| 1 |
606 |
jeremybenn |
//#define DEBUG_PRINTF( ... ) /*printf(__VA_ARGS__)*/
|
| 2 |
|
|
|
| 3 |
|
|
/**
|
| 4 |
|
|
* \addtogroup uip
|
| 5 |
|
|
* @{
|
| 6 |
|
|
*/
|
| 7 |
|
|
|
| 8 |
|
|
/**
|
| 9 |
|
|
* \file
|
| 10 |
|
|
* The uIP TCP/IP stack code.
|
| 11 |
|
|
* \author Adam Dunkels <adam@dunkels.com>
|
| 12 |
|
|
*/
|
| 13 |
|
|
|
| 14 |
|
|
/*
|
| 15 |
|
|
* Copyright (c) 2001-2003, Adam Dunkels.
|
| 16 |
|
|
* All rights reserved.
|
| 17 |
|
|
*
|
| 18 |
|
|
* Redistribution and use in source and binary forms, with or without
|
| 19 |
|
|
* modification, are permitted provided that the following conditions
|
| 20 |
|
|
* are met:
|
| 21 |
|
|
* 1. Redistributions of source code must retain the above copyright
|
| 22 |
|
|
* notice, this list of conditions and the following disclaimer.
|
| 23 |
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
| 24 |
|
|
* notice, this list of conditions and the following disclaimer in the
|
| 25 |
|
|
* documentation and/or other materials provided with the distribution.
|
| 26 |
|
|
* 3. The name of the author may not be used to endorse or promote
|
| 27 |
|
|
* products derived from this software without specific prior
|
| 28 |
|
|
* written permission.
|
| 29 |
|
|
*
|
| 30 |
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
|
| 31 |
|
|
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
| 32 |
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
| 33 |
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
|
| 34 |
|
|
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
| 35 |
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
|
| 36 |
|
|
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
| 37 |
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
| 38 |
|
|
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
| 39 |
|
|
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
| 40 |
|
|
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
| 41 |
|
|
*
|
| 42 |
|
|
* This file is part of the uIP TCP/IP stack.
|
| 43 |
|
|
*
|
| 44 |
|
|
* $Id: uip.c 2 2011-07-17 20:13:17Z filepang@gmail.com $
|
| 45 |
|
|
*
|
| 46 |
|
|
*/
|
| 47 |
|
|
|
| 48 |
|
|
/*
|
| 49 |
|
|
* uIP is a small implementation of the IP, UDP and TCP protocols (as
|
| 50 |
|
|
* well as some basic ICMP stuff). The implementation couples the IP,
|
| 51 |
|
|
* UDP, TCP and the application layers very tightly. To keep the size
|
| 52 |
|
|
* of the compiled code down, this code frequently uses the goto
|
| 53 |
|
|
* statement. While it would be possible to break the uip_process()
|
| 54 |
|
|
* function into many smaller functions, this would increase the code
|
| 55 |
|
|
* size because of the overhead of parameter passing and the fact that
|
| 56 |
|
|
* the optimier would not be as efficient.
|
| 57 |
|
|
*
|
| 58 |
|
|
* The principle is that we have a small buffer, called the uip_buf,
|
| 59 |
|
|
* in which the device driver puts an incoming packet. The TCP/IP
|
| 60 |
|
|
* stack parses the headers in the packet, and calls the
|
| 61 |
|
|
* application. If the remote host has sent data to the application,
|
| 62 |
|
|
* this data is present in the uip_buf and the application read the
|
| 63 |
|
|
* data from there. It is up to the application to put this data into
|
| 64 |
|
|
* a byte stream if needed. The application will not be fed with data
|
| 65 |
|
|
* that is out of sequence.
|
| 66 |
|
|
*
|
| 67 |
|
|
* If the application whishes to send data to the peer, it should put
|
| 68 |
|
|
* its data into the uip_buf. The uip_appdata pointer points to the
|
| 69 |
|
|
* first available byte. The TCP/IP stack will calculate the
|
| 70 |
|
|
* checksums, and fill in the necessary header fields and finally send
|
| 71 |
|
|
* the packet back to the peer.
|
| 72 |
|
|
*/
|
| 73 |
|
|
#include "net/uip.h"
|
| 74 |
|
|
#include "net/uipopt.h"
|
| 75 |
|
|
#include "net/uip_arp.h"
|
| 76 |
|
|
#include "net/uip_arch.h"
|
| 77 |
|
|
|
| 78 |
|
|
/* If UIP_CONF_IPV6 is defined, we compile the uip6.c file instead of this one.
|
| 79 |
|
|
Therefore this #ifndef removes the entire compilation output of the uip.c file */
|
| 80 |
|
|
#if !UIP_CONF_IPV6
|
| 81 |
|
|
|
| 82 |
|
|
#if UIP_CONF_IPV6
|
| 83 |
|
|
#include "net/uip-neighbor.h"
|
| 84 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 85 |
|
|
|
| 86 |
|
|
#include <string.h>
|
| 87 |
|
|
|
| 88 |
|
|
/*---------------------------------------------------------------------------*/
|
| 89 |
|
|
|
| 90 |
|
|
/* Variable definitions. */
|
| 91 |
|
|
|
| 92 |
|
|
/* The IP address of this host. If it is defined to be fixed (by setting
|
| 93 |
|
|
UIP_FIXEDADDR to 1 in uipopt.h), the address is set here. Otherwise, the address */
|
| 94 |
|
|
#if UIP_FIXEDADDR > 0
|
| 95 |
|
|
const uip_ipaddr_t uip_hostaddr = { UIP_IPADDR0, UIP_IPADDR1, UIP_IPADDR2, UIP_IPADDR3 };
|
| 96 |
|
|
const uip_ipaddr_t uip_draddr = { UIP_DRIPADDR0, UIP_DRIPADDR1, UIP_DRIPADDR2, UIP_DRIPADDR3 };
|
| 97 |
|
|
const uip_ipaddr_t uip_netmask = { UIP_NETMASK0, UIP_NETMASK1, UIP_NETMASK2, UIP_NETMASK3 };
|
| 98 |
|
|
#else
|
| 99 |
|
|
uip_ipaddr_t uip_hostaddr, uip_draddr, uip_netmask;
|
| 100 |
|
|
#endif /* UIP_FIXEDADDR */
|
| 101 |
|
|
|
| 102 |
|
|
const uip_ipaddr_t uip_broadcast_addr =
|
| 103 |
|
|
#if UIP_CONF_IPV6
|
| 104 |
|
|
{ { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff } };
|
| 105 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 106 |
|
|
{ { 0xff, 0xff, 0xff, 0xff } };
|
| 107 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 108 |
|
|
|
| 109 |
|
|
const uip_ipaddr_t uip_all_zeroes_addr = { { 0x0, /* rest is 0 */ } };
|
| 110 |
|
|
|
| 111 |
|
|
#if UIP_FIXEDETHADDR
|
| 112 |
|
|
const struct uip_eth_addr uip_ethaddr = { { UIP_ETHADDR0, UIP_ETHADDR1, UIP_ETHADDR2, UIP_ETHADDR3, UIP_ETHADDR4, UIP_ETHADDR5 } };
|
| 113 |
|
|
#else
|
| 114 |
|
|
struct uip_eth_addr uip_ethaddr = { { 0, 0, 0, 0, 0, 0 } };
|
| 115 |
|
|
#endif
|
| 116 |
|
|
|
| 117 |
|
|
#ifndef UIP_CONF_EXTERNAL_BUFFER
|
| 118 |
|
|
/* The packet buffer that contains incoming packets. */
|
| 119 |
|
|
u8_t uip_buf[ UIP_BUFSIZE + 2 ];
|
| 120 |
|
|
#endif /* UIP_CONF_EXTERNAL_BUFFER */
|
| 121 |
|
|
|
| 122 |
|
|
/* The uip_appdata pointer points to application data. */
|
| 123 |
|
|
void *uip_appdata;
|
| 124 |
|
|
|
| 125 |
|
|
/* The uip_appdata pointer points to the application data which is to be sent. */
|
| 126 |
|
|
void *uip_sappdata;
|
| 127 |
|
|
|
| 128 |
|
|
#if UIP_URGDATA > 0
|
| 129 |
|
|
/* The uip_urgdata pointer points to urgent data (out-of-band data), if
|
| 130 |
|
|
present. */
|
| 131 |
|
|
void *uip_urgdata;
|
| 132 |
|
|
u16_t uip_urglen, uip_surglen;
|
| 133 |
|
|
#endif /* UIP_URGDATA > 0 */
|
| 134 |
|
|
|
| 135 |
|
|
/* The uip_len is either 8 or 16 bits, depending on the maximum packet size. */
|
| 136 |
|
|
u16_t uip_len, uip_slen;
|
| 137 |
|
|
|
| 138 |
|
|
/* The uip_flags variable is used for communication between the TCP/IP stack
|
| 139 |
|
|
and the application program. */
|
| 140 |
|
|
u8_t uip_flags;
|
| 141 |
|
|
|
| 142 |
|
|
/* uip_conn always points to the current connection. */
|
| 143 |
|
|
struct uip_conn *uip_conn;
|
| 144 |
|
|
struct uip_conn uip_conns[ UIP_CONNS ];
|
| 145 |
|
|
|
| 146 |
|
|
/* The uip_conns array holds all TCP connections. */
|
| 147 |
|
|
u16_t uip_listenports[UIP_LISTENPORTS];
|
| 148 |
|
|
|
| 149 |
|
|
/* The uip_listenports list all currently listning ports. */
|
| 150 |
|
|
#if UIP_UDP
|
| 151 |
|
|
struct uip_udp_conn *uip_udp_conn;
|
| 152 |
|
|
struct uip_udp_conn uip_udp_conns[UIP_UDP_CONNS];
|
| 153 |
|
|
#endif /* UIP_UDP */
|
| 154 |
|
|
|
| 155 |
|
|
/* Ths ipid variable is an increasing number that is used for the IP ID field. */
|
| 156 |
|
|
static u16_t ipid;
|
| 157 |
|
|
|
| 158 |
|
|
void uip_setipid( u16_t id )
|
| 159 |
|
|
{
|
| 160 |
|
|
ipid = id;
|
| 161 |
|
|
}
|
| 162 |
|
|
|
| 163 |
|
|
/* The iss variable is used for the TCP initial sequence number. */
|
| 164 |
|
|
static u8_t iss[ 4 ];
|
| 165 |
|
|
|
| 166 |
|
|
#if UIP_ACTIVE_OPEN
|
| 167 |
|
|
/* Keeps track of the last port used for a new connection. */
|
| 168 |
|
|
static u16_t lastport;
|
| 169 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 170 |
|
|
|
| 171 |
|
|
/* Temporary variables. */
|
| 172 |
|
|
u8_t uip_acc32[ 4 ];
|
| 173 |
|
|
static u8_t c, opt;
|
| 174 |
|
|
static u16_t tmp16;
|
| 175 |
|
|
|
| 176 |
|
|
/* Structures and definitions. */
|
| 177 |
|
|
#define TCP_FIN 0x01
|
| 178 |
|
|
#define TCP_SYN 0x02
|
| 179 |
|
|
#define TCP_RST 0x04
|
| 180 |
|
|
#define TCP_PSH 0x08
|
| 181 |
|
|
#define TCP_ACK 0x10
|
| 182 |
|
|
#define TCP_URG 0x20
|
| 183 |
|
|
#define TCP_CTL 0x3f
|
| 184 |
|
|
|
| 185 |
|
|
#define TCP_OPT_END 0 /* End of TCP options list */
|
| 186 |
|
|
#define TCP_OPT_NOOP 1 /* "No-operation" TCP option */
|
| 187 |
|
|
#define TCP_OPT_MSS 2 /* Maximum segment size TCP option */
|
| 188 |
|
|
|
| 189 |
|
|
#define TCP_OPT_MSS_LEN 4 /* Length of TCP MSS option. */
|
| 190 |
|
|
|
| 191 |
|
|
#define ICMP_ECHO_REPLY 0
|
| 192 |
|
|
#define ICMP_ECHO 8
|
| 193 |
|
|
|
| 194 |
|
|
#define ICMP_DEST_UNREACHABLE 3
|
| 195 |
|
|
#define ICMP_PORT_UNREACHABLE 3
|
| 196 |
|
|
|
| 197 |
|
|
#define ICMP6_ECHO_REPLY 129
|
| 198 |
|
|
#define ICMP6_ECHO 128
|
| 199 |
|
|
#define ICMP6_NEIGHBOR_SOLICITATION 135
|
| 200 |
|
|
#define ICMP6_NEIGHBOR_ADVERTISEMENT 136
|
| 201 |
|
|
|
| 202 |
|
|
#define ICMP6_FLAG_S ( 1 << 6 )
|
| 203 |
|
|
#define ICMP6_OPTION_SOURCE_LINK_ADDRESS 1
|
| 204 |
|
|
#define ICMP6_OPTION_TARGET_LINK_ADDRESS 2
|
| 205 |
|
|
|
| 206 |
|
|
/* Macros. */
|
| 207 |
|
|
#define BUF ( ( struct uip_tcpip_hdr * ) &uip_buf[UIP_LLH_LEN] )
|
| 208 |
|
|
#define FBUF ( ( struct uip_tcpip_hdr * ) &uip_reassbuf[0] )
|
| 209 |
|
|
#define ICMPBUF ( ( struct uip_icmpip_hdr * ) &uip_buf[UIP_LLH_LEN] )
|
| 210 |
|
|
#define UDPBUF ( ( struct uip_udpip_hdr * ) &uip_buf[UIP_LLH_LEN] )
|
| 211 |
|
|
|
| 212 |
|
|
#if UIP_STATISTICS == 1
|
| 213 |
|
|
struct uip_stats uip_stat;
|
| 214 |
|
|
#define UIP_STAT( s ) s
|
| 215 |
|
|
#else
|
| 216 |
|
|
#define UIP_STAT( s )
|
| 217 |
|
|
#endif /* UIP_STATISTICS == 1 */
|
| 218 |
|
|
|
| 219 |
|
|
#if UIP_LOGGING == 1
|
| 220 |
|
|
#include <stdio.h>
|
| 221 |
|
|
void uip_log( char *msg );
|
| 222 |
|
|
#define UIP_LOG( m ) uip_log( m )
|
| 223 |
|
|
#else
|
| 224 |
|
|
#define UIP_LOG( m )
|
| 225 |
|
|
#endif /* UIP_LOGGING == 1 */
|
| 226 |
|
|
|
| 227 |
|
|
#if !UIP_ARCH_ADD32
|
| 228 |
|
|
void uip_add32( u8_t *op32, u16_t op16 )
|
| 229 |
|
|
{
|
| 230 |
|
|
uip_acc32[3] = op32[3] + ( op16 & 0xff );
|
| 231 |
|
|
