Donatien Garnier
ZG2100 Network interface source
lwip/core/ipv4/ip.c@0:b802fc31f1db, 2010-07-09 (annotated)
- Committer:
- donatien
- Date:
- Fri Jul 09 15:37:23 2010 +0000
- Revision:
- 0:b802fc31f1db
- Child:
- 1:3a7c15057192
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| donatien | 0:b802fc31f1db | 1 | /** |
| donatien | 0:b802fc31f1db | 2 | * @file |
| donatien | 0:b802fc31f1db | 3 | * This is the IPv4 layer implementation for incoming and outgoing IP traffic. |
| donatien | 0:b802fc31f1db | 4 | * |
| donatien | 0:b802fc31f1db | 5 | * @see ip_frag.c |
| donatien | 0:b802fc31f1db | 6 | * |
| donatien | 0:b802fc31f1db | 7 | */ |
| donatien | 0:b802fc31f1db | 8 | |
| donatien | 0:b802fc31f1db | 9 | /* |
| donatien | 0:b802fc31f1db | 10 | * Copyright (c) 2001-2004 Swedish Institute of Computer Science. |
| donatien | 0:b802fc31f1db | 11 | * All rights reserved. |
| donatien | 0:b802fc31f1db | 12 | * |
| donatien | 0:b802fc31f1db | 13 | * Redistribution and use in source and binary forms, with or without modification, |
| donatien | 0:b802fc31f1db | 14 | * are permitted provided that the following conditions are met: |
| donatien | 0:b802fc31f1db | 15 | * |
| donatien | 0:b802fc31f1db | 16 | * 1. Redistributions of source code must retain the above copyright notice, |
| donatien | 0:b802fc31f1db | 17 | * this list of conditions and the following disclaimer. |
| donatien | 0:b802fc31f1db | 18 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| donatien | 0:b802fc31f1db | 19 | * this list of conditions and the following disclaimer in the documentation |
| donatien | 0:b802fc31f1db | 20 | * and/or other materials provided with the distribution. |
| donatien | 0:b802fc31f1db | 21 | * 3. The name of the author may not be used to endorse or promote products |
| donatien | 0:b802fc31f1db | 22 | * derived from this software without specific prior written permission. |
| donatien | 0:b802fc31f1db | 23 | * |
| donatien | 0:b802fc31f1db | 24 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| donatien | 0:b802fc31f1db | 25 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| donatien | 0:b802fc31f1db | 26 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| donatien | 0:b802fc31f1db | 27 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| donatien | 0:b802fc31f1db | 28 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| donatien | 0:b802fc31f1db | 29 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| donatien | 0:b802fc31f1db | 30 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| donatien | 0:b802fc31f1db | 31 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| donatien | 0:b802fc31f1db | 32 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| donatien | 0:b802fc31f1db | 33 | * OF SUCH DAMAGE. |
| donatien | 0:b802fc31f1db | 34 | * |
| donatien | 0:b802fc31f1db | 35 | * This file is part of the lwIP TCP/IP stack. |
| donatien | 0:b802fc31f1db | 36 | * |
| donatien | 0:b802fc31f1db | 37 | * Author: Adam Dunkels <adam@sics.se> |
| donatien | 0:b802fc31f1db | 38 | * |
| donatien | 0:b802fc31f1db | 39 | */ |
| donatien | 0:b802fc31f1db | 40 | |
| donatien | 0:b802fc31f1db | 41 | #include "lwip/opt.h" |
| donatien | 0:b802fc31f1db | 42 | #include "lwip/ip.h" |
| donatien | 0:b802fc31f1db | 43 | #include "lwip/def.h" |
| donatien | 0:b802fc31f1db | 44 | #include "lwip/mem.h" |
| donatien | 0:b802fc31f1db | 45 | #include "lwip/ip_frag.h" |
| donatien | 0:b802fc31f1db | 46 | #include "lwip/inet_chksum.h" |
| donatien | 0:b802fc31f1db | 47 | #include "lwip/netif.h" |
| donatien | 0:b802fc31f1db | 48 | #include "lwip/icmp.h" |
| donatien | 0:b802fc31f1db | 49 | #include "lwip/igmp.h" |
| donatien | 0:b802fc31f1db | 50 | #include "lwip/raw.h" |
| donatien | 0:b802fc31f1db | 51 | #include "lwip/udp.h" |
| donatien | 0:b802fc31f1db | 52 | #include "lwip/tcp_impl.h" |
| donatien | 0:b802fc31f1db | 53 | #include "lwip/snmp.h" |
| donatien | 0:b802fc31f1db | 54 | #include "lwip/dhcp.h" |
| donatien | 0:b802fc31f1db | 55 | #include "lwip/autoip.h" |
| donatien | 0:b802fc31f1db | 56 | #include "lwip/stats.h" |
| donatien | 0:b802fc31f1db | 57 | #include "arch/perf.h" |
| donatien | 0:b802fc31f1db | 58 | |
| donatien | 0:b802fc31f1db | 59 | #include <string.h> |
| donatien | 0:b802fc31f1db | 60 | |
| donatien | 0:b802fc31f1db | 61 | /** |
| donatien | 0:b802fc31f1db | 62 | * The interface that provided the packet for the current callback |
| donatien | 0:b802fc31f1db | 63 | * invocation. |
| donatien | 0:b802fc31f1db | 64 | */ |
| donatien | 0:b802fc31f1db | 65 | struct netif *current_netif; |
| donatien | 0:b802fc31f1db | 66 | |
| donatien | 0:b802fc31f1db | 67 | /** |
| donatien | 0:b802fc31f1db | 68 | * Header of the input packet currently being processed. |
| donatien | 0:b802fc31f1db | 69 | */ |
| donatien | 0:b802fc31f1db | 70 | const struct ip_hdr *current_header; |
| donatien | 0:b802fc31f1db | 71 | |
| donatien | 0:b802fc31f1db | 72 | /** |
| donatien | 0:b802fc31f1db | 73 | * Finds the appropriate network interface for a given IP address. It |
| donatien | 0:b802fc31f1db | 74 | * searches the list of network interfaces linearly. A match is found |
| donatien | 0:b802fc31f1db | 75 | * if the masked IP address of the network interface equals the masked |
| donatien | 0:b802fc31f1db | 76 | * IP address given to the function. |
| donatien | 0:b802fc31f1db | 77 | * |
| donatien | 0:b802fc31f1db | 78 | * @param dest the destination IP address for which to find the route |
| donatien | 0:b802fc31f1db | 79 | * @return the netif on which to send to reach dest |
| donatien | 0:b802fc31f1db | 80 | */ |
| donatien | 0:b802fc31f1db | 81 | struct netif * |
| donatien | 0:b802fc31f1db | 82 | ip_route(ip_addr_t *dest) |
| donatien | 0:b802fc31f1db | 83 | { |
| donatien | 0:b802fc31f1db | 84 | struct netif *netif; |
| donatien | 0:b802fc31f1db | 85 | |
| donatien | 0:b802fc31f1db | 86 | /* iterate through netifs */ |
| donatien | 0:b802fc31f1db | 87 | for(netif = netif_list; netif != NULL; netif = netif->next) { |
| donatien | 0:b802fc31f1db | 88 | /* network mask matches? */ |
| donatien | 0:b802fc31f1db | 89 | if (netif_is_up(netif)) { |
| donatien | 0:b802fc31f1db | 90 | if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) { |
| donatien | 0:b802fc31f1db | 91 | /* return netif on which to forward IP packet */ |
| donatien | 0:b802fc31f1db | 92 | return netif; |
| donatien | 0:b802fc31f1db | 93 | } |
| donatien | 0:b802fc31f1db | 94 | } |
