On Mon, May 09, 2011 at 03:02:30PM +0200, Antonio Quartulli wrote:
If a client issues a DHCPREQUEST for renewal, the packet is dropped if the old destination (the old gateway for the client) TQ is smaller than the current best gateway TQ less GW_THRESHOLD
Signed-off-by: Antonio Quartulli ordex@autistici.org
gateway_client.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++++- gateway_client.h | 3 +- main.h | 3 +- soft-interface.c | 10 ++++- 4 files changed, 104 insertions(+), 6 deletions(-)
diff --git a/gateway_client.c b/gateway_client.c index 761dcfb..33bceee 100644 --- a/gateway_client.c +++ b/gateway_client.c @@ -25,11 +25,17 @@ #include "gateway_common.h" #include "hard-interface.h" #include "originator.h" +#include "routing.h" #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/udp.h> #include <linux/if_vlan.h>
+/* This is the offset of the options field in a dhcp packet starting at
- the beginning of the dhcp header */
+#define DHCP_OPTIONS_OFFSET 240 +#define DHCP_REQUEST 3
static void gw_node_free_rcu(struct rcu_head *rcu) { struct gw_node *gw_node; @@ -509,14 +515,75 @@ out: return ret; }
-int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb) +static bool is_type_dhcprequest(struct sk_buff *skb, int header_len) +{
- int ret = false;
- unsigned char *p;
- int pkt_len;
- if (skb_linearize(skb) < 0)
goto out;- pkt_len = skb_headlen(skb);
- if (pkt_len < header_len + DHCP_OPTIONS_OFFSET + 1)
goto out;- p = skb->data + header_len + DHCP_OPTIONS_OFFSET;
- pkt_len -= header_len + DHCP_OPTIONS_OFFSET + 1;
- /* Access the dhcp option lists. Each entry is made up by:
* - octect 1: option type* - octect 2: option data len (only if type != 255 and 0)* - octect 3: option data */- while (*p != 255 && !ret) {
/* p now points to the first octect: option type */if (*p == 53) {/* type 53 is the message type option.* Jump the len octect and go to the data octect */if (pkt_len < 2)goto out;pkt_len -= 2;p += 2;/* check if the message type is what we need */if (*p == DHCP_REQUEST)ret = true;
Why do you continue parsing the options if it is not a DHCP_REQUEST? Do you think there will be a second, third, fourth option information element 53?
Andrew