uip_acc32[2] = op32[2] + ( op16 >> 8 );
|
| 232 |
|
|
uip_acc32[1] = op32[1];
|
| 233 |
|
|
uip_acc32[0] = op32[0];
|
| 234 |
|
|
|
| 235 |
|
|
if( uip_acc32[2] < (op16 >> 8) )
|
| 236 |
|
|
{
|
| 237 |
|
|
++uip_acc32[1];
|
| 238 |
|
|
if( uip_acc32[1] == 0 )
|
| 239 |
|
|
{
|
| 240 |
|
|
++uip_acc32[0];
|
| 241 |
|
|
}
|
| 242 |
|
|
}
|
| 243 |
|
|
|
| 244 |
|
|
if( uip_acc32[3] < (op16 & 0xff) )
|
| 245 |
|
|
{
|
| 246 |
|
|
++uip_acc32[2];
|
| 247 |
|
|
if( uip_acc32[2] == 0 )
|
| 248 |
|
|
{
|
| 249 |
|
|
++uip_acc32[1];
|
| 250 |
|
|
if( uip_acc32[1] == 0 )
|
| 251 |
|
|
{
|
| 252 |
|
|
++uip_acc32[0];
|
| 253 |
|
|
}
|
| 254 |
|
|
}
|
| 255 |
|
|
}
|
| 256 |
|
|
}
|
| 257 |
|
|
/*---------------------------------------------------------------------------*/
|
| 258 |
|
|
#endif /* UIP_ARCH_ADD32 */
|
| 259 |
|
|
|
| 260 |
|
|
#if !UIP_ARCH_CHKSUM
|
| 261 |
|
|
|
| 262 |
|
|
static u16_t chksum( u16_t sum, const u8_t *data, u16_t len )
|
| 263 |
|
|
{
|
| 264 |
|
|
u16_t t;
|
| 265 |
|
|
const u8_t *dataptr;
|
| 266 |
|
|
const u8_t *last_byte;
|
| 267 |
|
|
|
| 268 |
|
|
dataptr = data;
|
| 269 |
|
|
last_byte = data + len - 1;
|
| 270 |
|
|
|
| 271 |
|
|
while( dataptr < last_byte )
|
| 272 |
|
|
{
|
| 273 |
|
|
/* At least two more bytes */
|
| 274 |
|
|
t = ( dataptr[ 0 ] << 8 ) + dataptr[ 1 ];
|
| 275 |
|
|
sum += t;
|
| 276 |
|
|
if( sum < t )
|
| 277 |
|
|
{
|
| 278 |
|
|
sum++; /* carry */
|
| 279 |
|
|
}
|
| 280 |
|
|
|
| 281 |
|
|
dataptr += 2;
|
| 282 |
|
|
}
|
| 283 |
|
|
|
| 284 |
|
|
if( dataptr == last_byte )
|
| 285 |
|
|
{
|
| 286 |
|
|
t = ( dataptr[ 0 ] << 8 ) + 0;
|
| 287 |
|
|
sum += t;
|
| 288 |
|
|
if( sum < t )
|
| 289 |
|
|
{
|
| 290 |
|
|
sum++; /* carry */
|
| 291 |
|
|
}
|
| 292 |
|
|
}
|
| 293 |
|
|
|
| 294 |
|
|
/* Return sum in host byte order. */
|
| 295 |
|
|
return sum;
|
| 296 |
|
|
}
|
| 297 |
|
|
/*---------------------------------------------------------------------------*/
|
| 298 |
|
|
|
| 299 |
|
|
u16_t uip_chksum( u16_t *data, u16_t len )
|
| 300 |
|
|
{
|
| 301 |
|
|
return htons( chksum( 0, ( u8_t * ) data, len ) );
|
| 302 |
|
|
}
|
| 303 |
|
|
/*---------------------------------------------------------------------------*/
|
| 304 |
|
|
|
| 305 |
|
|
#ifndef UIP_ARCH_IPCHKSUM
|
| 306 |
|
|
u16_t uip_ipchksum( void )
|
| 307 |
|
|
{
|
| 308 |
|
|
u16_t sum;
|
| 309 |
|
|
|
| 310 |
|
|
sum = chksum( 0, &uip_buf[UIP_LLH_LEN], UIP_IPH_LEN );
|
| 311 |
|
|
|
| 312 |
|
|
//DEBUG_PRINTF( "uip_ipchksum: sum 0x%04x\n", sum );
|
| 313 |
|
|
return( sum == 0 ) ? 0xffff : htons( sum );
|
| 314 |
|
|
}
|
| 315 |
|
|
#endif
|
| 316 |
|
|
/*---------------------------------------------------------------------------*/
|
| 317 |
|
|
|
| 318 |
|
|
static u16_t upper_layer_chksum( u8_t proto )
|
| 319 |
|
|
{
|
| 320 |
|
|
u16_t upper_layer_len;
|
| 321 |
|
|
u16_t sum;
|
| 322 |
|
|
|
| 323 |
|
|
#if UIP_CONF_IPV6
|
| 324 |
|
|
upper_layer_len = ( ((u16_t) (BUF->len[ 0 ]) << 8) + BUF->len[ 1 ] );
|
| 325 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 326 |
|
|
upper_layer_len = ( ((u16_t) (BUF->len[ 0 ]) << 8) + BUF->len[ 1 ] ) - UIP_IPH_LEN;
|
| 327 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 328 |
|
|
|
| 329 |
|
|
/* First sum pseudoheader. */
|
| 330 |
|
|
|
| 331 |
|
|
/* IP protocol and length fields. This addition cannot carry. */
|
| 332 |
|
|
sum = upper_layer_len + proto;
|
| 333 |
|
|
|
| 334 |
|
|
/* Sum IP source and destination addresses. */
|
| 335 |
|
|
sum = chksum( sum, ( u8_t * ) &BUF->srcipaddr, 2 * sizeof(uip_ipaddr_t) );
|
| 336 |
|
|
|
| 337 |
|
|
/* Sum TCP header and data. */
|
| 338 |
|
|
sum = chksum( sum, &uip_buf[UIP_IPH_LEN + UIP_LLH_LEN], upper_layer_len );
|
| 339 |
|
|
|
| 340 |
|
|
return( sum == 0 ) ? 0xffff : htons( sum );
|
| 341 |
|
|
}
|
| 342 |
|
|
/*---------------------------------------------------------------------------*/
|
| 343 |
|
|
|
| 344 |
|
|
#if UIP_CONF_IPV6
|
| 345 |
|
|
u16_t uip_icmp6chksum( void )
|
| 346 |
|
|
{
|
| 347 |
|
|
return upper_layer_chksum( UIP_PROTO_ICMP6 );
|
| 348 |
|
|
}
|
| 349 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 350 |
|
|
/*---------------------------------------------------------------------------*/
|
| 351 |
|
|
|
| 352 |
|
|
u16_t uip_tcpchksum( void )
|
| 353 |
|
|
{
|
| 354 |
|
|
return upper_layer_chksum( UIP_PROTO_TCP );
|
| 355 |
|
|
}
|
| 356 |
|
|
/*---------------------------------------------------------------------------*/
|
| 357 |
|
|
|
| 358 |
|
|
#if UIP_UDP_CHECKSUMS
|
| 359 |
|
|
u16_t uip_udpchksum( void )
|
| 360 |
|
|
{
|
| 361 |
|
|
return upper_layer_chksum( UIP_PROTO_UDP );
|
| 362 |
|
|
}
|
| 363 |
|
|
#endif /* UIP_UDP_CHECKSUMS */
|
| 364 |
|
|
|
| 365 |
|
|
#endif /* UIP_ARCH_CHKSUM */
|
| 366 |
|
|
/*---------------------------------------------------------------------------*/
|
| 367 |
|
|
|
| 368 |
|
|
void uip_init( void )
|
| 369 |
|
|
{
|
| 370 |
|
|
for( c = 0; c < UIP_LISTENPORTS; ++c )
|
| 371 |
|
|
{
|
| 372 |
|
|
uip_listenports[ c ] = 0;
|
| 373 |
|
|
}
|
| 374 |
|
|
|
| 375 |
|
|
for( c = 0; c < UIP_CONNS; ++c )
|
| 376 |
|
|
{
|
| 377 |
|
|
uip_conns[ c ].tcpstateflags = UIP_CLOSED;
|
| 378 |
|
|
}
|
| 379 |
|
|
|
| 380 |
|
|
#if UIP_ACTIVE_OPEN
|
| 381 |
|
|
lastport = 1024;
|
| 382 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 383 |
|
|
|
| 384 |
|
|
#if UIP_UDP
|
| 385 |
|
|
for( c = 0; c < UIP_UDP_CONNS; ++c )
|
| 386 |
|
|
{
|
| 387 |
|
|
uip_udp_conns[ c ].lport = 0;
|
| 388 |
|
|
}
|
| 389 |
|
|
#endif /* UIP_UDP */
|
| 390 |
|
|
|
| 391 |
|
|
/* IPv4 initialization. */
|
| 392 |
|
|
#if UIP_FIXEDADDR == 0
|
| 393 |
|
|
/* uip_hostaddr[ 0 ] = uip_hostaddr[ 1 ] = 0;*/
|
| 394 |
|
|
#endif /* UIP_FIXEDADDR */
|
| 395 |
|
|
}
|
| 396 |
|
|
/*---------------------------------------------------------------------------*/
|
| 397 |
|
|
|
| 398 |
|
|
#if UIP_ACTIVE_OPEN
|
| 399 |
|
|
struct uip_conn *uip_connect( uip_ipaddr_t *ripaddr, u16_t rport )
|
| 400 |
|
|
{
|
| 401 |
|
|
register struct uip_conn *conn, *cconn;
|
| 402 |
|
|
|
| 403 |
|
|
/* Find an unused local port. */
|
| 404 |
|
|
again:
|
| 405 |
|
|
++lastport;
|
| 406 |
|
|
|
| 407 |
|
|
if( lastport >= 32000 )
|
| 408 |
|
|
{
|
| 409 |
|
|
lastport = 4096;
|
| 410 |
|
|
}
|
| 411 |
|
|
|
| 412 |
|
|
/* Check if this port is already in use, and if so try to find
|
| 413 |
|
|
another one. */
|
| 414 |
|
|
for( c = 0; c < UIP_CONNS; ++c )
|
| 415 |
|
|
{
|
| 416 |
|
|
conn = &uip_conns[ c ];
|
| 417 |
|
|
if( conn->tcpstateflags != UIP_CLOSED && conn->lport == htons(lastport) )
|
| 418 |
|
|
{
|
| 419 |
|
|
goto again;
|
| 420 |
|
|
}
|
| 421 |
|
|
}
|
| 422 |
|
|
|
| 423 |
|
|
conn = 0;
|
| 424 |
|
|
for( c = 0; c < UIP_CONNS; ++c )
|
| 425 |
|
|
{
|
| 426 |
|
|
cconn = &uip_conns[ c ];
|
| 427 |
|
|
if( cconn->tcpstateflags == UIP_CLOSED )
|
| 428 |
|
|
{
|
| 429 |
|
|
conn = cconn;
|
| 430 |
|
|
break;
|
| 431 |
|
|
}
|
| 432 |
|
|
|
| 433 |
|
|
if( cconn->tcpstateflags == UIP_TIME_WAIT )
|
| 434 |
|
|
{
|
| 435 |
|
|
if( conn == 0 || cconn->timer > conn->timer )
|
| 436 |
|
|
{
|
| 437 |
|
|
conn = cconn;
|
| 438 |
|
|
}
|
| 439 |
|
|
}
|
| 440 |
|
|
}
|
| 441 |
|
|
|
| 442 |
|
|
if( conn == 0 )
|
| 443 |
|
|
{
|
| 444 |
|
|
return 0;
|
| 445 |
|
|
}
|
| 446 |
|
|
|
| 447 |
|
|
conn->tcpstateflags = UIP_SYN_SENT;
|
| 448 |
|
|
|
| 449 |
|
|
conn->snd_nxt[ 0 ] = iss[ 0 ];
|
| 450 |
|
|
conn->snd_nxt[ 1 ] = iss[ 1 ];
|
| 451 |
|
|
conn->snd_nxt[ 2 ] = iss[ 2 ];
|
| 452 |
|
|
conn->snd_nxt[ 3 ] = iss[ 3 ];
|
| 453 |
|
|
|
| 454 |
|
|
conn->initialmss = conn->mss = UIP_TCP_MSS;
|
| 455 |
|
|
|
| 456 |
|
|
conn->len = 1; /* TCP length of the SYN is one. */
|
| 457 |
|
|
conn->nrtx = 0;
|
| 458 |
|
|
conn->timer = 1; /* Send the SYN next time around. */
|
| 459 |
|
|
conn->rto = UIP_RTO;
|
| 460 |
|
|
conn->sa = 0;
|
| 461 |
|
|
conn->sv = 16; /* Initial value of the RTT variance. */
|
| 462 |
|
|
conn->lport = htons( lastport );
|
| 463 |
|
|
conn->rport = rport;
|
| 464 |
|
|
uip_ipaddr_copy( &conn->ripaddr, ripaddr );
|
| 465 |
|
|
|
| 466 |
|
|
return conn;
|
| 467 |
|
|
}
|
| 468 |
|
|
/*---------------------------------------------------------------------------*/
|
| 469 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 470 |
|
|
|
| 471 |
|
|
#if UIP_UDP
|
| 472 |
|
|
struct uip_udp_conn *uip_udp_new( const uip_ipaddr_t *ripaddr, u16_t rport )
|
| 473 |
|
|
{
|
| 474 |
|
|
register struct uip_udp_conn *conn;
|
| 475 |
|
|
|
| 476 |
|
|
/* Find an unused local port. */
|
| 477 |
|
|
again:
|
| 478 |
|
|
++lastport;
|
| 479 |
|
|
|
| 480 |
|
|
if( lastport >= 32000 )
|
| 481 |
|
|
{
|
| 482 |
|
|
lastport = 4096;
|
| 483 |
|
|
}
|
| 484 |
|
|
|
| 485 |
|
|
for( c = 0; c < UIP_UDP_CONNS; ++c )
|
| 486 |
|
|
{
|
| 487 |
|
|
if( uip_udp_conns[ c ].lport == htons(lastport) )
|
| 488 |
|
|
{
|
| 489 |
|
|
goto again;
|
| 490 |
|
|
}
|
| 491 |
|
|
}
|
| 492 |
|
|
|
| 493 |
|
|
conn = 0;
|
| 494 |
|
|
for( c = 0; c < UIP_UDP_CONNS; ++c )
|
| 495 |
|
|
{
|
| 496 |
|
|
if( uip_udp_conns[ c ].lport == 0 )
|
| 497 |
|
|
{
|
| 498 |
|
|
conn = &uip_udp_conns[ c ];
|
| 499 |
|
|
break;
|
| 500 |
|
|
}
|
| 501 |
|
|
}
|
| 502 |
|
|
|
| 503 |
|
|
if( conn == 0 )
|
| 504 |
|
|
{
|
| 505 |
|
|
return 0;
|
| 506 |
|
|
}
|
| 507 |
|
|
|
| 508 |
|
|
conn->lport = HTONS( lastport );
|
| 509 |
|
|
conn->rport = rport;
|
| 510 |
|
|
if( ripaddr == NULL )
|
| 511 |
|
|
{
|
| 512 |
|
|
memset( &conn->ripaddr, 0, sizeof(uip_ipaddr_t) );
|
| 513 |
|
|
}
|
| 514 |
|
|
else
|
| 515 |
|
|
{
|
| 516 |
|
|
uip_ipaddr_copy( &conn->ripaddr, ripaddr );
|
| 517 |
|
|
}
|
| 518 |
|
|
|
| 519 |
|
|
conn->ttl = UIP_TTL;
|
| 520 |
|
|
|
| 521 |
|
|
return conn;
|
| 522 |
|
|
}
|
| 523 |
|
|
/*---------------------------------------------------------------------------*/
|
| 524 |
|
|
#endif /* UIP_UDP */
|
| 525 |
|
|
|
| 526 |
|
|
void uip_unlisten( u16_t port )
|
| 527 |
|
|
{
|
| 528 |
|
|
for( c = 0; c < UIP_LISTENPORTS; ++c )
|
| 529 |
|
|
{
|
| 530 |
|
|
if( uip_listenports[ c ] == port )
|
| 531 |
|
|
{
|
| 532 |
|
|
uip_listenports[ c ] = 0;
|
| 533 |
|
|
return;
|
| 534 |
|
|
}
|
| 535 |
|
|
}
|
| 536 |
|
|
}
|
| 537 |
|
|
/*---------------------------------------------------------------------------*/
|
| 538 |
|
|
|
| 539 |
|
|
void uip_listen( u16_t port )
|
| 540 |
|
|
{
|
| 541 |
|
|
for( c = 0; c < UIP_LISTENPORTS; ++c )
|
| 542 |
|
|
{
|
| 543 |
|
|
if( uip_listenports[ c ] == 0 )
|
| 544 |
|
|
{
|
| 545 |
|
|
uip_listenports[ c ] = port;
|
| 546 |
|
|
return;
|
| 547 |
|
|
}
|
| 548 |
|
|
}
|
| 549 |
|
|
}
|
| 550 |
|
|
/*---------------------------------------------------------------------------*/
|
| 551 |
|
|
|
