/* | |
* Copyright (c) 2001-2004 Swedish Institute of Computer Science. | |
* All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without modification, | |
* are permitted provided that the following conditions are met: | |
* | |
* 1. Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright notice, | |
* this list of conditions and the following disclaimer in the documentation | |
* and/or other materials provided with the distribution. | |
* 3. The name of the author may not be used to endorse or promote products | |
* derived from this software without specific prior written permission. | |
* | |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED | |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT | |
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT | |
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING | |
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY | |
* OF SUCH DAMAGE. | |
* | |
* This file is part of the lwIP TCP/IP stack. | |
* | |
* Author: Adam Dunkels <adam@sics.se> | |
* | |
*/ | |
/* ip.c | |
* | |
* This is the code for the IP layer for IPv6. | |
* | |
*/ | |
#include "lwip/opt.h" | |
#include "lwip/def.h" | |
#include "lwip/mem.h" | |
#include "lwip/ip.h" | |
#include "lwip/inet.h" | |
#include "lwip/netif.h" | |
#include "lwip/icmp.h" | |
#include "lwip/udp.h" | |
#include "lwip/tcp.h" | |
#include "lwip/stats.h" | |
#include "arch/perf.h" | |
/* ip_init: | |
* | |
* Initializes the IP layer. | |
*/ | |
void | |
ip_init(void) | |
{ | |
} | |
/* ip_route: | |
* | |
* Finds the appropriate network interface for a given IP address. It searches the | |
* list of network interfaces linearly. A match is found if the masked IP address of | |
* the network interface equals the masked IP address given to the function. | |
*/ | |
struct netif * | |
ip_route(struct ip_addr *dest) | |
{ | |
struct netif *netif; | |
for(netif = netif_list; netif != NULL; netif = netif->next) { | |
if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) { | |
return netif; | |
} | |
} | |
return netif_default; | |
} | |
/* ip_forward: | |
* | |
* Forwards an IP packet. It finds an appropriate route for the packet, decrements | |
* the TTL value of the packet, adjusts the checksum and outputs the packet on the | |
* appropriate interface. | |
*/ | |
static void | |
ip_forward(struct pbuf *p, struct ip_hdr *iphdr) | |
{ | |
struct netif *netif; | |
PERF_START; | |
if ((netif = ip_route((struct ip_addr *)&(iphdr->dest))) == NULL) { | |
LWIP_DEBUGF(IP_DEBUG, ("ip_input: no forwarding route found for ")); | |
#if IP_DEBUG | |
ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest))); | |
#endif /* IP_DEBUG */ | |
LWIP_DEBUGF(IP_DEBUG, ("\n")); | |
pbuf_free(p); | |
return; | |
} | |
/* Decrement TTL and send ICMP if ttl == 0. */ | |
if (--iphdr->hoplim == 0) { | |
#if LWIP_ICMP | |
/* Don't send ICMP messages in response to ICMP messages */ | |
if (iphdr->nexthdr != IP_PROTO_ICMP) { | |
icmp_time_exceeded(p, ICMP_TE_TTL); | |
} | |
#endif /* LWIP_ICMP */ | |
pbuf_free(p); | |
return; | |
} | |
/* Incremental update of the IP checksum. */ | |
/* if (iphdr->chksum >= htons(0xffff - 0x100)) { | |
iphdr->chksum += htons(0x100) + 1; | |
} else { | |
iphdr->chksum += htons(0x100); | |
}*/ | |
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to ")); | |
#if IP_DEBUG | |
ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest))); | |
