BadVPN – Rev 1
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/**
* @file
*
* IPv6 fragmentation and reassembly.
*/
/*
* Copyright (c) 2010 Inico 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. 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: Ivan Delamer <delamer@inicotech.com>
*
*
* Please coordinate changes and requests with Ivan Delamer
* <delamer@inicotech.com>
*/
#ifndef LWIP_HDR_IP6_FRAG_H
#define LWIP_HDR_IP6_FRAG_H
#include "lwip/opt.h"
#include "lwip/pbuf.h"
#include "lwip/ip6_addr.h"
#include "lwip/ip6.h"
#include "lwip/netif.h"
#ifdef __cplusplus
extern "C" {
#endif
#if LWIP_IPV6 && LWIP_IPV6_REASS /* don't build if not configured for use in lwipopts.h */
/** The IPv6 reassembly timer interval in milliseconds. */
#define IP6_REASS_TMR_INTERVAL 1000
/** IP6_FRAG_COPYHEADER==1: for platforms where sizeof(void*) > 4, "struct
* ip6_reass_helper" is too large to be stored in the IPv6 fragment header, and
* will bleed into the header before it, which may be the IPv6 header or an
* extension header. This means that for each first fragment packet, we need to
* 1) make a copy of some IPv6 header fields (src+dest) that we need later on,
* just in case we do overwrite part of the IPv6 header, and 2) make a copy of
* the header data that we overwrote, so that we can restore it before either
* completing reassembly or sending an ICMPv6 reply. The last part is true even
* if this setting is disabled, but if it is enabled, we need to save a bit
* more data (up to the size of a pointer) because we overwrite more. */
#ifndef IPV6_FRAG_COPYHEADER
#define IPV6_FRAG_COPYHEADER 0
#endif
/* With IPV6_FRAG_COPYHEADER==1, a helper structure may (or, depending on the
* presence of extensions, may not) overwrite part of the IP header. Therefore,
* we copy the fields that we need from the IP header for as long as the helper
* structure may still be in place. This is easier than temporarily restoring
* those fields in the IP header each time we need to perform checks on them. */
#if IPV6_FRAG_COPYHEADER
#define IPV6_FRAG_SRC(ipr) ((ipr)->src)
#define IPV6_FRAG_DEST(ipr) ((ipr)->dest)
#else /* IPV6_FRAG_COPYHEADER */
#define IPV6_FRAG_SRC(ipr) ((ipr)->iphdr->src)
#define IPV6_FRAG_DEST(ipr) ((ipr)->iphdr->dest)
#endif /* IPV6_FRAG_COPYHEADER */
/** IPv6 reassembly helper struct.
* This is exported because memp needs to know the size.
*/
struct ip6_reassdata {
struct ip6_reassdata *next;
struct pbuf *p;
struct ip6_hdr *iphdr; /* pointer to the first (original) IPv6 header */
#if IPV6_FRAG_COPYHEADER
ip6_addr_p_t src; /* copy of the source address in the IP header */
ip6_addr_p_t dest; /* copy of the destination address in the IP header */
/* This buffer (for the part of the original header that we overwrite) will
* be slightly oversized, but we cannot compute the exact size from here. */
u8_t orig_hdr[sizeof(struct ip6_frag_hdr) + sizeof(void*)];
#else /* IPV6_FRAG_COPYHEADER */
/* In this case we still need the buffer, for sending ICMPv6 replies. */
u8_t orig_hdr[sizeof(struct ip6_frag_hdr)];
#endif /* IPV6_FRAG_COPYHEADER */
u32_t identification;
u16_t datagram_len;
u8_t nexth;
u8_t timer;
#if LWIP_IPV6_SCOPES
u8_t src_zone; /* zone of original packet's source address */
u8_t dest_zone; /* zone of original packet's destination address */
#endif /* LWIP_IPV6_SCOPES */
};
#define ip6_reass_init() /* Compatibility define */
void ip6_reass_tmr(void);
struct pbuf *ip6_reass(struct pbuf *p);
#endif /* LWIP_IPV6 && LWIP_IPV6_REASS */
#if LWIP_IPV6 && LWIP_IPV6_FRAG /* don't build if not configured for use in lwipopts.h */
#ifndef LWIP_PBUF_CUSTOM_REF_DEFINED
#define LWIP_PBUF_CUSTOM_REF_DEFINED
/** A custom pbuf that holds a reference to another pbuf, which is freed
* when this custom pbuf is freed. This is used to create a custom PBUF_REF
* that points into the original pbuf. */
struct pbuf_custom_ref {
/** 'base class' */
struct pbuf_custom pc;
/** pointer to the original pbuf that is referenced */
struct pbuf *original;
};
#endif /* LWIP_PBUF_CUSTOM_REF_DEFINED */
err_t ip6_frag(struct pbuf *p, struct netif *netif, const ip6_addr_t *dest);
#endif /* LWIP_IPV6 && LWIP_IPV6_FRAG */
#ifdef __cplusplus
}
#endif
#endif /* LWIP_HDR_IP6_FRAG_H */