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osd-contiki/core/net/sicslowpan.c

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/**
* \addtogroup sicslowpan
* @{
*/
/*
* Copyright (c) 2008, 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. Neither the name of the Institute 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 THE INSTITUTE 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 THE INSTITUTE 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 part of the Contiki operating system.
*
* $Id: sicslowpan.c,v 1.2 2008/10/14 12:26:18 adamdunkels Exp $
*/
/**
* \file
* 6lowpan implementation (RFC4944 and draft-hui-6lowpan-hc-01)
*
* \author Adam Dunkels <adam@sics.se>
* \author Nicolas Tsiftes <nvt@sics.se>
* \author Niclas Finne <nfi@sics.se>
* \author Mathilde Durvy <mdurvy@cisco.com>
* \author Julien Abeille <jabeille@cisco.com>
*/
#include <string.h>
#include "net/tcpip.h"
#include "net/uip.h"
#include "net/uip-netif.h"
#include "net/rime.h"
#include "net/sicslowpan.h"
#define DEBUG 0
#if DEBUG
u8_t p;
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINT6ADDR(addr) PRINTF(" %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x ", ((u8_t *)addr)[0], ((u8_t *)addr)[1], ((u8_t *)addr)[2], ((u8_t *)addr)[3], ((u8_t *)addr)[4], ((u8_t *)addr)[5], ((u8_t *)addr)[6], ((u8_t *)addr)[7], ((u8_t *)addr)[8], ((u8_t *)addr)[9], ((u8_t *)addr)[10], ((u8_t *)addr)[11], ((u8_t *)addr)[12], ((u8_t *)addr)[13], ((u8_t *)addr)[14], ((u8_t *)addr)[15])
#define PRINTLLADDR(lladdr) PRINTF(" %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x ",lladdr->addr[0], lladdr->addr[1], lladdr->addr[2], lladdr->addr[3],lladdr->addr[4], lladdr->addr[5],lladdr->addr[6], lladdr->addr[7])
#define PRINTRIMEBUF() PRINTF("RIME buffer: "); for(p = 0; p < rimebuf_datalen(); p++){PRINTF("%.2X", *(rime_ptr + p));} PRINTF("\n")
#define PRINTUIPBUF() PRINTF("UIP buffer: "); for(p = 0; p < uip_len; p++){PRINTF("%.2X", uip_buf[p]);}PRINTF("\n")
#define PRINTSICSLOWPANBUF() PRINTF("SICSLOWPAN buffer: "); for(p = 0; p < sicslowpan_len; p++){PRINTF("%.2X", sicslowpan_buf[p]);}PRINTF("\n")
#else
#define PRINTF(...)
#define PRINT6ADDR(addr)
#define PRINTLLADDR(lladdr)
#define PRINTRIMEBUF()
#define PRINTUIPBUF()
#define PRINTSICSLOWPANBUF()
#endif /* DEBUG == 1*/
#if UIP_LOGGING
#include <stdio.h>
void uip_log(char *msg);
#define UIP_LOG(m) uip_log(m)
#else
#define UIP_LOG(m)
#endif /* UIP_LOGGING == 1 */
/** \name Pointers in the rime buffer
* @{
*/
#define RIME_FRAG_BUF ((struct sicslowpan_frag_hdr *)rime_ptr)
#define RIME_HC1_BUF ((struct sicslowpan_hc1_hdr *)(rime_ptr + rime_hdr_len))
#define RIME_HC1_HC_UDP_BUF ((struct sicslowpan_hc1_hc_udp_hdr *)(rime_ptr + rime_hdr_len))
#define RIME_IP_BUF ((struct uip_ip_hdr *)(rime_ptr + rime_hdr_len))
#define RIME_IPHC_BUF ((struct sicslowpan_iphc_hdr *)(rime_ptr + rime_hdr_len))
/** @} */
/** \name Pointers in the sicslowpan and uip buffer
* @{
*/
#define SICSLOWPAN_IP_BUF ((struct uip_ip_hdr *)&sicslowpan_buf[UIP_LLH_LEN])
#define SICSLOWPAN_UDP_BUF ((struct uip_udp_hdr *)&sicslowpan_buf[UIP_LLIPH_LEN])
#define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])
#define UIP_UDP_BUF ((struct uip_udp_hdr *)&uip_buf[UIP_LLIPH_LEN])
/** @} */
/** \brief Size of the 802.15.4 payload (127byte - 25 for MAC header) */
#define MAC_MAX_PAYLOAD 102
/** \name General variables
* @{
*/
/** A pointer to the mac driver */
static const struct mac_driver *mac;
/**
* A pointer to the rime buffer.
* We initialize it to the beginning of the rime buffer, then
* access different fields by updating the offset rime_hdr_len.
*/
static u8_t *rime_ptr;
/**
* rime_hdr_len is the total length of (the processed) 6lowpan headers
* (fragment headers, IPV6 or HC1, HC2, and HC1 and HC2 non compressed
* fields).
*/
static u8_t rime_hdr_len;
/**
* The length of the payload in the Rime buffer.
* The payload is what comes after the compressed or uncompressed
* headers (can be the IP payload if the IP header only is compressed
* or the UDP payload if the UDP header is also compressed)
*/
static u8_t rime_payload_len;
/**
* uncomp_hdr_len is the length of the headers before compression (if HC2
* is used this includes the UDP header in addition to the IP header).
*/
static u8_t uncomp_hdr_len;
/** @} */
#if SICSLOWPAN_CONF_FRAG
/** \name Fragmentation related variables
* @{
*/
/**
* The buffer used for the 6lowpan reassembly.
* This buffer contains only the IPv6 packet (no MAC header, 6lowpan, etc).
* It has a fix size as we do not use dynamic memory allocation.
*/
static u8_t sicslowpan_buf[UIP_BUFSIZE];
/** The total length of the IPv6 packet in the sicslowpan_buf. */
static u16_t sicslowpan_len;
/**
* length of the ip packet already sent / received.
* It includes IP and transport headers.
*/
static u16_t processed_ip_len;
/** Datagram tag to be put in the fragments I send. */
static u16_t my_tag;
/** When reassembling, the tag in the fragments being merged. */
static u16_t reass_tag;
/** When reassembling, the source address of the fragments being merged */
rimeaddr_t frag_sender;
/** Reassembly %process %timer. */
static struct timer reass_timer;
/** @} */
#else /* SICSLOWPAN_CONF_FRAG */
/** The buffer used for the 6lowpan processing is uip_buf.
