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18#ifndef QEMU_NET_CHECKSUM_H
19#define QEMU_NET_CHECKSUM_H
20
21#include "qemu/bswap.h"
22struct iovec;
23
24uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq);
25uint16_t net_checksum_finish(uint32_t sum);
26uint16_t net_checksum_tcpudp(uint16_t length, uint16_t proto,
27 uint8_t *addrs, uint8_t *buf);
28void net_checksum_calculate(uint8_t *data, int length);
29
30static inline uint32_t
31net_checksum_add(int len, uint8_t *buf)
32{
33 return net_checksum_add_cont(len, buf, 0);
34}
35
36static inline uint16_t
37net_raw_checksum(uint8_t *data, int length)
38{
39 return net_checksum_finish(net_checksum_add(length, data));
40}
41
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49
50
51uint32_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
56typedef struct toeplitz_key_st {
57 uint32_t leftmost_32_bits;
58 uint8_t *next_byte;
59} net_toeplitz_key;
60
61static inline
62void 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
68static inline
69void 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
101