X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet.c;h=dd692e8e547e357e52ea073f273f88ca5a43565d;hp=e62bb8dc122b519097a0d1cac913fff312d31aec;hb=afc05797077641baa33b024ffeaafd6cad3ff7a7;hpb=cea3d8f3056d3c6aaaef473443240b8470c8ea2d

diff --git a/src/net.c b/src/net.c
index e62bb8dc..dd692e8e 100644
--- a/src/net.c
+++ b/src/net.c
@@ -17,7 +17,7 @@
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 
-    $Id: net.c,v 1.35.4.54 2000/10/29 10:39:06 guus Exp $
+    $Id: net.c,v 1.35.4.66 2000/11/04 20:44:26 guus Exp $
 */
 
 #include "config.h"
@@ -51,11 +51,11 @@
 #include <xalloc.h>
 
 #include "conf.h"
+#include "connlist.h"
+#include "meta.h"
 #include "net.h"
 #include "netutl.h"
 #include "protocol.h"
-#include "meta.h"
-#include "connlist.h"
 #include "subnet.h"
 
 #include "system.h"
@@ -74,33 +74,64 @@ int keylifetime = 0;
 int keyexpires = 0;
 
 char *unknown = NULL;
+char *interface_name = NULL;  /* Contains the name of the interface */
 
 subnet_t mymac;
 
 /*
-  strip off the MAC adresses of an ethernet frame
+  Execute the given script.
+  This function doesn't really belong here.
 */
-void strip_mac_addresses(vpn_packet_t *p)
+int execute_script(const char* name)
 {
-cp
-  memmove(p->data, p->data + 12, p->len -= 12);
-cp
-}
+  char *scriptname;
+  pid_t pid;
+  char *s;
 
-/*
-  reassemble MAC addresses
-*/
-void add_mac_addresses(vpn_packet_t *p)
-{
-cp
-  memcpy(p->data + 12, p->data, p->len);
-  p->len += 12;
-  p->data[0] = p->data[6] = 0xfe;
-  p->data[1] = p->data[7] = 0xfd;
-  /* Really evil pointer stuff just below! */
-  *((ip_t*)(&p->data[2])) = (ip_t)(htonl(myself->address));
-  *((ip_t*)(&p->data[8])) = *((ip_t*)(&p->data[26]));
-cp
+  if((pid = fork()) < 0)
+    {
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "fork");
+      return -1;
+    }
+
+  if(pid)
+    {
+      return 0;
+    }
+
+  /* Child here */
+
+  asprintf(&scriptname, "%s/%s", confbase, name);
+  asprintf(&s, "IFNAME=%s", interface_name);
+  putenv(s);
+  free(s);
+
+  if(netname)
+    {
+      asprintf(&s, "NETNAME=%s", netname);
+      putenv(s);
+      free(s);
+    }
+  else
+    {
+      unsetenv("NETNAME");
+    }
+
+  if(chdir(confbase) < 0)
+    {
+      syslog(LOG_ERR, _("Couldn't chdir to `%s': %m"),
+	     confbase);
+    }
+  
+  execl(scriptname, NULL);
+  /* No return on success */
+  
+  if(errno != ENOENT)  /* Ignore if the file does not exist */
+    syslog(LOG_WARNING, _("Error executing `%s': %m"), scriptname);
+
+  /* No need to free things */
+  exit(0);
 }
 
 int xsend(conn_list_t *cl, vpn_packet_t *inpkt)
@@ -111,7 +142,9 @@ int xsend(conn_list_t *cl, vpn_packet_t *inpkt)
 cp
   outpkt.len = inpkt->len;
   
-  EVP_EncryptInit(&ctx, cl->cipher_pkttype, cl->cipher_pktkey, cl->cipher_pktkey);
+  /* Encrypt the packet */
+  
+  EVP_EncryptInit(&ctx, cl->cipher_pkttype, cl->cipher_pktkey, cl->cipher_pktkey + cl->cipher_pkttype->key_len);
   EVP_EncryptUpdate(&ctx, outpkt.data, &outlen, inpkt->data, inpkt->len);
   EVP_EncryptFinal(&ctx, outpkt.data + outlen, &outpad);
   outlen += outpad + 2;
@@ -127,8 +160,6 @@ cp
 
   total_socket_out += outlen;
 
-  cl->want_ping = 1;
-
   if((send(cl->socket, (char *) &(outpkt.len), outlen, 0)) < 0)
     {
       syslog(LOG_ERR, _("Error sending packet to %s (%s): %m"),
@@ -146,8 +177,11 @@ int xrecv(vpn_packet_t *inpkt)
   EVP_CIPHER_CTX ctx;
 cp
   outpkt.len = inpkt->len;
-  EVP_DecryptInit(&ctx, myself->cipher_pkttype, myself->cipher_pktkey, NULL);
-  EVP_DecryptUpdate(&ctx, outpkt.data, &outlen, inpkt->data, inpkt->len);
+
+  /* Decrypt the packet */
+
+  EVP_DecryptInit(&ctx, myself->cipher_pkttype, myself->cipher_pktkey, myself->cipher_pktkey + myself->cipher_pkttype->key_len);
+  EVP_DecryptUpdate(&ctx, outpkt.data, &outlen, inpkt->data, inpkt->len + 8);
   EVP_DecryptFinal(&ctx, outpkt.data + outlen, &outpad);
   outlen += outpad;
 