We do not use any additional buffer.*/
#define sicslowpan_buf uip_buf
#define sicslowpan_len uip_len
#endif /* SICSLOWPAN_CONF_FRAG */
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01
/** \name HC01 specific variables
* @{
*/
/** Addresses contexts for IPHC. */
static struct sicslowpan_addr_context
addr_contexts[SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS];
/** pointer to an address context. */
static struct sicslowpan_addr_context *context;
/** pointer to the byte where to write next inline field. */
static u8_t *hc01_ptr;
/** Index for loops. */
static u8_t i;
/** @} */
/*--------------------------------------------------------------------*/
/** \name HC01 related functions
* @{ */
/*--------------------------------------------------------------------*/
/** \brief find the context corresponding to prefix ipaddr */
static struct sicslowpan_addr_context*
addr_context_lookup_by_prefix(uip_ipaddr_t *ipaddr) {
for(i = 0; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) {
if((addr_contexts[i].used == 1) &&
uip_ipaddr_prefixcmp(&addr_contexts[i].prefix, ipaddr, 64)) {
return &addr_contexts[i];
}
}
return NULL;
}
/*--------------------------------------------------------------------*/
/** \brief find the context with the given number */
static struct sicslowpan_addr_context*
addr_context_lookup_by_number(u8_t number) {
for(i = 0; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) {
if((addr_contexts[i].used == 1) &&
addr_contexts[i].number == number) {
return &addr_contexts[i];
}
}
return NULL;
}
/*--------------------------------------------------------------------*/
/**
* \brief Compress IP/UDP header
*
* This function is called by the 6lowpan code to create a compressed
* 6lowpan packet in the rimebuf buffer from a full IPv6 packet in the
* uip_buf buffer.
*
*
* HC01 (draft-hui-6lowpan-hc, version 1)\n
*
* \note We do not support ISA100_UDP header compression
*
* For LOWPAN_UDP compression, we either compress both ports or none.
* General format with LOWPAN_UDP compression is
* \verbatim
* 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | HC01 Dsp | HC01 encoding | non |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | compressed IPv6 fields ..... |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | LOWPAN_UDP | non compressed UDP fields ... |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | L4 data ... |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* \endverbatim
* \note The context number 00 is reserved for the link local prefix.
* For unicast addresses, if we cannot compress the prefix, we neither
* compress the IID.
* \param rime_destaddr L2 destination address, needed to compress IP
* dest
*/
/*
* Address compression logic (multicast only applies to dest):
* If multicast:
* If flags (see RFC4291 section 2.7) are all 0 AND
* the 112-bit group id is mapable to a 9-bit group
* (for now all nodes and all routers groups are
* mapable),
* we compress to 16 bits
* Else unicast:
* If we have a context for the prefix,
* we elide 64 bits prefix.
* If the IID can be inferred from lower layers,
* we elide 64 bits IID
* else
* if first 49 bits of IID are 0,
* we compress IID to 16 bits (with first = 0
* to differentiate from multicast)
*
*/
static void
compress_hdr_hc01(rimeaddr_t *rime_destaddr)
{
hc01_ptr = rime_ptr + 3;
/*
* As we copy some bit-length fields, in the IPHC encoding bytes,
* we sometimes use |=
* If the field is 0, and the current bit value in memory is 1,
* this does not work. We therefore reset the IPHC encoding here
*/
memset(RIME_IPHC_BUF->encoding, 0, 2);
RIME_IPHC_BUF->dispatch = SICSLOWPAN_DISPATCH_IPHC;
/*
* Version, traffic class, flow label
* If flow label is 0, compress it. If traffic class is 0, compress it
* We have to process both in the same time as the offset of traffic class
* depends on the presence of version and flow label
*/
if(((UIP_IP_BUF->tcflow & 0x0F) == 0) &&
(UIP_IP_BUF->flow == 0)) {
/* version and flow label can be compressed */
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_VF_C;
if(((UIP_IP_BUF->vtc & 0x0F) == 0) &&
((UIP_IP_BUF->tcflow & 0xF0) == 0)) {
/* compress (elide) all */
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_TC_C;
} else {
/* compress only version and flow label */
*hc01_ptr = (UIP_IP_BUF->vtc << 4) |
(UIP_IP_BUF->tcflow >> 4);
hc01_ptr += 1;
}
} else {
/* version and flow label cannot be compressed */
if(((UIP_IP_BUF->vtc & 0x0F) == 0) &&
((UIP_IP_BUF->tcflow & 0xF0) == 0)) {
/* compress only traffic class */
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_TC_C;
*hc01_ptr = (UIP_IP_BUF->vtc & 0xF0) |
(UIP_IP_BUF->tcflow & 0x0F);
memcpy(hc01_ptr + 1, &UIP_IP_BUF->flow, 2);
hc01_ptr += 3;
} else {
/* compress nothing */
memcpy(hc01_ptr, &UIP_IP_BUF->vtc, 4);
hc01_ptr += 4;
}
}
/* Note that the payload length is always compressed */
/* Next header. We compress it if UDP */
#if UIP_CONF_UDP
if(UIP_IP_BUF->proto == UIP_PROTO_UDP) {
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_NH_C;
} else {
#endif /*UIP_CONF_UDP*/
*hc01_ptr = UIP_IP_BUF->proto;
hc01_ptr += 1;
#if UIP_CONF_UDP
}
#endif /*UIP_CONF_UDP*/
/*
* Hop limit
* if 1: compress, encoding is 01
* if 64: compress, encoding is 10
* if 255: compress, encoding is 11
* else do not compress
*/
switch(UIP_IP_BUF->ttl) {
case 1:
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_TTL_1;
break;
case 64:
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_TTL_64;
break;
case 255:
RIME_IPHC_BUF->encoding[0] |= SICSLOWPAN_IPHC_TTL_255;
