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diff --git a/src/VBox/Devices/Network/lwip-new/src/core/ipv4/ip4.c b/src/VBox/Devices/Network/lwip-new/src/core/ipv4/ip4.c
new file mode 100644
index 00000000..19942b0b
--- /dev/null
+++ b/src/VBox/Devices/Network/lwip-new/src/core/ipv4/ip4.c
@@ -0,0 +1,1027 @@
+/**
+ * @file
+ * This is the IPv4 layer implementation for incoming and outgoing IP traffic.
+ *
+ * @see ip_frag.c
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip_frag.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/icmp.h"
+#include "lwip/igmp.h"
+#include "lwip/raw.h"
+#include "lwip/udp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/snmp.h"
+#include "lwip/dhcp.h"
+#include "lwip/autoip.h"
+#include "lwip/stats.h"
+#include "arch/perf.h"
+
+#include <string.h>
+
+/* see comment in "lwip/ip.h" */
+#ifdef IP_HDRINCL
+#undef IP_HDRINCL
+#endif
+#define IP_HDRINCL LWIP_IP_HDRINCL
+
+/** Set this to 0 in the rare case of wanting to call an extra function to
+ * generate the IP checksum (in contrast to calculating it on-the-fly). */
+#ifndef LWIP_INLINE_IP_CHKSUM
+#define LWIP_INLINE_IP_CHKSUM 1
+#endif
+#if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP
+#define CHECKSUM_GEN_IP_INLINE 1
+#else
+#define CHECKSUM_GEN_IP_INLINE 0
+#endif
+
+#if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT)
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 1
+
+/** Some defines for DHCP to let link-layer-addressed packets through while the
+ * netif is down.
+ * To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT
+ * to return 1 if the port is accepted and 0 if the port is not accepted.
+ */
+#if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT)
+/* accept DHCP client port and custom port */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \
+ || (LWIP_IP_ACCEPT_UDP_PORT(port)))
+#elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept custom port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(port))
+#else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+/* accept DHCP client port only */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT))
+#endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
+
+#else /* LWIP_DHCP */
+#define IP_ACCEPT_LINK_LAYER_ADDRESSING 0
+#endif /* LWIP_DHCP */
+
+/** Global data for both IPv4 and IPv6 */
+struct ip_globals ip_data;
+
+/** The IP header ID of the next outgoing IP packet */
+static u16_t ip_id;
+
+#if LWIP_CONNECTION_PROXY
+proxy_ip4_divert_hook_fn proxy_ip4_divert_hook;
+#endif
+
+
+/**
+ * Finds the appropriate network interface for a given IP address. It
+ * searches the list of network interfaces linearly. A match is found
+ * if the masked IP address of the network interface equals the masked
+ * IP address given to the function.
+ *
+ * @param dest the destination IP address for which to find the route
+ * @return the netif on which to send to reach dest
+ */
+struct netif *
+ip_route(ip_addr_t *dest)
+{
+ struct netif *netif;
+
+#ifdef LWIP_HOOK_IP4_ROUTE
+ netif = LWIP_HOOK_IP4_ROUTE(dest);
+ if (netif != NULL) {
+ return netif;
+ }
+#endif
+
+ /* iterate through netifs */
+ for (netif = netif_list; netif != NULL; netif = netif->next) {
+ /* network mask matches? */
+ if (netif_is_up(netif)) {
+ if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
+ /* return netif on which to forward IP packet */
+ return netif;
+ }
+ }
+ }
+ if ((netif_default == NULL) || (!netif_is_up(netif_default))) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+ IP_STATS_INC(ip.rterr);
+ snmp_inc_ipoutnoroutes();
+ return NULL;
+ }
+ /* no matching netif found, use default netif */
+ return netif_default;
+}
+
+#if IP_FORWARD
+/**
+ * Determine whether an IP address is in a reserved set of addresses
+ * that may not be forwarded, or whether datagrams to that destination
+ * may be forwarded.
