Yasushi TAUCHI / Mbed 2 deprecated giken9_HTMLServer_Sample

ソースの整理中ですが、利用はできます。

Dependencies:   EthernetInterface HttpServer TextLCD mbed-rpc mbed-rtos mbed Socket lwip-eth lwip-sys lwip

EthernetInterface/lwip/core/ipv4/inet_chksum.c@0:7766f6712673, 2014-03-12 (annotated)

Committer:
yueee_yt
Date:
Wed Mar 12 04:19:54 2014 +0000
Revision:
0:7766f6712673
???????????????

Who changed what in which revision?

UserRevisionLine numberNew contents of line
yueee_yt 0:7766f6712673 1 /**
yueee_yt 0:7766f6712673 2 * @file
yueee_yt 0:7766f6712673 3 * Incluse internet checksum functions.
yueee_yt 0:7766f6712673 4 *
yueee_yt 0:7766f6712673 5 */
yueee_yt 0:7766f6712673 6
yueee_yt 0:7766f6712673 7 /*
yueee_yt 0:7766f6712673 8 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
yueee_yt 0:7766f6712673 9 * All rights reserved.
yueee_yt 0:7766f6712673 10 *
yueee_yt 0:7766f6712673 11 * Redistribution and use in source and binary forms, with or without modification,
yueee_yt 0:7766f6712673 12 * are permitted provided that the following conditions are met:
yueee_yt 0:7766f6712673 13 *
yueee_yt 0:7766f6712673 14 * 1. Redistributions of source code must retain the above copyright notice,
yueee_yt 0:7766f6712673 15 * this list of conditions and the following disclaimer.
yueee_yt 0:7766f6712673 16 * 2. Redistributions in binary form must reproduce the above copyright notice,
yueee_yt 0:7766f6712673 17 * this list of conditions and the following disclaimer in the documentation
yueee_yt 0:7766f6712673 18 * and/or other materials provided with the distribution.
yueee_yt 0:7766f6712673 19 * 3. The name of the author may not be used to endorse or promote products
yueee_yt 0:7766f6712673 20 * derived from this software without specific prior written permission.
yueee_yt 0:7766f6712673 21 *
yueee_yt 0:7766f6712673 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
yueee_yt 0:7766f6712673 23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
yueee_yt 0:7766f6712673 24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
yueee_yt 0:7766f6712673 25 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
yueee_yt 0:7766f6712673 26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
yueee_yt 0:7766f6712673 27 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
yueee_yt 0:7766f6712673 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
yueee_yt 0:7766f6712673 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
yueee_yt 0:7766f6712673 30 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
yueee_yt 0:7766f6712673 31 * OF SUCH DAMAGE.
yueee_yt 0:7766f6712673 32 *
yueee_yt 0:7766f6712673 33 * This file is part of the lwIP TCP/IP stack.
yueee_yt 0:7766f6712673 34 *
yueee_yt 0:7766f6712673 35 * Author: Adam Dunkels <adam@sics.se>
yueee_yt 0:7766f6712673 36 *
yueee_yt 0:7766f6712673 37 */
yueee_yt 0:7766f6712673 38
yueee_yt 0:7766f6712673 39 #include "lwip/opt.h"
yueee_yt 0:7766f6712673 40
yueee_yt 0:7766f6712673 41 #include "lwip/inet_chksum.h"
yueee_yt 0:7766f6712673 42 #include "lwip/def.h"
yueee_yt 0:7766f6712673 43
yueee_yt 0:7766f6712673 44 #include <stddef.h>
yueee_yt 0:7766f6712673 45 #include <string.h>
yueee_yt 0:7766f6712673 46
yueee_yt 0:7766f6712673 47 /* These are some reference implementations of the checksum algorithm, with the
yueee_yt 0:7766f6712673 48 * aim of being simple, correct and fully portable. Checksumming is the
yueee_yt 0:7766f6712673 49 * first thing you would want to optimize for your platform. If you create
yueee_yt 0:7766f6712673 50 * your own version, link it in and in your cc.h put:
yueee_yt 0:7766f6712673 51 *
yueee_yt 0:7766f6712673 52 * #define LWIP_CHKSUM <your_checksum_routine>
yueee_yt 0:7766f6712673 53 *
yueee_yt 0:7766f6712673 54 * Or you can select from the implementations below by defining
yueee_yt 0:7766f6712673 55 * LWIP_CHKSUM_ALGORITHM to 1, 2 or 3.