| donatien | 0:b802fc31f1db | 95 | } |
| donatien | 0:b802fc31f1db | 96 | if ((netif_default == NULL) || (!netif_is_up(netif_default))) { |
| donatien | 0:b802fc31f1db | 97 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", |
| donatien | 0:b802fc31f1db | 98 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); |
| donatien | 0:b802fc31f1db | 99 | IP_STATS_INC(ip.rterr); |
| donatien | 0:b802fc31f1db | 100 | snmp_inc_ipoutnoroutes(); |
| donatien | 0:b802fc31f1db | 101 | return NULL; |
| donatien | 0:b802fc31f1db | 102 | } |
| donatien | 0:b802fc31f1db | 103 | /* no matching netif found, use default netif */ |
| donatien | 0:b802fc31f1db | 104 | return netif_default; |
| donatien | 0:b802fc31f1db | 105 | } |
| donatien | 0:b802fc31f1db | 106 | |
| donatien | 0:b802fc31f1db | 107 | #if IP_FORWARD |
| donatien | 0:b802fc31f1db | 108 | /** |
| donatien | 0:b802fc31f1db | 109 | * Forwards an IP packet. It finds an appropriate route for the |
| donatien | 0:b802fc31f1db | 110 | * packet, decrements the TTL value of the packet, adjusts the |
| donatien | 0:b802fc31f1db | 111 | * checksum and outputs the packet on the appropriate interface. |
| donatien | 0:b802fc31f1db | 112 | * |
| donatien | 0:b802fc31f1db | 113 | * @param p the packet to forward (p->payload points to IP header) |
| donatien | 0:b802fc31f1db | 114 | * @param iphdr the IP header of the input packet |
| donatien | 0:b802fc31f1db | 115 | * @param inp the netif on which this packet was received |
| donatien | 0:b802fc31f1db | 116 | * @return the netif on which the packet was sent (NULL if it wasn't sent) |
| donatien | 0:b802fc31f1db | 117 | */ |
| donatien | 0:b802fc31f1db | 118 | static struct netif * |
| donatien | 0:b802fc31f1db | 119 | ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp) |
| donatien | 0:b802fc31f1db | 120 | { |
| donatien | 0:b802fc31f1db | 121 | struct netif *netif; |
| donatien | 0:b802fc31f1db | 122 | ip_addr_t dest; |
| donatien | 0:b802fc31f1db | 123 | |
| donatien | 0:b802fc31f1db | 124 | PERF_START; |
| donatien | 0:b802fc31f1db | 125 | dest = iphdr->dest; |
| donatien | 0:b802fc31f1db | 126 | |
| donatien | 0:b802fc31f1db | 127 | /* RFC3927 2.7: do not forward link-local addresses */ |
| donatien | 0:b802fc31f1db | 128 | if (ip_addr_islinklocal(&dest)) { |
| donatien | 0:b802fc31f1db | 129 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", |
| donatien | 0:b802fc31f1db | 130 | ip4_addr1_16(&dest), ip4_addr2_16(&dest), ip4_addr3_16(&dest), ip4_addr4_16(&dest))); |
| donatien | 0:b802fc31f1db | 131 | snmp_inc_ipoutnoroutes(); |
| donatien | 0:b802fc31f1db | 132 | return (struct netif *)NULL; |
| donatien | 0:b802fc31f1db | 133 | } |
| donatien | 0:b802fc31f1db | 134 | |
| donatien | 0:b802fc31f1db | 135 | /* Find network interface where to forward this IP packet to. */ |
| donatien | 0:b802fc31f1db | 136 | netif = ip_route(&dest); |
| donatien | 0:b802fc31f1db | 137 | if (netif == NULL) { |
| donatien | 0:b802fc31f1db | 138 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n", |
| donatien | 0:b802fc31f1db | 139 | ip4_addr1_16(&dest), ip4_addr2_16(&dest), ip4_addr3_16(&dest), ip4_addr4_16(&dest))); |
| donatien | 0:b802fc31f1db | 140 | snmp_inc_ipoutnoroutes(); |
| donatien | 0:b802fc31f1db | 141 | return (struct netif *)NULL; |
| donatien | 0:b802fc31f1db | 142 | } |
| donatien | 0:b802fc31f1db | 143 | /* Do not forward packets onto the same network interface on which |
| donatien | 0:b802fc31f1db | 144 | * they arrived. */ |
| donatien | 0:b802fc31f1db | 145 | if (netif == inp) { |
| donatien | 0:b802fc31f1db | 146 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n")); |
| donatien | 0:b802fc31f1db | 147 | snmp_inc_ipoutnoroutes(); |
| donatien | 0:b802fc31f1db | 148 | return (struct netif *)NULL; |
| donatien | 0:b802fc31f1db | 149 | } |
| donatien | 0:b802fc31f1db | 150 | |
| donatien | 0:b802fc31f1db | 151 | /* decrement TTL */ |
| donatien | 0:b802fc31f1db | 152 | IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1); |
| donatien | 0:b802fc31f1db | 153 | /* send ICMP if TTL == 0 */ |
| donatien | 0:b802fc31f1db | 154 | if (IPH_TTL(iphdr) == 0) { |
| donatien | 0:b802fc31f1db | 155 | snmp_inc_ipinhdrerrors(); |
| donatien | 0:b802fc31f1db | 156 | #if LWIP_ICMP |
| donatien | 0:b802fc31f1db | 157 | /* Don't send ICMP messages in response to ICMP messages */ |
| donatien | 0:b802fc31f1db | 158 | if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) { |
| donatien | 0:b802fc31f1db | 159 | icmp_time_exceeded(p, ICMP_TE_TTL); |
| donatien | 0:b802fc31f1db | 160 | } |
| donatien | 0:b802fc31f1db | 161 | #endif /* LWIP_ICMP */ |
| donatien | 0:b802fc31f1db | 162 | return (struct netif *)NULL; |
| donatien | 0:b802fc31f1db | 163 | } |
| donatien | 0:b802fc31f1db | 164 | |
| donatien | 0:b802fc31f1db | 165 | /* Incrementally update the IP checksum. */ |
| donatien | 0:b802fc31f1db | 166 | if (IPH_CHKSUM(iphdr) >= htons(0xffff - 0x100)) { |
| donatien | 0:b802fc31f1db | 167 | IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + htons(0x100) + 1); |
| donatien | 0:b802fc31f1db | 168 | } else { |
| donatien | 0:b802fc31f1db | 169 | IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + htons(0x100)); |
| donatien | 0:b802fc31f1db | 170 | } |
| donatien | 0:b802fc31f1db | 171 | |
| donatien | 0:b802fc31f1db | 172 | LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", |
| donatien | 0:b802fc31f1db | 173 | ip4_addr1_16(&dest), ip4_addr2_16(&dest), ip4_addr3_16(&dest), ip4_addr4_16(&dest))); |
| donatien | 0:b802fc31f1db | 174 | |
| donatien | 0:b802fc31f1db | 175 | IP_STATS_INC(ip.fw); |
| donatien | 0:b802fc31f1db | 176 | IP_STATS_INC(ip.xmit); |
| donatien | 0:b802fc31f1db | 177 | snmp_inc_ipforwdatagrams(); |
| donatien | 0:b802fc31f1db | 178 | |
| donatien | 0:b802fc31f1db | 179 | PERF_STOP("ip_forward"); |
| donatien | 0:b802fc31f1db | 180 | /* transmit pbuf on chosen interface */ |
| donatien | 0:b802fc31f1db | 181 | netif->output(netif, p, &dest); |
| donatien | 0:b802fc31f1db | 182 | return netif; |
| donatien | 0:b802fc31f1db | 183 | } |
| donatien | 0:b802fc31f1db | 184 | #endif /* IP_FORWARD */ |
| donatien | 0:b802fc31f1db | 185 | |
| donatien | 0:b802fc31f1db | 186 | /** |
| donatien | 0:b802fc31f1db | 187 | * This function is called by the network interface device driver when |
| donatien | 0:b802fc31f1db | 188 | * an IP packet is received. The function does the basic checks of the |
