1 files changed, 442 insertions, 0 deletions
diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c
new file mode 100644
index 000000000..09e1e7771
--- /dev/null
+++ b/fs/smb/server/connection.c
@@ -0,0 +1,442 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *   Copyright (C) 2016 Namjae Jeon <namjae.jeon@protocolfreedom.org>
+ *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
+ */
+
+#include <linux/mutex.h>
+#include <linux/freezer.h>
+#include <linux/module.h>
+
+#include "server.h"
+#include "smb_common.h"
+#include "mgmt/ksmbd_ida.h"
+#include "connection.h"
+#include "transport_tcp.h"
+#include "transport_rdma.h"
+
+static DEFINE_MUTEX(init_lock);
+
+static struct ksmbd_conn_ops default_conn_ops;
+
+LIST_HEAD(conn_list);
+DECLARE_RWSEM(conn_list_lock);
+
+/**
+ * ksmbd_conn_free() - free resources of the connection instance
+ *
+ * @conn:	connection instance to be cleand up
+ *
+ * During the thread termination, the corresponding conn instance
+ * resources(sock/memory) are released and finally the conn object is freed.
+ */
+void ksmbd_conn_free(struct ksmbd_conn *conn)
+{
+	down_write(&conn_list_lock);
+	list_del(&conn->conns_list);
+	up_write(&conn_list_lock);
+
+	xa_destroy(&conn->sessions);
+	kvfree(conn->request_buf);
+	kfree(conn->preauth_info);
+	kfree(conn);
+}
+
+/**
+ * ksmbd_conn_alloc() - initialize a new connection instance
+ *
+ * Return:	ksmbd_conn struct on success, otherwise NULL
+ */
+struct ksmbd_conn *ksmbd_conn_alloc(void)
+{
+	struct ksmbd_conn *conn;
+
+	conn = kzalloc(sizeof(struct ksmbd_conn), GFP_KERNEL);
+	if (!conn)
+		return NULL;
+
+	conn->need_neg = true;
+	ksmbd_conn_set_new(conn);
+	conn->local_nls = load_nls("utf8");
+	if (!conn->local_nls)
+		conn->local_nls = load_nls_default();
+	if (IS_ENABLED(CONFIG_UNICODE))
+		conn->um = utf8_load(UNICODE_AGE(12, 1, 0));
+	else
+		conn->um = ERR_PTR(-EOPNOTSUPP);
+	if (IS_ERR(conn->um))
+		conn->um = NULL;
+	atomic_set(&conn->req_running, 0);
+	atomic_set(&conn->r_count, 0);
+	conn->total_credits = 1;
+	conn->outstanding_credits = 0;
+
+	init_waitqueue_head(&conn->req_running_q);
+	init_waitqueue_head(&conn->r_count_q);
+	INIT_LIST_HEAD(&conn->conns_list);
+	INIT_LIST_HEAD(&conn->requests);
+	INIT_LIST_HEAD(&conn->async_requests);
+	spin_lock_init(&conn->request_lock);
+	spin_lock_init(&conn->credits_lock);
+	ida_init(&conn->async_ida);
+	xa_init(&conn->sessions);
+
+	spin_lock_init(&conn->llist_lock);
+	INIT_LIST_HEAD(&conn->lock_list);
+
+	init_rwsem(&conn->session_lock);
+
+	down_write(&conn_list_lock);
+	list_add(&conn->conns_list, &conn_list);
+	up_write(&conn_list_lock);
+	return conn;
+}
+
+bool ksmbd_conn_lookup_dialect(struct ksmbd_conn *c)
+{
+	struct ksmbd_conn *t;
+	bool ret = false;
+
+	down_read(&conn_list_lock);
+	list_for_each_entry(t, &conn_list, conns_list) {
+		if (memcmp(t->ClientGUID, c->ClientGUID, SMB2_CLIENT_GUID_SIZE))
+			continue;
+
+		ret = true;
+		break;
+	}
+	up_read(&conn_list_lock);
+	return ret;
+}
+
+void ksmbd_conn_enqueue_request(struct ksmbd_work *work)
+{
+	struct ksmbd_conn *conn = work->conn;
+	struct list_head *requests_queue = NULL;
+
+	if (conn->ops->get_cmd_val(work) != SMB2_CANCEL_HE)
+		requests_queue = &conn->requests;
+
+	if (requests_queue) {
+		atomic_inc(&conn->req_running);
+		spin_lock(&conn->request_lock);
+		list_add_tail(&work->request_entry, requests_queue);
+		spin_unlock(&conn->request_lock);
+	}
+}
+
+void ksmbd_conn_try_dequeue_request(struct ksmbd_work *work)
+{
+	struct ksmbd_conn *conn = work->conn;
+
+	if (list_empty(&work->request_entry) &&
+	    list_empty(&work->async_request_entry))
+		return;
+
+	atomic_dec(&conn->req_running);
+	spin_lock(&conn->request_lock);
+	list_del_init(&work->request_entry);
+	spin_unlock(&conn->request_lock);
+	if (work->asynchronous)
+		release_async_work(work);
+
+	wake_up_all(&conn->req_running_q);
+}
+
+void ksmbd_conn_lock(struct ksmbd_conn *conn)
+{
+	mutex_lock(&conn->srv_mutex);
+}
+
+void ksmbd_conn_unlock(struct ksmbd_conn *conn)
+{
+	mutex_unlock(&conn->srv_mutex);
