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Posted to commits@mynewt.apache.org by ma...@apache.org on 2016/09/30 00:31:02 UTC
[19/51] [abbrv] [partial] incubator-mynewt-core git commit:
net/ip/lwip_base; LwIP.
http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/core/ipv4/igmp.c
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/core/ipv4/igmp.c b/net/ip/lwip_base/src/core/ipv4/igmp.c
new file mode 100644
index 0000000..f3db591
--- /dev/null
+++ b/net/ip/lwip_base/src/core/ipv4/igmp.c
@@ -0,0 +1,785 @@
+/**
+ * @file
+ * IGMP - Internet Group Management Protocol
+ *
+ * @defgroup igmp IGMP
+ * @ingroup ip4
+ * To be called from TCPIP thread
+ */
+
+/*
+ * Copyright (c) 2002 CITEL Technologies Ltd.
+ * 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. Neither the name of CITEL Technologies Ltd nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``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 CITEL TECHNOLOGIES OR CONTRIBUTORS 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 a contribution to the lwIP TCP/IP stack.
+ * The Swedish Institute of Computer Science and Adam Dunkels
+ * are specifically granted permission to redistribute this
+ * source code.
+*/
+
+/*-------------------------------------------------------------
+Note 1)
+Although the rfc requires V1 AND V2 capability
+we will only support v2 since now V1 is very old (August 1989)
+V1 can be added if required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 2)
+A query for a specific group address (as opposed to ALLHOSTS)
+has now been implemented as I am unsure if it is required
+
+a debug print and statistic have been implemented to
+show this up.
+-------------------------------------------------------------
+-------------------------------------------------------------
+Note 3)
+The router alert rfc 2113 is implemented in outgoing packets
+but not checked rigorously incoming
+-------------------------------------------------------------
+Steve Reynolds
+------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * RFC 988 - Host extensions for IP multicasting - V0
+ * RFC 1054 - Host extensions for IP multicasting -
+ * RFC 1112 - Host extensions for IP multicasting - V1
+ * RFC 2236 - Internet Group Management Protocol, Version 2 - V2 <- this code is based on this RFC (it's the "de facto" standard)
+ * RFC 3376 - Internet Group Management Protocol, Version 3 - V3
+ * RFC 4604 - Using Internet Group Management Protocol Version 3... - V3+
+ * RFC 2113 - IP Router Alert Option -
+ *----------------------------------------------------------------------------*/
+
+/*-----------------------------------------------------------------------------
+ * Includes
+ *----------------------------------------------------------------------------*/
+
+#include "lwip/opt.h"
+
+#if LWIP_IPV4 && LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
+
+#include "lwip/igmp.h"
+#include "lwip/debug.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/netif.h"
+#include "lwip/stats.h"
+#include "lwip/prot/igmp.h"
+
+#include "string.h"
+
+static struct igmp_group *igmp_lookup_group(struct netif *ifp, const ip4_addr_t *addr);
+static err_t igmp_remove_group(struct netif* netif, struct igmp_group *group);
+static void igmp_timeout(struct netif *netif, struct igmp_group *group);
+static void igmp_start_timer(struct igmp_group *group, u8_t max_time);
+static void igmp_delaying_member(struct igmp_group *group, u8_t maxresp);
+static err_t igmp_ip_output_if(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest, struct netif *netif);
+static void igmp_send(struct netif *netif, struct igmp_group *group, u8_t type);
+
+static ip4_addr_t allsystems;
+static ip4_addr_t allrouters;
+
+/**
+ * Initialize the IGMP module
+ */
+void
+igmp_init(void)
+{
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
+
+ IP4_ADDR(&allsystems, 224, 0, 0, 1);
+ IP4_ADDR(&allrouters, 224, 0, 0, 2);
+}
+
+/**
+ * Start IGMP processing on interface
+ *
+ * @param netif network interface on which start IGMP processing
+ */
+err_t
+igmp_start(struct netif *netif)
+{
+ struct igmp_group* group;
+
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %p\n", (void*)netif));
+
+ group = igmp_lookup_group(netif, &allsystems);
+
+ if (group != NULL) {
+ group->group_state = IGMP_GROUP_IDLE_MEMBER;
+ group->use++;
+
+ /* Allow the igmp messages at the MAC level */
+ if (netif->igmp_mac_filter != NULL) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
+ ip4_addr_debug_print_val(IGMP_DEBUG, allsystems);
+ LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void*)netif));
+ netif->igmp_mac_filter(netif, &allsystems, NETIF_ADD_MAC_FILTER);
+ }
+
+ return ERR_OK;
+ }
+
+ return ERR_MEM;
+}
+
+/**
+ * Stop IGMP processing on interface
+ *
+ * @param netif network interface on which stop IGMP processing
+ */
+err_t
+igmp_stop(struct netif *netif)
+{
+ struct igmp_group *group = netif_igmp_data(netif);
+
+ netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_IGMP, NULL);
+
+ while (group != NULL) {
+ struct igmp_group *next = group->next; /* avoid use-after-free below */
+
+ /* disable the group at the MAC level */
+ if (netif->igmp_mac_filter != NULL) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
+ ip4_addr_debug_print(IGMP_DEBUG, &group->group_address);
+ LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void*)netif));
+ netif->igmp_mac_filter(netif, &(group->group_address), NETIF_DEL_MAC_FILTER);
+ }
+
+ /* free group */
+ memp_free(MEMP_IGMP_GROUP, group);
+
+ /* move to "next" */
+ group = next;
+ }
+ return ERR_OK;
+}
+
+/**
+ * Report IGMP memberships for this interface
+ *
+ * @param netif network interface on which report IGMP memberships
+ */
+void
+igmp_report_groups(struct netif *netif)
+{
+ struct igmp_group *group = netif_igmp_data(netif);
+
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %p\n", (void*)netif));
+
+ while (group != NULL) {
+ if (!(ip4_addr_cmp(&(group->group_address), &allsystems))) {
+ igmp_delaying_member(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+ }
+ group = group->next;
+ }
+}
+
+/**
+ * Search for a group in the global igmp_group_list
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search for
+ * @return a struct igmp_group* if the group has been found,
+ * NULL if the group wasn't found.
+ */
+struct igmp_group *
+igmp_lookfor_group(struct netif *ifp, const ip4_addr_t *addr)
+{
+ struct igmp_group *group = netif_igmp_data(ifp);
+
+ while (group != NULL) {
+ if (ip4_addr_cmp(&(group->group_address), addr)) {
+ return group;
+ }
+ group = group->next;
+ }
+
+ /* to be clearer, we return NULL here instead of
+ * 'group' (which is also NULL at this point).
+ */
+ return NULL;
+}
+
+/**
+ * Search for a specific igmp group and create a new one if not found-
+ *
+ * @param ifp the network interface for which to look
+ * @param addr the group ip address to search
+ * @return a struct igmp_group*,
+ * NULL on memory error.
