diff options
Diffstat (limited to 'net/phonet/socket.c')
-rw-r--r-- | net/phonet/socket.c | 775 |
1 files changed, 775 insertions, 0 deletions
diff --git a/net/phonet/socket.c b/net/phonet/socket.c new file mode 100644 index 000000000..2599235d5 --- /dev/null +++ b/net/phonet/socket.c @@ -0,0 +1,775 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * File: socket.c + * + * Phonet sockets + * + * Copyright (C) 2008 Nokia Corporation. + * + * Authors: Sakari Ailus <sakari.ailus@nokia.com> + * RĂ©mi Denis-Courmont + */ + +#include <linux/gfp.h> +#include <linux/kernel.h> +#include <linux/net.h> +#include <linux/poll.h> +#include <linux/sched/signal.h> + +#include <net/sock.h> +#include <net/tcp_states.h> + +#include <linux/phonet.h> +#include <linux/export.h> +#include <net/phonet/phonet.h> +#include <net/phonet/pep.h> +#include <net/phonet/pn_dev.h> + +static int pn_socket_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + + if (sk) { + sock->sk = NULL; + sk->sk_prot->close(sk, 0); + } + return 0; +} + +#define PN_HASHSIZE 16 +#define PN_HASHMASK (PN_HASHSIZE-1) + + +static struct { + struct hlist_head hlist[PN_HASHSIZE]; + struct mutex lock; +} pnsocks; + +void __init pn_sock_init(void) +{ + unsigned int i; + + for (i = 0; i < PN_HASHSIZE; i++) + INIT_HLIST_HEAD(pnsocks.hlist + i); + mutex_init(&pnsocks.lock); +} + +static struct hlist_head *pn_hash_list(u16 obj) +{ + return pnsocks.hlist + (obj & PN_HASHMASK); +} + +/* + * Find address based on socket address, match only certain fields. + * Also grab sock if it was found. Remember to sock_put it later. + */ +struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn) +{ + struct sock *sknode; + struct sock *rval = NULL; + u16 obj = pn_sockaddr_get_object(spn); + u8 res = spn->spn_resource; + struct hlist_head *hlist = pn_hash_list(obj); + + rcu_read_lock(); + sk_for_each_rcu(sknode, hlist) { + struct pn_sock *pn = pn_sk(sknode); + BUG_ON(!pn->sobject); /* unbound socket */ + + if (!net_eq(sock_net(sknode), net)) + continue; + if (pn_port(obj)) { + /* Look up socket by port */ + if (pn_port(pn->sobject) != pn_port(obj)) + continue; + } else { + /* If port is zero, look up by resource */ + if (pn->resource != res) + continue; + } + if (pn_addr(pn->sobject) && + pn_addr(pn->sobject) != pn_addr(obj)) + continue; + + rval = sknode; + sock_hold(sknode); + break; + } + rcu_read_unlock(); + + return rval; +} + +/* Deliver a broadcast packet (only in bottom-half) */ +void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb) +{ + struct hlist_head *hlist = pnsocks.hlist; + unsigned int h; + + rcu_read_lock(); + for (h = 0; h < PN_HASHSIZE; h++) { + struct sock *sknode; + + sk_for_each(sknode, hlist) { + struct sk_buff *clone; + + if (!net_eq(sock_net(sknode), net)) + continue; + if (!sock_flag(sknode, SOCK_BROADCAST)) + continue; + + clone = skb_clone(skb, GFP_ATOMIC); + if (clone) { + sock_hold(sknode); + sk_receive_skb(sknode, clone, 0); + } + } + hlist++; + } + rcu_read_unlock(); +} + +int pn_sock_hash(struct sock *sk) +{ + struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject); + + mutex_lock(&pnsocks.lock); + sk_add_node_rcu(sk, hlist); + mutex_unlock(&pnsocks.lock); + + return 0; +} +EXPORT_SYMBOL(pn_sock_hash); + +void pn_sock_unhash(struct sock *sk) +{ + mutex_lock(&pnsocks.lock); + sk_del_node_init_rcu(sk); + mutex_unlock(&pnsocks.lock); + pn_sock_unbind_all_res(sk); + synchronize_rcu(); +} +EXPORT_SYMBOL(pn_sock_unhash); + +static