;
}
return fd;
}
/* getbits: get n bits from position p
* (liberated from K&R2, p. 49)
*/
static unsigned int
getbits (unsigned int x, int p, int n)
{
return (x >> (p + 1 - n)) & ~(~0 << n);
}
static unsigned int
setbits (unsigned int x, int p, int n, unsigned int y)
{
return ((x & ~(~(~0 << n) << (p + 1 - n)))
| ((y & ~(~0 << n)) << (p + 1 - n)));
}
appl_id_t
unpack_ids (unsigned short appl_id)
{
appl_id_t i;
i.id = getbits(appl_id, IOU_IDS_ID, IOU_IDS_ID_LEN);
i.subid = getbits(appl_id, IOU_IDS_SUBID, IOU_IDS_SUBID_LEN);
i.subid_present = getbits(appl_id, IOU_IDS_SUBID_PRESENT,
IOU_IDS_SUBID_PRESENT_LEN);
return i;
}
port_t
unpack_port (unsigned char port)
{
port_t p;
p.unit = getbits(port, IOU_PORT_UNIT, IOU_PORT_UNIT_LEN);
p.bay = getbits(port, IOU_PORT_BAY, IOU_PORT_BAY_LEN);
return p;
}
unsigned short
pack_ids (appl_id_t appl_id)
{
unsigned short i = 0;
i = setbits (i, IOU_IDS_ID, IOU_IDS_ID_LEN, appl_id.id);
i = setbits (i, IOU_IDS_SUBID, IOU_IDS_SUBID_LEN, appl_id.subid);
i = setbits (i, IOU_IDS_SUBID_PRESENT, IOU_IDS_SUBID_PRESENT_LEN,
appl_id.subid_present);
return i;
}
unsigned char
pack_port (port_t port)
{
unsigned char p = 0;
p = setbits (p, IOU_PORT_BAY, IOU_PORT_BAY_LEN, port.bay);
p = setbits (p, IOU_PORT_UNIT, IOU_PORT_UNIT_LEN, port.unit);
return p;
}
void
parse_iou_hdr (iou_hdr_t *iou_hdr, unsigned char *iou_hdr_buf)
{
unsigned short dst_node;
unsigned short src_node;
unsigned char dst_port;
unsigned char src_port;
/* destination node */
dst_node = ntohs (*(unsigned short *) &iou_hdr_buf[IOU_DST_IDS]);
iou_hdr->dst_node.ids = unpack_ids (dst_node);
/* source node */
src_node = ntohs (*(unsigned short *) &iou_hdr_buf[IOU_SRC_IDS]);
iou_hdr->src_node.ids = unpack_ids (src_node);
/* destination port */
dst_port = iou_hdr_buf[IOU_DST_PORT];
iou_hdr->dst_node.port = unpack_port (dst_port);
/* source port */
src_port = iou_hdr_buf[IOU_SRC_PORT];
iou_hdr->src_node.port = unpack_port (src_port);
/* message type & channel */
iou_hdr->msg_type = iou_hdr_buf[IOU_MSG_TYPE];
iou_hdr->channel = iou_hdr_buf[IOU_CHANNEL];
}
void
build_iou_hdr (unsigned char *buf, iou_hdr_t iou_hdr)
{
appl_id_t dst_ids = iou_hdr.dst_node.ids;
appl_id_t src_ids = iou_hdr.src_node.ids;
port_t dst_port = iou_hdr.dst_node.port;
port_t src_port = iou_hdr.src_node.port;
unsigned short n;
/* destination id */
n = htons (pack_ids (dst_ids));
memcpy(&buf[IOU_DST_IDS], (unsigned char *)&n, IOU_IDS_SIZE);
/* source id */
n = htons (pack_ids (src_ids));
memcpy(&buf[IOU_SRC_IDS], (unsigned char *)&n, IOU_IDS_SIZE);
/* destination port */
buf[IOU_DST_PORT] = pack_port (dst_port);
/* source port */
buf[IOU_SRC_PORT] = pack_port (src_port);
/* message type */
buf[IOU_MSG_TYPE] = iou_hdr.msg_type;
/* channel number */
buf[IOU_CHANNEL] = iou_hdr.channel;
}
static int
get_iou_udp_port (int port)
{
