Import OpenLDAP 2.5.6:

OpenLDAP 2.5.6 Release (2021/07/27)
Fixed libldap buffer overflow (ITS#9578)
Fixed libldap missing mutex unlock on connection alloc failure (ITS#9590)
Fixed lloadd cn=config olcBkLloadClientMaxPending setting (ITS#8747)
Fixed slapd multiple config defaults (ITS#9363)
Fixed slapd ipv6 addresses to work with tcp wrappers (ITS#9603)
Fixed slapo-syncprov delete of nonexistent sessionlog (ITS#9608)
Build
Fixed library symbol versioning on Solaris (ITS#9591)
Fixed compile warning in libldap/tpool.c (ITS#9601)
Fixed compile wraning in libldap/tls_o.c (ITS#9602)
Contrib
Fixed ppm module for sysconfdir (ITS#7832)
Documentation
Updated guide to document multival, idlexp, and maxentrysize (ITS#9613, ITS#9614)

OpenLDAP 2.5.5 Release (2021/06/03)
Added libldap LDAP_OPT_TCP_USER_TIMEOUT support (ITS#9502)
Added lloadd tcp-user-timeout support (ITS#9502)
Added slapd-asyncmeta tcp-user-timeout support (ITS#9502)
Added slapd-ldap tcp-user-timeout support (ITS#9502)
Added slapd-meta tcp-user-timeout support (ITS#9502)
Fixed incorrect control OIDs for AuthZ Identity (ITS#9542)
Fixed libldap typo in util-int.c (ITS#9541)
Fixed libldap double free of LDAP_OPT_DEFBASE (ITS#9530)
Fixed libldap better TLS1.3 cipher suite handling (ITS#9521, ITS#9546)
Fixed lloadd multiple issues (ITS#8747)
Fixed slapd slap_op_time to avoid duplicates across restarts (ITS#9537)
Fixed slapd typo in daemon.c (ITS#9541)
Fixed slapd slapi compilation (ITS#9544)
Fixed slapd to handle empty DN in extended filters (ITS#9551)
Fixed slapd syncrepl searches with empty base (ITS#6467)
Fixed slapd syncrepl refresh on startup (ITS#9324, ITS#9534)
Fixed slapd abort due to typo (ITS#9561)
Fixed slapd-asyncmeta quarantine handling (ITS#8721)
Fixed slapd-asyncmeta to have a default operations timeout (ITS#9555)
Fixed slapd-ldap quarantine handling (ITS#8721)
Fixed slapd-mdb deletion of context entry (ITS#9531)
Fixed slapd-mdb off-by-one affecting search scope (ITS#9557)
Fixed slapd-meta quarantine handling (ITS#8721)
Fixed slapo-accesslog to record reqNewDN for modRDN ops (ITS#9552)
Fixed slapo-pcache locking during expiration (ITS#9529)
Build
Fixed slappw-argon2 module installation (ITS#9548)
Contrib
Update ldapc++/ldaptcl to use configure.ac (ITS#9554)
Documentation
ldap_first_attribute(3) - Document ldap_get_attribute_ber (ITS#8820)
ldap_modify(3) - Delete non-existent mod_next parameter (ITS#9559)

OpenLDAP 2.5.4 Release (2021/04/29)
Initial release for "general use".

OpenLDAP 2.4.59 Release (2021/06/03)
Fixed libldap TLSv1.3 cipher suites with OpenSSL 1.1.1 (ITS#9521)
Fixed libldap double free of LDAP_OPT_DEFBASE (ITS#9530)
Fixed slapd syncrepl handling of add+delete on single value attr (ITS#9295)
Fixed slapd-mdb cursor init check (ITS#9526)
Fixed slapd-mdb deletion of context entry (ITS#9531)
Fixed slapd-mdb off-by-one affecting search scope (ITS#9557)
Fixed slapo-pcache locking during expiration (ITS#9529)
Contrib
Fixed slapo-autogroup to not thrash thread context (ITS#9494)
Documentation
ldap_modify(3) - Delete non-existent mod_next parameter (ITS#9559)

OpenLDAP 2.4.58 Release (2021/03/16)
Fixed slapd validity checks for issuerAndThisUpdateCheck (ITS#9454)
Fixed slapd to alloc new conn struct after freeing old one (ITS#9458)
Fixed slapd syncrepl to check all contextCSNs (ITS#9282)
Fixed slapd-bdb lockdetect config (ITS#9449)