| 552 |
|
|
/* XXX: IP fragment reassembly: not well-tested. */
|
| 553 |
|
|
#if UIP_REASSEMBLY && !UIP_CONF_IPV6
|
| 554 |
|
|
#define UIP_REASS_BUFSIZE ( UIP_BUFSIZE - UIP_LLH_LEN )
|
| 555 |
|
|
static u8_t uip_reassbuf[UIP_REASS_BUFSIZE];
|
| 556 |
|
|
static u8_t uip_reassbitmap[UIP_REASS_BUFSIZE / ( 8 * 8 )];
|
| 557 |
|
|
static const u8_t bitmap_bits[8] = { 0xff, 0x7f, 0x3f, 0x1f, 0x0f, 0x07, 0x03, 0x01 };
|
| 558 |
|
|
static u16_t uip_reasslen;
|
| 559 |
|
|
static u8_t uip_reassflags;
|
| 560 |
|
|
#define UIP_REASS_FLAG_LASTFRAG 0x01
|
| 561 |
|
|
static u8_t uip_reasstmr;
|
| 562 |
|
|
|
| 563 |
|
|
#define IP_MF 0x20
|
| 564 |
|
|
|
| 565 |
|
|
static u8_t uip_reass( void )
|
| 566 |
|
|
{
|
| 567 |
|
|
u16_t offset, len;
|
| 568 |
|
|
u16_t i;
|
| 569 |
|
|
|
| 570 |
|
|
/* If ip_reasstmr is zero, no packet is present in the buffer, so we
|
| 571 |
|
|
write the IP header of the fragment into the reassembly
|
| 572 |
|
|
buffer. The timer is updated with the maximum age. */
|
| 573 |
|
|
if( uip_reasstmr == 0 )
|
| 574 |
|
|
{
|
| 575 |
|
|
memcpy( uip_reassbuf, &BUF->vhl, UIP_IPH_LEN );
|
| 576 |
|
|
uip_reasstmr = UIP_REASS_MAXAGE;
|
| 577 |
|
|
uip_reassflags = 0;
|
| 578 |
|
|
|
| 579 |
|
|
/* Clear the bitmap. */
|
| 580 |
|
|
memset( uip_reassbitmap, 0, sizeof(uip_reassbitmap) );
|
| 581 |
|
|
}
|
| 582 |
|
|
|
| 583 |
|
|
/* Check if the incoming fragment matches the one currently present
|
| 584 |
|
|
in the reasembly buffer. If so, we proceed with copying the
|
| 585 |
|
|
fragment into the buffer. */
|
| 586 |
|
|
if
|
| 587 |
|
|
(
|
| 588 |
|
|
BUF->srcipaddr[ 0 ] == FBUF->srcipaddr[ 0 ] &&
|
| 589 |
|
|
BUF->srcipaddr[ 1 ] == FBUF->srcipaddr[ 1 ] &&
|
| 590 |
|
|
BUF->destipaddr[ 0 ] == FBUF->destipaddr[ 0 ] &&
|
| 591 |
|
|
BUF->destipaddr[ 1 ] == FBUF->destipaddr[ 1 ] &&
|
| 592 |
|
|
BUF->ipid[ 0 ] == FBUF->ipid[ 0 ] &&
|
| 593 |
|
|
BUF->ipid[ 1 ] == FBUF->ipid[ 1 ]
|
| 594 |
|
|
)
|
| 595 |
|
|
{
|
| 596 |
|
|
len = ( BUF->len[ 0 ] << 8 ) + BUF->len[ 1 ] - ( BUF->vhl & 0x0f ) * 4;
|
| 597 |
|
|
offset = ( ((BUF->ipoffset[ 0 ] & 0x3f) << 8) + BUF->ipoffset[ 1 ] ) * 8;
|
| 598 |
|
|
|
| 599 |
|
|
/* If the offset or the offset + fragment length overflows the
|
| 600 |
|
|
reassembly buffer, we discard the entire packet. */
|
| 601 |
|
|
if( offset > UIP_REASS_BUFSIZE || offset + len > UIP_REASS_BUFSIZE )
|
| 602 |
|
|
{
|
| 603 |
|
|
uip_reasstmr = 0;
|
| 604 |
|
|
goto nullreturn;
|
| 605 |
|
|
}
|
| 606 |
|
|
|
| 607 |
|
|
/* Copy the fragment into the reassembly buffer, at the right
|
| 608 |
|
|
offset. */
|
| 609 |
|
|
memcpy( &uip_reassbuf[UIP_IPH_LEN + offset], ( char * ) BUF + ( int ) ((BUF->vhl & 0x0f) * 4), len );
|
| 610 |
|
|
|
| 611 |
|
|
/* Update the bitmap. */
|
| 612 |
|
|
if( offset / (8 * 8) == (offset + len) / (8 * 8) )
|
| 613 |
|
|
{
|
| 614 |
|
|
/* If the two endpoints are in the same byte, we only update
|
| 615 |
|
|
that byte. */
|
| 616 |
|
|
uip_reassbitmap[offset / ( 8 * 8 )] |= bitmap_bits[( offset / 8 ) & 7] &~bitmap_bits[( (offset + len) / 8 ) & 7];
|
| 617 |
|
|
}
|
| 618 |
|
|
else
|
| 619 |
|
|
{
|
| 620 |
|
|
/* If the two endpoints are in different bytes, we update the
|
| 621 |
|
|
bytes in the endpoints and fill the stuff inbetween with
|
| 622 |
|
|
0xff. */
|
| 623 |
|
|
uip_reassbitmap[offset / ( 8 * 8 )] |= bitmap_bits[( offset / 8 ) & 7];
|
| 624 |
|
|
for( i = 1 + offset / (8 * 8); i < (offset + len) / (8 * 8); ++i )
|
| 625 |
|
|
{
|
| 626 |
|
|
uip_reassbitmap[i] = 0xff;
|
| 627 |
|
|
}
|
| 628 |
|
|
|
| 629 |
|
|
uip_reassbitmap[( offset + len ) / ( 8 * 8 )] |= ~bitmap_bits[( (offset + len) / 8 ) & 7];
|
| 630 |
|
|
}
|
| 631 |
|
|
|
| 632 |
|
|
/* If this fragment has the More Fragments flag set to zero, we
|
| 633 |
|
|
know that this is the last fragment, so we can calculate the
|
| 634 |
|
|
size of the entire packet. We also set the
|
| 635 |
|
|
IP_REASS_FLAG_LASTFRAG flag to indicate that we have received
|
| 636 |
|
|
the final fragment. */
|
| 637 |
|
|
if( (BUF->ipoffset[ 0 ] & IP_MF) == 0 )
|
| 638 |
|
|
{
|
| 639 |
|
|
uip_reassflags |= UIP_REASS_FLAG_LASTFRAG;
|
| 640 |
|
|
uip_reasslen = offset + len;
|
| 641 |
|
|
}
|
| 642 |
|
|
|
| 643 |
|
|
/* Finally, we check if we have a full packet in the buffer. We do
|
| 644 |
|
|
this by checking if we have the last fragment and if all bits
|
| 645 |
|
|
in the bitmap are set. */
|
| 646 |
|
|
if( uip_reassflags & UIP_REASS_FLAG_LASTFRAG )
|
| 647 |
|
|
{
|
| 648 |
|
|
/* Check all bytes up to and including all but the last byte in
|
| 649 |
|
|
the bitmap. */
|
| 650 |
|
|
for( i = 0; i < uip_reasslen / (8 * 8) - 1; ++i )
|
| 651 |
|
|
{
|
| 652 |
|
|
if( uip_reassbitmap[i] != 0xff )
|
| 653 |
|
|
{
|
| 654 |
|
|
goto nullreturn;
|
| 655 |
|
|
}
|
| 656 |
|
|
}
|
| 657 |
|
|
|
| 658 |
|
|
/* Check the last byte in the bitmap. It should contain just the
|
| 659 |
|
|
right amount of bits. */
|
| 660 |
|
|
if( uip_reassbitmap[uip_reasslen / (8 * 8)] != (u8_t)~bitmap_bits[uip_reasslen / 8 & 7] )
|
| 661 |
|
|
{
|
| 662 |
|
|
goto nullreturn;
|
| 663 |
|
|
}
|
| 664 |
|
|
|
| 665 |
|
|
/* If we have come this far, we have a full packet in the
|
| 666 |
|
|
buffer, so we allocate a pbuf and copy the packet into it. We
|
| 667 |
|
|
also reset the timer. */
|
| 668 |
|
|
uip_reasstmr = 0;
|
| 669 |
|
|
memcpy( BUF, FBUF, uip_reasslen );
|
| 670 |
|
|
|
| 671 |
|
|
/* Pretend to be a "normal" (i.e., not fragmented) IP packet
|
| 672 |
|
|
from now on. */
|
| 673 |
|
|
BUF->ipoffset[ 0 ] = BUF->ipoffset[ 1 ] = 0;
|
| 674 |
|
|
BUF->len[ 0 ] = uip_reasslen >> 8;
|
| 675 |
|
|
BUF->len[ 1 ] = uip_reasslen & 0xff;
|
| 676 |
|
|
BUF->ipchksum = 0;
|
| 677 |
|
|
BUF->ipchksum = ~( uip_ipchksum() );
|
| 678 |
|
|
|
| 679 |
|
|
return uip_reasslen;
|
| 680 |
|
|
}
|
| 681 |
|
|
}
|
| 682 |
|
|
|
| 683 |
|
|
nullreturn:
|
| 684 |
|
|
|
| 685 |
|
|
return 0;
|
| 686 |
|
|
}
|
| 687 |
|
|
/*---------------------------------------------------------------------------*/
|
| 688 |
|
|
#endif /* UIP_REASSEMBLY */
|
| 689 |
|
|
|
| 690 |
|
|
|
| 691 |
|
|
static void uip_add_rcv_nxt( u16_t n )
|
| 692 |
|
|
{
|
| 693 |
|
|
uip_add32( uip_conn->rcv_nxt, n );
|
| 694 |
|
|
uip_conn->rcv_nxt[ 0 ] = uip_acc32[ 0 ];
|
| 695 |
|
|
uip_conn->rcv_nxt[ 1 ] = uip_acc32[ 1 ];
|
| 696 |
|
|
uip_conn->rcv_nxt[ 2 ] = uip_acc32[ 2 ];
|
| 697 |
|
|
uip_conn->rcv_nxt[ 3 ] = uip_acc32[ 3 ];
|
| 698 |
|
|
}
|
| 699 |
|
|
/*---------------------------------------------------------------------------*/
|
| 700 |
|
|
|
| 701 |
|
|
void uip_process( u8_t flag )
|
| 702 |
|
|
{
|
| 703 |
|
|
register struct uip_conn *uip_connr = uip_conn;
|
| 704 |
|
|
|
| 705 |
|
|
#if UIP_UDP
|
| 706 |
|
|
if( flag == UIP_UDP_SEND_CONN )
|
| 707 |
|
|
{
|
| 708 |
|
|
goto udp_send;
|
| 709 |
|
|
}
|
| 710 |
|
|
#endif /* UIP_UDP */
|
| 711 |
|
|
|
| 712 |
|
|
uip_sappdata = uip_appdata = &uip_buf[UIP_IPTCPH_LEN + UIP_LLH_LEN];
|
| 713 |
|
|
|
| 714 |
|
|
/* Check if we were invoked because of a poll request for a
|
| 715 |
|
|
particular connection. */
|
| 716 |
|
|
if( flag == UIP_POLL_REQUEST )
|
| 717 |
|
|
{
|
| 718 |
|
|
if( (uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED && !uip_outstanding(uip_connr) )
|
| 719 |
|
|
{
|
| 720 |
|
|
uip_flags = UIP_POLL;
|
| 721 |
|
|
UIP_APPCALL();
|
| 722 |
|
|
goto appsend;
|
| 723 |
|
|
}
|
| 724 |
|
|
|
| 725 |
|
|
goto drop;
|
| 726 |
|
|
|
| 727 |
|
|
/* Check if we were invoked because of the perodic timer fireing. */
|
| 728 |
|
|
}
|
| 729 |
|
|
else if( flag == UIP_TIMER )
|
| 730 |
|
|
{
|
| 731 |
|
|
#if UIP_REASSEMBLY
|
| 732 |
|
|
if( uip_reasstmr != 0 )
|
| 733 |
|
|
{
|
| 734 |
|
|
--uip_reasstmr;
|
| 735 |
|
|
}
|
| 736 |
|
|
#endif /* UIP_REASSEMBLY */
|
| 737 |
|
|
|
| 738 |
|
|
/* Increase the initial sequence number. */
|
| 739 |
|
|
if( ++iss[ 3 ] == 0 )
|
| 740 |
|
|
{
|
| 741 |
|
|
if( ++iss[ 2 ] == 0 )
|
| 742 |
|
|
{
|
| 743 |
|
|
if( ++iss[ 1 ] == 0 )
|
| 744 |
|
|
{
|
| 745 |
|
|
++iss[ 0 ];
|
| 746 |
|
|
}
|
| 747 |
|
|
}
|
| 748 |
|
|
}
|
| 749 |
|
|
|
| 750 |
|
|
/* Reset the length variables. */
|
| 751 |
|
|
uip_len = 0;
|
| 752 |
|
|
uip_slen = 0;
|
| 753 |
|
|
|
| 754 |
|
|
/* Check if the connection is in a state in which we simply wait
|
| 755 |
|
|
for the connection to time out. If so, we increase the
|
| 756 |
|
|
connection's timer and remove the connection if it times
|
| 757 |
|
|
out. */
|
| 758 |
|
|
if( uip_connr->tcpstateflags == UIP_TIME_WAIT || uip_connr->tcpstateflags == UIP_FIN_WAIT_2 )
|
| 759 |
|
|
{
|
| 760 |
|
|
++( uip_connr->timer );
|
| 761 |
|
|
if( uip_connr->timer == UIP_TIME_WAIT_TIMEOUT )
|
| 762 |
|
|
{
|
| 763 |
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
| 764 |
|
|
}
|
| 765 |
|
|
}
|
| 766 |
|
|
else if( uip_connr->tcpstateflags != UIP_CLOSED )
|
| 767 |
|
|
{
|
| 768 |
|
|
/* If the connection has outstanding data, we increase the
|
| 769 |
|
|
connection's timer and see if it has reached the RTO value
|
| 770 |
|
|
in which case we retransmit. */
|
| 771 |
|
|
if( uip_outstanding(uip_connr) )
|
| 772 |
|
|
{
|
| 773 |
|
|
if( uip_connr->timer-- == 0 )
|
| 774 |
|
|
{
|
| 775 |
|
|
if
|
| 776 |
|
|
(
|
| 777 |
|
|
uip_connr->nrtx == UIP_MAXRTX ||
|
| 778 |
|
|
(
|
| 779 |
|
|
(uip_connr->tcpstateflags == UIP_SYN_SENT || uip_connr->tcpstateflags == UIP_SYN_RCVD) &&
|
| 780 |
|
|
uip_connr->nrtx == UIP_MAXSYNRTX
|
| 781 |
|
|
)
|
| 782 |
|
|
)
|
| 783 |
|
|
{
|
| 784 |
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
| 785 |
|
|
|
| 786 |
|
|
/* We call UIP_APPCALL() with uip_flags set to
|
| 787 |
|
|
UIP_TIMEDOUT to inform the application that the
|
| 788 |
|
|
connection has timed out. */
|
| 789 |
|
|
uip_flags = UIP_TIMEDOUT;
|
| 790 |
|
|
UIP_APPCALL();
|
| 791 |
|
|
|
| 792 |
|
|
/* We also send a reset packet to the remote host. */
|
| 793 |
|
|
BUF->flags = TCP_RST | TCP_ACK;
|
| 794 |
|
|
goto tcp_send_nodata;
|
| 795 |
|
|
}
|
| 796 |
|
|
|
| 797 |
|
|
/* Exponential backoff. */
|
| 798 |
|
|
uip_connr->timer = UIP_RTO << ( uip_connr->nrtx > 4 ? 4 : uip_connr->nrtx );
|
| 799 |
|
|
++( uip_connr->nrtx );
|
| 800 |
|
|
|
| 801 |
|
|
/* Ok, so we need to retransmit. We do this differently
|
| 802 |
|
|
depending on which state we are in. In ESTABLISHED, we
|
| 803 |
|
|
call upon the application so that it may prepare the
|
| 804 |
|
|
data for the retransmit. In SYN_RCVD, we resend the
|
| 805 |
|
|
SYNACK that we sent earlier and in LAST_ACK we have to
|
| 806 |
|
|
retransmit our FINACK. */
|
| 807 |
|
|
UIP_STAT( ++uip_stat.tcp.rexmit );
|
| 808 |
|
|
switch( uip_connr->tcpstateflags & UIP_TS_MASK )
|
| 809 |
|
|
{
|
