syncprov.c

ldap服务器源码

/* $OpenLDAP: pkg/ldap/servers/slapd/overlays/syncprov.c,v 1.56.2.42 2007/02/07 01:51:36 hyc Exp $ */
/* syncprov.c - syncrepl provider */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
 *
 * Copyright 2004-2007 The OpenLDAP Foundation.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted only as authorized by the OpenLDAP
 * Public License.
 *
 * A copy of this license is available in the file LICENSE in the
 * top-level directory of the distribution or, alternatively, at
 * <http://www.OpenLDAP.org/license.html>.
 */
/* ACKNOWLEDGEMENTS:
 * This work was initially developed by Howard Chu for inclusion in
 * OpenLDAP Software.
 */

#include "portable.h"

#ifdef SLAPD_OVER_SYNCPROV

#include <ac/string.h>
#include "lutil.h"
#include "slap.h"
#include "config.h"
#include "ldap_rq.h"

/* A modify request on a particular entry */
typedef struct modinst {
	struct modinst *mi_next;
	Operation *mi_op;
} modinst;

typedef struct modtarget {
	struct modinst *mt_mods;
	struct modinst *mt_tail;
	Operation *mt_op;
	ldap_pvt_thread_mutex_t mt_mutex;
} modtarget;

/* A queued result of a persistent search */
typedef struct syncres {
	struct syncres *s_next;
	struct berval s_dn;
	struct berval s_ndn;
	struct berval s_uuid;
	struct berval s_csn;
	char s_mode;
	char s_isreference;
} syncres;

/* Record of a persistent search */
typedef struct syncops {
	struct syncops *s_next;
	struct berval	s_base;		/* ndn of search base */
	ID		s_eid;		/* entryID of search base */
	Operation	*s_op;		/* search op */
	int		s_rid;
	struct berval s_filterstr;
	int		s_flags;	/* search status */
#define	PS_IS_REFRESHING	0x01
#define	PS_IS_DETACHED		0x02
#define	PS_WROTE_BASE		0x04
#define	PS_FIND_BASE		0x08
#define	PS_FIX_FILTER		0x10

	int		s_inuse;	/* reference count */
	struct syncres *s_res;
	struct syncres *s_restail;
	struct re_s	*s_qtask;	/* task for playing psearch responses */
#define	RUNQ_INTERVAL	36000	/* a long time */
	ldap_pvt_thread_mutex_t	s_mutex;
} syncops;

/* A received sync control */
typedef struct sync_control {
	struct sync_cookie sr_state;
	int sr_rhint;
} sync_control;

#if 0 /* moved back to slap.h */
#define	o_sync	o_ctrlflag[slap_cids.sc_LDAPsync]
#endif
/* o_sync_mode uses data bits of o_sync */
#define	o_sync_mode	o_ctrlflag[slap_cids.sc_LDAPsync]

#define SLAP_SYNC_NONE					(LDAP_SYNC_NONE<<SLAP_CONTROL_SHIFT)
#define SLAP_SYNC_REFRESH				(LDAP_SYNC_REFRESH_ONLY<<SLAP_CONTROL_SHIFT)
#define SLAP_SYNC_PERSIST				(LDAP_SYNC_RESERVED<<SLAP_CONTROL_SHIFT)
#define SLAP_SYNC_REFRESH_AND_PERSIST	(LDAP_SYNC_REFRESH_AND_PERSIST<<SLAP_CONTROL_SHIFT)

/* Record of which searches matched at premodify step */
typedef struct syncmatches {
	struct syncmatches *sm_next;
	syncops *sm_op;
} syncmatches;

/* Session log data */
typedef struct slog_entry {
	struct slog_entry *se_next;
	struct berval se_uuid;
	struct berval se_csn;
	ber_tag_t	se_tag;
} slog_entry;

typedef struct sessionlog {
	struct berval	sl_mincsn;
	int		sl_num;
	int		sl_size;
	slog_entry *sl_head;
	slog_entry *sl_tail;
	ldap_pvt_thread_mutex_t sl_mutex;
} sessionlog;

