[B.A.T.M.A.N.] [PATCH v5 0/6] Optimizations for setups running dat and bla

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Andreas Pape

10 Jun 2016 10 Jun '16

11:10 a.m.

This patchset introduces optimizations for batman-adv in setups having several gateways into a common (switched) Ethernet backbone network especially if dat is additionally enabled.

Using the current implementation with bla and dat enabled, several problems can be observed in a real setup: 1. Multiplication of ARP replies from dat enabled gateways and dat enabled mesh nodes leading to an "ARP reply storm" in the common backbone network. 2. In rare corner cases bla does not fully prevent looping of unicast frames in the direction Backbone --> mesh --> backbone and looping of multicast frames in the direction mesh --> backbone --> mesh. The latter can lead to temporary confusion in the switched backbone resulting in packet loss and communication timeouts.

The observed problems are solved by introduction of additional rules for the dat handling, bla packet forwarding and bla claiming/unclaiming of clients.

v5: - changed function name to batadv_bla_check_claim - put added include file in alphabetical order - added check to exclude ip address 0.0.0.0 from snooping

v4: - removed unnecessary include in soft-interface.c - solved issue with double-use and refcounting of pointers in routing.c

v3:

- rebased patchset - moved snooping of ip addresses for dat speed up into separate function - removed "patch of a patch" - removed automatic claiming during check of a claim - fixed issues of the patchset not being compiled due to chosen batman options

Kind regards, Andreas

Andreas Pape (6): batman-adv: prevent multiple ARP replies sent by gateways if dat enbled batman-adv: speed up dat by snooping received ip traffic batman-adv: prevent duplication of ARP replies when DAT is used batman-adv: drop unicast packets from other backbone gw batman-adv: changed debug messages for easier bla debugging batman-adv: handle race condition for claims between gateways

net/batman-adv/bridge_loop_avoidance.c | 87 ++++++++++++++++++++++++--- net/batman-adv/bridge_loop_avoidance.h | 11 ++++ net/batman-adv/distributed-arp-table.c | 102 ++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 9 +++- net/batman-adv/routing.c | 25 +++++++- net/batman-adv/soft-interface.c | 3 + 6 files changed, 225 insertions(+), 12 deletions(-)

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Sitz der Gesellschaft / registered office of the company: 31812 Bad Pyrmont USt-Id-Nr.: DE811742156 Amtsgericht Hannover HRB 100528 / district court Hannover HRB 100528 Geschäftsführer / Executive Board: Roland Bent, Dr. Martin Heubeck ___________________________________________________________________ Diese E-Mail enthält vertrauliche und/oder rechtlich geschützte Informationen. Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtümlich erhalten haben, informieren Sie bitte sofort den Absender und vernichten Sie diese Mail. Das unerlaubte Kopieren, jegliche anderweitige Verwendung sowie die unbefugte Weitergabe dieser Mail ist nicht gestattet. ---------------------------------------------------------------------------------------------------- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure, distribution or other use of the material or parts thereof is strictly forbidden. ___________________________________________________________________

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Andreas Pape

10 Jun 10 Jun

11:10 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 1/6] batman-adv: prevent multiple ARP replies sent by gateways if dat enbled

If dat is enabled it must be made sure that only the backbone gw which has claimed the remote destination for the ARP request answers the ARP request directly if the MAC address is known due to the local dat table. This prevents multiple ARP replies in a common backbone if more than one gateway already knows the remote mac searched for in the ARP request.

Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/bridge_loop_avoidance.c | 49 ++++++++++++++++++++++++++++++++ net/batman-adv/bridge_loop_avoidance.h | 11 +++++++ net/batman-adv/distributed-arp-table.c | 15 ++++++++++ 3 files changed, 75 insertions(+), 0 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index 748a9ea..cd2d74b 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -2045,3 +2045,52 @@ out: batadv_hardif_put(primary_if); return 0; } + +#ifdef CONFIG_BATMAN_ADV_DAT +/** + * batadv_bla_check_claim - check if address is claimed + * + * @bat_priv: the bat priv with all the soft interface information + * @addr: mac address of which the claim status is checked + * @vid: the VLAN ID + * + * addr is checked if this address is claimed by the local device itself. + * + * Return: true if bla is disabled or the mac is claimed by the device, + * false if the device addr is already claimed by another gateway + */ +bool batadv_bla_check_claim(struct batadv_priv *bat_priv, + u8 *addr, unsigned short vid) +{ + struct batadv_bla_claim search_claim; + struct batadv_bla_claim *claim = NULL; + struct batadv_hard_iface *primary_if = NULL; + bool ret = true; + + if (!atomic_read(&bat_priv->bridge_loop_avoidance)) + return ret; + + primary_if = batadv_primary_if_get_selected(bat_priv); + if (!primary_if) + return ret; + + /* First look if the mac address is claimed */ + ether_addr_copy(search_claim.addr, addr); + search_claim.vid = vid; + + claim = batadv_claim_hash_find(bat_priv, &search_claim); + + /* If there is a claim and we are not owner of the claim, + * return false. + */ + if (claim) { + if (!batadv_compare_eth(claim->backbone_gw->orig, + primary_if->net_dev->dev_addr)) + ret = false; + batadv_claim_put(claim); + } + + batadv_hardif_put(primary_if); + return ret; +} +#endif diff --git a/net/batman-adv/bridge_loop_avoidance.h b/net/batman-adv/bridge_loop_avoidance.h index 0f01dae..9dddebc 100644 --- a/net/batman-adv/bridge_loop_avoidance.h +++ b/net/batman-adv/bridge_loop_avoidance.h @@ -47,6 +47,10 @@ void batadv_bla_update_orig_address(struct batadv_priv *bat_priv, void batadv_bla_status_update(struct net_device *net_dev); int batadv_bla_init(struct batadv_priv *bat_priv); void batadv_bla_free(struct batadv_priv *bat_priv); +#ifdef CONFIG_BATMAN_ADV_DAT +bool batadv_bla_check_claim(struct batadv_priv *bat_priv, u8 *addr, + unsigned short vid); +#endif