| 810 |
|
|
case UIP_SYN_RCVD:
|
| 811 |
|
|
/* In the SYN_RCVD state, we should retransmit our
|
| 812 |
|
|
SYNACK. */
|
| 813 |
|
|
goto tcp_send_synack;
|
| 814 |
|
|
|
| 815 |
|
|
#if UIP_ACTIVE_OPEN
|
| 816 |
|
|
case UIP_SYN_SENT:
|
| 817 |
|
|
/* In the SYN_SENT state, we retransmit out SYN. */
|
| 818 |
|
|
BUF->flags = 0;
|
| 819 |
|
|
goto tcp_send_syn;
|
| 820 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 821 |
|
|
|
| 822 |
|
|
case UIP_ESTABLISHED:
|
| 823 |
|
|
/* In the ESTABLISHED state, we call upon the application
|
| 824 |
|
|
to do the actual retransmit after which we jump into
|
| 825 |
|
|
the code for sending out the packet (the apprexmit
|
| 826 |
|
|
label). */
|
| 827 |
|
|
uip_flags = UIP_REXMIT;
|
| 828 |
|
|
UIP_APPCALL();
|
| 829 |
|
|
goto apprexmit;
|
| 830 |
|
|
|
| 831 |
|
|
case UIP_FIN_WAIT_1:
|
| 832 |
|
|
case UIP_CLOSING:
|
| 833 |
|
|
case UIP_LAST_ACK:
|
| 834 |
|
|
/* In all these states we should retransmit a FINACK. */
|
| 835 |
|
|
goto tcp_send_finack;
|
| 836 |
|
|
}
|
| 837 |
|
|
}
|
| 838 |
|
|
}
|
| 839 |
|
|
else if( (uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_ESTABLISHED )
|
| 840 |
|
|
{
|
| 841 |
|
|
/* If there was no need for a retransmission, we poll the
|
| 842 |
|
|
application for new data. */
|
| 843 |
|
|
uip_flags = UIP_POLL;
|
| 844 |
|
|
UIP_APPCALL();
|
| 845 |
|
|
goto appsend;
|
| 846 |
|
|
}
|
| 847 |
|
|
}
|
| 848 |
|
|
|
| 849 |
|
|
goto drop;
|
| 850 |
|
|
}
|
| 851 |
|
|
|
| 852 |
|
|
#if UIP_UDP
|
| 853 |
|
|
if( flag == UIP_UDP_TIMER )
|
| 854 |
|
|
{
|
| 855 |
|
|
if( uip_udp_conn->lport != 0 )
|
| 856 |
|
|
{
|
| 857 |
|
|
uip_conn = NULL;
|
| 858 |
|
|
uip_sappdata = uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN];
|
| 859 |
|
|
uip_len = uip_slen = 0;
|
| 860 |
|
|
uip_flags = UIP_POLL;
|
| 861 |
|
|
UIP_UDP_APPCALL();
|
| 862 |
|
|
goto udp_send;
|
| 863 |
|
|
}
|
| 864 |
|
|
else
|
| 865 |
|
|
{
|
| 866 |
|
|
goto drop;
|
| 867 |
|
|
}
|
| 868 |
|
|
}
|
| 869 |
|
|
#endif
|
| 870 |
|
|
|
| 871 |
|
|
/* This is where the input processing starts. */
|
| 872 |
|
|
UIP_STAT( ++uip_stat.ip.recv );
|
| 873 |
|
|
|
| 874 |
|
|
/* Start of IP input header processing code. */
|
| 875 |
|
|
#if UIP_CONF_IPV6
|
| 876 |
|
|
/* Check validity of the IP header. */
|
| 877 |
|
|
if( (BUF->vtc & 0xf0) != 0x60 )
|
| 878 |
|
|
{ /* IP version and header length. */
|
| 879 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 880 |
|
|
UIP_STAT( ++uip_stat.ip.vhlerr );
|
| 881 |
|
|
UIP_LOG( "ipv6: invalid version." );
|
| 882 |
|
|
goto drop;
|
| 883 |
|
|
}
|
| 884 |
|
|
|
| 885 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 886 |
|
|
/* Check validity of the IP header. */
|
| 887 |
|
|
if( BUF->vhl != 0x45 )
|
| 888 |
|
|
{ /* IP version and header length. */
|
| 889 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 890 |
|
|
UIP_STAT( ++uip_stat.ip.vhlerr );
|
| 891 |
|
|
UIP_LOG( "ip: invalid version or header length." );
|
| 892 |
|
|
goto drop;
|
| 893 |
|
|
}
|
| 894 |
|
|
|
| 895 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 896 |
|
|
|
| 897 |
|
|
/* Check the size of the packet. If the size reported to us in
|
| 898 |
|
|
uip_len is smaller the size reported in the IP header, we assume
|
| 899 |
|
|
that the packet has been corrupted in transit. If the size of
|
| 900 |
|
|
uip_len is larger than the size reported in the IP packet header,
|
| 901 |
|
|
the packet has been padded and we set uip_len to the correct
|
| 902 |
|
|
value.. */
|
| 903 |
|
|
if( (BUF->len[ 0 ] << 8) + BUF->len[ 1 ] <= uip_len )
|
| 904 |
|
|
{
|
| 905 |
|
|
uip_len = ( BUF->len[ 0 ] << 8 ) + BUF->len[ 1 ];
|
| 906 |
|
|
#if UIP_CONF_IPV6
|
| 907 |
|
|
/* The length reported in the IPv6 header is the
|
| 908 |
|
|
length of the payload that follows the
|
| 909 |
|
|
header. However, uIP uses the uip_len variable
|
| 910 |
|
|
for holding the size of the entire packet,
|
| 911 |
|
|
including the IP header. For IPv4 this is not a
|
| 912 |
|
|
problem as the length field in the IPv4 header
|
| 913 |
|
|
contains the length of the entire packet. But
|
| 914 |
|
|
for IPv6 we need to add the size of the IPv6
|
| 915 |
|
|
header (40 bytes). */
|
| 916 |
|
|
uip_len += 40;
|
| 917 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 918 |
|
|
}
|
| 919 |
|
|
else
|
| 920 |
|
|
{
|
| 921 |
|
|
UIP_LOG( "ip: packet shorter than reported in IP header." );
|
| 922 |
|
|
goto drop;
|
| 923 |
|
|
}
|
| 924 |
|
|
|
| 925 |
|
|
#if !UIP_CONF_IPV6
|
| 926 |
|
|
/* Check the fragment flag. */
|
| 927 |
|
|
if( (BUF->ipoffset[ 0 ] & 0x3f) != 0 || BUF->ipoffset[ 1 ] != 0 )
|
| 928 |
|
|
{
|
| 929 |
|
|
#if UIP_REASSEMBLY
|
| 930 |
|
|
uip_len = uip_reass();
|
| 931 |
|
|
if( uip_len == 0 )
|
| 932 |
|
|
{
|
| 933 |
|
|
goto drop;
|
| 934 |
|
|
}
|
| 935 |
|
|
#else /* UIP_REASSEMBLY */
|
| 936 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 937 |
|
|
UIP_STAT( ++uip_stat.ip.fragerr );
|
| 938 |
|
|
UIP_LOG( "ip: fragment dropped." );
|
| 939 |
|
|
goto drop;
|
| 940 |
|
|
#endif /* UIP_REASSEMBLY */
|
| 941 |
|
|
}
|
| 942 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 943 |
|
|
|
| 944 |
|
|
if( uip_ipaddr_cmp(&uip_hostaddr, &uip_all_zeroes_addr) )
|
| 945 |
|
|
{
|
| 946 |
|
|
/* If we are configured to use ping IP address configuration and
|
| 947 |
|
|
hasn't been assigned an IP address yet, we accept all ICMP
|
| 948 |
|
|
packets. */
|
| 949 |
|
|
#if UIP_PINGADDRCONF && !UIP_CONF_IPV6
|
| 950 |
|
|
if( BUF->proto == UIP_PROTO_ICMP )
|
| 951 |
|
|
{
|
| 952 |
|
|
UIP_LOG( "ip: possible ping config packet received." );
|
| 953 |
|
|
goto icmp_input;
|
| 954 |
|
|
}
|
| 955 |
|
|
else
|
| 956 |
|
|
{
|
| 957 |
|
|
UIP_LOG( "ip: packet dropped since no address assigned." );
|
| 958 |
|
|
goto drop;
|
| 959 |
|
|
}
|
| 960 |
|
|
#endif /* UIP_PINGADDRCONF */
|
| 961 |
|
|
}
|
| 962 |
|
|
else
|
| 963 |
|
|
{
|
| 964 |
|
|
/* If IP broadcast support is configured, we check for a broadcast
|
| 965 |
|
|
UDP packet, which may be destined to us. */
|
| 966 |
|
|
#if UIP_BROADCAST
|
| 967 |
|
|
//DEBUG_PRINTF( "UDP IP checksum 0x%04x\n", uip_ipchksum() );
|
| 968 |
|
|
if( BUF->proto == UIP_PROTO_UDP && uip_ipaddr_cmp(&BUF->destipaddr, &uip_broadcast_addr) /*&& uip_ipchksum() == 0xffff*/ )
|
| 969 |
|
|
{
|
| 970 |
|
|
goto udp_input;
|
| 971 |
|
|
}
|
| 972 |
|
|
#endif /* UIP_BROADCAST */
|
| 973 |
|
|
|
| 974 |
|
|
/* Check if the packet is destined for our IP address. */
|
| 975 |
|
|
#if !UIP_CONF_IPV6
|
| 976 |
|
|
if( !uip_ipaddr_cmp(&BUF->destipaddr, &uip_hostaddr) )
|
| 977 |
|
|
{
|
| 978 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 979 |
|
|
goto drop;
|
| 980 |
|
|
}
|
| 981 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 982 |
|
|
/* For IPv6, packet reception is a little trickier as we need to
|
| 983 |
|
|
make sure that we listen to certain multicast addresses (all
|
| 984 |
|
|
hosts multicast address, and the solicited-node multicast
|
| 985 |
|
|
address) as well. However, we will cheat here and accept all
|
| 986 |
|
|
multicast packets that are sent to the ff02::/16 addresses. */
|
| 987 |
|
|
if( !uip_ipaddr_cmp(&BUF->destipaddr, &uip_hostaddr) && BUF->destipaddr.u16[ 0 ] != HTONS(0xff02) )
|
| 988 |
|
|
{
|
| 989 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 990 |
|
|
goto drop;
|
| 991 |
|
|
}
|
| 992 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 993 |
|
|
}
|
| 994 |
|
|
|
| 995 |
|
|
#if !UIP_CONF_IPV6
|
| 996 |
|
|
if( uip_ipchksum() != 0xffff )
|
| 997 |
|
|
{
|
| 998 |
|
|
/* Compute and check the IP header checksum. */
|
| 999 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 1000 |
|
|
UIP_STAT( ++uip_stat.ip.chkerr );
|
| 1001 |
|
|
UIP_LOG( "ip: bad checksum." );
|
| 1002 |
|
|
goto drop;
|
| 1003 |
|
|
}
|
| 1004 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 1005 |
|
|
|
| 1006 |
|
|
if( BUF->proto == UIP_PROTO_TCP )
|
| 1007 |
|
|
{
|
| 1008 |
|
|
/* Check for TCP packet. If so, proceed with TCP input processing. */
|
| 1009 |
|
|
goto tcp_input;
|
| 1010 |
|
|
}
|
| 1011 |
|
|
|
| 1012 |
|
|
#if UIP_UDP
|
| 1013 |
|
|
if( BUF->proto == UIP_PROTO_UDP )
|
| 1014 |
|
|
{
|
| 1015 |
|
|
goto udp_input;
|
| 1016 |
|
|
}
|
| 1017 |
|
|
#endif /* UIP_UDP */
|
| 1018 |
|
|
|
| 1019 |
|
|
#if !UIP_CONF_IPV6
|
| 1020 |
|
|
/* ICMPv4 processing code follows. */
|
| 1021 |
|
|
if( BUF->proto != UIP_PROTO_ICMP )
|
| 1022 |
|
|
{
|
| 1023 |
|
|
/* We only allow ICMP packets from here. */
|
| 1024 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 1025 |
|
|
UIP_STAT( ++uip_stat.ip.protoerr );
|
| 1026 |
|
|
UIP_LOG( "ip: neither tcp nor icmp." );
|
| 1027 |
|
|
goto drop;
|
| 1028 |
|
|
}
|
| 1029 |
|
|
|
| 1030 |
|
|
#if UIP_PINGADDRCONF
|
| 1031 |
|
|
icmp_input :
|
| 1032 |
|
|
#endif /* UIP_PINGADDRCONF */
|
| 1033 |
|
|
|
| 1034 |
|
|
UIP_STAT( ++uip_stat.icmp.recv );
|
| 1035 |
|
|
|
| 1036 |
|
|
/* ICMP echo (i.e., ping) processing. This is simple, we only change
|
| 1037 |
|
|
the ICMP type from ECHO to ECHO_REPLY and adjust the ICMP
|
| 1038 |
|
|
checksum before we return the packet. */
|
| 1039 |
|
|
if( ICMPBUF->type != ICMP_ECHO )
|
| 1040 |
|
|
{
|
| 1041 |
|
|
UIP_STAT( ++uip_stat.icmp.drop );
|
| 1042 |
|
|
UIP_STAT( ++uip_stat.icmp.typeerr );
|
| 1043 |
|
|
UIP_LOG( "icmp: not icmp echo." );
|
| 1044 |
|
|
goto drop;
|
| 1045 |
|
|
}
|
| 1046 |
|
|
|
| 1047 |
|
|
/* If we are configured to use ping IP address assignment, we use
|
| 1048 |
|
|
the destination IP address of this ping packet and assign it to
|
| 1049 |
|
|
ourself. */
|
| 1050 |
|
|
#if UIP_PINGADDRCONF
|
| 1051 |
|
|
if( uip_ipaddr_cmp(&uip_hostaddr, &uip_all_zeroes_addr) )
|
| 1052 |
|
|
{
|
| 1053 |
|
|
uip_hostaddr = BUF->destipaddr;
|
| 1054 |
|
|
}
|
| 1055 |
|
|
#endif /* UIP_PINGADDRCONF */
|
| 1056 |
|
|
|
| 1057 |
|
|
ICMPBUF->type = ICMP_ECHO_REPLY;
|
| 1058 |
|
|
|
| 1059 |
|
|
if( ICMPBUF->icmpchksum >= HTONS(0xffff - (ICMP_ECHO << 8)) )
|
| 1060 |
|
|
{
|
| 1061 |
|
|
ICMPBUF->icmpchksum += HTONS( ICMP_ECHO << 8 ) + 1;
|
| 1062 |
|
|
}
|
| 1063 |
|
|
else
|
| 1064 |
|
|
{
|
| 1065 |
|
|
ICMPBUF->icmpchksum += HTONS( ICMP_ECHO << 8 );
|
| 1066 |
|
|
}
|
| 1067 |
|
|
|
| 1068 |
|
|
/* Swap IP addresses. */
|
| 1069 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &BUF->srcipaddr );
|
| 1070 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 1071 |
|
|
|
| 1072 |
|
|
UIP_STAT( ++uip_stat.icmp.sent );
|
| 1073 |
|
|
BUF->ttl = UIP_TTL;
|
| 1074 |
|
|
goto ip_send_nolen;
|
| 1075 |
|
|
|
| 1076 |
|
|
/* End of IPv4 input header processing code. */
|
| 1077 |
|
|
|
| 1078 |
|
|
