siphash.c 文件参考

#include "../../../include/lammp/secret.h"

siphash.c 的引用(Include)关系图:

浏览源代码.

宏定义
#define	SIPROUND

函数
uint64_t	lmmp_siphash24_ (mp_srcptr in, mp_size_t inlen, srckey128_t key)
	SipHash-2-4 函数（非标准处理任意字节流的 SipHash-2-4）
static uint64_t	rotl64 (uint64_t x, int b)

宏定义说明

SIPROUND

#define SIPROUND

值:

    do {                     \
        v0 += v1;            \
        v1 = rotl64(v1, 13); \
        v1 ^= v0;            \
        v0 = rotl64(v0, 32); \
        v2 += v3;            \
        v3 = rotl64(v3, 16); \
        v3 ^= v2;            \
        v0 += v3;            \
        v3 = rotl64(v3, 21); \
        v3 ^= v0;            \
        v2 += v1;            \
        v1 = rotl64(v1, 17); \
        v1 ^= v2;            \
        v2 = rotl64(v2, 32); \
    } while (0)

函数说明

lmmp_siphash24_()

uint64_t lmmp_siphash24_	(	mp_srcptr	in,
		mp_size_t	inlen,
		srckey128_t	key
	)

SipHash-2-4 函数（非标准处理任意字节流的 SipHash-2-4）

参数

in	输入数据，可以为 NULL
inlen	输入数据长度
key	128-bit 秘钥，可以为 NULL

警告

若 key 为 NULL，则使用全零秘钥

返回

64-bit hash 值

在文件 siphash.c 第 14 行定义.

                                                                         {
#define SIPROUND             \
    do {                     \
        v0 += v1;            \
        v1 = rotl64(v1, 13); \
        v1 ^= v0;            \
        v0 = rotl64(v0, 32); \
        v2 += v3;            \
        v3 = rotl64(v3, 16); \
        v3 ^= v2;            \
        v0 += v3;            \
        v3 = rotl64(v3, 21); \
        v3 ^= v0;            \
        v2 += v1;            \
        v1 = rotl64(v1, 17); \
        v1 ^= v2;            \
        v2 = rotl64(v2, 32); \
    } while (0)
 
    uint64_t k0;
    uint64_t k1;
    if (key == NULL) {
        k0 = 0;
        k1 = 0;
    } else {
        k0 = key[0];
        k1 = key[1];
    }
 
    uint64_t v0 = 0x736f6d6570736575ULL ^ k0;
    uint64_t v1 = 0x646f72616e646f6dULL ^ k1;
    uint64_t v2 = 0x6c7967656e657261ULL ^ k0;
    uint64_t v3 = 0x7465646279746573ULL ^ k1;
 
    const uint64_t* data = (const uint64_t*)in;
    const uint64_t* end = data + inlen;
 
    const uint64_t* limit = data + (inlen & ~3ULL);
 
    while (data < limit) {
        uint64_t m0 = data[0];
        uint64_t m1 = data[1];
        uint64_t m2 = data[2];
        uint64_t m3 = data[3];
        data += 4;
 
        v3 ^= m0;
        SIPROUND;
        SIPROUND;
        v0 ^= m0;
 
        v3 ^= m1;
        SIPROUND;
        SIPROUND;
        v0 ^= m1;
 
        v3 ^= m2;
        SIPROUND;
        SIPROUND;
        v0 ^= m2;
 
        v3 ^= m3;
        SIPROUND;
        SIPROUND;
        v0 ^= m3;
    }
 
    while (data < end) {
        uint64_t m = *data++;
        v3 ^= m;
        SIPROUND;
        SIPROUND;
        v0 ^= m;
    }
 
    uint64_t b = ((uint64_t)(inlen * LIMB_BYTES)) << 56;
    v3 ^= b;
    SIPROUND;
    SIPROUND;
    v0 ^= b;
 
    v2 ^= 0xff;
    SIPROUND;
    SIPROUND;
    SIPROUND;
    SIPROUND;
 
    return v0 ^ v1 ^ v2 ^ v3;
}

引用了 LIMB_BYTES, SIPROUND, v0, v1 , 以及 v2.

rotl64()

static uint64_t rotl64 ( uint64_t  x, int  b  )

inlinestatic

在文件 siphash.c 第 9 行定义.

                                                 {
    b &= 63;
    return (x << b) | (x >> (64 - b));
}