+ * @param p the packet to forward
+ * @param dest the destination IP address
+ * @return 1: can forward 0: discard
+ */
+static int
+ip_canforward(struct pbuf *p)
+{
+ u32_t addr = ntohl(ip4_addr_get_u32(ip_current_dest_addr()));
+
+ if (p->flags & PBUF_FLAG_LLBCAST) {
+ /* don't route link-layer broadcasts */
+ return 0;
+ }
+ if ((p->flags & PBUF_FLAG_LLMCAST) && !IP_MULTICAST(addr)) {
+ /* don't route link-layer multicasts unless the destination address is an IP
+ multicast address */
+ return 0;
+ }
+ if (IP_EXPERIMENTAL(addr)) {
+ return 0;
+ }
+ if (IP_CLASSA(addr)) {
+ u32_t net = addr & IP_CLASSA_NET;
+ if ((net == 0) || (net == ((u32_t)IP_LOOPBACKNET << IP_CLASSA_NSHIFT))) {
+ /* don't route loopback packets */
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/**
+ * Forwards an IP packet. It finds an appropriate route for the
+ * packet, decrements the TTL value of the packet, adjusts the
+ * checksum and outputs the packet on the appropriate interface.
+ *
+ * @param p the packet to forward (p->payload points to IP header)
+ * @param iphdr the IP header of the input packet
+ * @param inp the netif on which this packet was received
+ * @return -1 if packet is to be dropped, 0 if there's no route, 1 if forwarded
+ */
+static int
+ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
+{
+ struct netif *netif;
+ int forwarded = -1;
+
+ PERF_START;
+
+ if (!ip_canforward(p)) {
+ goto return_noroute;
+ }
+
+ /* RFC3927 2.7: do not forward link-local addresses */
+ if (ip_addr_islinklocal(ip_current_dest_addr())) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(ip_current_dest_addr()), ip4_addr2_16(ip_current_dest_addr()),
+ ip4_addr3_16(ip_current_dest_addr()), ip4_addr4_16(ip_current_dest_addr())));
+ goto return_noroute;
+ }
+
+ /* Find network interface where to forward this IP packet to. */
+ netif = ip_route(ip_current_dest_addr());
+ if (netif == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
+ ip4_addr1_16(ip_current_dest_addr()), ip4_addr2_16(ip_current_dest_addr()),
+ ip4_addr3_16(ip_current_dest_addr()), ip4_addr4_16(ip_current_dest_addr())));
+ /* @todo: send ICMP_DUR_NET? */
+ forwarded = 0; /* but try connection proxy if configured */
+ goto return_noroute;
+ }
+
+#if LWIP_CONNECTION_PROXY
+ /* The packet is for a destination on a directly connected network.
+ * Check for addresses in that address space that proxy wants to
+ * remap (e.g. to host loopback address/es) and hand it off to
+ * proxy */
+ if (netif != netif_default
+ && proxy_ip4_divert_hook != NULL
+ && (*proxy_ip4_divert_hook)(netif, ip_current_dest_addr()))
+ {
+ forwarded = 0;
+ goto return_noroute;
+ }
+#endif /* LWIP_CONNECTION_PROXY */
+
+#if !IP_FORWARD_ALLOW_TX_ON_RX_NETIF
+ /* Do not forward packets onto the same network interface on which
+ * they arrived. */
+ if (netif == inp) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
+ goto return_noroute;
+ }
+#endif /* IP_FORWARD_ALLOW_TX_ON_RX_NETIF */
+
+ /* decrement TTL */
+ IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
+ /* send ICMP if TTL == 0 */
+ if (IPH_TTL(iphdr) == 0) {
+ snmp_inc_ipinhdrerrors();
+#if LWIP_ICMP
+ /* Don't send ICMP messages in response to ICMP messages */
+ if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
+ icmp_time_exceeded(p, ICMP_TE_TTL);
+ }
+#endif /* LWIP_ICMP */
+ return -1;
+ }
+
+ /* Incrementally update the IP checksum. */
+ if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffffU - 0x100)) {
+ IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1);
+ } else {
+ IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100));
+ }
+
+ LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(ip_current_dest_addr()), ip4_addr2_16(ip_current_dest_addr()),
+ ip4_addr3_16(ip_current_dest_addr()), ip4_addr4_16(ip_current_dest_addr())));
+
+ IP_STATS_INC(ip.fw);
+ IP_STATS_INC(ip.xmit);
+ snmp_inc_ipforwdatagrams();
+
+ PERF_STOP("ip_forward");
+ /* don't fragment if interface has mtu set to 0 [loopif] */
+ if (netif->mtu && (p->tot_len > netif->mtu)) {
+ if ((IPH_OFFSET(iphdr) & PP_NTOHS(IP_DF)) == 0) {
+#if IP_FRAG