#define BATADV_BLA_CRC_INIT 0 #else /* ifdef CONFIG_BATMAN_ADV_BLA */ @@ -112,6 +116,13 @@ static inline void batadv_bla_free(struct batadv_priv *bat_priv) { }

+static inline +bool batadv_bla_check_claim(struct batadv_priv *bat_priv, u8 *addr, + unsigned short vid) +{ + return true; +} + #endif /* ifdef CONFIG_BATMAN_ADV_BLA */

#endif /* ifndef _NET_BATMAN_ADV_BLA_H_ */ diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 278800a..b752f8d 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -43,6 +43,7 @@ #include <linux/workqueue.h> #include <net/arp.h>

+#include "bridge_loop_avoidance.h" #include "hard-interface.h" #include "hash.h" #include "originator.h" @@ -1003,6 +1004,20 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv, goto out; }

+ /* If BLA is enabled, only send ARP replies if we have claimed + * the destination for the ARP request or if no one else of + * the backbone gws belonging to our backbone has claimed the + * destination. + */ + if (!batadv_bla_check_claim(bat_priv, + dat_entry->mac_addr, vid)) { + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "Device %pM claimed by another backbone gw. Don't send ARP reply!", + dat_entry->mac_addr); + ret = true; + goto out; + } + skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src, bat_priv->soft_iface, ip_dst, hw_src, dat_entry->mac_addr, hw_src); -- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Simon Wunderlich

1 Jul 1 Jul

1:52 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 1/6] batman-adv: prevent multiple ARP replies sent by gateways if dat enbled

On Friday 10 June 2016 13:10:59 Andreas Pape wrote:

...

If dat is enabled it must be made sure that only the backbone gw which has claimed the remote destination for the ARP request answers the ARP request directly if the MAC address is known due to the local dat table. This prevents multiple ARP replies in a common backbone if more than one gateway already knows the remote mac searched for in the ARP request.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

Acked-by: Simon Wunderlich sw@simonwunderlich.de

Please add my Acked-by on resend.

Thanks! Simon

Andreas Pape

10 Jun 10 Jun

11:11 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

Speeding up dat address lookup is achieved by snooping all incoming ip traffic. This especially increases the propability in bla setups that a gateway into a common backbone network already has a fitting dat entry to answer incoming ARP requests directly coming from the backbone network thus further reducing ARP traffic in the mesh.

Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/distributed-arp-table.c | 55 ++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 9 +++++- net/batman-adv/soft-interface.c | 3 ++ 3 files changed, 66 insertions(+), 1 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index b752f8d..998a4b8 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -27,6 +27,7 @@ #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> +#include <linux/ip.h> #include <linux/in.h> #include <linux/jiffies.h> #include <linux/kernel.h> @@ -362,6 +363,60 @@ out: batadv_dat_entry_put(dat_entry); }

+/** + * batadv_dat_entry_check - check and update a dat entry + * @bat_priv: the bat priv with all the soft interface information + * @skb: socket buffer + * @vid: VLAN identifier + * + * snoops incoming socket buffer for dat cache updates, if dat is enabled. + * Can be called from other modules. + */ +void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{ + struct vlan_ethhdr *vhdr = NULL, tmp_vhdr; + struct ethhdr *ethhdr = NULL; + struct iphdr *iphdr = NULL, tmp_iphdr; + + if (!atomic_read(&bat_priv->distributed_arp_table)) + return; + + ethhdr = eth_hdr(skb); + + switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IP: + iphdr = skb_header_pointer(skb, ETH_HLEN, sizeof(tmp_iphdr), + &tmp_iphdr); + break; + case ETH_P_8021Q: + vhdr = skb_header_pointer(skb, 0, sizeof(tmp_vhdr), + &tmp_vhdr); + if (!vhdr) + return; + if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_IP) + return; + iphdr = skb_header_pointer(skb, sizeof(tmp_vhdr), + sizeof(tmp_iphdr), + &tmp_iphdr); + break; + } + + if (!iphdr) + return; + /* don't add source address 0.0.0.0, which can occur during + * dhcp discover or request. + */ + if (ntohl(iphdr->saddr) == 0) + return; + + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "Snooped IP address: %pI4 %pM (vid: %d)\n", + &iphdr->saddr, ethhdr->h_source, + BATADV_PRINT_VID(vid)); + batadv_dat_entry_add(bat_priv, iphdr->saddr, ethhdr->h_source, vid); +} + #ifdef CONFIG_BATMAN_ADV_DEBUG

/** diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h index 813ecea..cf1b93c 100644 --- a/net/batman-adv/distributed-arp-table.h +++ b/net/batman-adv/distributed-arp-table.h @@ -80,7 +80,8 @@ batadv_dat_init_own_addr(struct batadv_priv *bat_priv, int batadv_dat_init(struct batadv_priv *bat_priv); void batadv_dat_free(struct batadv_priv *bat_priv); int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset); - +void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid); /** * batadv_dat_inc_counter - increment the correct DAT packet counter * @bat_priv: the bat priv with all the soft interface information @@ -173,6 +174,12 @@ static inline void batadv_dat_inc_counter(struct batadv_priv *bat_priv, { }

+static inline +void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{ +} + #endif /* CONFIG_BATMAN_ADV_DAT */

#endif /* _NET_BATMAN_ADV_DISTRIBUTED_ARP_TABLE_H_ */ diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 81665b1..a86748f 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -442,6 +442,9 @@ void batadv_interface_rx(struct net_device *soft_iface, goto dropped; }

+ /* Snoop incoming traffic for dat update */ + batadv_dat_entry_check(bat_priv, skb, vid); + /* skb->dev & skb->pkt_type are set here */ skb->protocol = eth_type_trans(skb, soft_iface);

-- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Sven Eckelmann

25 Jun 25 Jun

10:04 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

On Friday 10 June 2016 13:11:00 Andreas Pape wrote:

...

