[164] | 1 | /**
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| 2 | * @file
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| 3 | * This is the IPv4 layer implementation for incoming and outgoing IP traffic.
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| 4 | *
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| 5 | * @see ip_frag.c
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| 6 | *
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| 7 | */
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| 8 |
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| 9 | /*
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| 10 | * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
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| 11 | * All rights reserved.
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| 12 | *
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| 13 | * Redistribution and use in source and binary forms, with or without modification,
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| 14 | * are permitted provided that the following conditions are met:
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| 15 | *
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| 16 | * 1. Redistributions of source code must retain the above copyright notice,
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| 17 | * this list of conditions and the following disclaimer.
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| 18 | * 2. Redistributions in binary form must reproduce the above copyright notice,
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| 19 | * this list of conditions and the following disclaimer in the documentation
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| 20 | * and/or other materials provided with the distribution.
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| 21 | * 3. The name of the author may not be used to endorse or promote products
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| 22 | * derived from this software without specific prior written permission.
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| 23 | *
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| 24 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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| 25 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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| 26 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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| 27 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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| 28 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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| 29 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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| 30 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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| 31 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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| 32 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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| 33 | * OF SUCH DAMAGE.
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| 34 | *
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| 35 | * This file is part of the lwIP TCP/IP stack.
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| 36 | *
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| 37 | * Author: Adam Dunkels <adam@sics.se>
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| 38 | *
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| 39 | */
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| 40 |
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| 41 | #include "lwip/opt.h"
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| 42 | #include "lwip/ip.h"
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| 43 | #include "lwip/def.h"
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| 44 | #include "lwip/mem.h"
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| 45 | #include "lwip/ip_frag.h"
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| 46 | #include "lwip/inet_chksum.h"
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| 47 | #include "lwip/netif.h"
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| 48 | #include "lwip/icmp.h"
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| 49 | #include "lwip/igmp.h"
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| 50 | #include "lwip/raw.h"
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| 51 | #include "lwip/udp.h"
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| 52 | #include "lwip/tcp_impl.h"
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| 53 | #include "lwip/snmp.h"
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| 54 | #include "lwip/dhcp.h"
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| 55 | #include "lwip/autoip.h"
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| 56 | #include "lwip/stats.h"
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| 57 | #include "arch/perf.h"
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| 58 |
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| 59 | #include <string.h>
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| 60 |
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| 61 | /** Set this to 0 in the rare case of wanting to call an extra function to
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| 62 | * generate the IP checksum (in contrast to calculating it on-the-fly). */
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| 63 | #ifndef LWIP_INLINE_IP_CHKSUM
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| 64 | #define LWIP_INLINE_IP_CHKSUM 1
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| 65 | #endif
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| 66 | #if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP
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| 67 | #define CHECKSUM_GEN_IP_INLINE 1
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| 68 | #else
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| 69 | #define CHECKSUM_GEN_IP_INLINE 0
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| 70 | #endif
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| 71 |
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| 72 | #if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT)
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| 73 | #define IP_ACCEPT_LINK_LAYER_ADDRESSING 1
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| 74 |
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| 75 | /** Some defines for DHCP to let link-layer-addressed packets through while the
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| 76 | * netif is down.
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| 77 | * To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT
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| 78 | * to return 1 if the port is accepted and 0 if the port is not accepted.
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| 79 | */
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| 80 | #if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT)
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| 81 | /* accept DHCP client port and custom port */
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| 82 | #define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \
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| 83 | || (LWIP_IP_ACCEPT_UDP_PORT(port)))
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| 84 | #elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
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| 85 | /* accept custom port only */
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| 86 | #define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(port))
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| 87 | #else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
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| 88 | /* accept DHCP client port only */
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| 89 | #define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT))
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| 90 | #endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
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| 91 |
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| 92 | #else /* LWIP_DHCP */
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| 93 | #define IP_ACCEPT_LINK_LAYER_ADDRESSING 0
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| 94 | #endif /* LWIP_DHCP */
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| 95 |
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| 96 | /**
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| 97 | * The interface that provided the packet for the current callback
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| 98 | * invocation.
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| 99 | */
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| 100 | struct netif *current_netif;
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| 101 |
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| 102 | /**
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| 103 | * Header of the input packet currently being processed.
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| 104 | */
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| 105 | const struct ip_hdr *current_header;
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| 106 | /** Source IP address of current_header */
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| 107 | ip_addr_t current_iphdr_src;
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| 108 | /** Destination IP address of current_header */
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| 109 | ip_addr_t current_iphdr_dest;
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| 110 |
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| 111 | /** The IP header ID of the next outgoing IP packet */
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| 112 | static u16_t ip_id;
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| 113 |
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| 114 | /**
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| 115 | * Finds the appropriate network interface for a given IP address. It
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| 116 | * searches the list of network interfaces linearly. A match is found
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| 117 | * if the masked IP address of the network interface equals the masked
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| 118 | * IP address given to the function.