| donatien | 0:b802fc31f1db | 189 | * IP header such as packet size being at least larger than the header |
| donatien | 0:b802fc31f1db | 190 | * size etc. If the packet was not destined for us, the packet is |
| donatien | 0:b802fc31f1db | 191 | * forwarded (using ip_forward). The IP checksum is always checked. |
| donatien | 0:b802fc31f1db | 192 | * |
| donatien | 0:b802fc31f1db | 193 | * Finally, the packet is sent to the upper layer protocol input function. |
| donatien | 0:b802fc31f1db | 194 | * |
| donatien | 0:b802fc31f1db | 195 | * @param p the received IP packet (p->payload points to IP header) |
| donatien | 0:b802fc31f1db | 196 | * @param inp the netif on which this packet was received |
| donatien | 0:b802fc31f1db | 197 | * @return ERR_OK if the packet was processed (could return ERR_* if it wasn't |
| donatien | 0:b802fc31f1db | 198 | * processed, but currently always returns ERR_OK) |
| donatien | 0:b802fc31f1db | 199 | */ |
| donatien | 0:b802fc31f1db | 200 | err_t |
| donatien | 0:b802fc31f1db | 201 | ip_input(struct pbuf *p, struct netif *inp) |
| donatien | 0:b802fc31f1db | 202 | { |
| donatien | 0:b802fc31f1db | 203 | struct ip_hdr *iphdr; |
| donatien | 0:b802fc31f1db | 204 | struct netif *netif; |
| donatien | 0:b802fc31f1db | 205 | u16_t iphdr_hlen; |
| donatien | 0:b802fc31f1db | 206 | u16_t iphdr_len; |
| donatien | 0:b802fc31f1db | 207 | #if LWIP_DHCP |
| donatien | 0:b802fc31f1db | 208 | int check_ip_src=1; |
| donatien | 0:b802fc31f1db | 209 | #endif /* LWIP_DHCP */ |
| donatien | 0:b802fc31f1db | 210 | |
| donatien | 0:b802fc31f1db | 211 | IP_STATS_INC(ip.recv); |
| donatien | 0:b802fc31f1db | 212 | snmp_inc_ipinreceives(); |
| donatien | 0:b802fc31f1db | 213 | |
| donatien | 0:b802fc31f1db | 214 | /* identify the IP header */ |
| donatien | 0:b802fc31f1db | 215 | iphdr = (struct ip_hdr *)p->payload; |
| donatien | 0:b802fc31f1db | 216 | if (IPH_V(iphdr) != 4) { |
| donatien | 0:b802fc31f1db | 217 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr))); |
| donatien | 0:b802fc31f1db | 218 | ip_debug_print(p); |
| donatien | 0:b802fc31f1db | 219 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 220 | IP_STATS_INC(ip.err); |
| donatien | 0:b802fc31f1db | 221 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 222 | snmp_inc_ipinhdrerrors(); |
| donatien | 0:b802fc31f1db | 223 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 224 | } |
| donatien | 0:b802fc31f1db | 225 | |
| donatien | 0:b802fc31f1db | 226 | /* obtain IP header length in number of 32-bit words */ |
| donatien | 0:b802fc31f1db | 227 | iphdr_hlen = IPH_HL(iphdr); |
| donatien | 0:b802fc31f1db | 228 | /* calculate IP header length in bytes */ |
| donatien | 0:b802fc31f1db | 229 | iphdr_hlen *= 4; |
| donatien | 0:b802fc31f1db | 230 | /* obtain ip length in bytes */ |
| donatien | 0:b802fc31f1db | 231 | iphdr_len = ntohs(IPH_LEN(iphdr)); |
| donatien | 0:b802fc31f1db | 232 | |
| donatien | 0:b802fc31f1db | 233 | /* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */ |
| donatien | 0:b802fc31f1db | 234 | if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) { |
| donatien | 0:b802fc31f1db | 235 | if (iphdr_hlen > p->len) { |
| donatien | 0:b802fc31f1db | 236 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, |
| donatien | 0:b802fc31f1db | 237 | ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n", |
| donatien | 0:b802fc31f1db | 238 | iphdr_hlen, p->len)); |
| donatien | 0:b802fc31f1db | 239 | } |
| donatien | 0:b802fc31f1db | 240 | if (iphdr_len > p->tot_len) { |
| donatien | 0:b802fc31f1db | 241 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, |
| donatien | 0:b802fc31f1db | 242 | ("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n", |
| donatien | 0:b802fc31f1db | 243 | iphdr_len, p->tot_len)); |
| donatien | 0:b802fc31f1db | 244 | } |
| donatien | 0:b802fc31f1db | 245 | /* free (drop) packet pbufs */ |
| donatien | 0:b802fc31f1db | 246 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 247 | IP_STATS_INC(ip.lenerr); |
| donatien | 0:b802fc31f1db | 248 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 249 | snmp_inc_ipindiscards(); |
| donatien | 0:b802fc31f1db | 250 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 251 | } |
| donatien | 0:b802fc31f1db | 252 | |
| donatien | 0:b802fc31f1db | 253 | /* verify checksum */ |
| donatien | 0:b802fc31f1db | 254 | #if CHECKSUM_CHECK_IP |
| donatien | 0:b802fc31f1db | 255 | if (inet_chksum(iphdr, iphdr_hlen) != 0) { |
| donatien | 0:b802fc31f1db | 256 | |
| donatien | 0:b802fc31f1db | 257 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, |
| donatien | 0:b802fc31f1db | 258 | ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen))); |
| donatien | 0:b802fc31f1db | 259 | ip_debug_print(p); |
| donatien | 0:b802fc31f1db | 260 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 261 | IP_STATS_INC(ip.chkerr); |
| donatien | 0:b802fc31f1db | 262 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 263 | snmp_inc_ipinhdrerrors(); |
| donatien | 0:b802fc31f1db | 264 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 265 | } |
| donatien | 0:b802fc31f1db | 266 | #endif |
| donatien | 0:b802fc31f1db | 267 | |
| donatien | 0:b802fc31f1db | 268 | /* Trim pbuf. This should have been done at the netif layer, |
| donatien | 0:b802fc31f1db | 269 | * but we'll do it anyway just to be sure that its done. */ |
| donatien | 0:b802fc31f1db | 270 | pbuf_realloc(p, iphdr_len); |
| donatien | 0:b802fc31f1db | 271 | |
| donatien | 0:b802fc31f1db | 272 | /* match packet against an interface, i.e. is this packet for us? */ |
| donatien | 0:b802fc31f1db | 273 | #if LWIP_IGMP |
| donatien | 0:b802fc31f1db | 274 | if (ip_addr_ismulticast(&(iphdr->dest))) { |
| donatien | 0:b802fc31f1db | 275 | if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, &(iphdr->dest)))) { |
| donatien | 0:b802fc31f1db | 276 | netif = inp; |
| donatien | 0:b802fc31f1db | 277 | } else { |
| donatien | 0:b802fc31f1db | 278 | netif = NULL; |
| donatien | 0:b802fc31f1db | 279 | } |
| donatien | 0:b802fc31f1db | 280 | } else |
| donatien | 0:b802fc31f1db | 281 | #endif /* LWIP_IGMP */ |
| donatien | 0:b802fc31f1db | 282 | { |
| donatien | 0:b802fc31f1db | 283 | /* start trying with inp. if that's not acceptable, start walking the |
| donatien | 0:b802fc31f1db | 284 | list of configured netifs. |
| donatien | 0:b802fc31f1db | 285 | 'first' is used as a boolean to mark whether we started walking the list */ |