#else /* !UIP_CONF_IPV6 */
|
| 1079 |
|
|
|
| 1080 |
|
|
/* This is IPv6 ICMPv6 processing code. */
|
| 1081 |
|
|
|
| 1082 |
|
|
//DEBUG_PRINTF( "icmp6_input: length %d\n", uip_len );
|
| 1083 |
|
|
if( BUF->proto != UIP_PROTO_ICMP6 )
|
| 1084 |
|
|
{
|
| 1085 |
|
|
/* We only allow ICMPv6 packets from here. */
|
| 1086 |
|
|
UIP_STAT( ++uip_stat.ip.drop );
|
| 1087 |
|
|
UIP_STAT( ++uip_stat.ip.protoerr );
|
| 1088 |
|
|
UIP_LOG( "ip: neither tcp nor icmp6." );
|
| 1089 |
|
|
goto drop;
|
| 1090 |
|
|
}
|
| 1091 |
|
|
|
| 1092 |
|
|
UIP_STAT( ++uip_stat.icmp.recv );
|
| 1093 |
|
|
|
| 1094 |
|
|
/* If we get a neighbor solicitation for our address we should send
|
| 1095 |
|
|
a neighbor advertisement message back. */
|
| 1096 |
|
|
if( ICMPBUF->type == ICMP6_NEIGHBOR_SOLICITATION )
|
| 1097 |
|
|
{
|
| 1098 |
|
|
if( uip_ipaddr_cmp(&ICMPBUF->icmp6data, &uip_hostaddr) )
|
| 1099 |
|
|
{
|
| 1100 |
|
|
if( ICMPBUF->options[ 0 ] == ICMP6_OPTION_SOURCE_LINK_ADDRESS )
|
| 1101 |
|
|
{
|
| 1102 |
|
|
/* Save the sender's address in our neighbor list. */
|
| 1103 |
|
|
uip_neighbor_add( &ICMPBUF->srcipaddr, &(ICMPBUF->options[ 2 ]) );
|
| 1104 |
|
|
}
|
| 1105 |
|
|
|
| 1106 |
|
|
/* We should now send a neighbor advertisement back to where the
|
| 1107 |
|
|
neighbor solicication came from. */
|
| 1108 |
|
|
ICMPBUF->type = ICMP6_NEIGHBOR_ADVERTISEMENT;
|
| 1109 |
|
|
ICMPBUF->flags = ICMP6_FLAG_S; /* Solicited flag. */
|
| 1110 |
|
|
|
| 1111 |
|
|
ICMPBUF->reserved1 = ICMPBUF->reserved2 = ICMPBUF->reserved3 = 0;
|
| 1112 |
|
|
|
| 1113 |
|
|
uip_ipaddr_copy( &ICMPBUF->destipaddr, &ICMPBUF->srcipaddr );
|
| 1114 |
|
|
uip_ipaddr_copy( &ICMPBUF->srcipaddr, &uip_hostaddr );
|
| 1115 |
|
|
ICMPBUF->options[ 0 ] = ICMP6_OPTION_TARGET_LINK_ADDRESS;
|
| 1116 |
|
|
ICMPBUF->options[ 1 ] = 1; /* Options length, 1 = 8 bytes. */
|
| 1117 |
|
|
memcpy( &(ICMPBUF->options[ 2 ]), &uip_ethaddr, sizeof(uip_ethaddr) );
|
| 1118 |
|
|
ICMPBUF->icmpchksum = 0;
|
| 1119 |
|
|
ICMPBUF->icmpchksum = ~uip_icmp6chksum();
|
| 1120 |
|
|
|
| 1121 |
|
|
goto send;
|
| 1122 |
|
|
}
|
| 1123 |
|
|
|
| 1124 |
|
|
goto drop;
|
| 1125 |
|
|
}
|
| 1126 |
|
|
else if( ICMPBUF->type == ICMP6_ECHO )
|
| 1127 |
|
|
{
|
| 1128 |
|
|
/* ICMP echo (i.e., ping) processing. This is simple, we only
|
| 1129 |
|
|
change the ICMP type from ECHO to ECHO_REPLY and update the
|
| 1130 |
|
|
ICMP checksum before we return the packet. */
|
| 1131 |
|
|
ICMPBUF->type = ICMP6_ECHO_REPLY;
|
| 1132 |
|
|
|
| 1133 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &BUF->srcipaddr );
|
| 1134 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 1135 |
|
|
ICMPBUF->icmpchksum = 0;
|
| 1136 |
|
|
ICMPBUF->icmpchksum = ~uip_icmp6chksum();
|
| 1137 |
|
|
|
| 1138 |
|
|
UIP_STAT( ++uip_stat.icmp.sent );
|
| 1139 |
|
|
goto send;
|
| 1140 |
|
|
}
|
| 1141 |
|
|
else
|
| 1142 |
|
|
{
|
| 1143 |
|
|
//DEBUG_PRINTF( "Unknown icmp6 message type %d\n", ICMPBUF->type );
|
| 1144 |
|
|
UIP_STAT( ++uip_stat.icmp.drop );
|
| 1145 |
|
|
UIP_STAT( ++uip_stat.icmp.typeerr );
|
| 1146 |
|
|
UIP_LOG( "icmp: unknown ICMP message." );
|
| 1147 |
|
|
goto drop;
|
| 1148 |
|
|
}
|
| 1149 |
|
|
|
| 1150 |
|
|
/* End of IPv6 ICMP processing. */
|
| 1151 |
|
|
#endif /* !UIP_CONF_IPV6 */
|
| 1152 |
|
|
|
| 1153 |
|
|
#if UIP_UDP
|
| 1154 |
|
|
/* UDP input processing. */
|
| 1155 |
|
|
udp_input :
|
| 1156 |
|
|
/* UDP processing is really just a hack. We don't do anything to the
|
| 1157 |
|
|
UDP/IP headers, but let the UDP application do all the hard
|
| 1158 |
|
|
work. If the application sets uip_slen, it has a packet to
|
| 1159 |
|
|
send. */
|
| 1160 |
|
|
#if UIP_UDP_CHECKSUMS
|
| 1161 |
|
|
uip_len = uip_len - UIP_IPUDPH_LEN;
|
| 1162 |
|
|
uip_appdata = &uip_buf[ UIP_LLH_LEN + UIP_IPUDPH_LEN ];
|
| 1163 |
|
|
if( UDPBUF->udpchksum != 0 && uip_udpchksum() != 0xffff )
|
| 1164 |
|
|
{
|
| 1165 |
|
|
UIP_STAT( ++uip_stat.udp.drop );
|
| 1166 |
|
|
UIP_STAT( ++uip_stat.udp.chkerr );
|
| 1167 |
|
|
UIP_LOG( "udp: bad checksum." );
|
| 1168 |
|
|
goto drop;
|
| 1169 |
|
|
}
|
| 1170 |
|
|
|
| 1171 |
|
|
#else /* UIP_UDP_CHECKSUMS */
|
| 1172 |
|
|
uip_len = uip_len - UIP_IPUDPH_LEN;
|
| 1173 |
|
|
#endif /* UIP_UDP_CHECKSUMS */
|
| 1174 |
|
|
|
| 1175 |
|
|
/* Demultiplex this UDP packet between the UDP "connections". */
|
| 1176 |
|
|
for( uip_udp_conn = &uip_udp_conns[ 0 ]; uip_udp_conn < &uip_udp_conns[UIP_UDP_CONNS]; ++uip_udp_conn )
|
| 1177 |
|
|
{
|
| 1178 |
|
|
/* If the local UDP port is non-zero, the connection is considered
|
| 1179 |
|
|
to be used. If so, the local port number is checked against the
|
| 1180 |
|
|
destination port number in the received packet. If the two port
|
| 1181 |
|
|
numbers match, the remote port number is checked if the
|
| 1182 |
|
|
connection is bound to a remote port. Finally, if the
|
| 1183 |
|
|
connection is bound to a remote IP address, the source IP
|
| 1184 |
|
|
address of the packet is checked. */
|
| 1185 |
|
|
if
|
| 1186 |
|
|
(
|
| 1187 |
|
|
uip_udp_conn->lport != 0 &&
|
| 1188 |
|
|
UDPBUF->destport == uip_udp_conn->lport &&
|
| 1189 |
|
|
(uip_udp_conn->rport == 0 || UDPBUF->srcport == uip_udp_conn->rport) &&
|
| 1190 |
|
|
(
|
| 1191 |
|
|
uip_ipaddr_cmp(&uip_udp_conn->ripaddr, &uip_all_zeroes_addr) ||
|
| 1192 |
|
|
uip_ipaddr_cmp(&uip_udp_conn->ripaddr, &uip_broadcast_addr) ||
|
| 1193 |
|
|
uip_ipaddr_cmp(&BUF->srcipaddr, &uip_udp_conn->ripaddr)
|
| 1194 |
|
|
)
|
| 1195 |
|
|
)
|
| 1196 |
|
|
{
|
| 1197 |
|
|
goto udp_found;
|
| 1198 |
|
|
}
|
| 1199 |
|
|
}
|
| 1200 |
|
|
|
| 1201 |
|
|
UIP_LOG( "udp: no matching connection found" );
|
| 1202 |
|
|
|
| 1203 |
|
|
#if UIP_CONF_ICMP_DEST_UNREACH && !UIP_CONF_IPV6
|
| 1204 |
|
|
|
| 1205 |
|
|
/* Copy fields from packet header into payload of this ICMP packet. */
|
| 1206 |
|
|
memcpy( &(ICMPBUF->payload[ 0 ]), ICMPBUF, UIP_IPH_LEN + 8 );
|
| 1207 |
|
|
|
| 1208 |
|
|
/* Set the ICMP type and code. */
|
| 1209 |
|
|
ICMPBUF->type = ICMP_DEST_UNREACHABLE;
|
| 1210 |
|
|
ICMPBUF->icode = ICMP_PORT_UNREACHABLE;
|
| 1211 |
|
|
|
| 1212 |
|
|
/* Calculate the ICMP checksum. */
|
| 1213 |
|
|
ICMPBUF->icmpchksum = 0;
|
| 1214 |
|
|
ICMPBUF->icmpchksum = ~uip_chksum( ( u16_t * ) &(ICMPBUF->type), 36 );
|
| 1215 |
|
|
|
| 1216 |
|
|
/* Set the IP destination address to be the source address of the
|
| 1217 |
|
|
original packet. */
|
| 1218 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &BUF->srcipaddr );
|
| 1219 |
|
|
|
| 1220 |
|
|
/* Set our IP address as the source address. */
|
| 1221 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 1222 |
|
|
|
| 1223 |
|
|
/* The size of the ICMP destination unreachable packet is 36 + the
|
| 1224 |
|
|
size of the IP header (20) = 56. */
|
| 1225 |
|
|
uip_len = 36 + UIP_IPH_LEN;
|
| 1226 |
|
|
ICMPBUF->len[ 0 ] = 0;
|
| 1227 |
|
|
ICMPBUF->len[ 1 ] = ( u8_t ) uip_len;
|
| 1228 |
|
|
ICMPBUF->ttl = UIP_TTL;
|
| 1229 |
|
|
ICMPBUF->proto = UIP_PROTO_ICMP;
|
| 1230 |
|
|
|
| 1231 |
|
|
goto ip_send_nolen;
|
| 1232 |
|
|
#else /* UIP_CONF_ICMP_DEST_UNREACH */
|
| 1233 |
|
|
goto drop;
|
| 1234 |
|
|
#endif /* UIP_CONF_ICMP_DEST_UNREACH */
|
| 1235 |
|
|
|
| 1236 |
|
|
udp_found : uip_conn = NULL;
|
| 1237 |
|
|
uip_flags = UIP_NEWDATA;
|
| 1238 |
|
|
uip_sappdata = uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN];
|
| 1239 |
|
|
uip_slen = 0;
|
| 1240 |
|
|
UIP_UDP_APPCALL();
|
| 1241 |
|
|
|
| 1242 |
|
|
udp_send:
|
| 1243 |
|
|
if( uip_slen == 0 )
|
| 1244 |
|
|
{
|
| 1245 |
|
|
goto drop;
|
| 1246 |
|
|
}
|
| 1247 |
|
|
|
| 1248 |
|
|
uip_len = uip_slen + UIP_IPUDPH_LEN;
|
| 1249 |
|
|
|
| 1250 |
|
|
#if UIP_CONF_IPV6
|
| 1251 |
|
|
/* For IPv6, the IP length field does not include the IPv6 IP header
|
| 1252 |
|
|
length. */
|
| 1253 |
|
|
BUF->len[ 0 ] = ( (uip_len - UIP_IPH_LEN) >> 8 );
|
| 1254 |
|
|
BUF->len[ 1 ] = ( (uip_len - UIP_IPH_LEN) & 0xff );
|
| 1255 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 1256 |
|
|
BUF->len[ 0 ] = ( uip_len >> 8 );
|
| 1257 |
|
|
BUF->len[ 1 ] = ( uip_len & 0xff );
|
| 1258 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 1259 |
|
|
|
| 1260 |
|
|
BUF->ttl = uip_udp_conn->ttl;
|
| 1261 |
|
|
BUF->proto = UIP_PROTO_UDP;
|
| 1262 |
|
|
|
| 1263 |
|
|
UDPBUF->udplen = HTONS( uip_slen + UIP_UDPH_LEN );
|
| 1264 |
|
|
UDPBUF->udpchksum = 0;
|
| 1265 |
|
|
|
| 1266 |
|
|
BUF->srcport = uip_udp_conn->lport;
|
| 1267 |
|
|
BUF->destport = uip_udp_conn->rport;
|
| 1268 |
|
|
|
| 1269 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 1270 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &uip_udp_conn->ripaddr );
|
| 1271 |
|
|
|
| 1272 |
|
|
uip_appdata = &uip_buf[UIP_LLH_LEN + UIP_IPTCPH_LEN];
|
| 1273 |
|
|
|
| 1274 |
|
|
#if UIP_UDP_CHECKSUMS
|
| 1275 |
|
|
/* Calculate UDP checksum. */
|
| 1276 |
|
|
UDPBUF->udpchksum = ~( uip_udpchksum() );
|
| 1277 |
|
|
if( UDPBUF->udpchksum == 0 )
|
| 1278 |
|
|
{
|
| 1279 |
|
|
UDPBUF->udpchksum = 0xffff;
|
| 1280 |
|
|
}
|
| 1281 |
|
|
#endif /* UIP_UDP_CHECKSUMS */
|
| 1282 |
|
|
goto ip_send_nolen;
|
| 1283 |
|
|
#endif /* UIP_UDP */
|
| 1284 |
|
|
|
| 1285 |
|
|
/* TCP input processing. */
|
| 1286 |
|
|
tcp_input : UIP_STAT( ++uip_stat.tcp.recv );
|
| 1287 |
|
|
|
| 1288 |
|
|
/* Start of TCP input header processing code. */
|
| 1289 |
|
|
if( uip_tcpchksum() != 0xffff )
|
| 1290 |
|
|
{
|
| 1291 |
|
|
/* Compute and check the TCP checksum. */
|
| 1292 |
|
|
UIP_STAT( ++uip_stat.tcp.drop );
|
| 1293 |
|
|
UIP_STAT( ++uip_stat.tcp.chkerr );
|
| 1294 |
|
|
UIP_LOG( "tcp: bad checksum." );
|
| 1295 |
|
|
goto drop;
|
| 1296 |
|
|
}
|
| 1297 |
|
|
|
| 1298 |
|
|
/* Demultiplex this segment. */
|
| 1299 |
|
|
|
| 1300 |
|
|
/* First check any active connections. */
|
| 1301 |
|
|
for( uip_connr = &uip_conns[ 0 ]; uip_connr <= &uip_conns[UIP_CONNS - 1]; ++uip_connr )
|
| 1302 |
|
|
{
|
| 1303 |
|
|
if
|
| 1304 |
|
|
(
|
| 1305 |
|
|
uip_connr->tcpstateflags != UIP_CLOSED &&
|
| 1306 |
|
|
BUF->destport == uip_connr->lport &&
|
| 1307 |
|
|
BUF->srcport == uip_connr->rport &&
|
| 1308 |
|
|
uip_ipaddr_cmp(&BUF->srcipaddr, &uip_connr->ripaddr)
|
| 1309 |
|
|
)
|
| 1310 |
|
|
{
|
| 1311 |
|
|
goto found;
|
| 1312 |
|
|
}
|
| 1313 |
|
|
}
|
| 1314 |
|
|
|
| 1315 |
|
|
/* If we didn't find and active connection that expected the packet,
|
| 1316 |
|
|
either this packet is an old duplicate, or this is a SYN packet
|
| 1317 |
|
|
destined for a connection in LISTEN. If the SYN flag isn't set,
|
| 1318 |
|
|
it is an old packet and we send a RST. */
|
| 1319 |
|
|
if( (BUF->flags & TCP_CTL) != TCP_SYN )
|
| 1320 |
|
|
{
|
| 1321 |
|
|
goto reset;
|
| 1322 |
|
|
}
|
| 1323 |