+ */
+struct igmp_group *
+igmp_lookup_group(struct netif *ifp, const ip4_addr_t *addr)
+{
+ struct igmp_group *group;
+
+ /* Search if the group already exists */
+ group = igmp_lookfor_group(ifp, addr);
+ if (group != NULL) {
+ /* Group already exists. */
+ return group;
+ }
+
+ /* Group doesn't exist yet, create a new one */
+ group = (struct igmp_group *)memp_malloc(MEMP_IGMP_GROUP);
+ if (group != NULL) {
+ ip4_addr_set(&(group->group_address), addr);
+ group->timer = 0; /* Not running */
+ group->group_state = IGMP_GROUP_NON_MEMBER;
+ group->last_reporter_flag = 0;
+ group->use = 0;
+ group->next = netif_igmp_data(ifp);
+
+ netif_set_client_data(ifp, LWIP_NETIF_CLIENT_DATA_INDEX_IGMP, group);
+ }
+
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group?"":"impossible to ")));
+ ip4_addr_debug_print(IGMP_DEBUG, addr);
+ LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void*)ifp));
+
+ return group;
+}
+
+/**
+ * Remove a group in the global igmp_group_list, but don't free it yet
+ *
+ * @param group the group to remove from the global igmp_group_list
+ * @return ERR_OK if group was removed from the list, an err_t otherwise
+ */
+static err_t
+igmp_remove_group(struct netif* netif, struct igmp_group *group)
+{
+ err_t err = ERR_OK;
+
+ /* Is it the first group? */
+ if (netif_igmp_data(netif) == group) {
+ netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_IGMP, group->next);
+ } else {
+ /* look for group further down the list */
+ struct igmp_group *tmpGroup;
+ for (tmpGroup = netif_igmp_data(netif); tmpGroup != NULL; tmpGroup = tmpGroup->next) {
+ if (tmpGroup->next == group) {
+ tmpGroup->next = group->next;
+ break;
+ }
+ }
+ /* Group not found in the global igmp_group_list */
+ if (tmpGroup == NULL) {
+ err = ERR_ARG;
+ }
+ }
+
+ return err;
+}
+
+/**
+ * Called from ip_input() if a new IGMP packet is received.
+ *
+ * @param p received igmp packet, p->payload pointing to the igmp header
+ * @param inp network interface on which the packet was received
+ * @param dest destination ip address of the igmp packet
+ */
+void
+igmp_input(struct pbuf *p, struct netif *inp, const ip4_addr_t *dest)
+{
+ struct igmp_msg* igmp;
+ struct igmp_group* group;
+ struct igmp_group* groupref;
+
+ IGMP_STATS_INC(igmp.recv);
+
+ /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */
+ if (p->len < IGMP_MINLEN) {
+ pbuf_free(p);
+ IGMP_STATS_INC(igmp.lenerr);
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
+ return;
+ }
+
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
+ ip4_addr_debug_print(IGMP_DEBUG, &(ip4_current_header()->src));
+ LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
+ ip4_addr_debug_print(IGMP_DEBUG, &(ip4_current_header()->dest));
+ LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void*)inp));
+
+ /* Now calculate and check the checksum */
+ igmp = (struct igmp_msg *)p->payload;
+ if (inet_chksum(igmp, p->len)) {
+ pbuf_free(p);
+ IGMP_STATS_INC(igmp.chkerr);
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
+ return;
+ }
+
+ /* Packet is ok so find an existing group */
+ group = igmp_lookfor_group(inp, dest); /* use the destination IP address of incoming packet */
+
+ /* If group can be found or create... */
+ if (!group) {
+ pbuf_free(p);
+ IGMP_STATS_INC(igmp.drop);
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
+ return;
+ }
+
+ /* NOW ACT ON THE INCOMING MESSAGE TYPE... */
+ switch (igmp->igmp_msgtype) {
+ case IGMP_MEMB_QUERY:
+ /* IGMP_MEMB_QUERY to the "all systems" address ? */
+ if ((ip4_addr_cmp(dest, &allsystems)) && ip4_addr_isany(&igmp->igmp_group_address)) {
+ /* THIS IS THE GENERAL QUERY */
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: General IGMP_MEMB_QUERY on \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+
+ if (igmp->igmp_maxresp == 0) {
+ IGMP_STATS_INC(igmp.rx_v1);
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
+ igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
+ } else {
+ IGMP_STATS_INC(igmp.rx_general);
+ }
+
+ groupref = netif_igmp_data(inp);
+ while (groupref) {
+ /* Do not send messages on the all systems group address! */
+ if (!(ip4_addr_cmp(&(groupref->group_address), &allsystems))) {
+ igmp_delaying_member(groupref, igmp->igmp_maxresp);
+ }
+ groupref = groupref->next;
+ }
+ } else {
+ /* IGMP_MEMB_QUERY to a specific group ? */
+ if (!ip4_addr_isany(&igmp->igmp_group_address)) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
+ ip4_addr_debug_print(IGMP_DEBUG, &igmp->igmp_group_address);
+ if (ip4_addr_cmp(dest, &allsystems)) {
+ ip4_addr_t groupaddr;
+ LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+ /* we first need to re-look for the group since we used dest last time */
+ ip4_addr_copy(groupaddr, igmp->igmp_group_address);
+ group = igmp_lookfor_group(inp, &groupaddr);
+ } else {
+ LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
+ }
+
+ if (group != NULL) {
+ IGMP_STATS_INC(igmp.rx_group);
+ igmp_delaying_member(group, igmp->igmp_maxresp);
+ } else {
+ IGMP_STATS_INC(igmp.drop);
+ }
+ } else {
+ IGMP_STATS_INC(igmp.proterr);
+ }
+ }
+ break;
+ case IGMP_V2_MEMB_REPORT:
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
+ IGMP_STATS_INC(igmp.rx_report);
+ if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
+ /* This is on a specific group we have already looked up */
+ group->timer = 0; /* stopped */
+ group->group_state = IGMP_GROUP_IDLE_MEMBER;
+ group->last_reporter_flag = 0;
+ }
+ break;
+ default:
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %d in state %d on group %p on if %p\n",
+ igmp->igmp_msgtype, group->group_state, (void*)&group, (void*)inp));
+ IGMP_STATS_INC(igmp.proterr);
+ break;
+ }
+
+ pbuf_free(p);
+ return;
+}
+
+/**
+ * @ingroup igmp
+ * Join a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should join a new group
+ * @param groupaddr the ip address of the group which to join
+ * @return ERR_OK if group was joined on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_joingroup(const ip4_addr_t *ifaddr, const ip4_addr_t *groupaddr)
+{
+ err_t err = ERR_VAL; /* no matching interface */
+ struct netif *netif;
+
+ /* make sure it is multicast address */
+ LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
+ LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+ /* loop through netif's */
+ netif = netif_list;
+ while (netif != NULL) {
+ /* Should we join this interface ? */
+ if ((netif->flags & NETIF_FLAG_IGMP) && ((ip4_addr_isany(ifaddr) || ip4_addr_cmp(netif_ip4_addr(netif), ifaddr)))) {
+ err = igmp_joingroup_netif(netif, groupaddr);
+ if (err != ERR_OK) {
+ /* Return an error even if some network interfaces are joined */
+ /** @todo undo any other netif already joined */
+ return err;
+ }
+ }
+ /* proceed to next network interface */
+ netif = netif->next;
+ }
+
+ return err;
+}
+
+/**
+ * @ingroup igmp
+ * Join a group on one network interface.
