* [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation
@ 2016-07-02 4:09 Linus Lüssing
2016-07-02 4:09 ` [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT Linus Lüssing
2016-07-02 7:40 ` [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Sven Eckelmann
0 siblings, 2 replies; 4+ messages in thread
From: Linus Lüssing @ 2016-07-02 4:09 UTC (permalink / raw)
To: b.a.t.m.a.n
Removing duplicate code.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
Changes in RFC -> non-RFC:
* Added kerneldoc
* Added Signed-off-by
net/batman-adv/distributed-arp-table.c | 61 ++++++++++++++++++++++------------
1 file changed, 40 insertions(+), 21 deletions(-)
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index fa76465..66114af 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -948,6 +948,41 @@ static unsigned short batadv_dat_get_vid(struct sk_buff *skb, int *hdr_size)
}
/**
+ * batadv_dat_arp_create_reply - create an ARP Reply
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ip_src: ARP sender IP
+ * @ip_dst: ARP target IP
+ * @hw_src: Ethernet source and ARP sender MAC
+ * @hw_dst: Ethernet destination and ARP target MAC
+ * @vid: VLAN identifier (optional, set to zero otherwise)
+ *
+ * Creates an ARP Reply from the given values, optionally encapsulated in a
+ * VLAN header.
+ *
+ * Return: An skb containing an ARP Reply.
+ */
+static struct sk_buff *
+batadv_dat_arp_create_reply(struct batadv_priv *bat_priv, __be32 ip_src,
+ __be32 ip_dst, u8 *hw_src, u8 *hw_dst,
+ unsigned short vid)
+{
+ struct sk_buff *skb;
+
+ skb = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_dst, bat_priv->soft_iface,
+ ip_src, hw_dst, hw_src, hw_dst);
+ if (!skb)
+ return NULL;
+
+ if (vid & BATADV_VLAN_HAS_TAG)
+ skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
+ vid & VLAN_VID_MASK);
+
+ skb_reset_mac_header(skb);
+
+ return skb;
+}
+
+/**
* batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to
* answer using DAT
* @bat_priv: the bat priv with all the soft interface information
@@ -1005,17 +1040,12 @@ bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
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);
+ skb_new = batadv_dat_arp_create_reply(bat_priv, ip_dst, ip_src,
+ dat_entry->mac_addr,
+ hw_src, vid);
if (!skb_new)
goto out;
- if (vid & BATADV_VLAN_HAS_TAG)
- skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
- vid & VLAN_VID_MASK);
-
- skb_reset_mac_header(skb_new);
skb_new->protocol = eth_type_trans(skb_new,
bat_priv->soft_iface);
bat_priv->stats.rx_packets++;
@@ -1079,22 +1109,11 @@ bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
if (!dat_entry)
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);
-
+ skb_new = batadv_dat_arp_create_reply(bat_priv, ip_dst, ip_src,
+ dat_entry->mac_addr, hw_src, vid);
if (!skb_new)
goto out;
- /* the rest of the TX path assumes that the mac_header offset pointing
- * to the inner Ethernet header has been set, therefore reset it now.
- */
- skb_reset_mac_header(skb_new);
-
- if (vid & BATADV_VLAN_HAS_TAG)
- skb_new = vlan_insert_tag(skb_new, htons(ETH_P_8021Q),
- vid & VLAN_VID_MASK);
-
/* To preserve backwards compatibility, the node has choose the outgoing
* format based on the incoming request packet type. The assumption is
* that a node not using the 4addr packet format doesn't support it.
--
2.1.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT
2016-07-02 4:09 [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Linus Lüssing
@ 2016-07-02 4:09 ` Linus Lüssing
2016-07-02 7:18 ` Sven Eckelmann
2016-07-02 7:40 ` [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Sven Eckelmann
1 sibling, 1 reply; 4+ messages in thread
From: Linus Lüssing @ 2016-07-02 4:09 UTC (permalink / raw)
To: b.a.t.m.a.n
In a typical mesh network, when a new client connects then it will
usually first try to grab an IPv4 address via DHCP. Afterwards in
public mesh networks a client will try to contact the internet over
the server.
