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-rw-r--r--fs/smb/client/cifstransport.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/fs/smb/client/cifstransport.c b/fs/smb/client/cifstransport.c
new file mode 100644
index 000000000000..352dafb888dd
--- /dev/null
+++ b/fs/smb/client/cifstransport.c
@@ -0,0 +1,566 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ *
+ * Copyright (C) International Business Machines Corp., 2002,2008
+ * Author(s): Steve French (sfrench@us.ibm.com)
+ * Jeremy Allison (jra@samba.org) 2006.
+ *
+ */
+
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <linux/gfp.h>
+#include <linux/wait.h>
+#include <linux/net.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#include <linux/tcp.h>
+#include <linux/bvec.h>
+#include <linux/highmem.h>
+#include <linux/uaccess.h>
+#include <linux/processor.h>
+#include <linux/mempool.h>
+#include <linux/sched/signal.h>
+#include <linux/task_io_accounting_ops.h>
+#include "cifspdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "cifs_debug.h"
+#include "smb2proto.h"
+#include "smbdirect.h"
+#include "compress.h"
+
+/* Max number of iovectors we can use off the stack when sending requests. */
+#define CIFS_MAX_IOV_SIZE 8
+
+static struct mid_q_entry *
+alloc_mid(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
+{
+ struct mid_q_entry *temp;
+
+ if (server == NULL) {
+ cifs_dbg(VFS, "%s: null TCP session\n", __func__);
+ return NULL;
+ }
+
+ temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
+ memset(temp, 0, sizeof(struct mid_q_entry));
+ kref_init(&temp->refcount);
+ temp->mid = get_mid(smb_buffer);
+ temp->pid = current->pid;
+ temp->command = cpu_to_le16(smb_buffer->Command);
+ cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
+ /* easier to use jiffies */
+ /* when mid allocated can be before when sent */
+ temp->when_alloc = jiffies;
+ temp->server = server;
+
+ /*
+ * The default is for the mid to be synchronous, so the
+ * default callback just wakes up the current task.
+ */
+ get_task_struct(current);
+ temp->creator = current;
+ temp->callback = cifs_wake_up_task;
+ temp->callback_data = current;
+
+ atomic_inc(&mid_count);
+ temp->mid_state = MID_REQUEST_ALLOCATED;
+ return temp;
+}
+
+int
+smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
+ unsigned int smb_buf_length)
+{
+ struct kvec iov[2];
+ struct smb_rqst rqst = { .rq_iov = iov,
+ .rq_nvec = 2 };
+
+ iov[0].iov_base = smb_buffer;
+ iov[0].iov_len = 4;
+ iov[1].iov_base = (char *)smb_buffer + 4;
+ iov[1].iov_len = smb_buf_length;
+
+ return __smb_send_rqst(server, 1, &rqst);
+}
+
+static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
+ struct mid_q_entry **ppmidQ)
+{
+ spin_lock(&ses->ses_lock);
+ if (ses->ses_status == SES_NEW) {
+ if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
+ (in_buf->Command != SMB_COM_NEGOTIATE)) {
+ spin_unlock(&ses->ses_lock);
+ return -EAGAIN;
+ }
+ /* else ok - we are setting up session */
+ }
+
+ if (ses->ses_status == SES_EXITING) {
+ /* check if SMB session is bad because we are setting it up */
+ if (in_buf->Command != SMB_COM_LOGOFF_ANDX) {
+ spin_unlock(&ses->ses_lock);
+ return -EAGAIN;
+ }
+ /* else ok - we are shutting down session */
+ }
+ spin_unlock(&ses->ses_lock);
+
+ *ppmidQ = alloc_mid(in_buf, ses->server);
+ if (*ppmidQ == NULL)
+ return -ENOMEM;
+ spin_lock(&ses->server->mid_queue_lock);
+ list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
+ spin_unlock(&ses->server->mid_queue_lock);
+ return 0;
+}
+
+struct mid_q_entry *
+cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+ int rc;
+ struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
+ struct mid_q_entry *mid;
+
+ if (rqst->rq_iov[0].iov_len != 4 ||
+ rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
+ return ERR_PTR(-EIO);
+
+ /* enable signing if server requires it */
+ if (server->sign)
+ hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
+ mid = alloc_mid(hdr, server);
+ if (mid == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
+ if (rc) {
+ release_mid(mid);
+ return ERR_PTR(rc);
+ }
+
+ return mid;
+}
+
+/*
+ *
+ * Send an SMB Request. No response info (other than return code)
+ * needs to be parsed.
