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This commit is contained in:
Joseph Henry
2016-06-14 16:01:19 -07:00
parent 76b7e0fef7
commit c1ce7dc87a
436 changed files with 87247 additions and 473 deletions
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528
ext/lwip/src/core/ipv4/autoip.c Normal file
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/**
* @file
* AutoIP Automatic LinkLocal IP Configuration
*
*/
/*
*
* Copyright (c) 2007 Dominik Spies <kontakt@dspies.de>
* 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.
*
* Author: Dominik Spies <kontakt@dspies.de>
*
* This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform
* with RFC 3927.
*
*
* Please coordinate changes and requests with Dominik Spies
* <kontakt@dspies.de>
*/
/*******************************************************************************
* USAGE:
*
* define LWIP_AUTOIP 1 in your lwipopts.h
*
* If you don't use tcpip.c (so, don't call, you don't call tcpip_init):
* - First, call autoip_init().
* - call autoip_tmr() all AUTOIP_TMR_INTERVAL msces,
* that should be defined in autoip.h.
* I recommend a value of 100. The value must divide 1000 with a remainder almost 0.
* Possible values are 1000, 500, 333, 250, 200, 166, 142, 125, 111, 100 ....
*
* Without DHCP:
* - Call autoip_start() after netif_add().
*
* With DHCP:
* - define LWIP_DHCP_AUTOIP_COOP 1 in your lwipopts.h.
* - Configure your DHCP Client.
*
*/
#include "lwip/opt.h"
#if LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */
#include "lwip/mem.h"
#include "lwip/udp.h"
#include "lwip/ip_addr.h"
#include "lwip/netif.h"
#include "lwip/autoip.h"
#include "netif/etharp.h"
#include <stdlib.h>
#include <string.h>
/* 169.254.0.0 */
#define AUTOIP_NET 0xA9FE0000
/* 169.254.1.0 */
#define AUTOIP_RANGE_START (AUTOIP_NET | 0x0100)
/* 169.254.254.255 */
#define AUTOIP_RANGE_END (AUTOIP_NET | 0xFEFF)
/** Pseudo random macro based on netif informations.
* You could use "rand()" from the C Library if you define LWIP_AUTOIP_RAND in lwipopts.h */
#ifndef LWIP_AUTOIP_RAND
#define LWIP_AUTOIP_RAND(netif) ( (((u32_t)((netif->hwaddr[5]) & 0xff) << 24) | \
((u32_t)((netif->hwaddr[3]) & 0xff) << 16) | \
((u32_t)((netif->hwaddr[2]) & 0xff) << 8) | \
((u32_t)((netif->hwaddr[4]) & 0xff))) + \
(netif->autoip?netif->autoip->tried_llipaddr:0))
#endif /* LWIP_AUTOIP_RAND */
/**
* Macro that generates the initial IP address to be tried by AUTOIP.
* If you want to override this, define it to something else in lwipopts.h.
*/
#ifndef LWIP_AUTOIP_CREATE_SEED_ADDR
#define LWIP_AUTOIP_CREATE_SEED_ADDR(netif) \
htonl(AUTOIP_RANGE_START + ((u32_t)(((u8_t)(netif->hwaddr[4])) | \
((u32_t)((u8_t)(netif->hwaddr[5]))) << 8)))
#endif /* LWIP_AUTOIP_CREATE_SEED_ADDR */
/* static functions */
static void autoip_handle_arp_conflict(struct netif *netif);
/* creates a pseudo random LL IP-Address for a network interface */
static void autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr);
/* sends an ARP probe */
static err_t autoip_arp_probe(struct netif *netif);
/* sends an ARP announce */
static err_t autoip_arp_announce(struct netif *netif);
/* configure interface for use with current LL IP-Address */
static err_t autoip_bind(struct netif *netif);
/* start sending probes for llipaddr */
static void autoip_start_probing(struct netif *netif);
/** Set a statically allocated struct autoip to work with.
* Using this prevents autoip_start to allocate it using mem_malloc.
*
* @param netif the netif for which to set the struct autoip
* @param dhcp (uninitialised) dhcp struct allocated by the application
*/
void
autoip_set_struct(struct netif *netif, struct autoip *autoip)
{
LWIP_ASSERT("netif != NULL", netif != NULL);
LWIP_ASSERT("autoip != NULL", autoip != NULL);
LWIP_ASSERT("netif already has a struct autoip set", netif->autoip == NULL);
/* clear data structure */
memset(autoip, 0, sizeof(struct autoip));
/* autoip->state = AUTOIP_STATE_OFF; */
netif->autoip = autoip;
}
/** Restart AutoIP client and check the next address (conflict detected)
*
* @param netif The netif under AutoIP control
*/
static void
autoip_restart(struct netif *netif)
{
netif->autoip->tried_llipaddr++;
autoip_start(netif);
}
/**
* Handle a IP address conflict after an ARP conflict detection
*/
static void
autoip_handle_arp_conflict(struct netif *netif)
{
/* Somehow detect if we are defending or retreating */
unsigned char defend = 1; /* tbd */
if (defend) {
if (netif->autoip->lastconflict > 0) {
/* retreat, there was a conflicting ARP in the last
* DEFEND_INTERVAL seconds
*/
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_handle_arp_conflict(): we are defending, but in DEFEND_INTERVAL, retreating\n"));
/* TODO: close all TCP sessions */
autoip_restart(netif);
} else {
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_handle_arp_conflict(): we are defend, send ARP Announce\n"));
autoip_arp_announce(netif);
netif->autoip->lastconflict = DEFEND_INTERVAL * AUTOIP_TICKS_PER_SECOND;
}
} else {
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_handle_arp_conflict(): we do not defend, retreating\n"));
/* TODO: close all TCP sessions */
autoip_restart(netif);
}
}
/**
* Create an IP-Address out of range 169.254.1.0 to 169.254.254.255
*
* @param netif network interface on which create the IP-Address
* @param ipaddr ip address to initialize
*/
static void
autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr)
{
/* Here we create an IP-Address out of range 169.254.1.0 to 169.254.254.255
* compliant to RFC 3927 Section 2.1
* We have 254 * 256 possibilities */
u32_t addr = ntohl(LWIP_AUTOIP_CREATE_SEED_ADDR(netif));
addr += netif->autoip->tried_llipaddr;
addr = AUTOIP_NET | (addr & 0xffff);
/* Now, 169.254.0.0 <= addr <= 169.254.255.255 */
if (addr < AUTOIP_RANGE_START) {
addr += AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1;
}
if (addr > AUTOIP_RANGE_END) {
addr -= AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1;
}
LWIP_ASSERT("AUTOIP address not in range", (addr >= AUTOIP_RANGE_START) &&
(addr <= AUTOIP_RANGE_END));
ip4_addr_set_u32(ipaddr, htonl(addr));
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_create_addr(): tried_llipaddr=%"U16_F", %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
(u16_t)(netif->autoip->tried_llipaddr), ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr),
ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
}
/**
* Sends an ARP probe from a network interface
*
* @param netif network interface used to send the probe
*/
static err_t
autoip_arp_probe(struct netif *netif)
{
return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
(struct eth_addr *)netif->hwaddr, IP_ADDR_ANY, &ethzero,
&netif->autoip->llipaddr, ARP_REQUEST);
}
/**
* Sends an ARP announce from a network interface
*
* @param netif network interface used to send the announce
*/
static err_t
autoip_arp_announce(struct netif *netif)
{
return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
(struct eth_addr *)netif->hwaddr, &netif->autoip->llipaddr, &ethzero,
&netif->autoip->llipaddr, ARP_REQUEST);
}
/**
* Configure interface for use with current LL IP-Address
*
* @param netif network interface to configure with current LL IP-Address
*/
static err_t
autoip_bind(struct netif *netif)
{
struct autoip *autoip = netif->autoip;
ip_addr_t sn_mask, gw_addr;
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_bind(netif=%p) %c%c%"U16_F" %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
(void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num,
ip4_addr1_16(&autoip->llipaddr), ip4_addr2_16(&autoip->llipaddr),
ip4_addr3_16(&autoip->llipaddr), ip4_addr4_16(&autoip->llipaddr)));
IP4_ADDR(&sn_mask, 255, 255, 0, 0);
IP4_ADDR(&gw_addr, 0, 0, 0, 0);
netif_set_ipaddr(netif, &autoip->llipaddr);
netif_set_netmask(netif, &sn_mask);
netif_set_gw(netif, &gw_addr);
/* bring the interface up */
netif_set_up(netif);
return ERR_OK;
}
/**
* Start AutoIP client
*
* @param netif network interface on which start the AutoIP client
*/
err_t
autoip_start(struct netif *netif)
{
struct autoip *autoip = netif->autoip;
err_t result = ERR_OK;
if (netif_is_up(netif)) {
netif_set_down(netif);
}
/* Set IP-Address, Netmask and Gateway to 0 to make sure that
* ARP Packets are formed correctly
*/
ip_addr_set_zero(&netif->ip_addr);
ip_addr_set_zero(&netif->netmask);
ip_addr_set_zero(&netif->gw);
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_start(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0],
netif->name[1], (u16_t)netif->num));
if (autoip == NULL) {
/* no AutoIP client attached yet? */
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_start(): starting new AUTOIP client\n"));
autoip = (struct autoip *)mem_malloc(sizeof(struct autoip));
if (autoip == NULL) {
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_start(): could not allocate autoip\n"));
return ERR_MEM;
}
memset(autoip, 0, sizeof(struct autoip));
/* store this AutoIP client in the netif */
netif->autoip = autoip;
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_start(): allocated autoip"));
} else {
autoip->state = AUTOIP_STATE_OFF;
autoip->ttw = 0;
autoip->sent_num = 0;
ip_addr_set_zero(&autoip->llipaddr);
autoip->lastconflict = 0;
}
autoip_create_addr(netif, &(autoip->llipaddr));
autoip_start_probing(netif);
return result;
}
static void
autoip_start_probing(struct netif *netif)
{
struct autoip *autoip = netif->autoip;
autoip->state = AUTOIP_STATE_PROBING;
autoip->sent_num = 0;
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_start_probing(): changing state to PROBING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
/* time to wait to first probe, this is randomly
* choosen out of 0 to PROBE_WAIT seconds.
* compliant to RFC 3927 Section 2.2.1
*/
autoip->ttw = (u16_t)(LWIP_AUTOIP_RAND(netif) % (PROBE_WAIT * AUTOIP_TICKS_PER_SECOND));
/*
* if we tried more then MAX_CONFLICTS we must limit our rate for
* accquiring and probing address
* compliant to RFC 3927 Section 2.2.1
*/
if (autoip->tried_llipaddr > MAX_CONFLICTS) {
autoip->ttw = RATE_LIMIT_INTERVAL * AUTOIP_TICKS_PER_SECOND;
}
}
/**
* Handle a possible change in the network configuration.
*
* If there is an AutoIP address configured, take the interface down
* and begin probing with the same address.
*/
void
autoip_network_changed(struct netif *netif)
{
if (netif->autoip && netif->autoip->state != AUTOIP_STATE_OFF) {
netif_set_down(netif);
autoip_start_probing(netif);
}
}
/**
* Stop AutoIP client
*
* @param netif network interface on which stop the AutoIP client
*/
err_t
autoip_stop(struct netif *netif)
{
netif->autoip->state = AUTOIP_STATE_OFF;
netif_set_down(netif);
return ERR_OK;
}
/**
* Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds
*/
void
autoip_tmr()
{
struct netif *netif = netif_list;
/* loop through netif's */
while (netif != NULL) {
/* only act on AutoIP configured interfaces */
if (netif->autoip != NULL) {
if (netif->autoip->lastconflict > 0) {
netif->autoip->lastconflict--;
}
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_tmr() AutoIP-State: %"U16_F", ttw=%"U16_F"\n",
(u16_t)(netif->autoip->state), netif->autoip->ttw));
switch(netif->autoip->state) {
case AUTOIP_STATE_PROBING:
if (netif->autoip->ttw > 0) {
netif->autoip->ttw--;
} else {
if (netif->autoip->sent_num >= PROBE_NUM) {
netif->autoip->state = AUTOIP_STATE_ANNOUNCING;
netif->autoip->sent_num = 0;
netif->autoip->ttw = ANNOUNCE_WAIT * AUTOIP_TICKS_PER_SECOND;
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_tmr(): changing state to ANNOUNCING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
} else {
autoip_arp_probe(netif);
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_tmr() PROBING Sent Probe\n"));
netif->autoip->sent_num++;
/* calculate time to wait to next probe */
netif->autoip->ttw = (u16_t)((LWIP_AUTOIP_RAND(netif) %
((PROBE_MAX - PROBE_MIN) * AUTOIP_TICKS_PER_SECOND) ) +
PROBE_MIN * AUTOIP_TICKS_PER_SECOND);
}
}
break;
case AUTOIP_STATE_ANNOUNCING:
if (netif->autoip->ttw > 0) {
netif->autoip->ttw--;
} else {
if (netif->autoip->sent_num == 0) {
/* We are here the first time, so we waited ANNOUNCE_WAIT seconds
* Now we can bind to an IP address and use it.
*
* autoip_bind calls netif_set_up. This triggers a gratuitous ARP
* which counts as an announcement.
*/
autoip_bind(netif);
} else {
autoip_arp_announce(netif);
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE,
("autoip_tmr() ANNOUNCING Sent Announce\n"));
}
netif->autoip->ttw = ANNOUNCE_INTERVAL * AUTOIP_TICKS_PER_SECOND;
netif->autoip->sent_num++;
if (netif->autoip->sent_num >= ANNOUNCE_NUM) {
netif->autoip->state = AUTOIP_STATE_BOUND;
netif->autoip->sent_num = 0;
netif->autoip->ttw = 0;
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE,
("autoip_tmr(): changing state to BOUND: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr),
ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr)));
}
}
break;
}
}
/* proceed to next network interface */
netif = netif->next;
}
}
/**
* Handles every incoming ARP Packet, called by etharp_arp_input.
*
* @param netif network interface to use for autoip processing
* @param hdr Incoming ARP packet
*/
void
autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr)
{
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_arp_reply()\n"));
if ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) {
/* when ip.src == llipaddr && hw.src != netif->hwaddr
*
* when probing ip.dst == llipaddr && hw.src != netif->hwaddr
* we have a conflict and must solve it
*/
ip_addr_t sipaddr, dipaddr;
struct eth_addr netifaddr;
ETHADDR16_COPY(netifaddr.addr, netif->hwaddr);
/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
* structure packing (not using structure copy which breaks strict-aliasing rules).
*/
IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
if ((netif->autoip->state == AUTOIP_STATE_PROBING) ||
((netif->autoip->state == AUTOIP_STATE_ANNOUNCING) &&
(netif->autoip->sent_num == 0))) {
/* RFC 3927 Section 2.2.1:
* from beginning to after ANNOUNCE_WAIT
* seconds we have a conflict if
* ip.src == llipaddr OR
* ip.dst == llipaddr && hw.src != own hwaddr
*/
if ((ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr)) ||
(ip_addr_cmp(&dipaddr, &netif->autoip->llipaddr) &&
!eth_addr_cmp(&netifaddr, &hdr->shwaddr))) {
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING,
("autoip_arp_reply(): Probe Conflict detected\n"));
autoip_restart(netif);
}
} else {
/* RFC 3927 Section 2.5:
* in any state we have a conflict if
* ip.src == llipaddr && hw.src != own hwaddr
*/
if (ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr) &&
!eth_addr_cmp(&netifaddr, &hdr->shwaddr)) {
LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING,
("autoip_arp_reply(): Conflicting ARP-Packet detected\n"));
autoip_handle_arp_conflict(netif);
}
}
}
}
#endif /* LWIP_AUTOIP */

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ext/lwip/src/core/ipv4/icmp.c Normal file
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/**
* @file
* ICMP - Internet Control Message Protocol
*
*/
/*
* 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 "lwip/opt.h"
#if LWIP_ICMP /* don't build if not configured for use in lwipopts.h */
#include "lwip/icmp.h"
#include "lwip/inet_chksum.h"
#include "lwip/ip.h"
#include "lwip/def.h"
#include "lwip/stats.h"
#include "lwip/snmp.h"
#include <string.h>
/** Small optimization: set to 0 if incoming PBUF_POOL pbuf always can be
* used to modify and send a response packet (and to 1 if this is not the case,
* e.g. when link header is stripped of when receiving) */
#ifndef LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
#define LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN 1
#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
/* The amount of data from the original packet to return in a dest-unreachable */
#define ICMP_DEST_UNREACH_DATASIZE 8
static void icmp_send_response(struct pbuf *p, u8_t type, u8_t code);
/**
* Processes ICMP input packets, called from ip_input().
