cleanup

1 files changed, 94 insertions, 77 deletions

diff --git a/src/transport/gnunet-nat-client.c b/src/transport/gnunet-nat-client.c
index d38f3bcdf..c5e000d6a 100644
--- a/src/transport/gnunet-nat-client.c
+++ b/src/transport/gnunet-nat-client.c
@@ -70,7 +70,7 @@
 /**
  * IPv4 header.
  */
-struct ip_packet 
+struct ip_header 
 {
 
   /**
@@ -127,7 +127,7 @@ struct ip_packet
 /**
  * Format of ICMP packet.
  */
-struct icmp_packet 
+struct icmp_ttl_exceeded_header 
 {
   uint8_t type;
 
@@ -135,10 +135,12 @@ struct icmp_packet
 
   uint16_t checksum;
 
-  uint32_t reserved;
+  uint32_t unused;
+
+  /* followed by original payload */
 };
 
-struct icmp_echo_packet
+struct icmp_echo_header
 {
   uint8_t type;
 
@@ -147,20 +149,20 @@ struct icmp_echo_packet
   uint16_t checksum;
 
   uint32_t reserved;
-
-  uint32_t data;
 };
 
 /**
  * Beginning of UDP packet.
  */
-struct udp_packet
+struct udp_header
 {
   uint16_t src_port;
 
   uint16_t dst_port;
 
-  uint32_t length;
+  uint16_t length;
+  
+  uint16_t crc;
 };
 
 /**
@@ -187,8 +189,8 @@ static uint16_t port;
  * @return the CRC 16.
  */
 static uint16_t 
-calc_checksum(const uint16_t *data, 
-              unsigned int bytes)
+calc_checksum (const uint16_t *data, 
+               unsigned int bytes)
 {
   uint32_t sum;
   unsigned int i;
@@ -212,19 +214,18 @@ static void
 send_icmp_udp (const struct in_addr *my_ip,
                const struct in_addr *other)
 {
-  struct ip_packet ip_pkt;
-  struct icmp_packet icmp_pkt;
-  struct udp_packet udp_pkt;
-
+  char packet[sizeof(struct ip_header) * 2 + 
+              sizeof(struct icmp_ttl_exceeded_header) + 
+              sizeof(struct udp_header)];
+  struct ip_header ip_pkt;
+  struct icmp_ttl_exceeded_header icmp_pkt;
+  struct udp_header udp_pkt;
   struct sockaddr_in dst;
-  char packet[sizeof(ip_pkt) * 2 + sizeof(icmp_pkt) * 2 + sizeof(uint32_t)];
-
   size_t off;
   int err;
 
   /* ip header: send to (known) ip address */
   off = 0;
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
   ip_pkt.vers_ihl = 0x45;
   ip_pkt.tos = 0;
   ip_pkt.pkt_len = htons(sizeof (packet));
@@ -235,27 +236,27 @@ send_icmp_udp (const struct in_addr *my_ip,
   ip_pkt.checksum = 0;
   ip_pkt.src_ip = my_ip->s_addr;
   ip_pkt.dst_ip = other->s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
-  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
-  off += sizeof(ip_pkt);
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, 
+                                        sizeof (struct ip_header)));
+  memcpy(&packet[off], 
+         &ip_pkt, 
+         sizeof(struct ip_header));
+  off += sizeof(struct ip_header);
 
-  /* ip header of the presumably 'lost' udp packet */
-  ip_pkt.vers_ihl = 0x45;
-  ip_pkt.tos = 0;
-  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct icmp_echo_packet));
-
-  icmp_pkt.type = 11; /* TTL exceeded */
+  icmp_pkt.type = ICMP_TIME_EXCEEDED;
   icmp_pkt.code = 0;
   icmp_pkt.checksum = 0;
-  icmp_pkt.reserved = 0;
-  memcpy(&packet[off], &icmp_pkt, sizeof(icmp_pkt));
-  off += sizeof(icmp_pkt);
+  icmp_pkt.unused = 0;
+  memcpy(&packet[off],
+         &icmp_pkt, 
+         sizeof(struct icmp_ttl_exceeded_header));
+  off += sizeof(struct icmp_ttl_exceeded_header);
 
-  /* build inner IP header */
-  memset(&ip_pkt, 0, sizeof(ip_pkt));
+  /* ip header of the presumably 'lost' udp packet */
   ip_pkt.vers_ihl = 0x45;
   ip_pkt.tos = 0;
-  ip_pkt.pkt_len = htons(sizeof (ip_pkt) + sizeof(udp_pkt));
+  ip_pkt.pkt_len = htons(sizeof (struct ip_header) +
+                         sizeof(struct udp_header));
   ip_pkt.id = htons(0);
   ip_pkt.flags_frag_offset = 0;
   ip_pkt.ttl = 128;
@@ -263,40 +264,48 @@ send_icmp_udp (const struct in_addr *my_ip,
   ip_pkt.checksum = 0;
   ip_pkt.src_ip = other->s_addr;
   ip_pkt.dst_ip = dummy.s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (ip_pkt)));
-  memcpy(&packet[off], &ip_pkt, sizeof(ip_pkt));
-  off += sizeof(ip_pkt);
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt,
+                                        sizeof (struct ip_header)));
+  memcpy(&packet[off], 
+         &ip_pkt, 
+         sizeof(struct ip_header));
+  off += sizeof(struct ip_header);
 