return ini_getint_default_def ("base_port", BASE_PORT) + port;
}
static int
write_pcap_header (int fd, int snaplen, int linktype)
{
struct pcap_file_header header;
header.magic = 0xa1b2c3d4;
header.version_major = 2;
header.version_minor = 4;
header.thiszone = 0;
header.sigfigs = 0;
header.snaplen = snaplen;
header.linktype = linktype;
if (write (fd, &header, sizeof header) != sizeof header)
return -1;
return 0;
}
static int
write_pcap_frame (int fd, const unsigned char *packet, size_t len,
size_t caplen, int linktype)
{
size_t count;
struct pcap_pkthdr pcap_header;
size_t hdr_len = sizeof pcap_header;
unsigned char buf[MAX_MTU + hdr_len];
struct timeval ts;
if (caplen > MAX_MTU)
return -1;
gettimeofday (&ts, 0);
pcap_header.tv_sec = ts.tv_sec;
pcap_header.tv_usec = ts.tv_usec;
if (len < caplen)
caplen = len;
pcap_header.caplen = caplen;
pcap_header.len = len;
memcpy (buf, &pcap_header, hdr_len);
memcpy (&buf[hdr_len], packet, caplen);
count = caplen + hdr_len;
if (write (fd, &buf, count) != count)
return -1;
return 0;
}
static void *
foreign_listener (void *arg)
{
foreign_port_t *port = arg;
int segment_size;
ssize_t bytes_received, bytes_sent;
iou_node_t *nodes;
unsigned char buf[IOU_HDR_SIZE + MAX_MTU]; // TODO: may already include HDR
int i, j;
/* segment size, minus us */
segment_size = port->segment->size - 1;
nodes = port->nodes;
if (yap_verbose >= LOG_EXTENDED)
log_fmt ("foreign listener for %d:%d started (sfd=%d)\n",
yap_appl_id, port->iou_port, port->sfd);
for (;;)
{
/* Put received bytes after the (absent) IOU header */
bytes_received = read (port->sfd, &buf[IOU_HDR_SIZE], MAX_MTU);
if (bytes_received <= 0)
{
/* When tunneling, because our sends are asynchronous, we
* can get errors here from ICMP packets for UDP packets we
* sent earlier.
*/
switch (errno)
{
case ECONNREFUSED:
if (yap_verbose >= LOG_NOISY)
log_error ("read");
continue;
default:
log_error ("read");
goto shutdown;
}
}
if (yap_verbose >= LOG_CRAZY)
debug_log_fmt ("received %zd bytes (sfd=%d)\n",
bytes_received, port->sfd);
if (port->span_sfd != NO_FD)
write (port->span_sfd, &buf[IOU_HDR_SIZE], bytes_received);
if (port->pcap_fd != NO_FD)
{
write_pcap_frame (port->pcap_fd, &buf[IOU_HDR_SIZE],
bytes_received, port->pcap_caplen,
port->pcap_linktype);
}
/* Add the length of the IOU header we'll be sending */
bytes_received += IOU_HDR_SIZE;
/* Send the packet to the IOU node(s) in our segment. For each
* node, we copy the pre-calculated IOU header into the
* beginning of the buffer before sending.
*/
for (i = 0; i < segment_size; i++)
{
memcpy (buf, &nodes[i].header, sizeof nodes[i].header);
bytes_sent = sendto (nodes[i].sfd, buf, bytes_received,
0, &nodes[i].sa, nodes[i].sa_len);
/* Make sure everything went out. Certain errors, like a
* socket that hasn't been created yet, should be ignored.
