linux/net/netrom/af_netrom.c
Oliver Hartkopp f4b41f062c net: remove noblock parameter from skb_recv_datagram()
skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-06 13:45:26 +01:00

1528 lines
32 KiB
C

// 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 (sk->sk_state != TCP_LISTEN) {
memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
sk->sk_max_ack_backlog = backlog;
sk->sk_state = TCP_LISTEN;
release_sock(sk);
return 0;
}
release_sock(sk);
return -EOPNOTSUPP;
}
static struct proto nr_proto = {
.name = "NETROM",
.owner = THIS_MODULE,
.obj_size = sizeof(struct nr_sock),
};
static int nr_create(struct net *net, struct socket *sock, int protocol,
int kern)
{
struct sock *sk;
struct nr_sock *nr;
if (!net_eq(net, &init_net))
return -EAFNOSUPPORT;
if (sock->type != SOCK_SEQPACKET || protocol != 0)
return -ESOCKTNOSUPPORT;
sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
if (sk == NULL)
return -ENOMEM;
nr = nr_sk(sk);
sock_init_data(sock, sk);
sock->ops = &nr_proto_ops;
sk->sk_protocol = protocol;
skb_queue_head_init(&nr->ack_queue);
skb_queue_head_init(&nr->reseq_queue);
skb_queue_head_init(&nr->frag_queue);
nr_init_timers(sk);
nr->t1 =
msecs_to_jiffies(sysctl_netrom_transport_timeout);
nr->t2 =
msecs_to_jiffies(sysctl_netrom_transport_acknowledge_delay);
nr->n2 =
msecs_to_jiffies(sysctl_netrom_transport_maximum_tries);
nr->t4 =
msecs_to_jiffies(sysctl_netrom_transport_busy_delay);
nr->idle =
msecs_to_jiffies(sysctl_netrom_transport_no_activity_timeout);
nr->window = sysctl_netrom_transport_requested_window_size;
nr->bpqext = 1;
nr->state = NR_STATE_0;
return 0;
}
static struct sock *nr_make_new(struct sock *osk)
{
struct sock *sk;
struct nr_sock *nr, *onr;
if (osk->sk_type != SOCK_SEQPACKET)
return NULL;
sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
if (sk == NULL)
return NULL;
nr = nr_sk(sk);
sock_init_data(NULL, sk);
sk->sk_type = osk->sk_type;
sk->sk_priority = osk->sk_priority;
sk->sk_protocol = osk->sk_protocol;
sk->sk_rcvbuf = osk->sk_rcvbuf;
sk->sk_sndbuf = osk->sk_sndbuf;
sk->sk_state = TCP_ESTABLISHED;
sock_copy_flags(sk, osk);
skb_queue_head_init(&nr->ack_queue);
skb_queue_head_init(&nr->reseq_queue);
skb_queue_head_init(&nr->frag_queue);
nr_init_timers(sk);
onr = nr_sk(osk);
nr->t1 = onr->t1;
nr->t2 = onr->t2;
nr->n2 = onr->n2;
nr->t4 = onr->t4;
nr->idle = onr->idle;
nr->window = onr->window;
nr->device = onr->device;
nr->bpqext = onr->bpqext;
return sk;
}
static int nr_release(struct socket *sock)
{
struct sock *sk = sock->sk;
struct nr_sock *nr;
if (sk == NULL) return 0;
sock_hold(sk);
sock_orphan(sk);
lock_sock(sk);
nr = nr_sk(sk);
switch (nr->state) {
case NR_STATE_0:
case NR_STATE_1:
case NR_STATE_2:
nr_disconnect(sk, 0);
nr_destroy_socket(sk);
break;
case NR_STATE_3:
nr_clear_queues(sk);
nr->n2count = 0;
nr_write_internal(sk, NR_DISCREQ);
nr_start_t1timer(sk);
nr_stop_t2timer(sk);
nr_stop_t4timer(sk);
nr_stop_idletimer(sk);
nr->state = NR_STATE_2;
sk->sk_state = TCP_CLOSE;
sk->sk_shutdown |= SEND_SHUTDOWN;
sk->sk_state_change(sk);
sock_set_flag(sk, SOCK_DESTROY);
break;
default:
break;
}
sock->sk = NULL;
release_sock(sk);
sock_put(sk);
return 0;
}
static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sock *sk = sock->sk;
struct nr_sock *nr = nr_sk(sk);
struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
struct net_device *dev;
ax25_uid_assoc *user;
ax25_address *source;
lock_sock(sk);
if (!sock_flag(sk, SOCK_ZAPPED)) {
release_sock(sk);
return -EINVAL;
}
if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
release_sock(sk);
return -EINVAL;
}
if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
release_sock(sk);
return -EINVAL;
}
if (addr->fsa_ax25.sax25_family != AF_NETROM) {
release_sock(sk);
return -EINVAL;
}
if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
release_sock(sk);
return -EADDRNOTAVAIL;
}
/*
* Only the super user can set an arbitrary user callsign.
