CIFS: Make transport routines work with SMB2

Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/smb2transport.c b/fs/cifs/smb2transport.c
new file mode 100644
index 0000000..b4b6b9a
--- /dev/null
+++ b/fs/cifs/smb2transport.c
@@ -0,0 +1,151 @@
+/*
+ *   fs/cifs/smb2transport.c
+ *
+ *   Copyright (C) International Business Machines  Corp., 2002, 2011
+ *                 Etersoft, 2012
+ *   Author(s): Steve French (sfrench@us.ibm.com)
+ *              Jeremy Allison (jra@samba.org) 2006
+ *              Pavel Shilovsky (pshilovsky@samba.org) 2012
+ *
+ *   This library is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Lesser General Public License as published
+ *   by the Free Software Foundation; either version 2.1 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This library is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+ *   the GNU Lesser General Public License for more details.
+ *
+ *   You should have received a copy of the GNU Lesser General Public License
+ *   along with this library; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/fs.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/net.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <linux/mempool.h>
+#include "smb2pdu.h"
+#include "cifsglob.h"
+#include "cifsproto.h"
+#include "smb2proto.h"
+#include "cifs_debug.h"
+#include "smb2status.h"
+
+/*
+ * Set message id for the request. Should be called after wait_for_free_request
+ * and when srv_mutex is held.
+ */
+static inline void
+smb2_seq_num_into_buf(struct TCP_Server_Info *server, struct smb2_hdr *hdr)
+{
+	hdr->MessageId = get_next_mid(server);
+}
+
+static struct mid_q_entry *
+smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
+		     struct TCP_Server_Info *server)
+{
+	struct mid_q_entry *temp;
+
+	if (server == NULL) {
+		cERROR(1, "Null TCP session in smb2_mid_entry_alloc");
+		return NULL;
+	}
+
+	temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
+	if (temp == NULL)
+		return temp;
+	else {
+		memset(temp, 0, sizeof(struct mid_q_entry));
+		temp->mid = smb_buffer->MessageId;	/* always LE */
+		temp->pid = current->pid;
+		temp->command = smb_buffer->Command;	/* Always LE */
+		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.
+		 */
+		temp->callback = cifs_wake_up_task;
+		temp->callback_data = current;
+	}
+
+	atomic_inc(&midCount);
+	temp->mid_state = MID_REQUEST_ALLOCATED;
+	return temp;
+}
+
+static int
+smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_hdr *buf,
+		   struct mid_q_entry **mid)
+{
+	if (ses->server->tcpStatus == CifsExiting)
+		return -ENOENT;
+
+	if (ses->server->tcpStatus == CifsNeedReconnect) {
+		cFYI(1, "tcp session dead - return to caller to retry");
+		return -EAGAIN;
+	}
+
+	if (ses->status != CifsGood) {
+		/* check if SMB2 session is bad because we are setting it up */
+		if ((buf->Command != SMB2_SESSION_SETUP) &&
+		    (buf->Command != SMB2_NEGOTIATE))
+			return -EAGAIN;
+		/* else ok - we are setting up session */
+	}
+	*mid = smb2_mid_entry_alloc(buf, ses->server);
+	if (*mid == NULL)
+		return -ENOMEM;
+	spin_lock(&GlobalMid_Lock);
+	list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
+	spin_unlock(&GlobalMid_Lock);
+	return 0;
+}
+
+int
+smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
+		   bool log_error)
+{
+	unsigned int len = get_rfc1002_length(mid->resp_buf);
+
+	dump_smb(mid->resp_buf, min_t(u32, 80, len));
+	/* convert the length into a more usable form */
+	/* BB - uncomment with SMB2 signing implementation */
+	/* if ((len > 24) &&
+	    (server->sec_mode & (SECMODE_SIGN_REQUIRED|SECMODE_SIGN_ENABLED))) {
+		if (smb2_verify_signature(mid->resp_buf, server))
+			cERROR(1, "Unexpected SMB signature");
+	} */
+
+	return map_smb2_to_linux_error(mid->resp_buf, log_error);
+}
+
+int
+smb2_setup_request(struct cifs_ses *ses, struct kvec *iov,
+		   unsigned int nvec, struct mid_q_entry **ret_mid)
+{
+	int rc;
+	struct smb2_hdr *hdr = (struct smb2_hdr *)iov[0].iov_base;
+	struct mid_q_entry *mid;
+
+	smb2_seq_num_into_buf(ses->server, hdr);
+
+	rc = smb2_get_mid_entry(ses, hdr, &mid);
+	if (rc)
+		return rc;
+	/* rc = smb2_sign_smb2(iov, nvec, ses->server);
+	if (rc)
+		delete_mid(mid); */
+	*ret_mid = mid;
+	return rc;
+}
+
+/* BB add missing functions here */