added support for lwip

This commit is contained in:
John Cobb
2015-02-15 16:35:01 -06:00
parent 86eb8f94ef
commit 0c07499e54
106 changed files with 41425 additions and 0 deletions

202
lwip/core/ipv4/icmp.c Normal file
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/*
* 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>
*
*/
/* Some ICMP messages should be passed to the transport protocols. This
is not implemented. */
#include <string.h>
#include "lwip/opt.h"
#include "lwip/icmp.h"
#include "lwip/inet.h"
#include "lwip/ip.h"
#include "lwip/def.h"
#include "lwip/stats.h"
#include "lwip/snmp.h"
void
icmp_input(struct pbuf *p, struct netif *inp)
{
u8_t type;
u8_t code;
struct icmp_echo_hdr *iecho;
struct ip_hdr *iphdr;
struct ip_addr tmpaddr;
u16_t hlen;
ICMP_STATS_INC(icmp.recv);
snmp_inc_icmpinmsgs();
iphdr = p->payload;
hlen = IPH_HL(iphdr) * 4;
if (pbuf_header(p, -((s16_t)hlen)) || (p->tot_len < sizeof(u16_t)*2)) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: short ICMP (%"U16_F" bytes) received\n", p->tot_len));
pbuf_free(p);
ICMP_STATS_INC(icmp.lenerr);
snmp_inc_icmpinerrors();
return;
}
type = *((u8_t *)p->payload);
code = *(((u8_t *)p->payload)+1);
switch (type) {
case ICMP_ECHO:
/* broadcast or multicast destination address? */
if (ip_addr_isbroadcast(&iphdr->dest, inp) || ip_addr_ismulticast(&iphdr->dest)) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: Not echoing to multicast or broadcast pings\n"));
ICMP_STATS_INC(icmp.err);
pbuf_free(p);
return;
}
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ping\n"));
if (p->tot_len < sizeof(struct icmp_echo_hdr)) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: bad ICMP echo received\n"));
pbuf_free(p);
ICMP_STATS_INC(icmp.lenerr);
snmp_inc_icmpinerrors();
return;
}
iecho = p->payload;
if (inet_chksum_pbuf(p) != 0) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: checksum failed for received ICMP echo\n"));
pbuf_free(p);
ICMP_STATS_INC(icmp.chkerr);
snmp_inc_icmpinerrors();
return;
}
tmpaddr.addr = iphdr->src.addr;
iphdr->src.addr = iphdr->dest.addr;
iphdr->dest.addr = tmpaddr.addr;
ICMPH_TYPE_SET(iecho, ICMP_ER);
/* adjust the checksum */
if (iecho->chksum >= htons(0xffff - (ICMP_ECHO << 8))) {
iecho->chksum += htons(ICMP_ECHO << 8) + 1;
} else {
iecho->chksum += htons(ICMP_ECHO << 8);
}
ICMP_STATS_INC(icmp.xmit);
/* increase number of messages attempted to send */
snmp_inc_icmpoutmsgs();
/* increase number of echo replies attempted to send */
snmp_inc_icmpoutechoreps();
pbuf_header(p, hlen);
ip_output_if(p, &(iphdr->src), IP_HDRINCL,
IPH_TTL(iphdr), 0, IP_PROTO_ICMP, inp);
break;
default:
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ICMP type %"S16_F" code %"S16_F" not supported.\n", (s16_t)type, (s16_t)code));
ICMP_STATS_INC(icmp.proterr);
ICMP_STATS_INC(icmp.drop);
}
pbuf_free(p);
}
void
icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t)
{
struct pbuf *q;
struct ip_hdr *iphdr;
struct icmp_dur_hdr *idur;
q = pbuf_alloc(PBUF_IP, 8 + IP_HLEN + 8, PBUF_RAM);
/* ICMP header + IP header + 8 bytes of data */
iphdr = p->payload;
idur = q->payload;
ICMPH_TYPE_SET(idur, ICMP_DUR);
ICMPH_CODE_SET(idur, t);
memcpy((u8_t *)q->payload + 8, p->payload, IP_HLEN + 8);
/* calculate checksum */
idur->chksum = 0;
idur->chksum = inet_chksum(idur, q->len);
ICMP_STATS_INC(icmp.xmit);
/* increase number of messages attempted to send */
snmp_inc_icmpoutmsgs();
/* increase number of destination unreachable messages attempted to send */
snmp_inc_icmpoutdestunreachs();
ip_output(q, NULL, &(iphdr->src),
ICMP_TTL, 0, IP_PROTO_ICMP);
pbuf_free(q);
}
#if IP_FORWARD
void
icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t)
{
struct pbuf *q;
struct ip_hdr *iphdr;
struct icmp_te_hdr *tehdr;
q = pbuf_alloc(PBUF_IP, 8 + IP_HLEN + 8, PBUF_RAM);
iphdr = p->payload;
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded from "));
ip_addr_debug_print(ICMP_DEBUG, &(iphdr->src));
LWIP_DEBUGF(ICMP_DEBUG, (" to "));
