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Message-Id: <1322317612-7770-5-git-send-email-lindner_marek@yahoo.de>
Date: Sat, 26 Nov 2011 22:26:46 +0800
From: Marek Lindner <lindner_marek@...oo.de>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org, b.a.t.m.a.n@...ts.open-mesh.org,
Marek Lindner <lindner_marek@...oo.de>,
Sven Eckelmann <sven@...fation.org>
Subject: [PATCH 04/10] batman-adv: refactoring gateway handling code
Signed-off-by: Marek Lindner <lindner_marek@...oo.de>
Acked-by: Antonio Quartulli <ordex@...istici.org>
Signed-off-by: Sven Eckelmann <sven@...fation.org>
---
net/batman-adv/gateway_client.c | 157 ++++++++++++++++++++++++---------------
net/batman-adv/gateway_client.h | 5 +-
net/batman-adv/soft-interface.c | 43 +++++++----
3 files changed, 128 insertions(+), 77 deletions(-)
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 619fb73..9373a14 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -25,6 +25,7 @@
#include "gateway_common.h"
#include "hard-interface.h"
#include "originator.h"
+#include "translation-table.h"
#include "routing.h"
#include <linux/ip.h>
#include <linux/ipv6.h>
@@ -572,108 +573,142 @@ out:
return ret;
}
-int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb,
- struct orig_node *old_gw)
+bool gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len)
{
struct ethhdr *ethhdr;
struct iphdr *iphdr;
struct ipv6hdr *ipv6hdr;
struct udphdr *udphdr;
- struct gw_node *curr_gw;
- struct neigh_node *neigh_curr = NULL, *neigh_old = NULL;
- unsigned int header_len = 0;
- int ret = 1;
-
- if (atomic_read(&bat_priv->gw_mode) == GW_MODE_OFF)
- return 0;
/* check for ethernet header */
- if (!pskb_may_pull(skb, header_len + ETH_HLEN))
- return 0;
+ if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
+ return false;
ethhdr = (struct ethhdr *)skb->data;
- header_len += ETH_HLEN;
+ *header_len += ETH_HLEN;
/* check for initial vlan header */
if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
- if (!pskb_may_pull(skb, header_len + VLAN_HLEN))
- return 0;
+ if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
+ return false;
ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
- header_len += VLAN_HLEN;
+ *header_len += VLAN_HLEN;
}
/* check for ip header */
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_IP:
- if (!pskb_may_pull(skb, header_len + sizeof(*iphdr)))
- return 0;
- iphdr = (struct iphdr *)(skb->data + header_len);
- header_len += iphdr->ihl * 4;
+ if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
+ return false;
+ iphdr = (struct iphdr *)(skb->data + *header_len);
+ *header_len += iphdr->ihl * 4;
/* check for udp header */
if (iphdr->protocol != IPPROTO_UDP)
- return 0;
+ return false;
break;
case ETH_P_IPV6:
- if (!pskb_may_pull(skb, header_len + sizeof(*ipv6hdr)))
- return 0;
- ipv6hdr = (struct ipv6hdr *)(skb->data + header_len);
- header_len += sizeof(*ipv6hdr);
+ if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
+ return false;
+ ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
+ *header_len += sizeof(*ipv6hdr);
/* check for udp header */
if (ipv6hdr->nexthdr != IPPROTO_UDP)
- return 0;
+ return false;
break;
default:
- return 0;
+ return false;
}
- if (!pskb_may_pull(skb, header_len + sizeof(*udphdr)))
- return 0;
- udphdr = (struct udphdr *)(skb->data + header_len);
- header_len += sizeof(*udphdr);
+ if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
+ return false;
+ udphdr = (struct udphdr *)(skb->data + *header_len);
+ *header_len += sizeof(*udphdr);
/* check for bootp port */
if ((ntohs(ethhdr->h_proto) == ETH_P_IP) &&
(ntohs(udphdr->dest) != 67))
- return 0;
+ return false;
if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) &&
(ntohs(udphdr->dest) != 547))
- return 0;
-
- if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)
- return -1;
-
- curr_gw = gw_get_selected_gw_node(bat_priv);
- if (!curr_gw)
- return 0;
-
- /* If old_gw != NULL then this packet is unicast.
