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/**
* @file
* Implementation of raw protocol PCBs for low-level handling of
* different types of protocols besides (or overriding) those
* already available in lwIP.\n
* See also @ref raw_raw
*
* @defgroup raw_raw RAW
* @ingroup callbackstyle_api
* Implementation of raw protocol PCBs for low-level handling of
* different types of protocols besides (or overriding) those
* already available in lwIP.\n
* @see @ref raw_api
*/
/*
* 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 LWIP_RAW /* don't build if not configured for use in lwipopts.h */
#include "lwip/def.h"
#include "lwip/memp.h"
#include "lwip/ip_addr.h"
#include "lwip/netif.h"
#include "lwip/raw.h"
#include "lwip/stats.h"
#include "lwip/ip6.h"
#include "lwip/ip6_addr.h"
#include "lwip/inet_chksum.h"
#include <string.h>
/** The list of RAW PCBs */
static struct raw_pcb *raw_pcbs;
static u8_t
raw_input_local_match(struct raw_pcb *pcb, u8_t broadcast)
{
LWIP_UNUSED_ARG(broadcast); /* in IPv6 only case */
/* check if PCB is bound to specific netif */
if ((pcb->netif_idx != NETIF_NO_INDEX) &&
(pcb->netif_idx != netif_get_index(ip_data.current_input_netif))) {
return 0;
}
#if LWIP_IPV4 && LWIP_IPV6
/* Dual-stack: PCBs listening to any IP type also listen to any IP address */
if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
#if IP_SOF_BROADCAST_RECV
if ((broadcast != 0) && !ip_get_option(pcb, SOF_BROADCAST)) {
return 0;
}
#endif /* IP_SOF_BROADCAST_RECV */
return 1;
}
#endif /* LWIP_IPV4 && LWIP_IPV6 */
/* Only need to check PCB if incoming IP version matches PCB IP version */
if (IP_ADDR_PCB_VERSION_MATCH_EXACT(pcb, ip_current_dest_addr())) {
#if LWIP_IPV4
/* Special case: IPv4 broadcast: receive all broadcasts
* Note: broadcast variable can only be 1 if it is an IPv4 broadcast */
if (broadcast != 0) {
#if IP_SOF_BROADCAST_RECV
if (ip_get_option(pcb, SOF_BROADCAST))
#endif /* IP_SOF_BROADCAST_RECV */
{
if (ip4_addr_isany(ip_2_ip4(&pcb->local_ip))) {
return 1;
}
}
} else
#endif /* LWIP_IPV4 */
/* Handle IPv4 and IPv6: catch all or exact match */
if (ip_addr_isany(&pcb->local_ip) ||
ip_addr_cmp(&pcb->local_ip, ip_current_dest_addr())) {
return 1;
}
}
return 0;
}
/**
* Determine if in incoming IP packet is covered by a RAW PCB
* and if so, pass it to a user-provided receive callback function.
*
* Given an incoming IP datagram (as a chain of pbufs) this function
* finds a corresponding RAW PCB and calls the corresponding receive
* callback function.
*
* @param p pbuf to be demultiplexed to a RAW PCB.
* @param inp network interface on which the datagram was received.
* @return - 1 if the packet has been eaten by a RAW PCB receive
* callback function. The caller MAY NOT not reference the
* packet any longer, and MAY NOT call pbuf_free().
* @return - 0 if packet is not eaten (pbuf is still referenced by the
* caller).
