1 files changed, 1077 insertions, 0 deletions

diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
new file mode 100644
index 000000000..0354f90dc
--- /dev/null
+++ b/net/rxrpc/af_rxrpc.c
@@ -0,0 +1,1077 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* AF_RXRPC implementation
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/slab.h>
+#include <linux/skbuff.h>
+#include <linux/random.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>
+#define CREATE_TRACE_POINTS
+#include "ar-internal.h"
+
+MODULE_DESCRIPTION("RxRPC network protocol");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_RXRPC);
+
+unsigned int rxrpc_debug; // = RXRPC_DEBUG_KPROTO;
+module_param_named(debug, rxrpc_debug, uint, 0644);
+MODULE_PARM_DESC(debug, "RxRPC debugging mask");
+
+static struct proto rxrpc_proto;
+static const struct proto_ops rxrpc_rpc_ops;
+
+/* current debugging ID */
+atomic_t rxrpc_debug_id;
+EXPORT_SYMBOL(rxrpc_debug_id);
+
+/* count of skbs currently in use */
+atomic_t rxrpc_n_tx_skbs, rxrpc_n_rx_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 refcount_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);
+	rcu_read_lock();
+	if (rxrpc_writable(sk)) {
+		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
+
+		if (skwq_has_sleeper(wq))
+			wake_up_interruptible(&wq->wait);
+		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
+	}
+	rcu_read_unlock();
+}
+
+/*
+ * validate an RxRPC address
+ */
+static int rxrpc_validate_address(struct rxrpc_sock *rx,
+				  struct sockaddr_rxrpc *srx,
+				  int len)
+{
+	unsigned int tail;
+
+	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->family &&
+	    srx->transport.family == AF_INET && rx->family != AF_INET6)
+		return -EAFNOSUPPORT;
+
+	switch (srx->transport.family) {
+	case AF_INET:
+		if (srx->transport_len < sizeof(struct sockaddr_in))
+			return -EINVAL;
+		tail = offsetof(struct sockaddr_rxrpc, transport.sin.__pad);
+		break;
+
+#ifdef CONFIG_AF_RXRPC_IPV6
+	case AF_INET6:
+		if (srx->transport_len < sizeof(struct sockaddr_in6))
+			return -EINVAL;
+		tail = offsetof(struct sockaddr_rxrpc, transport) +
+			sizeof(struct sockaddr_in6);
+		break;
+#endif
+
+	default:
+		return -EAFNOSUPPORT;
+	}
+
+	if (tail < len)
+		memset((void *)srx + tail, 0, len - tail);
+	_debug("INET: %pISp", &srx->transport);
+	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 rxrpc_local *local;
+	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
+	u16 service_id;
+	int ret;
+
+	_enter("%p,%p,%d", rx, saddr, len);
+
+	ret = rxrpc_validate_address(rx, srx, len);
+	if (ret < 0)
+		goto error;
+	service_id = srx->srx_service;
+
+	lock_sock(&rx->sk);
+
+	switch (rx->sk.sk_state) {
+	case RXRPC_UNBOUND:
+		rx->srx = *srx;
+		local = rxrpc_lookup_local(sock_net(&rx->sk), &rx->srx);
+		if (IS_ERR(local)) {
+			ret = PTR_ERR(local);
+			goto error_unlock;
+		}
+
+		if (service_id) {
+			write_lock(&local->services_lock);
+			if (rcu_access_pointer(local->service))
+				goto service_in_use;
+			rx->local = local;
+			rcu_assign_pointer(local->service, rx);
+			write_unlock(&local->services_lock);
+
+			rx->sk.sk_state = RXRPC_SERVER_BOUND;
+		} else {
+			rx->local = local;
+			rx->sk.sk_state = RXRPC_CLIENT_BOUND;
+		}
+		break;
+
+	case RXRPC_SERVER_BOUND:
+		ret = -EINVAL;
+		if (service_id == 0)
+			goto error_unlock;
+		ret = -EADDRINUSE;
+		if (service_id == rx->srx.srx_service)
+			goto error_unlock;
+		ret = -EINVAL;
