diff options
Diffstat (limited to 'net/netrom/af_netrom.c')
| -rw-r--r-- | net/netrom/af_netrom.c | 1537 |
1 files changed, 1537 insertions, 0 deletions
diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c new file mode 100644 index 000000000..ec5747969 --- /dev/null +++ b/net/netrom/af_netrom.c @@ -0,0 +1,1537 @@ +// 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, + .sendpage = sock_no_sendpage, +}; + +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); |