+ *
+ * flags indicate the type of request buffer and how long to wait
+ * and whether to log NT STATUS code (error) before mapping it to POSIX error
+ *
+ */
+int
+SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
+ char *in_buf, int flags)
+{
+ int rc;
+ struct kvec iov[1];
+ struct kvec rsp_iov;
+ int resp_buf_type;
+
+ iov[0].iov_base = in_buf;
+ iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
+ flags |= CIFS_NO_RSP_BUF;
+ rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
+ cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
+
+ return rc;
+}
+
+int
+cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+ bool log_error)
+{
+ unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
+
+ dump_smb(mid->resp_buf, min_t(u32, 92, len));
+
+ /* convert the length into a more usable form */
+ if (server->sign) {
+ struct kvec iov[2];
+ int rc = 0;
+ struct smb_rqst rqst = { .rq_iov = iov,
+ .rq_nvec = 2 };
+
+ iov[0].iov_base = mid->resp_buf;
+ iov[0].iov_len = 4;
+ iov[1].iov_base = (char *)mid->resp_buf + 4;
+ iov[1].iov_len = len - 4;
+ /* FIXME: add code to kill session */
+ rc = cifs_verify_signature(&rqst, server,
+ mid->sequence_number);
+ if (rc)
+ cifs_server_dbg(VFS, "SMB signature verification returned error = %d\n",
+ rc);
+ }
+
+ /* BB special case reconnect tid and uid here? */
+ return map_and_check_smb_error(mid, log_error);
+}
+
+struct mid_q_entry *
+cifs_setup_request(struct cifs_ses *ses, struct TCP_Server_Info *ignored,
+ struct smb_rqst *rqst)
+{
+ int rc;
+ struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
+ struct mid_q_entry *mid;
+
+ if (rqst->rq_iov[0].iov_len != 4 ||
+ rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
+ return ERR_PTR(-EIO);
+
+ rc = allocate_mid(ses, hdr, &mid);
+ if (rc)
+ return ERR_PTR(rc);
+ rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
+ if (rc) {
+ delete_mid(mid);
+ return ERR_PTR(rc);
+ }
+ return mid;
+}
+
+int
+SendReceive2(const unsigned int xid, struct cifs_ses *ses,
+ struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
+ const int flags, struct kvec *resp_iov)
+{
+ struct smb_rqst rqst;
+ struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
+ int rc;
+
+ if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
+ new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
+ GFP_KERNEL);
+ if (!new_iov) {
+ /* otherwise cifs_send_recv below sets resp_buf_type */
+ *resp_buf_type = CIFS_NO_BUFFER;
+ return -ENOMEM;
+ }
+ } else
+ new_iov = s_iov;
+
+ /* 1st iov is a RFC1001 length followed by the rest of the packet */
+ memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
+
+ new_iov[0].iov_base = new_iov[1].iov_base;
+ new_iov[0].iov_len = 4;
+ new_iov[1].iov_base += 4;
+ new_iov[1].iov_len -= 4;
+
+ memset(&rqst, 0, sizeof(struct smb_rqst));
+ rqst.rq_iov = new_iov;
+ rqst.rq_nvec = n_vec + 1;
+
+ rc = cifs_send_recv(xid, ses, ses->server,
+ &rqst, resp_buf_type, flags, resp_iov);
+ if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
+ kfree(new_iov);
+ return rc;
+}
+
+int
+SendReceive(const unsigned int xid, struct cifs_ses *ses,
+ struct smb_hdr *in_buf, struct smb_hdr *out_buf,
+ int *pbytes_returned, const int flags)
+{
+ int rc = 0;
+ struct mid_q_entry *midQ;
+ unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
+ struct kvec iov = { .iov_base = in_buf, .iov_len = len };
+ struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
+ struct cifs_credits credits = { .value = 1, .instance = 0 };
+ struct TCP_Server_Info *server;
+
+ if (ses == NULL) {
+ cifs_dbg(VFS, "Null smb session\n");
+ return -EIO;
+ }
+ server = ses->server;