OpenLDAP 2.4.57 Release (2021/01/18)
Fixed ldapexop to use correct return code (ITS#9417)
Fixed slapd to remove asserts in UUIDNormalize (ITS#9391)
Fixed slapd to remove assert in csnValidate (ITS#9410)
Fixed slapd validity checks for issuerAndThisUpdateCheck (ITS#9411, ITS#9427)
Fixed slapd validity checks for serialNumberAndIssuerCheck (ITS#9404, ITS#9424)
Fixed slapd AVA sort with invalid RDN (ITS#9412)
Fixed slapd ldap_X509dn2bv to check for invalid BER after RDN count (ITS#9423, ITS#9425)
Fixed slapd saslauthz to remove asserts in validation (ITS#9406, ITS#9407)
Fixed slapd saslauthz to use slap_sl_free on normalized DN (ITS#9409)
Fixed slapd saslauthz SEGV in slap_parse_user (ITS#9413)
Fixed slapd modrdn memory leak (ITS#9420)
Fixed slapd double-free in vrfilter (ITS#9408)
Fixed slapd cancel operation to correctly terminate (ITS#9428)
Fixed slapd-ldap fix binds on retry with closed connection (ITS#9400)
Fixed slapo-syncprov to ignore duplicate sessionlog entries (ITS#9394)

OpenLDAP 2.4.56 Release (2020/11/10)
Fixed slapd to remove assert in certificateListValidate (ITS#9383)
Fixed slapd to remove assert in csnNormalize23 (ITS#9384)
Fixed slapd to better parse ldapi listener URIs (ITS#9379)

OpenLDAP 2.4.55 Release (2020/10/26)
Fixed slapd normalization handling with modrdn (ITS#9370)
Fixed slapd-meta to check ldap_install_tls return code (ITS#9366)
Contrib
Fixed nssov misplaced semicolon (ITS#8731, ITS#9368)

OpenLDAP 2.4.54 Release (2020/10/12)
Fixed slapd delta-syncrepl to ignore delete ops on deleted entry (ITS#9342)
Fixed slapd delta-syncrepl to be fully serialized (ITS#9330)
Fixed slapd delta-syncrepl MOD on zero-length context entry (ITS#9352)
Fixed slapd syncrepl to be fully serialized (ITS#8102)
Fixed slapd syncrepl to call check_syncprov on fresh consumer (ITS#9345)
Fixed slapd syncrepl to propagate errors from overlay_entry_get_ov (ITS#9355)
Fixed slapd syncrepl to not create empty ADD ops (ITS#9359)
Fixed slapd syncrepl replace usage on single valued attrs (ITS#9295)
Fixed slapd-monitor fix monitor_back_register_database for empty suffix DB (ITS#9353)
Fixed slapo-accesslog normalizer for reqStart (ITS#9358)
Fixed slapo-accesslog to not generate new contextCSN on purge (ITS#9361)
Fixed slapo-syncprov contextCSN generation with empty suffix (ITS#9015)
Fixed slapo-syncprov sessionlog to use a TAVL tree (ITS#8486)

OpenLDAP 2.4.53 Release (2020/09/07)
Added slapd syncrepl additional SYNC logging (ITS#9043)
Fixed slapd syncrepl segfault on NULL cookie on REFRESH (ITS#9282)
Fixed slapd syncrepl to use fresh connection on REFRESH fallback (ITS#9338)
Fixed slapo-ppolicy race condition for pwdFailureTime (ITS#9302,ITS#9334)
Build
Require OpenSSL 1.0.2 or later (ITS#9323)
Fixed libldap compilation issue with broken C compilers (ITS#9332)

OpenLDAP 2.4.52 Release (2020/08/28)
Added libldap LDAP_OPT_X_TLS_REQUIRE_SAN option (ITS#9318)
Added libldap OpenSSL support for multiple EECDH curves (ITS#9054)
Added slapd OpenSSL support for multiple EECDH curves (ITS#9054)
Fixed librewrite malloc/free corruption (ITS#9249)
Fixed libldap hang when using UDP and server down (ITS#9328)
Fixed slapd syncrepl rare deadlock due to network issues (ITS#9324)
Fixed slapd syncrepl regression that could trigger an assert (ITS#9329)
Fixed slapd-mdb index error with collapsed range (ITS#9135)

OpenLDAP 2.4.51 Release (2020/08/11)
Added slapo-ppolicy implement Netscape password policy controls (ITS#9279)
Fixed libldap retry loop in ldap_int_tls_connect (ITS#8650)
Fixed libldap to use getaddrinfo in ldap_pvt_get_fqdn (ITS#9287)
Fixed slapd to enforce singular existence of some overlays (ITS#9309)
Fixed slapd syncrepl to not delete non-replicated attrs (ITS#9227)
Fixed slapd syncrepl to correctly delete entries on resync (ITS#9282)
Fixed slapd syncrepl to use replace on single valued attrs (ITS#9294, ITS#9295)
Fixed slapd-perl dynamic config with threaded slapd (ITS#7573)
Fixed slapo-ppolicy to expose the ppolicy control (ITS#9285)
Fixed slapo-ppolicy race condition for pwdFailureTime (ITS#9302)
Fixed slapo-ppolicy so it can only exist once per DB (ITS#9309)
Fixed slapo-chain to check referral (ITS#9262)
Build Environment
Fix test064 so it no longer uses bashisms (ITS#9263)
Contrib
Fix default prefix value for pw-argon2, pw-pbkdf2 modules (ITS#9248)
slapo-allowed - Fix usage of uninitialized variable (ITS#9308)
Documentation
ldap_parse_result(3) - Document ldap_parse_intermediate (ITS#9271)