linux/fs/cifs/smb2pdu.h
Paulo Alcantara 76894f3e2f cifs: improve symlink handling for smb2+
When creating inode for symlink, the client used to send below
requests to fill it in:

    * create+query_info+close (STATUS_STOPPED_ON_SYMLINK)
    * create(+reparse_flag)+query_info+close (set file attrs)
    * create+ioctl(get_reparse)+close (query reparse tag)

and then for every access to the symlink dentry, the ->link() method
would send another:

    * create+ioctl(get_reparse)+close (parse symlink)

So, in order to improve:

    (i) Get rid of unnecessary roundtrips and then resolve symlinks as
	follows:

        * create+query_info+close (STATUS_STOPPED_ON_SYMLINK +
	                           parse symlink + get reparse tag)
        * create(+reparse_flag)+query_info+close (set file attrs)

    (ii) Set the resolved symlink target directly in inode->i_link and
         use simple_get_link() for ->link() to simply return it.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2022-10-13 09:36:04 -05:00

435 lines
10 KiB
C

/* SPDX-License-Identifier: LGPL-2.1 */
/*
*
* Copyright (c) International Business Machines Corp., 2009, 2013
* Etersoft, 2012
* Author(s): Steve French (sfrench@us.ibm.com)
* Pavel Shilovsky (pshilovsky@samba.org) 2012
*
*/
#ifndef _SMB2PDU_H
#define _SMB2PDU_H
#include <net/sock.h>
#include "cifsacl.h"
/* 52 transform hdr + 64 hdr + 88 create rsp */
#define SMB2_TRANSFORM_HEADER_SIZE 52
#define MAX_SMB2_HDR_SIZE 204
/* The total header size for SMB2 read and write */
#define SMB2_READWRITE_PDU_HEADER_SIZE (48 + sizeof(struct smb2_hdr))
/* See MS-SMB2 2.2.43 */
struct smb2_rdma_transform {
__le16 RdmaDescriptorOffset;
__le16 RdmaDescriptorLength;
__le32 Channel; /* for values see channel description in smb2 read above */
__le16 TransformCount;
__le16 Reserved1;
__le32 Reserved2;
} __packed;
/* TransformType */
#define SMB2_RDMA_TRANSFORM_TYPE_ENCRYPTION 0x0001
#define SMB2_RDMA_TRANSFORM_TYPE_SIGNING 0x0002
struct smb2_rdma_crypto_transform {
__le16 TransformType;
__le16 SignatureLength;
__le16 NonceLength;
__u16 Reserved;
__u8 Signature[]; /* variable length */
/* u8 Nonce[] */
/* followed by padding */
} __packed;
/*
* Definitions for SMB2 Protocol Data Units (network frames)
*
* See MS-SMB2.PDF specification for protocol details.
* The Naming convention is the lower case version of the SMB2
* command code name for the struct. Note that structures must be packed.
*
*/
#define COMPOUND_FID 0xFFFFFFFFFFFFFFFFULL
#define SMB2_SYMLINK_STRUCT_SIZE \
(sizeof(struct smb2_err_rsp) - 1 + sizeof(struct smb2_symlink_err_rsp))
#define SYMLINK_ERROR_TAG 0x4c4d5953
struct smb2_symlink_err_rsp {
__le32 SymLinkLength;
__le32 SymLinkErrorTag;
__le32 ReparseTag;
__le16 ReparseDataLength;
__le16 UnparsedPathLength;
__le16 SubstituteNameOffset;
__le16 SubstituteNameLength;
__le16 PrintNameOffset;
__le16 PrintNameLength;
__le32 Flags;
__u8 PathBuffer[];
} __packed;
/* SMB 3.1.1 and later dialects. See MS-SMB2 section 2.2.2.1 */
struct smb2_error_context_rsp {
__le32 ErrorDataLength;
__le32 ErrorId;
__u8 ErrorContextData; /* ErrorDataLength long array */
} __packed;
/* ErrorId values */
#define SMB2_ERROR_ID_DEFAULT 0x00000000
#define SMB2_ERROR_ID_SHARE_REDIRECT cpu_to_le32(0x72645253) /* "rdRS" */
/* Defines for Type field below (see MS-SMB2 2.2.2.2.2.1) */
#define MOVE_DST_IPADDR_V4 cpu_to_le32(0x00000001)
#define MOVE_DST_IPADDR_V6 cpu_to_le32(0x00000002)
struct move_dst_ipaddr {
__le32 Type;
__u32 Reserved;
__u8 address[16]; /* IPv4 followed by 12 bytes rsvd or IPv6 address */
} __packed;
struct share_redirect_error_context_rsp {
__le32 StructureSize;
__le32 NotificationType;
__le32 ResourceNameOffset;
__le32 ResourceNameLength;
__le16 Reserved;
__le16 TargetType;
__le32 IPAddrCount;
struct move_dst_ipaddr IpAddrMoveList[];
