diff options
Diffstat (limited to 'net/x25')
| -rw-r--r-- | net/x25/Kconfig | 34 | ||||
| -rw-r--r-- | net/x25/Makefile | 11 | ||||
| -rw-r--r-- | net/x25/af_x25.c | 1856 | ||||
| -rw-r--r-- | net/x25/sysctl_net_x25.c | 88 | ||||
| -rw-r--r-- | net/x25/x25_dev.c | 216 | ||||
| -rw-r--r-- | net/x25/x25_facilities.c | 350 | ||||
| -rw-r--r-- | net/x25/x25_forward.c | 157 | ||||
| -rw-r--r-- | net/x25/x25_in.c | 456 | ||||
| -rw-r--r-- | net/x25/x25_link.c | 421 | ||||
| -rw-r--r-- | net/x25/x25_out.c | 226 | ||||
| -rw-r--r-- | net/x25/x25_proc.c | 206 | ||||
| -rw-r--r-- | net/x25/x25_route.c | 204 | ||||
| -rw-r--r-- | net/x25/x25_subr.c | 384 | ||||
| -rw-r--r-- | net/x25/x25_timer.c | 169 |
14 files changed, 4778 insertions, 0 deletions
diff --git a/net/x25/Kconfig b/net/x25/Kconfig new file mode 100644 index 000000000..68729aa3a --- /dev/null +++ b/net/x25/Kconfig @@ -0,0 +1,34 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# CCITT X.25 Packet Layer +# + +config X25 + tristate "CCITT X.25 Packet Layer" + help + X.25 is a set of standardized network protocols, similar in scope to + frame relay; the one physical line from your box to the X.25 network + entry point can carry several logical point-to-point connections + (called "virtual circuits") to other computers connected to the X.25 + network. Governments, banks, and other organizations tend to use it + to connect to each other or to form Wide Area Networks (WANs). Many + countries have public X.25 networks. X.25 consists of two + protocols: the higher level Packet Layer Protocol (PLP) (say Y here + if you want that) and the lower level data link layer protocol LAPB + (say Y to "LAPB Data Link Driver" below if you want that). + + You can read more about X.25 at <https://www.sangoma.com/tutorials/x25/> and + <http://docwiki.cisco.com/wiki/X.25>. + Information about X.25 for Linux is contained in the files + <file:Documentation/networking/x25.rst> and + <file:Documentation/networking/x25-iface.rst>. + + One connects to an X.25 network either with a dedicated network card + using the X.21 protocol (not yet supported by Linux) or one can do + X.25 over a standard telephone line using an ordinary modem (say Y + to "X.25 async driver" below) or over Ethernet using an ordinary + Ethernet card and the LAPB over Ethernet (say Y to "LAPB Data Link + Driver" and "LAPB over Ethernet driver" below). + + To compile this driver as a module, choose M here: the module + will be called x25. If unsure, say N. diff --git a/net/x25/Makefile b/net/x25/Makefile new file mode 100644 index 000000000..5dd544a23 --- /dev/null +++ b/net/x25/Makefile @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for the Linux X.25 Packet layer. +# + +obj-$(CONFIG_X25) += x25.o + +x25-y := af_x25.o x25_dev.o x25_facilities.o x25_in.o \ + x25_link.o x25_out.o x25_route.o x25_subr.o \ + x25_timer.o x25_proc.o x25_forward.o +x25-$(CONFIG_SYSCTL) += sysctl_net_x25.o diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c new file mode 100644 index 000000000..5c7ad301d --- /dev/null +++ b/net/x25/af_x25.c @@ -0,0 +1,1856 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor Centralised disconnect handling. + * New timer architecture. + * 2000-03-11 Henner Eisen MSG_EOR handling more POSIX compliant. + * 2000-03-22 Daniela Squassoni Allowed disabling/enabling of + * facilities negotiation and increased + * the throughput upper limit. + * 2000-08-27 Arnaldo C. Melo s/suser/capable/ + micro cleanups + * 2000-09-04 Henner Eisen Set sock->state in x25_accept(). + * Fixed x25_output() related skb leakage. + * 2000-10-02 Henner Eisen Made x25_kick() single threaded per socket. + * 2000-10-27 Henner Eisen MSG_DONTWAIT for fragment allocation. + * 2000-11-14 Henner Eisen Closing datalink from NETDEV_GOING_DOWN + * 2002-10-06 Arnaldo C. Melo Get rid of cli/sti, move proc stuff to + * x25_proc.c, using seq_file + * 2005-04-02 Shaun Pereira Selective sub address matching + * with call user data + * 2005-04-15 Shaun Pereira Fast select with no restriction on + * response + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/module.h> +#include <linux/capability.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/sched/signal.h> +#include <linux/timer.h> +#include <linux/string.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <linux/uaccess.h> +#include <linux/fcntl.h> +#include <linux/termios.h> /* For TIOCINQ/OUTQ */ +#include <linux/notifier.h> +#include <linux/init.h> +#include <linux/compat.h> +#include <linux/ctype.h> + +#include <net/x25.h> +#include <net/compat.h> + +int sysctl_x25_restart_request_timeout = X25_DEFAULT_T20; +int sysctl_x25_call_request_timeout = X25_DEFAULT_T21; +int sysctl_x25_reset_request_timeout = X25_DEFAULT_T22; +int sysctl_x25_clear_request_timeout = X25_DEFAULT_T23; +int sysctl_x25_ack_holdback_timeout = X25_DEFAULT_T2; +int sysctl_x25_forward = 0; + +HLIST_HEAD(x25_list); +DEFINE_RWLOCK(x25_list_lock); + +static const struct proto_ops x25_proto_ops; + +static const struct x25_address null_x25_address = {" "}; + +#ifdef CONFIG_COMPAT +struct compat_x25_subscrip_struct { + char device[200-sizeof(compat_ulong_t)]; + compat_ulong_t global_facil_mask; + compat_uint_t extended; +}; +#endif + + +int x25_parse_address_block(struct sk_buff *skb, + struct x25_address *called_addr, + struct x25_address *calling_addr) +{ + unsigned char len; + int needed; + int rc; + + if (!pskb_may_pull(skb, 1)) { + /* packet has no address block */ + rc = 0; + goto empty; + } + + len = *skb->data; + needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2; + + if (!pskb_may_pull(skb, needed)) { + /* packet is too short to hold the addresses it claims + to hold */ + rc = -1; + goto empty; + } + + return x25_addr_ntoa(skb->data, called_addr, calling_addr); + +empty: + *called_addr->x25_addr = 0; + *calling_addr->x25_addr = 0; + + return rc; +} + + +int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr, + struct x25_address *calling_addr) +{ + unsigned int called_len, calling_len; + char *called, *calling; + unsigned int i; + + called_len = (*p >> 0) & 0x0F; + calling_len = (*p >> 4) & 0x0F; + + called = called_addr->x25_addr; + calling = calling_addr->x25_addr; + p++; + + for (i = 0; i < (called_len + calling_len); i++) { + if (i < called_len) { + if (i % 2 != 0) { + *called++ = ((*p >> 0) & 0x0F) + '0'; + p++; + } else { + *called++ = ((*p >> 4) & 0x0F) + '0'; + } + } else { + if (i % 2 != 0) { + *calling++ = ((*p >> 0) & 0x0F) + '0'; + p++; + } else { + *calling++ = ((*p >> 4) & 0x0F) + '0'; + } + } + } + + *called = *calling = '\0'; + + return 1 + (called_len + calling_len + 1) / 2; +} + +int x25_addr_aton(unsigned char *p, struct x25_address *called_addr, + struct x25_address *calling_addr) +{ + unsigned int called_len, calling_len; + char *called, *calling; + int i; + + called = called_addr->x25_addr; + calling = calling_addr->x25_addr; + + called_len = strlen(called); + calling_len = strlen(calling); + + *p++ = (calling_len << 4) | (called_len << 0); + + for (i = 0; i < (called_len + calling_len); i++) { + if (i < called_len) { + if (i % 2 != 0) { + *p |= (*called++ - '0') << 0; + p++; + } else { + *p = 0x00; + *p |= (*called++ - '0') << 4; + } + } else { + if (i % 2 != 0) { + *p |= (*calling++ - '0') << 0; + p++; + } else { + *p = 0x00; + *p |= (*calling++ - '0') << 4; + } + } + } + + return 1 + (called_len + calling_len + 1) / 2; +} + +/* + * Socket removal during an interrupt is now safe. + */ +static void x25_remove_socket(struct sock *sk) +{ + write_lock_bh(&x25_list_lock); + sk_del_node_init(sk); + write_unlock_bh(&x25_list_lock); +} + +/* + * Handle device status changes. + */ +static int x25_device_event(struct notifier_block *this, unsigned long event, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct x25_neigh *nb; + + if (!net_eq(dev_net(dev), &init_net)) + return NOTIFY_DONE; + + if (dev->type == ARPHRD_X25) { + switch (event) { + case NETDEV_REGISTER: + case NETDEV_POST_TYPE_CHANGE: + x25_link_device_up(dev); + break; + case NETDEV_DOWN: + nb = x25_get_neigh(dev); + if (nb) { + x25_link_terminated(nb); + x25_neigh_put(nb); + } + x25_route_device_down(dev); + break; + case NETDEV_PRE_TYPE_CHANGE: + case NETDEV_UNREGISTER: + x25_link_device_down(dev); + break; + case NETDEV_CHANGE: + if (!netif_carrier_ok(dev)) { + nb = x25_get_neigh(dev); + if (nb) { + x25_link_terminated(nb); + x25_neigh_put(nb); + } + } + break; + } + } + + return NOTIFY_DONE; +} + +/* + * Add a socket to the bound sockets list. + */ +static void x25_insert_socket(struct sock *sk) +{ + write_lock_bh(&x25_list_lock); + sk_add_node(sk, &x25_list); + write_unlock_bh(&x25_list_lock); +} + +/* + * Find a socket that wants to accept the Call Request we just + * received. Check the full list for an address/cud match. + * If no cuds match return the next_best thing, an address match. + * Note: if a listening socket has cud set it must only get calls + * with matching cud. + */ +static struct sock *x25_find_listener(struct x25_address *addr, + struct sk_buff *skb) +{ + struct sock *s; + struct sock *next_best; + + read_lock_bh(&x25_list_lock); + next_best = NULL; + + sk_for_each(s, &x25_list) + if ((!strcmp(addr->x25_addr, + x25_sk(s)->source_addr.x25_addr) || + !strcmp(x25_sk(s)->source_addr.x25_addr, + null_x25_address.x25_addr)) && + s->sk_state == TCP_LISTEN) { + /* + * Found a listening socket, now check the incoming + * call user data vs this sockets call user data + */ + if (x25_sk(s)->cudmatchlength > 0 && + skb->len >= x25_sk(s)->cudmatchlength) { + if((memcmp(x25_sk(s)->calluserdata.cuddata, + skb->data, + x25_sk(s)->cudmatchlength)) == 0) { + sock_hold(s); + goto found; + } + } else + next_best = s; + } + if (next_best) { + s = next_best; + sock_hold(s); + goto found; + } + s = NULL; +found: + read_unlock_bh(&x25_list_lock); + return s; +} + +/* + * Find a connected X.25 socket given my LCI and neighbour. + */ +static struct sock *__x25_find_socket(unsigned int lci, struct x25_neigh *nb) +{ + struct sock *s; + + sk_for_each(s, &x25_list) + if (x25_sk(s)->lci == lci && x25_sk(s)->neighbour == nb) { + sock_hold(s); + goto found; + } + s = NULL; +found: + return s; +} + +struct sock *x25_find_socket(unsigned int lci, struct x25_neigh *nb) +{ + struct sock *s; + + read_lock_bh(&x25_list_lock); + s = __x25_find_socket(lci, nb); + read_unlock_bh(&x25_list_lock); + return s; +} + +/* + * Find a unique LCI for a given device. + */ +static unsigned int x25_new_lci(struct x25_neigh *nb) +{ + unsigned int lci = 1; + struct sock *sk; + + while ((sk = x25_find_socket(lci, nb)) != NULL) { + sock_put(sk); + if (++lci == 4096) { + lci = 0; + break; + } + cond_resched(); + } + + return lci; +} + +/* + * Deferred destroy. + */ +static void __x25_destroy_socket(struct sock *); + +/* + * handler for deferred kills. + */ +static void x25_destroy_timer(struct timer_list *t) +{ + struct sock *sk = from_timer(sk, t, sk_timer); + + x25_destroy_socket_from_timer(sk); +} + +/* + * This is called from user mode and the timers. Thus it protects itself + * against interrupting 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. + * Not static as it's used by the timer + */ +static void __x25_destroy_socket(struct sock *sk) +{ + struct sk_buff *skb; + + x25_stop_heartbeat(sk); + x25_stop_timer(sk); + + x25_remove_socket(sk); + x25_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 + */ + skb->sk->sk_state = TCP_LISTEN; + sock_set_flag(skb->sk, SOCK_DEAD); + x25_start_heartbeat(skb->sk); + x25_sk(skb->sk)->state = X25_STATE_0; + } + + kfree_skb(skb); + } + + if (sk_has_allocations(sk)) { + /* Defer: outstanding buffers */ + sk->sk_timer.expires = jiffies + 10 * HZ; + sk->sk_timer.function = x25_destroy_timer; + add_timer(&sk->sk_timer); + } else { + /* drop last reference so sock_put will free */ + __sock_put(sk); + } +} + +void x25_destroy_socket_from_timer(struct sock *sk) +{ + sock_hold(sk); + bh_lock_sock(sk); + __x25_destroy_socket(sk); + bh_unlock_sock(sk); + sock_put(sk); +} + +/* + * Handling for system calls applied via the various interfaces to a + * X.25 socket object. + */ + +static int x25_setsockopt(struct socket *sock, int level, int optname, + sockptr_t optval, unsigned int optlen) +{ + int opt; + struct sock *sk = sock->sk; + int rc = -ENOPROTOOPT; + + if (level != SOL_X25 || optname != X25_QBITINCL) + goto out; + + rc = -EINVAL; + if (optlen < sizeof(int)) + goto out; + + rc = -EFAULT; + if (copy_from_sockptr(&opt, optval, sizeof(int))) + goto out; + + if (opt) + set_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags); + else + clear_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags); + rc = 0; +out: + return rc; +} + +static int x25_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct sock *sk = sock->sk; + int val, len, rc = -ENOPROTOOPT; + + if (level != SOL_X25 || optname != X25_QBITINCL) + goto out; + + rc = -EFAULT; + if (get_user(len, optlen)) + goto out; + + len = min_t(unsigned int, len, sizeof(int)); + + rc = -EINVAL; + if (len < 0) + goto out; + + rc = -EFAULT; + if (put_user(len, optlen)) + goto out; + + val = test_bit(X25_Q_BIT_FLAG, &x25_sk(sk)->flags); + rc = copy_to_user(optval, &val, len) ? -EFAULT : 0; +out: + return rc; +} + +static int x25_listen(struct socket *sock, int backlog) +{ + struct sock *sk = sock->sk; + int rc = -EOPNOTSUPP; + + lock_sock(sk); + if (sock->state != SS_UNCONNECTED) { + rc = -EINVAL; + release_sock(sk); + return rc; + } + + if (sk->sk_state != TCP_LISTEN) { + memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN); + sk->sk_max_ack_backlog = backlog; + sk->sk_state = TCP_LISTEN; + rc = 0; + } + release_sock(sk); + + return rc; +} + +static struct proto x25_proto = { + .name = "X25", + .owner = THIS_MODULE, + .obj_size = sizeof(struct x25_sock), +}; + +static struct sock *x25_alloc_socket(struct net *net, int kern) +{ + struct x25_sock *x25; + struct sock *sk = sk_alloc(net, AF_X25, GFP_ATOMIC, &x25_proto, kern); + + if (!sk) + goto out; + + sock_init_data(NULL, sk); + + x25 = x25_sk(sk); + skb_queue_head_init(&x25->ack_queue); + skb_queue_head_init(&x25->fragment_queue); + skb_queue_head_init(&x25->interrupt_in_queue); + skb_queue_head_init(&x25->interrupt_out_queue); +out: + return sk; +} + +static int x25_create(struct net *net, struct socket *sock, int protocol, + int kern) +{ + struct sock *sk; + struct x25_sock *x25; + int rc = -EAFNOSUPPORT; + + if (!net_eq(net, &init_net)) + goto out; + + rc = -ESOCKTNOSUPPORT; + if (sock->type != SOCK_SEQPACKET) + goto out; + + rc = -EINVAL; + if (protocol) + goto out; + + rc = -ENOMEM; + if ((sk = x25_alloc_socket(net, kern)) == NULL) + goto out; + + x25 = x25_sk(sk); + + sock_init_data(sock, sk); + + x25_init_timers(sk); + + sock->ops = &x25_proto_ops; + sk->sk_protocol = protocol; + sk->sk_backlog_rcv = x25_backlog_rcv; + + x25->t21 = sysctl_x25_call_request_timeout; + x25->t22 = sysctl_x25_reset_request_timeout; + x25->t23 = sysctl_x25_clear_request_timeout; + x25->t2 = sysctl_x25_ack_holdback_timeout; + x25->state = X25_STATE_0; + x25->cudmatchlength = 0; + set_bit(X25_ACCPT_APPRV_FLAG, &x25->flags); /* normally no cud */ + /* on call accept */ + + x25->facilities.winsize_in = X25_DEFAULT_WINDOW_SIZE; + x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE; + x25->facilities.pacsize_in = X25_DEFAULT_PACKET_SIZE; + x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE; + x25->facilities.throughput = 0; /* by default don't negotiate + throughput */ + x25->facilities.reverse = X25_DEFAULT_REVERSE; + x25->dte_facilities.calling_len = 0; + x25->dte_facilities.called_len = 0; + memset(x25->dte_facilities.called_ae, '\0', + sizeof(x25->dte_facilities.called_ae)); + memset(x25->dte_facilities.calling_ae, '\0', + sizeof(x25->dte_facilities.calling_ae)); + + rc = 0; +out: + return rc; +} + +static struct sock *x25_make_new(struct sock *osk) +{ + struct sock *sk = NULL; + struct x25_sock *x25, *ox25; + + if (osk->sk_type != SOCK_SEQPACKET) + goto out; + + if ((sk = x25_alloc_socket(sock_net(osk), 0)) == NULL) + goto out; + + x25 = x25_sk(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; + sk->sk_backlog_rcv = osk->sk_backlog_rcv; + sock_copy_flags(sk, osk); + + ox25 = x25_sk(osk); + x25->t21 = ox25->t21; + x25->t22 = ox25->t22; + x25->t23 = ox25->t23; + x25->t2 = ox25->t2; + x25->flags = ox25->flags; + x25->facilities = ox25->facilities; + x25->dte_facilities = ox25->dte_facilities; + x25->cudmatchlength = ox25->cudmatchlength; + + clear_bit(X25_INTERRUPT_FLAG, &x25->flags); + x25_init_timers(sk); +out: + return sk; +} + +static int x25_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct x25_sock *x25; + + if (!sk) + return 0; + + x25 = x25_sk(sk); + + sock_hold(sk); + lock_sock(sk); + switch (x25->state) { + + case X25_STATE_0: + case X25_STATE_2: + x25_disconnect(sk, 0, 0, 0); + __x25_destroy_socket(sk); + goto out; + + case X25_STATE_1: + case X25_STATE_3: + case X25_STATE_4: + x25_clear_queues(sk); + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25_start_t23timer(sk); + x25->state = X25_STATE_2; + sk->sk_state = TCP_CLOSE; + sk->sk_shutdown |= SEND_SHUTDOWN; + sk->sk_state_change(sk); + sock_set_flag(sk, SOCK_DEAD); + sock_set_flag(sk, SOCK_DESTROY); + break; + + case X25_STATE_5: + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25_disconnect(sk, 0, 0, 0); + __x25_destroy_socket(sk); + goto out; + } + + sock_orphan(sk); +out: + release_sock(sk); + sock_put(sk); + return 0; +} + +static int x25_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) +{ + struct sock *sk = sock->sk; + struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr; + int len, i, rc = 0; + + if (addr_len != sizeof(struct sockaddr_x25) || + addr->sx25_family != AF_X25 || + strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) { + rc = -EINVAL; + goto out; + } + + /* check for the null_x25_address */ + if (strcmp(addr->sx25_addr.x25_addr, null_x25_address.x25_addr)) { + + len = strlen(addr->sx25_addr.x25_addr); + for (i = 0; i < len; i++) { + if (!isdigit(addr->sx25_addr.x25_addr[i])) { + rc = -EINVAL; + goto out; + } + } + } + + lock_sock(sk); + if (sock_flag(sk, SOCK_ZAPPED)) { + x25_sk(sk)->source_addr = addr->sx25_addr; + x25_insert_socket(sk); + sock_reset_flag(sk, SOCK_ZAPPED); + } else { + rc = -EINVAL; + } + release_sock(sk); + SOCK_DEBUG(sk, "x25_bind: socket is bound\n"); +out: + return rc; +} + +static int x25_wait_for_connection_establishment(struct sock *sk) +{ + DECLARE_WAITQUEUE(wait, current); + int rc; + + add_wait_queue_exclusive(sk_sleep(sk), &wait); + for (;;) { + __set_current_state(TASK_INTERRUPTIBLE); + rc = -ERESTARTSYS; + if (signal_pending(current)) + break; + rc = sock_error(sk); + if (rc) { + sk->sk_socket->state = SS_UNCONNECTED; + break; + } + rc = -ENOTCONN; + if (sk->sk_state == TCP_CLOSE) { + sk->sk_socket->state = SS_UNCONNECTED; + break; + } + rc = 0; + if (sk->sk_state != TCP_ESTABLISHED) { + release_sock(sk); + schedule(); + lock_sock(sk); + } else + break; + } + __set_current_state(TASK_RUNNING); + remove_wait_queue(sk_sleep(sk), &wait); + return rc; +} + +static int x25_connect(struct socket *sock, struct sockaddr *uaddr, + int addr_len, int flags) +{ + struct sock *sk = sock->sk; + struct x25_sock *x25 = x25_sk(sk); + struct sockaddr_x25 *addr = (struct sockaddr_x25 *)uaddr; + struct x25_route *rt; + int rc = 0; + + lock_sock(sk); + if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) { + sock->state = SS_CONNECTED; + goto out; /* Connect completed during a ERESTARTSYS event */ + } + + rc = -ECONNREFUSED; + if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) { + sock->state = SS_UNCONNECTED; + goto out; + } + + rc = -EISCONN; /* No reconnect on a seqpacket socket */ + if (sk->sk_state == TCP_ESTABLISHED) + goto out; + + rc = -EALREADY; /* Do nothing if call is already in progress */ + if (sk->sk_state == TCP_SYN_SENT) + goto out; + + sk->sk_state = TCP_CLOSE; + sock->state = SS_UNCONNECTED; + + rc = -EINVAL; + if (addr_len != sizeof(struct sockaddr_x25) || + addr->sx25_family != AF_X25 || + strnlen(addr->sx25_addr.x25_addr, X25_ADDR_LEN) == X25_ADDR_LEN) + goto out; + + rc = -ENETUNREACH; + rt = x25_get_route(&addr->sx25_addr); + if (!rt) + goto out; + + x25->neighbour = x25_get_neigh(rt->dev); + if (!x25->neighbour) + goto out_put_route; + + x25_limit_facilities(&x25->facilities, x25->neighbour); + + x25->lci = x25_new_lci(x25->neighbour); + if (!x25->lci) + goto out_put_neigh; + + rc = -EINVAL; + if (sock_flag(sk, SOCK_ZAPPED)) /* Must bind first - autobinding does not work */ + goto out_put_neigh; + + if (!strcmp(x25->source_addr.x25_addr, null_x25_address.x25_addr)) + memset(&x25->source_addr, '\0', X25_ADDR_LEN); + + x25->dest_addr = addr->sx25_addr; + + /* Move to connecting socket, start sending Connect Requests */ + sock->state = SS_CONNECTING; + sk->sk_state = TCP_SYN_SENT; + + x25->state = X25_STATE_1; + + x25_write_internal(sk, X25_CALL_REQUEST); + + x25_start_heartbeat(sk); + x25_start_t21timer(sk); + + /* Now the loop */ + rc = -EINPROGRESS; + if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) + goto out; + + rc = x25_wait_for_connection_establishment(sk); + if (rc) + goto out_put_neigh; + + sock->state = SS_CONNECTED; + rc = 0; +out_put_neigh: + if (rc && x25->neighbour) { + read_lock_bh(&x25_list_lock); + x25_neigh_put(x25->neighbour); + x25->neighbour = NULL; + read_unlock_bh(&x25_list_lock); + x25->state = X25_STATE_0; + } +out_put_route: + x25_route_put(rt); +out: + release_sock(sk); + return rc; +} + +static int x25_wait_for_data(struct sock *sk, long timeout) +{ + DECLARE_WAITQUEUE(wait, current); + int rc = 0; + + add_wait_queue_exclusive(sk_sleep(sk), &wait); + for (;;) { + __set_current_state(TASK_INTERRUPTIBLE); + if (sk->sk_shutdown & RCV_SHUTDOWN) + break; + rc = -ERESTARTSYS; + if (signal_pending(current)) + break; + rc = -EAGAIN; + if (!timeout) + break; + rc = 0; + if (skb_queue_empty(&sk->sk_receive_queue)) { + release_sock(sk); + timeout = schedule_timeout(timeout); + lock_sock(sk); + } else + break; + } + __set_current_state(TASK_RUNNING); + remove_wait_queue(sk_sleep(sk), &wait); + return rc; +} + +static int x25_accept(struct socket *sock, struct socket *newsock, int flags, + bool kern) +{ + struct sock *sk = sock->sk; + struct sock *newsk; + struct sk_buff *skb; + int rc = -EINVAL; + + if (!sk) + goto out; + + rc = -EOPNOTSUPP; + if (sk->sk_type != SOCK_SEQPACKET) + goto out; + + lock_sock(sk); + rc = -EINVAL; + if (sk->sk_state != TCP_LISTEN) + goto out2; + + rc = x25_wait_for_data(sk, sk->sk_rcvtimeo); + if (rc) + goto out2; + skb = skb_dequeue(&sk->sk_receive_queue); + rc = -EINVAL; + if (!skb->sk) + goto out2; + newsk = skb->sk; + sock_graft(newsk, newsock); + + /* Now attach up the new socket */ + skb->sk = NULL; + kfree_skb(skb); + sk_acceptq_removed(sk); + newsock->state = SS_CONNECTED; + rc = 0; +out2: + release_sock(sk); +out: + return rc; +} + +static int x25_getname(struct socket *sock, struct sockaddr *uaddr, + int peer) +{ + struct sockaddr_x25 *sx25 = (struct sockaddr_x25 *)uaddr; + struct sock *sk = sock->sk; + struct x25_sock *x25 = x25_sk(sk); + int rc = 0; + + if (peer) { + if (sk->sk_state != TCP_ESTABLISHED) { + rc = -ENOTCONN; + goto out; + } + sx25->sx25_addr = x25->dest_addr; + } else + sx25->sx25_addr = x25->source_addr; + + sx25->sx25_family = AF_X25; + rc = sizeof(*sx25); + +out: + return rc; +} + +int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb, + unsigned int lci) +{ + struct sock *sk; + struct sock *make; + struct x25_sock *makex25; + struct x25_address source_addr, dest_addr; + struct x25_facilities facilities; + struct x25_dte_facilities dte_facilities; + int len, addr_len, rc; + + /* + * Remove the LCI and frame type. + */ + skb_pull(skb, X25_STD_MIN_LEN); + + /* + * Extract the X.25 addresses and convert them to ASCII strings, + * and remove them. + * + * Address block is mandatory in call request packets + */ + addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr); + if (addr_len <= 0) + goto out_clear_request; + skb_pull(skb, addr_len); + + /* + * Get the length of the facilities, skip past them for the moment + * get the call user data because this is needed to determine + * the correct listener + * + * Facilities length is mandatory in call request packets + */ + if (!pskb_may_pull(skb, 1)) + goto out_clear_request; + len = skb->data[0] + 1; + if (!pskb_may_pull(skb, len)) + goto out_clear_request; + skb_pull(skb,len); + + /* + * Ensure that the amount of call user data is valid. + */ + if (skb->len > X25_MAX_CUD_LEN) + goto out_clear_request; + + /* + * Get all the call user data so it can be used in + * x25_find_listener and skb_copy_from_linear_data up ahead. + */ + if (!pskb_may_pull(skb, skb->len)) + goto out_clear_request; + + /* + * Find a listener for the particular address/cud pair. + */ + sk = x25_find_listener(&source_addr,skb); + skb_push(skb,len); + + if (sk != NULL && sk_acceptq_is_full(sk)) { + goto out_sock_put; + } + + /* + * We dont have any listeners for this incoming call. + * Try forwarding it. + */ + if (sk == NULL) { + skb_push(skb, addr_len + X25_STD_MIN_LEN); + if (sysctl_x25_forward && + x25_forward_call(&dest_addr, nb, skb, lci) > 0) + { + /* Call was forwarded, dont process it any more */ + kfree_skb(skb); + rc = 1; + goto out; + } else { + /* No listeners, can't forward, clear the call */ + goto out_clear_request; + } + } + + /* + * Try to reach a compromise on the requested facilities. + */ + len = x25_negotiate_facilities(skb, sk, &facilities, &dte_facilities); + if (len == -1) + goto out_sock_put; + + /* + * current neighbour/link might impose additional limits + * on certain facilities + */ + + x25_limit_facilities(&facilities, nb); + + /* + * Try to create a new socket. + */ + make = x25_make_new(sk); + if (!make) + goto out_sock_put; + + /* + * Remove the facilities + */ + skb_pull(skb, len); + + skb->sk = make; + make->sk_state = TCP_ESTABLISHED; + + makex25 = x25_sk(make); + makex25->lci = lci; + makex25->dest_addr = dest_addr; + makex25->source_addr = source_addr; + x25_neigh_hold(nb); + makex25->neighbour = nb; + makex25->facilities = facilities; + makex25->dte_facilities= dte_facilities; + makex25->vc_facil_mask = x25_sk(sk)->vc_facil_mask; + /* ensure no reverse facil on accept */ + makex25->vc_facil_mask &= ~X25_MASK_REVERSE; + /* ensure no calling address extension on accept */ + makex25->vc_facil_mask &= ~X25_MASK_CALLING_AE; + makex25->cudmatchlength = x25_sk(sk)->cudmatchlength; + + /* Normally all calls are accepted immediately */ + if (test_bit(X25_ACCPT_APPRV_FLAG, &makex25->flags)) { + x25_write_internal(make, X25_CALL_ACCEPTED); + makex25->state = X25_STATE_3; + } else { + makex25->state = X25_STATE_5; + } + + /* + * Incoming Call User Data. + */ + skb_copy_from_linear_data(skb, makex25->calluserdata.cuddata, skb->len); + makex25->calluserdata.cudlength = skb->len; + + sk_acceptq_added(sk); + + x25_insert_socket(make); + + skb_queue_head(&sk->sk_receive_queue, skb); + + x25_start_heartbeat(make); + + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk); + rc = 1; + sock_put(sk); +out: + return rc; +out_sock_put: + sock_put(sk); +out_clear_request: + rc = 0; + x25_transmit_clear_request(nb, lci, 0x01); + goto out; +} + +static int x25_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) +{ + struct sock *sk = sock->sk; + struct x25_sock *x25 = x25_sk(sk); + DECLARE_SOCKADDR(struct sockaddr_x25 *, usx25, msg->msg_name); + struct sockaddr_x25 sx25; + struct sk_buff *skb; + unsigned char *asmptr; + int noblock = msg->msg_flags & MSG_DONTWAIT; + size_t size; + int qbit = 0, rc = -EINVAL; + + lock_sock(sk); + if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_OOB|MSG_EOR|MSG_CMSG_COMPAT)) + goto out; + + /* we currently don't support segmented records at the user interface */ + if (!