cksum.c

abstract rtos

#include "syscfg.h"

#ifdef __cplusplus
#if __cplusplus
extern "C"{
#endif 
#endif 

	
#include "aos.h"
	
	
#define NBBY			8                       
#define GA2S(x)         ((U32)(VOID *)(x))
	
#define ADDCARRY(x)  (x > 65535 ? x -= 65535 : x)
#define REDUCE {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);}
	
	struct iovec
	{
		S8	*iov_base;	
		S32	iov_len;	
	};
	
	U16
		inet_cksumv (struct iovec * v ,
		S32 nv ,
		U32 len)
	{
		S32 sum = 0;
		S32 vlen = 0;
		struct iovec *vp;
		S32 byte_swapped = 0;
		union {
			S8 c[2];
			U16 s;
		} s_util;
		union {
			U16 s[2];
			U32 l;
		} l_util;
		
		for (vp = v; nv && len; nv--, vp++) {
			union {
				S8 * c;
				U16 *s;
			} w;
			
			if (vp->iov_len == 0) {
				continue;
			}
			w.c = vp->iov_base;
			if (vlen == -1) {
				
				s_util.c[1] = *w.c;
				sum += s_util.s;
				w.c++;
				vlen = vp->iov_len - 1;
				len--;
			} else {
				vlen = vp->iov_len;
			}
			if ((S32)len < vlen) {
				vlen = (S32)len;
			}
			len -= (U32)vlen;
			
			if ((1 & GA2S(w.s)) && (vlen > 0)) {
				REDUCE;
				sum = (S32)((U32)sum << NBBY);
				s_util.c[0] = *w.c;
				w.c++;
				vlen--;
				byte_swapped = 1;
			}
			
			while ((vlen -= 32) >= 0) {
				sum += w.s[0];
				sum += w.s[1];
				sum += w.s[2];
				sum += w.s[3];
				sum += w.s[4];
				sum += w.s[5];
				sum += w.s[6];
				sum += w.s[7];
				sum += w.s[8];
				sum += w.s[9];
				sum += w.s[10];
				sum += w.s[11];
				sum += w.s[12];
				sum += w.s[13];
				sum += w.s[14];
				sum += w.s[15];
				w.s += 16;
			}
			vlen += 32;
			while ((vlen -= 8) >= 0) {
				sum += w.s[0];
				sum += w.s[1];
				sum += w.s[2];
				sum += w.s[3];
				w.s += 4;
			}
			vlen += 8;
			if (vlen == 0 && byte_swapped == 0) {
				continue;
			}
			REDUCE;
			while ((vlen -= 2) >= 0) {
				sum += *w.s++;
			}
			if (byte_swapped) {
				REDUCE;
				sum = (S32)((U32)sum << NBBY);
				byte_swapped = 0;
				if (vlen == -1) {
					s_util.c[1] = *w.c;
					sum += s_util.s;
					vlen = 0;
				} else {
					vlen = -1;
				}
			} else if (vlen == -1) {
				s_util.c[0] = *w.c;
			}
		}
		AOS_ASSERT(!len);
		if (vlen == -1) {
			
			s_util.c[1] = 0;
			sum += s_util.s;
		}
		REDUCE;
		return (U16)(~(U32)sum & 0xffff);
}


U16
INET_Cksum (VOID * cp ,
			U32 length)
{
    struct iovec iovec;
	
    iovec.iov_base = (S8 *) cp;
    iovec.iov_len = (S32) length;
	
    return inet_cksumv(&iovec, 1, length);
}


#ifdef	FLETCHER_CHECKSUM



#define	INLINE		8		
#define	INSHIFT		3		
#define	INLINEMASK	(INLINE - 1)	

#define	MAXITER		4096		
#define	ITERSHIFT	12		
#define	ITERMASK	(MAXITER - 1)	
#define	MAXINLINE	(MAXITER/INLINE)