+		srx->srx_service = rx->srx.srx_service;
+		if (memcmp(srx, &rx->srx, sizeof(*srx)) != 0)
+			goto error_unlock;
+		rx->second_service = service_id;
+		rx->sk.sk_state = RXRPC_SERVER_BOUND2;
+		break;
+
+	default:
+		ret = -EINVAL;
+		goto error_unlock;
+	}
+
+	release_sock(&rx->sk);
+	_leave(" = 0");
+	return 0;
+
+service_in_use:
+	write_unlock(&local->services_lock);
+	rxrpc_unuse_local(local);
+	rxrpc_put_local(local);
+	ret = -EADDRINUSE;
+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);
+	unsigned int max, old;
+	int ret;
+
+	_enter("%p,%d", rx, backlog);
+
+	lock_sock(&rx->sk);
+
+	switch (rx->sk.sk_state) {
+	case RXRPC_UNBOUND:
+		ret = -EADDRNOTAVAIL;
+		break;
+	case RXRPC_SERVER_BOUND:
+	case RXRPC_SERVER_BOUND2:
+		ASSERT(rx->local != NULL);
+		max = READ_ONCE(rxrpc_max_backlog);
+		ret = -EINVAL;
+		if (backlog == INT_MAX)
+			backlog = max;
+		else if (backlog < 0 || backlog > max)
+			break;
+		old = sk->sk_max_ack_backlog;
+		sk->sk_max_ack_backlog = backlog;
+		ret = rxrpc_service_prealloc(rx, GFP_KERNEL);
+		if (ret == 0)
+			rx->sk.sk_state = RXRPC_SERVER_LISTENING;
+		else
+			sk->sk_max_ack_backlog = old;
+		break;
+	case RXRPC_SERVER_LISTENING:
+		if (backlog == 0) {
+			rx->sk.sk_state = RXRPC_SERVER_LISTEN_DISABLED;
+			sk->sk_max_ack_backlog = 0;
+			rxrpc_discard_prealloc(rx);
+			ret = 0;
+			break;
+		}
+		fallthrough;
+	default:
+		ret = -EBUSY;
+		break;
+	}
+
+	release_sock(&rx->sk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/**
+ * 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
+ * @key: The security context to use (defaults to socket setting)
+ * @user_call_ID: The ID to use
+ * @tx_total_len: Total length of data to transmit during the call (or -1)
+ * @gfp: The allocation constraints
+ * @notify_rx: Where to send notifications instead of socket queue
+ * @upgrade: Request service upgrade for call
+ * @interruptibility: The call is interruptible, or can be canceled.
+ * @debug_id: The debug ID for tracing to be assigned to the call
+ *
+ * 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,
+					   s64 tx_total_len,
+					   gfp_t gfp,
+					   rxrpc_notify_rx_t notify_rx,
+					   bool upgrade,
+					   enum rxrpc_interruptibility interruptibility,
+					   unsigned int debug_id)
+{
+	struct rxrpc_conn_parameters cp;
+	struct rxrpc_call_params p;
+	struct rxrpc_call *call;
+	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
+	int ret;
+
+	_enter(",,%x,%lx", key_serial(key), user_call_ID);
+
+	ret = rxrpc_validate_address(rx, srx, sizeof(*srx));
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	lock_sock(&rx->sk);
+
+	if (!key)
+		key = rx->key;
+	if (key && !key->payload.data[0])
+		key = NULL; /* a no-security key */
+
+	memset(&p, 0, sizeof(p));
+	p.user_call_ID		= user_call_ID;
+	p.tx_total_len		= tx_total_len;
+	p.interruptibility	= interruptibility;
+	p.kernel		= true;
+
+	memset(&cp, 0, sizeof(cp));
+	cp.local		= rx->local;
+	cp.key			= key;
+	cp.security_level	= rx->min_sec_level;
+	cp.exclusive		= false;
+	cp.upgrade		= upgrade;
+	cp.service_id		= srx->srx_service;
+	call = rxrpc_new_client_call(rx, &cp, srx, &p, gfp, debug_id);
+	/* The socket has been unlocked. */
+	if (!IS_ERR(call)) {
+		call->notify_rx = notify_rx;
+		mutex_unlock(&call->user_mutex);
+	}
+
+	rxrpc_put_peer(cp.peer);
+	_leave(" = %p", call);
+	return call;
+}
+EXPORT_SYMBOL(rxrpc_kernel_begin_call);
+
+/*
+ * Dummy function used to stop the notifier talking to recvmsg().