*
* Currently only processes icmp echo requests and sends
* out the echo response.
*
* @param p the icmp echo request packet, p->payload pointing to the ip header
* @param inp the netif on which this packet was received
*/
void
icmp_input(struct pbuf *p, struct netif *inp)
{
u8_t type;
#ifdef LWIP_DEBUG
u8_t code;
#endif /* LWIP_DEBUG */
struct icmp_echo_hdr *iecho;
struct ip_hdr *iphdr;
s16_t hlen;
ICMP_STATS_INC(icmp.recv);
snmp_inc_icmpinmsgs();
iphdr = (struct ip_hdr *)p->payload;
hlen = IPH_HL(iphdr) * 4;
if (pbuf_header(p, -hlen) || (p->tot_len < sizeof(u16_t)*2)) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: short ICMP (%"U16_F" bytes) received\n", p->tot_len));
goto lenerr;
}
type = *((u8_t *)p->payload);
#ifdef LWIP_DEBUG
code = *(((u8_t *)p->payload)+1);
#endif /* LWIP_DEBUG */
switch (type) {
case ICMP_ER:
/* This is OK, echo reply might have been parsed by a raw PCB
(as obviously, an echo request has been sent, too). */
break;
case ICMP_ECHO:
#if !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING
{
int accepted = 1;
#if !LWIP_MULTICAST_PING
/* multicast destination address? */
if (ip_addr_ismulticast(&current_iphdr_dest)) {
accepted = 0;
}
#endif /* LWIP_MULTICAST_PING */
#if !LWIP_BROADCAST_PING
/* broadcast destination address? */
if (ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
accepted = 0;
}
#endif /* LWIP_BROADCAST_PING */
/* broadcast or multicast destination address not acceptd? */
if (!accepted) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: Not echoing to multicast or broadcast pings\n"));
ICMP_STATS_INC(icmp.err);
pbuf_free(p);
return;
}
}
#endif /* !LWIP_MULTICAST_PING || !LWIP_BROADCAST_PING */
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"));
goto lenerr;
}
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;
}
#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
if (pbuf_header(p, (PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
/* p is not big enough to contain link headers
* allocate a new one and copy p into it
*/
struct pbuf *r;
/* switch p->payload to ip header */
if (pbuf_header(p, hlen)) {
LWIP_ASSERT("icmp_input: moving p->payload to ip header failed\n", 0);
goto memerr;
}
/* allocate new packet buffer with space for link headers */
r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM);
if (r == NULL) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: allocating new pbuf failed\n"));
goto memerr;
}
LWIP_ASSERT("check that first pbuf can hold struct the ICMP header",
(r->len >= hlen + sizeof(struct icmp_echo_hdr)));
/* copy the whole packet including ip header */
if (pbuf_copy(r, p) != ERR_OK) {
LWIP_ASSERT("icmp_input: copying to new pbuf failed\n", 0);
goto memerr;
}
iphdr = (struct ip_hdr *)r->payload;
/* switch r->payload back to icmp header */
if (pbuf_header(r, -hlen)) {
LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
goto memerr;
}
/* free the original p */
pbuf_free(p);
/* we now have an identical copy of p that has room for link headers */
p = r;
} else {
/* restore p->payload to point to icmp header */
if (pbuf_header(p, -(s16_t)(PBUF_IP_HLEN + PBUF_LINK_HLEN))) {
LWIP_ASSERT("icmp_input: restoring original p->payload failed\n", 0);
goto memerr;
}
}
#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
/* At this point, all checks are OK. */
/* We generate an answer by switching the dest and src ip addresses,
* setting the icmp type to ECHO_RESPONSE and updating the checksum. */
iecho = (struct icmp_echo_hdr *)p->payload;
ip_addr_copy(iphdr->src, *ip_current_dest_addr());
ip_addr_copy(iphdr->dest, *ip_current_src_addr());
ICMPH_TYPE_SET(iecho, ICMP_ER);
#if CHECKSUM_GEN_ICMP
/* adjust the checksum */
if (iecho->chksum >= PP_HTONS(0xffffU - (ICMP_ECHO << 8))) {
iecho->chksum += PP_HTONS(ICMP_ECHO << 8) + 1;
} else {
iecho->chksum += PP_HTONS(ICMP_ECHO << 8);
}
#else /* CHECKSUM_GEN_ICMP */
iecho->chksum = 0;
#endif /* CHECKSUM_GEN_ICMP */
/* Set the correct TTL and recalculate the header checksum. */
IPH_TTL_SET(iphdr, ICMP_TTL);
IPH_CHKSUM_SET(iphdr, 0);
#if CHECKSUM_GEN_IP
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
#endif /* CHECKSUM_GEN_IP */
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();
if(pbuf_header(p, hlen)) {
LWIP_ASSERT("Can't move over header in packet", 0);
} else {
err_t ret;
/* send an ICMP packet, src addr is the dest addr of the curren packet */
ret = ip_output_if(p, ip_current_dest_addr(), IP_HDRINCL,
ICMP_TTL, 0, IP_PROTO_ICMP, inp);
if (ret != ERR_OK) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_input: ip_output_if returned an error: %c.\n", ret));
}
}
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);
return;
lenerr:
pbuf_free(p);
ICMP_STATS_INC(icmp.lenerr);
snmp_inc_icmpinerrors();
return;
#if LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN
memerr:
pbuf_free(p);
ICMP_STATS_INC(icmp.err);
snmp_inc_icmpinerrors();
return;
#endif /* LWIP_ICMP_ECHO_CHECK_INPUT_PBUF_LEN */
}
/**
* Send an icmp 'destination unreachable' packet, called from ip_input() if
* the transport layer protocol is unknown and from udp_input() if the local
* port is not bound.
*
* @param p the input packet for which the 'unreachable' should be sent,
* p->payload pointing to the IP header
* @param t type of the 'unreachable' packet
*/
void
icmp_dest_unreach(struct pbuf *p, enum icmp_dur_type t)
{
icmp_send_response(p, ICMP_DUR, t);
}
#if IP_FORWARD || IP_REASSEMBLY
/**
* Send a 'time exceeded' packet, called from ip_forward() if TTL is 0.
*
* @param p the input packet for which the 'time exceeded' should be sent,
* p->payload pointing to the IP header
* @param t type of the 'time exceeded' packet
*/
void
icmp_time_exceeded(struct pbuf *p, enum icmp_te_type t)
{
icmp_send_response(p, ICMP_TE, t);
}
#endif /* IP_FORWARD || IP_REASSEMBLY */
/**
* Send an icmp packet in response to an incoming packet.
*
* @param p the input packet for which the 'unreachable' should be sent,
* p->payload pointing to the IP header
* @param type Type of the ICMP header
* @param code Code of the ICMP header
*/
static void
icmp_send_response(struct pbuf *p, u8_t type, u8_t code)
{
struct pbuf *q;
struct ip_hdr *iphdr;
/* we can use the echo header here */
struct icmp_echo_hdr *icmphdr;
ip_addr_t iphdr_src;
/* ICMP header + IP header + 8 bytes of data */
q = pbuf_alloc(PBUF_IP, sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE,
PBUF_RAM);
if (q == NULL) {
LWIP_DEBUGF(ICMP_DEBUG, ("icmp_time_exceeded: failed to allocate pbuf for ICMP packet.\n"));
return;
}
LWIP_ASSERT("check that first pbuf can hold icmp message",
(q->len >= (sizeof(struct icmp_echo_hdr) + IP_HLEN + ICMP_DEST_UNREACH_DATASIZE)));
iphdr = (struct ip_hdr *)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"));
icmphdr = (struct icmp_echo_hdr *)q->payload;
icmphdr->type = type;
icmphdr->code = code;
icmphdr->id = 0;
icmphdr->seqno = 0;
/* copy fields from original packet */
SMEMCPY((u8_t *)q->payload + sizeof(struct icmp_echo_hdr), (u8_t *)p->payload,
IP_HLEN + ICMP_DEST_UNREACH_DATASIZE);
/* calculate checksum */
icmphdr->chksum = 0;
icmphdr->chksum = inet_chksum(icmphdr, 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_addr_copy(iphdr_src, iphdr->src);
ip_output(q, NULL, &iphdr_src, ICMP_TTL, 0, IP_PROTO_ICMP);
pbuf_free(q);
}
#endif /* LWIP_ICMP */

805
ext/lwip/src/core/ipv4/igmp.c Normal file
View File

@@ -0,0 +1,805 @@
/**
* @file
* IGMP - Internet Group Management Protocol
*
*/
/*
* Copyright (c) 2002 CITEL Technologies Ltd.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is a contribution to the lwIP TCP/IP stack.
* The Swedish Institute of Computer Science and Adam Dunkels
* are specifically granted permission to redistribute this
* source code.
*/
/*-------------------------------------------------------------
Note 1)
Although the rfc requires V1 AND V2 capability
we will only support v2 since now V1 is very old (August 1989)
V1 can be added if required
a debug print and statistic have been implemented to
show this up.
-------------------------------------------------------------
-------------------------------------------------------------
Note 2)
A query for a specific group address (as opposed to ALLHOSTS)
has now been implemented as I am unsure if it is required
a debug print and statistic have been implemented to
show this up.
-------------------------------------------------------------
-------------------------------------------------------------
Note 3)
The router alert rfc 2113 is implemented in outgoing packets
but not checked rigorously incoming
-------------------------------------------------------------
Steve Reynolds
------------------------------------------------------------*/
/*-----------------------------------------------------------------------------
* RFC 988 - Host extensions for IP multicasting - V0
* RFC 1054 - Host extensions for IP multicasting -
* RFC 1112 - Host extensions for IP multicasting - V1
* RFC 2236 - Internet Group Management Protocol, Version 2 - V2 <- this code is based on this RFC (it's the "de facto" standard)
* RFC 3376 - Internet Group Management Protocol, Version 3 - V3
* RFC 4604 - Using Internet Group Management Protocol Version 3... - V3+
* RFC 2113 - IP Router Alert Option -
*----------------------------------------------------------------------------*/
/*-----------------------------------------------------------------------------
* Includes
*----------------------------------------------------------------------------*/
#include "lwip/opt.h"
#if LWIP_IGMP /* don't build if not configured for use in lwipopts.h */
#include "lwip/igmp.h"
#include "lwip/debug.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/ip.h"
#include "lwip/inet_chksum.h"
#include "lwip/netif.h"
#include "lwip/icmp.h"
#include "lwip/udp.h"
#include "lwip/tcp.h"
#include "lwip/stats.h"
#include "string.h"
/*
* IGMP constants
*/
#define IGMP_TTL 1
#define IGMP_MINLEN 8
#define ROUTER_ALERT 0x9404U
#define ROUTER_ALERTLEN 4
/*
* IGMP message types, including version number.
*/
#define IGMP_MEMB_QUERY 0x11 /* Membership query */
#define IGMP_V1_MEMB_REPORT 0x12 /* Ver. 1 membership report */
#define IGMP_V2_MEMB_REPORT 0x16 /* Ver. 2 membership report */
#define IGMP_LEAVE_GROUP 0x17 /* Leave-group message */
/* Group membership states */
#define IGMP_GROUP_NON_MEMBER 0
#define IGMP_GROUP_DELAYING_MEMBER 1
#define IGMP_GROUP_IDLE_MEMBER 2
/**
* IGMP packet format.
*/
#ifdef PACK_STRUCT_USE_INCLUDES
# include "arch/bpstruct.h"
#endif
PACK_STRUCT_BEGIN
struct igmp_msg {
PACK_STRUCT_FIELD(u8_t igmp_msgtype);
PACK_STRUCT_FIELD(u8_t igmp_maxresp);
PACK_STRUCT_FIELD(u16_t igmp_checksum);
PACK_STRUCT_FIELD(ip_addr_p_t igmp_group_address);
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END
#ifdef PACK_STRUCT_USE_INCLUDES
# include "arch/epstruct.h"
#endif
static struct igmp_group *igmp_lookup_group(struct netif *ifp, ip_addr_t *addr);
static err_t igmp_remove_group(struct igmp_group *group);
static void igmp_timeout( struct igmp_group *group);
static void igmp_start_timer(struct igmp_group *group, u8_t max_time);
static void igmp_delaying_member(struct igmp_group *group, u8_t maxresp);
static err_t igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif);
static void igmp_send(struct igmp_group *group, u8_t type);
static struct igmp_group* igmp_group_list;
static ip_addr_t allsystems;
static ip_addr_t allrouters;
/**
* Initialize the IGMP module
*/
void
igmp_init(void)
{
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_init: initializing\n"));
IP4_ADDR(&allsystems, 224, 0, 0, 1);
IP4_ADDR(&allrouters, 224, 0, 0, 2);
}
#ifdef LWIP_DEBUG
/**
* Dump global IGMP groups list
*/
void
igmp_dump_group_list()
{
struct igmp_group *group = igmp_group_list;
while (group != NULL) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_dump_group_list: [%"U32_F"] ", (u32_t)(group->group_state)));
ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
group = group->next;
}
LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
}
#else
#define igmp_dump_group_list()
#endif /* LWIP_DEBUG */
/**
* Start IGMP processing on interface
*
* @param netif network interface on which start IGMP processing
*/
err_t
igmp_start(struct netif *netif)
{
struct igmp_group* group;
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: starting IGMP processing on if %p\n", netif));
group = igmp_lookup_group(netif, &allsystems);
if (group != NULL) {
group->group_state = IGMP_GROUP_IDLE_MEMBER;
group->use++;
/* Allow the igmp messages at the MAC level */
if (netif->igmp_mac_filter != NULL) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_start: igmp_mac_filter(ADD "));
ip_addr_debug_print(IGMP_DEBUG, &allsystems);
LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
netif->igmp_mac_filter(netif, &allsystems, IGMP_ADD_MAC_FILTER);
}
return ERR_OK;
}
return ERR_MEM;
}
/**
* Stop IGMP processing on interface
*
* @param netif network interface on which stop IGMP processing
*/
err_t
igmp_stop(struct netif *netif)
{
struct igmp_group *group = igmp_group_list;
struct igmp_group *prev = NULL;
struct igmp_group *next;
/* look for groups joined on this interface further down the list */
while (group != NULL) {
next = group->next;
/* is it a group joined on this interface? */
if (group->netif == netif) {
/* is it the first group of the list? */
if (group == igmp_group_list) {
igmp_group_list = next;
}
/* is there a "previous" group defined? */
if (prev != NULL) {
prev->next = next;
}
/* disable the group at the MAC level */
if (netif->igmp_mac_filter != NULL) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_stop: igmp_mac_filter(DEL "));
ip_addr_debug_print(IGMP_DEBUG, &group->group_address);
LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
netif->igmp_mac_filter(netif, &(group->group_address), IGMP_DEL_MAC_FILTER);
}
/* free group */
memp_free(MEMP_IGMP_GROUP, group);
} else {
/* change the "previous" */
prev = group;
}
/* move to "next" */
group = next;
}
return ERR_OK;
}
/**
* Report IGMP memberships for this interface
*
* @param netif network interface on which report IGMP memberships
*/
void
igmp_report_groups(struct netif *netif)
{
struct igmp_group *group = igmp_group_list;
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_report_groups: sending IGMP reports on if %p\n", netif));
while (group != NULL) {
if (group->netif == netif) {
igmp_delaying_member(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
}
group = group->next;
}
}
/**
* Search for a group in the global igmp_group_list
*
* @param ifp the network interface for which to look
* @param addr the group ip address to search for
* @return a struct igmp_group* if the group has been found,
* NULL if the group wasn't found.