+ if (server == NULL) {
+ cifs_dbg(VFS, "Null tcp session\n");
+ return -EIO;
+ }
+
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsExiting) {
+ spin_unlock(&server->srv_lock);
+ return -ENOENT;
+ }
+ spin_unlock(&server->srv_lock);
+
+ /* Ensure that we do not send more than 50 overlapping requests
+ to the same server. We may make this configurable later or
+ use ses->maxReq */
+
+ if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
+ cifs_server_dbg(VFS, "Invalid length, greater than maximum frame, %d\n",
+ len);
+ return -EIO;
+ }
+
+ rc = wait_for_free_request(server, flags, &credits.instance);
+ if (rc)
+ return rc;
+
+ /* make sure that we sign in the same order that we send on this socket
+ and avoid races inside tcp sendmsg code that could cause corruption
+ of smb data */
+
+ cifs_server_lock(server);
+
+ rc = allocate_mid(ses, in_buf, &midQ);
+ if (rc) {
+ cifs_server_unlock(server);
+ /* Update # of requests on wire to server */
+ add_credits(server, &credits, 0);
+ return rc;
+ }
+
+ rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
+ if (rc) {
+ cifs_server_unlock(server);
+ goto out;
+ }
+
+ midQ->mid_state = MID_REQUEST_SUBMITTED;
+
+ rc = smb_send(server, in_buf, len);
+ cifs_save_when_sent(midQ);
+
+ if (rc < 0)
+ server->sequence_number -= 2;
+
+ cifs_server_unlock(server);
+
+ if (rc < 0)
+ goto out;
+
+ rc = wait_for_response(server, midQ);
+ if (rc != 0) {
+ send_cancel(server, &rqst, midQ);
+ spin_lock(&server->mid_queue_lock);
+ if (midQ->mid_state == MID_REQUEST_SUBMITTED ||
+ midQ->mid_state == MID_RESPONSE_RECEIVED) {
+ /* no longer considered to be "in-flight" */
+ midQ->callback = release_mid;
+ spin_unlock(&server->mid_queue_lock);
+ add_credits(server, &credits, 0);
+ return rc;
+ }
+ spin_unlock(&server->mid_queue_lock);
+ }
+
+ rc = cifs_sync_mid_result(midQ, server);
+ if (rc != 0) {
+ add_credits(server, &credits, 0);
+ return rc;
+ }
+
+ if (!midQ->resp_buf || !out_buf ||
+ midQ->mid_state != MID_RESPONSE_READY) {
+ rc = -EIO;
+ cifs_server_dbg(VFS, "Bad MID state?\n");
+ goto out;
+ }
+
+ *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
+ memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
+ rc = cifs_check_receive(midQ, server, 0);
+out:
+ delete_mid(midQ);
+ add_credits(server, &credits, 0);
+
+ return rc;
+}
+
+/* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
+ blocking lock to return. */
+
+static int
+send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
+ struct smb_hdr *in_buf,
+ struct smb_hdr *out_buf)
+{
+ int bytes_returned;
+ struct cifs_ses *ses = tcon->ses;
+ LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
+
+ /* We just modify the current in_buf to change
+ the type of lock from LOCKING_ANDX_SHARED_LOCK
+ or LOCKING_ANDX_EXCLUSIVE_LOCK to
+ LOCKING_ANDX_CANCEL_LOCK. */
+
+ pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
+ pSMB->Timeout = 0;
+ pSMB->hdr.Mid = get_next_mid(ses->server);
+
+ return SendReceive(xid, ses, in_buf, out_buf,
+ &bytes_returned, 0);
+}
+
+int
+SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
+ struct smb_hdr *in_buf, struct smb_hdr *out_buf,
+ int *pbytes_returned)
+{
+ int rc = 0;
+ int rstart = 0;
+ struct mid_q_entry *midQ;
+ struct cifs_ses *ses;
+ unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
+ struct kvec iov = { .iov_base = in_buf, .iov_len = len };
+ struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
+ unsigned int instance;
+ struct TCP_Server_Info *server;
+
+ if (tcon == NULL || tcon->ses == NULL) {
+ cifs_dbg(VFS, "Null smb session\n");
+ return -EIO;
+ }
+ ses = tcon->ses;