+}
+
+void ksmbd_all_conn_set_status(u64 sess_id, u32 status)
+{
+	struct ksmbd_conn *conn;
+
+	down_read(&conn_list_lock);
+	list_for_each_entry(conn, &conn_list, conns_list) {
+		if (conn->binding || xa_load(&conn->sessions, sess_id))
+			WRITE_ONCE(conn->status, status);
+	}
+	up_read(&conn_list_lock);
+}
+
+void ksmbd_conn_wait_idle(struct ksmbd_conn *conn, u64 sess_id)
+{
+	wait_event(conn->req_running_q, atomic_read(&conn->req_running) < 2);
+}
+
+int ksmbd_conn_write(struct ksmbd_work *work)
+{
+	struct ksmbd_conn *conn = work->conn;
+	int sent;
+
+	if (!work->response_buf) {
+		pr_err("NULL response header\n");
+		return -EINVAL;
+	}
+
+	if (work->send_no_response)
+		return 0;
+
+	if (!work->iov_idx)
+		return -EINVAL;
+
+	ksmbd_conn_lock(conn);
+	sent = conn->transport->ops->writev(conn->transport, work->iov,
+			work->iov_cnt,
+			get_rfc1002_len(work->iov[0].iov_base) + 4,
+			work->need_invalidate_rkey,
+			work->remote_key);
+	ksmbd_conn_unlock(conn);
+
+	if (sent < 0) {
+		pr_err("Failed to send message: %d\n", sent);
+		return sent;
+	}
+
+	return 0;
+}
+
+int ksmbd_conn_rdma_read(struct ksmbd_conn *conn,
+			 void *buf, unsigned int buflen,
+			 struct smb2_buffer_desc_v1 *desc,
+			 unsigned int desc_len)
+{
+	int ret = -EINVAL;
+
+	if (conn->transport->ops->rdma_read)
+		ret = conn->transport->ops->rdma_read(conn->transport,
+						      buf, buflen,
+						      desc, desc_len);
+	return ret;
+}
+
+int ksmbd_conn_rdma_write(struct ksmbd_conn *conn,
+			  void *buf, unsigned int buflen,
+			  struct smb2_buffer_desc_v1 *desc,
+			  unsigned int desc_len)
+{
+	int ret = -EINVAL;
+
+	if (conn->transport->ops->rdma_write)
+		ret = conn->transport->ops->rdma_write(conn->transport,
+						       buf, buflen,
+						       desc, desc_len);
+	return ret;
+}
+
+bool ksmbd_conn_alive(struct ksmbd_conn *conn)
+{
+	if (!ksmbd_server_running())
+		return false;
+
+	if (ksmbd_conn_exiting(conn))
+		return false;
+
+	if (kthread_should_stop())
+		return false;
+
+	if (atomic_read(&conn->stats.open_files_count) > 0)
+		return true;
+
+	/*
+	 * Stop current session if the time that get last request from client
+	 * is bigger than deadtime user configured and opening file count is
+	 * zero.
+	 */
+	if (server_conf.deadtime > 0 &&
+	    time_after(jiffies, conn->last_active + server_conf.deadtime)) {
+		ksmbd_debug(CONN, "No response from client in %lu minutes\n",
+			    server_conf.deadtime / SMB_ECHO_INTERVAL);
+		return false;
+	}
+	return true;
+}
+
+#define SMB1_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb_hdr))
+#define SMB2_MIN_SUPPORTED_HEADER_SIZE (sizeof(struct smb2_hdr) + 4)
+
+/**
+ * ksmbd_conn_handler_loop() - session thread to listen on new smb requests
+ * @p:		connection instance
+ *
+ * One thread each per connection
+ *
+ * Return:	0 on success
+ */
+int ksmbd_conn_handler_loop(void *p)
+{
+	struct ksmbd_conn *conn = (struct ksmbd_conn *)p;
+	struct ksmbd_transport *t = conn->transport;
+	unsigned int pdu_size, max_allowed_pdu_size;
+	char hdr_buf[4] = {0,};
+	int size;
+
+	mutex_init(&conn->srv_mutex);
+	__module_get(THIS_MODULE);
+
+	if (t->ops->prepare && t->ops->prepare(t))
+		goto out;
+
+	conn->last_active = jiffies;
+	set_freezable();
+	while (ksmbd_conn_alive(conn)) {
+		if (try_to_freeze())
+			continue;
+
+		kvfree(conn->request_buf);
+		conn->request_buf = NULL;
+
+		size = t->ops->read(t, hdr_buf, sizeof(hdr_buf), -1);
+		if (size != sizeof(hdr_buf))
+			break;
+
+		pdu_size = get_rfc1002_len(hdr_buf);
+		ksmbd_debug(CONN, "RFC1002 header %u bytes\n", pdu_size);
+
+		if (ksmbd_conn_good(conn))
+			max_allowed_pdu_size =
+				SMB3_MAX_MSGSIZE + conn->vals->max_write_size;
+		else
+			max_allowed_pdu_size = SMB3_MAX_MSGSIZE;
+
+		if (pdu_size > max_allowed_pdu_size) {
+			pr_err_ratelimited("PDU length(%u) exceeded maximum allowed pdu size(%u) on connection(%d)\n",
+					pdu_size, max_allowed_pdu_size,
+					READ_ONCE(conn->status));
+			break;
+		}
+
+		/*
+		 * Check maximum pdu size(0x00FFFFFF).
