2295 lines
75 KiB
C
2295 lines
75 KiB
C
/**
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* \addtogroup uip6
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* @{
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*/
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/**
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* \file
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* The uIP TCP/IPv6 stack code.
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*
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* \author Adam Dunkels <adam@sics.se>
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* \author Julien Abeille <jabeille@cisco.com> (IPv6 related code)
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* \author Mathilde Durvy <mdurvy@cisco.com> (IPv6 related code)
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*/
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/*
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* Copyright (c) 2001-2003, Adam Dunkels.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote
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* products derived from this software without specific prior
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* written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
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* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
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* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* This file is part of the uIP TCP/IP stack.
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*
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* $Id: uip6.c,v 1.25 2011/01/04 22:11:37 joxe Exp $
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*
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*/
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/*
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* uIP is a small implementation of the IP, UDP and TCP protocols (as
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* well as some basic ICMP stuff). The implementation couples the IP,
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* UDP, TCP and the application layers very tightly. To keep the size
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* of the compiled code down, this code frequently uses the goto
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* statement. While it would be possible to break the uip_process()
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* function into many smaller functions, this would increase the code
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* size because of the overhead of parameter passing and the fact that
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* the optimier would not be as efficient.
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*
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* The principle is that we have a small buffer, called the uip_buf,
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* in which the device driver puts an incoming packet. The TCP/IP
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* stack parses the headers in the packet, and calls the
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* application. If the remote host has sent data to the application,
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* this data is present in the uip_buf and the application read the
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* data from there. It is up to the application to put this data into
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* a byte stream if needed. The application will not be fed with data
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* that is out of sequence.
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*
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* If the application whishes to send data to the peer, it should put
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* its data into the uip_buf. The uip_appdata pointer points to the
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* first available byte. The TCP/IP stack will calculate the
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* checksums, and fill in the necessary header fields and finally send
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* the packet back to the peer.
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*/
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#include "net/uip.h"
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#include "net/uipopt.h"
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#include "net/uip-icmp6.h"
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#include "net/uip-nd6.h"
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#include "net/uip-ds6.h"
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#include <string.h>
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/*---------------------------------------------------------------------------*/
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/* For Debug, logging, statistics */
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/*---------------------------------------------------------------------------*/
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#define DEBUG 0
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#if DEBUG
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#include <stdio.h>
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#define PRINTF(...) printf(__VA_ARGS__)
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#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])
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#define PRINTLLADDR(lladdr) PRINTF(" %02x:%02x:%02x:%02x:%02x:%02x ",lladdr->addr[0], lladdr->addr[1], lladdr->addr[2], lladdr->addr[3],lladdr->addr[4], lladdr->addr[5])
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#else
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#define PRINTF(...)
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#define PRINT6ADDR(addr)
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#endif
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#if UIP_CONF_IPV6_RPL
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#include "rpl/rpl.h"
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#endif /* UIP_CONF_IPV6_RPL */
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#if UIP_LOGGING == 1
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#include <stdio.h>
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void uip_log(char *msg);
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#define UIP_LOG(m) uip_log(m)
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#else
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#define UIP_LOG(m)
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#endif /* UIP_LOGGING == 1 */
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#if UIP_STATISTICS == 1
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struct uip_stats uip_stat;
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#endif /* UIP_STATISTICS == 1 */
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/*---------------------------------------------------------------------------*/
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/** @{ \name Layer 2 variables */
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/*---------------------------------------------------------------------------*/
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/** Host L2 address */
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#if UIP_CONF_LL_802154
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uip_lladdr_t uip_lladdr;
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#else /*UIP_CONF_LL_802154*/
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uip_lladdr_t uip_lladdr = {{0x00,0x06,0x98,0x00,0x02,0x32}};
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#endif /*UIP_CONF_LL_802154*/
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/** @} */
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/*---------------------------------------------------------------------------*/
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/** @{ \name Layer 3 variables */
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/*---------------------------------------------------------------------------*/
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/**
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* \brief Type of the next header in IPv6 header or extension headers
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*
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* Can be the next header field in the IPv6 header or in an extension header.
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* When doing fragment reassembly, we must change the value of the next header
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* field in the header before the fragmentation header, hence we need a pointer
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* to this field.
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*/
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u8_t *uip_next_hdr;
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/** \brief bitmap we use to record which IPv6 headers we have already seen */
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u8_t uip_ext_bitmap = 0;
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/**
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* \brief length of the extension headers read. updated each time we process
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* a header
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*/
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u8_t uip_ext_len = 0;
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/** \brief length of the header options read */
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u8_t uip_ext_opt_offset = 0;
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/** @} */
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/*---------------------------------------------------------------------------*/
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/* Buffers */
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/*---------------------------------------------------------------------------*/
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/** \name Buffer defines
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* @{
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*/
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#define FBUF ((struct uip_tcpip_hdr *)&uip_reassbuf[0])
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#define UIP_IP_BUF ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])
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#define UIP_ICMP_BUF ((struct uip_icmp_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_UDP_BUF ((struct uip_udp_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_TCP_BUF ((struct uip_tcp_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_EXT_BUF ((struct uip_ext_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_ROUTING_BUF ((struct uip_routing_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_FRAG_BUF ((struct uip_frag_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_HBHO_BUF ((struct uip_hbho_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_DESTO_BUF ((struct uip_desto_hdr *)&uip_buf[uip_l2_l3_hdr_len])
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#define UIP_EXT_HDR_OPT_BUF ((struct uip_ext_hdr_opt *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
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#define UIP_EXT_HDR_OPT_PADN_BUF ((struct uip_ext_hdr_opt_padn *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
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#if UIP_CONF_IPV6_RPL
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#define UIP_EXT_HDR_OPT_RPL_BUF ((struct uip_ext_hdr_opt_rpl *)&uip_buf[uip_l2_l3_hdr_len + uip_ext_opt_offset])
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#endif /* UIP_CONF_IPV6_RPL */
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#define UIP_ICMP6_ERROR_BUF ((struct uip_icmp6_error *)&uip_buf[uip_l2_l3_icmp_hdr_len])
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/** @} */
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/** \name Buffer variables
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* @{
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*/
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/** Packet buffer for incoming and outgoing packets */
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#ifndef UIP_CONF_EXTERNAL_BUFFER
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uip_buf_t uip_aligned_buf;
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#endif /* UIP_CONF_EXTERNAL_BUFFER */
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/* The uip_appdata pointer points to application data. */
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void *uip_appdata;
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/* The uip_appdata pointer points to the application data which is to be sent*/
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void *uip_sappdata;
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#if UIP_URGDATA > 0
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/* The uip_urgdata pointer points to urgent data (out-of-band data), if present */
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void *uip_urgdata;
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u16_t uip_urglen, uip_surglen;
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#endif /* UIP_URGDATA > 0 */
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/* The uip_len is either 8 or 16 bits, depending on the maximum packet size.*/
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u16_t uip_len, uip_slen;
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/** @} */
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/*---------------------------------------------------------------------------*/
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/** @{ \name General variables */
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/*---------------------------------------------------------------------------*/
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/* The uip_flags variable is used for communication between the TCP/IP stack
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and the application program. */
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u8_t uip_flags;
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/* uip_conn always points to the current connection (set to NULL for UDP). */
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struct uip_conn *uip_conn;
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/* Temporary variables. */
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#if (UIP_TCP || UIP_UDP)
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static u8_t c;
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#endif
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#if UIP_ACTIVE_OPEN || UIP_UDP
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/* Keeps track of the last port used for a new connection. */
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static u16_t lastport;
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#endif /* UIP_ACTIVE_OPEN || UIP_UDP */
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/** @} */
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/*---------------------------------------------------------------------------*/
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/* TCP */
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/*---------------------------------------------------------------------------*/
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/** \name TCP defines
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*@{
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*/
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/* Structures and definitions. */
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#define TCP_FIN 0x01
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#define TCP_SYN 0x02
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#define TCP_RST 0x04
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#define TCP_PSH 0x08
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#define TCP_ACK 0x10
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#define TCP_URG 0x20
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#define TCP_CTL 0x3f
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#define TCP_OPT_END 0 /* End of TCP options list */
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#define TCP_OPT_NOOP 1 /* "No-operation" TCP option */
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#define TCP_OPT_MSS 2 /* Maximum segment size TCP option */
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#define TCP_OPT_MSS_LEN 4 /* Length of TCP MSS option. */
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/** @} */
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/** \name TCP variables
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*@{
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*/
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#if UIP_TCP
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/* The uip_conns array holds all TCP connections. */
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struct uip_conn uip_conns[UIP_CONNS];
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/* The uip_listenports list all currently listning ports. */
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u16_t uip_listenports[UIP_LISTENPORTS];
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/* The iss variable is used for the TCP initial sequence number. */
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static u8_t iss[4];
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/* Temporary variables. */
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u8_t uip_acc32[4];
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static u8_t opt;
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static u16_t tmp16;
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#endif /* UIP_TCP */
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/** @} */
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/*---------------------------------------------------------------------------*/
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/** @{ \name UDP variables */
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/*---------------------------------------------------------------------------*/
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#if UIP_UDP
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struct uip_udp_conn *uip_udp_conn;
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struct uip_udp_conn uip_udp_conns[UIP_UDP_CONNS];
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#endif /* UIP_UDP */
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/** @} */
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/*---------------------------------------------------------------------------*/
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/** @{ \name ICMPv6 variables */
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/*---------------------------------------------------------------------------*/
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#if UIP_CONF_ICMP6
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/** single possible icmpv6 "connection" */
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struct uip_icmp6_conn uip_icmp6_conns;
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#endif /*UIP_CONF_ICMP6*/
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/*---------------------------------------------------------------------------*/
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/* Functions */
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/*---------------------------------------------------------------------------*/
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#if (!UIP_ARCH_ADD32 && UIP_TCP)
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void
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uip_add32(u8_t *op32, u16_t op16)
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{
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uip_acc32[3] = op32[3] + (op16 & 0xff);
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uip_acc32[2] = op32[2] + (op16 >> 8);
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uip_acc32[1] = op32[1];
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uip_acc32[0] = op32[0];
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if(uip_acc32[2] < (op16 >> 8)) {
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++uip_acc32[1];
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if(uip_acc32[1] == 0) {
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++uip_acc32[0];
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}
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}
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if(uip_acc32[3] < (op16 & 0xff)) {
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++uip_acc32[2];
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if(uip_acc32[2] == 0) {
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++uip_acc32[1];
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if(uip_acc32[1] == 0) {
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++uip_acc32[0];
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}
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}
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}
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}
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#endif /* UIP_ARCH_ADD32 && UIP_TCP */
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#if ! UIP_ARCH_CHKSUM
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/*---------------------------------------------------------------------------*/
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static u16_t
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chksum(u16_t sum, const u8_t *data, u16_t len)
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{
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u16_t t;
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const u8_t *dataptr;
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const u8_t *last_byte;
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dataptr = data;
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last_byte = data + len - 1;
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while(dataptr < last_byte) { /* At least two more bytes */
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t = (dataptr[0] << 8) + dataptr[1];
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sum += t;
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if(sum < t) {
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sum++; /* carry */
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}
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dataptr += 2;
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}
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if(dataptr == last_byte) {
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t = (dataptr[0] << 8) + 0;
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sum += t;
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if(sum < t) {
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sum++; /* carry */
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}
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}
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/* Return sum in host byte order. */
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return sum;
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}
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/*---------------------------------------------------------------------------*/
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u16_t
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uip_chksum(u16_t *data, u16_t len)
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{
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return uip_htons(chksum(0, (u8_t *)data, len));
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}
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/*---------------------------------------------------------------------------*/
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#ifndef UIP_ARCH_IPCHKSUM
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u16_t
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uip_ipchksum(void)
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{
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u16_t sum;
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sum = chksum(0, &uip_buf[UIP_LLH_LEN], UIP_IPH_LEN);
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PRINTF("uip_ipchksum: sum 0x%04x\n", sum);
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return (sum == 0) ? 0xffff : uip_htons(sum);
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}
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#endif
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/*---------------------------------------------------------------------------*/
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static u16_t
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upper_layer_chksum(u8_t proto)
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{
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/* gcc 4.4.0 - 4.6.1 (maybe 4.3...) with -Os on 8 bit CPUS incorrectly compiles:
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* int bar (int);
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* int foo (unsigned char a, unsigned char b) {
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* int len = (a << 8) + b; //len becomes 0xff00&<random>+b
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* return len + bar (len);
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* }
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* upper_layer_len triggers this bug unless it is declared volatile.