(msg->msg_flags & (MSG_EOR|MSG_OOB))) + goto out; + + rc = -EADDRNOTAVAIL; + if (sock_flag(sk, SOCK_ZAPPED)) + goto out; + + rc = -EPIPE; + if (sk->sk_shutdown & SEND_SHUTDOWN) { + send_sig(SIGPIPE, current, 0); + goto out; + } + + rc = -ENETUNREACH; + if (!x25->neighbour) + goto out; + + if (usx25) { + rc = -EINVAL; + if (msg->msg_namelen < sizeof(sx25)) + goto out; + memcpy(&sx25, usx25, sizeof(sx25)); + rc = -EISCONN; + if (strcmp(x25->dest_addr.x25_addr, sx25.sx25_addr.x25_addr)) + goto out; + rc = -EINVAL; + if (sx25.sx25_family != AF_X25) + goto out; + } else { + /* + * FIXME 1003.1g - if the socket is like this because + * it has become closed (not started closed) we ought + * to SIGPIPE, EPIPE; + */ + rc = -ENOTCONN; + if (sk->sk_state != TCP_ESTABLISHED) + goto out; + + sx25.sx25_family = AF_X25; + sx25.sx25_addr = x25->dest_addr; + } + + /* Sanity check the packet size */ + if (len > 65535) { + rc = -EMSGSIZE; + goto out; + } + + SOCK_DEBUG(sk, "x25_sendmsg: sendto: Addresses built.\n"); + + /* Build a packet */ + SOCK_DEBUG(sk, "x25_sendmsg: sendto: building packet.\n"); + + if ((msg->msg_flags & MSG_OOB) && len > 32) + len = 32; + + size = len + X25_MAX_L2_LEN + X25_EXT_MIN_LEN; + + release_sock(sk); + skb = sock_alloc_send_skb(sk, size, noblock, &rc); + lock_sock(sk); + if (!skb) + goto out; + X25_SKB_CB(skb)->flags = msg->msg_flags; + + skb_reserve(skb, X25_MAX_L2_LEN + X25_EXT_MIN_LEN); + + /* + * Put the data on the end + */ + SOCK_DEBUG(sk, "x25_sendmsg: Copying user data\n"); + + skb_reset_transport_header(skb); + skb_put(skb, len); + + rc = memcpy_from_msg(skb_transport_header(skb), msg, len); + if (rc) + goto out_kfree_skb; + + /* + * If the Q BIT Include socket option is in force, the first + * byte of the user data is the logical value of the Q Bit. + */ + if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) { + if (!pskb_may_pull(skb, 1)) + goto out_kfree_skb; + + qbit = skb->data[0]; + skb_pull(skb, 1); + } + + /* + * Push down the X.25 header + */ + SOCK_DEBUG(sk, "x25_sendmsg: Building X.25 Header.\n"); + + if (msg->msg_flags & MSG_OOB) { + if (x25->neighbour->extended) { + asmptr = skb_push(skb, X25_STD_MIN_LEN); + *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ; + *asmptr++ = (x25->lci >> 0) & 0xFF; + *asmptr++ = X25_INTERRUPT; + } else { + asmptr = skb_push(skb, X25_STD_MIN_LEN); + *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ; + *asmptr++ = (x25->lci >> 0) & 0xFF; + *asmptr++ = X25_INTERRUPT; + } + } else { + if (x25->neighbour->extended) { + /* Build an Extended X.25 header */ + asmptr = skb_push(skb, X25_EXT_MIN_LEN); + *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_EXTSEQ; + *asmptr++ = (x25->lci >> 0) & 0xFF; + *asmptr++ = X25_DATA; + *asmptr++ = X25_DATA; + } else { + /* Build an Standard X.25 header */ + asmptr = skb_push(skb, X25_STD_MIN_LEN); + *asmptr++ = ((x25->lci >> 8) & 0x0F) | X25_GFI_STDSEQ; + *asmptr++ = (x25->lci >> 0) & 0xFF; + *asmptr++ = X25_DATA; + } + + if (qbit) + skb->data[0] |= X25_Q_BIT; + } + + SOCK_DEBUG(sk, "x25_sendmsg: Built header.\n"); + SOCK_DEBUG(sk, "x25_sendmsg: Transmitting buffer\n"); + + rc = -ENOTCONN; + if (sk->sk_state != TCP_ESTABLISHED) + goto out_kfree_skb; + + if (msg->msg_flags & MSG_OOB) + skb_queue_tail(&x25->interrupt_out_queue, skb); + else { + rc = x25_output(sk, skb); + len = rc; + if (rc < 0) + kfree_skb(skb); + else if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) + len++; + } + + x25_kick(sk); + rc = len; +out: + release_sock(sk); + return rc; +out_kfree_skb: + kfree_skb(skb); + goto out; +} + + +static int x25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, + int flags) +{ + struct sock *sk = sock->sk; + struct x25_sock *x25 = x25_sk(sk); + DECLARE_SOCKADDR(struct sockaddr_x25 *, sx25, msg->msg_name); + size_t copied; + int qbit, header_len; + struct sk_buff *skb; + unsigned char *asmptr; + int rc = -ENOTCONN; + + lock_sock(sk); + + if (x25->neighbour == NULL) + goto out; + + header_len = x25->neighbour->extended ? + X25_EXT_MIN_LEN : X25_STD_MIN_LEN; + + /* + * This works for seqpacket too. The receiver has ordered the queue for + * us! We do one quick check first though + */ + if (sk->sk_state != TCP_ESTABLISHED) + goto out; + + if (flags & MSG_OOB) { + rc = -EINVAL; + if (sock_flag(sk, SOCK_URGINLINE) || + !skb_peek(&x25->interrupt_in_queue)) + goto out; + + skb = skb_dequeue(&x25->interrupt_in_queue); + + if (!pskb_may_pull(skb, X25_STD_MIN_LEN)) + goto out_free_dgram; + + skb_pull(skb, X25_STD_MIN_LEN); + + /* + * No Q bit information on Interrupt data. + */ + if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) { + asmptr = skb_push(skb, 1); + *asmptr = 0x00; + } + + msg->msg_flags |= MSG_OOB; + } else { + /* Now we can treat all alike */ + release_sock(sk); + skb = skb_recv_datagram(sk, flags, &rc); + lock_sock(sk); + if (!skb) + goto out; + + if (!pskb_may_pull(skb, header_len)) + goto out_free_dgram; + + qbit = (skb->data[0] & X25_Q_BIT) == X25_Q_BIT; + + skb_pull(skb, header_len); + + if (test_bit(X25_Q_BIT_FLAG, &x25->flags)) { + asmptr = skb_push(skb, 1); + *asmptr = qbit; + } + } + + skb_reset_transport_header(skb); + copied = skb->len; + + if (copied > size) { + copied = size; + msg->msg_flags |= MSG_TRUNC; + } + + /* Currently, each datagram always contains a complete record */ + msg->msg_flags |= MSG_EOR; + + rc = skb_copy_datagram_msg(skb, 0, msg, copied); + if (rc) + goto out_free_dgram; + + if (sx25) { + sx25->sx25_family = AF_X25; + sx25->sx25_addr = x25->dest_addr; + msg->msg_namelen = sizeof(*sx25); + } + + x25_check_rbuf(sk); + rc = copied; +out_free_dgram: + skb_free_datagram(sk, skb); +out: + release_sock(sk); + return rc; +} + + +static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) +{ + struct sock *sk = sock->sk; + struct x25_sock *x25 = x25_sk(sk); + void __user *argp = (void __user *)arg; + int rc; + + switch (cmd) { + case TIOCOUTQ: { + int amount; + + amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk); + if (amount < 0) + amount = 0; + rc = put_user(amount, (unsigned int __user *)argp); + break; + } + + case TIOCINQ: { + struct sk_buff *skb; + int amount = 0; + /* + * These two are safe on a single CPU system as + * only user tasks fiddle here + */ + lock_sock(sk); + if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) + amount = skb->len; + release_sock(sk); + rc = put_user(amount, (unsigned int __user *)argp); + break; + } + + case SIOCGIFADDR: + case SIOCSIFADDR: + case SIOCGIFDSTADDR: + case SIOCSIFDSTADDR: + case SIOCGIFBRDADDR: + case SIOCSIFBRDADDR: + case SIOCGIFNETMASK: + case SIOCSIFNETMASK: + case SIOCGIFMETRIC: + case SIOCSIFMETRIC: + rc = -EINVAL; + break; + case SIOCADDRT: + case SIOCDELRT: + rc = -EPERM; + if (!capable(CAP_NET_ADMIN)) + break; + rc = x25_route_ioctl(cmd, argp); + break; + case SIOCX25GSUBSCRIP: + rc = x25_subscr_ioctl(cmd, argp); + break; + case SIOCX25SSUBSCRIP: + rc = -EPERM; + if (!capable(CAP_NET_ADMIN)) + break; + rc = x25_subscr_ioctl(cmd, argp); + break; + case SIOCX25GFACILITIES: { + lock_sock(sk); + rc = copy_to_user(argp, &x25->facilities, + sizeof(x25->facilities)) + ? -EFAULT : 0; + release_sock(sk); + break; + } + + case SIOCX25SFACILITIES: { + struct x25_facilities facilities; + rc = -EFAULT; + if (copy_from_user(&facilities, argp, sizeof(facilities))) + break; + rc = -EINVAL; + lock_sock(sk); + if (sk->sk_state != TCP_LISTEN && + sk->sk_state != TCP_CLOSE) + goto out_fac_release; + if (facilities.pacsize_in < X25_PS16 || + facilities.pacsize_in > X25_PS4096) + goto out_fac_release; + if (facilities.pacsize_out < X25_PS16 || + facilities.pacsize_out > X25_PS4096) + goto out_fac_release; + if (facilities.winsize_in < 1 || + facilities.winsize_in > 127) + goto out_fac_release; + if (facilities.throughput) { + int out = facilities.throughput & 0xf0; + int in = facilities.throughput & 0x0f; + if (!out) + facilities.throughput |= + X25_DEFAULT_THROUGHPUT << 4; + else if (out < 0x30 || out > 0xD0) + goto out_fac_release; + if (!in) + facilities.throughput |= + X25_DEFAULT_THROUGHPUT; + else if (in < 0x03 || in > 0x0D) + goto out_fac_release; + } + if (facilities.reverse && + (facilities.reverse & 0x81) != 0x81) + goto out_fac_release; + x25->facilities = facilities; + rc = 0; +out_fac_release: + release_sock(sk); + break; + } + + case SIOCX25GDTEFACILITIES: { + lock_sock(sk); + rc = copy_to_user(argp, &x25->dte_facilities, + sizeof(x25->dte_facilities)); + release_sock(sk); + if (rc) + rc = -EFAULT; + break; + } + + case SIOCX25SDTEFACILITIES: { + struct x25_dte_facilities dtefacs; + rc = -EFAULT; + if (copy_from_user(&dtefacs, argp, sizeof(dtefacs))) + break; + rc = -EINVAL; + lock_sock(sk); + if (sk->sk_state != TCP_LISTEN && + sk->sk_state != TCP_CLOSE) + goto out_dtefac_release; + if (dtefacs.calling_len > X25_MAX_AE_LEN) + goto out_dtefac_release; + if (dtefacs.called_len > X25_MAX_AE_LEN) + goto out_dtefac_release; + x25->dte_facilities = dtefacs; + rc = 0; +out_dtefac_release: + release_sock(sk); + break; + } + + case SIOCX25GCALLUSERDATA: { + lock_sock(sk); + rc = copy_to_user(argp, &x25->calluserdata, + sizeof(x25->calluserdata)) + ? -EFAULT : 0; + release_sock(sk); + break; + } + + case SIOCX25SCALLUSERDATA: { + struct x25_calluserdata calluserdata; + + rc = -EFAULT; + if (copy_from_user(&calluserdata, argp, sizeof(calluserdata))) + break; + rc = -EINVAL; + if (calluserdata.cudlength > X25_MAX_CUD_LEN) + break; + lock_sock(sk); + x25->calluserdata = calluserdata; + release_sock(sk); + rc = 0; + break; + } + + case SIOCX25GCAUSEDIAG: { + lock_sock(sk); + rc = copy_to_user(argp, &x25->causediag, sizeof(x25->causediag)) + ? -EFAULT : 0; + release_sock(sk); + break; + } + + case SIOCX25SCAUSEDIAG: { + struct x25_causediag causediag; + rc = -EFAULT; + if (copy_from_user(&causediag, argp, sizeof(causediag))) + break; + lock_sock(sk); + x25->causediag = causediag; + release_sock(sk); + rc = 0; + break; + + } + + case SIOCX25SCUDMATCHLEN: { + struct x25_subaddr sub_addr; + rc = -EINVAL; + lock_sock(sk); + if(sk->sk_state != TCP_CLOSE) + goto out_cud_release; + rc = -EFAULT; + if (copy_from_user(&sub_addr, argp, + sizeof(sub_addr))) + goto out_cud_release; + rc = -EINVAL; + if (sub_addr.cudmatchlength > X25_MAX_CUD_LEN) + goto out_cud_release; + x25->cudmatchlength = sub_addr.cudmatchlength; + rc = 0; +out_cud_release: + release_sock(sk); + break; + } + + case SIOCX25CALLACCPTAPPRV: { + rc = -EINVAL; + lock_sock(sk); + if (sk->sk_state == TCP_CLOSE) { + clear_bit(X25_ACCPT_APPRV_FLAG, &x25->flags); + rc = 0; + } + release_sock(sk); + break; + } + + case SIOCX25SENDCALLACCPT: { + rc = -EINVAL; + lock_sock(sk); + if (sk->sk_state != TCP_ESTABLISHED) + goto out_sendcallaccpt_release; + /* must call accptapprv above */ + if (test_bit(X25_ACCPT_APPRV_FLAG, &x25->flags)) + goto out_sendcallaccpt_release; + x25_write_internal(sk, X25_CALL_ACCEPTED); + x25->state = X25_STATE_3; + rc = 0; +out_sendcallaccpt_release: + release_sock(sk); + break; + } + + default: + rc = -ENOIOCTLCMD; + break; + } + + return rc; +} + +static const struct net_proto_family x25_family_ops = { + .family = AF_X25, + .create = x25_create, + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_COMPAT +static int compat_x25_subscr_ioctl(unsigned int cmd, + struct compat_x25_subscrip_struct __user *x25_subscr32) +{ + struct compat_x25_subscrip_struct x25_subscr; + struct x25_neigh *nb; + struct net_device *dev; + int rc = -EINVAL; + + rc = -EFAULT; + if (copy_from_user(&x25_subscr, x25_subscr32, sizeof(*x25_subscr32))) + goto out; + + rc = -EINVAL; + dev = x25_dev_get(x25_subscr.device); + if (dev == NULL) + goto out; + + nb = x25_get_neigh(dev); + if (nb == NULL) + goto out_dev_put; + + dev_put(dev); + + if (cmd == SIOCX25GSUBSCRIP) { + read_lock_bh(&x25_neigh_list_lock); + x25_subscr.extended = nb->extended; + x25_subscr.global_facil_mask = nb->global_facil_mask; + read_unlock_bh(&x25_neigh_list_lock); + rc = copy_to_user(x25_subscr32, &x25_subscr, + sizeof(*x25_subscr32)) ? -EFAULT : 0; + } else { + rc = -EINVAL; + if (x25_subscr.extended == 0 || x25_subscr.extended == 1) { + rc = 0; + write_lock_bh(&x25_neigh_list_lock); + nb->extended = x25_subscr.extended; + nb->global_facil_mask = x25_subscr.global_facil_mask; + write_unlock_bh(&x25_neigh_list_lock); + } + } + x25_neigh_put(nb); +out: + return