static inline FAR struct tcp_conn_s *
tcp_ipv4_active(FAR struct net_driver_s *dev, FAR struct tcp_hdr_s *tcp)
{
FAR struct ipv4_hdr_s *ip = IPv4BUF;
FAR struct tcp_conn_s *conn;
in_addr_t srcipaddr;
#ifdef CONFIG_NETDEV_MULTINIC
in_addr_t destipaddr;
#endif
conn = (FAR struct tcp_conn_s *)g_active_tcp_connections.head;
srcipaddr = net_ip4addr_conv32(ip->srcipaddr);
#ifdef CONFIG_NETDEV_MULTINIC
destipaddr = net_ip4addr_conv32(ip->destipaddr);
#endif
while (conn)
{
/* Find an open connection matching the TCP input. The following
* checks are performed:
*
* - The local port number is checked against the destination port
* number in the received packet.
* - The remote port number is checked if the connection is bound
* to a remote port.
* - If multiple network interfaces are supported, then the local
* IP address is available and we will insist that the
* destination IP matches the bound address. If a socket is
* bound to INADDRY_ANY, then it should receive all packets
* directed to the port.
* - Finally, if the connection is bound to a remote IP address,
* the source IP address of the packet is checked.
*
* If all of the above are true then the newly received TCP packet
* is destined for this TCP connection.
*/
if (conn->tcpstateflags != TCP_CLOSED &&
tcp->destport == conn->lport &&
tcp->srcport == conn->rport &&
#ifdef CONFIG_NETDEV_MULTINIC
(net_ipv4addr_cmp(conn->u.ipv4.laddr, INADDR_ANY) ||
net_ipv4addr_cmp(destipaddr, conn->u.ipv4.laddr)) &&
#endif
net_ipv4addr_cmp(srcipaddr, conn->u.ipv4.raddr))
{
/* Matching connection found.. break out of the loop and return a
* reference to it.
*/
break;
}
/* Look at the next active connection */
conn = (FAR struct tcp_conn_s *)conn->node.flink;
}
return conn;
}
static int net_match_ipv4(FAR struct net_route_ipv4_s *route, FAR void *arg)
{
FAR struct route_match_ipv4_s *match = (FAR struct route_match_ipv4_s *)arg;
/* To match, the masked target address must be the same, and the masks
* must be the same.
*/
net_ipv4_dumproute("Comparing", route);
ninfo("With:\n");
ninfo(" target=%08lx netmask=%08lx\n",
htonl(match->target), htonl(match->netmask));
if (net_ipv4addr_maskcmp(route->target, match->target, match->netmask) &&
net_ipv4addr_cmp(route->netmask, match->netmask))
{
/* They match.. a non-zero value to terminate the traversal. The last
* value of index is the index to the matching entry.
*/
return 1;
}
/* Next time we are here, this will be the routing table index */
match->index++;
return 0;
}
FAR struct igmp_group_s *igmp_grpfind(FAR struct net_driver_s *dev,
FAR const in_addr_t *addr)
{
FAR struct igmp_group_s *group;
net_lock_t flags;
grplldbg("Searching for addr %08x\n", (int)*addr);
/* We must disable interrupts because we don't which context we were
* called from.
*/
flags = net_lock();
for (group = (FAR struct igmp_group_s *)dev->grplist.head;
group;
group = group->next)
{
grplldbg("Compare: %08x vs. %08x\n", group->grpaddr, *addr);
if (net_ipv4addr_cmp(group->grpaddr, *addr))
{
grplldbg("Match!\n");
break;
}
}
net_unlock(flags);
return group;
}
static inline FAR struct tcp_conn_s *tcp_ipv4_listener(in_addr_t ipaddr,
uint16_t portno)
{
FAR struct tcp_conn_s *conn;
int i;
/* Check if this port number is in use by any active UIP TCP connection */
for (i = 0; i < CONFIG_NET_TCP_CONNS; i++)
{
conn = &g_tcp_connections[i];
/* Check if this connection is open and the local port assignment
* matches the requested port number.
*/
if (conn->tcpstateflags != TCP_CLOSED && conn->lport == portno)
{
/* If there are multiple interface devices, then the local IP
* address of the connection must also match. INADDR_ANY is a
* special case: There can only be instance of a port number
* with INADDR_ANY.
