236 lines
		
	
	
	
		
			5.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			236 lines
		
	
	
	
		
			5.5 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | #ifndef _ASM_SCORE_CHECKSUM_H
 | ||
|  | #define _ASM_SCORE_CHECKSUM_H
 | ||
|  | 
 | ||
|  | #include <linux/in6.h>
 | ||
|  | #include <asm/uaccess.h>
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * computes the checksum of a memory block at buff, length len, | ||
|  |  * and adds in "sum" (32-bit) | ||
|  |  * | ||
|  |  * returns a 32-bit number suitable for feeding into itself | ||
|  |  * or csum_tcpudp_magic | ||
|  |  * | ||
|  |  * this function must be called with even lengths, except | ||
|  |  * for the last fragment, which may be odd | ||
|  |  * | ||
|  |  * it's best to have buff aligned on a 32-bit boundary | ||
|  |  */ | ||
|  | unsigned int csum_partial(const void *buff, int len, __wsum sum); | ||
|  | unsigned int csum_partial_copy_from_user(const char *src, char *dst, int len, | ||
|  | 					unsigned int sum, int *csum_err); | ||
|  | unsigned int csum_partial_copy(const char *src, char *dst, | ||
|  | 					int len, unsigned int sum); | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * this is a new version of the above that records errors it finds in *errp, | ||
|  |  * but continues and zeros the rest of the buffer. | ||
|  |  */ | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Copy and checksum to user | ||
|  |  */ | ||
|  | #define HAVE_CSUM_COPY_USER
 | ||
|  | static inline | ||
|  | __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len, | ||
|  | 			__wsum sum, int *err_ptr) | ||
|  | { | ||
|  | 	sum = csum_partial(src, len, sum); | ||
|  | 	if (copy_to_user(dst, src, len)) { | ||
|  | 		*err_ptr = -EFAULT; | ||
|  | 		return (__force __wsum) -1; /* invalid checksum */ | ||
|  | 	} | ||
|  | 	return sum; | ||
|  | } | ||
|  | 
 | ||
|  | 
 | ||
|  | #define csum_partial_copy_nocheck csum_partial_copy
 | ||
|  | /*
 | ||
|  |  *	Fold a partial checksum without adding pseudo headers | ||
|  |  */ | ||
|  | 
 | ||
|  | static inline __sum16 csum_fold(__wsum sum) | ||
|  | { | ||
|  | 	/* the while loop is unnecessary really, it's always enough with two
 | ||
|  | 	   iterations */ | ||
|  | 	__asm__ __volatile__( | ||
|  | 		".set volatile\n\t" | ||
|  | 		".set\tr1\n\t" | ||
|  | 		"slli\tr1,%0, 16\n\t" | ||
|  | 		"add\t%0,%0, r1\n\t" | ||
|  | 		"cmp.c\tr1, %0\n\t" | ||
|  | 		"srli\t%0, %0, 16\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:ldi\tr30, 0xffff\n\t" | ||
|  | 		"xor\t%0, %0, r30\n\t" | ||
|  | 		"slli\t%0, %0, 16\n\t" | ||
|  | 		"srli\t%0, %0, 16\n\t" | ||
|  | 		".set\tnor1\n\t" | ||
|  | 		".set optimize\n\t" | ||
|  | 		: "=r" (sum) | ||
|  | 		: "0" (sum)); | ||
|  | 	return sum; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  *	This is a version of ip_compute_csum() optimized for IP headers, | ||
|  |  *	which always checksum on 4 octet boundaries. | ||
|  |  * | ||
|  |  *	By Jorge Cwik <jorge@laser.satlink.net>, adapted for linux by | ||
|  |  *	Arnt Gulbrandsen. | ||
|  |  */ | ||
|  | static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) | ||
|  | { | ||
|  | 	unsigned int sum; | ||
|  | 	unsigned long dummy; | ||
|  | 
 | ||
|  | 	__asm__ __volatile__( | ||
|  | 		".set volatile\n\t" | ||
|  | 		".set\tnor1\n\t" | ||
|  | 		"lw\t%0, [%1]\n\t" | ||
|  | 		"subri\t%2, %2, 4\n\t" | ||
|  | 		"slli\t%2, %2, 2\n\t" | ||
|  | 		"lw\t%3, [%1, 4]\n\t" | ||
|  | 		"add\t%2, %2, %1\n\t" | ||
|  | 		"add\t%0, %0, %3\n\t" | ||
|  | 		"cmp.c\t%3, %0\n\t" | ||
|  | 		"lw\t%3, [%1, 8]\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:\n\t" | ||
|  | 		"add\t%0, %0, %3\n\t" | ||
|  | 		"cmp.c\t%3, %0\n\t" | ||