*/
struct igmp_group *
igmp_lookfor_group(struct netif *ifp, ip_addr_t *addr)
{
struct igmp_group *group = igmp_group_list;
while (group != NULL) {
if ((group->netif == ifp) && (ip_addr_cmp(&(group->group_address), addr))) {
return group;
}
group = group->next;
}
/* to be clearer, we return NULL here instead of
* 'group' (which is also NULL at this point).
*/
return NULL;
}
/**
* Search for a specific igmp group and create a new one if not found-
*
* @param ifp the network interface for which to look
* @param addr the group ip address to search
* @return a struct igmp_group*,
* NULL on memory error.
*/
struct igmp_group *
igmp_lookup_group(struct netif *ifp, ip_addr_t *addr)
{
struct igmp_group *group = igmp_group_list;
/* Search if the group already exists */
group = igmp_lookfor_group(ifp, addr);
if (group != NULL) {
/* Group already exists. */
return group;
}
/* Group doesn't exist yet, create a new one */
group = (struct igmp_group *)memp_malloc(MEMP_IGMP_GROUP);
if (group != NULL) {
group->netif = ifp;
ip_addr_set(&(group->group_address), addr);
group->timer = 0; /* Not running */
group->group_state = IGMP_GROUP_NON_MEMBER;
group->last_reporter_flag = 0;
group->use = 0;
group->next = igmp_group_list;
igmp_group_list = group;
}
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_lookup_group: %sallocated a new group with address ", (group?"":"impossible to ")));
ip_addr_debug_print(IGMP_DEBUG, addr);
LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", ifp));
return group;
}
/**
* Remove a group in the global igmp_group_list
*
* @param group the group to remove from the global igmp_group_list
* @return ERR_OK if group was removed from the list, an err_t otherwise
*/
static err_t
igmp_remove_group(struct igmp_group *group)
{
err_t err = ERR_OK;
/* Is it the first group? */
if (igmp_group_list == group) {
igmp_group_list = group->next;
} else {
/* look for group further down the list */
struct igmp_group *tmpGroup;
for (tmpGroup = igmp_group_list; tmpGroup != NULL; tmpGroup = tmpGroup->next) {
if (tmpGroup->next == group) {
tmpGroup->next = group->next;
break;
}
}
/* Group not found in the global igmp_group_list */
if (tmpGroup == NULL)
err = ERR_ARG;
}
/* free group */
memp_free(MEMP_IGMP_GROUP, group);
return err;
}
/**
* Called from ip_input() if a new IGMP packet is received.
*
* @param p received igmp packet, p->payload pointing to the ip header
* @param inp network interface on which the packet was received
* @param dest destination ip address of the igmp packet
*/
void
igmp_input(struct pbuf *p, struct netif *inp, ip_addr_t *dest)
{
struct ip_hdr * iphdr;
struct igmp_msg* igmp;
struct igmp_group* group;
struct igmp_group* groupref;
IGMP_STATS_INC(igmp.recv);
/* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */
iphdr = (struct ip_hdr *)p->payload;
if (pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
pbuf_free(p);
IGMP_STATS_INC(igmp.lenerr);
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
return;
}
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: message from "));
ip_addr_debug_print(IGMP_DEBUG, &(iphdr->src));
LWIP_DEBUGF(IGMP_DEBUG, (" to address "));
ip_addr_debug_print(IGMP_DEBUG, &(iphdr->dest));
LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", inp));
/* Now calculate and check the checksum */
igmp = (struct igmp_msg *)p->payload;
if (inet_chksum(igmp, p->len)) {
pbuf_free(p);
IGMP_STATS_INC(igmp.chkerr);
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: checksum error\n"));
return;
}
/* Packet is ok so find an existing group */
group = igmp_lookfor_group(inp, dest); /* use the destination IP address of incoming packet */
/* If group can be found or create... */
if (!group) {
pbuf_free(p);
IGMP_STATS_INC(igmp.drop);
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP frame not for us\n"));
return;
}
/* NOW ACT ON THE INCOMING MESSAGE TYPE... */
switch (igmp->igmp_msgtype) {
case IGMP_MEMB_QUERY: {
/* IGMP_MEMB_QUERY to the "all systems" address ? */
if ((ip_addr_cmp(dest, &allsystems)) && ip_addr_isany(&igmp->igmp_group_address)) {
/* THIS IS THE GENERAL QUERY */
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: General IGMP_MEMB_QUERY on \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
if (igmp->igmp_maxresp == 0) {
IGMP_STATS_INC(igmp.rx_v1);
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: got an all hosts query with time== 0 - this is V1 and not implemented - treat as v2\n"));
igmp->igmp_maxresp = IGMP_V1_DELAYING_MEMBER_TMR;
} else {
IGMP_STATS_INC(igmp.rx_general);
}
groupref = igmp_group_list;
while (groupref) {
/* Do not send messages on the all systems group address! */
if ((groupref->netif == inp) && (!(ip_addr_cmp(&(groupref->group_address), &allsystems)))) {
igmp_delaying_member(groupref, igmp->igmp_maxresp);
}
groupref = groupref->next;
}
} else {
/* IGMP_MEMB_QUERY to a specific group ? */
if (!ip_addr_isany(&igmp->igmp_group_address)) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_MEMB_QUERY to a specific group "));
ip_addr_debug_print(IGMP_DEBUG, &igmp->igmp_group_address);
if (ip_addr_cmp(dest, &allsystems)) {
ip_addr_t groupaddr;
LWIP_DEBUGF(IGMP_DEBUG, (" using \"ALL SYSTEMS\" address (224.0.0.1) [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
/* we first need to re-look for the group since we used dest last time */
ip_addr_copy(groupaddr, igmp->igmp_group_address);
group = igmp_lookfor_group(inp, &groupaddr);
} else {
LWIP_DEBUGF(IGMP_DEBUG, (" with the group address as destination [igmp_maxresp=%i]\n", (int)(igmp->igmp_maxresp)));
}
if (group != NULL) {
IGMP_STATS_INC(igmp.rx_group);
igmp_delaying_member(group, igmp->igmp_maxresp);
} else {
IGMP_STATS_INC(igmp.drop);
}
} else {
IGMP_STATS_INC(igmp.proterr);
}
}
break;
}
case IGMP_V2_MEMB_REPORT: {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: IGMP_V2_MEMB_REPORT\n"));
IGMP_STATS_INC(igmp.rx_report);
if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
/* This is on a specific group we have already looked up */
group->timer = 0; /* stopped */
group->group_state = IGMP_GROUP_IDLE_MEMBER;
group->last_reporter_flag = 0;
}
break;
}
default: {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: unexpected msg %d in state %d on group %p on if %p\n",
igmp->igmp_msgtype, group->group_state, &group, group->netif));
IGMP_STATS_INC(igmp.proterr);
break;
}
}
pbuf_free(p);
return;
}
/**
* Join a group on one network interface.
*
* @param ifaddr ip address of the network interface which should join a new group
* @param groupaddr the ip address of the group which to join
* @return ERR_OK if group was joined on the netif(s), an err_t otherwise
*/
err_t
igmp_joingroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
{
err_t err = ERR_VAL; /* no matching interface */
struct igmp_group *group;
struct netif *netif;
/* make sure it is multicast address */
LWIP_ERROR("igmp_joingroup: attempt to join non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
LWIP_ERROR("igmp_joingroup: attempt to join allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
/* loop through netif's */
netif = netif_list;
while (netif != NULL) {
/* Should we join this interface ? */
if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
/* find group or create a new one if not found */
group = igmp_lookup_group(netif, groupaddr);
if (group != NULL) {
/* This should create a new group, check the state to make sure */
if (group->group_state != IGMP_GROUP_NON_MEMBER) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to group not in state IGMP_GROUP_NON_MEMBER\n"));
} else {
/* OK - it was new group */
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: join to new group: "));
ip_addr_debug_print(IGMP_DEBUG, groupaddr);
LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
/* If first use of the group, allow the group at the MAC level */
if ((group->use==0) && (netif->igmp_mac_filter != NULL)) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: igmp_mac_filter(ADD "));
ip_addr_debug_print(IGMP_DEBUG, groupaddr);
LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
netif->igmp_mac_filter(netif, groupaddr, IGMP_ADD_MAC_FILTER);
}
IGMP_STATS_INC(igmp.tx_join);
igmp_send(group, IGMP_V2_MEMB_REPORT);
igmp_start_timer(group, IGMP_JOIN_DELAYING_MEMBER_TMR);
/* Need to work out where this timer comes from */
group->group_state = IGMP_GROUP_DELAYING_MEMBER;
}
/* Increment group use */
group->use++;
/* Join on this interface */
err = ERR_OK;
} else {
/* Return an error even if some network interfaces are joined */
/** @todo undo any other netif already joined */
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_joingroup: Not enought memory to join to group\n"));
return ERR_MEM;
}
}
/* proceed to next network interface */
netif = netif->next;
}
return err;
}
/**
* Leave a group on one network interface.
*
* @param ifaddr ip address of the network interface which should leave a group
* @param groupaddr the ip address of the group which to leave
* @return ERR_OK if group was left on the netif(s), an err_t otherwise
*/
err_t
igmp_leavegroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)
{
err_t err = ERR_VAL; /* no matching interface */
struct igmp_group *group;
struct netif *netif;
/* make sure it is multicast address */
LWIP_ERROR("igmp_leavegroup: attempt to leave non-multicast address", ip_addr_ismulticast(groupaddr), return ERR_VAL;);
LWIP_ERROR("igmp_leavegroup: attempt to leave allsystems address", (!ip_addr_cmp(groupaddr, &allsystems)), return ERR_VAL;);
/* loop through netif's */
netif = netif_list;
while (netif != NULL) {
/* Should we leave this interface ? */
if ((netif->flags & NETIF_FLAG_IGMP) && ((ip_addr_isany(ifaddr) || ip_addr_cmp(&(netif->ip_addr), ifaddr)))) {
/* find group */
group = igmp_lookfor_group(netif, groupaddr);
if (group != NULL) {
/* Only send a leave if the flag is set according to the state diagram */
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: Leaving group: "));
ip_addr_debug_print(IGMP_DEBUG, groupaddr);
LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
/* If there is no other use of the group */
if (group->use <= 1) {
/* If we are the last reporter for this group */
if (group->last_reporter_flag) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: sending leaving group\n"));
IGMP_STATS_INC(igmp.tx_leave);
igmp_send(group, IGMP_LEAVE_GROUP);
}
/* Disable the group at the MAC level */
if (netif->igmp_mac_filter != NULL) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: igmp_mac_filter(DEL "));
ip_addr_debug_print(IGMP_DEBUG, groupaddr);
LWIP_DEBUGF(IGMP_DEBUG, (") on if %p\n", netif));
netif->igmp_mac_filter(netif, groupaddr, IGMP_DEL_MAC_FILTER);
}
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: remove group: "));
ip_addr_debug_print(IGMP_DEBUG, groupaddr);
LWIP_DEBUGF(IGMP_DEBUG, ("\n"));
/* Free the group */
igmp_remove_group(group);
} else {
/* Decrement group use */
group->use--;
}
/* Leave on this interface */
err = ERR_OK;
} else {
/* It's not a fatal error on "leavegroup" */
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_leavegroup: not member of group\n"));
}
}
/* proceed to next network interface */
netif = netif->next;
}
return err;
}
/**
* The igmp timer function (both for NO_SYS=1 and =0)
* Should be called every IGMP_TMR_INTERVAL milliseconds (100 ms is default).
*/
void
igmp_tmr(void)
{
struct igmp_group *group = igmp_group_list;
while (group != NULL) {
if (group->timer > 0) {
group->timer--;
if (group->timer == 0) {
igmp_timeout(group);
}
}
group = group->next;
}
}
/**
* Called if a timeout for one group is reached.
* Sends a report for this group.
*
* @param group an igmp_group for which a timeout is reached
*/
static void
igmp_timeout(struct igmp_group *group)
{
/* If the state is IGMP_GROUP_DELAYING_MEMBER then we send a report for this group */
if (group->group_state == IGMP_GROUP_DELAYING_MEMBER) {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_timeout: report membership for group with address "));
ip_addr_debug_print(IGMP_DEBUG, &(group->group_address));
LWIP_DEBUGF(IGMP_DEBUG, (" on if %p\n", group->netif));
IGMP_STATS_INC(igmp.tx_report);
igmp_send(group, IGMP_V2_MEMB_REPORT);
}
}
/**
* Start a timer for an igmp group
*
* @param group the igmp_group for which to start a timer
* @param max_time the time in multiples of IGMP_TMR_INTERVAL (decrease with
* every call to igmp_tmr())
*/
static void
igmp_start_timer(struct igmp_group *group, u8_t max_time)
{
/* ensure the input value is > 0 */
if (max_time == 0) {
max_time = 1;
}
/* ensure the random value is > 0 */
group->timer = (LWIP_RAND() % (max_time - 1)) + 1;
}
/**
* Delaying membership report for a group if necessary
*
* @param group the igmp_group for which "delaying" membership report
* @param maxresp query delay
*/
static void
igmp_delaying_member(struct igmp_group *group, u8_t maxresp)
{
if ((group->group_state == IGMP_GROUP_IDLE_MEMBER) ||
((group->group_state == IGMP_GROUP_DELAYING_MEMBER) &&
((group->timer == 0) || (maxresp < group->timer)))) {
igmp_start_timer(group, maxresp);
group->group_state = IGMP_GROUP_DELAYING_MEMBER;
}
}
/**
* Sends an IP packet on a network interface. This function constructs the IP header
* and calculates the IP header checksum. If the source IP address is NULL,
* the IP address of the outgoing network interface is filled in as source address.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == IP_HDRINCL, p already includes an IP
header and p->payload points to that IP header)
* @param src the source IP address to send from (if src == IP_ADDR_ANY, the
* IP address of the netif used to send is used as source address)
* @param dest the destination IP address to send the packet to
* @param ttl the TTL value to be set in the IP header
* @param proto the PROTOCOL to be set in the IP header
* @param netif the netif on which to send this packet
* @return ERR_OK if the packet was sent OK
* ERR_BUF if p doesn't have enough space for IP/LINK headers
* returns errors returned by netif->output
*/
static err_t
igmp_ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest, struct netif *netif)
{
/* This is the "router alert" option */
u16_t ra[2];
ra[0] = PP_HTONS(ROUTER_ALERT);
ra[1] = 0x0000; /* Router shall examine packet */
IGMP_STATS_INC(igmp.xmit);
return ip_output_if_opt(p, src, dest, IGMP_TTL, 0, IP_PROTO_IGMP, netif, ra, ROUTER_ALERTLEN);
}
/**
* Send an igmp packet to a specific group.
