1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only
2 config CIFS 2 config CIFS
3 tristate "SMB3 and CIFS support (advan 3 tristate "SMB3 and CIFS support (advanced network filesystem)"
4 depends on INET 4 depends on INET
5 select NETFS_SUPPORT <<
6 select NLS 5 select NLS
7 select NLS_UCS2_UTILS 6 select NLS_UCS2_UTILS
8 select CRYPTO 7 select CRYPTO
9 select CRYPTO_MD5 8 select CRYPTO_MD5
10 select CRYPTO_SHA256 9 select CRYPTO_SHA256
11 select CRYPTO_SHA512 10 select CRYPTO_SHA512
12 select CRYPTO_CMAC 11 select CRYPTO_CMAC
13 select CRYPTO_HMAC 12 select CRYPTO_HMAC
14 select CRYPTO_AEAD2 13 select CRYPTO_AEAD2
15 select CRYPTO_CCM 14 select CRYPTO_CCM
16 select CRYPTO_GCM 15 select CRYPTO_GCM
17 select CRYPTO_ECB 16 select CRYPTO_ECB
18 select CRYPTO_AES 17 select CRYPTO_AES
19 select KEYS 18 select KEYS
20 select DNS_RESOLVER 19 select DNS_RESOLVER
21 select ASN1 20 select ASN1
22 select OID_REGISTRY 21 select OID_REGISTRY
23 select NETFS_SUPPORT 22 select NETFS_SUPPORT
24 help 23 help
25 This is the client VFS module for th 24 This is the client VFS module for the SMB3 family of network file
26 protocols (including the most recent 25 protocols (including the most recent, most secure dialect SMB3.1.1).
27 This module also includes support fo 26 This module also includes support for earlier dialects such as
28 SMB2.1, SMB2 and even the old Common 27 SMB2.1, SMB2 and even the old Common Internet File System (CIFS)
29 protocol. CIFS was the successor to 28 protocol. CIFS was the successor to the original network filesystem
30 protocol, Server Message Block (SMB 29 protocol, Server Message Block (SMB ie SMB1), the native file sharing
31 mechanism for most early PC operatin 30 mechanism for most early PC operating systems.
32 31
33 The SMB3.1.1 protocol is supported b 32 The SMB3.1.1 protocol is supported by most modern operating systems
34 and NAS appliances (e.g. Samba, Wind 33 and NAS appliances (e.g. Samba, Windows 11, Windows Server 2022,
35 MacOS) and even in the cloud (e.g. M 34 MacOS) and even in the cloud (e.g. Microsoft Azure) and also by the
36 Linux kernel server, ksmbd. Support 35 Linux kernel server, ksmbd. Support for the older CIFS protocol was
37 included in Windows NT4, 2000 and XP 36 included in Windows NT4, 2000 and XP (and later). Use of dialects
38 older than SMB2.1 is often discourag 37 older than SMB2.1 is often discouraged on public networks.
39 This module also provides limited su 38 This module also provides limited support for OS/2 and Windows ME
40 and similar very old servers. 39 and similar very old servers.
41 40
42 This module provides an advanced net 41 This module provides an advanced network file system client for
43 mounting to SMB3 (and CIFS) complian 42 mounting to SMB3 (and CIFS) compliant servers. It includes support
44 for DFS (hierarchical name space), s 43 for DFS (hierarchical name space), secure per-user session
45 establishment via Kerberos or NTLMv2 44 establishment via Kerberos or NTLMv2, RDMA (smbdirect), advanced
46 security features, per-share encrypt 45 security features, per-share encryption, packet-signing, snapshots,
47 directory leases, safe distributed c 46 directory leases, safe distributed caching (leases), multichannel,
48 Unicode and other internationalizati 47 Unicode and other internationalization improvements.
49 48
50 In general, the default dialects, SM 49 In general, the default dialects, SMB3 and later, enable better
51 performance, security and features, 50 performance, security and features, than would be possible with CIFS.