ip_addr_debug_print(ICMP_DEBUG, &(iphdr->dest));
LWIP_DEBUGF(ICMP_DEBUG, ("\n"));
tehdr = q->payload;
ICMPH_TYPE_SET(tehdr, ICMP_TE);
ICMPH_CODE_SET(tehdr, t);
/* copy fields from original packet */
memcpy((u8_t *)q->payload + 8, (u8_t *)p->payload, IP_HLEN + 8);
/* calculate checksum */
tehdr->chksum = 0;
tehdr->chksum = inet_chksum(tehdr, q->len);
ICMP_STATS_INC(icmp.xmit);
/* increase number of messages attempted to send */
snmp_inc_icmpoutmsgs();
/* increase number of destination unreachable messages attempted to send */
snmp_inc_icmpouttimeexcds();
ip_output(q, NULL, &(iphdr->src),
ICMP_TTL, 0, IP_PROTO_ICMP);
pbuf_free(q);
}
#endif /* IP_FORWARD */

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lwip/core/ipv4/ip.c Normal file
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/* @file
*
* This is the IP layer implementation for incoming and outgoing IP traffic.
*
* @see ip_frag.c
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/ip.h"
#include "lwip/ip_frag.h"
#include "lwip/inet.h"
#include "lwip/netif.h"
#include "lwip/icmp.h"
#include "lwip/raw.h"
#include "lwip/udp.h"
#include "lwip/tcp.h"
#include "lwip/stats.h"
#include "arch/perf.h"
#include "lwip/snmp.h"
#if LWIP_DHCP
# include "lwip/dhcp.h"
#endif /* LWIP_DHCP */
/**
* Initializes the IP layer.
*/
void
ip_init(void)
{
#if IP_FRAG
ip_frag_init();
#endif
}
/**
* Finds the appropriate network interface for a given IP address. It
* searches the list of network interfaces linearly. A match is found
* if the masked IP address of the network interface equals the masked
* IP address given to the function.
*/
struct netif *
ip_route(struct ip_addr *dest)
{
struct netif *netif;
/* iterate through netifs */
for(netif = netif_list; netif != NULL; netif = netif->next) {
/* network mask matches? */
if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
/* return netif on which to forward IP packet */
return netif;
}
}
/* no matching netif found, use default netif */
return netif_default;
}
#if 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 struct netif *
ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
{
struct netif *netif;
PERF_START;
/* Find network interface where to forward this IP packet to. */
netif = ip_route((struct ip_addr *)&(iphdr->dest));
if (netif == NULL) {
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for 0x%"X32_F" found\n",
iphdr->dest.addr));
snmp_inc_ipoutnoroutes();
return (struct netif *)NULL;
}
/* Do not forward packets onto the same network interface on which
* they arrived. */
if (netif == inp) {
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
snmp_inc_ipoutnoroutes();
return (struct netif *)NULL;
}
/* decrement TTL */
IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
/* send ICMP if TTL == 0 */
if (IPH_TTL(iphdr) == 0) {
snmp_inc_ipinhdrerrors();
/* Don't send ICMP messages in response to ICMP messages */
if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
icmp_time_exceeded(p, ICMP_TE_TTL);
}
return (struct netif *)NULL;
}
/* Incrementally update the IP checksum. */
if (IPH_CHKSUM(iphdr) >= htons(0xffff - 0x100)) {
IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + htons(0x100) + 1);
} else {
IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + htons(0x100));
}
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to 0x%"X32_F"\n",
iphdr->dest.addr));
IP_STATS_INC(ip.fw);
IP_STATS_INC(ip.xmit);
snmp_inc_ipforwdatagrams();
PERF_STOP("ip_forward");
/* transmit pbuf on chosen interface */
netif->output(netif, p, (struct ip_addr *)&(iphdr->dest));
return netif;
}
#endif /* IP_FORWARD */
/**
* This function is called by the network interface device driver when
* an IP packet is received. The function does the basic checks of the
* IP header such as packet size being at least larger than the header
* size etc. If the packet was not destined for us, the packet is
* forwarded (using ip_forward). The IP checksum is always checked.