*
* @param group the group to which to send the packet
* @param type the type of igmp packet to send
*/
static void
igmp_send(struct igmp_group *group, u8_t type)
{
struct pbuf* p = NULL;
struct igmp_msg* igmp = NULL;
ip_addr_t src = *IP_ADDR_ANY;
ip_addr_t* dest = NULL;
/* IP header + "router alert" option + IGMP header */
p = pbuf_alloc(PBUF_TRANSPORT, IGMP_MINLEN, PBUF_RAM);
if (p) {
igmp = (struct igmp_msg *)p->payload;
LWIP_ASSERT("igmp_send: check that first pbuf can hold struct igmp_msg",
(p->len >= sizeof(struct igmp_msg)));
ip_addr_copy(src, group->netif->ip_addr);
if (type == IGMP_V2_MEMB_REPORT) {
dest = &(group->group_address);
ip_addr_copy(igmp->igmp_group_address, group->group_address);
group->last_reporter_flag = 1; /* Remember we were the last to report */
} else {
if (type == IGMP_LEAVE_GROUP) {
dest = &allrouters;
ip_addr_copy(igmp->igmp_group_address, group->group_address);
}
}
if ((type == IGMP_V2_MEMB_REPORT) || (type == IGMP_LEAVE_GROUP)) {
igmp->igmp_msgtype = type;
igmp->igmp_maxresp = 0;
igmp->igmp_checksum = 0;
igmp->igmp_checksum = inet_chksum(igmp, IGMP_MINLEN);
igmp_ip_output_if(p, &src, dest, group->netif);
}
pbuf_free(p);
} else {
LWIP_DEBUGF(IGMP_DEBUG, ("igmp_send: not enough memory for igmp_send\n"));
IGMP_STATS_INC(igmp.memerr);
}
}
#endif /* LWIP_IGMP */

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/**
* @file
* Functions common to all TCP/IPv4 modules, such as the byte order functions.
*
*/
/*
* 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"
#if defined(__APPLE__)
#include "TargetConditionals.h"
#if !defined(TARGET_IPHONE_SIMULATOR) && !defined(TARGET_OS_IPHONE)
#include "lwip/inet.h"
#endif
#endif

450
ext/lwip/src/core/ipv4/inet_chksum.c Normal file
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/**
* @file
* Incluse internet checksum functions.
*
*/
/*
* 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/inet_chksum.h"
#include "lwip/def.h"
#include <stddef.h>
#include <string.h>
/* These are some reference implementations of the checksum algorithm, with the
* aim of being simple, correct and fully portable. Checksumming is the
* first thing you would want to optimize for your platform. If you create
* your own version, link it in and in your cc.h put:
*
* #define LWIP_CHKSUM <your_checksum_routine>
*
* Or you can select from the implementations below by defining
* LWIP_CHKSUM_ALGORITHM to 1, 2 or 3.
*/
#ifndef LWIP_CHKSUM
# define LWIP_CHKSUM lwip_standard_chksum
# ifndef LWIP_CHKSUM_ALGORITHM
# define LWIP_CHKSUM_ALGORITHM 2
# endif
#endif
/* If none set: */
#ifndef LWIP_CHKSUM_ALGORITHM
# define LWIP_CHKSUM_ALGORITHM 0
#endif
#if (LWIP_CHKSUM_ALGORITHM == 1) /* Version #1 */
/**
* lwip checksum
*
* @param dataptr points to start of data to be summed at any boundary
* @param len length of data to be summed
* @return host order (!) lwip checksum (non-inverted Internet sum)
*
* @note accumulator size limits summable length to 64k
* @note host endianess is irrelevant (p3 RFC1071)
*/
static u16_t
lwip_standard_chksum(void *dataptr, u16_t len)
{
u32_t acc;
u16_t src;
u8_t *octetptr;
acc = 0;
/* dataptr may be at odd or even addresses */
octetptr = (u8_t*)dataptr;
while (len > 1) {
/* declare first octet as most significant
thus assume network order, ignoring host order */
src = (*octetptr) << 8;
octetptr++;
/* declare second octet as least significant */
src |= (*octetptr);
octetptr++;
acc += src;
len -= 2;
}
if (len > 0) {
/* accumulate remaining octet */
src = (*octetptr) << 8;
acc += src;
}
/* add deferred carry bits */
acc = (acc >> 16) + (acc & 0x0000ffffUL);
if ((acc & 0xffff0000UL) != 0) {
acc = (acc >> 16) + (acc & 0x0000ffffUL);
}
/* This maybe a little confusing: reorder sum using htons()
instead of ntohs() since it has a little less call overhead.
The caller must invert bits for Internet sum ! */
return htons((u16_t)acc);
}
#endif
#if (LWIP_CHKSUM_ALGORITHM == 2) /* Alternative version #2 */
/*
* Curt McDowell
* Broadcom Corp.
* csm@broadcom.com
*
* IP checksum two bytes at a time with support for
* unaligned buffer.
* Works for len up to and including 0x20000.
* by Curt McDowell, Broadcom Corp. 12/08/2005
*
* @param dataptr points to start of data to be summed at any boundary
* @param len length of data to be summed
* @return host order (!) lwip checksum (non-inverted Internet sum)
*/
static u16_t
lwip_standard_chksum(void *dataptr, int len)
{
u8_t *pb = (u8_t *)dataptr;
u16_t *ps, t = 0;
u32_t sum = 0;
int odd = ((mem_ptr_t)pb & 1);
/* Get aligned to u16_t */
if (odd && len > 0) {
((u8_t *)&t)[1] = *pb++;
len--;
}
/* Add the bulk of the data */
ps = (u16_t *)(void *)pb;
while (len > 1) {
sum += *ps++;
len -= 2;
}
/* Consume left-over byte, if any */
if (len > 0) {
((u8_t *)&t)[0] = *(u8_t *)ps;
}
/* Add end bytes */
sum += t;
/* Fold 32-bit sum to 16 bits
calling this twice is propably faster than if statements... */
sum = FOLD_U32T(sum);
sum = FOLD_U32T(sum);
/* Swap if alignment was odd */
if (odd) {
sum = SWAP_BYTES_IN_WORD(sum);
}
return (u16_t)sum;
}
#endif
#if (LWIP_CHKSUM_ALGORITHM == 3) /* Alternative version #3 */
/**
* An optimized checksum routine. Basically, it uses loop-unrolling on
* the checksum loop, treating the head and tail bytes specially, whereas
* the inner loop acts on 8 bytes at a time.
*
* @arg start of buffer to be checksummed. May be an odd byte address.
* @len number of bytes in the buffer to be checksummed.
* @return host order (!) lwip checksum (non-inverted Internet sum)
*
* by Curt McDowell, Broadcom Corp. December 8th, 2005
*/
static u16_t
lwip_standard_chksum(void *dataptr, int len)
{
u8_t *pb = (u8_t *)dataptr;
u16_t *ps, t = 0;
u32_t *pl;
u32_t sum = 0, tmp;
/* starts at odd byte address? */
int odd = ((mem_ptr_t)pb & 1);
if (odd && len > 0) {
((u8_t *)&t)[1] = *pb++;
len--;
}
ps = (u16_t *)pb;
if (((mem_ptr_t)ps & 3) && len > 1) {
sum += *ps++;
len -= 2;
}
pl = (u32_t *)ps;
while (len > 7) {
tmp = sum + *pl++; /* ping */
if (tmp < sum) {
tmp++; /* add back carry */
}
sum = tmp + *pl++; /* pong */
if (sum < tmp) {
sum++; /* add back carry */
}
len -= 8;
}
/* make room in upper bits */
sum = FOLD_U32T(sum);
ps = (u16_t *)pl;
/* 16-bit aligned word remaining? */
while (len > 1) {
sum += *ps++;
len -= 2;
}
/* dangling tail byte remaining? */
if (len > 0) { /* include odd byte */
((u8_t *)&t)[0] = *(u8_t *)ps;
}
sum += t; /* add end bytes */
/* Fold 32-bit sum to 16 bits
calling this twice is propably faster than if statements... */
sum = FOLD_U32T(sum);
sum = FOLD_U32T(sum);
if (odd) {
sum = SWAP_BYTES_IN_WORD(sum);
}
return (u16_t)sum;
}
#endif
/* inet_chksum_pseudo:
*
* Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
* IP addresses are expected to be in network byte order.
*
* @param p chain of pbufs over that a checksum should be calculated (ip data part)
* @param src source ip address (used for checksum of pseudo header)
* @param dst destination ip address (used for checksum of pseudo header)
* @param proto ip protocol (used for checksum of pseudo header)
* @param proto_len length of the ip data part (used for checksum of pseudo header)
* @return checksum (as u16_t) to be saved directly in the protocol header
*/
u16_t
inet_chksum_pseudo(struct pbuf *p,
ip_addr_t *src, ip_addr_t *dest,
u8_t proto, u16_t proto_len)
{
u32_t acc;
u32_t addr;
struct pbuf *q;
u8_t swapped;
acc = 0;
swapped = 0;
/* iterate through all pbuf in chain */
for(q = p; q != NULL; q = q->next) {
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
(void *)q, (void *)q->next));
acc += LWIP_CHKSUM(q->payload, q->len);
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
/* just executing this next line is probably faster that the if statement needed
to check whether we really need to execute it, and does no harm */
acc = FOLD_U32T(acc);
if (q->len % 2 != 0) {
swapped = 1 - swapped;
acc = SWAP_BYTES_IN_WORD(acc);
}
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
}
if (swapped) {
acc = SWAP_BYTES_IN_WORD(acc);
}
addr = ip4_addr_get_u32(src);
acc += (addr & 0xffffUL);
acc += ((addr >> 16) & 0xffffUL);
addr = ip4_addr_get_u32(dest);
acc += (addr & 0xffffUL);
acc += ((addr >> 16) & 0xffffUL);
acc += (u32_t)htons((u16_t)proto);
acc += (u32_t)htons(proto_len);
/* Fold 32-bit sum to 16 bits
calling this twice is propably faster than if statements... */
acc = FOLD_U32T(acc);
acc = FOLD_U32T(acc);
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
return (u16_t)~(acc & 0xffffUL);
}
/* inet_chksum_pseudo:
*
* Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
* IP addresses are expected to be in network byte order.
*
* @param p chain of pbufs over that a checksum should be calculated (ip data part)
* @param src source ip address (used for checksum of pseudo header)
* @param dst destination ip address (used for checksum of pseudo header)
* @param proto ip protocol (used for checksum of pseudo header)
* @param proto_len length of the ip data part (used for checksum of pseudo header)
* @return checksum (as u16_t) to be saved directly in the protocol header
*/
u16_t
inet_chksum_pseudo_partial(struct pbuf *p,
ip_addr_t *src, ip_addr_t *dest,
u8_t proto, u16_t proto_len, u16_t chksum_len)
{
u32_t acc;
u32_t addr;
struct pbuf *q;
u8_t swapped;
u16_t chklen;
acc = 0;
swapped = 0;
/* iterate through all pbuf in chain */
for(q = p; (q != NULL) && (chksum_len > 0); q = q->next) {
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
(void *)q, (void *)q->next));
chklen = q->len;
if (chklen > chksum_len) {
chklen = chksum_len;
}
acc += LWIP_CHKSUM(q->payload, chklen);
chksum_len -= chklen;
LWIP_ASSERT("delete me", chksum_len < 0x7fff);
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
/* fold the upper bit down */
acc = FOLD_U32T(acc);
if (q->len % 2 != 0) {
swapped = 1 - swapped;
acc = SWAP_BYTES_IN_WORD(acc);
}
/*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
}
if (swapped) {
acc = SWAP_BYTES_IN_WORD(acc);
}
addr = ip4_addr_get_u32(src);
acc += (addr & 0xffffUL);
acc += ((addr >> 16) & 0xffffUL);
addr = ip4_addr_get_u32(dest);
acc += (addr & 0xffffUL);
acc += ((addr >> 16) & 0xffffUL);
acc += (u32_t)htons((u16_t)proto);
acc += (u32_t)htons(proto_len);
/* Fold 32-bit sum to 16 bits
calling this twice is propably faster than if statements... */
acc = FOLD_U32T(acc);
acc = FOLD_U32T(acc);
LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
return (u16_t)~(acc & 0xffffUL);
}
/* inet_chksum:
*
* Calculates the Internet checksum over a portion of memory. Used primarily for IP
* and ICMP.
*
* @param dataptr start of the buffer to calculate the checksum (no alignment needed)
* @param len length of the buffer to calculate the checksum
* @return checksum (as u16_t) to be saved directly in the protocol header
*/
u16_t
inet_chksum(void *dataptr, u16_t len)
{
return ~LWIP_CHKSUM(dataptr, len);
}
/**
* Calculate a checksum over a chain of pbufs (without pseudo-header, much like
* inet_chksum only pbufs are used).
*
* @param p pbuf chain over that the checksum should be calculated
* @return checksum (as u16_t) to be saved directly in the protocol header
*/
u16_t
inet_chksum_pbuf(struct pbuf *p)
{
u32_t acc;
struct pbuf *q;
u8_t swapped;
acc = 0;
swapped = 0;
for(q = p; q != NULL; q = q->next) {
acc += LWIP_CHKSUM(q->payload, q->len);
acc = FOLD_U32T(acc);
if (q->len % 2 != 0) {
swapped = 1 - swapped;
acc = SWAP_BYTES_IN_WORD(acc);
}
}
if (swapped) {
acc = SWAP_BYTES_IN_WORD(acc);
}
return (u16_t)~(acc & 0xffffUL);
}
/* These are some implementations for LWIP_CHKSUM_COPY, which copies data
* like MEMCPY but generates a checksum at the same time. Since this is a
* performance-sensitive function, you might want to create your own version
* in assembly targeted at your hardware by defining it in lwipopts.h:
* #define LWIP_CHKSUM_COPY(dst, src, len) your_chksum_copy(dst, src, len)
*/
#if (LWIP_CHKSUM_COPY_ALGORITHM == 1) /* Version #1 */
/** Safe but slow: first call MEMCPY, then call LWIP_CHKSUM.
* For architectures with big caches, data might still be in cache when
* generating the checksum after copying.
*/
u16_t
lwip_chksum_copy(void *dst, const void *src, u16_t len)
{
MEMCPY(dst, src, len);
return LWIP_CHKSUM(dst, len);
}
#endif /* (LWIP_CHKSUM_COPY_ALGORITHM == 1) */

924
ext/lwip/src/core/ipv4/ip.c Normal file
View File

@@ -0,0 +1,924 @@
/**
* @file
* This is the IPv4 layer implementation for incoming and outgoing IP traffic.
*
* @see ip_frag.c
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/opt.h"
#include "lwip/ip.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/ip_frag.h"
#include "lwip/inet_chksum.h"
#include "lwip/netif.h"
#include "lwip/icmp.h"
#include "lwip/igmp.h"
#include "lwip/raw.h"
#include "lwip/udp.h"
#include "lwip/tcp_impl.h"
#include "lwip/snmp.h"
#include "lwip/dhcp.h"
#include "lwip/autoip.h"
#include "lwip/stats.h"
#include "arch/perf.h"
#include <string.h>
/** Set this to 0 in the rare case of wanting to call an extra function to
* generate the IP checksum (in contrast to calculating it on-the-fly). */
#ifndef LWIP_INLINE_IP_CHKSUM
#define LWIP_INLINE_IP_CHKSUM 1
#endif
#if LWIP_INLINE_IP_CHKSUM && CHECKSUM_GEN_IP
#define CHECKSUM_GEN_IP_INLINE 1
#else
#define CHECKSUM_GEN_IP_INLINE 0
#endif
#if LWIP_DHCP || defined(LWIP_IP_ACCEPT_UDP_PORT)
#define IP_ACCEPT_LINK_LAYER_ADDRESSING 1
/** Some defines for DHCP to let link-layer-addressed packets through while the
* netif is down.
* To use this in your own application/protocol, define LWIP_IP_ACCEPT_UDP_PORT
* to return 1 if the port is accepted and 0 if the port is not accepted.
*/
#if LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT)
/* accept DHCP client port and custom port */
#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (((port) == PP_NTOHS(DHCP_CLIENT_PORT)) \
|| (LWIP_IP_ACCEPT_UDP_PORT(port)))
#elif defined(LWIP_IP_ACCEPT_UDP_PORT) /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
/* accept custom port only */
#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) (LWIP_IP_ACCEPT_UDP_PORT(port))
#else /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
/* accept DHCP client port only */
#define IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(port) ((port) == PP_NTOHS(DHCP_CLIENT_PORT))
#endif /* LWIP_DHCP && defined(LWIP_IP_ACCEPT_UDP_PORT) */
#else /* LWIP_DHCP */
#define IP_ACCEPT_LINK_LAYER_ADDRESSING 0
#endif /* LWIP_DHCP */
/**
* The interface that provided the packet for the current callback
* invocation.