52 51
53 If you need to mount to Samba, Azure 52 If you need to mount to Samba, Azure, ksmbd, Macs or Windows from this
54 machine, say Y. 53 machine, say Y.
55 54
56 config CIFS_STATS2 55 config CIFS_STATS2
57 bool "Extended statistics" 56 bool "Extended statistics"
58 depends on CIFS 57 depends on CIFS
59 default y 58 default y
60 help 59 help
61 Enabling this option will allow more 60 Enabling this option will allow more detailed statistics on SMB
62 request timing to be displayed in /p 61 request timing to be displayed in /proc/fs/cifs/DebugData and also
63 allow optional logging of slow respo 62 allow optional logging of slow responses to dmesg (depending on the
64 value of /proc/fs/cifs/cifsFYI). See 63 value of /proc/fs/cifs/cifsFYI). See Documentation/admin-guide/cifs/usage.rst
65 for more details. These additional s 64 for more details. These additional statistics may have a minor effect
66 on performance and memory utilizatio 65 on performance and memory utilization.
67 66
68 If unsure, say Y. 67 If unsure, say Y.
69 68
70 config CIFS_ALLOW_INSECURE_LEGACY 69 config CIFS_ALLOW_INSECURE_LEGACY
71 bool "Support legacy servers which use 70 bool "Support legacy servers which use less secure dialects"
72 depends on CIFS 71 depends on CIFS
73 default y 72 default y
74 help 73 help
75 Modern dialects, SMB2.1 and later (i 74 Modern dialects, SMB2.1 and later (including SMB3 and 3.1.1), have
76 additional security features, includ 75 additional security features, including protection against
77 man-in-the-middle attacks and strong 76 man-in-the-middle attacks and stronger crypto hashes, so the use
78 of legacy dialects (SMB1/CIFS and SM 77 of legacy dialects (SMB1/CIFS and SMB2.0) is discouraged.
79 78
80 Disabling this option prevents users 79 Disabling this option prevents users from using vers=1.0 or vers=2.0
81 on mounts with cifs.ko 80 on mounts with cifs.ko
82 81
83 If unsure, say Y. 82 If unsure, say Y.
84 83
85 config CIFS_UPCALL 84 config CIFS_UPCALL
86 bool "Kerberos/SPNEGO advanced session 85 bool "Kerberos/SPNEGO advanced session setup"
87 depends on CIFS 86 depends on CIFS
88 help 87 help
89 Enables an upcall mechanism for CIFS 88 Enables an upcall mechanism for CIFS which accesses userspace helper
90 utilities to provide SPNEGO packaged 89 utilities to provide SPNEGO packaged (RFC 4178) Kerberos tickets
91 which are needed to mount to certain 90 which are needed to mount to certain secure servers (for which more
92 secure Kerberos authentication is re 91 secure Kerberos authentication is required). If unsure, say Y.
93 92
94 config CIFS_XATTR 93 config CIFS_XATTR
95 bool "CIFS extended attributes" 94 bool "CIFS extended attributes"
96 depends on CIFS 95 depends on CIFS
97 help 96 help
98 Extended attributes are name:value p 97 Extended attributes are name:value pairs associated with inodes by
99 the kernel or by users (see the attr 98 the kernel or by users (see the attr(5) manual page for details).
100 CIFS maps the name of extended attri 99 CIFS maps the name of extended attributes beginning with the user
101 namespace prefix to SMB/CIFS EAs. E 100 namespace prefix to SMB/CIFS EAs. EAs are stored on Windows
102 servers without the user namespace p 101 servers without the user namespace prefix, but their names are
103 seen by Linux cifs clients prefaced 102 seen by Linux cifs clients prefaced by the user namespace prefix.
104 The system namespace (used by some f 103 The system namespace (used by some filesystems to store ACLs) is
105 not supported at this time. 104 not supported at this time.