Speeding up dat address lookup is achieved by snooping all incoming ip traffic. This especially increases the propability in bla setups that a gateway into a common backbone network already has a fitting dat entry to answer incoming ARP requests directly coming from the backbone network thus further reducing ARP traffic in the mesh.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

Marking this as rejected in patchwork due to the conceptual problems pointed out by Matthias + Linus [1].

@Marek, I hope this helps to reduce the number of patches you have to go through in patchwork. But please feel free to change it back when you think differently about it.

Kind regards, Sven

[1] https://lists.open-mesh.org/pipermail/b.a.t.m.a.n/2016-June/015738.html

Ruben Wisniewski

26 Jun 26 Jun

8:54 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

Are new clients (Mac) not already spread as info on the network? So couldn't we not just snoop dhcp traffic on gateways and spread the info about acknowledged IPs as well?

...

Am 25.06.2016 um 12:04 schrieb Sven Eckelmann sven@narfation.org:

...
On Friday 10 June 2016 13:11:00 Andreas Pape wrote: Speeding up dat address lookup is achieved by snooping all incoming ip traffic. This especially increases the propability in bla setups that a gateway into a common backbone network already has a fitting dat entry to answer incoming ARP requests directly coming from the backbone network thus further reducing ARP traffic in the mesh.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

Marking this as rejected in patchwork due to the conceptual problems pointed out by Matthias + Linus [1].

@Marek, I hope this helps to reduce the number of patches you have to go through in patchwork. But please feel free to change it back when you think differently about it.

Kind regards, Sven

[1] https://lists.open-mesh.org/pipermail/b.a.t.m.a.n/2016-June/015738.html

Sven Eckelmann

9:29 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

On Sunday 26 June 2016 10:54:18 Ruben Wisniewski wrote:

...

Are new clients (Mac) not already spread as info on the network? So couldn't we not just snoop dhcp traffic on gateways and spread the info about acknowledged IPs as well?

Just a small info in case somebody wants to work on it:

batman-adv in gw server mode would only handle the DHCP replies (ACK, OFFER, ...) only when they are sent as broadcast. But it is a lot more efficient when the DHCPd sents replies as unicast packet.

Kind regards, Sven

Simon Wunderlich

1 Jul 1 Jul

1:49 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

Hi Andreas,

as suggested by yourself and according to the discussion, please drop this patch from the patchset on the next resend. It may be better to resend it separately when the concerns are cleared.

Thanks! Simon

On Friday 10 June 2016 13:11:00 Andreas Pape wrote:

...

Speeding up dat address lookup is achieved by snooping all incoming ip traffic. This especially increases the propability in bla setups that a gateway into a common backbone network already has a fitting dat entry to answer incoming ARP requests directly coming from the backbone network thus further reducing ARP traffic in the mesh.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

net/batman-adv/distributed-arp-table.c | 55 ++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 9 +++++- net/batman-adv/soft-interface.c | 3 ++ 3 files changed, 66 insertions(+), 1 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index b752f8d..998a4b8 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -27,6 +27,7 @@ #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> +#include <linux/ip.h> #include <linux/in.h> #include <linux/jiffies.h> #include <linux/kernel.h> @@ -362,6 +363,60 @@ out: batadv_dat_entry_put(dat_entry); }

+/**

batadv_dat_entry_check - check and update a dat entry

@bat_priv: the bat priv with all the soft interface information

@skb: socket buffer

@vid: VLAN identifier

snoops incoming socket buffer for dat cache updates, if dat is enabled.

Can be called from other modules.

*/

+void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{
struct vlan_ethhdr *vhdr = NULL, tmp_vhdr;

struct ethhdr *ethhdr = NULL;

struct iphdr *iphdr = NULL, tmp_iphdr;

if (!atomic_read(&bat_priv->distributed_arp_table))
return;
ethhdr = eth_hdr(skb);

switch (ntohs(ethhdr->h_proto)) {

case ETH_P_IP:
iphdr = skb_header_pointer(skb, ETH_HLEN, sizeof(tmp_iphdr),
			   &tmp_iphdr);
break;
case ETH_P_8021Q:
vhdr = skb_header_pointer(skb, 0, sizeof(tmp_vhdr),
			  &tmp_vhdr);
if (!vhdr)
	return;
if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_IP)
	return;
iphdr = skb_header_pointer(skb, sizeof(tmp_vhdr),
			   sizeof(tmp_iphdr),
			   &tmp_iphdr);
break;
}

if (!iphdr)
return;
/* don't add source address 0.0.0.0, which can occur during
* dhcp discover or request.
*/
if (ntohl(iphdr->saddr) == 0)
return;
batadv_dbg(BATADV_DBG_DAT, bat_priv,
   "Snooped IP address: %pI4 %pM (vid: %d)\n",
   &iphdr->saddr, ethhdr->h_source,
   BATADV_PRINT_VID(vid));
batadv_dat_entry_add(bat_priv, iphdr->saddr, ethhdr->h_source, vid);
+}