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| 119 | *
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| 120 | * @param dest the destination IP address for which to find the route
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| 121 | * @return the netif on which to send to reach dest
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| 122 | */
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| 123 | struct netif *
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| 124 | ip_route(ip_addr_t *dest)
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| 125 | {
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| 126 | struct netif *netif;
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| 127 |
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| 128 | #ifdef LWIP_HOOK_IP4_ROUTE
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| 129 | netif = LWIP_HOOK_IP4_ROUTE(dest);
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| 130 | if (netif != NULL) {
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| 131 | return netif;
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| 132 | }
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| 133 | #endif
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| 134 |
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| 135 | /* iterate through netifs */
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| 136 | for (netif = netif_list; netif != NULL; netif = netif->next) {
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| 137 | /* network mask matches? */
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| 138 | if (netif_is_up(netif)) {
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| 139 | if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
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| 140 | /* return netif on which to forward IP packet */
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| 141 | return netif;
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| 142 | }
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| 143 | }
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| 144 | }
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| 145 | if ((netif_default == NULL) || (!netif_is_up(netif_default))) {
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| 146 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
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| 147 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
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| 148 | IP_STATS_INC(ip.rterr);
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| 149 | snmp_inc_ipoutnoroutes();
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| 150 | return NULL;
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| 151 | }
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| 152 | /* no matching netif found, use default netif */
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| 153 | return netif_default;
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| 154 | }
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| 155 |
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| 156 | #if IP_FORWARD
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| 157 | /**
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| 158 | * Determine whether an IP address is in a reserved set of addresses
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| 159 | * that may not be forwarded, or whether datagrams to that destination
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| 160 | * may be forwarded.
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| 161 | * @param p the packet to forward
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| 162 | * @param dest the destination IP address
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| 163 | * @return 1: can forward 0: discard
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| 164 | */
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| 165 | static int
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| 166 | ip_canforward(struct pbuf *p)
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| 167 | {
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| 168 | u32_t addr = ip4_addr_get_u32(ip_current_dest_addr());
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| 169 |
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| 170 | if (p->flags & PBUF_FLAG_LLBCAST) {
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| 171 | /* don't route link-layer broadcasts */
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| 172 | return 0;
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| 173 | }
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| 174 | if ((p->flags & PBUF_FLAG_LLMCAST) && !IP_MULTICAST(addr)) {
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| 175 | /* don't route link-layer multicasts unless the destination address is an IP
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| 176 | multicast address */
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| 177 | return 0;
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| 178 | }
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| 179 | if (IP_EXPERIMENTAL(addr)) {
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| 180 | return 0;
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| 181 | }
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| 182 | if (IP_CLASSA(addr)) {
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| 183 | u32_t net = addr & IP_CLASSA_NET;
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| 184 | if ((net == 0) || (net == (IP_LOOPBACKNET << IP_CLASSA_NSHIFT))) {
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| 185 | /* don't route loopback packets */
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| 186 | return 0;
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| 187 | }
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| 188 | }
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| 189 | return 1;
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| 190 | }
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| 191 |
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| 192 | /**
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| 193 | * Forwards an IP packet. It finds an appropriate route for the
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| 194 | * packet, decrements the TTL value of the packet, adjusts the
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| 195 | * checksum and outputs the packet on the appropriate interface.
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| 196 | *
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| 197 | * @param p the packet to forward (p->payload points to IP header)
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| 198 | * @param iphdr the IP header of the input packet
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| 199 | * @param inp the netif on which this packet was received
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| 200 | */
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| 201 | static void
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| 202 | ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
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| 203 | {
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| 204 | struct netif *netif;
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| 205 |
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| 206 | PERF_START;
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| 207 |
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| 208 | if (!ip_canforward(p)) {
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| 209 | goto return_noroute;
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| 210 | }
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| 211 |
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| 212 | /* RFC3927 2.7: do not forward link-local addresses */
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| 213 | if (ip_addr_islinklocal(¤t_iphdr_dest)) {
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| 214 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
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| 215 | ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest),
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| 216 | ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest)));
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| 217 | goto return_noroute;
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| 218 | }
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| 219 |
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| 220 | /* Find network interface where to forward this IP packet to. */
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| 221 | netif = ip_route(¤t_iphdr_dest);
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| 222 | if (netif == NULL) {
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| 223 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
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| 224 | ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest),
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| 225 | ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest)));
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| 226 | /* @todo: send ICMP_DUR_NET? */
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| 227 | goto return_noroute;
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| 228 | }
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| 229 | #if !IP_FORWARD_ALLOW_TX_ON_RX_NETIF
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| 230 | /* Do not forward packets onto the same network interface on which
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| 231 | * they arrived. */
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| 232 | if (netif == inp) {
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| 233 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
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| 234 | goto return_noroute;
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| 235 | }
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| 236 | #endif /* IP_FORWARD_ALLOW_TX_ON_RX_NETIF */
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| 237 |
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| 238 | /* decrement TTL */
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| 239 | IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
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| 240 | /* send ICMP if TTL == 0 */
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| 241 | if (IPH_TTL(iphdr) == 0) {
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| 242 | snmp_inc_ipinhdrerrors();
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| 243 | #if LWIP_ICMP
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| 244 | /* Don't send ICMP messages in response to ICMP messages */
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| 245 | if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
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| 246 | icmp_time_exceeded(p, ICMP_TE_TTL);
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| 247 | }
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| 248 | #endif /* LWIP_ICMP */
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| 249 | return;
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| 250 | }
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| 251 |
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| 252 | /* Incrementally update the IP checksum. */
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| 253 | if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffffU - 0x100)) {
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| 254 | IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1);
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| 255 | } else {
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| 256 | IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100));
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| 257 | }
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| 258 |
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| 259 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
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| 260 | ip4_addr1_16(¤t_iphdr_dest), ip4_addr2_16(¤t_iphdr_dest),
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| 261 | ip4_addr3_16(¤t_iphdr_dest), ip4_addr4_16(¤t_iphdr_dest)));
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| 262 |
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| 263 | IP_STATS_INC(ip.fw);
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| 264 | IP_STATS_INC(ip.xmit);
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| 265 | snmp_inc_ipforwdatagrams();
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| 266 |
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| 267 | PERF_STOP("ip_forward");
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| 268 | /* don't fragment if interface has mtu set to 0 [loopif] */
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| 269 | if (netif->mtu && (p->tot_len > netif->mtu)) {
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| 270 | if ((IPH_OFFSET(iphdr) & PP_NTOHS(IP_DF)) == 0) {
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| 271 | #if IP_FRAG
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| 272 | ip_frag(p, netif, ip_current_dest_addr());
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| 273 | #else /* IP_FRAG */
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| 274 | /* @todo: send ICMP Destination Unreacheable code 13 "Communication administratively prohibited"? */
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| 275 | #endif /* IP_FRAG */
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| 276 | } else {
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| 277 | /* send ICMP Destination Unreacheable code 4: "Fragmentation Needed and DF Set" */
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| 278 | icmp_dest_unreach(p, ICMP_DUR_FRAG);
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| 279 | }
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| 280 | return;
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| 281 | }
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| 282 | /* transmit pbuf on chosen interface */
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| 283 | netif->output(netif, p, ¤t_iphdr_dest);
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| 284 | return;
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| 285 | return_noroute:
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| 286 | snmp_inc_ipoutnoroutes();
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| 287 | }
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| 288 | #endif /* IP_FORWARD */
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| 289 |
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| 290 | /**
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| 291 | * This function is called by the network interface device driver when
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| 292 | * an IP packet is received. The function does the basic checks of the
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| 293 | * IP header such as packet size being at least larger than the header
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| 294 | * size etc. If the packet was not destined for us, the packet is
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| 295 | * forwarded (using ip_forward). The IP checksum is always checked.
