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	 b79a79471b
			
		
	
	
		b79a79471b
		
	
	
	
	
		
			
			This patch fixes hash collisions in cases where number of entries have incrementing IP source and destination addresses from single respective subnets (i.e. 192.168.0.1-172.16.0.1, 192.168.0.2-172.16.0.2, and so on.). Signed-off-by: Jussi Maki <joamaki@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			130 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			130 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _XFRM_HASH_H
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| #define _XFRM_HASH_H
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| 
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| #include <linux/xfrm.h>
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| #include <linux/socket.h>
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| 
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| static inline unsigned int __xfrm4_addr_hash(xfrm_address_t *addr)
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| {
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| 	return ntohl(addr->a4);
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| }
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| 
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| static inline unsigned int __xfrm6_addr_hash(xfrm_address_t *addr)
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| {
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| 	return ntohl(addr->a6[2] ^ addr->a6[3]);
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| }
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| 
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| static inline unsigned int __xfrm4_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
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| {
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| 	return ntohl(daddr->a4 + saddr->a4);
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| }
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| 
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| static inline unsigned int __xfrm6_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
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| {
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| 	return ntohl(daddr->a6[2] ^ daddr->a6[3] ^
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| 		     saddr->a6[2] ^ saddr->a6[3]);
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| }
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| 
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| static inline unsigned int __xfrm_dst_hash(xfrm_address_t *daddr, xfrm_address_t *saddr,
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| 					   u32 reqid, unsigned short family,
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| 					   unsigned int hmask)
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| {
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| 	unsigned int h = family ^ reqid;
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| 	switch (family) {
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| 	case AF_INET:
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| 		h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	case AF_INET6:
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| 		h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	}
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| 	return (h ^ (h >> 16)) & hmask;
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| }
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| 
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| static inline unsigned __xfrm_src_hash(xfrm_address_t *daddr,
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| 				       xfrm_address_t *saddr,
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| 				       unsigned short family,
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| 				       unsigned int hmask)
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| {
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| 	unsigned int h = family;
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| 	switch (family) {
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| 	case AF_INET:
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| 		h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	case AF_INET6:
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| 		h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	};
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| 	return (h ^ (h >> 16)) & hmask;
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| }
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| 
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| static inline unsigned int
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| __xfrm_spi_hash(xfrm_address_t *daddr, __be32 spi, u8 proto, unsigned short family,
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| 		unsigned int hmask)
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| {
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| 	unsigned int h = (__force u32)spi ^ proto;
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| 	switch (family) {
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| 	case AF_INET:
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| 		h ^= __xfrm4_addr_hash(daddr);
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| 		break;
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| 	case AF_INET6:
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| 		h ^= __xfrm6_addr_hash(daddr);
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| 		break;
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| 	}
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| 	return (h ^ (h >> 10) ^ (h >> 20)) & hmask;
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| }
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| 
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| static inline unsigned int __idx_hash(u32 index, unsigned int hmask)
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| {
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| 	return (index ^ (index >> 8)) & hmask;
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| }
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| 
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| static inline unsigned int __sel_hash(struct xfrm_selector *sel, unsigned short family, unsigned int hmask)
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| {
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| 	xfrm_address_t *daddr = &sel->daddr;
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| 	xfrm_address_t *saddr = &sel->saddr;
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| 	unsigned int h = 0;
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| 
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| 	switch (family) {
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| 	case AF_INET:
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| 		if (sel->prefixlen_d != 32 ||
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| 		    sel->prefixlen_s != 32)
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| 			return hmask + 1;
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| 
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| 		h = __xfrm4_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 
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| 	case AF_INET6:
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| 		if (sel->prefixlen_d != 128 ||
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| 		    sel->prefixlen_s != 128)
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| 			return hmask + 1;
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| 
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| 		h = __xfrm6_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	};
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| 	h ^= (h >> 16);
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| 	return h & hmask;
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| }
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| 
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| static inline unsigned int __addr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, unsigned int hmask)
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| {
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| 	unsigned int h = 0;
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| 
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| 	switch (family) {
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| 	case AF_INET:
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| 		h = __xfrm4_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 
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| 	case AF_INET6:
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| 		h = __xfrm6_daddr_saddr_hash(daddr, saddr);
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| 		break;
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| 	};
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| 	h ^= (h >> 16);
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| 	return h & hmask;
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| }
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| 
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| extern struct hlist_head *xfrm_hash_alloc(unsigned int sz);
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| extern void xfrm_hash_free(struct hlist_head *n, unsigned int sz);
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| 
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| #endif /* _XFRM_HASH_H */
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