#ifdef CONFIG_BATMAN_ADV_DEBUG

/** diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h index 813ecea..cf1b93c 100644 --- a/net/batman-adv/distributed-arp-table.h +++ b/net/batman-adv/distributed-arp-table.h @@ -80,7 +80,8 @@ batadv_dat_init_own_addr(struct batadv_priv *bat_priv, int batadv_dat_init(struct batadv_priv *bat_priv); void batadv_dat_free(struct batadv_priv *bat_priv); int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset);

+void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid); /**

batadv_dat_inc_counter - increment the correct DAT packet counter

@bat_priv: the bat priv with all the soft interface information

@@ -173,6 +174,12 @@ static inline void batadv_dat_inc_counter(struct batadv_priv *bat_priv, { }

+static inline +void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{ +}

#endif /* CONFIG_BATMAN_ADV_DAT */

#endif /* _NET_BATMAN_ADV_DISTRIBUTED_ARP_TABLE_H_ */ diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 81665b1..a86748f 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -442,6 +442,9 @@ void batadv_interface_rx(struct net_device *soft_iface, goto dropped; }

/* Snoop incoming traffic for dat update */

batadv_dat_entry_check(bat_priv, skb, vid);

/* skb->dev & skb->pkt_type are set here */ skb->protocol = eth_type_trans(skb, soft_iface);

-- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Sitz der Gesellschaft / registered office of the company: 31812 Bad Pyrmont USt-Id-Nr.: DE811742156 Amtsgericht Hannover HRB 100528 / district court Hannover HRB 100528 Geschäftsführer / Executive Board: Roland Bent, Dr. Martin Heubeck ___________________________________________________________________ Diese E-Mail enthält vertrauliche und/oder rechtlich geschützte Informationen. Wenn Sie nicht der richtige Adressat sind oder diese E-Mail irrtümlich erhalten haben, informieren Sie bitte sofort den Absender und vernichten Sie diese Mail. Das unerlaubte Kopieren, jegliche anderweitige Verwendung sowie die unbefugte Weitergabe dieser Mail ist nicht gestattet.

------------------------- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and destroy this e-mail. Any unauthorized copying, disclosure, distribution or other use of the material or parts thereof is strictly forbidden. ___________________________________________________________________

Linus Lüssing

19 Jul 19 Jul

6:29 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

Hi Andreas,

After the observations in ticket #291 [0], Antonio and I had been discussing this topic a little further on IRC.

The Linux kernel seems to refresh its ARP table by snooping the IP traffic, too. But IP traffic does not create any ARP table entries.

What do you think about doing the same in batman-adv? That is, only updating, but not creating DAT cache entries from IP traffic. That should get rid of the main two concerns, accidentally snooping routed IP traffic and performance implications, shouldn't it?

Regards, Linus

On Fri, Jul 01, 2016 at 03:49:54PM +0200, Simon Wunderlich wrote:

...

Hi Andreas,

as suggested by yourself and according to the discussion, please drop this patch from the patchset on the next resend. It may be better to resend it separately when the concerns are cleared.

Thanks! Simon

On Friday 10 June 2016 13:11:00 Andreas Pape wrote:

...
Speeding up dat address lookup is achieved by snooping all incoming ip traffic. This especially increases the propability in bla setups that a gateway into a common backbone network already has a fitting dat entry to answer incoming ARP requests directly coming from the backbone network thus further reducing ARP traffic in the mesh.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

net/batman-adv/distributed-arp-table.c | 55 ++++++++++++++++++++++++++++++++ net/batman-adv/distributed-arp-table.h | 9 +++++- net/batman-adv/soft-interface.c | 3 ++ 3 files changed, 66 insertions(+), 1 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index b752f8d..998a4b8 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -27,6 +27,7 @@ #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> +#include <linux/ip.h> #include <linux/in.h> #include <linux/jiffies.h> #include <linux/kernel.h> @@ -362,6 +363,60 @@ out: batadv_dat_entry_put(dat_entry); }

+/**

batadv_dat_entry_check - check and update a dat entry

@bat_priv: the bat priv with all the soft interface information

@skb: socket buffer

@vid: VLAN identifier

snoops incoming socket buffer for dat cache updates, if dat is enabled.

Can be called from other modules.

*/

+void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{
struct vlan_ethhdr *vhdr = NULL, tmp_vhdr;

struct ethhdr *ethhdr = NULL;

struct iphdr *iphdr = NULL, tmp_iphdr;

if (!atomic_read(&bat_priv->distributed_arp_table))
return;
ethhdr = eth_hdr(skb);

switch (ntohs(ethhdr->h_proto)) {

case ETH_P_IP:
iphdr = skb_header_pointer(skb, ETH_HLEN, sizeof(tmp_iphdr),
			   &tmp_iphdr);
break;
case ETH_P_8021Q:
vhdr = skb_header_pointer(skb, 0, sizeof(tmp_vhdr),
			  &tmp_vhdr);
if (!vhdr)
	return;
if (ntohs(vhdr->h_vlan_encapsulated_proto) != ETH_P_IP)
	return;
iphdr = skb_header_pointer(skb, sizeof(tmp_vhdr),
			   sizeof(tmp_iphdr),
			   &tmp_iphdr);
break;
}

if (!iphdr)
return;
/* don't add source address 0.0.0.0, which can occur during
* dhcp discover or request.
*/
if (ntohl(iphdr->saddr) == 0)
return;
batadv_dbg(BATADV_DBG_DAT, bat_priv,
   "Snooped IP address: %pI4 %pM (vid: %d)\n",
   &iphdr->saddr, ethhdr->h_source,
   BATADV_PRINT_VID(vid));
batadv_dat_entry_add(bat_priv, iphdr->saddr, ethhdr->h_source, vid);
+}