/* __u8 ResourceName[] */ /* Name of share as counted Unicode string */
} __packed;
/*
* Maximum number of iovs we need for an open/create request.
* [0] : struct smb2_create_req
* [1] : path
* [2] : lease context
* [3] : durable context
* [4] : posix context
* [5] : time warp context
* [6] : query id context
* [7] : compound padding
*/
#define SMB2_CREATE_IOV_SIZE 8
/*
* Maximum size of a SMB2_CREATE response is 64 (smb2 header) +
* 88 (fixed part of create response) + 520 (path) + 208 (contexts) +
* 2 bytes of padding.
*/
#define MAX_SMB2_CREATE_RESPONSE_SIZE 880
#define SMB2_LEASE_READ_CACHING_HE 0x01
#define SMB2_LEASE_HANDLE_CACHING_HE 0x02
#define SMB2_LEASE_WRITE_CACHING_HE 0x04
struct create_durable {
struct create_context ccontext;
__u8 Name[8];
union {
__u8 Reserved[16];
struct {
__u64 PersistentFileId;
__u64 VolatileFileId;
} Fid;
} Data;
} __packed;
/* See MS-SMB2 2.2.13.2.11 */
/* Flags */
#define SMB2_DHANDLE_FLAG_PERSISTENT 0x00000002
struct durable_context_v2 {
__le32 Timeout;
__le32 Flags;
__u64 Reserved;
__u8 CreateGuid[16];
} __packed;
struct create_durable_v2 {
struct create_context ccontext;
__u8 Name[8];
struct durable_context_v2 dcontext;
} __packed;
/* See MS-SMB2 2.2.13.2.12 */
struct durable_reconnect_context_v2 {
struct {
__u64 PersistentFileId;
__u64 VolatileFileId;
} Fid;
__u8 CreateGuid[16];
__le32 Flags; /* see above DHANDLE_FLAG_PERSISTENT */
} __packed;
/* See MS-SMB2 2.2.14.2.9 */
struct create_on_disk_id {
struct create_context ccontext;
__u8 Name[8];
__le64 DiskFileId;
__le64 VolumeId;
__u32 Reserved[4];
} __packed;
/* See MS-SMB2 2.2.14.2.12 */
struct durable_reconnect_context_v2_rsp {
__le32 Timeout;
__le32 Flags; /* see above DHANDLE_FLAG_PERSISTENT */
} __packed;
struct create_durable_handle_reconnect_v2 {
struct create_context ccontext;
__u8 Name[8];
struct durable_reconnect_context_v2 dcontext;
__u8 Pad[4];
} __packed;
/* See MS-SMB2 2.2.13.2.5 */
struct crt_twarp_ctxt {
struct create_context ccontext;
__u8 Name[8];
__le64 Timestamp;
} __packed;
/* See MS-SMB2 2.2.13.2.9 */
struct crt_query_id_ctxt {
struct create_context ccontext;
__u8 Name[8];
} __packed;
struct crt_sd_ctxt {
struct create_context ccontext;
__u8 Name[8];
struct smb3_sd sd;
} __packed;
#define COPY_CHUNK_RES_KEY_SIZE 24
struct resume_key_req {
char ResumeKey[COPY_CHUNK_RES_KEY_SIZE];
__le32 ContextLength; /* MBZ */
char Context[]; /* ignored, Windows sets to 4 bytes of zero */
} __packed;
/* this goes in the ioctl buffer when doing a copychunk request */
struct copychunk_ioctl {
char SourceKey[COPY_CHUNK_RES_KEY_SIZE];
__le32 ChunkCount; /* we are only sending 1 */
__le32 Reserved;
/* array will only be one chunk long for us */
__le64 SourceOffset;
__le64 TargetOffset;
__le32 Length; /* how many bytes to copy */
__u32 Reserved2;
} __packed;
struct copychunk_ioctl_rsp {
__le32 ChunksWritten;
__le32 ChunkBytesWritten;
__le32 TotalBytesWritten;
} __packed;
/* See MS-FSCC 2.3.29 and 2.3.30 */
struct get_retrieval_pointer_count_req {
__le64 StartingVcn; /* virtual cluster number (signed) */
} __packed;
struct get_retrieval_pointer_count_rsp {
__le32 ExtentCount;
} __packed;
/*
* See MS-FSCC 2.3.33 and 2.3.34
* request is the same as get_retrieval_point_count_req struct above
*/
struct smb3_extents {
__le64 NextVcn;
__le64 Lcn; /* logical cluster number */
} __packed;
struct get_retrieval_pointers_refcount_rsp {
__le32 ExtentCount;
__u32 Reserved;
__le64 StartingVcn;
struct smb3_extents extents[];
} __packed;
/* See MS-DFSC 2.2.2 */
struct fsctl_get_dfs_referral_req {
__le16 MaxReferralLevel;
__u8 RequestFileName[];
} __packed;
/* DFS response is struct get_dfs_refer_rsp */
/* See MS-SMB2 2.2.31.3 */
