ip6.c File Reference

#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/ip.h"
#include "lwip/inet.h"
#include "lwip/netif.h"
#include "lwip/icmp.h"
#include "lwip/udp.h"
#include "lwip/tcp_impl.h"
#include "lwip/stats.h"
#include "arch/perf.h"

Include dependency graph for ip6.c:

Go to the source code of this file.

Functions
void	ip_init (void)
struct netif *	ip_route (struct ip_addr *dest)
static void	ip_forward (struct pbuf *p, struct ip_hdr *iphdr)
void	ip_input (struct pbuf *p, struct netif *inp)
err_t	ip_output_if (struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, u8_t ttl, u8_t proto, struct netif *netif)
err_t	ip_output (struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, u8_t ttl, u8_t proto)

Function Documentation

ip_forward()

static void ip_forward ( struct pbuf *  p, struct ip_hdr *  iphdr  )

static

Definition at line 96 of file ip6.c.

{
  struct netif *netif;
 
  PERF_START;
 
  if ((netif = ip_route((struct ip_addr *)&(iphdr->dest))) == NULL) {
 
    LWIP_DEBUGF(IP_DEBUG, ("ip_input: no forwarding route found for "));
#if IP_DEBUG
    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
#endif /* IP_DEBUG */
    LWIP_DEBUGF(IP_DEBUG, ("\n"));
    pbuf_free(p);
    return;
  }
  /* Decrement TTL and send ICMP if ttl == 0. */
  if (--iphdr->hoplim == 0) {
#if LWIP_ICMP
    /* Don't send ICMP messages in response to ICMP messages */
    if (iphdr->nexthdr != IP_PROTO_ICMP) {
      icmp_time_exceeded(p, ICMP_TE_TTL);
    }
#endif /* LWIP_ICMP */
    pbuf_free(p);
    return;
  }
 
  /* Incremental update of the IP checksum. */
  /*  if (iphdr->chksum >= htons(0xffff - 0x100)) {
    iphdr->chksum += htons(0x100) + 1;
  } else {
    iphdr->chksum += htons(0x100);
    }*/
 
 
  LWIP_DEBUGF(IP_DEBUG, ("ip_forward: forwarding packet to "));
#if IP_DEBUG
  ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
#endif /* IP_DEBUG */
  LWIP_DEBUGF(IP_DEBUG, ("\n"));
 
  IP_STATS_INC(ip.fw);
  IP_STATS_INC(ip.xmit);
 
  PERF_STOP("ip_forward");
 
  netif->output(netif, p, (struct ip_addr *)&(iphdr->dest));
}

Referenced by ip_input().

ip_init()

void ip_init

(

void

)

Definition at line 63 of file ip6.c.

{
}

ip_input()

void ip_input	(	struct pbuf *	p,
		struct netif *	inp
	)

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.

Parameters

p	the received IP packet (p->payload points to IP header)
inp	the netif on which this packet was received

Returns

ERR_OK if the packet was processed (could return ERR_* if it wasn't processed, but currently always returns ERR_OK)

Definition at line 157 of file ip6.c.

                                            {
  struct ip_hdr *iphdr;
  struct netif *netif;
 
 
  PERF_START;
 
#if IP_DEBUG
  ip_debug_print(p);
#endif /* IP_DEBUG */
 
 
  IP_STATS_INC(ip.recv);
 
  /* identify the IP header */
  iphdr = p->payload;
 
 
  if (iphdr->v != 6) {
    LWIP_DEBUGF(IP_DEBUG, ("IP packet dropped due to bad version number\n"));
#if IP_DEBUG
    ip_debug_print(p);
#endif /* IP_DEBUG */
    pbuf_free(p);
    IP_STATS_INC(ip.err);
    IP_STATS_INC(ip.drop);
    return;
  }
 
  /* is this packet for us? */
  for(netif = netif_list; netif != NULL; netif = netif->next) {
#if IP_DEBUG
    LWIP_DEBUGF(IP_DEBUG, ("ip_input: iphdr->dest "));
    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
    LWIP_DEBUGF(IP_DEBUG, ("netif->ip_addr "));
    ip_addr_debug_print(IP_DEBUG, ((struct ip_addr *)&(iphdr->dest)));
    LWIP_DEBUGF(IP_DEBUG, ("\n"));
#endif /* IP_DEBUG */
    if (ip_addr_cmp(&(iphdr->dest), &(netif->ip_addr))) {
      break;
    }
  }
 
 
  if (netif == NULL) {
    /* packet not for us, route or discard */
#if IP_FORWARD
    ip_forward(p, iphdr);
#endif
    pbuf_free(p);
    return;
  }
 
  pbuf_realloc(p, IP_HLEN + ntohs(iphdr->len));
 