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* See https://sourceforge.net/apps/mantisbt/contiki/view.php?id=3
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*/
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volatile u16_t upper_layer_len;
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u16_t sum;
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upper_layer_len = (((u16_t)(UIP_IP_BUF->len[0]) << 8) + UIP_IP_BUF->len[1] - uip_ext_len) ;
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/* First sum pseudoheader. */
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/* IP protocol and length fields. This addition cannot carry. */
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sum = upper_layer_len + proto;
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/* Sum IP source and destination addresses. */
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sum = chksum(sum, (u8_t *)&UIP_IP_BUF->srcipaddr, 2 * sizeof(uip_ipaddr_t));
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/* Sum TCP header and data. */
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sum = chksum(sum, &uip_buf[UIP_IPH_LEN + UIP_LLH_LEN + uip_ext_len],
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upper_layer_len);
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return (sum == 0) ? 0xffff : uip_htons(sum);
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}
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/*---------------------------------------------------------------------------*/
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u16_t
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uip_icmp6chksum(void)
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{
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return upper_layer_chksum(UIP_PROTO_ICMP6);
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}
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/*---------------------------------------------------------------------------*/
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#if UIP_TCP
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u16_t
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uip_tcpchksum(void)
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{
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return upper_layer_chksum(UIP_PROTO_TCP);
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}
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#endif /* UIP_TCP */
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/*---------------------------------------------------------------------------*/
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#if UIP_UDP && UIP_UDP_CHECKSUMS
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u16_t
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uip_udpchksum(void)
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{
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return upper_layer_chksum(UIP_PROTO_UDP);
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}
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#endif /* UIP_UDP && UIP_UDP_CHECKSUMS */
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#endif /* UIP_ARCH_CHKSUM */
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/*---------------------------------------------------------------------------*/
|
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void
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uip_init(void)
|
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{
|
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|
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uip_ds6_init();
|
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|
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#if UIP_TCP
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for(c = 0; c < UIP_LISTENPORTS; ++c) {
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uip_listenports[c] = 0;
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}
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for(c = 0; c < UIP_CONNS; ++c) {
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uip_conns[c].tcpstateflags = UIP_CLOSED;
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}
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#endif /* UIP_TCP */
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#if UIP_ACTIVE_OPEN || UIP_UDP
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lastport = 1024;
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#endif /* UIP_ACTIVE_OPEN || UIP_UDP */
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|
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#if UIP_UDP
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for(c = 0; c < UIP_UDP_CONNS; ++c) {
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uip_udp_conns[c].lport = 0;
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}
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#endif /* UIP_UDP */
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}
|
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/*---------------------------------------------------------------------------*/
|
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#if UIP_TCP && UIP_ACTIVE_OPEN
|
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struct uip_conn *
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uip_connect(uip_ipaddr_t *ripaddr, u16_t rport)
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{
|
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register struct uip_conn *conn, *cconn;
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|
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/* Find an unused local port. */
|
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again:
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++lastport;
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|
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if(lastport >= 32000) {
|
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lastport = 4096;
|
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}
|
|
|
|
/* Check if this port is already in use, and if so try to find
|
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another one. */
|
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for(c = 0; c < UIP_CONNS; ++c) {
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conn = &uip_conns[c];
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if(conn->tcpstateflags != UIP_CLOSED &&
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conn->lport == uip_htons(lastport)) {
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goto again;
|
|
}
|
|
}
|
|
|
|
conn = 0;
|
|
for(c = 0; c < UIP_CONNS; ++c) {
|
|
cconn = &uip_conns[c];
|
|
if(cconn->tcpstateflags == UIP_CLOSED) {
|
|
conn = cconn;
|
|
break;
|
|
}
|
|
if(cconn->tcpstateflags == UIP_TIME_WAIT) {
|
|
if(conn == 0 ||
|
|
cconn->timer > conn->timer) {
|
|
conn = cconn;
|
|
}
|
|
}
|
|
}
|
|
|
|
if(conn == 0) {
|
|
return 0;
|
|
}
|
|
|
|
conn->tcpstateflags = UIP_SYN_SENT;
|
|
|
|
conn->snd_nxt[0] = iss[0];
|
|
conn->snd_nxt[1] = iss[1];
|
|
conn->snd_nxt[2] = iss[2];
|
|
conn->snd_nxt[3] = iss[3];
|
|
|
|
conn->rcv_nxt[0] = 0;
|
|
conn->rcv_nxt[1] = 0;
|
|
conn->rcv_nxt[2] = 0;
|
|
conn->rcv_nxt[3] = 0;
|
|
|
|
conn->initialmss = conn->mss = UIP_TCP_MSS;
|
|
|
|
conn->len = 1; /* TCP length of the SYN is one. */
|
|
conn->nrtx = 0;
|
|
conn->timer = 1; /* Send the SYN next time around. */
|
|
conn->rto = UIP_RTO;
|
|
conn->sa = 0;
|
|
conn->sv = 16; /* Initial value of the RTT variance. */
|
|
conn->lport = uip_htons(lastport);
|
|
conn->rport = rport;
|
|
uip_ipaddr_copy(&conn->ripaddr, ripaddr);
|
|
|
|
return conn;
|
|
}
|
|
#endif /* UIP_TCP && UIP_ACTIVE_OPEN */
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
remove_ext_hdr(void)
|
|
{
|
|
/* Remove ext header before TCP/UDP processing. */
|
|
if(uip_ext_len > 0) {
|
|
PRINTF("Cutting ext-header before TCP send (%d)\n", uip_ext_len);
|
|
memmove(((uint8_t *)UIP_TCP_BUF) - uip_ext_len, (uint8_t *)UIP_TCP_BUF,
|
|
uip_len - UIP_IPH_LEN - uip_ext_len);
|
|
|
|
uip_len -= uip_ext_len;
|
|
|
|
/* Update the IP length. */
|
|
UIP_IP_BUF->len[0] = (uip_len - UIP_IPH_LEN) >> 8;
|
|
UIP_IP_BUF->len[1] = (uip_len - UIP_IPH_LEN) & 0xff;
|
|
uip_ext_len = 0;
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
#if UIP_UDP
|
|
struct uip_udp_conn *
|
|
uip_udp_new(const uip_ipaddr_t *ripaddr, u16_t rport)
|
|
{
|
|
register struct uip_udp_conn *conn;
|
|
|
|
/* Find an unused local port. */
|
|
again:
|
|
++lastport;
|
|
|
|
if(lastport >= 32000) {
|
|
lastport = 4096;
|
|
}
|
|
|
|
for(c = 0; c < UIP_UDP_CONNS; ++c) {
|
|
if(uip_udp_conns[c].lport == uip_htons(lastport)) {
|
|
goto again;
|
|
}
|
|
}
|
|
|
|
conn = 0;
|
|
for(c = 0; c < UIP_UDP_CONNS; ++c) {
|
|
if(uip_udp_conns[c].lport == 0) {
|
|
conn = &uip_udp_conns[c];
|
|
break;
|
|
}
|
|
}
|
|
|
|
if(conn == 0) {
|
|
return 0;
|
|
}
|
|
|
|
conn->lport = UIP_HTONS(lastport);
|
|
conn->rport = rport;
|
|
if(ripaddr == NULL) {
|
|
memset(&conn->ripaddr, 0, sizeof(uip_ipaddr_t));
|
|
} else {
|
|
uip_ipaddr_copy(&conn->ripaddr, ripaddr);
|
|
}
|
|
conn->ttl = uip_ds6_if.cur_hop_limit;
|
|
|
|
return conn;
|
|
}
|
|
#endif /* UIP_UDP */
|
|
/*---------------------------------------------------------------------------*/
|
|
#if UIP_TCP
|
|
void
|
|
uip_unlisten(u16_t port)
|
|
{
|
|
for(c = 0; c < UIP_LISTENPORTS; ++c) {
|
|
if(uip_listenports[c] == port) {
|
|
uip_listenports[c] = 0;
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
uip_listen(u16_t port)
|
|
{
|
|
for(c = 0; c < UIP_LISTENPORTS; ++c) {
|
|
if(uip_listenports[c] == 0) {
|
|
uip_listenports[c] = port;
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
#if UIP_CONF_IPV6_REASSEMBLY
|
|
#define UIP_REASS_BUFSIZE (UIP_BUFSIZE - UIP_LLH_LEN)
|
|
|
|
static u8_t uip_reassbuf[UIP_REASS_BUFSIZE];
|
|
|
|
static u8_t uip_reassbitmap[UIP_REASS_BUFSIZE / (8 * 8)];
|
|
/*the first byte of an IP fragment is aligned on an 8-byte boundary */
|
|
|
|
static const u8_t bitmap_bits[8] = {0xff, 0x7f, 0x3f, 0x1f,
|
|
0x0f, 0x07, 0x03, 0x01};
|
|
static u16_t uip_reasslen;
|
|
static u8_t uip_reassflags;
|
|
|
|
#define UIP_REASS_FLAG_LASTFRAG 0x01
|
|
#define UIP_REASS_FLAG_FIRSTFRAG 0x02
|
|
#define UIP_REASS_FLAG_ERROR_MSG 0x04
|
|
|
|
|
|
/*
|
|
* See RFC 2460 for a description of fragmentation in IPv6
|
|
* A typical Ipv6 fragment
|
|
* +------------------+--------+--------------+
|
|
* | Unfragmentable |Fragment| first |
|
|
* | Part | Header | fragment |
|
|
* +------------------+--------+--------------+
|
|
*/
|
|
|
|
|
|
struct etimer uip_reass_timer; /* timer for reassembly */
|
|
u8_t uip_reass_on; /* equal to 1 if we are currently reassembling a packet */
|
|
|
|
static u32_t uip_id; /* For every packet that is to be fragmented, the source
|
|
node generates an Identification value that is present
|
|
in all the fragments */
|
|
#define IP_MF 0x0001
|
|
|
|
static u16_t
|
|
uip_reass(void)
|
|
{
|
|
u16_t offset=0;
|
|
u16_t len;
|
|
u16_t i;
|
|
|
|
/* If ip_reasstmr is zero, no packet is present in the buffer */
|
|
/* We first write the unfragmentable part of IP header into the reassembly
|
|
buffer. The reset the other reassembly variables. */
|
|
if(uip_reass_on == 0) {
|
|
PRINTF("Starting reassembly\n");
|
|
memcpy(FBUF, UIP_IP_BUF, uip_ext_len + UIP_IPH_LEN);
|
|
/* temporary in case we do not receive the fragment with offset 0 first */
|
|
etimer_set(&uip_reass_timer, UIP_REASS_MAXAGE*CLOCK_SECOND);
|
|
uip_reass_on = 1;
|
|
uip_reassflags = 0;
|
|
uip_id = UIP_FRAG_BUF->id;
|
|
/* Clear the bitmap. */
|
|
memset(uip_reassbitmap, 0, sizeof(uip_reassbitmap));
|
|
}
|
|
/*
|
|
* Check if the incoming fragment matches the one currently present
|
|
* in the reasembly buffer. If so, we proceed with copying the fragment
|
|
* into the buffer.
|
|
*/
|
|
if(uip_ipaddr_cmp(&FBUF->srcipaddr, &UIP_IP_BUF->srcipaddr) &&
|
|
uip_ipaddr_cmp(&FBUF->destipaddr, &UIP_IP_BUF->destipaddr) &&
|
|
UIP_FRAG_BUF->id == uip_id) {
|
|
len = uip_len - uip_ext_len - UIP_IPH_LEN - UIP_FRAGH_LEN;
|
|
offset = (uip_ntohs(UIP_FRAG_BUF->offsetresmore) & 0xfff8);
|
|
/* in byte, originaly in multiple of 8 bytes*/
|
|
PRINTF("len %d\n", len);
|
|
PRINTF("offset %d\n", offset);
|
|
if(offset == 0){
|
|
uip_reassflags |= UIP_REASS_FLAG_FIRSTFRAG;
|
|
/*
|
|
* The Next Header field of the last header of the Unfragmentable
|
|
* Part is obtained from the Next Header field of the first
|
|
* fragment's Fragment header.
