[1/6] batman-adv: implement an helper function to forge unicast packets
Commit Message
A new function named prepare_unicast_packet() has been implemented so that it can
do all the needed operations to set up a skb for unicast sending. It is general
enough to be used in every context. Helpful for later developments
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
---
unicast.c | 48 ++++++++++++++++++++++++++++++++----------------
unicast.h | 2 ++
2 files changed, 34 insertions(+), 16 deletions(-)
Comments
On Sun, Oct 30, 2011 at 09:55:57AM +0100, Antonio Quartulli wrote:
> @@ -304,33 +331,22 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
> orig_node = transtable_search(bat_priv, ethhdr->h_source,
> ethhdr->h_dest);
>
> -find_router:
> +prepare_packet:
> /**
> * find_router():
I guess the comment should be changed as well when the label is renamed.
> * - if orig_node is NULL it returns NULL
> * - increases neigh_nodes refcount if found.
> */
> neigh_node = find_router(bat_priv, orig_node, NULL);
> -
Do we really need to remove this newline?
> if (!neigh_node)
> goto out;
>
> - if (my_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
> + skb = prepare_unicast_packet(skb, orig_node);
> + if (!skb)
> goto out;
>
> unicast_packet = (struct unicast_packet *)skb->data;
>
> - unicast_packet->version = COMPAT_VERSION;
> - /* batman packet type: unicast */
> - unicast_packet->packet_type = BAT_UNICAST;
> - /* set unicast ttl */
> - unicast_packet->ttl = TTL;
> - /* copy the destination for faster routing */
> - memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
> - /* set the destination tt version number */
> - unicast_packet->ttvn =
> - (uint8_t)atomic_read(&orig_node->last_ttvn);
> -
> if (atomic_read(&bat_priv->fragmentation) &&
> data_len + sizeof(*unicast_packet) >
> neigh_node->if_incoming->net_dev->mtu) {
> @@ -350,7 +366,7 @@ out:
> neigh_node_free_ref(neigh_node);
> if (orig_node)
> orig_node_free_ref(orig_node);
> - if (ret == 1)
> + if (ret == 1 && skb)
> kfree_skb(skb);
> return ret;
> }
On Mon, Oct 31, 2011 at 01:05:46AM +0100, Simon Wunderlich wrote:
> On Sun, Oct 30, 2011 at 09:55:57AM +0100, Antonio Quartulli wrote:
> > -find_router:
> > +prepare_packet:
> > /**
> > * find_router():
>
> I guess the comment should be changed as well when the label is renamed.
Actually this comment refers to the function below, not to the label.
>
> > * - if orig_node is NULL it returns NULL
> > * - increases neigh_nodes refcount if found.
> > */
> > neigh_node = find_router(bat_priv, orig_node, NULL);
> > -
>
> Do we really need to remove this newline?
>
Don't think so ;)
Thanks,
@@ -283,6 +283,33 @@ out:
return ret;
}
+struct sk_buff *prepare_unicast_packet(struct sk_buff *skb,
+ struct orig_node *orig_node)
+{
+ struct unicast_packet *unicast_packet;
+
+ if (my_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
+ goto out;
+
+ unicast_packet = (struct unicast_packet *)skb->data;
+
+ unicast_packet->version = COMPAT_VERSION;
+ /* batman packet type: unicast */
+ unicast_packet->packet_type = BAT_UNICAST;
+ /* set unicast ttl */
+ unicast_packet->ttl = TTL;
+ /* copy the destination for faster routing */
+ memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
+ /* set the destination tt version number */
+ unicast_packet->ttvn =
+ (uint8_t)atomic_read(&orig_node->last_ttvn);
+
+ return skb;
+out:
+ kfree(skb);
+ return NULL;
+}
+
int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
{
struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
@@ -296,7 +323,7 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
if (is_multicast_ether_addr(ethhdr->h_dest)) {
orig_node = gw_get_selected_orig(bat_priv);
if (orig_node)
- goto find_router;
+ goto prepare_packet;
}
/* check for tt host - increases orig_node refcount.
@@ -304,33 +331,22 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
orig_node = transtable_search(bat_priv, ethhdr->h_source,
ethhdr->h_dest);
-find_router:
+prepare_packet:
/**
* find_router():
* - if orig_node is NULL it returns NULL
* - increases neigh_nodes refcount if found.
*/
neigh_node = find_router(bat_priv, orig_node, NULL);
-
if (!neigh_node)
goto out;
- if (my_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
+ skb = prepare_unicast_packet(skb, orig_node);
+ if (!skb)
goto out;
unicast_packet = (struct unicast_packet *)skb->data;
- unicast_packet->version = COMPAT_VERSION;
- /* batman packet type: unicast */
- unicast_packet->packet_type = BAT_UNICAST;
- /* set unicast ttl */
- unicast_packet->ttl = TTL;
- /* copy the destination for faster routing */
- memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
- /* set the destination tt version number */
- unicast_packet->ttvn =
- (uint8_t)atomic_read(&orig_node->last_ttvn);
-
if (atomic_read(&bat_priv->fragmentation) &&
data_len + sizeof(*unicast_packet) >
neigh_node->if_incoming->net_dev->mtu) {
@@ -350,7 +366,7 @@ out:
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
- if (ret == 1)
+ if (ret == 1 && skb)
kfree_skb(skb);
return ret;
}
@@ -33,6 +33,8 @@ void frag_list_free(struct list_head *head);
int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv);
int frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
struct hard_iface *hard_iface, const uint8_t dstaddr[]);
+struct sk_buff *prepare_unicast_packet(struct sk_buff *skb,
+ struct orig_node *orig_node);
static inline int frag_can_reassemble(const struct sk_buff *skb, int mtu)
{