| donatien | 0:b802fc31f1db | 286 | int first = 1; |
| donatien | 0:b802fc31f1db | 287 | netif = inp; |
| donatien | 0:b802fc31f1db | 288 | do { |
| donatien | 0:b802fc31f1db | 289 | 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", |
| donatien | 0:b802fc31f1db | 290 | ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr), |
| donatien | 0:b802fc31f1db | 291 | ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask), |
| donatien | 0:b802fc31f1db | 292 | ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask), |
| donatien | 0:b802fc31f1db | 293 | ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask))); |
| donatien | 0:b802fc31f1db | 294 | |
| donatien | 0:b802fc31f1db | 295 | /* interface is up and configured? */ |
| donatien | 0:b802fc31f1db | 296 | if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr)))) { |
| donatien | 0:b802fc31f1db | 297 | /* unicast to this interface address? */ |
| donatien | 0:b802fc31f1db | 298 | if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr)) || |
| donatien | 0:b802fc31f1db | 299 | /* or broadcast on this interface network address? */ |
| donatien | 0:b802fc31f1db | 300 | ip_addr_isbroadcast(&(iphdr->dest), netif)) { |
| donatien | 0:b802fc31f1db | 301 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n", |
| donatien | 0:b802fc31f1db | 302 | netif->name[0], netif->name[1])); |
| donatien | 0:b802fc31f1db | 303 | /* break out of for loop */ |
| donatien | 0:b802fc31f1db | 304 | break; |
| donatien | 0:b802fc31f1db | 305 | } |
| donatien | 0:b802fc31f1db | 306 | #if LWIP_AUTOIP |
| donatien | 0:b802fc31f1db | 307 | /* connections to link-local addresses must persist after changing |
| donatien | 0:b802fc31f1db | 308 | the netif's address (RFC3927 ch. 1.9) */ |
| donatien | 0:b802fc31f1db | 309 | if ((netif->autoip != NULL) && |
| donatien | 0:b802fc31f1db | 310 | ip_addr_cmp(&(iphdr->dest), &(netif->autoip->llipaddr))) { |
| donatien | 0:b802fc31f1db | 311 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n", |
| donatien | 0:b802fc31f1db | 312 | netif->name[0], netif->name[1])); |
| donatien | 0:b802fc31f1db | 313 | /* break out of for loop */ |
| donatien | 0:b802fc31f1db | 314 | break; |
| donatien | 0:b802fc31f1db | 315 | } |
| donatien | 0:b802fc31f1db | 316 | #endif /* LWIP_AUTOIP */ |
| donatien | 0:b802fc31f1db | 317 | } |
| donatien | 0:b802fc31f1db | 318 | if (first) { |
| donatien | 0:b802fc31f1db | 319 | first = 0; |
| donatien | 0:b802fc31f1db | 320 | netif = netif_list; |
| donatien | 0:b802fc31f1db | 321 | } else { |
| donatien | 0:b802fc31f1db | 322 | netif = netif->next; |
| donatien | 0:b802fc31f1db | 323 | } |
| donatien | 0:b802fc31f1db | 324 | if (netif == inp) { |
| donatien | 0:b802fc31f1db | 325 | netif = netif->next; |
| donatien | 0:b802fc31f1db | 326 | } |
| donatien | 0:b802fc31f1db | 327 | } while(netif != NULL); |
| donatien | 0:b802fc31f1db | 328 | } |
| donatien | 0:b802fc31f1db | 329 | |
| donatien | 0:b802fc31f1db | 330 | #if LWIP_DHCP |
| donatien | 0:b802fc31f1db | 331 | /* Pass DHCP messages regardless of destination address. DHCP traffic is addressed |
| donatien | 0:b802fc31f1db | 332 | * using link layer addressing (such as Ethernet MAC) so we must not filter on IP. |
| donatien | 0:b802fc31f1db | 333 | * According to RFC 1542 section 3.1.1, referred by RFC 2131). |
| donatien | 0:b802fc31f1db | 334 | */ |
| donatien | 0:b802fc31f1db | 335 | if (netif == NULL) { |
| donatien | 0:b802fc31f1db | 336 | /* remote port is DHCP server? */ |
| donatien | 0:b802fc31f1db | 337 | if (IPH_PROTO(iphdr) == IP_PROTO_UDP) { |
| donatien | 0:b802fc31f1db | 338 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n", |
| donatien | 0:b802fc31f1db | 339 | ntohs(((struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen))->dest))); |
| donatien | 0:b802fc31f1db | 340 | if (ntohs(((struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen))->dest) == DHCP_CLIENT_PORT) { |
| donatien | 0:b802fc31f1db | 341 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n")); |
| donatien | 0:b802fc31f1db | 342 | netif = inp; |
| donatien | 0:b802fc31f1db | 343 | check_ip_src = 0; |
| donatien | 0:b802fc31f1db | 344 | } |
| donatien | 0:b802fc31f1db | 345 | } |
| donatien | 0:b802fc31f1db | 346 | } |
| donatien | 0:b802fc31f1db | 347 | #endif /* LWIP_DHCP */ |
| donatien | 0:b802fc31f1db | 348 | |
| donatien | 0:b802fc31f1db | 349 | /* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */ |
| donatien | 0:b802fc31f1db | 350 | #if LWIP_DHCP |
| donatien | 0:b802fc31f1db | 351 | /* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */ |
| donatien | 0:b802fc31f1db | 352 | if (check_ip_src && !ip_addr_isany(&iphdr->src)) |
| donatien | 0:b802fc31f1db | 353 | #endif /* LWIP_DHCP */ |
| donatien | 0:b802fc31f1db | 354 | { if ((ip_addr_isbroadcast(&(iphdr->src), inp)) || |
| donatien | 0:b802fc31f1db | 355 | (ip_addr_ismulticast(&(iphdr->src)))) { |
| donatien | 0:b802fc31f1db | 356 | /* packet source is not valid */ |
| donatien | 0:b802fc31f1db | 357 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n")); |
| donatien | 0:b802fc31f1db | 358 | /* free (drop) packet pbufs */ |
| donatien | 0:b802fc31f1db | 359 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 360 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 361 | snmp_inc_ipinaddrerrors(); |
| donatien | 0:b802fc31f1db | 362 | snmp_inc_ipindiscards(); |
| donatien | 0:b802fc31f1db | 363 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 364 | } |
| donatien | 0:b802fc31f1db | 365 | } |
| donatien | 0:b802fc31f1db | 366 | |
| donatien | 0:b802fc31f1db | 367 | /* packet not for us? */ |
| donatien | 0:b802fc31f1db | 368 | if (netif == NULL) { |
| donatien | 0:b802fc31f1db | 369 | /* packet not for us, route or discard */ |
| donatien | 0:b802fc31f1db | 370 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n")); |
| donatien | 0:b802fc31f1db | 371 | #if IP_FORWARD |
| donatien | 0:b802fc31f1db | 372 | /* non-broadcast packet? */ |
| donatien | 0:b802fc31f1db | 373 | if (!ip_addr_isbroadcast(&(iphdr->dest), inp)) { |
| donatien | 0:b802fc31f1db | 374 | /* try to forward IP packet on (other) interfaces */ |
| donatien | 0:b802fc31f1db | 375 | ip_forward(p, iphdr, inp); |
| donatien | 0:b802fc31f1db | 376 | } else |
| donatien | 0:b802fc31f1db | 377 | #endif /* IP_FORWARD */ |
| donatien | 0:b802fc31f1db | 378 | { |
| donatien | 0:b802fc31f1db | 379 | snmp_inc_ipinaddrerrors(); |
