ldap_sync(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | GENERAL USE | REFRESH ONLY | REFRESH AND PERSIST | ERRORS | NOTES | SEE ALSO | AUTHOR | ACKNOWLEDGEMENTS | COLOPHON

LDAP_SYNC(3)            Library Functions Manual            LDAP_SYNC(3)

NAME         top

       ldap_sync_init, ldap_sync_init_refresh_only,
       ldap_sync_init_refresh_and_persist, ldap_sync_poll - LDAP sync
       routines

LIBRARY         top

       OpenLDAP LDAP (libldap, -lldap)

SYNOPSIS         top

       #include <ldap.h>

       int ldap_sync_init(ldap_sync_t *ls, int mode);

       int ldap_sync_init_refresh_only(ldap_sync_t *ls);

       int ldap_sync_init_refresh_and_persist(ldap_sync_t *ls);

       int ldap_sync_poll(ldap_sync_t *ls);

       ldap_sync_t * ldap_sync_initialize(ldap_sync_t *ls);

       void ldap_sync_destroy(ldap_sync_t *ls, int freeit);

       typedef int (*ldap_sync_search_entry_f)(ldap_sync_t *ls,
              LDAPMessage *msg, struct berval *entryUUID,
              ldap_sync_refresh_t phase);

       typedef int (*ldap_sync_search_reference_f)(ldap_sync_t *ls,
              LDAPMessage *msg);

       typedef int (*ldap_sync_intermediate_f)(ldap_sync_t *ls,
              LDAPMessage *msg, BerVarray syncUUIDs,
              ldap_sync_refresh_t phase);

       typedef int (*ldap_sync_search_result_f)(ldap_sync_t *ls,
              LDAPMessage *msg, int refreshDeletes);

DESCRIPTION         top

       These routines provide an interface to the LDAP Content
       Synchronization operation (RFC 4533).  They require an
       ldap_sync_t structure to be set up with parameters required for
       various phases of the operation; this includes setting some
       handlers for special events.  All handlers take a pointer to the
       ldap_sync_t structure as the first argument, and a pointer to the
       LDAPMessage structure as received from the server by the client
       library, plus, occasionally, other specific arguments.

       The members of the ldap_sync_t structure are:

       char *ls_base
              The search base; by default, the BASE option in
              ldap.conf(5).

       int ls_scope
              The search scope (one of LDAP_SCOPE_BASE,
              LDAP_SCOPE_ONELEVEL, LDAP_SCOPE_SUBORDINATE or
              LDAP_SCOPE_SUBTREE; see ldap.h for details).

       char *ls_filter
              The filter (RFC 4515); by default, (objectClass=*).

       char **ls_attrs
              The requested attributes; by default NULL, indicating all
              user attributes.

       int ls_timelimit
              The requested time limit (in seconds); by default 0, to
              indicate no limit.

       int ls_sizelimit
              The requested size limit (in entries); by default 0, to
              indicate no limit.

       int ls_timeout
              The desired timeout during polling with ldap_sync_poll(3).
              A value of -1 means that polling is blocking, so
              ldap_sync_poll(3) will not return until a message is
              received; a value of 0 means that polling returns
              immediately, no matter if any response is available or
              not; a positive value represents the timeout the
              ldap_sync_poll(3) function will wait for response before
              returning, unless a message is received; in that case,
              ldap_sync_poll(3) returns as soon as the message is
              available.

       ldap_sync_search_entry_f ls_search_entry
              A function that is called whenever an entry is returned.
              The msg argument is the LDAPMessage that contains the
              searchResultEntry; it can be parsed using the regular
              client API routines, like ldap_get_dn(3),
              ldap_first_attribute(3), and so on.  The entryUUID
              argument contains the entryUUID of the entry.  The phase
              argument indicates the type of operation: one of
              LDAP_SYNC_CAPI_PRESENT, LDAP_SYNC_CAPI_ADD,
              LDAP_SYNC_CAPI_MODIFY, LDAP_SYNC_CAPI_DELETE; in case of
              LDAP_SYNC_CAPI_PRESENT or LDAP_SYNC_CAPI_DELETE, only the
              DN is contained in the LDAPMessage; in case of
              LDAP_SYNC_CAPI_MODIFY, the whole entry is contained in the
              LDAPMessage, and the application is responsible of
              determining the differences between the new view of the
              entry provided by the caller and the data already known.

       ldap_sync_search_reference_f ls_search_reference
              A function that is called whenever a search reference is
              returned.  The msg argument is the LDAPMessage that
              contains the searchResultReference; it can be parsed using
              the regular client API routines, like
              ldap_parse_reference(3).

