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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /net/llc/af_llc.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/llc/af_llc.c')
-rw-r--r--net/llc/af_llc.c1308
1 files changed, 1308 insertions, 0 deletions
diff --git a/net/llc/af_llc.c b/net/llc/af_llc.c
new file mode 100644
index 0000000000..20551cfb7d
--- /dev/null
+++ b/net/llc/af_llc.c
@@ -0,0 +1,1308 @@
+/*
+ * af_llc.c - LLC User Interface SAPs
+ * Description:
+ * Functions in this module are implementation of socket based llc
+ * communications for the Linux operating system. Support of llc class
+ * one and class two is provided via SOCK_DGRAM and SOCK_STREAM
+ * respectively.
+ *
+ * An llc2 connection is (mac + sap), only one llc2 sap connection
+ * is allowed per mac. Though one sap may have multiple mac + sap
+ * connections.
+ *
+ * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
+ * 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * This program can be redistributed or modified under the terms of the
+ * GNU General Public License as published by the Free Software Foundation.
+ * This program is distributed without any warranty or implied warranty
+ * of merchantability or fitness for a particular purpose.
+ *
+ * See the GNU General Public License for more details.
+ */
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/sched/signal.h>
+
+#include <net/llc.h>
+#include <net/llc_sap.h>
+#include <net/llc_pdu.h>
+#include <net/llc_conn.h>
+#include <net/tcp_states.h>
+
+/* remember: uninitialized global data is zeroed because its in .bss */
+static u16 llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
+static u16 llc_ui_sap_link_no_max[256];
+static struct sockaddr_llc llc_ui_addrnull;
+static const struct proto_ops llc_ui_ops;
+
+static bool llc_ui_wait_for_conn(struct sock *sk, long timeout);
+static int llc_ui_wait_for_disc(struct sock *sk, long timeout);
+static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout);
+
+#if 0
+#define dprintk(args...) printk(KERN_DEBUG args)
+#else
+#define dprintk(args...) do {} while (0)
+#endif
+
+/* Maybe we'll add some more in the future. */
+#define LLC_CMSG_PKTINFO 1
+
+
+/**
+ * llc_ui_next_link_no - return the next unused link number for a sap
+ * @sap: Address of sap to get link number from.
+ *
+ * Return the next unused link number for a given sap.
+ */
+static inline u16 llc_ui_next_link_no(int sap)
+{
+ return llc_ui_sap_link_no_max[sap]++;
+}
+
+/**
+ * llc_proto_type - return eth protocol for ARP header type
+ * @arphrd: ARP header type.
+ *
+ * Given an ARP header type return the corresponding ethernet protocol.
+ */
+static inline __be16 llc_proto_type(u16 arphrd)
+{
+ return htons(ETH_P_802_2);
+}
+
+/**
+ * llc_ui_addr_null - determines if a address structure is null
+ * @addr: Address to test if null.
+ */
+static inline u8 llc_ui_addr_null(struct sockaddr_llc *addr)
+{
+ return !memcmp(addr, &llc_ui_addrnull, sizeof(*addr));
+}
+
+/**
+ * llc_ui_header_len - return length of llc header based on operation
+ * @sk: Socket which contains a valid llc socket type.
+ * @addr: Complete sockaddr_llc structure received from the user.
+ *
+ * Provide the length of the llc header depending on what kind of
+ * operation the user would like to perform and the type of socket.
+ * Returns the correct llc header length.
+ */
+static inline u8 llc_ui_header_len(struct sock *sk, struct sockaddr_llc *addr)
+{
+ u8 rc = LLC_PDU_LEN_U;
+
+ if (addr->sllc_test)
+ rc = LLC_PDU_LEN_U;
+ else if (addr->sllc_xid)
+ /* We need to expand header to sizeof(struct llc_xid_info)
+ * since llc_pdu_init_as_xid_cmd() sets 4,5,6 bytes of LLC header
+ * as XID PDU. In llc_ui_sendmsg() we reserved header size and then
+ * filled all other space with user data. If we won't reserve this
+ * bytes, llc_pdu_init_as_xid_cmd() will overwrite user data
+ */
+ rc = LLC_PDU_LEN_U_XID;
+ else if (sk->sk_type == SOCK_STREAM)
+ rc = LLC_PDU_LEN_I;
+ return rc;
+}
+
+/**
+ * llc_ui_send_data - send data via reliable llc2 connection
+ * @sk: Connection the socket is using.
+ * @skb: Data the user wishes to send.
+ * @noblock: can we block waiting for data?
+ *
+ * Send data via reliable llc2 connection.
+ * Returns 0 upon success, non-zero if action did not succeed.
+ *
+ * This function always consumes a reference to the skb.
+ */
+static int llc_ui_send_data(struct sock* sk, struct sk_buff *skb, int noblock)
+{
+ struct llc_sock* llc = llc_sk(sk);
+
+ if (unlikely(llc_data_accept_state(llc->state) ||
+ llc->remote_busy_flag ||
+ llc->p_flag)) {
+ long timeout = sock_sndtimeo(sk, noblock);
+ int rc;
+
+ rc = llc_ui_wait_for_busy_core(sk, timeout);
+ if (rc) {
+ kfree_skb(skb);
+ return rc;
+ }
+ }
+ return llc_build_and_send_pkt(sk, skb);
+}
+
+static void llc_ui_sk_init(struct socket *sock, struct sock *sk)
+{
+ sock_graft(sk, sock);
+ sk->sk_type = sock->type;
+ sock->ops = &llc_ui_ops;
+}
+
+static struct proto llc_proto = {
+ .name = "LLC",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct llc_sock),
+ .slab_flags = SLAB_TYPESAFE_BY_RCU,
+};
+
+/**
+ * llc_ui_create - alloc and init a new llc_ui socket
+ * @net: network namespace (must be default network)
+ * @sock: Socket to initialize and attach allocated sk to.