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| 296 | *
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| 297 | * Finally, the packet is sent to the upper layer protocol input function.
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| 298 | *
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| 299 | * @param p the received IP packet (p->payload points to IP header)
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| 300 | * @param inp the netif on which this packet was received
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| 301 | * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
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| 302 | * processed, but currently always returns ERR_OK)
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| 303 | */
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| 304 | err_t
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| 305 | ip_input(struct pbuf *p, struct netif *inp)
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| 306 | {
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| 307 | struct ip_hdr *iphdr;
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| 308 | struct netif *netif;
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| 309 | u16_t iphdr_hlen;
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| 310 | u16_t iphdr_len;
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| 311 | #if IP_ACCEPT_LINK_LAYER_ADDRESSING
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| 312 | int check_ip_src=1;
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| 313 | #endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
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| 314 |
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| 315 | IP_STATS_INC(ip.recv);
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| 316 | snmp_inc_ipinreceives();
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| 317 |
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| 318 | /* identify the IP header */
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| 319 | iphdr = (struct ip_hdr *)p->payload;
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| 320 | if (IPH_V(iphdr) != 4) {
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| 321 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr)));
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| 322 | ip_debug_print(p);
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| 323 | pbuf_free(p);
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| 324 | IP_STATS_INC(ip.err);
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| 325 | IP_STATS_INC(ip.drop);
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| 326 | snmp_inc_ipinhdrerrors();
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| 327 | return ERR_OK;
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| 328 | }
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| 329 |
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| 330 | #ifdef LWIP_HOOK_IP4_INPUT
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| 331 | if (LWIP_HOOK_IP4_INPUT(p, inp)) {
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| 332 | /* the packet has been eaten */
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| 333 | return ERR_OK;
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| 334 | }
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| 335 | #endif
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| 336 |
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| 337 | /* obtain IP header length in number of 32-bit words */
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| 338 | iphdr_hlen = IPH_HL(iphdr);
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| 339 | /* calculate IP header length in bytes */
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| 340 | iphdr_hlen *= 4;
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| 341 | /* obtain ip length in bytes */
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| 342 | iphdr_len = ntohs(IPH_LEN(iphdr));
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| 343 |
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| 344 | /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
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| 345 | if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) {
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| 346 | if (iphdr_hlen > p->len) {
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| 347 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
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| 348 | ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
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| 349 | iphdr_hlen, p->len));
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| 350 | }
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| 351 | if (iphdr_len > p->tot_len) {
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| 352 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
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| 353 | ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
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| 354 | iphdr_len, p->tot_len));
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| 355 | }
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| 356 | /* free (drop) packet pbufs */
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| 357 | pbuf_free(p);
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| 358 | IP_STATS_INC(ip.lenerr);
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| 359 | IP_STATS_INC(ip.drop);
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| 360 | snmp_inc_ipindiscards();
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| 361 | return ERR_OK;
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| 362 | }
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| 363 |
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| 364 | /* verify checksum */
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| 365 | #if CHECKSUM_CHECK_IP
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| 366 | if (inet_chksum(iphdr, iphdr_hlen) != 0) {
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| 367 |
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| 368 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
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| 369 | ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen)));
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| 370 | ip_debug_print(p);
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| 371 | pbuf_free(p);
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| 372 | IP_STATS_INC(ip.chkerr);
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| 373 | IP_STATS_INC(ip.drop);
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| 374 | snmp_inc_ipinhdrerrors();
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| 375 | return ERR_OK;
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| 376 | }
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| 377 | #endif
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| 378 |
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| 379 | /* Trim pbuf. This should have been done at the netif layer,
|
---|
| 380 | * but we'll do it anyway just to be sure that its done. */
|
---|
| 381 | pbuf_realloc(p, iphdr_len);
|
---|
| 382 |
|
---|
| 383 | /* copy IP addresses to aligned ip_addr_t */
|
---|
| 384 | ip_addr_copy(current_iphdr_dest, iphdr->dest);
|
---|
| 385 | ip_addr_copy(current_iphdr_src, iphdr->src);
|
---|
| 386 |
|
---|
| 387 | /* match packet against an interface, i.e. is this packet for us? */
|
---|
| 388 | #if LWIP_IGMP
|
---|
| 389 | if (ip_addr_ismulticast(¤t_iphdr_dest)) {
|
---|
| 390 | if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, ¤t_iphdr_dest))) {
|
---|
| 391 | netif = inp;
|
---|
| 392 | } else {
|
---|
| 393 | netif = NULL;
|
---|
| 394 | }
|
---|
| 395 | } else
|
---|
| 396 | #endif /* LWIP_IGMP */
|
---|
| 397 | {
|
---|
| 398 | /* start trying with inp. if that's not acceptable, start walking the
|
---|
| 399 | list of configured netifs.
