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-rw-r--r--ggsn/tun.c490
1 files changed, 439 insertions, 51 deletions
diff --git a/ggsn/tun.c b/ggsn/tun.c
index 72ea264..5b8cc95 100644
--- a/ggsn/tun.c
+++ b/ggsn/tun.c
@@ -1,32 +1,24 @@
/*
- * OpenGGSN - Gateway GPRS Support Node
- * Copyright (C) 2002 Mondru AB.
+ * TUN interface functions.
+ * Copyright (C) 2002, 2003 Mondru AB.
*
- * The contents of this file may be used under the terms of the GNU
- * General Public License Version 2, provided that the above copyright
- * notice and this permission notice is included in all copies or
- * substantial portions of the software.
+ * The contents of this file may be used under the terms of the GNU
+ * General Public License Version 2, provided that the above copyright
+ * notice and this permission notice is included in all copies or
+ * substantial portions of the software.
*
- * The initial developer of the original code is
- * Jens Jakobsen <jj@openggsn.org>
+ * The initial developer of the original code is
+ * Jens Jakobsen <jj@openggsn.org>
*
- * Contributor(s):
+ * Contributor(s):
*
*/
/*
- * tun.c: Contains all TUN functionality. Should be able to handle multiple
- * tunnels in the same program. Each tunnel is identified by the socket.
- * I suppose that no other state information than the socket is needed.
+ * tun.c: Contains all TUN functionality. Is able to handle multiple
+ * tunnels in the same program. Each tunnel is identified by the struct,
+ * which is passed to functions.
*
- * - tun_newtun: Initialise TUN tunnel.
- * - tun_freetun: Free a device previously created with tun_newtun.
- * - tun_encaps: Encapsulate packet in TUN tunnel and send off
- * - tun_decaps: Extract packet from TUN tunnel and call function to
- * ship it off as GTP encapsulated packet.
- *
- * TODO:
- * - Do we need to handle fragmentation?
*/
@@ -54,75 +46,471 @@
#include <linux/if.h>
#include <errno.h>
#include <linux/if_tun.h>
+#include <net/route.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
#include "tun.h"
+#include "syserr.h"
+
-int tun_newtun(struct tun_t **tun)
+int tun_nlattr(struct nlmsghdr *n, int nsize, int type, void *d, int dlen)
{
+ int len = RTA_LENGTH(dlen);
+ int alen = NLMSG_ALIGN(n->nlmsg_len);
+ struct rtattr *rta = (struct rtattr*) (((void*)n) + alen);
+ if (alen + len > nsize)
+ return -1;
+ rta->rta_len = len;
+ rta->rta_type = type;
+ memcpy(RTA_DATA(rta), d, dlen);
+ n->nlmsg_len = alen + len;
+ return 0;
+}
+
+int tun_gifindex(struct tun_t *this, int *index) {
+ struct ifreq ifr;
+ int fd;
+
+ memset (&ifr, '\0', sizeof (ifr));
+ ifr.ifr_addr.sa_family = AF_INET;
+ ifr.ifr_dstaddr.sa_family = AF_INET;
+ ifr.ifr_netmask.sa_family = AF_INET;
+ strncpy(ifr.ifr_name, this->devname, IFNAMSIZ);
+ ifr.ifr_name[IFNAMSIZ-1] = 0; /* Make sure to terminate */
+ if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ }
+ if (ioctl(fd, SIOCGIFINDEX, &ifr)) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl() failed");
+ close(fd);
+ return -1;
+ }
+ close(fd);
+ *index = ifr.ifr_ifindex;
+ return 0;
+}
+
+int tun_sifflags(struct tun_t *this, int flags) {
struct ifreq ifr;
+ int fd;
+
+ memset (&ifr, '\0', sizeof (ifr));
+ ifr.ifr_flags = flags;
+ strncpy(ifr.ifr_name, this->devname, IFNAMSIZ);
+ ifr.ifr_name[IFNAMSIZ-1] = 0; /* Make sure to terminate */
+ if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ }
+ if (ioctl(fd, SIOCSIFFLAGS, &ifr)) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl(SIOCSIFFLAGS) failed");