*
* Finally, the packet is sent to the upper layer protocol input function.
*
*
*
*/
err_t
ip_input(struct pbuf *p, struct netif *inp) {
struct ip_hdr *iphdr;
struct netif *netif;
u16_t iphdrlen;
IP_STATS_INC(ip.recv);
snmp_inc_ipinreceives();
/* identify the IP header */
iphdr = p->payload;
if (IPH_V(iphdr) != 4) {
LWIP_DEBUGF(IP_DEBUG | 1, ("IP packet dropped due to bad version number %"U16_F"\n", IPH_V(iphdr)));
ip_debug_print(p);
pbuf_free(p);
IP_STATS_INC(ip.err);
IP_STATS_INC(ip.drop);
snmp_inc_ipinhdrerrors();
return ERR_OK;
}
/* obtain IP header length in number of 32-bit words */
iphdrlen = IPH_HL(iphdr);
/* calculate IP header length in bytes */
iphdrlen *= 4;
/* header length exceeds first pbuf length? */
if (iphdrlen > p->len) {
LWIP_DEBUGF(IP_DEBUG | 2, ("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet droppped.\n",
iphdrlen, p->len));
/* free (drop) packet pbufs */
pbuf_free(p);
IP_STATS_INC(ip.lenerr);
IP_STATS_INC(ip.drop);
snmp_inc_ipindiscards();
return ERR_OK;
}
/* verify checksum */
#if CHECKSUM_CHECK_IP
if (inet_chksum(iphdr, iphdrlen) != 0) {
LWIP_DEBUGF(IP_DEBUG | 2, ("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdrlen)));
ip_debug_print(p);
pbuf_free(p);
IP_STATS_INC(ip.chkerr);
IP_STATS_INC(ip.drop);
snmp_inc_ipinhdrerrors();
return ERR_OK;
}
#endif
/* Trim pbuf. This should have been done at the netif layer,
* but we'll do it anyway just to be sure that its done. */
pbuf_realloc(p, ntohs(IPH_LEN(iphdr)));
/* match packet against an interface, i.e. is this packet for us? */
for (netif = netif_list; netif != NULL; netif = netif->next) {
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",
iphdr->dest.addr, netif->ip_addr.addr,
iphdr->dest.addr & netif->netmask.addr,
netif->ip_addr.addr & netif->netmask.addr,
iphdr->dest.addr & ~(netif->netmask.addr)));
/* interface is up and configured? */
if ((netif_is_up(netif)) && (!ip_addr_isany(&(netif->ip_addr))))
{
/* unicast to this interface address? */
if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr)) ||
/* or broadcast on this interface network address? */
ip_addr_isbroadcast(&(iphdr->dest), netif)) {
LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet accepted on interface %c%c\n",
netif->name[0], netif->name[1]));
/* break out of for loop */
break;
}
}
}
#if LWIP_DHCP
/* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
* using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
* According to RFC 1542 section 3.1.1, referred by RFC 2131).
