diff options
Diffstat (limited to '')
| -rw-r--r-- | net/netrom/Makefile | 10 | ||||
| -rw-r--r-- | net/netrom/af_netrom.c | 1536 | ||||
| -rw-r--r-- | net/netrom/nr_dev.c | 178 | ||||
| -rw-r--r-- | net/netrom/nr_in.c | 302 | ||||
| -rw-r--r-- | net/netrom/nr_loopback.c | 74 | ||||
| -rw-r--r-- | net/netrom/nr_out.c | 270 | ||||
| -rw-r--r-- | net/netrom/nr_route.c | 980 | ||||
| -rw-r--r-- | net/netrom/nr_subr.c | 279 | ||||
| -rw-r--r-- | net/netrom/nr_timer.c | 248 | ||||
| -rw-r--r-- | net/netrom/sysctl_net_netrom.c | 157 |
10 files changed, 4034 insertions, 0 deletions
diff --git a/net/netrom/Makefile b/net/netrom/Makefile new file mode 100644 index 000000000..603e36c9a --- /dev/null +++ b/net/netrom/Makefile @@ -0,0 +1,10 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Makefile for the Linux NET/ROM layer. +# + +obj-$(CONFIG_NETROM) += netrom.o + +netrom-y := af_netrom.o nr_dev.o nr_in.o nr_loopback.o \ + nr_out.o nr_route.o nr_subr.o nr_timer.o +netrom-$(CONFIG_SYSCTL) += sysctl_net_netrom.o diff --git a/net/netrom/af_netrom.c b/net/netrom/af_netrom.c new file mode 100644 index 000000000..247471631 --- /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; + 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 = (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 */ + if ((skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &er)) == NULL) { + 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); diff --git a/net/netrom/nr_dev.c b/net/netrom/nr_dev.c new file mode 100644 index 000000000..29e418c8c --- /dev/null +++ b/net/netrom/nr_dev.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + */ +#include <linux/module.h> +#include <linux/proc_fs.h> +#include <linux/kernel.h> +#include <linux/interrupt.h> +#include <linux/fs.h> +#include <linux/types.h> +#include <linux/sysctl.h> +#include <linux/string.h> +#include <linux/socket.h> +#include <linux/errno.h> +#include <linux/fcntl.h> +#include <linux/in.h> +#include <linux/if_ether.h> /* For the statistics structure. */ +#include <linux/slab.h> +#include <linux/uaccess.h> + +#include <asm/io.h> + +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> + +#include <net/ip.h> +#include <net/arp.h> + +#include <net/ax25.h> +#include <net/netrom.h> + +/* + * Only allow IP over NET/ROM frames through if the netrom device is up. + */ + +int nr_rx_ip(struct sk_buff *skb, struct net_device *dev) +{ + struct net_device_stats *stats = &dev->stats; + + if (!netif_running(dev)) { + stats->rx_dropped++; + return 0; + } + + stats->rx_packets++; + stats->rx_bytes += skb->len; + + skb->protocol = htons(ETH_P_IP); + + /* Spoof incoming device */ + skb->dev = dev; + skb->mac_header = skb->network_header; + skb_reset_network_header(skb); + skb->pkt_type = PACKET_HOST; + + netif_rx(skb); + + return 1; +} + +static int nr_header(struct sk_buff *skb, struct net_device *dev, + unsigned short type, + const void *daddr, const void *saddr, unsigned int len) +{ + unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN); + + memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len); + buff[6] &= ~AX25_CBIT; + buff[6] &= ~AX25_EBIT; + buff[6] |= AX25_SSSID_SPARE; + buff += AX25_ADDR_LEN; + + if (daddr != NULL) + memcpy(buff, daddr, dev->addr_len); + buff[6] &= ~AX25_CBIT; + buff[6] |= AX25_EBIT; + buff[6] |= AX25_SSSID_SPARE; + buff += AX25_ADDR_LEN; + + *buff++ = sysctl_netrom_network_ttl_initialiser; + + *buff++ = NR_PROTO_IP; + *buff++ = NR_PROTO_IP; + *buff++ = 0; + *buff++ = 0; + *buff++ = NR_PROTOEXT; + + if (daddr != NULL) + return 37; + + return -37; +} + +static int __must_check nr_set_mac_address(struct net_device *dev, void *addr) +{ + struct sockaddr *sa = addr; + int err; + + if (!memcmp(dev->dev_addr, sa->sa_data, dev->addr_len)) + return 0; + + if (dev->flags & IFF_UP) { + err = ax25_listen_register((ax25_address *)sa->sa_data, NULL); + if (err) + return err; + + ax25_listen_release((ax25_address *)dev->dev_addr, NULL); + } + + memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); + + return 0; +} + +static int nr_open(struct net_device *dev) +{ + int err; + + err = ax25_listen_register((ax25_address *)dev->dev_addr, NULL); + if (err) + return err; + + netif_start_queue(dev); + + return 0; +} + +static int nr_close(struct net_device *dev) +{ + ax25_listen_release((ax25_address *)dev->dev_addr, NULL); + netif_stop_queue(dev); + return 0; +} + +static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct net_device_stats *stats = &dev->stats; + unsigned int len = skb->len; + + if (!nr_route_frame(skb, NULL)) { + kfree_skb(skb); + stats->tx_errors++; + return NETDEV_TX_OK; + } + + stats->tx_packets++; + stats->tx_bytes += len; + + return NETDEV_TX_OK; +} + +static const struct header_ops nr_header_ops = { + .create = nr_header, +}; + +static const struct net_device_ops nr_netdev_ops = { + .ndo_open = nr_open, + .ndo_stop = nr_close, + .ndo_start_xmit = nr_xmit, + .ndo_set_mac_address = nr_set_mac_address, +}; + +void nr_setup(struct net_device *dev) +{ + dev->mtu = NR_MAX_PACKET_SIZE; + dev->netdev_ops = &nr_netdev_ops; + dev->header_ops = &nr_header_ops; + dev->hard_header_len = NR_NETWORK_LEN + NR_TRANSPORT_LEN; + dev->addr_len = AX25_ADDR_LEN; + dev->type = ARPHRD_NETROM; + + /* New-style flags. */ + dev->flags = IFF_NOARP; +} diff --git a/net/netrom/nr_in.c b/net/netrom/nr_in.c new file mode 100644 index 000000000..69e58906c --- /dev/null +++ b/net/netrom/nr_in.c @@ -0,0 +1,302 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/netrom.h> + +static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more) +{ + struct sk_buff *skbo, *skbn = skb; + struct nr_sock *nr = nr_sk(sk); + + skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN); + + nr_start_idletimer(sk); + + if (more) { + nr->fraglen += skb->len; + skb_queue_tail(&nr->frag_queue, skb); + return 0; + } + + if (!more && nr->fraglen > 0) { /* End of fragment */ + nr->fraglen += skb->len; + skb_queue_tail(&nr->frag_queue, skb); + + if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL) + return 1; + + skb_reset_transport_header(skbn); + + while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) { + skb_copy_from_linear_data(skbo, + skb_put(skbn, skbo->len), + skbo->len); + kfree_skb(skbo); + } + + nr->fraglen = 0; + } + + return sock_queue_rcv_skb(sk, skbn); +} + +/* + * State machine for state 1, Awaiting Connection State. + * The handling of the timer(s) is in file nr_timer.c. + * Handling of state 0 and connection release is in netrom.c. + */ +static int nr_state1_machine(struct sock *sk, struct sk_buff *skb, + int frametype) +{ + switch (frametype) { + case NR_CONNACK: { + struct nr_sock *nr = nr_sk(sk); + + nr_stop_t1timer(sk); + nr_start_idletimer(sk); + nr->your_index = skb->data[17]; + nr->your_id = skb->data[18]; + nr->vs = 0; + nr->va = 0; + nr->vr = 0; + nr->vl = 0; + nr->state = NR_STATE_3; + nr->n2count = 0; + nr->window = skb->data[20]; + sk->sk_state = TCP_ESTABLISHED; + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + break; + } + + case NR_CONNACK | NR_CHOKE_FLAG: + nr_disconnect(sk, ECONNREFUSED); + break; + + case NR_RESET: + if (sysctl_netrom_reset_circuit) + nr_disconnect(sk, ECONNRESET); + break; + + default: + break; + } + return 0; +} + +/* + * State machine for state 2, Awaiting Release State. + * The handling of the timer(s) is in file nr_timer.c + * Handling of state 0 and connection release is in netrom.c. + */ +static int nr_state2_machine(struct sock *sk, struct sk_buff *skb, + int frametype) +{ + switch (frametype) { + case NR_CONNACK | NR_CHOKE_FLAG: + nr_disconnect(sk, ECONNRESET); + break; + + case NR_DISCREQ: + nr_write_internal(sk, NR_DISCACK); + fallthrough; + case NR_DISCACK: + nr_disconnect(sk, 0); + break; + + case NR_RESET: + if (sysctl_netrom_reset_circuit) + nr_disconnect(sk, ECONNRESET); + break; + + default: + break; + } + return 0; +} + +/* + * State machine for state 3, Connected State. + * The handling of the timer(s) is in file nr_timer.c + * Handling of state 0 and connection release is in netrom.c. + */ +static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct nr_sock *nrom = nr_sk(sk); + struct sk_buff_head temp_queue; + struct sk_buff *skbn; + unsigned short save_vr; + unsigned short nr, ns; + int queued = 0; + + nr = skb->data[18]; + ns = skb->data[17]; + + switch (frametype) { + case NR_CONNREQ: + nr_write_internal(sk, NR_CONNACK); + break; + + case NR_DISCREQ: + nr_write_internal(sk, NR_DISCACK); + nr_disconnect(sk, 0); + break; + + case NR_CONNACK | NR_CHOKE_FLAG: + case NR_DISCACK: + nr_disconnect(sk, ECONNRESET); + break; + + case NR_INFOACK: + case NR_INFOACK | NR_CHOKE_FLAG: + case NR_INFOACK | NR_NAK_FLAG: + case NR_INFOACK | NR_NAK_FLAG | NR_CHOKE_FLAG: + if (frametype & NR_CHOKE_FLAG) { + nrom->condition |= NR_COND_PEER_RX_BUSY; + nr_start_t4timer(sk); + } else { + nrom->condition &= ~NR_COND_PEER_RX_BUSY; + nr_stop_t4timer(sk); + } + if (!nr_validate_nr(sk, nr)) { + break; + } + if (frametype & NR_NAK_FLAG) { + nr_frames_acked(sk, nr); + nr_send_nak_frame(sk); + } else { + if (nrom->condition & NR_COND_PEER_RX_BUSY) { + nr_frames_acked(sk, nr); + } else { + nr_check_iframes_acked(sk, nr); + } + } + break; + + case NR_INFO: + case NR_INFO | NR_NAK_FLAG: + case NR_INFO | NR_CHOKE_FLAG: + case NR_INFO | NR_MORE_FLAG: + case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG: + case NR_INFO | NR_CHOKE_FLAG | NR_MORE_FLAG: + case NR_INFO | NR_NAK_FLAG | NR_MORE_FLAG: + case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG | NR_MORE_FLAG: + if (frametype & NR_CHOKE_FLAG) { + nrom->condition |= NR_COND_PEER_RX_BUSY; + nr_start_t4timer(sk); + } else { + nrom->condition &= ~NR_COND_PEER_RX_BUSY; + nr_stop_t4timer(sk); + } + if (nr_validate_nr(sk, nr)) { + if (frametype & NR_NAK_FLAG) { + nr_frames_acked(sk, nr); + nr_send_nak_frame(sk); + } else { + if (nrom->condition & NR_COND_PEER_RX_BUSY) { + nr_frames_acked(sk, nr); + } else { + nr_check_iframes_acked(sk, nr); + } + } + } + queued = 1; + skb_queue_head(&nrom->reseq_queue, skb); + if (nrom->condition & NR_COND_OWN_RX_BUSY) + break; + skb_queue_head_init(&temp_queue); + do { + save_vr = nrom->vr; + while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) { + ns = skbn->data[17]; + if (ns == nrom->vr) { + if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) { + nrom->vr = (nrom->vr + 1) % NR_MODULUS; + } else { + nrom->condition |= NR_COND_OWN_RX_BUSY; + skb_queue_tail(&temp_queue, skbn); + } + } else if (nr_in_rx_window(sk, ns)) { + skb_queue_tail(&temp_queue, skbn); + } else { + kfree_skb(skbn); + } + } + while ((skbn = skb_dequeue(&temp_queue)) != NULL) { + skb_queue_tail(&nrom->reseq_queue, skbn); + } + } while (save_vr != nrom->vr); + /* + * Window is full, ack it immediately. + */ + if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) { + nr_enquiry_response(sk); + } else { + if (!(nrom->condition & NR_COND_ACK_PENDING)) { + nrom->condition |= NR_COND_ACK_PENDING; + nr_start_t2timer(sk); + } + } + break; + + case NR_RESET: + if (sysctl_netrom_reset_circuit) + nr_disconnect(sk, ECONNRESET); + break; + + default: + break; + } + return queued; +} + +/* Higher level upcall for a LAPB frame - called with sk locked */ +int nr_process_rx_frame(struct sock *sk, struct sk_buff *skb) +{ + struct nr_sock *nr = nr_sk(sk); + int queued = 0, frametype; + + if (nr->state == NR_STATE_0) + return 0; + + frametype = skb->data[19]; + + switch (nr->state) { + case NR_STATE_1: + queued = nr_state1_machine(sk, skb, frametype); + break; + case NR_STATE_2: + queued = nr_state2_machine(sk, skb, frametype); + break; + case NR_STATE_3: + queued = nr_state3_machine(sk, skb, frametype); + break; + } + + nr_kick(sk); + + return queued; +} diff --git a/net/netrom/nr_loopback.c b/net/netrom/nr_loopback.c new file mode 100644 index 000000000..a880dd33e --- /dev/null +++ b/net/netrom/nr_loopback.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi) + */ +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/socket.h> +#include <linux/timer.h> +#include <net/ax25.h> +#include <linux/skbuff.h> +#include <net/netrom.h> +#include <linux/init.h> + +static void nr_loopback_timer(struct timer_list *); + +static struct sk_buff_head loopback_queue; +static DEFINE_TIMER(loopback_timer, nr_loopback_timer); + +void __init nr_loopback_init(void) +{ + skb_queue_head_init(&loopback_queue); +} + +static inline int nr_loopback_running(void) +{ + return timer_pending(&loopback_timer); +} + +int nr_loopback_queue(struct sk_buff *skb) +{ + struct sk_buff *skbn; + + if ((skbn = alloc_skb(skb->len, GFP_ATOMIC)) != NULL) { + skb_copy_from_linear_data(skb, skb_put(skbn, skb->len), skb->len); + skb_reset_transport_header(skbn); + + skb_queue_tail(&loopback_queue, skbn); + + if (!nr_loopback_running()) + mod_timer(&loopback_timer, jiffies + 10); + } + + kfree_skb(skb); + return 1; +} + +static void nr_loopback_timer(struct timer_list *unused) +{ + struct sk_buff *skb; + ax25_address *nr_dest; + struct net_device *dev; + + if ((skb = skb_dequeue(&loopback_queue)) != NULL) { + nr_dest = (ax25_address *)(skb->data + 7); + + dev = nr_dev_get(nr_dest); + + if (dev == NULL || nr_rx_frame(skb, dev) == 0) + kfree_skb(skb); + + if (dev != NULL) + dev_put(dev); + + if (!skb_queue_empty(&loopback_queue) && !nr_loopback_running()) + mod_timer(&loopback_timer, jiffies + 10); + } +} + +void nr_loopback_clear(void) +{ + del_timer_sync(&loopback_timer); + skb_queue_purge(&loopback_queue); +} diff --git a/net/netrom/nr_out.c b/net/netrom/nr_out.c new file mode 100644 index 000000000..44929657f --- /dev/null +++ b/net/netrom/nr_out.