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