+ * @protocol: Unused.
+ * @kern: on behalf of kernel or userspace
+ *
+ * Allocate and initialize a new llc_ui socket, validate the user wants a
+ * socket type we have available.
+ * Returns 0 upon success, negative upon failure.
+ */
+static int llc_ui_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk;
+ int rc = -ESOCKTNOSUPPORT;
+
+ if (!ns_capable(net->user_ns, CAP_NET_RAW))
+ return -EPERM;
+
+ if (!net_eq(net, &init_net))
+ return -EAFNOSUPPORT;
+
+ if (likely(sock->type == SOCK_DGRAM || sock->type == SOCK_STREAM)) {
+ rc = -ENOMEM;
+ sk = llc_sk_alloc(net, PF_LLC, GFP_KERNEL, &llc_proto, kern);
+ if (sk) {
+ rc = 0;
+ llc_ui_sk_init(sock, sk);
+ }
+ }
+ return rc;
+}
+
+/**
+ * llc_ui_release - shutdown socket
+ * @sock: Socket to release.
+ *
+ * Shutdown and deallocate an existing socket.
+ */
+static int llc_ui_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc;
+
+ if (unlikely(sk == NULL))
+ goto out;
+ sock_hold(sk);
+ lock_sock(sk);
+ llc = llc_sk(sk);
+ dprintk("%s: closing local(%02X) remote(%02X)\n", __func__,
+ llc->laddr.lsap, llc->daddr.lsap);
+ if (!llc_send_disc(sk))
+ llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
+ if (!sock_flag(sk, SOCK_ZAPPED)) {
+ struct llc_sap *sap = llc->sap;
+
+ /* Hold this for release_sock(), so that llc_backlog_rcv()
+ * could still use it.
+ */
+ llc_sap_hold(sap);
+ llc_sap_remove_socket(llc->sap, sk);
+ release_sock(sk);
+ llc_sap_put(sap);
+ } else {
+ release_sock(sk);
+ }
+ netdev_put(llc->dev, &llc->dev_tracker);
+ sock_put(sk);
+ llc_sk_free(sk);
+out:
+ return 0;
+}
+
+/**
+ * llc_ui_autoport - provide dynamically allocate SAP number
+ *
+ * Provide the caller with a dynamically allocated SAP number according
+ * to the rules that are set in this function. Returns: 0, upon failure,
+ * SAP number otherwise.
+ */
+static int llc_ui_autoport(void)
+{
+ struct llc_sap *sap;
+ int i, tries = 0;
+
+ while (tries < LLC_SAP_DYN_TRIES) {
+ for (i = llc_ui_sap_last_autoport;
+ i < LLC_SAP_DYN_STOP; i += 2) {
+ sap = llc_sap_find(i);
+ if (!sap) {
+ llc_ui_sap_last_autoport = i + 2;
+ goto out;
+ }
+ llc_sap_put(sap);
+ }
+ llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
+ tries++;
+ }
+ i = 0;
+out:
+ return i;
+}
+
+/**
+ * llc_ui_autobind - automatically bind a socket to a sap
+ * @sock: socket to bind
+ * @addr: address to connect to
+ *
+ * Used by llc_ui_connect and llc_ui_sendmsg when the user hasn't
+ * specifically used llc_ui_bind to bind to an specific address/sap
+ *
+ * Returns: 0 upon success, negative otherwise.
+ */
+static int llc_ui_autobind(struct socket *sock, struct sockaddr_llc *addr)
+{
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ struct net_device *dev = NULL;
+ struct llc_sap *sap;
+ int rc = -EINVAL;
+
+ if (!sock_flag(sk, SOCK_ZAPPED))
+ goto out;
+ if (!addr->sllc_arphrd)
+ addr->sllc_arphrd = ARPHRD_ETHER;
+ if (addr->sllc_arphrd != ARPHRD_ETHER)
+ goto out;
+ rc = -ENODEV;
+ if (sk->sk_bound_dev_if) {
+ dev = dev_get_by_index(&init_net, sk->sk_bound_dev_if);
+ if (dev && addr->sllc_arphrd != dev->type) {
+ dev_put(dev);
+ dev = NULL;
+ }
+ } else
+ dev = dev_getfirstbyhwtype(&init_net, addr->sllc_arphrd);
+ if (!dev)
+ goto out;
+ rc = -EUSERS;
+ llc->laddr.lsap = llc_ui_autoport();
+ if (!llc->laddr.lsap)
+ goto out;
+ rc = -EBUSY; /* some other network layer is using the sap */
+ sap = llc_sap_open(llc->laddr.lsap, NULL);
+ if (!sap)
+ goto out;
+
+ /* Note: We do not expect errors from this point. */
+ llc->dev = dev;
+ netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
+ dev = NULL;
+
+ memcpy(llc->laddr.mac, llc->dev->dev_addr, IFHWADDRLEN);
+ memcpy(&llc->addr, addr, sizeof(llc->addr));
+ /* assign new connection to its SAP */
+ llc_sap_add_socket(sap, sk);
+ sock_reset_flag(sk, SOCK_ZAPPED);
+ rc = 0;
+out:
+ dev_put(dev);
+ return rc;
+}
+
+/**
+ * llc_ui_bind - bind a socket to a specific address.
+ * @sock: Socket to bind an address to.