|
|
*/
|
|
*uip_next_hdr = UIP_FRAG_BUF->next;
|
|
memcpy(FBUF, UIP_IP_BUF, uip_ext_len + UIP_IPH_LEN);
|
|
PRINTF("src ");
|
|
PRINT6ADDR(&FBUF->srcipaddr);
|
|
PRINTF("dest ");
|
|
PRINT6ADDR(&FBUF->destipaddr);
|
|
PRINTF("next %d\n", UIP_IP_BUF->proto);
|
|
|
|
}
|
|
|
|
/* If the offset or the offset + fragment length overflows the
|
|
reassembly buffer, we discard the entire packet. */
|
|
if(offset > UIP_REASS_BUFSIZE ||
|
|
offset + len > UIP_REASS_BUFSIZE) {
|
|
uip_reass_on = 0;
|
|
etimer_stop(&uip_reass_timer);
|
|
return 0;
|
|
}
|
|
|
|
/* If this fragment has the More Fragments flag set to zero, it is the
|
|
last fragment*/
|
|
if((uip_ntohs(UIP_FRAG_BUF->offsetresmore) & IP_MF) == 0) {
|
|
uip_reassflags |= UIP_REASS_FLAG_LASTFRAG;
|
|
/*calculate the size of the entire packet*/
|
|
uip_reasslen = offset + len;
|
|
PRINTF("LAST FRAGMENT reasslen %d\n", uip_reasslen);
|
|
} else {
|
|
/* If len is not a multiple of 8 octets and the M flag of that fragment
|
|
is 1, then that fragment must be discarded and an ICMP Parameter
|
|
Problem, Code 0, message should be sent to the source of the fragment,
|
|
pointing to the Payload Length field of the fragment packet. */
|
|
if(len % 8 != 0){
|
|
uip_icmp6_error_output(ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, 4);
|
|
uip_reassflags |= UIP_REASS_FLAG_ERROR_MSG;
|
|
/* not clear if we should interrupt reassembly, but it seems so from
|
|
the conformance tests */
|
|
uip_reass_on = 0;
|
|
etimer_stop(&uip_reass_timer);
|
|
return uip_len;
|
|
}
|
|
}
|
|
|
|
/* Copy the fragment into the reassembly buffer, at the right
|
|
offset. */
|
|
memcpy((uint8_t *)FBUF + UIP_IPH_LEN + uip_ext_len + offset,
|
|
(uint8_t *)UIP_FRAG_BUF + UIP_FRAGH_LEN, len);
|
|
|
|
/* Update the bitmap. */
|
|
if(offset >> 6 == (offset + len) >> 6) {
|
|
uip_reassbitmap[offset >> 6] |=
|
|
bitmap_bits[(offset >> 3) & 7] &
|
|
~bitmap_bits[((offset + len) >> 3) & 7];
|
|
} else {
|
|
/* If the two endpoints are in different bytes, we update the
|
|
bytes in the endpoints and fill the stuff inbetween with
|
|
0xff. */
|
|
uip_reassbitmap[offset >> 6] |= bitmap_bits[(offset >> 3) & 7];
|
|
|
|
for(i = (1 + (offset >> 6)); i < ((offset + len) >> 6); ++i) {
|
|
uip_reassbitmap[i] = 0xff;
|
|
}
|
|
uip_reassbitmap[(offset + len) >> 6] |=
|
|
~bitmap_bits[((offset + len) >> 3) & 7];
|
|
}
|
|
|
|
/* Finally, we check if we have a full packet in the buffer. We do
|
|
this by checking if we have the last fragment and if all bits
|
|
in the bitmap are set. */
|
|
|
|
if(uip_reassflags & UIP_REASS_FLAG_LASTFRAG) {
|
|
/* Check all bytes up to and including all but the last byte in
|
|
the bitmap. */
|
|
for(i = 0; i < (uip_reasslen >> 6); ++i) {
|
|
if(uip_reassbitmap[i] != 0xff) {
|
|
return 0;
|
|
}
|
|
}
|
|
/* Check the last byte in the bitmap. It should contain just the
|
|
right amount of bits. */
|
|
if(uip_reassbitmap[uip_reasslen >> 6] !=
|
|
(u8_t)~bitmap_bits[(uip_reasslen >> 3) & 7]) {
|
|
return 0;
|
|
}
|
|
|
|
/* If we have come this far, we have a full packet in the
|
|
buffer, so we copy it to uip_buf. We also reset the timer. */
|
|
uip_reass_on = 0;
|
|
etimer_stop(&uip_reass_timer);
|
|
|
|
uip_reasslen += UIP_IPH_LEN + uip_ext_len;
|
|
memcpy(UIP_IP_BUF, FBUF, uip_reasslen);
|
|
UIP_IP_BUF->len[0] = ((uip_reasslen - UIP_IPH_LEN) >> 8);
|
|
UIP_IP_BUF->len[1] = ((uip_reasslen - UIP_IPH_LEN) & 0xff);
|
|
PRINTF("REASSEMBLED PAQUET %d (%d)\n", uip_reasslen,
|
|
(UIP_IP_BUF->len[0] << 8) | UIP_IP_BUF->len[1]);
|
|
|
|
return uip_reasslen;
|
|
|
|
}
|
|
} else {
|
|
PRINTF("Already reassembling another paquet\n");
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
uip_reass_over(void)
|
|
{
|
|
/* to late, we abandon the reassembly of the packet */
|
|
|
|
uip_reass_on = 0;
|
|
etimer_stop(&uip_reass_timer);
|
|
|
|
if(uip_reassflags & UIP_REASS_FLAG_FIRSTFRAG){
|
|
PRINTF("FRAG INTERRUPTED TOO LATE\n");
|
|
/* If the first fragment has been received, an ICMP Time Exceeded
|
|
-- Fragment Reassembly Time Exceeded message should be sent to the
|
|
source of that fragment. */
|
|
/** \note
|
|
* We don't have a complete packet to put in the error message.
|
|
* We could include the first fragment but since its not mandated by
|
|
* any RFC, we decided not to include it as it reduces the size of
|
|
* the packet.
|
|
*/
|
|
uip_len = 0;
|
|
uip_ext_len = 0;
|
|
memcpy(UIP_IP_BUF, FBUF, UIP_IPH_LEN); /* copy the header for src
|
|
and dest address*/
|
|
uip_icmp6_error_output(ICMP6_TIME_EXCEEDED, ICMP6_TIME_EXCEED_REASSEMBLY, 0);
|
|
|
|
UIP_STAT(++uip_stat.ip.sent);
|
|
uip_flags = 0;
|
|
}
|
|
}
|
|
|
|
#endif /* UIP_CONF_IPV6_REASSEMBLY */
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
#if UIP_TCP
|
|
static void
|
|
uip_add_rcv_nxt(u16_t n)
|
|
{
|
|
uip_add32(uip_conn->rcv_nxt, n);
|
|
uip_conn->rcv_nxt[0] = uip_acc32[0];
|
|
uip_conn->rcv_nxt[1] = uip_acc32[1];
|
|
uip_conn->rcv_nxt[2] = uip_acc32[2];
|
|
uip_conn->rcv_nxt[3] = uip_acc32[3];
|
|
}
|
|
#endif
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* \brief Process the options in Destination and Hop By Hop extension headers
|
|
*/
|
|
static u8_t
|
|
ext_hdr_options_process(void)
|
|
{
|
|
/*
|
|
* Length field in the extension header: length of the header in units of
|
|
* 8 bytes, excluding the first 8 bytes
|
|
* length field in an option : the length of data in the option
|
|
*/
|
|
uip_ext_opt_offset = 2;
|
|
while(uip_ext_opt_offset < ((UIP_EXT_BUF->len << 3) + 8)) {
|
|
switch(UIP_EXT_HDR_OPT_BUF->type) {
|
|
/*
|
|
* for now we do not support any options except padding ones
|
|
* PAD1 does not make sense as the header must be 8bytes aligned,
|
|
* hence we can only have
|
|
*/
|
|
case UIP_EXT_HDR_OPT_PAD1:
|
|
PRINTF("Processing PAD1 option\n");
|
|
uip_ext_opt_offset += 1;
|
|
break;
|
|
case UIP_EXT_HDR_OPT_PADN:
|
|
PRINTF("Processing PADN option\n");
|
|
uip_ext_opt_offset += UIP_EXT_HDR_OPT_PADN_BUF->opt_len + 2;
|
|
break;
|
|
#if UIP_CONF_IPV6_RPL
|
|
case UIP_EXT_HDR_OPT_RPL:
|
|
PRINTF("Processing RPL option\n");
|
|
if(rpl_verify_header(uip_ext_opt_offset)) {
|
|
PRINTF("RPL Option Error : Dropping Packet");
|
|
return 1;
|
|
}
|
|
uip_ext_opt_offset += (UIP_EXT_HDR_OPT_RPL_BUF->opt_len) + 2;
|
|
return 0;
|
|
#endif /* UIP_CONF_IPV6_RPL */
|
|
default:
|
|
/*
|
|
* check the two highest order bits of the option
|
|
* - 00 skip over this option and continue processing the header.
|
|
* - 01 discard the packet.
|
|
* - 10 discard the packet and, regardless of whether or not the
|
|
* packet's Destination Address was a multicast address, send an
|
|
* ICMP Parameter Problem, Code 2, message to the packet's
|
|
* Source Address, pointing to the unrecognized Option Type.
|
|
* - 11 discard the packet and, only if the packet's Destination
|
|
* Address was not a multicast address, send an ICMP Parameter
|
|
* Problem, Code 2, message to the packet's Source Address,
|
|
* pointing to the unrecognized Option Type.
|
|
*/
|
|
PRINTF("MSB %x\n", UIP_EXT_HDR_OPT_BUF->type);
|
|
switch(UIP_EXT_HDR_OPT_BUF->type & 0xC0) {
|
|
case 0:
|
|
break;
|
|
case 0x40:
|
|
return 1;
|
|
case 0xC0:
|
|
if(uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
|
|
return 1;
|
|
}
|
|
case 0x80:
|
|
uip_icmp6_error_output(ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION,
|
|
(u32_t)UIP_IPH_LEN + uip_ext_len + uip_ext_opt_offset);
|
|
return 2;
|
|
}
|
|
/* in the cases were we did not discard, update ext_opt* */
|
|
uip_ext_opt_offset += UIP_EXT_HDR_OPT_BUF->len + 2;
|
|
break;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
uip_process(u8_t flag)
|
|
{
|
|
#if UIP_TCP
|
|
register struct uip_conn *uip_connr = uip_conn;
|
|
#endif /* UIP_TCP */
|
|
#if UIP_UDP
|
|
if(flag == UIP_UDP_SEND_CONN) {
|
|
goto udp_send;
|
|
}
|
|
#endif /* UIP_UDP */
|
|
uip_sappdata = uip_appdata = &uip_buf[UIP_IPTCPH_LEN + UIP_LLH_LEN];
|
|
|
|
/* Check if we were invoked because of a poll request for a
|
|
particular connection. */
|
|
if(flag == UIP_POLL_REQUEST) {
|
|
#if UIP_TCP
|
|
if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED &&
|
|
!uip_outstanding(uip_connr)) {
|
|
uip_flags = UIP_POLL;
|
|
UIP_APPCALL();
|
|
goto appsend;
|
|
#if UIP_ACTIVE_OPEN
|
|
} else if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) {
|
|
/* In the SYN_SENT state, we retransmit out SYN. */
|
|
UIP_TCP_BUF->flags = 0;
|
|
goto tcp_send_syn;
|
|
#endif /* UIP_ACTIVE_OPEN */
|
|
}
|
|
goto drop;
|
|
#endif /* UIP_TCP */
|
|
/* Check if we were invoked because of the perodic timer fireing. */
|
|
} else if(flag == UIP_TIMER) {
|
|
/* Reset the length variables. */
|
|
#if UIP_TCP
|
|
uip_len = 0;
|
|
uip_slen = 0;
|
|
|
|
/* Increase the initial sequence number. */
|
|
if(++iss[3] == 0) {
|
|
if(++iss[2] == 0) {
|
|
if(++iss[1] == 0) {
|
|
++iss[0];
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check if the connection is in a state in which we simply wait
|
|
* for the connection to time out. If so, we increase the
|
|
* connection's timer and remove the connection if it times
|
|
* out.
|
|
*/
|
|
if(uip_connr->tcpstateflags == UIP_TIME_WAIT ||
|
|
uip_connr->tcpstateflags == UIP_FIN_WAIT_2) {
|
|
++(uip_connr->timer);
|
|
if(uip_connr->timer == UIP_TIME_WAIT_TIMEOUT) {
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
|
}
|
|
} else if(uip_connr->tcpstateflags != UIP_CLOSED) {
|
|
/*
|
|
* If the connection has outstanding data, we increase the
|
|
* connection's timer and see if it has reached the RTO value
|
|
* in which case we retransmit.
