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-rw-r--r--net/netrom/af_netrom.c1536
1 files changed, 1536 insertions, 0 deletions
diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c
new file mode 100644
index 0000000000..96e91ab715
--- /dev/null
+++ b/net/netrom/af_netrom.c
@@ -0,0 +1,1536 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
+ * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
+ * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
+ */
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/capability.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/stat.h>
+#include <net/ax25.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/skbuff.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <linux/uaccess.h>
+#include <linux/fcntl.h>
+#include <linux/termios.h> /* For TIOCINQ/OUTQ */
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <net/netrom.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <net/ip.h>
+#include <net/tcp_states.h>
+#include <net/arp.h>
+#include <linux/init.h>
+
+static int nr_ndevs = 4;
+
+int sysctl_netrom_default_path_quality = NR_DEFAULT_QUAL;
+int sysctl_netrom_obsolescence_count_initialiser = NR_DEFAULT_OBS;
+int sysctl_netrom_network_ttl_initialiser = NR_DEFAULT_TTL;
+int sysctl_netrom_transport_timeout = NR_DEFAULT_T1;
+int sysctl_netrom_transport_maximum_tries = NR_DEFAULT_N2;
+int sysctl_netrom_transport_acknowledge_delay = NR_DEFAULT_T2;
+int sysctl_netrom_transport_busy_delay = NR_DEFAULT_T4;
+int sysctl_netrom_transport_requested_window_size = NR_DEFAULT_WINDOW;
+int sysctl_netrom_transport_no_activity_timeout = NR_DEFAULT_IDLE;
+int sysctl_netrom_routing_control = NR_DEFAULT_ROUTING;
+int sysctl_netrom_link_fails_count = NR_DEFAULT_FAILS;
+int sysctl_netrom_reset_circuit = NR_DEFAULT_RESET;
+
+static unsigned short circuit = 0x101;
+
+static HLIST_HEAD(nr_list);
+static DEFINE_SPINLOCK(nr_list_lock);
+
+static const struct proto_ops nr_proto_ops;
+
+/*
+ * NETROM network devices are virtual network devices encapsulating NETROM
+ * frames into AX.25 which will be sent through an AX.25 device, so form a
+ * special "super class" of normal net devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key nr_netdev_xmit_lock_key;
+static struct lock_class_key nr_netdev_addr_lock_key;
+
+static void nr_set_lockdep_one(struct net_device *dev,
+ struct netdev_queue *txq,
+ void *_unused)
+{
+ lockdep_set_class(&txq->_xmit_lock, &nr_netdev_xmit_lock_key);
+}
+
+static void nr_set_lockdep_key(struct net_device *dev)
+{
+ lockdep_set_class(&dev->addr_list_lock, &nr_netdev_addr_lock_key);
+ netdev_for_each_tx_queue(dev, nr_set_lockdep_one, NULL);
+}
+
+/*
+ * Socket removal during an interrupt is now safe.
+ */
+static void nr_remove_socket(struct sock *sk)
+{
+ spin_lock_bh(&nr_list_lock);
+ sk_del_node_init(sk);
+ spin_unlock_bh(&nr_list_lock);
+}
+
+/*
+ * Kill all bound sockets on a dropped device.
+ */
+static void nr_kill_by_device(struct net_device *dev)
+{
+ struct sock *s;
+
+ spin_lock_bh(&nr_list_lock);
+ sk_for_each(s, &nr_list)
+ if (nr_sk(s)->device == dev)
+ nr_disconnect(s, ENETUNREACH);
+ spin_unlock_bh(&nr_list_lock);
+}
+
+/*
+ * Handle device status changes.
+ */
+static int nr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (!net_eq(dev_net(dev), &init_net))
+ return NOTIFY_DONE;
+
+ if (event != NETDEV_DOWN)
+ return NOTIFY_DONE;
+
+ nr_kill_by_device(dev);
+ nr_rt_device_down(dev);
+
+ return NOTIFY_DONE;
+}
+
+/*
+ * Add a socket to the bound sockets list.
+ */
+static void nr_insert_socket(struct sock *sk)
+{
+ spin_lock_bh(&nr_list_lock);
+ sk_add_node(sk, &nr_list);
+ spin_unlock_bh(&nr_list_lock);
+}
+
+/*
+ * Find a socket that wants to accept the Connect Request we just
+ * received.
+ */
+static struct sock *nr_find_listener(ax25_address *addr)
+{
+ struct sock *s;
+
+ spin_lock_bh(&nr_list_lock);
+ sk_for_each(s, &nr_list)
+ if (!ax25cmp(&nr_sk(s)->source_addr, addr) &&
+ s->sk_state == TCP_LISTEN) {
+ sock_hold(s);
+ goto found;
+ }
+ s = NULL;
+found:
+ spin_unlock_bh(&nr_list_lock);
+ return s;
+}
+
+/*
+ * Find a connected NET/ROM socket given my circuit IDs.
+ */
+static struct sock *nr_find_socket(unsigned char index, unsigned char id)
+{
+ struct sock *s;
+
+ spin_lock_bh(&nr_list_lock);
+ sk_for_each(s, &nr_list) {
+ struct nr_sock *nr = nr_sk(s);
+
+ if (nr->my_index == index && nr->my_id == id) {
+ sock_hold(s);
+ goto found;
+ }
+ }
+ s = NULL;
+found:
+ spin_unlock_bh(&nr_list_lock);
+ return s;
+}
+
+/*
+ * Find a connected NET/ROM socket given their circuit IDs.