break;
default:
*hc01_ptr = UIP_IP_BUF->ttl;
hc01_ptr += 1;
break;
}
/* source address - cannot be multicast */
if((context = addr_context_lookup_by_prefix(&UIP_IP_BUF->srcipaddr))
!= NULL) {
/* elide the prefix */
RIME_IPHC_BUF->encoding[1] |= context->number << 4;
if(uip_is_addr_mac_addr_based(&UIP_IP_BUF->srcipaddr, &uip_lladdr)){
/* elide the IID */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_SAM_0;
} else {
if(sicslowpan_is_iid_16_bit_compressable(&UIP_IP_BUF->srcipaddr)){
/* compress IID to 16 bits */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_SAM_16;
memcpy(hc01_ptr, &UIP_IP_BUF->srcipaddr.u16[7], 2);
hc01_ptr += 2;
} else {
/* do not compress IID */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_SAM_64;
memcpy(hc01_ptr, &UIP_IP_BUF->srcipaddr.u16[4], 8);
hc01_ptr += 8;
}
}
} else {
/* send the full address */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_SAM_I;
memcpy(hc01_ptr, &UIP_IP_BUF->srcipaddr.u16[0], 16);
hc01_ptr += 16;
}
/* dest address*/
if(uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
/* Address is multicast, try to compress */
if(sicslowpan_is_mcast_addr_compressable(&UIP_IP_BUF->destipaddr)) {
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_16;
/* 3 first bits = 101 */
*hc01_ptr = SICSLOWPAN_IPHC_MCAST_RANGE;
/* bits 3-6 = scope = bits 8-11 in 128 bits address */
*hc01_ptr |= (UIP_IP_BUF->destipaddr.u8[1] & 0x0F) << 1;
/*
* bits 7 - 15 = 9-bit group
* We just copy the last byte because it works
* with currently supported groups
*/
*(hc01_ptr + 1) = UIP_IP_BUF->destipaddr.u8[15];
hc01_ptr += 2;
} else {
/* send the full address */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_I;
memcpy(hc01_ptr, &UIP_IP_BUF->destipaddr.u16[0], 16);
hc01_ptr += 16;
}
} else {
/* Address is unicast, try to compress */
if((context = addr_context_lookup_by_prefix(&UIP_IP_BUF->destipaddr)) != NULL) {
/* elide the prefix */
RIME_IPHC_BUF->encoding[1] |= context->number;
if(uip_is_addr_mac_addr_based(&UIP_IP_BUF->destipaddr, (uip_lladdr_t *)rime_destaddr)) {
/* elide the IID */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_0;
} else {
if(sicslowpan_is_iid_16_bit_compressable(&UIP_IP_BUF->destipaddr)) {
/* compress IID to 16 bits */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_16;
memcpy(hc01_ptr, &UIP_IP_BUF->destipaddr.u16[7], 2);
hc01_ptr += 2;
} else {
/* do not compress IID */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_64;
memcpy(hc01_ptr, &UIP_IP_BUF->destipaddr.u16[4], 8);
hc01_ptr += 8;
}
}
} else {
/* send the full address */
RIME_IPHC_BUF->encoding[1] |= SICSLOWPAN_IPHC_DAM_I;
memcpy(hc01_ptr, &UIP_IP_BUF->destipaddr.u16[0], 16);
hc01_ptr += 16;
}
}
uncomp_hdr_len = UIP_IPH_LEN;
#if UIP_CONF_UDP
/* UDP header compression */
if(UIP_IP_BUF->proto == UIP_PROTO_UDP) {
if(HTONS(UIP_UDP_BUF->srcport) >= SICSLOWPAN_UDP_PORT_MIN &&
HTONS(UIP_UDP_BUF->srcport) < SICSLOWPAN_UDP_PORT_MAX &&
HTONS(UIP_UDP_BUF->destport) >= SICSLOWPAN_UDP_PORT_MIN &&
HTONS(UIP_UDP_BUF->destport) < SICSLOWPAN_UDP_PORT_MAX) {
/* we can compress. Copy compressed ports, full chcksum */
*hc01_ptr = SICSLOWPAN_NHC_UDP_C;
*(hc01_ptr + 1) =
(u8_t)((HTONS(UIP_UDP_BUF->srcport) -
SICSLOWPAN_UDP_PORT_MIN) << 4) +
(u8_t)((HTONS(UIP_UDP_BUF->destport) -
SICSLOWPAN_UDP_PORT_MIN));
memcpy(hc01_ptr + 2, &UIP_UDP_BUF->udpchksum, 2);
hc01_ptr += 4;
} else {
/* we cannot compress. Copy uncompressed ports, full chcksum */
*hc01_ptr = SICSLOWPAN_NHC_UDP_I;
memcpy(hc01_ptr + 1, &UIP_UDP_BUF->srcport, 4);
memcpy(hc01_ptr + 5, &UIP_UDP_BUF->udpchksum, 2);
hc01_ptr += 7;
}
uncomp_hdr_len += UIP_UDPH_LEN;
}
#endif /*UIP_CONF_UDP*/
rime_hdr_len = hc01_ptr - rime_ptr;
return;
}
/*--------------------------------------------------------------------*/
/**
* \brief Uncompress HC01 (i.e., IPHC and LOWPAN_UDP) headers and put
* them in sicslowpan_buf
*
* This function is called by the input function when the dispatch is
* HC01.
* We %process the packet in the rime buffer, uncompress the header
* fields, and copy the result in the sicslowpan buffer.
* At the end of the decompression, rime_hdr_len and uncompressed_hdr_len
* are set to the appropriate values
*
* \param ip_len Equal to 0 if the packet is not a fragment (IP length
* is then inferred from the L2 length), non 0 if the packet is a 1st
* fragment.
*/
/* Processing Details
* - IP header
* We process the fields in their order of appearance in the normal
* IP header, with two exceptions:
* - next header: field when it is compressed: we need to reach the
* NHC encoding to know which is the next header
* - length: we need to know the length of headers in rime buffer
* (i.e. the final value of rime_hdr_len)
* - Addresses processing
* We do the same for src and dest, even though a multicast source
* address is wrong. IP layer will handle this. The logic is:
*
* Switch(compression)
* case no compression: copy full address
* case 64bit compressed address:
* find the context, copy prefix from context,
* copy IID from packet
* case all 128 bit of the address are ellided:
* find the context, copy prefix from context,
* infer IID from L2 address
* case 16 bit compressed address:
* if 1st bit = 0 (unicast case)
* copy prefix from context, then 48 zeros
* then 16 last bits from packet
* else (multicast case)
* first byte = FF, flags = 0, copy scope
* from packet, infer 112 bits group ID from
* 9 bit group id
*
* - UDP header, for LOWPAN_UDP compression
* The only trick is that we fill the length field at the end of
* the function.