*/
if (addr->fsa_ax25.sax25_ndigis == 1) {
if (!capable(CAP_NET_BIND_SERVICE)) {
dev_put(dev);
release_sock(sk);
return -EPERM;
}
nr->user_addr = addr->fsa_digipeater[0];
nr->source_addr = addr->fsa_ax25.sax25_call;
} else {
source = &addr->fsa_ax25.sax25_call;
user = ax25_findbyuid(current_euid());
if (user) {
nr->user_addr = user->call;
ax25_uid_put(user);
} else {
if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
release_sock(sk);
dev_put(dev);
return -EPERM;
}
nr->user_addr = *source;
}
nr->source_addr = *source;
}
nr->device = dev;
nr_insert_socket(sk);
sock_reset_flag(sk, SOCK_ZAPPED);
dev_put(dev);
release_sock(sk);
return 0;
}
static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
int addr_len, int flags)
{
struct sock *sk = sock->sk;
struct nr_sock *nr = nr_sk(sk);
struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
const ax25_address *source = NULL;
ax25_uid_assoc *user;
struct net_device *dev;
int err = 0;
lock_sock(sk);
if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
sock->state = SS_CONNECTED;
goto out_release; /* Connect completed during a ERESTARTSYS event */
}
if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
sock->state = SS_UNCONNECTED;
err = -ECONNREFUSED;
goto out_release;
}
if (sk->sk_state == TCP_ESTABLISHED) {
err = -EISCONN; /* No reconnect on a seqpacket socket */
goto out_release;
}
sk->sk_state = TCP_CLOSE;
sock->state = SS_UNCONNECTED;
if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
err = -EINVAL;
goto out_release;
}
if (addr->sax25_family != AF_NETROM) {
err = -EINVAL;
goto out_release;
}
if (sock_flag(sk, SOCK_ZAPPED)) { /* Must bind first - autobinding in this may or may not work */
sock_reset_flag(sk, SOCK_ZAPPED);
if ((dev = nr_dev_first()) == NULL) {
err = -ENETUNREACH;
goto out_release;
}
source = (const ax25_address *)dev->dev_addr;
user = ax25_findbyuid(current_euid());
if (user) {
nr->user_addr = user->call;
ax25_uid_put(user);
} else {
if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
dev_put(dev);
err = -EPERM;
goto out_release;
}
nr->user_addr = *source;
}
nr->source_addr = *source;
nr->device = dev;
dev_put(dev);
nr_insert_socket(sk); /* Finish the bind */
}
nr->dest_addr = addr->sax25_call;
release_sock(sk);
circuit = nr_find_next_circuit();
lock_sock(sk);
nr->my_index = circuit / 256;
nr->my_id = circuit % 256;
circuit++;
/* Move to connecting socket, start sending Connect Requests */
sock->state = SS_CONNECTING;
sk->sk_state = TCP_SYN_SENT;
nr_establish_data_link(sk);
nr->state = NR_STATE_1;
nr_start_heartbeat(sk);
/* Now the loop */
if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
err = -EINPROGRESS;
goto out_release;
}
/*
* A Connect Ack with Choke or timeout or failed routing will go to
* closed.