While the IPv4 address of the DHCP-Server is usually well propagated
in the DHT, the IPv4 address of a newly joining client is not.
This can lead to a considerable amount of ARP broadcasts not caught
by DAT from the servers.
In a 1000 nodes mesh network (Freifunk Hamburg) we can still see
30KBit/s of ARP traffic (equalling about 25% of all layer two
specific overhead, remaining after some filtering) flooded through
the mesh. These 30KBit/s are mainly ARP Requests from the
gateways / DHCP servers.
Through snooping DHCPACKs we can actually learn about MAC/IP address
pairs without the need of any flooded ARP messages in advance. This
allows servers to fill their local DAT cache with according entries
before any communciation with a client can possibly have taken place.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
Changes in RFC -> non-RFC
* Added kerneldoc
* Added Signed-off-by
* More IP Header checks
(iph->hlen considered, ip version checked, ...)
* Parsing & checking DHCP Message Type Option,
only snooping DHCPACKs now
* Moved ethernet protocol check from batadv_dat_check_dhcp to
batadv_dat_check_dhcp_ipudp
* Removed buffer-length parameter from
batadv_dat_dhcp_get_{yiaddr,chaddr}()
* Renamed batadv_dat_put() to batadv_dat_put_pairs()
net/batman-adv/distributed-arp-table.c | 297 +++++++++++++++++++++++++++++++++
net/batman-adv/distributed-arp-table.h | 4 +
net/batman-adv/packet.h | 48 ++++++
net/batman-adv/soft-interface.c | 11 +-
4 files changed, 358 insertions(+), 2 deletions(-)
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index 66114af..3a66d4b 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -28,6 +28,7 @@
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/in.h>
+#include <linux/ip.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
@@ -40,8 +41,10 @@
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
+#include <linux/udp.h>
#include <linux/workqueue.h>
#include <net/arp.h>
+#include <net/ip.h>
#include "hard-interface.h"
#include "hash.h"
@@ -973,6 +976,8 @@ batadv_dat_arp_create_reply(struct batadv_priv *bat_priv, __be32 ip_src,
if (!skb)
return NULL;
+ skb_set_network_header(skb, ETH_HLEN);
+
if (vid & BATADV_VLAN_HAS_TAG)
skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
vid & VLAN_VID_MASK);
@@ -1237,6 +1242,298 @@ out:
}
/**
+ * batadv_dat_check_dhcp_ipudp - check skb for IP+UDP headers valid for DHCP
+ * @skb: the packet to check
+ * @proto: ethernet protocol hint (behind a potential vlan)
+ *
+ * Checks whether the given skb has an IP and UDP header valid for a DHCP
+ * message from a DHCP server.
+ *
+ * Return: True if valid, false otherwise.
+ */
+static bool batadv_dat_check_dhcp_ipudp(struct sk_buff *skb)
+{
+ struct iphdr *iphdr, _iphdr;
+ struct udphdr *udphdr, _udphdr;
+ unsigned int offset = skb_network_offset(skb);
+
+ iphdr = skb_header_pointer(skb, offset, sizeof(_iphdr), &_iphdr);
+ if (!iphdr || iphdr->version != 4 || ip_hdrlen(skb) < sizeof(_iphdr))
+ return false;
+
+ if (iphdr->protocol != IPPROTO_UDP)
+ return false;
+
+ offset += ip_hdrlen(skb);
+ skb_set_transport_header(skb, offset);
+
+ udphdr = skb_header_pointer(skb, offset, sizeof(_udphdr), &_udphdr);
+ if (!udphdr || udphdr->source != htons(67))
+ return false;
+
+ return true;
+}
+
+/**
+ * batadv_dat_check_dhcp - examine packet for valid DHCP message
+ * @skb: the packet to check
+ * @proto: ethernet protocol hint (behind a potential vlan)
+ *
+ * Checks whether the given skb is a valid DHCP packet.
