17200ac3cSMark McLoughlin /* 27200ac3cSMark McLoughlin * IP checksumming functions. 37200ac3cSMark McLoughlin * (c) 2008 Gerd Hoffmann <kraxel@redhat.com> 47200ac3cSMark McLoughlin * 57200ac3cSMark McLoughlin * This program is free software; you can redistribute it and/or modify 67200ac3cSMark McLoughlin * it under the terms of the GNU General Public License as published by 77200ac3cSMark McLoughlin * the Free Software Foundation; under version 2 of the License. 87200ac3cSMark McLoughlin * 97200ac3cSMark McLoughlin * This program is distributed in the hope that it will be useful, 107200ac3cSMark McLoughlin * but WITHOUT ANY WARRANTY; without even the implied warranty of 117200ac3cSMark McLoughlin * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 127200ac3cSMark McLoughlin * GNU General Public License for more details. 137200ac3cSMark McLoughlin * 147200ac3cSMark McLoughlin * You should have received a copy of the GNU General Public License 157200ac3cSMark McLoughlin * along with this program; if not, see <http://www.gnu.org/licenses/>. 167200ac3cSMark McLoughlin */ 177200ac3cSMark McLoughlin 187200ac3cSMark McLoughlin #ifndef QEMU_NET_CHECKSUM_H 197200ac3cSMark McLoughlin #define QEMU_NET_CHECKSUM_H 207200ac3cSMark McLoughlin 210478d1ddSDmitry Fleytman #include "qemu/bswap.h" 2226247179SMichael Tokarev struct iovec; 237200ac3cSMark McLoughlin 245acf5ea4SDmitry Fleytman uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq); 257200ac3cSMark McLoughlin uint16_t net_checksum_finish(uint32_t sum); 267200ac3cSMark McLoughlin uint16_t net_checksum_tcpudp(uint16_t length, uint16_t proto, 277200ac3cSMark McLoughlin uint8_t *addrs, uint8_t *buf); 287200ac3cSMark McLoughlin void net_checksum_calculate(uint8_t *data, int length); 297200ac3cSMark McLoughlin 305acf5ea4SDmitry Fleytman static inline uint32_t 315acf5ea4SDmitry Fleytman net_checksum_add(int len, uint8_t *buf) 325acf5ea4SDmitry Fleytman { 335acf5ea4SDmitry Fleytman return net_checksum_add_cont(len, buf, 0); 345acf5ea4SDmitry Fleytman } 355acf5ea4SDmitry Fleytman 365acf5ea4SDmitry Fleytman static inline uint16_t 37*0dacea92SEd Swierk net_checksum_finish_nozero(uint32_t sum) 38*0dacea92SEd Swierk { 39*0dacea92SEd Swierk return net_checksum_finish(sum) ?: 0xFFFF; 40*0dacea92SEd Swierk } 41*0dacea92SEd Swierk 42*0dacea92SEd Swierk static inline uint16_t 435acf5ea4SDmitry Fleytman net_raw_checksum(uint8_t *data, int length) 445acf5ea4SDmitry Fleytman { 455acf5ea4SDmitry Fleytman return net_checksum_finish(net_checksum_add(length, data)); 465acf5ea4SDmitry Fleytman } 475acf5ea4SDmitry Fleytman 4884026301SDmitry Fleytman /** 4984026301SDmitry Fleytman * net_checksum_add_iov: scatter-gather vector checksumming 5084026301SDmitry Fleytman * 5184026301SDmitry Fleytman * @iov: input scatter-gather array 5284026301SDmitry Fleytman * @iov_cnt: number of array elements 5384026301SDmitry Fleytman * @iov_off: starting iov offset for checksumming 5484026301SDmitry Fleytman * @size: length of data to be checksummed 55eb700029SDmitry Fleytman * @csum_offset: offset of the checksum chunk 5684026301SDmitry Fleytman */ 5784026301SDmitry Fleytman uint32_t net_checksum_add_iov(const struct iovec *iov, 5884026301SDmitry Fleytman const unsigned int iov_cnt, 59eb700029SDmitry Fleytman uint32_t iov_off, uint32_t size, 60eb700029SDmitry Fleytman uint32_t csum_offset); 6184026301SDmitry Fleytman 620478d1ddSDmitry Fleytman typedef struct toeplitz_key_st { 630478d1ddSDmitry Fleytman uint32_t leftmost_32_bits; 640478d1ddSDmitry Fleytman uint8_t *next_byte; 650478d1ddSDmitry Fleytman } net_toeplitz_key; 660478d1ddSDmitry Fleytman 670478d1ddSDmitry Fleytman static inline 680478d1ddSDmitry Fleytman void net_toeplitz_key_init(net_toeplitz_key *key, uint8_t *key_bytes) 690478d1ddSDmitry Fleytman { 700478d1ddSDmitry Fleytman key->leftmost_32_bits = be32_to_cpu(*(uint32_t *)key_bytes); 710478d1ddSDmitry Fleytman key->next_byte = key_bytes + sizeof(uint32_t); 720478d1ddSDmitry Fleytman } 730478d1ddSDmitry Fleytman 740478d1ddSDmitry Fleytman static inline 750478d1ddSDmitry Fleytman void net_toeplitz_add(uint32_t *result, 760478d1ddSDmitry Fleytman uint8_t *input, 770478d1ddSDmitry Fleytman uint32_t len, 780478d1ddSDmitry Fleytman net_toeplitz_key *key) 790478d1ddSDmitry Fleytman { 800478d1ddSDmitry Fleytman register uint32_t accumulator = *result; 810478d1ddSDmitry Fleytman register uint32_t leftmost_32_bits = key->leftmost_32_bits; 820478d1ddSDmitry Fleytman register uint32_t byte; 830478d1ddSDmitry Fleytman 840478d1ddSDmitry Fleytman for (byte = 0; byte < len; byte++) { 850478d1ddSDmitry Fleytman register uint8_t input_byte = input[byte]; 860478d1ddSDmitry Fleytman register uint8_t key_byte = *(key->next_byte++); 870478d1ddSDmitry Fleytman register uint8_t bit; 880478d1ddSDmitry Fleytman 890478d1ddSDmitry Fleytman for (bit = 0; bit < 8; bit++) { 900478d1ddSDmitry Fleytman if (input_byte & (1 << 7)) { 910478d1ddSDmitry Fleytman accumulator ^= leftmost_32_bits; 920478d1ddSDmitry Fleytman } 930478d1ddSDmitry Fleytman 940478d1ddSDmitry Fleytman leftmost_32_bits = 950478d1ddSDmitry Fleytman (leftmost_32_bits << 1) | ((key_byte & (1 << 7)) >> 7); 960478d1ddSDmitry Fleytman 970478d1ddSDmitry Fleytman input_byte <<= 1; 980478d1ddSDmitry Fleytman key_byte <<= 1; 990478d1ddSDmitry Fleytman } 1000478d1ddSDmitry Fleytman } 1010478d1ddSDmitry Fleytman 1020478d1ddSDmitry Fleytman key->leftmost_32_bits = leftmost_32_bits; 1030478d1ddSDmitry Fleytman *result = accumulator; 1040478d1ddSDmitry Fleytman } 1050478d1ddSDmitry Fleytman 1067200ac3cSMark McLoughlin #endif /* QEMU_NET_CHECKSUM_H */ 107