98 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			98 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | #include <net/ip.h>
 | ||
|  | #include <net/udp.h>
 | ||
|  | #include <net/udplite.h>
 | ||
|  | #include <asm/checksum.h>
 | ||
|  | 
 | ||
|  | #ifndef _HAVE_ARCH_IPV6_CSUM
 | ||
|  | __sum16 csum_ipv6_magic(const struct in6_addr *saddr, | ||
|  | 			const struct in6_addr *daddr, | ||
|  | 			__u32 len, unsigned short proto, | ||
|  | 			__wsum csum) | ||
|  | { | ||
|  | 
 | ||
|  | 	int carry; | ||
|  | 	__u32 ulen; | ||
|  | 	__u32 uproto; | ||
|  | 	__u32 sum = (__force u32)csum; | ||
|  | 
 | ||
|  | 	sum += (__force u32)saddr->s6_addr32[0]; | ||
|  | 	carry = (sum < (__force u32)saddr->s6_addr32[0]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)saddr->s6_addr32[1]; | ||
|  | 	carry = (sum < (__force u32)saddr->s6_addr32[1]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)saddr->s6_addr32[2]; | ||
|  | 	carry = (sum < (__force u32)saddr->s6_addr32[2]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)saddr->s6_addr32[3]; | ||
|  | 	carry = (sum < (__force u32)saddr->s6_addr32[3]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)daddr->s6_addr32[0]; | ||
|  | 	carry = (sum < (__force u32)daddr->s6_addr32[0]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)daddr->s6_addr32[1]; | ||
|  | 	carry = (sum < (__force u32)daddr->s6_addr32[1]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)daddr->s6_addr32[2]; | ||
|  | 	carry = (sum < (__force u32)daddr->s6_addr32[2]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	sum += (__force u32)daddr->s6_addr32[3]; | ||
|  | 	carry = (sum < (__force u32)daddr->s6_addr32[3]); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	ulen = (__force u32)htonl((__u32) len); | ||
|  | 	sum += ulen; | ||
|  | 	carry = (sum < ulen); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	uproto = (__force u32)htonl(proto); | ||
|  | 	sum += uproto; | ||
|  | 	carry = (sum < uproto); | ||
|  | 	sum += carry; | ||
|  | 
 | ||
|  | 	return csum_fold((__force __wsum)sum); | ||
|  | } | ||
|  | EXPORT_SYMBOL(csum_ipv6_magic); | ||
|  | #endif
 | ||
|  | 
 | ||
|  | int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto) | ||
|  | { | ||
|  | 	int err; | ||
|  | 
 | ||
|  | 	UDP_SKB_CB(skb)->partial_cov = 0; | ||
|  | 	UDP_SKB_CB(skb)->cscov = skb->len; | ||
|  | 
 | ||
|  | 	if (proto == IPPROTO_UDPLITE) { | ||
|  | 		err = udplite_checksum_init(skb, uh); | ||
|  | 		if (err) | ||
|  | 			return err; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	if (uh->check == 0) { | ||
|  | 		/* RFC 2460 section 8.1 says that we SHOULD log
 | ||
|  | 		   this error. Well, it is reasonable. | ||
|  | 		 */ | ||
|  | 		LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n"); | ||
|  | 		return 1; | ||
|  | 	} | ||
|  | 	if (skb->ip_summed == CHECKSUM_COMPLETE && | ||
|  | 	    !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr, | ||
|  | 			     skb->len, proto, skb->csum)) | ||
|  | 		skb->ip_summed = CHECKSUM_UNNECESSARY; | ||
|  | 
 | ||
|  | 	if (!skb_csum_unnecessary(skb)) | ||
|  | 		skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, | ||
|  | 							 &ipv6_hdr(skb)->daddr, | ||
|  | 							 skb->len, proto, 0)); | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | EXPORT_SYMBOL(udp6_csum_init); |