*/
struct netif *current_netif;
/**
* Header of the input packet currently being processed.
*/
const struct ip_hdr *current_header;
/** Source IP address of current_header */
ip_addr_t current_iphdr_src;
/** Destination IP address of current_header */
ip_addr_t current_iphdr_dest;
/** The IP header ID of the next outgoing IP packet */
static u16_t ip_id;
/**
* Finds the appropriate network interface for a given IP address. It
* searches the list of network interfaces linearly. A match is found
* if the masked IP address of the network interface equals the masked
* IP address given to the function.
*
* @param dest the destination IP address for which to find the route
* @return the netif on which to send to reach dest
*/
struct netif *
ip_route(ip_addr_t *dest)
{
struct netif *netif;
#ifdef LWIP_HOOK_IP4_ROUTE
netif = LWIP_HOOK_IP4_ROUTE(dest);
if (netif != NULL) {
return netif;
}
#endif
/* iterate through netifs */
for (netif = netif_list; netif != NULL; netif = netif->next) {
/* network mask matches? */
if (netif_is_up(netif)) {
if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
/* return netif on which to forward IP packet */
return netif;
}
}
}
if ((netif_default == NULL) || (!netif_is_up(netif_default))) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_route: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
IP_STATS_INC(ip.rterr);
snmp_inc_ipoutnoroutes();
return NULL;
}
/* no matching netif found, use default netif */
return netif_default;
}
#if IP_FORWARD
/**
* Determine whether an IP address is in a reserved set of addresses
* that may not be forwarded, or whether datagrams to that destination
* may be forwarded.
* @param p the packet to forward
* @param dest the destination IP address
* @return 1: can forward 0: discard
*/
static int
ip_canforward(struct pbuf *p)
{
u32_t addr = ip4_addr_get_u32(ip_current_dest_addr());
if (p->flags & PBUF_FLAG_LLBCAST) {
/* don't route link-layer broadcasts */
return 0;
}
if ((p->flags & PBUF_FLAG_LLMCAST) && !IP_MULTICAST(addr)) {
/* don't route link-layer multicasts unless the destination address is an IP
multicast address */
return 0;
}
if (IP_EXPERIMENTAL(addr)) {
return 0;
}
if (IP_CLASSA(addr)) {
u32_t net = addr & IP_CLASSA_NET;
if ((net == 0) || (net == (IP_LOOPBACKNET << IP_CLASSA_NSHIFT))) {
/* don't route loopback packets */
return 0;
}
}
return 1;
}
/**
* Forwards an IP packet. It finds an appropriate route for the
* packet, decrements the TTL value of the packet, adjusts the
* checksum and outputs the packet on the appropriate interface.
*
* @param p the packet to forward (p->payload points to IP header)
* @param iphdr the IP header of the input packet
* @param inp the netif on which this packet was received
*/
static void
ip_forward(struct pbuf *p, struct ip_hdr *iphdr, struct netif *inp)
{
struct netif *netif;
PERF_START;
if (!ip_canforward(p)) {
goto return_noroute;
}
/* RFC3927 2.7: do not forward link-local addresses */
if (ip_addr_islinklocal(&current_iphdr_dest)) {
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not forwarding LLA %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
goto return_noroute;
}
/* Find network interface where to forward this IP packet to. */
netif = ip_route(&current_iphdr_dest);
if (netif == NULL) {
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: no forwarding route for %"U16_F".%"U16_F".%"U16_F".%"U16_F" found\n",
ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
/* @todo: send ICMP_DUR_NET? */
goto return_noroute;
}
#if !IP_FORWARD_ALLOW_TX_ON_RX_NETIF
/* Do not forward packets onto the same network interface on which
* they arrived. */
if (netif == inp) {
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: not bouncing packets back on incoming interface.\n"));
goto return_noroute;
}
#endif /* IP_FORWARD_ALLOW_TX_ON_RX_NETIF */
/* decrement TTL */
IPH_TTL_SET(iphdr, IPH_TTL(iphdr) - 1);
/* send ICMP if TTL == 0 */
if (IPH_TTL(iphdr) == 0) {
snmp_inc_ipinhdrerrors();
#if LWIP_ICMP
/* Don't send ICMP messages in response to ICMP messages */
if (IPH_PROTO(iphdr) != IP_PROTO_ICMP) {
icmp_time_exceeded(p, ICMP_TE_TTL);
}
#endif /* LWIP_ICMP */
return;
}
/* Incrementally update the IP checksum. */
if (IPH_CHKSUM(iphdr) >= PP_HTONS(0xffffU - 0x100)) {
IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100) + 1);
} else {
IPH_CHKSUM_SET(iphdr, IPH_CHKSUM(iphdr) + PP_HTONS(0x100));
}
LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(&current_iphdr_dest), ip4_addr2_16(&current_iphdr_dest),
ip4_addr3_16(&current_iphdr_dest), ip4_addr4_16(&current_iphdr_dest)));
IP_STATS_INC(ip.fw);
IP_STATS_INC(ip.xmit);
snmp_inc_ipforwdatagrams();
PERF_STOP("ip_forward");
/* don't fragment if interface has mtu set to 0 [loopif] */
if (netif->mtu && (p->tot_len > netif->mtu)) {
if ((IPH_OFFSET(iphdr) & PP_NTOHS(IP_DF)) == 0) {
#if IP_FRAG
ip_frag(p, netif, ip_current_dest_addr());
#else /* IP_FRAG */
/* @todo: send ICMP Destination Unreacheable code 13 "Communication administratively prohibited"? */
#endif /* IP_FRAG */
} else {
/* send ICMP Destination Unreacheable code 4: "Fragmentation Needed and DF Set" */
icmp_dest_unreach(p, ICMP_DUR_FRAG);
}
return;
}
/* transmit pbuf on chosen interface */
netif->output(netif, p, &current_iphdr_dest);
return;
return_noroute:
snmp_inc_ipoutnoroutes();
}
#endif /* IP_FORWARD */
/**
* This function is called by the network interface device driver when
* an IP packet is received. The function does the basic checks of the
* IP header such as packet size being at least larger than the header
* size etc. If the packet was not destined for us, the packet is
* forwarded (using ip_forward). The IP checksum is always checked.
*
* Finally, the packet is sent to the upper layer protocol input function.
*
* @param p the received IP packet (p->payload points to IP header)
* @param inp the netif on which this packet was received
* @return ERR_OK if the packet was processed (could return ERR_* if it wasn't
* processed, but currently always returns ERR_OK)
*/
err_t
ip_input(struct pbuf *p, struct netif *inp)
{
struct ip_hdr *iphdr;
struct netif *netif;
u16_t iphdr_hlen;
u16_t iphdr_len;
#if IP_ACCEPT_LINK_LAYER_ADDRESSING
int check_ip_src=1;
#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
IP_STATS_INC(ip.recv);
snmp_inc_ipinreceives();
/* identify the IP header */
iphdr = (struct ip_hdr *)p->payload;
if (IPH_V(iphdr) != 4) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_WARNING, ("IP packet dropped due to bad version number %"U16_F"\n", 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;
}
#ifdef LWIP_HOOK_IP4_INPUT
if (LWIP_HOOK_IP4_INPUT(p, inp)) {
/* the packet has been eaten */
return ERR_OK;
}
#endif
/* obtain IP header length in number of 32-bit words */
iphdr_hlen = IPH_HL(iphdr);
/* calculate IP header length in bytes */
iphdr_hlen *= 4;
/* obtain ip length in bytes */
iphdr_len = ntohs(IPH_LEN(iphdr));
/* header length exceeds first pbuf length, or ip length exceeds total pbuf length? */
if ((iphdr_hlen > p->len) || (iphdr_len > p->tot_len)) {
if (iphdr_hlen > p->len) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IP header (len %"U16_F") does not fit in first pbuf (len %"U16_F"), IP packet dropped.\n",
iphdr_hlen, p->len));
}
if (iphdr_len > p->tot_len) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("IP (len %"U16_F") is longer than pbuf (len %"U16_F"), IP packet dropped.\n",
iphdr_len, p->tot_len));
}
/* free (drop) packet pbufs */
pbuf_free(p);
IP_STATS_INC(ip.lenerr);
IP_STATS_INC(ip.drop);
snmp_inc_ipindiscards();
return ERR_OK;
}
/* verify checksum */
#if CHECKSUM_CHECK_IP
if (inet_chksum(iphdr, iphdr_hlen) != 0) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("Checksum (0x%"X16_F") failed, IP packet dropped.\n", inet_chksum(iphdr, iphdr_hlen)));
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, iphdr_len);
/* copy IP addresses to aligned ip_addr_t */
ip_addr_copy(current_iphdr_dest, iphdr->dest);
ip_addr_copy(current_iphdr_src, iphdr->src);
/* match packet against an interface, i.e. is this packet for us? */
#if LWIP_IGMP
if (ip_addr_ismulticast(&current_iphdr_dest)) {
if ((inp->flags & NETIF_FLAG_IGMP) && (igmp_lookfor_group(inp, &current_iphdr_dest))) {
netif = inp;
} else {
netif = NULL;
}
} else
#endif /* LWIP_IGMP */
{
/* start trying with inp. if that's not acceptable, start walking the
list of configured netifs.
'first' is used as a boolean to mark whether we started walking the list */
int first = 1;
netif = inp;
do {
LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest 0x%"X32_F" netif->ip_addr 0x%"X32_F" (0x%"X32_F", 0x%"X32_F", 0x%"X32_F")\n",
ip4_addr_get_u32(&iphdr->dest), ip4_addr_get_u32(&netif->ip_addr),
ip4_addr_get_u32(&iphdr->dest) & ip4_addr_get_u32(&netif->netmask),
ip4_addr_get_u32(&netif->ip_addr) & ip4_addr_get_u32(&netif->netmask),
ip4_addr_get_u32(&iphdr->dest) & ~ip4_addr_get_u32(&netif->netmask)));
/* 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(&current_iphdr_dest, &(netif->ip_addr)) ||
/* or broadcast on this interface network address? */
ip_addr_isbroadcast(&current_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_AUTOIP
/* connections to link-local addresses must persist after changing
the netif's address (RFC3927 ch. 1.9) */
if ((netif->autoip != NULL) &&
ip_addr_cmp(&current_iphdr_dest, &(netif->autoip->llipaddr))) {
LWIP_DEBUGF(IP_DEBUG, ("ip_input: LLA packet accepted on interface %c%c\n",
netif->name[0], netif->name[1]));
/* break out of for loop */
break;
}
#endif /* LWIP_AUTOIP */
}
if (first) {
first = 0;
netif = netif_list;
} else {
netif = netif->next;
}
if (netif == inp) {
netif = netif->next;
}
} while(netif != NULL);
}
#if IP_ACCEPT_LINK_LAYER_ADDRESSING
/* Pass DHCP messages regardless of destination address. DHCP traffic is addressed
* using link layer addressing (such as Ethernet MAC) so we must not filter on IP.
* According to RFC 1542 section 3.1.1, referred by RFC 2131).
*
* If you want to accept private broadcast communication while a netif is down,
* define LWIP_IP_ACCEPT_UDP_PORT(dst_port), e.g.:
*
* #define LWIP_IP_ACCEPT_UDP_PORT(dst_port) ((dst_port) == PP_NTOHS(12345))
*/
if (netif == NULL) {
/* remote port is DHCP server? */
if (IPH_PROTO(iphdr) == IP_PROTO_UDP) {
struct udp_hdr *udphdr = (struct udp_hdr *)((u8_t *)iphdr + iphdr_hlen);
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: UDP packet to DHCP client port %"U16_F"\n",
ntohs(udphdr->dest)));
if (IP_ACCEPT_LINK_LAYER_ADDRESSED_PORT(udphdr->dest)) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: DHCP packet accepted.\n"));
netif = inp;
check_ip_src = 0;
}
}
}
#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
/* broadcast or multicast packet source address? Compliant with RFC 1122: 3.2.1.3 */
#if IP_ACCEPT_LINK_LAYER_ADDRESSING
/* DHCP servers need 0.0.0.0 to be allowed as source address (RFC 1.1.2.2: 3.2.1.3/a) */
if (check_ip_src && !ip_addr_isany(&current_iphdr_src))
#endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
{ if ((ip_addr_isbroadcast(&current_iphdr_src, inp)) ||
(ip_addr_ismulticast(&current_iphdr_src))) {
/* packet source is not valid */
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, ("ip_input: packet source is not valid.\n"));
/* free (drop) packet pbufs */
pbuf_free(p);
IP_STATS_INC(ip.drop);
snmp_inc_ipinaddrerrors();
snmp_inc_ipindiscards();
return ERR_OK;
}
}
/* packet not for us? */
if (netif == NULL) {
/* packet not for us, route or discard */
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
#if IP_FORWARD
/* non-broadcast packet? */
if (!ip_addr_isbroadcast(&current_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) & PP_HTONS(IP_OFFMASK | IP_MF)) != 0) {
#if IP_REASSEMBLY /* packet fragment reassembly code present? */
LWIP_DEBUGF(IP_DEBUG, ("IP packet is a fragment (id=0x%04"X16_F" tot_len=%"U16_F" len=%"U16_F" MF=%"U16_F" offset=%"U16_F"), calling ip_reass()\n",
ntohs(IPH_ID(iphdr)), p->tot_len, ntohs(IPH_LEN(iphdr)), !!(IPH_OFFSET(iphdr) & PP_HTONS(IP_MF)), (ntohs(IPH_OFFSET(iphdr)) & IP_OFFMASK)*8));
/* reassemble the packet*/
p = ip_reass(p);
/* packet not fully reassembled yet? */
if (p == NULL) {
return ERR_OK;
}
iphdr = (struct ip_hdr *)p->payload;
#else /* IP_REASSEMBLY == 0, no packet fragment reassembly code present */
pbuf_free(p);
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since it was fragmented (0x%"X16_F") (while IP_REASSEMBLY == 0).\n",
ntohs(IPH_OFFSET(iphdr))));
IP_STATS_INC(ip.opterr);
IP_STATS_INC(ip.drop);
/* unsupported protocol feature */
snmp_inc_ipinunknownprotos();
return ERR_OK;
#endif /* IP_REASSEMBLY */
}
#if IP_OPTIONS_ALLOWED == 0 /* no support for IP options in the IP header? */
#if LWIP_IGMP
/* there is an extra "router alert" option in IGMP messages which we allow for but do not police */
if((iphdr_hlen > IP_HLEN) && (IPH_PROTO(iphdr) != IP_PROTO_IGMP)) {
#else
if (iphdr_hlen > IP_HLEN) {
#endif /* LWIP_IGMP */
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("IP packet dropped since there were IP options (while IP_OPTIONS_ALLOWED == 0).\n"));
pbuf_free(p);
IP_STATS_INC(ip.opterr);
IP_STATS_INC(ip.drop);
/* unsupported protocol feature */
snmp_inc_ipinunknownprotos();
return ERR_OK;
}
#endif /* IP_OPTIONS_ALLOWED == 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));
current_netif = inp;
current_header = iphdr;
#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:
#if LWIP_UDPLITE
case IP_PROTO_UDPLITE:
#endif /* LWIP_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 */
#if LWIP_ICMP
case IP_PROTO_ICMP:
snmp_inc_ipindelivers();
icmp_input(p, inp);
break;
#endif /* LWIP_ICMP */
#if LWIP_IGMP
case IP_PROTO_IGMP:
igmp_input(p, inp, &current_iphdr_dest);
break;
#endif /* LWIP_IGMP */
default:
#if LWIP_ICMP
/* send ICMP destination protocol unreachable unless is was a broadcast */
if (!ip_addr_isbroadcast(&current_iphdr_dest, inp) &&
!ip_addr_ismulticast(&current_iphdr_dest)) {
p->payload = iphdr;
icmp_dest_unreach(p, ICMP_DUR_PROTO);
}
#endif /* LWIP_ICMP */
pbuf_free(p);
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("Unsupported transport protocol %"U16_F"\n", IPH_PROTO(iphdr)));
IP_STATS_INC(ip.proterr);
IP_STATS_INC(ip.drop);
snmp_inc_ipinunknownprotos();
}
}
current_netif = NULL;
current_header = NULL;
ip_addr_set_any(&current_iphdr_src);
ip_addr_set_any(&current_iphdr_dest);
return ERR_OK;
}
/**
* Sends an IP packet on a network interface. This function constructs
* the IP header and calculates the IP header checksum. If the source
* IP address is NULL, the IP address of the outgoing network
* interface is filled in as source address.
