/* AF_RXRPC implementation * * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/module.h> #include <linux/net.h> #include <linux/skbuff.h> #include <linux/poll.h> #include <linux/proc_fs.h> #include <linux/key-type.h> #include <net/net_namespace.h> #include <net/sock.h> #include <net/af_rxrpc.h> #include "ar-internal.h" MODULE_DESCRIPTION("RxRPC network protocol"); MODULE_AUTHOR("Red Hat, Inc."); MODULE_LICENSE("GPL"); MODULE_ALIAS_NETPROTO(PF_RXRPC); unsigned rxrpc_debug; // = RXRPC_DEBUG_KPROTO; module_param_named(debug, rxrpc_debug, uint, S_IWUSR | S_IRUGO); MODULE_PARM_DESC(rxrpc_debug, "RxRPC debugging mask"); static int sysctl_rxrpc_max_qlen __read_mostly = 10; static struct proto rxrpc_proto; static const struct proto_ops rxrpc_rpc_ops; /* local epoch for detecting local-end reset */ __be32 rxrpc_epoch; /* current debugging ID */ atomic_t rxrpc_debug_id; /* count of skbs currently in use */ atomic_t rxrpc_n_skbs; struct workqueue_struct *rxrpc_workqueue; static void rxrpc_sock_destructor(struct sock *); /* * see if an RxRPC socket is currently writable */ static inline int rxrpc_writable(struct sock *sk) { return atomic_read(&sk->sk_wmem_alloc) < (size_t) sk->sk_sndbuf; } /* * wait for write bufferage to become available */ static void rxrpc_write_space(struct sock *sk) { _enter("%p", sk); read_lock(&sk->sk_callback_lock); if (rxrpc_writable(sk)) { if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep); sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); } read_unlock(&sk->sk_callback_lock); } /* * validate an RxRPC address */ static int rxrpc_validate_address(struct rxrpc_sock *rx, struct sockaddr_rxrpc *srx, int len) { if (len < sizeof(struct sockaddr_rxrpc)) return -EINVAL; if (srx->srx_family != AF_RXRPC) return -EAFNOSUPPORT; if (srx->transport_type != SOCK_DGRAM) return -ESOCKTNOSUPPORT; len -= offsetof(struct sockaddr_rxrpc, transport); if (srx->transport_len < sizeof(sa_family_t) || srx->transport_len > len) return -EINVAL; if (srx->transport.family != rx->proto) return -EAFNOSUPPORT; switch (srx->transport.family) { case AF_INET: _debug("INET: %x @ %u.%u.%u.%u", ntohs(srx->transport.sin.sin_port), NIPQUAD(srx->transport.sin.sin_addr)); if (srx->transport_len > 8) memset((void *)&srx->transport + 8, 0, srx->transport_len - 8); break; case AF_INET6: default: return -EAFNOSUPPORT; } return 0; } /* * bind a local address to an RxRPC socket */ static int rxrpc_bind(struct socket *sock, struct sockaddr *saddr, int len) { struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) saddr; struct sock *sk = sock->sk; struct rxrpc_local *local; struct rxrpc_sock *rx = rxrpc_sk(sk), *prx; __be16 service_id; int ret; _enter("%p,%p,%d", rx, saddr, len); ret = rxrpc_validate_address(rx, srx, len); if (ret < 0) goto error; lock_sock(&rx->sk); if (rx->sk.sk_state != RXRPC_UNCONNECTED) { ret = -EINVAL; goto error_unlock; } memcpy(&rx->srx, srx, sizeof(rx->srx)); /* find a local transport endpoint if we don't have one already */ local = rxrpc_lookup_local(&rx->srx); if (IS_ERR(local)) { ret = PTR_ERR(local); goto error_unlock; } rx->local = local; if (srx->srx_service) { service_id = htons(srx->srx_service); write_lock_bh(&local->services_lock); list_for_each_entry(prx, &local->services, listen_link) { if (prx->service_id == service_id) goto service_in_use; } rx->service_id = service_id; list_add_tail(&rx->listen_link, &local->services); write_unlock_bh(&local->services_lock); rx->sk.sk_state = RXRPC_SERVER_BOUND; } else { rx->sk.sk_state = RXRPC_CLIENT_BOUND; } release_sock(&rx->sk); _leave(" = 0"); return 0; service_in_use: ret = -EADDRINUSE; write_unlock_bh(&local->services_lock); error_unlock: release_sock(&rx->sk); error: _leave(" = %d", ret); return ret; } /* * set the number of pending calls permitted on a listening socket */ static int rxrpc_listen(struct socket *sock, int backlog) { struct sock *sk = sock->sk; struct rxrpc_sock *rx = rxrpc_sk(sk); int ret; _enter("%p,%d", rx, backlog); lock_sock(&rx->sk); switch (rx->sk.sk_state) { case RXRPC_UNCONNECTED: ret = -EADDRNOTAVAIL; break; case RXRPC_CLIENT_BOUND: case RXRPC_CLIENT_CONNECTED: default: ret = -EBUSY; break; case RXRPC_SERVER_BOUND: ASSERT(rx->local != NULL); sk->sk_max_ack_backlog = backlog; rx->sk.sk_state = RXRPC_SERVER_LISTENING; ret = 0; break; } release_sock(&rx->sk); _leave(" = %d", ret); return ret; } /* * find a transport by address */ static struct rxrpc_transport *rxrpc_name_to_transport(struct socket *sock, struct sockaddr *addr, int addr_len, int flags, gfp_t gfp) { struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr; struct rxrpc_transport *trans; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); struct rxrpc_peer *peer; _enter("%p,%p,%d,%d", rx, addr, addr_len, flags); ASSERT(rx->local != NULL); ASSERT(rx->sk.sk_state > RXRPC_UNCONNECTED); if (rx->srx.transport_type != srx->transport_type) return ERR_PTR(-ESOCKTNOSUPPORT); if (rx->srx.transport.family != srx->transport.family) return ERR_PTR(-EAFNOSUPPORT); /* find a remote transport endpoint from the local one */ peer = rxrpc_get_peer(srx, gfp); if (IS_ERR(peer)) return ERR_CAST(peer); /* find a transport */ trans = rxrpc_get_transport(rx->local, peer, gfp); rxrpc_put_peer(peer); _leave(" = %p", trans); return trans; } /** * rxrpc_kernel_begin_call - Allow a kernel service to begin a call * @sock: The socket on which to make the call * @srx: The address of the peer to contact (defaults to socket setting) * @key: The security context to use (defaults to socket setting) * @user_call_ID: The ID to use * * Allow a kernel service to begin a call on the nominated socket. This just * sets up all the internal tracking structures and allocates connection and * call IDs as appropriate. The call to be used is returned. * * The default socket destination address and security may be overridden by * supplying @srx and @key. */ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock, struct sockaddr_rxrpc *srx, struct key *key, unsigned long user_call_ID, gfp_t gfp) { struct rxrpc_conn_bundle *bundle; struct rxrpc_transport *trans; struct rxrpc_call *call; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); __be16 service_id; _enter(",,%x,%lx", key_serial(key), user_call_ID); lock_sock(&rx->sk); if (srx) { trans = rxrpc_name_to_transport(sock, (struct sockaddr *) srx, sizeof(*srx), 0, gfp); if (IS_ERR(trans)) { call = ERR_CAST(trans); trans = NULL; goto out; } } else { trans = rx->trans; if (!trans) { call = ERR_PTR(-ENOTCONN); goto out; } atomic_inc(&trans->usage); } service_id = rx->service_id; if (srx) service_id = htons(srx->srx_service); if (!key) key = rx->key; if (key && !key->payload.data) key = NULL; /* a no-security key */ bundle = rxrpc_get_bundle(rx, trans, key, service_id, gfp); if (IS_ERR(bundle)) { call = ERR_CAST(bundle); goto out; } call = rxrpc_get_client_call(rx, trans, bundle, user_call_ID, true, gfp); rxrpc_put_bundle(trans, bundle); out: rxrpc_put_transport(trans); release_sock(&rx->sk); _leave(" = %p", call); return call; } EXPORT_SYMBOL(rxrpc_kernel_begin_call); /** * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using * @call: The call to end * * Allow a kernel service to end a call it was using. The call must be * complete before this is called (the call should be aborted if necessary). */ void rxrpc_kernel_end_call(struct rxrpc_call *call) { _enter("%d{%d}", call->debug_id, atomic_read(&call->usage)); rxrpc_remove_user_ID(call->socket, call); rxrpc_put_call(call); } EXPORT_SYMBOL(rxrpc_kernel_end_call); /** * rxrpc_kernel_intercept_rx_messages - Intercept received RxRPC messages * @sock: The socket to intercept received messages on * @interceptor: The function to pass the messages to * * Allow a kernel service to intercept messages heading for the Rx queue on an * RxRPC socket. They get passed to the specified function instead. * @interceptor should free the socket buffers it is given. @interceptor is * called with the socket receive queue spinlock held and softirqs disabled - * this ensures that the messages will be delivered in the right order. */ void rxrpc_kernel_intercept_rx_messages(struct socket *sock, rxrpc_interceptor_t interceptor) { struct rxrpc_sock *rx = rxrpc_sk(sock->sk); _enter(""); rx->interceptor = interceptor; } EXPORT_SYMBOL(rxrpc_kernel_intercept_rx_messages); /* * connect an RxRPC socket * - this just targets it at a specific destination; no actual connection * negotiation takes place */ static int rxrpc_connect(struct socket *sock, struct sockaddr *addr, int addr_len, int flags) { struct sockaddr_rxrpc *srx = (struct sockaddr_rxrpc *) addr; struct sock *sk = sock->sk; struct rxrpc_transport *trans; struct rxrpc_local *local; struct rxrpc_sock *rx = rxrpc_sk(sk); int ret; _enter("%p,%p,%d,%d", rx, addr, addr_len, flags); ret = rxrpc_validate_address(rx, srx, addr_len); if (ret < 0) { _leave(" = %d [bad addr]", ret); return ret; } lock_sock(&rx->sk); switch (rx->sk.sk_state) { case RXRPC_UNCONNECTED: /* find a local transport endpoint if we don't have one already */ ASSERTCMP(rx->local, ==, NULL); rx->srx.srx_family = AF_RXRPC; rx->srx.srx_service = 0; rx->srx.transport_type = srx->transport_type; rx->srx.transport_len = sizeof(sa_family_t); rx->srx.transport.family = srx->transport.family; local = rxrpc_lookup_local(&rx->srx); if (IS_ERR(local)) { release_sock(&rx->sk); return PTR_ERR(local); } rx->local = local; rx->sk.sk_state = RXRPC_CLIENT_BOUND; case RXRPC_CLIENT_BOUND: break; case RXRPC_CLIENT_CONNECTED: release_sock(&rx->sk); return -EISCONN; default: release_sock(&rx->sk); return -EBUSY; /* server sockets can't connect as well */ } trans = rxrpc_name_to_transport(sock, addr, addr_len, flags, GFP_KERNEL); if (IS_ERR(trans)) { release_sock(&rx->sk); _leave(" = %ld", PTR_ERR(trans)); return PTR_ERR(trans); } rx->trans = trans; rx->service_id = htons(srx->srx_service); rx->sk.sk_state = RXRPC_CLIENT_CONNECTED; release_sock(&rx->sk); return 0; } /* * send a message through an RxRPC socket * - in a client this does a number of things: * - finds/sets up a connection for the security specified (if any) * - initiates a call (ID in control data) * - ends the request phase of a call (if MSG_MORE is not set) * - sends a call data packet * - may send an abort (abort code in control data) */ static int rxrpc_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t len) { struct rxrpc_transport *trans; struct rxrpc_sock *rx = rxrpc_sk(sock->sk); int ret; _enter(",{%d},,%zu", rx->sk.sk_state, len); if (m->msg_flags & MSG_OOB) return -EOPNOTSUPP; if (m->msg_name) { ret = rxrpc_validate_address(rx, m->msg_name, m->msg_namelen); if (ret < 0) { _leave(" = %d [bad addr]", ret); return ret; } } trans = NULL; lock_sock(&rx->sk); if (m->msg_name) { ret = -EISCONN; trans = rxrpc_name_to_transport(sock, m->msg_name, m->msg_namelen, 0, GFP_KERNEL); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; goto out; } } else { trans = rx->trans; if (trans) atomic_inc(&trans->usage); } switch (rx->sk.sk_state) { case RXRPC_SERVER_LISTENING: if (!m->msg_name) { ret = rxrpc_server_sendmsg(iocb, rx, m, len); break; } case RXRPC_SERVER_BOUND: case RXRPC_CLIENT_BOUND: if (!m->msg_name) { ret = -ENOTCONN; break; } case RXRPC_CLIENT_CONNECTED: ret = rxrpc_client_sendmsg(iocb, rx, trans, m, len); break; default: ret = -ENOTCONN; break; } out: release_sock(&rx->sk); if (trans) rxrpc_put_transport(trans); _leave(" = %d", ret); return ret; } /* * set RxRPC socket options */ static int rxrpc_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen) { struct rxrpc_sock *rx = rxrpc_sk(sock->sk); unsigned min_sec_level; int ret; _enter(",%d,%d,,%d", level, optname, optlen); lock_sock(&rx->sk); ret = -EOPNOTSUPP; if (level == SOL_RXRPC) { switch (optname) { case RXRPC_EXCLUSIVE_CONNECTION: ret = -EINVAL; if (optlen != 0) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNCONNECTED) goto error; set_bit(RXRPC_SOCK_EXCLUSIVE_CONN, &rx->flags); goto success; case RXRPC_SECURITY_KEY: ret = -EINVAL; if (rx->key) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNCONNECTED) goto error; ret = rxrpc_request_key(rx, optval, optlen); goto error; case RXRPC_SECURITY_KEYRING: ret = -EINVAL; if (rx->key) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNCONNECTED) goto error; ret = rxrpc_server_keyring(rx, optval, optlen); goto error; case RXRPC_MIN_SECURITY_LEVEL: ret = -EINVAL; if (optlen != sizeof(unsigned)) goto error; ret = -EISCONN; if (rx->sk.sk_state != RXRPC_UNCONNECTED) goto error; ret = get_user(min_sec_level, (unsigned __user *) optval); if (ret < 0) goto error; ret = -EINVAL; if (min_sec_level > RXRPC_SECURITY_MAX) goto error; rx->min_sec_level = min_sec_level; goto success; default: break; } } success: ret = 0; error: release_sock(&rx->sk); return ret; } /* * permit an RxRPC socket to be polled */ static unsigned int rxrpc_poll(struct file *file, struct socket *sock, poll_table *wait) { unsigned int mask; struct sock *sk = sock->sk; poll_wait(file, sk->sk_sleep, wait); mask = 0; /* the socket is readable if there are any messages waiting on the Rx * queue */ if (!skb_queue_empty(&sk->sk_receive_queue)) mask |= POLLIN | POLLRDNORM; /* the socket is writable if there is space to add new data to the * socket; there is no guarantee that any particular call in progress * on the socket may have space in the Tx ACK window */ if (rxrpc_writable(sk)) mask |= POLLOUT | POLLWRNORM; return mask; } /* * create an RxRPC socket */ static int rxrpc_create(struct net *net, struct socket *sock, int protocol) { struct rxrpc_sock *rx; struct sock *sk; _enter("%p,%d", sock, protocol); if (net != &init_net) return -EAFNOSUPPORT; /* we support transport protocol UDP only */ if (protocol != PF_INET) return -EPROTONOSUPPORT; if (sock->type != SOCK_DGRAM) return -ESOCKTNOSUPPORT; sock->ops = &rxrpc_rpc_ops; sock->state = SS_UNCONNECTED; sk = sk_alloc(net, PF_RXRPC, GFP_KERNEL, &rxrpc_proto); if (!sk) return -ENOMEM; sock_init_data(sock, sk); sk->sk_state = RXRPC_UNCONNECTED; sk->sk_write_space = rxrpc_write_space; sk->sk_max_ack_backlog = sysctl_rxrpc_max_qlen; sk->sk_destruct = rxrpc_sock_destructor; rx = rxrpc_sk(sk); rx->proto = protocol; rx->calls = RB_ROOT; INIT_LIST_HEAD(&rx->listen_link); INIT_LIST_HEAD(&rx->secureq); INIT_LIST_HEAD(&rx->acceptq); rwlock_init(&rx->call_lock); memset(&rx->srx, 0, sizeof(rx->srx)); _leave(" = 0 [%p]", rx); return 0; } /* * RxRPC socket destructor */ static void rxrpc_sock_destructor(struct sock *sk) { _enter("%p", sk); rxrpc_purge_queue(&sk->sk_receive_queue); BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc)); BUG_TRAP(sk_unhashed(sk)); BUG_TRAP(!sk->sk_socket); if (!sock_flag(sk, SOCK_DEAD)) { printk("Attempt to release alive rxrpc socket: %p\n", sk); return; } } /* * release an RxRPC socket */ static int rxrpc_release_sock(struct sock *sk) { struct rxrpc_sock *rx = rxrpc_sk(sk); _enter("%p{%d,%d}", sk, sk->sk_state, atomic_read(&sk->sk_refcnt)); /* declare the socket closed for business */ sock_orphan(sk); sk->sk_shutdown = SHUTDOWN_MASK; spin_lock_bh(&sk->sk_receive_queue.lock); sk->sk_state = RXRPC_CLOSE; spin_unlock_bh(&sk->sk_receive_queue.lock); ASSERTCMP(rx->listen_link.next, !=, LIST_POISON1); if (!list_empty(&rx->listen_link)) { write_lock_bh(&rx->local->services_lock); list_del(&rx->listen_link); write_unlock_bh(&rx->local->services_lock); } /* try to flush out this socket */ rxrpc_release_calls_on_socket(rx); flush_workqueue(rxrpc_workqueue); rxrpc_purge_queue(&sk->sk_receive_queue); if (rx->conn) { rxrpc_put_connection(rx->conn); rx->conn = NULL; } if (rx->bundle) { rxrpc_put_bundle(rx->trans, rx->bundle); rx->bundle = NULL; } if (rx->trans) { rxrpc_put_transport(rx->trans); rx->trans = NULL; } if (rx->local) { rxrpc_put_local(rx->local); rx->local = NULL; } key_put(rx->key); rx->key = NULL; key_put(rx->securities); rx->securities = NULL; sock_put(sk); _leave(" = 0"); return 0; } /* * release an RxRPC BSD socket on close() or equivalent */ static int rxrpc_release(struct socket *sock) { struct sock *sk = sock->sk; _enter("%p{%p}", sock, sk); if (!sk) return 0; sock->sk = NULL; return