hw/arm/virt-acpi-build: don't save VirtGuestInfo on AcpiBuildState
[qemu.git] / 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 #include "qemu/bswap.h"
22 struct iovec;
23
24 uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq);
25 uint16_t net_checksum_finish(uint32_t sum);
26 uint16_t net_checksum_tcpudp(uint16_t length, uint16_t proto,
27 uint8_t *addrs, uint8_t *buf);
28 void net_checksum_calculate(uint8_t *data, int length);
29
30 static inline uint32_t
31 net_checksum_add(int len, uint8_t *buf)
32 {
33 return net_checksum_add_cont(len, buf, 0);
34 }
35
36 static inline uint16_t
37 net_raw_checksum(uint8_t *data, int length)
38 {
39 return net_checksum_finish(net_checksum_add(length, data));
40 }
41
42 /**
43 * net_checksum_add_iov: scatter-gather vector checksumming
44 *
45 * @iov: input scatter-gather array
46 * @iov_cnt: number of array elements
47 * @iov_off: starting iov offset for checksumming
48 * @size: length of data to be checksummed
49 * @csum_offset: offset of the checksum chunk
50 */
51 uint32_t net_checksum_add_iov(const struct iovec *iov,
52 const unsigned int iov_cnt,
53 uint32_t iov_off, uint32_t size,
54 uint32_t csum_offset);
55
56 typedef struct toeplitz_key_st {
57 uint32_t leftmost_32_bits;
58 uint8_t *next_byte;
59 } net_toeplitz_key;
60
61 static inline
62 void net_toeplitz_key_init(net_toeplitz_key *key, uint8_t *key_bytes)
63 {
64 key->leftmost_32_bits = be32_to_cpu(*(uint32_t *)key_bytes);
65 key->next_byte = key_bytes + sizeof(uint32_t);
66 }
67
68 static inline
69 void net_toeplitz_add(uint32_t *result,
70 uint8_t *input,
71 uint32_t len,
72 net_toeplitz_key *key)
73 {
74 register uint32_t accumulator = *result;
75 register uint32_t leftmost_32_bits = key->leftmost_32_bits;
76 register uint32_t byte;
77
78 for (byte = 0; byte < len; byte++) {
79 register uint8_t input_byte = input[byte];
80 register uint8_t key_byte = *(key->next_byte++);
81 register uint8_t bit;
82
83 for (bit = 0; bit < 8; bit++) {
84 if (input_byte & (1 << 7)) {
85 accumulator ^= leftmost_32_bits;
86 }
87
88 leftmost_32_bits =
89 (leftmost_32_bits << 1) | ((key_byte & (1 << 7)) >> 7);
90
91 input_byte <<= 1;
92 key_byte <<= 1;
93 }
94 }
95
96 key->leftmost_32_bits = leftmost_32_bits;
97 *result = accumulator;
98 }
99
100 #endif /* QEMU_NET_CHECKSUM_H */