#ifdef CONFIG_BATMAN_ADV_DEBUG

/** diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h index 813ecea..cf1b93c 100644 --- a/net/batman-adv/distributed-arp-table.h +++ b/net/batman-adv/distributed-arp-table.h @@ -80,7 +80,8 @@ batadv_dat_init_own_addr(struct batadv_priv *bat_priv, int batadv_dat_init(struct batadv_priv *bat_priv); void batadv_dat_free(struct batadv_priv *bat_priv); int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset);

+void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid); /**

batadv_dat_inc_counter - increment the correct DAT packet counter

@bat_priv: the bat priv with all the soft interface information

@@ -173,6 +174,12 @@ static inline void batadv_dat_inc_counter(struct batadv_priv *bat_priv, { }

+static inline +void batadv_dat_entry_check(struct batadv_priv *bat_priv, struct sk_buff *skb, + unsigned short vid) +{ +}

#endif /* CONFIG_BATMAN_ADV_DAT */

#endif /* _NET_BATMAN_ADV_DISTRIBUTED_ARP_TABLE_H_ */ diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 81665b1..a86748f 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -442,6 +442,9 @@ void batadv_interface_rx(struct net_device *soft_iface, goto dropped; }

/* Snoop incoming traffic for dat update */

batadv_dat_entry_check(bat_priv, skb, vid);

/* skb->dev & skb->pkt_type are set here */ skb->protocol = eth_type_trans(skb, soft_iface);

-- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

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Sven Eckelmann

6:59 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

On Dienstag, 19. Juli 2016 08:29:07 CEST Linus Lüssing wrote:

...

What do you think about doing the same in batman-adv? That is, only updating, but not creating DAT cache entries from IP traffic. That should get rid of the main two concerns, accidentally snooping routed IP traffic and performance implications, shouldn't it?

You have to snoop the traffic anyway and search in the dat cache for each(?) packet. And the DAT cache is distributed. So why would it avoid the performance implications?

Kind regards, Sven

Ruben Wisniewski

7:06 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

What exactly is the target of it? Just refresh the timer for arp entries? Why don't just ask the kernel arp table if it knows something bout the mac-address?

Every change should be pushed through the network by ne node which detected a new client, don't it?

Best regards

Ruben

...

Am 19.07.2016 um 08:59 schrieb Sven Eckelmann sven@narfation.org:

...
On Dienstag, 19. Juli 2016 08:29:07 CEST Linus Lüssing wrote: What do you think about doing the same in batman-adv? That is, only updating, but not creating DAT cache entries from IP traffic. That should get rid of the main two concerns, accidentally snooping routed IP traffic and performance implications, shouldn't it?

You have to snoop the traffic anyway and search in the dat cache for each(?) packet. And the DAT cache is distributed. So why would it avoid the performance implications?

Kind regards, Sven

Linus Lüssing

4:15 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

On Tue, Jul 19, 2016 at 09:06:38AM +0200, Ruben Wisniewski wrote:

...

What exactly is the target of it? Just refresh the timer for arp entries? Why don't just ask the kernel arp table if it knows something bout the mac-address?

Yes, refreshing DAT cache entry timers more frequently was the idea.

There usually is no entry in a host's ARP table if bridges are involved, though. Which is the typical use-case with batman-adv.

Regards, Linus

Linus Lüssing

4:13 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 2/6] batman-adv: speed up dat by snooping received ip traffic

On Tue, Jul 19, 2016 at 08:59:01AM +0200, Sven Eckelmann wrote:

...

On Dienstag, 19. Juli 2016 08:29:07 CEST Linus Lüssing wrote:

...
What do you think about doing the same in batman-adv? That is, only updating, but not creating DAT cache entries from IP traffic. That should get rid of the main two concerns, accidentally snooping routed IP traffic and performance implications, shouldn't it?

You have to snoop the traffic anyway and search in the dat cache for each(?) packet. And the DAT cache is distributed. So why would it avoid the performance implications?

I was talking about the local DAT cache. Not the DHT. Antonio and I were thinking about a ratelimited DHT_PUT, too, but he wanted to give it some further thoughts. No DHT_GET involved.

Also, Andreas already took care that the snooping code only uses stack and not heap memory. No pskb_may_pull, just skb_head_pointer()s. So if we were removing the DAT entry creation, then there'd be no more kmalloc()'s.

A hashmap lookup in the local DAT cache shouldn't be that costly either, should it? (and we are doing one such lookup for the originator and translation table each already anyway)

Regards, Linus

Andreas Pape

10 Jun 10 Jun

11:11 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 3/6] batman-adv: prevent duplication of ARP replies when DAT is used

If none of the backbone gateways in a bla setup has already knowledge of the mac address searched for in an incoming ARP request from the backbone an address resolution via the DHT of DAT is started. The gateway can send several ARP requests to different DHT nodes and therefore can get several replies. This patch assures that not all of the possible ARP replies are returned to the backbone by checking the local DAT cache of the gateway. If there is an entry in the local cache the gateway has already learned the requested address and there is no need to forward the additional reply to the backbone. Furthermore it is checked if this gateway has claimed the source of the ARP reply and only forwards it to the backbone if it has claimed the source or if there is no claim at all.

Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/distributed-arp-table.c | 32 ++++++++++++++++++++++++++++++++ 1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 998a4b8..e7b054a 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -1244,6 +1244,7 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, __be32 ip_src, ip_dst; u8 *hw_src, *hw_dst; bool dropped = false; + struct batadv_dat_entry *dat_entry = NULL; unsigned short vid;

if (!atomic_read(&bat_priv->distributed_arp_table)) @@ -1263,12 +1264,41 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, hw_dst = batadv_arp_hw_dst(skb, hdr_size); ip_dst = batadv_arp_ip_dst(skb, hdr_size);

+ /* If ip_dst is already in cache and has the right mac address, + * drop this frame if this ARP reply is destined for us because it's + * most probably an ARP reply generated by another node of the DHT. + * We have most probably received already a reply earlier. Delivering + * this frame would lead to doubled receive of an ARP reply. + */ + dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_src, vid); + if ((dat_entry) && (batadv_compare_eth(hw_src, dat_entry->mac_addr))) { + batadv_dbg(BATADV_DBG_DAT, bat_priv, "Doubled ARP reply removed: ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]; dat_entry: %pM-%pI4\n", + hw_src, &ip_src, hw_dst, &ip_dst, + dat_entry->mac_addr, &dat_entry->ip); + dropped = true; + goto out; + } + /* Update our internal cache with both the IP addresses the node got * within the ARP reply */ batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid); batadv_dat_entry_add(bat_priv, ip_dst, hw_dst, vid);

+ /* If BLA is enabled, only forward ARP replies if we have claimed the + * source of the ARP reply or if no one else of the same backbone has + * already claimed that client. This prevents that different gateways + * to the same backbone all forward the ARP reply leading to multiple + * replies in the backbone. + */ + if (!batadv_bla_check_claim(bat_priv, hw_src, vid)) { + batadv_dbg(BATADV_DBG_DAT, bat_priv, + "Device %pM claimed by another backbone gw. Drop ARP reply.\n", + hw_src); + dropped = true; + goto out; + } + /* if this REPLY is directed to a client of mine, let's deliver the * packet to the interface */ @@ -1281,6 +1311,8 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, out: if (dropped) kfree_skb(skb); + if (dat_entry) + batadv_dat_entry_put(dat_entry); /* if dropped == false -> deliver to the interface */ return dropped; } -- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Simon Wunderlich

1 Jul 1 Jul

2:11 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 3/6] batman-adv: prevent duplication of ARP replies when DAT is used

On Friday 10 June 2016 13:11:01 Andreas Pape wrote:

...

If none of the backbone gateways in a bla setup has already knowledge of the mac address searched for in an incoming ARP request from the backbone an address resolution via the DHT of DAT is started. The gateway can send several ARP requests to different DHT nodes and therefore can get several replies. This patch assures that not all of the possible ARP replies are returned to the backbone by checking the local DAT cache of the gateway. If there is an entry in the local cache the gateway has already learned the requested address and there is no need to forward the additional reply to the backbone. Furthermore it is checked if this gateway has claimed the source of the ARP reply and only forwards it to the backbone if it has claimed the source or if there is no claim at all.

Acked-by: Simon Wunderlich sw@simonwunderlich.de

but one small style suggestion below:

...

Signed-off-by: Andreas Pape apape@phoenixcontact.com

net/batman-adv/distributed-arp-table.c | 32 ++++++++++++++++++++++++++++++++ 1 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 998a4b8..e7b054a 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -1244,6 +1244,7 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, __be32 ip_src, ip_dst; u8 *hw_src, *hw_dst; bool dropped = false;

struct batadv_dat_entry *dat_entry = NULL; unsigned short vid;

if (!atomic_read(&bat_priv->distributed_arp_table))

@@ -1263,12 +1264,41 @@ bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv, hw_dst = batadv_arp_hw_dst(skb, hdr_size); ip_dst = batadv_arp_ip_dst(skb, hdr_size);
/* If ip_dst is already in cache and has the right mac address,
* drop this frame if this ARP reply is destined for us because it's
* most probably an ARP reply generated by another node of the DHT.
* We have most probably received already a reply earlier. Delivering
* this frame would lead to doubled receive of an ARP reply.
*/
dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_src, vid);

if ((dat_entry) && (batadv_compare_eth(hw_src, dat_entry->mac_addr))) {

you can drop the braces for dat_entry and batadv_compare_eth here.

Cheers, Simon

Andreas Pape

10 Jun 10 Jun

11:11 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 4/6] batman-adv: drop unicast packets from other backbone gw

Additional dropping of unicast packets received from another backbone gw of the same backbone network before being forwarded to the same backbone again is necessary. It was observed in a test setup that in rare cases these frames lead to looping unicast traffic backbone->mesh->backbone.

Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/routing.c | 25 ++++++++++++++++++++++--- 1 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index e3857ed..667e2cd 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -861,14 +861,16 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface); struct batadv_unicast_packet *unicast_packet; struct batadv_unicast_4addr_packet *unicast_4addr_packet; - u8 *orig_addr; - struct batadv_orig_node *orig_node = NULL; + u8 *orig_addr, *orig_addr_gw; + struct batadv_orig_node *orig_node = NULL, *orig_node_gw = NULL; int check, hdr_size = sizeof(*unicast_packet); enum batadv_subtype subtype; - bool is4addr; + bool is4addr, is_gw; + struct ethhdr *ethhdr;

unicast_packet = (struct batadv_unicast_packet *)skb->data; unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data; + ethhdr = eth_hdr(skb);

is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR; /* the caller function should have already pulled 2 bytes */ @@ -891,6 +893,23 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,

/* packet for me */ if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) { + /* If this is a unicast packet from another backgone gw, + * drop it. + */ + orig_addr_gw = ethhdr->h_source; + orig_node_gw = batadv_orig_hash_find(bat_priv, orig_addr_gw); + if (orig_node_gw) { + is_gw = batadv_bla_is_backbone_gw(skb, orig_node_gw, + hdr_size); + batadv_orig_node_put(orig_node_gw); + if (is_gw) { + batadv_dbg(BATADV_DBG_BLA, bat_priv, + "Dropped unicast pkt received from another backbone gw %pM.\n", + orig_addr_gw); + return NET_RX_DROP; + } + } + if (is4addr) { subtype = unicast_4addr_packet->subtype; batadv_dat_inc_counter(bat_priv, subtype); -- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Simon Wunderlich

1 Jul 1 Jul

1:48 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 4/6] batman-adv: drop unicast packets from other backbone gw

On Friday 10 June 2016 13:11:02 Andreas Pape wrote:

...

