ReactOS  0.4.14-dev-384-g5b37caa
inet6.c
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1 
8 /*
9  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without modification,
13  * are permitted provided that the following conditions are met:
14  *
15  * 1. Redistributions of source code must retain the above copyright notice,
16  * this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright notice,
18  * this list of conditions and the following disclaimer in the documentation
19  * and/or other materials provided with the distribution.
20  * 3. The name of the author may not be used to endorse or promote products
21  * derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
26  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
27  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
28  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
31  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
32  * OF SUCH DAMAGE.
33  *
34  * This file is part of the lwIP TCP/IP stack.
35  *
36  * Author: Adam Dunkels <adam@sics.se>
37  *
38  */
39 
40 #include "lwip/opt.h"
41 
42 #include "lwip/def.h"
43 #include "lwip/inet.h"
44 
45 /* chksum:
46  *
47  * Sums up all 16 bit words in a memory portion. Also includes any odd byte.
48  * This function is used by the other checksum functions.
49  *
50  * For now, this is not optimized. Must be optimized for the particular processor
51  * arcitecture on which it is to run. Preferebly coded in assembler.
52  */
53 
54 static u32_t
56 {
57  u16_t *sdataptr = dataptr;
58  u32_t acc;
59 
60 
61  for(acc = 0; len > 1; len -= 2) {
62  acc += *sdataptr++;
63  }
64 
65  /* add up any odd byte */
66  if (len == 1) {
67  acc += htons((u16_t)(*(u8_t *)dataptr) << 8);
68  }
69 
70  return acc;
71 
72 }
73 
74 /* inet_chksum_pseudo:
75  *
76  * Calculates the pseudo Internet checksum used by TCP and UDP for a pbuf chain.
77  */
78 
79 u16_t
81  struct ip_addr *src, struct ip_addr *dest,
82  u8_t proto, u32_t proto_len)
83 {
84  u32_t acc;
85  struct pbuf *q;
86  u8_t swapped, i;
87 
88  acc = 0;
89  swapped = 0;
90  for(q = p; q != NULL; q = q->next) {
91  acc += chksum(q->payload, q->len);
92  while (acc >> 16) {
93  acc = (acc & 0xffff) + (acc >> 16);
94  }
95  if (q->len % 2 != 0) {
96  swapped = 1 - swapped;
97  acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
98  }
99  }
100 
101  if (swapped) {
102  acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
103  }
104 
105  for(i = 0; i < 8; i++) {
106  acc += ((u16_t *)src->addr)[i] & 0xffff;
107  acc += ((u16_t *)dest->addr)[i] & 0xffff;
108  while (acc >> 16) {
109  acc = (acc & 0xffff) + (acc >> 16);
110  }
111  }
112  acc += (u16_t)htons((u16_t)proto);
113  acc += ((u16_t *)&proto_len)[0] & 0xffff;
114  acc += ((u16_t *)&proto_len)[1] & 0xffff;
115 
116  while (acc >> 16) {
117  acc = (acc & 0xffff) + (acc >> 16);
118  }
119  return ~(acc & 0xffff);
120 }
121 
122 /* inet_chksum:
123  *
124  * Calculates the Internet checksum over a portion of memory. Used primarely for IP
125  * and ICMP.
126  */
127 
128 u16_t
130 {
131  u32_t acc, sum;
132 
133  acc = chksum(dataptr, len);
134  sum = (acc & 0xffff) + (acc >> 16);
135  sum += (sum >> 16);
136  return ~(sum & 0xffff);
137 }
138 
139 u16_t
141 {
142  u32_t acc;
143  struct pbuf *q;
144  u8_t swapped;
145 
146  acc = 0;
147  swapped = 0;
148  for(q = p; q != NULL; q = q->next) {
149  acc += chksum(q->payload, q->len);
150  while (acc >> 16) {
151  acc = (acc & 0xffff) + (acc >> 16);
152  }
153  if (q->len % 2 != 0) {
154  swapped = 1 - swapped;
155  acc = (acc & 0xff << 8) | (acc & 0xff00 >> 8);
156  }
157  }
158 
159  if (swapped) {
160  acc = ((acc & 0xff) << 8) | ((acc & 0xff00) >> 8);
161  }
162  return ~(acc & 0xffff);
163 }
u16_t inet_chksum(void *dataptr, u16_t len)
Definition: inet6.c:129
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
u16_t inet_chksum_pbuf(struct pbuf *p)
Definition: inet6.c:140
smooth NULL
Definition: ftsmooth.c:416
static int sum(int x_, int y_)
Definition: ptr2_test.cpp:35
Definition: pbuf.h:79
unsigned long u32_t
Definition: cc.h:25
GLdouble GLdouble GLdouble GLdouble q
Definition: gl.h:2063
GLenum GLsizei len
Definition: glext.h:6722
u16_t inet_chksum_pseudo(struct pbuf *p, struct ip_addr *src, struct ip_addr *dest, u8_t proto, u32_t proto_len)
Definition: inet6.c:80
GLenum src
Definition: glext.h:6340
static u32_t chksum(void *dataptr, u16_t len)
Definition: inet6.c:55
unsigned char u8_t
Definition: cc.h:23
int const JOCTET * dataptr
Definition: jpeglib.h:1027
static char * dest
Definition: rtl.c:135
unsigned short u16_t
Definition: cc.h:24
GLfloat GLfloat p
Definition: glext.h:8902
#define htons(x)
Definition: module.h:213