diff options
Diffstat (limited to 'net/batman-adv/gateway_client.c')
-rw-r--r-- | net/batman-adv/gateway_client.c | 303 |
1 files changed, 178 insertions, 125 deletions
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index 2449afaa763..55cf2260d29 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2009-2013 B.A.T.M.A.N. contributors: +/* Copyright (C) 2009-2014 B.A.T.M.A.N. contributors: * * Marek Lindner * @@ -12,9 +12,7 @@ * General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301, USA + * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include "main.h" @@ -30,11 +28,17 @@ #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 +/* These are the offsets of the "hw type" and "hw address length" in the dhcp + * packet starting at the beginning of the dhcp header */ -#define BATADV_DHCP_OPTIONS_OFFSET 240 -#define BATADV_DHCP_REQUEST 3 +#define BATADV_DHCP_HTYPE_OFFSET 1 +#define BATADV_DHCP_HLEN_OFFSET 2 +/* Value of htype representing Ethernet */ +#define BATADV_DHCP_HTYPE_ETHERNET 0x01 +/* This is the offset of the "chaddr" field in the dhcp packet starting at the + * beginning of the dhcp header + */ +#define BATADV_DHCP_CHADDR_OFFSET 28 static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node) { @@ -105,7 +109,18 @@ static void batadv_gw_select(struct batadv_priv *bat_priv, spin_unlock_bh(&bat_priv->gw.list_lock); } -void batadv_gw_deselect(struct batadv_priv *bat_priv) +/** + * batadv_gw_reselect - force a gateway reselection + * @bat_priv: the bat priv with all the soft interface information + * + * Set a flag to remind the GW component to perform a new gateway reselection. + * However this function does not ensure that the current gateway is going to be + * deselected. The reselection mechanism may elect the same gateway once again. + * + * This means that invoking batadv_gw_reselect() does not guarantee a gateway + * change and therefore a uevent is not necessarily expected. + */ +void batadv_gw_reselect(struct batadv_priv *bat_priv) { atomic_set(&bat_priv->gw.reselect, 1); } @@ -114,6 +129,7 @@ static struct batadv_gw_node * batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv) { struct batadv_neigh_node *router; + struct batadv_neigh_ifinfo *router_ifinfo; struct batadv_gw_node *gw_node, *curr_gw = NULL; uint32_t max_gw_factor = 0, tmp_gw_factor = 0; uint32_t gw_divisor; @@ -130,14 +146,19 @@ batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv) continue; orig_node = gw_node->orig_node; - router = batadv_orig_node_get_router(orig_node); + router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT); if (!router) continue; + router_ifinfo = batadv_neigh_ifinfo_get(router, + BATADV_IF_DEFAULT); + if (!router_ifinfo) + goto next; + if (!atomic_inc_not_zero(&gw_node->refcount)) goto next; - tq_avg = router->bat_iv.tq_avg; + tq_avg = router_ifinfo->bat_iv.tq_avg; switch (atomic_read(&bat_priv->gw_sel_class)) { case 1: /* fast connection */ @@ -182,6 +203,8 @@ batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv) next: batadv_neigh_node_free_ref(router); + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); } rcu_read_unlock(); @@ -207,6 +230,11 @@ void batadv_gw_check_client_stop(struct batadv_priv *bat_priv) if (!curr_gw) return; + /* deselect the current gateway so that next time that client mode is + * enabled a proper GW_ADD event can be sent + */ + batadv_gw_select(bat_priv, NULL); + /* if batman-adv is switching the gw client mode off and a gateway was * already selected, send a DEL uevent */ @@ -219,6 +247,7 @@ void batadv_gw_election(struct batadv_priv *bat_priv) { struct batadv_gw_node *curr_gw = NULL, *next_gw = NULL; struct batadv_neigh_node *router = NULL; + struct batadv_neigh_ifinfo *router_ifinfo = NULL; char gw_addr[18] = { '\0' }; if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT) @@ -237,9 +266,17 @@ void batadv_gw_election(struct batadv_priv *bat_priv) if (next_gw) { sprintf(gw_addr, "%pM", next_gw->orig_node->orig); - router = batadv_orig_node_get_router(next_gw->orig_node); + router = batadv_orig_router_get(next_gw->orig_node, + BATADV_IF_DEFAULT); if (!router) { - batadv_gw_deselect(bat_priv); + batadv_gw_reselect(bat_priv); + goto out; + } + + router_ifinfo = batadv_neigh_ifinfo_get(router, + BATADV_IF_DEFAULT); + if (!router_ifinfo) { + batadv_gw_reselect(bat_priv); goto out; } } @@ -256,7 +293,8 @@ void batadv_gw_election(struct batadv_priv *bat_priv) next_gw->bandwidth_down / 10, next_gw->bandwidth_down % 10, next_gw->bandwidth_up / 10, - next_gw->bandwidth_up % 10, router->bat_iv.tq_avg); + next_gw->bandwidth_up % 10, + router_ifinfo->bat_iv.tq_avg); batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD, gw_addr); } else { @@ -266,7 +304,8 @@ void batadv_gw_election(struct batadv_priv *bat_priv) next_gw->bandwidth_down / 10, next_gw->bandwidth_down % 10, next_gw->bandwidth_up / 10, - next_gw->bandwidth_up % 10, router->bat_iv.tq_avg); + next_gw->bandwidth_up % 10, + router_ifinfo->bat_iv.tq_avg); batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE, gw_addr); } @@ -280,33 +319,47 @@ out: batadv_gw_node_free_ref(next_gw); if (router) batadv_neigh_node_free_ref(router); + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); } void batadv_gw_check_election(struct batadv_priv *bat_priv, struct batadv_orig_node *orig_node) { + struct batadv_neigh_ifinfo *router_orig_tq = NULL; + struct batadv_neigh_ifinfo *router_gw_tq = NULL; struct batadv_orig_node *curr_gw_orig; struct batadv_neigh_node *router_gw = NULL, *router_orig = NULL; uint8_t gw_tq_avg, orig_tq_avg; curr_gw_orig = batadv_gw_get_selected_orig(bat_priv); if (!curr_gw_orig) - goto deselect; + goto reselect; - router_gw = batadv_orig_node_get_router(curr_gw_orig); + router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT); if (!router_gw) - goto deselect; + goto reselect; + + router_gw_tq = batadv_neigh_ifinfo_get(router_gw, + BATADV_IF_DEFAULT); + if (!router_gw_tq) + goto reselect; /* this node already is the gateway */ if (curr_gw_orig == orig_node) goto out; - router_orig = batadv_orig_node_get_router(orig_node); + router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT); if (!router_orig) goto out; - gw_tq_avg = router_gw->bat_iv.tq_avg; - orig_tq_avg = router_orig->bat_iv.tq_avg; + router_orig_tq = batadv_neigh_ifinfo_get(router_orig, + BATADV_IF_DEFAULT); + if (!router_orig_tq) + goto out; + + gw_tq_avg = router_gw_tq->bat_iv.tq_avg; + orig_tq_avg = router_orig_tq->bat_iv.tq_avg; /* the TQ value has to be better */ if (orig_tq_avg < gw_tq_avg) @@ -323,8 +376,8 @@ void batadv_gw_check_election(struct batadv_priv *bat_priv, "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n", gw_tq_avg, orig_tq_avg); -deselect: - batadv_gw_deselect(bat_priv); +reselect: + batadv_gw_reselect(bat_priv); out: if (curr_gw_orig) batadv_orig_node_free_ref(curr_gw_orig); @@ -332,6 +385,10 @@ out: batadv_neigh_node_free_ref(router_gw); if (router_orig) batadv_neigh_node_free_ref(router_orig); + if (router_gw_tq) + batadv_neigh_ifinfo_free_ref(router_gw_tq); + if (router_orig_tq) + batadv_neigh_ifinfo_free_ref(router_orig_tq); return; } @@ -454,7 +511,7 @@ void batadv_gw_node_update(struct batadv_priv *bat_priv, */ curr_gw = batadv_gw_get_selected_gw_node(bat_priv); if (gw_node == curr_gw) - batadv_gw_deselect(bat_priv); + batadv_gw_reselect(bat_priv); } out: @@ -480,7 +537,7 @@ void batadv_gw_node_purge(struct batadv_priv *bat_priv) struct batadv_gw_node *gw_node, *curr_gw; struct hlist_node *node_tmp; unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT); - int do_deselect = 0; + int do_reselect = 0; curr_gw = batadv_gw_get_selected_gw_node(bat_priv); @@ -494,7 +551,7 @@ void batadv_gw_node_purge(struct batadv_priv *bat_priv) continue; if (curr_gw == gw_node) - do_deselect = 1; + do_reselect = 1; hlist_del_rcu(&gw_node->list); batadv_gw_node_free_ref(gw_node); @@ -502,9 +559,9 @@ void batadv_gw_node_purge(struct batadv_priv *bat_priv) spin_unlock_bh(&bat_priv->gw.list_lock); - /* gw_deselect() needs to acquire the gw_list_lock */ - if (do_deselect) - batadv_gw_deselect(bat_priv); + /* gw_reselect() needs to acquire the gw_list_lock */ + if (do_reselect) + batadv_gw_reselect(bat_priv); if (curr_gw) batadv_gw_node_free_ref(curr_gw); @@ -517,28 +574,36 @@ static int batadv_write_buffer_text(struct batadv_priv *bat_priv, { struct batadv_gw_node *curr_gw; struct batadv_neigh_node *router; + struct