+ ip_frag(p, netif, ip_current_dest_addr());
+ forwarded = 1;
+#else /* IP_FRAG */
+ /* @todo: send ICMP Destination Unreacheable code 13 "Communication administratively prohibited"? */
+ forwarded = -1;
+#endif /* IP_FRAG */
+ } else {
+ /* send ICMP Destination Unreacheable code 4: "Fragmentation Needed and DF Set" */
+ icmp_dest_unreach(p, ICMP_DUR_FRAG);
+ forwarded = -1;
+ }
+ return forwarded;
+ }
+ /* transmit pbuf on chosen interface */
+ netif->output(netif, p, ip_current_dest_addr());
+ return 1;
+
+return_noroute:
+#if LWIP_CONNECTION_PROXY
+ if (forwarded < 0)
+#endif
+ {
+ snmp_inc_ipoutnoroutes();
+ }
+ return forwarded;
+}
+#endif /* IP_FORWARD */
+
+/**
+ * This function is called by the network interface device driver when
+ * an IP packet is received. The function does the basic checks of the
+ * IP header such as packet size being at least larger than the header
+ * size etc. If the packet was not destined for us, the packet is
+ * forwarded (using ip_forward). The IP checksum is always checked.
+ *
+ * Finally, the packet is sent to the upper layer protocol input function.
+ *
+ * @param p the received IP packet (p->payload points to IP header)
+ * @param inp the netif on which this packet was received
+ * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
+ * processed, but currently always returns ERR_OK)
+ */
+err_t
+ip_input(struct pbuf *p, struct netif *inp)
+{
+ struct ip_hdr *iphdr;
+ struct netif *netif;
+ u16_t iphdr_hlen;
+ u16_t iphdr_len;
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+ int check_ip_src=1;
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+#if LWIP_CONNECTION_PROXY
+ int proxy = 0;
+#endif
+
+ IP_STATS_INC(ip.recv);
+ snmp_inc_ipinreceives();
+
+ /* identify the IP header */
+ iphdr = (struct ip_hdr *)p->payload;
+ if (IPH_V(iphdr) != 4) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr)));
+ ip_debug_print(p);
+ pbuf_free(p);
+ IP_STATS_INC(ip.err);
+ IP_STATS_INC(ip.drop);
+ snmp_inc_ipinhdrerrors();
+ return ERR_OK;
+ }
+
+#ifdef LWIP_HOOK_IP4_INPUT
+ if (LWIP_HOOK_IP4_INPUT(p, inp)) {
+ /* the packet has been eaten */
+ return ERR_OK;
+ }
+#endif
+
+ /* obtain IP header length in number of 32-bit words */
+ iphdr_hlen = IPH_HL(iphdr);
+ /* calculate IP header length in bytes */
+ iphdr_hlen *= 4;
+ /* obtain ip length in bytes */
+ iphdr_len = ntohs(IPH_LEN(iphdr));
+
+ /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
+ if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) {
+ if (iphdr_hlen > p->len) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+ ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
+ iphdr_hlen, p->len));
+ }
+ if (iphdr_len > p->tot_len) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+ ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
+ iphdr_len, p->tot_len));
+ }
+ /* free (drop) packet pbufs */
+ pbuf_free(p);
+ IP_STATS_INC(ip.lenerr);
+ IP_STATS_INC(ip.drop);
+ snmp_inc_ipindiscards();
+ return ERR_OK;
+ }
+
+ /* verify checksum */
+#if CHECKSUM_CHECK_IP
+ if (inet_chksum(iphdr, iphdr_hlen) != 0) {
+
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+ ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen)));
+ ip_debug_print(p);
+ pbuf_free(p);
+ IP_STATS_INC(ip.chkerr);
+ IP_STATS_INC(ip.drop);
+ snmp_inc_ipinhdrerrors();
+ return ERR_OK;
+ }
+#endif
+
+ /* Trim pbuf. This should have been done at the netif layer,
+ * but we'll do it anyway just to be sure that its done. */
+ pbuf_realloc(p, iphdr_len);
+
+ /* copy IP addresses to aligned ip_addr_t */
+ ip_addr_copy(*ipX_2_ip(&ip_data.current_iphdr_dest), iphdr->dest);
+ ip_addr_copy(*ipX_2_ip(&ip_data.current_iphdr_src), iphdr->src);
+
+ /* match packet against an interface, i.e. is this packet for us? */
+#if LWIP_IGMP
+ if (ip_addr_ismulticast(ip_current_dest_addr())) {
+ if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, ip_current_dest_addr()))) {
+ netif = inp;
+ } else {
+ netif = NULL;
+ }
+ } else
+#endif /* LWIP_IGMP */
+ {
+ /* start trying with inp. if that's not acceptable, start walking the
+ list of configured netifs.
