Linux C sha1 算法（内核态）

#include 
#include 
#include 
#include 
#include 
#include 

typedef unsigned int uint32;
typedef uint32 word32;
typedef struct {
    uint32 h[5];
    unsigned char block[64];
    int blkused;
    uint32 lenhi, lenlo;
} SHA_State;
void SHA_Init(SHA_State * s);
void SHA_Bytes(SHA_State * s, const void *p, int len);
void SHA_Final(SHA_State * s, unsigned char *output);
void SHA_Simple(const void *p, int len, unsigned char *output);

#include "sha.h"

#define rol(x,y) ( ((x) << (y)) | (((uint32)x) >> (32-y)) )
#define PUT_32BIT_MSB_FIRST(cp, value) ( 
  (cp)[0] = (unsigned char)((value) >> 24), 
  (cp)[1] = (unsigned char)((value) >> 16), 
  (cp)[2] = (unsigned char)((value) >> 8), 
  (cp)[3] = (unsigned char)(value) )

static voi