|  | 		"lw\t%3, [%1, 12]\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:add\t%0, %0, %3\n\t" | ||
|  | 		"cmp.c\t%3, %0\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n" | ||
|  | 
 | ||
|  | 		"1:\tlw\t%3, [%1, 16]\n\t" | ||
|  | 		"addi\t%1, 4\n\t" | ||
|  | 		"add\t%0, %0, %3\n\t" | ||
|  | 		"cmp.c\t%3, %0\n\t" | ||
|  | 		"bleu\t2f\n\t" | ||
|  | 		"addi\t%0, 0x1\n" | ||
|  | 		"2:cmp.c\t%2, %1\n\t" | ||
|  | 		"bne\t1b\n\t" | ||
|  | 
 | ||
|  | 		".set\tr1\n\t" | ||
|  | 		".set optimize\n\t" | ||
|  | 		: "=&r" (sum), "=&r" (iph), "=&r" (ihl), "=&r" (dummy) | ||
|  | 		: "1" (iph), "2" (ihl)); | ||
|  | 
 | ||
|  | 	return csum_fold(sum); | ||
|  | } | ||
|  | 
 | ||
|  | static inline __wsum | ||
|  | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, | ||
|  | 		unsigned short proto, __wsum sum) | ||
|  | { | ||
|  | 	unsigned long tmp = (ntohs(len) << 16) + proto * 256; | ||
|  | 	__asm__ __volatile__( | ||
|  | 		".set volatile\n\t" | ||
|  | 		"add\t%0, %0, %2\n\t" | ||
|  | 		"cmp.c\t%2, %0\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:\n\t" | ||
|  | 		"add\t%0, %0, %3\n\t" | ||
|  | 		"cmp.c\t%3, %0\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:\n\t" | ||
|  | 		"add\t%0, %0, %4\n\t" | ||
|  | 		"cmp.c\t%4, %0\n\t" | ||
|  | 		"bleu\t1f\n\t" | ||
|  | 		"addi\t%0, 0x1\n\t" | ||
|  | 		"1:\n\t" | ||
|  | 		".set optimize\n\t" | ||
|  | 		: "=r" (sum) | ||
|  | 		: "0" (daddr), "r"(saddr), | ||
|  | 		"r" (tmp), | ||
|  | 		"r" (sum)); | ||
|  | 	return sum; | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * computes the checksum of the TCP/UDP pseudo-header | ||
|  |  * returns a 16-bit checksum, already complemented | ||
|  |  */ | ||
|  | static inline __sum16 | ||
|  | csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len, | ||
|  | 		unsigned short proto, __wsum sum) | ||
|  | { | ||
|  | 	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * this routine is used for miscellaneous IP-like checksums, mainly | ||
|  |  * in icmp.c | ||
|  |  */ | ||
|  | 
 | ||
|  | static inline unsigned short ip_compute_csum(const void *buff, int len) | ||
|  | { | ||
|  | 	return csum_fold(csum_partial(buff, len, 0)); | ||
|  | } | ||
|  | 
 | ||
|  | #define _HAVE_ARCH_IPV6_CSUM
 | ||
|  | static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, | ||
|  | 				const struct in6_addr *daddr, | ||
|  | 				__u32 len, unsigned short proto, | ||
|  | 				__wsum sum) | ||
|  | { | ||
|  | 	__asm__ __volatile__( | ||
|  | 		".set\tnoreorder\t\t\t# csum_ipv6_magic\n\t" | ||
|  | 		".set\tnoat\n\t" | ||
|  | 		"addu\t%0, %5\t\t\t# proto (long in network byte order)\n\t" | ||
|  | 		"sltu\t$1, %0, %5\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %6\t\t\t# csum\n\t" | ||
|  | 		"sltu\t$1, %0, %6\n\t" | ||
|  | 		"lw\t%1, 0(%2)\t\t\t# four words source address\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 4(%2)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 8(%2)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 12(%2)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 0(%3)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 4(%3)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 8(%3)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"lw\t%1, 12(%3)\n\t" | ||
|  | 		"addu\t%0, $1\n\t" | ||
|  | 		"addu\t%0, %1\n\t" | ||
|  | 		"sltu\t$1, %0, %1\n\t" | ||
|  | 		"addu\t%0, $1\t\t\t# Add final carry\n\t" | ||
|  | 		".set\tnoat\n\t" | ||
|  | 		".set\tnoreorder" | ||
|  | 		: "=r" (sum), "=r" (proto) | ||
|  | 		: "r" (saddr), "r" (daddr), | ||
|  | 		  "0" (htonl(len)), "1" (htonl(proto)), "r" (sum)); | ||
|  | 
 | ||
|  | 	return csum_fold(sum); | ||
|  | } | ||
|  | #endif /* _ASM_SCORE_CHECKSUM_H */
 |