+ * @uaddr: Address the user wants the socket bound to.
+ * @addrlen: Length of the uaddr structure.
+ *
+ * Bind a socket to a specific address. For llc a user is able to bind to
+ * a specific sap only or mac + sap.
+ * If the user desires to bind to a specific mac + sap, it is possible to
+ * have multiple sap connections via multiple macs.
+ * Bind and autobind for that matter must enforce the correct sap usage
+ * otherwise all hell will break loose.
+ * Returns: 0 upon success, negative otherwise.
+ */
+static int llc_ui_bind(struct socket *sock, struct sockaddr *uaddr, int addrlen)
+{
+ struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ struct net_device *dev = NULL;
+ struct llc_sap *sap;
+ int rc = -EINVAL;
+
+ lock_sock(sk);
+ if (unlikely(!sock_flag(sk, SOCK_ZAPPED) || addrlen != sizeof(*addr)))
+ goto out;
+ rc = -EAFNOSUPPORT;
+ if (!addr->sllc_arphrd)
+ addr->sllc_arphrd = ARPHRD_ETHER;
+ if (unlikely(addr->sllc_family != AF_LLC || addr->sllc_arphrd != ARPHRD_ETHER))
+ goto out;
+ dprintk("%s: binding %02X\n", __func__, addr->sllc_sap);
+ rc = -ENODEV;
+ rcu_read_lock();
+ if (sk->sk_bound_dev_if) {
+ dev = dev_get_by_index_rcu(&init_net, sk->sk_bound_dev_if);
+ if (dev) {
+ if (is_zero_ether_addr(addr->sllc_mac))
+ memcpy(addr->sllc_mac, dev->dev_addr,
+ IFHWADDRLEN);
+ if (addr->sllc_arphrd != dev->type ||
+ !ether_addr_equal(addr->sllc_mac,
+ dev->dev_addr)) {
+ rc = -EINVAL;
+ dev = NULL;
+ }
+ }
+ } else {
+ dev = dev_getbyhwaddr_rcu(&init_net, addr->sllc_arphrd,
+ addr->sllc_mac);
+ }
+ dev_hold(dev);
+ rcu_read_unlock();
+ if (!dev)
+ goto out;
+
+ if (!addr->sllc_sap) {
+ rc = -EUSERS;
+ addr->sllc_sap = llc_ui_autoport();
+ if (!addr->sllc_sap)
+ goto out;
+ }
+ sap = llc_sap_find(addr->sllc_sap);
+ if (!sap) {
+ sap = llc_sap_open(addr->sllc_sap, NULL);
+ rc = -EBUSY; /* some other network layer is using the sap */
+ if (!sap)
+ goto out;
+ } else {
+ struct llc_addr laddr, daddr;
+ struct sock *ask;
+
+ memset(&laddr, 0, sizeof(laddr));
+ memset(&daddr, 0, sizeof(daddr));
+ /*
+ * FIXME: check if the address is multicast,
+ * only SOCK_DGRAM can do this.
+ */
+ memcpy(laddr.mac, addr->sllc_mac, IFHWADDRLEN);
+ laddr.lsap = addr->sllc_sap;
+ rc = -EADDRINUSE; /* mac + sap clash. */
+ ask = llc_lookup_established(sap, &daddr, &laddr, &init_net);
+ if (ask) {
+ sock_put(ask);
+ goto out_put;
+ }
+ }
+
+ /* Note: We do not expect errors from this point. */
+ llc->dev = dev;
+ netdev_tracker_alloc(llc->dev, &llc->dev_tracker, GFP_KERNEL);
+ dev = NULL;
+
+ llc->laddr.lsap = addr->sllc_sap;
+ memcpy(llc->laddr.mac, addr->sllc_mac, IFHWADDRLEN);
+ memcpy(&llc->addr, addr, sizeof(llc->addr));
+ /* assign new connection to its SAP */
+ llc_sap_add_socket(sap, sk);
+ sock_reset_flag(sk, SOCK_ZAPPED);
+ rc = 0;
+out_put:
+ llc_sap_put(sap);
+out:
+ dev_put(dev);
+ release_sock(sk);
+ return rc;
+}
+
+/**
+ * llc_ui_shutdown - shutdown a connect llc2 socket.
+ * @sock: Socket to shutdown.
+ * @how: What part of the socket to shutdown.
+ *
+ * Shutdown a connected llc2 socket. Currently this function only supports
+ * shutting down both sends and receives (2), we could probably make this
+ * function such that a user can shutdown only half the connection but not
+ * right now.
+ * Returns: 0 upon success, negative otherwise.
+ */
+static int llc_ui_shutdown(struct socket *sock, int how)
+{
+ struct sock *sk = sock->sk;
+ int rc = -ENOTCONN;
+
+ lock_sock(sk);
+ if (unlikely(sk->sk_state != TCP_ESTABLISHED))
+ goto out;
+ rc = -EINVAL;
+ if (how != 2)
+ goto out;
+ rc = llc_send_disc(sk);
+ if (!rc)
+ rc = llc_ui_wait_for_disc(sk, sk->sk_rcvtimeo);
+ /* Wake up anyone sleeping in poll */
+ sk->sk_state_change(sk);
+out:
+ release_sock(sk);
+ return rc;
+}
+
+/**
+ * llc_ui_connect - Connect to a remote llc2 mac + sap.
+ * @sock: Socket which will be connected to the remote destination.
+ * @uaddr: Remote and possibly the local address of the new connection.
+ * @addrlen: Size of uaddr structure.
+ * @flags: Operational flags specified by the user.
