do not print two messages, one is enough

[oweals/gnunet.git] / src / tun / tun.c

diff --git a/src/tun/tun.c b/src/tun/tun.c
index 1ce6605dc1867c28e612c5641b79837d0433cac1..ed3aef1c112e385e5c9eb5e6b142a862aa5cba66 100644 (file)
--- a/src/tun/tun.c
+++ b/src/tun/tun.c
@@ -49,12 +49,13 @@ GNUNET_TUN_initialize_ipv4_header (struct GNUNET_TUN_IPv4Header *ip,
                                   const struct in_addr *src,
                                   const struct in_addr *dst)
 {
+  GNUNET_assert (20 == sizeof (struct GNUNET_TUN_IPv4Header));
   GNUNET_assert (payload_length <= UINT16_MAX - sizeof (struct GNUNET_TUN_IPv4Header));
-  memset (&ip, 0, sizeof (struct GNUNET_TUN_IPv4Header));
+  memset (ip, 0, sizeof (struct GNUNET_TUN_IPv4Header));
   ip->header_length =  sizeof (struct GNUNET_TUN_IPv4Header) / 4;
   ip->version = 4;
   ip->total_length = htons (sizeof (struct GNUNET_TUN_IPv4Header) + payload_length);
-  ip->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, 
+  ip->identification = (uint16_t) GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
                                                            65536);
   ip->ttl = FRESH_TTL;
   ip->protocol = protocol;
@@ -80,14 +81,15 @@ GNUNET_TUN_initialize_ipv6_header (struct GNUNET_TUN_IPv6Header *ip,
                                   const struct in6_addr *src,
                                   const struct in6_addr *dst)
 {
+  GNUNET_assert (40 == sizeof (struct GNUNET_TUN_IPv6Header));
   GNUNET_assert (payload_length <= UINT16_MAX - sizeof (struct GNUNET_TUN_IPv6Header));
-  memset (&ip, 0, sizeof (struct GNUNET_TUN_IPv6Header));
+  memset (ip, 0, sizeof (struct GNUNET_TUN_IPv6Header));
   ip->version = 6;
   ip->next_header = protocol;
   ip->payload_length = htons ((uint16_t) payload_length);
   ip->hop_limit = FRESH_TTL;
   ip->destination_address = *dst;
-  ip->source_address = *src;  
+  ip->source_address = *src;
 }
 
 
@@ -106,18 +108,21 @@ GNUNET_TUN_calculate_tcp4_checksum (const struct GNUNET_TUN_IPv4Header *ip,
                                    uint16_t payload_length)
 {
   uint32_t sum;
-  uint32_t tmp;
+  uint16_t tmp;
 
+  GNUNET_assert (20 == sizeof (struct GNUNET_TUN_TcpHeader));
   GNUNET_assert (payload_length + sizeof (struct GNUNET_TUN_IPv4Header) + sizeof (struct GNUNET_TUN_TcpHeader) ==
                 ntohs (ip->total_length));
   GNUNET_assert (IPPROTO_TCP == ip->protocol);
 
   tcp->crc = 0;
-  sum = GNUNET_CRYPTO_crc16_step (0, 
+  sum = GNUNET_CRYPTO_crc16_step (0,
                                  &ip->source_address,
                                  sizeof (struct in_addr) * 2);
-  tmp = htonl ((IPPROTO_TCP << 16) | (payload_length + sizeof (struct GNUNET_TUN_TcpHeader)));
-  sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint32_t));
+  tmp = htons (IPPROTO_TCP);
+  sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint16_t));
+  tmp = htons (payload_length + sizeof (struct GNUNET_TUN_TcpHeader));
+  sum = GNUNET_CRYPTO_crc16_step (sum, &tmp, sizeof (uint16_t));
   sum = GNUNET_CRYPTO_crc16_step (sum, tcp, sizeof (struct GNUNET_TUN_TcpHeader));
   sum = GNUNET_CRYPTO_crc16_step (sum, payload, payload_length);
   tcp->crc = GNUNET_CRYPTO_crc16_finish (sum);
@@ -141,6 +146,7 @@ GNUNET_TUN_calculate_tcp6_checksum (const struct GNUNET_TUN_IPv6Header *ip,
   uint32_t sum;
   uint32_t tmp;
 
+  GNUNET_assert (20 == sizeof (struct GNUNET_TUN_TcpHeader));
   GNUNET_assert (payload_length + sizeof (struct GNUNET_TUN_TcpHeader) ==
                 ntohs (ip->payload_length));
   GNUNET_assert (IPPROTO_TCP == ip->next_header);
@@ -174,26 +180,27 @@ GNUNET_TUN_calculate_udp4_checksum (const struct GNUNET_TUN_IPv4Header *ip,
   uint32_t sum;
   uint16_t tmp;
 
+  GNUNET_assert (8 == sizeof (struct GNUNET_TUN_UdpHeader));
   GNUNET_assert (payload_length + sizeof (struct GNUNET_TUN_IPv4Header) + sizeof (struct GNUNET_TUN_UdpHeader) ==
                 ntohs (ip->total_length));
   GNUNET_assert (IPPROTO_UDP == ip->protocol);
 
   udp->crc = 0; /* technically optional, but we calculate it anyway, just to be sure */
-  sum = GNUNET_CRYPTO_crc16_step (0, 
+  sum = GNUNET_CRYPTO_crc16_step (0,
                                  &ip->source_address,
                                  sizeof (struct in_addr) * 2);
   tmp = htons (IPPROTO_UDP);
-  sum = GNUNET_CRYPTO_crc16_step (sum, 
-                                 &tmp, 
+  sum = GNUNET_CRYPTO_crc16_step (sum,
+                                 &tmp,
                                  sizeof (uint16_t));
   tmp = htons (sizeof (struct GNUNET_TUN_UdpHeader) + payload_length);
-  sum = GNUNET_CRYPTO_crc16_step (sum, 
-                                 &tmp, 
+  sum = GNUNET_CRYPTO_crc16_step (sum,
+                                 &tmp,
                                  sizeof (uint16_t));
-  sum = GNUNET_CRYPTO_crc16_step (sum, 
-                                 udp, 
+  sum = GNUNET_CRYPTO_crc16_step (sum,
+                                 udp,
                                  sizeof (struct GNUNET_TUN_UdpHeader));
-  sum = GNUNET_CRYPTO_crc16_step (sum, 
+  sum = GNUNET_CRYPTO_crc16_step (sum,
                                  payload,
                                  payload_length);
   udp->crc = GNUNET_CRYPTO_crc16_finish (sum);
@@ -251,6 +258,7 @@ GNUNET_TUN_calculate_icmp_checksum (struct GNUNET_TUN_IcmpHeader *icmp,
 {
   uint32_t sum;
 
+  GNUNET_assert (8 == sizeof (struct GNUNET_TUN_IcmpHeader));
   icmp->crc = 0;
   sum = GNUNET_CRYPTO_crc16_step (0,
                                  icmp,