+ 'first' is used as a boolean to mark whether we started walking the list */
+ int first = 1;
+ netif = inp;
+ do {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input:"
+ " iphdr->dest %"U16_F".%"U16_F".%"U16_F".%"U16_F
+ " netif->ip_addr %"U16_F".%"U16_F".%"U16_F".%"U16_F
+ "/%"U16_F".%"U16_F".%"U16_F".%"U16_F
+ " (0x%08"X32_F", 0x%08"X32_F", 0x%08"X32_F")\n",
+ ip4_addr1_16(&iphdr->dest), ip4_addr2_16(&iphdr->dest),
+ ip4_addr3_16(&iphdr->dest), ip4_addr4_16(&iphdr->dest),
+ ip4_addr1_16(&netif->ip_addr), ip4_addr2_16(&netif->ip_addr),
+ ip4_addr3_16(&netif->ip_addr), ip4_addr4_16(&netif->ip_addr),
+ ip4_addr1_16(&netif->netmask), ip4_addr2_16(&netif->netmask),
+ ip4_addr3_16(&netif->netmask), ip4_addr4_16(&netif->netmask),
+ ntohl(ip4_addr_get_u32(&iphdr->dest)
+ & ip4_addr_get_u32(&netif->netmask)),
+ ntohl(ip4_addr_get_u32(&netif->ip_addr)
+ & ip4_addr_get_u32(&netif->netmask)),
+ ntohl(ip4_addr_get_u32(&iphdr->dest)
+ & ~ip4_addr_get_u32(&netif->netmask))));
+
+ /* interface is up and configured? */
+ if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) {
+ /* unicast to this interface address? */
+ if (ip_addr_cmp(ip_current_dest_addr(), &(netif->ip_addr)) ||
+ /* or broadcast on this interface network address? */
+ ip_addr_isbroadcast(ip_current_dest_addr(), netif)) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n",
+ netif->name[0], netif->name[1]));
+ /* break out of for loop */
+ break;
+ }
+#if LWIP_AUTOIP
+ /* connections to link-local addresses must persist after changing
+ the netif's address (RFC3927 ch. 1.9) */
+ if ((netif->autoip != NULL) &&
+ ip_addr_cmp(ip_current_dest_addr(), &(netif->autoip->llipaddr))) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n",
+ netif->name[0], netif->name[1]));
+ /* break out of for loop */
+ break;
+ }
+#endif /* LWIP_AUTOIP */
+ }
+ if (first) {
+ first = 0;
+ netif = netif_list;
+ } else {
+ netif = netif->next;
+ }
+ if (netif == inp) {
+ netif = netif->next;
+ }
+ } while(netif != NULL);
+ }
+
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+ /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
+ * using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
+ * According to RFC 1542 section 3.1.1, referred by RFC 2131).
