NAME

       client.conf - client configuration file for cups (deprecated on macos)

DESCRIPTION

       The  client.conf  file configures the CUPS client and is normally located in the /etc/cups and/or ~/.cups
       directories.  Each line in the file can be a configuration directive, a blank line, or a comment. Comment
       lines start with the # character.

       Note: Starting with macOS 10.7, this file is only used by command-line and X11 applications plus the  IPP
       backend.   The  ServerName  directive  is  not supported on macOS at all.  Starting with macOS 10.12, all
       applications can access these  settings  in  the  /Library/Preferences/org.cups.PrintingPrefs.plist  file
       instead.  See the NOTES section below for more information.

   DIRECTIVES
       The following directives are understood by the client. Consult the online help for detailed descriptions:

       AllowAnyRoot Yes

       AllowAnyRoot No
            Specifies  whether to allow TLS with certificates that have not been signed by a trusted Certificate
            Authority.  The default is "Yes".

       AllowExpiredCerts Yes

       AllowExpiredCerts No
            Specifies whether to allow TLS with expired certificates.  The default is "No".

       DigestOptions DenyMD5

       DigestOptions None
            Specifies HTTP Digest authentication options.  DenyMD5 disables support for the  original  MD5  hash
            algorithm.

       Encryption IfRequested

       Encryption Never

       Encryption Required
            Specifies the level of encryption that should be used.

       GSSServiceName name
            Specifies  the  Kerberos  service name that is used for authentication, typically "host", "http", or
            "ipp".  CUPS adds the remote hostname ("name@server.example.com")  for  you.  The  default  name  is
            "http".

       ServerName hostname-or-ip-address[:port]

       ServerName /domain/socket
            Specifies  the  address  and  optionally  the port to use when connecting to the server.  Note: This
            directive is not supported on macOS 10.7 or later.

       ServerName hostname-or-ip-address[:port]/version=1.1
            Specifies the address and optionally the port to use when connecting to a server running CUPS 1.3.12
            and earlier.

       SSLOptions [AllowDH] [AllowRC4] [AllowSSL3] [DenyCBC] [DenyTLS1.0] [MaxTLS1.0] [MaxTLS1.1] [MaxTLS1.2]
       [MaxTLS1.3] [MinTLS1.0] [MinTLS1.1] [MinTLS1.2] [MinTLS1.3]

       SSLOptions None
            Sets encryption options (only in /etc/cups/client.conf).  By default, CUPS only supports  encryption
            using  TLS  v1.0 or higher using known secure cipher suites.  Security is reduced when Allow options
            are used.  Security is enhanced when Deny options are  used.   The  AllowDH  option  enables  cipher
            suites  using  plain  Diffie-Hellman  key negotiation (not supported on systems using GNU TLS).  The
            AllowRC4 option enables the 128-bit RC4 cipher suites, which are required for  some  older  clients.
            The  AllowSSL3 option enables SSL v3.0, which is required for some older clients that do not support
            TLS v1.0.  The DenyCBC option disables all CBC cipher suites.  The DenyTLS1.0  option  disables  TLS
            v1.0  support  -  this  sets  the  minimum protocol version to TLS v1.1.  The MinTLS options set the
            minimum TLS version to support.  The MaxTLS options set the maximum TLS version to support.  Not all
            operating systems support TLS 1.3 at this time.

       TrustOnFirstUse Yes

       TrustOnFirstUse No
            Specifies whether to trust new TLS certificates by default.  The default is "Yes".

       User name
            Specifies the default user name to use for requests.

       UserAgentTokens None

       UserAgentTokens ProductOnly

       UserAgentTokens Major

       UserAgentTokens Minor

       UserAgentTokens Minimal

       UserAgentTokens OS

       UserAgentTokens Full
            Specifies what information is included in the User-Agent header of HTTP requests.   "None"  disables
            the  User-Agent header.  "ProductOnly" reports "CUPS".  "Major" reports "CUPS/major IPP/2".  "Minor"
            reports "CUPS/major.minor  IPP/2.1".   "Minimal"  reports  "CUPS/major.minor.patch  IPP/2.1".   "OS"
            reports  "CUPS/major.minor.path  (osname osversion) IPP/2.1".  "Full" reports "CUPS/major.minor.path
            (osname osversion; architecture) IPP/2.1".  The default is "Minimal".

       ValidateCerts Yes

       ValidateCerts No
            Specifies whether to only allow TLS with certificates whose common name matches the  hostname.   The
            default is "No".

NOTES

       The  client.conf file is deprecated on macOS and will no longer be supported in a future version of CUPS.
       Configuration settings can instead be viewed or changed using the defaults(1) command:
       defaults write /Library/Preferences/org.cups.PrintingPrefs.plist Encryption Required
       defaults write /Library/Preferences/org.cups.PrintingPrefs.plist TrustOnFirstUse -bool NO

       defaults read /Library/Preferences/org.cups.PrintingPrefs.plist Encryption
       On Linux and other systems using GNU TLS, the /etc/cups/ssl/site.crl file, if present, provides a list of
       revoked X.509 certificates and is used when validating certificates.

SEE ALSO

       cups(1), default(1), CUPS Online Help (http://localhost:631/help)

COPYRIGHT

       Copyright © 2021-2023 by OpenPrinting.

2021-02-28                                            CUPS                                        client.conf(5)