include/net/checksum.h

   1 /*
   2  *  IP checksumming functions.
   3  *  (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; under version 2 of the License.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License
  15  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #ifndef QEMU_NET_CHECKSUM_H
  19 #define QEMU_NET_CHECKSUM_H
  20
  21 struct iovec;
  22
  23 uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq);
  24 uint16_t net_checksum_finish(uint32_t sum);
  25 uint16_t net_checksum_tcpudp(uint16_t length, uint16_t proto,
  26                              uint8_t *addrs, uint8_t *buf);
  27 void net_checksum_calculate(uint8_t *data, int length);
  28
  29 static inline uint32_t
  30 net_checksum_add(int len, uint8_t *buf)
  31 {
  32     return net_checksum_add_cont(len, buf, 0);
  33 }
  34
  35 static inline uint16_t
  36 net_raw_checksum(uint8_t *data, int length)
  37 {
  38     return net_checksum_finish(net_checksum_add(length, data));
  39 }
  40
  41 /**
  42  * net_checksum_add_iov: scatter-gather vector checksumming
  43  *
  44  * @iov: input scatter-gather array
  45  * @iov_cnt: number of array elements
  46  * @iov_off: starting iov offset for checksumming
  47  * @size: length of data to be checksummed
  48  */
  49 uint32_t net_checksum_add_iov(const struct iovec *iov,
  50                               const unsigned int iov_cnt,
  51                               uint32_t iov_off, uint32_t size);
  52
  53 #endif /* QEMU_NET_CHECKSUM_H */