yueee_yt 0:7766f6712673 56 */
yueee_yt 0:7766f6712673 57
yueee_yt 0:7766f6712673 58 #ifndef LWIP_CHKSUM
yueee_yt 0:7766f6712673 59 # define LWIP_CHKSUM lwip_standard_chksum
yueee_yt 0:7766f6712673 60 # ifndef LWIP_CHKSUM_ALGORITHM
yueee_yt 0:7766f6712673 61 # define LWIP_CHKSUM_ALGORITHM 2
yueee_yt 0:7766f6712673 62 # endif
yueee_yt 0:7766f6712673 63 #endif
yueee_yt 0:7766f6712673 64 /* If none set: */
yueee_yt 0:7766f6712673 65 #ifndef LWIP_CHKSUM_ALGORITHM
yueee_yt 0:7766f6712673 66 # define LWIP_CHKSUM_ALGORITHM 0
yueee_yt 0:7766f6712673 67 #endif
yueee_yt 0:7766f6712673 68
yueee_yt 0:7766f6712673 69 #if (LWIP_CHKSUM_ALGORITHM == 1) /* Version #1 */
yueee_yt 0:7766f6712673 70 /**
yueee_yt 0:7766f6712673 71 * lwip checksum
yueee_yt 0:7766f6712673 72 *
yueee_yt 0:7766f6712673 73 * @param dataptr points to start of data to be summed at any boundary
yueee_yt 0:7766f6712673 74 * @param len length of data to be summed
yueee_yt 0:7766f6712673 75 * @return host order (!) lwip checksum (non-inverted Internet sum)
yueee_yt 0:7766f6712673 76 *
yueee_yt 0:7766f6712673 77 * @note accumulator size limits summable length to 64k
yueee_yt 0:7766f6712673 78 * @note host endianess is irrelevant (p3 RFC1071)
yueee_yt 0:7766f6712673 79 */
yueee_yt 0:7766f6712673 80 static u16_t
yueee_yt 0:7766f6712673 81 lwip_standard_chksum(void *dataptr, u16_t len)
yueee_yt 0:7766f6712673 82 {
yueee_yt 0:7766f6712673 83 u32_t acc;
yueee_yt 0:7766f6712673 84 u16_t src;
yueee_yt 0:7766f6712673 85 u8_t *octetptr;
yueee_yt 0:7766f6712673 86
yueee_yt 0:7766f6712673 87 acc = 0;
yueee_yt 0:7766f6712673 88 /* dataptr may be at odd or even addresses */
yueee_yt 0:7766f6712673 89 octetptr = (u8_t*)dataptr;
yueee_yt 0:7766f6712673 90 while (len > 1) {
yueee_yt 0:7766f6712673 91 /* declare first octet as most significant
yueee_yt 0:7766f6712673 92 thus assume network order, ignoring host order */
yueee_yt 0:7766f6712673 93 src = (*octetptr) << 8;
yueee_yt 0:7766f6712673 94 octetptr++;
yueee_yt 0:7766f6712673 95 /* declare second octet as least significant */
yueee_yt 0:7766f6712673 96 src |= (*octetptr);
yueee_yt 0:7766f6712673 97 octetptr++;
yueee_yt 0:7766f6712673 98 acc += src;
yueee_yt 0:7766f6712673 99 len -= 2;
yueee_yt 0:7766f6712673 100 }
yueee_yt 0:7766f6712673 101 if (len > 0) {
yueee_yt 0:7766f6712673 102 /* accumulate remaining octet */
yueee_yt 0:7766f6712673 103 src = (*octetptr) << 8;
yueee_yt 0:7766f6712673 104 acc += src;
yueee_yt 0:7766f6712673 105 }
yueee_yt 0:7766f6712673 106 /* add deferred carry bits */
yueee_yt 0:7766f6712673 107 acc = (acc >> 16) + (acc & 0x0000ffffUL);
yueee_yt 0:7766f6712673 108 if ((acc & 0xffff0000UL) != 0) {
yueee_yt 0:7766f6712673 109 acc = (acc >> 16) + (acc & 0x0000ffffUL);
yueee_yt 0:7766f6712673 110 }
yueee_yt 0:7766f6712673 111 /* This maybe a little confusing: reorder sum using htons()
yueee_yt 0:7766f6712673 112 instead of ntohs() since it has a little less call overhead.