rc; +out_dev_put: + dev_put(dev); + goto out; +} + +static int compat_x25_ioctl(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + void __user *argp = compat_ptr(arg); + int rc = -ENOIOCTLCMD; + + switch(cmd) { + case TIOCOUTQ: + case TIOCINQ: + rc = x25_ioctl(sock, cmd, (unsigned long)argp); + break; + case SIOCGIFADDR: + case SIOCSIFADDR: + case SIOCGIFDSTADDR: + case SIOCSIFDSTADDR: + case SIOCGIFBRDADDR: + case SIOCSIFBRDADDR: + case SIOCGIFNETMASK: + case SIOCSIFNETMASK: + case SIOCGIFMETRIC: + case SIOCSIFMETRIC: + rc = -EINVAL; + break; + case SIOCADDRT: + case SIOCDELRT: + rc = -EPERM; + if (!capable(CAP_NET_ADMIN)) + break; + rc = x25_route_ioctl(cmd, argp); + break; + case SIOCX25GSUBSCRIP: + rc = compat_x25_subscr_ioctl(cmd, argp); + break; + case SIOCX25SSUBSCRIP: + rc = -EPERM; + if (!capable(CAP_NET_ADMIN)) + break; + rc = compat_x25_subscr_ioctl(cmd, argp); + break; + case SIOCX25GFACILITIES: + case SIOCX25SFACILITIES: + case SIOCX25GDTEFACILITIES: + case SIOCX25SDTEFACILITIES: + case SIOCX25GCALLUSERDATA: + case SIOCX25SCALLUSERDATA: + case SIOCX25GCAUSEDIAG: + case SIOCX25SCAUSEDIAG: + case SIOCX25SCUDMATCHLEN: + case SIOCX25CALLACCPTAPPRV: + case SIOCX25SENDCALLACCPT: + rc = x25_ioctl(sock, cmd, (unsigned long)argp); + break; + default: + rc = -ENOIOCTLCMD; + break; + } + return rc; +} +#endif + +static const struct proto_ops x25_proto_ops = { + .family = AF_X25, + .owner = THIS_MODULE, + .release = x25_release, + .bind = x25_bind, + .connect = x25_connect, + .socketpair = sock_no_socketpair, + .accept = x25_accept, + .getname = x25_getname, + .poll = datagram_poll, + .ioctl = x25_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = compat_x25_ioctl, +#endif + .gettstamp = sock_gettstamp, + .listen = x25_listen, + .shutdown = sock_no_shutdown, + .setsockopt = x25_setsockopt, + .getsockopt = x25_getsockopt, + .sendmsg = x25_sendmsg, + .recvmsg = x25_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +static struct packet_type x25_packet_type __read_mostly = { + .type = cpu_to_be16(ETH_P_X25), + .func = x25_lapb_receive_frame, +}; + +static struct notifier_block x25_dev_notifier = { + .notifier_call = x25_device_event, +}; + +void x25_kill_by_neigh(struct x25_neigh *nb) +{ + struct sock *s; + + write_lock_bh(&x25_list_lock); + + sk_for_each(s, &x25_list) { + if (x25_sk(s)->neighbour == nb) { + write_unlock_bh(&x25_list_lock); + lock_sock(s); + x25_disconnect(s, ENETUNREACH, 0, 0); + release_sock(s); + write_lock_bh(&x25_list_lock); + } + } + write_unlock_bh(&x25_list_lock); + + /* Remove any related forwards */ + x25_clear_forward_by_dev(nb->dev); +} + +static int __init x25_init(void) +{ + int rc; + + rc = proto_register(&x25_proto, 0); + if (rc) + goto out; + + rc = sock_register(&x25_family_ops); + if (rc) + goto out_proto; + + dev_add_pack(&x25_packet_type); + + rc = register_netdevice_notifier(&x25_dev_notifier); + if (rc) + goto out_sock; + + rc = x25_register_sysctl(); + if (rc) + goto out_dev; + + rc = x25_proc_init(); + if (rc) + goto out_sysctl; + + pr_info("Linux Version 0.2\n"); + +out: + return rc; +out_sysctl: + x25_unregister_sysctl(); +out_dev: + unregister_netdevice_notifier(&x25_dev_notifier); +out_sock: + dev_remove_pack(&x25_packet_type); + sock_unregister(AF_X25); +out_proto: + proto_unregister(&x25_proto); + goto out; +} +module_init(x25_init); + +static void __exit x25_exit(void) +{ + x25_proc_exit(); + x25_link_free(); + x25_route_free(); + + x25_unregister_sysctl(); + + unregister_netdevice_notifier(&x25_dev_notifier); + + dev_remove_pack(&x25_packet_type); + + sock_unregister(AF_X25); + proto_unregister(&x25_proto); +} +module_exit(x25_exit); + +MODULE_AUTHOR("Jonathan Naylor <g4klx@g4klx.demon.co.uk>"); +MODULE_DESCRIPTION("The X.25 Packet Layer network layer protocol"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NETPROTO(PF_X25); diff --git a/net/x25/sysctl_net_x25.c b/net/x25/sysctl_net_x25.c new file mode 100644 index 000000000..e9802afa4 --- /dev/null +++ b/net/x25/sysctl_net_x25.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0 +/* -*- linux-c -*- + * sysctl_net_x25.c: sysctl interface to net X.25 subsystem. + * + * Begun April 1, 1996, Mike Shaver. + * Added /proc/sys/net/x25 directory entry (empty =) ). [MS] + */ + +#include <linux/sysctl.h> +#include <linux/skbuff.h> +#include <linux/socket.h> +#include <linux/netdevice.h> +#include <linux/init.h> +#include <net/x25.h> + +static int min_timer[] = { 1 * HZ }; +static int max_timer[] = { 300 * HZ }; + +static struct ctl_table_header *x25_table_header; + +static struct ctl_table x25_table[] = { + { + .procname = "restart_request_timeout", + .data = &sysctl_x25_restart_request_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_timer, + .extra2 = &max_timer, + }, + { + .procname = "call_request_timeout", + .data = &sysctl_x25_call_request_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_timer, + .extra2 = &max_timer, + }, + { + .procname = "reset_request_timeout", + .data = &sysctl_x25_reset_request_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_timer, + .extra2 = &max_timer, + }, + { + .procname = "clear_request_timeout", + .data = &sysctl_x25_clear_request_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_timer, + .extra2 = &max_timer, + }, + { + .procname = "acknowledgement_hold_back_timeout", + .data = &sysctl_x25_ack_holdback_timeout, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &min_timer, + .extra2 = &max_timer, + }, + { + .procname = "x25_forward", + .data = &sysctl_x25_forward, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { }, +}; + +int __init x25_register_sysctl(void) +{ + x25_table_header = register_net_sysctl(&init_net, "net/x25", x25_table); + if (!x25_table_header) + return -ENOMEM; + return 0; +} + +void x25_unregister_sysctl(void) +{ + unregister_net_sysctl_table(x25_table_header); +} diff --git a/net/x25/x25_dev.c b/net/x25/x25_dev.c new file mode 100644 index 000000000..748d8630a --- /dev/null +++ b/net/x25/x25_dev.c @@ -0,0 +1,216 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, randomly fail to work with new + * releases, misbehave and/or generally screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * 2000-09-04 Henner Eisen Prevent freeing a dangling skb. + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/kernel.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <linux/slab.h> +#include <net/sock.h> +#include <linux/if_arp.h> +#include <net/x25.h> +#include <net/x25device.h> + +static int x25_receive_data(struct sk_buff *skb, struct x25_neigh *nb) +{ + struct sock *sk; + unsigned short frametype; + unsigned int lci; + + if (!pskb_may_pull(skb, X25_STD_MIN_LEN)) + return 0; + + frametype = skb->data[2]; + lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF); + + /* + * LCI of zero is always for us, and its always a link control + * frame. + */ + if (lci == 0) { + x25_link_control(skb, nb, frametype); + return 0; + } + + /* + * Find an existing socket. + */ + if ((sk = x25_find_socket(lci, nb)) != NULL) { + int queued = 1; + + skb_reset_transport_header(skb); + bh_lock_sock(sk); + if (!sock_owned_by_user(sk)) { + queued = x25_process_rx_frame(sk, skb); + } else { + queued = !sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)); + } + bh_unlock_sock(sk); + sock_put(sk); + return queued; + } + + /* + * Is is a Call Request ? if so process it. + */ + if (frametype == X25_CALL_REQUEST) + return x25_rx_call_request(skb, nb, lci); + + /* + * Its not a Call Request, nor is it a control frame. + * Can we forward it? + */ + + if (x25_forward_data(lci, nb, skb)) { + if (frametype == X25_CLEAR_CONFIRMATION) { + x25_clear_forward_by_lci(lci); + } + kfree_skb(skb); + return 1; + } + +/* + x25_transmit_clear_request(nb, lci, 0x0D); +*/ + + if (frametype != X25_CLEAR_CONFIRMATION) + pr_debug("x25_receive_data(): unknown frame type %2x\n",frametype); + + return 0; +} + +int x25_lapb_receive_frame(struct sk_buff *skb, struct net_device *dev, + struct packet_type *ptype, struct net_device *orig_dev) +{ + struct sk_buff *nskb; + struct x25_neigh *nb; + + if (!net_eq(dev_net(dev), &init_net)) + goto drop; + + nskb = skb_copy(skb, GFP_ATOMIC); + if (!nskb) + goto drop; + kfree_skb(skb); + skb = nskb; + + /* + * Packet received from unrecognised device, throw it away. + */ + nb = x25_get_neigh(dev); + if (!nb) { + pr_debug("unknown neighbour - %s\n", dev->name); + goto drop; + } + + if (!pskb_may_pull(skb, 1)) { + x25_neigh_put(nb); + goto drop; + } + + switch (skb->data[0]) { + + case X25_IFACE_DATA: + skb_pull(skb, 1); + if (x25_receive_data(skb, nb)) { + x25_neigh_put(nb); + goto out; + } + break; + + case X25_IFACE_CONNECT: + x25_link_established(nb); + break; + + case X25_IFACE_DISCONNECT: + x25_link_terminated(nb); + break; + } + x25_neigh_put(nb); +drop: + kfree_skb(skb); +out: + return 0; +} + +void x25_establish_link(struct x25_neigh *nb) +{ + struct sk_buff *skb; + unsigned char *ptr; + + switch (nb->dev->type) { + case ARPHRD_X25: + if ((skb = alloc_skb(1, GFP_ATOMIC)) == NULL) { + pr_err("x25_dev: out of memory\n"); + return; + } + ptr = skb_put(skb, 1); + *ptr = X25_IFACE_CONNECT; + break; + + default: + return; + } + + skb->protocol = htons(ETH_P_X25); + skb->dev = nb->dev; + + dev_queue_xmit(skb); +} + +void x25_terminate_link(struct x25_neigh *nb) +{ + struct sk_buff *skb; + unsigned char *ptr; + + if (nb->dev->type != ARPHRD_X25) + return; + + skb = alloc_skb(1, GFP_ATOMIC); + if (!skb) { + pr_err("x25_dev: out of memory\n"); + return; + } + + ptr = skb_put(skb, 1); + *ptr = X25_IFACE_DISCONNECT; + + skb->protocol = htons(ETH_P_X25); + skb->dev = nb->dev; + dev_queue_xmit(skb); +} + +void x25_send_frame(struct sk_buff *skb, struct x25_neigh *nb) +{ + unsigned char *dptr; + + skb_reset_network_header(skb); + + switch (nb->dev->type) { + case ARPHRD_X25: + dptr = skb_push(skb, 1); + *dptr = X25_IFACE_DATA; + break; + + default: + kfree_skb(skb); + return; + } + + skb->protocol = htons(ETH_P_X25); + skb->dev = nb->dev; + + dev_queue_xmit(skb); +} diff --git a/net/x25/x25_facilities.c b/net/x25/x25_facilities.c new file mode 100644 index 000000000..8e1a49b0c --- /dev/null +++ b/net/x25/x25_facilities.c @@ -0,0 +1,350 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Split from x25_subr.c + * mar/20/00 Daniela Squassoni Disabling/enabling of facilities + * negotiation. + * apr/14/05 Shaun Pereira - Allow fast select with no restriction + * on response. + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/x25.h> + +/** + * x25_parse_facilities - Parse facilities from skb into the facilities structs + * + * @skb: sk_buff to parse + * @facilities: Regular facilities, updated as facilities are found + * @dte_facs: ITU DTE facilities, updated as DTE facilities are found + * @vc_fac_mask: mask is updated with all facilities found + * + * Return codes: + * -1 - Parsing error, caller should drop call and clean up + * 0 - Parse OK, this skb has no facilities + * >0 - Parse OK, returns the length of the facilities header + * + */ +int x25_parse_facilities(struct sk_buff *skb, struct x25_facilities *facilities, + struct x25_dte_facilities *dte_facs, unsigned long *vc_fac_mask) +{ + unsigned char *p; + unsigned int len; + + *vc_fac_mask = 0; + + /* + * The kernel knows which facilities were set on an incoming call but + * currently this information is not available to userspace. Here we + * give userspace who read incoming call facilities 0 length to indicate + * it wasn't set. + */ + dte_facs->calling_len = 0; + dte_facs->called_len = 0; + memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae)); + memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae)); + + if (!pskb_may_pull(skb, 1)) + return 0; + + len = skb->data[0]; + + if (!pskb_may_pull(skb, 1 + len)) + return -1; + + p = skb->data + 1; + + while (len > 0) { + switch (*p & X25_FAC_CLASS_MASK) { + case X25_FAC_CLASS_A: + if (len < 2) + return -1; + switch (*p) { + case X25_FAC_REVERSE: + if((p[1] & 0x81) == 0x81) { + facilities->reverse = p[1] & 0x81; + *vc_fac_mask |= X25_MASK_REVERSE; + break; + } + + if((p[1] & 0x01) == 0x01) { + facilities->reverse = p[1] & 0x01; + *vc_fac_mask |= X25_MASK_REVERSE; + break; + } + + if((p[1] & 0x80) == 0x80) { + facilities->reverse = p[1] & 0x80; + *vc_fac_mask |= X25_MASK_REVERSE; + break; + } + + if(p[1] == 0x00) { + facilities->reverse + = X25_DEFAULT_REVERSE; + *vc_fac_mask |= X25_MASK_REVERSE; + break; + } + fallthrough; + case X25_FAC_THROUGHPUT: + facilities->throughput = p[1]; + *vc_fac_mask |= X25_MASK_THROUGHPUT; + break; + case X25_MARKER: + break; + default: + pr_debug("unknown facility " + "%02X, value %02X\n", + p[0], p[1]); + break; + } + p += 2; + len -= 2; + break; + case X25_FAC_CLASS_B: + if (len < 3) + return -1; + switch (*p) { + case X25_FAC_PACKET_SIZE: + facilities->pacsize_in = p[1]; + facilities->pacsize_out = p[2]; + *vc_fac_mask |= X25_MASK_PACKET_SIZE; + break; + case X25_FAC_WINDOW_SIZE: + facilities->winsize_in = p[1]; + facilities->winsize_out = p[2]; + *vc_fac_mask |= X25_MASK_WINDOW_SIZE; + break; + default: + pr_debug("unknown facility " + "%02X, values %02X, %02X\n", + p[0], p[1], p[2]); + break; + } + p += 3; + len -= 3; + break; + case X25_FAC_CLASS_C: + if (len < 4) + return -1; + pr_debug("unknown facility %02X, " + "values %02X, %02X, %02X\n", + p[0], p[1], p[2], p[3]); + p += 4; + len -= 4; + break; + case