+ *
+ * Caller needs to ensure that the skb network header is set correctly.
+ *
+ * Return: If skb is a valid DHCP packet, then returns its op code
+ * (e.g. BOOTREPLY vs. BOOTREQUEST). Otherwise returns -EINVAL.
+ */
+static int batadv_dat_check_dhcp(struct sk_buff *skb, __be16 proto)
+{
+ u8 *op, _op;
+ u8 *htype, _htype;
+ u8 *hlen, _hlen;
+ __be32 *magic, _magic;
+ unsigned int dhcp_offset;
+ unsigned int offset;
+
+ if (proto != htons(ETH_P_IP))
+ return -EINVAL;
+
+ if (!batadv_dat_check_dhcp_ipudp(skb))
+ return -EINVAL;
+
+ dhcp_offset = skb_transport_offset(skb) + sizeof(struct udphdr);
+ if (skb->len < dhcp_offset + sizeof(struct batadv_dhcp_packet))
+ return -EINVAL;
+
+ offset = dhcp_offset + offsetof(struct batadv_dhcp_packet, op);
+
+ op = skb_header_pointer(skb, offset, sizeof(_op), &_op);
+ if (!op)
+ return -EINVAL;
+
+ offset = dhcp_offset + offsetof(struct batadv_dhcp_packet, htype);
+
+ htype = skb_header_pointer(skb, offset, sizeof(_htype), &_htype);
+ if (!htype || *htype != BATADV_HTYPE_ETHERNET)
+ return -EINVAL;
+
+ offset = dhcp_offset + offsetof(struct batadv_dhcp_packet, hlen);
+
+ hlen = skb_header_pointer(skb, offset, sizeof(_hlen), &_hlen);
+ if (!hlen || *hlen != ETH_ALEN)
+ return -EINVAL;
+
+ offset = dhcp_offset + offsetof(struct batadv_dhcp_packet, magic);
+
+ magic = skb_header_pointer(skb, offset, sizeof(_magic), &_magic);
+ if (!magic || *magic != htonl(BATADV_DHCP_MAGIC))
+ return -EINVAL;
+
+ return *op;
+}
+
+/**
+ * batadv_dat_get_dhcp_message_type - get message type of a DHCP packet
+ * @skb: the DHCP packet to parse
+ *
+ * Iterates over the DHCP options of the given DHCP packet to find a
+ * DHCP Message Type option and parse it.
+ *
+ * Caller needs to ensure that the given skb is a valid DHCP packet and
+ * that the skb transport header is set correctly.
+ *
+ * Return: The found DHCP message type value, if found. -EINVAL otherwise.
+ */
+static int batadv_dat_get_dhcp_message_type(struct sk_buff *skb)
+{
+ unsigned int offset = skb_transport_offset(skb) + sizeof(struct udphdr);
+ u8 *type, _type;
+ struct {
+ u8 type;
+ u8 len;
+ } *tl, _tl;
+
+ offset += sizeof(struct batadv_dhcp_packet);
+
+ while ((tl = skb_header_pointer(skb, offset, sizeof(_tl), &_tl))) {
+ if (tl->type == BATADV_DHCP_OPT_MSG_TYPE)
+ break;
+
+ if (tl->type == BATADV_DHCP_OPT_END)
+ break;
+
+ if (tl->type == BATADV_DHCP_OPT_PAD)
+ offset++;
+ else
+ offset += tl->len + sizeof(_tl);
+ }
+
+ /* Option Overload Code not supported */
+ if (!tl || tl->type != BATADV_DHCP_OPT_MSG_TYPE ||
+ tl->len != sizeof(_type))
+ return -EINVAL;
+
+ offset += sizeof(_tl);
+
+ type = skb_header_pointer(skb, offset, sizeof(_type), &_type);
+ if (!type)
+ return -EINVAL;
+
+ return *type;
+}
+
+/**
+ * batadv_dat_get_dhcp_yiaddr - get yiaddr from a DHCP packet
+ * @skb: the DHCP packet to parse
+ * @buffer: a buffer to store the yiaddr in (if necessary / skb is non-linear)
+ *
+ * Caller needs to ensure that the given skb is a valid DHCP packet and
+ * that the skb transport header is set correctly.