+ */
+static void rxrpc_dummy_notify_rx(struct sock *sk, struct rxrpc_call *rxcall,
+				  unsigned long call_user_ID)
+{
+}
+
+/**
+ * rxrpc_kernel_end_call - Allow a kernel service to end a call it was using
+ * @sock: The socket the call is on
+ * @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 socket *sock, struct rxrpc_call *call)
+{
+	_enter("%d{%d}", call->debug_id, refcount_read(&call->ref));
+
+	mutex_lock(&call->user_mutex);
+	rxrpc_release_call(rxrpc_sk(sock->sk), call);
+
+	/* Make sure we're not going to call back into a kernel service */
+	if (call->notify_rx) {
+		spin_lock_bh(&call->notify_lock);
+		call->notify_rx = rxrpc_dummy_notify_rx;
+		spin_unlock_bh(&call->notify_lock);
+	}
+
+	mutex_unlock(&call->user_mutex);
+	rxrpc_put_call(call, rxrpc_call_put_kernel);
+}
+EXPORT_SYMBOL(rxrpc_kernel_end_call);
+
+/**
+ * rxrpc_kernel_check_life - Check to see whether a call is still alive
+ * @sock: The socket the call is on
+ * @call: The call to check
+ *
+ * Allow a kernel service to find out whether a call is still alive -
+ * ie. whether it has completed.
+ */
+bool rxrpc_kernel_check_life(const struct socket *sock,
+			     const struct rxrpc_call *call)
+{
+	return call->state != RXRPC_CALL_COMPLETE;
+}
+EXPORT_SYMBOL(rxrpc_kernel_check_life);
+
+/**
+ * rxrpc_kernel_get_epoch - Retrieve the epoch value from a call.
+ * @sock: The socket the call is on
+ * @call: The call to query
+ *
+ * Allow a kernel service to retrieve the epoch value from a service call to
+ * see if the client at the other end rebooted.
+ */
+u32 rxrpc_kernel_get_epoch(struct socket *sock, struct rxrpc_call *call)
+{
+	return call->conn->proto.epoch;
+}
+EXPORT_SYMBOL(rxrpc_kernel_get_epoch);
+
+/**
+ * rxrpc_kernel_new_call_notification - Get notifications of new calls
+ * @sock: The socket to intercept received messages on
+ * @notify_new_call: Function to be called when new calls appear
+ * @discard_new_call: Function to discard preallocated calls
+ *
+ * Allow a kernel service to be given notifications about new calls.
+ */
+void rxrpc_kernel_new_call_notification(
+	struct socket *sock,
+	rxrpc_notify_new_call_t notify_new_call,
+	rxrpc_discard_new_call_t discard_new_call)
+{
+	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
+
+	rx->notify_new_call = notify_new_call;
+	rx->discard_new_call = discard_new_call;
+}
+EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
+
+/**
+ * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
+ * @sock: The socket the call is on
+ * @call: The call to configure
+ * @hard_timeout: The maximum lifespan of the call in jiffies
+ *
+ * Set the maximum lifespan of a call.  The call will end with ETIME or
+ * ETIMEDOUT if it takes longer than this.