|
---|
| 400 | 'first' is used as a boolean to mark whether we started walking the list */
|
---|
| 401 | int first = 1;
|
---|
| 402 | netif = inp;
|
---|
| 403 | do {
|
---|
| 404 | 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",
|
---|
| 405 | ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr),
|
---|
| 406 | ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask),
|
---|
| 407 | ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask),
|
---|
| 408 | ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask)));
|
---|
| 409 |
|
---|
| 410 | /* interface is up and configured? */
|
---|
| 411 | if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) {
|
---|
| 412 | /* unicast to this interface address? */
|
---|
| 413 | if (ip_addr_cmp(¤t_iphdr_dest, &(netif->ip_addr)) ||
|
---|
| 414 | /* or broadcast on this interface network address? */
|
---|
| 415 | ip_addr_isbroadcast(¤t_iphdr_dest, netif)) {
|
---|
| 416 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n",
|
---|
| 417 | netif->name[0], netif->name[1]));
|
---|
| 418 | /* break out of for loop */
|
---|
| 419 | break;
|
---|
| 420 | }
|
---|
| 421 | #if LWIP_AUTOIP
|
---|
| 422 | /* connections to link-local addresses must persist after changing
|
---|
| 423 | the netif's address (RFC3927 ch. 1.9) */
|
---|
| 424 | if ((netif->autoip != NULL) &&
|
---|
| 425 | ip_addr_cmp(¤t_iphdr_dest, &(netif->autoip->llipaddr))) {
|
---|
| 426 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n",
|
---|
| 427 | netif->name[0], netif->name[1]));
|
---|
| 428 | /* break out of for loop */
|
---|
| 429 | break;
|
---|
| 430 | }
|
---|
| 431 | #endif /* LWIP_AUTOIP */
|
---|
| 432 | }
|
---|
| 433 | if (first) {
|
---|
| 434 | first = 0;
|
---|
| 435 | netif = netif_list;
|
---|
| 436 | } else {
|
---|
| 437 | netif = netif->next;
|
---|
| 438 | }
|
---|
| 439 | if (netif == inp) {
|
---|
| 440 | netif = netif->next;
|
---|
| 441 | }
|
---|
| 442 | } while(netif != NULL);
|
---|
| 443 | }
|
---|
| 444 |
|
---|
| 445 | #if IP_ACCEPT_LINK_LAYER_ADDRESSING
|
---|
| 446 | /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
|
---|
| 447 | * using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
|
---|
| 448 | * According to RFC 1542 section 3.1.1, referred by RFC 2131).
|
---|
| 449 | *
|
---|
| 450 | * If you want to accept private broadcast communication while a netif is down,
|
---|
| 451 | * define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.:
|
---|
| 452 | *
|
---|
| 453 | * #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345))
|
---|
| 454 | */
|
---|
| 455 | if (netif == NULL) {
|
---|
| 456 | /* remote port is DHCP server? */
|
---|
| 457 | if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
|
---|
| 458 | struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen);
|
---|
| 459 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
|
---|
| 460 | ntohs(udphdr->dest)));
|
---|
| 461 | if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) {
|
---|
| 462 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n"));
|
---|
| 463 | netif = inp;
|
---|
| 464 | check_ip_src = 0;
|
---|
| 465 | }
|
---|
| 466 | }
|
---|
| 467 | }
|
---|
| 468 | #endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
|
---|
| 469 |
|
---|
| 470 | /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */
|
---|
| 471 | #if IP_ACCEPT_LINK_LAYER_ADDRESSING
|
---|
| 472 | /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */
|
---|
| 473 | if (check_ip_src && !ip_addr_isany(¤t_iphdr_src))
|
---|
| 474 | #endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
|
---|
| 475 | { if ((ip_addr_isbroadcast(¤t_iphdr_src, inp)) ||
|
---|
| 476 | (ip_addr_ismulticast(¤t_iphdr_src))) {
|
---|
| 477 | /* packet source is not valid */
|
---|
| 478 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n"));
|
---|
| 479 | /* free (drop) packet pbufs */
|
---|
| 480 | pbuf_free(p);
|
---|
| 481 | IP_STATS_INC(ip.drop);
|
---|
| 482 | snmp_inc_ipinaddrerrors();
|
---|
| 483 | snmp_inc_ipindiscards();
|
---|
| 484 | return ERR_OK;
|
---|
| 485 | }
|
---|
| 486 | }
|
---|
| 487 |
|
---|
| 488 | /* packet not for us? */
|
---|
| 489 | if (netif == NULL) {
|
---|
| 490 | /* packet not for us, route or discard */
|
---|
| 491 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
|
---|
| 492 | #if IP_FORWARD
|
---|
| 493 | /* non-broadcast packet? */
|
---|
| 494 | if (!ip_addr_isbroadcast(¤t_iphdr_dest, inp)) {
|
---|
| 495 | /* try to forward IP packet on (other) interfaces */
|
---|
| 496 | ip_forward(p, iphdr, inp);
|
---|
| 497 | } else
|
---|
| 498 | #endif /* IP_FORWARD */
|
---|
| 499 | {
|
---|
| 500 | snmp_inc_ipinaddrerrors();
|
---|
| 501 | snmp_inc_ipindiscards();