+ *
+ * @param netif the network interface which should join a new group
+ * @param groupaddr the ip address of the group which to join
+ * @return ERR_OK if group was joined on the netif, an err_t otherwise
+ */
+err_t
+igmp_joingroup_netif(struct netif *netif, const ip4_addr_t *groupaddr)
+{
+ struct igmp_group *group;
+
+ /* make sure it is multicast address */
+ LWIP_ERROR("igmp_joingroup_netif: attempt to join non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
+ LWIP_ERROR("igmp_joingroup_netif: attempt to join allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+ /* make sure it is an igmp-enabled netif */
+ LWIP_ERROR("igmp_joingroup_netif: attempt to join on non-IGMP netif", netif->flags & NETIF_FLAG_IGMP, return ERR_VAL;);
+
+ /* find group or create a new one if not found */
+ group = igmp_lookup_group(netif, groupaddr);
+
+ if (group != NULL) {
+ /* This should create a new group, check the state to make sure */
+ if (group->group_state != IGMP_GROUP_NON_MEMBER) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
+ } else {
+ /* OK - it was new group */
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: join to new group: "));
+ ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
+ LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+ /* If first use of the group, allow the group at the MAC level */
+ if ((group->use==0) && (netif->igmp_mac_filter != NULL)) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: igmp_mac_filter(ADD "));
+ ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
+ LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void*)netif));
+ netif->igmp_mac_filter(netif, groupaddr, NETIF_ADD_MAC_FILTER);
+ }
+
+ IGMP_STATS_INC(igmp.tx_join);
+ igmp_send(netif, group, IGMP_V2_MEMB_REPORT);
+
+ igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
+
+ /* Need to work out where this timer comes from */
+ group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+ }
+ /* Increment group use */
+ group->use++;
+ /* Join on this interface */
+ return ERR_OK;
+ } else {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup_netif: Not enough memory to join to group\n"));
+ return ERR_MEM;
+ }
+}
+
+/**
+ * @ingroup igmp
+ * Leave a group on one network interface.
+ *
+ * @param ifaddr ip address of the network interface which should leave a group
+ * @param groupaddr the ip address of the group which to leave
+ * @return ERR_OK if group was left on the netif(s), an err_t otherwise
+ */
+err_t
+igmp_leavegroup(const ip4_addr_t *ifaddr, const ip4_addr_t *groupaddr)
+{
+ err_t err = ERR_VAL; /* no matching interface */
+ struct netif *netif;
+
+ /* make sure it is multicast address */
+ LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
+ LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+ /* loop through netif's */
+ netif = netif_list;
+ while (netif != NULL) {
+ /* Should we leave this interface ? */
+ if ((netif->flags & NETIF_FLAG_IGMP) && ((ip4_addr_isany(ifaddr) || ip4_addr_cmp(netif_ip4_addr(netif), ifaddr)))) {
+ err_t res = igmp_leavegroup_netif(netif, groupaddr);
+ if (err != ERR_OK) {
+ /* Store this result if we have not yet gotten a success */
+ err = res;
+ }
+ }
+ /* proceed to next network interface */
+ netif = netif->next;
+ }
+
+ return err;
+}
+
+/**
+ * @ingroup igmp
+ * Leave a group on one network interface.
+ *
+ * @param netif the network interface which should leave a group
+ * @param groupaddr the ip address of the group which to leave
+ * @return ERR_OK if group was left on the netif, an err_t otherwise
+ */
+err_t
+igmp_leavegroup_netif(struct netif *netif, const ip4_addr_t *groupaddr)
+{
+ struct igmp_group *group;
+
+ /* make sure it is multicast address */
+ LWIP_ERROR("igmp_leavegroup_netif: attempt to leave non-multicast address", ip4_addr_ismulticast(groupaddr), return ERR_VAL;);
+ LWIP_ERROR("igmp_leavegroup_netif: attempt to leave allsystems address", (!ip4_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
+
+ /* make sure it is an igmp-enabled netif */
+ LWIP_ERROR("igmp_leavegroup_netif: attempt to leave on non-IGMP netif", netif->flags & NETIF_FLAG_IGMP, return ERR_VAL;);
+
+ /* find group */
+ group = igmp_lookfor_group(netif, groupaddr);
+
+ if (group != NULL) {
+ /* Only send a leave if the flag is set according to the state diagram */
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: Leaving group: "));
+ ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
+ LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
+
+ /* If there is no other use of the group */
+ if (group->use <= 1) {
+ /* Remove the group from the list */
+ igmp_remove_group(netif, group);
+
+ /* If we are the last reporter for this group */
+ if (group->last_reporter_flag) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: sending leaving group\n"));
+ IGMP_STATS_INC(igmp.tx_leave);
+ igmp_send(netif, group, IGMP_LEAVE_GROUP);
+ }
+
+ /* Disable the group at the MAC level */
+ if (netif->igmp_mac_filter != NULL) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: igmp_mac_filter(DEL "));
+ ip4_addr_debug_print(IGMP_DEBUG, groupaddr);
+ LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", (void*)netif));
+ netif->igmp_mac_filter(netif, groupaddr, NETIF_DEL_MAC_FILTER);
+ }
+
+ /* Free group struct */
+ memp_free(MEMP_IGMP_GROUP, group);
+ } else {
+ /* Decrement group use */
+ group->use--;
+ }
+ return ERR_OK;
+ } else {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup_netif: not member of group\n"));
+ return ERR_VAL;
+ }
+}
+
+/**
+ * The igmp timer function (both for NO_SYS=1 and =0)
+ * Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
+ */
+void
+igmp_tmr(void)
+{
+ struct netif *netif = netif_list;
+
+ while (netif != NULL) {
+ struct igmp_group *group = netif_igmp_data(netif);
+
+ while (group != NULL) {
+ if (group->timer > 0) {
+ group->timer--;
+ if (group->timer == 0) {
+ igmp_timeout(netif, group);
+ }
+ }
+ group = group->next;
+ }
+ netif = netif->next;
+ }
+}
+
+/**
+ * Called if a timeout for one group is reached.
+ * Sends a report for this group.