/* The main state for this overlay */
typedef struct syncprov_info_t {
	syncops		*si_ops;
	struct berval	si_ctxcsn;	/* ldapsync context */
	int		si_chkops;	/* checkpointing info */
	int		si_chktime;
	int		si_numops;	/* number of ops since last checkpoint */
	int		si_nopres;	/* Skip present phase */
	int		si_usehint;	/* use reload hint */
	time_t	si_chklast;	/* time of last checkpoint */
	Avlnode	*si_mods;	/* entries being modified */
	sessionlog	*si_logs;
	ldap_pvt_thread_rdwr_t	si_csn_rwlock;
	ldap_pvt_thread_mutex_t	si_ops_mutex;
	ldap_pvt_thread_mutex_t	si_mods_mutex;
	char		si_ctxcsnbuf[LDAP_LUTIL_CSNSTR_BUFSIZE];
} syncprov_info_t;

typedef struct opcookie {
	slap_overinst *son;
	syncmatches *smatches;
	struct berval sdn;	/* DN of entry, for deletes */
	struct berval sndn;
	struct berval suuid;	/* UUID of entry */
	struct berval sctxcsn;
	int sreference;	/* Is the entry a reference? */
} opcookie;

typedef struct fbase_cookie {
	struct berval *fdn;	/* DN of a modified entry, for scope testing */
	syncops *fss;	/* persistent search we're testing against */
	int fbase;	/* if TRUE we found the search base and it's still valid */
	int fscope;	/* if TRUE then fdn is within the psearch scope */
} fbase_cookie;

static AttributeName csn_anlist[3];
static AttributeName uuid_anlist[2];

/* Build a LDAPsync intermediate state control */
static int
syncprov_state_ctrl(
	Operation	*op,
	SlapReply	*rs,
	Entry		*e,
	int		entry_sync_state,
	LDAPControl	**ctrls,
	int		num_ctrls,
	int		send_cookie,
	struct berval	*cookie )
{
	Attribute* a;
	int ret;

	BerElementBuffer berbuf;
	BerElement *ber = (BerElement *)&berbuf;

	struct berval	entryuuid_bv = BER_BVNULL;

	ber_init2( ber, 0, LBER_USE_DER );
	ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );

	ctrls[num_ctrls] = op->o_tmpalloc( sizeof ( LDAPControl ), op->o_tmpmemctx );

	for ( a = e->e_attrs; a != NULL; a = a->a_next ) {
		AttributeDescription *desc = a->a_desc;
		if ( desc == slap_schema.si_ad_entryUUID ) {
			entryuuid_bv = a->a_nvals[0];
			break;
		}
	}

	/* FIXME: what if entryuuid is NULL or empty ? */

	if ( send_cookie && cookie ) {
		ber_printf( ber, "{eOON}",
			entry_sync_state, &entryuuid_bv, cookie );
	} else {
		ber_printf( ber, "{eON}",
			entry_sync_state, &entryuuid_bv );
	}

	ctrls[num_ctrls]->ldctl_oid = LDAP_CONTROL_SYNC_STATE;
	ctrls[num_ctrls]->ldctl_iscritical = (op->o_sync == SLAP_CONTROL_CRITICAL);
	ret = ber_flatten2( ber, &ctrls[num_ctrls]->ldctl_value, 1 );

	ber_free_buf( ber );

	if ( ret < 0 ) {
		Debug( LDAP_DEBUG_TRACE,
			"slap_build_sync_ctrl: ber_flatten2 failed\n",
			0, 0, 0 );
		send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
		return ret;
	}

	return LDAP_SUCCESS;
}

/* Build a LDAPsync final state control */
static int
syncprov_done_ctrl(
	Operation	*op,
	SlapReply	*rs,
	LDAPControl	**ctrls,
	int			num_ctrls,
	int			send_cookie,
	struct berval *cookie,
	int			refreshDeletes )
{
	int ret;
	BerElementBuffer berbuf;
	BerElement *ber = (BerElement *)&berbuf;

	ber_init2( ber, NULL, LBER_USE_DER );
	ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );

	ctrls[num_ctrls] = op->o_tmpalloc( sizeof ( LDAPControl ), op->o_tmpmemctx );

	ber_printf( ber, "{" );
	if ( send_cookie && cookie ) {
		ber_printf( ber, "O", cookie );
	}
	if ( refreshDeletes == LDAP_SYNC_REFRESH_DELETES ) {
		ber_printf( ber, "b", refreshDeletes );
	}
	ber_printf( ber, "N}" );

	ctrls[num_ctrls]->ldctl_oid = LDAP_CONTROL_SYNC_DONE;
	ctrls[num_ctrls]->ldctl_iscritical = (op->o_sync == SLAP_CONTROL_CRITICAL);
	ret = ber_flatten2( ber, &ctrls[num_ctrls]->ldctl_value, 1 );