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/netrom.h> + +/* + * This is where all NET/ROM frames pass, except for IP-over-NET/ROM which + * cannot be fragmented in this manner. + */ +void nr_output(struct sock *sk, struct sk_buff *skb) +{ + struct sk_buff *skbn; + unsigned char transport[NR_TRANSPORT_LEN]; + int err, frontlen, len; + + if (skb->len - NR_TRANSPORT_LEN > NR_MAX_PACKET_SIZE) { + /* Save a copy of the Transport Header */ + skb_copy_from_linear_data(skb, transport, NR_TRANSPORT_LEN); + skb_pull(skb, NR_TRANSPORT_LEN); + + frontlen = skb_headroom(skb); + + while (skb->len > 0) { + if ((skbn = sock_alloc_send_skb(sk, frontlen + NR_MAX_PACKET_SIZE, 0, &err)) == NULL) + return; + + skb_reserve(skbn, frontlen); + + len = (NR_MAX_PACKET_SIZE > skb->len) ? skb->len : NR_MAX_PACKET_SIZE; + + /* Copy the user data */ + skb_copy_from_linear_data(skb, skb_put(skbn, len), len); + skb_pull(skb, len); + + /* Duplicate the Transport Header */ + skb_push(skbn, NR_TRANSPORT_LEN); + skb_copy_to_linear_data(skbn, transport, + NR_TRANSPORT_LEN); + if (skb->len > 0) + skbn->data[4] |= NR_MORE_FLAG; + + skb_queue_tail(&sk->sk_write_queue, skbn); /* Throw it on the queue */ + } + + kfree_skb(skb); + } else { + skb_queue_tail(&sk->sk_write_queue, skb); /* Throw it on the queue */ + } + + nr_kick(sk); +} + +/* + * This procedure is passed a buffer descriptor for an iframe. It builds + * the rest of the control part of the frame and then writes it out. + */ +static void nr_send_iframe(struct sock *sk, struct sk_buff *skb) +{ + struct nr_sock *nr = nr_sk(sk); + + if (skb == NULL) + return; + + skb->data[2] = nr->vs; + skb->data[3] = nr->vr; + + if (nr->condition & NR_COND_OWN_RX_BUSY) + skb->data[4] |= NR_CHOKE_FLAG; + + nr_start_idletimer(sk); + + nr_transmit_buffer(sk, skb); +} + +void nr_send_nak_frame(struct sock *sk) +{ + struct sk_buff *skb, *skbn; + struct nr_sock *nr = nr_sk(sk); + + if ((skb = skb_peek(&nr->ack_queue)) == NULL) + return; + + if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) + return; + + skbn->data[2] = nr->va; + skbn->data[3] = nr->vr; + + if (nr->condition & NR_COND_OWN_RX_BUSY) + skbn->data[4] |= NR_CHOKE_FLAG; + + nr_transmit_buffer(sk, skbn); + + nr->condition &= ~NR_COND_ACK_PENDING; + nr->vl = nr->vr; + + nr_stop_t1timer(sk); +} + +void nr_kick(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + struct sk_buff *skb, *skbn; + unsigned short start, end; + + if (nr->state != NR_STATE_3) + return; + + if (nr->condition & NR_COND_PEER_RX_BUSY) + return; + + if (!skb_peek(&sk->sk_write_queue)) + return; + + start = (skb_peek(&nr->ack_queue) == NULL) ? nr->va : nr->vs; + end = (nr->va + nr->window) % NR_MODULUS; + + if (start == end) + return; + + nr->vs = start; + + /* + * Transmit data until either we're out of data to send or + * the window is full. + */ + + /* + * Dequeue the frame and copy it. + */ + skb = skb_dequeue(&sk->sk_write_queue); + + do { + if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) { + skb_queue_head(&sk->sk_write_queue, skb); + break; + } + + skb_set_owner_w(skbn, sk); + + /* + * Transmit the frame copy. + */ + nr_send_iframe(sk, skbn); + + nr->vs = (nr->vs + 1) % NR_MODULUS; + + /* + * Requeue the original data frame. + */ + skb_queue_tail(&nr->ack_queue, skb); + + } while (nr->vs != end && + (skb = skb_dequeue(&sk->sk_write_queue)) != NULL); + + nr->vl = nr->vr; + nr->condition &= ~NR_COND_ACK_PENDING; + + if (!nr_t1timer_running(sk)) + nr_start_t1timer(sk); +} + +void nr_transmit_buffer(struct sock *sk, struct sk_buff *skb) +{ + struct nr_sock *nr = nr_sk(sk); + unsigned char *dptr; + + /* + * Add the protocol byte and network header. + */ + dptr = skb_push(skb, NR_NETWORK_LEN); + + memcpy(dptr, &nr->source_addr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] &= ~AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + + memcpy(dptr, &nr->dest_addr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] |= AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + + *dptr++ = sysctl_netrom_network_ttl_initialiser; + + if (!nr_route_frame(skb, NULL)) { + kfree_skb(skb); + nr_disconnect(sk, ENETUNREACH); + } +} + +/* + * The following routines are taken from page 170 of the 7th ARRL Computer + * Networking Conference paper, as is the whole state machine. + */ + +void nr_establish_data_link(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + nr->condition = 0x00; + nr->n2count = 0; + + nr_write_internal(sk, NR_CONNREQ); + + nr_stop_t2timer(sk); + nr_stop_t4timer(sk); + nr_stop_idletimer(sk); + nr_start_t1timer(sk); +} + +/* + * Never send a NAK when we are CHOKEd. + */ +void nr_enquiry_response(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + int frametype = NR_INFOACK; + + if (nr->condition & NR_COND_OWN_RX_BUSY) { + frametype |= NR_CHOKE_FLAG; + } else { + if (skb_peek(&nr->reseq_queue) != NULL) + frametype |= NR_NAK_FLAG; + } + + nr_write_internal(sk, frametype); + + nr->vl = nr->vr; + nr->condition &= ~NR_COND_ACK_PENDING; +} + +void nr_check_iframes_acked(struct sock *sk, unsigned short nr) +{ + struct nr_sock *nrom = nr_sk(sk); + + if (nrom->vs == nr) { + nr_frames_acked(sk, nr); + nr_stop_t1timer(sk); + nrom->n2count = 0; + } else { + if (nrom->va != nr) { + nr_frames_acked(sk, nr); + nr_start_t1timer(sk); + } + } +} diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c new file mode 100644 index 000000000..78da5eab2 --- /dev/null +++ b/net/netrom/nr_route.c @@ -0,0 +1,980 @@ +// 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 Tomi Manninen OH2BNS (oh2bns@sral.fi) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <net/arp.h> +#include <linux/if_arp.h> +#include <linux/skbuff.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 <linux/init.h> +#include <linux/spinlock.h> +#include <net/netrom.h> +#include <linux/seq_file.h> +#include <linux/export.h> + +static unsigned int nr_neigh_no = 1; + +static HLIST_HEAD(nr_node_list); +static DEFINE_SPINLOCK(nr_node_list_lock); +static HLIST_HEAD(nr_neigh_list); +static DEFINE_SPINLOCK(nr_neigh_list_lock); + +static struct nr_node *nr_node_get(ax25_address *callsign) +{ + struct nr_node *found = NULL; + struct nr_node *nr_node; + + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each(nr_node, &nr_node_list) + if (ax25cmp(callsign, &nr_node->callsign) == 0) { + nr_node_hold(nr_node); + found = nr_node; + break; + } + spin_unlock_bh(&nr_node_list_lock); + return found; +} + +static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign, + struct net_device *dev) +{ + struct nr_neigh *found = NULL; + struct nr_neigh *nr_neigh; + + spin_lock_bh(&nr_neigh_list_lock); + nr_neigh_for_each(nr_neigh, &nr_neigh_list) + if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && + nr_neigh->dev == dev) { + nr_neigh_hold(nr_neigh); + found = nr_neigh; + break; + } + spin_unlock_bh(&nr_neigh_list_lock); + return found; +} + +static void nr_remove_neigh(struct nr_neigh *); + +/* re-sort the routes in quality order. */ +static void re_sort_routes(struct nr_node *nr_node, int x, int y) +{ + if (nr_node->routes[y].quality > nr_node->routes[x].quality) { + if (nr_node->which == x) + nr_node->which = y; + else if (nr_node->which == y) + nr_node->which = x; + + swap(nr_node->routes[x], nr_node->routes[y]); + } +} + +/* + * Add a new route to a node, and in the process add the node and the + * neighbour if it is new. + */ +static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic, + ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev, + int quality, int obs_count) +{ + struct nr_node *nr_node; + struct nr_neigh *nr_neigh; + int i, found; + struct net_device *odev; + + if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */ + dev_put(odev); + return -EINVAL; + } + + nr_node = nr_node_get(nr); + + nr_neigh = nr_neigh_get_dev(ax25, dev); + + /* + * The L2 link to a neighbour has failed in the past + * and now a frame comes from this neighbour. We assume + * it was a temporary trouble with the link and reset the + * routes now (and not wait for a node broadcast). + */ + if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) { + struct nr_node *nr_nodet; + + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each(nr_nodet, &nr_node_list) { + nr_node_lock(nr_nodet); + for (i = 0; i < nr_nodet->count; i++) + if (nr_nodet->routes[i].neighbour == nr_neigh) + if (i < nr_nodet->which) + nr_nodet->which = i; + nr_node_unlock(nr_nodet); + } + spin_unlock_bh(&nr_node_list_lock); + } + + if (nr_neigh != NULL) + nr_neigh->failed = 0; + + if (quality == 0 && nr_neigh != NULL && nr_node != NULL) { + nr_neigh_put(nr_neigh); + nr_node_put(nr_node); + return 0; + } + + if (nr_neigh == NULL) { + if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) { + if (nr_node) + nr_node_put(nr_node); + return -ENOMEM; + } + + nr_neigh->callsign = *ax25; + nr_neigh->digipeat = NULL; + nr_neigh->ax25 = NULL; + nr_neigh->dev = dev; + nr_neigh->quality = sysctl_netrom_default_path_quality; + nr_neigh->locked = 0; + nr_neigh->count = 0; + nr_neigh->number = nr_neigh_no++; + nr_neigh->failed = 0; + refcount_set(&nr_neigh->refcount, 1); + + if (ax25_digi != NULL && ax25_digi->ndigi > 0) { + nr_neigh->digipeat = kmemdup(ax25_digi, + sizeof(*ax25_digi), + GFP_KERNEL); + if (nr_neigh->digipeat == NULL) { + kfree(nr_neigh); + if (nr_node) + nr_node_put(nr_node); + return -ENOMEM; + } + } + + spin_lock_bh(&nr_neigh_list_lock); + hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list); + nr_neigh_hold(nr_neigh); + spin_unlock_bh(&nr_neigh_list_lock); + } + + if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked) + nr_neigh->quality = quality; + + if (nr_node == NULL) { + if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) { + if (nr_neigh) + nr_neigh_put(nr_neigh); + return -ENOMEM; + } + + nr_node->callsign = *nr; + strcpy(nr_node->mnemonic, mnemonic); + + nr_node->which = 0; + nr_node->count = 1; + refcount_set(&nr_node->refcount, 1); + spin_lock_init(&nr_node->node_lock); + + nr_node->routes[0].quality = quality; + nr_node->routes[0].obs_count = obs_count; + nr_node->routes[0].neighbour = nr_neigh; + + nr_neigh_hold(nr_neigh); + nr_neigh->count++; + + spin_lock_bh(&nr_node_list_lock); + hlist_add_head(&nr_node->node_node, &nr_node_list); + /* refcount initialized at 1 */ + spin_unlock_bh(&nr_node_list_lock); + + nr_neigh_put(nr_neigh); + return 0; + } + nr_node_lock(nr_node); + + if (quality != 0) + strcpy(nr_node->mnemonic, mnemonic); + + for (found = 0, i = 0; i < nr_node->count; i++) { + if (nr_node->routes[i].neighbour == nr_neigh) { + nr_node->routes[i].quality = quality; + nr_node->routes[i].obs_count = obs_count; + found = 1; + break; + } + } + + if (!found) { + /* We have space at the bottom, slot it in */ + if (nr_node->count < 3) { + nr_node->routes[2] = nr_node->routes[1]; + nr_node->routes[1] = nr_node->routes[0]; + + nr_node->routes[0].quality = quality; + nr_node->routes[0].obs_count = obs_count; + nr_node->routes[0].neighbour = nr_neigh; + + nr_node->which++; + nr_node->count++; + nr_neigh_hold(nr_neigh); + nr_neigh->count++; + } else { + /* It must be better than the worst */ + if (quality > nr_node->routes[2].quality) { + nr_node->routes[2].neighbour->count--; + nr_neigh_put(nr_node->routes[2].neighbour); + + if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked) + nr_remove_neigh(nr_node->routes[2].neighbour); + + nr_node->routes[2].quality = quality; + nr_node->routes[2].obs_count = obs_count; + nr_node->routes[2].neighbour = nr_neigh; + + nr_neigh_hold(nr_neigh); + nr_neigh->count++; + } + } + } + + /* Now re-sort the routes in quality order */ + switch (nr_node->count) { + case 3: + re_sort_routes(nr_node, 0, 1); + re_sort_routes(nr_node, 1, 2); + fallthrough; + case 2: + re_sort_routes(nr_node, 0, 1); + case 1: + break; + } + + for (i = 0; i < nr_node->count; i++) { + if (nr_node->routes[i].neighbour == nr_neigh) { + if (i < nr_node->which) + nr_node->which = i; + break; + } + } + + nr_neigh_put(nr_neigh); + nr_node_unlock(nr_node); + nr_node_put(nr_node); + return 0; +} + +static inline void __nr_remove_node(struct nr_node *nr_node) +{ + hlist_del_init(&nr_node->node_node); + nr_node_put(nr_node); +} + +#define nr_remove_node_locked(__node) \ + __nr_remove_node(__node) + +static void nr_remove_node(struct nr_node *nr_node) +{ + spin_lock_bh(&nr_node_list_lock); + __nr_remove_node(nr_node); + spin_unlock_bh(&nr_node_list_lock); +} + +static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh) +{ + hlist_del_init(&nr_neigh->neigh_node); + nr_neigh_put(nr_neigh); +} + +#define nr_remove_neigh_locked(__neigh) \ + __nr_remove_neigh(__neigh) + +static void nr_remove_neigh(struct nr_neigh *nr_neigh) +{ + spin_lock_bh(&nr_neigh_list_lock); + __nr_remove_neigh(nr_neigh); + spin_unlock_bh(&nr_neigh_list_lock); +} + +/* + * "Delete" a node. Strictly speaking remove a route to a node. The node + * is only deleted if no routes are left to it. + */ +static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev) +{ + struct nr_node *nr_node; + struct nr_neigh *nr_neigh; + int i; + + nr_node = nr_node_get(callsign); + + if (nr_node == NULL) + return -EINVAL; + + nr_neigh = nr_neigh_get_dev(neighbour, dev); + + if (nr_neigh == NULL) { + nr_node_put(nr_node); + return -EINVAL; + } + + nr_node_lock(nr_node); + for (i = 0; i < nr_node->count; i++) { + if (nr_node->routes[i].neighbour == nr_neigh) { + nr_neigh->count--; + nr_neigh_put(nr_neigh); + + if (nr_neigh->count == 0 && !nr_neigh->locked) + nr_remove_neigh(nr_neigh); + nr_neigh_put(nr_neigh); + + nr_node->count--; + + if (nr_node->count == 0) { + nr_remove_node(nr_node); + } else { + switch (i) { + case 0: + nr_node->routes[0] = nr_node->routes[1]; + fallthrough; + case 1: + nr_node->routes[1] = nr_node->routes[2]; + case 2: + break; + } + nr_node_put(nr_node); + } + nr_node_unlock(nr_node); + + return 0; + } + } + nr_neigh_put(nr_neigh); + nr_node_unlock(nr_node); + nr_node_put(nr_node); + + return -EINVAL; +} + +/* + * Lock a neighbour with a quality. + */ +static int __must_check nr_add_neigh(ax25_address *callsign, + ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality) +{ + struct nr_neigh *nr_neigh; + + nr_neigh = nr_neigh_get_dev(callsign, dev); + if (nr_neigh) { + nr_neigh->quality = quality; + nr_neigh->locked = 1; + nr_neigh_put(nr_neigh); + return 0; + } + + if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) + return -ENOMEM; + + nr_neigh->callsign = *callsign; + nr_neigh->digipeat = NULL; + nr_neigh->ax25 = NULL; + nr_neigh->dev = dev; + nr_neigh->quality = quality; + nr_neigh->locked = 1; + nr_neigh->count = 0; + nr_neigh->number = nr_neigh_no++; + nr_neigh->failed = 0; + refcount_set(&nr_neigh->refcount, 1); + + if (ax25_digi != NULL && ax25_digi->ndigi > 0) { + nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi), + GFP_KERNEL); + if (nr_neigh->digipeat == NULL) { + kfree(nr_neigh); + return -ENOMEM; + } + } + + spin_lock_bh(&nr_neigh_list_lock); + hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list); + /* refcount is initialized at 1 */ + spin_unlock_bh(&nr_neigh_list_lock); + + return 0; +} + +/* + * "Delete" a neighbour. The neighbour is only removed if the number + * of nodes that may use it is zero. + */ +static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality) +{ + struct nr_neigh *nr_neigh; + + nr_neigh = nr_neigh_get_dev(callsign, dev); + + if (nr_neigh == NULL) return -EINVAL; + + nr_neigh->quality = quality; + nr_neigh->locked = 0; + + if (nr_neigh->count == 0) + nr_remove_neigh(nr_neigh); + nr_neigh_put(nr_neigh); + + return 0; +} + +/* + * Decrement the obsolescence count by one. If a route is reduced to a + * count of zero, remove it. Also remove any unlocked neighbours with + * zero nodes routing via it. + */ +static int nr_dec_obs(void) +{ + struct nr_neigh *nr_neigh; + struct nr_node *s; + struct hlist_node *nodet; + int i; + + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each_safe(s, nodet, &nr_node_list) { + nr_node_lock(s); + for (i = 0; i < s->count; i++) { + switch (s->routes[i].obs_count) { + case 0: /* A locked entry */ + break; + + case 1: /* From 1 -> 0 */ + nr_neigh = s->routes[i].neighbour; + + nr_neigh->count--; + nr_neigh_put(nr_neigh); + + if (nr_neigh->count == 0 && !nr_neigh->locked) + nr_remove_neigh(nr_neigh); + + s->count--; + + switch (i) { + case 0: + s->routes[0] = s->routes[1]; + fallthrough; + case 1: + s->routes[1] = s->routes[2]; + case 2: + break; + } + break; + + default: + s->routes[i].obs_count--; + break; + + } + } + + if (s->count <= 0) + nr_remove_node_locked(s); + nr_node_unlock(s); + } + spin_unlock_bh(&nr_node_list_lock); + + return 0; +} + +/* + * A device has been removed. Remove its routes and neighbours. + */ +void nr_rt_device_down(struct net_device *dev) +{ + struct nr_neigh *s; + struct hlist_node *nodet, *node2t; + struct nr_node *t; + int i; + + spin_lock_bh(&nr_neigh_list_lock); + nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) { + if (s->dev == dev) { + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each_safe(t, node2t, &nr_node_list) { + nr_node_lock(t); + for (i = 0; i < t->count; i++) { + if (t->routes[i].neighbour == s) { + t->count--; + + switch (i) { + case 0: + t->routes[0] = t->routes[1]; + fallthrough; + case 1: + t->routes[1] = t->routes[2]; + case 2: + break; + } + } + } + + if (t->count <= 0) + nr_remove_node_locked(t); + nr_node_unlock(t); + } + spin_unlock_bh(&nr_node_list_lock); + + nr_remove_neigh_locked(s); + } + } + spin_unlock_bh(&nr_neigh_list_lock); +} + +/* + * Check that the device given is a valid AX.25 interface that is "up". + * Or a valid ethernet interface with an AX.25 callsign binding. + */ +static struct net_device *nr_ax25_dev_get(char *devname) +{ + struct net_device *dev; + + if ((dev = dev_get_by_name(&init_net, devname)) == NULL) + return NULL; + + if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25) + return dev; + + dev_put(dev); + return NULL; +} + +/* + * Find the first active NET/ROM device, usually "nr0". + */ +struct net_device *nr_dev_first(void) +{ + struct net_device *dev, *first = NULL; + + rcu_read_lock(); + for_each_netdev_rcu(&init_net, dev) { + if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM) + if (first == NULL || strncmp(dev->name, first->name, 3) < 0) + first = dev; + } + if (first) + dev_hold(first); + rcu_read_unlock(); + + return first; +} + +/* + * Find the NET/ROM device for the given callsign. + */ +struct net_device *nr_dev_get(ax25_address *addr) +{ + struct net_device *dev; + + rcu_read_lock(); + for_each_netdev_rcu(&init_net, dev) { + if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM && + ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) { + dev_hold(dev); + goto out; + } + } + dev = NULL; +out: + rcu_read_unlock(); + return dev; +} + +static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis, + ax25_address *digipeaters) +{ + int i; + + if (ndigis == 0) + return NULL; + + for (i = 0; i < ndigis; i++) { + digi->calls[i] = digipeaters[i]; + digi->repeated[i] = 0; + } + + digi->ndigi = ndigis; + digi->lastrepeat = -1; + + return digi; +} + +/* + * Handle the ioctls that control the routing functions. + */ +int nr_rt_ioctl(unsigned int cmd, void __user *arg) +{ + struct nr_route_struct nr_route; + struct net_device *dev; + ax25_digi digi; + int ret; + + switch (cmd) { + case SIOCADDRT: + if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct))) + return -EFAULT; + if (nr_route.ndigis > AX25_MAX_DIGIS) + return -EINVAL; + if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL) + return -EINVAL; + switch (nr_route.type) { + case NETROM_NODE: + if (strnlen(nr_route.mnemonic, 7) == 7) { + ret = -EINVAL; + break; + } + + ret = nr_add_node(&nr_route.callsign, + nr_route.mnemonic, + &nr_route.neighbour, + nr_call_to_digi(&digi, nr_route.ndigis, + nr_route.digipeaters), + dev, nr_route.quality, + nr_route.obs_count); + break; + case NETROM_NEIGH: + ret = nr_add_neigh(&nr_route.callsign, + nr_call_to_digi(&digi, nr_route.ndigis, + nr_route.digipeaters), + dev, nr_route.quality); + break; + default: + ret = -EINVAL; + } + dev_put(dev); + return ret; + + case SIOCDELRT: + if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct))) + return -EFAULT; + if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL) + return -EINVAL; + switch (nr_route.type) { + case NETROM_NODE: + ret = nr_del_node(&nr_route.callsign, + &nr_route.neighbour, dev); + break; + case NETROM_NEIGH: + ret = nr_del_neigh(&nr_route.callsign, + dev, nr_route.quality); + break; + default: + ret = -EINVAL; + } + dev_put(dev); + return ret; + + case SIOCNRDECOBS: + return nr_dec_obs(); + + default: + return -EINVAL; + } + + return 0; +} + +/* + * A level 2 link has timed out, therefore it appears to be a poor link, + * then don't use that neighbour until it is reset. + */ +void nr_link_failed(ax25_cb *ax25, int reason) +{ + struct nr_neigh *s, *nr_neigh = NULL; + struct nr_node *nr_node = NULL; + + spin_lock_bh(&nr_neigh_list_lock); + nr_neigh_for_each(s, &nr_neigh_list) { + if (s->ax25 == ax25) { + nr_neigh_hold(s); + nr_neigh = s; + break; + } + } + spin_unlock_bh(&nr_neigh_list_lock); + + if (nr_neigh == NULL) + return; + + nr_neigh->ax25 = NULL; + ax25_cb_put(ax25); + + if (++nr_neigh->failed < sysctl_netrom_link_fails_count) { + nr_neigh_put(nr_neigh); + return; + } + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each(nr_node, &nr_node_list) { + nr_node_lock(nr_node); + if (nr_node->which < nr_node->count && + nr_node->routes[nr_node->which].neighbour == nr_neigh) + nr_node->which++; + nr_node_unlock(nr_node); + } + spin_unlock_bh(&nr_node_list_lock); + nr_neigh_put(nr_neigh); +} + +/* + * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb + * indicates an internally generated frame. + */ +int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25) +{ + ax25_address *nr_src, *nr_dest; + struct nr_neigh *nr_neigh; + struct nr_node *nr_node; + struct net_device *dev; + unsigned char *dptr; + ax25_cb *ax25s; + int ret; + struct sk_buff *skbn; + + + nr_src = (ax25_address *)(skb->data + 0); + nr_dest = (ax25_address *)(skb->data + 7); + + if (ax25 != NULL) { + ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat, + ax25->ax25_dev->dev, 0, + sysctl_netrom_obsolescence_count_initialiser); + if (ret) + return ret; + } + + if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */ + if (ax25 == NULL) /* Its from me */ + ret = nr_loopback_queue(skb); + else + ret = nr_rx_frame(skb, dev); + dev_put(dev); + return ret; + } + + if (!sysctl_netrom_routing_control && ax25 != NULL) + return 0; + + /* Its Time-To-Live has expired */ + if (skb->data[14] == 1) { + return 0; + } + + nr_node = nr_node_get(nr_dest); + if (nr_node == NULL) + return 0; + nr_node_lock(nr_node); + + if (nr_node->which >= nr_node->count) { + nr_node_unlock(nr_node); + nr_node_put(nr_node); + return 0; + } + + nr_neigh = nr_node->routes[nr_node->which].neighbour; + + if ((dev = nr_dev_first()) == NULL) { + nr_node_unlock(nr_node); + nr_node_put(nr_node); + return 0; + } + + /* We are going to change the netrom headers so we should get our + own skb, we also did not know until now how much header space + we had to reserve... - RXQ */ + if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) { + nr_node_unlock(nr_node); + nr_node_put(nr_node); + dev_put(dev); + return 0; + } + kfree_skb(skb); + skb=skbn; + skb->data[14]--; + + dptr = skb_push(skb, 1); + *dptr = AX25_P_NETROM; + + ax25s = nr_neigh->ax25; + nr_neigh->ax25 = ax25_send_frame(skb, 256, + (ax25_address *)dev->dev_addr, + &nr_neigh->callsign, + nr_neigh->digipeat, nr_neigh->dev); + if (ax25s) + ax25_cb_put(ax25s); + + dev_put(dev); + ret = (nr_neigh->ax25 != NULL); + nr_node_unlock(nr_node); + nr_node_put(nr_node); + + return ret; +} + +#ifdef CONFIG_PROC_FS + +static void *nr_node_start(struct seq_file *seq, loff_t *pos) + __acquires(&nr_node_list_lock) +{ + spin_lock_bh(&nr_node_list_lock); + return seq_hlist_start_head(&nr_node_list, *pos); +} + +static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_hlist_next(v, &nr_node_list, pos); +} + +static void nr_node_stop(struct seq_file *seq, void *v) + __releases(&nr_node_list_lock) +{ + spin_unlock_bh(&nr_node_list_lock); +} + +static int nr_node_show(struct seq_file *seq, void *v) +{ + char buf[11]; + int i; + + if (v == SEQ_START_TOKEN) + seq_puts(seq, + "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n"); + else { + struct nr_node *nr_node = hlist_entry(v, struct nr_node, + node_node); + + nr_node_lock(nr_node); + seq_printf(seq, "%-9s %-7s %d %d", + ax2asc(buf, &nr_node->callsign), + (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic, + nr_node->which + 1, + nr_node->count); + + for (i = 0; i < nr_node->count; i++) { + seq_printf(seq, " %3d %d %05d", + nr_node->routes[i].quality, + nr_node->routes[i].obs_count, + nr_node->routes[i].neighbour->number); + } + nr_node_unlock(nr_node); + + seq_puts(seq, "\n"); + } + return 0; +} + +const struct seq_operations nr_node_seqops = { + .start = nr_node_start, + .next = nr_node_next, + .stop = nr_node_stop, + .show = nr_node_show, +}; + +static void *nr_neigh_start(struct seq_file *seq, loff_t *pos) + __acquires(&nr_neigh_list_lock) +{ + spin_lock_bh(&nr_neigh_list_lock); + return seq_hlist_start_head(&nr_neigh_list, *pos); +} + +static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_hlist_next(v, &nr_neigh_list, pos); +} + +static void nr_neigh_stop(struct seq_file *seq, void *v) + __releases(&nr_neigh_list_lock) +{ + spin_unlock_bh(&nr_neigh_list_lock); +} + +static int nr_neigh_show(struct seq_file *seq, void *v) +{ + char buf[11]; + int i; + + if (v == SEQ_START_TOKEN) + seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n"); + else { + struct nr_neigh *nr_neigh; + + nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node); + seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d", + nr_neigh->number, + ax2asc(buf, &nr_neigh->callsign), + nr_neigh->dev ? nr_neigh->dev->name : "???", + nr_neigh->quality, + nr_neigh->locked, + nr_neigh->count, + nr_neigh->failed); + + if (nr_neigh->digipeat != NULL) { + for (i = 0; i < nr_neigh->digipeat->ndigi; i++) + seq_printf(seq, " %s", + ax2asc(buf, &nr_neigh->digipeat->calls[i])); + } + + seq_puts(seq, "\n"); + } + return 0; +} + +const struct seq_operations nr_neigh_seqops = { + .start = nr_neigh_start, + .next = nr_neigh_next, + .stop = nr_neigh_stop, + .show = nr_neigh_show, +}; +#endif + +/* + * Free all memory associated with the nodes and routes lists. + */ +void nr_rt_free(void) +{ + struct nr_neigh *s = NULL; + struct nr_node *t = NULL; + struct hlist_node *nodet; + + spin_lock_bh(&nr_neigh_list_lock); + spin_lock_bh(&nr_node_list_lock); + nr_node_for_each_safe(t, nodet, &nr_node_list) { + nr_node_lock(t); + nr_remove_node_locked(t); + nr_node_unlock(t); + } + nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) { + while(s->count) { + s->count--; + nr_neigh_put(s); + } + nr_remove_neigh_locked(s); + } + spin_unlock_bh(&nr_node_list_lock); + spin_unlock_bh(&nr_neigh_list_lock); +} diff --git a/net/netrom/nr_subr.c b/net/netrom/nr_subr.c new file mode 100644 index 000000000..e2d2af924 --- /dev/null +++ b/net/netrom/nr_subr.c @@ -0,0 +1,279 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <linux/slab.