106 105
107 If unsure, say Y. 106 If unsure, say Y.
108 107
109 config CIFS_POSIX 108 config CIFS_POSIX
110 bool "CIFS POSIX Extensions" 109 bool "CIFS POSIX Extensions"
111 depends on CIFS && CIFS_ALLOW_INSECURE 110 depends on CIFS && CIFS_ALLOW_INSECURE_LEGACY && CIFS_XATTR
112 help 111 help
113 Enabling this option will cause the 112 Enabling this option will cause the cifs client to attempt to
114 negotiate a feature of the older cif 113 negotiate a feature of the older cifs dialect with servers, such as
115 Samba 3.0.5 or later, that optionall 114 Samba 3.0.5 or later, that optionally can handle more POSIX like
116 (rather than Windows like) file beha 115 (rather than Windows like) file behavior. It also enables support
117 for POSIX ACLs (getfacl and setfacl) 116 for POSIX ACLs (getfacl and setfacl) to servers (such as Samba 3.10
118 and later) which can negotiate CIFS 117 and later) which can negotiate CIFS POSIX ACL support. This config
119 option is not needed when mounting w 118 option is not needed when mounting with SMB3.1.1. If unsure, say N.
120 119
121 config CIFS_DEBUG 120 config CIFS_DEBUG
122 bool "Enable CIFS debugging routines" 121 bool "Enable CIFS debugging routines"
123 default y 122 default y
124 depends on CIFS 123 depends on CIFS
125 help 124 help
126 Enabling this option adds helpful de 125 Enabling this option adds helpful debugging messages to
127 the cifs code which increases the si 126 the cifs code which increases the size of the cifs module.
128 If unsure, say Y. 127 If unsure, say Y.
129 128
130 config CIFS_DEBUG2 129 config CIFS_DEBUG2
131 bool "Enable additional CIFS debugging 130 bool "Enable additional CIFS debugging routines"
132 depends on CIFS_DEBUG 131 depends on CIFS_DEBUG
133 help 132 help
134 Enabling this option adds a few more 133 Enabling this option adds a few more debugging routines
135 to the cifs code which slightly incr 134 to the cifs code which slightly increases the size of
136 the cifs module and can cause additi 135 the cifs module and can cause additional logging of debug
137 messages in some error paths, slowin 136 messages in some error paths, slowing performance. This
138 option can be turned off unless you 137 option can be turned off unless you are debugging
139 cifs problems. If unsure, say N. 138 cifs problems. If unsure, say N.
140 139
141 config CIFS_DEBUG_DUMP_KEYS 140 config CIFS_DEBUG_DUMP_KEYS
142 bool "Dump encryption keys for offline 141 bool "Dump encryption keys for offline decryption (Unsafe)"
143 depends on CIFS_DEBUG 142 depends on CIFS_DEBUG
144 help 143 help
145 Enabling this will dump the encrypti 144 Enabling this will dump the encryption and decryption keys
146 used to communicate on an encrypted 145 used to communicate on an encrypted share connection on the
147 console. This allows Wireshark to de 146 console. This allows Wireshark to decrypt and dissect
148 encrypted network captures. Enable t 147 encrypted network captures. Enable this carefully.
149 If unsure, say N. 148 If unsure, say N.
150 149
151 config CIFS_DFS_UPCALL 150 config CIFS_DFS_UPCALL
152 bool "DFS feature support" 151 bool "DFS feature support"
153 depends on CIFS 152 depends on CIFS
154 help 153 help
155 Distributed File System (DFS) suppor 154 Distributed File System (DFS) support is used to access shares
156 transparently in an enterprise name 155 transparently in an enterprise name space, even if the share
157 moves to a different server. This f 156 moves to a different server. This feature also enables
158 an upcall mechanism for CIFS which c 157 an upcall mechanism for CIFS which contacts userspace helper
159 utilities to provide server name res 158 utilities to provide server name resolution (host names to
160 IP addresses) which is needed in ord 159 IP addresses) which is needed in order to reconnect to
161 servers if their addresses change or 160 servers if their addresses change or for implicit mounts of