+ */
+static struct sock *nr_find_peer(unsigned char index, unsigned char id,
+ ax25_address *dest)
+{
+ struct sock *s;
+
+ spin_lock_bh(&nr_list_lock);
+ sk_for_each(s, &nr_list) {
+ struct nr_sock *nr = nr_sk(s);
+
+ if (nr->your_index == index && nr->your_id == id &&
+ !ax25cmp(&nr->dest_addr, dest)) {
+ sock_hold(s);
+ goto found;
+ }
+ }
+ s = NULL;
+found:
+ spin_unlock_bh(&nr_list_lock);
+ return s;
+}
+
+/*
+ * Find next free circuit ID.
+ */
+static unsigned short nr_find_next_circuit(void)
+{
+ unsigned short id = circuit;
+ unsigned char i, j;
+ struct sock *sk;
+
+ for (;;) {
+ i = id / 256;
+ j = id % 256;
+
+ if (i != 0 && j != 0) {
+ if ((sk=nr_find_socket(i, j)) == NULL)
+ break;
+ sock_put(sk);
+ }
+
+ id++;
+ }
+
+ return id;
+}
+
+/*
+ * Deferred destroy.
+ */
+void nr_destroy_socket(struct sock *);
+
+/*
+ * Handler for deferred kills.
+ */
+static void nr_destroy_timer(struct timer_list *t)
+{
+ struct sock *sk = from_timer(sk, t, sk_timer);
+ bh_lock_sock(sk);
+ sock_hold(sk);
+ nr_destroy_socket(sk);
+ bh_unlock_sock(sk);
+ sock_put(sk);
+}
+
+/*
+ * This is called from user mode and the timers. Thus it protects itself
+ * against interrupt users but doesn't worry about being called during
+ * work. Once it is removed from the queue no interrupt or bottom half
+ * will touch it and we are (fairly 8-) ) safe.
+ */
+void nr_destroy_socket(struct sock *sk)
+{
+ struct sk_buff *skb;
+
+ nr_remove_socket(sk);
+
+ nr_stop_heartbeat(sk);
+ nr_stop_t1timer(sk);
+ nr_stop_t2timer(sk);
+ nr_stop_t4timer(sk);
+ nr_stop_idletimer(sk);
+
+ nr_clear_queues(sk); /* Flush the queues */
+
+ while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ if (skb->sk != sk) { /* A pending connection */
+ /* Queue the unaccepted socket for death */
+ sock_set_flag(skb->sk, SOCK_DEAD);
+ nr_start_heartbeat(skb->sk);
+ nr_sk(skb->sk)->state = NR_STATE_0;
+ }
+
+ kfree_skb(skb);
+ }
+
+ if (sk_has_allocations(sk)) {
+ /* Defer: outstanding buffers */
+ sk->sk_timer.function = nr_destroy_timer;
+ sk->sk_timer.expires = jiffies + 2 * HZ;
+ add_timer(&sk->sk_timer);
+ } else
+ sock_put(sk);
+}
+
+/*
+ * Handling for system calls applied via the various interfaces to a
+ * NET/ROM socket object.
+ */
+
+static int nr_setsockopt(struct socket *sock, int level, int optname,
+ sockptr_t optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ unsigned int opt;
+
+ if (level != SOL_NETROM)
+ return -ENOPROTOOPT;
+
+ if (optlen < sizeof(unsigned int))
+ return -EINVAL;
+
+ if (copy_from_sockptr(&opt, optval, sizeof(opt)))
+ return -EFAULT;
+
+ switch (optname) {
+ case NETROM_T1:
+ if (opt < 1 || opt > UINT_MAX / HZ)
+ return -EINVAL;
+ nr->t1 = opt * HZ;
+ return 0;
+
+ case NETROM_T2:
+ if (opt < 1 || opt > UINT_MAX / HZ)
+ return -EINVAL;
+ nr->t2 = opt * HZ;
+ return 0;
+
+ case NETROM_N2:
+ if (opt < 1 || opt > 31)
+ return -EINVAL;
+ nr->n2 = opt;
+ return 0;
+
+ case NETROM_T4:
+ if (opt < 1 || opt > UINT_MAX / HZ)
+ return -EINVAL;
+ nr->t4 = opt * HZ;
+ return 0;
+
+ case NETROM_IDLE:
+ if (opt > UINT_MAX / (60 * HZ))
+ return -EINVAL;
+ nr->idle = opt * 60 * HZ;
+ return 0;
+
+ default:
+ return -ENOPROTOOPT;
+ }
+}
+
+static int nr_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ int val = 0;
+ int len;
+
+ if (level != SOL_NETROM)
+ return -ENOPROTOOPT;
+
+ if (get_user(len, optlen))
+ return -EFAULT;
+
+ if (len < 0)
+ return -EINVAL;
+
+ switch (optname) {
+ case NETROM_T1:
+ val = nr->t1 / HZ;
+ break;
+
+ case NETROM_T2:
+ val = nr->t2 / HZ;
+ break;
+
+ case NETROM_N2:
+ val = nr->n2;
+ break;
+
+ case NETROM_T4:
+ val = nr->t4 / HZ;
+ break;
+
+ case NETROM_IDLE:
+ val = nr->idle / (60 * HZ);
+ break;
+
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ len = min_t(unsigned int, len, sizeof(int));
+
+ if (put_user(len, optlen))
+ return -EFAULT;
+
+ return copy_to_user(optval, &val, len) ? -EFAULT : 0;
+}
+
+static int nr_listen(struct socket *sock, int backlog)
+{
