Commit 3c5772a5 authored by Javier Cardona's avatar Javier Cardona Committed by John W. Linville

mac80211: Use 3-address format for mesh broadcast frames.

The 11s task group recently changed the frame mesh multicast/broadcast frame
format to use 3-address.  This was done to avoid interactions with widely
deployed lazy-WDS access points.

This patch changes the format of group addressed frames, both mesh-originated
and proxied, to use the data format defined in draft D2.08 and forward.  The
address fields used for group addressed frames is:

In 802.11 header
 ToDS:0  FromDS:1
 addr1: DA  (broadcast/multicast address)
 addr2: TA
 addr3: Mesh SA

In address extension header:
 addr4: SA  (only present if frame was proxied)

Note that this change breaks backward compatibility with earlier mesh stack
versions.
Signed-off-by: default avatarAndrey Yurovsky <andrey@cozybit.com>
Signed-off-by: default avatarJavier Cardona <javier@cozybit.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent a9e3091b
......@@ -398,22 +398,76 @@ endgrow:
return NULL;
}
/**
* ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
* @hdr: 802.11 frame header
* @fc: frame control field
* @meshda: destination address in the mesh
* @meshsa: source address address in the mesh. Same as TA, as frame is
* locally originated.
*
* Return the length of the 802.11 (does not include a mesh control header)
*/
int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc, char
*meshda, char *meshsa) {
if (is_multicast_ether_addr(meshda)) {
*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
/* DA TA SA */
memcpy(hdr->addr1, meshda, ETH_ALEN);
memcpy(hdr->addr2, meshsa, ETH_ALEN);
memcpy(hdr->addr3, meshsa, ETH_ALEN);
return 24;
} else {
*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
IEEE80211_FCTL_TODS);
/* RA TA DA SA */
memset(hdr->addr1, 0, ETH_ALEN); /* RA is resolved later */
memcpy(hdr->addr2, meshsa, ETH_ALEN);
memcpy(hdr->addr3, meshda, ETH_ALEN);
memcpy(hdr->addr4, meshsa, ETH_ALEN);
return 30;
}
}
/**
* ieee80211_new_mesh_header - create a new mesh header
* @meshhdr: uninitialized mesh header
* @sdata: mesh interface to be used
* @addr4: addr4 of the mesh frame (1st in ae header)
* may be NULL
* @addr5: addr5 of the mesh frame (1st or 2nd in ae header)
* may be NULL unless addr6 is present
* @addr6: addr6 of the mesh frame (2nd or 3rd in ae header)
* may be NULL unless addr5 is present
*
* Return the header length.
*/
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
struct ieee80211_sub_if_data *sdata)
struct ieee80211_sub_if_data *sdata, char *addr4,
char *addr5, char *addr6)
{
meshhdr->flags = 0;
int aelen = 0;
memset(meshhdr, 0, sizeof(meshhdr));
meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
sdata->u.mesh.mesh_seqnum++;
return 6;
if (addr4) {
meshhdr->flags |= MESH_FLAGS_AE_A4;
aelen += ETH_ALEN;
memcpy(meshhdr->eaddr1, addr4, ETH_ALEN);
}
if (addr5 && addr6) {
meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
aelen += 2 * ETH_ALEN;
if (!addr4) {
memcpy(meshhdr->eaddr1, addr5, ETH_ALEN);
memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
} else {
memcpy(meshhdr->eaddr2, addr5, ETH_ALEN);
memcpy(meshhdr->eaddr3, addr6, ETH_ALEN);
}
}
return 6 + aelen;
}
static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata,
......
......@@ -193,8 +193,11 @@ struct mesh_rmc {
/* Public interfaces */
/* Various */
int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
char *da, char *sa);
