Re: [B.A.T.M.A.N.] [PATCHv5 9/9] batman-adv: Distributed ARP Table - use unicast_4addr_packet for DHT messages

[Marek Lindner <lindner_marek@yahoo.de>]

On Friday, February 10, 2012 07:41:42 Antonio Quartulli wrote:
> In order to enable an higher verbosity level of the DAT debug messages, the
> unicast_4addr_packet is now used to carry ARP packets generated by the DAT
> internal mechanism. This packet type will enable batman-adv to recognise
> each DAT related message and to print its source (this will help to track
> possibly bogus ARP entries)
> 
> Signed-off-by: Antonio Quartulli <ordex@autistici.org>
> ---
>  distributed-arp-table.c |  129
> +++++++++++++++++++++++++++++++--------------- distributed-arp-table.h |  
> 16 +++---
>  soft-interface.c        |   15 +++--
>  3 files changed, 105 insertions(+), 55 deletions(-)
> 
> diff --git a/distributed-arp-table.c b/distributed-arp-table.c
> index 48e97e0..239b5c4 100644
> --- a/distributed-arp-table.c
> +++ b/distributed-arp-table.c
> @@ -31,6 +31,7 @@
>  #include "originator.h"
>  #include "send.h"
>  #include "soft-interface.h"
> +#include "translation-table.h"
>  #include "types.h"
>  #include "translation-table.h"
>  #include "unicast.h"
> @@ -38,10 +39,44 @@
>  #ifdef CONFIG_BATMAN_ADV_DEBUG
> 
>  static inline void bat_dbg_arp(struct bat_priv *bat_priv,
> -			       struct sk_buff *skb, uint16_t type) {
> +			       struct sk_buff *skb, uint16_t type,
> +			       int hdr_size) {
> +	struct unicast_4addr_packet *unicast_4addr_packet;
> +
>  	bat_dbg(DBG_ARP, bat_priv, "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n",
> -		ARP_HW_SRC(skb), &ARP_IP_SRC(skb), ARP_HW_DST(skb),
> -		&ARP_IP_DST(skb));
> +		ARP_HW_SRC(skb, hdr_size), &ARP_IP_SRC(skb, hdr_size),
> +		ARP_HW_DST(skb, hdr_size), &ARP_IP_DST(skb, hdr_size));
> +
> +	if (hdr_size == 0)
> +		return;
> +
> +	/* if the AP packet is encapsulated in a batman packet, let's print some
> +	 * debug messages */
> +	unicast_4addr_packet = (struct unicast_4addr_packet *)skb->data;
> +
> +	switch (unicast_4addr_packet->u.header.packet_type) {
> +	case BAT_UNICAST:
> +		bat_dbg(DBG_ARP, bat_priv, "encapsulated within a UNICAST "
> +			"packet\n");
> +		break;
> +	case BAT_UNICAST_4ADDR:
> +		bat_dbg(DBG_ARP, bat_priv, "encapsulated within a "
> +			"UNICAST_4ADDR packet (src: %pM)\n",
> +			unicast_4addr_packet->src);
> +		if (unicast_4addr_packet->subtype != BAT_P_DHT_PUT ||
> +		    unicast_4addr_packet->subtype != BAT_P_DHT_GET)
> +			bat_dbg(DBG_ARP, bat_priv, "It's a DAT message\n");

Isn't this check going to fail as soon as a new subtype was added ?


> +	unicast_4addr_packet = (struct unicast_4addr_packet *)skb->data;
> +
> +	if (dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
> +		goto out;
> +
> +	if (dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
> +		goto out;
> +

The unicast_4addr_packet variable isn't used anywhere ...

Most of this patch simply adds a hdr_size variable to the functions added by 
earlier patches. Why not adding the unicast_4addr type at the beginning of the 
patch series ? You would not need this patch.

Cheers,
Marek