162 DFS junction points. If unsure, say 161 DFS junction points. If unsure, say Y.
163 162
164 config CIFS_SWN_UPCALL 163 config CIFS_SWN_UPCALL
165 bool "SWN feature support" 164 bool "SWN feature support"
166 depends on CIFS 165 depends on CIFS
167 help 166 help
168 The Service Witness Protocol (SWN) i 167 The Service Witness Protocol (SWN) is used to get notifications
169 from a highly available server of re 168 from a highly available server of resource state changes. This
170 feature enables an upcall mechanism 169 feature enables an upcall mechanism for CIFS which contacts a
171 userspace daemon to establish the DC 170 userspace daemon to establish the DCE/RPC connection to retrieve
172 the cluster available interfaces and 171 the cluster available interfaces and resource change notifications.
173 If unsure, say Y. 172 If unsure, say Y.
174 173
175 config CIFS_NFSD_EXPORT 174 config CIFS_NFSD_EXPORT
176 bool "Allow nfsd to export CIFS file s 175 bool "Allow nfsd to export CIFS file system"
177 depends on CIFS && BROKEN 176 depends on CIFS && BROKEN
178 help 177 help
179 Allows NFS server to export a CIFS m 178 Allows NFS server to export a CIFS mounted share (nfsd over cifs)
180 179
181 if CIFS 180 if CIFS
182 181
183 config CIFS_SMB_DIRECT 182 config CIFS_SMB_DIRECT
184 bool "SMB Direct support" 183 bool "SMB Direct support"
185 depends on CIFS=m && INFINIBAND && INF 184 depends on CIFS=m && INFINIBAND && INFINIBAND_ADDR_TRANS || CIFS=y && INFINIBAND=y && INFINIBAND_ADDR_TRANS=y
186 help 185 help
187 Enables SMB Direct support for SMB 3 186 Enables SMB Direct support for SMB 3.0, 3.02 and 3.1.1.
188 SMB Direct allows transferring SMB p 187 SMB Direct allows transferring SMB packets over RDMA. If unsure,
189 say Y. 188 say Y.
190 189
191 config CIFS_FSCACHE 190 config CIFS_FSCACHE
192 bool "Provide CIFS client caching supp 191 bool "Provide CIFS client caching support"
193 depends on CIFS=m && FSCACHE || CIFS=y 192 depends on CIFS=m && FSCACHE || CIFS=y && FSCACHE=y
194 help 193 help
195 Makes CIFS FS-Cache capable. Say Y h 194 Makes CIFS FS-Cache capable. Say Y here if you want your CIFS data
196 to be cached locally on disk through 195 to be cached locally on disk through the general filesystem cache
197 manager. If unsure, say N. 196 manager. If unsure, say N.
198 197
199 config CIFS_ROOT 198 config CIFS_ROOT
200 bool "SMB root file system (Experiment 199 bool "SMB root file system (Experimental)"
201 depends on CIFS=y && IP_PNP 200 depends on CIFS=y && IP_PNP
202 help 201 help
203 Enables root file system support ove 202 Enables root file system support over SMB protocol.
204 203
205 Most people say N here. 204 Most people say N here.
206 <<
207 config CIFS_COMPRESSION <<
208 bool "SMB message compression (Experim <<
209 depends on CIFS <<
210 default n <<
211 help <<
212 Enables over-the-wire message compre <<
213 mounts when negotiated with the serv <<
214 <<
215 Only write requests with data size > <<
216 compressed to avoid wasting resource <<
217 <<
218 Say Y here if you want SMB traffic t <<
219 If unsure, say N. <<
220 205
221 endif 206 endif
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