- * So, at this point we have to check the message type: if it is a
- * DHCPREQUEST we have to decide whether to drop it or not */
- if (old_gw && curr_gw->orig_node != old_gw) {
- if (is_type_dhcprequest(skb, header_len)) {
- /* If the dhcp packet has been sent to a different gw,
- * we have to evaluate whether the old gw is still
- * reliable enough */
- neigh_curr = find_router(bat_priv, curr_gw->orig_node,
- NULL);
- neigh_old = find_router(bat_priv, old_gw, NULL);
- if (!neigh_curr || !neigh_old)
- goto free_neigh;
- if (neigh_curr->tq_avg - neigh_old->tq_avg <
- GW_THRESHOLD)
- ret = -1;
- }
+ return false;
+
+ return true;
+}
+
+bool gw_out_of_range(struct bat_priv *bat_priv,
+ struct sk_buff *skb, struct ethhdr *ethhdr)
+{
+ struct neigh_node *neigh_curr = NULL, *neigh_old = NULL;
+ struct orig_node *orig_dst_node = NULL;
+ struct gw_node *curr_gw = NULL;
+ bool ret, out_of_range = false;
+ unsigned int header_len = 0;
+ uint8_t curr_tq_avg;
+
+ ret = gw_is_dhcp_target(skb, &header_len);
+ if (!ret)
+ goto out;
+
+ orig_dst_node = transtable_search(bat_priv, ethhdr->h_source,
+ ethhdr->h_dest);
+ if (!orig_dst_node)
+ goto out;
+
+ if (!orig_dst_node->gw_flags)
+ goto out;
+
+ ret = is_type_dhcprequest(skb, header_len);
+ if (!ret)
+ goto out;
+
+ switch (atomic_read(&bat_priv->gw_mode)) {
+ case GW_MODE_SERVER:
+ /* If we are a GW then we are our best GW. We can artificially
+ * set the tq towards ourself as the maximum value */
+ curr_tq_avg = TQ_MAX_VALUE;
+ break;
+ case GW_MODE_CLIENT:
+ curr_gw = gw_get_selected_gw_node(bat_priv);
+ if (!curr_gw)
+ goto out;
+
+ /* packet is going to our gateway */
+ if (curr_gw->orig_node == orig_dst_node)
+ goto out;
+
+ /* If the dhcp packet has been sent to a different gw,
+ * we have to evaluate whether the old gw is still
+ * reliable enough */
+ neigh_curr = find_router(bat_priv, curr_gw->orig_node, NULL);
+ if (!neigh_curr)
+ goto out;
+
+ curr_tq_avg = neigh_curr->tq_avg;
+ break;
+ case GW_MODE_OFF:
+ default:
+ goto out;
}
-free_neigh:
+
+ neigh_old = find_router(bat_priv, orig_dst_node, NULL);
+ if (!!neigh_old)
+ goto out;
+
+ if (curr_tq_avg - neigh_old->tq_avg > GW_THRESHOLD)
+ out_of_range = true;
+
+out:
+ if (orig_dst_node)
+ orig_node_free_ref(orig_dst_node);
+ if (curr_gw)
+ gw_node_free_ref(curr_gw);
if (neigh_old)
neigh_node_free_ref(neigh_old);
if (neigh_curr)
neigh_node_free_ref(neigh_curr);
- if (curr_gw)
- gw_node_free_ref(curr_gw);
- return ret;
+ return out_of_range;
}
diff --git a/net/batman-adv/gateway_client.h b/net/batman-adv/gateway_client.h
index b9b983c..e1edba0 100644
--- a/net/batman-adv/gateway_client.h
+++ b/net/batman-adv/gateway_client.h
@@ -31,7 +31,8 @@ void gw_node_update(struct bat_priv *bat_priv,
void gw_node_delete(struct bat_priv *bat_priv, struct orig_node *orig_node);
void gw_node_purge(struct bat_priv *bat_priv);
int gw_client_seq_print_text(struct seq_file *seq, void *offset);
-int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb,
- struct orig_node *old_gw);
+bool gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len);
+bool gw_out_of_range(struct bat_priv *bat_priv,
+ struct sk_buff *skb, struct ethhdr *ethhdr);
#endif /* _NET_BATMAN_ADV_GATEWAY_CLIENT_H_ */
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index f9cc957..45297c8 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -563,10 +563,10 @@ static int interface_tx(struct sk_buff *skb, struct net_device *soft_iface)
struct bcast_packet *bcast_packet;
struct vlan_ethhdr *vhdr;
struct softif_neigh *curr_softif_neigh = NULL;
- struct orig_node *orig_node = NULL;
+ unsigned int header_len = 0;
int data_len = skb->len, ret;
short vid = -1;
- bool do_bcast;
+ bool do_bcast = false;
if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
goto dropped;
@@ -598,17 +598,28 @@ static int interface_tx(struct sk_buff *skb, struct net_device *soft_iface)
/* Register the client MAC in the transtable */
tt_local_add(soft_iface, ethhdr->h_source, skb->skb_iif);
- orig_node = transtable_search(bat_priv, ethhdr->h_source,
- ethhdr->h_dest);
- do_bcast = is_multicast_ether_addr(ethhdr->h_dest);
- if (do_bcast || (orig_node && orig_node->gw_flags)) {
- ret = gw_is_target(bat_priv, skb, orig_node);
+ if (is_multicast_ether_addr(ethhdr->h_dest)) {
+ do_bcast = true;
- if (ret < 0)
- goto dropped;
-
- if (ret)
- do_bcast = false;
+ switch (atomic_read(&bat_priv->gw_mode)) {
+ case GW_MODE_SERVER:
+ /* gateway servers should not send dhcp
+ * requests into the mesh */
+ ret = gw_is_dhcp_target(skb, &header_len);
+ if (ret)
+ goto dropped;
+ break;
+ case GW_MODE_CLIENT:
+ /* gateway clients should send dhcp requests
+ * via unicast to their gateway */
+ ret = gw_is_dhcp_target(skb, &header_len);
+ if (ret)
+ do_bcast = false;
+ break;
+ case GW_MODE_OFF:
+ default:
+ break;
+ }
}
/* ethernet packet should be broadcasted */
@@ -644,6 +655,12 @@ static int interface_tx(struct sk_buff *skb, struct net_device *soft_iface)
/* unicast packet */
} else {
+ if (atomic_read(&bat_priv->gw_mode) != GW_MODE_OFF) {
+ ret = gw_out_of_range(bat_priv, skb, ethhdr);
+ if (ret)
+ goto dropped;
+ }
+
ret = unicast_send_skb(skb, bat_priv);
if (ret != 0)
goto dropped_freed;
@@ -662,8 +679,6 @@ end:
softif_neigh_free_ref(curr_softif_neigh);
if (primary_if)
hardif_free_ref(primary_if);
- if (orig_node)
- orig_node_free_ref(orig_node);
return NETDEV_TX_OK;
}
--
1.7.5.4
--
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