yueee_yt 0:7766f6712673 113 The caller must invert bits for Internet sum ! */
yueee_yt 0:7766f6712673 114 return htons((u16_t)acc);
yueee_yt 0:7766f6712673 115 }
yueee_yt 0:7766f6712673 116 #endif
yueee_yt 0:7766f6712673 117
yueee_yt 0:7766f6712673 118 #if (LWIP_CHKSUM_ALGORITHM == 2) /* Alternative version #2 */
yueee_yt 0:7766f6712673 119 /*
yueee_yt 0:7766f6712673 120 * Curt McDowell
yueee_yt 0:7766f6712673 121 * Broadcom Corp.
yueee_yt 0:7766f6712673 122 * csm@broadcom.com
yueee_yt 0:7766f6712673 123 *
yueee_yt 0:7766f6712673 124 * IP checksum two bytes at a time with support for
yueee_yt 0:7766f6712673 125 * unaligned buffer.
yueee_yt 0:7766f6712673 126 * Works for len up to and including 0x20000.
yueee_yt 0:7766f6712673 127 * by Curt McDowell, Broadcom Corp. 12/08/2005
yueee_yt 0:7766f6712673 128 *
yueee_yt 0:7766f6712673 129 * @param dataptr points to start of data to be summed at any boundary
yueee_yt 0:7766f6712673 130 * @param len length of data to be summed
yueee_yt 0:7766f6712673 131 * @return host order (!) lwip checksum (non-inverted Internet sum)
yueee_yt 0:7766f6712673 132 */
yueee_yt 0:7766f6712673 133
yueee_yt 0:7766f6712673 134 static u16_t
yueee_yt 0:7766f6712673 135 lwip_standard_chksum(void *dataptr, int len)
yueee_yt 0:7766f6712673 136 {
yueee_yt 0:7766f6712673 137 u8_t *pb = (u8_t *)dataptr;
yueee_yt 0:7766f6712673 138 u16_t *ps, t = 0;
yueee_yt 0:7766f6712673 139 u32_t sum = 0;
yueee_yt 0:7766f6712673 140 int odd = ((mem_ptr_t)pb & 1);
yueee_yt 0:7766f6712673 141
yueee_yt 0:7766f6712673 142 /* Get aligned to u16_t */
yueee_yt 0:7766f6712673 143 if (odd && len > 0) {
yueee_yt 0:7766f6712673 144 ((u8_t *)&t)[1] = *pb++;
yueee_yt 0:7766f6712673 145 len--;
yueee_yt 0:7766f6712673 146 }
yueee_yt 0:7766f6712673 147
yueee_yt 0:7766f6712673 148 /* Add the bulk of the data */
yueee_yt 0:7766f6712673 149 ps = (u16_t *)(void *)pb;
yueee_yt 0:7766f6712673 150 while (len > 1) {
yueee_yt 0:7766f6712673 151 sum += *ps++;
yueee_yt 0:7766f6712673 152 len -= 2;
yueee_yt 0:7766f6712673 153 }
yueee_yt 0:7766f6712673 154
yueee_yt 0:7766f6712673 155 /* Consume left-over byte, if any */
yueee_yt 0:7766f6712673 156 if (len > 0) {
yueee_yt 0:7766f6712673 157 ((u8_t *)&t)[0] = *(u8_t *)ps;
yueee_yt 0:7766f6712673 158 }
yueee_yt 0:7766f6712673 159
yueee_yt 0:7766f6712673 160 /* Add end bytes */
yueee_yt 0:7766f6712673 161 sum += t;
yueee_yt 0:7766f6712673 162
yueee_yt 0:7766f6712673 163 /* Fold 32-bit sum to 16 bits
yueee_yt 0:7766f6712673 164 calling this twice is propably faster than if statements... */
yueee_yt 0:7766f6712673 165 sum = FOLD_U32T(sum);
yueee_yt 0:7766f6712673 166 sum = FOLD_U32T(sum);
yueee_yt 0:7766f6712673 167
yueee_yt 0:7766f6712673 168 /* Swap if alignment was odd */
yueee_yt 0:7766f6712673 169 if (odd) {
yueee_yt 0:7766f6712673 170 sum = SWAP_BYTES_IN_WORD(sum);
yueee_yt 0:7766f6712673 171 }
yueee_yt 0:7766f6712673 172
yueee_yt 0:7766f6712673 173 return (u16_t)sum;
yueee_yt 0:7766f6712673 174 }
yueee_yt 0:7766f6712673 175 #endif
yueee_yt 0:7766f6712673 176
yueee_yt 0:7766f6712673 177 #if (LWIP_CHKSUM_ALGORITHM == 3) /* Alternative version #3 */