+ *
+ * @param group an igmp_group for which a timeout is reached
+ */
+static void
+igmp_timeout(struct netif *netif, struct igmp_group *group)
+{
+ /* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group
+ (unless it is the allsystems group) */
+ if ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
+ (!(ip4_addr_cmp(&(group->group_address), &allsystems)))) {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
+ ip4_addr_debug_print(IGMP_DEBUG, &(group->group_address));
+ LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", (void*)netif));
+
+ IGMP_STATS_INC(igmp.tx_report);
+ igmp_send(netif, group, IGMP_V2_MEMB_REPORT);
+ }
+}
+
+/**
+ * Start a timer for an igmp group
+ *
+ * @param group the igmp_group for which to start a timer
+ * @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
+ * every call to igmp_tmr())
+ */
+static void
+igmp_start_timer(struct igmp_group *group, u8_t max_time)
+{
+#ifdef LWIP_RAND
+ group->timer = max_time > 2 ? (LWIP_RAND() % max_time) : 1;
+#else /* LWIP_RAND */
+ /* ATTENTION: use this only if absolutely necessary! */
+ group->timer = max_time / 2;
+#endif /* LWIP_RAND */
+
+ if (group->timer == 0) {
+ group->timer = 1;
+ }
+}
+
+/**
+ * Delaying membership report for a group if necessary
+ *
+ * @param group the igmp_group for which "delaying" membership report
+ * @param maxresp query delay
+ */
+static void
+igmp_delaying_member(struct igmp_group *group, u8_t maxresp)
+{
+ if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) ||
+ ((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
+ ((group->timer == 0) || (maxresp < group->timer)))) {
+ igmp_start_timer(group, maxresp);
+ group->group_state = IGMP_GROUP_DELAYING_MEMBER;
+ }
+}
+
+
+/**
+ * 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.
+ *
+ * @param p the packet to send (p->payload points to the data, e.g. next
+ protocol header; if dest == LWIP_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 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
+ */
+static err_t
+igmp_ip_output_if(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest, struct netif *netif)
+{
+ /* This is the "router alert" option */
+ u16_t ra[2];
+ ra[0] = PP_HTONS(ROUTER_ALERT);
+ ra[1] = 0x0000; /* Router shall examine packet */
+ IGMP_STATS_INC(igmp.xmit);
+ return ip4_output_if_opt(p, src, dest, IGMP_TTL, 0, IP_PROTO_IGMP, netif, ra, ROUTER_ALERTLEN);
+}
+
+/**
+ * Send an igmp packet to a specific group.
+ *
+ * @param group the group to which to send the packet
+ * @param type the type of igmp packet to send
+ */
+static void
+igmp_send(struct netif *netif, struct igmp_group *group, u8_t type)
+{
+ struct pbuf* p = NULL;
+ struct igmp_msg* igmp = NULL;
+ ip4_addr_t src = *IP4_ADDR_ANY;
+ ip4_addr_t* dest = NULL;
+
+ /* IP header + "router alert" option + IGMP header */
+ p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
+
+ if (p) {
+ igmp = (struct igmp_msg *)p->payload;
+ LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
+ (p->len >= sizeof(struct igmp_msg)));
+ ip4_addr_copy(src, *netif_ip4_addr(netif));
+
+ if (type == IGMP_V2_MEMB_REPORT) {
+ dest = &(group->group_address);
+ ip4_addr_copy(igmp->igmp_group_address, group->group_address);
+ group->last_reporter_flag = 1; /* Remember we were the last to report */
+ } else {
+ if (type == IGMP_LEAVE_GROUP) {
+ dest = &allrouters;
+ ip4_addr_copy(igmp->igmp_group_address, group->group_address);
+ }
+ }
+
+ if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
+ igmp->igmp_msgtype = type;
+ igmp->igmp_maxresp = 0;
+ igmp->igmp_checksum = 0;
+ igmp->igmp_checksum = inet_chksum(igmp, IGMP_MINLEN);
+
+ igmp_ip_output_if(p, &src, dest, netif);
+ }
+
+ pbuf_free(p);
+ } else {
+ LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
+ IGMP_STATS_INC(igmp.memerr);
+ }
+}
+
+#endif /* LWIP_IPV4 && LWIP_IGMP */
http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/core/ipv4/ip4.c
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/core/ipv4/ip4.c b/net/ip/lwip_base/src/core/ipv4/ip4.c
new file mode 100644
index 0000000..27747ea
--- /dev/null
+++ b/net/ip/lwip_base/src/core/ipv4/ip4.c
@@ -0,0 +1,1073 @@
+/**
+ * @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 <ad...@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_IPV4
+
+#include "lwip/ip.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/ip4_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/priv/tcp_priv.h"
+#include "lwip/autoip.h"
+#include "lwip/stats.h"
+#include "lwip/prot/dhcp.h"
+
+#include <string.h>
+
+/** 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
+#if LWIP_CHECKSUM_CTRL_PER_NETIF
+#define LWIP_INLINE_IP_CHKSUM 0
+#else /* LWIP_CHECKSUM_CTRL_PER_NETIF */
+#define LWIP_INLINE_IP_CHKSUM 1
+#endif /* LWIP_CHECKSUM_CTRL_PER_NETIF */
+#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(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 */
+
+/** The IP header ID of the next outgoing IP packet */
+static u16_t ip_id;
+
+#if LWIP_MULTICAST_TX_OPTIONS
+/** The default netif used for multicast */
+static struct netif* ip4_default_multicast_netif;
+
+/**
+ * @ingroup ip4
+ * Set a default netif for IPv4 multicast. */
+void
+ip4_set_default_multicast_netif(struct netif* default_multicast_netif)
+{
+ ip4_default_multicast_netif = default_multicast_netif;
+}
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
+
+#ifdef LWIP_HOOK_IP4_ROUTE_SRC
+/**
+ * Source based IPv4 routing must be fully implemented in
+ * LWIP_HOOK_IP4_ROUTE_SRC(). This function only provides he parameters.
+ */
+struct netif *
+ip4_route_src(const ip4_addr_t *dest, const ip4_addr_t *src)
+{
+ if (src != NULL) {
+ /* when src==NULL, the hook is called from ip4_route(dest) */
+ struct netif *netif = LWIP_HOOK_IP4_ROUTE_SRC(dest, src);
+ if (netif != NULL) {
+ return netif;
+ }
+ }
+ return ip4_route(dest);
+}
+#endif /* LWIP_HOOK_IP4_ROUTE_SRC */
+
+/**
+ * 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 *
+ip4_route(const ip4_addr_t *dest)
+{
+ struct netif *netif;
+
+#if LWIP_MULTICAST_TX_OPTIONS
+ /* Use administratively selected interface for multicast by default */
+ if (ip4_addr_ismulticast(dest) && ip4_default_multicast_netif) {
+ return ip4_default_multicast_netif;
+ }
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
+
+ /* iterate through netifs */
+ for (netif = netif_list; netif != NULL; netif = netif->next) {
+ /* is the netif up, does it have a link and a valid address? */
+ if (netif_is_up(netif) && netif_is_link_up(netif) && !ip4_addr_isany_val(*netif_ip4_addr(netif))) {
+ /* network mask matches? */
+ if (ip4_addr_netcmp(dest, netif_ip4_addr(netif), netif_ip4_netmask(netif))) {
+ /* return netif on which to forward IP packet */
+ return netif;
+ }
+ /* gateway matches on a non broadcast interface? (i.e. peer in a point to point interface) */
+ if (((netif->flags & NETIF_FLAG_BROADCAST) == 0) && ip4_addr_cmp(dest, netif_ip4_gw(netif))) {
+ /* return netif on which to forward IP packet */
+ return netif;
+ }
+ }
+ }
+
+#if LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF
+ /* loopif is disabled, looopback traffic is passed through any netif */
+ if (ip4_addr_isloopback(dest)) {
+ /* don't check for link on loopback traffic */
+ if (netif_is_up(netif_default)) {
+ return netif_default;
+ }
+ /* default netif is not up, just use any netif for loopback traffic */
+ for (netif = netif_list; netif != NULL; netif = netif->next) {
+ if (netif_is_up(netif)) {
+ return netif;
+ }
+ }
+ return NULL;
+ }
+#endif /* LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF */
+
+#ifdef LWIP_HOOK_IP4_ROUTE_SRC
+ netif = LWIP_HOOK_IP4_ROUTE_SRC(dest, NULL);
+ if (netif != NULL) {
+ return netif;
+ }
+#elif defined(LWIP_HOOK_IP4_ROUTE)
+ netif = LWIP_HOOK_IP4_ROUTE(dest);
+ if (netif != NULL) {
+ return netif;
+ }
+#endif
+
+ if ((netif_default == NULL) || !netif_is_up(netif_default) || !netif_is_link_up(netif_default) ||
+ ip4_addr_isany_val(*netif_ip4_addr(netif_default))) {
+ /* No matching netif found and default netif is not usable.
