// 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); 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