diff options
Diffstat (limited to 'net/ipv6/syncookies.c')
| -rw-r--r-- | net/ipv6/syncookies.c | 39 |
1 files changed, 15 insertions, 24 deletions
diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 9fcb3ec7c83..70d330f8c99 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -27,28 +27,17 @@ extern __u32 syncookie_secret[2][16-4+SHA_DIGEST_WORDS]; #define COOKIEBITS 24 /* Upper bits store count */ #define COOKIEMASK (((__u32)1 << COOKIEBITS) - 1) -/* - * This table has to be sorted and terminated with (__u16)-1. - * XXX generate a better table. - * Unresolved Issues: HIPPI with a 64k MSS is not well supported. - * - * Taken directly from ipv4 implementation. - * Should this list be modified for ipv6 use or is it close enough? - * rfc 2460 8.3 suggests mss values 20 bytes less than ipv4 counterpart - */ +/* Table must be sorted. */ static __u16 const msstab[] = { - 64 - 1, - 256 - 1, - 512 - 1, - 536 - 1, - 1024 - 1, - 1440 - 1, - 1460 - 1, - 4312 - 1, - (__u16)-1 + 64, + 512, + 536, + 1280 - 60, + 1480 - 60, + 1500 - 60, + 4460 - 60, + 9000 - 60, }; -/* The number doesn't include the -1 terminator */ -#define NUM_MSS (ARRAY_SIZE(msstab) - 1) /* * This (misnamed) value is the age of syncookie which is permitted. @@ -134,9 +123,11 @@ __u32 cookie_v6_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mssp) tcp_synq_overflow(sk); - for (mssind = 0; mss > msstab[mssind + 1]; mssind++) - ; - *mssp = msstab[mssind] + 1; + for (mssind = ARRAY_SIZE(msstab) - 1; mssind ; mssind--) + if (mss >= msstab[mssind]) + break; + + *mssp = msstab[mssind]; NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_SYNCOOKIESSENT); @@ -154,7 +145,7 @@ static inline int cookie_check(struct sk_buff *skb, __u32 cookie) th->source, th->dest, seq, jiffies / (HZ * 60), COUNTER_TRIES); - return mssind < NUM_MSS ? msstab[mssind] + 1 : 0; + return mssind < ARRAY_SIZE(msstab) ? msstab[mssind] : 0; } struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) |