batadv_neigh_ifinfo *router_ifinfo = NULL; int ret = -1; - router = batadv_orig_node_get_router(gw_node->orig_node); + router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT); if (!router) goto out; + router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT); + if (!router_ifinfo) + goto out; + curr_gw = batadv_gw_get_selected_gw_node(bat_priv); ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n", (curr_gw == gw_node ? "=>" : " "), gw_node->orig_node->orig, - router->bat_iv.tq_avg, router->addr, + router_ifinfo->bat_iv.tq_avg, router->addr, router->if_incoming->net_dev->name, gw_node->bandwidth_down / 10, gw_node->bandwidth_down % 10, gw_node->bandwidth_up / 10, gw_node->bandwidth_up % 10); - batadv_neigh_node_free_ref(router); if (curr_gw) batadv_gw_node_free_ref(curr_gw); out: + if (router_ifinfo) + batadv_neigh_ifinfo_free_ref(router_ifinfo); + if (router) + batadv_neigh_node_free_ref(router); return ret; } @@ -582,80 +647,39 @@ out: return 0; } -/* this call might reallocate skb data */ -static bool batadv_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 + BATADV_DHCP_OPTIONS_OFFSET + 1) - goto out; - - p = skb->data + header_len + BATADV_DHCP_OPTIONS_OFFSET; - pkt_len -= header_len + BATADV_DHCP_OPTIONS_OFFSET + 1; - - /* Access the dhcp option lists. Each entry is made up by: - * - octet 1: option type - * - octet 2: option data len (only if type != 255 and 0) - * - octet 3: option data - */ - while (*p != 255 && !ret) { - /* p now points to the first octet: option type */ - if (*p == 53) { - /* type 53 is the message type option. - * Jump the len octet and go to the data octet - */ - if (pkt_len < 2) - goto out; - p += 2; - - /* check if the message type is what we need */ - if (*p == BATADV_DHCP_REQUEST) - ret = true; - break; - } else if (*p == 0) { - /* option type 0 (padding), just go forward */ - if (pkt_len < 1) - goto out; - pkt_len--; - p++; - } else { - /* This is any other option. So we get the length... */ - if (pkt_len < 1) - goto out; - pkt_len--; - p++; - - /* ...and then we jump over the data */ - if (pkt_len < 1 + (*p)) - goto out; - pkt_len -= 1 + (*p); - p += 1 + (*p); - } - } -out: - return ret; -} - -/* this call might reallocate skb data */ -bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) +/** + * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message + * @skb: the packet to check + * @header_len: a pointer to the batman-adv header size + * @chaddr: buffer where the client address will be stored. Valid + * only if the function returns BATADV_DHCP_TO_CLIENT + * + * Returns: + * - BATADV_DHCP_NO if the packet is not a dhcp message or if there was an error + * while parsing it + * - BATADV_DHCP_TO_SERVER if this is a message going to the DHCP server + * - BATADV_DHCP_TO_CLIENT if this is a message going to a DHCP client + * + * This function may re-allocate the data buffer of the skb passed as argument. + */ +enum batadv_dhcp_recipient +batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len, + uint8_t *chaddr) { + enum batadv_dhcp_recipient ret = BATADV_DHCP_NO; struct ethhdr *ethhdr; struct iphdr *iphdr; struct ipv6hdr *ipv6hdr; struct udphdr *udphdr; struct vlan_ethhdr *vhdr; + int chaddr_offset; __be16 proto; + uint8_t *p; /* check for ethernet header */ if (!pskb_may_pull(skb, *header_len + ETH_HLEN)) - return false; + return BATADV_DHCP_NO; + ethhdr = (struct ethhdr *)skb->data; proto = ethhdr->h_proto; *header_len += ETH_HLEN; @@ -663,7 +687,7 @@ bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) /* check for initial vlan header */ if (proto == htons(ETH_P_8021Q)) { if (!pskb_may_pull(skb, *header_len + VLAN_HLEN)) - return false; + return BATADV_DHCP_NO; vhdr = (struct vlan_ethhdr *)skb->data; proto = vhdr->h_vlan_encapsulated_proto; @@ -674,32 +698,34 @@ bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) switch (proto) { case htons(ETH_P_IP): if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr))) - return false; + return BATADV_DHCP_NO; + iphdr = (struct iphdr *)(skb->data + *header_len); *header_len += iphdr->ihl * 4; /* check for udp header */ if (iphdr->protocol != IPPROTO_UDP) - return false; + return BATADV_DHCP_NO; break; case