#endif /* IP_DEBUG */ | |
LWIP_DEBUGF(IP_DEBUG, ("\n")); | |
IP_STATS_INC(ip.fw); | |
IP_STATS_INC(ip.xmit); | |
PERF_STOP("ip_forward"); | |
netif->output(netif, p, (struct ip_addr *)&(iphdr->dest)); | |
} | |
/* ip_input: | |
* | |
* This function is called by the network interface device driver when an IP packet is | |
* received. The function does the basic checks of the IP header such as packet size | |
* being at least larger than the header size etc. If the packet was not destined for | |
* us, the packet is forwarded (using ip_forward). The IP checksum is always checked. | |
* | |
* Finally, the packet is sent to the upper layer protocol input function. | |
*/ | |
void | |
ip_input(struct pbuf *p, struct netif *inp) { | |
struct ip_hdr *iphdr; | |
struct netif *netif; | |
PERF_START; | |
#if IP_DEBUG | |
ip_debug_print(p); | |
#endif /* IP_DEBUG */ | |
IP_STATS_INC(ip.recv); | |
/* identify the IP header */ | |
iphdr = p->payload; | |
if (iphdr->v != 6) { | |
LWIP_DEBUGF(IP_DEBUG, ("IP packet dropped due to bad version number\n")); | |
#if IP_DEBUG | |
ip_debug_print(p); | |
#endif /* IP_DEBUG */ | |
pbuf_free(p); | |
IP_STATS_INC(ip.err); | |
IP_STATS_INC(ip.drop); | |
return; | |
} | |
/* is this packet for us? */ | |
for(netif = netif_list; netif != NULL; netif = netif->next) { | |
#if IP_DEBUG | |
LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest ")); | |
ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest))); | |
LWIP_DEBUGF(IP_DEBUG, ("netif->ip_addr ")); | |
ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest))); | |
LWIP_DEBUGF(IP_DEBUG, ("\n")); | |
#endif /* IP_DEBUG */ | |
if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr))) { | |
break; | |
} | |
} | |
if (netif == NULL) { | |
/* packet not for us, route or discard */ | |
#if IP_FORWARD | |
ip_forward(p, iphdr); | |
#endif | |
pbuf_free(p); | |
return; | |
} | |
pbuf_realloc(p, IP_HLEN + ntohs(iphdr->len)); | |
/* send to upper layers */ | |
#if IP_DEBUG | |
/* LWIP_DEBUGF("ip_input: \n"); | |
ip_debug_print(p); | |
LWIP_DEBUGF("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len);*/ | |
#endif /* IP_DEBUG */ | |
if(pbuf_header(p, -IP_HLEN)) { | |
LWIP_ASSERT("Can't move over header in packet", 0); | |
return; | |
} | |
switch (iphdr->nexthdr) { | |
case IP_PROTO_UDP: | |
udp_input(p, inp); | |
break; | |
case IP_PROTO_TCP: | |
tcp_input(p, inp); | |
break; | |
#if LWIP_ICMP | |
case IP_PROTO_ICMP: | |
icmp_input(p, inp); | |
break; | |
#endif /* LWIP_ICMP */ | |
default: | |
#if LWIP_ICMP | |
/* send ICMP destination protocol unreachable */ | |
icmp_dest_unreach(p, ICMP_DUR_PROTO); | |
#endif /* LWIP_ICMP */ | |
pbuf_free(p); | |
LWIP_DEBUGF(IP_DEBUG, ("Unsupported transport protocol %"U16_F"\n", | |
iphdr->nexthdr)); | |
IP_STATS_INC(ip.proterr); | |
IP_STATS_INC(ip.drop); | |
} | |
PERF_STOP("ip_input"); | |
} | |
/* ip_output_if: | |
* | |
* Sends an IP packet on a network interface. This function constructs the IP header | |
* and calculates the IP header checksum. If the source IP address is NULL, | |
* the IP address of the outgoing network interface is filled in as source address. | |
*/ | |
err_t | |
ip_output_if (struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, | |
u8_t ttl, | |
u8_t proto, struct netif *netif) | |
{ | |
struct ip_hdr *iphdr; | |
PERF_START; | |
LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len)); | |