*
*/
u8_t
raw_input(struct pbuf *p, struct netif *inp)
{
struct raw_pcb *pcb, *prev;
s16_t proto;
u8_t eaten = 0;
u8_t broadcast = ip_addr_isbroadcast(ip_current_dest_addr(), ip_current_netif());
LWIP_UNUSED_ARG(inp);
#if LWIP_IPV6
#if LWIP_IPV4
if (IP_HDR_GET_VERSION(p->payload) == 6)
#endif /* LWIP_IPV4 */
{
struct ip6_hdr *ip6hdr = (struct ip6_hdr *)p->payload;
proto = IP6H_NEXTH(ip6hdr);
}
#if LWIP_IPV4
else
#endif /* LWIP_IPV4 */
#endif /* LWIP_IPV6 */
#if LWIP_IPV4
{
proto = IPH_PROTO((struct ip_hdr *)p->payload);
}
#endif /* LWIP_IPV4 */
prev = NULL;
pcb = raw_pcbs;
/* loop through all raw pcbs until the packet is eaten by one */
/* this allows multiple pcbs to match against the packet by design */
while ((eaten == 0) && (pcb != NULL)) {
if ((pcb->protocol == proto) && raw_input_local_match(pcb, broadcast) &&
(((pcb->flags & RAW_FLAGS_CONNECTED) == 0) ||
ip_addr_cmp(&pcb->remote_ip, ip_current_src_addr()))) {
/* receive callback function available? */
if (pcb->recv != NULL) {
#ifndef LWIP_NOASSERT
void *old_payload = p->payload;
#endif
/* the receive callback function did not eat the packet? */
eaten = pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr());
if (eaten != 0) {
/* receive function ate the packet */
p = NULL;
eaten = 1;
if (prev != NULL) {
/* move the pcb to the front of raw_pcbs so that is
found faster next time */
prev->next = pcb->next;
pcb->next = raw_pcbs;
raw_pcbs = pcb;
}
} else {
/* sanity-check that the receive callback did not alter the pbuf */
LWIP_ASSERT("raw pcb recv callback altered pbuf payload pointer without eating packet",
p->payload == old_payload);
}
}
/* no receive callback function was set for this raw PCB */
}
/* drop the packet */
prev = pcb;
pcb = pcb->next;
}
return eaten;
}
/**
* @ingroup raw_raw
* Bind a RAW PCB.
*
* @param pcb RAW PCB to be bound with a local address ipaddr.
* @param ipaddr local IP address to bind with. Use IP4_ADDR_ANY to
* bind to all local interfaces.
*
* @return lwIP error code.
* - ERR_OK. Successful. No error occurred.
* - ERR_USE. The specified IP address is already bound to by
* another RAW PCB.
*
* @see raw_disconnect()
*/
err_t
raw_bind(struct raw_pcb *pcb, const ip_addr_t *ipaddr)
{
if ((pcb == NULL) || (ipaddr == NULL)) {
return ERR_VAL;
}
ip_addr_set_ipaddr(&pcb->local_ip, ipaddr);
#if LWIP_IPV6 && LWIP_IPV6_SCOPES
/* If the given IP address should have a zone but doesn't, assign one now.
* This is legacy support: scope-aware callers should always provide properly
* zoned source addresses. */
if (IP_IS_V6(&pcb->local_ip) &&
ip6_addr_lacks_zone(ip_2_ip6(&pcb->local_ip), IP6_UNKNOWN)) {
ip6_addr_select_zone(ip_2_ip6(&pcb->local_ip), ip_2_ip6(&pcb->local_ip));
}
#endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */
return ERR_OK;
}
/**
* @ingroup raw_raw
* Bind an RAW PCB to a specific netif.
* After calling this function, all packets received via this PCB
* are guaranteed to have come in via the specified netif, and all
* outgoing packets will go out via the specified netif.
*
* @param pcb RAW PCB to be bound with netif.
* @param netif netif to bind to. Can be NULL.
*
* @see raw_disconnect()
*/
void
raw_bind_netif(struct raw_pcb *pcb, const struct netif *netif)
{
if (netif != NULL) {
pcb->netif_idx = netif_get_index(netif);
} else {
pcb->netif_idx = NETIF_NO_INDEX;
}
}
/**
* @ingroup raw_raw
* Connect an RAW PCB. This function is required by upper layers
* of lwip. Using the raw api you could use raw_sendto() instead
*
* This will associate the RAW PCB with the remote address.
*
* @param pcb RAW PCB to be connected with remote address ipaddr and port.
* @param ipaddr remote IP address to connect with.
*
* @return lwIP error code
*
* @see raw_disconnect() and raw_sendto()
*/
err_t
raw_connect(struct raw_pcb *pcb, const ip_addr_t *ipaddr)
{
if ((pcb == NULL) || (ipaddr == NULL)) {
return ERR_VAL;
}
ip_addr_set_ipaddr(&pcb->remote_ip, ipaddr);
#if LWIP_IPV6 && LWIP_IPV6_SCOPES
/* If the given IP address should have a zone but doesn't, assign one now,
* using the bound address to make a more informed decision when possible. */
if (IP_IS_V6(&pcb->remote_ip) &&
ip6_addr_lacks_zone(ip_2_ip6(&pcb->remote_ip), IP6_UNKNOWN)) {
ip6_addr_select_zone(ip_2_ip6(&pcb->remote_ip), ip_2_ip6(&pcb->local_ip));
}
#endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */
raw_set_flags(pcb, RAW_FLAGS_CONNECTED);
return ERR_OK;
}
/**
* @ingroup raw_raw
* Disconnect a RAW PCB.