+ close(fd);
+ return -1;
+ }
+ close(fd);
+ return 0;
+}
+
+
+/* Currently unused */
+int tun_addroute2(struct tun_t *this,
+ struct in_addr *dst,
+ struct in_addr *gateway,
+ struct in_addr *mask) {
+
+ struct {
+ struct nlmsghdr n;
+ struct rtmsg r;
+ char buf[TUN_NLBUFSIZE];
+ } req;
+
+ struct sockaddr_nl local;
+ int addr_len;
+ int fd;
+ int status;
+ struct sockaddr_nl nladdr;
+ struct iovec iov;
+ struct msghdr msg;
+
+ memset(&req, 0, sizeof(req));
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE;
+ req.n.nlmsg_type = RTM_NEWROUTE;
+ req.r.rtm_family = AF_INET;
+ req.r.rtm_table = RT_TABLE_MAIN;
+ req.r.rtm_protocol = RTPROT_BOOT;
+ req.r.rtm_scope = RT_SCOPE_UNIVERSE;
+ req.r.rtm_type = RTN_UNICAST;
+ tun_nlattr(&req.n, sizeof(req), RTA_DST, dst, 4);
+ tun_nlattr(&req.n, sizeof(req), RTA_GATEWAY, gateway, 4);
+
+ if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ return -1;
+ }
+
+ memset(&local, 0, sizeof(local));
+ local.nl_family = AF_NETLINK;
+ local.nl_groups = 0;
+
+ if (bind(fd, (struct sockaddr*)&local, sizeof(local)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "bind() failed");
+ close(fd);
+ return -1;
+ }
+
+ addr_len = sizeof(local);
+ if (getsockname(fd, (struct sockaddr*)&local, &addr_len) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "getsockname() failed");
+ close(fd);
+ return -1;
+ }
+ if (addr_len != sizeof(local)) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, 0,
+ "Wrong address length %d", addr_len);
+ close(fd);
+ return -1;
+ }
+
+ if (local.nl_family != AF_NETLINK) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, 0,
+ "Wrong address family %d", local.nl_family);
+ close(fd);
+ return -1;
+ }
+
+ iov.iov_base = (void*)&req.n;
+ iov.iov_len = req.n.nlmsg_len;
+
+ msg.msg_name = (void*)&nladdr;
+ msg.msg_namelen = sizeof(nladdr),
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_flags = 0;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = 0;
+ nladdr.nl_groups = 0;
+
+ req.n.nlmsg_seq = 0;
+ req.n.nlmsg_flags |= NLM_F_ACK;
+
+ status = sendmsg(fd, &msg, 0); /* TODO: Error check */
+ close(fd);
+ return 0;
+}
+
+
+int tun_addaddr(struct tun_t *this,
+ struct in_addr *addr,
+ struct in_addr *dstaddr,
+ struct in_addr *netmask) {
+ struct {
+ struct nlmsghdr n;
+ struct ifaddrmsg i;
+ char buf[TUN_NLBUFSIZE];
+ } req;
+
+ struct sockaddr_nl local;
+ int addr_len;
+ int fd;
+ int status;
+
+ struct sockaddr_nl nladdr;
+ struct iovec iov;
+ struct msghdr msg;
+
+ if (!this->addrs) /* Use ioctl for first addr to make ping work */
+ return tun_setaddr(this, addr, dstaddr, netmask);
+
+ memset(&req, 0, sizeof(req));
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE;
+ req.n.nlmsg_type = RTM_NEWADDR;
+ req.i.ifa_family = AF_INET;
+ req.i.ifa_prefixlen = 32; /* 32 FOR IPv4 */
+ req.i.ifa_flags = 0;
+ req.i.ifa_scope = RT_SCOPE_HOST; /* TODO or 0 */
+ if (tun_gifindex(this, &req.i.ifa_index)) {
+ return -1;
+ }
+
+ tun_nlattr(&req.n, sizeof(req), IFA_ADDRESS, addr, sizeof(addr));
+ tun_nlattr(&req.n, sizeof(req), IFA_LOCAL, dstaddr, sizeof(dstaddr));
+
+ if ((fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ return -1;
+ }
+
+ memset(&local, 0, sizeof(local));
+ local.nl_family = AF_NETLINK;
+ local.nl_groups = 0;
+
+ if (bind(fd, (struct sockaddr*)&local, sizeof(local)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "bind() failed");
+ close(fd);
+ return -1;
+ }
+
+ addr_len = sizeof(local);
