CIFS: Implement follow_link for nounix CIFS mounts (d244bf2d) · Commits · jan.koester / Linux

fs/cifs/cifspdu.h

+6 −5

Original line number	Original line	Diff line number	Diff line
	@@ -1495,11 +1495,12 @@ struct reparse_data {
	__u32 ReparseTag;		__u32 ReparseTag;
	__u16 ReparseDataLength;		__u16 ReparseDataLength;
	__u16 Reserved;		__u16 Reserved;
	__u16 AltNameOffset;		__u16 SubstituteNameOffset;
	__u16 AltNameLen;		__u16 SubstituteNameLength;
	__u16 TargetNameOffset;		__u16 PrintNameOffset;
	__u16 TargetNameLen;		__u16 PrintNameLength;
	char LinkNamesBuf[1];		__u32 Flags;
			char PathBuffer[0];
	} __attribute__((packed));		} __attribute__((packed));

	struct cifs_quota_data {		struct cifs_quota_data {

fs/cifs/cifsproto.h

+3 −7

Original line number	Original line	Diff line number	Diff line
	@@ -357,13 +357,9 @@ extern int CIFSSMBUnixQuerySymLink(const unsigned int xid,
	struct cifs_tcon *tcon,		struct cifs_tcon *tcon,
	const unsigned char searchName, char *syminfo,		const unsigned char searchName, char *syminfo,
	const struct nls_table *nls_codepage);		const struct nls_table *nls_codepage);
	#ifdef CONFIG_CIFS_SYMLINK_EXPERIMENTAL		extern int CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
	extern int CIFSSMBQueryReparseLinkInfo(const unsigned int xid,		__u16 fid, char **symlinkinfo,
	struct cifs_tcon *tcon,
	const unsigned char *searchName,
	char *symlinkinfo, const int buflen, __u16 fid,
	const struct nls_table *nls_codepage);		const struct nls_table *nls_codepage);
	#endif /* temporarily unused until cifs_symlink fixed */
	extern int CIFSSMBOpen(const unsigned int xid, struct cifs_tcon *tcon,		extern int CIFSSMBOpen(const unsigned int xid, struct cifs_tcon *tcon,
	const char *fileName, const int disposition,		const char *fileName, const int disposition,
	const int access_flags, const int omode,		const int access_flags, const int omode,

fs/cifs/cifssmb.c

+51 −59

Original line number	Original line	Diff line number	Diff line
	@@ -3067,7 +3067,6 @@ CIFSSMBUnixQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
	return rc;		return rc;
	}		}

	#ifdef CONFIG_CIFS_SYMLINK_EXPERIMENTAL
	/*		/*
	* Recent Windows versions now create symlinks more frequently		* Recent Windows versions now create symlinks more frequently
	* and they use the "reparse point" mechanism below. We can of course		* and they use the "reparse point" mechanism below. We can of course
	@@ -3079,18 +3078,22 @@ CIFSSMBUnixQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
	* it is not compiled in by default until callers fixed up and more tested.		* it is not compiled in by default until callers fixed up and more tested.
	*/		*/
	int		int
	CIFSSMBQueryReparseLinkInfo(const unsigned int xid, struct cifs_tcon *tcon,		CIFSSMBQuerySymLink(const unsigned int xid, struct cifs_tcon *tcon,
	const unsigned char *searchName,		__u16 fid, char **symlinkinfo,
	char *symlinkinfo, const int buflen, __u16 fid,
	const struct nls_table *nls_codepage)		const struct nls_table *nls_codepage)
	{		{
	int rc = 0;		int rc = 0;
	int bytes_returned;		int bytes_returned;
	struct smb_com_transaction_ioctl_req *pSMB;		struct smb_com_transaction_ioctl_req *pSMB;
	struct smb_com_transaction_ioctl_rsp *pSMBr;		struct smb_com_transaction_ioctl_rsp *pSMBr;
			bool is_unicode;
			unsigned int sub_len;
			char *sub_start;
			struct reparse_data *reparse_buf;
			__u32 data_offset, data_count;
			char *end_of_smb;