+ struct sock *sk = sock->sk;
+
+ lock_sock(sk);
+ if (sock->state != SS_UNCONNECTED) {
+ release_sock(sk);
+ return -EINVAL;
+ }
+
+ if (sk->sk_state != TCP_LISTEN) {
+ memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
+ sk->sk_max_ack_backlog = backlog;
+ sk->sk_state = TCP_LISTEN;
+ release_sock(sk);
+ return 0;
+ }
+ release_sock(sk);
+
+ return -EOPNOTSUPP;
+}
+
+static struct proto nr_proto = {
+ .name = "NETROM",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct nr_sock),
+};
+
+static int nr_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk;
+ struct nr_sock *nr;
+
+ if (!net_eq(net, &init_net))
+ return -EAFNOSUPPORT;
+
+ if (sock->type != SOCK_SEQPACKET || protocol != 0)
+ return -ESOCKTNOSUPPORT;
+
+ sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
+ if (sk == NULL)
+ return -ENOMEM;
+
+ nr = nr_sk(sk);
+
+ sock_init_data(sock, sk);
+
+ sock->ops = &nr_proto_ops;
+ sk->sk_protocol = protocol;
+
+ skb_queue_head_init(&nr->ack_queue);
+ skb_queue_head_init(&nr->reseq_queue);
+ skb_queue_head_init(&nr->frag_queue);
+
+ nr_init_timers(sk);
+
+ nr->t1 =
+ msecs_to_jiffies(sysctl_netrom_transport_timeout);
+ nr->t2 =
+ msecs_to_jiffies(sysctl_netrom_transport_acknowledge_delay);
+ nr->n2 =
+ msecs_to_jiffies(sysctl_netrom_transport_maximum_tries);
+ nr->t4 =
+ msecs_to_jiffies(sysctl_netrom_transport_busy_delay);
+ nr->idle =
+ msecs_to_jiffies(sysctl_netrom_transport_no_activity_timeout);
+ nr->window = sysctl_netrom_transport_requested_window_size;
+
+ nr->bpqext = 1;
+ nr->state = NR_STATE_0;
+
+ return 0;
+}
+
+static struct sock *nr_make_new(struct sock *osk)
+{
+ struct sock *sk;
+ struct nr_sock *nr, *onr;
+
+ if (osk->sk_type != SOCK_SEQPACKET)
+ return NULL;
+
+ sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
+ if (sk == NULL)
+ return NULL;
+
+ nr = nr_sk(sk);
+
+ sock_init_data(NULL, sk);
+
+ sk->sk_type = osk->sk_type;
+ sk->sk_priority = osk->sk_priority;
+ sk->sk_protocol = osk->sk_protocol;
+ sk->sk_rcvbuf = osk->sk_rcvbuf;
+ sk->sk_sndbuf = osk->sk_sndbuf;
+ sk->sk_state = TCP_ESTABLISHED;
+ sock_copy_flags(sk, osk);
+
+ skb_queue_head_init(&nr->ack_queue);
+ skb_queue_head_init(&nr->reseq_queue);
+ skb_queue_head_init(&nr->frag_queue);
+
+ nr_init_timers(sk);
+
+ onr = nr_sk(osk);
+
+ nr->t1 = onr->t1;
+ nr->t2 = onr->t2;
+ nr->n2 = onr->n2;
+ nr->t4 = onr->t4;
+ nr->idle = onr->idle;
+ nr->window = onr->window;
+
+ nr->device = onr->device;
+ nr->bpqext = onr->bpqext;
+
+ return sk;
+}
+
+static int nr_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr;
+
+ if (sk == NULL) return 0;
+
+ sock_hold(sk);
+ sock_orphan(sk);
+ lock_sock(sk);
+ nr = nr_sk(sk);
+
+ switch (nr->state) {
+ case NR_STATE_0:
+ case NR_STATE_1:
+ case NR_STATE_2:
+ nr_disconnect(sk, 0);
+ nr_destroy_socket(sk);
+ break;
+
+ case NR_STATE_3:
+ nr_clear_queues(sk);
+ nr->n2count = 0;
+ nr_write_internal(sk, NR_DISCREQ);
+ nr_start_t1timer(sk);
+ nr_stop_t2timer(sk);
+ nr_stop_t4timer(sk);
+ nr_stop_idletimer(sk);
+ nr->state = NR_STATE_2;
+ sk->sk_state = TCP_CLOSE;
+ sk->sk_shutdown |= SEND_SHUTDOWN;
+ sk->sk_state_change(sk);
+ sock_set_flag(sk, SOCK_DESTROY);
+ break;
+
+ default:
+ break;
+ }
+
+ sock->sk = NULL;
+ release_sock(sk);
+ sock_put(sk);
+
+ return 0;
+}
+
+static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
+ struct net_device *dev;
+ ax25_uid_assoc *user;
+ ax25_address *source;
+
+ lock_sock(sk);
+ if (!sock_flag(sk, SOCK_ZAPPED)) {
+ release_sock(sk);
+ return -EINVAL;
+ }
+ if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
+ release_sock(sk);
+ return -EINVAL;
+ }
+ if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
+ release_sock(sk);
+ return -EINVAL;
+ }
+ if (addr->fsa_ax25.sax25_family != AF_NETROM) {
+ release_sock(sk);
+ return -EINVAL;
+ }
+ if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
+ release_sock(sk);
+ return -EADDRNOTAVAIL;
+ }
+
+ /*
+ * Only the super user can set an arbitrary user callsign.