struct network_resiliency_req {
__le32 Timeout;
__le32 Reserved;
} __packed;
/* There is no buffer for the response ie no struct network_resiliency_rsp */
#define RSS_CAPABLE cpu_to_le32(0x00000001)
#define RDMA_CAPABLE cpu_to_le32(0x00000002)
#define INTERNETWORK cpu_to_le16(0x0002)
#define INTERNETWORKV6 cpu_to_le16(0x0017)
struct network_interface_info_ioctl_rsp {
__le32 Next; /* next interface. zero if this is last one */
__le32 IfIndex;
__le32 Capability; /* RSS or RDMA Capable */
__le32 Reserved;
__le64 LinkSpeed;
__le16 Family;
__u8 Buffer[126];
} __packed;
struct iface_info_ipv4 {
__be16 Port;
__be32 IPv4Address;
__be64 Reserved;
} __packed;
struct iface_info_ipv6 {
__be16 Port;
__be32 FlowInfo;
__u8 IPv6Address[16];
__be32 ScopeId;
} __packed;
#define NO_FILE_ID 0xFFFFFFFFFFFFFFFFULL /* general ioctls to srv not to file */
struct compress_ioctl {
__le16 CompressionState; /* See cifspdu.h for possible flag values */
} __packed;
/*
* Maximum number of iovs we need for an ioctl request.
* [0] : struct smb2_ioctl_req
* [1] : in_data
*/
#define SMB2_IOCTL_IOV_SIZE 2
/*
* PDU query infolevel structure definitions
* BB consider moving to a different header
*/
struct smb2_file_full_ea_info { /* encoding of response for level 15 */
__le32 next_entry_offset;
__u8 flags;
__u8 ea_name_length;
__le16 ea_value_length;
char ea_data[]; /* \0 terminated name plus value */
} __packed; /* level 15 Set */
struct smb2_file_reparse_point_info {
__le64 IndexNumber;
__le32 Tag;
} __packed;
struct smb2_file_network_open_info {
__le64 CreationTime;
__le64 LastAccessTime;
__le64 LastWriteTime;
__le64 ChangeTime;
__le64 AllocationSize;
__le64 EndOfFile;
__le32 Attributes;
__le32 Reserved;
} __packed; /* level 34 Query also similar returned in close rsp and open rsp */
/* See MS-FSCC 2.4.21 */
struct smb2_file_id_information {
__le64 VolumeSerialNumber;
__u64 PersistentFileId; /* opaque endianness */
__u64 VolatileFileId; /* opaque endianness */
} __packed; /* level 59 */
/* See MS-FSCC 2.4.18 */
struct smb2_file_id_extd_directory_info {
__le32 NextEntryOffset;
__u32 FileIndex;
__le64 CreationTime;
__le64 LastAccessTime;
__le64 LastWriteTime;
__le64 ChangeTime;
__le64 EndOfFile;
__le64 AllocationSize;
__le32 FileAttributes;
__le32 FileNameLength;
__le32 EaSize; /* EA size */
__le32 ReparsePointTag; /* valid if FILE_ATTR_REPARSE_POINT set in FileAttributes */
__le64 UniqueId; /* inode num - le since Samba puts ino in low 32 bit */
char FileName[1];
} __packed; /* level 60 */
extern char smb2_padding[7];
/* equivalent of the contents of SMB3.1.1 POSIX open context response */
struct create_posix_rsp {
u32 nlink;
u32 reparse_tag;
u32 mode;
struct cifs_sid owner; /* var-sized on the wire */
struct cifs_sid group; /* var-sized on the wire */
} __packed;
#define SMB2_QUERY_DIRECTORY_IOV_SIZE 2
/*
* SMB2-only POSIX info level for query dir
*
* See posix_info_sid_size(), posix_info_extra_size() and
* posix_info_parse() to help with the handling of this struct.
*/
struct smb2_posix_info {
__le32 NextEntryOffset;
__u32 Ignored;
__le64 CreationTime;
__le64 LastAccessTime;
__le64 LastWriteTime;
__le64 ChangeTime;
__le64 EndOfFile;
__le64 AllocationSize;
__le32 DosAttributes;
__le64 Inode;
__le32 DeviceId;
__le32 Zero;
/* beginning of POSIX Create Context Response */
__le32 HardLinks;
__le32 ReparseTag;
__le32 Mode;
/*
* var sized owner SID
* var sized group SID
* le32 filenamelength
* u8 filename[]
*/
} __packed;
/*
* Parsed version of the above struct. Allows direct access to the
* variable length fields
*/
struct smb2_posix_info_parsed {
const struct smb2_posix_info *base;
size_t size;
struct cifs_sid owner;
struct cifs_sid group;
int name_len;
const u8 *name;
};
#endif /* _SMB2PDU_H */