*/
if (netif == NULL) {
/* remote port is DHCP server? */
if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
LWIP_DEBUGF(IP_DEBUG | DBG_TRACE | 1, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
ntohs(((struct udp_hdr *)((u8_t *)iphdr + iphdrlen))->dest)));
if (ntohs(((struct udp_hdr *)((u8_t *)iphdr + iphdrlen))->dest) == DHCP_CLIENT_PORT) {
LWIP_DEBUGF(IP_DEBUG | DBG_TRACE | 1, ("ip_input: DHCP packet accepted.\n"));
netif = inp;
}
}
}
#endif /* LWIP_DHCP */
/* packet not for us? */
if (netif == NULL) {
/* packet not for us, route or discard */
LWIP_DEBUGF(IP_DEBUG | DBG_TRACE | 1, ("ip_input: packet not for us.\n"));
#if IP_FORWARD
/* non-broadcast packet? */
if (!ip_addr_isbroadcast(&(iphdr->dest), inp)) {
/* try to forward IP packet on (other) interfaces */
ip_forward(p, iphdr, inp);
}
else
#endif /* IP_FORWARD */
{
snmp_inc_ipinaddrerrors();
snmp_inc_ipindiscards();
}
pbuf_free(p);
return ERR_OK;
}
/* packet consists of multiple fragments? */
if ((IPH_OFFSET(iphdr) & htons(IP_OFFMASK | IP_MF)) != 0) {
#if IP_REASSEMBLY /* packet fragment reassembly code present? */
LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n",
ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & htons(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8));
/* reassemble the packet*/
p = ip_reass(p);
/* packet not fully reassembled yet? */
if (p == NULL) {
return ERR_OK;
}
iphdr = p->payload;
#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
pbuf_free(p);
LWIP_DEBUGF(IP_DEBUG | 2, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
ntohs(IPH_OFFSET(iphdr))));
IP_STATS_INC(ip.opterr);
IP_STATS_INC(ip.drop);
/* unsupported protocol feature */
snmp_inc_ipinunknownprotos();
return ERR_OK;
#endif /* IP_REASSEMBLY */
}
#if IP_OPTIONS == 0 /* no support for IP options in the IP header? */
if (iphdrlen > IP_HLEN) {
LWIP_DEBUGF(IP_DEBUG | 2, ("IP packet dropped since there were IP options (while IP_OPTIONS == 0).\n"));
pbuf_free(p);
IP_STATS_INC(ip.opterr);
IP_STATS_INC(ip.drop);
/* unsupported protocol feature */
snmp_inc_ipinunknownprotos();
return ERR_OK;
}
#endif /* IP_OPTIONS == 0 */
/* send to upper layers */
LWIP_DEBUGF(IP_DEBUG, ("ip_input: \n"));
ip_debug_print(p);
LWIP_DEBUGF(IP_DEBUG, ("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len));
#if LWIP_RAW
/* raw input did not eat the packet? */
if (raw_input(p, inp) == 0) {
#endif /* LWIP_RAW */
switch (IPH_PROTO(iphdr)) {
#if LWIP_UDP
case IP_PROTO_UDP:
case IP_PROTO_UDPLITE:
snmp_inc_ipindelivers();
udp_input(p, inp);
break;
#endif /* LWIP_UDP */
#if LWIP_TCP
case IP_PROTO_TCP:
snmp_inc_ipindelivers();
tcp_input(p, inp);
break;
#endif /* LWIP_TCP */
case IP_PROTO_ICMP:
snmp_inc_ipindelivers();
icmp_input(p, inp);
break;
default:
/* send ICMP destination protocol unreachable unless is was a broadcast */
if (!ip_addr_isbroadcast(&(iphdr->dest), inp) &&
!ip_addr_ismulticast(&(iphdr->dest))) {
p->payload = iphdr;
icmp_dest_unreach(p, ICMP_DUR_PROTO);
}
pbuf_free(p);
LWIP_DEBUGF(IP_DEBUG | 2, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
IP_STATS_INC(ip.proterr);
IP_STATS_INC(ip.drop);
snmp_inc_ipinunknownprotos();
}
#if LWIP_RAW
} /* LWIP_RAW */
#endif
return ERR_OK;
}
/**
* Sends an IP packet on a network interface. This function constructs
* the IP header and calculates the IP header checksum. If the source
* IP address is NULL, the IP address of the outgoing network
* interface is filled in as source address.
*
* @note ip_id: RFC791 "some host may be able to simply use
* unique identifiers independent of destination"
*/
err_t
ip_output_if(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
u8_t ttl, u8_t tos,
u8_t proto, struct netif *netif)
{
struct ip_hdr *iphdr;
static u16_t ip_id = 0;
snmp_inc_ipoutrequests();
if (dest != IP_HDRINCL) {
if (pbuf_header(p, IP_HLEN)) {
LWIP_DEBUGF(IP_DEBUG | 2, ("ip_output: not enough room for IP header in pbuf\n"));
IP_STATS_INC(ip.err);
snmp_inc_ipoutdiscards();
return ERR_BUF;
}
iphdr = p->payload;
IPH_TTL_SET(iphdr, ttl);
IPH_PROTO_SET(iphdr, proto);
ip_addr_set(&(iphdr->dest), dest);
IPH_VHLTOS_SET(iphdr, 4, IP_HLEN / 4, tos);
IPH_LEN_SET(iphdr, htons(p->tot_len));
IPH_OFFSET_SET(iphdr, htons(IP_DF));
IPH_ID_SET(iphdr, htons(ip_id));
++ip_id;
if (ip_addr_isany(src)) {
ip_addr_set(&(iphdr->src), &(netif->ip_addr));
} else {
ip_addr_set(&(iphdr->src), src);
}
IPH_CHKSUM_SET(iphdr, 0);
#if CHECKSUM_GEN_IP
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
#endif
} else {
iphdr = p->payload;
dest = &(iphdr->dest);
}
#if IP_FRAG
/* don't fragment if interface has mtu set to 0 [loopif] */
if (netif->mtu && (p->tot_len > netif->mtu))
return ip_frag(p,netif,dest);
#endif
IP_STATS_INC(ip.xmit);
LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c%"U16_F"\n", netif->name[0], netif->name[1], netif->num));
ip_debug_print(p);
LWIP_DEBUGF(IP_DEBUG, ("netif->output()"));
return netif->output(netif, p, dest);
}
/**
* Simple interface to ip_output_if. It finds the outgoing network
* interface and calls upon ip_output_if to do the actual work.