*
* @param pcb the raw pcb to disconnect.
*/
void
raw_disconnect(struct raw_pcb *pcb)
{
/* reset remote address association */
#if LWIP_IPV4 && LWIP_IPV6
if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
ip_addr_copy(pcb->remote_ip, *IP_ANY_TYPE);
} else {
#endif
ip_addr_set_any(IP_IS_V6_VAL(pcb->remote_ip), &pcb->remote_ip);
#if LWIP_IPV4 && LWIP_IPV6
}
#endif
pcb->netif_idx = NETIF_NO_INDEX;
/* mark PCB as unconnected */
raw_clear_flags(pcb, RAW_FLAGS_CONNECTED);
}
/**
* @ingroup raw_raw
* Set the callback function for received packets that match the
* raw PCB's protocol and binding.
*
* The callback function MUST either
* - eat the packet by calling pbuf_free() and returning non-zero. The
* packet will not be passed to other raw PCBs or other protocol layers.
* - not free the packet, and return zero. The packet will be matched
* against further PCBs and/or forwarded to another protocol layers.
*/
void
raw_recv(struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg)
{
/* remember recv() callback and user data */
pcb->recv = recv;
pcb->recv_arg = recv_arg;
}
/**
* @ingroup raw_raw
* Send the raw IP packet to the given address. An IP header will be prepended
* to the packet, unless the RAW_FLAGS_HDRINCL flag is set on the PCB. In that
* case, the packet must include an IP header, which will then be sent as is.
*
* @param pcb the raw pcb which to send
* @param p the IP payload to send
* @param ipaddr the destination address of the IP packet
*
*/
err_t
raw_sendto(struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *ipaddr)
{
struct netif *netif;
const ip_addr_t *src_ip;
if ((pcb == NULL) || (ipaddr == NULL) || !IP_ADDR_PCB_VERSION_MATCH(pcb, ipaddr)) {
return ERR_VAL;
}
LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_sendto\n"));
if (pcb->netif_idx != NETIF_NO_INDEX) {
netif = netif_get_by_index(pcb->netif_idx);
} else {
#if LWIP_MULTICAST_TX_OPTIONS
netif = NULL;
if (ip_addr_ismulticast(ipaddr)) {
/* For multicast-destined packets, use the user-provided interface index to
* determine the outgoing interface, if an interface index is set and a
* matching netif can be found. Otherwise, fall back to regular routing. */
netif = netif_get_by_index(pcb->mcast_ifindex);
}
if (netif == NULL)
#endif /* LWIP_MULTICAST_TX_OPTIONS */
{
netif = ip_route(&pcb->local_ip, ipaddr);
}
}
if (netif == NULL) {
LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: No route to "));
ip_addr_debug_print(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ipaddr);
return ERR_RTE;
}
if (ip_addr_isany(&pcb->local_ip) || ip_addr_ismulticast(&pcb->local_ip)) {
/* use outgoing network interface IP address as source address */
src_ip = ip_netif_get_local_ip(netif, ipaddr);
#if LWIP_IPV6
if (src_ip == NULL) {
return ERR_RTE;
}
#endif /* LWIP_IPV6 */
} else {
/* use RAW PCB local IP address as source address */
src_ip = &pcb->local_ip;
}
return raw_sendto_if_src(pcb, p, ipaddr, netif, src_ip);
}
/**
* @ingroup raw_raw
* Send the raw IP packet to the given address, using a particular outgoing
* netif and source IP address. An IP header will be prepended to the packet,
* unless the RAW_FLAGS_HDRINCL flag is set on the PCB. In that case, the
* packet must include an IP header, which will then be sent as is.