	cifs_dbg(FYI, "In Windows reparse style QueryLink for path %s\n",		cifs_dbg(FYI, "In Windows reparse style QueryLink for fid %u\n", fid);
	searchName);
	rc = smb_init(SMB_COM_NT_TRANSACT, 23, tcon, (void **) &pSMB,		rc = smb_init(SMB_COM_NT_TRANSACT, 23, tcon, (void **) &pSMB,
	(void **) &pSMBr);		(void **) &pSMBr);
	if (rc)		if (rc)
	@@ -3119,66 +3122,55 @@ CIFSSMBQueryReparseLinkInfo(const unsigned int xid, struct cifs_tcon *tcon,
	(struct smb_hdr *) pSMBr, &bytes_returned, 0);		(struct smb_hdr *) pSMBr, &bytes_returned, 0);
	if (rc) {		if (rc) {
	cifs_dbg(FYI, "Send error in QueryReparseLinkInfo = %d\n", rc);		cifs_dbg(FYI, "Send error in QueryReparseLinkInfo = %d\n", rc);
	} else { /* decode response */		goto qreparse_out;
	__u32 data_offset = le32_to_cpu(pSMBr->DataOffset);		}
	__u32 data_count = le32_to_cpu(pSMBr->DataCount);
			data_offset = le32_to_cpu(pSMBr->DataOffset);
			data_count = le32_to_cpu(pSMBr->DataCount);
	if (get_bcc(&pSMBr->hdr) < 2 \|\| data_offset > 512) {		if (get_bcc(&pSMBr->hdr) < 2 \|\| data_offset > 512) {
	/* BB also check enough total bytes returned */		/* BB also check enough total bytes returned */
	rc = -EIO; /* bad smb */		rc = -EIO; /* bad smb */
	goto qreparse_out;		goto qreparse_out;
	}		}
	if (data_count && (data_count < 2048)) {		if (!data_count \|\| (data_count > 2048)) {
	char end_of_smb = 2 / sizeof byte count */ +
	get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;

	struct reparse_data *reparse_buf =
	(struct reparse_data *)
	((char *)&pSMBr->hdr.Protocol
	+ data_offset);
	if ((char *)reparse_buf >= end_of_smb) {
	rc = -EIO;		rc = -EIO;
			cifs_dbg(FYI, "Invalid return data count on get reparse info ioctl\n");
	goto qreparse_out;		goto qreparse_out;
	}		}
	if ((reparse_buf->LinkNamesBuf +		end_of_smb = 2 + get_bcc(&pSMBr->hdr) + (char *)&pSMBr->ByteCount;
	reparse_buf->TargetNameOffset +		reparse_buf = (struct reparse_data *)
	reparse_buf->TargetNameLen) > end_of_smb) {		((char *)&pSMBr->hdr.Protocol + data_offset);
	cifs_dbg(FYI, "reparse buf beyond SMB\n");		if ((char *)reparse_buf >= end_of_smb) {
	rc = -EIO;		rc = -EIO;
	goto qreparse_out;		goto qreparse_out;
	}		}
			if ((reparse_buf->PathBuffer + reparse_buf->PrintNameOffset +
	if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) {		reparse_buf->PrintNameLength) > end_of_smb) {
	cifs_from_ucs2(symlinkinfo, (__le16 *)		cifs_dbg(FYI, "reparse buf beyond SMB\n");
	(reparse_buf->LinkNamesBuf +
	reparse_buf->TargetNameOffset),
	buflen,
	reparse_buf->TargetNameLen,
	nls_codepage, 0);
	} else { /* ASCII names */
	strncpy(symlinkinfo,
	reparse_buf->LinkNamesBuf +
	reparse_buf->TargetNameOffset,
	min_t(const int, buflen,
	reparse_buf->TargetNameLen));
	}
	} else {
	rc = -EIO;		rc = -EIO;
	cifs_dbg(FYI, "Invalid return data count on get reparse info ioctl\n");		goto qreparse_out;
	}
	symlinkinfo[buflen] = 0; /* just in case so the caller
	does not go off the end of the buffer */
	cifs_dbg(FYI, "readlink result - %s\n", symlinkinfo);
	}		}
			sub_start = reparse_buf->SubstituteNameOffset + reparse_buf->PathBuffer;
			sub_len = reparse_buf->SubstituteNameLength;
			if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE)
			is_unicode = true;
			else
			is_unicode = false;