+ If this is not good enough for you, use LWIP_HOOK_IP4_ROUTE() */
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip4_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);
+ MIB2_STATS_INC(mib2.ipoutnoroutes);
+ return NULL;
+ }
+
+ 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
+ip4_canforward(struct pbuf *p)
+{
+ u32_t addr = htonl(ip4_addr_get_u32(ip4_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
+ */
+static void
+ip4_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
+{
+ struct netif *netif;
+
+ PERF_START;
+ LWIP_UNUSED_ARG(inp);
+
+ if (!ip4_canforward(p)) {
+ goto return_noroute;
+ }
+
+ /* RFC3927 2.7: do not forward link-local addresses */
+ if (ip4_addr_islinklocal(ip4_current_dest_addr())) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(ip4_current_dest_addr()), ip4_addr2_16(ip4_current_dest_addr()),
+ ip4_addr3_16(ip4_current_dest_addr()), ip4_addr4_16(ip4_current_dest_addr())));
+ goto return_noroute;
+ }
+
+ /* Find network interface where to forward this IP packet to. */
+ netif = ip4_route_src(ip4_current_dest_addr(), ip4_current_src_addr());
+ if (netif == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
+ ip4_addr1_16(ip4_current_dest_addr()), ip4_addr2_16(ip4_current_dest_addr()),
+ ip4_addr3_16(ip4_current_dest_addr()), ip4_addr4_16(ip4_current_dest_addr())));
+ /* @todo: send ICMP_DUR_NET? */
+ goto return_noroute;
+ }
+#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, ("ip4_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) {
+ MIB2_STATS_INC(mib2.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;
+ }
+
+ /* 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, ("ip4_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
+ ip4_addr1_16(ip4_current_dest_addr()), ip4_addr2_16(ip4_current_dest_addr()),
+ ip4_addr3_16(ip4_current_dest_addr()), ip4_addr4_16(ip4_current_dest_addr())));
+
+ IP_STATS_INC(ip.fw);
+ MIB2_STATS_INC(mib2.ipforwdatagrams);
+ IP_STATS_INC(ip.xmit);
+
+ PERF_STOP("ip4_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
+ ip4_frag(p, netif, ip4_current_dest_addr());
+#else /* IP_FRAG */
+ /* @todo: send ICMP Destination Unreachable code 13 "Communication administratively prohibited"? */
+#endif /* IP_FRAG */
+ } else {
+#if LWIP_ICMP
+ /* send ICMP Destination Unreachable code 4: "Fragmentation Needed and DF Set" */
+ icmp_dest_unreach(p, ICMP_DUR_FRAG);
+#endif /* LWIP_ICMP */
+ }
+ return;
+ }
+ /* transmit pbuf on chosen interface */
+ netif->output(netif, p, ip4_current_dest_addr());
+ return;
+return_noroute:
+ MIB2_STATS_INC(mib2.ipoutnoroutes);
+}
+#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
+ip4_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 || LWIP_IGMP
+ int check_ip_src = 1;
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING || LWIP_IGMP */
+
+ IP_STATS_INC(ip.recv);
+ MIB2_STATS_INC(mib2.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", (u16_t)IPH_V(iphdr)));
+ ip4_debug_print(p);
+ pbuf_free(p);
+ IP_STATS_INC(ip.err);
+ IP_STATS_INC(ip.drop);
+ MIB2_STATS_INC(mib2.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));
+
+ /* Trim pbuf. This is especially required for packets < 60 bytes. */
+ if (iphdr_len < p->tot_len) {
+ pbuf_realloc(p, iphdr_len);
+ }
+
+ /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
+ if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len) || (iphdr_hlen < IP_HLEN)) {
+ if (iphdr_hlen < IP_HLEN) {
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
+ ("ip4_input: short IP header (%"U16_F" bytes) received, IP packet dropped\n", iphdr_hlen));
+ }
+ 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);
+ MIB2_STATS_INC(mib2.ipindiscards);
+ return ERR_OK;
+ }
+
+ /* verify checksum */
+#if CHECKSUM_CHECK_IP
+ IF__NETIF_CHECKSUM_ENABLED(inp, NETIF_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)));
+ ip4_debug_print(p);
+ pbuf_free(p);
+ IP_STATS_INC(ip.chkerr);
+ IP_STATS_INC(ip.drop);
+ MIB2_STATS_INC(mib2.ipinhdrerrors);
+ return ERR_OK;
+ }
+ }
+#endif
+
+ /* copy IP addresses to aligned ip_addr_t */
+ ip_addr_copy_from_ip4(ip_data.current_iphdr_dest, iphdr->dest);
+ ip_addr_copy_from_ip4(ip_data.current_iphdr_src, iphdr->src);
+
+ /* match packet against an interface, i.e. is this packet for us? */
+ if (ip4_addr_ismulticast(ip4_current_dest_addr())) {
+#if LWIP_IGMP
+ if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, ip4_current_dest_addr()))) {
+ /* IGMP snooping switches need 0.0.0.0 to be allowed as source address (RFC 4541) */
+ ip4_addr_t allsystems;
+ IP4_ADDR(&allsystems, 224, 0, 0, 1);
+ if (ip4_addr_cmp(ip4_current_dest_addr(), &allsystems) &&
+ ip4_addr_isany(ip4_current_src_addr())) {
+ check_ip_src = 0;
+ }
+ netif = inp;
+ } else {
+ netif = NULL;
+ }
+#else /* LWIP_IGMP */
+ if ((netif_is_up(inp)) && (!ip4_addr_isany_val(*netif_ip4_addr(inp)))) {
+ netif = inp;
+ } else {
+ netif = NULL;
+ }
+#endif /* LWIP_IGMP */
+ } else {
+ /* 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 0x%"X32_F" netif->ip_addr 0x%"X32_F" (0x%"X32_F", 0x%"X32_F", 0x%"X32_F")\n",
+ ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(netif_ip4_addr(netif)),
+ ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(netif_ip4_netmask(netif)),
+ ip4_addr_get_u32(netif_ip4_addr(netif)) & ip4_addr_get_u32(netif_ip4_netmask(netif)),
+ ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(netif_ip4_netmask(netif))));
+
+ /* interface is up and configured? */
+ if ((netif_is_up(netif)) && (!ip4_addr_isany_val(*netif_ip4_addr(netif)))) {