+ *
+ * If you want to accept private broadcast communication while a netif is down,
+ * define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.:
+ *
+ * #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345))
+ */
+ if (netif == NULL) {
+ /* remote port is DHCP server? */
+ if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
+ struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen);
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
+ ntohs(udphdr->dest)));
+ if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n"));
+ netif = inp;
+ check_ip_src = 0;
+ }
+ }
+ }
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+
+ /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */
+#if IP_ACCEPT_LINK_LAYER_ADDRESSING
+ /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */
+ if (check_ip_src && !ip_addr_isany(ip_current_src_addr()))
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+ { if ((ip_addr_isbroadcast(ip_current_src_addr(), inp)) ||
+ (ip_addr_ismulticast(ip_current_src_addr()))) {
+ /* packet source is not valid */
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n"));
+ /* free (drop) packet pbufs */
+ pbuf_free(p);
+ IP_STATS_INC(ip.drop);
+ snmp_inc_ipinaddrerrors();
+ snmp_inc_ipindiscards();
+ return ERR_OK;
+ }
+ }
+
+ /* packet not for us? */
+ if (netif == NULL) {
+ /* packet not for us, route or discard */
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
+#if IP_FORWARD
+ /* non-broadcast packet? */
+ if (!ip_addr_isbroadcast(ip_current_dest_addr(), inp)) {
+ /* try to forward IP packet on (other) interfaces */
+#if LWIP_CONNECTION_PROXY
+ int forwarded =
+#endif
+ ip_forward(p, iphdr, inp);
+#if LWIP_CONNECTION_PROXY
+ if (forwarded == 0) {
+ proxy = 1;
+ netif = inp;
+ }
+#endif
+ } else
+#endif /* IP_FORWARD */
+ {
+ snmp_inc_ipinaddrerrors();
+ snmp_inc_ipindiscards();
+ }
+
+#if LWIP_CONNECTION_PROXY
+ if (!proxy)
+#endif
+ {
+ pbuf_free(p);
+ return ERR_OK;
+ }
+ }
+
+ /* packet consists of multiple fragments? */
+ if ((IPH_OFFSET(iphdr) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) {
+#if IP_REASSEMBLY /* packet fragment reassembly code present? */
+ LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n",
+ ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8));
+ /* reassemble the packet*/
+ p = ip_reass(p);
+ /* packet not fully reassembled yet? */
+ if (p == NULL) {
+ return ERR_OK;
+ }
+ iphdr = (struct ip_hdr *)p->payload;
+#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
+ pbuf_free(p);
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
+ ntohs(IPH_OFFSET(iphdr))));
+ IP_STATS_INC(ip.opterr);
+ IP_STATS_INC(ip.drop);
+ /* unsupported protocol feature */
+ snmp_inc_ipinunknownprotos();
+ return ERR_OK;
+#endif /* IP_REASSEMBLY */
+ }
+
+#if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */
+
+#if LWIP_IGMP
+ /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */
+ if((iphdr_hlen > IP_HLEN) && (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) {
+#else
+ if (iphdr_hlen > IP_HLEN) {
+#endif /* LWIP_IGMP */
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n"));