			/* BB FIXME investigate remapping reserved chars here */
			*symlinkinfo = cifs_strndup_from_utf16(sub_start, sub_len, is_unicode,
			nls_codepage);
			if (!*symlinkinfo)
			rc = -ENOMEM;
	qreparse_out:		qreparse_out:
	cifs_buf_release(pSMB);		cifs_buf_release(pSMB);

	/* Note: On -EAGAIN error only caller can retry on handle based calls		/*
	since file handle passed in no longer valid */		* Note: On -EAGAIN error only caller can retry on handle based calls
			* since file handle passed in no longer valid.
			*/
	return rc;		return rc;
	}		}
	#endif /* CIFS_SYMLINK_EXPERIMENTAL / / BB temporarily unused */

	#ifdef CONFIG_CIFS_POSIX		#ifdef CONFIG_CIFS_POSIX

fs/cifs/smb1ops.c

+32 −0

Original line number	Original line	Diff line number	Diff line
	@@ -881,6 +881,37 @@ cifs_mand_lock(const unsigned int xid, struct cifsFileInfo *cfile, __u64 offset,
	(__u8)type, wait, 0);		(__u8)type, wait, 0);
	}		}

			static int
			cifs_query_symlink(const unsigned int xid, struct cifs_tcon *tcon,
			const char full_path, char *target_path,
			struct cifs_sb_info *cifs_sb)
			{
			int rc;
			int oplock = 0;
			__u16 netfid;

			cifs_dbg(FYI, "%s: path: %s\n", __func__, full_path);

			rc = CIFSSMBOpen(xid, tcon, full_path, FILE_OPEN,
			FILE_READ_ATTRIBUTES, OPEN_REPARSE_POINT, &netfid,
			&oplock, NULL, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
			if (rc)
			return rc;

			rc = CIFSSMBQuerySymLink(xid, tcon, netfid, target_path,
			cifs_sb->local_nls);
			if (rc) {
			CIFSSMBClose(xid, tcon, netfid);
			return rc;
			}

			convert_delimiter(*target_path, '/');
			CIFSSMBClose(xid, tcon, netfid);
			cifs_dbg(FYI, "%s: target path: %s\n", __func__, *target_path);
			return rc;
			}

	struct smb_version_operations smb1_operations = {		struct smb_version_operations smb1_operations = {
	.send_cancel = send_nt_cancel,		.send_cancel = send_nt_cancel,
	.compare_fids = cifs_compare_fids,		.compare_fids = cifs_compare_fids,
	@@ -927,6 +958,7 @@ struct smb_version_operations smb1_operations = {
	.rename_pending_delete = cifs_rename_pending_delete,		.rename_pending_delete = cifs_rename_pending_delete,
	.rename = CIFSSMBRename,		.rename = CIFSSMBRename,
	.create_hardlink = CIFSCreateHardLink,		.create_hardlink = CIFSCreateHardLink,
			.query_symlink = cifs_query_symlink,
	.open = cifs_open_file,		.open = cifs_open_file,
	.set_fid = cifs_set_fid,		.set_fid = cifs_set_fid,
	.close = cifs_close_file,		.close = cifs_close_file,