+ /* unicast to this interface address? */
+ if (ip4_addr_cmp(ip4_current_dest_addr(), netif_ip4_addr(netif)) ||
+ /* or broadcast on this interface network address? */
+ ip4_addr_isbroadcast(ip4_current_dest_addr(), netif)
+#if LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF
+ || (ip4_addr_get_u32(ip4_current_dest_addr()) == PP_HTONL(IPADDR_LOOPBACK))
+#endif /* LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF */
+ ) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_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 (autoip_accept_packet(netif, ip4_current_dest_addr())) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_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, ("ip4_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, ("ip4_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 LWIP_IGMP || IP_ACCEPT_LINK_LAYER_ADDRESSING
+ if (check_ip_src
+#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) */
+ && !ip4_addr_isany_val(*ip4_current_src_addr())
+#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
+ )
+#endif /* LWIP_IGMP || IP_ACCEPT_LINK_LAYER_ADDRESSING */
+ {
+ if ((ip4_addr_isbroadcast(ip4_current_src_addr(), inp)) ||
+ (ip4_addr_ismulticast(ip4_current_src_addr()))) {
+ /* packet source is not valid */
+ LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip4_input: packet source is not valid.\n"));
+ /* free (drop) packet pbufs */
+ pbuf_free(p);
+ IP_STATS_INC(ip.drop);
+ MIB2_STATS_INC(mib2.ipinaddrerrors);
+ MIB2_STATS_INC(mib2.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, ("ip4_input: packet not for us.\n"));
+#if IP_FORWARD
+ /* non-broadcast packet? */
+ if (!ip4_addr_isbroadcast(ip4_current_dest_addr(), inp)) {
+ /* try to forward IP packet on (other) interfaces */
+ ip4_forward(p, iphdr, inp);
+ } else
+#endif /* IP_FORWARD */
+ {
+ MIB2_STATS_INC(mib2.ipinaddrerrors);
+ MIB2_STATS_INC(mib2.ipindiscards);
+ }
+ 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 ip4_reass()\n",
+ ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), (u16_t)!!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (u16_t)((ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8)));
+ /* reassemble the packet*/
+ p = ip4_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 */
+ MIB2_STATS_INC(mib2.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 */
+ MIB2_STATS_INC(mib2.ipinunknownprotos);
+ return ERR_OK;
+ }
+#endif /* IP_OPTIONS_ALLOWED == 0 */
+
+ /* send to upper layers */
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_input: \n"));
+ ip4_debug_print(p);
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
+
+ ip_data.current_netif = netif;
+ ip_data.current_input_netif = inp;
+ ip_data.current_ip4_header = iphdr;
+ ip_data.current_ip_header_tot_len = IPH_HL(iphdr) * 4;
+
+#if LWIP_RAW
+ /* raw input did not eat the packet? */
+ if (raw_input(p, inp) == 0)
+#endif /* LWIP_RAW */
+ {
+ pbuf_header(p, -(s16_t)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 */
+ MIB2_STATS_INC(mib2.ipindelivers);
+ udp_input(p, inp);
+ break;
+#endif /* LWIP_UDP */
+#if LWIP_TCP
+ case IP_PROTO_TCP:
+ MIB2_STATS_INC(mib2.ipindelivers);
+ tcp_input(p, inp);
+ break;
+#endif /* LWIP_TCP */
+#if LWIP_ICMP
+ case IP_PROTO_ICMP:
+ MIB2_STATS_INC(mib2.ipindelivers);
+ icmp_input(p, inp);
+ break;
+#endif /* LWIP_ICMP */
+#if LWIP_IGMP
+ case IP_PROTO_IGMP:
+ igmp_input(p, inp, ip4_current_dest_addr());
+ break;
+#endif /* LWIP_IGMP */
+ default:
+#if LWIP_ICMP
+ /* send ICMP destination protocol unreachable unless is was a broadcast */
+ if (!ip4_addr_isbroadcast(ip4_current_dest_addr(), netif) &&
+ !ip4_addr_ismulticast(ip4_current_dest_addr())) {
+ pbuf_header_force(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", (u16_t)IPH_PROTO(iphdr)));
+
+ IP_STATS_INC(ip.proterr);
+ IP_STATS_INC(ip.drop);
+ MIB2_STATS_INC(mib2.ipinunknownprotos);
+ }
+ }
+
+ /* @todo: this is not really necessary... */
+ ip_data.current_netif = NULL;
+ ip_data.current_input_netif = NULL;
+ ip_data.current_ip4_header = NULL;
+ ip_data.current_ip_header_tot_len = 0;
+ ip4_addr_set_any(ip4_current_src_addr());
+ ip4_addr_set_any(ip4_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 LWIP_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 == LWIP_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
+ip4_output_if(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest,
+ u8_t ttl, u8_t tos,
+ u8_t proto, struct netif *netif)
+{
+#if IP_OPTIONS_SEND
+ return ip4_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
+ip4_output_if_opt(struct pbuf *p, const ip4_addr_t *src, const ip4_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 */
+ const ip4_addr_t *src_used = src;
+ if (dest != LWIP_IP_HDRINCL) {
+ if (ip4_addr_isany(src)) {
+ src_used = netif_ip4_addr(netif);
+ }
+ }
+
+#if IP_OPTIONS_SEND
+ return ip4_output_if_opt_src(p, src_used, dest, ttl, tos, proto, netif,
+ ip_options, optlen);
+#else /* IP_OPTIONS_SEND */
+ return ip4_output_if_src(p, src_used, dest, ttl, tos, proto, netif);
+#endif /* IP_OPTIONS_SEND */
+}
+
+/**
+ * Same as ip_output_if() but 'src' address is not replaced by netif address
+ * when it is 'any'.
+ */
+err_t
+ip4_output_if_src(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest,
+ u8_t ttl, u8_t tos,
+ u8_t proto, struct netif *netif)
+{
+#if IP_OPTIONS_SEND
+ return ip4_output_if_opt_src(p, src, dest, ttl, tos, proto, netif, NULL, 0);
+}
+
+/**
+ * Same as ip_output_if_opt() but 'src' address is not replaced by netif address
+ * when it is 'any'.