+ */
+void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
+			       unsigned long hard_timeout)
+{
+	unsigned long now;
+
+	mutex_lock(&call->user_mutex);
+
+	now = jiffies;
+	hard_timeout += now;
+	WRITE_ONCE(call->expect_term_by, hard_timeout);
+	rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
+
+	mutex_unlock(&call->user_mutex);
+}
+EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
+
+/*
+ * 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 rxrpc_sock *rx = rxrpc_sk(sock->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);
+
+	ret = -EISCONN;
+	if (test_bit(RXRPC_SOCK_CONNECTED, &rx->flags))
+		goto error;
+
+	switch (rx->sk.sk_state) {
+	case RXRPC_UNBOUND:
+		rx->sk.sk_state = RXRPC_CLIENT_UNBOUND;
+	case RXRPC_CLIENT_UNBOUND:
+	case RXRPC_CLIENT_BOUND:
+		break;
+	default:
+		ret = -EBUSY;
+		goto error;
+	}
+
+	rx->connect_srx = *srx;
+	set_bit(RXRPC_SOCK_CONNECTED, &rx->flags);
+	ret = 0;
+
+error:
+	release_sock(&rx->sk);
+	return ret;
+}
+
+/*
+ * 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 socket *sock, struct msghdr *m, size_t len)
+{
+	struct rxrpc_local *local;
+	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;
+		}
+	}
+
+	lock_sock(&rx->sk);
+
+	switch (rx->sk.sk_state) {
+	case RXRPC_UNBOUND:
+	case RXRPC_CLIENT_UNBOUND:
+		rx->srx.srx_family = AF_RXRPC;
+		rx->srx.srx_service = 0;
+		rx->srx.transport_type = SOCK_DGRAM;
+		rx->srx.transport.family = rx->family;
+		switch (rx->family) {
+		case AF_INET:
+			rx->srx.transport_len = sizeof(struct sockaddr_in);
+			break;
+#ifdef CONFIG_AF_RXRPC_IPV6
+		case AF_INET6:
+			rx->srx.transport_len = sizeof(struct sockaddr_in6);
+			break;
+#endif
+		default:
+			ret = -EAFNOSUPPORT;
+			goto error_unlock;
+		}
+		local = rxrpc_lookup_local(sock_net(sock->sk), &rx->srx);
+		if (IS_ERR(local)) {
+			ret = PTR_ERR(local);
+			goto error_unlock;
+		}
+
+		rx->local = local;
+		rx->sk.sk_state = RXRPC_CLIENT_BOUND;
+		fallthrough;
+
+	case RXRPC_CLIENT_BOUND:
+		if (!m->msg_name &&
+		    test_bit(RXRPC_SOCK_CONNECTED, &rx->flags)) {
+			m->msg_name = &rx->connect_srx;
+			m->msg_namelen = sizeof(rx->connect_srx);
+		}
+		fallthrough;
+	case RXRPC_SERVER_BOUND:
+	case RXRPC_SERVER_LISTENING:
+		ret = rxrpc_do_sendmsg(rx, m, len);
+		/* The socket has been unlocked */
+		goto out;
+	default:
+		ret = -EINVAL;
+		goto error_unlock;
+	}
+
+error_unlock:
+	release_sock(&rx->sk);
+out:
+	_leave(" = %d", ret);
+	return ret;
+}
+
+int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val)
+{
+	if (sk->sk_state != RXRPC_UNBOUND)
+		return -EISCONN;
+	if (val > RXRPC_SECURITY_MAX)
+		return -EINVAL;
+	lock_sock(sk);
+	rxrpc_sk(sk)->min_sec_level = val;
+	release_sock(sk);
+	return 0;
+}
+EXPORT_SYMBOL(rxrpc_sock_set_min_security_level);
