lib/drivers/lwip/src/include/ipv4/lwip/inet_chksum.h

   1 /*
   2  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without modification,
   6  * are permitted provided that the following conditions are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright notice,
   9  *    this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright notice,
  11  *    this list of conditions and the following disclaimer in the documentation
  12  *    and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  19  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  21  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  25  * OF SUCH DAMAGE.
  26  *
  27  * This file is part of the lwIP TCP/IP stack.
  28  *
  29  * Author: Adam Dunkels <adam@sics.se>
  30  *
  31  */
  32 #ifndef __LWIP_INET_CHKSUM_H__
  33 #define __LWIP_INET_CHKSUM_H__
  34
  35 #include "lwip/opt.h"
  36
  37 #include "lwip/pbuf.h"
  38 #include "lwip/ip_addr.h"
  39
  40 /** Swap the bytes in an u16_t: much like htons() for little-endian */
  41 #ifndef SWAP_BYTES_IN_WORD
  42 #if LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN)
  43 /* little endian and PLATFORM_BYTESWAP defined */
  44 #define SWAP_BYTES_IN_WORD(w) LWIP_PLATFORM_HTONS(w)
  45 #else /* LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN) */
  46 /* can't use htons on big endian (or PLATFORM_BYTESWAP not defined)... */
  47 #define SWAP_BYTES_IN_WORD(w) (((w) & 0xff) << 8) | (((w) & 0xff00) >> 8)
  48 #endif /* LWIP_PLATFORM_BYTESWAP && (BYTE_ORDER == LITTLE_ENDIAN)*/
  49 #endif /* SWAP_BYTES_IN_WORD */
  50
  51 /** Split an u32_t in two u16_ts and add them up */
  52 #ifndef FOLD_U32T
  53 #define FOLD_U32T(u)          (((u) >> 16) + ((u) & 0x0000ffffUL))
  54 #endif
  55
  56 #if LWIP_CHECKSUM_ON_COPY
  57 /** Function-like macro: same as MEMCPY but returns the checksum of copied data
  58     as u16_t */
  59 #ifndef LWIP_CHKSUM_COPY
  60 #define LWIP_CHKSUM_COPY(dst, src, len) lwip_chksum_copy(dst, src, len)
  61 #ifndef LWIP_CHKSUM_COPY_ALGORITHM
  62 #define LWIP_CHKSUM_COPY_ALGORITHM 1
  63 #endif /* LWIP_CHKSUM_COPY_ALGORITHM */
  64 #endif /* LWIP_CHKSUM_COPY */
  65 #else /* LWIP_CHECKSUM_ON_COPY */
  66 #define LWIP_CHKSUM_COPY_ALGORITHM 0
  67 #endif /* LWIP_CHECKSUM_ON_COPY */
  68
  69 #ifdef __cplusplus
  70 extern "C" {
  71 #endif
  72
  73 u16_t inet_chksum(void *dataptr, u16_t len);
  74 u16_t inet_chksum_pbuf(struct pbuf *p);
  75 u16_t inet_chksum_pseudo(struct pbuf *p,
  76        ip_addr_t *src, ip_addr_t *dest,
  77        u8_t proto, u16_t proto_len);
  78 u16_t inet_chksum_pseudo_partial(struct pbuf *p,
  79        ip_addr_t *src, ip_addr_t *dest,
  80        u8_t proto, u16_t proto_len, u16_t chksum_len);
  81 #if LWIP_CHKSUM_COPY_ALGORITHM
  82 u16_t lwip_chksum_copy(void *dst, const void *src, u16_t len);
  83 #endif /* LWIP_CHKSUM_COPY_ALGORITHM */
  84
  85 #ifdef __cplusplus
  86 }
  87 #endif
  88
  89 #endif /* __LWIP_INET_H__ */
  90