*/
err_t
ip_output(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest,
u8_t ttl, u8_t tos, u8_t proto)
{
struct netif *netif;
if ((netif = ip_route(dest)) == NULL) {
LWIP_DEBUGF(IP_DEBUG | 2, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
IP_STATS_INC(ip.rterr);
snmp_inc_ipoutnoroutes();
return ERR_RTE;
}
return ip_output_if(p, src, dest, ttl, tos, proto, netif);
}
#if IP_DEBUG
void
ip_debug_print(struct pbuf *p)
{
struct ip_hdr *iphdr = p->payload;
u8_t *payload;
payload = (u8_t *)iphdr + IP_HLEN;
LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n",
IPH_V(iphdr),
IPH_HL(iphdr),
IPH_TOS(iphdr),
ntohs(IPH_LEN(iphdr))));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("| %5"U16_F" |%"U16_F"%"U16_F"%"U16_F"| %4"U16_F" | (id, flags, offset)\n",
ntohs(IPH_ID(iphdr)),
ntohs(IPH_OFFSET(iphdr)) >> 15 & 1,
ntohs(IPH_OFFSET(iphdr)) >> 14 & 1,
ntohs(IPH_OFFSET(iphdr)) >> 13 & 1,
ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | 0x%04"X16_F" | (ttl, proto, chksum)\n",
IPH_TTL(iphdr),
IPH_PROTO(iphdr),
ntohs(IPH_CHKSUM(iphdr))));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (src)\n",
ip4_addr1(&iphdr->src),
ip4_addr2(&iphdr->src),
ip4_addr3(&iphdr->src),
ip4_addr4(&iphdr->src)));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n",
ip4_addr1(&iphdr->dest),
ip4_addr2(&iphdr->dest),
ip4_addr3(&iphdr->dest),
ip4_addr4(&iphdr->dest)));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
}
#endif /* IP_DEBUG */

78
lwip/core/ipv4/ip_addr.c Normal file
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/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/ip_addr.h"
#include "lwip/inet.h"
#include "lwip/netif.h"
#define IP_ADDR_ANY_VALUE 0x00000000UL
#define IP_ADDR_BROADCAST_VALUE 0xffffffffUL
/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
const struct ip_addr ip_addr_any = { IP_ADDR_ANY_VALUE };
const struct ip_addr ip_addr_broadcast = { IP_ADDR_BROADCAST_VALUE };
/* Determine if an address is a broadcast address on a network interface
*
* @param addr address to be checked
* @param netif the network interface against which the address is checked
* @return returns non-zero if the address is a broadcast address
*
*/
u8_t ip_addr_isbroadcast(struct ip_addr *addr, struct netif *netif)
{
u32_t addr2test;
addr2test = addr->addr;
/* all ones (broadcast) or all zeroes (old skool broadcast) */
if ((~addr2test == IP_ADDR_ANY_VALUE) ||
(addr2test == IP_ADDR_ANY_VALUE))
return 1;
/* no broadcast support on this network interface? */
else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0)
/* the given address cannot be a broadcast address
* nor can we check against any broadcast addresses */
return 0;
/* address matches network interface address exactly? => no broadcast */
else if (addr2test == netif->ip_addr.addr)
return 0;
/* on the same (sub) network... */
else if (ip_addr_netcmp(addr, &(netif->ip_addr), &(netif->netmask))
/* ...and host identifier bits are all ones? =>... */
&& ((addr2test & ~netif->netmask.addr) ==
(IP_ADDR_BROADCAST_VALUE & ~netif->netmask.addr)))
/* => network broadcast address */
return 1;
else
return 0;
}

388
lwip/core/ipv4/ip_frag.c Normal file
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/* @file
*
* This is the IP packet segmentation and reassembly implementation.