+
+/*
+ * set RxRPC socket options
+ */
+static int rxrpc_setsockopt(struct socket *sock, int level, int optname,
+			    sockptr_t optval, unsigned int optlen)
+{
+	struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
+	unsigned int min_sec_level;
+	u16 service_upgrade[2];
+	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_UNBOUND)
+				goto error;
+			rx->exclusive = true;
+			goto success;
+
+		case RXRPC_SECURITY_KEY:
+			ret = -EINVAL;
+			if (rx->key)
+				goto error;
+			ret = -EISCONN;
+			if (rx->sk.sk_state != RXRPC_UNBOUND)
+				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_UNBOUND)
+				goto error;
+			ret = rxrpc_server_keyring(rx, optval, optlen);
+			goto error;
+
+		case RXRPC_MIN_SECURITY_LEVEL:
+			ret = -EINVAL;
+			if (optlen != sizeof(unsigned int))
+				goto error;
+			ret = -EISCONN;
+			if (rx->sk.sk_state != RXRPC_UNBOUND)
+				goto error;
+			ret = copy_from_sockptr(&min_sec_level, optval,
+				       sizeof(unsigned int));
+			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;
+
+		case RXRPC_UPGRADEABLE_SERVICE:
+			ret = -EINVAL;
+			if (optlen != sizeof(service_upgrade) ||
+			    rx->service_upgrade.from != 0)
+				goto error;
+			ret = -EISCONN;
+			if (rx->sk.sk_state != RXRPC_SERVER_BOUND2)
+				goto error;
+			ret = -EFAULT;
+			if (copy_from_sockptr(service_upgrade, optval,
+					   sizeof(service_upgrade)) != 0)
+				goto error;
+			ret = -EINVAL;
+			if ((service_upgrade[0] != rx->srx.srx_service ||
+			     service_upgrade[1] != rx->second_service) &&
+			    (service_upgrade[0] != rx->second_service ||
+			     service_upgrade[1] != rx->srx.srx_service))
+				goto error;
+			rx->service_upgrade.from = service_upgrade[0];
+			rx->service_upgrade.to = service_upgrade[1];
+			goto success;
+
+		default:
+			break;
+		}
+	}
+
+success:
+	ret = 0;
+error:
+	release_sock(&rx->sk);
+	return ret;
+}
+
+/*
+ * Get socket options.
+ */
+static int rxrpc_getsockopt(struct socket *sock, int level, int optname,
+			    char __user *optval, int __user *_optlen)
+{
+	int optlen;
+
+	if (level != SOL_RXRPC)
+		return -EOPNOTSUPP;
+
+	if (get_user(optlen, _optlen))
+		return -EFAULT;
+
+	switch (optname) {
+	case RXRPC_SUPPORTED_CMSG:
+		if (optlen < sizeof(int))
+			return -ETOOSMALL;
+		if (put_user(RXRPC__SUPPORTED - 1, (int __user *)optval) ||
+		    put_user(sizeof(int), _optlen))
+			return -EFAULT;
+		return 0;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/*
+ * permit an RxRPC socket to be polled
+ */
+static __poll_t rxrpc_poll(struct file *file, struct socket *sock,
+			       poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct rxrpc_sock *rx = rxrpc_sk(sk);
+	__poll_t mask;
+
+	sock_poll_wait(file, sock, wait);
+	mask = 0;