yueee_yt 0:7766f6712673 178 /**
yueee_yt 0:7766f6712673 179 * An optimized checksum routine. Basically, it uses loop-unrolling on
yueee_yt 0:7766f6712673 180 * the checksum loop, treating the head and tail bytes specially, whereas
yueee_yt 0:7766f6712673 181 * the inner loop acts on 8 bytes at a time.
yueee_yt 0:7766f6712673 182 *
yueee_yt 0:7766f6712673 183 * @arg start of buffer to be checksummed. May be an odd byte address.
yueee_yt 0:7766f6712673 184 * @len number of bytes in the buffer to be checksummed.
yueee_yt 0:7766f6712673 185 * @return host order (!) lwip checksum (non-inverted Internet sum)
yueee_yt 0:7766f6712673 186 *
yueee_yt 0:7766f6712673 187 * by Curt McDowell, Broadcom Corp. December 8th, 2005
yueee_yt 0:7766f6712673 188 */
yueee_yt 0:7766f6712673 189
yueee_yt 0:7766f6712673 190 static u16_t
yueee_yt 0:7766f6712673 191 lwip_standard_chksum(void *dataptr, int len)
yueee_yt 0:7766f6712673 192 {
yueee_yt 0:7766f6712673 193 u8_t *pb = (u8_t *)dataptr;
yueee_yt 0:7766f6712673 194 u16_t *ps, t = 0;
yueee_yt 0:7766f6712673 195 u32_t *pl;
yueee_yt 0:7766f6712673 196 u32_t sum = 0, tmp;
yueee_yt 0:7766f6712673 197 /* starts at odd byte address? */
yueee_yt 0:7766f6712673 198 int odd = ((mem_ptr_t)pb & 1);
yueee_yt 0:7766f6712673 199
yueee_yt 0:7766f6712673 200 if (odd && len > 0) {
yueee_yt 0:7766f6712673 201 ((u8_t *)&t)[1] = *pb++;
yueee_yt 0:7766f6712673 202 len--;
yueee_yt 0:7766f6712673 203 }
yueee_yt 0:7766f6712673 204
yueee_yt 0:7766f6712673 205 ps = (u16_t *)pb;
yueee_yt 0:7766f6712673 206
yueee_yt 0:7766f6712673 207 if (((mem_ptr_t)ps & 3) && len > 1) {
yueee_yt 0:7766f6712673 208 sum += *ps++;
yueee_yt 0:7766f6712673 209 len -= 2;
yueee_yt 0:7766f6712673 210 }
yueee_yt 0:7766f6712673 211
yueee_yt 0:7766f6712673 212 pl = (u32_t *)ps;
yueee_yt 0:7766f6712673 213
yueee_yt 0:7766f6712673 214 while (len > 7) {
yueee_yt 0:7766f6712673 215 tmp = sum + *pl++; /* ping */
yueee_yt 0:7766f6712673 216 if (tmp < sum) {
yueee_yt 0:7766f6712673 217 tmp++; /* add back carry */
yueee_yt 0:7766f6712673 218 }
yueee_yt 0:7766f6712673 219
yueee_yt 0:7766f6712673 220 sum = tmp + *pl++; /* pong */
yueee_yt 0:7766f6712673 221 if (sum < tmp) {
yueee_yt 0:7766f6712673 222 sum++; /* add back carry */
yueee_yt 0:7766f6712673 223 }
yueee_yt 0:7766f6712673 224
yueee_yt 0:7766f6712673 225 len -= 8;
yueee_yt 0:7766f6712673 226 }
yueee_yt 0:7766f6712673 227
yueee_yt 0:7766f6712673 228 /* make room in upper bits */
yueee_yt 0:7766f6712673 229 sum = FOLD_U32T(sum);
yueee_yt 0:7766f6712673 230
yueee_yt 0:7766f6712673 231 ps = (u16_t *)pl;
yueee_yt 0:7766f6712673 232
yueee_yt 0:7766f6712673 233 /* 16-bit aligned word remaining? */
yueee_yt 0:7766f6712673 234 while (len > 1) {
yueee_yt 0:7766f6712673 235 sum += *ps++;
yueee_yt 0:7766f6712673 236 len -= 2;
yueee_yt 0:7766f6712673 237 }
yueee_yt 0:7766f6712673 238
yueee_yt 0:7766f6712673 239 /* dangling tail byte remaining? */
yueee_yt 0:7766f6712673 240 if (len > 0) { /* include odd byte */
yueee_yt 0:7766f6712673 241 ((u8_t *)&t)[0] = *(u8_t *)ps;
yueee_yt 0:7766f6712673 242 }