|
---|
| 502 | }
|
---|
| 503 | pbuf_free(p);
|
---|
| 504 | return ERR_OK;
|
---|
| 505 | }
|
---|
| 506 | /* packet consists of multiple fragments? */
|
---|
| 507 | if ((IPH_OFFSET(iphdr) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) {
|
---|
| 508 | #if IP_REASSEMBLY /* packet fragment reassembly code present? */
|
---|
| 509 | 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",
|
---|
| 510 | 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));
|
---|
| 511 | /* reassemble the packet*/
|
---|
| 512 | p = ip_reass(p);
|
---|
| 513 | /* packet not fully reassembled yet? */
|
---|
| 514 | if (p == NULL) {
|
---|
| 515 | return ERR_OK;
|
---|
| 516 | }
|
---|
| 517 | iphdr = (struct ip_hdr *)p->payload;
|
---|
| 518 | #else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
|
---|
| 519 | pbuf_free(p);
|
---|
| 520 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
|
---|
| 521 | ntohs(IPH_OFFSET(iphdr))));
|
---|
| 522 | IP_STATS_INC(ip.opterr);
|
---|
| 523 | IP_STATS_INC(ip.drop);
|
---|
| 524 | /* unsupported protocol feature */
|
---|
| 525 | snmp_inc_ipinunknownprotos();
|
---|
| 526 | return ERR_OK;
|
---|
| 527 | #endif /* IP_REASSEMBLY */
|
---|
| 528 | }
|
---|
| 529 |
|
---|
| 530 | #if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */
|
---|
| 531 |
|
---|
| 532 | #if LWIP_IGMP
|
---|
| 533 | /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */
|
---|
| 534 | if((iphdr_hlen > IP_HLEN) && (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) {
|
---|
| 535 | #else
|
---|
| 536 | if (iphdr_hlen > IP_HLEN) {
|
---|
| 537 | #endif /* LWIP_IGMP */
|
---|
| 538 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n"));
|
---|
| 539 | pbuf_free(p);
|
---|
| 540 | IP_STATS_INC(ip.opterr);
|
---|
| 541 | IP_STATS_INC(ip.drop);
|
---|
| 542 | /* unsupported protocol feature */
|
---|
| 543 | snmp_inc_ipinunknownprotos();
|
---|
| 544 | return ERR_OK;
|
---|
| 545 | }
|
---|
| 546 | #endif /* IP_OPTIONS_ALLOWED == 0 */
|
---|
| 547 |
|
---|
| 548 | /* send to upper layers */
|
---|
| 549 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n"));
|
---|
| 550 | ip_debug_print(p);
|
---|
| 551 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
|
---|
| 552 |
|
---|
| 553 | current_netif = inp;
|
---|
| 554 | current_header = iphdr;
|
---|
| 555 |
|
---|
| 556 | #if LWIP_RAW
|
---|
| 557 | /* raw input did not eat the packet? */
|
---|
| 558 | if (raw_input(p, inp) == 0)
|
---|
| 559 | #endif /* LWIP_RAW */
|
---|
| 560 | {
|
---|
| 561 | switch (IPH_PROTO(iphdr)) {
|
---|
| 562 | #if LWIP_UDP
|
---|
| 563 | case IP_PROTO_UDP:
|
---|
| 564 | #if LWIP_UDPLITE
|
---|
| 565 | case IP_PROTO_UDPLITE:
|
---|
| 566 | #endif /* LWIP_UDPLITE */
|
---|
| 567 | snmp_inc_ipindelivers();
|
---|
| 568 | udp_input(p, inp);
|
---|
| 569 | break;
|
---|
| 570 | #endif /* LWIP_UDP */
|
---|
| 571 | #if LWIP_TCP
|
---|
| 572 | case IP_PROTO_TCP:
|
---|
| 573 | snmp_inc_ipindelivers();
|
---|
| 574 | tcp_input(p, inp);
|
---|
| 575 | break;
|
---|
| 576 | #endif /* LWIP_TCP */
|
---|
| 577 | #if LWIP_ICMP
|
---|
| 578 | case IP_PROTO_ICMP:
|
---|
| 579 | snmp_inc_ipindelivers();
|
---|
| 580 | icmp_input(p, inp);
|
---|
| 581 | break;
|
---|
| 582 | #endif /* LWIP_ICMP */
|
---|
| 583 | #if LWIP_IGMP
|
---|
| 584 | case IP_PROTO_IGMP:
|
---|
| 585 | igmp_input(p, inp, ¤t_iphdr_dest);
|
---|
| 586 | break;
|
---|
| 587 | #endif /* LWIP_IGMP */
|
---|
| 588 | default:
|
---|
| 589 | #if LWIP_ICMP
|
---|
| 590 | /* send ICMP destination protocol unreachable unless is was a broadcast */
|
---|
| 591 | if (!ip_addr_isbroadcast(¤t_iphdr_dest, inp) &&
|
---|
| 592 | !ip_addr_ismulticast(¤t_iphdr_dest)) {
|
---|
| 593 | p->payload = iphdr;
|
---|
| 594 | icmp_dest_unreach(p, ICMP_DUR_PROTO);
|
---|
| 595 | }
|
---|
| 596 | #endif /* LWIP_ICMP */
|
---|
| 597 | pbuf_free(p);
|
---|
| 598 |
|
---|
| 599 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
|
---|
| 600 |
|
---|
| 601 | IP_STATS_INC(ip.proterr);
|
---|
| 602 | IP_STATS_INC(ip.drop);
|
---|
| 603 | snmp_inc_ipinunknownprotos();
|
---|
| 604 | }
|
---|
| 605 | }
|
---|
| 606 |
|
---|
| 607 | current_netif = NULL;
|
---|
| 608 | current_header = NULL;
|
---|
| 609 | ip_addr_set_any(¤t_iphdr_src);
|
---|
| 610 | ip_addr_set_any(¤t_iphdr_dest);
|
---|
| 611 |
|
---|
| 612 | return ERR_OK;
|
---|
| 613 | }
|
---|
| 614 |
|
---|
| 615 | /**
|
---|
| 616 | * Sends an IP packet on a network interface. This function constructs
|
---|
| 617 | * the IP header and calculates the IP header checksum. If the source
|
---|
| 618 | * IP address is NULL, the IP address of the outgoing network
|
---|
| 619 | * interface is filled in as source address.