int ieee80211_new_mesh_header(struct ieee80211s_hdr *meshhdr,
struct ieee80211_sub_if_data *sdata);
struct ieee80211_sub_if_data *sdata, char *addr4,
char *addr5, char *addr6);
int mesh_rmc_check(u8 *addr, struct ieee80211s_hdr *mesh_hdr,
struct ieee80211_sub_if_data *sdata);
bool mesh_matches_local(struct ieee802_11_elems *ie,
......
......@@ -489,12 +489,21 @@ ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
unsigned int hdrlen = ieee80211_hdrlen(hdr->frame_control);
char *dev_addr = rx->dev->dev_addr;
if (ieee80211_is_data(hdr->frame_control)) {
if (!ieee80211_has_a4(hdr->frame_control))
return RX_DROP_MONITOR;
if (memcmp(hdr->addr4, rx->dev->dev_addr, ETH_ALEN) == 0)
return RX_DROP_MONITOR;
if (is_multicast_ether_addr(hdr->addr1)) {
if (ieee80211_has_tods(hdr->frame_control) ||
!ieee80211_has_fromds(hdr->frame_control))
return RX_DROP_MONITOR;
if (memcmp(hdr->addr3, dev_addr, ETH_ALEN) == 0)
return RX_DROP_MONITOR;
} else {
if (!ieee80211_has_a4(hdr->frame_control))
return RX_DROP_MONITOR;
if (memcmp(hdr->addr4, dev_addr, ETH_ALEN) == 0)
return RX_DROP_MONITOR;
}
}
/* If there is not an established peer link and this is not a peer link
......@@ -527,7 +536,7 @@ ieee80211_rx_mesh_check(struct ieee80211_rx_data *rx)
if (ieee80211_is_data(hdr->frame_control) &&
is_multicast_ether_addr(hdr->addr1) &&
mesh_rmc_check(hdr->addr4, msh_h_get(hdr, hdrlen), rx->sdata))
mesh_rmc_check(hdr->addr3, msh_h_get(hdr, hdrlen), rx->sdata))
return RX_DROP_MONITOR;
#undef msh_h_get
......@@ -1495,7 +1504,8 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
/* illegal frame */
return RX_DROP_MONITOR;
if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6){
if (!is_multicast_ether_addr(hdr->addr1) &&
(mesh_hdr->flags & MESH_FLAGS_AE_A5_A6)) {
struct mesh_path *mppath;
rcu_read_lock();
......@@ -1512,7 +1522,9 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
rcu_read_unlock();
}
if (compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
/* Frame has reached destination. Don't forward */
if (!is_multicast_ether_addr(hdr->addr1) &&
compare_ether_addr(rx->dev->dev_addr, hdr->addr3) == 0)
return RX_CONTINUE;
mesh_hdr->ttl--;
......@@ -1532,22 +1544,21 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
rx->dev->name);
fwd_hdr = (struct ieee80211_hdr *) fwd_skb->data;
/*
* Save TA to addr1 to send TA a path error if a
* suitable next hop is not found
*/
memcpy(fwd_hdr->addr1, fwd_hdr->addr2, ETH_ALEN);
memcpy(fwd_hdr->addr2, rx->dev->dev_addr, ETH_ALEN);
info = IEEE80211_SKB_CB(fwd_skb);
memset(info, 0, sizeof(*info));
info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
info->control.vif = &rx->sdata->vif;
ieee80211_select_queue(local, fwd_skb);
if (is_multicast_ether_addr(fwd_hdr->addr3))
memcpy(fwd_hdr->addr1, fwd_hdr->addr3,
if (!is_multicast_ether_addr(fwd_hdr->addr1)) {
int err;
/*
* Save TA to addr1 to send TA a path error if a
* suitable next hop is not found
*/
memcpy(fwd_hdr->addr1, fwd_hdr->addr2,
ETH_ALEN);
else {
int err = mesh_nexthop_lookup(fwd_skb, sdata);
err = mesh_nexthop_lookup(fwd_skb, sdata);
/* Failed to immediately resolve next hop:
* fwded frame was dropped or will be added
* later to the pending skb queue. */
......@@ -1560,7 +1571,7 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
}
}
if (is_multicast_ether_addr(hdr->addr3) ||
if (is_multicast_ether_addr(hdr->addr1) ||
rx->dev->flags & IFF_PROMISC)
return RX_CONTINUE;
else
......
......@@ -1414,9 +1414,7 @@ static void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