+		 */
+		if (pdu_size > MAX_STREAM_PROT_LEN)
+			break;
+
+		if (pdu_size < SMB1_MIN_SUPPORTED_HEADER_SIZE)
+			break;
+
+		/* 4 for rfc1002 length field */
+		/* 1 for implied bcc[0] */
+		size = pdu_size + 4 + 1;
+		conn->request_buf = kvmalloc(size, GFP_KERNEL);
+		if (!conn->request_buf)
+			break;
+
+		memcpy(conn->request_buf, hdr_buf, sizeof(hdr_buf));
+
+		/*
+		 * We already read 4 bytes to find out PDU size, now
+		 * read in PDU
+		 */
+		size = t->ops->read(t, conn->request_buf + 4, pdu_size, 2);
+		if (size < 0) {
+			pr_err("sock_read failed: %d\n", size);
+			break;
+		}
+
+		if (size != pdu_size) {
+			pr_err("PDU error. Read: %d, Expected: %d\n",
+			       size, pdu_size);
+			continue;
+		}
+
+		if (!ksmbd_smb_request(conn))
+			break;
+
+		if (((struct smb2_hdr *)smb2_get_msg(conn->request_buf))->ProtocolId ==
+		    SMB2_PROTO_NUMBER) {
+			if (pdu_size < SMB2_MIN_SUPPORTED_HEADER_SIZE)
+				break;
+		}
+
+		if (!default_conn_ops.process_fn) {
+			pr_err("No connection request callback\n");
+			break;
+		}
+
+		if (default_conn_ops.process_fn(conn)) {
+			pr_err("Cannot handle request\n");
+			break;
+		}
+	}
+
+out:
+	ksmbd_conn_set_releasing(conn);
+	/* Wait till all reference dropped to the Server object*/
+	wait_event(conn->r_count_q, atomic_read(&conn->r_count) == 0);
+
+	if (IS_ENABLED(CONFIG_UNICODE))
+		utf8_unload(conn->um);
+	unload_nls(conn->local_nls);
+	if (default_conn_ops.terminate_fn)
+		default_conn_ops.terminate_fn(conn);
+	t->ops->disconnect(t);
+	module_put(THIS_MODULE);
+	return 0;
+}
+
+void ksmbd_conn_init_server_callbacks(struct ksmbd_conn_ops *ops)
+{
+	default_conn_ops.process_fn = ops->process_fn;
+	default_conn_ops.terminate_fn = ops->terminate_fn;
+}
+
+int ksmbd_conn_transport_init(void)
+{
+	int ret;
+
+	mutex_lock(&init_lock);
+	ret = ksmbd_tcp_init();
+	if (ret) {
+		pr_err("Failed to init TCP subsystem: %d\n", ret);
+		goto out;
+	}
+
+	ret = ksmbd_rdma_init();
+	if (ret) {
+		pr_err("Failed to init RDMA subsystem: %d\n", ret);
+		goto out;
+	}
+out:
+	mutex_unlock(&init_lock);
+	return ret;
+}
+
+static void stop_sessions(void)
+{
+	struct ksmbd_conn *conn;
+	struct ksmbd_transport *t;
+
+again:
+	down_read(&conn_list_lock);
+	list_for_each_entry(conn, &conn_list, conns_list) {
+		t = conn->transport;
+		ksmbd_conn_set_exiting(conn);
+		if (t->ops->shutdown) {
+			up_read(&conn_list_lock);
+			t->ops->shutdown(t);
+			down_read(&conn_list_lock);
+		}
+	}
+	up_read(&conn_list_lock);
+
+	if (!list_empty(&conn_list)) {
+		schedule_timeout_interruptible(HZ / 10); /* 100ms */
+		goto again;
+	}
+}
+
+void ksmbd_conn_transport_destroy(void)
+{
+	mutex_lock(&init_lock);
+	ksmbd_tcp_destroy();
+	ksmbd_rdma_destroy();
+	stop_sessions();
+	mutex_unlock(&init_lock);
+}