+ if (getsockname(fd, (struct sockaddr*)&local, &addr_len) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "getsockname() failed");
+ close(fd);
+ return -1;
+ }
+
+ if (addr_len != sizeof(local)) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, 0,
+ "Wrong address length %d", addr_len);
+ close(fd);
+ return -1;
+ }
+
+ if (local.nl_family != AF_NETLINK) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, 0,
+ "Wrong address family %d", local.nl_family);
+ close(fd);
+ return -1;
+ }
+
+ iov.iov_base = (void*)&req.n;
+ iov.iov_len = req.n.nlmsg_len;
+
+ msg.msg_name = (void*)&nladdr;
+ msg.msg_namelen = sizeof(nladdr),
+ msg.msg_iov = &iov;
+ msg.msg_iovlen = 1;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_flags = 0;
+
+ memset(&nladdr, 0, sizeof(nladdr));
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = 0;
+ nladdr.nl_groups = 0;
+
+ req.n.nlmsg_seq = 0;
+ req.n.nlmsg_flags |= NLM_F_ACK;
+
+ status = sendmsg(fd, &msg, 0); /* TODO Error check */
+
+ tun_sifflags(this, IFF_UP | IFF_RUNNING);
+ close(fd);
+ this->addrs++;
+ return 0;
+}
+
+
+int tun_setaddr(struct tun_t *this,
+ struct in_addr *addr,
+ struct in_addr *dstaddr,
+ struct in_addr *netmask)
+{
+ struct ifreq ifr;
+ int fd;
+
+ memset (&ifr, '\0', sizeof (ifr));
+ ifr.ifr_addr.sa_family = AF_INET;
+ ifr.ifr_dstaddr.sa_family = AF_INET;
+ ifr.ifr_netmask.sa_family = AF_INET;
+ strncpy(ifr.ifr_name, this->devname, IFNAMSIZ);
+ ifr.ifr_name[IFNAMSIZ-1] = 0; /* Make sure to terminate */
+
+ /* Create a channel to the NET kernel. */
+ if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ return -1;
+ }
+
+ if (addr) { /* Set the interface address */
+ this->addr.s_addr = addr->s_addr;
+ ((struct sockaddr_in *) &ifr.ifr_addr)->sin_addr.s_addr = addr->s_addr;
+ if (ioctl(fd, SIOCSIFADDR, (void *) &ifr) < 0) {
+ if (errno != EEXIST) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl(SIOCSIFADDR) failed");
+ }
+ else {
+ sys_err(LOG_WARNING, __FILE__, __LINE__, errno,
+ "ioctl(SIOCSIFADDR): Address already exists");
+ }
+ close(fd);
+ return -1;
+ }
+ }
+
+ if (dstaddr) { /* Set the destination address */
+ this->dstaddr.s_addr = dstaddr->s_addr;
+ ((struct sockaddr_in *) &ifr.ifr_dstaddr)->sin_addr.s_addr =
+ dstaddr->s_addr;
+ if (ioctl(fd, SIOCSIFDSTADDR, (caddr_t) &ifr) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl(SIOCSIFDSTADDR) failed");
+ close(fd);
+ return -1;
+ }
+ }
+
+ if (netmask) { /* Set the netmask */
+ this->netmask.s_addr = netmask->s_addr;
+ ((struct sockaddr_in *) &ifr.ifr_netmask)->sin_addr.s_addr =
+ netmask->s_addr;
+ if (ioctl(fd, SIOCSIFNETMASK, (void *) &ifr) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl(SIOCSIFNETMASK) failed");
+ close(fd);
+ return -1;
+ }
+ }
+
+ close(fd);
+ this->addrs++;
+ return tun_sifflags(this, IFF_UP | IFF_RUNNING);
+}
+
+int tun_addroute(struct tun_t *this,
+ struct in_addr *dst,
+ struct in_addr *gateway,
+ struct in_addr *mask)
+{
+ struct rtentry r;
+ int fd;
+
+ memset (&r, '\0', sizeof (r));
+ r.rt_flags = RTF_UP | RTF_GATEWAY; /* RTF_HOST not set */
+
+ /* Create a channel to the NET kernel. */
+ if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "socket() failed");
+ return -1;
+ }
+
+ r.rt_dst.sa_family = AF_INET;
+ r.rt_gateway.sa_family = AF_INET;
+ r.rt_genmask.sa_family = AF_INET;
+ ((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr = dst->s_addr;
+ ((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr = gateway->s_addr;
+ ((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr = mask->s_addr;
+
+ if (ioctl(fd, SIOCADDRT, (void *) &r) < 0) { /* SIOCDELRT */
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno,
+ "ioctl(SIOCADDRT) failed");
+ close(fd);
+ return -1;
+ }
+ close(fd);
+ return 0;
+}
+
+
+int tun_new(struct tun_t **tun)
+{
+ struct ifreq ifr;
+
if (!(*tun = calloc(1, sizeof(struct tun_t)))) {
- syslog(LOG_ERR, "%s %d. calloc(nmemb=%d, size=%d) failed: Error = %s(%d)",
- __FILE__, __LINE__, 1, sizeof(struct tun_t),
- strerror(errno), errno);
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno, "calloc() failed");
return EOF;
}
-
+
+ (*tun)->cb_ind = NULL;
+ (*tun)->addrs = 0;
+
if (((*tun)->fd = open("/dev/net/tun", O_RDWR)) < 0) {
- syslog(LOG_ERR, "TUN: open() failed");
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno, "open() failed");
return -1;
}
-
+
memset(&ifr, 0, sizeof(ifr));
ifr.ifr_flags = IFF_TUN | IFF_NO_PI; /* Tun device, no packet info */
strncpy(ifr.ifr_name, (*tun)->devname, IFNAMSIZ);
-
+
if (ioctl((*tun)->fd, TUNSETIFF, (void *) &ifr) < 0) {
- syslog(LOG_ERR, "TUN: ioctl() failed");
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno, "ioctl() failed");
close((*tun)->fd);
return -1;
}
-
+
ioctl((*tun)->fd, TUNSETNOCSUM, 1); /* Disable checksums */
-
+
strncpy((*tun)->devname, ifr.ifr_name, IFNAMSIZ);
-
- return (*tun)->fd;
+ (*tun)->devname[IFNAMSIZ] = 0;
+
+ return 0;
}
-int tun_freetun(struct tun_t *tun)
+int tun_free(struct tun_t *tun)
{
if (close(tun->fd)) {
- syslog(LOG_ERR, "%s %d. close(fd=%d) failed: Error = %s",
- __FILE__, __LINE__, tun->fd, strerror(errno));
- return EOF;
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno, "close() failed");
}
+
free(tun);
return 0;
}
-int tun_decaps(struct tun_t *tun,
- int (*cb) (void *cl, struct tun_t*, void *pack, unsigned len),
- void *cl)
-{
- unsigned char buffer[PACKET_MAX + 64 /*TODO: ip header */ ];
- int status;
+int tun_set_cb_ind(struct tun_t *this,
+ int (*cb_ind) (struct tun_t *tun, void *pack, unsigned len)) {
+ this->cb_ind = cb_ind;
+ return 0;
+}
- if ((status = read(tun->fd, buffer, sizeof(buffer))) <= 0) {
- syslog(LOG_ERR, "TUN: read(fd=%d,buffer=%lx,len=%d) from network failed: status = %d error = %s",
- tun->fd, (unsigned long) buffer, sizeof(buffer), status, status ? strerror(errno) : "No error");
- return -1;
- }
+int tun_decaps(struct tun_t *this)
+{
+ unsigned char buffer[PACKET_MAX];
+ int status;
+
+ if ((status = read(this->fd, buffer, sizeof(buffer))) <= 0) {
+ sys_err(LOG_ERR, __FILE__, __LINE__, errno, "read() failed");
+ return -1;
+ }
+
+ if (this->cb_ind)
+ return this->cb_ind(this, buffer, status);
- /* Need to include code to verify packet src and dest addresses */
- return cb(cl, tun, buffer, status);
+ return 0;
}
int tun_encaps(struct tun_t *tun, void *pack, unsigned len)
{
- return write(tun->fd, pack, len);
+ return write(tun->fd, pack, len);
+}
+
+int tun_runscript(struct tun_t *tun, char* script) {
+
+ char buf[TUN_SCRIPTSIZE];
+ char snet[TUN_ADDRSIZE];
+ char smask[TUN_ADDRSIZE];
+
+ strncpy(snet, inet_ntoa(tun->addr), sizeof(snet));
+ snet[sizeof(snet)-1] = 0;
+ strncpy(smask, inet_ntoa(tun->netmask), sizeof(smask));
+ smask[sizeof(smask)-1] = 0;
+
+ /* system("ipup /dev/tun0 192.168.0.10 255.255.255.0"); */
+ snprintf(buf, sizeof(buf), "%s %s %s %s",
+ script, tun->devname, snet, smask);
+ buf[sizeof(buf)-1] = 0;
+ system(buf);
+ return 0;
}
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