Commit 2503a0db authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Pavel Shilovsky
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CIFS: Add SMB2 support for is_path_accessible 



that needs for a successful mount through SMB2 protocol.

Signed-off-by: default avatarPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent 68889f26

fs/cifs/cifs_unicode.c

+61 −0
Original line number Diff line number Diff line
@@ -330,3 +330,64 @@ cifsConvertToUTF16(__le16 *target, const char *source, int srclen, 
ctoUTF16_out:

	return i;

}



#ifdef CONFIG_CIFS_SMB2

/*

 * cifs_local_to_utf16_bytes - how long will a string be after conversion?

 * @from - pointer to input string

 * @maxbytes - don't go past this many bytes of input string

 * @codepage - source codepage

 *

 * Walk a string and return the number of bytes that the string will

 * be after being converted to the given charset, not including any null

 * termination required. Don't walk past maxbytes in the source buffer.

 */



static int

cifs_local_to_utf16_bytes(const char *from, int len,

			  const struct nls_table *codepage)

{

	int charlen;

	int i;

	wchar_t wchar_to;



	for (i = 0; len && *from; i++, from += charlen, len -= charlen) {

		charlen = codepage->char2uni(from, len, &wchar_to);

		/* Failed conversion defaults to a question mark */

		if (charlen < 1)

			charlen = 1;

	}

	return 2 * i; /* UTF16 characters are two bytes */

}



/*

 * cifs_strndup_to_utf16 - copy a string to wire format from the local codepage

 * @src - source string

 * @maxlen - don't walk past this many bytes in the source string

 * @utf16_len - the length of the allocated string in bytes (including null)

 * @cp - source codepage

 * @remap - map special chars

 *

 * Take a string convert it from the local codepage to UTF16 and

 * put it in a new buffer. Returns a pointer to the new string or NULL on

 * error.

 */

__le16 *

cifs_strndup_to_utf16(const char *src, const int maxlen, int *utf16_len,

		      const struct nls_table *cp, int remap)

{

	int len;

	__le16 *dst;



	len = cifs_local_to_utf16_bytes(src, maxlen, cp);

	len += 2; /* NULL */

	dst = kmalloc(len, GFP_KERNEL);

	if (!dst) {

		*utf16_len = 0;

		return NULL;

	}

	cifsConvertToUTF16(dst, src, strlen(src), cp, remap);

	*utf16_len = len;

	return dst;

}

#endif /* CONFIG_CIFS_SMB2 */

fs/cifs/cifs_unicode.h

+5 −0
Original line number Diff line number Diff line
@@ -84,6 +84,11 @@ char *cifs_strndup_from_utf16(const char *src, const int maxlen, 
			      const struct nls_table *codepage);

extern int cifsConvertToUTF16(__le16 *target, const char *source, int maxlen,

			      const struct nls_table *cp, int mapChars);

#ifdef CONFIG_CIFS_SMB2

extern __le16 *cifs_strndup_to_utf16(const char *src, const int maxlen,

				     int *utf16_len, const struct nls_table *cp,

				     int remap);

#endif /* CONFIG_CIFS_SMB2 */

#endif



/*

fs/cifs/smb2misc.c

+25 −0
Original line number Diff line number Diff line
@@ -230,6 +230,11 @@ smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr) 
		    ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);

		break;

	case SMB2_CREATE:

		*off = le32_to_cpu(

		    ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);

		*len = le32_to_cpu(

		    ((struct smb2_create_rsp *)hdr)->CreateContextsLength);

		break;

	case SMB2_READ:

	case SMB2_QUERY_INFO:

	case SMB2_QUERY_DIRECTORY:
@@ -315,3 +320,23 @@ smb2_calc_size(struct smb2_hdr *hdr) 
	cFYI(1, "SMB2 len %d", len);

	return len;

}



/* Note: caller must free return buffer */

__le16 *

cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)

{

	int len;

	const char *start_of_path;

	__le16 *to;



	/* Windows doesn't allow paths beginning with \ */

	if (from[0] == '\\')

		start_of_path = from + 1;

	else

		start_of_path = from;

	to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,

				   cifs_sb->local_nls,

				   cifs_sb->mnt_cifs_flags &

					CIFS_MOUNT_MAP_SPECIAL_CHR);

	return to;

}

fs/cifs/smb2ops.c

+25 −0
Original line number Diff line number Diff line
@@ -157,6 +157,30 @@ smb2_negotiate(const unsigned int xid, struct cifs_ses *ses) 
	return rc;

}



static int

smb2_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,

			struct cifs_sb_info *cifs_sb, const char *full_path)

{

	int rc;

	__u64 persistent_fid, volatile_fid;

	__le16 *utf16_path;



	utf16_path = cifs_convert_path_to_utf16(full_path, cifs_sb);

	if (!utf16_path)

		return -ENOMEM;



	rc = SMB2_open(xid, tcon, utf16_path, &persistent_fid, &volatile_fid,

		       FILE_READ_ATTRIBUTES, FILE_OPEN, 0, 0);

	if (rc) {

		kfree(utf16_path);

		return rc;