|
|
|
| 1324 |
|
|
tmp16 = BUF->destport;
|
| 1325 |
|
|
|
| 1326 |
|
|
/* Next, check listening connections. */
|
| 1327 |
|
|
for( c = 0; c < UIP_LISTENPORTS; ++c )
|
| 1328 |
|
|
{
|
| 1329 |
|
|
if( tmp16 == uip_listenports[ c ] )
|
| 1330 |
|
|
{
|
| 1331 |
|
|
goto found_listen;
|
| 1332 |
|
|
}
|
| 1333 |
|
|
}
|
| 1334 |
|
|
|
| 1335 |
|
|
/* No matching connection found, so we send a RST packet. */
|
| 1336 |
|
|
UIP_STAT( ++uip_stat.tcp.synrst );
|
| 1337 |
|
|
|
| 1338 |
|
|
reset:
|
| 1339 |
|
|
/* We do not send resets in response to resets. */
|
| 1340 |
|
|
if( BUF->flags & TCP_RST )
|
| 1341 |
|
|
{
|
| 1342 |
|
|
goto drop;
|
| 1343 |
|
|
}
|
| 1344 |
|
|
|
| 1345 |
|
|
UIP_STAT( ++uip_stat.tcp.rst );
|
| 1346 |
|
|
|
| 1347 |
|
|
BUF->flags = TCP_RST | TCP_ACK;
|
| 1348 |
|
|
uip_len = UIP_IPTCPH_LEN;
|
| 1349 |
|
|
BUF->tcpoffset = 5 << 4;
|
| 1350 |
|
|
|
| 1351 |
|
|
/* Flip the seqno and ackno fields in the TCP header. */
|
| 1352 |
|
|
c = BUF->seqno[ 3 ];
|
| 1353 |
|
|
BUF->seqno[ 3 ] = BUF->ackno[ 3 ];
|
| 1354 |
|
|
BUF->ackno[ 3 ] = c;
|
| 1355 |
|
|
|
| 1356 |
|
|
c = BUF->seqno[ 2 ];
|
| 1357 |
|
|
BUF->seqno[ 2 ] = BUF->ackno[ 2 ];
|
| 1358 |
|
|
BUF->ackno[ 2 ] = c;
|
| 1359 |
|
|
|
| 1360 |
|
|
c = BUF->seqno[ 1 ];
|
| 1361 |
|
|
BUF->seqno[ 1 ] = BUF->ackno[ 1 ];
|
| 1362 |
|
|
BUF->ackno[ 1 ] = c;
|
| 1363 |
|
|
|
| 1364 |
|
|
c = BUF->seqno[ 0 ];
|
| 1365 |
|
|
BUF->seqno[ 0 ] = BUF->ackno[ 0 ];
|
| 1366 |
|
|
BUF->ackno[ 0 ] = c;
|
| 1367 |
|
|
|
| 1368 |
|
|
/* We also have to increase the sequence number we are
|
| 1369 |
|
|
acknowledging. If the least significant byte overflowed, we need
|
| 1370 |
|
|
to propagate the carry to the other bytes as well. */
|
| 1371 |
|
|
if( ++BUF->ackno[ 3 ] == 0 )
|
| 1372 |
|
|
{
|
| 1373 |
|
|
if( ++BUF->ackno[ 2 ] == 0 )
|
| 1374 |
|
|
{
|
| 1375 |
|
|
if( ++BUF->ackno[ 1 ] == 0 )
|
| 1376 |
|
|
{
|
| 1377 |
|
|
++BUF->ackno[ 0 ];
|
| 1378 |
|
|
}
|
| 1379 |
|
|
}
|
| 1380 |
|
|
}
|
| 1381 |
|
|
|
| 1382 |
|
|
/* Swap port numbers. */
|
| 1383 |
|
|
tmp16 = BUF->srcport;
|
| 1384 |
|
|
BUF->srcport = BUF->destport;
|
| 1385 |
|
|
BUF->destport = tmp16;
|
| 1386 |
|
|
|
| 1387 |
|
|
/* Swap IP addresses. */
|
| 1388 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &BUF->srcipaddr );
|
| 1389 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 1390 |
|
|
|
| 1391 |
|
|
/* And send out the RST packet! */
|
| 1392 |
|
|
goto tcp_send_noconn;
|
| 1393 |
|
|
|
| 1394 |
|
|
/* This label will be jumped to if we matched the incoming packet
|
| 1395 |
|
|
with a connection in LISTEN. In that case, we should create a new
|
| 1396 |
|
|
connection and send a SYNACK in return. */
|
| 1397 |
|
|
found_listen:
|
| 1398 |
|
|
/* First we check if there are any connections avaliable. Unused
|
| 1399 |
|
|
connections are kept in the same table as used connections, but
|
| 1400 |
|
|
unused ones have the tcpstate set to CLOSED. Also, connections in
|
| 1401 |
|
|
TIME_WAIT are kept track of and we'll use the oldest one if no
|
| 1402 |
|
|
CLOSED connections are found. Thanks to Eddie C. Dost for a very
|
| 1403 |
|
|
nice algorithm for the TIME_WAIT search. */
|
| 1404 |
|
|
uip_connr = 0;
|
| 1405 |
|
|
for( c = 0; c < UIP_CONNS; ++c )
|
| 1406 |
|
|
{
|
| 1407 |
|
|
if( uip_conns[ c ].tcpstateflags == UIP_CLOSED )
|
| 1408 |
|
|
{
|
| 1409 |
|
|
uip_connr = &uip_conns[ c ];
|
| 1410 |
|
|
break;
|
| 1411 |
|
|
}
|
| 1412 |
|
|
|
| 1413 |
|
|
if( uip_conns[ c ].tcpstateflags == UIP_TIME_WAIT )
|
| 1414 |
|
|
{
|
| 1415 |
|
|
if( uip_connr == 0 || uip_conns[ c ].timer > uip_connr->timer )
|
| 1416 |
|
|
{
|
| 1417 |
|
|
uip_connr = &uip_conns[ c ];
|
| 1418 |
|
|
}
|
| 1419 |
|
|
}
|
| 1420 |
|
|
}
|
| 1421 |
|
|
|
| 1422 |
|
|
if( uip_connr == 0 )
|
| 1423 |
|
|
{
|
| 1424 |
|
|
/* All connections are used already, we drop packet and hope that
|
| 1425 |
|
|
the remote end will retransmit the packet at a time when we
|
| 1426 |
|
|
have more spare connections. */
|
| 1427 |
|
|
UIP_STAT( ++uip_stat.tcp.syndrop );
|
| 1428 |
|
|
UIP_LOG( "tcp: found no unused connections." );
|
| 1429 |
|
|
goto drop;
|
| 1430 |
|
|
}
|
| 1431 |
|
|
|
| 1432 |
|
|
uip_conn = uip_connr;
|
| 1433 |
|
|
|
| 1434 |
|
|
/* Fill in the necessary fields for the new connection. */
|
| 1435 |
|
|
uip_connr->rto = uip_connr->timer = UIP_RTO;
|
| 1436 |
|
|
uip_connr->sa = 0;
|
| 1437 |
|
|
uip_connr->sv = 4;
|
| 1438 |
|
|
uip_connr->nrtx = 0;
|
| 1439 |
|
|
uip_connr->lport = BUF->destport;
|
| 1440 |
|
|
uip_connr->rport = BUF->srcport;
|
| 1441 |
|
|
uip_ipaddr_copy( &uip_connr->ripaddr, &BUF->srcipaddr );
|
| 1442 |
|
|
uip_connr->tcpstateflags = UIP_SYN_RCVD;
|
| 1443 |
|
|
|
| 1444 |
|
|
uip_connr->snd_nxt[ 0 ] = iss[ 0 ];
|
| 1445 |
|
|
uip_connr->snd_nxt[ 1 ] = iss[ 1 ];
|
| 1446 |
|
|
uip_connr->snd_nxt[ 2 ] = iss[ 2 ];
|
| 1447 |
|
|
uip_connr->snd_nxt[ 3 ] = iss[ 3 ];
|
| 1448 |
|
|
uip_connr->len = 1;
|
| 1449 |
|
|
|
| 1450 |
|
|
/* rcv_nxt should be the seqno from the incoming packet + 1. */
|
| 1451 |
|
|
uip_connr->rcv_nxt[ 3 ] = BUF->seqno[ 3 ];
|
| 1452 |
|
|
uip_connr->rcv_nxt[ 2 ] = BUF->seqno[ 2 ];
|
| 1453 |
|
|
uip_connr->rcv_nxt[ 1 ] = BUF->seqno[ 1 ];
|
| 1454 |
|
|
uip_connr->rcv_nxt[ 0 ] = BUF->seqno[ 0 ];
|
| 1455 |
|
|
uip_add_rcv_nxt( 1 );
|
| 1456 |
|
|
|
| 1457 |
|
|
/* Parse the TCP MSS option, if present. */
|
| 1458 |
|
|
if( (BUF->tcpoffset & 0xf0) > 0x50 )
|
| 1459 |
|
|
{
|
| 1460 |
|
|
for( c = 0; c < ((BUF->tcpoffset >> 4) - 5) << 2; )
|
| 1461 |
|
|
{
|
| 1462 |
|
|
opt = uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + c];
|
| 1463 |
|
|
if( opt == TCP_OPT_END )
|
| 1464 |
|
|
{
|
| 1465 |
|
|
/* End of options. */
|
| 1466 |
|
|
break;
|
| 1467 |
|
|
}
|
| 1468 |
|
|
else if( opt == TCP_OPT_NOOP )
|
| 1469 |
|
|
{
|
| 1470 |
|
|
++c;
|
| 1471 |
|
|
|
| 1472 |
|
|
/* NOP option. */
|
| 1473 |
|
|
}
|
| 1474 |
|
|
else if( opt == TCP_OPT_MSS && uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == TCP_OPT_MSS_LEN )
|
| 1475 |
|
|
{
|
| 1476 |
|
|
/* An MSS option with the right option length. */
|
| 1477 |
|
|
tmp16 = ( (u16_t) uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 2 + c] << 8 ) | ( u16_t ) uip_buf[UIP_IPTCPH_LEN + UIP_LLH_LEN + 3 + c];
|
| 1478 |
|
|
uip_connr->initialmss = uip_connr->mss = tmp16 > UIP_TCP_MSS ? UIP_TCP_MSS : tmp16;
|
| 1479 |
|
|
|
| 1480 |
|
|
/* And we are done processing options. */
|
| 1481 |
|
|
break;
|
| 1482 |
|
|
}
|
| 1483 |
|
|
else
|
| 1484 |
|
|
{
|
| 1485 |
|
|
/* All other options have a length field, so that we easily
|
| 1486 |
|
|
can skip past them. */
|
| 1487 |
|
|
if( uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == 0 )
|
| 1488 |
|
|
{
|
| 1489 |
|
|
/* If the length field is zero, the options are malformed
|
| 1490 |
|
|
and we don't process them further. */
|
| 1491 |
|
|
break;
|
| 1492 |
|
|
}
|
| 1493 |
|
|
|
| 1494 |
|
|
c += uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c];
|
| 1495 |
|
|
}
|
| 1496 |
|
|
}
|
| 1497 |
|
|
}
|
| 1498 |
|
|
|
| 1499 |
|
|
/* Our response will be a SYNACK. */
|
| 1500 |
|
|
#if UIP_ACTIVE_OPEN
|
| 1501 |
|
|
tcp_send_synack : BUF->flags = TCP_ACK;
|
| 1502 |
|
|
tcp_send_syn:
|
| 1503 |
|
|
BUF->flags |= TCP_SYN;
|
| 1504 |
|
|
#else /* UIP_ACTIVE_OPEN */
|
| 1505 |
|
|
tcp_send_synack : BUF->flags = TCP_SYN | TCP_ACK;
|
| 1506 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 1507 |
|
|
|
| 1508 |
|
|
/* We send out the TCP Maximum Segment Size option with our
|
| 1509 |
|
|
SYNACK. */
|
| 1510 |
|
|
BUF->optdata[ 0 ] = TCP_OPT_MSS;
|
| 1511 |
|
|
BUF->optdata[ 1 ] = TCP_OPT_MSS_LEN;
|
| 1512 |
|
|
BUF->optdata[ 2 ] = ( UIP_TCP_MSS ) / 256;
|
| 1513 |
|
|
BUF->optdata[ 3 ] = ( UIP_TCP_MSS ) & 255;
|
| 1514 |
|
|
uip_len = UIP_IPTCPH_LEN + TCP_OPT_MSS_LEN;
|
| 1515 |
|
|
BUF->tcpoffset = ( (UIP_TCPH_LEN + TCP_OPT_MSS_LEN) / 4 ) << 4;
|
| 1516 |
|
|
goto tcp_send;
|
| 1517 |
|
|
|
| 1518 |
|
|
/* This label will be jumped to if we found an active connection. */
|
| 1519 |
|
|
found:
|
| 1520 |
|
|
uip_conn = uip_connr;
|
| 1521 |
|
|
uip_flags = 0;
|
| 1522 |
|
|
|
| 1523 |
|
|
/* We do a very naive form of TCP reset processing; we just accept
|
| 1524 |
|
|
any RST and kill our connection. We should in fact check if the
|
| 1525 |
|
|
sequence number of this reset is wihtin our advertised window
|
| 1526 |
|
|
before we accept the reset. */
|
| 1527 |
|
|
if( BUF->flags & TCP_RST )
|
| 1528 |
|
|
{
|
| 1529 |
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
| 1530 |
|
|
UIP_LOG( "tcp: got reset, aborting connection." );
|
| 1531 |
|
|
uip_flags = UIP_ABORT;
|
| 1532 |
|
|
UIP_APPCALL();
|
| 1533 |
|
|
goto drop;
|
| 1534 |
|
|
}
|
| 1535 |
|
|
|
| 1536 |
|
|
/* Calculate the length of the data, if the application has sent
|
| 1537 |
|
|
any data to us. */
|
| 1538 |
|
|
c = ( BUF->tcpoffset >> 4 ) << 2;
|
| 1539 |
|
|
|
| 1540 |
|
|
/* uip_len will contain the length of the actual TCP data. This is
|
| 1541 |
|
|
calculated by subtracing the length of the TCP header (in
|
| 1542 |
|
|
c) and the length of the IP header (20 bytes). */
|
| 1543 |
|
|
uip_len = uip_len - c - UIP_IPH_LEN;
|
| 1544 |
|
|
|
| 1545 |
|
|
/* First, check if the sequence number of the incoming packet is
|
| 1546 |
|
|
what we're expecting next. If not, we send out an ACK with the
|
| 1547 |
|
|
correct numbers in. */
|
| 1548 |
|
|
if( !(((uip_connr->tcpstateflags & UIP_TS_MASK) == UIP_SYN_SENT) && ((BUF->flags & TCP_CTL) == (TCP_SYN | TCP_ACK))) )
|
| 1549 |
|
|
{
|
| 1550 |
|
|
if
|
| 1551 |
|
|
(
|
| 1552 |
|
|
(uip_len > 0 || ((BUF->flags & (TCP_SYN | TCP_FIN)) != 0)) &&
|
| 1553 |
|
|
(
|
| 1554 |
|
|
BUF->seqno[ 0 ] != uip_connr->rcv_nxt[ 0 ] ||
|
| 1555 |
|
|
BUF->seqno[ 1 ] != uip_connr->rcv_nxt[ 1 ] ||
|
| 1556 |
|
|
BUF->seqno[ 2 ] != uip_connr->rcv_nxt[ 2 ] ||
|
| 1557 |
|
|
BUF->seqno[ 3 ] != uip_connr->rcv_nxt[ 3 ]
|
| 1558 |
|
|
)
|
| 1559 |
|
|
)
|
| 1560 |
|
|
{
|
| 1561 |
|
|
goto tcp_send_ack;
|
| 1562 |
|
|
}
|
| 1563 |
|
|
}
|
| 1564 |
|
|
|
| 1565 |
|
|
/* Next, check if the incoming segment acknowledges any outstanding
|
| 1566 |
|
|
data. If so, we update the sequence number, reset the length of
|
| 1567 |
|
|
the outstanding data, calculate RTT estimations, and reset the
|
| 1568 |
|
|
retransmission timer. */
|
| 1569 |
|
|
if( (BUF->flags & TCP_ACK) && uip_outstanding(uip_connr) )
|
| 1570 |
|
|
{
|
| 1571 |
|
|
uip_add32( uip_connr->snd_nxt, uip_connr->len );
|
| 1572 |
|
|
|
| 1573 |
|
|
if
|
| 1574 |
|
|
(
|
| 1575 |
|
|
BUF->ackno[ 0 ] == uip_acc32[ 0 ] &&
|
| 1576 |
|
|
BUF->ackno[ 1 ] == uip_acc32[ 1 ] &&
|
| 1577 |
|