+ */
+ if (addr->fsa_ax25.sax25_ndigis == 1) {
+ if (!capable(CAP_NET_BIND_SERVICE)) {
+ dev_put(dev);
+ release_sock(sk);
+ return -EPERM;
+ }
+ nr->user_addr = addr->fsa_digipeater[0];
+ nr->source_addr = addr->fsa_ax25.sax25_call;
+ } else {
+ source = &addr->fsa_ax25.sax25_call;
+
+ user = ax25_findbyuid(current_euid());
+ if (user) {
+ nr->user_addr = user->call;
+ ax25_uid_put(user);
+ } else {
+ if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
+ release_sock(sk);
+ dev_put(dev);
+ return -EPERM;
+ }
+ nr->user_addr = *source;
+ }
+
+ nr->source_addr = *source;
+ }
+
+ nr->device = dev;
+ nr_insert_socket(sk);
+
+ sock_reset_flag(sk, SOCK_ZAPPED);
+ dev_put(dev);
+ release_sock(sk);
+
+ return 0;
+}
+
+static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
+ const ax25_address *source = NULL;
+ ax25_uid_assoc *user;
+ struct net_device *dev;
+ int err = 0;
+
+ lock_sock(sk);
+ if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
+ sock->state = SS_CONNECTED;
+ goto out_release; /* Connect completed during a ERESTARTSYS event */
+ }
+
+ if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
+ sock->state = SS_UNCONNECTED;
+ err = -ECONNREFUSED;
+ goto out_release;
+ }
+
+ if (sk->sk_state == TCP_ESTABLISHED) {
+ err = -EISCONN; /* No reconnect on a seqpacket socket */
+ goto out_release;
+ }
+
+ if (sock->state == SS_CONNECTING) {
+ err = -EALREADY;
+ goto out_release;
+ }
+
+ sk->sk_state = TCP_CLOSE;
+ sock->state = SS_UNCONNECTED;
+
+ if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
+ err = -EINVAL;
+ goto out_release;
+ }
+ if (addr->sax25_family != AF_NETROM) {
+ err = -EINVAL;
+ goto out_release;
+ }
+ if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */
+ sock_reset_flag(sk, SOCK_ZAPPED);
+
+ if ((dev = nr_dev_first()) == NULL) {
+ err = -ENETUNREACH;
+ goto out_release;
+ }
+ source = (const ax25_address *)dev->dev_addr;
+
+ user = ax25_findbyuid(current_euid());
+ if (user) {
+ nr->user_addr = user->call;
+ ax25_uid_put(user);
+ } else {
+ if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
+ dev_put(dev);
+ err = -EPERM;
+ goto out_release;
+ }
+ nr->user_addr = *source;
+ }
+
+ nr->source_addr = *source;
+ nr->device = dev;
+
+ dev_put(dev);
+ nr_insert_socket(sk); /* Finish the bind */
+ }
+
+ nr->dest_addr = addr->sax25_call;
+
+ release_sock(sk);
+ circuit = nr_find_next_circuit();
+ lock_sock(sk);
+
+ nr->my_index = circuit / 256;
+ nr->my_id = circuit % 256;
+
+ circuit++;
+
+ /* Move to connecting socket, start sending Connect Requests */
+ sock->state = SS_CONNECTING;
+ sk->sk_state = TCP_SYN_SENT;
+
+ nr_establish_data_link(sk);
+
+ nr->state = NR_STATE_1;
+
+ nr_start_heartbeat(sk);
+
+ /* Now the loop */
+ if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
+ err = -EINPROGRESS;
+ goto out_release;
+ }
+
+ /*
+ * A Connect Ack with Choke or timeout or failed routing will go to
+ * closed.