	}



	rc = SMB2_close(xid, tcon, persistent_fid, volatile_fid);

	kfree(utf16_path);

	return rc;

}



struct smb_version_operations smb21_operations = {

	.setup_request = smb2_setup_request,

	.check_receive = smb2_check_receive,
@@ -174,6 +198,7 @@ struct smb_version_operations smb21_operations = { 
	.logoff = SMB2_logoff,

	.tree_connect = SMB2_tcon,

	.tree_disconnect = SMB2_tdis,

	.is_path_accessible = smb2_is_path_accessible,

};



struct smb_version_values smb21_values = {

fs/cifs/smb2pdu.c

+132 −0
Original line number Diff line number Diff line
@@ -829,3 +829,135 @@ SMB2_tdis(const unsigned int xid, struct cifs_tcon *tcon) 


	return rc;

}



int

SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,

	  u64 *persistent_fid, u64 *volatile_fid, __u32 desired_access,

	  __u32 create_disposition, __u32 file_attributes, __u32 create_options)

{

	struct smb2_create_req *req;

	struct smb2_create_rsp *rsp;

	struct TCP_Server_Info *server;

	struct cifs_ses *ses = tcon->ses;

	struct kvec iov[2];

	int resp_buftype;

	int uni_path_len;

	int rc = 0;

	int num_iovecs = 2;



	cFYI(1, "create/open");



	if (ses && (ses->server))

		server = ses->server;

	else

		return -EIO;



	rc = small_smb2_init(SMB2_CREATE, tcon, (void **) &req);

	if (rc)

		return rc;



	if (enable_oplocks)

		req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_BATCH;

	else

		req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_NONE;

	req->ImpersonationLevel = IL_IMPERSONATION;

	req->DesiredAccess = cpu_to_le32(desired_access);

	/* File attributes ignored on open (used in create though) */

	req->FileAttributes = cpu_to_le32(file_attributes);

	req->ShareAccess = FILE_SHARE_ALL_LE;

	req->CreateDisposition = cpu_to_le32(create_disposition);

	req->CreateOptions = cpu_to_le32(create_options);

	uni_path_len = (2 * UniStrnlen((wchar_t *)path, PATH_MAX)) + 2;

	req->NameOffset = cpu_to_le16(sizeof(struct smb2_create_req)

			- 1 /* pad */ - 4 /* do not count rfc1001 len field */);



	iov[0].iov_base = (char *)req;

	/* 4 for rfc1002 length field */

	iov[0].iov_len = get_rfc1002_length(req) + 4;



	/* MUST set path len (NameLength) to 0 opening root of share */

	if (uni_path_len >= 4) {

		req->NameLength = cpu_to_le16(uni_path_len - 2);

		/* -1 since last byte is buf[0] which is sent below (path) */

		iov[0].iov_len--;

		iov[1].iov_len = uni_path_len;

		iov[1].iov_base = path;

		/*

		 * -1 since last byte is buf[0] which was counted in

		 * smb2_buf_len.

		 */

		inc_rfc1001_len(req, uni_path_len - 1);

	} else {

		num_iovecs = 1;

		req->NameLength = 0;

	}



	rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0);

	rsp = (struct smb2_create_rsp *)iov[0].iov_base;



	if (rc != 0) {

		cifs_stats_fail_inc(tcon, SMB2_CREATE_HE);

		goto creat_exit;

	}



	if (rsp == NULL) {

		rc = -EIO;

		goto creat_exit;

	}

	*persistent_fid = rsp->PersistentFileId;

	*volatile_fid = rsp->VolatileFileId;

creat_exit:

	free_rsp_buf(resp_buftype, rsp);

	return rc;

}



int

SMB2_close(const unsigned int xid, struct cifs_tcon *tcon,

	   u64 persistent_fid, u64 volatile_fid)

{

	struct smb2_close_req *req;

	struct smb2_close_rsp *rsp;

	struct TCP_Server_Info *server;

	struct cifs_ses *ses = tcon->ses;

	struct kvec iov[1];

	int resp_buftype;

	int rc = 0;



	cFYI(1, "Close");



	if (ses && (ses->server))

		server = ses->server;

	else

		return -EIO;



	rc = small_smb2_init(SMB2_CLOSE, tcon, (void **) &req);

	if (rc)

		return rc;



	req->PersistentFileId = persistent_fid;

	req->VolatileFileId = volatile_fid;



	iov[0].iov_base = (char *)req;

	/* 4 for rfc1002 length field */

	iov[0].iov_len = get_rfc1002_length(req) + 4;



	rc = SendReceive2(xid, ses, iov, 1, &resp_buftype, 0);

	rsp = (struct smb2_close_rsp *)iov[0].iov_base;



	if (rc != 0) {

		if (tcon)

			cifs_stats_fail_inc(tcon, SMB2_CLOSE_HE);

		goto close_exit;

	}



	if (rsp == NULL) {

		rc = -EIO;

		goto close_exit;

	}



	/* BB FIXME - decode close response, update inode for caching */



close_exit:

	free_rsp_buf(resp_buftype, rsp);

	return rc;

}