*/
static void
uncompress_hdr_hc01(u16_t ip_len) {
hc01_ptr = rime_ptr + rime_hdr_len + 3;
/* Version and flow label */
if((RIME_IPHC_BUF->encoding[0] & 0x40) == 0) {
/* Version and flow label are carried inline */
if((RIME_IPHC_BUF->encoding[0] & 0x80) == 0) {
/* Traffic class is carried inline */
memcpy(&SICSLOWPAN_IP_BUF->vtc, hc01_ptr, 4);
hc01_ptr += 4;
} else {
/* Traffic class is compressed */
SICSLOWPAN_IP_BUF->vtc = 0x60;
SICSLOWPAN_IP_BUF->tcflow = *hc01_ptr & 0x0F;
memcpy(&SICSLOWPAN_IP_BUF->flow, hc01_ptr + 1, 2);
hc01_ptr += 3;
}
} else {
/* Version and flow label are compressed */
if((RIME_IPHC_BUF->encoding[0] & 0x80) == 0) {
/* Traffic class is inline */
SICSLOWPAN_IP_BUF->vtc = 0x60 | (*hc01_ptr >> 4);
SICSLOWPAN_IP_BUF->tcflow = *hc01_ptr << 4;
hc01_ptr += 1;
} else {
/* Traffic class is compressed */
SICSLOWPAN_IP_BUF->vtc = 0x60;
SICSLOWPAN_IP_BUF->tcflow = 0;
}
SICSLOWPAN_IP_BUF->flow = 0;
}
/* Next Header */
if((RIME_IPHC_BUF->encoding[0] & 0x20) == 0) {
/* Next header is carried inline */
SICSLOWPAN_IP_BUF->proto = *hc01_ptr;
hc01_ptr += 1;
}
/* Hop limit */
switch(RIME_IPHC_BUF->encoding[0] & 0x18) {
case SICSLOWPAN_IPHC_TTL_1:
SICSLOWPAN_IP_BUF->ttl = 1;
break;
case SICSLOWPAN_IPHC_TTL_64:
SICSLOWPAN_IP_BUF->ttl = 64;
break;
case SICSLOWPAN_IPHC_TTL_255:
SICSLOWPAN_IP_BUF->ttl = 255;
break;
case SICSLOWPAN_IPHC_TTL_I:
SICSLOWPAN_IP_BUF->ttl = *hc01_ptr;
hc01_ptr += 1;
break;
}
/* Source address */
context =
addr_context_lookup_by_number((RIME_IPHC_BUF->encoding[1] & 0x30) >> 4);
switch(RIME_IPHC_BUF->encoding[1] & 0xC0) {
case SICSLOWPAN_IPHC_SAM_0:
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
/* copy prefix from context */
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr, context->prefix, 8);
/* infer IID from L2 address */
uip_netif_addr_autoconf_set(&SICSLOWPAN_IP_BUF->srcipaddr,
(uip_lladdr_t *)rimebuf_addr(RIMEBUF_ADDR_SENDER));
break;
case SICSLOWPAN_IPHC_SAM_16:
if((*hc01_ptr & 0x80) == 0) {
/* unicast address */
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr, context->prefix, 8);
/* copy 6 NULL bytes then 2 last bytes of IID */
memset(&SICSLOWPAN_IP_BUF->srcipaddr.u8[8], 0, 6);
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr.u8[14], hc01_ptr, 2);
hc01_ptr += 2;
} else {
/* multicast address check the 9-bit group-id is known */
if(sicslowpan_is_mcast_addr_decompressable(hc01_ptr)) {
SICSLOWPAN_IP_BUF->srcipaddr.u8[0] = 0xFF;
SICSLOWPAN_IP_BUF->srcipaddr.u8[1] = (*hc01_ptr >> 1) & 0x0F;
memset(&SICSLOWPAN_IP_BUF->srcipaddr.u8[2], 0, 13);
SICSLOWPAN_IP_BUF->srcipaddr.u8[15] = *(hc01_ptr + 1);
hc01_ptr += 2;
} else {
PRINTF("sicslowpan uncompress_hdr: error unknown compressed mcast address\n");
return;
}
}
break;
case SICSLOWPAN_IPHC_SAM_64:
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
/* copy prefix from context */
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr, context->prefix, 8);
/* copy IID from packet */
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr.u8[8], hc01_ptr, 8);
hc01_ptr += 8;
break;
case SICSLOWPAN_IPHC_SAM_I:
/* copy whole address from packet */
memcpy(&SICSLOWPAN_IP_BUF->srcipaddr.u8[0], hc01_ptr, 16);
hc01_ptr += 16;
break;
}
/* Destination address */
context = addr_context_lookup_by_number(RIME_IPHC_BUF->encoding[1] & 0x03);
switch(RIME_IPHC_BUF->encoding[1] & 0x0C) {
case SICSLOWPAN_IPHC_DAM_0:
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
/* copy prefix from context */
memcpy(&SICSLOWPAN_IP_BUF->destipaddr, context->prefix, 8);
/* infer IID from L2 address */
uip_netif_addr_autoconf_set(&SICSLOWPAN_IP_BUF->destipaddr,
(uip_lladdr_t *)rimebuf_addr(RIMEBUF_ADDR_RECEIVER));
break;
case SICSLOWPAN_IPHC_DAM_16:
if((*hc01_ptr & 0x80) == 0) {
/* unicast address */
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
memcpy(&SICSLOWPAN_IP_BUF->destipaddr, context->prefix, 8);
/* copy 6 NULL bytes then 2 last bytes of IID */
memset(&SICSLOWPAN_IP_BUF->destipaddr.u8[8], 0, 6);
memcpy(&SICSLOWPAN_IP_BUF->destipaddr.u8[14], hc01_ptr, 2);
hc01_ptr += 2;
} else {
/* multicast address check the 9-bit group-id is known */
if(sicslowpan_is_mcast_addr_decompressable(hc01_ptr)) {
SICSLOWPAN_IP_BUF->destipaddr.u8[0] = 0xFF;
SICSLOWPAN_IP_BUF->destipaddr.u8[1] = (*hc01_ptr >> 1) & 0x0F;
memset(&SICSLOWPAN_IP_BUF->destipaddr.u8[2], 0, 13);
SICSLOWPAN_IP_BUF->destipaddr.u8[15] = *(hc01_ptr + 1);
hc01_ptr += 2;
} else {
PRINTF("sicslowpan uncompress_hdr: error unknown compressed mcast address\n");
return;
}
}
break;
case SICSLOWPAN_IPHC_DAM_64:
if(context == NULL) {
PRINTF("sicslowpan uncompress_hdr: error context not found\n");
return;
}
memcpy(&SICSLOWPAN_IP_BUF->destipaddr, context->prefix, 8);
memcpy(&SICSLOWPAN_IP_BUF->destipaddr.u8[8], hc01_ptr, 8);
hc01_ptr += 8;
break;
case SICSLOWPAN_IPHC_DAM_I:
/* copy whole address from packet */
memcpy(&SICSLOWPAN_IP_BUF->destipaddr.u8[0], hc01_ptr, 16);
hc01_ptr += 16;
break;
}
uncomp_hdr_len += UIP_IPH_LEN;
/* Next header processing - continued */
if((RIME_IPHC_BUF->encoding[0] & 0x20) != 0) {
/* The next header is compressed, NHC is following */
if((*hc01_ptr & 0xFC) == SICSLOWPAN_NHC_UDP_ID) {
SICSLOWPAN_IP_BUF->proto = UIP_PROTO_UDP;
switch(*hc01_ptr) {
case SICSLOWPAN_NHC_UDP_C:
/* 1 byte for NHC, 1 byte for ports, 2 bytes chksum */
SICSLOWPAN_UDP_BUF->srcport = HTONS(SICSLOWPAN_UDP_PORT_MIN +
(*(hc01_ptr + 1) >> 4));
SICSLOWPAN_UDP_BUF->destport = HTONS(SICSLOWPAN_UDP_PORT_MIN +
((*(hc01_ptr + 1)) & 0x0F));
memcpy(&SICSLOWPAN_UDP_BUF->udpchksum, hc01_ptr + 2, 2);
hc01_ptr += 4;
break;
case SICSLOWPAN_NHC_UDP_I:
/* 1 byte for NHC, 4 byte for ports, 2 bytes chksum */
memcpy(&SICSLOWPAN_UDP_BUF->srcport, hc01_ptr + 1, 2);
memcpy(&SICSLOWPAN_UDP_BUF->destport, hc01_ptr + 3, 2);
memcpy(&SICSLOWPAN_UDP_BUF->udpchksum, hc01_ptr + 5, 2);
hc01_ptr += 7;
break;
default:
PRINTF("sicslowpan uncompress_hdr: error unsupported UDP compression\n");
return;
}
uncomp_hdr_len += UIP_UDPH_LEN;
}
}
rime_hdr_len = hc01_ptr - rime_ptr;
/* IP length field. */
if(ip_len == 0) {
/* This is not a fragmented packet */
SICSLOWPAN_IP_BUF->len[0] = 0;
SICSLOWPAN_IP_BUF->len[1] = rimebuf_datalen() - rime_hdr_len + uncomp_hdr_len - UIP_IPH_LEN;
} else {
/* This is a 1st fragment */
SICSLOWPAN_IP_BUF->len[0] = (ip_len - UIP_IPH_LEN) >> 8;
SICSLOWPAN_IP_BUF->len[1] = (ip_len - UIP_IPH_LEN) & 0x00FF;
}
/* length field in UDP header */
if(SICSLOWPAN_IP_BUF->proto == UIP_PROTO_UDP) {
memcpy(&SICSLOWPAN_UDP_BUF->udplen, &SICSLOWPAN_IP_BUF->len[0], 2);
}
return;
}
/** @} */
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01*/
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1
/*--------------------------------------------------------------------*/
/** \name HC1 compression and uncompression functions
* @{ */
/*--------------------------------------------------------------------*/
/**
* \brief Compress IP/UDP header using HC1 and HC_UDP
*
* This function is called by the 6lowpan code to create a compressed
* 6lowpan packet in the rimebuf buffer from a full IPv6 packet in the
* uip_buf buffer.