* If the destination IP address is IP_HDRINCL, p is assumed to already
* include an IP header and p->payload points to it instead of the data.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == IP_HDRINCL, p already includes an IP
header and p->payload points to that IP header)
* @param src the source IP address to send from (if src == IP_ADDR_ANY, the
* IP address of the netif used to send is used as source address)
* @param dest the destination IP address to send the packet to
* @param ttl the TTL value to be set in the IP header
* @param tos the TOS value to be set in the IP header
* @param proto the PROTOCOL to be set in the IP header
* @param netif the netif on which to send this packet
* @return ERR_OK if the packet was sent OK
* ERR_BUF if p doesn't have enough space for IP/LINK headers
* returns errors returned by netif->output
*
* @note ip_id: RFC791 "some host may be able to simply use
* unique identifiers independent of destination"
*/
err_t
ip_output_if(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
u8_t ttl, u8_t tos,
u8_t proto, struct netif *netif)
{
#if IP_OPTIONS_SEND
return ip_output_if_opt(p, src, dest, ttl, tos, proto, netif, NULL, 0);
}
/**
* Same as ip_output_if() but with the possibility to include IP options:
*
* @ param ip_options pointer to the IP options, copied into the IP header
* @ param optlen length of ip_options
*/
err_t ip_output_if_opt(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
u8_t ttl, u8_t tos, u8_t proto, struct netif *netif, void *ip_options,
u16_t optlen)
{
#endif /* IP_OPTIONS_SEND */
struct ip_hdr *iphdr;
ip_addr_t dest_addr;
#if CHECKSUM_GEN_IP_INLINE
u32_t chk_sum = 0;
#endif /* CHECKSUM_GEN_IP_INLINE */
/* pbufs passed to IP must have a ref-count of 1 as their payload pointer
gets altered as the packet is passed down the stack */
LWIP_ASSERT("p->ref == 1", p->ref == 1);
snmp_inc_ipoutrequests();
/* Should the IP header be generated or is it already included in p? */
if (dest != IP_HDRINCL) {
u16_t ip_hlen = IP_HLEN;
#if IP_OPTIONS_SEND
u16_t optlen_aligned = 0;
if (optlen != 0) {
#if CHECKSUM_GEN_IP_INLINE
int i;
#endif /* CHECKSUM_GEN_IP_INLINE */
/* round up to a multiple of 4 */
optlen_aligned = ((optlen + 3) & ~3);
ip_hlen += optlen_aligned;
/* First write in the IP options */
if (pbuf_header(p, optlen_aligned)) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output_if_opt: not enough room for IP options in pbuf\n"));
IP_STATS_INC(ip.err);
snmp_inc_ipoutdiscards();
return ERR_BUF;
}
MEMCPY(p->payload, ip_options, optlen);
if (optlen < optlen_aligned) {
/* zero the remaining bytes */
memset(((char*)p->payload) + optlen, 0, optlen_aligned - optlen);
}
#if CHECKSUM_GEN_IP_INLINE
for (i = 0; i < optlen_aligned/2; i++) {
chk_sum += ((u16_t*)p->payload)[i];
}
#endif /* CHECKSUM_GEN_IP_INLINE */
}
#endif /* IP_OPTIONS_SEND */
/* generate IP header */
if (pbuf_header(p, IP_HLEN)) {
LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_LEVEL_SERIOUS, ("ip_output: not enough room for IP header in pbuf\n"));
IP_STATS_INC(ip.err);
snmp_inc_ipoutdiscards();
return ERR_BUF;
}
iphdr = (struct ip_hdr *)p->payload;
LWIP_ASSERT("check that first pbuf can hold struct ip_hdr",
(p->len >= sizeof(struct ip_hdr)));
IPH_TTL_SET(iphdr, ttl);
IPH_PROTO_SET(iphdr, proto);
#if CHECKSUM_GEN_IP_INLINE
chk_sum += LWIP_MAKE_U16(proto, ttl);
#endif /* CHECKSUM_GEN_IP_INLINE */
/* dest cannot be NULL here */
ip_addr_copy(iphdr->dest, *dest);
#if CHECKSUM_GEN_IP_INLINE
chk_sum += ip4_addr_get_u32(&iphdr->dest) & 0xFFFF;
chk_sum += ip4_addr_get_u32(&iphdr->dest) >> 16;
#endif /* CHECKSUM_GEN_IP_INLINE */
IPH_VHL_SET(iphdr, 4, ip_hlen / 4);
IPH_TOS_SET(iphdr, tos);
#if CHECKSUM_GEN_IP_INLINE
chk_sum += LWIP_MAKE_U16(tos, iphdr->_v_hl);
#endif /* CHECKSUM_GEN_IP_INLINE */
IPH_LEN_SET(iphdr, htons(p->tot_len));
#if CHECKSUM_GEN_IP_INLINE
chk_sum += iphdr->_len;
#endif /* CHECKSUM_GEN_IP_INLINE */
IPH_OFFSET_SET(iphdr, 0);
IPH_ID_SET(iphdr, htons(ip_id));
#if CHECKSUM_GEN_IP_INLINE
chk_sum += iphdr->_id;
#endif /* CHECKSUM_GEN_IP_INLINE */
++ip_id;
if (ip_addr_isany(src)) {
ip_addr_copy(iphdr->src, netif->ip_addr);
} else {
/* src cannot be NULL here */
ip_addr_copy(iphdr->src, *src);
}
#if CHECKSUM_GEN_IP_INLINE
chk_sum += ip4_addr_get_u32(&iphdr->src) & 0xFFFF;
chk_sum += ip4_addr_get_u32(&iphdr->src) >> 16;
chk_sum = (chk_sum >> 16) + (chk_sum & 0xFFFF);
chk_sum = (chk_sum >> 16) + chk_sum;
chk_sum = ~chk_sum;
iphdr->_chksum = chk_sum; /* network order */
#else /* CHECKSUM_GEN_IP_INLINE */
IPH_CHKSUM_SET(iphdr, 0);
#if CHECKSUM_GEN_IP
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, ip_hlen));
#endif
#endif /* CHECKSUM_GEN_IP_INLINE */
} else {
/* IP header already included in p */
iphdr = (struct ip_hdr *)p->payload;
ip_addr_copy(dest_addr, iphdr->dest);
dest = &dest_addr;
}
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);
#if ENABLE_LOOPBACK
if (ip_addr_cmp(dest, &netif->ip_addr)) {
/* Packet to self, enqueue it for loopback */
LWIP_DEBUGF(IP_DEBUG, ("netif_loop_output()"));
return netif_loop_output(netif, p, dest);
}
#if LWIP_IGMP
if ((p->flags & PBUF_FLAG_MCASTLOOP) != 0) {
netif_loop_output(netif, p, dest);
}
#endif /* LWIP_IGMP */
#endif /* ENABLE_LOOPBACK */
#if IP_FRAG
/* don't fragment if interface has mtu set to 0 [loopif] */
if (netif->mtu && (p->tot_len > netif->mtu)) {
return ip_frag(p, netif, dest);
}
#endif /* IP_FRAG */
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.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == IP_HDRINCL, p already includes an IP
header and p->payload points to that IP header)
* @param src the source IP address to send from (if src == IP_ADDR_ANY, the
* IP address of the netif used to send is used as source address)
* @param dest the destination IP address to send the packet to
* @param ttl the TTL value to be set in the IP header
* @param tos the TOS value to be set in the IP header
* @param proto the PROTOCOL to be set in the IP header
*
* @return ERR_RTE if no route is found
* see ip_output_if() for more return values
*/
err_t
ip_output(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
u8_t ttl, u8_t tos, u8_t proto)
{
struct netif *netif;
/* pbufs passed to IP must have a ref-count of 1 as their payload pointer
gets altered as the packet is passed down the stack */
LWIP_ASSERT("p->ref == 1", p->ref == 1);
if ((netif = ip_route(dest)) == NULL) {
LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
IP_STATS_INC(ip.rterr);
return ERR_RTE;
}
return ip_output_if(p, src, dest, ttl, tos, proto, netif);
}
#if LWIP_NETIF_HWADDRHINT
/** Like ip_output, but takes and addr_hint pointer that is passed on to netif->addr_hint
* before calling ip_output_if.
*
* @param p the packet to send (p->payload points to the data, e.g. next
protocol header; if dest == IP_HDRINCL, p already includes an IP
header and p->payload points to that IP header)
* @param src the source IP address to send from (if src == IP_ADDR_ANY, the
* IP address of the netif used to send is used as source address)
* @param dest the destination IP address to send the packet to
* @param ttl the TTL value to be set in the IP header
* @param tos the TOS value to be set in the IP header
* @param proto the PROTOCOL to be set in the IP header
* @param addr_hint address hint pointer set to netif->addr_hint before
* calling ip_output_if()
*
* @return ERR_RTE if no route is found
* see ip_output_if() for more return values
*/
err_t
ip_output_hinted(struct pbuf *p, ip_addr_t *src, ip_addr_t *dest,
u8_t ttl, u8_t tos, u8_t proto, u8_t *addr_hint)
{
struct netif *netif;
err_t err;
/* pbufs passed to IP must have a ref-count of 1 as their payload pointer
gets altered as the packet is passed down the stack */
LWIP_ASSERT("p->ref == 1", p->ref == 1);
if ((netif = ip_route(dest)) == NULL) {
LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ip4_addr1_16(dest), ip4_addr2_16(dest), ip4_addr3_16(dest), ip4_addr4_16(dest)));
IP_STATS_INC(ip.rterr);
return ERR_RTE;
}
NETIF_SET_HWADDRHINT(netif, addr_hint);
err = ip_output_if(p, src, dest, ttl, tos, proto, netif);
NETIF_SET_HWADDRHINT(netif, NULL);
return err;
}
#endif /* LWIP_NETIF_HWADDRHINT*/
#if IP_DEBUG
/* Print an IP header by using LWIP_DEBUGF
* @param p an IP packet, p->payload pointing to the IP header
*/
void
ip_debug_print(struct pbuf *p)
{
struct ip_hdr *iphdr = (struct ip_hdr *)p->payload;
LWIP_DEBUGF(IP_DEBUG, ("IP header:\n"));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("|%2"S16_F" |%2"S16_F" | 0x%02"X16_F" | %5"U16_F" | (v, hl, tos, len)\n",
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_16(&iphdr->src),
ip4_addr2_16(&iphdr->src),
ip4_addr3_16(&iphdr->src),
ip4_addr4_16(&iphdr->src)));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
LWIP_DEBUGF(IP_DEBUG, ("| %3"U16_F" | %3"U16_F" | %3"U16_F" | %3"U16_F" | (dest)\n",
ip4_addr1_16(&iphdr->dest),
ip4_addr2_16(&iphdr->dest),
ip4_addr3_16(&iphdr->dest),
ip4_addr4_16(&iphdr->dest)));
LWIP_DEBUGF(IP_DEBUG, ("+-------------------------------+\n"));
}
#endif /* IP_DEBUG */

312
ext/lwip/src/core/ipv4/ip_addr.c Normal file
View File

@@ -0,0 +1,312 @@
/**
* @file
* This is the IPv4 address tools implementation.
*
*/
/*
* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* This file is part of the lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/opt.h"
#include "lwip/ip_addr.h"
#include "lwip/netif.h"
/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */
const ip_addr_t ip_addr_any = { IPADDR_ANY };
const ip_addr_t ip_addr_broadcast = { IPADDR_BROADCAST };
/**
* Determine if an address is a broadcast address on a network interface
*
* @param addr address to be checked
* @param netif the network interface against which the address is checked
* @return returns non-zero if the address is a broadcast address
*/
u8_t
ip4_addr_isbroadcast(u32_t addr, const struct netif *netif)
{
ip_addr_t ipaddr;
ip4_addr_set_u32(&ipaddr, addr);
/* all ones (broadcast) or all zeroes (old skool broadcast) */
if ((~addr == IPADDR_ANY) ||
(addr == IPADDR_ANY)) {
return 1;
/* no broadcast support on this network interface? */
} else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) {
/* the given address cannot be a broadcast address
* nor can we check against any broadcast addresses */
return 0;
/* address matches network interface address exactly? => no broadcast */
} else if (addr == ip4_addr_get_u32(&netif->ip_addr)) {
return 0;
/* on the same (sub) network... */
} else if (ip_addr_netcmp(&ipaddr, &(netif->ip_addr), &(netif->netmask))
/* ...and host identifier bits are all ones? =>... */
&& ((addr & ~ip4_addr_get_u32(&netif->netmask)) ==
(IPADDR_BROADCAST & ~ip4_addr_get_u32(&netif->netmask)))) {
/* => network broadcast address */
return 1;
} else {
return 0;
}
}
/** Checks if a netmask is valid (starting with ones, then only zeros)
*
* @param netmask the IPv4 netmask to check (in network byte order!)
* @return 1 if the netmask is valid, 0 if it is not
*/
u8_t
ip4_addr_netmask_valid(u32_t netmask)
{
u32_t mask;
u32_t nm_hostorder = lwip_htonl(netmask);
/* first, check for the first zero */
for (mask = 1UL << 31 ; mask != 0; mask >>= 1) {
if ((nm_hostorder & mask) == 0) {
break;
}
}
/* then check that there is no one */
for (; mask != 0; mask >>= 1) {
if ((nm_hostorder & mask) != 0) {
/* there is a one after the first zero -> invalid */
return 0;
}
}
/* no one after the first zero -> valid */
return 1;
}
/* Here for now until needed in other places in lwIP */
#ifndef isprint
#define in_range(c, lo, up) ((u8_t)c >= lo && (u8_t)c <= up)
#define isprint(c) in_range(c, 0x20, 0x7f)
#define isdigit(c) in_range(c, '0', '9')
#define isxdigit(c) (isdigit(c) || in_range(c, 'a', 'f') || in_range(c, 'A', 'F'))
#define islower(c) in_range(c, 'a', 'z')
#define isspace(c) (c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v')
#endif
/**
* Ascii internet address interpretation routine.
* The value returned is in network order.
*
* @param cp IP address in ascii represenation (e.g. "127.0.0.1")
* @return ip address in network order
*/
u32_t
ipaddr_addr(const char *cp)
{
ip_addr_t val;
if (ipaddr_aton(cp, &val)) {
return ip4_addr_get_u32(&val);
}
return (IPADDR_NONE);
}
/**
* Check whether "cp" is a valid ascii representation
* of an Internet address and convert to a binary address.
* Returns 1 if the address is valid, 0 if not.
* This replaces inet_addr, the return value from which
* cannot distinguish between failure and a local broadcast address.
*
* @param cp IP address in ascii represenation (e.g. "127.0.0.1")
* @param addr pointer to which to save the ip address in network order
* @return 1 if cp could be converted to addr, 0 on failure
*/
int
ipaddr_aton(const char *cp, ip_addr_t *addr)
{
u32_t val;
u8_t base;
char c;
u32_t parts[4];
u32_t *pp = parts;
c = *cp;
for (;;) {
/*
* Collect number up to ``.''.
* Values are specified as for C:
* 0x=hex, 0=octal, 1-9=decimal.