*/
if (sk->sk_state == TCP_SYN_SENT) {
DEFINE_WAIT(wait);
for (;;) {
prepare_to_wait(sk_sleep(sk), &wait,
TASK_INTERRUPTIBLE);
if (sk->sk_state != TCP_SYN_SENT)
break;
if (!signal_pending(current)) {
release_sock(sk);
schedule();
lock_sock(sk);
continue;
}
err = -ERESTARTSYS;
break;
}
finish_wait(sk_sleep(sk), &wait);
if (err)
goto out_release;
}
if (sk->sk_state != TCP_ESTABLISHED) {
sock->state = SS_UNCONNECTED;
err = sock_error(sk); /* Always set at this point */
goto out_release;
}
sock->state = SS_CONNECTED;
out_release:
release_sock(sk);
return err;
}
static int nr_accept(struct socket *sock, struct socket *newsock, int flags,
bool kern)
{
struct sk_buff *skb;
struct sock *newsk;
DEFINE_WAIT(wait);
struct sock *sk;
int err = 0;
if ((sk = sock->sk) == NULL)
return -EINVAL;
lock_sock(sk);
if (sk->sk_type != SOCK_SEQPACKET) {
err = -EOPNOTSUPP;
goto out_release;
}
if (sk->sk_state != TCP_LISTEN) {
err = -EINVAL;
goto out_release;
}
/*
* The write queue this time is holding sockets ready to use
* hooked into the SABM we saved
*/
for (;;) {
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
skb = skb_dequeue(&sk->sk_receive_queue);
if (skb)
break;
if (flags & O_NONBLOCK) {
err = -EWOULDBLOCK;
break;
}
if (!signal_pending(current)) {
release_sock(sk);
schedule();
lock_sock(sk);
continue;
}
err = -ERESTARTSYS;
break;
}
finish_wait(sk_sleep(sk), &wait);
if (err)
goto out_release;
newsk = skb->sk;
sock_graft(newsk, newsock);
/* Now attach up the new socket */
kfree_skb(skb);
sk_acceptq_removed(sk);
out_release:
release_sock(sk);
return err;
}
static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
int peer)
{
struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
struct sock *sk = sock->sk;
struct nr_sock *nr = nr_sk(sk);
int uaddr_len;
memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
lock_sock(sk);
if (peer != 0) {
if (sk->sk_state != TCP_ESTABLISHED) {
release_sock(sk);
return -ENOTCONN;
}
sax->fsa_ax25.sax25_family = AF_NETROM;
sax->fsa_ax25.sax25_ndigis = 1;
sax->fsa_ax25.sax25_call = nr->user_addr;
memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
sax->fsa_digipeater[0] = nr->dest_addr;
uaddr_len = sizeof(struct full_sockaddr_ax25);
} else {
sax->fsa_ax25.sax25_family = AF_NETROM;
sax->fsa_ax25.sax25_ndigis = 0;
sax->fsa_ax25.sax25_call = nr->source_addr;
uaddr_len = sizeof(struct sockaddr_ax25);
}
release_sock(sk);
return uaddr_len;
}
int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
{
struct sock *sk;
struct sock *make;
struct nr_sock *nr_make;
ax25_address *src, *dest, *user;
unsigned short circuit_index, circuit_id;
unsigned short peer_circuit_index, peer_circuit_id;
unsigned short frametype, flags, window, timeout;
int ret;
skb_orphan(skb);
/*
* skb->data points to the netrom frame start
*/
src = (ax25_address *)(skb->data + 0);
dest = (ax25_address *)(skb->data + 7);
circuit_index = skb->data[15];
circuit_id = skb->data[16];
peer_circuit_index = skb->data[17];
peer_circuit_id = skb->data[18];
frametype = skb->data[19] & 0x0F;
flags = skb->data[19] & 0xF0;
/*
* Check for an incoming IP over NET/ROM frame.
*/
if (frametype == NR_PROTOEXT &&
circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
skb_reset_transport_header(skb);
return nr_rx_ip(skb, dev);
}
/*
* Find an existing socket connection, based on circuit ID, if it's
* a Connect Request base it on their circuit ID.
*
* Circuit ID 0/0 is not valid but it could still be a "reset" for a
* circuit that no longer exists at the other end ...
*/
sk = NULL;
if (circuit_index == 0 && circuit_id == 0) {
if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
} else {
if (frametype == NR_CONNREQ)
sk = nr_find_peer(circuit_index, circuit_id, src);
else
sk = nr_find_socket(circuit_index, circuit_id);
}
if (sk != NULL) {
bh_lock_sock(sk);
skb_reset_transport_header(skb);
if (frametype == NR_CONNACK && skb->len == 22)
nr_sk(sk)->bpqext = 1;
else
nr_sk(sk)->bpqext = 0;
ret = nr_process_rx_frame(sk, skb);
bh_unlock_sock(sk);
sock_put(sk);
return ret;
}
/*
* Now it should be a CONNREQ.
*/
if (frametype != NR_CONNREQ) {
/*
* Here it would be nice to be able to send a reset but
* NET/ROM doesn't have one. We've tried to extend the protocol
* by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
* apparently kills BPQ boxes... :-(
* So now we try to follow the established behaviour of
* G8PZT's Xrouter which is sending packets with command type 7
* as an extension of the protocol.