+ server = ses->server;
+
+ if (server == NULL) {
+ cifs_dbg(VFS, "Null tcp session\n");
+ return -EIO;
+ }
+
+ spin_lock(&server->srv_lock);
+ if (server->tcpStatus == CifsExiting) {
+ spin_unlock(&server->srv_lock);
+ return -ENOENT;
+ }
+ spin_unlock(&server->srv_lock);
+
+ /* Ensure that we do not send more than 50 overlapping requests
+ to the same server. We may make this configurable later or
+ use ses->maxReq */
+
+ if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
+ cifs_tcon_dbg(VFS, "Invalid length, greater than maximum frame, %d\n",
+ len);
+ return -EIO;
+ }
+
+ rc = wait_for_free_request(server, CIFS_BLOCKING_OP, &instance);
+ if (rc)
+ return rc;
+
+ /* make sure that we sign in the same order that we send on this socket
+ and avoid races inside tcp sendmsg code that could cause corruption
+ of smb data */
+
+ cifs_server_lock(server);
+
+ rc = allocate_mid(ses, in_buf, &midQ);
+ if (rc) {
+ cifs_server_unlock(server);
+ return rc;
+ }
+
+ rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
+ if (rc) {
+ delete_mid(midQ);
+ cifs_server_unlock(server);
+ return rc;
+ }
+
+ midQ->mid_state = MID_REQUEST_SUBMITTED;
+ rc = smb_send(server, in_buf, len);
+ cifs_save_when_sent(midQ);
+
+ if (rc < 0)
+ server->sequence_number -= 2;
+
+ cifs_server_unlock(server);
+
+ if (rc < 0) {
+ delete_mid(midQ);
+ return rc;
+ }
+
+ /* Wait for a reply - allow signals to interrupt. */
+ rc = wait_event_interruptible(server->response_q,
+ (!(midQ->mid_state == MID_REQUEST_SUBMITTED ||
+ midQ->mid_state == MID_RESPONSE_RECEIVED)) ||
+ ((server->tcpStatus != CifsGood) &&
+ (server->tcpStatus != CifsNew)));
+
+ /* Were we interrupted by a signal ? */
+ spin_lock(&server->srv_lock);
+ if ((rc == -ERESTARTSYS) &&
+ (midQ->mid_state == MID_REQUEST_SUBMITTED ||
+ midQ->mid_state == MID_RESPONSE_RECEIVED) &&
+ ((server->tcpStatus == CifsGood) ||
+ (server->tcpStatus == CifsNew))) {
+ spin_unlock(&server->srv_lock);
+
+ if (in_buf->Command == SMB_COM_TRANSACTION2) {
+ /* POSIX lock. We send a NT_CANCEL SMB to cause the
+ blocking lock to return. */
+ rc = send_cancel(server, &rqst, midQ);
+ if (rc) {
+ delete_mid(midQ);
+ return rc;
+ }
+ } else {
+ /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
+ to cause the blocking lock to return. */
+
+ rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
+
+ /* If we get -ENOLCK back the lock may have
+ already been removed. Don't exit in this case. */
+ if (rc && rc != -ENOLCK) {
+ delete_mid(midQ);
+ return rc;
+ }
+ }
+
+ rc = wait_for_response(server, midQ);
+ if (rc) {
+ send_cancel(server, &rqst, midQ);
+ spin_lock(&server->mid_queue_lock);
+ if (midQ->mid_state == MID_REQUEST_SUBMITTED ||
+ midQ->mid_state == MID_RESPONSE_RECEIVED) {
+ /* no longer considered to be "in-flight" */
+ midQ->callback = release_mid;
+ spin_unlock(&server->mid_queue_lock);
+ return rc;
+ }
+ spin_unlock(&server->mid_queue_lock);
+ }
+
+ /* We got the response - restart system call. */
+ rstart = 1;
+ spin_lock(&server->srv_lock);
+ }
+ spin_unlock(&server->srv_lock);
+
+ rc = cifs_sync_mid_result(midQ, server);
+ if (rc != 0)
+ return rc;
+
+ /* rcvd frame is ok */
+ if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_READY) {
+ rc = -EIO;
+ cifs_tcon_dbg(VFS, "Bad MID state?\n");
+ goto out;
+ }
+
+ *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
+ memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
+ rc = cifs_check_receive(midQ, server, 0);
+out:
+ delete_mid(midQ);
+ if (rstart && rc == -EACCES)
+ return -ERESTARTSYS;
+ return rc;
+}
generated by cgit (git 2.34.1) at 2025-08-09 21:17:26 +0000