* Others we can consider fatal and so we remove the node
* from the IOU segment.
*/
if (bytes_sent != bytes_received)
{
if (bytes_sent != -1) /* no error, shouldn't happen */
{
log_fmt ("sendto() only sent %zd of %zd bytes!"
" (sfd=%d)\n", bytes_sent,
bytes_received, port->sfd);
continue;
}
switch (errno)
{
case ENOENT: /* Socket file doesn't exist */
case ECONNREFUSED:
if (yap_verbose >= LOG_NOISY)
log_error ("sendto");
continue;
default:
log_error ("sendto");
break;
}
/* Remove the offending node */
segment_size--;
for (j = i; j < segment_size; j++)
nodes[j] = nodes[j + 1];
i--; /* redo (now with the next node) */
log_msg ("offending node removed");
if (segment_size == 0)
{
log_msg ("no nodes left!");
goto shutdown;
}
}
}
}
shutdown:
log_msg ("Thread shutting down because of errors");
return NULL;
}
static void *
iou_listener (void *arg)
{
int sfd = *(int *) arg;
ssize_t bytes_received, bytes_sent;
unsigned char buf[IOU_HDR_SIZE + MAX_MTU]; // TODO: may already include HDR
unsigned int port;
#ifdef DEBUG
iou_hdr_t iou_hdr;
#endif
if (yap_verbose >= LOG_EXTENDED)
log_fmt ("IOU listener for ID %d started (sfd=%d)\n", yap_appl_id, sfd);
for (;;)
{
/* This receives from an IOU instance */
bytes_received = read (sfd, buf, IOU_HDR_SIZE + MAX_MTU);
if (bytes_received <= 0)
{
log_error ("read");
break;
}
#ifdef DEBUG
parse_iou_hdr (&iou_hdr, buf);
if (iou_hdr.dst_node.ids.id != yap_appl_id
|| iou_hdr.dst_node.ids.subid_present == 1)
{
log_msg ("Packet is not for us!");
continue;
}
#endif
/* Get the port number we were addressed as */
port = buf[IOU_DST_PORT];
if (yap_verbose >= LOG_CRAZY)
debug_log_fmt ("received %zd bytes for port %d (sfd=%d)\n",
bytes_received, port, sfd);
if (bytes_received <= IOU_HDR_SIZE)
continue;
/* Send on the packet, minus the IOU header */
bytes_received -= IOU_HDR_SIZE;
if (port_table[port].span_sfd != NO_FD)
write (port_table[port].span_sfd, &buf[IOU_HDR_SIZE],
bytes_received);
if (port_table[port].pcap_fd != NO_FD)
{
write_pcap_frame (port_table[port].pcap_fd, &buf[IOU_HDR_SIZE],
bytes_received, port_table[port].pcap_caplen,
port_table[port].pcap_linktype);
}
bytes_sent = write (port_table[port].sfd, &buf[IOU_HDR_SIZE],
bytes_received);
if (bytes_sent != bytes_received)
{
if (bytes_sent != -1) /* no error, shouldn't happen */
{
log_fmt ("write() only sent %zd of %zd bytes! (sfd=%d)\n",
bytes_sent, bytes_received, sfd);
continue;
}
switch (errno)
{
// case ENOENT:
// if (yap_verbose >= LOG_NOISY)
// log_msg ("ENOENT");
// continue;
case EBADF: /* Bad file descriptor */
/* This error is normal if no foreign port is configured */
if (port_table[port].sfd == NO_FD)
{
if (yap_verbose >= LOG_NOISY)
log_fmt ("Discarding packet from port %d. "
"No foreign port configured.\n", port);
continue;
}
break;
case ECONNREFUSED:
if (yap_verbose >= LOG_NOISY)
log_msg ("ECONNREFUSED");
continue;
case ENOTCONN:
if (yap_verbose >= LOG_NOISY)
log_msg ("ENOTCONN");
/* Try to (re-)connect */
if (!connect (port_table[port].sfd, &port_table[port].sa,
port_table[port].sa_len))
continue;
/* We couldn't connect. Some connect errors are okay.