*/
if (!isdigit(c))
return (0);
val = 0;
base = 10;
if (c == '0') {
c = *++cp;
if (c == 'x' || c == 'X') {
base = 16;
c = *++cp;
} else
base = 8;
}
for (;;) {
if (isdigit(c)) {
val = (val * base) + (int)(c - '0');
c = *++cp;
} else if (base == 16 && isxdigit(c)) {
val = (val << 4) | (int)(c + 10 - (islower(c) ? 'a' : 'A'));
c = *++cp;
} else
break;
}
if (c == '.') {
/*
* Internet format:
* a.b.c.d
* a.b.c (with c treated as 16 bits)
* a.b (with b treated as 24 bits)
*/
if (pp >= parts + 3) {
return (0);
}
*pp++ = val;
c = *++cp;
} else
break;
}
/*
* Check for trailing characters.
*/
if (c != '\0' && !isspace(c)) {
return (0);
}
/*
* Concoct the address according to
* the number of parts specified.
*/
switch (pp - parts + 1) {
case 0:
return (0); /* initial nondigit */
case 1: /* a -- 32 bits */
break;
case 2: /* a.b -- 8.24 bits */
if (val > 0xffffffUL) {
return (0);
}
val |= parts[0] << 24;
break;
case 3: /* a.b.c -- 8.8.16 bits */
if (val > 0xffff) {
return (0);
}
val |= (parts[0] << 24) | (parts[1] << 16);
break;
case 4: /* a.b.c.d -- 8.8.8.8 bits */
if (val > 0xff) {
return (0);
}
val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
break;
default:
LWIP_ASSERT("unhandled", 0);
break;
}
if (addr) {
ip4_addr_set_u32(addr, htonl(val));
}
return (1);
}
/**
* Convert numeric IP address into decimal dotted ASCII representation.
* returns ptr to static buffer; not reentrant!
*
* @param addr ip address in network order to convert
* @return pointer to a global static (!) buffer that holds the ASCII
* represenation of addr
*/
char *
ipaddr_ntoa(const ip_addr_t *addr)
{
static char str[16];
return ipaddr_ntoa_r(addr, str, 16);
}
/**
* Same as ipaddr_ntoa, but reentrant since a user-supplied buffer is used.
*
* @param addr ip address in network order to convert
* @param buf target buffer where the string is stored
* @param buflen length of buf
* @return either pointer to buf which now holds the ASCII
* representation of addr or NULL if buf was too small
*/
char *ipaddr_ntoa_r(const ip_addr_t *addr, char *buf, int buflen)
{
u32_t s_addr;
char inv[3];
char *rp;
u8_t *ap;
u8_t rem;
u8_t n;
u8_t i;
int len = 0;
s_addr = ip4_addr_get_u32(addr);
rp = buf;
ap = (u8_t *)&s_addr;
for(n = 0; n < 4; n++) {
i = 0;
do {
rem = *ap % (u8_t)10;
*ap /= (u8_t)10;
inv[i++] = '0' + rem;
} while(*ap);
while(i--) {
if (len++ >= buflen) {
return NULL;
}
*rp++ = inv[i];
}
if (len++ >= buflen) {
return NULL;
}
*rp++ = '.';
ap++;
}
*--rp = 0;
return buf;
}

863
ext/lwip/src/core/ipv4/ip_frag.c Normal file
View File

@@ -0,0 +1,863 @@
/**
* @file
* This is the IPv4 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>
* Simon Goldschmidt
* original reassembly code by Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/opt.h"
#include "lwip/ip_frag.h"
#include "lwip/def.h"
#include "lwip/inet_chksum.h"
#include "lwip/netif.h"
#include "lwip/snmp.h"
#include "lwip/stats.h"
#include "lwip/icmp.h"
#include <string.h>
#if IP_REASSEMBLY
/**
* The IP reassembly code currently has the following limitations:
* - IP header options are not supported
* - fragments must not overlap (e.g. due to different routes),
* currently, overlapping or duplicate fragments are thrown away
* if IP_REASS_CHECK_OVERLAP=1 (the default)!
*
* @todo: work with IP header options
*/
/** Setting this to 0, you can turn off checking the fragments for overlapping
* regions. The code gets a little smaller. Only use this if you know that
* overlapping won't occur on your network! */
#ifndef IP_REASS_CHECK_OVERLAP
#define IP_REASS_CHECK_OVERLAP 1
#endif /* IP_REASS_CHECK_OVERLAP */
/** Set to 0 to prevent freeing the oldest datagram when the reassembly buffer is
* full (IP_REASS_MAX_PBUFS pbufs are enqueued). The code gets a little smaller.
* Datagrams will be freed by timeout only. Especially useful when MEMP_NUM_REASSDATA
* is set to 1, so one datagram can be reassembled at a time, only. */
#ifndef IP_REASS_FREE_OLDEST
#define IP_REASS_FREE_OLDEST 1
#endif /* IP_REASS_FREE_OLDEST */
#define IP_REASS_FLAG_LASTFRAG 0x01
/** This is a helper struct which holds the starting
* offset and the ending offset of this fragment to
* easily chain the fragments.
* It has the same packing requirements as the IP header, since it replaces
* the IP header in memory in incoming fragments (after copying it) to keep
* track of the various fragments. (-> If the IP header doesn't need packing,
* this struct doesn't need packing, too.)
*/
#ifdef PACK_STRUCT_USE_INCLUDES
# include "arch/bpstruct.h"
#endif
PACK_STRUCT_BEGIN
struct ip_reass_helper {
PACK_STRUCT_FIELD(struct pbuf *next_pbuf);
PACK_STRUCT_FIELD(u16_t start);
PACK_STRUCT_FIELD(u16_t end);
} PACK_STRUCT_STRUCT;
PACK_STRUCT_END
#ifdef PACK_STRUCT_USE_INCLUDES
# include "arch/epstruct.h"
#endif
#define IP_ADDRESSES_AND_ID_MATCH(iphdrA, iphdrB) \
(ip_addr_cmp(&(iphdrA)->src, &(iphdrB)->src) && \
ip_addr_cmp(&(iphdrA)->dest, &(iphdrB)->dest) && \
IPH_ID(iphdrA) == IPH_ID(iphdrB)) ? 1 : 0
/* global variables */
static struct ip_reassdata *reassdatagrams;
static u16_t ip_reass_pbufcount;
/* function prototypes */
static void ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
static int ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev);
/**
* Reassembly timer base function
* for both NO_SYS == 0 and 1 (!).
*
* Should be called every 1000 msec (defined by IP_TMR_INTERVAL).
*/
void
ip_reass_tmr(void)
{
struct ip_reassdata *r, *prev = NULL;
r = reassdatagrams;
while (r != NULL) {
/* Decrement the timer. Once it reaches 0,
* clean up the incomplete fragment assembly */
if (r->timer > 0) {
r->timer--;
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer dec %"U16_F"\n",(u16_t)r->timer));
prev = r;
r = r->next;
} else {
/* reassembly timed out */
struct ip_reassdata *tmp;
LWIP_DEBUGF(IP_REASS_DEBUG, ("ip_reass_tmr: timer timed out\n"));
tmp = r;
/* get the next pointer before freeing */
r = r->next;
/* free the helper struct and all enqueued pbufs */
ip_reass_free_complete_datagram(tmp, prev);
}
}
}
/**
* Free a datagram (struct ip_reassdata) and all its pbufs.
* Updates the total count of enqueued pbufs (ip_reass_pbufcount),
* SNMP counters and sends an ICMP time exceeded packet.
*
* @param ipr datagram to free
* @param prev the previous datagram in the linked list
* @return the number of pbufs freed
*/
static int
ip_reass_free_complete_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
{
u16_t pbufs_freed = 0;
u8_t clen;
struct pbuf *p;
struct ip_reass_helper *iprh;
LWIP_ASSERT("prev != ipr", prev != ipr);
if (prev != NULL) {
LWIP_ASSERT("prev->next == ipr", prev->next == ipr);
}
snmp_inc_ipreasmfails();
#if LWIP_ICMP
iprh = (struct ip_reass_helper *)ipr->p->payload;
if (iprh->start == 0) {
/* The first fragment was received, send ICMP time exceeded. */
/* First, de-queue the first pbuf from r->p. */
p = ipr->p;
ipr->p = iprh->next_pbuf;
/* Then, copy the original header into it. */
SMEMCPY(p->payload, &ipr->iphdr, IP_HLEN);
icmp_time_exceeded(p, ICMP_TE_FRAG);
clen = pbuf_clen(p);
LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
pbufs_freed += clen;
pbuf_free(p);
}
#endif /* LWIP_ICMP */
/* First, free all received pbufs. The individual pbufs need to be released
separately as they have not yet been chained */
p = ipr->p;
while (p != NULL) {
struct pbuf *pcur;
iprh = (struct ip_reass_helper *)p->payload;
pcur = p;
/* get the next pointer before freeing */
p = iprh->next_pbuf;
clen = pbuf_clen(pcur);
LWIP_ASSERT("pbufs_freed + clen <= 0xffff", pbufs_freed + clen <= 0xffff);
pbufs_freed += clen;
pbuf_free(pcur);
}
/* Then, unchain the struct ip_reassdata from the list and free it. */
ip_reass_dequeue_datagram(ipr, prev);
LWIP_ASSERT("ip_reass_pbufcount >= clen", ip_reass_pbufcount >= pbufs_freed);
ip_reass_pbufcount -= pbufs_freed;
return pbufs_freed;
}
#if IP_REASS_FREE_OLDEST
/**
* Free the oldest datagram to make room for enqueueing new fragments.
* The datagram 'fraghdr' belongs to is not freed!
*
* @param fraghdr IP header of the current fragment
* @param pbufs_needed number of pbufs needed to enqueue
* (used for freeing other datagrams if not enough space)
* @return the number of pbufs freed
*/
static int
ip_reass_remove_oldest_datagram(struct ip_hdr *fraghdr, int pbufs_needed)
{
/* @todo Can't we simply remove the last datagram in the
* linked list behind reassdatagrams?
*/
struct ip_reassdata *r, *oldest, *prev;
int pbufs_freed = 0, pbufs_freed_current;
int other_datagrams;
/* Free datagrams until being allowed to enqueue 'pbufs_needed' pbufs,
* but don't free the datagram that 'fraghdr' belongs to! */
do {
oldest = NULL;
prev = NULL;
other_datagrams = 0;
r = reassdatagrams;
while (r != NULL) {
if (!IP_ADDRESSES_AND_ID_MATCH(&r->iphdr, fraghdr)) {
/* Not the same datagram as fraghdr */
other_datagrams++;
if (oldest == NULL) {
oldest = r;
} else if (r->timer <= oldest->timer) {
/* older than the previous oldest */
oldest = r;
}
}
if (r->next != NULL) {
prev = r;
}
r = r->next;
}
if (oldest != NULL) {
pbufs_freed_current = ip_reass_free_complete_datagram(oldest, prev);
pbufs_freed += pbufs_freed_current;
}
} while ((pbufs_freed < pbufs_needed) && (other_datagrams > 1));
return pbufs_freed;
}
#endif /* IP_REASS_FREE_OLDEST */
/**
* Enqueues a new fragment into the fragment queue
* @param fraghdr points to the new fragments IP hdr
* @param clen number of pbufs needed to enqueue (used for freeing other datagrams if not enough space)
* @return A pointer to the queue location into which the fragment was enqueued
*/
static struct ip_reassdata*
ip_reass_enqueue_new_datagram(struct ip_hdr *fraghdr, int clen)
{
struct ip_reassdata* ipr;
/* No matching previous fragment found, allocate a new reassdata struct */
ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
if (ipr == NULL) {
#if IP_REASS_FREE_OLDEST
if (ip_reass_remove_oldest_datagram(fraghdr, clen) >= clen) {
ipr = (struct ip_reassdata *)memp_malloc(MEMP_REASSDATA);
}
if (ipr == NULL)
#endif /* IP_REASS_FREE_OLDEST */
{
IPFRAG_STATS_INC(ip_frag.memerr);
LWIP_DEBUGF(IP_REASS_DEBUG,("Failed to alloc reassdata struct\n"));
return NULL;
}
}
memset(ipr, 0, sizeof(struct ip_reassdata));
ipr->timer = IP_REASS_MAXAGE;
/* enqueue the new structure to the front of the list */
ipr->next = reassdatagrams;
reassdatagrams = ipr;
/* copy the ip header for later tests and input */
/* @todo: no ip options supported? */
SMEMCPY(&(ipr->iphdr), fraghdr, IP_HLEN);
return ipr;
}
/**
* Dequeues a datagram from the datagram queue. Doesn't deallocate the pbufs.
* @param ipr points to the queue entry to dequeue
*/
static void
ip_reass_dequeue_datagram(struct ip_reassdata *ipr, struct ip_reassdata *prev)
{
/* dequeue the reass struct */
if (reassdatagrams == ipr) {
/* it was the first in the list */
reassdatagrams = ipr->next;
} else {
/* it wasn't the first, so it must have a valid 'prev' */
LWIP_ASSERT("sanity check linked list", prev != NULL);
prev->next = ipr->next;
}
/* now we can free the ip_reass struct */
memp_free(MEMP_REASSDATA, ipr);
}
/**
* Chain a new pbuf into the pbuf list that composes the datagram. The pbuf list
* will grow over time as new pbufs are rx.
* Also checks that the datagram passes basic continuity checks (if the last
* fragment was received at least once).
* @param root_p points to the 'root' pbuf for the current datagram being assembled.
