From 95907fea4fd8ccc736e0a428e52159b4d42b9958 Mon Sep 17 00:00:00 2001 From: Ronnie Sahlberg Date: Thu, 24 Aug 2017 11:24:55 +1000 Subject: [PATCH] cifs: Add support for reading attributes on SMB2+ SMB1 already has support to read attributes. This adds similar support to SMB2+. With this patch, tools such as 'getfattr' will now work with SMB2+ shares. RH-bz: 1110709 Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/smb2ops.c | 144 ++++++++++++++++++++++++++++++++++++++++++++ fs/cifs/smb2pdu.c | 12 ++++ fs/cifs/smb2pdu.h | 10 +++ fs/cifs/smb2proto.h | 3 + 4 files changed, 169 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index cfacf2c97e94..78516d3a133c 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -426,6 +426,138 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon, return rc; } +static ssize_t +move_smb2_ea_to_cifs(char *dst, size_t dst_size, + struct smb2_file_full_ea_info *src, size_t src_size, + const unsigned char *ea_name) +{ + int rc = 0; + unsigned int ea_name_len = ea_name ? strlen(ea_name) : 0; + char *name, *value; + size_t name_len, value_len, user_name_len; + + while (src_size > 0) { + name = &src->ea_data[0]; + name_len = (size_t)src->ea_name_length; + value = &src->ea_data[src->ea_name_length + 1]; + value_len = (size_t)le16_to_cpu(src->ea_value_length); + + if (name_len == 0) { + break; + } + + if (src_size < 8 + name_len + 1 + value_len) { + cifs_dbg(FYI, "EA entry goes beyond length of list\n"); + rc = -EIO; + goto out; + } + + if (ea_name) { + if (ea_name_len == name_len && + memcmp(ea_name, name, name_len) == 0) { + rc = value_len; + if (dst_size == 0) + goto out; + if (dst_size < value_len) { + rc = -ERANGE; + goto out; + } + memcpy(dst, value, value_len); + goto out; + } + } else { + /* 'user.' plus a terminating null */ + user_name_len = 5 + 1 + name_len; + + rc += user_name_len; + + if (dst_size >= user_name_len) { + dst_size -= user_name_len; + memcpy(dst, "user.", 5); + dst += 5; + memcpy(dst, src->ea_data, name_len); + dst += name_len; + *dst = 0; + ++dst; + } else if (dst_size == 0) { + /* skip copy - calc size only */ + } else { + /* stop before overrun buffer */ + rc = -ERANGE; + break; + } + } + + if (!src->next_entry_offset) + break; + + if (src_size < le32_to_cpu(src->next_entry_offset)) { + /* stop before overrun buffer */ + rc = -ERANGE; + break; + } + src_size -= le32_to_cpu(src->next_entry_offset); + src = (void *)((char *)src + + le32_to_cpu(src->next_entry_offset)); + } + + /* didn't find the named attribute */ + if (ea_name) + rc = -ENODATA; + +out: + return (ssize_t)rc; +} + +static ssize_t +smb2_query_eas(const unsigned int xid, struct cifs_tcon *tcon, + const unsigned char *path, const unsigned char *ea_name, + char *ea_data, size_t buf_size, + struct cifs_sb_info *cifs_sb) +{ + int rc; + __le16 *utf16_path; + __u8 oplock = SMB2_OPLOCK_LEVEL_NONE; + struct cifs_open_parms oparms; + struct cifs_fid fid; + struct smb2_file_full_ea_info *smb2_data; + + utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); + if (!utf16_path) + return -ENOMEM; + + oparms.tcon = tcon; + oparms.desired_access = FILE_READ_EA; + oparms.disposition = FILE_OPEN; + oparms.create_options = 0; + oparms.fid = &fid; + oparms.reconnect = false; + + rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL); + kfree(utf16_path); + if (rc) { + cifs_dbg(FYI, "open failed rc=%d\n", rc); + return rc; + } + + smb2_data = kzalloc(SMB2_MAX_EA_BUF, GFP_KERNEL); + if (smb2_data == NULL) { + SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); + return -ENOMEM; + } + + rc = SMB2_query_eas(xid, tcon, fid.persistent_fid, fid.volatile_fid, + smb2_data); + SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); + + if (!rc) + rc = move_smb2_ea_to_cifs(ea_data, buf_size, smb2_data, + SMB2_MAX_EA_BUF, ea_name); + + kfree(smb2_data); + return rc; +} + static bool smb2_can_echo(struct TCP_Server_Info *server) { @@ -2572,6 +2704,9 @@ struct smb_version_operations smb20_operations = { .dir_needs_close = smb2_dir_needs_close, .get_dfs_refer = smb2_get_dfs_refer, .select_sectype = smb2_select_sectype, +#ifdef CONFIG_CIFS_XATTR + .query_all_EAs = smb2_query_eas, +#endif /* CIFS_XATTR */ #ifdef CONFIG_CIFS_ACL .get_acl = get_smb2_acl, .get_acl_by_fid = get_smb2_acl_by_fid, @@ -2662,6 +2797,9 @@ struct smb_version_operations smb21_operations = { .enum_snapshots = smb3_enum_snapshots, .get_dfs_refer = smb2_get_dfs_refer, .select_sectype = smb2_select_sectype, +#ifdef CONFIG_CIFS_XATTR + .query_all_EAs = smb2_query_eas, +#endif /* CIFS_XATTR */ #ifdef CONFIG_CIFS_ACL .get_acl = get_smb2_acl, .get_acl_by_fid = get_smb2_acl_by_fid, @@ -2762,6 +2900,9 @@ struct smb_version_operations smb30_operations = { .receive_transform = smb3_receive_transform, .get_dfs_refer = smb2_get_dfs_refer, .select_sectype = smb2_select_sectype, +#ifdef CONFIG_CIFS_XATTR + .query_all_EAs = smb2_query_eas, +#endif /* CIFS_XATTR */ #ifdef CONFIG_CIFS_ACL .get_acl = get_smb2_acl, .get_acl_by_fid = get_smb2_acl_by_fid, @@ -2863,6 +3004,9 @@ struct smb_version_operations smb311_operations = { .receive_transform = smb3_receive_transform, .get_dfs_refer = smb2_get_dfs_refer, .select_sectype = smb2_select_sectype, +#ifdef CONFIG_CIFS_XATTR + .query_all_EAs = smb2_query_eas, +#endif /* CIFS_XATTR */ }; #endif /* CIFS_SMB311 */ diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 7aa67206f6da..bf0ba3c15b63 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -2145,6 +2145,18 @@ qinf_exit: return rc; } +int SMB2_query_eas(const unsigned int xid, struct cifs_tcon *tcon, + u64 persistent_fid, u64 volatile_fid, + struct smb2_file_full_ea_info *data) +{ + return query_info(xid, tcon, persistent_fid, volatile_fid, + FILE_FULL_EA_INFORMATION, SMB2_O_INFO_FILE, 0, + SMB2_MAX_EA_BUF, + sizeof(struct smb2_file_full_ea_info), + (void **)&data, + NULL); +} + int SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_fid, u64 volatile_fid, struct smb2_file_all_info *data) { diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h index 2826882c81d1..393ed5f4e1b6 100644 --- a/fs/cifs/smb2pdu.h +++ b/fs/cifs/smb2pdu.h @@ -1178,6 +1178,16 @@ struct smb2_file_link_info { /* encoding of request for level 11 */ char FileName[0]; /* Name to be assigned to new link */ } __packed; /* level 11 Set */ +#define SMB2_MAX_EA_BUF 2048 + +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]; /* \0 terminated name plus value */ +} __packed; /* level 15 Set */ + /* * This level 18, although with struct with same name is different from cifs * level 0x107. Level 0x107 has an extra u64 between AccessFlags and diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h index 1cadaf9f3c58..183389bfc8f6 100644 --- a/fs/cifs/smb2proto.h +++ b/fs/cifs/smb2proto.h @@ -132,6 +132,9 @@ extern int SMB2_close(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_file_id, u64 volatile_file_id); extern int SMB2_flush(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_file_id, u64 volatile_file_id); +extern int SMB2_query_eas(const unsigned int xid, struct cifs_tcon *tcon, + u64 persistent_file_id, u64 volatile_file_id, + struct smb2_file_full_ea_info *data); extern int SMB2_query_info(const unsigned int xid, struct cifs_tcon *tcon, u64 persistent_file_id, u64 volatile_file_id, struct smb2_file_all_info *data); -- 2.20.1