*/
if (sysctl_netrom_reset_circuit &&
(frametype != NR_RESET || flags != 0))
nr_transmit_reset(skb, 1);
return 0;
}
sk = nr_find_listener(dest);
user = (ax25_address *)(skb->data + 21);
if (sk == NULL || sk_acceptq_is_full(sk) ||
(make = nr_make_new(sk)) == NULL) {
nr_transmit_refusal(skb, 0);
if (sk)
sock_put(sk);
return 0;
}
bh_lock_sock(sk);
window = skb->data[20];
sock_hold(make);
skb->sk = make;
skb->destructor = sock_efree;
make->sk_state = TCP_ESTABLISHED;
/* Fill in his circuit details */
nr_make = nr_sk(make);
nr_make->source_addr = *dest;
nr_make->dest_addr = *src;
nr_make->user_addr = *user;
nr_make->your_index = circuit_index;
nr_make->your_id = circuit_id;
bh_unlock_sock(sk);
circuit = nr_find_next_circuit();
bh_lock_sock(sk);
nr_make->my_index = circuit / 256;
nr_make->my_id = circuit % 256;
circuit++;
/* Window negotiation */
if (window < nr_make->window)
nr_make->window = window;
/* L4 timeout negotiation */
if (skb->len == 37) {
timeout = skb->data[36] * 256 + skb->data[35];
if (timeout * HZ < nr_make->t1)
nr_make->t1 = timeout * HZ;
nr_make->bpqext = 1;
} else {
nr_make->bpqext = 0;
}
nr_write_internal(make, NR_CONNACK);
nr_make->condition = 0x00;
nr_make->vs = 0;
nr_make->va = 0;
nr_make->vr = 0;
nr_make->vl = 0;
nr_make->state = NR_STATE_3;
sk_acceptq_added(sk);
skb_queue_head(&sk->sk_receive_queue, skb);
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_data_ready(sk);
bh_unlock_sock(sk);
sock_put(sk);
nr_insert_socket(make);
nr_start_heartbeat(make);
nr_start_idletimer(make);
return 1;
}
static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
{
struct sock *sk = sock->sk;
struct nr_sock *nr = nr_sk(sk);
DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
int err;
struct sockaddr_ax25 sax;
struct sk_buff *skb;
unsigned char *asmptr;
int size;
if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
return -EINVAL;
lock_sock(sk);
if (sock_flag(sk, SOCK_ZAPPED)) {
err = -EADDRNOTAVAIL;
goto out;
}
if (sk->sk_shutdown & SEND_SHUTDOWN) {
send_sig(SIGPIPE, current, 0);
err = -EPIPE;
goto out;
}
if (nr->device == NULL) {
err = -ENETUNREACH;
goto out;
}
if (usax) {
if (msg->msg_namelen < sizeof(sax)) {
err = -EINVAL;
goto out;
}
sax = *usax;
if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
err = -EISCONN;
goto out;
}
if (sax.sax25_family != AF_NETROM) {
err = -EINVAL;
goto out;
}
} else {
if (sk->sk_state != TCP_ESTABLISHED) {
err = -ENOTCONN;
goto out;
}
sax.sax25_family = AF_NETROM;
sax.sax25_call = nr->dest_addr;
}
/* Build a packet - the conventional user limit is 236 bytes. We can
do ludicrously large NetROM frames but must not overflow */
if (len > 65536) {
err = -EMSGSIZE;
goto out;
}
size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
goto out;
skb_reserve(skb, size - len);
skb_reset_transport_header(skb);
/*
* Push down the NET/ROM header
*/
asmptr = skb_push(skb, NR_TRANSPORT_LEN);
/* Build a NET/ROM Transport header */
*asmptr++ = nr->your_index;
*asmptr++ = nr->your_id;
*asmptr++ = 0; /* To be filled in later */
*asmptr++ = 0; /* Ditto */
*asmptr++ = NR_INFO;
/*
* Put the data on the end
*/
skb_put(skb, len);
/* User data follows immediately after the NET/ROM transport header */
if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
kfree_skb(skb);
err = -EFAULT;
goto out;
}
if (sk->sk_state != TCP_ESTABLISHED) {
kfree_skb(skb);
err = -ENOTCONN;
goto out;
}
nr_output(sk, skb); /* Shove it onto the queue */
err = len;
out:
release_sock(sk);
return err;
}
static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
int flags)
{
struct sock *sk = sock->sk;
DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
size_t copied;
struct sk_buff *skb;
int er;
/*
* This works for seqpacket too. The receiver has ordered the queue for
* us! We do one quick check first though
*/
lock_sock(sk);
if (sk->sk_state != TCP_ESTABLISHED) {
release_sock(sk);
return -ENOTCONN;
}
/* Now we can treat all alike */
skb = skb_recv_datagram(sk, flags, &er);
if (!skb) {
release_sock(sk);
return er;
}
skb_reset_transport_header(skb);
copied = skb->len;
if (copied > size) {
copied = size;
msg->msg_flags |= MSG_TRUNC;
}
er = skb_copy_datagram_msg(skb, 0, msg, copied);
if (er < 0) {
skb_free_datagram(sk, skb);
release_sock(sk);
return er;
}
if (sax != NULL) {
memset(sax, 0, sizeof(*sax));
sax->sax25_family = AF_NETROM;
skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
AX25_ADDR_LEN);
msg->msg_namelen = sizeof(*sax);
}
skb_free_datagram(sk, skb);
release_sock(sk);
return copied;
}
static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
{
struct sock *sk = sock->sk;
void __user *argp = (void __user *)arg;
switch (cmd) {
case TIOCOUTQ: {
long amount;
lock_sock(sk);
amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
if (amount < 0)
amount = 0;
release_sock(sk);
return put_user(amount, (int __user *)argp);
}
case TIOCINQ: {
struct sk_buff *skb;
long amount = 0L;
lock_sock(sk);
/* These two are safe on a single CPU system as only user tasks fiddle here */
if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
amount = skb->len;
release_sock(sk);
return put_user(amount, (int __user *)argp);
}
case SIOCGIFADDR:
case SIOCSIFADDR:
case SIOCGIFDSTADDR:
case SIOCSIFDSTADDR:
case SIOCGIFBRDADDR:
case SIOCSIFBRDADDR:
case SIOCGIFNETMASK:
case SIOCSIFNETMASK:
case SIOCGIFMETRIC:
case SIOCSIFMETRIC:
return -EINVAL;
case SIOCADDRT:
case SIOCDELRT:
case SIOCNRDECOBS:
if (!capable(CAP_NET_ADMIN))
return -EPERM;
return nr_rt_ioctl(cmd, argp);
default:
return -ENOIOCTLCMD;
}
return 0;
}
#ifdef CONFIG_PROC_FS
static void *nr_info_start(struct seq_file *seq, loff_t *pos)
__acquires(&nr_list_lock)
{
spin_lock_bh(&nr_list_lock);
return seq_hlist_start_head(&nr_list, *pos);
}
static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_hlist_next(v, &nr_list, pos);
}
static void nr_info_stop(struct seq_file *seq, void *v)
__releases(&nr_list_lock)
{
spin_unlock_bh(&nr_list_lock);
}
static int nr_info_show(struct seq_file *seq, void *v)
{
struct sock *s = sk_entry(v);
struct net_device *dev;
struct nr_sock *nr;
const char *devname;
char buf[11];
if (v == SEQ_START_TOKEN)
seq_puts(seq,
"user_addr dest_node src_node dev my your st vs vr va t1 t2 t4 idle n2 wnd Snd-Q Rcv-Q inode\n");
else {
bh_lock_sock(s);
nr = nr_sk(s);
if ((dev = nr->device) == NULL)
devname = "???";
else
devname = dev->name;
seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
seq_printf(seq,
"%-9s %-3s %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
ax2asc(buf, &nr->source_addr),
devname,
nr->my_index,
nr->my_id,
nr->your_index,
nr->your_id,
nr->state,
nr->vs,
nr->vr,
nr->va,
ax25_display_timer(&nr->t1timer) / HZ,
nr->t1 / HZ,
ax25_display_timer(&nr->t2timer) / HZ,
nr->t2 / HZ,
ax25_display_timer(&nr->t4timer) / HZ,
nr->t4 / HZ,
ax25_display_timer(&nr->idletimer) / (60 * HZ),
nr->idle / (60 * HZ),
nr->n2count,
nr->n2,
nr->window,
sk_wmem_alloc_get(s),
sk_rmem_alloc_get(s),
s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
bh_unlock_sock(s);
}
return 0;
}
static const struct seq_operations nr_info_seqops = {
.start = nr_info_start,
.next = nr_info_next,
.stop = nr_info_stop,
.show = nr_info_show,
};
#endif /* CONFIG_PROC_FS */