*
* @param pcb RAW PCB used to send the data
* @param p chain of pbufs to be sent
* @param dst_ip destination IP address
* @param netif the netif used for sending
* @param src_ip source IP address
*/
err_t
raw_sendto_if_src(struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip,
struct netif *netif, const ip_addr_t *src_ip)
{
err_t err;
struct pbuf *q; /* q will be sent down the stack */
u16_t header_size;
u8_t ttl;
if ((pcb == NULL) || (dst_ip == NULL) || (netif == NULL) || (src_ip == NULL) ||
!IP_ADDR_PCB_VERSION_MATCH(pcb, src_ip) || !IP_ADDR_PCB_VERSION_MATCH(pcb, dst_ip)) {
return ERR_VAL;
}
header_size = (
#if LWIP_IPV4 && LWIP_IPV6
IP_IS_V6(dst_ip) ? IP6_HLEN : IP_HLEN);
#elif LWIP_IPV4
IP_HLEN);
#else
IP6_HLEN);
#endif
/* Handle the HDRINCL option as an exception: none of the code below applies
* to this case, and sending the packet needs to be done differently too. */
if (pcb->flags & RAW_FLAGS_HDRINCL) {
/* A full header *must* be present in the first pbuf of the chain, as the
* output routines may access its fields directly. */
if (p->len < header_size) {
return ERR_VAL;
}
/* @todo multicast loop support, if at all desired for this scenario.. */
NETIF_SET_HINTS(netif, &pcb->netif_hints);
err = ip_output_if_hdrincl(p, src_ip, dst_ip, netif);
NETIF_RESET_HINTS(netif);
return err;
}
/* packet too large to add an IP header without causing an overflow? */
if ((u16_t)(p->tot_len + header_size) < p->tot_len) {
return ERR_MEM;
}
/* not enough space to add an IP header to first pbuf in given p chain? */
if (pbuf_add_header(p, header_size)) {
/* allocate header in new pbuf */
q = pbuf_alloc(PBUF_IP, 0, PBUF_RAM);
/* new header pbuf could not be allocated? */
if (q == NULL) {
LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("raw_sendto: could not allocate header\n"));
return ERR_MEM;
}
if (p->tot_len != 0) {
/* chain header q in front of given pbuf p */
pbuf_chain(q, p);
}
/* { first pbuf q points to header pbuf } */
LWIP_DEBUGF(RAW_DEBUG, ("raw_sendto: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p));
} else {
/* first pbuf q equals given pbuf */
q = p;
if (pbuf_remove_header(q, header_size)) {
LWIP_ASSERT("Can't restore header we just removed!", 0);
return ERR_MEM;
}
}
#if IP_SOF_BROADCAST
if (IP_IS_V4(dst_ip)) {
/* broadcast filter? */
if (!ip_get_option(pcb, SOF_BROADCAST) && ip_addr_isbroadcast(dst_ip, netif)) {
LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb));
/* free any temporary header pbuf allocated by pbuf_header() */
if (q != p) {
pbuf_free(q);
}
return ERR_VAL;
}
}
#endif /* IP_SOF_BROADCAST */
/* Multicast Loop? */
#if LWIP_MULTICAST_TX_OPTIONS
if (((pcb->flags & RAW_FLAGS_MULTICAST_LOOP) != 0) && ip_addr_ismulticast(dst_ip)) {
q->flags |= PBUF_FLAG_MCASTLOOP;
}
#endif /* LWIP_MULTICAST_TX_OPTIONS */
#if LWIP_IPV6
/* If requested, based on the IPV6_CHECKSUM socket option per RFC3542,
compute the checksum and update the checksum in the payload. */
if (IP_IS_V6(dst_ip) && pcb->chksum_reqd) {
u16_t chksum = ip6_chksum_pseudo(p, pcb->protocol, p->tot_len, ip_2_ip6(src_ip), ip_2_ip6(dst_ip));
LWIP_ASSERT("Checksum must fit into first pbuf", p->len >= (pcb->chksum_offset + 2));
SMEMCPY(((u8_t *)p->payload) + pcb->chksum_offset, &chksum, sizeof(u16_t));
}
#endif
/* Determine TTL to use */
#if LWIP_MULTICAST_TX_OPTIONS
ttl = (ip_addr_ismulticast(dst_ip) ? raw_get_multicast_ttl(pcb) : pcb->ttl);
#else /* LWIP_MULTICAST_TX_OPTIONS */
ttl = pcb->ttl;
#endif /* LWIP_MULTICAST_TX_OPTIONS */
NETIF_SET_HINTS(netif, &pcb->netif_hints);
err = ip_output_if(q, src_ip, dst_ip, ttl, pcb->tos, pcb->protocol, netif);
NETIF_RESET_HINTS(netif);
/* did we chain a header earlier? */
if (q != p) {
/* free the header */
pbuf_free(q);
}
return err;
}
/**
* @ingroup raw_raw
* Send the raw IP packet to the address given by raw_connect()
*
* @param pcb the raw pcb which to send
* @param p the IP payload to send
*
*/
err_t
raw_send(struct raw_pcb *pcb, struct pbuf *p)
{
return raw_sendto(pcb, p, &pcb->remote_ip);
}
/**
* @ingroup raw_raw
* Remove an RAW PCB.
