Changes in OpenPrinting CUPS

CUPS v2.4rc1 (Pending)

Added support for CUPS running in a Snapcraft snap.
Added support for AirPrint and Mopria clients (Issue #105)
Added configure support for specifying systemd dependencies in the CUPS service file (Issue #144)
Added several features and improvements to ipptool (Issue #153)
The ipptool command now correctly reports an error when a test file cannot be found.
Fixed Kerberos authentication for the web interface (Issue #19)
The ZPL sample driver now supports more "standard" label sizes (Issue #70)
Fixed reporting of printer instances when enumerating and when no options are set for the main instance (Issue #71)
Reverted USB read limit enforcement change from CUPS 2.2.12 (Issue #72)
The IPP backend did not return the correct status code when a job was canceled at the printer/server (Issue #74)
The testlang unit test program now loops over all of the available locales by default (Issue #85)
The cupsfilter command now shows error messages when options are used incorrectly (Issue #88)
The PPD functions now treat boolean values as case-insensitive (Issue #106)
Temporary queue names no longer end with an underscore (Issue #110)
The USB backend now runs as root (Issue #121)
Added pkg-config file for libcups (Issue #122)
Fixed a PPD memory leak caused by emulator definitions (Issue #124)
Fixed a DISPLAY bug in ipptool (Issue #139)
The scheduler now includes the [Job N] prefix for job log messages, even when using syslog logging (Issue #154)
Added support for locales using the GB18030 character set (Issue #159)
httpReconnect2 did not reset the socket file descriptor when the TLS negotiation failed (Apple #5907)
httpUpdate did not reset the socket file descriptor when the TLS negotiation failed (Apple #5915)
The IPP backend now retries Validate-Job requests (Issue #132)
Added a workaround for Solaris in httpAddrConnect2 (Issue #156)
Now use a 60 second timeout for reading USB backchannel data (Issue #160)
The USB backend now tries harder to find a serial number (Issue #170)
Fixed @IF(name) handling in cupsd.conf (Apple #5918)
Now always pass "localhost" in the Host: header when talking over a domain socket or the loopback interface (Issue #185)
Fixed a job history update issue in the scheduler (Issue #187)
Fixed job-pages-per-set value for duplex print jobs.
Fixed an edge case in ippReadIO to make sure that only complete attributes and values are retained on an error (Issue #195)
Hardened ippReadIO to prevent invalid IPP messages from being propagated (Issue #195, Issue #196)
The scheduler now supports the "everywhere" model directly (Issue #201)
Documentation fixes (Issue #92, Issue #163, Issue #177, Issue #184)
Localization updates (Issue #123, Issue #129, Issue #134, Issue #146, Issue #164)
USB quirk updates (Issue #192, Apple #5766, Apple #5838, Apple #5843, Apple #5867)
Web interface updates (Issue #142)
The ippeveprinter tool now automatically uses an available port.
Fixed some Windows issues.
Deprecated cups-config (Issue #97)
Deprecated Kerberos (AuthType Negotiate) authentication (Issue #98)
Removed support for the (long deprecated and unused) FontPath, LPDConfigFile, KeepAliveTimeout, RIPCache, and SMBConfigFile directives in cupsd.conf and cups-files.conf.

CUPS v2.3.3op2 (February 1, 2021)

Security: Fixed a buffer (read) overflow in the ippReadIO function (CVE-2020-10001)
Clarified the documentation for the "Listen" directive (Issue #53)
Fixed duplicate ColorModel entries for AirPrint printers (Issue 59)
Fixed directory/permission defaults for Debian kfreebsd-based systems (Issue #60, Issue #61)
Fixed crash bug in ppdOpen (Issue #64, Issue #78)
Fixed regression in snprintf emulation function (Issue #67)
The scheduler's systemd service file now waits for the nslcd service to start (Issue #69)
The libusb-based USB backend now uses a simpler read timer implementation to avoid a regression in a previous change (Issue #72)
The PPD caching code now only tracks the APPrinterIconPath value on macOS (Issue #73)
Fixed segfault in help.cgi when searching in man pages (Issue #81)
Root certificates were incorrectly stored in "~/.cups/ssl".