+ */
+err_t
+ip4_output_if_opt_src(struct pbuf *p, const ip4_addr_t *src, const ip4_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;
+ ip4_addr_t dest_addr;
+#if CHECKSUM_GEN_IP_INLINE
+ u32_t chk_sum = 0;
+#endif /* CHECKSUM_GEN_IP_INLINE */
+
+ LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
+
+ MIB2_STATS_INC(mib2.ipoutrequests);
+
+ /* Should the IP header be generated or is it already included in p? */
+ if (dest != LWIP_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, ("ip4_output_if_opt: not enough room for IP options in pbuf\n"));
+ IP_STATS_INC(ip.err);
+ MIB2_STATS_INC(mib2.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, ("ip4_output: not enough room for IP header in pbuf\n"));
+
+ IP_STATS_INC(ip.err);
+ MIB2_STATS_INC(mib2.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 */
+ ip4_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 (src == NULL) {
+ ip4_addr_copy(iphdr->src, *IP4_ADDR_ANY);
+ } else {
+ /* src cannot be NULL here */
+ ip4_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;
+ IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_IP) {
+ iphdr->_chksum = (u16_t)chk_sum; /* network order */
+ }
+#if LWIP_CHECKSUM_CTRL_PER_NETIF
+ else {
+ IPH_CHKSUM_SET(iphdr, 0);
+ }
+#endif /* LWIP_CHECKSUM_CTRL_PER_NETIF*/
+#else /* CHECKSUM_GEN_IP_INLINE */
+ IPH_CHKSUM_SET(iphdr, 0);
+#if CHECKSUM_GEN_IP
+ IF__NETIF_CHECKSUM_ENABLED(netif, NETIF_CHECKSUM_GEN_IP) {
+ IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
+ }
+#endif /* CHECKSUM_GEN_IP */
+#endif /* CHECKSUM_GEN_IP_INLINE */
+ } else {
+ /* IP header already included in p */
+ iphdr = (struct ip_hdr *)p->payload;
+ ip4_addr_copy(dest_addr, iphdr->dest);
+ dest = &dest_addr;
+ }
+
+ IP_STATS_INC(ip.xmit);
+
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], (u16_t)netif->num));
+ ip4_debug_print(p);
+
+#if ENABLE_LOOPBACK
+ if (ip4_addr_cmp(dest, netif_ip4_addr(netif))
+#if !LWIP_HAVE_LOOPIF
+ || ip4_addr_isloopback(dest)
+#endif /* !LWIP_HAVE_LOOPIF */
+ ) {
+ /* Packet to self, enqueue it for loopback */
+ LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
+ return netif_loop_output(netif, p);
+ }
+#if LWIP_MULTICAST_TX_OPTIONS
+ if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
+ netif_loop_output(netif, p);
+ }
+#endif /* LWIP_MULTICAST_TX_OPTIONS */
+#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 ip4_frag(p, netif, dest);
+ }
+#endif /* IP_FRAG */
+
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_output_if: call 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 == LWIP_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
+ip4_output(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest,
+ u8_t ttl, u8_t tos, u8_t proto)
+{
+ struct netif *netif;
+
+ LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
+
+ if ((netif = ip4_route_src(dest, src)) == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_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 ip4_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 == LWIP_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
+ip4_output_hinted(struct pbuf *p, const ip4_addr_t *src, const ip4_addr_t *dest,
+ u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
+{
+ struct netif *netif;
+ err_t err;
+
+ LWIP_IP_CHECK_PBUF_REF_COUNT_FOR_TX(p);
+
+ if ((netif = ip4_route_src(dest, src)) == NULL) {
+ LWIP_DEBUGF(IP_DEBUG, ("ip4_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 = ip4_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
+ip4_debug_print(struct pbuf *p)
+{
+ struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
+
+ 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",
+ (u16_t)IPH_V(iphdr),
+ (u16_t)IPH_HL(iphdr),
+ (u16_t)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)),
+ (u16_t)(ntohs(IPH_OFFSET(iphdr)) >> 15 & 1),
+ (u16_t)(ntohs(IPH_OFFSET(iphdr)) >> 14 & 1),
+ (u16_t)(ntohs(IPH_OFFSET(iphdr)) >> 13 & 1),
+ (u16_t)(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",
+ (u16_t)IPH_TTL(iphdr),
+ (u16_t)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 */
+
+#endif /* LWIP_IPV4 */
http://git-wip-us.apache.org/repos/asf/incubator-mynewt-core/blob/f5a0f2a0/net/ip/lwip_base/src/core/ipv4/ip4_addr.c
----------------------------------------------------------------------
diff --git a/net/ip/lwip_base/src/core/ipv4/ip4_addr.c b/net/ip/lwip_base/src/core/ipv4/ip4_addr.c
new file mode 100644
index 0000000..7fe35c9
--- /dev/null
+++ b/net/ip/lwip_base/src/core/ipv4/ip4_addr.c
@@ -0,0 +1,331 @@
+/**
+ * @file
+ * This is the IPv4 address tools implementation.
+ *
+ */
+
+/*
+ * 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 <ad...@sics.se>
+ *
+ */
+
+#include "lwip/opt.h"
+
+#if LWIP_IPV4
+
+#include "lwip/ip_addr.h"
+#include "lwip/netif.h"
+
+/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
+const ip_addr_t ip_addr_any = IPADDR4_INIT(IPADDR_ANY);
+const ip_addr_t ip_addr_broadcast = IPADDR4_INIT(IPADDR_BROADCAST);
+
+/**
+ * Determine if an address is a broadcast address on a network interface
+ *
+ * @param addr address to be checked
+ * @param netif the network interface against which the address is checked
+ * @return returns non-zero if the address is a broadcast address
+ */
+u8_t
+ip4_addr_isbroadcast_u32(u32_t addr, const struct netif *netif)
+{
+ ip4_addr_t ipaddr;
+ ip4_addr_set_u32(&ipaddr, addr);
+
+ /* all ones (broadcast) or all zeroes (old skool broadcast) */
+ if ((~addr == IPADDR_ANY) ||
+ (addr == IPADDR_ANY)) {
+ return 1;
+ /* no broadcast support on this network interface? */
+ } else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) {
+ /* the given address cannot be a broadcast address
+ * nor can we check against any broadcast addresses */
+ return 0;
+ /* address matches network interface address exactly? => no broadcast */
+ } else if (addr == ip4_addr_get_u32(netif_ip4_addr(netif))) {
+ return 0;
+ /* on the same (sub) network... */
+ } else if (ip4_addr_netcmp(&ipaddr, netif_ip4_addr(netif), netif_ip4_netmask(netif))
+ /* ...and host identifier bits are all ones? =>... */
+ && ((addr & ~ip4_addr_get_u32(netif_ip4_netmask(netif))) ==
+ (IPADDR_BROADCAST & ~ip4_addr_get_u32(netif_ip4_netmask(netif))))) {
+ /* => network broadcast address */
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+/** Checks if a netmask is valid (starting with ones, then only zeros)
+ *
+ * @param netmask the IPv4 netmask to check (in network byte order!)