+ *
+ * Return: A safely accessible "Your IP Address" field from the provided DHCP
+ * packet.
+ */
+static __be32 *batadv_dat_dhcp_get_yiaddr(struct sk_buff *skb, __be32 *buffer)
+{
+ unsigned int offset = skb_transport_offset(skb) + sizeof(struct udphdr);
+ unsigned int len = sizeof(((struct batadv_dhcp_packet *)0)->yiaddr);
+
+ offset += offsetof(struct batadv_dhcp_packet, yiaddr);
+
+ return skb_header_pointer(skb, offset, len, buffer);
+}
+
+/**
+ * batadv_dat_get_dhcp_chaddr - get chaddr from a DHCP packet
+ * @skb: the DHCP packet to parse
+ * @buffer: a buffer to store the chaddr in (if necessary / skb is non-linear)
+ *
+ * Caller needs to ensure that the given skb is a valid DHCP packet and
+ * that the skb transport header is set correctly.
+ *
+ * Return: A safely accessible "Client Hardware Address" field from the provided
+ * DHCP packet.
+ */
+static u8 *batadv_dat_get_dhcp_chaddr(struct sk_buff *skb, u8 *buffer)
+{
+ unsigned int offset = skb_transport_offset(skb) + sizeof(struct udphdr);
+ unsigned int len = sizeof(((struct batadv_dhcp_packet *)0)->chaddr);
+
+ offset += offsetof(struct batadv_dhcp_packet, chaddr);
+
+ return skb_header_pointer(skb, offset, len, buffer);
+}
+
+/**
+ * batadv_dat_put_pairs - puts two MAC/IP pairs into the DHT and DAT cache
+ * @bat_priv: the bat priv with all the soft interface information
+ * @hw_src: first value of DHT and ARP sender MAC
+ * @ip_src: first key of DHT and ARP sender IP
+ * @hw_dst: second value of DHT and ARP target MAC
+ * @ip_dst: second key of DHT and ARP target IP
+ * @vid: VLAN identifier
+ *
+ * First checks whether the given MAC/IP pairs are suitable for DAT. If so, adds
+ * them to the local DAT cache and propagates them further into the DHT.
+ *
+ * For the DHT propagation, hw_src/ip_src will appear as the ARP Reply
+ * transmitter (and hw_dst/ip_dst as the target).
+ *
+ * Return: True on success, false otherwise.
+ */
+static bool batadv_dat_put_pairs(struct batadv_priv *bat_priv, u8 *hw_src,
+ __be32 ip_src, u8 *hw_dst, __be32 ip_dst,
+ unsigned short vid)
+{
+ struct sk_buff *skb;
+ int hdr_size;
+ u16 type;
+ int ret = false;
+
+ skb = batadv_dat_arp_create_reply(bat_priv, ip_src, ip_dst, hw_src,
+ hw_dst, vid);
+ if (!skb)
+ return false;
+
+ /* Check for validity of provided addresses */
+ hdr_size = skb_network_offset(skb) - ETH_HLEN;
+ type = batadv_arp_get_type(bat_priv, skb, hdr_size);
+ if (type != ARPOP_REPLY)
+ goto err_skip_commit;
+
+ batadv_dat_entry_add(bat_priv, ip_src, hw_src, vid);
+ batadv_dat_entry_add(bat_priv, ip_dst, hw_dst, vid);
+
+ batadv_dat_send_data(bat_priv, skb, ip_src, vid, BATADV_P_DAT_DHT_PUT);
+ batadv_dat_send_data(bat_priv, skb, ip_dst, vid, BATADV_P_DAT_DHT_PUT);
+
+ ret = true;
+
+err_skip_commit:
+ dev_kfree_skb(skb);
+ return ret;
+}
+
+/**
+ * batadv_dat_snoop_outgoing_dhcp_ack - snoop DHCPACK and fill DAT with it
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the packet to snoop
+ * @proto: ethernet protocol hint (behind a potential vlan)
+ * @vid: VLAN identifier
+ *
+ * This function first checks whether the given skb is a valid DHCPACK. If
+ * so then its source MAC and IP as well as its DHCP Client Hardware Address
+ * field and DHCP Your IP Address field are added to the local DAT cache and
+ * propagated into the DHT.