CUPS v2.3.3op1 (November 27, 2020)

The automated test suite can now be activated using make test for consistency with other projects and CI environments - the old make check continues to work as well, and the previous test server behavior can be accessed by running make testserver.
ippeveprinter now supports multiple icons and strings files.
ippeveprinter now uses the system's FQDN with Avahi.
ippeveprinter now supports Get-Printer-Attributes on "/".
ippeveprinter now uses a deterministic "printer-uuid" value.
ippeveprinter now uses system sounds on macOS for Identify-Printer.
Updated ippfind to look for files in "~/Desktop" on Windows.
Updated ippfind to honor SKIP-XXX directives with PAUSE.
Updated IPP Everywhere support to work around printers that only advertise color raster support but really also support grayscale (Issue #1)
ipptool now supports DNS-SD URIs like ipps://My%20Printer._ipps._tcp.local (Issue #5)
The scheduler now allows root backends to have world read permissions but not world execute permissions (Issue #21)
Failures to bind IPv6 listener sockets no longer cause errors if IPv6 is disabled on the host (Issue #25)
The SNMP backend now supports the HP and Ricoh vendor MIBs (Issue #28)
The scheduler no longer includes a timestamp in files it writes (Issue #29)
The systemd service names are now "cups.service" and "cups-lpd.service" (Issue #30, Issue #31)
The scheduler no longer adds the local hostname to the ServerAlias list (Issue #32)
Added LogFileGroup directive in "cups-files.conf" to control the group owner of log files (Issue #34)
Added --with-max-log-size configure option (Issue #35)
Added --enable-sync-on-close configure option (Issue #37)
Added --with-error-policy configure option (Issue #38)
IPP Everywhere PPDs could have an "unknown" default InputSlot (Issue #44)
The httpAddrListen function now uses a listen backlog of 128.
Added USB quirks (Apple issue #5789, #5823, #5831)
Fixed IPP Everywhere v1.1 conformance issues in ippeveprinter.
Fixed DNS-SD name collision support in ippeveprinter.
Fixed compiler and code analyzer warnings.
Fixed TLS support on Windows.
Fixed ippfind sub-type searches with Avahi.
Fixed the default hostname used by ippeveprinter on macOS.
Fixed resolution of local IPP-USB printers with Avahi.
Fixed coverity issues (Issue #2)
Fixed httpAddrConnect issues (Issue #3)
Fixed web interface device URI issue (Issue #4)
Fixed lp/lpr "printer/class not found" error reporting (Issue #6)
Fixed xinetd support for LPD clients (Issue #7)
Fixed libtool build issue (Issue #11)
Fixed a memory leak in the scheduler (Issue #12)
Fixed a potential integer overflow in the PPD hashing code (Issue #13)
Fixed output-bin and print-quality handling issues (Issue #18)
Fixed PPD options getting mapped to odd IPP values like "tray---4" (Issue #23)
Fixed remote access to the cupsd.conf and log files (Issue #24)
Fixed the automated test suite when running in certain build/CI environments (Issue #25)
Fixed a logging regression caused by a previous change for Apple issue #5604 (Issue #25)
Fixed fax phone number handling with GNOME (Issue #40)
Fixed potential rounding error in rastertopwg filter (Issue #41)
Fixed the "uri-security-supported" value from the scheduler (Issue #42)
Fixed IPP backend crash bug with "printer-alert" values (Issue #43)
Removed old Solaris inetconv(1m) reference in cups-lpd man page (Issue #46)
Fixed default options that incorrectly use the "custom" prefix (Issue #48)
Fixed a memory leak when resolving DNS-SD URIs (Issue #49)
Fixed systemd status reporting by adopting the notify interface (Issue #51)
Fixed crash in rastertopwg (Apple issue #5773)
Fixed cupsManualCopies values in IPP Everywhere PPDs (Apple issue #5807)