@@ -156,6 +190,10 @@ cp
   memcpy(&outpkt, inpkt, outlen);
 */
      
+  if(debug_lvl >= DEBUG_TRAFFIC)
+    syslog(LOG_ERR, _("Writing packet of %d bytes to tap device"),
+           outpkt.len, outlen);
+
   /* Fix mac address */
 
   memcpy(outpkt.data, mymac.net.mac.address.x, 6);
@@ -318,10 +356,21 @@ cp
         }
 
       return -1;
-   }
+    }
 
   cl = subnet->owner;
     
+  if(cl == myself)
+    {
+      if(debug_lvl >= DEBUG_TRAFFIC)
+        {
+          syslog(LOG_NOTICE, _("Packet with destination %d.%d.%d.%d is looping back to us!"),
+	         IP_ADDR_V(to));
+        }
+
+      return -1;
+    }
+
   /* If we ourselves have indirectdata flag set, we should send only to our uplink! */
 
   /* FIXME - check for indirection and reprogram it The Right Way(tm) this time. */
@@ -371,7 +420,6 @@ int setup_tap_fd(void)
   int nfd;
   const char *tapfname;
   config_t const *cfg;
-  char *envvar;
   struct ifreq ifr;
 
 cp  
@@ -421,9 +469,8 @@ cp
   /* Add name of network interface to environment (for scripts) */
 
   ioctl(tap_fd, SIOCGIFNAME, (void *) &ifr);
-  asprintf(&envvar, "IFNAME=%s", ifr.ifr_name);
-  putenv(envvar);
-  free(envvar);
+  interface_name = xmalloc(strlen(ifr.ifr_name));
+  strcpy(interface_name, ifr.ifr_name);
   
 cp
   return 0;
@@ -448,20 +495,23 @@ cp
 
   if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)))
     {
-      syslog(LOG_ERR, _("setsockopt: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "setsockopt");
       return -1;
     }
 
   if(setsockopt(nfd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one)))
     {
-      syslog(LOG_ERR, _("setsockopt: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "setsockopt");
       return -1;
     }
 
   flags = fcntl(nfd, F_GETFL);
   if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
     {
-      syslog(LOG_ERR, _("fcntl: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "fcntl");
       return -1;
     }
 
@@ -491,7 +541,8 @@ cp
 
   if(listen(nfd, 3))
     {
-      syslog(LOG_ERR, _("listen: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "listen");
       return -1;
     }
 cp
@@ -516,14 +567,16 @@ cp
 
   if(setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)))
     {
-      syslog(LOG_ERR, _("setsockopt: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "setsockopt");
       return -1;
     }
 
   flags = fcntl(nfd, F_GETFL);
   if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0)
     {
-      syslog(LOG_ERR, _("fcntl: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "fcntl");
       return -1;
     }
 
@@ -604,7 +657,7 @@ int setup_outgoing_connection(char *name)
 {
   conn_list_t *ncn;
   struct hostent *h;
-  config_t *cfg;
+  config_t const *cfg;
 cp
   if(check_id(name))
     {
@@ -651,7 +704,6 @@ cp
   ncn->buffer = xmalloc(MAXBUFSIZE);
   ncn->buflen = 0;
   ncn->last_ping_time = time(NULL);
-  ncn->want_ping = 0;
 
   conn_list_add(ncn);
 
@@ -770,10 +822,12 @@ cp
 
   /* Generate packet encryption key */
 
-  myself->cipher_pkttype = EVP_bf_cbc();
+  myself->cipher_pkttype = EVP_bf_cfb();
+
+  myself->cipher_pktkeylength = myself->cipher_pkttype->key_len + myself->cipher_pkttype->iv_len;
 
-  myself->cipher_pktkey = (char *)xmalloc(64);
-  RAND_bytes(myself->cipher_pktkey, 64);
+  myself->cipher_pktkey = (char *)xmalloc(myself->cipher_pktkeylength);
+  RAND_bytes(myself->cipher_pktkey, myself->cipher_pktkeylength);
 
   if(!(cfg = get_config_val(config, keyexpire)))
     keylifetime = 3600;
@@ -830,12 +884,17 @@ cp
 int setup_network_connections(void)
 {
   config_t const *cfg;
-  char *scriptname;
 cp
   if((cfg = get_config_val(config, pingtimeout)) == NULL)
-    timeout = 5;
+    timeout = 60;
   else
-    timeout = cfg->data.val;
+    {
+      timeout = cfg->data.val;
+      if(timeout < 1)
+        {
+          timeout = 86400;
+        }
+     }
 
   if(setup_tap_fd() < 0)
     return -1;
@@ -844,22 +903,8 @@ cp
     return -1;
 