       ldap_sync_intermediate_f ls_intermediate
              A function that is called whenever something relevant
              occurs during the refresh phase of the search, which is
              marked by an intermediateResponse message type.  The msg
              argument is the LDAPMessage that contains the intermediate
              response; it can be parsed using the regular client API
              routines, like ldap_parse_intermediate(3).  The syncUUIDs
              argument contains an array of UUIDs of the entries that
              depends on the value of the phase argument.  In case of
              LDAP_SYNC_CAPI_PRESENTS, the "present" phase is being
              entered; this means that the following sequence of results
              will consist in entries in "present" sync state.  In case
              of LDAP_SYNC_CAPI_DELETES, the "deletes" phase is being
              entered; this means that the following sequence of results
              will consist in entries in "delete" sync state.  In case
              of LDAP_SYNC_CAPI_PRESENTS_IDSET, the message contains a
              set of UUIDs of entries that are present; it replaces a
              "presents" phase.  In case of
              LDAP_SYNC_CAPI_DELETES_IDSET, the message contains a set
              of UUIDs of entries that have been deleted; it replaces a
              "deletes" phase.  In case of LDAP_SYNC_CAPI_DONE, a
              "presents" phase with "refreshDone" set to "TRUE" has been
              returned to indicate that the refresh phase of
              refreshAndPersist is over, and the client should start
              polling.  Except for the LDAP_SYNC_CAPI_PRESENTS_IDSET and
              LDAP_SYNC_CAPI_DELETES_IDSET cases, syncUUIDs is NULL.

       ldap_sync_search_result_f ls_search_result
              A function that is called whenever a searchResultDone is
              returned.  In refreshAndPersist this can only occur when
              the server decides that the search must be interrupted.
              The msg argument is the LDAPMessage that contains the
              response; it can be parsed using the regular client API
              routines, like ldap_parse_result(3).  The refreshDeletes
              argument is not relevant in this case; it should always be
              -1.

       void *ls_private
              A pointer to private data.  The client may register here a
              pointer to data the handlers above may need.

       LDAP *ls_ld
              A pointer to a LDAP structure that is used to connect to
              the server.  It is the responsibility of the client to
              initialize the structure and to provide appropriate
              authentication and security in place.

GENERAL USE         top

       A ldap_sync_t structure is initialized by calling
       ldap_sync_initialize(3).  This simply clears out the contents of
       an already existing ldap_sync_t structure, and sets appropriate
       values for some members.  After that, the caller is responsible
       for setting up the connection (member ls_ld), eventually setting
       up transport security (TLS), for binding and any other
       initialization.  The caller must also fill all the documented
       search-related fields of the ldap_sync_t structure.

       At the end of a session, the structure can be cleaned up by
       calling ldap_sync_destroy(3), which takes care of freeing all
       data assuming it was allocated by ldap_mem*(3) routines.
       Otherwise, the caller should take care of destroying and zeroing
       out the documented search-related fields, and call
       ldap_sync_destroy(3) to free undocumented members set by the API.

REFRESH ONLY         top

       The refreshOnly functionality is obtained by periodically calling
       ldap_sync_init(3) with mode set to LDAP_SYNC_REFRESH_ONLY, or,
       which is equivalent, by directly calling
       ldap_sync_init_refresh_only(3).  The state of the search, and the
       consistency of the search parameters, is preserved across calls
       by passing the ldap_sync_t structure as left by the previous
       call.

REFRESH AND PERSIST         top

       The refreshAndPersist functionality is obtained by calling
       ldap_sync_init(3) with mode set to LDAP_SYNC_REFRESH_AND_PERSIST,
       or, which is equivalent, by directly calling
       ldap_sync_init_refresh_and_persist(3) and, after a successful
       return, by repeatedly polling with ldap_sync_poll(3) according to
       the desired pattern.

       A client may insert a call to ldap_sync_poll(3) into an external
       loop to check if any modification was returned; in this case, it
       might be appropriate to set ls_timeout to 0, or to set it to a
       finite, small value.  Otherwise, if the client's main purpose
       consists in waiting for responses, a timeout of -1 is most
       suitable, so that the function only returns after some data has
       been received and handled.

ERRORS         top

       All routines return any LDAP error resulting from a lower-level
       error in the API calls they are based on, or LDAP_SUCCESS in case
       of success.  ldap_sync_poll(3) may return
       LDAP_SYNC_REFRESH_REQUIRED if a full refresh is requested by the
       server.  In this case, it is appropriate to call
       ldap_sync_init(3) again, passing the same ldap_sync_t structure
       as resulted from any previous call.

NOTES         top


SEE ALSO         top

       ldap(3), ldap_search_ext(3), ldap_result(3); RFC 4533
       (http://www.rfc-editor.org),

AUTHOR         top

       Designed and implemented by Pierangelo Masarati, based on RFC
       4533 and loosely inspired by syncrepl code in slapd(8).

ACKNOWLEDGEMENTS         top

       Initially developed by SysNet s.n.c.  OpenLDAP is developed and
       maintained by The OpenLDAP Project (http://www.openldap.org/).
       OpenLDAP is derived from University of Michigan LDAP 3.3 Release.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation
       of the Lightweight Directory Access Protocol) project.
       Information about the project can be found at 
       ⟨http://www.openldap.org/⟩.  If you have a bug report for this
       manual page, see ⟨http://www.openldap.org/its/⟩.  This page was
       obtained from the project's upstream Git repository
       ⟨https://git.openldap.org/openldap/openldap.git⟩ on 2023-12-22.
       (At that time, the date of the most recent commit that was found
       in the repository was 2023-12-19.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

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