| donatien | 0:b802fc31f1db | 380 | snmp_inc_ipindiscards(); |
| donatien | 0:b802fc31f1db | 381 | } |
| donatien | 0:b802fc31f1db | 382 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 383 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 384 | } |
| donatien | 0:b802fc31f1db | 385 | /* packet consists of multiple fragments? */ |
| donatien | 0:b802fc31f1db | 386 | if ((IPH_OFFSET(iphdr) & htons(IP_OFFMASK | IP_MF)) != 0) { |
| donatien | 0:b802fc31f1db | 387 | #if IP_REASSEMBLY /* packet fragment reassembly code present? */ |
| donatien | 0:b802fc31f1db | 388 | 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", |
| donatien | 0:b802fc31f1db | 389 | ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & htons(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8)); |
| donatien | 0:b802fc31f1db | 390 | /* reassemble the packet*/ |
| donatien | 0:b802fc31f1db | 391 | p = ip_reass(p); |
| donatien | 0:b802fc31f1db | 392 | /* packet not fully reassembled yet? */ |
| donatien | 0:b802fc31f1db | 393 | if (p == NULL) { |
| donatien | 0:b802fc31f1db | 394 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 395 | } |
| donatien | 0:b802fc31f1db | 396 | iphdr = (struct ip_hdr *)p->payload; |
| donatien | 0:b802fc31f1db | 397 | #else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */ |
| donatien | 0:b802fc31f1db | 398 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 399 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n", |
| donatien | 0:b802fc31f1db | 400 | ntohs(IPH_OFFSET(iphdr)))); |
| donatien | 0:b802fc31f1db | 401 | IP_STATS_INC(ip.opterr); |
| donatien | 0:b802fc31f1db | 402 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 403 | /* unsupported protocol feature */ |
| donatien | 0:b802fc31f1db | 404 | snmp_inc_ipinunknownprotos(); |
| donatien | 0:b802fc31f1db | 405 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 406 | #endif /* IP_REASSEMBLY */ |
| donatien | 0:b802fc31f1db | 407 | } |
| donatien | 0:b802fc31f1db | 408 | |
| donatien | 0:b802fc31f1db | 409 | #if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */ |
| donatien | 0:b802fc31f1db | 410 | |
| donatien | 0:b802fc31f1db | 411 | #if LWIP_IGMP |
| donatien | 0:b802fc31f1db | 412 | /* there is an extra "router alert" option in IGMP messages which we allow for but do not police */ |
| donatien | 0:b802fc31f1db | 413 | if((iphdr_hlen > IP_HLEN) && (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) { |
| donatien | 0:b802fc31f1db | 414 | #else |
| donatien | 0:b802fc31f1db | 415 | if (iphdr_hlen > IP_HLEN) { |
| donatien | 0:b802fc31f1db | 416 | #endif /* LWIP_IGMP */ |
| donatien | 0:b802fc31f1db | 417 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n")); |
| donatien | 0:b802fc31f1db | 418 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 419 | IP_STATS_INC(ip.opterr); |
| donatien | 0:b802fc31f1db | 420 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 421 | /* unsupported protocol feature */ |
| donatien | 0:b802fc31f1db | 422 | snmp_inc_ipinunknownprotos(); |
| donatien | 0:b802fc31f1db | 423 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 424 | } |
| donatien | 0:b802fc31f1db | 425 | #endif /* IP_OPTIONS_ALLOWED == 0 */ |
| donatien | 0:b802fc31f1db | 426 | |
| donatien | 0:b802fc31f1db | 427 | /* send to upper layers */ |
| donatien | 0:b802fc31f1db | 428 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n")); |
| donatien | 0:b802fc31f1db | 429 | ip_debug_print(p); |
| donatien | 0:b802fc31f1db | 430 | LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len)); |
| donatien | 0:b802fc31f1db | 431 | |
| donatien | 0:b802fc31f1db | 432 | current_netif = inp; |
| donatien | 0:b802fc31f1db | 433 | current_header = iphdr; |
| donatien | 0:b802fc31f1db | 434 | |
| donatien | 0:b802fc31f1db | 435 | #if LWIP_RAW |
| donatien | 0:b802fc31f1db | 436 | /* raw input did not eat the packet? */ |
| donatien | 0:b802fc31f1db | 437 | if (raw_input(p, inp) == 0) |
| donatien | 0:b802fc31f1db | 438 | #endif /* LWIP_RAW */ |
| donatien | 0:b802fc31f1db | 439 | { |
| donatien | 0:b802fc31f1db | 440 | |
| donatien | 0:b802fc31f1db | 441 | switch (IPH_PROTO(iphdr)) { |
| donatien | 0:b802fc31f1db | 442 | #if LWIP_UDP |
| donatien | 0:b802fc31f1db | 443 | case IP_PROTO_UDP: |
| donatien | 0:b802fc31f1db | 444 | #if LWIP_UDPLITE |
| donatien | 0:b802fc31f1db | 445 | case IP_PROTO_UDPLITE: |
| donatien | 0:b802fc31f1db | 446 | #endif /* LWIP_UDPLITE */ |
| donatien | 0:b802fc31f1db | 447 | snmp_inc_ipindelivers(); |
| donatien | 0:b802fc31f1db | 448 | udp_input(p, inp); |
| donatien | 0:b802fc31f1db | 449 | break; |
| donatien | 0:b802fc31f1db | 450 | #endif /* LWIP_UDP */ |
| donatien | 0:b802fc31f1db | 451 | #if LWIP_TCP |
| donatien | 0:b802fc31f1db | 452 | case IP_PROTO_TCP: |
| donatien | 0:b802fc31f1db | 453 | snmp_inc_ipindelivers(); |
| donatien | 0:b802fc31f1db | 454 | tcp_input(p, inp); |
| donatien | 0:b802fc31f1db | 455 | break; |
| donatien | 0:b802fc31f1db | 456 | #endif /* LWIP_TCP */ |
| donatien | 0:b802fc31f1db | 457 | #if LWIP_ICMP |
| donatien | 0:b802fc31f1db | 458 | case IP_PROTO_ICMP: |
| donatien | 0:b802fc31f1db | 459 | snmp_inc_ipindelivers(); |
| donatien | 0:b802fc31f1db | 460 | icmp_input(p, inp); |
| donatien | 0:b802fc31f1db | 461 | break; |
| donatien | 0:b802fc31f1db | 462 | #endif /* LWIP_ICMP */ |
| donatien | 0:b802fc31f1db | 463 | #if LWIP_IGMP |
| donatien | 0:b802fc31f1db | 464 | case IP_PROTO_IGMP: |
| donatien | 0:b802fc31f1db | 465 | igmp_input(p,inp,&(iphdr->dest)); |
| donatien | 0:b802fc31f1db | 466 | break; |
| donatien | 0:b802fc31f1db | 467 | #endif /* LWIP_IGMP */ |
| donatien | 0:b802fc31f1db | 468 | default: |
| donatien | 0:b802fc31f1db | 469 | #if LWIP_ICMP |
| donatien | 0:b802fc31f1db | 470 | /* send ICMP destination protocol unreachable unless is was a broadcast */ |
| donatien | 0:b802fc31f1db | 471 | if (!ip_addr_isbroadcast(&(iphdr->dest), inp) && |
| donatien | 0:b802fc31f1db | 472 | !ip_addr_ismulticast(&(iphdr->dest))) { |
| donatien | 0:b802fc31f1db | 473 | p->payload = iphdr; |
| donatien | 0:b802fc31f1db | 474 | icmp_dest_unreach(p, ICMP_DUR_PROTO); |
| donatien | 0:b802fc31f1db | 475 | } |
| donatien | 0:b802fc31f1db | 476 | #endif /* LWIP_ICMP */ |
| donatien | 0:b802fc31f1db | 477 | pbuf_free(p); |
| donatien | 0:b802fc31f1db | 478 | |
| donatien | 0:b802fc31f1db | 479 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr))); |
