Provided by: ipp-usb_0.9.23-1_amd64 bug

NAME

       ipp-usb - Daemon for IPP over USB printer support

DESCRIPTION

       ipp-usb  daemon  enables driver-less printing and scanning on USB-only AirPrint-compatible
       printers and MFPs.

       It works by connecting to the device by USB using IPP-over-USB protocol, and exposing  the
       device to the network, including DNS-SD (ZeroConf) advertising.

       IPP printing, eSCL scanning and web console are fully supported.

SYNOPSIS

   Usage:
       ipp-usb mode [options]

   Modes are:
       standalone
              run forever, automatically discover IPP-over-USB devices and serve them all

       udev   like standalone, but exit when last IPP-over-USB device is disconnected

       debug  logs duplicated on console, -bg option is ignored

       check  check configuration and exit. It also prints a list of all connected devices

       status print  status of the running ipp-usb daemon, including information of all connected
              devices

   Options are
       -bg    run in background (ignored in debug mode)

NETWORKING

       Essentially, ipp-usb makes printer or scanner  accessible  from  the  network,  converting
       network-side HTTP operations to the USB operations.

       By  default,  ipp-usb  exposes  device only to the loopback interface, using the localhost
       address (both 127.0.0.1 and ::1, for IPv4 and IPv6, respectively). TCP ports are allocated
       automatically,  and allocation is persisted in the association with the particular device,
       so the next time the device is plugged on, it will get the same  port.  The  default  port
       range for TCP ports allocation is 60000-65535.

       This  default behavior can be changed, using configuration file. See CONFIGURATION section
       below for details.

       If you decide to publish your device to the real network, the following things  should  be
       taken into consideration:

       1.  Your  private  device  will  become  public  and  it  will  become accessible by other
           computers from the network

       2.  Firewall rules needs to be updated appropriately. The ipp-usb daemon will  not  do  it
           automatically by itself

       3.  IPP  over USB specification explicitly require that the Host field in the HTTP request
           is set to localhost or localhost:port. If device is accessed from  the  real  network,
           Host  header will reflect the real network address. Most of devices allow it, but some
           are more restrictive and will not work in this configuration.

DNS-SD (AVAHI INTEGRATION)

       IPP over USB is intended to be used with the automatic  device  discovery,  and  for  this
       purpose ipp-usb advertises all devices it handles, using DNS-SD protocol. On Linux, DNS-SD
       is handled with a help of Avahi daemon.

       DNS-SD advertising can be disabled via configuration file. Also, if Avahi is not installed
       or  not  running,  ipp-usb will still work correctly, although DNS-SD advertising will not
       work.

       For every device the following services will be advertised:

       ┌────────────┬───────────────┬───────────────────────────┐
       │Instance    │ Type          │ Subtypes                  │
       ├────────────┼───────────────┼───────────────────────────┤
       │Device name │ _ipp._tcp     │ _universal._sub._ipp._tcp │
       ├────────────┼───────────────┼───────────────────────────┤
       │Device name │ _printer._tcp │                           │
       ├────────────┼───────────────┼───────────────────────────┤
       │Device name │ _uscan._tcp   │                           │
       ├────────────┼───────────────┼───────────────────────────┤
       │Device name │ _http._tcp    │                           │
       ├────────────┼───────────────┼───────────────────────────┤
       │BBPP        │ _ipp-usb._tcp │                           │
       └────────────┴───────────────┴───────────────────────────┘
       Notes:

       ○   Device name is the name under which device appears in the list of  available  devices,
           for  example, in the printing dialog (it is DNS-SD device name, in another words), and
           for most of devices will match the device's model name. It  is  appended  with  the  "
           (USB)" suffix, so if device is connected via network and via USB simultaneously, these
           two connections can be easily distinguished. If there are two devices  with  the  same
           name connected simultaneously, the suffix becomes " (USB NNN)", with NNN number unique
           for each device, for disambiguation. In another  words,  the  single  "Kyocera  ECOSYS
           M2040dn"  device  will  be  listed  as  "Kyocera ECOSYS M2040dn (USB)", and two such a
           devices will be listed as "Kyocera ECOSYS M2040dn (USB 1)" and "Kyocera ECOSYS M2040dn
           (USB 2)"_ipp._tcp and _printer._tcp are only advertises for printer devices and MFPs

       ○   _uscan._tcp is only advertised for scanner devices and MFPs

       ○   for  the  _ipp._tcp  service, the _universal._sub._ipp._tcp subtype is also advertised
           for iOS compatibility

       ○   _printer._tcp is advertised with TCP port set to 0. Other services are advertised with
           the actual port number

       ○   _http._tcp  is  device web-console. It is always advertises in assumption it is always
           exist

       ○   BBPP, used for the _ipp-usb._tcp service, is the USB bus (BB) and port (PP) numbers in
           hex.  The  purpose of this advertising is to help CUPS and other possible "clients" to
           guess which devices are handled by the ipp-usb service, to  avoid  possible  conflicts
           with the legacy USB drivers.