+ */
+ if (sk->sk_state == TCP_SYN_SENT) {
+ DEFINE_WAIT(wait);
+
+ for (;;) {
+ prepare_to_wait(sk_sleep(sk), &wait,
+ TASK_INTERRUPTIBLE);
+ if (sk->sk_state != TCP_SYN_SENT)
+ break;
+ if (!signal_pending(current)) {
+ release_sock(sk);
+ schedule();
+ lock_sock(sk);
+ continue;
+ }
+ err = -ERESTARTSYS;
+ break;
+ }
+ finish_wait(sk_sleep(sk), &wait);
+ if (err)
+ goto out_release;
+ }
+
+ if (sk->sk_state != TCP_ESTABLISHED) {
+ sock->state = SS_UNCONNECTED;
+ err = sock_error(sk); /* Always set at this point */
+ goto out_release;
+ }
+
+ sock->state = SS_CONNECTED;
+
+out_release:
+ release_sock(sk);
+
+ return err;
+}
+
+static int nr_accept(struct socket *sock, struct socket *newsock, int flags,
+ bool kern)
+{
+ struct sk_buff *skb;
+ struct sock *newsk;
+ DEFINE_WAIT(wait);
+ struct sock *sk;
+ int err = 0;
+
+ if ((sk = sock->sk) == NULL)
+ return -EINVAL;
+
+ lock_sock(sk);
+ if (sk->sk_type != SOCK_SEQPACKET) {
+ err = -EOPNOTSUPP;
+ goto out_release;
+ }
+
+ if (sk->sk_state != TCP_LISTEN) {
+ err = -EINVAL;
+ goto out_release;
+ }
+
+ /*
+ * The write queue this time is holding sockets ready to use
+ * hooked into the SABM we saved
+ */
+ for (;;) {
+ prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ if (skb)
+ break;
+
+ if (flags & O_NONBLOCK) {
+ err = -EWOULDBLOCK;
+ break;
+ }
+ if (!signal_pending(current)) {
+ release_sock(sk);
+ schedule();
+ lock_sock(sk);
+ continue;
+ }
+ err = -ERESTARTSYS;
+ break;
+ }
+ finish_wait(sk_sleep(sk), &wait);
+ if (err)
+ goto out_release;
+
+ newsk = skb->sk;
+ sock_graft(newsk, newsock);
+
+ /* Now attach up the new socket */
+ kfree_skb(skb);
+ sk_acceptq_removed(sk);
+
+out_release:
+ release_sock(sk);
+
+ return err;
+}
+
+static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
+ int peer)
+{
+ struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ int uaddr_len;
+
+ memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
+
+ lock_sock(sk);
+ if (peer != 0) {
+ if (sk->sk_state != TCP_ESTABLISHED) {
+ release_sock(sk);
+ return -ENOTCONN;
+ }
+ sax->fsa_ax25.sax25_family = AF_NETROM;
+ sax->fsa_ax25.sax25_ndigis = 1;
+ sax->fsa_ax25.sax25_call = nr->user_addr;
+ memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
+ sax->fsa_digipeater[0] = nr->dest_addr;
+ uaddr_len = sizeof(struct full_sockaddr_ax25);
+ } else {
+ sax->fsa_ax25.sax25_family = AF_NETROM;
+ sax->fsa_ax25.sax25_ndigis = 0;
+ sax->fsa_ax25.sax25_call = nr->source_addr;
+ uaddr_len = sizeof(struct sockaddr_ax25);
+ }
+ release_sock(sk);
+
+ return uaddr_len;
+}
+
+int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sock *sk;
+ struct sock *make;
+ struct nr_sock *nr_make;
+ ax25_address *src, *dest, *user;
+ unsigned short circuit_index, circuit_id;
+ unsigned short peer_circuit_index, peer_circuit_id;
+ unsigned short frametype, flags, window, timeout;
+ int ret;
+
+ skb_orphan(skb);
+
+ /*
+ * skb->data points to the netrom frame start
+ */
+
+ src = (ax25_address *)(skb->data + 0);
+ dest = (ax25_address *)(skb->data + 7);
+
+ circuit_index = skb->data[15];
+ circuit_id = skb->data[16];
+ peer_circuit_index = skb->data[17];
+ peer_circuit_id = skb->data[18];
+ frametype = skb->data[19] & 0x0F;
+ flags = skb->data[19] & 0xF0;
+
+ /*
+ * Check for an incoming IP over NET/ROM frame.
+ */
+ if (frametype == NR_PROTOEXT &&
+ circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
+ skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
+ skb_reset_transport_header(skb);
+
+ return nr_rx_ip(skb, dev);
+ }
+
+ /*
+ * Find an existing socket connection, based on circuit ID, if it's
+ * a Connect Request base it on their circuit ID.
+ *
+ * Circuit ID 0/0 is not valid but it could still be a "reset" for a
+ * circuit that no longer exists at the other end ...
+ */
+
+ sk = NULL;
+
+ if (circuit_index == 0 && circuit_id == 0) {
+ if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
+ sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
+ } else {
+ if (frametype == NR_CONNREQ)
+ sk = nr_find_peer(circuit_index, circuit_id, src);
+ else
+ sk = nr_find_socket(circuit_index, circuit_id);
+ }
+
+ if (sk != NULL) {
+ bh_lock_sock(sk);
+ skb_reset_transport_header(skb);
+
+ if (frametype == NR_CONNACK && skb->len == 22)
+ nr_sk(sk)->bpqext = 1;
+ else
+ nr_sk(sk)->bpqext = 0;
+
+ ret = nr_process_rx_frame(sk, skb);
+ bh_unlock_sock(sk);
+ sock_put(sk);
+ return ret;
+ }
+
+ /*
+ * Now it should be a CONNREQ.
+ */
+ if (frametype != NR_CONNREQ) {
+ /*
+ * Here it would be nice to be able to send a reset but
+ * NET/ROM doesn't have one. We've tried to extend the protocol
+ * by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
+ * apparently kills BPQ boxes... :-(
+ * So now we try to follow the established behaviour of
+ * G8PZT's Xrouter which is sending packets with command type 7
+ * as an extension of the protocol.