+
+	/* the socket is readable if there are any messages waiting on the Rx
+	 * queue */
+	if (!list_empty(&rx->recvmsg_q))
+		mask |= EPOLLIN | EPOLLRDNORM;
+
+	/* 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 |= EPOLLOUT | EPOLLWRNORM;
+
+	return mask;
+}
+
+/*
+ * create an RxRPC socket
+ */
+static int rxrpc_create(struct net *net, struct socket *sock, int protocol,
+			int kern)
+{
+	struct rxrpc_net *rxnet;
+	struct rxrpc_sock *rx;
+	struct sock *sk;
+
+	_enter("%p,%d", sock, protocol);
+
+	/* we support transport protocol UDP/UDP6 only */
+	if (protocol != PF_INET &&
+	    IS_ENABLED(CONFIG_AF_RXRPC_IPV6) && protocol != PF_INET6)
+		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, kern);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_init_data(sock, sk);
+	sock_set_flag(sk, SOCK_RCU_FREE);
+	sk->sk_state		= RXRPC_UNBOUND;
+	sk->sk_write_space	= rxrpc_write_space;
+	sk->sk_max_ack_backlog	= 0;
+	sk->sk_destruct		= rxrpc_sock_destructor;
+
+	rx = rxrpc_sk(sk);
+	rx->family = protocol;
+	rx->calls = RB_ROOT;
+
+	spin_lock_init(&rx->incoming_lock);
+	INIT_LIST_HEAD(&rx->sock_calls);
+	INIT_LIST_HEAD(&rx->to_be_accepted);
+	INIT_LIST_HEAD(&rx->recvmsg_q);
+	rwlock_init(&rx->recvmsg_lock);
+	rwlock_init(&rx->call_lock);
+	memset(&rx->srx, 0, sizeof(rx->srx));
+
+	rxnet = rxrpc_net(sock_net(&rx->sk));
+	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + 1);
+
+	_leave(" = 0 [%p]", rx);
+	return 0;
+}
+
+/*
+ * Kill all the calls on a socket and shut it down.
+ */
+static int rxrpc_shutdown(struct socket *sock, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct rxrpc_sock *rx = rxrpc_sk(sk);
+	int ret = 0;
+
+	_enter("%p,%d", sk, flags);
+
+	if (flags != SHUT_RDWR)
+		return -EOPNOTSUPP;
+	if (sk->sk_state == RXRPC_CLOSE)
+		return -ESHUTDOWN;
+
+	lock_sock(sk);
+
+	spin_lock_bh(&sk->sk_receive_queue.lock);
+	if (sk->sk_state < RXRPC_CLOSE) {
+		sk->sk_state = RXRPC_CLOSE;
+		sk->sk_shutdown = SHUTDOWN_MASK;
+	} else {
+		ret = -ESHUTDOWN;
+	}
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+
+	rxrpc_discard_prealloc(rx);
+
+	release_sock(sk);
+	return ret;
+}
+
+/*
+ * RxRPC socket destructor
+ */
+static void rxrpc_sock_destructor(struct sock *sk)
+{
+	_enter("%p", sk);
+
+	rxrpc_purge_queue(&sk->sk_receive_queue);
+
+	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
+	WARN_ON(!sk_unhashed(sk));
+	WARN_ON(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, refcount_read(&sk->sk_refcnt));
+
+	/* declare the socket closed for business */
+	sock_orphan(sk);
+	sk->sk_shutdown = SHUTDOWN_MASK;
+
+	/* We want to kill off all connections from a service socket
+	 * as fast as possible because we can't share these; client
+	 * sockets, on the other hand, can share an endpoint.