|
BUF->ackno[ 2 ] == uip_acc32[ 2 ] &&
|
| 1578 |
|
|
BUF->ackno[ 3 ] == uip_acc32[ 3 ]
|
| 1579 |
|
|
)
|
| 1580 |
|
|
{
|
| 1581 |
|
|
/* Update sequence number. */
|
| 1582 |
|
|
uip_connr->snd_nxt[ 0 ] = uip_acc32[ 0 ];
|
| 1583 |
|
|
uip_connr->snd_nxt[ 1 ] = uip_acc32[ 1 ];
|
| 1584 |
|
|
uip_connr->snd_nxt[ 2 ] = uip_acc32[ 2 ];
|
| 1585 |
|
|
uip_connr->snd_nxt[ 3 ] = uip_acc32[ 3 ];
|
| 1586 |
|
|
|
| 1587 |
|
|
/* Do RTT estimation, unless we have done retransmissions. */
|
| 1588 |
|
|
if( uip_connr->nrtx == 0 )
|
| 1589 |
|
|
{
|
| 1590 |
|
|
signed char m;
|
| 1591 |
|
|
m = uip_connr->rto - uip_connr->timer;
|
| 1592 |
|
|
|
| 1593 |
|
|
/* This is taken directly from VJs original code in his paper */
|
| 1594 |
|
|
m = m - ( uip_connr->sa >> 3 );
|
| 1595 |
|
|
uip_connr->sa += m;
|
| 1596 |
|
|
if( m < 0 )
|
| 1597 |
|
|
{
|
| 1598 |
|
|
m = -m;
|
| 1599 |
|
|
}
|
| 1600 |
|
|
|
| 1601 |
|
|
m = m - ( uip_connr->sv >> 2 );
|
| 1602 |
|
|
uip_connr->sv += m;
|
| 1603 |
|
|
uip_connr->rto = ( uip_connr->sa >> 3 ) + uip_connr->sv;
|
| 1604 |
|
|
}
|
| 1605 |
|
|
|
| 1606 |
|
|
/* Set the acknowledged flag. */
|
| 1607 |
|
|
uip_flags = UIP_ACKDATA;
|
| 1608 |
|
|
|
| 1609 |
|
|
/* Reset the retransmission timer. */
|
| 1610 |
|
|
uip_connr->timer = uip_connr->rto;
|
| 1611 |
|
|
|
| 1612 |
|
|
/* Reset length of outstanding data. */
|
| 1613 |
|
|
uip_connr->len = 0;
|
| 1614 |
|
|
}
|
| 1615 |
|
|
}
|
| 1616 |
|
|
|
| 1617 |
|
|
/* Do different things depending on in what state the connection is. */
|
| 1618 |
|
|
switch( uip_connr->tcpstateflags & UIP_TS_MASK )
|
| 1619 |
|
|
{
|
| 1620 |
|
|
/* CLOSED and LISTEN are not handled here. CLOSE_WAIT is not
|
| 1621 |
|
|
implemented, since we force the application to close when the
|
| 1622 |
|
|
peer sends a FIN (hence the application goes directly from
|
| 1623 |
|
|
ESTABLISHED to LAST_ACK). */
|
| 1624 |
|
|
case UIP_SYN_RCVD:
|
| 1625 |
|
|
/* In SYN_RCVD we have sent out a SYNACK in response to a SYN, and
|
| 1626 |
|
|
we are waiting for an ACK that acknowledges the data we sent
|
| 1627 |
|
|
out the last time. Therefore, we want to have the UIP_ACKDATA
|
| 1628 |
|
|
flag set. If so, we enter the ESTABLISHED state. */
|
| 1629 |
|
|
if( uip_flags & UIP_ACKDATA )
|
| 1630 |
|
|
{
|
| 1631 |
|
|
uip_connr->tcpstateflags = UIP_ESTABLISHED;
|
| 1632 |
|
|
uip_flags = UIP_CONNECTED;
|
| 1633 |
|
|
uip_connr->len = 0;
|
| 1634 |
|
|
if( uip_len > 0 )
|
| 1635 |
|
|
{
|
| 1636 |
|
|
uip_flags |= UIP_NEWDATA;
|
| 1637 |
|
|
uip_add_rcv_nxt( uip_len );
|
| 1638 |
|
|
}
|
| 1639 |
|
|
|
| 1640 |
|
|
uip_slen = 0;
|
| 1641 |
|
|
UIP_APPCALL();
|
| 1642 |
|
|
goto appsend;
|
| 1643 |
|
|
}
|
| 1644 |
|
|
|
| 1645 |
|
|
goto drop;
|
| 1646 |
|
|
|
| 1647 |
|
|
#if UIP_ACTIVE_OPEN
|
| 1648 |
|
|
case UIP_SYN_SENT:
|
| 1649 |
|
|
/* In SYN_SENT, we wait for a SYNACK that is sent in response to
|
| 1650 |
|
|
our SYN. The rcv_nxt is set to sequence number in the SYNACK
|
| 1651 |
|
|
plus one, and we send an ACK. We move into the ESTABLISHED
|
| 1652 |
|
|
state. */
|
| 1653 |
|
|
if( (uip_flags & UIP_ACKDATA) && (BUF->flags & TCP_CTL) == (TCP_SYN | TCP_ACK) )
|
| 1654 |
|
|
{
|
| 1655 |
|
|
/* Parse the TCP MSS option, if present. */
|
| 1656 |
|
|
if( (BUF->tcpoffset & 0xf0) > 0x50 )
|
| 1657 |
|
|
{
|
| 1658 |
|
|
for( c = 0; c < ((BUF->tcpoffset >> 4) - 5) << 2; )
|
| 1659 |
|
|
{
|
| 1660 |
|
|
opt = uip_buf[UIP_IPTCPH_LEN + UIP_LLH_LEN + c];
|
| 1661 |
|
|
if( opt == TCP_OPT_END )
|
| 1662 |
|
|
{
|
| 1663 |
|
|
/* End of options. */
|
| 1664 |
|
|
break;
|
| 1665 |
|
|
}
|
| 1666 |
|
|
else if( opt == TCP_OPT_NOOP )
|
| 1667 |
|
|
{
|
| 1668 |
|
|
++c;
|
| 1669 |
|
|
|
| 1670 |
|
|
/* NOP option. */
|
| 1671 |
|
|
}
|
| 1672 |
|
|
else if( opt == TCP_OPT_MSS && uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == TCP_OPT_MSS_LEN )
|
| 1673 |
|
|
{
|
| 1674 |
|
|
/* An MSS option with the right option length. */
|
| 1675 |
|
|
tmp16 = ( uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 2 + c] << 8 ) | uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 3 + c];
|
| 1676 |
|
|
uip_connr->initialmss = uip_connr->mss = tmp16 > UIP_TCP_MSS ? UIP_TCP_MSS : tmp16;
|
| 1677 |
|
|
|
| 1678 |
|
|
/* And we are done processing options. */
|
| 1679 |
|
|
break;
|
| 1680 |
|
|
}
|
| 1681 |
|
|
else
|
| 1682 |
|
|
{
|
| 1683 |
|
|
/* All other options have a length field, so that we easily
|
| 1684 |
|
|
can skip past them. */
|
| 1685 |
|
|
if( uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c] == 0 )
|
| 1686 |
|
|
{
|
| 1687 |
|
|
/* If the length field is zero, the options are malformed
|
| 1688 |
|
|
and we don't process them further. */
|
| 1689 |
|
|
break;
|
| 1690 |
|
|
}
|
| 1691 |
|
|
|
| 1692 |
|
|
c += uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN + 1 + c];
|
| 1693 |
|
|
}
|
| 1694 |
|
|
}
|
| 1695 |
|
|
}
|
| 1696 |
|
|
|
| 1697 |
|
|
uip_connr->tcpstateflags = UIP_ESTABLISHED;
|
| 1698 |
|
|
uip_connr->rcv_nxt[ 0 ] = BUF->seqno[ 0 ];
|
| 1699 |
|
|
uip_connr->rcv_nxt[ 1 ] = BUF->seqno[ 1 ];
|
| 1700 |
|
|
uip_connr->rcv_nxt[ 2 ] = BUF->seqno[ 2 ];
|
| 1701 |
|
|
uip_connr->rcv_nxt[ 3 ] = BUF->seqno[ 3 ];
|
| 1702 |
|
|
uip_add_rcv_nxt( 1 );
|
| 1703 |
|
|
uip_flags = UIP_CONNECTED | UIP_NEWDATA;
|
| 1704 |
|
|
uip_connr->len = 0;
|
| 1705 |
|
|
uip_len = 0;
|
| 1706 |
|
|
uip_slen = 0;
|
| 1707 |
|
|
UIP_APPCALL();
|
| 1708 |
|
|
goto appsend;
|
| 1709 |
|
|
}
|
| 1710 |
|
|
|
| 1711 |
|
|
/* Inform the application that the connection failed */
|
| 1712 |
|
|
uip_flags = UIP_ABORT;
|
| 1713 |
|
|
UIP_APPCALL();
|
| 1714 |
|
|
|
| 1715 |
|
|
/* The connection is closed after we send the RST */
|
| 1716 |
|
|
uip_conn->tcpstateflags = UIP_CLOSED;
|
| 1717 |
|
|
goto reset;
|
| 1718 |
|
|
#endif /* UIP_ACTIVE_OPEN */
|
| 1719 |
|
|
|
| 1720 |
|
|
case UIP_ESTABLISHED:
|
| 1721 |
|
|
/* In the ESTABLISHED state, we call upon the application to feed
|
| 1722 |
|
|
data into the uip_buf. If the UIP_ACKDATA flag is set, the
|
| 1723 |
|
|
application should put new data into the buffer, otherwise we are
|
| 1724 |
|
|
retransmitting an old segment, and the application should put that
|
| 1725 |
|
|
data into the buffer.
|
| 1726 |
|
|
|
| 1727 |
|
|
If the incoming packet is a FIN, we should close the connection on
|
| 1728 |
|
|
this side as well, and we send out a FIN and enter the LAST_ACK
|
| 1729 |
|
|
state. We require that there is no outstanding data; otherwise the
|
| 1730 |
|
|
sequence numbers will be screwed up. */
|
| 1731 |
|
|
if( BUF->flags & TCP_FIN && !(uip_connr->tcpstateflags & UIP_STOPPED) )
|
| 1732 |
|
|
{
|
| 1733 |
|
|
if( uip_outstanding(uip_connr) )
|
| 1734 |
|
|
{
|
| 1735 |
|
|
goto drop;
|
| 1736 |
|
|
}
|
| 1737 |
|
|
|
| 1738 |
|
|
uip_add_rcv_nxt( 1 + uip_len );
|
| 1739 |
|
|
uip_flags |= UIP_CLOSE;
|
| 1740 |
|
|
if( uip_len > 0 )
|
| 1741 |
|
|
{
|
| 1742 |
|
|
uip_flags |= UIP_NEWDATA;
|
| 1743 |
|
|
}
|
| 1744 |
|
|
|
| 1745 |
|
|
UIP_APPCALL();
|
| 1746 |
|
|
uip_connr->len = 1;
|
| 1747 |
|
|
uip_connr->tcpstateflags = UIP_LAST_ACK;
|
| 1748 |
|
|
uip_connr->nrtx = 0;
|
| 1749 |
|
|
tcp_send_finack:
|
| 1750 |
|
|
BUF->flags = TCP_FIN | TCP_ACK;
|
| 1751 |
|
|
goto tcp_send_nodata;
|
| 1752 |
|
|
}
|
| 1753 |
|
|
|
| 1754 |
|
|
/* Check the URG flag. If this is set, the segment carries urgent
|
| 1755 |
|
|
data that we must pass to the application. */
|
| 1756 |
|
|
if( (BUF->flags & TCP_URG) != 0 )
|
| 1757 |
|
|
{
|
| 1758 |
|
|
#if UIP_URGDATA > 0
|
| 1759 |
|
|
uip_urglen = ( BUF->urgp[ 0 ] << 8 ) | BUF->urgp[ 1 ];
|
| 1760 |
|
|
if( uip_urglen > uip_len )
|
| 1761 |
|
|
{
|
| 1762 |
|
|
/* There is more urgent data in the next segment to come. */
|
| 1763 |
|
|
uip_urglen = uip_len;
|
| 1764 |
|
|
}
|
| 1765 |
|
|
|
| 1766 |
|
|
uip_add_rcv_nxt( uip_urglen );
|
| 1767 |
|
|
uip_len -= uip_urglen;
|
| 1768 |
|
|
uip_urgdata = uip_appdata;
|
| 1769 |
|
|
uip_appdata += uip_urglen;
|
| 1770 |
|
|
}
|
| 1771 |
|
|
else
|
| 1772 |
|
|
{
|
| 1773 |
|
|
uip_urglen = 0;
|
| 1774 |
|
|
#else /* UIP_URGDATA > 0 */
|
| 1775 |
|
|
uip_appdata = ( ( char * ) uip_appdata ) + ( (BUF->urgp[ 0 ] << 8) | BUF->urgp[ 1 ] );
|
| 1776 |
|
|
uip_len -= ( BUF->urgp[ 0 ] << 8 ) | BUF->urgp[ 1 ];
|
| 1777 |
|
|
#endif /* UIP_URGDATA > 0 */
|
| 1778 |
|
|
}
|
| 1779 |
|
|
|
| 1780 |
|
|
/* If uip_len > 0 we have TCP data in the packet, and we flag this
|
| 1781 |
|
|
by setting the UIP_NEWDATA flag and update the sequence number
|
| 1782 |
|
|
we acknowledge. If the application has stopped the dataflow
|
| 1783 |
|
|
using uip_stop(), we must not accept any data packets from the
|
| 1784 |
|
|
remote host. */
|
| 1785 |
|
|
if( uip_len > 0 && !(uip_connr->tcpstateflags & UIP_STOPPED) )
|
| 1786 |
|
|
{
|
| 1787 |
|
|
uip_flags |= UIP_NEWDATA;
|
| 1788 |
|
|
uip_add_rcv_nxt( uip_len );
|
| 1789 |
|
|
}
|
| 1790 |
|
|
|
| 1791 |
|
|
/* Check if the available buffer space advertised by the other end
|
| 1792 |
|
|
is smaller than the initial MSS for this connection. If so, we
|
| 1793 |
|
|
set the current MSS to the window size to ensure that the
|
| 1794 |
|
|
application does not send more data than the other end can
|
| 1795 |
|
|
handle.
|
| 1796 |
|
|
|
| 1797 |
|
|
If the remote host advertises a zero window, we set the MSS to
|
| 1798 |
|
|
the initial MSS so that the application will send an entire MSS
|
| 1799 |
|
|
of data. This data will not be acknowledged by the receiver,
|
| 1800 |
|
|
and the application will retransmit it. This is called the
|
| 1801 |
|
|
"persistent timer" and uses the retransmission mechanim.
|
| 1802 |
|
|
*/
|
| 1803 |
|
|
tmp16 = ( (u16_t) BUF->wnd[ 0 ] << 8 ) + ( u16_t ) BUF->wnd[ 1 ];
|
| 1804 |
|
|
if( tmp16 > uip_connr->initialmss || tmp16 == 0 )
|
| 1805 |
|
|
{
|
| 1806 |
|
|
tmp16 = uip_connr->initialmss;
|
| 1807 |
|
|
}
|
| 1808 |
|
|
|
| 1809 |
|
|
uip_connr->mss = tmp16;
|
| 1810 |
|
|
|
| 1811 |
|
|
/* If this packet constitutes an ACK for outstanding data (flagged
|
| 1812 |
|
|
by the UIP_ACKDATA flag, we should call the application since it
|
| 1813 |
|
|
might want to send more data. If the incoming packet had data
|
| 1814 |
|
|
from the peer (as flagged by the UIP_NEWDATA flag), the
|
| 1815 |
|
|
application must also be notified.
|
| 1816 |
|
|
|
| 1817 |
|
|
When the application is called, the global variable uip_len
|
| 1818 |
|
|
contains the length of the incoming data. The application can
|
| 1819 |
|
|
access the incoming data through the global pointer
|
| 1820 |
|
|
uip_appdata, which usually points UIP_IPTCPH_LEN + UIP_LLH_LEN
|
| 1821 |
|
|
bytes into the uip_buf array.
