diff options
Diffstat (limited to 'net/ipv6/syncookies.c')
| -rw-r--r-- | net/ipv6/syncookies.c | 41 |
1 files changed, 19 insertions, 22 deletions
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index a4d49760bf43..895ff650db43 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -16,7 +16,7 @@ #include <linux/tcp.h> #include <linux/random.h> -#include <linux/cryptohash.h> +#include <linux/siphash.h> #include <linux/kernel.h> #include <net/ipv6.h> #include <net/tcp.h> @@ -24,7 +24,7 @@ #define COOKIEBITS 24 /* Upper bits store count */ #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1) -static u32 syncookie6_secret[2][16-4+SHA_DIGEST_WORDS] __read_mostly; +static siphash_key_t syncookie6_secret[2] __read_mostly; /* RFC 2460, Section 8.3: * [ipv6 tcp] MSS must be computed as the maximum packet size minus 60 [..] @@ -41,30 +41,27 @@ static __u16 const msstab[] = { 9000 - 60, }; -static DEFINE_PER_CPU(__u32 [16 + 5 + SHA_WORKSPACE_WORDS], ipv6_cookie_scratch); - -static u32 cookie_hash(const struct in6_addr *saddr, const struct in6_addr *daddr, +static u32 cookie_hash(const struct in6_addr *saddr, + const struct in6_addr *daddr, __be16 sport, __be16 dport, u32 count, int c) { - __u32 *tmp; + const struct { + struct in6_addr saddr; + struct in6_addr daddr; + u32 count; + __be16 sport; + __be16 dport; + } __aligned(SIPHASH_ALIGNMENT) combined = { + .saddr = *saddr, + .daddr = *daddr, + .count = count, + .sport = sport, + .dport = dport + }; net_get_random_once(syncookie6_secret, sizeof(syncookie6_secret)); - - tmp = this_cpu_ptr(ipv6_cookie_scratch); - - /* - * we have 320 bits of information to hash, copy in the remaining - * 192 bits required for sha_transform, from the syncookie6_secret - * and overwrite the digest with the secret - */ - memcpy(tmp + 10, syncookie6_secret[c], 44); - memcpy(tmp, saddr, 16); - memcpy(tmp + 4, daddr, 16); - tmp[8] = ((__force u32)sport << 16) + (__force u32)dport; - tmp[9] = count; - sha_transform(tmp + 16, (__u8 *)tmp, tmp + 16 + 5); - - return tmp[17]; + return siphash(&combined, offsetofend(typeof(combined), dport), + &syncookie6_secret[c]); } static __u32 secure_tcp_syn_cookie(const struct in6_addr *saddr, |