if (ieee80211_vif_is_mesh(&sdata->vif) &&
ieee80211_is_data(hdr->frame_control)) {
if (is_multicast_ether_addr(hdr->addr3))
memcpy(hdr->addr1, hdr->addr3, ETH_ALEN);
else
if (!is_multicast_ether_addr(hdr->addr1))
if (mesh_nexthop_lookup(skb, sdata)) {
dev_put(sdata->dev);
return;
......@@ -1619,52 +1617,58 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb,
break;
#ifdef CONFIG_MAC80211_MESH
case NL80211_IFTYPE_MESH_POINT:
fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
/* Do not send frames with mesh_ttl == 0 */
sdata->u.mesh.mshstats.dropped_frames_ttl++;
ret = NETDEV_TX_OK;
goto fail;
}
memset(&mesh_hdr, 0, sizeof(mesh_hdr));
if (compare_ether_addr(dev->dev_addr,
skb->data + ETH_ALEN) == 0) {
/* RA TA DA SA */
memset(hdr.addr1, 0, ETH_ALEN);
memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
memcpy(hdr.addr3, skb->data, ETH_ALEN);
memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr, sdata);
hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
skb->data, skb->data + ETH_ALEN);
meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
sdata, NULL, NULL, NULL);
} else {
/* packet from other interface */
struct mesh_path *mppath;
int is_mesh_mcast = 1;
char *mesh_da;
memset(hdr.addr1, 0, ETH_ALEN);
memcpy(hdr.addr2, dev->dev_addr, ETH_ALEN);
memcpy(hdr.addr4, dev->dev_addr, ETH_ALEN);
rcu_read_lock();
if (is_multicast_ether_addr(skb->data))
memcpy(hdr.addr3, skb->data, ETH_ALEN);
/* DA TA mSA AE:SA */
mesh_da = skb->data;
else {
rcu_read_lock();
mppath = mpp_path_lookup(skb->data, sdata);
if (mppath)
memcpy(hdr.addr3, mppath->mpp, ETH_ALEN);
else
memset(hdr.addr3, 0xff, ETH_ALEN);
rcu_read_unlock();
if (mppath) {
/* RA TA mDA mSA AE:DA SA */
mesh_da = mppath->mpp;
is_mesh_mcast = 0;
} else
/* DA TA mSA AE:SA */
mesh_da = dev->broadcast;
}
hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
mesh_da, dev->dev_addr);
rcu_read_unlock();
if (is_mesh_mcast)
meshhdrlen =
ieee80211_new_mesh_header(&mesh_hdr,
sdata,
skb->data + ETH_ALEN,
NULL,
NULL);
else
meshhdrlen =
ieee80211_new_mesh_header(&mesh_hdr,
sdata,
NULL,
skb->data,
skb->data + ETH_ALEN);
mesh_hdr.flags |= MESH_FLAGS_AE_A5_A6;
mesh_hdr.ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &mesh_hdr.seqnum);
memcpy(mesh_hdr.eaddr1, skb->data, ETH_ALEN);
memcpy(mesh_hdr.eaddr2, skb->data + ETH_ALEN, ETH_ALEN);
sdata->u.mesh.mesh_seqnum++;
meshhdrlen = 18;
}
hdrlen = 30;
break;
#endif
case NL80211_IFTYPE_STATION:
......
......@@ -274,11 +274,11 @@ static int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr)
switch (ae) {
case 0:
return 6;
case 1:
case MESH_FLAGS_AE_A4:
return 12;
case 2:
case MESH_FLAGS_AE_A5_A6:
return 18;
case 3:
case (MESH_FLAGS_AE_A4 | MESH_FLAGS_AE_A5_A6):
return 24;
default:
return 6;
......@@ -333,10 +333,18 @@ int ieee80211_data_to_8023(struct sk_buff *skb, u8 *addr,
}
break;
case cpu_to_le16(IEEE80211_FCTL_FROMDS):
if (iftype != NL80211_IFTYPE_STATION ||
if ((iftype != NL80211_IFTYPE_STATION &&
iftype != NL80211_IFTYPE_MESH_POINT) ||
(is_multicast_ether_addr(dst) &&
!compare_ether_addr(src, addr)))
return -1;
if (iftype == NL80211_IFTYPE_MESH_POINT) {
struct ieee80211s_hdr *meshdr =
(struct ieee80211s_hdr *) (skb->data + hdrlen);
hdrlen += ieee80211_get_mesh_hdrlen(meshdr);
if (meshdr->flags & MESH_FLAGS_AE_A4)
memcpy(src, meshdr->eaddr1, ETH_ALEN);
}
break;
case cpu_to_le16(0):
if (iftype != NL80211_IFTYPE_ADHOC)
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment