added ippool.h and ippool.c
diff --git a/sgsnemu/tun.c b/sgsnemu/tun.c
index 72ea264..5b8cc95 100644
--- a/sgsnemu/tun.c
+++ b/sgsnemu/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;
 
-  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);
-    return EOF;
+  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;
+}
 
-  if (((*tun)->fd  = open("/dev/net/tun", O_RDWR)) < 0) {
-    syslog(LOG_ERR, "TUN: open() failed");
+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)))) {
+    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) {
+    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)
+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;
+}
+
+
+int tun_decaps(struct tun_t *this)
 {
-	unsigned char buffer[PACKET_MAX + 64 /*TODO: ip header */ ];
-	int status;
+  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);
 
-
-	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;
-	}
-
-	/* 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;
 }