* @param new_p points to the pbuf for the current fragment
* @return 0 if invalid, >0 otherwise
*/
static int
ip_reass_chain_frag_into_datagram_and_validate(struct ip_reassdata *ipr, struct pbuf *new_p)
{
struct ip_reass_helper *iprh, *iprh_tmp, *iprh_prev=NULL;
struct pbuf *q;
u16_t offset,len;
struct ip_hdr *fraghdr;
int valid = 1;
/* Extract length and fragment offset from current fragment */
fraghdr = (struct ip_hdr*)new_p->payload;
len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
/* overwrite the fragment's ip header from the pbuf with our helper struct,
* and setup the embedded helper structure. */
/* make sure the struct ip_reass_helper fits into the IP header */
LWIP_ASSERT("sizeof(struct ip_reass_helper) <= IP_HLEN",
sizeof(struct ip_reass_helper) <= IP_HLEN);
iprh = (struct ip_reass_helper*)new_p->payload;
iprh->next_pbuf = NULL;
iprh->start = offset;
iprh->end = offset + len;
/* Iterate through until we either get to the end of the list (append),
* or we find on with a larger offset (insert). */
for (q = ipr->p; q != NULL;) {
iprh_tmp = (struct ip_reass_helper*)q->payload;
if (iprh->start < iprh_tmp->start) {
/* the new pbuf should be inserted before this */
iprh->next_pbuf = q;
if (iprh_prev != NULL) {
/* not the fragment with the lowest offset */
#if IP_REASS_CHECK_OVERLAP
if ((iprh->start < iprh_prev->end) || (iprh->end > iprh_tmp->start)) {
/* fragment overlaps with previous or following, throw away */
goto freepbuf;
}
#endif /* IP_REASS_CHECK_OVERLAP */
iprh_prev->next_pbuf = new_p;
} else {
/* fragment with the lowest offset */
ipr->p = new_p;
}
break;
} else if(iprh->start == iprh_tmp->start) {
/* received the same datagram twice: no need to keep the datagram */
goto freepbuf;
#if IP_REASS_CHECK_OVERLAP
} else if(iprh->start < iprh_tmp->end) {
/* overlap: no need to keep the new datagram */
goto freepbuf;
#endif /* IP_REASS_CHECK_OVERLAP */
} else {
/* Check if the fragments received so far have no wholes. */
if (iprh_prev != NULL) {
if (iprh_prev->end != iprh_tmp->start) {
/* There is a fragment missing between the current
* and the previous fragment */
valid = 0;
}
}
}
q = iprh_tmp->next_pbuf;
iprh_prev = iprh_tmp;
}
/* If q is NULL, then we made it to the end of the list. Determine what to do now */
if (q == NULL) {
if (iprh_prev != NULL) {
/* this is (for now), the fragment with the highest offset:
* chain it to the last fragment */
#if IP_REASS_CHECK_OVERLAP
LWIP_ASSERT("check fragments don't overlap", iprh_prev->end <= iprh->start);
#endif /* IP_REASS_CHECK_OVERLAP */
iprh_prev->next_pbuf = new_p;
if (iprh_prev->end != iprh->start) {
valid = 0;
}
} else {
#if IP_REASS_CHECK_OVERLAP
LWIP_ASSERT("no previous fragment, this must be the first fragment!",
ipr->p == NULL);
#endif /* IP_REASS_CHECK_OVERLAP */
/* this is the first fragment we ever received for this ip datagram */
ipr->p = new_p;
}
}
/* At this point, the validation part begins: */
/* If we already received the last fragment */
if ((ipr->flags & IP_REASS_FLAG_LASTFRAG) != 0) {
/* and had no wholes so far */
if (valid) {
/* then check if the rest of the fragments is here */
/* Check if the queue starts with the first datagram */
if (((struct ip_reass_helper*)ipr->p->payload)->start != 0) {
valid = 0;
} else {
/* and check that there are no wholes after this datagram */
iprh_prev = iprh;
q = iprh->next_pbuf;
while (q != NULL) {
iprh = (struct ip_reass_helper*)q->payload;
if (iprh_prev->end != iprh->start) {
valid = 0;
break;
}
iprh_prev = iprh;
q = iprh->next_pbuf;
}
/* if still valid, all fragments are received
* (because to the MF==0 already arrived */
if (valid) {
LWIP_ASSERT("sanity check", ipr->p != NULL);
LWIP_ASSERT("sanity check",
((struct ip_reass_helper*)ipr->p->payload) != iprh);
LWIP_ASSERT("validate_datagram:next_pbuf!=NULL",
iprh->next_pbuf == NULL);
LWIP_ASSERT("validate_datagram:datagram end!=datagram len",
iprh->end == ipr->datagram_len);
}
}
}
/* If valid is 0 here, there are some fragments missing in the middle
* (since MF == 0 has already arrived). Such datagrams simply time out if
* no more fragments are received... */
return valid;
}
/* If we come here, not all fragments were received, yet! */
return 0; /* not yet valid! */
#if IP_REASS_CHECK_OVERLAP
freepbuf:
ip_reass_pbufcount -= pbuf_clen(new_p);
pbuf_free(new_p);
return 0;
#endif /* IP_REASS_CHECK_OVERLAP */
}
/**
* 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 *r;
struct ip_hdr *fraghdr;
struct ip_reassdata *ipr;
struct ip_reass_helper *iprh;
u16_t offset, len;
u8_t clen;
struct ip_reassdata *ipr_prev = NULL;
IPFRAG_STATS_INC(ip_frag.recv);
snmp_inc_ipreasmreqds();
fraghdr = (struct ip_hdr*)p->payload;
if ((IPH_HL(fraghdr) * 4) != IP_HLEN) {
LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: IP options currently not supported!\n"));
IPFRAG_STATS_INC(ip_frag.err);
goto nullreturn;
}
offset = (ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) * 8;
len = ntohs(IPH_LEN(fraghdr)) - IPH_HL(fraghdr) * 4;
/* Check if we are allowed to enqueue more datagrams. */
clen = pbuf_clen(p);
if ((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS) {
#if IP_REASS_FREE_OLDEST
if (!ip_reass_remove_oldest_datagram(fraghdr, clen) ||
((ip_reass_pbufcount + clen) > IP_REASS_MAX_PBUFS))
#endif /* IP_REASS_FREE_OLDEST */
{
/* No datagram could be freed and still too many pbufs enqueued */
LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: Overflow condition: pbufct=%d, clen=%d, MAX=%d\n",
ip_reass_pbufcount, clen, IP_REASS_MAX_PBUFS));
IPFRAG_STATS_INC(ip_frag.memerr);
/* @todo: send ICMP time exceeded here? */
/* drop this pbuf */
goto nullreturn;
}
}
/* Look for the datagram the fragment belongs to in the current datagram queue,
* remembering the previous in the queue for later dequeueing. */
for (ipr = reassdatagrams; ipr != NULL; ipr = ipr->next) {
/* Check if the incoming fragment matches the one currently present
in the reassembly buffer. If so, we proceed with copying the
fragment into the buffer. */
if (IP_ADDRESSES_AND_ID_MATCH(&ipr->iphdr, 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);
break;
}
ipr_prev = ipr;
}
if (ipr == NULL) {
/* Enqueue a new datagram into the datagram queue */
ipr = ip_reass_enqueue_new_datagram(fraghdr, clen);
/* Bail if unable to enqueue */
if(ipr == NULL) {
goto nullreturn;
}
} else {
if (((ntohs(IPH_OFFSET(fraghdr)) & IP_OFFMASK) == 0) &&
((ntohs(IPH_OFFSET(&ipr->iphdr)) & IP_OFFMASK) != 0)) {
/* ipr->iphdr is not the header from the first fragment, but fraghdr is
* -> copy fraghdr into ipr->iphdr since we want to have the header
* of the first fragment (for ICMP time exceeded and later, for copying
* all options, if supported)*/
SMEMCPY(&ipr->iphdr, fraghdr, IP_HLEN);
}
}
/* Track the current number of pbufs current 'in-flight', in order to limit
the number of fragments that may be enqueued at any one time */
ip_reass_pbufcount += clen;
/* At this point, we have either created a new entry or pointing
* to an existing one */
/* check for 'no more fragments', and update queue entry*/
if ((IPH_OFFSET(fraghdr) & PP_NTOHS(IP_MF)) == 0) {
ipr->flags |= IP_REASS_FLAG_LASTFRAG;
ipr->datagram_len = offset + len;
LWIP_DEBUGF(IP_REASS_DEBUG,
("ip_reass: last fragment seen, total len %"S16_F"\n",
ipr->datagram_len));
}
/* find the right place to insert this pbuf */
/* @todo: trim pbufs if fragments are overlapping */
if (ip_reass_chain_frag_into_datagram_and_validate(ipr, p)) {
/* the totally last fragment (flag more fragments = 0) was received at least
* once AND all fragments are received */
ipr->datagram_len += IP_HLEN;
/* save the second pbuf before copying the header over the pointer */
r = ((struct ip_reass_helper*)ipr->p->payload)->next_pbuf;
/* copy the original ip header back to the first pbuf */
fraghdr = (struct ip_hdr*)(ipr->p->payload);
SMEMCPY(fraghdr, &ipr->iphdr, IP_HLEN);
IPH_LEN_SET(fraghdr, htons(ipr->datagram_len));
IPH_OFFSET_SET(fraghdr, 0);
IPH_CHKSUM_SET(fraghdr, 0);
/* @todo: do we need to set calculate the correct checksum? */
IPH_CHKSUM_SET(fraghdr, inet_chksum(fraghdr, IP_HLEN));
p = ipr->p;
/* chain together the pbufs contained within the reass_data list. */
while(r != NULL) {
iprh = (struct ip_reass_helper*)r->payload;
/* hide the ip header for every succeding fragment */
pbuf_header(r, -IP_HLEN);
pbuf_cat(p, r);
r = iprh->next_pbuf;
}
/* release the sources allocate for the fragment queue entry */
ip_reass_dequeue_datagram(ipr, ipr_prev);
/* and adjust the number of pbufs currently queued for reassembly. */
ip_reass_pbufcount -= pbuf_clen(p);
/* Return the pbuf chain */
return p;
}
/* the datagram is not (yet?) reassembled completely */
LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass_pbufcount: %d out\n", ip_reass_pbufcount));
return NULL;
nullreturn:
LWIP_DEBUGF(IP_REASS_DEBUG,("ip_reass: nullreturn\n"));
IPFRAG_STATS_INC(ip_frag.drop);
pbuf_free(p);
return NULL;
}
#endif /* IP_REASSEMBLY */
#if IP_FRAG
#if IP_FRAG_USES_STATIC_BUF
static u8_t buf[LWIP_MEM_ALIGN_SIZE(IP_FRAG_MAX_MTU + MEM_ALIGNMENT - 1)];
#else /* IP_FRAG_USES_STATIC_BUF */
#if !LWIP_NETIF_TX_SINGLE_PBUF
/** Allocate a new struct pbuf_custom_ref */
static struct pbuf_custom_ref*
ip_frag_alloc_pbuf_custom_ref(void)
{
return (struct pbuf_custom_ref*)memp_malloc(MEMP_FRAG_PBUF);
}
/** Free a struct pbuf_custom_ref */
static void
ip_frag_free_pbuf_custom_ref(struct pbuf_custom_ref* p)
{
LWIP_ASSERT("p != NULL", p != NULL);
memp_free(MEMP_FRAG_PBUF, p);
}
/** Free-callback function to free a 'struct pbuf_custom_ref', called by
* pbuf_free. */
static void
ipfrag_free_pbuf_custom(struct pbuf *p)
{
struct pbuf_custom_ref *pcr = (struct pbuf_custom_ref*)p;
LWIP_ASSERT("pcr != NULL", pcr != NULL);
LWIP_ASSERT("pcr == p", (void*)pcr == (void*)p);
if (pcr->original != NULL) {
pbuf_free(pcr->original);
}
ip_frag_free_pbuf_custom_ref(pcr);
}
#endif /* !LWIP_NETIF_TX_SINGLE_PBUF */
#endif /* IP_FRAG_USES_STATIC_BUF */
/**
* 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_REF) or
* point PBUF_REFs into p (depending on IP_FRAG_USES_STATIC_BUF).
*
* @param p ip packet to send
* @param netif the netif on which to send
* @param dest destination ip address to which to send
*
* @return ERR_OK if sent successfully, err_t otherwise
*/
err_t
ip_frag(struct pbuf *p, struct netif *netif, ip_addr_t *dest)
{
struct pbuf *rambuf;
#if IP_FRAG_USES_STATIC_BUF
struct pbuf *header;
#else
#if !LWIP_NETIF_TX_SINGLE_PBUF
struct pbuf *newpbuf;
#endif
struct ip_hdr *original_iphdr;
#endif
struct ip_hdr *iphdr;
u16_t nfb;
u16_t left, cop;
u16_t mtu = netif->mtu;
u16_t ofo, omf;
u16_t last;
u16_t poff = IP_HLEN;
u16_t tmp;
#if !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF
u16_t newpbuflen = 0;
u16_t left_to_copy;
#endif
/* Get a RAM based MTU sized pbuf */
#if IP_FRAG_USES_STATIC_BUF
/* When using a static buffer, we use a PBUF_REF, which we will
* use to reference the packet (without link header).
* Layer and length is irrelevant.
*/
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 = LWIP_MEM_ALIGN((void *)buf);
/* Copy the IP header in it */
iphdr = (struct ip_hdr *)rambuf->payload;
SMEMCPY(iphdr, p->payload, IP_HLEN);
#else /* IP_FRAG_USES_STATIC_BUF */
original_iphdr = (struct ip_hdr *)p->payload;
iphdr = original_iphdr;
#endif /* IP_FRAG_USES_STATIC_BUF */
/* Save original offset */
tmp = ntohs(IPH_OFFSET(iphdr));
ofo = tmp & IP_OFFMASK;
omf = tmp & IP_MF;
left = p->tot_len - IP_HLEN;
nfb = (mtu - IP_HLEN) / 8;
while (left) {
last = (left <= mtu - IP_HLEN);
/* Set new offset and MF flag */
tmp = omf | (IP_OFFMASK & (ofo));
if (!last) {
tmp = tmp | IP_MF;
}
/* Fill this fragment */
cop = last ? left : nfb * 8;
#if IP_FRAG_USES_STATIC_BUF
poff += pbuf_copy_partial(p, (u8_t*)iphdr + IP_HLEN, cop, poff);
#else /* IP_FRAG_USES_STATIC_BUF */
#if LWIP_NETIF_TX_SINGLE_PBUF
rambuf = pbuf_alloc(PBUF_IP, cop, PBUF_RAM);
if (rambuf == NULL) {
return ERR_MEM;
}
LWIP_ASSERT("this needs a pbuf in one piece!",
(rambuf->len == rambuf->tot_len) && (rambuf->next == NULL));
poff += pbuf_copy_partial(p, rambuf->payload, cop, poff);
/* make room for the IP header */
if(pbuf_header(rambuf, IP_HLEN)) {
pbuf_free(rambuf);
return ERR_MEM;
}
/* fill in the IP header */
SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
iphdr = rambuf->payload;
#else /* LWIP_NETIF_TX_SINGLE_PBUF */
/* When not using a static buffer, create a chain of pbufs.
* The first will be a PBUF_RAM holding the link and IP header.
* The rest will be PBUF_REFs mirroring the pbuf chain to be fragged,
* but limited to the size of an mtu.
*/
rambuf = pbuf_alloc(PBUF_LINK, IP_HLEN, PBUF_RAM);
if (rambuf == NULL) {
return ERR_MEM;
}
LWIP_ASSERT("this needs a pbuf in one piece!",
(p->len >= (IP_HLEN)));
SMEMCPY(rambuf->payload, original_iphdr, IP_HLEN);
iphdr = (struct ip_hdr *)rambuf->payload;
/* Can just adjust p directly for needed offset. */
p->payload = (u8_t *)p->payload + poff;
p->len -= poff;
left_to_copy = cop;
while (left_to_copy) {
struct pbuf_custom_ref *pcr;
newpbuflen = (left_to_copy < p->len) ? left_to_copy : p->len;
/* Is this pbuf already empty? */
if (!newpbuflen) {
p = p->next;
continue;
}
pcr = ip_frag_alloc_pbuf_custom_ref();
if (pcr == NULL) {
pbuf_free(rambuf);
return ERR_MEM;
}
/* Mirror this pbuf, although we might not need all of it. */
newpbuf = pbuf_alloced_custom(PBUF_RAW, newpbuflen, PBUF_REF, &pcr->pc, p->payload, newpbuflen);
if (newpbuf == NULL) {
ip_frag_free_pbuf_custom_ref(pcr);
pbuf_free(rambuf);
return ERR_MEM;
}
pbuf_ref(p);
pcr->original = p;
pcr->pc.custom_free_function = ipfrag_free_pbuf_custom;
/* Add it to end of rambuf's chain, but using pbuf_cat, not pbuf_chain
* so that it is removed when pbuf_dechain is later called on rambuf.
*/
pbuf_cat(rambuf, newpbuf);
left_to_copy -= newpbuflen;
if (left_to_copy) {
p = p->next;
}
}
poff = newpbuflen;
#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
#endif /* IP_FRAG_USES_STATIC_BUF */
/* Correct header */
IPH_OFFSET_SET(iphdr, htons(tmp));
IPH_LEN_SET(iphdr, htons(cop + IP_HLEN));
IPH_CHKSUM_SET(iphdr, 0);
IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
#if IP_FRAG_USES_STATIC_BUF
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;
}
#else /* IP_FRAG_USES_STATIC_BUF */
/* No need for separate header pbuf - we allowed room for it in rambuf
* when allocated.
*/
netif->output(netif, rambuf, dest);
IPFRAG_STATS_INC(ip_frag.xmit);
/* Unfortunately we can't reuse rambuf - the hardware may still be
* using the buffer. Instead we free it (and the ensuing chain) and
* recreate it next time round the loop. If we're lucky the hardware
* will have already sent the packet, the free will really free, and
* there will be zero memory penalty.
*/
pbuf_free(rambuf);
#endif /* IP_FRAG_USES_STATIC_BUF */
left -= cop;
ofo += nfb;
}
#if IP_FRAG_USES_STATIC_BUF
pbuf_free(rambuf);
#endif /* IP_FRAG_USES_STATIC_BUF */
snmp_inc_ipfragoks();
return ERR_OK;
}
#endif /* IP_FRAG */