static const struct net_proto_family nr_family_ops = {
.family = PF_NETROM,
.create = nr_create,
.owner = THIS_MODULE,
};
static const struct proto_ops nr_proto_ops = {
.family = PF_NETROM,
.owner = THIS_MODULE,
.release = nr_release,
.bind = nr_bind,
.connect = nr_connect,
.socketpair = sock_no_socketpair,
.accept = nr_accept,
.getname = nr_getname,
.poll = datagram_poll,
.ioctl = nr_ioctl,
.gettstamp = sock_gettstamp,
.listen = nr_listen,
.shutdown = sock_no_shutdown,
.setsockopt = nr_setsockopt,
.getsockopt = nr_getsockopt,
.sendmsg = nr_sendmsg,
.recvmsg = nr_recvmsg,
.mmap = sock_no_mmap,
.sendpage = sock_no_sendpage,
};
static struct notifier_block nr_dev_notifier = {
.notifier_call = nr_device_event,
};
static struct net_device **dev_nr;
static struct ax25_protocol nr_pid = {
.pid = AX25_P_NETROM,
.func = nr_route_frame
};
static struct ax25_linkfail nr_linkfail_notifier = {
.func = nr_link_failed,
};
static int __init nr_proto_init(void)
{
int i;
int rc = proto_register(&nr_proto, 0);
if (rc)
return rc;
if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
__func__);
rc = -EINVAL;
goto unregister_proto;
}
dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
if (!dev_nr) {
pr_err("NET/ROM: %s - unable to allocate device array\n",
__func__);
rc = -ENOMEM;
goto unregister_proto;
}
for (i = 0; i < nr_ndevs; i++) {
char name[IFNAMSIZ];
struct net_device *dev;
sprintf(name, "nr%d", i);
dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
if (!dev) {
rc = -ENOMEM;
goto fail;
}
dev->base_addr = i;
rc = register_netdev(dev);
if (rc) {
free_netdev(dev);
goto fail;
}
nr_set_lockdep_key(dev);
dev_nr[i] = dev;
}
rc = sock_register(&nr_family_ops);
if (rc)
goto fail;
rc = register_netdevice_notifier(&nr_dev_notifier);
if (rc)
goto out_sock;
ax25_register_pid(&nr_pid);
ax25_linkfail_register(&nr_linkfail_notifier);
#ifdef CONFIG_SYSCTL
rc = nr_register_sysctl();
if (rc)
goto out_sysctl;
#endif
nr_loopback_init();
rc = -ENOMEM;
if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
goto proc_remove1;
if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
&nr_neigh_seqops))
goto proc_remove2;
if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
&nr_node_seqops))
goto proc_remove3;
return 0;
proc_remove3:
remove_proc_entry("nr_neigh", init_net.proc_net);
proc_remove2:
remove_proc_entry("nr", init_net.proc_net);
proc_remove1:
nr_loopback_clear();
nr_rt_free();
#ifdef CONFIG_SYSCTL
nr_unregister_sysctl();
out_sysctl:
#endif
ax25_linkfail_release(&nr_linkfail_notifier);
ax25_protocol_release(AX25_P_NETROM);
unregister_netdevice_notifier(&nr_dev_notifier);
out_sock:
sock_unregister(PF_NETROM);
fail:
while (--i >= 0) {
unregister_netdev(dev_nr[i]);
free_netdev(dev_nr[i]);
}
kfree(dev_nr);
unregister_proto:
proto_unregister(&nr_proto);
return rc;
}
module_init(nr_proto_init);
module_param(nr_ndevs, int, 0);
MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
MODULE_LICENSE("GPL");
MODULE_ALIAS_NETPROTO(PF_NETROM);
static void __exit nr_exit(void)
{
int i;
remove_proc_entry("nr", init_net.proc_net);
remove_proc_entry("nr_neigh", init_net.proc_net);
remove_proc_entry("nr_nodes", init_net.proc_net);
nr_loopback_clear();
nr_rt_free();
#ifdef CONFIG_SYSCTL
nr_unregister_sysctl();
#endif
ax25_linkfail_release(&nr_linkfail_notifier);
ax25_protocol_release(AX25_P_NETROM);
unregister_netdevice_notifier(&nr_dev_notifier);
sock_unregister(PF_NETROM);
for (i = 0; i < nr_ndevs; i++) {
struct net_device *dev = dev_nr[i];
if (dev) {
unregister_netdev(dev);
free_netdev(dev);
}
}
kfree(dev_nr);
proto_unregister(&nr_proto);
}
module_exit(nr_exit);