|
|
*/
|
|
if(uip_outstanding(uip_connr)) {
|
|
if(uip_connr->timer-- == 0) {
|
|
if(uip_connr->nrtx == UIP_MAXRTX ||
|
|
((uip_connr->tcpstateflags == UIP_SYN_SENT ||
|
|
uip_connr->tcpstateflags == UIP_SYN_RCVD) &&
|
|
uip_connr->nrtx == UIP_MAXSYNRTX)) {
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
|
|
|
/*
|
|
* We call UIP_APPCALL() with uip_flags set to
|
|
* UIP_TIMEDOUT to inform the application that the
|
|
* connection has timed out.
|
|
*/
|
|
uip_flags = UIP_TIMEDOUT;
|
|
UIP_APPCALL();
|
|
|
|
/* We also send a reset packet to the remote host. */
|
|
UIP_TCP_BUF->flags = TCP_RST | TCP_ACK;
|
|
goto tcp_send_nodata;
|
|
}
|
|
|
|
/* Exponential backoff. */
|
|
uip_connr->timer = UIP_RTO << (uip_connr->nrtx > 4?
|
|
4:
|
|
uip_connr->nrtx);
|
|
++(uip_connr->nrtx);
|
|
|
|
/*
|
|
* Ok, so we need to retransmit. We do this differently
|
|
* depending on which state we are in. In ESTABLISHED, we
|
|
* call upon the application so that it may prepare the
|
|
* data for the retransmit. In SYN_RCVD, we resend the
|
|
* SYNACK that we sent earlier and in LAST_ACK we have to
|
|
* retransmit our FINACK.
|
|
*/
|
|
UIP_STAT(++uip_stat.tcp.rexmit);
|
|
switch(uip_connr->tcpstateflags & UIP_TS_MASK) {
|
|
case UIP_SYN_RCVD:
|
|
/* In the SYN_RCVD state, we should retransmit our SYNACK. */
|
|
goto tcp_send_synack;
|
|
|
|
#if UIP_ACTIVE_OPEN
|
|
case UIP_SYN_SENT:
|
|
/* In the SYN_SENT state, we retransmit out SYN. */
|
|
UIP_TCP_BUF->flags = 0;
|
|
goto tcp_send_syn;
|
|
#endif /* UIP_ACTIVE_OPEN */
|
|
|
|
case UIP_ESTABLISHED:
|
|
/*
|
|
* In the ESTABLISHED state, we call upon the application
|
|
* to do the actual retransmit after which we jump into
|
|
* the code for sending out the packet (the apprexmit
|
|
* label).
|
|
*/
|
|
uip_flags = UIP_REXMIT;
|
|
UIP_APPCALL();
|
|
goto apprexmit;
|
|
|
|
case UIP_FIN_WAIT_1:
|
|
case UIP_CLOSING:
|
|
case UIP_LAST_ACK:
|
|
/* In all these states we should retransmit a FINACK. */
|
|
goto tcp_send_finack;
|
|
}
|
|
}
|
|
} else if((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED) {
|
|
/*
|
|
* If there was no need for a retransmission, we poll the
|
|
* application for new data.
|
|
*/
|
|
uip_flags = UIP_POLL;
|
|
UIP_APPCALL();
|
|
goto appsend;
|
|
}
|
|
}
|
|
goto drop;
|
|
#endif /* UIP_TCP */
|
|
}
|
|
#if UIP_UDP
|
|
if(flag == UIP_UDP_TIMER) {
|
|
if(uip_udp_conn->lport != 0) {
|
|
uip_conn = NULL;
|
|
uip_sappdata = uip_appdata = &uip_buf[uip_l2_l3_udp_hdr_len];
|
|
uip_len = uip_slen = 0;
|
|
uip_flags = UIP_POLL;
|
|
UIP_UDP_APPCALL();
|
|
goto udp_send;
|
|
} else {
|
|
goto drop;
|
|
}
|
|
}
|
|
#endif /* UIP_UDP */
|
|
|
|
|
|
/* This is where the input processing starts. */
|
|
UIP_STAT(++uip_stat.ip.recv);
|
|
|
|
/* Start of IP input header processing code. */
|
|
|
|
/* Check validity of the IP header. */
|
|
if((UIP_IP_BUF->vtc & 0xf0) != 0x60) { /* IP version and header length. */
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
UIP_STAT(++uip_stat.ip.vhlerr);
|
|
UIP_LOG("ipv6: invalid version.");
|
|
goto drop;
|
|
}
|
|
/*
|
|
* Check the size of the packet. If the size reported to us in
|
|
* uip_len is smaller the size reported in the IP header, we assume
|
|
* that the packet has been corrupted in transit. If the size of
|
|
* uip_len is larger than the size reported in the IP packet header,
|
|
* the packet has been padded and we set uip_len to the correct
|
|
* value..
|
|
*/
|
|
|
|
if((UIP_IP_BUF->len[0] << 8) + UIP_IP_BUF->len[1] <= uip_len) {
|
|
uip_len = (UIP_IP_BUF->len[0] << 8) + UIP_IP_BUF->len[1] + UIP_IPH_LEN;
|
|
/*
|
|
* The length reported in the IPv6 header is the
|
|
* length of the payload that follows the
|
|
* header. However, uIP uses the uip_len variable
|
|
* for holding the size of the entire packet,
|
|
* including the IP header. For IPv4 this is not a
|
|
* problem as the length field in the IPv4 header
|
|
* contains the length of the entire packet. But
|
|
* for IPv6 we need to add the size of the IPv6
|
|
* header (40 bytes).
|
|
*/
|
|
} else {
|
|
UIP_LOG("ip: packet shorter than reported in IP header.");
|
|
goto drop;
|
|
}
|
|
|
|
PRINTF("IPv6 packet received from ");
|
|
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
|
|
PRINTF(" to ");
|
|
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
|
|
PRINTF("\n");
|
|
|
|
if(uip_is_addr_mcast(&UIP_IP_BUF->srcipaddr)){
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
PRINTF("Dropping packet, src is mcast\n");
|
|
goto drop;
|
|
}
|
|
|
|
#if UIP_CONF_ROUTER
|
|
/*
|
|
* Next header field processing. In IPv6, we can have extension headers,
|
|
* if present, the Hop-by-Hop Option must be processed before forwarding
|
|
* the packet.
|
|
*/
|
|
uip_next_hdr = &UIP_IP_BUF->proto;
|
|
uip_ext_len = 0;
|
|
uip_ext_bitmap = 0;
|
|
if(*uip_next_hdr == UIP_PROTO_HBHO) {
|
|
#if UIP_CONF_IPV6_CHECKS
|
|
uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_HBHO;
|
|
#endif /*UIP_CONF_IPV6_CHECKS*/
|
|
switch(ext_hdr_options_process()) {
|
|
case 0:
|
|
/*continue*/
|
|
uip_next_hdr = &UIP_EXT_BUF->next;
|
|
uip_ext_len += (UIP_EXT_BUF->len << 3) + 8;
|
|
break;
|
|
case 1:
|
|
/*silently discard*/
|
|
goto drop;
|
|
case 2:
|
|
/* send icmp error message (created in ext_hdr_options_process)
|
|
* and discard*/
|
|
goto send;
|
|
}
|
|
}
|
|
|
|
|
|
/* TBD Some Parameter problem messages */
|
|
if(!uip_ds6_is_my_addr(&UIP_IP_BUF->destipaddr) &&
|
|
!uip_ds6_is_my_maddr(&UIP_IP_BUF->destipaddr)) {
|
|
if(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr) &&
|
|
!uip_is_addr_link_local(&UIP_IP_BUF->destipaddr) &&
|
|
!uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr) &&
|
|
!uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr) &&
|
|
!uip_is_addr_loopback(&UIP_IP_BUF->destipaddr)) {
|
|
|
|
|
|
/* Check MTU */
|
|
if(uip_len > UIP_LINK_MTU) {
|
|
uip_icmp6_error_output(ICMP6_PACKET_TOO_BIG, 0, UIP_LINK_MTU);
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
goto send;
|
|
}
|
|
/* Check Hop Limit */
|
|
if(UIP_IP_BUF->ttl <= 1) {
|
|
uip_icmp6_error_output(ICMP6_TIME_EXCEEDED,
|
|
ICMP6_TIME_EXCEED_TRANSIT, 0);
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
goto send;
|
|
}
|
|
|
|
#if UIP_CONF_IPV6_RPL
|
|
rpl_update_header_empty();
|
|
#endif /* UIP_CONF_IPV6_RPL */
|
|
|
|
UIP_IP_BUF->ttl = UIP_IP_BUF->ttl - 1;
|
|
PRINTF("Forwarding packet to ");
|
|
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
|
|
PRINTF("\n");
|
|
UIP_STAT(++uip_stat.ip.forwarded);
|
|
goto send;
|
|
} else {
|
|
if((uip_is_addr_link_local(&UIP_IP_BUF->srcipaddr)) &&
|
|
(!uip_is_addr_unspecified(&UIP_IP_BUF->srcipaddr)) &&
|
|
(!uip_is_addr_loopback(&UIP_IP_BUF->destipaddr)) &&
|
|
(!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) &&
|
|
(!uip_ds6_is_addr_onlink((&UIP_IP_BUF->destipaddr)))) {
|
|
PRINTF("LL source address with off link destination, dropping\n");
|
|
uip_icmp6_error_output(ICMP6_DST_UNREACH,
|
|
ICMP6_DST_UNREACH_NOTNEIGHBOR, 0);
|
|
goto send;
|
|
}
|
|
PRINTF("Dropping packet, not for me and link local or multicast\n");
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
goto drop;
|
|
}
|
|
}
|
|
#else /* UIP_CONF_ROUTER */
|
|
if(!uip_ds6_is_my_addr(&UIP_IP_BUF->destipaddr) &&
|
|
!uip_ds6_is_my_maddr(&UIP_IP_BUF->destipaddr) &&
|
|
!uip_is_addr_mcast(&UIP_IP_BUF->destipaddr)) {
|
|
PRINTF("Dropping packet, not for me\n");
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
goto drop;
|
|
}
|
|
|
|
/*
|
|
* Next header field processing. In IPv6, we can have extension headers,
|
|
* they are processed here
|
|
*/
|
|
uip_next_hdr = &UIP_IP_BUF->proto;
|
|
uip_ext_len = 0;
|
|
uip_ext_bitmap = 0;
|
|
#endif /* UIP_CONF_ROUTER */
|
|
|
|
while(1) {
|
|
switch(*uip_next_hdr){
|
|
#if UIP_TCP
|
|
case UIP_PROTO_TCP:
|
|
/* TCP, for both IPv4 and IPv6 */
|
|
goto tcp_input;
|
|
#endif /* UIP_TCP */
|
|
#if UIP_UDP
|
|
case UIP_PROTO_UDP:
|
|
/* UDP, for both IPv4 and IPv6 */
|
|
goto udp_input;
|
|
#endif /* UIP_UDP */
|
|
case UIP_PROTO_ICMP6:
|
|
/* ICMPv6 */
|
|
goto icmp6_input;
|
|
case UIP_PROTO_HBHO:
|
|
PRINTF("Processing hbh header\n");
|
|
/* Hop by hop option header */
|
|
#if UIP_CONF_IPV6_CHECKS
|
|
/* Hop by hop option header. If we saw one HBH already, drop */
|
|
if(uip_ext_bitmap & UIP_EXT_HDR_BITMAP_HBHO) {
|
|
goto bad_hdr;
|
|
} else {
|
|
uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_HBHO;
|
|
}
|
|
#endif /*UIP_CONF_IPV6_CHECKS*/
|
|
switch(ext_hdr_options_process()) {
|
|
case 0:
|
|
/*continue*/
|
|
uip_next_hdr = &UIP_EXT_BUF->next;
|
|
uip_ext_len += (UIP_EXT_BUF->len << 3) + 8;
|
|
break;
|
|
case 1:
|
|
/*silently discard*/
|
|
goto drop;
|
|
case 2:
|
|
/* send icmp error message (created in ext_hdr_options_process)
|
|
* and discard*/
|
|
goto send;
|
|
}
|
|
break;
|
|