|
---|
| 620 | * If the destination IP address is IP_HDRINCL, p is assumed to already
|
---|
| 621 | * include an IP header and p->payload points to it instead of the data.
|
---|
| 622 | *
|
---|
| 623 | * @param p the packet to send (p->payload points to the data, e.g. next
|
---|
| 624 | protocol header; if dest == IP_HDRINCL, p already includes an IP
|
---|
| 625 | header and p->payload points to that IP header)
|
---|
| 626 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
|
---|
| 627 | * IP address of the netif used to send is used as source address)
|
---|
| 628 | * @param dest the destination IP address to send the packet to
|
---|
| 629 | * @param ttl the TTL value to be set in the IP header
|
---|
| 630 | * @param tos the TOS value to be set in the IP header
|
---|
| 631 | * @param proto the PROTOCOL to be set in the IP header
|
---|
| 632 | * @param netif the netif on which to send this packet
|
---|
| 633 | * @return ERR_OK if the packet was sent OK
|
---|
| 634 | * ERR_BUF if p doesn't have enough space for IP/LINK headers
|
---|
| 635 | * returns errors returned by netif->output
|
---|
| 636 | *
|
---|
| 637 | * @note ip_id: RFC791 "some host may be able to simply use
|
---|
| 638 | * unique identifiers independent of destination"
|
---|
| 639 | */
|
---|
| 640 | err_t
|
---|
| 641 | ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
|
---|
| 642 | u8_t ttl, u8_t tos,
|
---|
| 643 | u8_t proto, struct netif *netif)
|
---|
| 644 | {
|
---|
| 645 | #if IP_OPTIONS_SEND
|
---|
| 646 | return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0);
|
---|
| 647 | }
|
---|
| 648 |
|
---|
| 649 | /**
|
---|
| 650 | * Same as ip_output_if() but with the possibility to include IP options:
|
---|
| 651 | *
|
---|
| 652 | * @ param ip_options pointer to the IP options, copied into the IP header
|
---|
| 653 | * @ param optlen length of ip_options
|
---|
| 654 | */
|
---|
| 655 | err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
|
---|
| 656 | u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
|
---|
| 657 | u16_t optlen)
|
---|
| 658 | {
|
---|
| 659 | #endif /* IP_OPTIONS_SEND */
|
---|
| 660 | struct ip_hdr *iphdr;
|
---|
| 661 | ip_addr_t dest_addr;
|
---|
| 662 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 663 | u32_t chk_sum = 0;
|
---|
| 664 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 665 |
|
---|
| 666 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
|
---|
| 667 | gets altered as the packet is passed down the stack */
|
---|
| 668 | LWIP_ASSERT("p->ref == 1", p->ref == 1);
|
---|
| 669 |
|
---|
| 670 | snmp_inc_ipoutrequests();
|
---|
| 671 |
|
---|
| 672 | /* Should the IP header be generated or is it already included in p? */
|
---|
| 673 | if (dest != IP_HDRINCL) {
|
---|
| 674 | u16_t ip_hlen = IP_HLEN;
|
---|
| 675 | #if IP_OPTIONS_SEND
|
---|
| 676 | u16_t optlen_aligned = 0;
|
---|
| 677 | if (optlen != 0) {
|
---|
| 678 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 679 | int i;
|
---|
| 680 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 681 | /* round up to a multiple of 4 */
|
---|
| 682 | optlen_aligned = ((optlen + 3) & ~3);
|
---|
| 683 | ip_hlen += optlen_aligned;
|
---|
| 684 | /* First write in the IP options */
|
---|
| 685 | if (pbuf_header(p, optlen_aligned)) {
|
---|
| 686 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n"));
|
---|
| 687 | IP_STATS_INC(ip.err);
|
---|
| 688 | snmp_inc_ipoutdiscards();
|
---|
| 689 | return ERR_BUF;
|
---|
| 690 | }
|
---|
| 691 | MEMCPY(p->payload, ip_options, optlen);
|
---|
| 692 | if (optlen < optlen_aligned) {
|
---|
| 693 | /* zero the remaining bytes */
|
---|
| 694 | memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen);
|
---|
| 695 | }
|
---|
| 696 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 697 | for (i = 0; i < optlen_aligned/2; i++) {
|
---|
| 698 | chk_sum += ((u16_t*)p->payload)[i];
|
---|
| 699 | }
|
---|
| 700 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 701 | }
|
---|
| 702 | #endif /* IP_OPTIONS_SEND */
|
---|
| 703 | /* generate IP header */
|
---|
| 704 | if (pbuf_header(p, IP_HLEN)) {
|
---|
| 705 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n"));
|
---|
| 706 |
|
---|