+ pbuf_free(p);
+ IP_STATS_INC(ip.opterr);
+ IP_STATS_INC(ip.drop);
+ /* unsupported protocol feature */
+ snmp_inc_ipinunknownprotos();
+ return ERR_OK;
+ }
+#endif /* IP_OPTIONS_ALLOWED == 0 */
+
+ /* send to upper layers */
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n"));
+ ip_debug_print(p);
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
+
+ ip_data.current_netif = inp;
+ ip_data.current_ip4_header = iphdr;
+ ip_data.current_ip_header_tot_len = IPH_HL(iphdr) * 4;
+
+#if LWIP_CONNECTION_PROXY
+ if (proxy) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_input: proxying\n"));
+
+ pbuf_header(p, -iphdr_hlen); /* Move to payload, no check necessary. */
+
+ switch (IPH_PROTO(iphdr)) {
+
+#if LWIP_ICMP
+ case IP_PROTO_ICMP:
+ icmp_proxy_input(p, inp);
+ break;
+#endif
+
+#if LWIP_UDP
+ case IP_PROTO_UDP:
+#if LWIP_UDPLITE
+ case IP_PROTO_UDPLITE:
+#endif /* LWIP_UDPLITE */
+ udp_proxy_input(p, inp);
+ break;
+#endif /* LWIP_UDP */
+
+#if LWIP_TCP
+ case IP_PROTO_TCP:
+ tcp_proxy_input(p, inp);
+ break;
+#endif /* LWIP_TCP */
+
+ default:
+ /* no proxy support for this protocol */
+ /* XXX: TODO: icmp administratively prohibited? */
+ pbuf_free(p);
+ break;
+ }
+ } else
+#endif /* LWIP_CONNECTION_PROXY */
+#if LWIP_RAW
+ /* raw input did not eat the packet? */
+ if (raw_input(p, inp) == 0)
+#endif /* LWIP_RAW */
+ {
+ pbuf_header(p, -iphdr_hlen); /* Move to payload, no check necessary. */
+
+ switch (IPH_PROTO(iphdr)) {
+#if LWIP_UDP
+ case IP_PROTO_UDP:
+#if LWIP_UDPLITE
+ case IP_PROTO_UDPLITE:
+#endif /* LWIP_UDPLITE */
+ snmp_inc_ipindelivers();
+ udp_input(p, inp);
+ break;
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+ case IP_PROTO_TCP:
+ snmp_inc_ipindelivers();
+ tcp_input(p, inp);
+ break;
+#endif /* LWIP_TCP */
+#if LWIP_ICMP
+ case IP_PROTO_ICMP:
+ snmp_inc_ipindelivers();
+ icmp_input(p, inp);
+ break;
+#endif /* LWIP_ICMP */
+#if LWIP_IGMP
+ case IP_PROTO_IGMP:
+ igmp_input(p, inp, ip_current_dest_addr());
+ break;
+#endif /* LWIP_IGMP */
+ default:
+#if LWIP_ICMP
+ /* send ICMP destination protocol unreachable unless is was a broadcast */
+ if (!ip_addr_isbroadcast(ip_current_dest_addr(), inp) &&
+ !ip_addr_ismulticast(ip_current_dest_addr())) {
+ pbuf_header(p, iphdr_hlen); /* Move to ip header, no check necessary. */
+ p->payload = iphdr;
+ icmp_dest_unreach(p, ICMP_DUR_PROTO);
+ }
+#endif /* LWIP_ICMP */
+ pbuf_free(p);
+
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
+
+ IP_STATS_INC(ip.proterr);
+ IP_STATS_INC(ip.drop);
+ snmp_inc_ipinunknownprotos();
+ }
+ }
+
+ /* @todo: this is not really necessary... */
+ ip_data.current_netif = NULL;
+ ip_data.current_ip4_header = NULL;
+ ip_data.current_ip_header_tot_len = 0;
+ ip_addr_set_any(ip_current_src_addr());
+ ip_addr_set_any(ip_current_dest_addr());
+
+ return ERR_OK;
+}
+
+/**
+ * Sends an IP packet on a network interface. This function constructs
+ * the IP header and calculates the IP header checksum. If the source
+ * IP address is NULL, the IP address of the outgoing network
+ * interface is filled in as source address.