+ * @return 1 if the netmask is valid, 0 if it is not
+ */
+u8_t
+ip4_addr_netmask_valid(u32_t netmask)
+{
+ u32_t mask;
+ u32_t nm_hostorder = lwip_htonl(netmask);
+
+ /* first, check for the first zero */
+ for (mask = 1UL << 31 ; mask != 0; mask >>= 1) {
+ if ((nm_hostorder & mask) == 0) {
+ break;
+ }
+ }
+ /* then check that there is no one */
+ for (; mask != 0; mask >>= 1) {
+ if ((nm_hostorder & mask) != 0) {
+ /* there is a one after the first zero -> invalid */
+ return 0;
+ }
+ }
+ /* no one after the first zero -> valid */
+ return 1;
+}
+
+/* Here for now until needed in other places in lwIP */
+#ifndef isprint
+#define in_range(c, lo, up) ((u8_t)c >= lo && (u8_t)c <= up)
+#define isprint(c) in_range(c, 0x20, 0x7f)
+#define isdigit(c) in_range(c, '0', '9')
+#define isxdigit(c) (isdigit(c) || in_range(c, 'a', 'f') || in_range(c, 'A', 'F'))
+#define islower(c) in_range(c, 'a', 'z')
+#define isspace(c) (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v')
+#endif
+
+/**
+ * Ascii internet address interpretation routine.
+ * The value returned is in network order.
+ *
+ * @param cp IP address in ascii representation (e.g. "127.0.0.1")
+ * @return ip address in network order
+ */
+u32_t
+ipaddr_addr(const char *cp)
+{
+ ip4_addr_t val;
+
+ if (ip4addr_aton(cp, &val)) {
+ return ip4_addr_get_u32(&val);
+ }
+ return (IPADDR_NONE);
+}
+
+/**
+ * Check whether "cp" is a valid ascii representation
+ * of an Internet address and convert to a binary address.
+ * Returns 1 if the address is valid, 0 if not.
+ * This replaces inet_addr, the return value from which
+ * cannot distinguish between failure and a local broadcast address.
+ *
+ * @param cp IP address in ascii representation (e.g. "127.0.0.1")
+ * @param addr pointer to which to save the ip address in network order
+ * @return 1 if cp could be converted to addr, 0 on failure
+ */
+int
+ip4addr_aton(const char *cp, ip4_addr_t *addr)
+{
+ u32_t val;
+ u8_t base;
+ char c;
+ u32_t parts[4];
+ u32_t *pp = parts;
+
+ c = *cp;
+ for (;;) {
+ /*
+ * Collect number up to ``.''.
+ * Values are specified as for C:
+ * 0x=hex, 0=octal, 1-9=decimal.
+ */
+ if (!isdigit(c)) {
+ return 0;
+ }
+ val = 0;
+ base = 10;
+ if (c == '0') {
+ c = *++cp;
+ if (c == 'x' || c == 'X') {
+ base = 16;
+ c = *++cp;
+ } else {
+ base = 8;
+ }
+ }
+ for (;;) {
+ if (isdigit(c)) {
+ val = (val * base) + (int)(c - '0');
+ c = *++cp;
+ } else if (base == 16 && isxdigit(c)) {
+ val = (val << 4) | (int)(c + 10 - (islower(c) ? 'a' : 'A'));
+ c = *++cp;
+ } else {
+ break;
+ }
+ }
+ if (c == '.') {
+ /*
+ * Internet format:
+ * a.b.c.d
+ * a.b.c (with c treated as 16 bits)
+ * a.b (with b treated as 24 bits)
+ */
+ if (pp >= parts + 3) {
+ return 0;
+ }
+ *pp++ = val;
+ c = *++cp;
+ } else {
+ break;
+ }
+ }
+ /*
+ * Check for trailing characters.
+ */
+ if (c != '\0' && !isspace(c)) {
+ return 0;
+ }
+ /*
+ * Concoct the address according to
+ * the number of parts specified.
+ */
+ switch (pp - parts + 1) {
+
+ case 0:
+ return 0; /* initial nondigit */
+
+ case 1: /* a -- 32 bits */
+ break;
+
+ case 2: /* a.b -- 8.24 bits */
+ if (val > 0xffffffUL) {
+ return 0;
+ }
+ if (parts[0] > 0xff) {
+ return 0;
+ }
+ val |= parts[0] << 24;
+ break;
+
+ case 3: /* a.b.c -- 8.8.16 bits */
+ if (val > 0xffff) {
+ return 0;
+ }
+ if ((parts[0] > 0xff) || (parts[1] > 0xff)) {
+ return 0;
+ }
+ val |= (parts[0] << 24) | (parts[1] << 16);
+ break;
+
+ case 4: /* a.b.c.d -- 8.8.8.8 bits */
+ if (val > 0xff) {
+ return 0;
+ }
+ if ((parts[0] > 0xff) || (parts[1] > 0xff) || (parts[2] > 0xff)) {
+ return 0;
+ }
+ val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
+ break;
+ default:
+ LWIP_ASSERT("unhandled", 0);
+ break;
+ }
+ if (addr) {
+ ip4_addr_set_u32(addr, htonl(val));
+ }
+ return 1;
+}
+
+/**
+ * Convert numeric IP address into decimal dotted ASCII representation.
+ * returns ptr to static buffer; not reentrant!
+ *
+ * @param addr ip address in network order to convert
+ * @return pointer to a global static (!) buffer that holds the ASCII
+ * representation of addr
+ */
+char*
+ip4addr_ntoa(const ip4_addr_t *addr)
+{
+ static char str[IP4ADDR_STRLEN_MAX];
+ return ip4addr_ntoa_r(addr, str, IP4ADDR_STRLEN_MAX);
+}
+
+/**
+ * Same as ipaddr_ntoa, but reentrant since a user-supplied buffer is used.
+ *
+ * @param addr ip address in network order to convert
+ * @param buf target buffer where the string is stored
+ * @param buflen length of buf
+ * @return either pointer to buf which now holds the ASCII
+ * representation of addr or NULL if buf was too small
+ */
+char*
+ip4addr_ntoa_r(const ip4_addr_t *addr, char *buf, int buflen)
+{
+ u32_t s_addr;
+ char inv[3];
+ char *rp;
+ u8_t *ap;
+ u8_t rem;
+ u8_t n;
+ u8_t i;
+ int len = 0;
+
+ s_addr = ip4_addr_get_u32(addr);
+
+ rp = buf;
+ ap = (u8_t *)&s_addr;
+ for (n = 0; n < 4; n++) {
+ i = 0;
+ do {
+ rem = *ap % (u8_t)10;
+ *ap /= (u8_t)10;
+ inv[i++] = '0' + rem;
+ } while (*ap);
+ while (i--) {
+ if (len++ >= buflen) {
+ return NULL;
+ }
+ *rp++ = inv[i];
+ }
+ if (len++ >= buflen) {
+ return NULL;
+ }
+ *rp++ = '.';
+ ap++;
+ }
+ *--rp = 0;
+ return buf;
+}
+
+#endif /* LWIP_IPV4 */