+ *
+ * Caller needs to ensure that the skb mac and network headers are set
+ * correctly.
+ */
+void batadv_dat_snoop_outgoing_dhcp_ack(struct batadv_priv *bat_priv,
+ struct sk_buff *skb,
+ __be16 proto,
+ unsigned short vid)
+{
+ int type;
+ u8 *chaddr, _chaddr[ETH_ALEN];
+ __be32 *yiaddr, _yiaddr;
+
+ if (!atomic_read(&bat_priv->distributed_arp_table))
+ return;
+
+ if (batadv_dat_check_dhcp(skb, proto) != BATADV_BOOTREPLY)
+ return;
+
+ type = batadv_dat_get_dhcp_message_type(skb);
+ if (type != BATADV_DHCPACK)
+ return;
+
+ yiaddr = batadv_dat_dhcp_get_yiaddr(skb, &_yiaddr);
+ if (!yiaddr)
+ return;
+
+ chaddr = batadv_dat_get_dhcp_chaddr(skb, _chaddr);
+ if (!chaddr)
+ return;
+
+ /* ARP sender MAC + IP -> DHCP Client (chaddr+yiaddr),
+ * ARP target MAC + IP -> DHCP Server (ethhdr/iphdr sources)
+ */
+ if (!batadv_dat_put_pairs(bat_priv, chaddr, *yiaddr,
+ eth_hdr(skb)->h_source, ip_hdr(skb)->saddr,
+ vid))
+ return;
+
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
+ "Snooped from DHCPACK (server-side): %pI4, %pM (vid: %i)\n",
+ &ip_hdr(skb)->saddr, eth_hdr(skb)->h_source,
+ BATADV_PRINT_VID(vid));
+ batadv_dbg(BATADV_DBG_DAT, bat_priv,
+ "Snooped from DHCPACK (client-side): %pI4, %pM (vid: %i)\n",
+ yiaddr, chaddr, BATADV_PRINT_VID(vid));
+}
+
+/**
* batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped
* (because the node has already obtained the reply via DAT) or not
* @bat_priv: the bat priv with all the soft interface information
diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h
index 813ecea..c81234c 100644
--- a/net/batman-adv/distributed-arp-table.h
+++ b/net/batman-adv/distributed-arp-table.h
@@ -44,6 +44,10 @@ void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
struct sk_buff *skb);
bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
struct sk_buff *skb, int hdr_size);
+void batadv_dat_snoop_outgoing_dhcp_ack(struct batadv_priv *bat_priv,
+ struct sk_buff *skb,
+ __be16 proto,
+ unsigned short vid);
bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
struct batadv_forw_packet *forw_packet);
diff --git a/net/batman-adv/packet.h b/net/batman-adv/packet.h
index 6b011ff..d8afbfa 100644
--- a/net/batman-adv/packet.h
