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| author | Simon Wunderlich <siwu@hrz.tu-chemnitz.de> | 2010-06-22 01:25:51 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-06-22 14:05:06 -0700 |
| commit | cf2d72ec5c66ac3ebe9d28c3d88314a958cc180e (patch) | |
| tree | 186fd2f2f9bc7d08f4e25d7d503cd9192997b0a3 /drivers/staging/batman-adv/soft-interface.c | |
| parent | 6856ba1f44522b381c9a60b7972dd0fb52c54093 (diff) | |
| download | op-kernel-dev-cf2d72ec5c66ac3ebe9d28c3d88314a958cc180e.zip op-kernel-dev-cf2d72ec5c66ac3ebe9d28c3d88314a958cc180e.tar.gz | |
Staging: batman-adv: 32bit sequence number and TTL for broadcasts
This patch changes the sequence number range from 8 or 16 bit to 32 bit.
This should avoid problems with the sequence number sliding window algorithm
which we had seen in the past for broadcast floods or malicious packet
injections. We can not assure 100% security with this patch, but it is quite
an improvement over the old 16 bit sequence numbers:
* expected window size can be increased (4096 -> 65536)
* 64k packets in the right order would now be needed to cause a loop,
which seems practically impossible.
Furthermore, a TTL field has been added to the broadcast packet type, just to
make sure.
These changes required to increase the compatibility level once again.
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
[sven.eckelmann@gmx.de: Change atomic64_* back to atomic_*, Rework on
top of current version]
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/staging/batman-adv/soft-interface.c')
| -rw-r--r-- | drivers/staging/batman-adv/soft-interface.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/staging/batman-adv/soft-interface.c b/drivers/staging/batman-adv/soft-interface.c index c483693..ce789a7 100644 --- a/drivers/staging/batman-adv/soft-interface.c +++ b/drivers/staging/batman-adv/soft-interface.c @@ -30,7 +30,7 @@ #include <linux/ethtool.h> #include <linux/etherdevice.h> -static uint16_t bcast_seqno = 1; /* give own bcast messages seq numbers to avoid +static uint32_t bcast_seqno = 1; /* give own bcast messages seq numbers to avoid * broadcast storms */ static int32_t skb_packets; static int32_t skb_bad_packets; @@ -155,6 +155,7 @@ int interface_tx(struct sk_buff *skb, struct net_device *dev) bcast_packet = (struct bcast_packet *)skb->data; bcast_packet->version = COMPAT_VERSION; + bcast_packet->ttl = TTL; /* batman packet type: broadcast */ bcast_packet->packet_type = BAT_BCAST; @@ -164,7 +165,7 @@ int interface_tx(struct sk_buff *skb, struct net_device *dev) memcpy(bcast_packet->orig, mainIfAddr, ETH_ALEN); /* set broadcast sequence number */ - bcast_packet->seqno = htons(bcast_seqno); + bcast_packet->seqno = htonl(bcast_seqno); /* broadcast packet. on success, increase seqno. */ if (add_bcast_packet_to_list(skb) == NETDEV_TX_OK) |
