1client.conf(5) OpenPrinting client.conf(5)
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6 client.conf - client configuration file for cups (deprecated on macos)
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9 The client.conf file configures the CUPS client and is normally located
10 in the /etc/cups and/or ~/.cups directories. Each line in the file can
11 be a configuration directive, a blank line, or a comment. Comment lines
12 start with the # character.
13 Note: Starting with macOS 10.7, this file is only used by command-line
15 and X11 applications plus the IPP backend. The ServerName directive is
16 not supported on macOS at all. Starting with macOS 10.12, all applica‐
17 tions can access these settings in the /Library/Prefer‐
18 ences/org.cups.PrintingPrefs.plist file instead. See the NOTES section
19 below for more information.
20 DIRECTIVES
22 The following directives are understood by the client. Consult the on‐
23 line help for detailed descriptions:
24 AllowAnyRoot Yes
26 AllowAnyRoot No
28 Specifies whether to allow TLS with certificates that have not
29 been signed by a trusted Certificate Authority. The default is
30 "Yes".
31 AllowExpiredCerts Yes
33 AllowExpiredCerts No
35 Specifies whether to allow TLS with expired certificates. The de‐
36 fault is "No".
37 DigestOptions DenyMD5
39 DigestOptions None
41 Specifies HTTP Digest authentication options. DenyMD5 disables
42 support for the original MD5 hash algorithm.
43 Encryption IfRequested
45 Encryption Never
47 Encryption Required
49 Specifies the level of encryption that should be used.
50 GSSServiceName name
52 Specifies the Kerberos service name that is used for authentica‐
53 tion, typically "host", "http", or "ipp". CUPS adds the remote
54 hostname ("name@server.example.com") for you. The default name is
55 "http".
56 ServerName hostname-or-ip-address[:port]
58 ServerName /domain/socket
60 Specifies the address and optionally the port to use when connect‐
61 ing to the server. Note: This directive is not supported on macOS
62 10.7 or later.
63 ServerName hostname-or-ip-address[:port]/version=1.1
65 Specifies the address and optionally the port to use when connect‐
66 ing to a server running CUPS 1.3.12 and earlier.
67 SSLOptions [AllowDH] [AllowRC4] [AllowSSL3] [DenyCBC] [DenyTLS1.0]
69 [MaxTLS1.0] [MaxTLS1.1] [MaxTLS1.2] [MaxTLS1.3] [MinTLS1.0] [MinTLS1.1]
70 [MinTLS1.2] [MinTLS1.3]
71 SSLOptions None
73 Sets encryption options (only in /etc/cups/client.conf). By de‐
74 fault, CUPS only supports encryption using TLS v1.0 or higher us‐
75 ing known secure cipher suites. Security is reduced when Allow
76 options are used. Security is enhanced when Deny options are
77 used. The AllowDH option enables cipher suites using plain
78 Diffie-Hellman key negotiation (not supported on systems using GNU
79 TLS). The AllowRC4 option enables the 128-bit RC4 cipher suites,
80 which are required for some older clients. The AllowSSL3 option
81 enables SSL v3.0, which is required for some older clients that do
82 not support TLS v1.0. The DenyCBC option disables all CBC cipher
83 suites. The DenyTLS1.0 option disables TLS v1.0 support - this
84 sets the minimum protocol version to TLS v1.1. The MinTLS options
85 set the minimum TLS version to support. The MaxTLS options set
86 the maximum TLS version to support. Not all operating systems
87 support TLS 1.3 at this time.
88 TrustOnFirstUse Yes
90 TrustOnFirstUse No
92 Specifies whether to trust new TLS certificates by default. The
93 default is "Yes".
94 User name
96 Specifies the default user name to use for requests.
97 UserAgentTokens None
99 UserAgentTokens ProductOnly
101 UserAgentTokens Major
103 UserAgentTokens Minor
105 UserAgentTokens Minimal
107 UserAgentTokens OS
109 UserAgentTokens Full
111 Specifies what information is included in the User-Agent header of
112 HTTP requests. "None" disables the User-Agent header. "Produc‐
113 tOnly" reports "CUPS". "Major" reports "CUPS/major IPP/2". "Mi‐
114 nor" reports "CUPS/major.minor IPP/2.1". "Minimal" reports
115 "CUPS/major.minor.patch IPP/2.1". "OS" reports "CUPS/major.mi‐
116 nor.path (osname osversion) IPP/2.1". "Full" reports "CUPS/ma‐
117 jor.minor.path (osname osversion; architecture) IPP/2.1". The de‐
118 fault is "Minimal".
119 ValidateCerts Yes
121 ValidateCerts No
123 Specifies whether to only allow TLS with certificates whose common
124 name matches the hostname. The default is "No".
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127 The client.conf file is deprecated on macOS and will no longer be sup‐
128 ported in a future version of CUPS. Configuration settings can instead
129 be viewed or changed using the defaults(1) command:
130 defaults write /Library/Preferences/org.cups.PrintingPrefs.plist Encryption Required
131 defaults write /Library/Preferences/org.cups.PrintingPrefs.plist TrustOnFirstUse -bool NO
132 defaults read /Library/Preferences/org.cups.PrintingPrefs.plist Encryption
134 On Linux and other systems using GNU TLS, the /etc/cups/ssl/site.crl
135 file, if present, provides a list of revoked X.509 certificates and is
136 used when validating certificates.
137
139 cups(1), default(1), CUPS Online Help (http://localhost:631/help)
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142 Copyright © 2021-2022 by OpenPrinting.
1432021-02-28 CUPS client.conf(5)