  /* send to upper layers */
#if IP_DEBUG
  /*  LWIP_DEBUGF("ip_input: \n");
  ip_debug_print(p);
  LWIP_DEBUGF("ip_input: p->len %"U16_F" p->tot_len %"U16_F"\n", p->len, p->tot_len);*/
#endif /* IP_DEBUG */
 
  if(pbuf_header(p, -IP_HLEN)) {
    LWIP_ASSERT("Can't move over header in packet", 0);
    return;
  }
 
  switch (iphdr->nexthdr) {
  case IP_PROTO_UDP:
    udp_input(p, inp);
    break;
  case IP_PROTO_TCP:
    tcp_input(p, inp);
    break;
#if LWIP_ICMP
  case IP_PROTO_ICMP:
    icmp_input(p, inp);
    break;
#endif /* LWIP_ICMP */
  default:
#if LWIP_ICMP
    /* send ICMP destination protocol unreachable */
    icmp_dest_unreach(p, ICMP_DUR_PROTO);
#endif /* LWIP_ICMP */
    pbuf_free(p);
    LWIP_DEBUGF(IP_DEBUG, ("Unsupported transport protocol %"U16_F"\n",
          iphdr->nexthdr));
 
    IP_STATS_INC(ip.proterr);
    IP_STATS_INC(ip.drop);
  }
  PERF_STOP("ip_input");
}

ip_output()

err_t ip_output	(	struct pbuf *	p,
		struct ip_addr *	src,
		struct ip_addr *	dest,
		u8_t	ttl,
		u8_t	proto
	)

Definition at line 317 of file ip6.c.

{
  struct netif *netif;
  if ((netif = ip_route(dest)) == NULL) {
    LWIP_DEBUGF(IP_DEBUG, ("ip_output: No route to 0x%"X32_F"\n", dest->addr));
    IP_STATS_INC(ip.rterr);
    return ERR_RTE;
  }
 
  return ip_output_if (p, src, dest, ttl, proto, netif);
}

ip_output_if()

err_t ip_output_if	(	struct pbuf *	p,
		struct ip_addr *	src,
		struct ip_addr *	dest,
		u8_t	ttl,
		u8_t	proto,
		struct netif *	netif
	)

Definition at line 260 of file ip6.c.

{
  struct ip_hdr *iphdr;
 
  PERF_START;
 
  LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
  if (pbuf_header(p, IP_HLEN)) {
    LWIP_DEBUGF(IP_DEBUG, ("ip_output: not enough room for IP header in pbuf\n"));
    IP_STATS_INC(ip.err);
 
    return ERR_BUF;
  }
  LWIP_DEBUGF(IP_DEBUG, ("len %"U16_F" tot_len %"U16_F"\n", p->len, p->tot_len));
 
  iphdr = p->payload;
 
 
  if (dest != IP_HDRINCL) {
    LWIP_DEBUGF(IP_DEBUG, ("!IP_HDRLINCL\n"));
    iphdr->hoplim = ttl;
    iphdr->nexthdr = proto;
    iphdr->len = htons(p->tot_len - IP_HLEN);
    ip_addr_set(&(iphdr->dest), dest);
 
    iphdr->v = 6;
 
    if (ip_addr_isany(src)) {
      ip_addr_set(&(iphdr->src), &(netif->ip_addr));
    } else {
      ip_addr_set(&(iphdr->src), src);
    }
 
  } else {
    dest = &(iphdr->dest);
  }
 
  IP_STATS_INC(ip.xmit);
 
  LWIP_DEBUGF(IP_DEBUG, ("ip_output_if: %c%c (len %"U16_F")\n", netif->name[0], netif->name[1], p->tot_len));
#if IP_DEBUG
  ip_debug_print(p);
#endif /* IP_DEBUG */
 
  PERF_STOP("ip_output_if");
  return netif->output(netif, p, dest);
}

Referenced by ip_output().

ip_route()

struct netif * ip_route

(

struct ip_addr *

dest

)

Definition at line 75 of file ip6.c.

{
  struct netif *netif;
 
  for(netif = netif_list; netif != NULL; netif = netif->next) {
    if (ip_addr_netcmp(dest, &(netif->ip_addr), &(netif->netmask))) {
      return netif;
    }
  }
 
  return netif_default;
}

Referenced by ip_forward(), and ip_output().