| donatien | 0:b802fc31f1db | 480 | |
| donatien | 0:b802fc31f1db | 481 | IP_STATS_INC(ip.proterr); |
| donatien | 0:b802fc31f1db | 482 | IP_STATS_INC(ip.drop); |
| donatien | 0:b802fc31f1db | 483 | snmp_inc_ipinunknownprotos(); |
| donatien | 0:b802fc31f1db | 484 | } |
| donatien | 0:b802fc31f1db | 485 | } |
| donatien | 0:b802fc31f1db | 486 | |
| donatien | 0:b802fc31f1db | 487 | current_netif = NULL; |
| donatien | 0:b802fc31f1db | 488 | current_header = NULL; |
| donatien | 0:b802fc31f1db | 489 | |
| donatien | 0:b802fc31f1db | 490 | return ERR_OK; |
| donatien | 0:b802fc31f1db | 491 | } |
| donatien | 0:b802fc31f1db | 492 | |
| donatien | 0:b802fc31f1db | 493 | /** |
| donatien | 0:b802fc31f1db | 494 | * Sends an IP packet on a network interface. This function constructs |
| donatien | 0:b802fc31f1db | 495 | * the IP header and calculates the IP header checksum. If the source |
| donatien | 0:b802fc31f1db | 496 | * IP address is NULL, the IP address of the outgoing network |
| donatien | 0:b802fc31f1db | 497 | * interface is filled in as source address. |
| donatien | 0:b802fc31f1db | 498 | * If the destination IP address is IP_HDRINCL, p is assumed to already |
| donatien | 0:b802fc31f1db | 499 | * include an IP header and p->payload points to it instead of the data. |
| donatien | 0:b802fc31f1db | 500 | * |
| donatien | 0:b802fc31f1db | 501 | * @param p the packet to send (p->payload points to the data, e.g. next |
| donatien | 0:b802fc31f1db | 502 | protocol header; if dest == IP_HDRINCL, p already includes an IP |
| donatien | 0:b802fc31f1db | 503 | header and p->payload points to that IP header) |
| donatien | 0:b802fc31f1db | 504 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the |
| donatien | 0:b802fc31f1db | 505 | * IP address of the netif used to send is used as source address) |
| donatien | 0:b802fc31f1db | 506 | * @param dest the destination IP address to send the packet to |
| donatien | 0:b802fc31f1db | 507 | * @param ttl the TTL value to be set in the IP header |
| donatien | 0:b802fc31f1db | 508 | * @param tos the TOS value to be set in the IP header |
| donatien | 0:b802fc31f1db | 509 | * @param proto the PROTOCOL to be set in the IP header |
| donatien | 0:b802fc31f1db | 510 | * @param netif the netif on which to send this packet |
| donatien | 0:b802fc31f1db | 511 | * @return ERR_OK if the packet was sent OK |
| donatien | 0:b802fc31f1db | 512 | * ERR_BUF if p doesn't have enough space for IP/LINK headers |
| donatien | 0:b802fc31f1db | 513 | * returns errors returned by netif->output |
| donatien | 0:b802fc31f1db | 514 | * |
| donatien | 0:b802fc31f1db | 515 | * @note ip_id: RFC791 "some host may be able to simply use |
| donatien | 0:b802fc31f1db | 516 | * unique identifiers independent of destination" |
| donatien | 0:b802fc31f1db | 517 | */ |
| donatien | 0:b802fc31f1db | 518 | err_t |
| donatien | 0:b802fc31f1db | 519 | ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, |
| donatien | 0:b802fc31f1db | 520 | u8_t ttl, u8_t tos, |
| donatien | 0:b802fc31f1db | 521 | u8_t proto, struct netif *netif) |
| donatien | 0:b802fc31f1db | 522 | { |
| donatien | 0:b802fc31f1db | 523 | #if IP_OPTIONS_SEND |
| donatien | 0:b802fc31f1db | 524 | return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0); |
| donatien | 0:b802fc31f1db | 525 | } |
| donatien | 0:b802fc31f1db | 526 | |
| donatien | 0:b802fc31f1db | 527 | /** |
| donatien | 0:b802fc31f1db | 528 | * Same as ip_output_if() but with the possibility to include IP options: |
| donatien | 0:b802fc31f1db | 529 | * |
| donatien | 0:b802fc31f1db | 530 | * @ param ip_options pointer to the IP options, copied into the IP header |
| donatien | 0:b802fc31f1db | 531 | * @ param optlen length of ip_options |
| donatien | 0:b802fc31f1db | 532 | */ |
| donatien | 0:b802fc31f1db | 533 | err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, |
| donatien | 0:b802fc31f1db | 534 | u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options, |
| donatien | 0:b802fc31f1db | 535 | u16_t optlen) |
| donatien | 0:b802fc31f1db | 536 | { |
| donatien | 0:b802fc31f1db | 537 | #endif /* IP_OPTIONS_SEND */ |
| donatien | 0:b802fc31f1db | 538 | struct ip_hdr *iphdr; |
| donatien | 0:b802fc31f1db | 539 | static u16_t ip_id = 0; |
| donatien | 0:b802fc31f1db | 540 | |
| donatien | 0:b802fc31f1db | 541 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer |
| donatien | 0:b802fc31f1db | 542 | gets altered as the packet is passed down the stack */ |
| donatien | 0:b802fc31f1db | 543 | LWIP_ASSERT("p->ref == 1", p->ref == 1); |
| donatien | 0:b802fc31f1db | 544 | |
| donatien | 0:b802fc31f1db | 545 | snmp_inc_ipoutrequests(); |
| donatien | 0:b802fc31f1db | 546 | |
| donatien | 0:b802fc31f1db | 547 | /* Should the IP header be generated or is it already included in p? */ |
| donatien | 0:b802fc31f1db | 548 | if (dest != IP_HDRINCL) { |
| donatien | 0:b802fc31f1db | 549 | u16_t ip_hlen = IP_HLEN; |
| donatien | 0:b802fc31f1db | 550 | #if IP_OPTIONS_SEND |
| donatien | 0:b802fc31f1db | 551 | u16_t optlen_aligned = 0; |
| donatien | 0:b802fc31f1db | 552 | if (optlen != 0) { |
| donatien | 0:b802fc31f1db | 553 | /* round up to a multiple of 4 */ |
| donatien | 0:b802fc31f1db | 554 | optlen_aligned = ((optlen + 3) & ~3); |
| donatien | 0:b802fc31f1db | 555 | ip_hlen += optlen_aligned; |
| donatien | 0:b802fc31f1db | 556 | /* First write in the IP options */ |
| donatien | 0:b802fc31f1db | 557 | if (pbuf_header(p, optlen_aligned)) { |
| donatien | 0:b802fc31f1db | 558 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n")); |
| donatien | 0:b802fc31f1db | 559 | IP_STATS_INC(ip.err); |
| donatien | 0:b802fc31f1db | 560 | snmp_inc_ipoutdiscards(); |
| donatien | 0:b802fc31f1db | 561 | return ERR_BUF; |
| donatien | 0:b802fc31f1db | 562 | } |
| donatien | 0:b802fc31f1db | 563 | MEMCPY(p->payload, ip_options, optlen); |
| donatien | 0:b802fc31f1db | 564 | if (optlen < optlen_aligned) { |
| donatien | 0:b802fc31f1db | 565 | /* zero the remaining bytes */ |
| donatien | 0:b802fc31f1db | 566 | memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen); |
| donatien | 0:b802fc31f1db | 567 | } |
| donatien | 0:b802fc31f1db | 568 | } |
| donatien | 0:b802fc31f1db | 569 | #endif /* IP_OPTIONS_SEND */ |
| donatien | 0:b802fc31f1db | 570 | /* generate IP header */ |
| donatien | 0:b802fc31f1db | 571 | if (pbuf_header(p, IP_HLEN)) { |
| donatien | 0:b802fc31f1db | 572 | LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n")); |