Additional dropping of unicast packets received from another backbone gw of the same backbone network before being forwarded to the same backbone again is necessary. It was observed in a test setup that in rare cases these frames lead to looping unicast traffic backbone->mesh->backbone.

Signed-off-by: Andreas Pape apape@phoenixcontact.com

Acked-by: Simon Wunderlich sw@simonwunderlich.de

I believe Svens previous concerns have been cleared. When you resend this patchset, please add my Acked-by into your commit message (unless you do major changes in the content ...)

Thanks, Simon

Andreas Pape

10 Jun 10 Jun

11:11 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 5/6] batman-adv: changed debug messages for easier bla debugging

Some of the bla debug messages are extended and additional messages are added for easier bla debugging. Some debug messages introduced with the dat changes in prior patches of this patch series have been changed to be more compliant to other existing debug messages.

Acked-by: Simon Wunderlich sw@simonwunderlich.de Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/bridge_loop_avoidance.c | 18 ++++++++++++++---- net/batman-adv/routing.c | 2 +- 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index cd2d74b..2ccce6e 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -715,8 +715,8 @@ static void batadv_bla_add_claim(struct batadv_priv *bat_priv, goto claim_free_ref;

batadv_dbg(BATADV_DBG_BLA, bat_priv, - "bla_add_claim(): changing ownership for %pM, vid %d\n", - mac, BATADV_PRINT_VID(vid)); + "bla_add_claim(): changing ownership for %pM, vid %d to gw %pM\n", + mac, BATADV_PRINT_VID(vid), backbone_gw->orig);

spin_lock_bh(&claim->backbone_gw->crc_lock); claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN); @@ -1240,10 +1240,13 @@ static void batadv_bla_purge_claims(struct batadv_priv *bat_priv, continue;

batadv_dbg(BATADV_DBG_BLA, bat_priv, - "bla_purge_claims(): %pM, vid %d, time out\n", + "bla_purge_claims(): timed out.\n"); + +purge_now: + batadv_dbg(BATADV_DBG_BLA, bat_priv, + "bla_purge_claims(): %pM, vid %d\n", claim->addr, claim->vid);

-purge_now: batadv_handle_unclaim(bat_priv, primary_if, claim->backbone_gw->orig, claim->addr, claim->vid); @@ -1787,6 +1790,13 @@ bool batadv_bla_rx(struct batadv_priv *bat_priv, struct sk_buff *skb, /* possible optimization: race for a claim */ /* No claim exists yet, claim it for us! */ + + batadv_dbg(BATADV_DBG_BLA, bat_priv, + "bla_rx(): Unclaimed MAC %pM found. Claim it. Local: %s\n", + ethhdr->h_source, + batadv_is_my_client(bat_priv, + ethhdr->h_source, vid) ? + "yes" : "no"); batadv_handle_claim(bat_priv, primary_if, primary_if->net_dev->dev_addr, ethhdr->h_source, vid); diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 667e2cd..7eeae86 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -904,7 +904,7 @@ int batadv_recv_unicast_packet(struct sk_buff *skb, batadv_orig_node_put(orig_node_gw); if (is_gw) { batadv_dbg(BATADV_DBG_BLA, bat_priv, - "Dropped unicast pkt received from another backbone gw %pM.\n", + "recv_unicast_packet(): Dropped unicast pkt received from another backbone gw %pM.\n", orig_addr_gw); return NET_RX_DROP; } -- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Andreas Pape

11:11 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 6/6] batman-adv: handle race condition for claims between gateways

Consider the following situation which has been found in a test setup: Gateway B has claimed client C and gateway A has the same backbone network as B. C sends a broad- or multicast to B and directly after this packet decides to send another packet to A due to a better TQ value. B will forward the broad-/multicast into the backbone as it is the responsible gw and after that A will claim C as it has been chosen by C as the best gateway. If it now happens that A claims C before it has received the broad-/multicast forwarded by B (due to backbone topology or due to some delay in B when forwarding the packet) we get a critical situation: in the current code A will immediately unclaim C when receiving the multicast due to the roaming client scenario although the position of C has not changed in the mesh. If this happens the multi-/broadcast forwarded by B will be sent back into the mesh by A and we have looping packets until one of the gateways claims C again. In order to prevent this, unclaiming of a client due to the roaming client scenario is only done after a certain time is expired after the last claim of the client. 100 ms are used here, which should be slow enough for big backbones and slow gateways but fast enough not to break the roaming client use case.