*/
if (net_ipv4addr_cmp(conn->u.ipv4.laddr, ipaddr) ||
net_ipv4addr_cmp(conn->u.ipv4.laddr, INADDR_ANY))
{
/* The port number is in use, return the connection */
return conn;
}
}
}
return NULL;
}
FAR struct arp_entry *arp_find(in_addr_t ipaddr)
{
FAR struct arp_entry *tabptr;
int i;
for (i = 0; i < CONFIG_NET_ARPTAB_SIZE; ++i)
{
tabptr = &g_arptable[i];
if (net_ipv4addr_cmp(ipaddr, tabptr->at_ipaddr))
{
return tabptr;
}
}
return NULL;
}
static int tcp_find_ipv4_device(FAR struct tcp_conn_s *conn, in_addr_t addr)
{
#ifdef CONFIG_NETDEV_MULTINIC
/* Do nothing if a device is already bound to the connection */
if (conn->dev != NULL)
{
return OK;
}
/* Return success without using device notification if the locally bound
* address is INADDR_ANY. In this case, there may be multiple devices
* that can provide data so the exceptional events from any particular
* device are not important.
*/
if (net_ipv4addr_cmp(addr, INADDR_ANY))
{
return OK;
}
/* There are multiple network devices. We need to select the device that
* is going to route the TCP packet based on the provided IP address.
*/
conn->dev = netdev_findby_ipv4addr(addr, addr);
/* Return success if we found the device */
return conn->dev != NULL ? OK : -ENETUNREACH;
#else
/* There is only a single network device... the one at the head of the
* g_netdevices list.
*/
return (g_netdevices != NULL) ? OK : -ENETUNREACH;
#endif
}
static int net_match(FAR struct net_route_s *route, FAR void *arg)
{
FAR struct route_match_s *match = ( FAR struct route_match_s *)arg;
/* To match, the masked target address must be the same, and the masks
* must be the same.
*/
if (net_ipv4addr_maskcmp(route->target, match->target, match->netmask) &&
net_ipv4addr_cmp(route->netmask, match->netmask))
{
/* They match.. Remove the entry from the routing table */
if (match->prev)
{
(void)sq_remafter((FAR sq_entry_t *)match->prev,
(FAR sq_queue_t *)&g_routes);
}
else
{
(void)sq_remfirst((FAR sq_queue_t *)&g_routes);
}
/* And free the routing table entry by adding it to the free list */
net_freeroute(route);
/* Return a non-zero value to terminate the traversal */
return 1;
}
/* Next time we are here, this will be the previous entry */
match->prev = route;
return 0;
}
int arp_update(in_addr_t ipaddr, FAR uint8_t *ethaddr)
{
struct arp_entry *tabptr = NULL;
int i;
/* Walk through the ARP mapping table and try to find an entry to
* update. If none is found, the IP -> MAC address mapping is
* inserted in the ARP table.
*/
for (i = 0; i < CONFIG_NET_ARPTAB_SIZE; ++i)
{
tabptr = &g_arptable[i];
/* Only check those entries that are actually in use. */
if (tabptr->at_ipaddr != 0)
{
/* Check if the source IP address of the incoming packet matches
* the IP address in this ARP table entry.
*/
if (net_ipv4addr_cmp(ipaddr, tabptr->at_ipaddr))
{
/* An old entry found, update this and return. */
memcpy(tabptr->at_ethaddr.ether_addr_octet, ethaddr, ETHER_ADDR_LEN);
tabptr->at_time = g_arptime;
return OK;
}
}
}
/* If we get here, no existing ARP table entry was found, so we create one. */
/* First, we try to find an unused entry in the ARP table. */
for (i = 0; i < CONFIG_NET_ARPTAB_SIZE; ++i)
{
tabptr = &g_arptable[i];
if (tabptr->at_ipaddr == 0)
{
break;
}
}
/* If no unused entry is found, we try to find the oldest entry and
* throw it away.
*/
if (i == CONFIG_NET_ARPTAB_SIZE)
{
uint8_t tmpage = 0;
int j = 0;
for (i = 0; i < CONFIG_NET_ARPTAB_SIZE; ++i)
{
tabptr = &g_arptable[i];
if (g_arptime - tabptr->at_time > tmpage)
{
tmpage = g_arptime - tabptr->at_time;
j = i;
}
}
i = j;
tabptr = &g_arptable[i];
}
/* Now, i is the ARP table entry which we will fill with the new
* information.
*/
tabptr->at_ipaddr = ipaddr;
memcpy(tabptr->at_ethaddr.ether_addr_octet, ethaddr, ETHER_ADDR_LEN);
tabptr->at_time = g_arptime;
return OK;
}
int ipv4_input(FAR struct net_driver_s *dev)
{
FAR struct ipv4_hdr_s *pbuf = BUF;
uint16_t iplen;
/* This is where the input processing starts. */
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.recv++;
#endif
/* Start of IP input header processing code. */
/* Check validity of the IP header. */
if (pbuf->vhl != 0x45)
{
/* IP version and header length. */
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.drop++;
g_netstats.ipv4.vhlerr++;
#endif
nlldbg("Invalid IP version or header length: %02x\n", pbuf->vhl);
goto drop;
}
/* Check the size of the packet. If the size reported to us in d_len is
* smaller the size reported in the IP header, we assume that the packet
* has been corrupted in transit. If the size of d_len is larger than the
* size reported in the IP packet header, the packet has been padded and
* we set d_len to the correct value.