+ * If the destination IP address is IP_HDRINCL, p is assumed to already
+ * include an IP header and p->payload points to it instead of the data.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+ protocol header; if dest == IP_HDRINCL, p already includes an IP
+ header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ * IP address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param netif the netif on which to send this packet
+ * @return ERR_OK if the packet was sent OK
+ * ERR_BUF if p doesn't have enough space for IP/LINK headers
+ * returns errors returned by netif->output
+ *
+ * @note ip_id: RFC791 "some host may be able to simply use
+ * unique identifiers independent of destination"
+ */
+err_t
+ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+ u8_t ttl, u8_t tos,
+ u8_t proto, struct netif *netif)
+{
+#if IP_OPTIONS_SEND
+ return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0);
+}
+
+/**
+ * Same as ip_output_if() but with the possibility to include IP options:
+ *
+ * @ param ip_options pointer to the IP options, copied into the IP header
+ * @ param optlen length of ip_options
+ */
+err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+ u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
+ u16_t optlen)
+{
+#endif /* IP_OPTIONS_SEND */
+ struct ip_hdr *iphdr;
+ ip_addr_t dest_addr;
+#if CHECKSUM_GEN_IP_INLINE
+ u32_t chk_sum = 0;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+ /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+ gets altered as the packet is passed down the stack */
+ LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+ snmp_inc_ipoutrequests();
+
+ /* Should the IP header be generated or is it already included in p? */
+ if (dest != IP_HDRINCL) {
+ u16_t ip_hlen = IP_HLEN;
+#if IP_OPTIONS_SEND
+ u16_t optlen_aligned = 0;
+ if (optlen != 0) {
+#if CHECKSUM_GEN_IP_INLINE
+ int i;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ /* round up to a multiple of 4 */
+ optlen_aligned = ((optlen + 3) & ~3);
+ ip_hlen += optlen_aligned;
+ /* First write in the IP options */
+ if (pbuf_header(p, optlen_aligned)) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n"));
+ IP_STATS_INC(ip.err);
+ snmp_inc_ipoutdiscards();
+ return ERR_BUF;
+ }
+ MEMCPY(p->payload, ip_options, optlen);
+ if (optlen < optlen_aligned) {
+ /* zero the remaining bytes */
+ memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen);
+ }
+#if CHECKSUM_GEN_IP_INLINE
+ for (i = 0; i < optlen_aligned/2; i++) {
+ chk_sum += ((u16_t*)p->payload)[i];
+ }
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ }
+#endif /* IP_OPTIONS_SEND */
+ /* generate IP header */
+ if (pbuf_header(p, IP_HLEN)) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n"));
+
+ IP_STATS_INC(ip.err);
+ snmp_inc_ipoutdiscards();
+ return ERR_BUF;
+ }
+
+ iphdr = (struct ip_hdr *)p->payload;
+ LWIP_ASSERT("check that first pbuf can hold struct ip_hdr",
+ (p->len >= sizeof(struct ip_hdr)));
+
+ IPH_TTL_SET(iphdr, ttl);
+ IPH_PROTO_SET(iphdr, proto);
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += LWIP_MAKE_U16(proto, ttl);
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+ /* dest cannot be NULL here */
+ ip_addr_copy(iphdr->dest, *dest);
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF;
+ chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+ IPH_VHL_SET(iphdr, 4, ip_hlen / 4);
+ IPH_TOS_SET(iphdr, tos);
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += LWIP_MAKE_U16(tos, iphdr->_v_hl);
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ IPH_LEN_SET(iphdr, htons(p->tot_len));
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += iphdr->_len;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ IPH_OFFSET_SET(iphdr, 0);
+ IPH_ID_SET(iphdr, htons(ip_id));
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += iphdr->_id;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ ++ip_id;
+
+ if (ip_addr_isany(src)) {
+ ip_addr_copy(iphdr->src, netif->ip_addr);
+ } else {
+ /* src cannot be NULL here */
+ ip_addr_copy(iphdr->src, *src);
+ }
+
+#if CHECKSUM_GEN_IP_INLINE
+ chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF;
+ chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16;
+ chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF);
+ chk_sum = (chk_sum >> 16) + chk_sum;
+ chk_sum = ~chk_sum;
+ iphdr->_chksum = chk_sum; /* network order */
+#else /* CHECKSUM_GEN_IP_INLINE */
+ IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+ IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
+#endif
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ } else {
+ /* IP header already included in p */
+ iphdr = (struct ip_hdr *)p->payload;
