diff options
Diffstat (limited to 'fs/smb/server/connection.c')
| -rw-r--r-- | fs/smb/server/connection.c | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c new file mode 100644 index 000000000000..2a717d158f02 --- /dev/null +++ b/fs/smb/server/connection.c @@ -0,0 +1,483 @@ +// 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); + + 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); + } +} + +int ksmbd_conn_try_dequeue_request(struct ksmbd_work *work) +{ + struct ksmbd_conn *conn = work->conn; + int ret = 1; + + if (list_empty(&work->request_entry) && + list_empty(&work->async_request_entry)) + return 0; + + if (!work->multiRsp) + atomic_dec(&conn->req_running); + if (!work->multiRsp) { + spin_lock(&conn->request_lock); + list_del_init(&work->request_entry); + spin_unlock(&conn->request_lock); + if (work->asynchronous) + release_async_work(work); + ret = 0; + } + + wake_up_all(&conn->req_running_q); + return ret; +} + +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) +{ + struct ksmbd_conn *bind_conn; + + wait_event(conn->req_running_q, atomic_read(&conn->req_running) < 2); + + down_read(&conn_list_lock); + list_for_each_entry(bind_conn, &conn_list, conns_list) { + if (bind_conn == conn) + continue; + + if ((bind_conn->binding || xa_load(&bind_conn->sessions, sess_id)) && + !ksmbd_conn_releasing(bind_conn) && + atomic_read(&bind_conn->req_running)) { + wait_event(bind_conn->req_running_q, + atomic_read(&bind_conn->req_running) == 0); + } + } + up_read(&conn_list_lock); +} + +int ksmbd_conn_write(struct ksmbd_work *work) +{ + struct ksmbd_conn *conn = work->conn; + size_t len = 0; + int sent; + struct kvec iov[3]; + int iov_idx = 0; + + if (!work->response_buf) { + pr_err("NULL response header\n"); + return -EINVAL; + } + + if (work->tr_buf) { + iov[iov_idx] = (struct kvec) { work->tr_buf, + sizeof(struct smb2_transform_hdr) + 4 }; + len += iov[iov_idx++].iov_len; + } + + if (work->aux_payload_sz) { + iov[iov_idx] = (struct kvec) { work->response_buf, work->resp_hdr_sz }; + len += iov[iov_idx++].iov_len; + iov[iov_idx] = (struct kvec) { work->aux_payload_buf, work->aux_payload_sz }; + len += iov[iov_idx++].iov_len; + } else { + if (work->tr_buf) + iov[iov_idx].iov_len = work->resp_hdr_sz; + else + iov[iov_idx].iov_len = get_rfc1002_len(work->response_buf) + 4; + iov[iov_idx].iov_base = work->response_buf; + len += iov[iov_idx++].iov_len; + } + + ksmbd_conn_lock(conn); + sent = conn->transport->ops->writev(conn->transport, &iov[0], + iov_idx, len, + 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; + 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) { + struct task_struct *task; + + t = conn->transport; + task = t->handler; + if (task) + ksmbd_debug(CONN, "Stop session handler %s/%d\n", + task->comm, task_pid_nr(task)); + 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); +} |