+ *
+ * Connect to a remote llc2 mac + sap. The caller must specify the
+ * destination mac and address to connect to. If the user hasn't previously
+ * called bind(2) with a smac the address of the first interface of the
+ * specified arp type will be used.
+ * This function will autobind if user did not previously call bind.
+ * Returns: 0 upon success, negative otherwise.
+ */
+static int llc_ui_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addrlen, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ struct sockaddr_llc *addr = (struct sockaddr_llc *)uaddr;
+ int rc = -EINVAL;
+
+ lock_sock(sk);
+ if (unlikely(addrlen != sizeof(*addr)))
+ goto out;
+ rc = -EAFNOSUPPORT;
+ if (unlikely(addr->sllc_family != AF_LLC))
+ goto out;
+ if (unlikely(sk->sk_type != SOCK_STREAM))
+ goto out;
+ rc = -EALREADY;
+ if (unlikely(sock->state == SS_CONNECTING))
+ goto out;
+ /* bind connection to sap if user hasn't done it. */
+ if (sock_flag(sk, SOCK_ZAPPED)) {
+ /* bind to sap with null dev, exclusive */
+ rc = llc_ui_autobind(sock, addr);
+ if (rc)
+ goto out;
+ }
+ llc->daddr.lsap = addr->sllc_sap;
+ memcpy(llc->daddr.mac, addr->sllc_mac, IFHWADDRLEN);
+ sock->state = SS_CONNECTING;
+ sk->sk_state = TCP_SYN_SENT;
+ llc->link = llc_ui_next_link_no(llc->sap->laddr.lsap);
+ rc = llc_establish_connection(sk, llc->dev->dev_addr,
+ addr->sllc_mac, addr->sllc_sap);
+ if (rc) {
+ dprintk("%s: llc_ui_send_conn failed :-(\n", __func__);
+ sock->state = SS_UNCONNECTED;
+ sk->sk_state = TCP_CLOSE;
+ goto out;
+ }
+
+ if (sk->sk_state == TCP_SYN_SENT) {
+ const long timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+ if (!timeo || !llc_ui_wait_for_conn(sk, timeo))
+ goto out;
+
+ rc = sock_intr_errno(timeo);
+ if (signal_pending(current))
+ goto out;
+ }
+
+ if (sk->sk_state == TCP_CLOSE)
+ goto sock_error;
+
+ sock->state = SS_CONNECTED;
+ rc = 0;
+out:
+ release_sock(sk);
+ return rc;
+sock_error:
+ rc = sock_error(sk) ? : -ECONNABORTED;
+ sock->state = SS_UNCONNECTED;
+ goto out;
+}
+
+/**
+ * llc_ui_listen - allow a normal socket to accept incoming connections
+ * @sock: Socket to allow incoming connections on.
+ * @backlog: Number of connections to queue.
+ *
+ * Allow a normal socket to accept incoming connections.
+ * Returns 0 upon success, negative otherwise.
+ */
+static int llc_ui_listen(struct socket *sock, int backlog)
+{
+ struct sock *sk = sock->sk;
+ int rc = -EINVAL;
+
+ lock_sock(sk);
+ if (unlikely(sock->state != SS_UNCONNECTED))
+ goto out;
+ rc = -EOPNOTSUPP;
+ if (unlikely(sk->sk_type != SOCK_STREAM))
+ goto out;
+ rc = -EAGAIN;
+ if (sock_flag(sk, SOCK_ZAPPED))
+ goto out;
+ rc = 0;
+ if (!(unsigned int)backlog) /* BSDism */
+ backlog = 1;
+ sk->sk_max_ack_backlog = backlog;
+ if (sk->sk_state != TCP_LISTEN) {
+ sk->sk_ack_backlog = 0;
+ sk->sk_state = TCP_LISTEN;
+ }
+ sk->sk_socket->flags |= __SO_ACCEPTCON;
+out:
+ release_sock(sk);
+ return rc;
+}
+
+static int llc_ui_wait_for_disc(struct sock *sk, long timeout)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ int rc = 0;
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ while (1) {
+ if (sk_wait_event(sk, &timeout,
+ READ_ONCE(sk->sk_state) == TCP_CLOSE, &wait))
+ break;
+ rc = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+ rc = -EAGAIN;
+ if (!timeout)
+ break;
+ rc = 0;
+ }
+ remove_wait_queue(sk_sleep(sk), &wait);
+ return rc;
+}
+
+static bool llc_ui_wait_for_conn(struct sock *sk, long timeout)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ while (1) {
+ if (sk_wait_event(sk, &timeout,
+ READ_ONCE(sk->sk_state) != TCP_SYN_SENT, &wait))
+ break;
+ if (signal_pending(current) || !timeout)
+ break;
+ }
+ remove_wait_queue(sk_sleep(sk), &wait);
+ return timeout;
+}
+
+static int llc_ui_wait_for_busy_core(struct sock *sk, long timeout)
+{
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ struct llc_sock *llc = llc_sk(sk);
+ int rc;
+
+ add_wait_queue(sk_sleep(sk), &wait);
+ while (1) {
+ rc = 0;
+ if (sk_wait_event(sk, &timeout,
+ (READ_ONCE(sk->sk_shutdown) & RCV_SHUTDOWN) ||
+ (!llc_data_accept_state(llc->state) &&
+ !llc->remote_busy_flag &&
+ !llc->p_flag), &wait))
+ break;
+ rc = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+ rc = -EAGAIN;
+ if (!timeout)
+ break;
+ }
+ remove_wait_queue(sk_sleep(sk), &wait);
+ return rc;
+}
+
+static int llc_wait_data(struct sock *sk, long timeo)
+{
+ int rc;
+
+ while (1) {
+ /*
+ * POSIX 1003.1g mandates this order.