+ */
+ if (sysctl_netrom_reset_circuit &&
+ (frametype != NR_RESET || flags != 0))
+ nr_transmit_reset(skb, 1);
+
+ return 0;
+ }
+
+ sk = nr_find_listener(dest);
+
+ user = (ax25_address *)(skb->data + 21);
+
+ if (sk == NULL || sk_acceptq_is_full(sk) ||
+ (make = nr_make_new(sk)) == NULL) {
+ nr_transmit_refusal(skb, 0);
+ if (sk)
+ sock_put(sk);
+ return 0;
+ }
+
+ bh_lock_sock(sk);
+
+ window = skb->data[20];
+
+ sock_hold(make);
+ skb->sk = make;
+ skb->destructor = sock_efree;
+ make->sk_state = TCP_ESTABLISHED;
+
+ /* Fill in his circuit details */
+ nr_make = nr_sk(make);
+ nr_make->source_addr = *dest;
+ nr_make->dest_addr = *src;
+ nr_make->user_addr = *user;
+
+ nr_make->your_index = circuit_index;
+ nr_make->your_id = circuit_id;
+
+ bh_unlock_sock(sk);
+ circuit = nr_find_next_circuit();
+ bh_lock_sock(sk);
+
+ nr_make->my_index = circuit / 256;
+ nr_make->my_id = circuit % 256;
+
+ circuit++;
+
+ /* Window negotiation */
+ if (window < nr_make->window)
+ nr_make->window = window;
+
+ /* L4 timeout negotiation */
+ if (skb->len == 37) {
+ timeout = skb->data[36] * 256 + skb->data[35];
+ if (timeout * HZ < nr_make->t1)
+ nr_make->t1 = timeout * HZ;
+ nr_make->bpqext = 1;
+ } else {
+ nr_make->bpqext = 0;
+ }
+
+ nr_write_internal(make, NR_CONNACK);
+
+ nr_make->condition = 0x00;
+ nr_make->vs = 0;
+ nr_make->va = 0;
+ nr_make->vr = 0;
+ nr_make->vl = 0;
+ nr_make->state = NR_STATE_3;
+ sk_acceptq_added(sk);
+ skb_queue_head(&sk->sk_receive_queue, skb);
+
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_data_ready(sk);
+
+ bh_unlock_sock(sk);
+ sock_put(sk);
+
+ nr_insert_socket(make);
+
+ nr_start_heartbeat(make);
+ nr_start_idletimer(make);
+
+ return 1;
+}
+
+static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+ struct sock *sk = sock->sk;
+ struct nr_sock *nr = nr_sk(sk);
+ DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
+ int err;
+ struct sockaddr_ax25 sax;
+ struct sk_buff *skb;
+ unsigned char *asmptr;
+ int size;
+
+ if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
+ return -EINVAL;
+
+ lock_sock(sk);
+ if (sock_flag(sk, SOCK_ZAPPED)) {
+ err = -EADDRNOTAVAIL;
+ goto out;
+ }
+
+ if (sk->sk_shutdown & SEND_SHUTDOWN) {
+ send_sig(SIGPIPE, current, 0);
+ err = -EPIPE;
+ goto out;
+ }
+
+ if (nr->device == NULL) {
+ err = -ENETUNREACH;
+ goto out;
+ }
+
+ if (usax) {
+ if (msg->msg_namelen < sizeof(sax)) {
+ err = -EINVAL;
+ goto out;
+ }
+ sax = *usax;
+ if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
+ err = -EISCONN;
+ goto out;
+ }
+ if (sax.sax25_family != AF_NETROM) {
+ err = -EINVAL;
+ goto out;
+ }
+ } else {
+ if (sk->sk_state != TCP_ESTABLISHED) {
+ err = -ENOTCONN;
+ goto out;
+ }
+ sax.sax25_family = AF_NETROM;
+ sax.sax25_call = nr->dest_addr;
+ }
+
+ /* Build a packet - the conventional user limit is 236 bytes. We can
+ do ludicrously large NetROM frames but must not overflow */
+ if (len > 65536) {
+ err = -EMSGSIZE;
+ goto out;
+ }
+
+ size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
+
+ if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
+ goto out;
+
+ skb_reserve(skb, size - len);
+ skb_reset_transport_header(skb);
+
+ /*
+ * Push down the NET/ROM header
+ */
+
+ asmptr = skb_push(skb, NR_TRANSPORT_LEN);
+
+ /* Build a NET/ROM Transport header */
+
+ *asmptr++ = nr->your_index;
+ *asmptr++ = nr->your_id;
+ *asmptr++ = 0; /* To be filled in later */
+ *asmptr++ = 0; /* Ditto */
+ *asmptr++ = NR_INFO;
+
+ /*
+ * Put the data on the end
+ */
+ skb_put(skb, len);
+
+ /* User data follows immediately after the NET/ROM transport header */
+ if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
+ kfree_skb(skb);
+ err = -EFAULT;
+ goto out;
+ }
+
+ if (sk->sk_state != TCP_ESTABLISHED) {
+ kfree_skb(skb);
+ err = -ENOTCONN;
+ goto out;
+ }
+
+ nr_output(sk, skb); /* Shove it onto the queue */
+
+ err = len;
+out:
+ release_sock(sk);
+ return err;
+}
+
+static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
+ int flags)
+{
+ struct sock *sk = sock->sk;
+ DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
+ size_t copied;
+ struct sk_buff *skb;
+ int er;
+
+ /*
+ * This works for seqpacket too. The receiver has ordered the queue for
+ * us! We do one quick check first though
+ */
+
+ lock_sock(sk);
+ if (sk->sk_state != TCP_ESTABLISHED) {
+ release_sock(sk);
+ return -ENOTCONN;
+ }
+
+ /* Now we can treat all alike */
+ skb = skb_recv_datagram(sk, flags, &er);
+ if (!skb) {
+ release_sock(sk);
+ return er;
+ }
+
+ skb_reset_transport_header(skb);
+ copied = skb->len;
+
+ if (copied > size) {
+ copied = size;
+ msg->msg_flags |= MSG_TRUNC;
+ }
+
+ er = skb_copy_datagram_msg(skb, 0, msg, copied);
+ if (er < 0) {
+ skb_free_datagram(sk, skb);
+ release_sock(sk);
+ return er;
+ }
+
+ if (sax != NULL) {
+ memset(sax, 0, sizeof(*sax));
+ sax->sax25_family = AF_NETROM;
+ skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
+ AX25_ADDR_LEN);
+ msg->msg_namelen = sizeof(*sax);
+ }
+
+ skb_free_datagram(sk, skb);
+
+ release_sock(sk);
+ return copied;
+}
+
+
+static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+ void __user *argp = (void __user *)arg;
+
+ switch (cmd) {
+ case TIOCOUTQ: {
+ long amount;
+
+ lock_sock(sk);
+ amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
+ if (amount < 0)
+ amount = 0;
+ release_sock(sk);
+ return put_user(amount, (int __user *)argp);
+ }
+
+ case TIOCINQ: {
+ struct sk_buff *skb;
+ long amount = 0L;
+
+ lock_sock(sk);
+ /* These two are safe on a single CPU system as only user tasks fiddle here */
+ if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
+ amount = skb->len;
+ release_sock(sk);
+ return put_user(amount, (int __user *)argp);
+ }
+
+ case SIOCGIFADDR:
+ case SIOCSIFADDR:
+ case SIOCGIFDSTADDR:
+ case SIOCSIFDSTADDR:
+ case SIOCGIFBRDADDR:
+ case SIOCSIFBRDADDR:
+ case SIOCGIFNETMASK:
+ case SIOCSIFNETMASK:
+ case SIOCGIFMETRIC:
+ case SIOCSIFMETRIC:
+ return -EINVAL;
+
+ case SIOCADDRT:
+ case SIOCDELRT:
+ case SIOCNRDECOBS:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ return nr_rt_ioctl(cmd, argp);
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PROC_FS
+
+static void *nr_info_start(struct seq_file *seq, loff_t *pos)
+ __acquires(&nr_list_lock)
+{
+ spin_lock_bh(&nr_list_lock);
+ return seq_hlist_start_head(&nr_list, *pos);
+}
+
+static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ return seq_hlist_next(v, &nr_list, pos);
+}
+
+static void nr_info_stop(struct seq_file *seq, void *v)
+ __releases(&nr_list_lock)
+{
+ spin_unlock_bh(&nr_list_lock);
+}
+
+static int nr_info_show(struct seq_file *seq, void *v)
+{
+ struct sock *s = sk_entry(v);
+ struct net_device *dev;
+ struct nr_sock *nr;
+ const char *devname;
+ char buf[11];
+
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq,
+"user_addr dest_node src_node dev my your st vs vr va t1 t2 t4 idle n2 wnd Snd-Q Rcv-Q inode\n");
+
+ else {
+
+ bh_lock_sock(s);
+ nr = nr_sk(s);
+
+ if ((dev = nr->device) == NULL)
+ devname = "???";
+ else
+ devname = dev->name;
+
+ seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
+ seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
+ seq_printf(seq,
+"%-9s %-3s %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
+ ax2asc(buf, &nr->source_addr),
+ devname,
+ nr->my_index,
+ nr->my_id,
+ nr->your_index,
+ nr->your_id,
+ nr->state,
+ nr->vs,
+ nr->vr,
+ nr->va,
+ ax25_display_timer(&nr->t1timer) / HZ,
+ nr->t1 / HZ,
+ ax25_display_timer(&nr->t2timer) / HZ,
+ nr->t2 / HZ,
+ ax25_display_timer(&nr->t4timer) / HZ,
+ nr->t4 / HZ,
+ ax25_display_timer(&nr->idletimer) / (60 * HZ),
+ nr->idle / (60 * HZ),
+ nr->n2count,
+ nr->n2,
+ nr->window,
+ sk_wmem_alloc_get(s),
+ sk_rmem_alloc_get(s),
+ s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
+
+ bh_unlock_sock(s);
+ }
+ return 0;
+}
+
+static const struct seq_operations nr_info_seqops = {
+ .start = nr_info_start,
+ .next = nr_info_next,
+ .stop = nr_info_stop,
+ .show = nr_info_show,
+};
+#endif /* CONFIG_PROC_FS */
+