if (pbuf_header(p, IP_HLEN)) { | |
LWIP_DEBUGF(IP_DEBUG, ("ip_output: not enough room for IP header in pbuf\n")); | |
IP_STATS_INC(ip.err); | |
return ERR_BUF; | |
} | |
LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len)); | |
iphdr = p->payload; | |
if (dest != IP_HDRINCL) { | |
LWIP_DEBUGF(IP_DEBUG, ("!IP_HDRLINCL\n")); | |
iphdr->hoplim = ttl; | |
iphdr->nexthdr = proto; | |
iphdr->len = htons(p->tot_len - IP_HLEN); | |
ip_addr_set(&(iphdr->dest), dest); | |
iphdr->v = 6; | |
if (ip_addr_isany(src)) { | |
ip_addr_set(&(iphdr->src), &(netif->ip_addr)); | |
} else { | |
ip_addr_set(&(iphdr->src), src); | |
} | |
} else { | |
dest = &(iphdr->dest); | |
} | |
IP_STATS_INC(ip.xmit); | |
LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c (len %"U16_F")\n", netif->name[0], netif->name[1], p->tot_len)); | |
#if IP_DEBUG | |
ip_debug_print(p); | |
#endif /* IP_DEBUG */ | |
PERF_STOP("ip_output_if"); | |
return netif->output(netif, p, dest); | |
} | |
/* ip_output: | |
* | |
* Simple interface to ip_output_if. It finds the outgoing network interface and | |
* calls upon ip_output_if to do the actual work. | |
*/ | |
err_t | |
ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, | |
u8_t ttl, u8_t proto) | |
{ | |
struct netif *netif; | |
if ((netif = ip_route(dest)) == NULL) { | |
LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr)); | |
IP_STATS_INC(ip.rterr); | |
return ERR_RTE; | |
} | |
return ip_output_if (p, src, dest, ttl, proto, netif); | |
} | |
#if IP_DEBUG | |
void | |
ip_debug_print(struct pbuf *p) | |
{ | |
struct ip_hdr *iphdr = p->payload; | |
LWIP_DEBUGF(IP_DEBUG, ("IP header:\n")); | |
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); | |
LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" | %"X16_F"%"X16_F" | %"X16_F"%"X16_F" | (v, traffic class, flow label)\n", | |
iphdr->v, | |
iphdr->tclass1, iphdr->tclass2, | |
iphdr->flow1, iphdr->flow2)); | |
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); | |
LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" | %2"U16_F" | %2"U16_F" | (len, nexthdr, hoplim)\n", | |
ntohs(iphdr->len), | |
iphdr->nexthdr, | |
iphdr->hoplim)); | |
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n", | |
(ntohl(iphdr->src.addr[0]) >> 16) & 0xffff, | |
ntohl(iphdr->src.addr[0]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n", | |
(ntohl(iphdr->src.addr[1]) >> 16) & 0xffff, | |
ntohl(iphdr->src.addr[1]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n", | |
(ntohl(iphdr->src.addr[2]) >> 16) & 0xffff, | |
ntohl(iphdr->src.addr[2]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (src)\n", | |
(ntohl(iphdr->src.addr[3]) >> 16) & 0xffff, | |
ntohl(iphdr->src.addr[3]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n", | |
(ntohl(iphdr->dest.addr[0]) >> 16) & 0xffff, | |
ntohl(iphdr->dest.addr[0]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n", | |
(ntohl(iphdr->dest.addr[1]) >> 16) & 0xffff, | |
ntohl(iphdr->dest.addr[1]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n", | |
(ntohl(iphdr->dest.addr[2]) >> 16) & 0xffff, | |
ntohl(iphdr->dest.addr[2]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("| %4"X32_F" | %4"X32_F" | (dest)\n", | |
(ntohl(iphdr->dest.addr[3]) >> 16) & 0xffff, | |
ntohl(iphdr->dest.addr[3]) & 0xffff)); | |
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n")); | |
} | |
#endif /* IP_DEBUG */ |