DEFINE_MUTEX(port_mutex); + +static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len) +{ + struct sock *sk = sock->sk; + struct pn_sock *pn = pn_sk(sk); + struct sockaddr_pn *spn = (struct sockaddr_pn *)addr; + int err; + u16 handle; + u8 saddr; + + if (sk->sk_prot->bind) + return sk->sk_prot->bind(sk, addr, len); + + if (len < sizeof(struct sockaddr_pn)) + return -EINVAL; + if (spn->spn_family != AF_PHONET) + return -EAFNOSUPPORT; + + handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr); + saddr = pn_addr(handle); + if (saddr && phonet_address_lookup(sock_net(sk), saddr)) + return -EADDRNOTAVAIL; + + lock_sock(sk); + if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) { + err = -EINVAL; /* attempt to rebind */ + goto out; + } + WARN_ON(sk_hashed(sk)); + mutex_lock(&port_mutex); + err = sk->sk_prot->get_port(sk, pn_port(handle)); + if (err) + goto out_port; + + /* get_port() sets the port, bind() sets the address if applicable */ + pn->sobject = pn_object(saddr, pn_port(pn->sobject)); + pn->resource = spn->spn_resource; + + /* Enable RX on the socket */ + err = sk->sk_prot->hash(sk); +out_port: + mutex_unlock(&port_mutex); +out: + release_sock(sk); + return err; +} + +static int pn_socket_autobind(struct socket *sock) +{ + struct sockaddr_pn sa; + int err; + + memset(&sa, 0, sizeof(sa)); + sa.spn_family = AF_PHONET; + err = pn_socket_bind(sock, (struct sockaddr *)&sa, + sizeof(struct sockaddr_pn)); + if (err != -EINVAL) + return err; + BUG_ON(!pn_port(pn_sk(sock->sk)->sobject)); + return 0; /* socket was already bound */ +} + +static int pn_socket_connect(struct socket *sock, struct sockaddr *addr, + int len, int flags) +{ + struct sock *sk = sock->sk; + struct pn_sock *pn = pn_sk(sk); + struct sockaddr_pn *spn = (struct sockaddr_pn *)addr; + struct task_struct *tsk = current; + long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); + int err; + + if (pn_socket_autobind(sock)) + return -ENOBUFS; + if (len < sizeof(struct sockaddr_pn)) + return -EINVAL; + if (spn->spn_family != AF_PHONET) + return -EAFNOSUPPORT; + + lock_sock(sk); + + switch (sock->state) { + case SS_UNCONNECTED: + if (sk->sk_state != TCP_CLOSE) { + err = -EISCONN; + goto out; + } + break; + case SS_CONNECTING: + err = -EALREADY; + goto out; + default: + err = -EISCONN; + goto out; + } + + pn->dobject = pn_sockaddr_get_object(spn); + pn->resource = pn_sockaddr_get_resource(spn); + sock->state = SS_CONNECTING; + + err = sk->sk_prot->connect(sk, addr, len); + if (err) { + sock->state = SS_UNCONNECTED; + pn->dobject = 0; + goto out; + } + + while (sk->sk_state == TCP_SYN_SENT) { + DEFINE_WAIT(wait); + + if (!timeo) { + err = -EINPROGRESS; + goto out; + } + if (signal_pending(tsk)) { + err = sock_intr_errno(timeo); + goto out; + } + + prepare_to_wait_exclusive(sk_sleep(sk), &wait, + TASK_INTERRUPTIBLE); + release_sock(sk); + timeo = schedule_timeout(timeo); + lock_sock(sk); + finish_wait(sk_sleep(sk), &wait); + } + + if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) + err = 0; + else if (sk->sk_state == TCP_CLOSE_WAIT) + err = -ECONNRESET; + else + err = -ECONNREFUSED; + sock->state = err ? SS_UNCONNECTED : SS_CONNECTED; +out: + release_sock(sk); + return err; +} + +static int pn_socket_accept(struct socket *sock, struct socket *newsock, + int flags, bool kern) +{ + struct sock *sk = sock->sk; + struct sock *newsk; + int err; + + if (unlikely(sk->sk_state != TCP_LISTEN)) + return -EINVAL; + + newsk = sk->sk_prot->accept(sk, flags, &err, kern); + if (!newsk) + return err; + + lock_sock(newsk); + sock_graft(newsk, newsock); + newsock->state = SS_CONNECTED; + release_sock(newsk); + return 0; +} + +static int pn_socket_getname(struct socket *sock, struct sockaddr *addr, + int peer) +{ + struct sock *sk = sock->sk; + struct pn_sock *pn = pn_sk(sk); + + memset(addr, 0, sizeof(struct sockaddr_pn)); + addr->sa_family = AF_PHONET; + if (!peer) /* Race with bind() here is userland's problem. */ + pn_sockaddr_set_object((struct sockaddr_pn *)addr, + pn->sobject); + + return sizeof(struct sockaddr_pn); +} + +static __poll_t pn_socket_poll(struct file *file, struct socket *sock, + poll_table *wait) +{ + struct sock *sk = sock->sk; + struct pep_sock *pn = pep_sk(sk); + __poll_t mask = 0; + + poll_wait(file, sk_sleep(sk), wait); + + if (sk->sk_state == TCP_CLOSE) + return EPOLLERR; + if (!skb_queue_empty_lockless(&sk->sk_receive_queue)) + mask |= EPOLLIN | EPOLLRDNORM; + if (!skb_queue_empty_lockless(&pn->ctrlreq_queue)) + mask |= EPOLLPRI; + if (!mask && sk->sk_state == TCP_CLOSE_WAIT) + return EPOLLHUP; + + if (sk->sk_state == TCP_ESTABLISHED && + refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf && + atomic_read(&pn->tx_credits)) + mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND; + + return mask; +} + +static int pn_socket_ioctl(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + struct sock *sk = sock->sk; + struct pn_sock *pn = pn_sk(sk); + + if (cmd == SIOCPNGETOBJECT) { + struct net_device *dev; + u16 handle; + u8 saddr; + + if (get_user(handle, (__u16 __user *)arg)) + return -EFAULT; + + lock_sock(sk); + if (sk->sk_bound_dev_if) + dev = dev_get_by_index(sock_net(sk), + sk->sk_bound_dev_if); + else + dev = phonet_device_get(sock_net(sk)); + if (dev && (dev->flags & IFF_UP)) + saddr = phonet_address_get(dev, pn_addr(handle)); + else + saddr = PN_NO_ADDR; + release_sock(sk); + + if (dev) + dev_put(dev); + if (saddr == PN_NO_ADDR) + return -EHOSTUNREACH; + + handle = pn_object(saddr, pn_port(pn->sobject)); + return put_user(handle, (__u16 __user *)arg); + } + + return sk->sk_prot->ioctl(sk, cmd, arg); +} + +static int pn_socket_listen(struct socket *sock, int backlog) +{ + struct sock *sk = sock->sk; + int err = 0; + + if (pn_socket_autobind(sock)) + return -ENOBUFS; + + lock_sock(sk); + if (sock->state != SS_UNCONNECTED) { + err = -EINVAL; + goto out; + } + + if (sk->sk_state != TCP_LISTEN) { + sk->sk_state = TCP_LISTEN; + sk->sk_ack_backlog = 0; + } + sk->sk_max_ack_backlog = backlog; +out: + release_sock(sk); + return err; +} + +static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m, + size_t total_len) +{ + struct sock *sk = sock->sk; + + if (pn_socket_autobind(sock)) + return -EAGAIN; + + return sk->sk_prot->sendmsg(sk, m, total_len); +} + +const struct proto_ops phonet_dgram_ops = { + .family = AF_PHONET, + .owner = THIS_MODULE, + .release = pn_socket_release, + .bind = pn_socket_bind, + .connect = sock_no_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = pn_socket_getname, + .poll = datagram_poll, + .ioctl = pn_socket_ioctl, + .listen = sock_no_listen, + .shutdown = sock_no_shutdown, + .sendmsg = pn_socket_sendmsg, + .recvmsg = sock_common_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; + +const struct proto_ops phonet_stream_ops = { + .family = AF_PHONET, + .owner = THIS_MODULE, + .release = pn_socket_release, + .bind = pn_socket_bind, + .connect = pn_socket_connect, + .socketpair = sock_no_socketpair, + .accept = pn_socket_accept, + .getname = pn_socket_getname, + .poll = pn_socket_poll, + .ioctl = pn_socket_ioctl, + .listen = pn_socket_listen, + .shutdown = sock_no_shutdown, + .setsockopt = sock_common_setsockopt, + .getsockopt = sock_common_getsockopt, + .sendmsg = pn_socket_sendmsg, + .recvmsg = sock_common_recvmsg, + .mmap = sock_no_mmap, + .sendpage = sock_no_sendpage, +}; +EXPORT_SYMBOL(phonet_stream_ops); + +/* allocate port for a socket */ +int pn_sock_get_port(struct sock *sk, unsigned short sport) +{ + static int port_cur; + struct net *net = sock_net(sk); + struct pn_sock *pn = pn_sk(sk); + struct sockaddr_pn try_sa; + struct sock *tmpsk; + + memset(&try_sa, 0, sizeof(struct sockaddr_pn)); + try_sa.spn_family = AF_PHONET; + WARN_ON(!mutex_is_locked(&port_mutex)); + if (!sport) { + /* search free port */ + int port, pmin, pmax; + + phonet_get_local_port_range(&pmin, &pmax); + for (port = pmin; port <= pmax; port++) { + port_cur++; + if (port_cur < pmin || port_cur > pmax) + port_cur = pmin; + + pn_sockaddr_set_port(&try_sa, port_cur); + tmpsk = pn_find_sock_by_sa(net, &try_sa); + if (tmpsk == NULL) { + sport = port_cur; + goto found; + } else + sock_put(tmpsk); + } + } else { + /* try to find specific port */ + pn_sockaddr_set_port(&try_sa, sport); + tmpsk = pn_find_sock_by_sa(net, &try_sa); + if (tmpsk == NULL) + /* No sock there! We can use that port... */ + goto found; + else + sock_put(tmpsk); + } + /* the port must be in use already */ + return -EADDRINUSE; + +found: + pn->sobject = pn_object(pn_addr(pn->sobject), sport); + return 0; +} +EXPORT_SYMBOL(pn_sock_get_port); + +#ifdef CONFIG_PROC_FS +static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos) +{ + struct net *net = seq_file_net(seq); + struct hlist_head *hlist = pnsocks.hlist; + struct sock *sknode; + unsigned int h; + + for (h = 0; h < PN_HASHSIZE; h++) { + sk_for_each_rcu(sknode, hlist) { + if (!net_eq(net, sock_net(sknode))) + continue; + if (!pos) + return sknode; + pos--; + } + hlist++; + } + return NULL; +} + +static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk) +{ + struct net *net = seq_file_net(seq); + + do + sk = sk_next(sk); + while (sk && !net_eq(net, sock_net(sk))); + + return sk; +} + +static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos) + __acquires(rcu) +{ + rcu_read_lock(); + return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; +} + +static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct sock *sk; + + if (v == SEQ_START_TOKEN) + sk = pn_sock_get_idx(seq, 0); + else + sk = pn_sock_get_next(seq, v); + (*pos)++; + return sk; +} + +static void pn_sock_seq_stop(struct seq_file *seq, void *v) + __releases(rcu) +{ + rcu_read_unlock(); +} + +static int pn_sock_seq_show(struct seq_file *seq, void *v) +{ + seq_setwidth(seq, 127); + if (v == SEQ_START_TOKEN) + seq_puts(seq, "pt loc rem rs st tx_queue rx_queue " + " uid inode ref pointer drops"); + else { + struct sock *sk = v; + struct pn_sock *pn = pn_sk(sk); + + seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu " + "%d %pK %u", + sk->sk_protocol, pn->sobject, pn->dobject, + pn->resource, sk->sk_state, + sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk), + refcount_read(&sk->sk_refcnt), sk, + atomic_read(&sk->sk_drops)); + } + seq_pad(seq, '\n'); + return 0; +} + +const struct seq_operations pn_sock_seq_ops = { + .start = pn_sock_seq_start, + .next = pn_sock_seq_next, + .stop = pn_sock_seq_stop, + .show = pn_sock_seq_show, +}; +#endif + +static struct { + struct sock *sk[256]; +} pnres; + +/* + * Find and hold socket based on resource. + */ +struct sock *pn_find_sock_by_res(struct net *net, u8 res) +{ + struct sock *sk; + + if (!net_eq(net, &init_net)) + return NULL; + + rcu_read_lock(); + sk = rcu_dereference(pnres.sk[res]); + if (sk) + sock_hold(sk); + rcu_read_unlock(); + return sk; +} + +static DEFINE_MUTEX(resource_mutex); + +int pn_sock_bind_res(struct sock *sk, u8 res) +{ + int ret = -EADDRINUSE; + + if (!net_eq(sock_net(sk), &init_net)) + return -ENOIOCTLCMD; + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + if (pn_socket_autobind(sk->sk_socket)) + return -EAGAIN; + + mutex_lock(&resource_mutex); + if (pnres.sk[res] == NULL) { + sock_hold(sk); + rcu_assign_pointer(pnres.sk[res], sk); + ret = 0; + } + mutex_unlock(&resource_mutex); + return ret; +} + +int pn_sock_unbind_res(struct sock *sk, u8 res) +{ + int ret = -ENOENT; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + mutex_lock(&resource_mutex); + if (pnres.sk[res] == sk) { + RCU_INIT_POINTER(pnres.sk[res], NULL); + ret = 0; + } + mutex_unlock(&resource_mutex); + + if (ret == 0) { + synchronize_rcu(); + sock_put(sk); + } + return ret; +} + +void pn_sock_unbind_all_res(struct sock *sk) +{ + unsigned int res, match = 0; + + mutex_lock(&resource_mutex); + for (res = 0; res < 256; res++) { + if (pnres.sk[res] == sk) { + RCU_INIT_POINTER(pnres.sk[res], NULL); + match++; + } + } + mutex_unlock(&resource_mutex); + + while (match > 0) { + __sock_put(sk); + match--; + } + /* Caller is responsible for RCU sync before final sock_put() */ +} + +#ifdef CONFIG_PROC_FS +static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos) +{ + struct net *net = seq_file_net(seq); + unsigned int i; + + if (!net_eq(net, &init_net)) + return NULL; + + for (i = 0; i < 256; i++) { + if (pnres.sk[i] == NULL) + continue; + if (!pos) + return pnres.sk + i; + pos--; + } + return NULL; +} + +static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk) +{ + struct net *net = seq_file_net(seq); + unsigned int i; + + BUG_ON(!net_eq(net, &init_net)); + + for (i = (sk - pnres.sk) + 1; i < 256; i++) + if (pnres.sk[i]) + return pnres.sk + i; + return NULL; +} + +static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos) + __acquires(resource_mutex) +{ + mutex_lock(&resource_mutex); + return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; +} + +static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos) +{ + struct sock **sk; + + if (v == SEQ_START_TOKEN) + sk = pn_res_get_idx(seq, 0); + else + sk = pn_res_get_next(seq, v); + (*pos)++; + return sk; +} + +static void pn_res_seq_stop(struct seq_file *seq, void *v) + __releases(resource_mutex) +{ + mutex_unlock(&resource_mutex); +} + +static int pn_res_seq_show(struct seq_file *seq, void *v) +{ + seq_setwidth(seq, 63); + if (v == SEQ_START_TOKEN) + seq_puts(seq, "rs uid inode"); + else { + struct sock **psk = v; + struct sock *sk = *psk; + + seq_printf(seq, "%02X %5u %lu", + (int) (psk - pnres.sk), + from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)), + sock_i_ino(sk)); + } + seq_pad(seq, '\n'); + return 0; +} + +const struct seq_operations pn_res_seq_ops = { + .start = pn_res_seq_start, + .next = pn_res_seq_next, + .stop = pn_res_seq_stop, + .show = pn_res_seq_show, +}; +#endif |