+ */
+ rc = sock_error(sk);
+ if (rc)
+ break;
+ rc = 0;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+ rc = -EAGAIN;
+ if (!timeo)
+ break;
+ rc = sock_intr_errno(timeo);
+ if (signal_pending(current))
+ break;
+ rc = 0;
+ if (sk_wait_data(sk, &timeo, NULL))
+ break;
+ }
+ return rc;
+}
+
+static void llc_cmsg_rcv(struct msghdr *msg, struct sk_buff *skb)
+{
+ struct llc_sock *llc = llc_sk(skb->sk);
+
+ if (llc->cmsg_flags & LLC_CMSG_PKTINFO) {
+ struct llc_pktinfo info;
+
+ memset(&info, 0, sizeof(info));
+ info.lpi_ifindex = llc_sk(skb->sk)->dev->ifindex;
+ llc_pdu_decode_dsap(skb, &info.lpi_sap);
+ llc_pdu_decode_da(skb, info.lpi_mac);
+ put_cmsg(msg, SOL_LLC, LLC_OPT_PKTINFO, sizeof(info), &info);
+ }
+}
+
+/**
+ * llc_ui_accept - accept a new incoming connection.
+ * @sock: Socket which connections arrive on.
+ * @newsock: Socket to move incoming connection to.
+ * @flags: User specified operational flags.
+ * @kern: If the socket is kernel internal
+ *
+ * Accept a new incoming connection.
+ * Returns 0 upon success, negative otherwise.
+ */
+static int llc_ui_accept(struct socket *sock, struct socket *newsock, int flags,
+ bool kern)
+{
+ struct sock *sk = sock->sk, *newsk;
+ struct llc_sock *llc, *newllc;
+ struct sk_buff *skb;
+ int rc = -EOPNOTSUPP;
+
+ dprintk("%s: accepting on %02X\n", __func__,
+ llc_sk(sk)->laddr.lsap);
+ lock_sock(sk);
+ if (unlikely(sk->sk_type != SOCK_STREAM))
+ goto out;
+ rc = -EINVAL;
+ if (unlikely(sock->state != SS_UNCONNECTED ||
+ sk->sk_state != TCP_LISTEN))
+ goto out;
+ /* wait for a connection to arrive. */
+ if (skb_queue_empty(&sk->sk_receive_queue)) {
+ rc = llc_wait_data(sk, sk->sk_rcvtimeo);
+ if (rc)
+ goto out;
+ }
+ dprintk("%s: got a new connection on %02X\n", __func__,
+ llc_sk(sk)->laddr.lsap);
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ rc = -EINVAL;
+ if (!skb->sk)
+ goto frees;
+ rc = 0;
+ newsk = skb->sk;
+ /* attach connection to a new socket. */
+ llc_ui_sk_init(newsock, newsk);
+ sock_reset_flag(newsk, SOCK_ZAPPED);
+ newsk->sk_state = TCP_ESTABLISHED;
+ newsock->state = SS_CONNECTED;
+ llc = llc_sk(sk);
+ newllc = llc_sk(newsk);
+ memcpy(&newllc->addr, &llc->addr, sizeof(newllc->addr));
+ newllc->link = llc_ui_next_link_no(newllc->laddr.lsap);
+
+ /* put original socket back into a clean listen state. */
+ sk->sk_state = TCP_LISTEN;
+ sk_acceptq_removed(sk);
+ dprintk("%s: ok success on %02X, client on %02X\n", __func__,
+ llc_sk(sk)->addr.sllc_sap, newllc->daddr.lsap);
+frees:
+ kfree_skb(skb);
+out:
+ release_sock(sk);
+ return rc;
+}
+
+/**
+ * llc_ui_recvmsg - copy received data to the socket user.
+ * @sock: Socket to copy data from.
+ * @msg: Various user space related information.
+ * @len: Size of user buffer.
+ * @flags: User specified flags.
+ *
+ * Copy received data to the socket user.
+ * Returns non-negative upon success, negative otherwise.
+ */
+static int llc_ui_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
+ int flags)
+{
+ DECLARE_SOCKADDR(struct sockaddr_llc *, uaddr, msg->msg_name);
+ const int nonblock = flags & MSG_DONTWAIT;
+ struct sk_buff *skb = NULL;
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ size_t copied = 0;
+ u32 peek_seq = 0;
+ u32 *seq, skb_len;
+ unsigned long used;
+ int target; /* Read at least this many bytes */
+ long timeo;
+
+ lock_sock(sk);
+ copied = -ENOTCONN;
+ if (unlikely(sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_LISTEN))
+ goto out;
+
+ timeo = sock_rcvtimeo(sk, nonblock);
+
+ seq = &llc->copied_seq;
+ if (flags & MSG_PEEK) {
+ peek_seq = llc->copied_seq;
+ seq = &peek_seq;
+ }
+
+ target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
+ copied = 0;
+
+ do {
+ u32 offset;
+
+ /*
+ * We need to check signals first, to get correct SIGURG
+ * handling. FIXME: Need to check this doesn't impact 1003.1g
+ * and move it down to the bottom of the loop
+ */
+ if (signal_pending(current)) {
+ if (copied)
+ break;
+ copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
+ break;
+ }
+
+ /* Next get a buffer. */
+
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb) {
+ offset = *seq;
+ goto found_ok_skb;
+ }
+ /* Well, if we have backlog, try to process it now yet. */
+
+ if (copied >= target && !READ_ONCE(sk->sk_backlog.tail))
+ break;
+
+ if (copied) {
+ if (sk->sk_err ||
+ sk->sk_state == TCP_CLOSE ||
+ (sk->sk_shutdown & RCV_SHUTDOWN) ||
+ !timeo ||
+ (flags & MSG_PEEK))
+ break;
+ } else {
+ if (sock_flag(sk, SOCK_DONE))
+ break;
+
+ if (sk->sk_err) {
+ copied = sock_error(sk);
+ break;
+ }
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+
+ if (sk->sk_type == SOCK_STREAM && sk->sk_state == TCP_CLOSE) {
+ if (!sock_flag(sk, SOCK_DONE)) {
+ /*
+ * This occurs when user tries to read
+ * from never connected socket.