*
* @param pcb RAW PCB to be removed. The PCB is removed from the list of
* RAW PCB's and the data structure is freed from memory.
*
* @see raw_new()
*/
void
raw_remove(struct raw_pcb *pcb)
{
struct raw_pcb *pcb2;
/* pcb to be removed is first in list? */
if (raw_pcbs == pcb) {
/* make list start at 2nd pcb */
raw_pcbs = raw_pcbs->next;
/* pcb not 1st in list */
} else {
for (pcb2 = raw_pcbs; pcb2 != NULL; pcb2 = pcb2->next) {
/* find pcb in raw_pcbs list */
if (pcb2->next != NULL && pcb2->next == pcb) {
/* remove pcb from list */
pcb2->next = pcb->next;
break;
}
}
}
memp_free(MEMP_RAW_PCB, pcb);
}
/**
* @ingroup raw_raw
* Create a RAW PCB.
*
* @return The RAW PCB which was created. NULL if the PCB data structure
* could not be allocated.
*
* @param proto the protocol number of the IPs payload (e.g. IP_PROTO_ICMP)
*
* @see raw_remove()
*/
struct raw_pcb *
raw_new(u8_t proto)
{
struct raw_pcb *pcb;
LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_new\n"));
pcb = (struct raw_pcb *)memp_malloc(MEMP_RAW_PCB);
/* could allocate RAW PCB? */
if (pcb != NULL) {
/* initialize PCB to all zeroes */
memset(pcb, 0, sizeof(struct raw_pcb));
pcb->protocol = proto;
pcb->ttl = RAW_TTL;
#if LWIP_MULTICAST_TX_OPTIONS
raw_set_multicast_ttl(pcb, RAW_TTL);
#endif /* LWIP_MULTICAST_TX_OPTIONS */
pcb->next = raw_pcbs;
raw_pcbs = pcb;
}
return pcb;
}
/**
* @ingroup raw_raw
* Create a RAW PCB for specific IP type.
*
* @return The RAW PCB which was created. NULL if the PCB data structure
* could not be allocated.
*
* @param type IP address type, see @ref lwip_ip_addr_type definitions.
* If you want to listen to IPv4 and IPv6 (dual-stack) packets,
* supply @ref IPADDR_TYPE_ANY as argument and bind to @ref IP_ANY_TYPE.
* @param proto the protocol number (next header) of the IPv6 packet payload
* (e.g. IP6_NEXTH_ICMP6)
*
* @see raw_remove()
*/
struct raw_pcb *
raw_new_ip_type(u8_t type, u8_t proto)
{
struct raw_pcb *pcb;
pcb = raw_new(proto);
#if LWIP_IPV4 && LWIP_IPV6
if (pcb != NULL) {
IP_SET_TYPE_VAL(pcb->local_ip, type);
IP_SET_TYPE_VAL(pcb->remote_ip, type);
}
#else /* LWIP_IPV4 && LWIP_IPV6 */
LWIP_UNUSED_ARG(type);
#endif /* LWIP_IPV4 && LWIP_IPV6 */
return pcb;
}
/** This function is called from netif.c when address is changed
*
* @param old_addr IP address of the netif before change
* @param new_addr IP address of the netif after change
*/
void raw_netif_ip_addr_changed(const ip_addr_t *old_addr, const ip_addr_t *new_addr)
{
struct raw_pcb *rpcb;
if (!ip_addr_isany(old_addr) && !ip_addr_isany(new_addr)) {
for (rpcb = raw_pcbs; rpcb != NULL; rpcb = rpcb->next) {
/* PCB bound to current local interface address? */
if (ip_addr_cmp(&rpcb->local_ip, old_addr)) {
/* The PCB is bound to the old ipaddr and
* is set to bound to the new one instead */
ip_addr_copy(rpcb->local_ip, *new_addr);
}
}
}
}
#endif /* LWIP_RAW */