For details, please check the commit history:
https://github.com/rtrlib/rtrlib/commits/master

Release History:

* Version 0.6.3
    - Fix IPv4 string conversion to support big endian systems

* Version 0.6.2
    - Add C++ support by disabling name mangling for RTRlib symbols
    - Make pfx_table, pfx_table_init(), pfx_table_add(),
      pfx_table_free(), pfx_table_src_remove() public; to use RTRlib
      without online connection to an RPKI cache server
    - Hide symbols of Tommy hash table without using forward declaration,
      to resolve dependency on C11
    - Fix cmake build errors in Debian and OpenBSD
    - Add connection timeout in tests/test_dynamic_groups

* Version 0.6.1
    - Fix for cmake versions >= 2.8
    - Fix rpm build
    - Fix Ubuntu 12.04 build

* Version 0.6.0
    - Change default symbol visibility: Hide all symbols per default,
      export public symbols explicitly
    - Add API to configure interval mode: {set,get}_interval_mod
    - Change naming of interval enumerations in rtr.h: add prefixes to
      prevent name collisions
    - Fix Debian packages: merge rtrclient and rtr-validator into one
      package, use libjs-jquery, fix copyright format, fix version
      numbering and source package format
    - Fix bug in trie structure where deletion of inner nodes may lead
      to incorrect reordering, i.e., a node with longer prefix length
      overrules nodes with shorter prefix length, which then will not
      be found anymore
    - Rename cli-validator to rpki-rov
    - Fix wrong length of error text in error pdu
    - Add atomtic reset for pfx table and spki table
    - Improve code for packets
    - Add rpm package build infrastructure
    - Add cppcheck suppresions for public api functions  
    - Add new test to verify correctness of prefix removal
    - Remove function rtr_mgr_find_group in RTR Manager because it is
      not used
    - Disable unittests for Apple macOS
    - Add man pages for tools

* Version 0.5.0
    - Add support for dynamic add and remove of socket groups in rtr_mgr
    - add memory handling wrappers (i.e. alloc utils) for FRR integration
    - extend tests to verify dynamic groups feature
    - fix duplicate socket configuration on init in {tcp,ssh}_transport
    - Improve documentation on trie implementation and for util functions

* Version 0.4.0
    - Fix bug in prefix origin AS validation caused by LPFST, which lead to
      incrrect validation results in corner caes, and change prefix storage
      structure to Trie
    - Fix memory leaks in lpfst_get_children
    - Fix memory leak in rtr_mgr_get_spki
    - Fix memory leak in rtr_mgr_init
    - Fix memory leak in pfx_table_append_elem
    - Fix memory leak in pfx_table_del_elem
    - Fix byte order for encapsulated error PDUs
    - Fix error PDU handling, do not send encapsulated PDUs on internal errors
    - Improve testing:
        - add extensive unit tests based on the Cmocka framework
        - add runtime tests, e.g. live validation of RIPE RIS BGP beacons
    - Improve overall coding style and documentation
    - Add static code analysis (cppcheck, codecov.io) to Travis CI config
    - Add backward compatibility for libssh 0.5.0 and Ubuntu 12.04 LTS
    - Update Debian package build files

* Version 0.3.6
    - rtrlib/lib/*: Change API and add lrtr_ prefix to prevent namespace
      conflicts with third party applications
    - Change API for rtr_mgr_init and rtr_init to improve error handling
    - Change preference order of finding cache servers, according to
      RFC 6810
    - Improve behavior of cache server groups, switch to preferred
      group as soon as cache server is online again
    - Improve error handling in rtr_mgr_init
    - Improve timing behavior (expire interval, refresh interval etc.)
    - Fix bug in rtr_mgr_close_all_groups_except_one to prevent deadlock
    - Fix memory leaks, race condition, and buffer overflow/underflow
    - Improve debugging and status values
    - Update SSH transport to new LibSSH API

* Version 0.3.5
    - Change license from LGPLv3 to MIT license
    - Fix bug in pfx_table_src_remove, a lock was not released
    - Fix bug in rtr_purge_outdated_records that removed prefixes
      incorrectly
    - Create and install rtrlib.pc pkg-config
    - Update code style
    - Add support for OS X (10.10)
    - Add new tool cli-validator

* Version 0.3.0
    - Added support for IETF draft draft-ietf-sidr-rpki-rtr-rfc6810-bis-02
    - Minor changes of the library API (see doxygen documentation).

* Version 0.2.4
    - rtrclient: fix rtrclient didn't compile when libssh wasn't
      installed and found by cmake

* Version 0.2.3
    - rtrclient: increase polling period from 1 to 30 seconds
    - rtrclient: bug fix for segfault caused by out-of-scope variable access
    - rtrclient: fix wrong ssh example in usage output
    - transport: remove const modifier from tr_ssh_config and
      tr_tcp_config struct members
    - cmake: install doxygen documentation to $PREFIX/share/doc/rtrlib/
    - add debian packaging files

* Version 0.2.2
    - Fixed a bug in ipv6_get_bits(..), specific IPv6 records couldn't
      be addded to the pfx_table

* Version 0.2.1
    - Nonce variable renamed to session_id to conform with
      draft-ietf-sidr-rpki-rtr-26
    - Warning message added if the Zero field of a prefix PDU doesn't
      contain 0
    - pfx_validate_r function added, returns list of prefixes which
      affected the validation state BGP route
    - Fixed bug in lpfst_remove that could cause that an pfx_record in the
      pfx_table could not be found.
    - Added state rollback to the prefix synchronization function to
      assure that the last correct state is recovered if an error occurs
      during synchronization
    - Few smaller bugfixes and debug formatting corrections

* Version 0.2
    - Support of RTR-Server failover mechanisms (RTR manager component
      implemented)
    - Automatic reconnect of rtr_socket in case of errors
    - Renamed rtr_update_fp callback to pfx_update_fp. Callback will be
      executed only if a pfx_record has been added or deleted.
    - Representation of IP addresses in host byte order within pfx_table
    - New convenience function to transform an IP address string into a
      struct ip_addr and vice versa
    - support for the IETF drafts draft-ietf-sidr-rpki-rtr-19 and
      draft-ietf-sidr-pfx-validate-03
    - Extended debug messages
    - Many bug fixes

* Version 0.1
    - Beta version
