From fed85383ac34d82e96f227ce49ce68117cec23a0 Mon Sep 17 00:00:00 2001 From: YOSHIFUJI Hideaki Date: Fri, 11 Apr 2008 20:17:55 +0900 Subject: [IPV6]: Use XOR and OR rather than mutiple ands for ipv6 address comparisons. ipv6_addr_equal(), ipv6_addr_v4mapped(), ipv6_addr_is_ll_all_{nodes,routers}(), ipv6_masked_addr_cmp() Signed-off-by: YOSHIFUJI Hideaki --- include/net/addrconf.h | 14 ++++++-------- include/net/ipv6.h | 22 ++++++++++------------ 2 files changed, 16 insertions(+), 20 deletions(-) (limited to 'include') diff --git a/include/net/addrconf.h b/include/net/addrconf.h index bdcc863a60a..1dc9d03372d 100644 --- a/include/net/addrconf.h +++ b/include/net/addrconf.h @@ -240,18 +240,16 @@ static inline int ipv6_addr_is_multicast(const struct in6_addr *addr) static inline int ipv6_addr_is_ll_all_nodes(const struct in6_addr *addr) { - return (addr->s6_addr32[0] == htonl(0xff020000) && - addr->s6_addr32[1] == 0 && - addr->s6_addr32[2] == 0 && - addr->s6_addr32[3] == htonl(0x00000001)); + return (((addr->s6_addr32[0] ^ htonl(0xff020000)) | + addr->s6_addr32[1] | addr->s6_addr32[2] | + (addr->s6_addr32[3] ^ htonl(0x00000001))) == 0); } static inline int ipv6_addr_is_ll_all_routers(const struct in6_addr *addr) { - return (addr->s6_addr32[0] == htonl(0xff020000) && - addr->s6_addr32[1] == 0 && - addr->s6_addr32[2] == 0 && - addr->s6_addr32[3] == htonl(0x00000002)); + return (((addr->s6_addr32[0] ^ htonl(0xff020000)) | + addr->s6_addr32[1] | addr->s6_addr32[2] | + (addr->s6_addr32[3] ^ htonl(0x00000002))) == 0); } static inline int ipv6_isatap_eui64(u8 *eui, __be32 addr) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 5738c1c73ac..a0c285b6311 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -280,12 +280,10 @@ static inline int ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m, const struct in6_addr *a2) { - unsigned int i; - - for (i = 0; i < 4; i++) - if ((a1->s6_addr32[i] ^ a2->s6_addr32[i]) & m->s6_addr32[i]) - return 1; - return 0; + return (!!(((a1->s6_addr32[0] ^ a2->s6_addr32[0]) & m->s6_addr32[0]) | + ((a1->s6_addr32[1] ^ a2->s6_addr32[1]) & m->s6_addr32[1]) | + ((a1->s6_addr32[2] ^ a2->s6_addr32[2]) & m->s6_addr32[2]) | + ((a1->s6_addr32[3] ^ a2->s6_addr32[3]) & m->s6_addr32[3]))); } static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2) @@ -320,10 +318,10 @@ static inline void ipv6_addr_set(struct in6_addr *addr, static inline int ipv6_addr_equal(const struct in6_addr *a1, const struct in6_addr *a2) { - return (a1->s6_addr32[0] == a2->s6_addr32[0] && - a1->s6_addr32[1] == a2->s6_addr32[1] && - a1->s6_addr32[2] == a2->s6_addr32[2] && - a1->s6_addr32[3] == a2->s6_addr32[3]); + return (((a1->s6_addr32[0] ^ a2->s6_addr32[0]) | + (a1->s6_addr32[1] ^ a2->s6_addr32[1]) | + (a1->s6_addr32[2] ^ a2->s6_addr32[2]) | + (a1->s6_addr32[3] ^ a2->s6_addr32[3])) == 0); } static inline int __ipv6_prefix_equal(const __be32 *a1, const __be32 *a2, @@ -371,8 +369,8 @@ static inline int ipv6_addr_any(const struct in6_addr *a) static inline int ipv6_addr_v4mapped(const struct in6_addr *a) { - return ((a->s6_addr32[0] | a->s6_addr32[1]) == 0 && - a->s6_addr32[2] == htonl(0x0000ffff)); + return ((a->s6_addr32[0] | a->s6_addr32[1] | + (a->s6_addr32[2] ^ htonl(0x0000ffff))) == 0); } /* -- cgit v1.2.3