+ */
+ copied = -ENOTCONN;
+ break;
+ }
+ break;
+ }
+ if (!timeo) {
+ copied = -EAGAIN;
+ break;
+ }
+ }
+
+ if (copied >= target) { /* Do not sleep, just process backlog. */
+ release_sock(sk);
+ lock_sock(sk);
+ } else
+ sk_wait_data(sk, &timeo, NULL);
+
+ if ((flags & MSG_PEEK) && peek_seq != llc->copied_seq) {
+ net_dbg_ratelimited("LLC(%s:%d): Application bug, race in MSG_PEEK\n",
+ current->comm,
+ task_pid_nr(current));
+ peek_seq = llc->copied_seq;
+ }
+ continue;
+ found_ok_skb:
+ skb_len = skb->len;
+ /* Ok so how much can we use? */
+ used = skb->len - offset;
+ if (len < used)
+ used = len;
+
+ if (!(flags & MSG_TRUNC)) {
+ int rc = skb_copy_datagram_msg(skb, offset, msg, used);
+ if (rc) {
+ /* Exception. Bailout! */
+ if (!copied)
+ copied = -EFAULT;
+ break;
+ }
+ }
+
+ *seq += used;
+ copied += used;
+ len -= used;
+
+ /* For non stream protcols we get one packet per recvmsg call */
+ if (sk->sk_type != SOCK_STREAM)
+ goto copy_uaddr;
+
+ if (!(flags & MSG_PEEK)) {
+ skb_unlink(skb, &sk->sk_receive_queue);
+ kfree_skb(skb);
+ *seq = 0;
+ }
+
+ /* Partial read */
+ if (used + offset < skb_len)
+ continue;
+ } while (len > 0);
+
+out:
+ release_sock(sk);
+ return copied;
+copy_uaddr:
+ if (uaddr != NULL && skb != NULL) {
+ memcpy(uaddr, llc_ui_skb_cb(skb), sizeof(*uaddr));
+ msg->msg_namelen = sizeof(*uaddr);
+ }
+ if (llc_sk(sk)->cmsg_flags)
+ llc_cmsg_rcv(msg, skb);
+
+ if (!(flags & MSG_PEEK)) {
+ skb_unlink(skb, &sk->sk_receive_queue);
+ kfree_skb(skb);
+ *seq = 0;
+ }
+
+ goto out;
+}
+
+/**
+ * llc_ui_sendmsg - Transmit data provided by the socket user.
+ * @sock: Socket to transmit data from.
+ * @msg: Various user related information.
+ * @len: Length of data to transmit.
+ *
+ * Transmit data provided by the socket user.
+ * Returns non-negative upon success, negative otherwise.
+ */
+static int llc_ui_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+ DECLARE_SOCKADDR(struct sockaddr_llc *, addr, msg->msg_name);
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ int flags = msg->msg_flags;
+ int noblock = flags & MSG_DONTWAIT;
+ int rc = -EINVAL, copied = 0, hdrlen, hh_len;
+ struct sk_buff *skb = NULL;
+ struct net_device *dev;
+ size_t size = 0;
+
+ dprintk("%s: sending from %02X to %02X\n", __func__,
+ llc->laddr.lsap, llc->daddr.lsap);
+ lock_sock(sk);
+ if (addr) {
+ if (msg->msg_namelen < sizeof(*addr))
+ goto out;
+ } else {
+ if (llc_ui_addr_null(&llc->addr))
+ goto out;
+ addr = &llc->addr;
+ }
+ /* must bind connection to sap if user hasn't done it. */
+ if (sock_flag(sk, SOCK_ZAPPED)) {
+ /* bind to sap with null dev, exclusive. */
+ rc = llc_ui_autobind(sock, addr);
+ if (rc)
+ goto out;
+ }
+ dev = llc->dev;
+ hh_len = LL_RESERVED_SPACE(dev);
+ hdrlen = llc_ui_header_len(sk, addr);
+ size = hdrlen + len;
+ size = min_t(size_t, size, READ_ONCE(dev->mtu));
+ copied = size - hdrlen;
+ rc = -EINVAL;
+ if (copied < 0)
+ goto out;
+ release_sock(sk);
+ skb = sock_alloc_send_skb(sk, hh_len + size, noblock, &rc);
+ lock_sock(sk);
+ if (!skb)
+ goto out;
+ if (sock_flag(sk, SOCK_ZAPPED) ||
+ llc->dev != dev ||
+ hdrlen != llc_ui_header_len(sk, addr) ||
+ hh_len != LL_RESERVED_SPACE(dev) ||
+ size > READ_ONCE(dev->mtu))
+ goto out;
+ skb->dev = dev;
+ skb->protocol = llc_proto_type(addr->sllc_arphrd);
+ skb_reserve(skb, hh_len + hdrlen);
+ rc = memcpy_from_msg(skb_put(skb, copied), msg, copied);
+ if (rc)
+ goto out;
+ if (sk->sk_type == SOCK_DGRAM || addr->sllc_ua) {
+ llc_build_and_send_ui_pkt(llc->sap, skb, addr->sllc_mac,
+ addr->sllc_sap);
+ skb = NULL;
+ goto out;
+ }
+ if (addr->sllc_test) {
+ llc_build_and_send_test_pkt(llc->sap, skb, addr->sllc_mac,
+ addr->sllc_sap);
+ skb = NULL;
+ goto out;
+ }
+ if (addr->sllc_xid) {
+ llc_build_and_send_xid_pkt(llc->sap, skb, addr->sllc_mac,
+ addr->sllc_sap);
+ skb = NULL;
+ goto out;
+ }
+ rc = -ENOPROTOOPT;
+ if (!(sk->sk_type == SOCK_STREAM && !addr->sllc_ua))
+ goto out;
+ rc = llc_ui_send_data(sk, skb, noblock);
+ skb = NULL;
+out:
+ kfree_skb(skb);
+ if (rc)
+ dprintk("%s: failed sending from %02X to %02X: %d\n",
+ __func__, llc->laddr.lsap, llc->daddr.lsap, rc);
+ release_sock(sk);
+ return rc ? : copied;
+}
+
+/**
+ * llc_ui_getname - return the address info of a socket
+ * @sock: Socket to get address of.