*
*
* If we can compress everything, we use HC1 dispatch, if not we use
* IPv6 dispatch.\n
* We can compress everything if:
* - IP version is
* - Flow label and traffic class are 0
* - Both src and dest ip addresses are link local
* - Both src and dest interface ID are recoverable from lower layer
* header
* - Next header is either ICMP, UDP or TCP
* Moreover, if next header is UDP, we try to compress it using HC_UDP.
* This is feasible is both ports are between F0B0 and F0B0 + 15\n\n
*
* Resulting header structure:
* - For ICMP, TCP, non compressed UDP\n
* HC1 encoding = 11111010 (UDP) 11111110 (TCP) 11111100 (ICMP)\n
* \verbatim
* 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | LoWPAN HC1 Dsp | HC1 encoding | IPv6 Hop limit| L4 hdr + data|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* \endverbatim
*
* - For compressed UDP
* HC1 encoding = 11111011, HC_UDP encoding = 11100000\n
* \verbatim
* 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | LoWPAN HC1 Dsp| HC1 encoding | HC_UDP encod.| IPv6 Hop limit|
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | src p.| dst p.| UDP checksum | L4 data...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* \endverbatim
*
* \param rime_destaddr L2 destination address, needed to compress the
* IP destination field
*/
static void
compress_hdr_hc1(rimeaddr_t *rime_destaddr)
{
/*
* Check if all the assumptions for full compression
* are valid :
*/
if(UIP_IP_BUF->vtc != 0x60 ||
UIP_IP_BUF->tcflow != 0 ||
UIP_IP_BUF->flow != 0 ||
!uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr) ||
!uip_is_addr_mac_addr_based(&UIP_IP_BUF->srcipaddr, &uip_lladdr) ||
!uip_is_addr_link_local(&UIP_IP_BUF->destipaddr) ||
!uip_is_addr_mac_addr_based(&UIP_IP_BUF->destipaddr,
(uip_lladdr_t *)rime_destaddr) ||
(UIP_IP_BUF->proto != UIP_PROTO_ICMP6 &&
UIP_IP_BUF->proto != UIP_PROTO_UDP &&
UIP_IP_BUF->proto != UIP_PROTO_TCP))
{
/*
* IPV6 DISPATCH
* Something cannot be compressed, use IPV6 DISPATCH,
* compress nothing, copy IPv6 header in rime buffer
*/
*rime_ptr = SICSLOWPAN_DISPATCH_IPV6;
rime_hdr_len += SICSLOWPAN_IPV6_HDR_LEN;
memcpy(rime_ptr + rime_hdr_len, UIP_IP_BUF, UIP_IPH_LEN);
rime_hdr_len += UIP_IPH_LEN;
uncomp_hdr_len += UIP_IPH_LEN;
} else {
/*
* HC1 DISPATCH
* maximum compresssion:
* All fields in the IP header but Hop Limit are elided
* If next header is UDP, we compress UDP header using HC2
*/
RIME_HC1_BUF->dispatch = SICSLOWPAN_DISPATCH_HC1;
uncomp_hdr_len += UIP_IPH_LEN;
switch(UIP_IP_BUF->proto) {
case UIP_PROTO_ICMP6:
/* HC1 encoding and ttl */
RIME_HC1_BUF->encoding = 0xFC;
RIME_HC1_BUF->ttl = UIP_IP_BUF->ttl;
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
break;
#if UIP_CONF_TCP
case UIP_PROTO_TCP:
/* HC1 encoding and ttl */
RIME_HC1_BUF->encoding = 0xFE;
RIME_HC1_BUF->ttl = UIP_IP_BUF->ttl;
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
break;
#endif /* UIP_CONF_TCP */
#if UIP_CONF_UDP
case UIP_PROTO_UDP:
/*
* try to compress UDP header (we do only full compression).
* This is feasible if both src and dest ports are between
* SICSLOWPAN_UDP_PORT_MIN and SICSLOWPAN_UDP_PORT_MIN + 15
*/
PRINTF("local/remote port %u/%u\n",UIP_UDP_BUF->srcport,UIP_UDP_BUF->destport);
if(HTONS(UIP_UDP_BUF->srcport) >= SICSLOWPAN_UDP_PORT_MIN &&
HTONS(UIP_UDP_BUF->srcport) < SICSLOWPAN_UDP_PORT_MAX &&
HTONS(UIP_UDP_BUF->destport) >= SICSLOWPAN_UDP_PORT_MIN &&
HTONS(UIP_UDP_BUF->destport) < SICSLOWPAN_UDP_PORT_MAX) {
/* HC1 encoding */
RIME_HC1_HC_UDP_BUF->hc1_encoding = 0xFB;
/* HC_UDP encoding, ttl, src and dest ports, checksum */
RIME_HC1_HC_UDP_BUF->hc_udp_encoding = 0xE0;
RIME_HC1_HC_UDP_BUF->ttl = UIP_IP_BUF->ttl;
RIME_HC1_HC_UDP_BUF->ports = (u8_t)((HTONS(UIP_UDP_BUF->srcport) -
SICSLOWPAN_UDP_PORT_MIN) << 4) +
(u8_t)((HTONS(UIP_UDP_BUF->destport) - SICSLOWPAN_UDP_PORT_MIN));
RIME_HC1_HC_UDP_BUF->udpchksum = UIP_UDP_BUF->udpchksum;
rime_hdr_len += SICSLOWPAN_HC1_HC_UDP_HDR_LEN;
uncomp_hdr_len += UIP_UDPH_LEN;
} else {
/* HC1 encoding and ttl */
RIME_HC1_BUF->encoding = 0xFA;
RIME_HC1_BUF->ttl = UIP_IP_BUF->ttl;
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
}
break;
#endif /*UIP_CONF_UDP*/
}
}
return;
}
/*--------------------------------------------------------------------*/
/**
* \brief Uncompress HC1 (and HC_UDP) headers and put them in
* sicslowpan_buf
*
* This function is called by the input function when the dispatch is
* HC1.