#define	MODULUS		255		

U32
ISO_Cksum (VOID * pkt ,
		   U32 len ,
		   U8 * cksum)
{
    S32 c0, c1;
    U8 *cp;
    S32 n;
    S32 l;
	
    c0 = c1 = 0;
    cp = (U8 *) pkt;
    l = len;
	
    if (cksum) {
		*cksum = *(cksum + 1) = 0;
    }
	
    n = l & ITERMASK;
    switch (n & INLINEMASK) {
    case 7:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 6:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 5:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 4:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 3:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 2:
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		break;
    case 1:
		c1 += (c0 += (S32) (*cp++));
		break;
    case 0:
		break;
    }
	
    n >>= INSHIFT;
    while (n-- > 0) {
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
		c1 += (c0 += (S32) (*cp++));
    }
	
    n = l >> ITERSHIFT;
    if (n > 0) {
		do {
			S32 iter = MAXINLINE;
			
			if (cp != (U8 *) pkt) {
				c0 %= MODULUS;
				c1 %= MODULUS;
			}
			do {
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
				c1 += (c0 += (S32) (*cp++));
			} while (--iter > 0);
		} while (--n > 0);
    }
	
    c0 %= MODULUS;
    if (cksum) {
		
		c1 = (c1 - ((S32) (((U8 *) pkt + l) - cksum) * c0)) % MODULUS;
		if (c1 <= 0) {
			c1 += MODULUS;
		}
		
		c0 = MODULUS - c1 - c0;		
		if (c0 <= 0) {
			c0 += MODULUS;
		}
		*cksum++ = (U8) c0;
		*cksum = (U8) c1;
		
		return (U32) ((c0 << 8) | c1);
    }
	
    return (U32) (((c1 % MODULUS) << 8) | c0);
}

#endif 



#ifdef	MD5_CHECKSUM

#define	MD5_F(x, y, z)	(((~(x)) & (z)) | ((x) & (y)))
#define	MD5_G(x, y, z)	(((~(z)) & (y)) | ((z) & (x)))	
#define	MD5_H(x, y, z)	((x) ^ (y) ^ (z))
#define	MD5_I(x, y, z)	((y) ^ ((x) | (~(z))))

#ifndef	MD5_ROTL
#define	MD5_ROTL(x, s) \
((x) = ((x) << (s)) | (((x) >> (32 - (s))) & 0xffffffff))
#endif	

#define	MD5_OP1(a, b, c, d, xk, s, ti) \
    do { \
	(a) += MD5_F((b), (c), (d)) + (xk) + (ti); \
	MD5_ROTL((a), (s)); \
	(a) += (b); \
    } while (0)

#define	MD5_OP2(a, b, c, d, xk, s, ti) \
    do { \
	(a) += MD5_G((b), (c), (d)) + (xk) + (ti); \
	MD5_ROTL((a), (s)); \
	(a) += (b); \
    } while (0)

#define	MD5_OP3(a, b, c, d, xk, s, ti) \
    do { \
	(a) += MD5_H((b), (c), (d)) + (xk) + (ti); \
	MD5_ROTL((a), (s)); \
	(a) += (b); \
    } while (0)

#define	MD5_OP4(a, b, c, d, xk, s, ti) \
    do { \
	(a) += MD5_I((b), (c), (d)) + (xk) + (ti); \
	MD5_ROTL((a), (s)); \
	(a) += (b); \
    } while (0)


#define	MD5_A_INIT	0x67452301
#define	MD5_B_INIT	0xefcdab89
#define	MD5_C_INIT	0x98badcfe
#define	MD5_D_INIT	0x10325476

#define	MD5_GET(x, cp) \
    do { \
	U32 Xtmp; \
	Xtmp = (U32)(*(cp)++); \
	Xtmp |= ((U32)(*(cp)++)) << 8; \
	Xtmp |= ((U32)(*(cp)++)) << 16; \
	Xtmp |= ((U32)(*(cp)++)) << 24; \
	(x) = Xtmp; \
    } while (0)

#define	MD5_PUT(x, cp) \
    do { \
	U32 Xtmp = (x); \
	*(cp)++ = (U8) Xtmp; \
	*(cp)++ = (U8) (Xtmp >> 8); \
	*(cp)++ = (U8) (Xtmp >> 16); \
	*(cp)++ = (U8) (Xtmp >> 24); \
    } while (0)