   /* Run tinc-up script to further initialize the tap interface */
-
-  asprintf(&scriptname, "%s/tinc-up", confbase);
-
-  if(!fork())
-    {
-
-      execl(scriptname, NULL);
-
-      if(errno != ENOENT)
-        syslog(LOG_WARNING, _("Error while executing %s: %m"), scriptname);
-
-      exit(0);
-    }
-
-  free(scriptname);
-
+  execute_script("tinc-up");
+  
   if(!(cfg = get_config_val(config, connectto)))
     /* No upstream IP given, we're listen only. */
     return 0;
@@ -887,7 +932,6 @@ cp
 void close_network_connections(void)
 {
   conn_list_t *p;
-  char *scriptname;
 cp
   for(p = conn_list; p != NULL; p = p->next)
     {
@@ -904,23 +948,11 @@ cp
         myself = NULL;
       }
 
-  /* Execute tinc-down script right before shutting down the interface */
-
-  asprintf(&scriptname, "%s/tinc-down", confbase);
-
-  if(!fork())
-    {
-      execl(scriptname, NULL);
-
-      if(errno != ENOENT)
-        syslog(LOG_WARNING, _("Error while executing %s: %m"), scriptname);
+  close(tap_fd);
 
-      exit(0);
-    }
-      
-  free(scriptname);
+  /* Execute tinc-down script right after shutting down the interface */
+  execute_script("tinc-down");
 
-  close(tap_fd);
   destroy_conn_list();
 
   syslog(LOG_NOTICE, _("Terminating"));
@@ -985,7 +1017,8 @@ cp
 
   if(getpeername(sfd, &ci, &len) < 0)
     {
-      syslog(LOG_ERR, _("Error: getpeername: %m"));
+      syslog(LOG_ERR, _("System call `%s' failed: %m"),
+	     "getpeername");
       return NULL;
     }
 
@@ -997,7 +1030,6 @@ cp
   p->buffer = xmalloc(MAXBUFSIZE);
   p->buflen = 0;
   p->last_ping_time = time(NULL);
-  p->want_ping = 0;
   
   if(debug_lvl >= DEBUG_CONNECTIONS)
     syslog(LOG_NOTICE, _("Connection from %s port %d"),
@@ -1041,6 +1073,7 @@ int handle_incoming_vpn_data()
   vpn_packet_t pkt;
   int x, l = sizeof(x);
   struct sockaddr from;
+  int lenin;
   socklen_t fromlen = sizeof(from);
 cp
   if(getsockopt(myself->socket, SOL_SOCKET, SO_ERROR, &x, &l) < 0)
@@ -1055,18 +1088,17 @@ cp
       return -1;
     }
 
-  if(recvfrom(myself->socket, (char *) &(pkt.len), MTU, 0, &from, &fromlen) <= 0)
+  if((lenin = recvfrom(myself->socket, (char *) &(pkt.len), MTU, 0, &from, &fromlen)) <= 0)
     {
       syslog(LOG_ERR, _("Receiving packet failed: %m"));
       return -1;
     }
-/*
+
   if(debug_lvl >= DEBUG_TRAFFIC)
     {
-      syslog(LOG_DEBUG, _("Received packet of %d bytes from %d.%d.%d.%d"), pkt.len,
-             from.sa_addr[0], from.sa_addr[1], from.sa_addr[2], from.sa_addr[3]);
+      syslog(LOG_DEBUG, _("Received packet of %d bytes"), lenin);
     } 
-*/
+
 cp
   return xrecv(&pkt);
 }
@@ -1151,7 +1183,7 @@ cp
 	{
           if(p->last_ping_time + timeout < now)
             {
-              if(p->status.pinged && !p->status.got_pong)
+              if(p->status.pinged)
                 {
                   if(debug_lvl >= DEBUG_PROTOCOL)
   	            syslog(LOG_INFO, _("%s (%s) didn't respond to PING"),
@@ -1159,12 +1191,9 @@ cp
 	          p->status.timeout = 1;
 	          terminate_connection(p);
                 }
-              else if(p->want_ping)
+              else
                 {
                   send_ping(p);
-                  p->last_ping_time = now;
-                  p->status.pinged = 1;
-                  p->status.got_pong = 0;
                 }
             }
 	}
@@ -1362,7 +1391,7 @@ cp
               if(debug_lvl >= DEBUG_STATUS)
                 syslog(LOG_INFO, _("Regenerating symmetric key"));
                 
-              RAND_bytes(myself->cipher_pktkey, 64);
+              RAND_bytes(myself->cipher_pktkey, myself->cipher_pktkeylength);
               send_key_changed(myself, NULL);
               keyexpires = time(NULL) + keylifetime;
             }