+ * @uaddr: Address structure to return information.
+ * @peer: Does user want local or remote address information.
+ *
+ * Return the address information of a socket.
+ */
+static int llc_ui_getname(struct socket *sock, struct sockaddr *uaddr,
+ int peer)
+{
+ struct sockaddr_llc sllc;
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ int rc = -EBADF;
+
+ memset(&sllc, 0, sizeof(sllc));
+ lock_sock(sk);
+ if (sock_flag(sk, SOCK_ZAPPED))
+ goto out;
+ if (peer) {
+ rc = -ENOTCONN;
+ if (sk->sk_state != TCP_ESTABLISHED)
+ goto out;
+ if(llc->dev)
+ sllc.sllc_arphrd = llc->dev->type;
+ sllc.sllc_sap = llc->daddr.lsap;
+ memcpy(&sllc.sllc_mac, &llc->daddr.mac, IFHWADDRLEN);
+ } else {
+ rc = -EINVAL;
+ if (!llc->sap)
+ goto out;
+ sllc.sllc_sap = llc->sap->laddr.lsap;
+
+ if (llc->dev) {
+ sllc.sllc_arphrd = llc->dev->type;
+ memcpy(&sllc.sllc_mac, llc->dev->dev_addr,
+ IFHWADDRLEN);
+ }
+ }
+ sllc.sllc_family = AF_LLC;
+ memcpy(uaddr, &sllc, sizeof(sllc));
+ rc = sizeof(sllc);
+out:
+ release_sock(sk);
+ return rc;
+}
+
+/**
+ * llc_ui_ioctl - io controls for PF_LLC
+ * @sock: Socket to get/set info
+ * @cmd: command
+ * @arg: optional argument for cmd
+ *
+ * get/set info on llc sockets
+ */
+static int llc_ui_ioctl(struct socket *sock, unsigned int cmd,
+ unsigned long arg)
+{
+ return -ENOIOCTLCMD;
+}
+
+/**
+ * llc_ui_setsockopt - set various connection specific parameters.
+ * @sock: Socket to set options on.
+ * @level: Socket level user is requesting operations on.
+ * @optname: Operation name.
+ * @optval: User provided operation data.
+ * @optlen: Length of optval.
+ *
+ * Set various connection specific parameters.
+ */
+static int llc_ui_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ unsigned int opt;
+ int rc = -EINVAL;
+
+ lock_sock(sk);
+ if (unlikely(level != SOL_LLC || optlen != sizeof(int)))
+ goto out;
+ rc = copy_from_sockptr(&opt, optval, sizeof(opt));
+ if (rc)
+ goto out;
+ rc = -EINVAL;
+ switch (optname) {
+ case LLC_OPT_RETRY:
+ if (opt > LLC_OPT_MAX_RETRY)
+ goto out;
+ llc->n2 = opt;
+ break;
+ case LLC_OPT_SIZE:
+ if (opt > LLC_OPT_MAX_SIZE)
+ goto out;
+ llc->n1 = opt;
+ break;
+ case LLC_OPT_ACK_TMR_EXP:
+ if (opt > LLC_OPT_MAX_ACK_TMR_EXP)
+ goto out;
+ llc->ack_timer.expire = opt * HZ;
+ break;
+ case LLC_OPT_P_TMR_EXP:
+ if (opt > LLC_OPT_MAX_P_TMR_EXP)
+ goto out;
+ llc->pf_cycle_timer.expire = opt * HZ;
+ break;
+ case LLC_OPT_REJ_TMR_EXP:
+ if (opt > LLC_OPT_MAX_REJ_TMR_EXP)
+ goto out;
+ llc->rej_sent_timer.expire = opt * HZ;
+ break;
+ case LLC_OPT_BUSY_TMR_EXP:
+ if (opt > LLC_OPT_MAX_BUSY_TMR_EXP)
+ goto out;
+ llc->busy_state_timer.expire = opt * HZ;
+ break;
+ case LLC_OPT_TX_WIN:
+ if (opt > LLC_OPT_MAX_WIN)
+ goto out;
+ llc->k = opt;
+ break;
+ case LLC_OPT_RX_WIN:
+ if (opt > LLC_OPT_MAX_WIN)
+ goto out;
+ llc->rw = opt;
+ break;
+ case LLC_OPT_PKTINFO:
+ if (opt)
+ llc->cmsg_flags |= LLC_CMSG_PKTINFO;
+ else
+ llc->cmsg_flags &= ~LLC_CMSG_PKTINFO;
+ break;
+ default:
+ rc = -ENOPROTOOPT;
+ goto out;
+ }
+ rc = 0;
+out:
+ release_sock(sk);
+ return rc;
+}
+
+/**
+ * llc_ui_getsockopt - get connection specific socket info
+ * @sock: Socket to get information from.