case UIP_PROTO_DESTO:
|
|
#if UIP_CONF_IPV6_CHECKS
|
|
/* Destination option header. if we saw two already, drop */
|
|
PRINTF("Processing desto header\n");
|
|
if(uip_ext_bitmap & UIP_EXT_HDR_BITMAP_DESTO1) {
|
|
if(uip_ext_bitmap & UIP_EXT_HDR_BITMAP_DESTO2) {
|
|
goto bad_hdr;
|
|
} else{
|
|
uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_DESTO2;
|
|
}
|
|
} else {
|
|
uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_DESTO1;
|
|
}
|
|
#endif /*UIP_CONF_IPV6_CHECKS*/
|
|
switch(ext_hdr_options_process()) {
|
|
case 0:
|
|
/*continue*/
|
|
uip_next_hdr = &UIP_EXT_BUF->next;
|
|
uip_ext_len += (UIP_EXT_BUF->len << 3) + 8;
|
|
break;
|
|
case 1:
|
|
/*silently discard*/
|
|
goto drop;
|
|
case 2:
|
|
/* send icmp error message (created in ext_hdr_options_process)
|
|
* and discard*/
|
|
goto send;
|
|
}
|
|
break;
|
|
case UIP_PROTO_ROUTING:
|
|
#if UIP_CONF_IPV6_CHECKS
|
|
/* Routing header. If we saw one already, drop */
|
|
if(uip_ext_bitmap & UIP_EXT_HDR_BITMAP_ROUTING) {
|
|
goto bad_hdr;
|
|
} else {
|
|
uip_ext_bitmap |= UIP_EXT_HDR_BITMAP_ROUTING;
|
|
}
|
|
#endif /*UIP_CONF_IPV6_CHECKS*/
|
|
/*
|
|
* Routing Header length field is in units of 8 bytes, excluding
|
|
* As per RFC2460 section 4.4, if routing type is unrecognized:
|
|
* if segments left = 0, ignore the header
|
|
* if segments left > 0, discard packet and send icmp error pointing
|
|
* to the routing type
|
|
*/
|
|
|
|
PRINTF("Processing Routing header\n");
|
|
if(UIP_ROUTING_BUF->seg_left > 0) {
|
|
uip_icmp6_error_output(ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER, UIP_IPH_LEN + uip_ext_len + 2);
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
UIP_LOG("ip6: unrecognized routing type");
|
|
goto send;
|
|
}
|
|
uip_next_hdr = &UIP_EXT_BUF->next;
|
|
uip_ext_len += (UIP_EXT_BUF->len << 3) + 8;
|
|
break;
|
|
case UIP_PROTO_FRAG:
|
|
/* Fragmentation header:call the reassembly function, then leave */
|
|
#if UIP_CONF_IPV6_REASSEMBLY
|
|
PRINTF("Processing frag header\n");
|
|
uip_len = uip_reass();
|
|
if(uip_len == 0) {
|
|
goto drop;
|
|
}
|
|
if(uip_reassflags & UIP_REASS_FLAG_ERROR_MSG){
|
|
/* we are not done with reassembly, this is an error message */
|
|
goto send;
|
|
}
|
|
/*packet is reassembled, reset the next hdr to the beginning
|
|
of the IP header and restart the parsing of the reassembled pkt*/
|
|
PRINTF("Processing reassembled packet\n");
|
|
uip_ext_len = 0;
|
|
uip_ext_bitmap = 0;
|
|
uip_next_hdr = &UIP_IP_BUF->proto;
|
|
break;
|
|
#else /* UIP_CONF_IPV6_REASSEMBLY */
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
UIP_STAT(++uip_stat.ip.fragerr);
|
|
UIP_LOG("ip: fragment dropped.");
|
|
goto drop;
|
|
#endif /* UIP_CONF_IPV6_REASSEMBLY */
|
|
case UIP_PROTO_NONE:
|
|
goto drop;
|
|
default:
|
|
goto bad_hdr;
|
|
}
|
|
}
|
|
bad_hdr:
|
|
/*
|
|
* RFC 2460 send error message parameterr problem, code unrecognized
|
|
* next header, pointing to the next header field
|
|
*/
|
|
uip_icmp6_error_output(ICMP6_PARAM_PROB, ICMP6_PARAMPROB_NEXTHEADER, (u32_t)(uip_next_hdr - (uint8_t *)UIP_IP_BUF));
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
UIP_STAT(++uip_stat.ip.protoerr);
|
|
UIP_LOG("ip6: unrecognized header");
|
|
goto send;
|
|
/* End of headers processing */
|
|
|
|
icmp6_input:
|
|
/* This is IPv6 ICMPv6 processing code. */
|
|
PRINTF("icmp6_input: length %d\n", uip_len);
|
|
|
|
#if UIP_CONF_IPV6_CHECKS
|
|
/* Compute and check the ICMP header checksum */
|
|
if(uip_icmp6chksum() != 0xffff) {
|
|
UIP_STAT(++uip_stat.icmp.drop);
|
|
UIP_STAT(++uip_stat.icmp.chkerr);
|
|
UIP_LOG("icmpv6: bad checksum.");
|
|
goto drop;
|
|
}
|
|
#endif /*UIP_CONF_IPV6_CHECKS*/
|
|
|
|
UIP_STAT(++uip_stat.icmp.recv);
|
|
/*
|
|
* Here we process incoming ICMPv6 packets
|
|
* For echo request, we send echo reply
|
|
* For ND pkts, we call the appropriate function in uip-nd6.c
|
|
* We do not treat Error messages for now
|
|
* If no pkt is to be sent as an answer to the incoming one, we
|
|
* "goto drop". Else we just break; then at the after the "switch"
|
|
* we "goto send"
|
|
*/
|
|
#if UIP_CONF_ICMP6
|
|
UIP_ICMP6_APPCALL(UIP_ICMP_BUF->type);
|
|
#endif /*UIP_CONF_ICMP6*/
|
|
|
|
switch(UIP_ICMP_BUF->type) {
|
|
case ICMP6_NS:
|
|
uip_nd6_ns_input();
|
|
break;
|
|
case ICMP6_NA:
|
|
uip_nd6_na_input();
|
|
break;
|
|
case ICMP6_RS:
|
|
#if UIP_CONF_ROUTER && UIP_ND6_SEND_RA
|
|
uip_nd6_rs_input();
|
|
#else /* UIP_CONF_ROUTER && UIP_ND6_SEND_RA */
|
|
UIP_STAT(++uip_stat.icmp.drop);
|
|
uip_len = 0;
|
|
#endif /* UIP_CONF_ROUTER && UIP_ND6_SEND_RA */
|
|
break;
|
|
case ICMP6_RA:
|
|
#if UIP_CONF_ROUTER
|
|
UIP_STAT(++uip_stat.icmp.drop);
|
|
uip_len = 0;
|
|
#else /* UIP_CONF_ROUTER */
|
|
uip_nd6_ra_input();
|
|
#endif /* UIP_CONF_ROUTER */
|
|
break;
|
|
#if UIP_CONF_IPV6_RPL
|
|
case ICMP6_RPL:
|
|
uip_rpl_input();
|
|
break;
|
|
#endif /* UIP_CONF_IPV6_RPL */
|
|
case ICMP6_ECHO_REQUEST:
|
|
uip_icmp6_echo_request_input();
|
|
break;
|
|
case ICMP6_ECHO_REPLY:
|
|
/** \note We don't implement any application callback for now */
|
|
PRINTF("Received an icmp6 echo reply\n");
|
|
UIP_STAT(++uip_stat.icmp.recv);
|
|
uip_len = 0;
|
|
break;
|
|
default:
|
|
PRINTF("Unknown icmp6 message type %d\n", UIP_ICMP_BUF->type);
|
|
UIP_STAT(++uip_stat.icmp.drop);
|
|
UIP_STAT(++uip_stat.icmp.typeerr);
|
|
UIP_LOG("icmp6: unknown ICMP message.");
|
|
uip_len = 0;
|
|
break;
|
|
}
|
|
|
|
if(uip_len > 0) {
|
|
goto send;
|
|
} else {
|
|
goto drop;
|
|
}
|
|
/* End of IPv6 ICMP processing. */
|
|
|
|
|
|
#if UIP_UDP
|
|
/* UDP input processing. */
|
|
udp_input:
|
|
PRINTF("Receiving UDP packet\n");
|
|
UIP_STAT(++uip_stat.udp.recv);
|
|
|
|
/* UDP processing is really just a hack. We don't do anything to the
|
|
UDP/IP headers, but let the UDP application do all the hard
|
|
work. If the application sets uip_slen, it has a packet to
|
|
send. */
|
|
#if UIP_UDP_CHECKSUMS
|
|
uip_len = uip_len - uip_l3_udp_hdr_len;
|
|
uip_appdata = &uip_buf[uip_l2_l3_udp_hdr_len];
|
|
if(UIP_UDP_BUF->udpchksum != 0 && uip_udpchksum() != 0xffff) {
|
|
UIP_STAT(++uip_stat.udp.drop);
|
|
UIP_STAT(++uip_stat.udp.chkerr);
|
|
PRINTF("udp: bad checksum 0x%04x 0x%04x\n", UIP_UDP_BUF->udpchksum,
|
|
uip_udpchksum());
|
|
goto drop;
|
|
}
|
|
#else /* UIP_UDP_CHECKSUMS */
|
|
uip_len = uip_len - uip_l3_udp_hdr_len;
|
|
#endif /* UIP_UDP_CHECKSUMS */
|
|
|
|
/* Make sure that the UDP destination port number is not zero. */
|
|
if(UIP_UDP_BUF->destport == 0) {
|
|
PRINTF("udp: zero port.\n");
|
|
goto drop;
|
|
}
|
|
|
|
/* Demultiplex this UDP packet between the UDP "connections". */
|
|
for(uip_udp_conn = &uip_udp_conns[0];
|
|
uip_udp_conn < &uip_udp_conns[UIP_UDP_CONNS];
|
|
++uip_udp_conn) {
|
|
/* If the local UDP port is non-zero, the connection is considered
|
|
to be used. If so, the local port number is checked against the
|
|
destination port number in the received packet. If the two port
|
|
numbers match, the remote port number is checked if the
|
|
connection is bound to a remote port. Finally, if the
|
|
connection is bound to a remote IP address, the source IP
|
|
address of the packet is checked. */
|
|
if(uip_udp_conn->lport != 0 &&
|
|
UIP_UDP_BUF->destport == uip_udp_conn->lport &&
|
|
(uip_udp_conn->rport == 0 ||
|
|
UIP_UDP_BUF->srcport == uip_udp_conn->rport) &&
|
|
(uip_is_addr_unspecified(&uip_udp_conn->ripaddr) ||
|
|
uip_ipaddr_cmp(&UIP_IP_BUF->srcipaddr, &uip_udp_conn->ripaddr))) {
|
|
goto udp_found;
|
|
}
|
|
}
|
|
PRINTF("udp: no matching connection found\n");
|
|
|
|
#if UIP_UDP_SEND_UNREACH_NOPORT
|
|
uip_icmp6_error_output(ICMP6_DST_UNREACH, ICMP6_DST_UNREACH_NOPORT, 0);
|
|
UIP_STAT(++uip_stat.ip.drop);
|
|
goto send;
|
|
#else
|
|
goto drop;
|
|
#endif
|
|
|
|
udp_found:
|
|
PRINTF("In udp_found\n");
|
|
|
|
uip_conn = NULL;
|
|
uip_flags = UIP_NEWDATA;
|
|
uip_sappdata = uip_appdata = &uip_buf[uip_l2_l3_udp_hdr_len];
|
|
uip_slen = 0;
|
|
UIP_UDP_APPCALL();
|
|
|
|
udp_send:
|
|
PRINTF("In udp_send\n");
|
|
|
|
if(uip_slen == 0) {
|
|
goto drop;
|
|
}
|
|
/* TODO: ext_header len here ? */
|
|
uip_len = uip_slen + uip_l3_udp_hdr_len; /* UIP_IPUDPH_LEN; */
|
|
|
|
/* For IPv6, the IP length field does not include the IPv6 IP header
|
|
length. */
|
|
UIP_IP_BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8);
|
|
UIP_IP_BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff);
|
|
|
|
UIP_IP_BUF->ttl = uip_udp_conn->ttl;
|
|
UIP_IP_BUF->proto = UIP_PROTO_UDP;
|
|
|
|
UIP_UDP_BUF->udplen = UIP_HTONS(uip_slen + UIP_UDPH_LEN);
|
|
UIP_UDP_BUF->udpchksum = 0;
|
|
|
|
UIP_UDP_BUF->srcport = uip_udp_conn->lport;
|
|
UIP_UDP_BUF->destport = uip_udp_conn->rport;
|
|
|
|
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &uip_udp_conn->ripaddr);
|
|
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
