#include <net/sock.h>
#include <net/tcp_states.h>
#include <linux/llc.h>
+#include <linux/slab.h>
+
+static int llc_mac_header_len(unsigned short devtype)
+{
+ switch (devtype) {
+ case ARPHRD_ETHER:
+ case ARPHRD_LOOPBACK:
+ return sizeof(struct ethhdr);
+#if defined(CONFIG_TR) || defined(CONFIG_TR_MODULE)
+ case ARPHRD_IEEE802_TR:
+ return sizeof(struct trh_hdr);
+#endif
+ }
+ return 0;
+}
/**
* llc_alloc_frame - allocates sk_buff for frame
* @dev: network device this skb will be sent over
+ * @type: pdu type to allocate
+ * @data_size: data size to allocate
*
* Allocates an sk_buff for frame and initializes sk_buff fields.
* Returns allocated skb or %NULL when out of memory.
*/
-struct sk_buff *llc_alloc_frame(struct sock *sk, struct net_device *dev)
+struct sk_buff *llc_alloc_frame(struct sock *sk, struct net_device *dev,
+ u8 type, u32 data_size)
{
- struct sk_buff *skb = alloc_skb(128, GFP_ATOMIC);
+ int hlen = type == LLC_PDU_TYPE_U ? 3 : 4;
+ struct sk_buff *skb;
+
+ hlen += llc_mac_header_len(dev->type);
+ skb = alloc_skb(hlen + data_size, GFP_ATOMIC);
if (skb) {
- skb_reserve(skb, 50);
- skb->nh.raw = skb->h.raw = skb->data;
+ skb_reset_mac_header(skb);
+ skb_reserve(skb, hlen);
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
skb->protocol = htons(ETH_P_802_2);
skb->dev = dev;
- skb->mac.raw = skb->head;
if (sk != NULL)
skb_set_owner_w(skb, sk);
}
{
struct sockaddr_llc *addr;
- if (skb->sk->sk_type == SOCK_STREAM) /* See UNIX98 */
- return;
/* save primitive for use by the user. */
addr = llc_ui_skb_cb(skb);
+
+ memset(addr, 0, sizeof(*addr));
addr->sllc_family = sk->sk_family;
addr->sllc_arphrd = skb->dev->type;
addr->sllc_test = prim == LLC_TEST_PRIM;
if (sock_queue_rcv_skb(skb->sk, skb))
kfree_skb(skb);
}
- }
+ }
kfree_skb(skb);
}
* This function is called when upper layer wants to send a TEST pdu.
* Returns 0 for success, 1 otherwise.
*/
-void llc_build_and_send_test_pkt(struct llc_sap *sap,
+void llc_build_and_send_test_pkt(struct llc_sap *sap,
struct sk_buff *skb, u8 *dmac, u8 dsap)
{
struct llc_sap_state_ev *ev = llc_sap_ev(skb);
ev->daddr.lsap = dsap;
memcpy(ev->saddr.mac, skb->dev->dev_addr, IFHWADDRLEN);
memcpy(ev->daddr.mac, dmac, IFHWADDRLEN);
-
+
ev->type = LLC_SAP_EV_TYPE_PRIM;
ev->prim = LLC_TEST_PRIM;
ev->prim_type = LLC_PRIM_TYPE_REQ;
*
* Sends received pdus to the sap state machine.
*/
-static void llc_sap_rcv(struct llc_sap *sap, struct sk_buff *skb)
+static void llc_sap_rcv(struct llc_sap *sap, struct sk_buff *skb,
+ struct sock *sk)
{
struct llc_sap_state_ev *ev = llc_sap_ev(skb);
ev->type = LLC_SAP_EV_TYPE_PDU;
ev->reason = 0;
+ skb->sk = sk;
llc_sap_state_process(sap, skb);
}
+static inline bool llc_dgram_match(const struct llc_sap *sap,
+ const struct llc_addr *laddr,
+ const struct sock *sk)
+{
+ struct llc_sock *llc = llc_sk(sk);
+
+ return sk->sk_type == SOCK_DGRAM &&
+ llc->laddr.lsap == laddr->lsap &&
+ llc_mac_match(llc->laddr.mac, laddr->mac);
+}
+
/**
* llc_lookup_dgram - Finds dgram socket for the local sap/mac
* @sap: SAP
* mac, and local sap. Returns pointer for socket found, %NULL otherwise.