   /* build UDP header */
   udp_pkt.src_port = htons(NAT_TRAV_PORT);
   udp_pkt.dst_port = htons(NAT_TRAV_PORT);
-
-  memset(&udp_pkt.length, 0, sizeof(uint32_t));
-  udp_pkt.length = htons (port);
-  memcpy(&packet[off], &udp_pkt, sizeof(udp_pkt));
-  off += sizeof(udp_pkt);
+  udp_pkt.length = htons (sizeof (struct udp_header));
+  udp_pkt.crc = htons (port);
+  memcpy(&packet[off], 
+         &udp_pkt,
+         sizeof(struct udp_header));
+  off += sizeof(struct udp_header);
 
   /* set ICMP checksum */
-  icmp_pkt.checksum = htons(calc_checksum((uint16_t*)&packet[sizeof(ip_pkt)],
-                            sizeof (icmp_pkt) + sizeof(ip_pkt) + sizeof(udp_pkt)));
-  memcpy (&packet[sizeof(ip_pkt)], &icmp_pkt, sizeof (icmp_pkt));
-
-
+  icmp_pkt.checksum = htons(calc_checksum((uint16_t*)&packet[sizeof(struct ip_header)],
+                                          sizeof (struct icmp_ttl_exceeded_header) +
+                                          sizeof (struct ip_header) +
+                                          sizeof (struct udp_header)));
+  memcpy (&packet[sizeof(struct ip_header)], 
+          &icmp_pkt, 
+          sizeof (struct icmp_ttl_exceeded_header));  
   memset (&dst, 0, sizeof (dst));
   dst.sin_family = AF_INET;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+  dst.sin_len = sizeof (struct sockaddr_in);
+#endif
   dst.sin_addr = *other;
   err = sendto(rawsock,
                packet,
                off, 0,
                (struct sockaddr*)&dst,
                sizeof(dst));
-
   if (err < 0)
     {
       fprintf(stderr,
               "sendto failed: %s\n", strerror(errno));
     }
-  else if (err != off)
+  else if (off != (size_t) err)
     {
       fprintf(stderr,
               "Error: partial send of ICMP message\n");
@@ -314,12 +323,13 @@ static void
 send_icmp (const struct in_addr *my_ip,
            const struct in_addr *other)
 {
-  struct ip_packet ip_pkt;
-  struct icmp_packet icmp_pkt;
-  struct icmp_echo_packet icmp_echo;
+  struct ip_header ip_pkt;
+  struct icmp_ttl_exceeded_header icmp_pkt;
+  struct icmp_echo_header icmp_echo;
   struct sockaddr_in dst;
-  char packet[sizeof (struct ip_packet)*2 + sizeof (struct icmp_packet) + sizeof(struct icmp_echo_packet)];
-
+  char packet[sizeof (struct ip_header) * 2 +
+              sizeof (struct icmp_ttl_exceeded_header) +
+              sizeof (struct icmp_echo_header)];
   size_t off;
   int err;
 
@@ -327,7 +337,7 @@ send_icmp (const struct in_addr *my_ip,
   off = 0;
   ip_pkt.vers_ihl = 0x45;
   ip_pkt.tos = 0;
-  ip_pkt.pkt_len = sizeof (packet); /* huh? */
+  ip_pkt.pkt_len = sizeof (packet);
   ip_pkt.id = 1; 
   ip_pkt.flags_frag_offset = 0;
   ip_pkt.ttl = IPDEFTTL;
@@ -335,24 +345,27 @@ send_icmp (const struct in_addr *my_ip,
   ip_pkt.checksum = 0; 
   ip_pkt.src_ip = my_ip->s_addr;
   ip_pkt.dst_ip = other->s_addr;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct ip_packet)));
-  memcpy (&packet[off], &ip_pkt, sizeof (struct ip_packet));
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, 
+                                        sizeof (struct ip_header)));
+  memcpy (&packet[off], 
+          &ip_pkt, 
+          sizeof (struct ip_header));
   off = sizeof (ip_pkt);
 
   /* icmp reply: time exceeded */
   icmp_pkt.type = ICMP_TIME_EXCEEDED;
   icmp_pkt.code = 0; 
-  icmp_pkt.reserved = 0;
   icmp_pkt.checksum = 0;
+  icmp_pkt.unused = 0;
   memcpy (&packet[off],
           &icmp_pkt,
-          sizeof (struct icmp_packet));
-  off += sizeof (struct icmp_packet);
+          sizeof (struct icmp_ttl_exceeded_header));
+  off += sizeof (struct icmp_ttl_exceeded_header);
 