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/netrom.h> + +/* + * This routine purges all of the queues of frames. + */ +void nr_clear_queues(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + skb_queue_purge(&sk->sk_write_queue); + skb_queue_purge(&nr->ack_queue); + skb_queue_purge(&nr->reseq_queue); + skb_queue_purge(&nr->frag_queue); +} + +/* + * This routine purges the input queue of those frames that have been + * acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the + * SDL diagram. + */ +void nr_frames_acked(struct sock *sk, unsigned short nr) +{ + struct nr_sock *nrom = nr_sk(sk); + struct sk_buff *skb; + + /* + * Remove all the ack-ed frames from the ack queue. + */ + if (nrom->va != nr) { + while (skb_peek(&nrom->ack_queue) != NULL && nrom->va != nr) { + skb = skb_dequeue(&nrom->ack_queue); + kfree_skb(skb); + nrom->va = (nrom->va + 1) % NR_MODULUS; + } + } +} + +/* + * Requeue all the un-ack-ed frames on the output queue to be picked + * up by nr_kick called from the timer. This arrangement handles the + * possibility of an empty output queue. + */ +void nr_requeue_frames(struct sock *sk) +{ + struct sk_buff *skb, *skb_prev = NULL; + + while ((skb = skb_dequeue(&nr_sk(sk)->ack_queue)) != NULL) { + if (skb_prev == NULL) + skb_queue_head(&sk->sk_write_queue, skb); + else + skb_append(skb_prev, skb, &sk->sk_write_queue); + skb_prev = skb; + } +} + +/* + * Validate that the value of nr is between va and vs. Return true or + * false for testing. + */ +int nr_validate_nr(struct sock *sk, unsigned short nr) +{ + struct nr_sock *nrom = nr_sk(sk); + unsigned short vc = nrom->va; + + while (vc != nrom->vs) { + if (nr == vc) return 1; + vc = (vc + 1) % NR_MODULUS; + } + + return nr == nrom->vs; +} + +/* + * Check that ns is within the receive window. + */ +int nr_in_rx_window(struct sock *sk, unsigned short ns) +{ + struct nr_sock *nr = nr_sk(sk); + unsigned short vc = nr->vr; + unsigned short vt = (nr->vl + nr->window) % NR_MODULUS; + + while (vc != vt) { + if (ns == vc) return 1; + vc = (vc + 1) % NR_MODULUS; + } + + return 0; +} + +/* + * This routine is called when the HDLC layer internally generates a + * control frame. + */ +void nr_write_internal(struct sock *sk, int frametype) +{ + struct nr_sock *nr = nr_sk(sk); + struct sk_buff *skb; + unsigned char *dptr; + int len, timeout; + + len = NR_TRANSPORT_LEN; + + switch (frametype & 0x0F) { + case NR_CONNREQ: + len += 17; + break; + case NR_CONNACK: + len += (nr->bpqext) ? 2 : 1; + break; + case NR_DISCREQ: + case NR_DISCACK: + case NR_INFOACK: + break; + default: + printk(KERN_ERR "NET/ROM: nr_write_internal - invalid frame type %d\n", frametype); + return; + } + + skb = alloc_skb(NR_NETWORK_LEN + len, GFP_ATOMIC); + if (!skb) + return; + + /* + * Space for AX.25 and NET/ROM network header + */ + skb_reserve(skb, NR_NETWORK_LEN); + + dptr = skb_put(skb, len); + + switch (frametype & 0x0F) { + case NR_CONNREQ: + timeout = nr->t1 / HZ; + *dptr++ = nr->my_index; + *dptr++ = nr->my_id; + *dptr++ = 0; + *dptr++ = 0; + *dptr++ = frametype; + *dptr++ = nr->window; + memcpy(dptr, &nr->user_addr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] &= ~AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + memcpy(dptr, &nr->source_addr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] &= ~AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + *dptr++ = timeout % 256; + *dptr++ = timeout / 256; + break; + + case NR_CONNACK: + *dptr++ = nr->your_index; + *dptr++ = nr->your_id; + *dptr++ = nr->my_index; + *dptr++ = nr->my_id; + *dptr++ = frametype; + *dptr++ = nr->window; + if (nr->bpqext) *dptr++ = sysctl_netrom_network_ttl_initialiser; + break; + + case NR_DISCREQ: + case NR_DISCACK: + *dptr++ = nr->your_index; + *dptr++ = nr->your_id; + *dptr++ = 0; + *dptr++ = 0; + *dptr++ = frametype; + break; + + case NR_INFOACK: + *dptr++ = nr->your_index; + *dptr++ = nr->your_id; + *dptr++ = 0; + *dptr++ = nr->vr; + *dptr++ = frametype; + break; + } + + nr_transmit_buffer(sk, skb); +} + +/* + * This routine is called to send an error reply. + */ +void __nr_transmit_reply(struct sk_buff *skb, int mine, unsigned char cmdflags) +{ + struct sk_buff *skbn; + unsigned char *dptr; + int len; + + len = NR_NETWORK_LEN + NR_TRANSPORT_LEN + 1; + + if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL) + return; + + skb_reserve(skbn, 0); + + dptr = skb_put(skbn, NR_NETWORK_LEN + NR_TRANSPORT_LEN); + + skb_copy_from_linear_data_offset(skb, 7, dptr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] &= ~AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + + skb_copy_from_linear_data(skb, dptr, AX25_ADDR_LEN); + dptr[6] &= ~AX25_CBIT; + dptr[6] |= AX25_EBIT; + dptr[6] |= AX25_SSSID_SPARE; + dptr += AX25_ADDR_LEN; + + *dptr++ = sysctl_netrom_network_ttl_initialiser; + + if (mine) { + *dptr++ = 0; + *dptr++ = 0; + *dptr++ = skb->data[15]; + *dptr++ = skb->data[16]; + } else { + *dptr++ = skb->data[15]; + *dptr++ = skb->data[16]; + *dptr++ = 0; + *dptr++ = 0; + } + + *dptr++ = cmdflags; + *dptr++ = 0; + + if (!nr_route_frame(skbn, NULL)) + kfree_skb(skbn); +} + +void nr_disconnect(struct sock *sk, int reason) +{ + nr_stop_t1timer(sk); + nr_stop_t2timer(sk); + nr_stop_t4timer(sk); + nr_stop_idletimer(sk); + + nr_clear_queues(sk); + + nr_sk(sk)->state = NR_STATE_0; + + sk->sk_state = TCP_CLOSE; + sk->sk_err = reason; + sk->sk_shutdown |= SEND_SHUTDOWN; + + if (!sock_flag(sk, SOCK_DEAD)) { + sk->sk_state_change(sk); + sock_set_flag(sk, SOCK_DEAD); + } +} diff --git a/net/netrom/nr_timer.c b/net/netrom/nr_timer.c new file mode 100644 index 000000000..4e7c968cd --- /dev/null +++ b/net/netrom/nr_timer.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) + * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org) + */ +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/socket.h> +#include <linux/in.h> +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/sockios.h> +#include <linux/net.h> +#include <net/ax25.h> +#include <linux/inet.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <net/netrom.h> + +static void nr_heartbeat_expiry(struct timer_list *); +static void nr_t1timer_expiry(struct timer_list *); +static void nr_t2timer_expiry(struct timer_list *); +static void nr_t4timer_expiry(struct timer_list *); +static void nr_idletimer_expiry(struct timer_list *); + +void nr_init_timers(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + timer_setup(&nr->t1timer, nr_t1timer_expiry, 0); + timer_setup(&nr->t2timer, nr_t2timer_expiry, 0); + timer_setup(&nr->t4timer, nr_t4timer_expiry, 0); + timer_setup(&nr->idletimer, nr_idletimer_expiry, 0); + + /* initialized by sock_init_data */ + sk->sk_timer.function = nr_heartbeat_expiry; +} + +void nr_start_t1timer(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + sk_reset_timer(sk, &nr->t1timer, jiffies + nr->t1); +} + +void nr_start_t2timer(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + sk_reset_timer(sk, &nr->t2timer, jiffies + nr->t2); +} + +void nr_start_t4timer(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + sk_reset_timer(sk, &nr->t4timer, jiffies + nr->t4); +} + +void nr_start_idletimer(struct sock *sk) +{ + struct nr_sock *nr = nr_sk(sk); + + if (nr->idle > 0) + sk_reset_timer(sk, &nr->idletimer, jiffies + nr->idle); +} + +void nr_start_heartbeat(struct sock *sk) +{ + sk_reset_timer(sk, &sk->sk_timer, jiffies + 5 * HZ); +} + +void nr_stop_t1timer(struct sock *sk) +{ + sk_stop_timer(sk, &nr_sk(sk)->t1timer); +} + +void nr_stop_t2timer(struct