+ ip_addr_copy(dest_addr, iphdr->dest);
+ dest = &dest_addr;
+ }
+
+ IP_STATS_INC(ip.xmit);
+
+ LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
+ ip_debug_print(p);
+
+#if ENABLE_LOOPBACK
+ if (ip_addr_cmp(dest, &netif->ip_addr)) {
+ /* Packet to self, enqueue it for loopback */
+ LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()\n"));
+ return netif_loop_output(netif, p);
+ }
+#if LWIP_IGMP
+ if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
+ netif_loop_output(netif, p);
+ }
+#endif /* LWIP_IGMP */
+#endif /* ENABLE_LOOPBACK */
+#if IP_FRAG
+ /* don't fragment if interface has mtu set to 0 [loopif] */
+ if (netif->mtu && (p->tot_len > netif->mtu)) {
+ return ip_frag(p, netif, dest);
+ }
+#endif /* IP_FRAG */
+
+ LWIP_DEBUGF(IP_DEBUG, ("netif->output()\n"));
+ return netif->output(netif, p, dest);
+}
+
+/**
+ * Simple interface to ip_output_if. It finds the outgoing network
+ * interface and calls upon ip_output_if to do the actual work.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+ protocol header; if dest == IP_HDRINCL, p already includes an IP
+ header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ * IP address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ *
+ * @return ERR_RTE if no route is found
+ * see ip_output_if() for more return values
+ */
+err_t
+ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+ u8_t ttl, u8_t tos, u8_t proto)
+{
+ struct netif *netif;
+
+ /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+ gets altered as the packet is passed down the stack */
+ LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+ if ((netif = ip_route(dest)) == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+ IP_STATS_INC(ip.rterr);
+ return ERR_RTE;
+ }
+
+ return ip_output_if(p, src, dest, ttl, tos, proto, netif);
+}
+
+#if LWIP_NETIF_HWADDRHINT
+/** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
+ * before calling ip_output_if.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+ protocol header; if dest == IP_HDRINCL, p already includes an IP
+ header and p->payload points to that IP header)
+ * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
+ * IP address of the netif used to send is used as source address)
+ * @param dest the destination IP address to send the packet to
+ * @param ttl the TTL value to be set in the IP header
+ * @param tos the TOS value to be set in the IP header
+ * @param proto the PROTOCOL to be set in the IP header
+ * @param addr_hint address hint pointer set to netif->addr_hint before
+ * calling ip_output_if()
+ *
+ * @return ERR_RTE if no route is found
+ * see ip_output_if() for more return values
+ */
+err_t
+ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
+ u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
+{
+ struct netif *netif;
+ err_t err;
+
+ /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
+ gets altered as the packet is passed down the stack */
+ LWIP_ASSERT("p->ref == 1", p->ref == 1);
+
+ if ((netif = ip_route(dest)) == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
+ IP_STATS_INC(ip.rterr);
+ return ERR_RTE;
+ }
+
+ NETIF_SET_HWADDRHINT(netif, addr_hint);
+ err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
+ NETIF_SET_HWADDRHINT(netif, NULL);
+
+ return err;
+}
+#endif /* LWIP_NETIF_HWADDRHINT*/
+
+#if IP_DEBUG
+/* Print an IP header by using LWIP_DEBUGF
+ * @param p an IP packet, p->payload pointing to the IP header
+ */
+void
+ip_debug_print(struct pbuf *p)
+{
+ struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
+
+ LWIP_UNUSED_ARG(iphdr);
+
+ LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n",
+ IPH_V(iphdr),
+ IPH_HL(iphdr),
+ IPH_TOS(iphdr),
+ ntohs(IPH_LEN(iphdr))));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" |%"U16_F"%"U16_F"%"U16_F"| %4"U16_F" | (id, flags, offset)\n",
+ ntohs(IPH_ID(iphdr)),
+ ntohs(IPH_OFFSET(iphdr)) >> 15 & 1,
+ ntohs(IPH_OFFSET(iphdr)) >> 14 & 1,
+ ntohs(IPH_OFFSET(iphdr)) >> 13 & 1,
+ ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | 0x%04"X16_F" | (ttl, proto, chksum)\n",
+ IPH_TTL(iphdr),
+ IPH_PROTO(iphdr),
+ ntohs(IPH_CHKSUM(iphdr))));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (src)\n",
+ ip4_addr1_16(&iphdr->src),
+ ip4_addr2_16(&iphdr->src),
+ ip4_addr3_16(&iphdr->src),
+ ip4_addr4_16(&iphdr->src)));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+ LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n",
+ ip4_addr1_16(&iphdr->dest),
+ ip4_addr2_16(&iphdr->dest),
+ ip4_addr3_16(&iphdr->dest),
+ ip4_addr4_16(&iphdr->dest)));
+ LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
+}
+#endif /* IP_DEBUG */
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-26 22:02:09 +0000