* We %process the packet in the rime buffer, uncompress the header
* fields, and copy the result in the sicslowpan buffer.
* At the end of the decompression, rime_hdr_len and uncompressed_hdr_len
* are set to the appropriate values
*
* \param ip_len Equal to 0 if the packet is not a fragment (IP length
* is then inferred from the L2 length), non 0 if the packet is a 1st
* fragment.
*/
static void
uncompress_hdr_hc1(u16_t ip_len) {
/* version, traffic class, flow label */
SICSLOWPAN_IP_BUF->vtc = 0x60;
SICSLOWPAN_IP_BUF->tcflow = 0;
SICSLOWPAN_IP_BUF->flow = 0;
/* src and dest ip addresses */
uip_ip6addr(&SICSLOWPAN_IP_BUF->srcipaddr, 0xfe80, 0, 0, 0, 0, 0, 0, 0);
uip_netif_addr_autoconf_set(&SICSLOWPAN_IP_BUF->srcipaddr,
(uip_lladdr_t *)rimebuf_addr(RIMEBUF_ADDR_SENDER));
uip_ip6addr(&SICSLOWPAN_IP_BUF->destipaddr, 0xfe80, 0, 0, 0, 0, 0, 0, 0);
uip_netif_addr_autoconf_set(&SICSLOWPAN_IP_BUF->destipaddr,
(uip_lladdr_t *)rimebuf_addr(RIMEBUF_ADDR_RECEIVER));
uncomp_hdr_len += UIP_IPH_LEN;
/* Next header field */
switch(RIME_HC1_BUF->encoding & 0x06) {
case SICSLOWPAN_HC1_NH_ICMP6:
SICSLOWPAN_IP_BUF->proto = UIP_PROTO_ICMP6;
SICSLOWPAN_IP_BUF->ttl = RIME_HC1_BUF->ttl;
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
break;
#if UIP_CONF_TCP
case SICSLOWPAN_HC1_NH_TCP:
SICSLOWPAN_IP_BUF->proto = UIP_PROTO_TCP;
SICSLOWPAN_IP_BUF->ttl = RIME_HC1_BUF->ttl;
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
break;
#endif/* UIP_CONF_TCP */
#if UIP_CONF_UDP
case SICSLOWPAN_HC1_NH_UDP:
SICSLOWPAN_IP_BUF->proto = UIP_PROTO_UDP;
if(RIME_HC1_HC_UDP_BUF->hc1_encoding & 0x01) {
/* UDP header is compressed with HC_UDP */
if(RIME_HC1_HC_UDP_BUF->hc_udp_encoding !=
SICSLOWPAN_HC_UDP_ALL_C) {
PRINTF("sicslowpan (uncompress_hdr), packet not supported");
return;
}
/* IP TTL */
SICSLOWPAN_IP_BUF->ttl = RIME_HC1_HC_UDP_BUF->ttl;
/* UDP ports, len, checksum */
SICSLOWPAN_UDP_BUF->srcport = HTONS(SICSLOWPAN_UDP_PORT_MIN +
(RIME_HC1_HC_UDP_BUF->ports >> 4));
SICSLOWPAN_UDP_BUF->destport = HTONS(SICSLOWPAN_UDP_PORT_MIN +
(RIME_HC1_HC_UDP_BUF->ports & 0x0F));
SICSLOWPAN_UDP_BUF->udpchksum = RIME_HC1_HC_UDP_BUF->udpchksum;
uncomp_hdr_len += UIP_UDPH_LEN;
rime_hdr_len += SICSLOWPAN_HC1_HC_UDP_HDR_LEN;
} else {
rime_hdr_len += SICSLOWPAN_HC1_HDR_LEN;
}
break;
#endif/* UIP_CONF_UDP */
default:
/* this shouldn't happen, drop */
return;
}
/* IP length field. */
if(ip_len == 0) {
/* This is not a fragmented packet */
SICSLOWPAN_IP_BUF->len[0] = 0;
SICSLOWPAN_IP_BUF->len[1] = rimebuf_datalen() - rime_hdr_len + uncomp_hdr_len - UIP_IPH_LEN;
} else {
/* This is a 1st fragment */
SICSLOWPAN_IP_BUF->len[0] = (ip_len - UIP_IPH_LEN) >> 8;
SICSLOWPAN_IP_BUF->len[1] = (ip_len - UIP_IPH_LEN) & 0x00FF;
}
/* length field in UDP header */
if(SICSLOWPAN_IP_BUF->proto == UIP_PROTO_UDP) {
memcpy(&SICSLOWPAN_UDP_BUF->udplen, &SICSLOWPAN_IP_BUF->len[0], 2);
}
return;
}
/** @} */
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1*/
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_IPV6
/*--------------------------------------------------------------------*/
/** \name IPv6 dispatch "compression" function
* @{ */
/*--------------------------------------------------------------------*/
/* \brief Packets "Compression" when only IPv6 dispatch is used
*
* There is no compression in this case, all fields are sent
* inline. We just add the IPv6 dispatch byte before the packet.
* \verbatim
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | IPv6 Dsp | IPv6 header and payload ...
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* \endverbatim
*/
static void
compress_hdr_ipv6(rimeaddr_t *rime_destaddr) {
*rime_ptr = SICSLOWPAN_DISPATCH_IPV6;
rime_hdr_len += SICSLOWPAN_IPV6_HDR_LEN;
memcpy(rime_ptr + rime_hdr_len, UIP_IP_BUF, UIP_IPH_LEN);
rime_hdr_len += UIP_IPH_LEN;
uncomp_hdr_len += UIP_IPH_LEN;
return;
}
/** @} */
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_IPV6*/
/*--------------------------------------------------------------------*/
/** \name Input/output functions common to all compression schemes
* @{ */
/*--------------------------------------------------------------------*/
/**
* \brief This function is called by the 6lowpan code to send out a
* packet.