We'll just try again later. */
switch (errno)
{
case ENOENT:
case ECONNREFUSED:
continue;
default:
log_error ("connect");
goto shutdown;
}
break;
default:
break;
}
log_error ("Couldn't write to foreign port");
goto shutdown;
}
}
shutdown:
log_msg ("Thread shutting down because of errors");
return NULL;
}
static void
open_eth_dev (foreign_port_t * port, char *dev)
{
int sfd;
struct ifreq ifr;
struct sockaddr_ll sa;
struct packet_mreq mreq;
if (strlen (dev) >= IFNAMSIZ)
die ("too big");
if (yap_verbose >= LOG_EXTENDED)
log_fmt ("Trying to open %s\n", dev);
/* open socket */
sfd = socket (AF_PACKET, SOCK_RAW, htons (ETH_P_ALL));
if (sfd == -1)
fatal_error ("socket");
/* get interface number */
memset (&ifr, 0, sizeof ifr);
strcpy (ifr.ifr_name, dev);
if (ioctl (sfd, SIOCGIFINDEX, &ifr) == -1)
fatal_error ("ioctl");
if (yap_verbose >= LOG_NOISY)
log_fmt ("ifr_name=%s, ifr_ifindex=%d\n", ifr.ifr_name, ifr.ifr_ifindex);
/* bind */
memset (&sa, 0, sizeof sa);
sa.sll_family = AF_PACKET;
sa.sll_ifindex = ifr.ifr_ifindex;
if (bind (sfd, (struct sockaddr *) &sa, sizeof sa) == -1)
fatal_error ("bind");
/* set promiscuous mode */
memset (&mreq, 0, sizeof mreq);
mreq.mr_ifindex = ifr.ifr_ifindex;
mreq.mr_type = PACKET_MR_PROMISC;
if (setsockopt (sfd, SOL_PACKET, PACKET_ADD_MEMBERSHIP,
&mreq, sizeof mreq) == -1)
fatal_error ("setsockopt");
if (yap_verbose >= LOG_BASIC)
log_fmt ("%s opened (sfd=%d)\n", ifr.ifr_name, sfd);
port->sfd = sfd;
}
static void
open_tap_dev (foreign_port_t * port, char *dev)
{
struct ifreq ifr;
int sfd;
if (strlen (dev) >= IFNAMSIZ)
die ("too big");
if (yap_verbose >= LOG_EXTENDED)
log_fmt ("Trying to open %s\n", dev);
if ((sfd = open (TAP_DEV, O_RDWR)) < 0)
fatal_error ("open");
memset (&ifr, 0, sizeof ifr);
ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
if (*dev)
strcpy (ifr.ifr_name, dev);
if (ioctl (sfd, TUNSETIFF, (void *) &ifr) < 0)
fatal_error ("ioctl");
strcpy (dev, ifr.ifr_name);
if (yap_verbose >= LOG_BASIC)
log_fmt ("%s opened (sfd=%d)\n", ifr.ifr_name, sfd);
port->sfd = sfd;
}
static void
open_span_dev (foreign_port_t * port, char *dev)
{
struct ifreq ifr;
int sfd;
int sock;
struct {
struct nlmsghdr nh;
struct ifinfomsg ifinfo;
char attrbuf[512];
} req;
struct rtattr *rta;
unsigned int mtu = 68; // too small for IPv6, which is good here
int rtnetlink_sk;
if (strlen (dev) >= IFNAMSIZ)
die ("too big");
if (yap_verbose >= LOG_EXTENDED)
log_fmt ("Trying to open %s\n", dev);
if ((sfd = open (TAP_DEV, O_WRONLY)) < 0)
fatal_error ("open");
memset (&ifr, 0, sizeof ifr);
ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_MULTI_QUEUE;