yueee_yt 0:7766f6712673 243
yueee_yt 0:7766f6712673 244 sum += t; /* add end bytes */
yueee_yt 0:7766f6712673 245
yueee_yt 0:7766f6712673 246 /* Fold 32-bit sum to 16 bits
yueee_yt 0:7766f6712673 247 calling this twice is propably faster than if statements... */
yueee_yt 0:7766f6712673 248 sum = FOLD_U32T(sum);
yueee_yt 0:7766f6712673 249 sum = FOLD_U32T(sum);
yueee_yt 0:7766f6712673 250
yueee_yt 0:7766f6712673 251 if (odd) {
yueee_yt 0:7766f6712673 252 sum = SWAP_BYTES_IN_WORD(sum);
yueee_yt 0:7766f6712673 253 }
yueee_yt 0:7766f6712673 254
yueee_yt 0:7766f6712673 255 return (u16_t)sum;
yueee_yt 0:7766f6712673 256 }
yueee_yt 0:7766f6712673 257 #endif
yueee_yt 0:7766f6712673 258
yueee_yt 0:7766f6712673 259 /* inet_chksum_pseudo:
yueee_yt 0:7766f6712673 260 *
yueee_yt 0:7766f6712673 261 * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
yueee_yt 0:7766f6712673 262 * IP addresses are expected to be in network byte order.
yueee_yt 0:7766f6712673 263 *
yueee_yt 0:7766f6712673 264 * @param p chain of pbufs over that a checksum should be calculated (ip data part)
yueee_yt 0:7766f6712673 265 * @param src source ip address (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 266 * @param dst destination ip address (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 267 * @param proto ip protocol (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 268 * @param proto_len length of the ip data part (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 269 * @return checksum (as u16_t) to be saved directly in the protocol header
yueee_yt 0:7766f6712673 270 */
yueee_yt 0:7766f6712673 271 u16_t
yueee_yt 0:7766f6712673 272 inet_chksum_pseudo(struct pbuf *p,
yueee_yt 0:7766f6712673 273 ip_addr_t *src, ip_addr_t *dest,
yueee_yt 0:7766f6712673 274 u8_t proto, u16_t proto_len)
yueee_yt 0:7766f6712673 275 {
yueee_yt 0:7766f6712673 276 u32_t acc;
yueee_yt 0:7766f6712673 277 u32_t addr;
yueee_yt 0:7766f6712673 278 struct pbuf *q;
yueee_yt 0:7766f6712673 279 u8_t swapped;
yueee_yt 0:7766f6712673 280
yueee_yt 0:7766f6712673 281 acc = 0;
yueee_yt 0:7766f6712673 282 swapped = 0;
yueee_yt 0:7766f6712673 283 /* iterate through all pbuf in chain */
yueee_yt 0:7766f6712673 284 for(q = p; q != NULL; q = q->next) {
yueee_yt 0:7766f6712673 285 LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
yueee_yt 0:7766f6712673 286 (void *)q, (void *)q->next));
yueee_yt 0:7766f6712673 287 acc += LWIP_CHKSUM(q->payload, q->len);
yueee_yt 0:7766f6712673 288 /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
yueee_yt 0:7766f6712673 289 /* just executing this next line is probably faster that the if statement needed
yueee_yt 0:7766f6712673 290 to check whether we really need to execute it, and does no harm */
yueee_yt 0:7766f6712673 291 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 292 if (q->len % 2 != 0) {
yueee_yt 0:7766f6712673 293 swapped = 1 - swapped;
yueee_yt 0:7766f6712673 294 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 295 }
yueee_yt 0:7766f6712673 296 /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