* \param dest the link layer destination address of the packet
*/
static void
send_packet(rimeaddr_t *dest)
{
/* Set the link layer destination address for the packet as a
* rimebuf attribute. The MAC layer can access the destination
* address with the function "rimebuf_addr(RIMEBUF_ADDR_RECEIVER);
*/
rimebuf_set_addr(RIMEBUF_ADDR_RECEIVER, dest);
if(mac != NULL) {
/** \todo: Fix sending delays so they aren't blocking, or even better would
* be to figure out how to get rid of delays entirely */
#if DEBUG
#warning "*************************************************************"
#warning "Debug code enabled in sicslowpan.c, you MUST enable debug "
#warning "code in sicslowmac.c as well, and ALL nodes on network must "
#warning "have debug code in sicslowmac.c enabled. See documentation "
#warning "*************************************************************"
#endif
mac->send();
}
}
/** \brief Take an IP packet and format it to be sent on an 802.15.4
* network using 6lowpan.
* \param localdest The MAC address of the destination
*
* The IP packet is initially in uip_buf. Its header is compressed
* and if necessary it is fragmented. The resulting
* packet/fragments are put in rimebuf and delivered to the 802.15.4
* MAC.
*/
static u8_t
output(uip_lladdr_t *localdest)
{
/* The MAC address of the destination of the packet */
rimeaddr_t dest;
/* init */
uncomp_hdr_len = 0;
rime_hdr_len = 0;
/* reset rime buffer */
rimebuf_clear();
rime_ptr = rimebuf_dataptr();
/*
* The destination address will be tagged to each outbound
* packet. If the argument localdest is NULL, we are sending a
* broadcast packet.
*/
if(localdest == NULL) {
rimeaddr_copy(&dest, &rimeaddr_null);
} else {
rimeaddr_copy(&dest, (const rimeaddr_t *)localdest);
}
PRINTF("sicslowpan output: sending packet len %d\n", uip_len);
/* Try to compress the headers */
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1
compress_hdr_hc1(&dest);
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1*/
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_IPV6
compress_hdr_ipv6(&dest);
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_IPV6*/
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01
compress_hdr_hc01(&dest);
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01*/
PRINTF("sicslowpan output: header of len %d\n", rime_hdr_len);
if(uip_len - uncomp_hdr_len > MAC_MAX_PAYLOAD - rime_hdr_len) {
#if SICSLOWPAN_CONF_FRAG
/*
* The outbound IPv6 packet is too large to fit into a single 15.4
* packet, so we fragment it into multiple packets and send them.
* The first fragment contains frag1 dispatch, then
* IPv6/HC1/HC01/HC_UDP dispatchs/headers.
* The following fragments contain only the fragn dispatch.
*/
/* Create 1st Fragment */
PRINTF("sicslowpan output: 1rst fragment ");
/* move HC1/HC01/IPv6 header */
memmove(rime_ptr + SICSLOWPAN_FRAG1_HDR_LEN, rime_ptr, rime_hdr_len);
/*
* FRAG1 dispatch + header
* Note that the length is in units of 8 bytes
*/
RIME_FRAG_BUF->dispatch_size =
htons((SICSLOWPAN_DISPATCH_FRAG1 << 8) | uip_len);
RIME_FRAG_BUF->tag = htons(my_tag);
/* Copy payload and send */
rime_hdr_len += SICSLOWPAN_FRAG1_HDR_LEN;
rime_payload_len = (MAC_MAX_PAYLOAD - rime_hdr_len) & 0xf8;
PRINTF("(len %d, tag %d)\n", rime_payload_len, my_tag);
memcpy(rime_ptr + rime_hdr_len,
(void *)UIP_IP_BUF + uncomp_hdr_len, rime_payload_len);
rimebuf_set_datalen(rime_payload_len + rime_hdr_len);
send_packet(&dest);
/* set processed_ip_len to what we already sent from the IP payload*/
processed_ip_len = rime_payload_len + uncomp_hdr_len;
/*
* Create following fragments
* Datagram tag is already in the buffer, we need to set the
* FRAGN dispatch and for each fragment, the offset
*/
rime_hdr_len = SICSLOWPAN_FRAGN_HDR_LEN;
RIME_FRAG_BUF->dispatch_size =
htons((SICSLOWPAN_DISPATCH_FRAGN << 8) | uip_len);
rime_payload_len = (MAC_MAX_PAYLOAD - rime_hdr_len) & 0xf8;
while(processed_ip_len < uip_len){
PRINTF("sicslowpan output: fragment ");
RIME_FRAG_BUF->offset = processed_ip_len >> 3;
/* Copy payload and send */
if(uip_len - processed_ip_len < rime_payload_len){
/* last fragment */
rime_payload_len = uip_len - processed_ip_len;
}
PRINTF("(offset %d, len %d, tag %d)\n",
processed_ip_len >> 3, rime_payload_len, my_tag);
memcpy(rime_ptr + rime_hdr_len,
(void *)UIP_IP_BUF + processed_ip_len, rime_payload_len);
rimebuf_set_datalen(rime_payload_len + rime_hdr_len);
send_packet(&dest);
processed_ip_len += rime_payload_len;
}
/* end: reset global variables */
my_tag++;
processed_ip_len = 0;
#else /* SICSLOWPAN_CONF_FRAG */
PRINTF("sicslowpan output: Packet too large to be sent without fragmentation support; dropping packet\n");
return 0;
#endif /* SICSLOWPAN_CONF_FRAG */
} else {
/*
* The packet does not need to be fragmented
* copy "payload" and send
*/
memcpy(rime_ptr + rime_hdr_len, (void *)UIP_IP_BUF + uncomp_hdr_len,
uip_len - uncomp_hdr_len);
rimebuf_set_datalen(uip_len - uncomp_hdr_len + rime_hdr_len);
send_packet(&dest);
}
return 1;
}
/*--------------------------------------------------------------------*/
/** \brief Process a received 6lowpan packet.
* \param r The MAC layer
*
* The 6lowpan packet is put in rimebuf by the MAC. If its a frag1 or
* a non-fragmented packet we first uncompress the IP header. The
* 6lowpan payload and possibly the uncompressed IP header are then
* copied in siclowpan_buf. If the IP packet is complete it is copied
* to uip_buf and the IP layer is called.