*/
iplen = (pbuf->len[0] << 8) + pbuf->len[1];
if (iplen <= dev->d_len)
{
dev->d_len = iplen;
}
else
{
nlldbg("IP packet shorter than length in IP header\n");
goto drop;
}
/* Check the fragment flag. */
if ((pbuf->ipoffset[0] & 0x3f) != 0 || pbuf->ipoffset[1] != 0)
{
#if defined(CONFIG_NET_TCP_REASSEMBLY)
dev->d_len = devif_reassembly();
if (dev->d_len == 0)
{
goto drop;
}
#else /* CONFIG_NET_TCP_REASSEMBLY */
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.drop++;
g_netstats.ipv4.fragerr++;
#endif
nlldbg("IP fragment dropped\n");
goto drop;
#endif /* CONFIG_NET_TCP_REASSEMBLY */
}
/* If IP broadcast support is configured, we check for a broadcast
* UDP packet, which may be destined to us (even if there is no IP
* address yet assigned to the device as is the case when we are
* negotiating over DHCP for an address).
*/
#if defined(CONFIG_NET_BROADCAST) && defined(CONFIG_NET_UDP_STACK)
if (pbuf->proto == IP_PROTO_UDP &&
net_ipv4addr_cmp(net_ip4addr_conv32(pbuf->destipaddr),
g_ipv4_alloneaddr))
{
return udp_ipv4_input(dev);
}
/* In most other cases, the device must be assigned a non-zero IP
* address. Another exception is when CONFIG_NET_PINGADDRCONF is
* enabled...
*/
else
#endif
#ifdef CONFIG_NET_ICMP
if (net_ipv4addr_cmp(dev->d_ipaddr, g_ipv4_allzeroaddr))
{
/* If we are configured to use ping IP address configuration and
* hasn't been assigned an IP address yet, we accept all ICMP
* packets.
*/
#ifdef CONFIG_NET_PINGADDRCONF
if (pbuf->proto == IP_PROTO_ICMP)
{
nlldbg("Possible ping config packet received\n");
icmp_input(dev);
goto drop;
}
else
#endif
{
nlldbg("No IP address assigned\n");
goto drop;
}
}
/* Check if the packet is destined for out IP address */
else
#endif
{
/* Check if the packet is destined for our IP address. */
if (!net_ipv4addr_cmp(net_ip4addr_conv32(pbuf->destipaddr), dev->d_ipaddr))
{
#ifdef CONFIG_NET_IGMP
in_addr_t destip = net_ip4addr_conv32(pbuf->destipaddr);
if (igmp_grpfind(dev, &destip) == NULL)
#endif
{
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.drop++;
#endif
goto drop;
}
}
}
if (ipv4_chksum(dev) != 0xffff)
{
/* Compute and check the IP header checksum. */
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.drop++;
g_netstats.ipv4.chkerr++;
#endif
nlldbg("Bad IP checksum\n");
goto drop;
}
/* Make sure that all packet processing logic knows that there is an IPv4
* packet in the device buffer.
*/
IFF_SET_IPv4(dev->d_flags);
/* Now process the incoming packet according to the protocol. */
switch (pbuf->proto)
{
#ifdef CONFIG_NET_TCP_STACK
case IP_PROTO_TCP: /* TCP input */
tcp_ipv4_input(dev);
break;
#endif
#ifdef CONFIG_NET_UDP_STACK
case IP_PROTO_UDP: /* UDP input */
udp_ipv4_input(dev);
break;
#endif
/* Check for ICMP input */
#ifdef CONFIG_NET_ICMP
case IP_PROTO_ICMP: /* ICMP input */
icmp_input(dev);
break;
#endif
/* Check for IGMP input */
#ifdef CONFIG_NET_IGMP
case IP_PROTO_IGMP: /* IGMP input */
igmp_input(dev);
break;
#endif
default: /* Unrecognized/unsupported protocol */
#ifdef CONFIG_NET_STATISTICS
g_netstats.ipv4.drop++;
g_netstats.ipv4.protoerr++;
#endif
nlldbg("Unrecognized IP protocol\n");
goto drop;
}
/* Return and let the caller do any pending transmission. */
return OK;
/* Drop the packet. NOTE that OK is returned meaning that the
* packet has been processed (although processed unsuccessfully).
*/
drop:
dev->d_len = 0;
return OK;
}