yueee_yt 0:7766f6712673 297 }
yueee_yt 0:7766f6712673 298
yueee_yt 0:7766f6712673 299 if (swapped) {
yueee_yt 0:7766f6712673 300 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 301 }
yueee_yt 0:7766f6712673 302 addr = ip4_addr_get_u32(src);
yueee_yt 0:7766f6712673 303 acc += (addr & 0xffffUL);
yueee_yt 0:7766f6712673 304 acc += ((addr >> 16) & 0xffffUL);
yueee_yt 0:7766f6712673 305 addr = ip4_addr_get_u32(dest);
yueee_yt 0:7766f6712673 306 acc += (addr & 0xffffUL);
yueee_yt 0:7766f6712673 307 acc += ((addr >> 16) & 0xffffUL);
yueee_yt 0:7766f6712673 308 acc += (u32_t)htons((u16_t)proto);
yueee_yt 0:7766f6712673 309 acc += (u32_t)htons(proto_len);
yueee_yt 0:7766f6712673 310
yueee_yt 0:7766f6712673 311 /* Fold 32-bit sum to 16 bits
yueee_yt 0:7766f6712673 312 calling this twice is propably faster than if statements... */
yueee_yt 0:7766f6712673 313 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 314 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 315 LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
yueee_yt 0:7766f6712673 316 return (u16_t)~(acc & 0xffffUL);
yueee_yt 0:7766f6712673 317 }
yueee_yt 0:7766f6712673 318
yueee_yt 0:7766f6712673 319 /* inet_chksum_pseudo:
yueee_yt 0:7766f6712673 320 *
yueee_yt 0:7766f6712673 321 * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
yueee_yt 0:7766f6712673 322 * IP addresses are expected to be in network byte order.
yueee_yt 0:7766f6712673 323 *
yueee_yt 0:7766f6712673 324 * @param p chain of pbufs over that a checksum should be calculated (ip data part)
yueee_yt 0:7766f6712673 325 * @param src source ip address (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 326 * @param dst destination ip address (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 327 * @param proto ip protocol (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 328 * @param proto_len length of the ip data part (used for checksum of pseudo header)
yueee_yt 0:7766f6712673 329 * @return checksum (as u16_t) to be saved directly in the protocol header
yueee_yt 0:7766f6712673 330 */
yueee_yt 0:7766f6712673 331 u16_t
yueee_yt 0:7766f6712673 332 inet_chksum_pseudo_partial(struct pbuf *p,
yueee_yt 0:7766f6712673 333 ip_addr_t *src, ip_addr_t *dest,
yueee_yt 0:7766f6712673 334 u8_t proto, u16_t proto_len, u16_t chksum_len)
yueee_yt 0:7766f6712673 335 {
yueee_yt 0:7766f6712673 336 u32_t acc;
yueee_yt 0:7766f6712673 337 u32_t addr;
yueee_yt 0:7766f6712673 338 struct pbuf *q;
yueee_yt 0:7766f6712673 339 u8_t swapped;
yueee_yt 0:7766f6712673 340 u16_t chklen;
yueee_yt 0:7766f6712673 341
yueee_yt 0:7766f6712673 342 acc = 0;
yueee_yt 0:7766f6712673 343 swapped = 0;
yueee_yt 0:7766f6712673 344 /* iterate through all pbuf in chain */
yueee_yt 0:7766f6712673 345 for(q = p; (q != NULL) && (chksum_len > 0); q = q->next) {
yueee_yt 0:7766f6712673 346 LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): checksumming pbuf %p (has next %p) \n",
yueee_yt 0:7766f6712673 347 (void *)q, (void *)q->next));
yueee_yt 0:7766f6712673 348 chklen = q->len;
yueee_yt 0:7766f6712673 349 if (chklen > chksum_len) {