*
* \note We do not check for overlapping sicslowpan fragments
* (it is a SHALL in the RFC 4944 and should never happen)
*/
static void
input(const struct mac_driver *r)
{
/* size of the IP packet (read from fragment) */
u16_t frag_size = 0;
/* offset of the fragment in the IP packet */
u8_t frag_offset = 0;
#if SICSLOWPAN_CONF_FRAG
/* tag of the fragment */
u16_t frag_tag = 0;
#endif /*SICSLOWPAN_CONF_FRAG*/
/* init */
uncomp_hdr_len = 0;
rime_hdr_len = 0;
/* The MAC puts the 15.4 payload inside the RIME data buffer */
rime_ptr = rimebuf_dataptr();
#if SICSLOWPAN_CONF_FRAG
/* if reassembly timed out, cancel it */
if(timer_expired(&reass_timer)){
sicslowpan_len = 0;
processed_ip_len = 0;
}
/*
* Since we don't support the mesh and broadcast header, the first header
* we look for is the fragmentation header
*/
switch((ntohs(RIME_FRAG_BUF->dispatch_size) & 0xf800) >> 8) {
case SICSLOWPAN_DISPATCH_FRAG1:
PRINTF("sicslowpan input: FRAG1 ");
frag_offset = 0;
frag_size = (ntohs(RIME_FRAG_BUF->dispatch_size) & 0x07ff);
frag_tag = ntohs(RIME_FRAG_BUF->tag);
PRINTF("size %d, tag %d, offset %d)\n",
frag_size, frag_tag, frag_offset);
rime_hdr_len += SICSLOWPAN_FRAG1_HDR_LEN;
break;
case SICSLOWPAN_DISPATCH_FRAGN:
/*
* set offset, tag, size
* Offset is in units of 8 bytes
*/
PRINTF("sicslowpan input: FRAGN ");
frag_offset = RIME_FRAG_BUF->offset;
frag_tag = ntohs(RIME_FRAG_BUF->tag);
frag_size = (ntohs(RIME_FRAG_BUF->dispatch_size) & 0x07ff);
PRINTF("size %d, tag %d, offset %d)\n",
frag_size, frag_tag, frag_offset);
rime_hdr_len += SICSLOWPAN_FRAGN_HDR_LEN;
break;
default:
break;
}
if(processed_ip_len > 0) {
/* reassembly is ongoing */
if((frag_size > 0 &&
(frag_size != sicslowpan_len ||
reass_tag != frag_tag ||
!rimeaddr_cmp(&frag_sender, rimebuf_addr(RIMEBUF_ADDR_SENDER)))) ||
frag_size == 0) {
/*
* the packet is a fragment that does not belong to the packet
* being reassembled or the packet is not a fragment.
*/
PRINTF("sicslowpan input: Dropping 6lowpan packet\n");
return;
}
} else {
/*
* reassembly is off
* start it if we received a fragment
*/
if(frag_size > 0){
sicslowpan_len = frag_size;
reass_tag = frag_tag;
timer_set(&reass_timer, SICSLOWPAN_REASS_MAXAGE*CLOCK_SECOND);
PRINTF("sicslowpan input: INIT FRAGMENTATION (len %d, tag %d)\n",
sicslowpan_len, reass_tag);
rimeaddr_copy(&frag_sender, rimebuf_addr(RIMEBUF_ADDR_SENDER));
}
}
if(rime_hdr_len == SICSLOWPAN_FRAGN_HDR_LEN) {
/* this is a FRAGN, skip the header compression dispatch section */
goto copypayload;
}
#endif /* SICSLOWPAN_CONF_FRAG */
/* Process next dispatch and headers */
switch(RIME_HC1_BUF->dispatch) {
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1
case SICSLOWPAN_DISPATCH_HC1:
PRINTF("sicslowpan input: HC1\n");
uncompress_hdr_hc1(frag_size);
break;
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC1*/
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01
case SICSLOWPAN_DISPATCH_IPHC:
PRINTF("sicslowpan input: IPHC\n");
uncompress_hdr_hc01(frag_size);
break;
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01*/
case SICSLOWPAN_DISPATCH_IPV6:
PRINTF("sicslowpan input: IPV6\n");
rime_hdr_len += SICSLOWPAN_IPV6_HDR_LEN;
/* Put uncompressed IP header in sicslowpan_buf. */
memcpy(SICSLOWPAN_IP_BUF, rime_ptr + rime_hdr_len, UIP_IPH_LEN);
/* Update uncomp_hdr_len and rime_hdr_len. */
rime_hdr_len += UIP_IPH_LEN;
uncomp_hdr_len += UIP_IPH_LEN;
break;
default:
/* unknown header */
PRINTF("sicslowpan input: unknown dispatch\n");
return;
}
#if SICSLOWPAN_CONF_FRAG
copypayload:
#endif /*SICSLOWPAN_CONF_FRAG*/
/*
* copy "payload" from the rime buffer to the sicslowpan_buf
* if this is a first fragment or not fragmented packet,
* we have already copied the compressed headers, uncomp_hdr_len
* and rime_hdr_len are non 0, frag_offset is.
* If this is a subsequent fragment, this is the contrary.
*/
rime_payload_len = rimebuf_datalen() - rime_hdr_len;
memcpy((void *)SICSLOWPAN_IP_BUF + uncomp_hdr_len + (u16_t)(frag_offset << 3), rime_ptr + rime_hdr_len, rime_payload_len);
/* update processed_ip_len if fragment, sicslowpan_len otherwise */
#if SICSLOWPAN_CONF_FRAG
if(frag_size > 0){
if(processed_ip_len == 0) {
processed_ip_len += uncomp_hdr_len;
}
processed_ip_len += rime_payload_len;
} else {
#endif /* SICSLOWPAN_CONF_FRAG */
sicslowpan_len = rime_payload_len + uncomp_hdr_len;
#if SICSLOWPAN_CONF_FRAG
}
/*
* If we have a full IP packet in sicslowpan_buf, deliver it to
* the IP stack
*/
if(processed_ip_len == 0 || (processed_ip_len == sicslowpan_len)){
PRINTF("sicslowpan input: IP packet ready (length %d)\n",
sicslowpan_len);
memcpy((void *)UIP_IP_BUF, (void *)SICSLOWPAN_IP_BUF, sicslowpan_len);
uip_len = sicslowpan_len;
sicslowpan_len = 0;
processed_ip_len = 0;
#endif /* SICSLOWPAN_CONF_FRAG */
tcpip_input();
#if SICSLOWPAN_CONF_FRAG
}
#endif /* SICSLOWPAN_CONF_FRAG */
return;
}
/** @} */
/*--------------------------------------------------------------------*/
/* \brief 6lowpan init function (called by the MAC layer) */
/*--------------------------------------------------------------------*/
void
sicslowpan_init(const struct mac_driver *m)
{
/* remember the mac driver */
mac = m;
/* Set our input function as the receive function of the MAC. */
mac->set_receive_function(input);
/*
* Set out output function as the function to be called from uIP to
* send a packet.
*/
tcpip_set_outputfunc(output);
#if SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01
/*
* Initialize the address contexts
* Context 00 is link local context
* Other contexts are NULL at init
*/
addr_contexts[0].used = 1;
addr_contexts[0].number = SICSLOWPAN_IPHC_ADDR_CONTEXT_LL;
addr_contexts[0].prefix[0] = 0xfe;
addr_contexts[0].prefix[1] = 0x80;
addr_contexts[1].used = 1;
addr_contexts[1].number = 1;
addr_contexts[1].prefix[0] = 0xaa;
addr_contexts[1].prefix[1] = 0xaa;
for(i = 2; i < SICSLOWPAN_CONF_MAX_ADDR_CONTEXTS; i++) {
addr_contexts[i].used = 0;
}
#endif /*SICSLOWPAN_CONF_COMPRESSION == SICSLOWPAN_CONF_COMPRESSION_HC01*/
}
/*--------------------------------------------------------------------*/
/** @} */
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