|
|
|
|
uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPTCPH_LEN];
|
|
|
|
#if UIP_UDP_CHECKSUMS
|
|
/* Calculate UDP checksum. */
|
|
UIP_UDP_BUF->udpchksum = ~(uip_udpchksum());
|
|
if(UIP_UDP_BUF->udpchksum == 0) {
|
|
UIP_UDP_BUF->udpchksum = 0xffff;
|
|
}
|
|
#endif /* UIP_UDP_CHECKSUMS */
|
|
UIP_STAT(++uip_stat.udp.sent);
|
|
goto ip_send_nolen;
|
|
#endif /* UIP_UDP */
|
|
|
|
#if UIP_TCP
|
|
/* TCP input processing. */
|
|
tcp_input:
|
|
|
|
remove_ext_hdr();
|
|
|
|
UIP_STAT(++uip_stat.tcp.recv);
|
|
PRINTF("Receiving TCP packet\n");
|
|
/* Start of TCP input header processing code. */
|
|
|
|
if(uip_tcpchksum() != 0xffff) { /* Compute and check the TCP
|
|
checksum. */
|
|
UIP_STAT(++uip_stat.tcp.drop);
|
|
UIP_STAT(++uip_stat.tcp.chkerr);
|
|
PRINTF("tcp: bad checksum 0x%04x 0x%04x\n", UIP_TCP_BUF->tcpchksum,
|
|
uip_tcpchksum());
|
|
goto drop;
|
|
}
|
|
|
|
/* Make sure that the TCP port number is not zero. */
|
|
if(UIP_TCP_BUF->destport == 0 || UIP_TCP_BUF->srcport == 0) {
|
|
PRINTF("tcp: zero port.");
|
|
goto drop;
|
|
}
|
|
|
|
/* Demultiplex this segment. */
|
|
/* First check any active connections. */
|
|
for(uip_connr = &uip_conns[0]; uip_connr <= &uip_conns[UIP_CONNS - 1];
|
|
++uip_connr) {
|
|
if(uip_connr->tcpstateflags != UIP_CLOSED &&
|
|
UIP_TCP_BUF->destport == uip_connr->lport &&
|
|
UIP_TCP_BUF->srcport == uip_connr->rport &&
|
|
uip_ipaddr_cmp(&UIP_IP_BUF->srcipaddr, &uip_connr->ripaddr)) {
|
|
goto found;
|
|
}
|
|
}
|
|
|
|
/* If we didn't find and active connection that expected the packet,
|
|
either this packet is an old duplicate, or this is a SYN packet
|
|
destined for a connection in LISTEN. If the SYN flag isn't set,
|
|
it is an old packet and we send a RST. */
|
|
if((UIP_TCP_BUF->flags & TCP_CTL) != TCP_SYN) {
|
|
goto reset;
|
|
}
|
|
|
|
tmp16 = UIP_TCP_BUF->destport;
|
|
/* Next, check listening connections. */
|
|
for(c = 0; c < UIP_LISTENPORTS; ++c) {
|
|
if(tmp16 == uip_listenports[c]) {
|
|
goto found_listen;
|
|
}
|
|
}
|
|
|
|
/* No matching connection found, so we send a RST packet. */
|
|
UIP_STAT(++uip_stat.tcp.synrst);
|
|
|
|
reset:
|
|
PRINTF("In reset\n");
|
|
/* We do not send resets in response to resets. */
|
|
if(UIP_TCP_BUF->flags & TCP_RST) {
|
|
goto drop;
|
|
}
|
|
|
|
UIP_STAT(++uip_stat.tcp.rst);
|
|
|
|
UIP_TCP_BUF->flags = TCP_RST | TCP_ACK;
|
|
uip_len = UIP_IPTCPH_LEN;
|
|
UIP_TCP_BUF->tcpoffset = 5 << 4;
|
|
|
|
/* Flip the seqno and ackno fields in the TCP header. */
|
|
c = UIP_TCP_BUF->seqno[3];
|
|
UIP_TCP_BUF->seqno[3] = UIP_TCP_BUF->ackno[3];
|
|
UIP_TCP_BUF->ackno[3] = c;
|
|
|
|
c = UIP_TCP_BUF->seqno[2];
|
|
UIP_TCP_BUF->seqno[2] = UIP_TCP_BUF->ackno[2];
|
|
UIP_TCP_BUF->ackno[2] = c;
|
|
|
|
c = UIP_TCP_BUF->seqno[1];
|
|
UIP_TCP_BUF->seqno[1] = UIP_TCP_BUF->ackno[1];
|
|
UIP_TCP_BUF->ackno[1] = c;
|
|
|
|
c = UIP_TCP_BUF->seqno[0];
|
|
UIP_TCP_BUF->seqno[0] = UIP_TCP_BUF->ackno[0];
|
|
UIP_TCP_BUF->ackno[0] = c;
|
|
|
|
/* We also have to increase the sequence number we are
|
|
acknowledging. If the least significant byte overflowed, we need
|
|
to propagate the carry to the other bytes as well. */
|
|
if(++UIP_TCP_BUF->ackno[3] == 0) {
|
|
if(++UIP_TCP_BUF->ackno[2] == 0) {
|
|
if(++UIP_TCP_BUF->ackno[1] == 0) {
|
|
++UIP_TCP_BUF->ackno[0];
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Swap port numbers. */
|
|
tmp16 = UIP_TCP_BUF->srcport;
|
|
UIP_TCP_BUF->srcport = UIP_TCP_BUF->destport;
|
|
UIP_TCP_BUF->destport = tmp16;
|
|
|
|
/* Swap IP addresses. */
|
|
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &UIP_IP_BUF->srcipaddr);
|
|
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr, &UIP_IP_BUF->destipaddr);
|
|
/* And send out the RST packet! */
|
|
goto tcp_send_noconn;
|
|
|
|
/* This label will be jumped to if we matched the incoming packet
|
|
with a connection in LISTEN. In that case, we should create a new
|
|
connection and send a SYNACK in return. */
|
|
found_listen:
|
|
PRINTF("In found listen\n");
|
|
/* First we check if there are any connections avaliable. Unused
|
|
connections are kept in the same table as used connections, but
|
|
unused ones have the tcpstate set to CLOSED. Also, connections in
|
|
TIME_WAIT are kept track of and we'll use the oldest one if no
|
|
CLOSED connections are found. Thanks to Eddie C. Dost for a very
|
|
nice algorithm for the TIME_WAIT search. */
|
|
uip_connr = 0;
|
|
for(c = 0; c < UIP_CONNS; ++c) {
|
|
if(uip_conns[c].tcpstateflags == UIP_CLOSED) {
|
|
uip_connr = &uip_conns[c];
|
|
break;
|
|
}
|
|
if(uip_conns[c].tcpstateflags == UIP_TIME_WAIT) {
|
|
if(uip_connr == 0 ||
|
|
uip_conns[c].timer > uip_connr->timer) {
|
|
uip_connr = &uip_conns[c];
|
|
}
|
|
}
|
|
}
|
|
|
|
if(uip_connr == 0) {
|
|
/* All connections are used already, we drop packet and hope that
|
|
the remote end will retransmit the packet at a time when we
|
|
have more spare connections. */
|
|
UIP_STAT(++uip_stat.tcp.syndrop);
|
|
UIP_LOG("tcp: found no unused connections.");
|
|
goto drop;
|
|
}
|
|
uip_conn = uip_connr;
|
|
|
|
/* Fill in the necessary fields for the new connection. */
|
|
uip_connr->rto = uip_connr->timer = UIP_RTO;
|
|
uip_connr->sa = 0;
|
|
uip_connr->sv = 4;
|
|
uip_connr->nrtx = 0;
|
|
uip_connr->lport = UIP_TCP_BUF->destport;
|
|
uip_connr->rport = UIP_TCP_BUF->srcport;
|
|
uip_ipaddr_copy(&uip_connr->ripaddr, &UIP_IP_BUF->srcipaddr);
|
|
uip_connr->tcpstateflags = UIP_SYN_RCVD;
|
|
|
|
uip_connr->snd_nxt[0] = iss[0];
|
|
uip_connr->snd_nxt[1] = iss[1];
|
|
uip_connr->snd_nxt[2] = iss[2];
|
|
uip_connr->snd_nxt[3] = iss[3];
|
|
uip_connr->len = 1;
|
|
|
|
/* rcv_nxt should be the seqno from the incoming packet + 1. */
|
|
uip_connr->rcv_nxt[3] = UIP_TCP_BUF->seqno[3];
|
|
uip_connr->rcv_nxt[2] = UIP_TCP_BUF->seqno[2];
|
|
uip_connr->rcv_nxt[1] = UIP_TCP_BUF->seqno[1];
|
|
uip_connr->rcv_nxt[0] = UIP_TCP_BUF->seqno[0];
|
|
uip_add_rcv_nxt(1);
|
|
|
|
/* Parse the TCP MSS option, if present. */
|
|
if((UIP_TCP_BUF->tcpoffset & 0xf0) > 0x50) {
|
|
for(c = 0; c < ((UIP_TCP_BUF->tcpoffset >> 4) - 5) << 2 ;) {
|
|
opt = uip_buf[UIP_TCPIP_HLEN + uip_ext_len + UIP_LLH_LEN + c];
|
|
if(opt == TCP_OPT_END) {
|
|
/* End of options. */
|
|
break;
|
|
} else if(opt == TCP_OPT_NOOP) {
|
|
++c;
|
|
/* NOP option. */
|
|
} else if(opt == TCP_OPT_MSS &&
|
|
uip_buf[UIP_TCPIP_HLEN + uip_ext_len + UIP_LLH_LEN + 1 + c] == TCP_OPT_MSS_LEN) {
|
|
/* An MSS option with the right option length. */
|
|
tmp16 = ((u16_t)uip_buf[UIP_TCPIP_HLEN + uip_ext_len + UIP_LLH_LEN + 2 + c] << 8) |
|
|
(u16_t)uip_buf[UIP_IPTCPH_LEN + uip_ext_len + UIP_LLH_LEN + 3 + c];
|
|
uip_connr->initialmss = uip_connr->mss =
|
|
tmp16 > UIP_TCP_MSS? UIP_TCP_MSS: tmp16;
|
|
|
|
/* And we are done processing options. */
|
|
break;
|
|
} else {
|
|
/* All other options have a length field, so that we easily
|
|
can skip past them. */
|
|
if(uip_buf[UIP_TCPIP_HLEN + uip_ext_len + UIP_LLH_LEN + 1 + c] == 0) {
|
|
/* If the length field is zero, the options are malformed
|
|
and we don't process them further. */
|
|
break;
|
|
}
|
|
c += uip_buf[UIP_TCPIP_HLEN + uip_ext_len + UIP_LLH_LEN + 1 + c];
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Our response will be a SYNACK. */
|
|
#if UIP_ACTIVE_OPEN
|
|
tcp_send_synack:
|
|
UIP_TCP_BUF->flags = TCP_ACK;
|
|
|
|
tcp_send_syn:
|
|
UIP_TCP_BUF->flags |= TCP_SYN;
|
|
#else /* UIP_ACTIVE_OPEN */
|
|
tcp_send_synack:
|
|
UIP_TCP_BUF->flags = TCP_SYN | TCP_ACK;
|
|
#endif /* UIP_ACTIVE_OPEN */
|
|
|
|
/* We send out the TCP Maximum Segment Size option with our
|
|
SYNACK. */
|
|
UIP_TCP_BUF->optdata[0] = TCP_OPT_MSS;
|
|
UIP_TCP_BUF->optdata[1] = TCP_OPT_MSS_LEN;
|
|
UIP_TCP_BUF->optdata[2] = (UIP_TCP_MSS) / 256;
|
|
UIP_TCP_BUF->optdata[3] = (UIP_TCP_MSS) & 255;
|
|
uip_len = UIP_IPTCPH_LEN + TCP_OPT_MSS_LEN + uip_ext_len;
|
|
UIP_TCP_BUF->tcpoffset = ((UIP_TCPH_LEN + TCP_OPT_MSS_LEN) / 4) << 4;
|
|
goto tcp_send;
|
|
|
|
/* This label will be jumped to if we found an active connection. */
|
|
found:
|
|
PRINTF("In found\n");
|
|
uip_conn = uip_connr;
|
|
uip_flags = 0;
|
|
/* We do a very naive form of TCP reset processing; we just accept
|
|
any RST and kill our connection. We should in fact check if the
|
|
sequence number of this reset is wihtin our advertised window
|
|
before we accept the reset. */
|
|
if(UIP_TCP_BUF->flags & TCP_RST) {
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
|
UIP_LOG("tcp: got reset, aborting connection.");
|
|
uip_flags = UIP_ABORT;
|
|
UIP_APPCALL();
|
|
goto drop;
|
|
}
|
|
/* Calculate the length of the data, if the application has sent
|
|
any data to us. */
|
|
c = (UIP_TCP_BUF->tcpoffset >> 4) << 2;
|
|
/* uip_len will contain the length of the actual TCP data. This is
|
|
calculated by subtracing the length of the TCP header (in