yueee_yt 0:7766f6712673 350 chklen = chksum_len;
yueee_yt 0:7766f6712673 351 }
yueee_yt 0:7766f6712673 352 acc += LWIP_CHKSUM(q->payload, chklen);
yueee_yt 0:7766f6712673 353 chksum_len -= chklen;
yueee_yt 0:7766f6712673 354 LWIP_ASSERT("delete me", chksum_len < 0x7fff);
yueee_yt 0:7766f6712673 355 /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): unwrapped lwip_chksum()=%"X32_F" \n", acc));*/
yueee_yt 0:7766f6712673 356 /* fold the upper bit down */
yueee_yt 0:7766f6712673 357 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 358 if (q->len % 2 != 0) {
yueee_yt 0:7766f6712673 359 swapped = 1 - swapped;
yueee_yt 0:7766f6712673 360 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 361 }
yueee_yt 0:7766f6712673 362 /*LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): wrapped lwip_chksum()=%"X32_F" \n", acc));*/
yueee_yt 0:7766f6712673 363 }
yueee_yt 0:7766f6712673 364
yueee_yt 0:7766f6712673 365 if (swapped) {
yueee_yt 0:7766f6712673 366 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 367 }
yueee_yt 0:7766f6712673 368 addr = ip4_addr_get_u32(src);
yueee_yt 0:7766f6712673 369 acc += (addr & 0xffffUL);
yueee_yt 0:7766f6712673 370 acc += ((addr >> 16) & 0xffffUL);
yueee_yt 0:7766f6712673 371 addr = ip4_addr_get_u32(dest);
yueee_yt 0:7766f6712673 372 acc += (addr & 0xffffUL);
yueee_yt 0:7766f6712673 373 acc += ((addr >> 16) & 0xffffUL);
yueee_yt 0:7766f6712673 374 acc += (u32_t)htons((u16_t)proto);
yueee_yt 0:7766f6712673 375 acc += (u32_t)htons(proto_len);
yueee_yt 0:7766f6712673 376
yueee_yt 0:7766f6712673 377 /* Fold 32-bit sum to 16 bits
yueee_yt 0:7766f6712673 378 calling this twice is propably faster than if statements... */
yueee_yt 0:7766f6712673 379 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 380 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 381 LWIP_DEBUGF(INET_DEBUG, ("inet_chksum_pseudo(): pbuf chain lwip_chksum()=%"X32_F"\n", acc));
yueee_yt 0:7766f6712673 382 return (u16_t)~(acc & 0xffffUL);
yueee_yt 0:7766f6712673 383 }
yueee_yt 0:7766f6712673 384
yueee_yt 0:7766f6712673 385 /* inet_chksum:
yueee_yt 0:7766f6712673 386 *
yueee_yt 0:7766f6712673 387 * Calculates the Internet checksum over a portion of memory. Used primarily for IP
yueee_yt 0:7766f6712673 388 * and ICMP.
yueee_yt 0:7766f6712673 389 *
yueee_yt 0:7766f6712673 390 * @param dataptr start of the buffer to calculate the checksum (no alignment needed)
yueee_yt 0:7766f6712673 391 * @param len length of the buffer to calculate the checksum
yueee_yt 0:7766f6712673 392 * @return checksum (as u16_t) to be saved directly in the protocol header
yueee_yt 0:7766f6712673 393 */
yueee_yt 0:7766f6712673 394
yueee_yt 0:7766f6712673 395 u16_t
yueee_yt 0:7766f6712673 396 inet_chksum(void *dataptr, u16_t len)
yueee_yt 0:7766f6712673 397 {
yueee_yt 0:7766f6712673 398 return ~LWIP_CHKSUM(dataptr, len);
yueee_yt 0:7766f6712673 399 }
yueee_yt 0:7766f6712673 400
yueee_yt 0:7766f6712673 401 /**
yueee_yt 0:7766f6712673 402 * Calculate a checksum over a chain of pbufs (without pseudo-header, much like
yueee_yt 0:7766f6712673 403 * inet_chksum only pbufs are used).