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Jani Monoses <jani@iv.ro>
* original reassembly code by Adam Dunkels <adam@sics.se>
*
*/
#include <string.h>
#include "lwip/opt.h"
#include "lwip/ip.h"
#include "lwip/ip_frag.h"
#include "lwip/netif.h"
#include "lwip/snmp.h"
#include "lwip/stats.h"
static u8_t ip_reassbuf[IP_HLEN + IP_REASS_BUFSIZE];
static u8_t ip_reassbitmap[IP_REASS_BUFSIZE / (8 * 8) + 1];
static const u8_t bitmap_bits[8] = { 0xff, 0x7f, 0x3f, 0x1f,
0x0f, 0x07, 0x03, 0x01
};
static u16_t ip_reasslen;
static u8_t ip_reassflags;
#define IP_REASS_FLAG_LASTFRAG 0x01
static u8_t ip_reasstmr;
/*
* Copy len bytes from offset in pbuf to buffer
*
* helper used by both ip_reass and ip_frag
*/
static struct pbuf *
copy_from_pbuf(struct pbuf *p, u16_t * offset,
u8_t * buffer, u16_t len)
{
u16_t l;
p->payload = (u8_t *)p->payload + *offset;
p->len -= *offset;
while (len) {
l = len < p->len ? len : p->len;
memcpy(buffer, p->payload, l);
buffer += l;
len -= l;
if (len)
p = p->next;
else
*offset = l;
}
return p;
}
/**
* Initializes IP reassembly and fragmentation states.
*/
void
ip_frag_init(void)
{
ip_reasstmr = 0;
ip_reassflags = 0;
ip_reasslen = 0;
memset(ip_reassbitmap, 0, sizeof(ip_reassbitmap));
}
/**
* Reassembly timer base function
* for both NO_SYS == 0 and 1 (!).
*
* Should be called every 1000 msec.
*/
void
ip_reass_tmr(void)
{
if (ip_reasstmr > 0) {
ip_reasstmr--;
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer dec %"U16_F"\n",(u16_t)ip_reasstmr));
if (ip_reasstmr == 0) {
/* reassembly timed out */
snmp_inc_ipreasmfails();
}
}
}
/**
* Reassembles incoming IP fragments into an IP datagram.
*
* @param p points to a pbuf chain of the fragment
* @return NULL if reassembly is incomplete, ? otherwise
*/
struct pbuf *
ip_reass(struct pbuf *p)
{
struct pbuf *q;
struct ip_hdr *fraghdr, *iphdr;
u16_t offset, len;
u16_t i;
IPFRAG_STATS_INC(ip_frag.recv);
snmp_inc_ipreasmreqds();
iphdr = (struct ip_hdr *) ip_reassbuf;
fraghdr = (struct ip_hdr *) p->payload;
/* If ip_reasstmr is zero, no packet is present in the buffer, so we
write the IP header of the fragment into the reassembly
buffer. The timer is updated with the maximum age. */
if (ip_reasstmr == 0) {
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass: new packet\n"));
memcpy(iphdr, fraghdr, IP_HLEN);
ip_reasstmr = IP_REASS_MAXAGE;
ip_reassflags = 0;
/* Clear the bitmap. */
memset(ip_reassbitmap, 0, sizeof(ip_reassbitmap));
}
/* Check if the incoming fragment matches the one currently present
in the reasembly buffer. If so, we proceed with copying the
fragment into the buffer. */
if (ip_addr_cmp(&iphdr->src, &fraghdr->src) &&
ip_addr_cmp(&iphdr->dest, &fraghdr->dest) &&
IPH_ID(iphdr) == IPH_ID(fraghdr)) {
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass: matching previous fragment ID=%"X16_F"\n",
ntohs(IPH_ID(fraghdr))));
IPFRAG_STATS_INC(ip_frag.cachehit);
/* Find out the offset in the reassembly buffer where we should
copy the fragment. */
len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
/* If the offset or the offset + fragment length overflows the
reassembly buffer, we discard the entire packet. */
if ((offset > IP_REASS_BUFSIZE) || ((offset + len) > IP_REASS_BUFSIZE)) {
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: fragment outside of buffer (%"S16_F":%"S16_F"/%"S16_F").\n", offset,
offset + len, IP_REASS_BUFSIZE));
ip_reasstmr = 0;