Acked-by: Simon Wunderlich sw@simonwunderlich.de Signed-off-by: Andreas Pape apape@phoenixcontact.com --- net/batman-adv/bridge_loop_avoidance.c | 20 ++++++++++++++++---- 1 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c index 2ccce6e..4c3b294 100644 --- a/net/batman-adv/bridge_loop_avoidance.c +++ b/net/batman-adv/bridge_loop_avoidance.c @@ -1904,10 +1904,22 @@ bool batadv_bla_tx(struct batadv_priv *bat_priv, struct sk_buff *skb, /* if yes, the client has roamed and we have * to unclaim it. */ - batadv_handle_unclaim(bat_priv, primary_if, - primary_if->net_dev->dev_addr, - ethhdr->h_source, vid); - goto allow; + if (batadv_has_timed_out(claim->lasttime, 100)) { + /* only unclaim if the last claim entry is + * older than 100 ms to make sure we really + * have a roaming client here. + */ + batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_tx(): Roaming client %pM detected. Unclaim it.\n", + ethhdr->h_source); + batadv_handle_unclaim(bat_priv, primary_if, + primary_if->net_dev->dev_addr, + ethhdr->h_source, vid); + goto allow; + } else { + batadv_dbg(BATADV_DBG_BLA, bat_priv, "bla_tx(): Race for claim %pM detected. Drop packet.\n", + ethhdr->h_source); + goto handled; + } }

/* check if it is a multicast/broadcast frame */ -- 1.7.0.4

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Sven Eckelmann

11:51 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 0/6] Optimizations for setups running dat and bla

On Friday 10 June 2016 13:10:58 Andreas Pape wrote:

...

This patchset introduces optimizations for batman-adv in setups having several gateways into a common (switched) Ethernet backbone network especially if dat is additionally enabled.

Using the current implementation with bla and dat enabled, several problems can be observed in a real setup:

Multiplication of ARP replies from dat enabled gateways and dat enabled

mesh nodes leading to an "ARP reply storm" in the common backbone network. 2. In rare corner cases bla does not fully prevent looping of unicast frames in the direction Backbone --> mesh --> backbone and looping of multicast frames in the direction mesh --> backbone --> mesh. The latter can lead to temporary confusion in the switched backbone resulting in packet loss and communication timeouts.

The observed problems are solved by introduction of additional rules for the dat handling, bla packet forwarding and bla claiming/unclaiming of clients.

v5:

changed function name to batadv_bla_check_claim

put added include file in alphabetical order

added check to exclude ip address 0.0.0.0 from snooping

Doesn't seem to apply:

$ git describe v2016.2-50-g3ce003c $ git am ~/bundle-11-datbla.mbox Applying: batman-adv: prevent multiple ARP replies sent by gateways if dat enbled error: patch failed: net/batman-adv/distributed-arp-table.c:43 error: net/batman-adv/distributed-arp-table.c: patch does not apply Patch failed at 0001 batman-adv: prevent multiple ARP replies sent by gateways if dat enbled The copy of the patch that failed is found in: .git/rebase-apply/patch When you have resolved this problem, run "git am --continue". If you prefer to skip this patch, run "git am --skip" instead. To restore the original branch and stop patching, run "git am --abort".

Btw. there seems to be an "a" missing in "enabled" of the Subject of the first patch :)

Kind regards, Sven

Andreas Pape

13 Jun 13 Jun

8:06 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 0/6] Optimizations for setups running dat and bla

Hi Sven,

thanks for the feedback. I just realized that I forgot to rebase the patchset before sending it. Could this be the cause? When I try to apply the patches locally to a fresh cloned batman-adv repository, the patches succeeded but some hunks succeed with some offset or fuzz only due to the missing rebase.

...

Doesn't seem to apply:
$ git describe
v2016.2-50-g3ce003c
$ git am ~/bundle-11-datbla.mbox
Applying: batman-adv: prevent multiple ARP replies sent by
gateways if dat enbled error: patch failed: net/batman-adv/distributed-arp-table.c:43 error: net/batman-adv/distributed-arp-table.c: patch does not apply Patch failed at 0001 batman-adv: prevent multiple ARP replies sent by gateways if dat enbled The copy of the patch that failed is found in:

.git/rebase-apply/patch

...

When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am

--abort".

...

Btw. there seems to be an "a" missing in "enabled" of the Subject of the first patch :)

Will be corrected as there's another version obviously necessary ...;-)

Best regards, Andreas

.................................................................. PHOENIX CONTACT ELECTRONICS GmbH

Sven Eckelmann

9:01 a.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 0/6] Optimizations for setups running dat and bla

On Monday 13 June 2016 10:06:55 Andreas Pape wrote:

...

...
Btw. there seems to be an "a" missing in "enabled" of the Subject of the first patch :)

Will be corrected as there's another version obviously necessary ...;-)

Maybe there are other comments from Simon oder Antonio. But I think there are still open questions from them as reply to the patches for v3 of the patchset. At least I cannot find any replies on the mailing list.

Kind regards, Sven

Simon Wunderlich

1 Jul 1 Jul

2:12 p.m.

New subject: [B.A.T.M.A.N.] [PATCH v5 0/6] Optimizations for setups running dat and bla

On Monday 13 June 2016 11:01:54 Sven Eckelmann wrote:

...

On Monday 13 June 2016 10:06:55 Andreas Pape wrote:

...
...
Btw. there seems to be an "a" missing in "enabled" of the Subject of the first patch :)

Will be corrected as there's another version obviously necessary ...;-)

Maybe there are other comments from Simon oder Antonio. But I think there are still open questions from them as reply to the patches for v3 of the patchset. At least I cannot find any replies on the mailing list.

Hi Andreas,

sorry for the late review. I think we are through from my end, your patches mostly require a rebase and some small change. I'd also drop one of the patches and submit them separately to get the other patches through.

Thanks! Simon

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Andreas Pape
Andreas Pape
Linus Lüssing
Ruben Wisniewski
Simon Wunderlich
Sven Eckelmann