htons(ETH_P_IPV6): if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr))) - return false; + return BATADV_DHCP_NO; + ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len); *header_len += sizeof(*ipv6hdr); /* check for udp header */ if (ipv6hdr->nexthdr != IPPROTO_UDP) - return false; + return BATADV_DHCP_NO; break; default: - return false; + return BATADV_DHCP_NO; } if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr))) - return false; + return BATADV_DHCP_NO; /* skb->data might have been reallocated by pskb_may_pull() */ ethhdr = (struct ethhdr *)skb->data; @@ -710,17 +736,40 @@ bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) *header_len += sizeof(*udphdr); /* check for bootp port */ - if ((proto == htons(ETH_P_IP)) && - (udphdr->dest != htons(67))) - return false; + switch (proto) { + case htons(ETH_P_IP): + if (udphdr->dest == htons(67)) + ret = BATADV_DHCP_TO_SERVER; + else if (udphdr->source == htons(67)) + ret = BATADV_DHCP_TO_CLIENT; + break; + case htons(ETH_P_IPV6): + if (udphdr->dest == htons(547)) + ret = BATADV_DHCP_TO_SERVER; + else if (udphdr->source == htons(547)) + ret = BATADV_DHCP_TO_CLIENT; + break; + } - if ((proto == htons(ETH_P_IPV6)) && - (udphdr->dest != htons(547))) - return false; + chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET; + /* store the client address if the message is going to a client */ + if (ret == BATADV_DHCP_TO_CLIENT && + pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) { + /* check if the DHCP packet carries an Ethernet DHCP */ + p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET; + if (*p != BATADV_DHCP_HTYPE_ETHERNET) + return BATADV_DHCP_NO; + + /* check if the DHCP packet carries a valid Ethernet address */ + p = skb->data + *header_len + BATADV_DHCP_HLEN_OFFSET; + if (*p != ETH_ALEN) + return BATADV_DHCP_NO; + + memcpy(chaddr, skb->data + chaddr_offset, ETH_ALEN); + } - return true; + return ret; } - /** * batadv_gw_out_of_range - check if the dhcp request destination is the best gw * @bat_priv: the bat priv with all the soft interface information @@ -734,6 +783,7 @@ bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len) * false otherwise. * * This call might reallocate skb data. + * Must be invoked only when the DHCP packet is going TO a DHCP SERVER. */ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct sk_buff *skb) @@ -741,19 +791,14 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL; struct batadv_orig_node *orig_dst_node = NULL; struct batadv_gw_node *gw_node = NULL, *curr_gw = NULL; - struct ethhdr *ethhdr; - bool ret, out_of_range = false; - unsigned int header_len = 0; + struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo; + struct ethhdr *ethhdr = (struct ethhdr *)skb->data; + bool out_of_range = false; uint8_t curr_tq_avg; unsigned short vid; vid = batadv_get_vid(skb, 0); - ret = batadv_gw_is_dhcp_target(skb, &header_len); - if (!ret) - goto out; - - ethhdr = (struct ethhdr *)skb->data; orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source, ethhdr->h_dest, vid); if (!orig_dst_node) @@ -763,10 +808,6 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, if (!gw_node->bandwidth_down == 0) goto out; - ret = batadv_is_type_dhcprequest(skb, header_len); - if (!ret) - goto out; - switch (atomic_read(&bat_priv->gw_mode)) { case BATADV_GW_MODE_SERVER: /* If we are a GW then we are our best GW. We can artificially @@ -792,7 +833,14 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, if (!neigh_curr) goto out; - curr_tq_avg = neigh_curr->bat_iv.tq_avg; + curr_ifinfo = batadv_neigh_ifinfo_get(neigh_curr, + BATADV_IF_DEFAULT); + if (!curr_ifinfo) + goto out; + + curr_tq_avg = curr_ifinfo->bat_iv.tq_avg; + batadv_neigh_ifinfo_free_ref(curr_ifinfo); + break; case BATADV_GW_MODE_OFF: default: @@ -803,8 +851,13 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, if (!neigh_old) goto out; - if (curr_tq_avg - neigh_old->bat_iv.tq_avg > BATADV_GW_THRESHOLD) + old_ifinfo = batadv_neigh_ifinfo_get(neigh_old, BATADV_IF_DEFAULT); + if (!old_ifinfo) + goto out; + + if ((curr_tq_avg - old_ifinfo->bat_iv.tq_avg) > BATADV_GW_THRESHOLD) out_of_range = true; + batadv_neigh_ifinfo_free_ref(old_ifinfo); out: if (orig_dst_node) |