snmp_inc_ipreasmfails();
goto nullreturn;
}
/* Copy the fragment into the reassembly buffer, at the right
offset. */
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: copying with offset %"S16_F" into %"S16_F":%"S16_F"\n", offset,
IP_HLEN + offset, IP_HLEN + offset + len));
i = IPH_HL(fraghdr) * 4;
copy_from_pbuf(p, &i, &ip_reassbuf[IP_HLEN + offset], len);
/* Update the bitmap. */
if (offset / (8 * 8) == (offset + len) / (8 * 8)) {
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: updating single byte in bitmap.\n"));
/* If the two endpoints are in the same byte, we only update that byte. */
LWIP_ASSERT("offset / (8 * 8) < sizeof(ip_reassbitmap)",
offset / (8 * 8) < sizeof(ip_reassbitmap));
ip_reassbitmap[offset / (8 * 8)] |=
bitmap_bits[(offset / 8) & 7] &
~bitmap_bits[((offset + len) / 8) & 7];
} else {
/* If the two endpoints are in different bytes, we update the
bytes in the endpoints and fill the stuff inbetween with
0xff. */
LWIP_ASSERT("offset / (8 * 8) < sizeof(ip_reassbitmap)",
offset / (8 * 8) < sizeof(ip_reassbitmap));
ip_reassbitmap[offset / (8 * 8)] |= bitmap_bits[(offset / 8) & 7];
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: updating many bytes in bitmap (%"S16_F":%"S16_F").\n",
1 + offset / (8 * 8), (offset + len) / (8 * 8)));
for (i = 1 + offset / (8 * 8); i < (offset + len) / (8 * 8); ++i) {
ip_reassbitmap[i] = 0xff;
}
LWIP_ASSERT("(offset + len) / (8 * 8) < sizeof(ip_reassbitmap)",
(offset + len) / (8 * 8) < sizeof(ip_reassbitmap));
ip_reassbitmap[(offset + len) / (8 * 8)] |=
~bitmap_bits[((offset + len) / 8) & 7];
}
/* If this fragment has the More Fragments flag set to zero, we
know that this is the last fragment, so we can calculate the
size of the entire packet. We also set the
IP_REASS_FLAG_LASTFRAG flag to indicate that we have received
the final fragment. */
if ((ntohs(IPH_OFFSET(fraghdr)) & IP_MF) == 0) {
ip_reassflags |= IP_REASS_FLAG_LASTFRAG;
ip_reasslen = offset + len;
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: last fragment seen, total len %"S16_F"\n",
ip_reasslen));
}
/* Finally, we check if we have a full packet in the buffer. We do
this by checking if we have the last fragment and if all bits
in the bitmap are set. */
if (ip_reassflags & IP_REASS_FLAG_LASTFRAG) {
/* Check all bytes up to and including all but the last byte in
the bitmap. */
LWIP_ASSERT("ip_reasslen / (8 * 8) - 1 < sizeof(ip_reassbitmap)",
ip_reasslen / (8 * 8) - 1 < ((u16_t) sizeof(ip_reassbitmap)));
for (i = 0; i < ip_reasslen / (8 * 8) - 1; ++i) {
if (ip_reassbitmap[i] != 0xff) {
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: last fragment seen, bitmap %"S16_F"/%"S16_F" failed (%"X16_F")\n",
i, ip_reasslen / (8 * 8) - 1, ip_reassbitmap[i]));
goto nullreturn;
}
}
/* Check the last byte in the bitmap. It should contain just the
right amount of bits. */
LWIP_ASSERT("ip_reasslen / (8 * 8) < sizeof(ip_reassbitmap)",
ip_reasslen / (8 * 8) < sizeof(ip_reassbitmap));
if (ip_reassbitmap[ip_reasslen / (8 * 8)] !=
(u8_t) ~ bitmap_bits[ip_reasslen / 8 & 7]) {
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: last fragment seen, bitmap %"S16_F" didn't contain %"X16_F" (%"X16_F")\n",
ip_reasslen / (8 * 8), ~bitmap_bits[ip_reasslen / 8 & 7],
ip_reassbitmap[ip_reasslen / (8 * 8)]));
goto nullreturn;
}
/* Pretend to be a "normal" (i.e., not fragmented) IP packet
from now on. */
ip_reasslen += IP_HLEN;
IPH_LEN_SET(iphdr, htons(ip_reasslen));