sock *sk) +{ + sk_stop_timer(sk, &nr_sk(sk)->t2timer); +} + +void nr_stop_t4timer(struct sock *sk) +{ + sk_stop_timer(sk, &nr_sk(sk)->t4timer); +} + +void nr_stop_idletimer(struct sock *sk) +{ + sk_stop_timer(sk, &nr_sk(sk)->idletimer); +} + +void nr_stop_heartbeat(struct sock *sk) +{ + sk_stop_timer(sk, &sk->sk_timer); +} + +int nr_t1timer_running(struct sock *sk) +{ + return timer_pending(&nr_sk(sk)->t1timer); +} + +static void nr_heartbeat_expiry(struct timer_list *t) +{ + struct sock *sk = from_timer(sk, t, sk_timer); + struct nr_sock *nr = nr_sk(sk); + + bh_lock_sock(sk); + switch (nr->state) { + case NR_STATE_0: + /* Magic here: If we listen() and a new link dies before it + is accepted() it isn't 'dead' so doesn't get removed. */ + if (sock_flag(sk, SOCK_DESTROY) || + (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) { + sock_hold(sk); + bh_unlock_sock(sk); + nr_destroy_socket(sk); + goto out; + } + break; + + case NR_STATE_3: + /* + * Check for the state of the receive buffer. + */ + if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) && + (nr->condition & NR_COND_OWN_RX_BUSY)) { + nr->condition &= ~NR_COND_OWN_RX_BUSY; + nr->condition &= ~NR_COND_ACK_PENDING; + nr->vl = nr->vr; + nr_write_internal(sk, NR_INFOACK); + break; + } + break; + } + + nr_start_heartbeat(sk); + bh_unlock_sock(sk); +out: + sock_put(sk); +} + +static void nr_t2timer_expiry(struct timer_list *t) +{ + struct nr_sock *nr = from_timer(nr, t, t2timer); + struct sock *sk = &nr->sock; + + bh_lock_sock(sk); + if (nr->condition & NR_COND_ACK_PENDING) { + nr->condition &= ~NR_COND_ACK_PENDING; + nr_enquiry_response(sk); + } + bh_unlock_sock(sk); + sock_put(sk); +} + +static void nr_t4timer_expiry(struct timer_list *t) +{ + struct nr_sock *nr = from_timer(nr, t, t4timer); + struct sock *sk = &nr->sock; + + bh_lock_sock(sk); + nr_sk(sk)->condition &= ~NR_COND_PEER_RX_BUSY; + bh_unlock_sock(sk); + sock_put(sk); +} + +static void nr_idletimer_expiry(struct timer_list *t) +{ + struct nr_sock *nr = from_timer(nr, t, idletimer); + struct sock *sk = &nr->sock; + + bh_lock_sock(sk); + + nr_clear_queues(sk); + + nr->n2count = 0; + nr_write_internal(sk, NR_DISCREQ); + nr->state = NR_STATE_2; + + nr_start_t1timer(sk); + nr_stop_t2timer(sk); + nr_stop_t4timer(sk); + + sk->sk_state = TCP_CLOSE; + sk->sk_err = 0; + sk->sk_shutdown |= SEND_SHUTDOWN; + + if (!sock_flag(sk, SOCK_DEAD)) { + sk->sk_state_change(sk); + sock_set_flag(sk, SOCK_DEAD); + } + bh_unlock_sock(sk); + sock_put(sk); +} + +static void nr_t1timer_expiry(struct timer_list *t) +{ + struct nr_sock *nr = from_timer(nr, t, t1timer); + struct sock *sk = &nr->sock; + + bh_lock_sock(sk); + switch (nr->state) { + case NR_STATE_1: + if (nr->n2count == nr->n2) { + nr_disconnect(sk, ETIMEDOUT); + goto out; + } else { + nr->n2count++; + nr_write_internal(sk, NR_CONNREQ); + } + break; + + case NR_STATE_2: + if (nr->n2count == nr->n2) { + nr_disconnect(sk, ETIMEDOUT); + goto out; + } else { + nr->n2count++; + nr_write_internal(sk, NR_DISCREQ); + } + break; + + case NR_STATE_3: + if (nr->n2count == nr->n2) { + nr_disconnect(sk, ETIMEDOUT); + goto out; + } else { + nr->n2count++; + nr_requeue_frames(sk); + } + break; + } + + nr_start_t1timer(sk); +out: + bh_unlock_sock(sk); + sock_put(sk); +} diff --git a/net/netrom/sysctl_net_netrom.c b/net/netrom/sysctl_net_netrom.c new file mode 100644 index 000000000..79fb2d3f4 --- /dev/null +++ b/net/netrom/sysctl_net_netrom.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Copyright (C) 1996 Mike Shaver (shaver@zeroknowledge.com) + */ +#include <linux/mm.h> +#include <linux/sysctl.h> +#include <linux/init.h> +#include <net/ax25.h> +#include <net/netrom.h> + +/* + * Values taken from NET/ROM documentation. + */ +static int min_quality[] = {0}, max_quality[] = {255}; +static int min_obs[] = {0}, max_obs[] = {255}; +static int min_ttl[] = {0}, max_ttl[] = {255}; +static int min_t1[] = {5 * HZ}; +static int max_t1[] = {600 * HZ}; +static int min_n2[] = {2}, max_n2[] = {127}; +static int min_t2[] = {1 * HZ}; +static int max_t2[] = {60 * HZ}; +static int min_t4[] = {1 * HZ}; +static int max_t4[] = {1000 * HZ}; +static int min_window[] = {1}, max_window[] = {127}; +static int min_idle[] = {0 * HZ}; +static int max_idle[] = {65535 * HZ}; +static int min_route[] = {0}, max_route[] = {1}; +static int min_fails[] = {1}, max_fails[] = {10}; +static int min_reset[] = {0}, max_reset[] = {1}; + +static struct ctl_table_header *nr_table_header; + +static struct ctl_table nr_table[] = { + { + .procname = "default_path_quality", + .data = &sysctl_netrom_default_path_quality, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_quality, + .extra2 = &max_quality + }, + { + .procname = "obsolescence_count_initialiser", + .data = &sysctl_netrom_obsolescence_count_initialiser, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_obs, + .extra2 = &max_obs + }, + { + .procname = "network_ttl_initialiser", + .data = &sysctl_netrom_network_ttl_initialiser, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_ttl, + .extra2 = &max_ttl + }, + { + .procname = "transport_timeout", + .data = &sysctl_netrom_transport_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_t1, + .extra2 = &max_t1 + }, + { + .procname = "transport_maximum_tries", + .data = &sysctl_netrom_transport_maximum_tries, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_n2, + .extra2 = &max_n2 + }, + { + .procname = "transport_acknowledge_delay", + .data = &sysctl_netrom_transport_acknowledge_delay, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_t2, + .extra2 = &max_t2 + }, + { + .procname = "transport_busy_delay", + .data = &sysctl_netrom_transport_busy_delay, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_t4, + .extra2 = &max_t4 + }, + { + .procname = "transport_requested_window_size", + .data = &sysctl_netrom_transport_requested_window_size, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_window, + .extra2 = &max_window + }, + { + .procname = "transport_no_activity_timeout", + .data = &sysctl_netrom_transport_no_activity_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_idle, + .extra2 = &max_idle + }, + { + .procname = "routing_control", + .data = &sysctl_netrom_routing_control, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_route, + .extra2 = &max_route + }, + { + .procname = "link_fails_count", + .data = &sysctl_netrom_link_fails_count, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_fails, + .extra2 = &max_fails + }, + { + .procname = "reset", + .data = &sysctl_netrom_reset_circuit, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_reset, + .extra2 = &max_reset + }, + { } +}; + +int __init nr_register_sysctl(void) +{ + nr_table_header = register_net_sysctl(&init_net, "net/netrom", nr_table); + if (!nr_table_header) + return -ENOMEM; + return 0; +} + +void nr_unregister_sysctl(void) +{ + unregister_net_sysctl_table(nr_table_header); +} |