*/
static struct sock *llc_lookup_dgram(struct llc_sap *sap,
- struct llc_addr *laddr)
+ const struct llc_addr *laddr)
{
struct sock *rc;
- struct hlist_node *node;
-
- read_lock_bh(&sap->sk_list.lock);
- sk_for_each(rc, node, &sap->sk_list.list) {
- struct llc_sock *llc = llc_sk(rc);
+ struct hlist_nulls_node *node;
+ int slot = llc_sk_laddr_hashfn(sap, laddr);
+ struct hlist_nulls_head *laddr_hb = &sap->sk_laddr_hash[slot];
- if (rc->sk_type == SOCK_DGRAM &&
- llc->laddr.lsap == laddr->lsap &&
- llc_mac_match(llc->laddr.mac, laddr->mac)) {
- sock_hold(rc);
+ rcu_read_lock_bh();
+again:
+ sk_nulls_for_each_rcu(rc, node, laddr_hb) {
+ if (llc_dgram_match(sap, laddr, rc)) {
+ /* Extra checks required by SLAB_DESTROY_BY_RCU */
+ if (unlikely(!atomic_inc_not_zero(&rc->sk_refcnt)))
+ goto again;
+ if (unlikely(llc_sk(rc)->sap != sap ||
+ !llc_dgram_match(sap, laddr, rc))) {
+ sock_put(rc);
+ continue;
+ }
goto found;
}
}
rc = NULL;
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (unlikely(get_nulls_value(node) != slot))
+ goto again;
found:
- read_unlock_bh(&sap->sk_list.lock);
+ rcu_read_unlock_bh();
return rc;
}
+static inline bool llc_mcast_match(const struct llc_sap *sap,
+ const struct llc_addr *laddr,
+ const struct sk_buff *skb,
+ const struct sock *sk)
+{
+ struct llc_sock *llc = llc_sk(sk);
+
+ return sk->sk_type == SOCK_DGRAM &&
+ llc->laddr.lsap == laddr->lsap &&
+ llc->dev == skb->dev;
+}
+
+static void llc_do_mcast(struct llc_sap *sap, struct sk_buff *skb,
+ struct sock **stack, int count)
+{
+ struct sk_buff *skb1;
+ int i;
+
+ for (i = 0; i < count; i++) {
+ skb1 = skb_clone(skb, GFP_ATOMIC);
+ if (!skb1) {
+ sock_put(stack[i]);
+ continue;
+ }
+
+ llc_sap_rcv(sap, skb1, stack[i]);
+ sock_put(stack[i]);
+ }
+}
+
+/**
+ * llc_sap_mcast - Deliver multicast PDU's to all matching datagram sockets.
+ * @sap: SAP
+ * @laddr: address of local LLC (MAC + SAP)
+ *
+ * Search socket list of the SAP and finds connections with same sap.
+ * Deliver clone to each.
+ */
+static void llc_sap_mcast(struct llc_sap *sap,
+ const struct llc_addr *laddr,
+ struct sk_buff *skb)
+{
+ int i = 0, count = 256 / sizeof(struct sock *);
+ struct sock *sk, *stack[count];
+ struct hlist_node *node;
+ struct llc_sock *llc;
+ struct hlist_head *dev_hb = llc_sk_dev_hash(sap, skb->dev->ifindex);
+
+ spin_lock_bh(&sap->sk_lock);
+ hlist_for_each_entry(llc, node, dev_hb, dev_hash_node) {
+
+ sk = &llc->sk;
+
+ if (!llc_mcast_match(sap, laddr, skb, sk))
+ continue;
+
+ sock_hold(sk);
+ if (i < count)
+ stack[i++] = sk;
+ else {
+ llc_do_mcast(sap, skb, stack, i);
+ i = 0;
+ }
+ }
+ spin_unlock_bh(&sap->sk_lock);
+
+ llc_do_mcast(sap, skb, stack, i);
+}
+
+
void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb)
{
struct llc_addr laddr;
- struct sock *sk;
llc_pdu_decode_da(skb, laddr.mac);
llc_pdu_decode_dsap(skb, &laddr.lsap);
- sk = llc_lookup_dgram(sap, &laddr);
- if (sk) {
- skb_set_owner_r(skb, sk);
- llc_sap_rcv(sap, skb);
- sock_put(sk);
- } else
+ if (llc_mac_multicast(laddr.mac)) {
+ llc_sap_mcast(sap, &laddr, skb);
kfree_skb(skb);
+ } else {
+ struct sock *sk = llc_lookup_dgram(sap, &laddr);
+ if (sk) {
+ llc_sap_rcv(sap, skb, sk);
+ sock_put(sk);
+ } else
+ kfree_skb(skb);
+ }
}