if (*dev)
strcpy (ifr.ifr_name, dev);
if (ioctl (sfd, TUNSETIFF, (void *) &ifr) < 0)
fatal_error ("TUNSETIFF ioctl");
if (yap_verbose >= LOG_BASIC)
log_fmt ("%s opened (sfd=%d)\n", ifr.ifr_name, sfd);
sock = socket(AF_INET, SOCK_DGRAM, 0);
if (ioctl (sock, SIOCGIFINDEX, (void *) &ifr) < 0)
fatal_error ("SIOCGIFINDEX ioctl");
rtnetlink_sk = socket (AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
memset (&req, 0, sizeof req);
req.nh.nlmsg_len = NLMSG_LENGTH (sizeof req.ifinfo);
req.nh.nlmsg_flags = NLM_F_REQUEST;
req.nh.nlmsg_type = RTM_SETLINK;
req.ifinfo.ifi_family = AF_UNSPEC;
req.ifinfo.ifi_index = ifr.ifr_ifindex;
req.ifinfo.ifi_change = 0xffffffff;
req.ifinfo.ifi_flags = IFF_UP | IFF_PROMISC | IFF_NOARP;
rta = (struct rtattr *)(((char *) &req) + NLMSG_ALIGN (req.nh.nlmsg_len));
rta->rta_type = IFLA_MTU;
rta->rta_len = RTA_LENGTH (sizeof (unsigned int));
req.nh.nlmsg_len = NLMSG_ALIGN (req.nh.nlmsg_len) + RTA_LENGTH (sizeof mtu);
memcpy (RTA_DATA (rta), &mtu, sizeof mtu);
send (rtnetlink_sk, &req, req.nh.nlmsg_len, 0);
close (rtnetlink_sk);
port->span_sfd = sfd;
}
static void
open_pcap_file (foreign_port_t * port, char *file, int no_hdr, int overwrite)
{
int fd;
if ((fd = open (file, O_CREAT | O_WRONLY | O_APPEND, S_IRUSR | S_IWUSR)) < 0)
fatal_error ("open");
if( getuid() != geteuid() )
if( fchown(fd, getuid (), -1) )
fatal_error ("fchown");
/* If we can get an exclusive lock (without blocking) then check to see
* if the file is empty. Write a pcap header if it is.
*/
if (!no_hdr || overwrite)
{
if (flock (fd, LOCK_EX | LOCK_NB) == 0)
{
if (overwrite)
ftruncate (fd, 0);
if (!no_hdr && lseek (fd, 0, SEEK_END) == 0)
{
if (write_pcap_header (fd, port->pcap_caplen,
port->pcap_linktype) < 0)
{
fatal_error ("write_pcap_header");
}
}
}
else if (errno == EWOULDBLOCK)
{
if (overwrite)
log_fmt ("Can't overwrite %s. Somebody has a lock.\n", file);
}
else
{
close (fd);
fatal_error ("flock");
}
}
/* For normal operation we hold a shared lock */
if (flock (fd, LOCK_SH) < 0)
{
close (fd);
fatal_error ("flock");
}
port->pcap_fd = fd;
}
static void
open_pcap_pipe (foreign_port_t * port, char *file, int no_hdr)
{
int fd;
int new_pipe = 0;
/* Create the named pipe. Whoever creates it has to clean up. */
if (mkfifo (file, S_IRUSR | S_IWUSR) == 0)
{
port->pcap_fifo = file;
new_pipe = 1;
}
else if (errno != EEXIST)
{
fatal_error ("mkfifo");
}
// O_RDWR allows us to open the pipe without any readers attached
if ((fd = open (file, O_RDWR)) < 0)
{
fatal_error ("open");
}
/* If we created the pipe then we should normally be the one to write the
* header.