rxrpc_release_sock(sk); } /* * RxRPC network protocol */ static const struct proto_ops rxrpc_rpc_ops = { .family = PF_UNIX, .owner = THIS_MODULE, .release = rxrpc_release, .bind = rxrpc_bind, .connect = rxrpc_connect, .socketpair = sock_no_socketpair, .accept = sock_no_accept, .getname = sock_no_getname, .poll = rxrpc_poll, .ioctl = sock_no_ioctl, .listen = rxrpc_listen, .shutdown = sock_no_shutdown, .setsockopt = rxrpc_setsockopt, .getsockopt = sock_no_getsockopt, .sendmsg = rxrpc_sendmsg, .recvmsg = rxrpc_recvmsg, .mmap = sock_no_mmap, .sendpage = sock_no_sendpage, }; static struct proto rxrpc_proto = { .name = "RXRPC", .owner = THIS_MODULE, .obj_size = sizeof(struct rxrpc_sock), .max_header = sizeof(struct rxrpc_header), }; static struct net_proto_family rxrpc_family_ops = { .family = PF_RXRPC, .create = rxrpc_create, .owner = THIS_MODULE, }; /* * initialise and register the RxRPC protocol */ static int __init af_rxrpc_init(void) { struct sk_buff *dummy_skb; int ret = -1; BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof(dummy_skb->cb)); rxrpc_epoch = htonl(get_seconds()); ret = -ENOMEM; rxrpc_call_jar = kmem_cache_create( "rxrpc_call_jar", sizeof(struct rxrpc_call), 0, SLAB_HWCACHE_ALIGN, NULL); if (!rxrpc_call_jar) { printk(KERN_NOTICE "RxRPC: Failed to allocate call jar\n"); goto error_call_jar; } rxrpc_workqueue = create_workqueue("krxrpcd"); if (!rxrpc_workqueue) { printk(KERN_NOTICE "RxRPC: Failed to allocate work queue\n"); goto error_work_queue; } ret = proto_register(&rxrpc_proto, 1); if (ret < 0) { printk(KERN_CRIT "RxRPC: Cannot register protocol\n"); goto error_proto; } ret = sock_register(&rxrpc_family_ops); if (ret < 0) { printk(KERN_CRIT "RxRPC: Cannot register socket family\n"); goto error_sock; } ret = register_key_type(&key_type_rxrpc); if (ret < 0) { printk(KERN_CRIT "RxRPC: Cannot register client key type\n"); goto error_key_type; } ret = register_key_type(&key_type_rxrpc_s); if (ret < 0) { printk(KERN_CRIT "RxRPC: Cannot register server key type\n"); goto error_key_type_s; } #ifdef CONFIG_PROC_FS proc_net_fops_create(&init_net, "rxrpc_calls", 0, &rxrpc_call_seq_fops); proc_net_fops_create(&init_net, "rxrpc_conns", 0, &rxrpc_connection_seq_fops); #endif return 0; error_key_type_s: unregister_key_type(&key_type_rxrpc); error_key_type: sock_unregister(PF_RXRPC); error_sock: proto_unregister(&rxrpc_proto); error_proto: destroy_workqueue(rxrpc_workqueue); error_work_queue: kmem_cache_destroy(rxrpc_call_jar); error_call_jar: return ret; } /* * unregister the RxRPC protocol */ static void __exit af_rxrpc_exit(void) { _enter(""); unregister_key_type(&key_type_rxrpc_s); unregister_key_type(&key_type_rxrpc); sock_unregister(PF_RXRPC); proto_unregister(&rxrpc_proto); rxrpc_destroy_all_calls(); rxrpc_destroy_all_connections(); rxrpc_destroy_all_transports(); rxrpc_destroy_all_peers(); rxrpc_destroy_all_locals(); ASSERTCMP(atomic_read(&rxrpc_n_skbs), ==, 0); _debug("flush scheduled work"); flush_workqueue(rxrpc_workqueue); proc_net_remove(&init_net, "rxrpc_conns"); proc_net_remove(&init_net, "rxrpc_calls"); destroy_workqueue(rxrpc_workqueue); kmem_cache_destroy(rxrpc_call_jar); _leave(""); } module_init(af_rxrpc_init); module_exit(af_rxrpc_exit);