+static const struct net_proto_family nr_family_ops = {
+ .family = PF_NETROM,
+ .create = nr_create,
+ .owner = THIS_MODULE,
+};
+
+static const struct proto_ops nr_proto_ops = {
+ .family = PF_NETROM,
+ .owner = THIS_MODULE,
+ .release = nr_release,
+ .bind = nr_bind,
+ .connect = nr_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = nr_accept,
+ .getname = nr_getname,
+ .poll = datagram_poll,
+ .ioctl = nr_ioctl,
+ .gettstamp = sock_gettstamp,
+ .listen = nr_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = nr_setsockopt,
+ .getsockopt = nr_getsockopt,
+ .sendmsg = nr_sendmsg,
+ .recvmsg = nr_recvmsg,
+ .mmap = sock_no_mmap,
+};
+
+static struct notifier_block nr_dev_notifier = {
+ .notifier_call = nr_device_event,
+};
+
+static struct net_device **dev_nr;
+
+static struct ax25_protocol nr_pid = {
+ .pid = AX25_P_NETROM,
+ .func = nr_route_frame
+};
+
+static struct ax25_linkfail nr_linkfail_notifier = {
+ .func = nr_link_failed,
+};
+
+static int __init nr_proto_init(void)
+{
+ int i;
+ int rc = proto_register(&nr_proto, 0);
+
+ if (rc)
+ return rc;
+
+ if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
+ pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
+ __func__);
+ rc = -EINVAL;
+ goto unregister_proto;
+ }
+
+ dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
+ if (!dev_nr) {
+ pr_err("NET/ROM: %s - unable to allocate device array\n",
+ __func__);
+ rc = -ENOMEM;
+ goto unregister_proto;
+ }
+
+ for (i = 0; i < nr_ndevs; i++) {
+ char name[IFNAMSIZ];
+ struct net_device *dev;
+
+ sprintf(name, "nr%d", i);
+ dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
+ if (!dev) {
+ rc = -ENOMEM;
+ goto fail;
+ }
+
+ dev->base_addr = i;
+ rc = register_netdev(dev);
+ if (rc) {
+ free_netdev(dev);
+ goto fail;
+ }
+ nr_set_lockdep_key(dev);
+ dev_nr[i] = dev;
+ }
+
+ rc = sock_register(&nr_family_ops);
+ if (rc)
+ goto fail;
+
+ rc = register_netdevice_notifier(&nr_dev_notifier);
+ if (rc)
+ goto out_sock;
+
+ ax25_register_pid(&nr_pid);
+ ax25_linkfail_register(&nr_linkfail_notifier);
+
+#ifdef CONFIG_SYSCTL
+ rc = nr_register_sysctl();
+ if (rc)
+ goto out_sysctl;
+#endif
+
+ nr_loopback_init();
+
+ rc = -ENOMEM;
+ if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
+ goto proc_remove1;
+ if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
+ &nr_neigh_seqops))
+ goto proc_remove2;
+ if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
+ &nr_node_seqops))
+ goto proc_remove3;
+
+ return 0;
+
+proc_remove3:
+ remove_proc_entry("nr_neigh", init_net.proc_net);
+proc_remove2:
+ remove_proc_entry("nr", init_net.proc_net);
+proc_remove1:
+
+ nr_loopback_clear();
+ nr_rt_free();
+
+#ifdef CONFIG_SYSCTL
+ nr_unregister_sysctl();
+out_sysctl:
+#endif
+ ax25_linkfail_release(&nr_linkfail_notifier);
+ ax25_protocol_release(AX25_P_NETROM);
+ unregister_netdevice_notifier(&nr_dev_notifier);
+out_sock:
+ sock_unregister(PF_NETROM);
+fail:
+ while (--i >= 0) {
+ unregister_netdev(dev_nr[i]);
+ free_netdev(dev_nr[i]);
+ }
+ kfree(dev_nr);
+unregister_proto:
+ proto_unregister(&nr_proto);
+ return rc;
+}
+
+module_init(nr_proto_init);
+
+module_param(nr_ndevs, int, 0);
+MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
+
+MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
+MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_NETROM);
+
+static void __exit nr_exit(void)
+{
+ int i;
+
+ remove_proc_entry("nr", init_net.proc_net);
+ remove_proc_entry("nr_neigh", init_net.proc_net);
+ remove_proc_entry("nr_nodes", init_net.proc_net);
+ nr_loopback_clear();
+
+ nr_rt_free();
+
+#ifdef CONFIG_SYSCTL
+ nr_unregister_sysctl();
+#endif
+
+ ax25_linkfail_release(&nr_linkfail_notifier);
+ ax25_protocol_release(AX25_P_NETROM);
+
+ unregister_netdevice_notifier(&nr_dev_notifier);
+
+ sock_unregister(PF_NETROM);
+
+ for (i = 0; i < nr_ndevs; i++) {
+ struct net_device *dev = dev_nr[i];
+ if (dev) {
+ unregister_netdev(dev);
+ free_netdev(dev);
+ }
+ }
+
+ kfree(dev_nr);
+ proto_unregister(&nr_proto);
+}
+module_exit(nr_exit);