   /* ip header of the presumably 'lost' udp packet */
   ip_pkt.vers_ihl = 0x45;
   ip_pkt.tos = 0;
-  ip_pkt.pkt_len = (sizeof (struct ip_packet) + sizeof (struct icmp_echo_packet));
+  ip_pkt.pkt_len = (sizeof (struct ip_header) + sizeof (struct icmp_echo_header));
   ip_pkt.id = 1; 
   ip_pkt.flags_frag_offset = 0;
   ip_pkt.ttl = 1; /* real TTL would be 1 on a time exceeded packet */
@@ -360,28 +373,32 @@ send_icmp (const struct in_addr *my_ip,
   ip_pkt.src_ip = other->s_addr;
   ip_pkt.dst_ip = dummy.s_addr;
   ip_pkt.checksum = 0;
-  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt, sizeof (struct ip_packet)));  
-  memcpy (&packet[off], &ip_pkt, sizeof (struct ip_packet));
-  off += sizeof (struct ip_packet);
+  ip_pkt.checksum = htons(calc_checksum((uint16_t*)&ip_pkt,
+                                        sizeof (struct ip_header)));  
+  memcpy (&packet[off], 
+          &ip_pkt, 
+          sizeof (struct ip_header));
+  off += sizeof (struct ip_header);
 
   icmp_echo.type = ICMP_ECHO;
   icmp_echo.code = 0;
-  icmp_echo.reserved = 0;
+  icmp_echo.reserved = htonl (port);
   icmp_echo.checksum = 0;
-  icmp_echo.data = htons(port);
   icmp_echo.checksum = htons(calc_checksum((uint16_t*) &icmp_echo, 
-                                           sizeof (struct icmp_echo_packet)));
+                                           sizeof (struct icmp_echo_header)));
   memcpy (&packet[off], 
           &icmp_echo,
-          sizeof(struct icmp_echo_packet));
+          sizeof(struct icmp_echo_header));
 
   /* no go back to calculate ICMP packet checksum */
-  off = sizeof (ip_pkt);
+  off = sizeof (struct ip_header);
   icmp_pkt.checksum = htons(calc_checksum((uint16_t*) &packet[off],
-                                          sizeof (struct icmp_packet) + sizeof(struct ip_packet) + sizeof(struct icmp_echo_packet)));
+                                          sizeof (struct icmp_ttl_exceeded_header) + 
+                                          sizeof(struct ip_header) + 
+                                          sizeof(struct icmp_echo_header)));
   memcpy (&packet[off],
           &icmp_pkt,
-          sizeof (struct icmp_packet));
+          sizeof (struct icmp_ttl_exceeded_header));
 
   /* prepare for transmission */
   memset (&dst, 0, sizeof (dst));
@@ -400,7 +417,7 @@ send_icmp (const struct in_addr *my_ip,
       fprintf(stderr,
               "sendto failed: %s\n", strerror(errno));
     }
-  else if (err != sizeof (packet)) 
+  else if (sizeof (packet) != (size_t) err) 
     {
       fprintf(stderr,
               "Error: partial send of ICMP message\n");
@@ -427,8 +444,8 @@ make_raw_socket ()
                strerror (errno));
       return -1;
     }  
-  if (setsockopt(ret, SOL_SOCKET, SO_BROADCAST,
-                 (char *)&one, sizeof(one)) == -1)
+  if (-1 == setsockopt(ret, SOL_SOCKET, SO_BROADCAST,
+                       (char *)&one, sizeof(one)))
     {
       fprintf(stderr,
               "setsockopt failed: %s\n",
@@ -436,8 +453,8 @@ make_raw_socket ()
       close (ret);
       return -1;
     }
-  if (setsockopt(ret, IPPROTO_IP, IP_HDRINCL,
-                 (char *)&one, sizeof(one)) == -1)
+  if (-1 == setsockopt(ret, IPPROTO_IP, IP_HDRINCL,
+                       (char *)&one, sizeof(one)))
     {
       fprintf(stderr,
               "setsockopt failed: %s\n",
@@ -457,7 +474,7 @@ main (int argc, char *const *argv)
   uid_t uid;
   unsigned int p;
 
-  if (argc != 4)
+  if (4 != argc)
     {
       fprintf (stderr,
                "This program must be started with our IP, the targets external IP, and our port as arguments.\n");
@@ -472,8 +489,8 @@ main (int argc, char *const *argv)
       return 1;
     }
   if ( (1 != sscanf (argv[3], "%u", &p) ) ||
-       (p == 0) ||
-       (p > 0xFFFF) )
+       (0 == p) ||
+       (0xFFFF < p) )
     {
       fprintf (stderr,
                "Error parsing port value `%s'\n",