X25_FAC_CLASS_D: + if (len < p[1] + 2) + return -1; + switch (*p) { + case X25_FAC_CALLING_AE: + if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1) + return -1; + if (p[2] > X25_MAX_AE_LEN) + return -1; + dte_facs->calling_len = p[2]; + memcpy(dte_facs->calling_ae, &p[3], p[1] - 1); + *vc_fac_mask |= X25_MASK_CALLING_AE; + break; + case X25_FAC_CALLED_AE: + if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1) + return -1; + if (p[2] > X25_MAX_AE_LEN) + return -1; + dte_facs->called_len = p[2]; + memcpy(dte_facs->called_ae, &p[3], p[1] - 1); + *vc_fac_mask |= X25_MASK_CALLED_AE; + break; + default: + pr_debug("unknown facility %02X," + "length %d\n", p[0], p[1]); + break; + } + len -= p[1] + 2; + p += p[1] + 2; + break; + } + } + + return p - skb->data; +} + +/* + * Create a set of facilities. + */ +int x25_create_facilities(unsigned char *buffer, + struct x25_facilities *facilities, + struct x25_dte_facilities *dte_facs, unsigned long facil_mask) +{ + unsigned char *p = buffer + 1; + int len; + + if (!facil_mask) { + /* + * Length of the facilities field in call_req or + * call_accept packets + */ + buffer[0] = 0; + len = 1; /* 1 byte for the length field */ + return len; + } + + if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) { + *p++ = X25_FAC_REVERSE; + *p++ = facilities->reverse; + } + + if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) { + *p++ = X25_FAC_THROUGHPUT; + *p++ = facilities->throughput; + } + + if ((facilities->pacsize_in || facilities->pacsize_out) && + (facil_mask & X25_MASK_PACKET_SIZE)) { + *p++ = X25_FAC_PACKET_SIZE; + *p++ = facilities->pacsize_in ? : facilities->pacsize_out; + *p++ = facilities->pacsize_out ? : facilities->pacsize_in; + } + + if ((facilities->winsize_in || facilities->winsize_out) && + (facil_mask & X25_MASK_WINDOW_SIZE)) { + *p++ = X25_FAC_WINDOW_SIZE; + *p++ = facilities->winsize_in ? : facilities->winsize_out; + *p++ = facilities->winsize_out ? : facilities->winsize_in; + } + + if (facil_mask & (X25_MASK_CALLING_AE|X25_MASK_CALLED_AE)) { + *p++ = X25_MARKER; + *p++ = X25_DTE_SERVICES; + } + + if (dte_facs->calling_len && (facil_mask & X25_MASK_CALLING_AE)) { + unsigned int bytecount = (dte_facs->calling_len + 1) >> 1; + *p++ = X25_FAC_CALLING_AE; + *p++ = 1 + bytecount; + *p++ = dte_facs->calling_len; + memcpy(p, dte_facs->calling_ae, bytecount); + p += bytecount; + } + + if (dte_facs->called_len && (facil_mask & X25_MASK_CALLED_AE)) { + unsigned int bytecount = (dte_facs->called_len % 2) ? + dte_facs->called_len / 2 + 1 : + dte_facs->called_len / 2; + *p++ = X25_FAC_CALLED_AE; + *p++ = 1 + bytecount; + *p++ = dte_facs->called_len; + memcpy(p, dte_facs->called_ae, bytecount); + p+=bytecount; + } + + len = p - buffer; + buffer[0] = len - 1; + + return len; +} + +/* + * Try to reach a compromise on a set of facilities. + * + * The only real problem is with reverse charging. + */ +int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk, + struct x25_facilities *new, struct x25_dte_facilities *dte) +{ + struct x25_sock *x25 = x25_sk(sk); + struct x25_facilities *ours = &x25->facilities; + struct x25_facilities theirs; + int len; + + memset(&theirs, 0, sizeof(theirs)); + memcpy(new, ours, sizeof(*new)); + memset(dte, 0, sizeof(*dte)); + + len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask); + if (len < 0) + return len; + + /* + * They want reverse charging, we won't accept it. + */ + if ((theirs.reverse & 0x01 ) && (ours->reverse & 0x01)) { + SOCK_DEBUG(sk, "X.25: rejecting reverse charging request\n"); + return -1; + } + + new->reverse = theirs.reverse; + + if (theirs.throughput) { + int theirs_in = theirs.throughput & 0x0f; + int theirs_out = theirs.throughput & 0xf0; + int ours_in = ours->throughput & 0x0f; + int ours_out = ours->throughput & 0xf0; + if (!ours_in || theirs_in < ours_in) { + SOCK_DEBUG(sk, "X.25: inbound throughput negotiated\n"); + new->throughput = (new->throughput & 0xf0) | theirs_in; + } + if (!ours_out || theirs_out < ours_out) { + SOCK_DEBUG(sk, + "X.25: outbound throughput negotiated\n"); + new->throughput = (new->throughput & 0x0f) | theirs_out; + } + } + + if (theirs.pacsize_in && theirs.pacsize_out) { + if (theirs.pacsize_in < ours->pacsize_in) { + SOCK_DEBUG(sk, "X.25: packet size inwards negotiated down\n"); + new->pacsize_in = theirs.pacsize_in; + } + if (theirs.pacsize_out < ours->pacsize_out) { + SOCK_DEBUG(sk, "X.25: packet size outwards negotiated down\n"); + new->pacsize_out = theirs.pacsize_out; + } + } + + if (theirs.winsize_in && theirs.winsize_out) { + if (theirs.winsize_in < ours->winsize_in) { + SOCK_DEBUG(sk, "X.25: window size inwards negotiated down\n"); + new->winsize_in = theirs.winsize_in; + } + if (theirs.winsize_out < ours->winsize_out) { + SOCK_DEBUG(sk, "X.25: window size outwards negotiated down\n"); + new->winsize_out = theirs.winsize_out; + } + } + + return len; +} + +/* + * Limit values of certain facilities according to the capability of the + * currently attached x25 link. + */ +void x25_limit_facilities(struct x25_facilities *facilities, + struct x25_neigh *nb) +{ + + if (!nb->extended) { + if (facilities->winsize_in > 7) { + pr_debug("incoming winsize limited to 7\n"); + facilities->winsize_in = 7; + } + if (facilities->winsize_out > 7) { + facilities->winsize_out = 7; + pr_debug("outgoing winsize limited to 7\n"); + } + } +} diff --git a/net/x25/x25_forward.c b/net/x25/x25_forward.c new file mode 100644 index 000000000..21b30b56e --- /dev/null +++ b/net/x25/x25_forward.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * History + * 03-01-2007 Added forwarding for x.25 Andrew Hendry + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/if_arp.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <net/x25.h> + +LIST_HEAD(x25_forward_list); +DEFINE_RWLOCK(x25_forward_list_lock); + +int x25_forward_call(struct x25_address *dest_addr, struct x25_neigh *from, + struct sk_buff *skb, int lci) +{ + struct x25_route *rt; + struct x25_neigh *neigh_new = NULL; + struct x25_forward *x25_frwd, *new_frwd; + struct sk_buff *skbn; + short same_lci = 0; + int rc = 0; + + if ((rt = x25_get_route(dest_addr)) == NULL) + goto out_no_route; + + if ((neigh_new = x25_get_neigh(rt->dev)) == NULL) { + /* This shouldn't happen, if it occurs somehow + * do something sensible + */ + goto out_put_route; + } + + /* Avoid a loop. This is the normal exit path for a + * system with only one x.25 iface and default route + */ + if (rt->dev == from->dev) { + goto out_put_nb; + } + + /* Remote end sending a call request on an already + * established LCI? It shouldn't happen, just in case.. + */ + read_lock_bh(&x25_forward_list_lock); + list_for_each_entry(x25_frwd, &x25_forward_list, node) { + if (x25_frwd->lci == lci) { + pr_warn("call request for lci which is already registered!, transmitting but not registering new pair\n"); + same_lci = 1; + } + } + read_unlock_bh(&x25_forward_list_lock); + + /* Save the forwarding details for future traffic */ + if (!same_lci){ + if ((new_frwd = kmalloc(sizeof(struct x25_forward), + GFP_ATOMIC)) == NULL){ + rc = -ENOMEM; + goto out_put_nb; + } + new_frwd->lci = lci; + new_frwd->dev1 = rt->dev; + new_frwd->dev2 = from->dev; + write_lock_bh(&x25_forward_list_lock); + list_add(&new_frwd->node, &x25_forward_list); + write_unlock_bh(&x25_forward_list_lock); + } + + /* Forward the call request */ + if ( (skbn = skb_clone(skb, GFP_ATOMIC)) == NULL){ + goto out_put_nb; + } + x25_transmit_link(skbn, neigh_new); + rc = 1; + + +out_put_nb: + x25_neigh_put(neigh_new); + +out_put_route: + x25_route_put(rt); + +out_no_route: + return rc; +} + + +int x25_forward_data(int lci, struct x25_neigh *from, struct sk_buff *skb) { + + struct x25_forward *frwd; + struct net_device *peer = NULL; + struct x25_neigh *nb; + struct sk_buff *skbn; + int rc = 0; + + read_lock_bh(&x25_forward_list_lock); + list_for_each_entry(frwd, &x25_forward_list, node) { + if (frwd->lci == lci) { + /* The call is established, either side can send */ + if (from->dev == frwd->dev1) { + peer = frwd->dev2; + } else { + peer = frwd->dev1; + } + break; + } + } + read_unlock_bh(&x25_forward_list_lock); + + if ( (nb = x25_get_neigh(peer)) == NULL) + goto out; + + if ( (skbn = pskb_copy(skb, GFP_ATOMIC)) == NULL){ + goto output; + + } + x25_transmit_link(skbn, nb); + + rc = 1; +output: + x25_neigh_put(nb); +out: + return rc; +} + +void x25_clear_forward_by_lci(unsigned int lci) +{ + struct x25_forward *fwd, *tmp; + + write_lock_bh(&x25_forward_list_lock); + + list_for_each_entry_safe(fwd, tmp, &x25_forward_list, node) { + if (fwd->lci == lci) { + list_del(&fwd->node); + kfree(fwd); + } + } + write_unlock_bh(&x25_forward_list_lock); +} + + +void x25_clear_forward_by_dev(struct net_device *dev) +{ + struct x25_forward *fwd, *tmp; + + write_lock_bh(&x25_forward_list_lock); + + list_for_each_entry_safe(fwd, tmp, &x25_forward_list, node) { + if ((fwd->dev1 == dev) || (fwd->dev2 == dev)){ + list_del(&fwd->node); + kfree(fwd); + } + } + write_unlock_bh(&x25_forward_list_lock); +} diff --git a/net/x25/x25_in.c b/net/x25/x25_in.c new file mode 100644 index 000000000..b981a4828 --- /dev/null +++ b/net/x25/x25_in.c @@ -0,0 +1,456 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor Centralised disconnection code. + * New timer architecture. + * 2000-03-20 Daniela Squassoni Disabling/enabling of facilities + * negotiation. + * 2000-11-10 Henner Eisen Check and reset for out-of-sequence + * i-frames. + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <net/x25.h> + +static int x25_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more) +{ + struct sk_buff *skbo, *skbn = skb; + struct x25_sock *x25 = x25_sk(sk); + + if (more) { + x25->fraglen += skb->len; + skb_queue_tail(&x25->fragment_queue, skb); + skb_set_owner_r(skb, sk); + return 0; + } + + if (x25->fraglen > 0) { /* End of fragment */ + int len = x25->fraglen + skb->len; + + if ((skbn = alloc_skb(len, GFP_ATOMIC)) == NULL){ + kfree_skb(skb); + return 1; + } + + skb_queue_tail(&x25->fragment_queue, skb); + + skb_reset_transport_header(skbn); + + skbo = skb_dequeue(&x25->fragment_queue); + skb_copy_from_linear_data(skbo, skb_put(skbn, skbo->len), + skbo->len); + kfree_skb(skbo); + + while ((skbo = + skb_dequeue(&x25->fragment_queue)) != NULL) { + skb_pull(skbo, (x25->neighbour->extended) ? + X25_EXT_MIN_LEN : X25_STD_MIN_LEN); + skb_copy_from_linear_data(skbo, + skb_put(skbn, skbo->len), + skbo->len); + kfree_skb(skbo); + } + + x25->fraglen = 0; + } + + skb_set_owner_r(skbn, sk); + skb_queue_tail(&sk->sk_receive_queue, skbn); + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk); + + return 0; +} + +/* + * State machine for state 1, Awaiting Call Accepted State. + * The handling of the timer(s) is in file x25_timer.c. + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct x25_address source_addr, dest_addr; + int len; + struct x25_sock *x25 = x25_sk(sk); + + switch (frametype) { + case X25_CALL_ACCEPTED: { + + x25_stop_timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->va = 0; + x25->vr = 0; + x25->vl = 0; + x25->state = X25_STATE_3; + sk->sk_state = TCP_ESTABLISHED; + /* + * Parse the data in the frame. + */ + if (!pskb_may_pull(skb, X25_STD_MIN_LEN)) + goto out_clear; + skb_pull(skb, X25_STD_MIN_LEN); + + len = x25_parse_address_block(skb, &source_addr, + &dest_addr); + if (len > 0) + skb_pull(skb, len); + else if (len < 0) + goto out_clear; + + len = x25_parse_facilities(skb, &x25->facilities, + &x25->dte_facilities, + &x25->vc_facil_mask); + if (len > 0) + skb_pull(skb, len); + else if (len < 0) + goto out_clear; + /* + * Copy any Call User Data. + */ + if (skb->len > 0) { + if (skb->len > X25_MAX_CUD_LEN) + goto out_clear; + + skb_copy_bits(skb, 0, x25->calluserdata.cuddata, + skb->len); + x25->calluserdata.cudlength = skb->len; + } + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + break; + } + case X25_CALL_REQUEST: + /* call collision */ + x25->causediag.cause = 0x01; + x25->causediag.diagnostic = 0x48; + + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25_disconnect(sk, EISCONN, 0x01, 0x48); + break; + + case X25_CLEAR_REQUEST: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) + goto out_clear; + + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, ECONNREFUSED, skb->data[3], skb->data[4]); + break; + + default: + break; + } + + return 0; + +out_clear: + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25->state = X25_STATE_2; + x25_start_t23timer(sk); + return 0; +} + +/* + * State machine for state 2, Awaiting Clear Confirmation State. + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state2_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + switch (frametype) { + + case X25_CLEAR_REQUEST: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) + goto out_clear; + + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + case X25_CLEAR_CONFIRMATION: + x25_disconnect(sk, 0, 0, 0); + break; + + default: + break; + } + + return 0; + +out_clear: + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25_start_t23timer(sk); + return 0; +} + +/* + * State machine for state 3, Connected State. + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m) +{ + int queued = 0; + int modulus; + struct x25_sock *x25 = x25_sk(sk); + + modulus = (x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS; + + switch (frametype) { + + case X25_RESET_REQUEST: + x25_write_internal(sk, X25_RESET_CONFIRMATION); + x25_stop_timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25_requeue_frames(sk); + break; + + case X25_CLEAR_REQUEST: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) + goto out_clear; + + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + case X25_RR: + case X25_RNR: + if (!x25_validate_nr(sk, nr)) { + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + } else { + x25_frames_acked(sk, nr); + if (frametype == X25_RNR) { + x25->condition |= X25_COND_PEER_RX_BUSY; + } else { + x25->condition &= ~X25_COND_PEER_RX_BUSY; + } + } + break; + + case X25_DATA: /* XXX */ + x25->condition &= ~X25_COND_PEER_RX_BUSY; + if ((ns != x25->vr) || !x25_validate_nr(sk, nr)) { + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + break; + } + x25_frames_acked(sk, nr); + if (ns == x25->vr) { + if (x25_queue_rx_frame(sk, skb, m) == 0) { + x25->vr = (x25->vr + 1) % modulus; + queued = 1; + } else { + /* Should never happen */ + x25_clear_queues(sk); + x25_write_internal(sk, X25_RESET_REQUEST); + x25_start_t22timer(sk); + x25->condition = 0x00; + x25->vs = 0; + x25->vr = 0; + x25->va = 0; + x25->vl = 0; + x25->state = X25_STATE_4; + break; + } + if (atomic_read(&sk->sk_rmem_alloc) > + (sk->sk_rcvbuf >> 1)) + x25->condition |= X25_COND_OWN_RX_BUSY; + } + /* + * If the window is full Ack it immediately, else + * start the holdback timer. + */ + if (((x25->vl + x25->facilities.winsize_in) % modulus) == x25->vr) { + x25->condition &= ~X25_COND_ACK_PENDING; + x25_stop_timer(sk); + x25_enquiry_response(sk); + } else { + x25->condition |= X25_COND_ACK_PENDING; + x25_start_t2timer(sk); + } + break; + + case X25_INTERRUPT_CONFIRMATION: + clear_bit(X25_INTERRUPT_FLAG, &x25->flags); + break; + + case X25_INTERRUPT: + if (sock_flag(sk, SOCK_URGINLINE)) + queued = !sock_queue_rcv_skb(sk, skb); + else { + skb_set_owner_r(skb, sk); + skb_queue_tail(&x25->interrupt_in_queue, skb); + queued = 1; + } + sk_send_sigurg(sk); + x25_write_internal(sk, X25_INTERRUPT_CONFIRMATION); + break; + + default: + pr_warn("unknown %02X in state 3\n", frametype); + break; + } + + return queued; + +out_clear: + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25->state = X25_STATE_2; + x25_start_t23timer(sk); + return 0; +} + +/* + * State machine for state 4, Awaiting Reset Confirmation State. + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state4_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct x25_sock *x25 = x25_sk(sk); + + switch (frametype) { + + case X25_RESET_REQUEST: + x25_write_internal(sk, X25_RESET_CONFIRMATION); + fallthrough; + case X25_RESET_CONFIRMATION: { + x25_stop_timer(sk); + x25->condition = 0x00; + x25->va = 0; + x25->vr = 0; + x25->vs = 0; + x25->vl = 0; + x25->state = X25_STATE_3; + x25_requeue_frames(sk); + break; + } + case X25_CLEAR_REQUEST: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) + goto out_clear; + + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + default: + break; + } + + return 0; + +out_clear: + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25->state = X25_STATE_2; + x25_start_t23timer(sk); + return 0; +} + +/* + * State machine for state 5, Call Accepted / Call Connected pending (X25_ACCPT_APPRV_FLAG). + * The handling of the timer(s) is in file x25_timer.c + * Handling of state 0 and connection release is in af_x25.c. + */ +static int x25_state5_machine(struct sock *sk, struct sk_buff *skb, int frametype) +{ + struct x25_sock *x25 = x25_sk(sk); + + switch (frametype) { + case X25_CLEAR_REQUEST: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 2)) { + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25->state = X25_STATE_2; + x25_start_t23timer(sk); + return 0; + } + + x25_write_internal(sk, X25_CLEAR_CONFIRMATION); + x25_disconnect(sk, 0, skb->data[3], skb->data[4]); + break; + + default: + break; + } + + return 0; +} + +/* Higher level upcall for a LAPB frame */ +int x25_process_rx_frame(struct sock *sk, struct sk_buff *skb) +{ + struct x25_sock *x25 = x25_sk(sk); + int queued = 0, frametype, ns, nr, q, d, m; + + if (x25->state == X25_STATE_0) + return 0; + + frametype = x25_decode(sk, skb, &ns, &nr, &q, &d, &m); + + switch (x25->state) { + case X25_STATE_1: + queued = x25_state1_machine(sk, skb, frametype); + break; + case X25_STATE_2: + queued = x25_state2_machine(sk, skb, frametype); + break; + case X25_STATE_3: + queued = x25_state3_machine(sk, skb, frametype, ns, nr, q, d, m); + break; + case X25_STATE_4: + queued = x25_state4_machine(sk, skb, frametype); + break; + case X25_STATE_5: + queued = x25_state5_machine(sk, skb, frametype); + break; + } + + x25_kick(sk); + + return queued; +} + +int x25_backlog_rcv(struct sock *sk, struct sk_buff *skb) +{ + int queued = x25_process_rx_frame(sk, skb); + + if (!queued) + kfree_skb(skb); + + return 0; +} diff --git a/net/x25/x25_link.c b/net/x25/x25_link.c new file mode 100644 index 000000000..5460b9146 --- /dev/null +++ b/net/x25/x25_link.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor New timer architecture. + * mar/20/00 Daniela Squassoni Disabling/enabling of facilities + * negotiation. + * 2000-09-04 Henner Eisen dev_hold() / dev_put() for x25_neigh. + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/kernel.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <linux/slab.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <linux/uaccess.h> +#include <linux/init.h> +#include <net/x25.h> + +LIST_HEAD(x25_neigh_list); +DEFINE_RWLOCK(x25_neigh_list_lock); + +static void x25_t20timer_expiry(struct timer_list *); + +static void x25_transmit_restart_confirmation(struct x25_neigh *nb); +static void x25_transmit_restart_request(struct x25_neigh *nb); + +/* + * Linux set/reset timer routines + */ +static inline void x25_start_t20timer(struct x25_neigh *nb) +{ + mod_timer(&nb->t20timer, jiffies + nb->t20); +} + +static void x25_t20timer_expiry(struct timer_list *t) +{ + struct x25_neigh *nb = from_timer(nb, t, t20timer); + + x25_transmit_restart_request(nb); + + x25_start_t20timer(nb); +} + +static inline void x25_stop_t20timer(struct x25_neigh *nb) +{ + del_timer(&nb->t20timer); +} + +/* + * This handles all restart and diagnostic frames. + */ +void x25_link_control(struct sk_buff *skb, struct x25_neigh *nb, + unsigned short frametype) +{ + struct sk_buff *skbn; + + switch (frametype) { + case X25_RESTART_REQUEST: + switch (nb->state) { + case X25_LINK_STATE_0: + /* This can happen when the x25 module just gets loaded + * and doesn't know layer 2 has already connected + */ + nb->state = X25_LINK_STATE_3; + x25_transmit_restart_confirmation(nb); + break; + case X25_LINK_STATE_2: + x25_stop_t20timer(nb); + nb->state = X25_LINK_STATE_3; + break; + case X25_LINK_STATE_3: + /* clear existing virtual calls */ + x25_kill_by_neigh(nb); + + x25_transmit_restart_confirmation(nb); + break; + } + break; + + case X25_RESTART_CONFIRMATION: + switch (nb->state) { + case X25_LINK_STATE_2: + x25_stop_t20timer(nb); + nb->state = X25_LINK_STATE_3; + break; + case X25_LINK_STATE_3: + /* clear existing virtual calls */ + x25_kill_by_neigh(nb); + + x25_transmit_restart_request(nb); + nb->state = X25_LINK_STATE_2; + x25_start_t20timer(nb); + break; + } + break; + + case X25_DIAGNOSTIC: + if (!pskb_may_pull(skb, X25_STD_MIN_LEN + 4)) + break; + + pr_warn("diagnostic #%d - %02X %02X %02X\n", + skb->data[3], skb->data[4], + skb->data[5], skb->data[6]); + break; + + default: + pr_warn("received unknown %02X with LCI 000\n", + frametype); + break; + } + + if (nb->state == X25_LINK_STATE_3) + while ((skbn = skb_dequeue(&nb->queue)) != NULL) + x25_send_frame(skbn, nb); +} + +/* + * This routine is called when a Restart Request is needed + */ +static void x25_transmit_restart_request(struct x25_neigh *nb) +{ + unsigned char *dptr; + int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; + struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); + + if (!skb) + return; + + skb_reserve(skb, X25_MAX_L2_LEN); + + dptr = skb_put(skb, X25_STD_MIN_LEN + 2); + + *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; + *dptr++ = 0x00; + *dptr++ = X25_RESTART_REQUEST; + *dptr++ = 0x00; + *dptr++ = 0; + + skb->sk = NULL; + + x25_send_frame(skb, nb); +} + +/* + * This routine is called when a Restart Confirmation is needed + */ +static void x25_transmit_restart_confirmation(struct x25_neigh *nb) +{ + unsigned char *dptr; + int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN; + struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); + + if (!skb) + return; + + skb_reserve(skb, X25_MAX_L2_LEN); + + dptr = skb_put(skb, X25_STD_MIN_LEN); + + *dptr++ = nb->extended ? X25_GFI_EXTSEQ : X25_GFI_STDSEQ; + *dptr++ = 0x00; + *dptr++ = X25_RESTART_CONFIRMATION; + + skb->sk = NULL; + + x25_send_frame(skb, nb); +} + +/* + * This routine is called when a Clear Request is needed outside of the context + * of a connected socket. + */ +void x25_transmit_clear_request(struct x25_neigh *nb, unsigned int lci, + unsigned char cause) +{ + unsigned char *dptr; + int len = X25_MAX_L2_LEN + X25_STD_MIN_LEN + 2; + struct sk_buff *skb = alloc_skb(len, GFP_ATOMIC); + + if (!skb) + return; + + skb_reserve(skb, X25_MAX_L2_LEN); + + dptr = skb_put(skb, X25_STD_MIN_LEN + 2); + + *dptr++ = ((lci >> 8) & 0x0F) | (nb->extended ? + X25_GFI_EXTSEQ : + X25_GFI_STDSEQ); + *dptr++ = (lci >> 0) & 0xFF; + *dptr++ = X25_CLEAR_REQUEST; + *dptr++ = cause; + *dptr++ = 0x00; + + skb->sk = NULL; + + x25_send_frame(skb, nb); +} + +void x25_transmit_link(struct sk_buff *skb, struct x25_neigh *nb) +{ + switch (nb->state) { + case X25_LINK_STATE_0: + skb_queue_tail(&nb->queue, skb); + nb->state = X25_LINK_STATE_1; + x25_establish_link(nb); + break; + case X25_LINK_STATE_1: + case X25_LINK_STATE_2: + skb_queue_tail(&nb->queue, skb); + break; + case X25_LINK_STATE_3: + x25_send_frame(skb, nb); + break; + } +} + +/* + * Called when the link layer has become established. + */ +void x25_link_established(struct x25_neigh *nb) +{ + switch (nb->state) { + case X25_LINK_STATE_0: + case X25_LINK_STATE_1: + x25_transmit_restart_request(nb); + nb->state = X25_LINK_STATE_2; + x25_start_t20timer(nb); + break; + } +} + +/* + * Called when the link layer has terminated, or an establishment + * request has failed. + */ + +void x25_link_terminated(struct x25_neigh *nb) +{ + nb->state = X25_LINK_STATE_0; + skb_queue_purge(&nb->queue); + x25_stop_t20timer(nb); + + /* Out of order: clear existing virtual calls (X.25 03/93 4.6.3) */ + x25_kill_by_neigh(nb); +} + +/* + * Add a new device. + */ +void x25_link_device_up(struct net_device *dev) +{ + struct x25_neigh *nb = kmalloc(sizeof(*nb), GFP_ATOMIC); + + if (!nb) + return; + + skb_queue_head_init(&nb->queue); + timer_setup(&nb->t20timer, x25_t20timer_expiry, 0); + + dev_hold(dev); + nb->dev = dev; + nb->state = X25_LINK_STATE_0; + nb->extended = 0; + /* + * Enables negotiation + */ + nb->global_facil_mask = X25_MASK_REVERSE | + X25_MASK_THROUGHPUT | + X25_MASK_PACKET_SIZE | + X25_MASK_WINDOW_SIZE; + nb->t20 = sysctl_x25_restart_request_timeout; + refcount_set(&nb->refcnt, 1); + + write_lock_bh(&x25_neigh_list_lock); + list_add(&nb->node, &x25_neigh_list); + write_unlock_bh(&x25_neigh_list_lock); +} + +/** + * __x25_remove_neigh - remove neighbour from x25_neigh_list + * @nb: - neigh to remove + * + * Remove neighbour from x25_neigh_list. If it was there. + * Caller must hold x25_neigh_list_lock. + */ +static void __x25_remove_neigh(struct x25_neigh *nb) +{ + if (nb->node.next) { + list_del(&nb->node); + x25_neigh_put(nb); + } +} + +/* + * A device has been removed, remove its links. + */ +void x25_link_device_down(struct net_device *dev) +{ + struct x25_neigh *nb; + struct list_head *entry, *tmp; + + write_lock_bh(&x25_neigh_list_lock); + + list_for_each_safe(entry, tmp, &x25_neigh_list) { + nb = list_entry(entry, struct x25_neigh, node); + + if (nb->dev == dev) { + __x25_remove_neigh(nb); + dev_put(dev); + } + } + + write_unlock_bh(&x25_neigh_list_lock); +} + +/* + * Given a device, return the neighbour address. + */ +struct x25_neigh *x25_get_neigh(struct net_device *dev) +{ + struct x25_neigh *nb, *use = NULL; + + read_lock_bh(&x25_neigh_list_lock); + list_for_each_entry(nb, &x25_neigh_list, node) { + if (nb->dev == dev) { + use = nb; + break; + } + } + + if (use) + x25_neigh_hold(use); + read_unlock_bh(&x25_neigh_list_lock); + return use; +} + +/* + * Handle the ioctls that control the subscription functions. + */ +int x25_subscr_ioctl(unsigned int cmd, void __user *arg) +{ + struct x25_subscrip_struct x25_subscr; + struct x25_neigh *nb; + struct net_device *dev; + int rc = -EINVAL; + + if (cmd != SIOCX25GSUBSCRIP && cmd != SIOCX25SSUBSCRIP) + goto out; + + rc = -EFAULT; + if (copy_from_user(&x25_subscr, arg, sizeof(x25_subscr))) + goto out; + + rc = -EINVAL; + if ((dev = x25_dev_get(x25_subscr.device)) == NULL) + goto out; + + if ((nb = x25_get_neigh(dev)) == NULL) + goto out_dev_put; + + dev_put(dev); + + if (cmd == SIOCX25GSUBSCRIP) { + read_lock_bh(&x25_neigh_list_lock); + x25_subscr.extended = nb->extended; + x25_subscr.global_facil_mask = nb->global_facil_mask; + read_unlock_bh(&x25_neigh_list_lock); + rc = copy_to_user(arg, &x25_subscr, + sizeof(x25_subscr)) ? -EFAULT : 0; + } else { + rc = -EINVAL; + if (!