| 707 | IP_STATS_INC(ip.err);
|
---|
| 708 | snmp_inc_ipoutdiscards();
|
---|
| 709 | return ERR_BUF;
|
---|
| 710 | }
|
---|
| 711 |
|
---|
| 712 | iphdr = (struct ip_hdr *)p->payload;
|
---|
| 713 | LWIP_ASSERT("check that first pbuf can hold struct ip_hdr",
|
---|
| 714 | (p->len >= sizeof(struct ip_hdr)));
|
---|
| 715 |
|
---|
| 716 | IPH_TTL_SET(iphdr, ttl);
|
---|
| 717 | IPH_PROTO_SET(iphdr, proto);
|
---|
| 718 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 719 | chk_sum += LWIP_MAKE_U16(proto, ttl);
|
---|
| 720 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 721 |
|
---|
| 722 | /* dest cannot be NULL here */
|
---|
| 723 | ip_addr_copy(iphdr->dest, *dest);
|
---|
| 724 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 725 | chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF;
|
---|
| 726 | chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16;
|
---|
| 727 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 728 |
|
---|
| 729 | IPH_VHL_SET(iphdr, 4, ip_hlen / 4);
|
---|
| 730 | IPH_TOS_SET(iphdr, tos);
|
---|
| 731 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 732 | chk_sum += LWIP_MAKE_U16(tos, iphdr->_v_hl);
|
---|
| 733 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 734 | IPH_LEN_SET(iphdr, htons(p->tot_len));
|
---|
| 735 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 736 | chk_sum += iphdr->_len;
|
---|
| 737 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 738 | IPH_OFFSET_SET(iphdr, 0);
|
---|
| 739 | IPH_ID_SET(iphdr, htons(ip_id));
|
---|
| 740 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 741 | chk_sum += iphdr->_id;
|
---|
| 742 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 743 | ++ip_id;
|
---|
| 744 |
|
---|
| 745 | if (ip_addr_isany(src)) {
|
---|
| 746 | ip_addr_copy(iphdr->src, netif->ip_addr);
|
---|
| 747 | } else {
|
---|
| 748 | /* src cannot be NULL here */
|
---|
| 749 | ip_addr_copy(iphdr->src, *src);
|
---|
| 750 | }
|
---|
| 751 |
|
---|
| 752 | #if CHECKSUM_GEN_IP_INLINE
|
---|
| 753 | chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF;
|
---|
| 754 | chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16;
|
---|
| 755 | chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF);
|
---|
| 756 | chk_sum = (chk_sum >> 16) + chk_sum;
|
---|
| 757 | chk_sum = ~chk_sum;
|
---|
| 758 | iphdr->_chksum = chk_sum; /* network order */
|
---|
| 759 | #else /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 760 | IPH_CHKSUM_SET(iphdr, 0);
|
---|
| 761 | #if CHECKSUM_GEN_IP
|
---|
| 762 | IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
|
---|
| 763 | #endif
|
---|
| 764 | #endif /* CHECKSUM_GEN_IP_INLINE */
|
---|
| 765 | } else {
|
---|
| 766 | /* IP header already included in p */
|
---|
| 767 | iphdr = (struct ip_hdr *)p->payload;
|
---|
| 768 | ip_addr_copy(dest_addr, iphdr->dest);
|
---|
| 769 | dest = &dest_addr;
|
---|
| 770 | }
|
---|
| 771 |
|
---|
| 772 | IP_STATS_INC(ip.xmit);
|
---|
| 773 |
|
---|
| 774 | LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
|
---|
| 775 | ip_debug_print(p);
|
---|
| 776 |
|
---|
| 777 | #if ENABLE_LOOPBACK
|
---|
| 778 | if (ip_addr_cmp(dest, &netif->ip_addr)) {
|
---|
| 779 | /* Packet to self, enqueue it for loopback */
|
---|
| 780 | LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
|
---|
| 781 | return netif_loop_output(netif, p, dest);
|
---|
| 782 | }
|
---|
| 783 | #if LWIP_IGMP
|
---|
| 784 | if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
|
---|
| 785 | netif_loop_output(netif, p, dest);
|
---|
| 786 | }
|
---|
| 787 | #endif /* LWIP_IGMP */
|
---|
| 788 | #endif /* ENABLE_LOOPBACK */
|
---|
| 789 | #if IP_FRAG
|
---|
| 790 | /* don't fragment if interface has mtu set to 0 [loopif] */
|
---|
| 791 | if (netif->mtu && (p->tot_len > netif->mtu)) {
|
---|
| 792 | return ip_frag(p, netif, dest);
|
---|
| 793 | }
|
---|
| 794 | #endif /* IP_FRAG */
|
---|
| 795 |
|
---|
| 796 | LWIP_DEBUGF(IP_DEBUG, ("netif->output()"));
|
---|
| 797 | return netif->output(netif, p, dest);
|
---|
| 798 | }
|
---|
| 799 |
|
---|
| 800 | /**
|
---|
| 801 | * Simple interface to ip_output_if. It finds the outgoing network
|
---|
| 802 | * interface and calls upon ip_output_if to do the actual work.