CONFIGURATION

       ipp-usb searched for its configuration file in two places:

       1.  /etc/ipp-usb/ipp-usb.conf

       2.  ipp-usb.conf in the directory where executable file is located

       Configuration  file  syntax  is  very  similar  to  .INI files syntax. It consist of named
       sections, and each section contains a set of named variables. Comments are started from  #
       or ; characters and continues until end of line:

           # This is a comment
           [section 1]
           variable 1 = value 1  ; and another comment
           variable 2 = value 2

   Network parameters
       Network parameters are all in the [network] section:

           [network]
             # TCP ports for HTTP will be automatically allocated in the
             # following range
             http-min-port = 60000
             http-max-port = 65535

             # Enable or disable DNS-SD advertisement
             dns-sd = enable      # enable | disable

             # Network interface to use. Set to `all` if you want to expose you
             # printer to the local network. This way you can share your printer
             # with other computers in the network, as well as with iOS and
             # Android devices.
             interface = loopback # all | loopback

             # Enable or disable IPv6
             ipv6 = enable        # enable | disable

   Logging configuration
       Logging parameters are all in the [logging] section:

           [logging]
             # device-log  - what logs are generated per device
             # main-log    - what common logs are generated
             # console-log - what of generated logs goes to console
             #
             # parameter contains a comma-separated list of
             # the following keywords:
             #   error     - error messages
             #   info      - informative messages
             #   debug     - debug messages
             #   trace-ipp, trace-escl, trace-http - very detailed
             #               per-protocol traces
             #   trace-usb - hex dump of all USB traffic
             #   all       - all logs
             #   trace-all - alias to all
             #
             # Note, trace-* implies debug, debug implies info, info implies
             # error
             device-log    = all
             main-log      = debug
             console-log   = debug

             # Log rotation parameters:
             #   log-file-size    - max log file before rotation. Use suffix
             #                      M for megabytes or K for kilobytes
             #   log-backup-files - how many backup files to preserve during
             #                      rotation
             #
             max-file-size    = 256K
             max-backup-files = 5

             # Enable or disable ANSI colors on console
             console-color = enable # enable | disable

   Quirks
       Some devices, due to their firmware bugs, require special handling, called device-specific
       quirks. ipp-usb loads quirks from the /usr/share/ipp-usb/quirks/*.conf files and from  the
       /etc/ipp-usb/quirks/*.conf  files.  The /etc/ipp-usb/quirks directory is for system quirks
       overrides or admin changes. These files have .INI-file syntax with the content that  looks
       like this:

           [HP LaserJet MFP M28-M31]
             http-connection = keep-alive

           [HP OfficeJet Pro 8730]
             http-connection = close

           [HP Inc. HP Laser MFP 135a]
             blacklist = true

           # Default configuration
           [*]
             http-connection = ""

       For  each  discovered  device,  its  model  name is matched against sections of the quirks
       files. Section names may contain glob-style wildcards: *  that  matches  any  sequence  of
       characters  and ? , that matches any single character. To match one of these characters (*
       and ?) literally, use backslash as escape.

       Note, the simplest way to guess the exact model name for the particular device is  to  use
       ipp-usb check command, which prints a list of all connected devices.

       All  matching  sections  from  all quirks files are taken in consideration, and applied in
       priority order. Priority is computed using the following algorithm:

       ○   When matching  model  name  against  section  name,  amount  of  non-wildcard  matched
           characters is counted, and the longer match wins

       ○   Otherwise, section loaded first wins. Files are loaded in alphabetical order, sections
           read sequentially

       If some parameter exist in multiple sections,  used  its  value  from  the  most  priority
       section

       The following parameters are defined:

       ○   blacklist = true | false
           If true, the matching device is ignored by the ipp-usbhttp-XXX = YYY
           Set  XXX  header  of  the  HTTP  requests  forwarded to device to YYY. If YYY is empty
           string, XXX header is removed

       ○   usb-max-interfaces = N
           Don't use more that N USB interfaces, even if more is available

       ○   disable-fax = true | false
           If true, the matching device's fax capability is ignored

       ○   init-reset = none | soft | hard
           How to reset device during initialization. Default is noneinit-delay = NNN
           Delay, in milliseconds, between device is opened and, optionally, reset, and the first
           request is sent to device

       ○   request-delay = NNN
           Delay, in milliseconds, between subsequent requests

       If  you  found out about your device that it needs a quirk to work properly or it does not
       work with ipp-usb at all, although it provides IPP-over-USB interface, please  report  the
       issue  at https://github.com/OpenPrinting/ipp-usb. It will let us to update our collection
       of quirks, so helping other owners of such a device.

FILES

/etc/ipp-usb/ipp-usb.conf: the daemon configuration file

       ○   /var/log/ipp-usb/main.log: the main log file

       ○   /var/log/ipp-usb/<DEVICE>.log: per-device log files

       ○   /var/ipp-usb/dev/<DEVICE>.state: device state (HTTP port allocation, DNS-SD name)

       ○   /var/ipp-usb/lock/ipp-usb.lock: lock file, that helps to prevent  multiple  copies  of
           daemon to run simultaneously

       ○   /var/ipp-usb/ctrl:   ipp-usb  control  socket.  Currently  only  used  to  obtain  the
           per-device status (printed by ipp-usb status), but its functionality may  be  extended
           in a future

       ○   /usr/share/ipp-usb/quirks/*.conf: device-specific quirks (see above)

       ○   /etc/ipp-usb/quirks/*.conf: device-specific quirks defined by sysadmin (see above)

COPYRIGHT

       Copyright (c) by Alexander Pevzner (pzz@apevzner.com, pzz@pzz.msk.ru)
       All rights reserved.

       This program is licensed under 2-Clause BSD license. See LICENSE file for details.

SEE ALSO

       cups(1)

                                          December 2022                                IPP-USB(8)