(x25_subscr.extended && x25_subscr.extended != 1)) { + rc = 0; + write_lock_bh(&x25_neigh_list_lock); + nb->extended = x25_subscr.extended; + nb->global_facil_mask = x25_subscr.global_facil_mask; + write_unlock_bh(&x25_neigh_list_lock); + } + } + x25_neigh_put(nb); +out: + return rc; +out_dev_put: + dev_put(dev); + goto out; +} + + +/* + * Release all memory associated with X.25 neighbour structures. + */ +void __exit x25_link_free(void) +{ + struct x25_neigh *nb; + struct list_head *entry, *tmp; + + write_lock_bh(&x25_neigh_list_lock); + + list_for_each_safe(entry, tmp, &x25_neigh_list) { + struct net_device *dev; + + nb = list_entry(entry, struct x25_neigh, node); + dev = nb->dev; + __x25_remove_neigh(nb); + dev_put(dev); + } + write_unlock_bh(&x25_neigh_list_lock); +} diff --git a/net/x25/x25_out.c b/net/x25/x25_out.c new file mode 100644 index 000000000..dbc0940bf --- /dev/null +++ b/net/x25/x25_out.c @@ -0,0 +1,226 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor New timer architecture. + * 2000-09-04 Henner Eisen Prevented x25_output() skb leakage. + * 2000-10-27 Henner Eisen MSG_DONTWAIT for fragment allocation. + * 2000-11-10 Henner Eisen x25_send_iframe(): re-queued frames + * needed cleaned seq-number fields. + */ + +#include <linux/slab.h> +#include <linux/socket.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/x25.h> + +static int x25_pacsize_to_bytes(unsigned int pacsize) +{ + int bytes = 1; + + if (!pacsize) + return 128; + + while (pacsize-- > 0) + bytes *= 2; + + return bytes; +} + +/* + * This is where all X.25 information frames pass. + * + * Returns the amount of user data bytes sent on success + * or a negative error code on failure. + */ +int x25_output(struct sock *sk, struct sk_buff *skb) +{ + struct sk_buff *skbn; + unsigned char header[X25_EXT_MIN_LEN]; + int err, frontlen, len; + int sent=0, noblock = X25_SKB_CB(skb)->flags & MSG_DONTWAIT; + struct x25_sock *x25 = x25_sk(sk); + int header_len = x25->neighbour->extended ? X25_EXT_MIN_LEN : + X25_STD_MIN_LEN; + int max_len = x25_pacsize_to_bytes(x25->facilities.pacsize_out); + + if (skb->len - header_len > max_len) { + /* Save a copy of the Header */ + skb_copy_from_linear_data(skb, header, header_len); + skb_pull(skb, header_len); + + frontlen = skb_headroom(skb); + + while (skb->len > 0) { + release_sock(sk); + skbn = sock_alloc_send_skb(sk, frontlen + max_len, + noblock, &err); + lock_sock(sk); + if (!skbn) { + if (err == -EWOULDBLOCK && noblock){ + kfree_skb(skb); + return sent; + } + SOCK_DEBUG(sk, "x25_output: fragment alloc" + " failed, err=%d, %d bytes " + "sent\n", err, sent); + return err; + } + + skb_reserve(skbn, frontlen); + + len = max_len > skb->len ? skb->len : max_len; + + /* Copy the user data */ + skb_copy_from_linear_data(skb, skb_put(skbn, len), len); + skb_pull(skb, len); + + /* Duplicate the Header */ + skb_push(skbn, header_len); + skb_copy_to_linear_data(skbn, header, header_len); + + if (skb->len > 0) { + if (x25->neighbour->extended) + skbn->data[3] |= X25_EXT_M_BIT; + else + skbn->data[2] |= X25_STD_M_BIT; + } + + skb_queue_tail(&sk->sk_write_queue, skbn); + sent += len; + } + + kfree_skb(skb); + } else { + skb_queue_tail(&sk->sk_write_queue, skb); + sent = skb->len - header_len; + } + return sent; +} + +/* + * 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 x25_send_iframe(struct sock *sk, struct sk_buff *skb) +{ + struct x25_sock *x25 = x25_sk(sk); + + if (!skb) + return; + + if (x25->neighbour->extended) { + skb->data[2] = (x25->vs << 1) & 0xFE; + skb->data[3] &= X25_EXT_M_BIT; + skb->data[3] |= (x25->vr << 1) & 0xFE; + } else { + skb->data[2] &= X25_STD_M_BIT; + skb->data[2] |= (x25->vs << 1) & 0x0E; + skb->data[2] |= (x25->vr << 5) & 0xE0; + } + + x25_transmit_link(skb, x25->neighbour); +} + +void x25_kick(struct sock *sk) +{ + struct sk_buff *skb, *skbn; + unsigned short start, end; + int modulus; + struct x25_sock *x25 = x25_sk(sk); + + if (x25->state != X25_STATE_3) + return; + + /* + * Transmit interrupt data. + */ + if (skb_peek(&x25->interrupt_out_queue) != NULL && + !test_and_set_bit(X25_INTERRUPT_FLAG, &x25->flags)) { + + skb = skb_dequeue(&x25->interrupt_out_queue); + x25_transmit_link(skb, x25->neighbour); + } + + if (x25->condition & X25_COND_PEER_RX_BUSY) + return; + + if (!skb_peek(&sk->sk_write_queue)) + return; + + modulus = x25->neighbour->extended ? X25_EMODULUS : X25_SMODULUS; + + start = skb_peek(&x25->ack_queue) ? x25->vs : x25->va; + end = (x25->va + x25->facilities.winsize_out) % modulus; + + if (start == end) + return; + + x25->vs = start; + + /* + * Transmit data until either we're out of data to send or + * the window is full. + */ + + 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. + */ + x25_send_iframe(sk, skbn); + + x25->vs = (x25->vs + 1) % modulus; + + /* + * Requeue the original data frame. + */ + skb_queue_tail(&x25->ack_queue, skb); + + } while (x25->vs != end && + (skb = skb_dequeue(&sk->sk_write_queue)) != NULL); + + x25->vl = x25->vr; + x25->condition &= ~X25_COND_ACK_PENDING; + + x25_stop_timer(sk); +} + +/* + * The following routines are taken from page 170 of the 7th ARRL Computer + * Networking Conference paper, as is the whole state machine. + */ + +void x25_enquiry_response(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + if (x25->condition & X25_COND_OWN_RX_BUSY) + x25_write_internal(sk, X25_RNR); + else + x25_write_internal(sk, X25_RR); + + x25->vl = x25->vr; + x25->condition &= ~X25_COND_ACK_PENDING; + + x25_stop_timer(sk); +} diff --git a/net/x25/x25_proc.c b/net/x25/x25_proc.c new file mode 100644 index 000000000..0412814a2 --- /dev/null +++ b/net/x25/x25_proc.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.4 with seq_file support + * + * History + * 2002/10/06 Arnaldo Carvalho de Melo seq_file support + */ + +#include <linux/init.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/export.h> +#include <net/net_namespace.h> +#include <net/sock.h> +#include <net/x25.h> + +#ifdef CONFIG_PROC_FS + +static void *x25_seq_route_start(struct seq_file *seq, loff_t *pos) + __acquires(x25_route_list_lock) +{ + read_lock_bh(&x25_route_list_lock); + return seq_list_start_head(&x25_route_list, *pos); +} + +static void *x25_seq_route_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_list_next(v, &x25_route_list, pos); +} + +static void x25_seq_route_stop(struct seq_file *seq, void *v) + __releases(x25_route_list_lock) +{ + read_unlock_bh(&x25_route_list_lock); +} + +static int x25_seq_route_show(struct seq_file *seq, void *v) +{ + struct x25_route *rt = list_entry(v, struct x25_route, node); + + if (v == &x25_route_list) { + seq_puts(seq, "Address Digits Device\n"); + goto out; + } + + rt = v; + seq_printf(seq, "%-15s %-6d %-5s\n", + rt->address.x25_addr, rt->sigdigits, + rt->dev ? rt->dev->name : "???"); +out: + return 0; +} + +static void *x25_seq_socket_start(struct seq_file *seq, loff_t *pos) + __acquires(x25_list_lock) +{ + read_lock_bh(&x25_list_lock); + return seq_hlist_start_head(&x25_list, *pos); +} + +static void *x25_seq_socket_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_hlist_next(v, &x25_list, pos); +} + +static void x25_seq_socket_stop(struct seq_file *seq, void *v) + __releases(x25_list_lock) +{ + read_unlock_bh(&x25_list_lock); +} + +static int x25_seq_socket_show(struct seq_file *seq, void *v) +{ + struct sock *s; + struct x25_sock *x25; + const char *devname; + + if (v == SEQ_START_TOKEN) { + seq_printf(seq, "dest_addr src_addr dev lci st vs vr " + "va t t2 t21 t22 t23 Snd-Q Rcv-Q inode\n"); + goto out; + } + + s = sk_entry(v); + x25 = x25_sk(s); + + if (!x25->neighbour || !x25->neighbour->dev) + devname = "???"; + else + devname = x25->neighbour->dev->name; + + seq_printf(seq, "%-10s %-10s %-5s %3.3X %d %d %d %d %3lu %3lu " + "%3lu %3lu %3lu %5d %5d %ld\n", + !x25->dest_addr.x25_addr[0] ? "*" : x25->dest_addr.x25_addr, + !x25->source_addr.x25_addr[0] ? "*" : x25->source_addr.x25_addr, + devname, x25->lci & 0x0FFF, x25->state, x25->vs, x25->vr, + x25->va, x25_display_timer(s) / HZ, x25->t2 / HZ, + x25->t21 / HZ, x25->t22 / HZ, x25->t23 / HZ, + sk_wmem_alloc_get(s), + sk_rmem_alloc_get(s), + s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L); +out: + return 0; +} + +static void *x25_seq_forward_start(struct seq_file *seq, loff_t *pos) + __acquires(x25_forward_list_lock) +{ + read_lock_bh(&x25_forward_list_lock); + return seq_list_start_head(&x25_forward_list, *pos); +} + +static void *x25_seq_forward_next(struct seq_file *seq, void *v, loff_t *pos) +{ + return seq_list_next(v, &x25_forward_list, pos); +} + +static void x25_seq_forward_stop(struct seq_file *seq, void *v) + __releases(x25_forward_list_lock) +{ + read_unlock_bh(&x25_forward_list_lock); +} + +static int x25_seq_forward_show(struct seq_file *seq, void *v) +{ + struct x25_forward *f = list_entry(v, struct x25_forward, node); + + if (v == &x25_forward_list) { + seq_printf(seq, "lci dev1 dev2\n"); + goto out; + } + + f = v; + + seq_printf(seq, "%d %-10s %-10s\n", + f->lci, f->dev1->name, f->dev2->name); +out: + return 0; +} + +static const struct seq_operations x25_seq_route_ops = { + .start = x25_seq_route_start, + .next = x25_seq_route_next, + .stop = x25_seq_route_stop, + .show = x25_seq_route_show, +}; + +static const struct seq_operations x25_seq_socket_ops = { + .start = x25_seq_socket_start, + .next = x25_seq_socket_next, + .stop = x25_seq_socket_stop, + .show = x25_seq_socket_show, +}; + +static const struct seq_operations x25_seq_forward_ops = { + .start = x25_seq_forward_start, + .next = x25_seq_forward_next, + .stop = x25_seq_forward_stop, + .show = x25_seq_forward_show, +}; + +int __init x25_proc_init(void) +{ + if (!proc_mkdir("x25", init_net.proc_net)) + return -ENOMEM; + + if (!proc_create_seq("x25/route", 0444, init_net.proc_net, + &x25_seq_route_ops)) + goto out; + + if (!proc_create_seq("x25/socket", 0444, init_net.proc_net, + &x25_seq_socket_ops)) + goto out; + + if (!proc_create_seq("x25/forward", 0444, init_net.proc_net, + &x25_seq_forward_ops)) + goto out; + return 0; + +out: + remove_proc_subtree("x25", init_net.proc_net); + return -ENOMEM; +} + +void __exit x25_proc_exit(void) +{ + remove_proc_subtree("x25", init_net.proc_net); +} + +#else /* CONFIG_PROC_FS */ + +int __init x25_proc_init(void) +{ + return 0; +} + +void __exit x25_proc_exit(void) +{ +} +#endif /* CONFIG_PROC_FS */ diff --git a/net/x25/x25_route.c b/net/x25/x25_route.c new file mode 100644 index 000000000..647f325ed --- /dev/null +++ b/net/x25/x25_route.c @@ -0,0 +1,204 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + */ + +#include <linux/if_arp.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <net/x25.h> + +LIST_HEAD(x25_route_list); +DEFINE_RWLOCK(x25_route_list_lock); + +/* + * Add a new route. + */ +static int x25_add_route(struct x25_address *address, unsigned int sigdigits, + struct net_device *dev) +{ + struct x25_route *rt; + int rc = -EINVAL; + + write_lock_bh(&x25_route_list_lock); + + list_for_each_entry(rt, &x25_route_list, node) { + if (!memcmp(&rt->address, address, sigdigits) && + rt->sigdigits == sigdigits) + goto out; + } + + rt = kmalloc(sizeof(*rt), GFP_ATOMIC); + rc = -ENOMEM; + if (!rt) + goto out; + + strcpy(rt->address.x25_addr, "000000000000000"); + memcpy(rt->address.x25_addr, address->x25_addr, sigdigits); + + rt->sigdigits = sigdigits; + rt->dev = dev; + refcount_set(&rt->refcnt, 1); + + list_add(&rt->node, &x25_route_list); + rc = 0; +out: + write_unlock_bh(&x25_route_list_lock); + return rc; +} + +/** + * __x25_remove_route - remove route from x25_route_list + * @rt: route to remove + * + * Remove route from x25_route_list. If it was there. + * Caller must hold x25_route_list_lock. + */ +static void __x25_remove_route(struct x25_route *rt) +{ + if (rt->node.next) { + list_del(&rt->node); + x25_route_put(rt); + } +} + +static int x25_del_route(struct x25_address *address, unsigned int sigdigits, + struct net_device *dev) +{ + struct x25_route *rt; + int rc = -EINVAL; + + write_lock_bh(&x25_route_list_lock); + + list_for_each_entry(rt, &x25_route_list, node) { + if (!memcmp(&rt->address, address, sigdigits) && + rt->sigdigits == sigdigits && rt->dev == dev) { + __x25_remove_route(rt); + rc = 0; + break; + } + } + + write_unlock_bh(&x25_route_list_lock); + return rc; +} + +/* + * A device has been removed, remove its routes. + */ +void x25_route_device_down(struct net_device *dev) +{ + struct x25_route *rt; + struct list_head *entry, *tmp; + + write_lock_bh(&x25_route_list_lock); + + list_for_each_safe(entry, tmp, &x25_route_list) { + rt = list_entry(entry, struct x25_route, node); + + if (rt->dev == dev) + __x25_remove_route(rt); + } + write_unlock_bh(&x25_route_list_lock); +} + +/* + * Check that the device given is a valid X.25 interface that is "up". + */ +struct net_device *x25_dev_get(char *devname) +{ + struct net_device *dev = dev_get_by_name(&init_net, devname); + + if (dev && (!