| donatien | 0:b802fc31f1db | 573 | |
| donatien | 0:b802fc31f1db | 574 | IP_STATS_INC(ip.err); |
| donatien | 0:b802fc31f1db | 575 | snmp_inc_ipoutdiscards(); |
| donatien | 0:b802fc31f1db | 576 | return ERR_BUF; |
| donatien | 0:b802fc31f1db | 577 | } |
| donatien | 0:b802fc31f1db | 578 | |
| donatien | 0:b802fc31f1db | 579 | iphdr = (struct ip_hdr *)p->payload; |
| donatien | 0:b802fc31f1db | 580 | LWIP_ASSERT("check that first pbuf can hold struct ip_hdr", |
| donatien | 0:b802fc31f1db | 581 | (p->len >= sizeof(struct ip_hdr))); |
| donatien | 0:b802fc31f1db | 582 | |
| donatien | 0:b802fc31f1db | 583 | IPH_TTL_SET(iphdr, ttl); |
| donatien | 0:b802fc31f1db | 584 | IPH_PROTO_SET(iphdr, proto); |
| donatien | 0:b802fc31f1db | 585 | |
| donatien | 0:b802fc31f1db | 586 | /* dest cannot be NULL here */ |
| donatien | 0:b802fc31f1db | 587 | ip_addr_copy(iphdr->dest, *dest); |
| donatien | 0:b802fc31f1db | 588 | |
| donatien | 0:b802fc31f1db | 589 | IPH_VHLTOS_SET(iphdr, 4, ip_hlen / 4, tos); |
| donatien | 0:b802fc31f1db | 590 | IPH_LEN_SET(iphdr, htons(p->tot_len)); |
| donatien | 0:b802fc31f1db | 591 | IPH_OFFSET_SET(iphdr, 0); |
| donatien | 0:b802fc31f1db | 592 | IPH_ID_SET(iphdr, htons(ip_id)); |
| donatien | 0:b802fc31f1db | 593 | ++ip_id; |
| donatien | 0:b802fc31f1db | 594 | |
| donatien | 0:b802fc31f1db | 595 | if (ip_addr_isany(src)) { |
| donatien | 0:b802fc31f1db | 596 | ip_addr_copy(iphdr->src, netif->ip_addr); |
| donatien | 0:b802fc31f1db | 597 | } else { |
| donatien | 0:b802fc31f1db | 598 | /* src cannot be NULL here */ |
| donatien | 0:b802fc31f1db | 599 | ip_addr_copy(iphdr->src, *src); |
| donatien | 0:b802fc31f1db | 600 | } |
| donatien | 0:b802fc31f1db | 601 | |
| donatien | 0:b802fc31f1db | 602 | IPH_CHKSUM_SET(iphdr, 0); |
| donatien | 0:b802fc31f1db | 603 | #if CHECKSUM_GEN_IP |
| donatien | 0:b802fc31f1db | 604 | IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen)); |
| donatien | 0:b802fc31f1db | 605 | #endif |
| donatien | 0:b802fc31f1db | 606 | } else { |
| donatien | 0:b802fc31f1db | 607 | /* IP header already included in p */ |
| donatien | 0:b802fc31f1db | 608 | iphdr = (struct ip_hdr *)p->payload; |
| donatien | 0:b802fc31f1db | 609 | dest = &(iphdr->dest); |
| donatien | 0:b802fc31f1db | 610 | } |
| donatien | 0:b802fc31f1db | 611 | |
| donatien | 0:b802fc31f1db | 612 | IP_STATS_INC(ip.xmit); |
| donatien | 0:b802fc31f1db | 613 | |
| donatien | 0:b802fc31f1db | 614 | LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num)); |
| donatien | 0:b802fc31f1db | 615 | ip_debug_print(p); |
| donatien | 0:b802fc31f1db | 616 | |
| donatien | 0:b802fc31f1db | 617 | #if ENABLE_LOOPBACK |
| donatien | 0:b802fc31f1db | 618 | if (ip_addr_cmp(dest, &netif->ip_addr)) { |
| donatien | 0:b802fc31f1db | 619 | /* Packet to self, enqueue it for loopback */ |
| donatien | 0:b802fc31f1db | 620 | LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()")); |
| donatien | 0:b802fc31f1db | 621 | return netif_loop_output(netif, p, dest); |
| donatien | 0:b802fc31f1db | 622 | } |
| donatien | 0:b802fc31f1db | 623 | #endif /* ENABLE_LOOPBACK */ |
| donatien | 0:b802fc31f1db | 624 | #if IP_FRAG |
| donatien | 0:b802fc31f1db | 625 | /* don't fragment if interface has mtu set to 0 [loopif] */ |
| donatien | 0:b802fc31f1db | 626 | if (netif->mtu && (p->tot_len > netif->mtu)) { |
| donatien | 0:b802fc31f1db | 627 | return ip_frag(p,netif,dest); |
| donatien | 0:b802fc31f1db | 628 | } |
| donatien | 0:b802fc31f1db | 629 | #endif |
| donatien | 0:b802fc31f1db | 630 | |
| donatien | 0:b802fc31f1db | 631 | LWIP_DEBUGF(IP_DEBUG, ("netif->output()")); |
| donatien | 0:b802fc31f1db | 632 | return netif->output(netif, p, dest); |
| donatien | 0:b802fc31f1db | 633 | } |
| donatien | 0:b802fc31f1db | 634 | |
| donatien | 0:b802fc31f1db | 635 | /** |
| donatien | 0:b802fc31f1db | 636 | * Simple interface to ip_output_if. It finds the outgoing network |
| donatien | 0:b802fc31f1db | 637 | * interface and calls upon ip_output_if to do the actual work. |
| donatien | 0:b802fc31f1db | 638 | * |
| donatien | 0:b802fc31f1db | 639 | * @param p the packet to send (p->payload points to the data, e.g. next |
| donatien | 0:b802fc31f1db | 640 | protocol header; if dest == IP_HDRINCL, p already includes an IP |
| donatien | 0:b802fc31f1db | 641 | header and p->payload points to that IP header) |
| donatien | 0:b802fc31f1db | 642 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the |
| donatien | 0:b802fc31f1db | 643 | * IP address of the netif used to send is used as source address) |
| donatien | 0:b802fc31f1db | 644 | * @param dest the destination IP address to send the packet to |
| donatien | 0:b802fc31f1db | 645 | * @param ttl the TTL value to be set in the IP header |
| donatien | 0:b802fc31f1db | 646 | * @param tos the TOS value to be set in the IP header |
| donatien | 0:b802fc31f1db | 647 | * @param proto the PROTOCOL to be set in the IP header |
| donatien | 0:b802fc31f1db | 648 | * |
| donatien | 0:b802fc31f1db | 649 | * @return ERR_RTE if no route is found |
| donatien | 0:b802fc31f1db | 650 | * see ip_output_if() for more return values |
| donatien | 0:b802fc31f1db | 651 | */ |
| donatien | 0:b802fc31f1db | 652 | err_t |
| donatien | 0:b802fc31f1db | 653 | ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, |
| donatien | 0:b802fc31f1db | 654 | u8_t ttl, u8_t tos, u8_t proto) |
| donatien | 0:b802fc31f1db | 655 | { |
| donatien | 0:b802fc31f1db | 656 | struct netif *netif; |
| donatien | 0:b802fc31f1db | 657 | |
| donatien | 0:b802fc31f1db | 658 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer |
| donatien | 0:b802fc31f1db | 659 | gets altered as the packet is passed down the stack */ |
| donatien | 0:b802fc31f1db | 660 | LWIP_ASSERT("p->ref == 1", p->ref == 1); |
| donatien | 0:b802fc31f1db | 661 | |
| donatien | 0:b802fc31f1db | 662 | if ((netif = ip_route(dest)) == NULL) { |
| donatien | 0:b802fc31f1db | 663 | LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", |
| donatien | 0:b802fc31f1db | 664 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); |
| donatien | 0:b802fc31f1db | 665 | IP_STATS_INC(ip.rterr); |
| donatien | 0:b802fc31f1db | 666 | return ERR_RTE; |
| donatien | 0:b802fc31f1db | 667 | } |
| donatien | 0:b802fc31f1db | 668 | |
| donatien | 0:b802fc31f1db | 669 | return ip_output_if(p, src, dest, ttl, tos, proto, netif); |
| donatien | 0:b802fc31f1db | 670 | } |