	ber_free_buf( ber );

	if ( ret < 0 ) {
		Debug( LDAP_DEBUG_TRACE,
			"syncprov_done_ctrl: ber_flatten2 failed\n",
			0, 0, 0 );
		send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
		return ret;
	}

	return LDAP_SUCCESS;
}

static int
syncprov_sendinfo(
	Operation	*op,
	SlapReply	*rs,
	int			type,
	struct berval *cookie,
	int			refreshDone,
	BerVarray	syncUUIDs,
	int			refreshDeletes )
{
	BerElementBuffer berbuf;
	BerElement *ber = (BerElement *)&berbuf;
	struct berval rspdata;

	int ret;

	ber_init2( ber, NULL, LBER_USE_DER );
	ber_set_option( ber, LBER_OPT_BER_MEMCTX, &op->o_tmpmemctx );

	if ( type ) {
		switch ( type ) {
		case LDAP_TAG_SYNC_NEW_COOKIE:
			ber_printf( ber, "tO", type, cookie );
			break;
		case LDAP_TAG_SYNC_REFRESH_DELETE:
		case LDAP_TAG_SYNC_REFRESH_PRESENT:
			ber_printf( ber, "t{", type );
			if ( cookie ) {
				ber_printf( ber, "O", cookie );
			}
			if ( refreshDone == 0 ) {
				ber_printf( ber, "b", refreshDone );
			}
			ber_printf( ber, "N}" );
			break;
		case LDAP_TAG_SYNC_ID_SET:
			ber_printf( ber, "t{", type );
			if ( cookie ) {
				ber_printf( ber, "O", cookie );
			}
			if ( refreshDeletes == 1 ) {
				ber_printf( ber, "b", refreshDeletes );
			}
			ber_printf( ber, "[W]", syncUUIDs );
			ber_printf( ber, "N}" );
			break;
		default:
			Debug( LDAP_DEBUG_TRACE,
				"syncprov_sendinfo: invalid syncinfo type (%d)\n",
				type, 0, 0 );
			return LDAP_OTHER;
		}
	}

	ret = ber_flatten2( ber, &rspdata, 0 );

	if ( ret < 0 ) {
		Debug( LDAP_DEBUG_TRACE,
			"syncprov_sendinfo: ber_flatten2 failed\n",
			0, 0, 0 );
		send_ldap_error( op, rs, LDAP_OTHER, "internal error" );
		return ret;
	}

	rs->sr_rspoid = LDAP_SYNC_INFO;
	rs->sr_rspdata = &rspdata;
	send_ldap_intermediate( op, rs );
	rs->sr_rspdata = NULL;
	ber_free_buf( ber );

	return LDAP_SUCCESS;
}

/* Find a modtarget in an AVL tree */
static int
sp_avl_cmp( const void *c1, const void *c2 )
{
	const modtarget *m1, *m2;
	int rc;

	m1 = c1; m2 = c2;
	rc = m1->mt_op->o_req_ndn.bv_len - m2->mt_op->o_req_ndn.bv_len;

	if ( rc ) return rc;
	return ber_bvcmp( &m1->mt_op->o_req_ndn, &m2->mt_op->o_req_ndn );
}

/* syncprov_findbase:
 *   finds the true DN of the base of a search (with alias dereferencing) and
 * checks to make sure the base entry doesn't get replaced with a different
 * entry (e.g., swapping trees via ModDN, or retargeting an alias). If a
 * change is detected, any persistent search on this base must be terminated /
 * reloaded.
 *   On the first call, we just save the DN and entryID. On subsequent calls
 * we compare the DN and entryID with the saved values.
 */
static int
findbase_cb( Operation *op, SlapReply *rs )
{
	slap_callback *sc = op->o_callback;

	if ( rs->sr_type == REP_SEARCH && rs->sr_err == LDAP_SUCCESS ) {
		fbase_cookie *fc = sc->sc_private;

		/* If no entryID, we're looking for the first time.
		 * Just store whatever we got.
		 */
		if ( fc->fss->s_eid == NOID ) {
			fc->fbase = 2;
			fc->fss->s_eid = rs->sr_entry->e_id;
			ber_dupbv( &fc->fss->s_base, &rs->sr_entry->e_nname );

		} else if ( rs->sr_entry->e_id == fc->fss->s_eid &&
			dn_match( &rs->sr_entry->e_nname, &fc->fss->s_base )) {