|
---|
| 803 | *
|
---|
| 804 | * @param p the packet to send (p->payload points to the data, e.g. next
|
---|
| 805 | protocol header; if dest == IP_HDRINCL, p already includes an IP
|
---|
| 806 | header and p->payload points to that IP header)
|
---|
| 807 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
|
---|
| 808 | * IP address of the netif used to send is used as source address)
|
---|
| 809 | * @param dest the destination IP address to send the packet to
|
---|
| 810 | * @param ttl the TTL value to be set in the IP header
|
---|
| 811 | * @param tos the TOS value to be set in the IP header
|
---|
| 812 | * @param proto the PROTOCOL to be set in the IP header
|
---|
| 813 | *
|
---|
| 814 | * @return ERR_RTE if no route is found
|
---|
| 815 | * see ip_output_if() for more return values
|
---|
| 816 | */
|
---|
| 817 | err_t
|
---|
| 818 | ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
|
---|
| 819 | u8_t ttl, u8_t tos, u8_t proto)
|
---|
| 820 | {
|
---|
| 821 | struct netif *netif;
|
---|
| 822 |
|
---|
| 823 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
|
---|
| 824 | gets altered as the packet is passed down the stack */
|
---|
| 825 | LWIP_ASSERT("p->ref == 1", p->ref == 1);
|
---|
| 826 |
|
---|
| 827 | if ((netif = ip_route(dest)) == NULL) {
|
---|
| 828 | LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
|
---|
| 829 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
|
---|
| 830 | IP_STATS_INC(ip.rterr);
|
---|
| 831 | return ERR_RTE;
|
---|
| 832 | }
|
---|
| 833 |
|
---|
| 834 | return ip_output_if(p, src, dest, ttl, tos, proto, netif);
|
---|
| 835 | }
|
---|
| 836 |
|
---|
| 837 | #if LWIP_NETIF_HWADDRHINT
|
---|
| 838 | /** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
|
---|
| 839 | * before calling ip_output_if.
|
---|
| 840 | *
|
---|
| 841 | * @param p the packet to send (p->payload points to the data, e.g. next
|
---|
| 842 | protocol header; if dest == IP_HDRINCL, p already includes an IP
|
---|
| 843 | header and p->payload points to that IP header)
|
---|
| 844 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the
|
---|
| 845 | * IP address of the netif used to send is used as source address)
|
---|
| 846 | * @param dest the destination IP address to send the packet to
|
---|
| 847 | * @param ttl the TTL value to be set in the IP header
|
---|
| 848 | * @param tos the TOS value to be set in the IP header
|
---|
| 849 | * @param proto the PROTOCOL to be set in the IP header
|
---|
| 850 | * @param addr_hint address hint pointer set to netif->addr_hint before
|
---|
| 851 | * calling ip_output_if()
|
---|
| 852 | *
|
---|
| 853 | * @return ERR_RTE if no route is found
|
---|
| 854 | * see ip_output_if() for more return values
|
---|
| 855 | */
|
---|
| 856 | err_t
|
---|
| 857 | ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
|
---|
| 858 | u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
|
---|
| 859 | {
|
---|
| 860 | struct netif *netif;
|
---|
| 861 | err_t err;
|
---|
| 862 |
|
---|
| 863 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer
|
---|
| 864 | gets altered as the packet is passed down the stack */
|
---|
| 865 | LWIP_ASSERT("p->ref == 1", p->ref == 1);
|
---|
| 866 |
|
---|
| 867 | if ((netif = ip_route(dest)) == NULL) {
|
---|
| 868 | LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
|
---|
| 869 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
|
---|
| 870 | IP_STATS_INC(ip.rterr);
|
---|
| 871 | return ERR_RTE;
|
---|
| 872 | }
|
---|
| 873 |
|
---|
| 874 | NETIF_SET_HWADDRHINT(netif, addr_hint);
|
---|
| 875 | err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
|
---|
| 876 | NETIF_SET_HWADDRHINT(netif, NULL);
|
---|
| 877 |
|
---|
| 878 | return err;
|
---|
| 879 | }
|
---|
| 880 | #endif /* LWIP_NETIF_HWADDRHINT*/
|
---|
| 881 |
|
---|
| 882 | #if IP_DEBUG
|
---|
| 883 | /* Print an IP header by using LWIP_DEBUGF
|
---|
| 884 | * @param p an IP packet, p->payload pointing to the IP header
|
---|
| 885 | */
|
---|
| 886 | void
|
---|
| 887 | ip_debug_print(struct pbuf *p)
|
---|
| 888 | {
|
---|
| 889 | struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
|
---|
| 890 |
|
---|
| 891 | LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
|
---|
| 892 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 893 | LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n",
|
---|
| 894 | IPH_V(iphdr),
|
---|
| 895 | IPH_HL(iphdr),
|
---|
| 896 | IPH_TOS(iphdr),
|
---|
| 897 | ntohs(IPH_LEN(iphdr))));
|
---|
| 898 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 899 | LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" |%"U16_F"%"U16_F"%"U16_F"| %4"U16_F" | (id, flags, offset)\n",
|
---|
| 900 | ntohs(IPH_ID(iphdr)),
|
---|
| 901 | ntohs(IPH_OFFSET(iphdr)) >> 15 & 1,
|
---|
| 902 | ntohs(IPH_OFFSET(iphdr)) >> 14 & 1,
|
---|
| 903 | ntohs(IPH_OFFSET(iphdr)) >> 13 & 1,
|
---|
| 904 | ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK));
|
---|
| 905 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 906 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | 0x%04"X16_F" | (ttl, proto, chksum)\n",
|
---|
| 907 | IPH_TTL(iphdr),
|
---|
| 908 | IPH_PROTO(iphdr),
|
---|
| 909 | ntohs(IPH_CHKSUM(iphdr))));
|
---|
| 910 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 911 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (src)\n",
|
---|
| 912 | ip4_addr1_16(&iphdr->src),
|
---|
| 913 | ip4_addr2_16(&iphdr->src),
|
---|
| 914 | ip4_addr3_16(&iphdr->src),
|
---|
| 915 | ip4_addr4_16(&iphdr->src)));
|
---|
| 916 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 917 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n",
|
---|
| 918 | ip4_addr1_16(&iphdr->dest),
|
---|
| 919 | ip4_addr2_16(&iphdr->dest),
|
---|
| 920 | ip4_addr3_16(&iphdr->dest),
|
---|
| 921 | ip4_addr4_16(&iphdr->dest)));
|
---|
| 922 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
|
---|
| 923 | }
|
---|
| 924 | #endif /* IP_DEBUG */
|
---|