cifs: Move string length definitions to uapi

The max string length definitions for user name, domain name, password,
and share name have been moved into their own header file in uapi so the
mount helper can use autoconf to define them instead of keeping the
kernel side and userland side definitions in sync manually.  The names
have also been standardized with a "CIFS" prefix and "LEN" suffix.

Signed-off-by: Scott Lovenberg <scott.lovenberg@gmail.com>
Reviewed-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Steve French <smfrench@gmail.com>

4 files changed, 38 insertions, 16 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index ec6c3fbb29eb..633bbc5e8801 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -28,6 +28,7 @@
 #include "cifsacl.h"
 #include <crypto/internal/hash.h>
 #include <linux/scatterlist.h>
+#include <uapi/linux/cifs/cifs_mount.h>
 #ifdef CONFIG_CIFS_SMB2
 #include "smb2pdu.h"
 #endif
@@ -41,12 +42,8 @@
 #define MAX_SES_INFO 2
 #define MAX_TCON_INFO 4
 
-#define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + MAX_SHARE_SIZE + 1)
+#define MAX_TREE_SIZE (2 + MAX_SERVER_SIZE + 1 + CIFS_MAX_SHARE_LEN + 1)
 #define MAX_SERVER_SIZE 15
-#define MAX_SHARE_SIZE 80
-#define CIFS_MAX_DOMAINNAME_LEN 256 /* max domain name length */
-#define MAX_USERNAME_SIZE 256   /* reasonable maximum for current servers */
-#define MAX_PASSWORD_SIZE 512   /* max for windows seems to be 256 wide chars */
 
 #define CIFS_MIN_RCV_POOL 4
 
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 37950c65453c..b1bab99be83b 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1577,8 +1577,8 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
                         if (string == NULL)
                                 goto out_nomem;
 
-                        if (strnlen(string, MAX_USERNAME_SIZE) >
-                                                        MAX_USERNAME_SIZE) {
+                        if (strnlen(string, CIFS_MAX_USERNAME_LEN) >
+                                                        CIFS_MAX_USERNAME_LEN) {
                                 printk(KERN_WARNING "CIFS: username too long\n");
                                 goto cifs_parse_mount_err;
                         }
@@ -2223,13 +2223,13 @@ static int match_session(struct cifs_ses *ses, struct smb_vol *vol)
                 /* anything else takes username/password */
                 if (strncmp(ses->user_name,
                             vol->username ? vol->username : "",
-                            MAX_USERNAME_SIZE))
+                            CIFS_MAX_USERNAME_LEN))
                         return 0;
                 if (strlen(vol->username) != 0 &&
                     ses->password != NULL &&
                     strncmp(ses->password,
                             vol->password ? vol->password : "",
-                            MAX_PASSWORD_SIZE))
+                            CIFS_MAX_PASSWORD_LEN))
                         return 0;
         }
         return 1;
@@ -2354,7 +2354,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
         }
 
         len = delim - payload;
-        if (len > MAX_USERNAME_SIZE || len <= 0) {
+        if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
                          len);
                 rc = -EINVAL;
@@ -2371,7 +2371,7 @@ cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
         cifs_dbg(FYI, "%s: username=%s\n", __func__, vol->username);
 
         len = key->datalen - (len + 1);
-        if (len > MAX_PASSWORD_SIZE || len <= 0) {
+        if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
                 rc = -EINVAL;
                 kfree(vol->username);
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c
index 08dd37bb23aa..a0a62db0f575 100644
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -226,7 +226,7 @@ static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
                 *(bcc_ptr+1) = 0;
         } else {
                 bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
-                                            MAX_USERNAME_SIZE, nls_cp);
+                                            CIFS_MAX_USERNAME_LEN, nls_cp);
         }
         bcc_ptr += 2 * bytes_ret;
         bcc_ptr += 2; /* account for null termination */
@@ -246,8 +246,8 @@ static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
         /* BB what about null user mounts - check that we do this BB */
         /* copy user */
         if (ses->user_name != NULL) {
-                strncpy(bcc_ptr, ses->user_name, MAX_USERNAME_SIZE);
-                bcc_ptr += strnlen(ses->user_name, MAX_USERNAME_SIZE);
+                strncpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
+                bcc_ptr += strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
         }
         /* else null user mount */
         *bcc_ptr = 0;
@@ -501,7 +501,7 @@ int build_ntlmssp_auth_blob(unsigned char *pbuffer,
         } else {
                 int len;
                 len = cifs_strtoUTF16((__le16 *)tmp, ses->domainName,
-                                      MAX_USERNAME_SIZE, nls_cp);
+                                      CIFS_MAX_USERNAME_LEN, nls_cp);
                 len *= 2; /* unicode is 2 bytes each */
                 sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
                 sec_blob->DomainName.Length = cpu_to_le16(len);
@@ -517,7 +517,7 @@ int build_ntlmssp_auth_blob(unsigned char *pbuffer,
         } else {
                 int len;
                 len = cifs_strtoUTF16((__le16 *)tmp, ses->user_name,
-                                      MAX_USERNAME_SIZE, nls_cp);
+                                      CIFS_MAX_USERNAME_LEN, nls_cp);
                 len *= 2; /* unicode is 2 bytes each */
                 sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
                 sec_blob->UserName.Length = cpu_to_le16(len);
diff --git a/include/uapi/linux/cifs/cifs_mount.h b/include/uapi/linux/cifs/cifs_mount.h
new file mode 100644
index 000000000000..19063fef6219
--- /dev/null
+++ b/include/uapi/linux/cifs/cifs_mount.h
@@ -0,0 +1,25 @@
+/*
+ *   include/uapi/linux/cifs/cifs_mount.h
+ *
+ *   Author(s): Scott Lovenberg (scott.lovenberg@gmail.com)
+ *
+ *   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.
+ */
+#ifndef _CIFS_MOUNT_H
+#define _CIFS_MOUNT_H
+
+/* Max string lengths for cifs mounting options. */
+#define CIFS_MAX_DOMAINNAME_LEN 256 /* max fully qualified domain name */
+#define CIFS_MAX_USERNAME_LEN   256 /* reasonable max for current servers */
+#define CIFS_MAX_PASSWORD_LEN   512 /* Windows max seems to be 256 wide chars */
+#define CIFS_MAX_SHARE_LEN       80
+
+#endif /* _CIFS_MOUNT_H */