|
|
c) and the length of the IP header (20 bytes). */
|
|
uip_len = uip_len - c - UIP_IPH_LEN - uip_ext_len;
|
|
|
|
/* First, check if the sequence number of the incoming packet is
|
|
what we're expecting next. If not, we send out an ACK with the
|
|
correct numbers in, unless we are in the SYN_RCVD state and
|
|
receive a SYN, in which case we should retransmit our SYNACK
|
|
(which is done futher down). */
|
|
if(!((((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) &&
|
|
((UIP_TCP_BUF->flags & TCP_CTL) == (TCP_SYN | TCP_ACK))) ||
|
|
(((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_RCVD) &&
|
|
((UIP_TCP_BUF->flags & TCP_CTL) == TCP_SYN)))) {
|
|
if((uip_len > 0 || ((UIP_TCP_BUF->flags & (TCP_SYN | TCP_FIN)) != 0)) &&
|
|
(UIP_TCP_BUF->seqno[0] != uip_connr->rcv_nxt[0] ||
|
|
UIP_TCP_BUF->seqno[1] != uip_connr->rcv_nxt[1] ||
|
|
UIP_TCP_BUF->seqno[2] != uip_connr->rcv_nxt[2] ||
|
|
UIP_TCP_BUF->seqno[3] != uip_connr->rcv_nxt[3])) {
|
|
|
|
if(UIP_TCP_BUF->flags & TCP_SYN) {
|
|
goto tcp_send_synack;
|
|
}
|
|
goto tcp_send_ack;
|
|
}
|
|
}
|
|
|
|
/* Next, check if the incoming segment acknowledges any outstanding
|
|
data. If so, we update the sequence number, reset the length of
|
|
the outstanding data, calculate RTT estimations, and reset the
|
|
retransmission timer. */
|
|
if((UIP_TCP_BUF->flags & TCP_ACK) && uip_outstanding(uip_connr)) {
|
|
uip_add32(uip_connr->snd_nxt, uip_connr->len);
|
|
|
|
if(UIP_TCP_BUF->ackno[0] == uip_acc32[0] &&
|
|
UIP_TCP_BUF->ackno[1] == uip_acc32[1] &&
|
|
UIP_TCP_BUF->ackno[2] == uip_acc32[2] &&
|
|
UIP_TCP_BUF->ackno[3] == uip_acc32[3]) {
|
|
/* Update sequence number. */
|
|
uip_connr->snd_nxt[0] = uip_acc32[0];
|
|
uip_connr->snd_nxt[1] = uip_acc32[1];
|
|
uip_connr->snd_nxt[2] = uip_acc32[2];
|
|
uip_connr->snd_nxt[3] = uip_acc32[3];
|
|
|
|
/* Do RTT estimation, unless we have done retransmissions. */
|
|
if(uip_connr->nrtx == 0) {
|
|
signed char m;
|
|
m = uip_connr->rto - uip_connr->timer;
|
|
/* This is taken directly from VJs original code in his paper */
|
|
m = m - (uip_connr->sa >> 3);
|
|
uip_connr->sa += m;
|
|
if(m < 0) {
|
|
m = -m;
|
|
}
|
|
m = m - (uip_connr->sv >> 2);
|
|
uip_connr->sv += m;
|
|
uip_connr->rto = (uip_connr->sa >> 3) + uip_connr->sv;
|
|
|
|
}
|
|
/* Set the acknowledged flag. */
|
|
uip_flags = UIP_ACKDATA;
|
|
/* Reset the retransmission timer. */
|
|
uip_connr->timer = uip_connr->rto;
|
|
|
|
/* Reset length of outstanding data. */
|
|
uip_connr->len = 0;
|
|
}
|
|
|
|
}
|
|
|
|
/* Do different things depending on in what state the connection is. */
|
|
switch(uip_connr->tcpstateflags & UIP_TS_MASK) {
|
|
/* CLOSED and LISTEN are not handled here. CLOSE_WAIT is not
|
|
implemented, since we force the application to close when the
|
|
peer sends a FIN (hence the application goes directly from
|
|
ESTABLISHED to LAST_ACK). */
|
|
case UIP_SYN_RCVD:
|
|
/* In SYN_RCVD we have sent out a SYNACK in response to a SYN, and
|
|
we are waiting for an ACK that acknowledges the data we sent
|
|
out the last time. Therefore, we want to have the UIP_ACKDATA
|
|
flag set. If so, we enter the ESTABLISHED state. */
|
|
if(uip_flags & UIP_ACKDATA) {
|
|
uip_connr->tcpstateflags = UIP_ESTABLISHED;
|
|
uip_flags = UIP_CONNECTED;
|
|
uip_connr->len = 0;
|
|
if(uip_len > 0) {
|
|
uip_flags |= UIP_NEWDATA;
|
|
uip_add_rcv_nxt(uip_len);
|
|
}
|
|
uip_slen = 0;
|
|
UIP_APPCALL();
|
|
goto appsend;
|
|
}
|
|
/* We need to retransmit the SYNACK */
|
|
if((UIP_TCP_BUF->flags & TCP_CTL) == TCP_SYN) {
|
|
goto tcp_send_synack;
|
|
}
|
|
goto drop;
|
|
#if UIP_ACTIVE_OPEN
|
|
case UIP_SYN_SENT:
|
|
/* In SYN_SENT, we wait for a SYNACK that is sent in response to
|
|
our SYN. The rcv_nxt is set to sequence number in the SYNACK
|
|
plus one, and we send an ACK. We move into the ESTABLISHED
|
|
state. */
|
|
if((uip_flags & UIP_ACKDATA) &&
|
|
(UIP_TCP_BUF->flags & TCP_CTL) == (TCP_SYN | TCP_ACK)) {
|
|
|
|
/* Parse the TCP MSS option, if present. */
|
|
if((UIP_TCP_BUF->tcpoffset & 0xf0) > 0x50) {
|
|
for(c = 0; c < ((UIP_TCP_BUF->tcpoffset >> 4) - 5) << 2 ;) {
|
|
opt = uip_buf[UIP_IPTCPH_LEN + UIP_LLH_LEN + c + uip_ext_len];
|
|
if(opt == TCP_OPT_END) {
|
|
/* End of options. */
|
|
break;
|
|
} else if(opt == TCP_OPT_NOOP) {
|
|
++c;
|
|
/* NOP option. */
|
|
} else if(opt == TCP_OPT_MSS &&
|
|
uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c + uip_ext_len] == TCP_OPT_MSS_LEN) {
|
|
/* An MSS option with the right option length. */
|
|
tmp16 = (uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 2 + c + uip_ext_len] << 8) |
|
|
uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 3 + c + uip_ext_len];
|
|
uip_connr->initialmss =
|
|
uip_connr->mss = tmp16 > UIP_TCP_MSS? UIP_TCP_MSS: tmp16;
|
|
|
|
/* And we are done processing options. */
|
|
break;
|
|
} else {
|
|
/* All other options have a length field, so that we easily
|
|
can skip past them. */
|
|
if(uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c + uip_ext_len] == 0) {
|
|
/* If the length field is zero, the options are malformed
|
|
and we don't process them further. */
|
|
break;
|
|
}
|
|
c += uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c + uip_ext_len];
|
|
}
|
|
}
|
|
}
|
|
uip_connr->tcpstateflags = UIP_ESTABLISHED;
|
|
uip_connr->rcv_nxt[0] = UIP_TCP_BUF->seqno[0];
|
|
uip_connr->rcv_nxt[1] = UIP_TCP_BUF->seqno[1];
|
|
uip_connr->rcv_nxt[2] = UIP_TCP_BUF->seqno[2];
|
|
uip_connr->rcv_nxt[3] = UIP_TCP_BUF->seqno[3];
|
|
uip_add_rcv_nxt(1);
|
|
uip_flags = UIP_CONNECTED | UIP_NEWDATA;
|
|
uip_connr->len = 0;
|
|
uip_len = 0;
|
|
uip_slen = 0;
|
|
UIP_APPCALL();
|
|
goto appsend;
|
|
}
|
|
/* Inform the application that the connection failed */
|
|
uip_flags = UIP_ABORT;
|
|
UIP_APPCALL();
|
|
/* The connection is closed after we send the RST */
|
|
uip_conn->tcpstateflags = UIP_CLOSED;
|
|
goto reset;
|
|
#endif /* UIP_ACTIVE_OPEN */
|
|
|
|
case UIP_ESTABLISHED:
|
|
/* In the ESTABLISHED state, we call upon the application to feed
|
|
data into the uip_buf. If the UIP_ACKDATA flag is set, the
|
|
application should put new data into the buffer, otherwise we are
|
|
retransmitting an old segment, and the application should put that
|
|
data into the buffer.
|
|
|
|
If the incoming packet is a FIN, we should close the connection on
|
|
this side as well, and we send out a FIN and enter the LAST_ACK
|
|
state. We require that there is no outstanding data; otherwise the
|
|
sequence numbers will be screwed up. */
|
|
|
|
if(UIP_TCP_BUF->flags & TCP_FIN && !(uip_connr->tcpstateflags & UIP_STOPPED)) {
|
|
if(uip_outstanding(uip_connr)) {
|
|
goto drop;
|
|
}
|
|
uip_add_rcv_nxt(1 + uip_len);
|
|
uip_flags |= UIP_CLOSE;
|
|
if(uip_len > 0) {
|
|
uip_flags |= UIP_NEWDATA;
|
|
}
|
|
UIP_APPCALL();
|
|
uip_connr->len = 1;
|
|
uip_connr->tcpstateflags = UIP_LAST_ACK;
|
|
uip_connr->nrtx = 0;
|
|
tcp_send_finack:
|
|
UIP_TCP_BUF->flags = TCP_FIN | TCP_ACK;
|
|
goto tcp_send_nodata;
|
|
}
|
|
|
|
/* Check the URG flag. If this is set, the segment carries urgent
|
|
data that we must pass to the application. */
|
|
if((UIP_TCP_BUF->flags & TCP_URG) != 0) {
|
|
#if UIP_URGDATA > 0
|
|
uip_urglen = (UIP_TCP_BUF->urgp[0] << 8) | UIP_TCP_BUF->urgp[1];
|
|
if(uip_urglen > uip_len) {
|
|
/* There is more urgent data in the next segment to come. */
|
|
uip_urglen = uip_len;
|
|
}
|
|
uip_add_rcv_nxt(uip_urglen);
|
|
uip_len -= uip_urglen;
|
|
uip_urgdata = uip_appdata;
|
|
uip_appdata += uip_urglen;
|
|
} else {
|
|
uip_urglen = 0;
|
|
#else /* UIP_URGDATA > 0 */
|
|
uip_appdata = ((char *)uip_appdata) + ((UIP_TCP_BUF->urgp[0] << 8) | UIP_TCP_BUF->urgp[1]);
|
|
uip_len -= (UIP_TCP_BUF->urgp[0] << 8) | UIP_TCP_BUF->urgp[1];
|
|
#endif /* UIP_URGDATA > 0 */
|
|
}
|
|
|
|
/* If uip_len > 0 we have TCP data in the packet, and we flag this
|
|
by setting the UIP_NEWDATA flag and update the sequence number
|
|
we acknowledge. If the application has stopped the dataflow
|
|
using uip_stop(), we must not accept any data packets from the
|
|
remote host. */
|
|
if(uip_len > 0 && !(uip_connr->tcpstateflags & UIP_STOPPED)) {
|
|
uip_flags |= UIP_NEWDATA;
|
|
uip_add_rcv_nxt(uip_len);
|
|
}
|
|
|
|
/* Check if the available buffer space advertised by the other end
|
|
is smaller than the initial MSS for this connection. If so, we
|
|
set the current MSS to the window size to ensure that the
|
|
application does not send more data than the other end can
|
|
handle.
|
|
|
|
If the remote host advertises a zero window, we set the MSS to
|
|
the initial MSS so that the application will send an entire MSS
|
|
of data. This data will not be acknowledged by the receiver,
|
|
and the application will retransmit it. This is called the
|
|
"persistent timer" and uses the retransmission mechanim.