+	 */
+	switch (sk->sk_state) {
+	case RXRPC_SERVER_BOUND:
+	case RXRPC_SERVER_BOUND2:
+	case RXRPC_SERVER_LISTENING:
+	case RXRPC_SERVER_LISTEN_DISABLED:
+		rx->local->service_closed = true;
+		break;
+	}
+
+	spin_lock_bh(&sk->sk_receive_queue.lock);
+	sk->sk_state = RXRPC_CLOSE;
+	spin_unlock_bh(&sk->sk_receive_queue.lock);
+
+	if (rx->local && rcu_access_pointer(rx->local->service) == rx) {
+		write_lock(&rx->local->services_lock);
+		rcu_assign_pointer(rx->local->service, NULL);
+		write_unlock(&rx->local->services_lock);
+	}
+
+	/* try to flush out this socket */
+	rxrpc_discard_prealloc(rx);
+	rxrpc_release_calls_on_socket(rx);
+	flush_workqueue(rxrpc_workqueue);
+	rxrpc_purge_queue(&sk->sk_receive_queue);
+
+	rxrpc_unuse_local(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_RXRPC,
+	.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	= rxrpc_shutdown,
+	.setsockopt	= rxrpc_setsockopt,
+	.getsockopt	= rxrpc_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_wire_header),
+};
+
+static const 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)
+{
+	int ret = -1;
+	unsigned int tmp;
+
+	BUILD_BUG_ON(sizeof(struct rxrpc_skb_priv) > sizeof_field(struct sk_buff, cb));
+
+	get_random_bytes(&tmp, sizeof(tmp));
+	tmp &= 0x3fffffff;
+	if (tmp == 0)
+		tmp = 1;
+	idr_set_cursor(&rxrpc_client_conn_ids, tmp);
+
+	ret = -ENOMEM;
+	rxrpc_call_jar = kmem_cache_create(
+		"rxrpc_call_jar", sizeof(struct rxrpc_call), 0,
+		SLAB_HWCACHE_ALIGN, NULL);
+	if (!rxrpc_call_jar) {
+		pr_notice("Failed to allocate call jar\n");
+		goto error_call_jar;
+	}
+
+	rxrpc_workqueue = alloc_workqueue("krxrpcd", 0, 1);
+	if (!rxrpc_workqueue) {
+		pr_notice("Failed to allocate work queue\n");
+		goto error_work_queue;
+	}
+
+	ret = rxrpc_init_security();
+	if (ret < 0) {
+		pr_crit("Cannot initialise security\n");
+		goto error_security;
+	}
+
+	ret = register_pernet_device(&rxrpc_net_ops);
+	if (ret)
+		goto error_pernet;
+
+	ret = proto_register(&rxrpc_proto, 1);
+	if (ret < 0) {
+		pr_crit("Cannot register protocol\n");
+		goto error_proto;
+	}
+
+	ret = sock_register(&rxrpc_family_ops);
+	if (ret < 0) {
+		pr_crit("Cannot register socket family\n");
+		goto error_sock;
+	}
+
+	ret = register_key_type(&key_type_rxrpc);
+	if (ret < 0) {
+		pr_crit("Cannot register client key type\n");
+		goto error_key_type;
+	}
+
+	ret = register_key_type(&key_type_rxrpc_s);
+	if (ret < 0) {
+		pr_crit("Cannot register server key type\n");
+		goto error_key_type_s;
+	}
+
+	ret = rxrpc_sysctl_init();
+	if (ret < 0) {
+		pr_crit("Cannot register sysctls\n");
+		goto error_sysctls;
+	}
+
+	return 0;
+
+error_sysctls:
+	unregister_key_type(&key_type_rxrpc_s);
+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:
+	unregister_pernet_device(&rxrpc_net_ops);
+error_pernet:
+	rxrpc_exit_security();
+error_security:
+	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("");
+	rxrpc_sysctl_exit();
+	unregister_key_type(&key_type_rxrpc_s);
+	unregister_key_type(&key_type_rxrpc);
+	sock_unregister(PF_RXRPC);
+	proto_unregister(&rxrpc_proto);
+	unregister_pernet_device(&rxrpc_net_ops);
+	ASSERTCMP(atomic_read(&rxrpc_n_tx_skbs), ==, 0);
+	ASSERTCMP(atomic_read(&rxrpc_n_rx_skbs), ==, 0);
+
+	/* Make sure the local and peer records pinned by any dying connections
+	 * are released.
+	 */
+	rcu_barrier();
+	rxrpc_destroy_client_conn_ids();
+
+	destroy_workqueue(rxrpc_workqueue);
+	rxrpc_exit_security();
+	kmem_cache_destroy(rxrpc_call_jar);
+	_leave("");
+}
+
+module_init(af_rxrpc_init);
+module_exit(af_rxrpc_exit);