+++ b/net/batman-adv/packet.h
@@ -664,4 +664,52 @@ struct batadv_tvlv_mcast_data {
u8 reserved[3];
};
+enum batadv_bootpop {
+ BATADV_BOOTREQUEST = 1,
+ BATADV_BOOTREPLY = 2,
+};
+
+enum batadv_boothtype {
+ BATADV_HTYPE_ETHERNET = 1,
+};
+
+enum batadv_dhcpoptioncode {
+ BATADV_DHCP_OPT_PAD = 0,
+ BATADV_DHCP_OPT_MSG_TYPE = 53,
+ BATADV_DHCP_OPT_END = 255,
+};
+
+enum batadv_dhcptype {
+ BATADV_DHCPDISCOVER = 1,
+ BATADV_DHCPOFFER = 2,
+ BATADV_DHCPREQUEST = 3,
+ BATADV_DHCPDECLINE = 4,
+ BATADV_DHCPACK = 5,
+ BATADV_DHCPNAK = 6,
+ BATADV_DHCPRELEASE = 7,
+ BATADV_DHCPINFORM = 8,
+};
+
+/* { 99, 130, 83, 99 } */
+#define BATADV_DHCP_MAGIC 1669485411
+
+struct batadv_dhcp_packet {
+ u8 op;
+ u8 htype;
+ u8 hlen;
+ u8 hops;
+ __be32 xid;
+ __be16 secs;
+ __be16 flags;
+ __be32 ciaddr;
+ __be32 yiaddr;
+ __be32 siaddr;
+ __be32 giaddr;
+ u8 chaddr[16];
+ u8 sname[64];
+ u8 file[128];
+ __be32 magic;
+ u8 options[0];
+};
+
#endif /* _NET_BATMAN_ADV_PACKET_H_ */
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 216ac03..12bc41b 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -204,6 +204,7 @@ static int batadv_interface_tx(struct sk_buff *skb,
enum batadv_forw_mode forw_mode;
struct batadv_orig_node *mcast_single_orig = NULL;
int network_offset = ETH_HLEN;
+ __be16 proto;
if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
goto dropped;
@@ -212,12 +213,15 @@ static int batadv_interface_tx(struct sk_buff *skb,
vid = batadv_get_vid(skb, 0);
ethhdr = eth_hdr(skb);
- switch (ntohs(ethhdr->h_proto)) {
+ proto = ethhdr->h_proto;
+
+ switch (ntohs(proto)) {
case ETH_P_8021Q:
vhdr = vlan_eth_hdr(skb);
+ proto = vhdr->h_vlan_encapsulated_proto;
/* drop batman-in-batman packets to prevent loops */
- if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN)) {
+ if (proto != htons(ETH_P_BATMAN)) {
network_offset += VLAN_HLEN;
break;
}
@@ -244,6 +248,9 @@ static int batadv_interface_tx(struct sk_buff *skb,
goto dropped;
}
+ /* Snoop address candidates from DHCPACKs for early DAT filling */
+ batadv_dat_snoop_outgoing_dhcp_ack(bat_priv, skb, proto, vid);
+
/* don't accept stp packets. STP does not help in meshes.
* better use the bridge loop avoidance ...