yueee_yt 0:7766f6712673 404 *
yueee_yt 0:7766f6712673 405 * @param p pbuf chain over that the checksum should be calculated
yueee_yt 0:7766f6712673 406 * @return checksum (as u16_t) to be saved directly in the protocol header
yueee_yt 0:7766f6712673 407 */
yueee_yt 0:7766f6712673 408 u16_t
yueee_yt 0:7766f6712673 409 inet_chksum_pbuf(struct pbuf *p)
yueee_yt 0:7766f6712673 410 {
yueee_yt 0:7766f6712673 411 u32_t acc;
yueee_yt 0:7766f6712673 412 struct pbuf *q;
yueee_yt 0:7766f6712673 413 u8_t swapped;
yueee_yt 0:7766f6712673 414
yueee_yt 0:7766f6712673 415 acc = 0;
yueee_yt 0:7766f6712673 416 swapped = 0;
yueee_yt 0:7766f6712673 417 for(q = p; q != NULL; q = q->next) {
yueee_yt 0:7766f6712673 418 acc += LWIP_CHKSUM(q->payload, q->len);
yueee_yt 0:7766f6712673 419 acc = FOLD_U32T(acc);
yueee_yt 0:7766f6712673 420 if (q->len % 2 != 0) {
yueee_yt 0:7766f6712673 421 swapped = 1 - swapped;
yueee_yt 0:7766f6712673 422 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 423 }
yueee_yt 0:7766f6712673 424 }
yueee_yt 0:7766f6712673 425
yueee_yt 0:7766f6712673 426 if (swapped) {
yueee_yt 0:7766f6712673 427 acc = SWAP_BYTES_IN_WORD(acc);
yueee_yt 0:7766f6712673 428 }
yueee_yt 0:7766f6712673 429 return (u16_t)~(acc & 0xffffUL);
yueee_yt 0:7766f6712673 430 }
yueee_yt 0:7766f6712673 431
yueee_yt 0:7766f6712673 432 /* These are some implementations for LWIP_CHKSUM_COPY, which copies data
yueee_yt 0:7766f6712673 433 * like MEMCPY but generates a checksum at the same time. Since this is a
yueee_yt 0:7766f6712673 434 * performance-sensitive function, you might want to create your own version
yueee_yt 0:7766f6712673 435 * in assembly targeted at your hardware by defining it in lwipopts.h:
yueee_yt 0:7766f6712673 436 * #define LWIP_CHKSUM_COPY(dst, src, len) your_chksum_copy(dst, src, len)
yueee_yt 0:7766f6712673 437 */
yueee_yt 0:7766f6712673 438
yueee_yt 0:7766f6712673 439 #if (LWIP_CHKSUM_COPY_ALGORITHM == 1) /* Version #1 */
yueee_yt 0:7766f6712673 440 /** Safe but slow: first call MEMCPY, then call LWIP_CHKSUM.
yueee_yt 0:7766f6712673 441 * For architectures with big caches, data might still be in cache when
yueee_yt 0:7766f6712673 442 * generating the checksum after copying.
yueee_yt 0:7766f6712673 443 */
yueee_yt 0:7766f6712673 444 u16_t
yueee_yt 0:7766f6712673 445 lwip_chksum_copy(void *dst, const void *src, u16_t len)
yueee_yt 0:7766f6712673 446 {
yueee_yt 0:7766f6712673 447 MEMCPY(dst, src, len);
yueee_yt 0:7766f6712673 448 return LWIP_CHKSUM(dst, len);
yueee_yt 0:7766f6712673 449 }
yueee_yt 0:7766f6712673 450 #endif /* (LWIP_CHKSUM_COPY_ALGORITHM == 1) */