+ * @level: Socket level user is requesting operations on.
+ * @optname: Operation name.
+ * @optval: Variable to return operation data in.
+ * @optlen: Length of optval.
+ *
+ * Get connection specific socket information.
+ */
+static int llc_ui_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct sock *sk = sock->sk;
+ struct llc_sock *llc = llc_sk(sk);
+ int val = 0, len = 0, rc = -EINVAL;
+
+ lock_sock(sk);
+ if (unlikely(level != SOL_LLC))
+ goto out;
+ rc = get_user(len, optlen);
+ if (rc)
+ goto out;
+ rc = -EINVAL;
+ if (len != sizeof(int))
+ goto out;
+ switch (optname) {
+ case LLC_OPT_RETRY:
+ val = llc->n2; break;
+ case LLC_OPT_SIZE:
+ val = llc->n1; break;
+ case LLC_OPT_ACK_TMR_EXP:
+ val = llc->ack_timer.expire / HZ; break;
+ case LLC_OPT_P_TMR_EXP:
+ val = llc->pf_cycle_timer.expire / HZ; break;
+ case LLC_OPT_REJ_TMR_EXP:
+ val = llc->rej_sent_timer.expire / HZ; break;
+ case LLC_OPT_BUSY_TMR_EXP:
+ val = llc->busy_state_timer.expire / HZ; break;
+ case LLC_OPT_TX_WIN:
+ val = llc->k; break;
+ case LLC_OPT_RX_WIN:
+ val = llc->rw; break;
+ case LLC_OPT_PKTINFO:
+ val = (llc->cmsg_flags & LLC_CMSG_PKTINFO) != 0;
+ break;
+ default:
+ rc = -ENOPROTOOPT;
+ goto out;
+ }
+ rc = 0;
+ if (put_user(len, optlen) || copy_to_user(optval, &val, len))
+ rc = -EFAULT;
+out:
+ release_sock(sk);
+ return rc;
+}
+
+static const struct net_proto_family llc_ui_family_ops = {
+ .family = PF_LLC,
+ .create = llc_ui_create,
+ .owner = THIS_MODULE,
+};
+
+static const struct proto_ops llc_ui_ops = {
+ .family = PF_LLC,
+ .owner = THIS_MODULE,
+ .release = llc_ui_release,
+ .bind = llc_ui_bind,
+ .connect = llc_ui_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = llc_ui_accept,
+ .getname = llc_ui_getname,
+ .poll = datagram_poll,
+ .ioctl = llc_ui_ioctl,
+ .listen = llc_ui_listen,
+ .shutdown = llc_ui_shutdown,
+ .setsockopt = llc_ui_setsockopt,
+ .getsockopt = llc_ui_getsockopt,
+ .sendmsg = llc_ui_sendmsg,
+ .recvmsg = llc_ui_recvmsg,
+ .mmap = sock_no_mmap,
+};
+
+static const char llc_proc_err_msg[] __initconst =
+ KERN_CRIT "LLC: Unable to register the proc_fs entries\n";
+static const char llc_sysctl_err_msg[] __initconst =
+ KERN_CRIT "LLC: Unable to register the sysctl entries\n";
+static const char llc_sock_err_msg[] __initconst =
+ KERN_CRIT "LLC: Unable to register the network family\n";
+
+static int __init llc2_init(void)
+{
+ int rc = proto_register(&llc_proto, 0);
+
+ if (rc != 0)
+ goto out;
+
+ llc_build_offset_table();
+ llc_station_init();
+ llc_ui_sap_last_autoport = LLC_SAP_DYN_START;
+ rc = llc_proc_init();
+ if (rc != 0) {
+ printk(llc_proc_err_msg);
+ goto out_station;
+ }
+ rc = llc_sysctl_init();
+ if (rc) {
+ printk(llc_sysctl_err_msg);
+ goto out_proc;
+ }
+ rc = sock_register(&llc_ui_family_ops);
+ if (rc) {
+ printk(llc_sock_err_msg);
+ goto out_sysctl;
+ }
+ llc_add_pack(LLC_DEST_SAP, llc_sap_handler);
+ llc_add_pack(LLC_DEST_CONN, llc_conn_handler);
+out:
+ return rc;
+out_sysctl:
+ llc_sysctl_exit();
+out_proc:
+ llc_proc_exit();
+out_station:
+ llc_station_exit();
+ proto_unregister(&llc_proto);
+ goto out;
+}
+
+static void __exit llc2_exit(void)
+{
+ llc_station_exit();
+ llc_remove_pack(LLC_DEST_SAP);
+ llc_remove_pack(LLC_DEST_CONN);
+ sock_unregister(PF_LLC);
+ llc_proc_exit();
+ llc_sysctl_exit();
+ proto_unregister(&llc_proto);
+}
+
+module_init(llc2_init);
+module_exit(llc2_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003");
+MODULE_DESCRIPTION("IEEE 802.2 PF_LLC support");
+MODULE_ALIAS_NETPROTO(PF_LLC);