*/
if (!no_hdr && new_pipe)
{
if (flock (fd, LOCK_EX | LOCK_NB) == 0)
{
if (write_pcap_header (fd, port->pcap_caplen,
port->pcap_linktype) < 0)
{
fatal_error ("write_pcap_header");
}
}
else if (errno == EWOULDBLOCK)
{
log_msg ("Couldn't write pcap header to pipe we created! Locked.");
}
else
{
close (fd);
fatal_error ("flock");
}
}
/* For normal operation we hold a shared lock */
if (flock (fd, LOCK_SH) < 0)
{
close (fd);
fatal_error ("flock");
}
port->pcap_fd = fd;
}
static void
open_tunnel_uds (foreign_port_t * port, char *socks)
{
char *local_sock;
char *remote_sock;
struct sockaddr_un sock_addr;
// TODO: validate!
local_sock = strtok (socks, ":");
remote_sock = strtok (NULL, ":");
if (yap_verbose >= LOG_EXTENDED)
{
log_fmt ("binding to %s\n", local_sock);
log_fmt ("connecting to %s\n", remote_sock);
}
if ((port->sfd = socket (AF_UNIX, SOCK_DGRAM, 0)) < 0)
fatal_error ("socket");
/* bind */
memset (&sock_addr, 0, sizeof sock_addr);
sock_addr.sun_family = AF_UNIX;
strcpy (sock_addr.sun_path, local_sock);
unlink (sock_addr.sun_path);
if (bind (port->sfd, (struct sockaddr *) &sock_addr, sizeof sock_addr))
fatal_error ("bind");
/* save it so we can clean it up later */
port->socket_fname = local_sock;
/* connect */
port->sa_len = sizeof port->sa_un;
memset (&port->sa_un, 0, port->sa_len);
port->sa_un.sun_family = AF_UNIX;
strcpy (port->sa_un.sun_path, remote_sock);
/* We'll *try* to connect now. */
if (connect (port->sfd, &port->sa, port->sa_len) == -1)
{
/* Some connect errors are okay. We'll just try again later. */
switch (errno)
{
case ENOENT:
case ECONNREFUSED:
break;
default:
fatal_error ("connect");
}
}
}
static void
open_tunnel_udp (foreign_port_t * port, char *ports)
{
char *local_port;
char *remote_host;
char *remote_port;
int sfd;
struct addrinfo hints;
struct addrinfo *result, *rp;
int yes = 1;
// TODO: validate data
local_port = strtok (ports, ":");
remote_host = strtok (NULL, ":");
remote_port = strtok (NULL, ":");
if (yap_verbose >= LOG_EXTENDED)
{
log_fmt ("binding to UDP port %s\n", local_port);
log_fmt ("connecting to UDP %s:%s\n", remote_host, remote_port);
}
/* bind */
memset (&hints, 0, sizeof hints);
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_DGRAM;
hints.ai_flags = AI_PASSIVE;
hints.ai_protocol = 0;
hints.ai_canonname = NULL;
hints.ai_addr = NULL;
hints.ai_next = NULL;
// TODO: allow binding to a specific IP address
if (getaddrinfo (NULL, local_port, &hints, &result) != 0)
fatal_error ("getaddrinfo");
for (rp = result; rp != NULL; rp = rp->ai_next)
{
sfd = socket (rp->ai_family, rp->ai_socktype, rp->ai_protocol);
if (sfd == -1)
continue;
setsockopt(sfd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof yes);
if (bind (sfd, rp->ai_addr, rp->ai_addrlen) == 0)
break;
close (sfd);
}
if (rp == NULL)
die ("Could not bind");
freeaddrinfo (result);
/* connect */
memset (&hints, 0, sizeof hints);
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_DGRAM;
hints.ai_flags = 0;
hints.ai_protocol = 0;
if (getaddrinfo (remote_host, remote_port, &hints, &result) != 0)
fatal_error ("getaddrinfo");