|
| 1822 |
|
|
|
| 1823 |
|
|
If the application wishes to send any data, this data should be
|
| 1824 |
|
|
put into the uip_appdata and the length of the data should be
|
| 1825 |
|
|
put into uip_len. If the application don't have any data to
|
| 1826 |
|
|
send, uip_len must be set to 0. */
|
| 1827 |
|
|
if( uip_flags & (UIP_NEWDATA | UIP_ACKDATA) )
|
| 1828 |
|
|
{
|
| 1829 |
|
|
uip_slen = 0;
|
| 1830 |
|
|
UIP_APPCALL();
|
| 1831 |
|
|
|
| 1832 |
|
|
appsend:
|
| 1833 |
|
|
if( uip_flags & UIP_ABORT )
|
| 1834 |
|
|
{
|
| 1835 |
|
|
uip_slen = 0;
|
| 1836 |
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
| 1837 |
|
|
BUF->flags = TCP_RST | TCP_ACK;
|
| 1838 |
|
|
goto tcp_send_nodata;
|
| 1839 |
|
|
}
|
| 1840 |
|
|
|
| 1841 |
|
|
if( uip_flags & UIP_CLOSE )
|
| 1842 |
|
|
{
|
| 1843 |
|
|
uip_slen = 0;
|
| 1844 |
|
|
uip_connr->len = 1;
|
| 1845 |
|
|
uip_connr->tcpstateflags = UIP_FIN_WAIT_1;
|
| 1846 |
|
|
uip_connr->nrtx = 0;
|
| 1847 |
|
|
BUF->flags = TCP_FIN | TCP_ACK;
|
| 1848 |
|
|
goto tcp_send_nodata;
|
| 1849 |
|
|
}
|
| 1850 |
|
|
|
| 1851 |
|
|
/* If uip_slen > 0, the application has data to be sent. */
|
| 1852 |
|
|
if( uip_slen > 0 )
|
| 1853 |
|
|
{
|
| 1854 |
|
|
/* If the connection has acknowledged data, the contents of
|
| 1855 |
|
|
the ->len variable should be discarded. */
|
| 1856 |
|
|
if( (uip_flags & UIP_ACKDATA) != 0 )
|
| 1857 |
|
|
{
|
| 1858 |
|
|
uip_connr->len = 0;
|
| 1859 |
|
|
}
|
| 1860 |
|
|
|
| 1861 |
|
|
/* If the ->len variable is non-zero the connection has
|
| 1862 |
|
|
already data in transit and cannot send anymore right
|
| 1863 |
|
|
now. */
|
| 1864 |
|
|
if( uip_connr->len == 0 )
|
| 1865 |
|
|
{
|
| 1866 |
|
|
/* The application cannot send more than what is allowed by
|
| 1867 |
|
|
the mss (the minumum of the MSS and the available
|
| 1868 |
|
|
window). */
|
| 1869 |
|
|
if( uip_slen > uip_connr->mss )
|
| 1870 |
|
|
{
|
| 1871 |
|
|
uip_slen = uip_connr->mss;
|
| 1872 |
|
|
}
|
| 1873 |
|
|
|
| 1874 |
|
|
/* Remember how much data we send out now so that we know
|
| 1875 |
|
|
when everything has been acknowledged. */
|
| 1876 |
|
|
uip_connr->len = uip_slen;
|
| 1877 |
|
|
}
|
| 1878 |
|
|
else
|
| 1879 |
|
|
{
|
| 1880 |
|
|
/* If the application already had unacknowledged data, we
|
| 1881 |
|
|
make sure that the application does not send (i.e.,
|
| 1882 |
|
|
retransmit) out more than it previously sent out. */
|
| 1883 |
|
|
uip_slen = uip_connr->len;
|
| 1884 |
|
|
}
|
| 1885 |
|
|
}
|
| 1886 |
|
|
|
| 1887 |
|
|
uip_connr->nrtx = 0;
|
| 1888 |
|
|
apprexmit:
|
| 1889 |
|
|
uip_appdata = uip_sappdata;
|
| 1890 |
|
|
|
| 1891 |
|
|
/* If the application has data to be sent, or if the incoming
|
| 1892 |
|
|
packet had new data in it, we must send out a packet. */
|
| 1893 |
|
|
if( uip_slen > 0 && uip_connr->len > 0 )
|
| 1894 |
|
|
{
|
| 1895 |
|
|
/* Add the length of the IP and TCP headers. */
|
| 1896 |
|
|
uip_len = uip_connr->len + UIP_TCPIP_HLEN;
|
| 1897 |
|
|
|
| 1898 |
|
|
/* We always set the ACK flag in response packets. */
|
| 1899 |
|
|
BUF->flags = TCP_ACK | TCP_PSH;
|
| 1900 |
|
|
|
| 1901 |
|
|
/* Send the packet. */
|
| 1902 |
|
|
goto tcp_send_noopts;
|
| 1903 |
|
|
}
|
| 1904 |
|
|
|
| 1905 |
|
|
/* If there is no data to send, just send out a pure ACK if
|
| 1906 |
|
|
there is newdata. */
|
| 1907 |
|
|
if( uip_flags & UIP_NEWDATA )
|
| 1908 |
|
|
{
|
| 1909 |
|
|
uip_len = UIP_TCPIP_HLEN;
|
| 1910 |
|
|
BUF->flags = TCP_ACK;
|
| 1911 |
|
|
goto tcp_send_noopts;
|
| 1912 |
|
|
}
|
| 1913 |
|
|
}
|
| 1914 |
|
|
|
| 1915 |
|
|
goto drop;
|
| 1916 |
|
|
|
| 1917 |
|
|
case UIP_LAST_ACK:
|
| 1918 |
|
|
/* We can close this connection if the peer has acknowledged our
|
| 1919 |
|
|
FIN. This is indicated by the UIP_ACKDATA flag. */
|
| 1920 |
|
|
if( uip_flags & UIP_ACKDATA )
|
| 1921 |
|
|
{
|
| 1922 |
|
|
uip_connr->tcpstateflags = UIP_CLOSED;
|
| 1923 |
|
|
uip_flags = UIP_CLOSE;
|
| 1924 |
|
|
UIP_APPCALL();
|
| 1925 |
|
|
}
|
| 1926 |
|
|
|
| 1927 |
|
|
break;
|
| 1928 |
|
|
|
| 1929 |
|
|
case UIP_FIN_WAIT_1:
|
| 1930 |
|
|
/* The application has closed the connection, but the remote host
|
| 1931 |
|
|
hasn't closed its end yet. Thus we do nothing but wait for a
|
| 1932 |
|
|
FIN from the other side. */
|
| 1933 |
|
|
if( uip_len > 0 )
|
| 1934 |
|
|
{
|
| 1935 |
|
|
uip_add_rcv_nxt( uip_len );
|
| 1936 |
|
|
}
|
| 1937 |
|
|
|
| 1938 |
|
|
if( BUF->flags & TCP_FIN )
|
| 1939 |
|
|
{
|
| 1940 |
|
|
if( uip_flags & UIP_ACKDATA )
|
| 1941 |
|
|
{
|
| 1942 |
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
| 1943 |
|
|
uip_connr->timer = 0;
|
| 1944 |
|
|
uip_connr->len = 0;
|
| 1945 |
|
|
}
|
| 1946 |
|
|
else
|
| 1947 |
|
|
{
|
| 1948 |
|
|
uip_connr->tcpstateflags = UIP_CLOSING;
|
| 1949 |
|
|
}
|
| 1950 |
|
|
|
| 1951 |
|
|
uip_add_rcv_nxt( 1 );
|
| 1952 |
|
|
uip_flags = UIP_CLOSE;
|
| 1953 |
|
|
UIP_APPCALL();
|
| 1954 |
|
|
goto tcp_send_ack;
|
| 1955 |
|
|
}
|
| 1956 |
|
|
else if( uip_flags & UIP_ACKDATA )
|
| 1957 |
|
|
{
|
| 1958 |
|
|
uip_connr->tcpstateflags = UIP_FIN_WAIT_2;
|
| 1959 |
|
|
uip_connr->len = 0;
|
| 1960 |
|
|
goto drop;
|
| 1961 |
|
|
}
|
| 1962 |
|
|
|
| 1963 |
|
|
if( uip_len > 0 )
|
| 1964 |
|
|
{
|
| 1965 |
|
|
goto tcp_send_ack;
|
| 1966 |
|
|
}
|
| 1967 |
|
|
|
| 1968 |
|
|
goto drop;
|
| 1969 |
|
|
|
| 1970 |
|
|
case UIP_FIN_WAIT_2:
|
| 1971 |
|
|
if( uip_len > 0 )
|
| 1972 |
|
|
{
|
| 1973 |
|
|
uip_add_rcv_nxt( uip_len );
|
| 1974 |
|
|
}
|
| 1975 |
|
|
|
| 1976 |
|
|
if( BUF->flags & TCP_FIN )
|
| 1977 |
|
|
{
|
| 1978 |
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
| 1979 |
|
|
uip_connr->timer = 0;
|
| 1980 |
|
|
uip_add_rcv_nxt( 1 );
|
| 1981 |
|
|
uip_flags = UIP_CLOSE;
|
| 1982 |
|
|
UIP_APPCALL();
|
| 1983 |
|
|
goto tcp_send_ack;
|
| 1984 |
|
|
}
|
| 1985 |
|
|
|
| 1986 |
|
|
if( uip_len > 0 )
|
| 1987 |
|
|
{
|
| 1988 |
|
|
goto tcp_send_ack;
|
| 1989 |
|
|
}
|
| 1990 |
|
|
|
| 1991 |
|
|
goto drop;
|
| 1992 |
|
|
|
| 1993 |
|
|
case UIP_TIME_WAIT:
|
| 1994 |
|
|
goto tcp_send_ack;
|
| 1995 |
|
|
|
| 1996 |
|
|
case UIP_CLOSING:
|
| 1997 |
|
|
if( uip_flags & UIP_ACKDATA )
|
| 1998 |
|
|
{
|
| 1999 |
|
|
uip_connr->tcpstateflags = UIP_TIME_WAIT;
|
| 2000 |
|
|
uip_connr->timer = 0;
|
| 2001 |
|
|
}
|
| 2002 |
|
|
}
|
| 2003 |
|
|
|
| 2004 |
|
|
goto drop;
|
| 2005 |
|
|
|
| 2006 |
|
|
/* We jump here when we are ready to send the packet, and just want
|
| 2007 |
|
|
to set the appropriate TCP sequence numbers in the TCP header. */
|
| 2008 |
|
|
tcp_send_ack:
|
| 2009 |
|
|
BUF->flags = TCP_ACK;
|
| 2010 |
|
|
|
| 2011 |
|
|
tcp_send_nodata:
|
| 2012 |
|
|
uip_len = UIP_IPTCPH_LEN;
|
| 2013 |
|
|
|
| 2014 |
|
|
tcp_send_noopts:
|
| 2015 |
|
|
BUF->tcpoffset = ( UIP_TCPH_LEN / 4 ) << 4;
|
| 2016 |
|
|
|
| 2017 |
|
|
/* We're done with the input processing. We are now ready to send a
|
| 2018 |
|
|
reply. Our job is to fill in all the fields of the TCP and IP
|
| 2019 |
|
|
headers before calculating the checksum and finally send the
|
| 2020 |
|
|
packet. */
|
| 2021 |
|
|
tcp_send:
|
| 2022 |
|
|
BUF->ackno[ 0 ] = uip_connr->rcv_nxt[ 0 ];
|
| 2023 |
|
|
BUF->ackno[ 1 ] = uip_connr->rcv_nxt[ 1 ];
|
| 2024 |
|
|
BUF->ackno[ 2 ] = uip_connr->rcv_nxt[ 2 ];
|
| 2025 |
|
|
BUF->ackno[ 3 ] = uip_connr->rcv_nxt[ 3 ];
|
| 2026 |
|
|
|
| 2027 |
|
|
BUF->seqno[ 0 ] = uip_connr->snd_nxt[ 0 ];
|
| 2028 |
|
|
BUF->seqno[ 1 ] = uip_connr->snd_nxt[ 1 ];
|
| 2029 |
|
|
BUF->seqno[ 2 ] = uip_connr->snd_nxt[ 2 ];
|
| 2030 |
|
|
BUF->seqno[ 3 ] = uip_connr->snd_nxt[ 3 ];
|
| 2031 |
|
|
|
| 2032 |
|
|
BUF->proto = UIP_PROTO_TCP;
|
| 2033 |
|
|
|
| 2034 |
|
|
BUF->srcport = uip_connr->lport;
|
| 2035 |
|
|
BUF->destport = uip_connr->rport;
|
| 2036 |
|
|
|
| 2037 |
|
|
uip_ipaddr_copy( &BUF->srcipaddr, &uip_hostaddr );
|
| 2038 |
|
|
uip_ipaddr_copy( &BUF->destipaddr, &uip_connr->ripaddr );
|
| 2039 |
|
|
|
| 2040 |
|
|
if( uip_connr->tcpstateflags & UIP_STOPPED )
|
| 2041 |
|
|
{
|
| 2042 |
|
|
/* If the connection has issued uip_stop(), we advertise a zero
|
| 2043 |
|
|
window so that the remote host will stop sending data. */
|
| 2044 |
|
|
BUF->wnd[ 0 ] = BUF->wnd[ 1 ] = 0;
|
| 2045 |
|
|
}
|
| 2046 |
|
|
else
|
| 2047 |
|
|
{
|
| 2048 |
|
|
BUF->wnd[ 0 ] = ( (UIP_RECEIVE_WINDOW) >> 8 );
|
| 2049 |
|
|
BUF->wnd[ 1 ] = ( (UIP_RECEIVE_WINDOW) & 0xff );
|
| 2050 |
|
|
}
|
| 2051 |
|
|
|
| 2052 |
|
|
tcp_send_noconn:
|
| 2053 |
|
|
|
| 2054 |
|
|
BUF->ttl = UIP_TTL;
|
| 2055 |
|
|
|
| 2056 |
|
|
#if UIP_CONF_IPV6
|
| 2057 |
|
|
/* For IPv6, the IP length field does not include the IPv6 IP header
|
| 2058 |
|
|
length. */
|
| 2059 |
|
|
BUF->len[ 0 ] = ( (uip_len - UIP_IPH_LEN) >> 8 );
|
| 2060 |
|
|
BUF->len[ 1 ] = ( (uip_len - UIP_IPH_LEN) & 0xff );
|
| 2061 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 2062 |
|
|
BUF->len[ 0 ] = ( uip_len >> 8 );
|
| 2063 |
|
|
BUF->len[ 1 ] = ( uip_len & 0xff );
|
| 2064 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 2065 |
|
|
|
| 2066 |
|
|
BUF->urgp[ 0 ] = BUF->urgp[ 1 ] = 0;
|
| 2067 |
|
|
|
| 2068 |
|
|
/* Calculate TCP checksum. */
|
| 2069 |
|
|
BUF->tcpchksum = 0;
|
| 2070 |
|
|
BUF->tcpchksum = ~( uip_tcpchksum() );
|
| 2071 |
|
|
|
| 2072 |
|
|
ip_send_nolen:
|
| 2073 |
|
|
#if UIP_CONF_IPV6
|
| 2074 |
|
|
BUF->vtc = 0x60;
|
| 2075 |
|
|
BUF->tcflow = 0x00;
|
| 2076 |
|
|
BUF->flow = 0x00;
|
| 2077 |
|
|
#else /* UIP_CONF_IPV6 */
|
| 2078 |
|
|
BUF->vhl = 0x45;
|
| 2079 |
|
|
BUF->tos = 0;
|
| 2080 |
|
|
BUF->ipoffset[ 0 ] = BUF->ipoffset[ 1 ] = 0;
|
| 2081 |
|
|
++ipid;
|
| 2082 |
|
|
BUF->ipid[ 0 ] = ipid >> 8;
|
| 2083 |
|
|
BUF->ipid[ 1 ] = ipid & 0xff;
|
| 2084 |
|
|
|
| 2085 |
|
|
/* Calculate IP checksum. */
|
| 2086 |
|
|
BUF->ipchksum = 0;
|
| 2087 |
|
|
BUF->ipchksum = ~( uip_ipchksum() );
|
| 2088 |
|
|
|
| 2089 |
|
|
//DEBUG_PRINTF( "uip ip_send_nolen: chkecum 0x%04x\n", uip_ipchksum() );
|
| 2090 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 2091 |
|
|
|
| 2092 |
|
|
UIP_STAT( ++uip_stat.tcp.sent );
|
| 2093 |
|
|
|
| 2094 |
|
|
#if UIP_CONF_IPV6
|
| 2095 |
|
|
send :
|
| 2096 |
|
|
#endif /* UIP_CONF_IPV6 */
|
| 2097 |
|
|
|
| 2098 |
|
|
//DEBUG_PRINTF( "Sending packet with length %d (%d)\n", uip_len, (BUF->len[ 0 ] << 8) | BUF->len[ 1 ] );
|
| 2099 |
|
|
UIP_STAT( ++uip_stat.ip.sent );
|
| 2100 |
|
|
|
| 2101 |
|
|
/* Return and let the caller do the actual transmission. */
|
| 2102 |
|
|
uip_flags = 0;
|
| 2103 |
|
|
return;
|
| 2104 |
|
|
|
| 2105 |
|
|
drop:
|
| 2106 |
|
|
uip_len = 0;
|
| 2107 |
|
|
uip_flags = 0;
|
| 2108 |
|
|
return;
|
| 2109 |
|
|
}
|
| 2110 |
|
|
/*---------------------------------------------------------------------------*/
|
| 2111 |
|
|
|
| 2112 |
|
|
u16_t htons( u16_t val )
|
| 2113 |
|
|
{
|
| 2114 |
|
|
return HTONS( val );
|
| 2115 |
|
|
}
|
| 2116 |
|
|
|
| 2117 |
|
|
u32_t htonl( u32_t val )
|
| 2118 |
|
|
{
|
| 2119 |
|
|
return HTONL( val );
|
| 2120 |
|
|
}
|
| 2121 |
|
|
/*---------------------------------------------------------------------------*/
|
| 2122 |
|
|
|
| 2123 |
|
|
void uip_send( const void *data, int len )
|
| 2124 |
|
|
{
|
| 2125 |
|
|
int copylen;
|
| 2126 |
|
|
|
| 2127 |
|
|
#define MIN( a, b ) ( (a) < (b) ? (a) : (b) )
|
| 2128 |
|
|
|
| 2129 |
|
|
copylen = MIN( len, UIP_BUFSIZE - UIP_LLH_LEN - UIP_TCPIP_HLEN - ( int )
|
| 2130 |
|
|
(( char * ) uip_sappdata - ( char * ) &uip_buf[UIP_LLH_LEN + UIP_TCPIP_HLEN]) );
|
| 2131 |
|
|
if( copylen > 0 )
|
| 2132 |
|
|
{
|
| 2133 |
|
|
uip_slen = copylen;
|
| 2134 |
|
|
if( data != uip_sappdata )
|
| 2135 |
|
|
{
|
| 2136 |
|
|
memcpy( uip_sappdata, (data), uip_slen );
|
| 2137 |
|
|
}
|
| 2138 |
|
|
}
|
| 2139 |
|
|
}
|
| 2140 |
|
|
/*---------------------------------------------------------------------------*/
|
| 2141 |
|
|
|
| 2142 |
|
|
/** @} */
|
| 2143 |
|
|
#endif /* UIP_CONF_IPV6 */
|