		/* OK, the DN is the same and the entryID is the same. */
			fc->fbase = 1;
		}
	}
	if ( rs->sr_err != LDAP_SUCCESS ) {
		Debug( LDAP_DEBUG_ANY, "findbase failed! %d\n", rs->sr_err,0,0 );
	}
	return LDAP_SUCCESS;
}

static Filter generic_filter = { LDAP_FILTER_PRESENT, { 0 }, NULL };
static struct berval generic_filterstr = BER_BVC("(objectclass=*)");

static int
syncprov_findbase( Operation *op, fbase_cookie *fc )
{
	opcookie *opc = op->o_callback->sc_private;
	slap_overinst *on = opc->son;

	/* Use basic parameters from syncrepl search, but use
	 * current op's threadctx / tmpmemctx
	 */
	ldap_pvt_thread_mutex_lock( &fc->fss->s_mutex );
	if ( fc->fss->s_flags & PS_FIND_BASE ) {
		slap_callback cb = {0};
		Operation fop;
		SlapReply frs = { REP_RESULT };
		int rc;

		fc->fss->s_flags ^= PS_FIND_BASE;
		ldap_pvt_thread_mutex_unlock( &fc->fss->s_mutex );

		fop = *fc->fss->s_op;

		fop.o_hdr = op->o_hdr;
		fop.o_bd = op->o_bd;
		fop.o_time = op->o_time;
		fop.o_tincr = op->o_tincr;

		cb.sc_response = findbase_cb;
		cb.sc_private = fc;

		fop.o_sync_mode = 0;	/* turn off sync mode */
		fop.o_managedsait = SLAP_CONTROL_CRITICAL;
		fop.o_callback = &cb;
		fop.o_tag = LDAP_REQ_SEARCH;
		fop.ors_scope = LDAP_SCOPE_BASE;
		fop.ors_limit = NULL;
		fop.ors_slimit = 1;
		fop.ors_tlimit = SLAP_NO_LIMIT;
		fop.ors_attrs = slap_anlist_no_attrs;
		fop.ors_attrsonly = 1;
		fop.ors_filter = &generic_filter;
		fop.ors_filterstr = generic_filterstr;

		fop.o_bd->bd_info = on->on_info->oi_orig;
		rc = fop.o_bd->be_search( &fop, &frs );
		fop.o_bd->bd_info = (BackendInfo *)on;
	} else {
		ldap_pvt_thread_mutex_unlock( &fc->fss->s_mutex );
		fc->fbase = 1;
	}

	/* After the first call, see if the fdn resides in the scope */
	if ( fc->fbase == 1 ) {
		switch ( fc->fss->s_op->ors_scope ) {
		case LDAP_SCOPE_BASE:
			fc->fscope = dn_match( fc->fdn, &fc->fss->s_base );
			break;
		case LDAP_SCOPE_ONELEVEL: {
			struct berval pdn;
			dnParent( fc->fdn, &pdn );
			fc->fscope = dn_match( &pdn, &fc->fss->s_base );
			break; }
		case LDAP_SCOPE_SUBTREE:
			fc->fscope = dnIsSuffix( fc->fdn, &fc->fss->s_base );
			break;
		case LDAP_SCOPE_SUBORDINATE:
			fc->fscope = dnIsSuffix( fc->fdn, &fc->fss->s_base ) &&
				!dn_match( fc->fdn, &fc->fss->s_base );
			break;
		}
	}

	if ( fc->fbase )
		return LDAP_SUCCESS;

	/* If entryID has changed, then the base of this search has
	 * changed. Invalidate the psearch.
	 */
	return LDAP_NO_SUCH_OBJECT;
}

/* syncprov_findcsn:
 *   This function has three different purposes, but they all use a search
 * that filters on entryCSN so they're combined here.
 * 1: at startup time, after a contextCSN has been read from the database,
 * we search for all entries with CSN >= contextCSN in case the contextCSN
 * was not checkpointed at the previous shutdown.
 *
 * 2: when the current contextCSN is known and we have a sync cookie, we search
 * for one entry with CSN = the cookie CSN. If not found, try <= cookie CSN.
 * If an entry is found, the cookie CSN is valid, otherwise it is stale.
 *
 * 3: during a refresh phase, we search for all entries with CSN <= the cookie
 * CSN, and generate Present records for them. We always collect this result
 * in SyncID sets, even if there's only one match.
 */