| donatien | 0:b802fc31f1db | 671 | |
| donatien | 0:b802fc31f1db | 672 | #if LWIP_NETIF_HWADDRHINT |
| donatien | 0:b802fc31f1db | 673 | /** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint |
| donatien | 0:b802fc31f1db | 674 | * before calling ip_output_if. |
| donatien | 0:b802fc31f1db | 675 | * |
| donatien | 0:b802fc31f1db | 676 | * @param p the packet to send (p->payload points to the data, e.g. next |
| donatien | 0:b802fc31f1db | 677 | protocol header; if dest == IP_HDRINCL, p already includes an IP |
| donatien | 0:b802fc31f1db | 678 | header and p->payload points to that IP header) |
| donatien | 0:b802fc31f1db | 679 | * @param src the source IP address to send from (if src == IP_ADDR_ANY, the |
| donatien | 0:b802fc31f1db | 680 | * IP address of the netif used to send is used as source address) |
| donatien | 0:b802fc31f1db | 681 | * @param dest the destination IP address to send the packet to |
| donatien | 0:b802fc31f1db | 682 | * @param ttl the TTL value to be set in the IP header |
| donatien | 0:b802fc31f1db | 683 | * @param tos the TOS value to be set in the IP header |
| donatien | 0:b802fc31f1db | 684 | * @param proto the PROTOCOL to be set in the IP header |
| donatien | 0:b802fc31f1db | 685 | * @param addr_hint address hint pointer set to netif->addr_hint before |
| donatien | 0:b802fc31f1db | 686 | * calling ip_output_if() |
| donatien | 0:b802fc31f1db | 687 | * |
| donatien | 0:b802fc31f1db | 688 | * @return ERR_RTE if no route is found |
| donatien | 0:b802fc31f1db | 689 | * see ip_output_if() for more return values |
| donatien | 0:b802fc31f1db | 690 | */ |
| donatien | 0:b802fc31f1db | 691 | err_t |
| donatien | 0:b802fc31f1db | 692 | ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, |
| donatien | 0:b802fc31f1db | 693 | u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint) |
| donatien | 0:b802fc31f1db | 694 | { |
| donatien | 0:b802fc31f1db | 695 | struct netif *netif; |
| donatien | 0:b802fc31f1db | 696 | err_t err; |
| donatien | 0:b802fc31f1db | 697 | |
| donatien | 0:b802fc31f1db | 698 | /* pbufs passed to IP must have a ref-count of 1 as their payload pointer |
| donatien | 0:b802fc31f1db | 699 | gets altered as the packet is passed down the stack */ |
| donatien | 0:b802fc31f1db | 700 | LWIP_ASSERT("p->ref == 1", p->ref == 1); |
| donatien | 0:b802fc31f1db | 701 | |
| donatien | 0:b802fc31f1db | 702 | if ((netif = ip_route(dest)) == NULL) { |
| donatien | 0:b802fc31f1db | 703 | LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", |
| donatien | 0:b802fc31f1db | 704 | ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest))); |
| donatien | 0:b802fc31f1db | 705 | IP_STATS_INC(ip.rterr); |
| donatien | 0:b802fc31f1db | 706 | return ERR_RTE; |
| donatien | 0:b802fc31f1db | 707 | } |
| donatien | 0:b802fc31f1db | 708 | |
| donatien | 0:b802fc31f1db | 709 | netif->addr_hint = addr_hint; |
| donatien | 0:b802fc31f1db | 710 | err = ip_output_if(p, src, dest, ttl, tos, proto, netif); |
| donatien | 0:b802fc31f1db | 711 | netif->addr_hint = NULL; |
| donatien | 0:b802fc31f1db | 712 | |
| donatien | 0:b802fc31f1db | 713 | return err; |
| donatien | 0:b802fc31f1db | 714 | } |
| donatien | 0:b802fc31f1db | 715 | #endif /* LWIP_NETIF_HWADDRHINT*/ |
| donatien | 0:b802fc31f1db | 716 | |
| donatien | 0:b802fc31f1db | 717 | #if IP_DEBUG |
| donatien | 0:b802fc31f1db | 718 | /* Print an IP header by using LWIP_DEBUGF |
| donatien | 0:b802fc31f1db | 719 | * @param p an IP packet, p->payload pointing to the IP header |
| donatien | 0:b802fc31f1db | 720 | */ |
| donatien | 0:b802fc31f1db | 721 | void |
| donatien | 0:b802fc31f1db | 722 | ip_debug_print(struct pbuf *p) |
| donatien | 0:b802fc31f1db | 723 | { |
| donatien | 0:b802fc31f1db | 724 | struct ip_hdr *iphdr = (struct ip_hdr *) p->payload; |
| donatien | 0:b802fc31f1db | 725 | u8_t *payload; |
| donatien | 0:b802fc31f1db | 726 | |
| donatien | 0:b802fc31f1db | 727 | payload = (u8_t *)iphdr + IP_HLEN; |
| donatien | 0:b802fc31f1db | 728 | |
| donatien | 0:b802fc31f1db | 729 | LWIP_DEBUGF(IP_DEBUG, ("IP header:\n")); |
| donatien | 0:b802fc31f1db | 730 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 731 | LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n", |
| donatien | 0:b802fc31f1db | 732 | IPH_V(iphdr), |
| donatien | 0:b802fc31f1db | 733 | IPH_HL(iphdr), |
| donatien | 0:b802fc31f1db | 734 | IPH_TOS(iphdr), |
| donatien | 0:b802fc31f1db | 735 | ntohs(IPH_LEN(iphdr)))); |
| donatien | 0:b802fc31f1db | 736 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 737 | LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" |%"U16_F"%"U16_F"%"U16_F"| %4"U16_F" | (id, flags, offset)\n", |
| donatien | 0:b802fc31f1db | 738 | ntohs(IPH_ID(iphdr)), |
| donatien | 0:b802fc31f1db | 739 | ntohs(IPH_OFFSET(iphdr)) >> 15 & 1, |
| donatien | 0:b802fc31f1db | 740 | ntohs(IPH_OFFSET(iphdr)) >> 14 & 1, |
| donatien | 0:b802fc31f1db | 741 | ntohs(IPH_OFFSET(iphdr)) >> 13 & 1, |
| donatien | 0:b802fc31f1db | 742 | ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)); |
| donatien | 0:b802fc31f1db | 743 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 744 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | 0x%04"X16_F" | (ttl, proto, chksum)\n", |
| donatien | 0:b802fc31f1db | 745 | IPH_TTL(iphdr), |
| donatien | 0:b802fc31f1db | 746 | IPH_PROTO(iphdr), |
| donatien | 0:b802fc31f1db | 747 | ntohs(IPH_CHKSUM(iphdr)))); |
| donatien | 0:b802fc31f1db | 748 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 749 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (src)\n", |
| donatien | 0:b802fc31f1db | 750 | ip4_addr1_16(&iphdr->src), |
| donatien | 0:b802fc31f1db | 751 | ip4_addr2_16(&iphdr->src), |
| donatien | 0:b802fc31f1db | 752 | ip4_addr3_16(&iphdr->src), |
| donatien | 0:b802fc31f1db | 753 | ip4_addr4_16(&iphdr->src))); |
| donatien | 0:b802fc31f1db | 754 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 755 | LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n", |
| donatien | 0:b802fc31f1db | 756 | ip4_addr1_16(&iphdr->dest), |
| donatien | 0:b802fc31f1db | 757 | ip4_addr2_16(&iphdr->dest), |
| donatien | 0:b802fc31f1db | 758 | ip4_addr3_16(&iphdr->dest), |
| donatien | 0:b802fc31f1db | 759 | ip4_addr4_16(&iphdr->dest))); |
| donatien | 0:b802fc31f1db | 760 | LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); |
| donatien | 0:b802fc31f1db | 761 | } |
| donatien | 0:b802fc31f1db | 762 | #endif /* IP_DEBUG */ |