IPH_OFFSET_SET(iphdr, 0);
IPH_CHKSUM_SET(iphdr, 0);
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
/* If we have come this far, we have a full packet in the
buffer, so we allocate a pbuf and copy the packet into it. We
also reset the timer. */
ip_reasstmr = 0;
pbuf_free(p);
p = pbuf_alloc(PBUF_LINK, ip_reasslen, PBUF_POOL);
if (p != NULL) {
i = 0;
for (q = p; q != NULL; q = q->next) {
/* Copy enough bytes to fill this pbuf in the chain. The
available data in the pbuf is given by the q->len variable. */
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: memcpy from %p (%"S16_F") to %p, %"S16_F" bytes\n",
(void *)&ip_reassbuf[i], i, q->payload,
q->len > ip_reasslen - i ? ip_reasslen - i : q->len));
memcpy(q->payload, &ip_reassbuf[i],
q->len > ip_reasslen - i ? ip_reasslen - i : q->len);
i += q->len;
}
IPFRAG_STATS_INC(ip_frag.fw);
snmp_inc_ipreasmoks();
} else {
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: pbuf_alloc(PBUF_LINK, ip_reasslen=%"U16_F", PBUF_POOL) failed\n", ip_reasslen));
IPFRAG_STATS_INC(ip_frag.memerr);
snmp_inc_ipreasmfails();
}
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass: p %p\n", (void*)p));
return p;
}
}
nullreturn:
IPFRAG_STATS_INC(ip_frag.drop);
pbuf_free(p);
return NULL;
}
static u8_t buf[MEM_ALIGN_SIZE(IP_FRAG_MAX_MTU)];
/**
* Fragment an IP datagram if too large for the netif.
*
* Chop the datagram in MTU sized chunks and send them in order
* by using a fixed size static memory buffer (PBUF_ROM)
*/
err_t
ip_frag(struct pbuf *p, struct netif *netif, struct ip_addr *dest)
{
struct pbuf *rambuf;
struct pbuf *header;
struct ip_hdr *iphdr;
u16_t nfb = 0;
u16_t left, cop;
u16_t mtu = netif->mtu;
u16_t ofo, omf;
u16_t last;
u16_t poff = IP_HLEN;
u16_t tmp;
/* Get a RAM based MTU sized pbuf */
rambuf = pbuf_alloc(PBUF_LINK, 0, PBUF_REF);
if (rambuf == NULL) {
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc(PBUF_LINK, 0, PBUF_REF) failed\n"));
return ERR_MEM;
}
rambuf->tot_len = rambuf->len = mtu;
rambuf->payload = MEM_ALIGN((void *)buf);
/* Copy the IP header in it */
iphdr = rambuf->payload;
memcpy(iphdr, p->payload, IP_HLEN);
/* Save original offset */
tmp = ntohs(IPH_OFFSET(iphdr));
ofo = tmp & IP_OFFMASK;
omf = tmp & IP_MF;
left = p->tot_len - IP_HLEN;
while (left) {
last = (left <= mtu - IP_HLEN);
/* Set new offset and MF flag */
ofo += nfb;
tmp = omf | (IP_OFFMASK & (ofo));
if (!last)
tmp = tmp | IP_MF;
IPH_OFFSET_SET(iphdr, htons(tmp));
/* Fill this fragment */
nfb = (mtu - IP_HLEN) / 8;
cop = last ? left : nfb * 8;
p = copy_from_pbuf(p, &poff, (u8_t *) iphdr + IP_HLEN, cop);
/* Correct header */
IPH_LEN_SET(iphdr, htons(cop + IP_HLEN));
IPH_CHKSUM_SET(iphdr, 0);
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
if (last)
pbuf_realloc(rambuf, left + IP_HLEN);
/* This part is ugly: we alloc a RAM based pbuf for
* the link level header for each chunk and then
* free it.A PBUF_ROM style pbuf for which pbuf_header
* worked would make things simpler.
*/
header = pbuf_alloc(PBUF_LINK, 0, PBUF_RAM);
if (header != NULL) {
pbuf_chain(header, rambuf);
netif->output(netif, header, dest);
IPFRAG_STATS_INC(ip_frag.xmit);
snmp_inc_ipfragcreates();
pbuf_free(header);
} else {
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_frag: pbuf_alloc() for header failed\n"));
pbuf_free(rambuf);
return ERR_MEM;
}
left -= cop;
}
pbuf_free(rambuf);
snmp_inc_ipfragoks();
return ERR_OK;
}