(dev->flags & IFF_UP) || dev->type != ARPHRD_X25)) { + dev_put(dev); + dev = NULL; + } + + return dev; +} + +/** + * x25_get_route - Find a route given an X.25 address. + * @addr: - address to find a route for + * + * Find a route given an X.25 address. + */ +struct x25_route *x25_get_route(struct x25_address *addr) +{ + struct x25_route *rt, *use = NULL; + + read_lock_bh(&x25_route_list_lock); + + list_for_each_entry(rt, &x25_route_list, node) { + if (!memcmp(&rt->address, addr, rt->sigdigits)) { + if (!use) + use = rt; + else if (rt->sigdigits > use->sigdigits) + use = rt; + } + } + + if (use) + x25_route_hold(use); + + read_unlock_bh(&x25_route_list_lock); + return use; +} + +/* + * Handle the ioctls that control the routing functions. + */ +int x25_route_ioctl(unsigned int cmd, void __user *arg) +{ + struct x25_route_struct rt; + struct net_device *dev; + int rc = -EINVAL; + + if (cmd != SIOCADDRT && cmd != SIOCDELRT) + goto out; + + rc = -EFAULT; + if (copy_from_user(&rt, arg, sizeof(rt))) + goto out; + + rc = -EINVAL; + if (rt.sigdigits > 15) + goto out; + + dev = x25_dev_get(rt.device); + if (!dev) + goto out; + + if (cmd == SIOCADDRT) + rc = x25_add_route(&rt.address, rt.sigdigits, dev); + else + rc = x25_del_route(&rt.address, rt.sigdigits, dev); + dev_put(dev); +out: + return rc; +} + +/* + * Release all memory associated with X.25 routing structures. + */ +void __exit x25_route_free(void) +{ + struct x25_route *rt; + struct list_head *entry, *tmp; + + write_lock_bh(&x25_route_list_lock); + list_for_each_safe(entry, tmp, &x25_route_list) { + rt = list_entry(entry, struct x25_route, node); + __x25_remove_route(rt); + } + write_unlock_bh(&x25_route_list_lock); +} diff --git a/net/x25/x25_subr.c b/net/x25/x25_subr.c new file mode 100644 index 000000000..0285aaa1e --- /dev/null +++ b/net/x25/x25_subr.c @@ -0,0 +1,384 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor Centralised disconnection processing. + * mar/20/00 Daniela Squassoni Disabling/enabling of facilities + * negotiation. + * jun/24/01 Arnaldo C. Melo use skb_queue_purge, cleanups + * apr/04/15 Shaun Pereira Fast select with no + * restriction on response. + */ + +#define pr_fmt(fmt) "X25: " fmt + +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/skbuff.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <net/x25.h> + +/* + * This routine purges all of the queues of frames. + */ +void x25_clear_queues(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + skb_queue_purge(&sk->sk_write_queue); + skb_queue_purge(&x25->ack_queue); + skb_queue_purge(&x25->interrupt_in_queue); + skb_queue_purge(&x25->interrupt_out_queue); + skb_queue_purge(&x25->fragment_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 x25_frames_acked(struct sock *sk, unsigned short nr) +{ + struct sk_buff *skb; + struct x25_sock *x25 = x25_sk(sk); + int modulus = x25->neighbour->extended ? X25_EMODULUS : X25_SMODULUS; + + /* + * Remove all the ack-ed frames from the ack queue. + */ + if (x25->va != nr) + while (skb_peek(&x25->ack_queue) && x25->va != nr) { + skb = skb_dequeue(&x25->ack_queue); + kfree_skb(skb); + x25->va = (x25->va + 1) % modulus; + } +} + +void x25_requeue_frames(struct sock *sk) +{ + struct sk_buff *skb, *skb_prev = NULL; + + /* + * Requeue all the un-ack-ed frames on the output queue to be picked + * up by x25_kick. This arrangement handles the possibility of an empty + * output queue. + */ + while ((skb = skb_dequeue(&x25_sk(sk)->ack_queue)) != NULL) { + if (!skb_prev) + 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 x25_validate_nr(struct sock *sk, unsigned short nr) +{ + struct x25_sock *x25 = x25_sk(sk); + unsigned short vc = x25->va; + int modulus = x25->neighbour->extended ? X25_EMODULUS : X25_SMODULUS; + + while (vc != x25->vs) { + if (nr == vc) + return 1; + vc = (vc + 1) % modulus; + } + + return nr == x25->vs ? 1 : 0; +} + +/* + * This routine is called when the packet layer internally generates a + * control frame. + */ +void x25_write_internal(struct sock *sk, int frametype) +{ + struct x25_sock *x25 = x25_sk(sk); + struct sk_buff *skb; + unsigned char *dptr; + unsigned char facilities[X25_MAX_FAC_LEN]; + unsigned char addresses[1 + X25_ADDR_LEN]; + unsigned char lci1, lci2; + /* + * Default safe frame size. + */ + int len = X25_MAX_L2_LEN + X25_EXT_MIN_LEN; + + /* + * Adjust frame size. + */ + switch (frametype) { + case X25_CALL_REQUEST: + len += 1 + X25_ADDR_LEN + X25_MAX_FAC_LEN + X25_MAX_CUD_LEN; + break; + case X25_CALL_ACCEPTED: /* fast sel with no restr on resp */ + if (x25->facilities.reverse & 0x80) { + len += 1 + X25_MAX_FAC_LEN + X25_MAX_CUD_LEN; + } else { + len += 1 + X25_MAX_FAC_LEN; + } + break; + case X25_CLEAR_REQUEST: + case X25_RESET_REQUEST: + len += 2; + break; + case X25_RR: + case X25_RNR: + case X25_REJ: + case X25_CLEAR_CONFIRMATION: + case X25_INTERRUPT_CONFIRMATION: + case X25_RESET_CONFIRMATION: + break; + default: + pr_err("invalid frame type %02X\n", frametype); + return; + } + + if ((skb = alloc_skb(len, GFP_ATOMIC)) == NULL) + return; + + /* + * Space for Ethernet and 802.2 LLC headers. + */ + skb_reserve(skb, X25_MAX_L2_LEN); + + /* + * Make space for the GFI and LCI, and fill them in. + */ + dptr = skb_put(skb, 2); + + lci1 = (x25->lci >> 8) & 0x0F; + lci2 = (x25->lci >> 0) & 0xFF; + + if (x25->neighbour->extended) { + *dptr++ = lci1 | X25_GFI_EXTSEQ; + *dptr++ = lci2; + } else { + *dptr++ = lci1 | X25_GFI_STDSEQ; + *dptr++ = lci2; + } + + /* + * Now fill in the frame type specific information. + */ + switch (frametype) { + + case X25_CALL_REQUEST: + dptr = skb_put(skb, 1); + *dptr++ = X25_CALL_REQUEST; + len = x25_addr_aton(addresses, &x25->dest_addr, + &x25->source_addr); + skb_put_data(skb, addresses, len); + len = x25_create_facilities(facilities, + &x25->facilities, + &x25->dte_facilities, + x25->neighbour->global_facil_mask); + skb_put_data(skb, facilities, len); + skb_put_data(skb, x25->calluserdata.cuddata, + x25->calluserdata.cudlength); + x25->calluserdata.cudlength = 0; + break; + + case X25_CALL_ACCEPTED: + dptr = skb_put(skb, 2); + *dptr++ = X25_CALL_ACCEPTED; + *dptr++ = 0x00; /* Address lengths */ + len = x25_create_facilities(facilities, + &x25->facilities, + &x25->dte_facilities, + x25->vc_facil_mask); + skb_put_data(skb, facilities, len); + + /* fast select with no restriction on response + allows call user data. Userland must + ensure it is ours and not theirs */ + if(x25->facilities.reverse & 0x80) { + skb_put_data(skb, + x25->calluserdata.cuddata, + x25->calluserdata.cudlength); + } + x25->calluserdata.cudlength = 0; + break; + + case X25_CLEAR_REQUEST: + dptr = skb_put(skb, 3); + *dptr++ = frametype; + *dptr++ = x25->causediag.cause; + *dptr++ = x25->causediag.diagnostic; + break; + + case X25_RESET_REQUEST: + dptr = skb_put(skb, 3); + *dptr++ = frametype; + *dptr++ = 0x00; /* XXX */ + *dptr++ = 0x00; /* XXX */ + break; + + case X25_RR: + case X25_RNR: + case X25_REJ: + if (x25->neighbour->extended) { + dptr = skb_put(skb, 2); + *dptr++ = frametype; + *dptr++ = (x25->vr << 1) & 0xFE; + } else { + dptr = skb_put(skb, 1); + *dptr = frametype; + *dptr++ |= (x25->vr << 5) & 0xE0; + } + break; + + case X25_CLEAR_CONFIRMATION: + case X25_INTERRUPT_CONFIRMATION: + case X25_RESET_CONFIRMATION: + dptr = skb_put(skb, 1); + *dptr = frametype; + break; + } + + x25_transmit_link(skb, x25->neighbour); +} + +/* + * Unpick the contents of the passed X.25 Packet Layer frame. + */ +int x25_decode(struct sock *sk, struct sk_buff *skb, int *ns, int *nr, int *q, + int *d, int *m) +{ + struct x25_sock *x25 = x25_sk(sk); + unsigned char *frame; + + if (!pskb_may_pull(skb, X25_STD_MIN_LEN)) + return X25_ILLEGAL; + frame = skb->data; + + *ns = *nr = *q = *d = *m = 0; + + switch (frame[2]) { + case X25_CALL_REQUEST: + case X25_CALL_ACCEPTED: + case X25_CLEAR_REQUEST: + case X25_CLEAR_CONFIRMATION: + case X25_INTERRUPT: + case X25_INTERRUPT_CONFIRMATION: + case X25_RESET_REQUEST: + case X25_RESET_CONFIRMATION: + case X25_RESTART_REQUEST: + case X25_RESTART_CONFIRMATION: + case X25_REGISTRATION_REQUEST: + case X25_REGISTRATION_CONFIRMATION: + case X25_DIAGNOSTIC: + return frame[2]; + } + + if (x25->neighbour->extended) { + if (frame[2] == X25_RR || + frame[2] == X25_RNR || + frame[2] == X25_REJ) { + if (!pskb_may_pull(skb, X25_EXT_MIN_LEN)) + return X25_ILLEGAL; + frame = skb->data; + + *nr = (frame[3] >> 1) & 0x7F; + return frame[2]; + } + } else { + if ((frame[2] & 0x1F) == X25_RR || + (frame[2] & 0x1F) == X25_RNR || + (frame[2] & 0x1F) == X25_REJ) { + *nr = (frame[2] >> 5) & 0x07; + return frame[2] & 0x1F; + } + } + + if (x25->neighbour->extended) { + if ((frame[2] & 0x01) == X25_DATA) { + if (!pskb_may_pull(skb, X25_EXT_MIN_LEN)) + return X25_ILLEGAL; + frame = skb->data; + + *q = (frame[0] & X25_Q_BIT) == X25_Q_BIT; + *d = (frame[0] & X25_D_BIT) == X25_D_BIT; + *m = (frame[3] & X25_EXT_M_BIT) == X25_EXT_M_BIT; + *nr = (frame[3] >> 1) & 0x7F; + *ns = (frame[2] >> 1) & 0x7F; + return X25_DATA; + } + } else { + if ((frame[2] & 0x01) == X25_DATA) { + *q = (frame[0] & X25_Q_BIT) == X25_Q_BIT; + *d = (frame[0] & X25_D_BIT) == X25_D_BIT; + *m = (frame[2] & X25_STD_M_BIT) == X25_STD_M_BIT; + *nr = (frame[2] >> 5) & 0x07; + *ns = (frame[2] >> 1) & 0x07; + return X25_DATA; + } + } + + pr_debug("invalid PLP frame %3ph\n", frame); + + return X25_ILLEGAL; +} + +void x25_disconnect(struct sock *sk, int reason, unsigned char cause, + unsigned char diagnostic) +{ + struct x25_sock *x25 = x25_sk(sk); + + x25_clear_queues(sk); + x25_stop_timer(sk); + + x25->lci = 0; + x25->state = X25_STATE_0; + + x25->causediag.cause = cause; + x25->causediag.diagnostic = diagnostic; + + 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); + } + if (x25->neighbour) { + read_lock_bh(&x25_list_lock); + x25_neigh_put(x25->neighbour); + x25->neighbour = NULL; + read_unlock_bh(&x25_list_lock); + } +} + +/* + * Clear an own-rx-busy condition and tell the peer about this, provided + * that there is a significant amount of free receive buffer space available. + */ +void x25_check_rbuf(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf >> 1) && + (x25->condition & X25_COND_OWN_RX_BUSY)) { + x25->condition &= ~X25_COND_OWN_RX_BUSY; + x25->condition &= ~X25_COND_ACK_PENDING; + x25->vl = x25->vr; + x25_write_internal(sk, X25_RR); + x25_stop_timer(sk); + } +} diff --git a/net/x25/x25_timer.c b/net/x25/x25_timer.c new file mode 100644 index 000000000..9376365cd --- /dev/null +++ b/net/x25/x25_timer.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * X.25 Packet Layer release 002 + * + * This is ALPHA test software. This code may break your machine, + * randomly fail to work with new releases, misbehave and/or generally + * screw up. It might even work. + * + * This code REQUIRES 2.1.15 or higher + * + * History + * X.25 001 Jonathan Naylor Started coding. + * X.25 002 Jonathan Naylor New timer architecture. + * Centralised disconnection processing. + */ + +#include <linux/errno.h> +#include <linux/jiffies.h> +#include <linux/timer.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <net/x25.h> + +static void x25_heartbeat_expiry(struct timer_list *t); +static void x25_timer_expiry(struct timer_list *t); + +void x25_init_timers(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + timer_setup(&x25->timer, x25_timer_expiry, 0); + + /* initialized by sock_init_data */ + sk->sk_timer.function = x25_heartbeat_expiry; +} + +void x25_start_heartbeat(struct sock *sk) +{ + mod_timer(&sk->sk_timer, jiffies + 5 * HZ); +} + +void x25_stop_heartbeat(struct sock *sk) +{ + del_timer(&sk->sk_timer); +} + +void x25_start_t2timer(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + mod_timer(&x25->timer, jiffies + x25->t2); +} + +void x25_start_t21timer(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + mod_timer(&x25->timer, jiffies + x25->t21); +} + +void x25_start_t22timer(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + mod_timer(&x25->timer, jiffies + x25->t22); +} + +void x25_start_t23timer(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + mod_timer(&x25->timer, jiffies + x25->t23); +} + +void x25_stop_timer(struct sock *sk) +{ + del_timer(&x25_sk(sk)->timer); +} + +unsigned long x25_display_timer(struct sock *sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + if (!timer_pending(&x25->timer)) + return 0; + + return x25->timer.expires - jiffies; +} + +static void x25_heartbeat_expiry(struct timer_list *t) +{ + struct sock *sk = from_timer(sk, t, sk_timer); + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) /* can currently only occur in state 3 */ + goto restart_heartbeat; + + switch (x25_sk(sk)->state) { + + case X25_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))) { + bh_unlock_sock(sk); + x25_destroy_socket_from_timer(sk); + return; + } + break; + + case X25_STATE_3: + /* + * Check for the state of the receive buffer. + */ + x25_check_rbuf(sk); + break; + } +restart_heartbeat: + x25_start_heartbeat(sk); + bh_unlock_sock(sk); +} + +/* + * Timer has expired, it may have been T2, T21, T22, or T23. We can tell + * by the state machine state. + */ +static inline void x25_do_timer_expiry(struct sock * sk) +{ + struct x25_sock *x25 = x25_sk(sk); + + switch (x25->state) { + + case X25_STATE_3: /* T2 */ + if (x25->condition & X25_COND_ACK_PENDING) { + x25->condition &= ~X25_COND_ACK_PENDING; + x25_enquiry_response(sk); + } + break; + + case X25_STATE_1: /* T21 */ + case X25_STATE_4: /* T22 */ + x25_write_internal(sk, X25_CLEAR_REQUEST); + x25->state = X25_STATE_2; + x25_start_t23timer(sk); + break; + + case X25_STATE_2: /* T23 */ + x25_disconnect(sk, ETIMEDOUT, 0, 0); + break; + } +} + +static void x25_timer_expiry(struct timer_list *t) +{ + struct x25_sock *x25 = from_timer(x25, t, timer); + struct sock *sk = &x25->sk; + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */ + if (x25_sk(sk)->state == X25_STATE_3) + x25_start_t2timer(sk); + } else + x25_do_timer_expiry(sk); + bh_unlock_sock(sk); +} |