|
|
*/
|
|
tmp16 = ((u16_t)UIP_TCP_BUF->wnd[0] << 8) + (u16_t)UIP_TCP_BUF->wnd[1];
|
|
if(tmp16 > uip_connr->initialmss ||
|
|
tmp16 == 0) {
|
|
tmp16 = uip_connr->initialmss;
|
|
}
|
|
uip_connr->mss = tmp16;
|
|
|
|
/* If this packet constitutes an ACK for outstanding data (flagged
|
|
by the UIP_ACKDATA flag, we should call the application since it
|
|
might want to send more data. If the incoming packet had data
|
|
from the peer (as flagged by the UIP_NEWDATA flag), the
|
|
application must also be notified.
|
|
|
|
When the application is called, the global variable uip_len
|
|
contains the length of the incoming data. The application can
|
|
access the incoming data through the global pointer
|
|
uip_appdata, which usually points UIP_IPTCPH_LEN + UIP_LLH_LEN
|
|
bytes into the uip_buf array.
|
|
|
|
If the application wishes to send any data, this data should be
|
|
put into the uip_appdata and the length of the data should be
|
|
put into uip_len. If the application don't have any data to
|
|
send, uip_len must be set to 0. */
|
|
if(uip_flags & (UIP_NEWDATA | UIP_ACKDATA)) {
|
|
uip_slen = 0;
|
|
UIP_APPCALL();
|
|
|
|
appsend:
|
|
|
|
if(uip_flags & UIP_ABORT) {
|
|
uip_slen = 0;
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
|
UIP_TCP_BUF->flags = TCP_RST | TCP_ACK;
|
|
goto tcp_send_nodata;
|
|
}
|
|
|
|
if(uip_flags & UIP_CLOSE) {
|
|
uip_slen = 0;
|
|
uip_connr->len = 1;
|
|
uip_connr->tcpstateflags = UIP_FIN_WAIT_1;
|
|
uip_connr->nrtx = 0;
|
|
UIP_TCP_BUF->flags = TCP_FIN | TCP_ACK;
|
|
goto tcp_send_nodata;
|
|
}
|
|
|
|
/* If uip_slen > 0, the application has data to be sent. */
|
|
if(uip_slen > 0) {
|
|
|
|
/* If the connection has acknowledged data, the contents of
|
|
the ->len variable should be discarded. */
|
|
if((uip_flags & UIP_ACKDATA) != 0) {
|
|
uip_connr->len = 0;
|
|
}
|
|
|
|
/* If the ->len variable is non-zero the connection has
|
|
already data in transit and cannot send anymore right
|
|
now. */
|
|
if(uip_connr->len == 0) {
|
|
|
|
/* The application cannot send more than what is allowed by
|
|
the mss (the minumum of the MSS and the available
|
|
window). */
|
|
if(uip_slen > uip_connr->mss) {
|
|
uip_slen = uip_connr->mss;
|
|
}
|
|
|
|
/* Remember how much data we send out now so that we know
|
|
when everything has been acknowledged. */
|
|
uip_connr->len = uip_slen;
|
|
} else {
|
|
|
|
/* If the application already had unacknowledged data, we
|
|
make sure that the application does not send (i.e.,
|
|
retransmit) out more than it previously sent out. */
|
|
uip_slen = uip_connr->len;
|
|
}
|
|
}
|
|
uip_connr->nrtx = 0;
|
|
apprexmit:
|
|
uip_appdata = uip_sappdata;
|
|
|
|
/* If the application has data to be sent, or if the incoming
|
|
packet had new data in it, we must send out a packet. */
|
|
if(uip_slen > 0 && uip_connr->len > 0) {
|
|
/* Add the length of the IP and TCP headers. */
|
|
uip_len = uip_connr->len + UIP_TCPIP_HLEN;
|
|
/* We always set the ACK flag in response packets. */
|
|
UIP_TCP_BUF->flags = TCP_ACK | TCP_PSH;
|
|
/* Send the packet. */
|
|
goto tcp_send_noopts;
|
|
}
|
|
/* If there is no data to send, just send out a pure ACK if
|
|
there is newdata. */
|
|
if(uip_flags & UIP_NEWDATA) {
|
|
uip_len = UIP_TCPIP_HLEN;
|
|
UIP_TCP_BUF->flags = TCP_ACK;
|
|
goto tcp_send_noopts;
|
|
}
|
|
}
|
|
goto drop;
|
|
case UIP_LAST_ACK:
|
|
/* We can close this connection if the peer has acknowledged our
|
|
FIN. This is indicated by the UIP_ACKDATA flag. */
|
|
if(uip_flags & UIP_ACKDATA) {
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
|
uip_flags = UIP_CLOSE;
|
|
UIP_APPCALL();
|
|
}
|
|
break;
|
|
|
|
case UIP_FIN_WAIT_1:
|
|
/* The application has closed the connection, but the remote host
|
|
hasn't closed its end yet. Thus we do nothing but wait for a
|
|
FIN from the other side. */
|
|
if(uip_len > 0) {
|
|
uip_add_rcv_nxt(uip_len);
|
|
}
|
|
if(UIP_TCP_BUF->flags & TCP_FIN) {
|
|
if(uip_flags & UIP_ACKDATA) {
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
|
uip_connr->timer = 0;
|
|
uip_connr->len = 0;
|
|
} else {
|
|
uip_connr->tcpstateflags = UIP_CLOSING;
|
|
}
|
|
uip_add_rcv_nxt(1);
|
|
uip_flags = UIP_CLOSE;
|
|
UIP_APPCALL();
|
|
goto tcp_send_ack;
|
|
} else if(uip_flags & UIP_ACKDATA) {
|
|
uip_connr->tcpstateflags = UIP_FIN_WAIT_2;
|
|
uip_connr->len = 0;
|
|
goto drop;
|
|
}
|
|
if(uip_len > 0) {
|
|
goto tcp_send_ack;
|
|
}
|
|
goto drop;
|
|
|
|
case UIP_FIN_WAIT_2:
|
|
if(uip_len > 0) {
|
|
uip_add_rcv_nxt(uip_len);
|
|
}
|
|
if(UIP_TCP_BUF->flags & TCP_FIN) {
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
|
uip_connr->timer = 0;
|
|
uip_add_rcv_nxt(1);
|
|
uip_flags = UIP_CLOSE;
|
|
UIP_APPCALL();
|
|
goto tcp_send_ack;
|
|
}
|
|
if(uip_len > 0) {
|
|
goto tcp_send_ack;
|
|
}
|
|
goto drop;
|
|
|
|
case UIP_TIME_WAIT:
|
|
goto tcp_send_ack;
|
|
|
|
case UIP_CLOSING:
|
|
if(uip_flags & UIP_ACKDATA) {
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
|
uip_connr->timer = 0;
|
|
}
|
|
}
|
|
goto drop;
|
|
|
|
/* We jump here when we are ready to send the packet, and just want
|
|
to set the appropriate TCP sequence numbers in the TCP header. */
|
|
tcp_send_ack:
|
|
UIP_TCP_BUF->flags = TCP_ACK;
|
|
|
|
tcp_send_nodata:
|
|
uip_len = UIP_IPTCPH_LEN; /* TODO: maybe ext_len??? */
|
|
|
|
tcp_send_noopts:
|
|
UIP_TCP_BUF->tcpoffset = (UIP_TCPH_LEN / 4) << 4;
|
|
|
|
/* We're done with the input processing. We are now ready to send a
|
|
reply. Our job is to fill in all the fields of the TCP and IP
|
|
headers before calculating the checksum and finally send the
|
|
packet. */
|
|
tcp_send:
|
|
PRINTF("In tcp_send\n");
|
|
|
|
UIP_TCP_BUF->ackno[0] = uip_connr->rcv_nxt[0];
|
|
UIP_TCP_BUF->ackno[1] = uip_connr->rcv_nxt[1];
|
|
UIP_TCP_BUF->ackno[2] = uip_connr->rcv_nxt[2];
|
|
UIP_TCP_BUF->ackno[3] = uip_connr->rcv_nxt[3];
|
|
|
|
UIP_TCP_BUF->seqno[0] = uip_connr->snd_nxt[0];
|
|
UIP_TCP_BUF->seqno[1] = uip_connr->snd_nxt[1];
|
|
UIP_TCP_BUF->seqno[2] = uip_connr->snd_nxt[2];
|
|
UIP_TCP_BUF->seqno[3] = uip_connr->snd_nxt[3];
|
|
|
|
UIP_IP_BUF->proto = UIP_PROTO_TCP;
|
|
|
|
UIP_TCP_BUF->srcport = uip_connr->lport;
|
|
UIP_TCP_BUF->destport = uip_connr->rport;
|
|
|
|
|
|
uip_ipaddr_copy(&UIP_IP_BUF->destipaddr, &uip_connr->ripaddr);
|
|
uip_ds6_select_src(&UIP_IP_BUF->srcipaddr,&UIP_IP_BUF->destipaddr);
|
|
PRINTF("Sending TCP packet to");
|
|
PRINT6ADDR(&UIP_IP_BUF->destipaddr);
|
|
PRINTF("from");
|
|
PRINT6ADDR(&UIP_IP_BUF->srcipaddr);
|
|
PRINTF("\n");
|
|
|
|
if(uip_connr->tcpstateflags & UIP_STOPPED) {
|
|
/* If the connection has issued uip_stop(), we advertise a zero
|
|
window so that the remote host will stop sending data. */
|
|
UIP_TCP_BUF->wnd[0] = UIP_TCP_BUF->wnd[1] = 0;
|
|
} else {
|
|
UIP_TCP_BUF->wnd[0] = ((UIP_RECEIVE_WINDOW) >> 8);
|
|
UIP_TCP_BUF->wnd[1] = ((UIP_RECEIVE_WINDOW) & 0xff);
|
|
}
|
|
|
|
tcp_send_noconn:
|
|
UIP_IP_BUF->ttl = uip_ds6_if.cur_hop_limit;
|
|
UIP_IP_BUF->len[0] = ((uip_len - UIP_IPH_LEN) >> 8);
|
|
UIP_IP_BUF->len[1] = ((uip_len - UIP_IPH_LEN) & 0xff);
|
|
|
|
UIP_TCP_BUF->urgp[0] = UIP_TCP_BUF->urgp[1] = 0;
|
|
|
|
/* Calculate TCP checksum. */
|
|
UIP_TCP_BUF->tcpchksum = 0;
|
|
UIP_TCP_BUF->tcpchksum = ~(uip_tcpchksum());
|
|
UIP_STAT(++uip_stat.tcp.sent);
|
|
|
|
#endif /* UIP_TCP */
|
|
#if UIP_UDP
|
|
ip_send_nolen:
|
|
#endif
|
|
UIP_IP_BUF->vtc = 0x60;
|
|
UIP_IP_BUF->tcflow = 0x00;
|
|
UIP_IP_BUF->flow = 0x00;
|
|
send:
|
|
PRINTF("Sending packet with length %d (%d)\n", uip_len,
|
|
(UIP_IP_BUF->len[0] << 8) | UIP_IP_BUF->len[1]);
|
|
|
|
UIP_STAT(++uip_stat.ip.sent);
|
|
/* Return and let the caller do the actual transmission. */
|
|
uip_flags = 0;
|
|
return;
|
|
|
|
drop:
|
|
uip_len = 0;
|
|
uip_ext_len = 0;
|
|
uip_ext_bitmap = 0;
|
|
uip_flags = 0;
|
|
return;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
u16_t
|
|
uip_htons(u16_t val)
|
|
{
|
|
return UIP_HTONS(val);
|
|
}
|
|
|
|
u32_t
|
|
uip_htonl(u32_t val)
|
|
{
|
|
return UIP_HTONL(val);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
uip_send(const void *data, int len)
|
|
{
|
|
int copylen;
|
|
#define MIN(a,b) ((a) < (b)? (a): (b))
|
|
copylen = MIN(len, UIP_BUFSIZE - UIP_LLH_LEN - UIP_TCPIP_HLEN -
|
|
(int)((char *)uip_sappdata - (char *)&uip_buf[UIP_LLH_LEN + UIP_TCPIP_HLEN]));
|
|
if(copylen > 0) {
|
|
uip_slen = copylen;
|
|
if(data != uip_sappdata) {
|
|
memcpy(uip_sappdata, (data), uip_slen);
|
|
}
|
|
}
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
/** @} */
|