*
--
2.1.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT
2016-07-02 4:09 ` [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT Linus Lüssing
@ 2016-07-02 7:18 ` Sven Eckelmann
0 siblings, 0 replies; 4+ messages in thread
From: Sven Eckelmann @ 2016-07-02 7:18 UTC (permalink / raw)
To: b.a.t.m.a.n
[-- Attachment #1: Type: text/plain, Size: 3616 bytes --]
Hi,
Haven't looked at the patch itself but it doesn't seem to compile (see
the CONFIG_* options):
/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/gen-compat-autoconf.sh /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/compat-autoconf.h
/usr/bin/make -C /home/sven/projekte/build_test/linux-build//linux-4.6 M=/home/sven/projekte/build_test/tmp.ZCzmUfnk6m PWD=/home/sven/projekte/build_test/tmp.ZCzmUfnk6m REVISION= CONFIG_BATMAN_ADV=m CONFIG_BATMAN_ADV_DEBUG=n CONFIG_BATMAN_ADV_BLA=n CONFIG_BATMAN_ADV_DAT=n CONFIG_BATMAN_ADV_NC=y CONFIG_BATMAN_ADV_MCAST=n CONFIG_BATMAN_ADV_BATMAN_V=n INSTALL_MOD_DIR=updates/ modules
make[1]: Entering directory '/home/sven/projekte/build_test/linux-build/linux-4.6'
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/bat_algo.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/bat_iv_ogm.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/bitarray.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/debugfs.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/fragmentation.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/gateway_client.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/gateway_common.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/hard-interface.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/hash.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/icmp_socket.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/main.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/netlink.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/network-coding.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/originator.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/routing.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/send.o
CC [M] /home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.o
scripts/Makefile.build:291: recipe for target '/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.o' failed
scripts/Makefile.build:440: recipe for target '/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv' failed
Makefile:1428: recipe for target '_module_/home/sven/projekte/build_test/tmp.ZCzmUfnk6m' failed
make[1]: Leaving directory '/home/sven/projekte/build_test/linux-build/linux-4.6'
Makefile:77: recipe for target 'all' failed
/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.c:252:9: error: undefined identifier 'batadv_dat_snoop_outgoing_dhcp_ack'
/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.c: In function 'batadv_interface_tx':
/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.c:252:2: error: implicit declaration of function 'batadv_dat_snoop_outgoing_dhcp_ack' [-Werror=implicit-function-declaration]
batadv_dat_snoop_outgoing_dhcp_ack(bat_priv, skb, proto, vid);
^
cc1: some warnings being treated as errors
make[3]: *** [/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv/soft-interface.o] Error 1
make[2]: *** [/home/sven/projekte/build_test/tmp.ZCzmUfnk6m/net/batman-adv] Error 2
make[1]: *** [_module_/home/sven/projekte/build_test/tmp.ZCzmUfnk6m] Error 2
make: *** [all] Error 2
Kind regards,
Sven
[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation
2016-07-02 4:09 [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Linus Lüssing
2016-07-02 4:09 ` [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT Linus Lüssing
@ 2016-07-02 7:40 ` Sven Eckelmann
1 sibling, 0 replies; 4+ messages in thread
From: Sven Eckelmann @ 2016-07-02 7:40 UTC (permalink / raw)
To: b.a.t.m.a.n
[-- Attachment #1: Type: text/plain, Size: 997 bytes --]
On Saturday 02 July 2016 06:09:50 Linus Lüssing wrote:
[...]
> +
> + if (vid & BATADV_VLAN_HAS_TAG)
> + skb = vlan_insert_tag(skb, htons(ETH_P_8021Q),
> + vid & VLAN_VID_MASK);
> +
> + skb_reset_mac_header(skb);
> +
> + return skb;
> +}
vlan_insert_tag can return NULL when an error happens. Thus simply doing
a skb_reset_mac_header on it without checking skb's value for !NULL is a
bad idea.
But you can simply move the skb_reset_mac_header (when it is really
necessary) in front of the 'if (vid & BATADV_VLAN_HAS_TAG)'.
Doing it in front would result in (written as absolute values - in
reality mac_header is an offset):
skb->mac_header = skb->data
skb->data -= VLAN_HLEN
skb->mac_header -= VLAN_HLEN
Writing it after the vlan_insert_tag would result in:
skb->data -= VLAN_HLEN
skb->mac_header -= VLAN_HLEN
skb->mac_header = skb->data
Both calculations should result in skb->mac_header == skb->data
Kind regards,
Sven
[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-07-02 7:40 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-07-02 4:09 [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Linus Lüssing
2016-07-02 4:09 ` [B.A.T.M.A.N.] [PATCH 2/2] batman-adv: Snoop DHCPACKs for DAT Linus Lüssing
2016-07-02 7:18 ` Sven Eckelmann
2016-07-02 7:40 ` [B.A.T.M.A.N.] [PATCH 1/2] batman-adv: Add wrapper for ARP reply creation Sven Eckelmann
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).