1 files changed, 652 insertions, 0 deletions

diff --git a/contrib/slapd-modules/adremap/adremap.c b/contrib/slapd-modules/adremap/adremap.c
new file mode 100644
index 0000000..5a7b8f1
--- /dev/null
+++ b/contrib/slapd-modules/adremap/adremap.c
@@ -0,0 +1,652 @@
+/* adremap.c - Case-folding and DN-value remapping for AD proxies */
+/* $OpenLDAP$ */
+/*
+ * Copyright 2015 Howard Chu <hyc@symas.com>.
+ * 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>.
+ */
+
+#include "portable.h"
+
+/*
+ * This file implements an overlay that performs two remapping functions
+ * to allow older POSIX clients to use Microsoft AD:
+ * 1: downcase the values of a configurable list of attributes
+ * 2: dereference some DN-valued attributes and convert to their simple names
+ *	   e.g. generate memberUid based on member
+ */
+
+#ifdef SLAPD_OVER_ADREMAP
+
+#include <ldap.h>
+#include "lutil.h"
+#include "slap.h"
+#include <ac/errno.h>
+#include <ac/time.h>
+#include <ac/string.h>
+#include <ac/ctype.h>
+#include "slap-config.h"
+
+typedef struct adremap_dnv {
+	struct adremap_dnv *ad_next;
+	AttributeDescription *ad_dnattr;	/* DN-valued attr to deref */
+	AttributeDescription *ad_deref;		/* target attr's value to retrieve */
+	AttributeDescription *ad_newattr;	/* New attr to collect new values */
+	ObjectClass *ad_group;		/* group objectclass on target */
+	ObjectClass *ad_mapgrp;		/* group objectclass to map */
+	ObjectClass *ad_refgrp;		/* objectclass of target DN */
+	struct berval ad_refbase;	/* base DN of target entries */
+} adremap_dnv;
+/* example: member uid memberUid */
+
+typedef struct adremap_case {
+	struct adremap_case *ac_next;
+	AttributeDescription *ac_attr;
+} adremap_case;
+
+/* Per-instance configuration information */
+typedef struct adremap_info {
+	adremap_case *ai_case;	/* attrs to downcase */
+	adremap_dnv *ai_dnv;	/* DN attrs to remap */
+} adremap_info;
+
+enum {
+	ADREMAP_CASE = 1,
+	ADREMAP_DNV
+};
+
+static ConfigDriver adremap_cf_case;
+static ConfigDriver adremap_cf_dnv;
+
+/* configuration attribute and objectclass */
+static ConfigTable adremapcfg[] = {
+	{ "adremap-downcase", "attrs", 2, 0, 0,
+	  ARG_MAGIC|ADREMAP_CASE, adremap_cf_case,
+	  "( OLcfgCtAt:6.1 "
+	  "NAME 'olcADremapDowncase' "
+	  "DESC 'List of attributes to casefold to lower case' "
+	  "EQUALITY caseIgnoreMatch "
+	  "SYNTAX OMsDirectoryString )", NULL, NULL },
+	{ "adremap-dnmap", "dnattr targetattr newattr remoteOC localOC targetOC baseDN", 8, 8, 0,
+	  ARG_MAGIC|ADREMAP_DNV, adremap_cf_dnv,
+	  "( OLcfgCtAt:6.2 "
+	  "NAME 'olcADremapDNmap' "
+	  "DESC 'DN attr to map, attr from target to use, attr to generate, objectclass of remote"
+	   " group, objectclass mapped group, objectclass of target entry, base DN of target entry' "
+	  "EQUALITY caseIgnoreMatch "
+	  "SYNTAX OMsDirectoryString )", NULL, NULL },
+	{ NULL, NULL, 0, 0, 0, ARG_IGNORED }
+};
+
+static ConfigOCs adremapocs[] = {
+	{ "( OLcfgCtOc:6.1 "
+	  "NAME 'olcADremapConfig' "
+	  "DESC 'AD remap configuration' "
+	  "SUP olcOverlayConfig "
+	  "MAY ( olcADremapDowncase $ olcADremapDNmap ) )",
+	  Cft_Overlay, adremapcfg, NULL, NULL },
+	{ NULL, 0, NULL }
+};
+
+static int
+adremap_cf_case(ConfigArgs *c)
+{
+	BackendDB *be = (BackendDB *)c->be;
+	slap_overinst *on = (slap_overinst *)c->bi;
+	adremap_info *ai = on->on_bi.bi_private;
+	adremap_case *ac, **a2;
+	int rc = ARG_BAD_CONF;
+
+	switch(c->op) {
+	case SLAP_CONFIG_EMIT:
+		for (ac = ai->ai_case; ac; ac=ac->ac_next) {
+			rc = value_add_one(&c->rvalue_vals, &ac->ac_attr->ad_cname);
+			if (rc) break;
+		}
+		break;
+	case LDAP_MOD_DELETE:
+		if (c->valx < 0) {
+			for (ac = ai->ai_case; ac; ac=ai->ai_case) {
+				ai->ai_case = ac->ac_next;
+				ch_free(ac);
+			}
+		} else {
+			int i;
+			for (i=0, a2 = &ai->ai_case; i<c->valx; i++, a2 = &(*a2)->ac_next);
+			ac = *a2;
+			*a2 = ac->ac_next;
+			ch_free(ac);
+		}
+		rc = 0;
+		break;
+	default: {
+		const char *text;
+		adremap_case ad;
+		ad.ac_attr = NULL;
+		rc = slap_str2ad(c->argv[1], &ad.ac_attr, &text);
+		if (rc) break;
+		for (a2 = &ai->ai_case; *a2; a2 = &(*a2)->ac_next);
+		ac = ch_malloc(sizeof(adremap_case));
+		ac->ac_next = NULL;
+		ac->ac_attr = ad.ac_attr;
+		*a2 = ac;
+		break;
+		}
+	}
+	return rc;
+}
+
+static int
+adremap_cf_dnv(ConfigArgs *c)
+{
+	BackendDB *be = (BackendDB *)c->be;
+	slap_overinst *on = (slap_overinst *)c->bi;
+	adremap_info *ai = on->on_bi.bi_private;
+	adremap_dnv *ad, **a2;
+	int rc = ARG_BAD_CONF;
+
+	switch(c->op) {
+	case SLAP_CONFIG_EMIT:
+		for (ad = ai->ai_dnv; ad; ad=ad->ad_next) {
+			char *ptr;
+			struct berval bv;
+			bv.bv_len = ad->ad_dnattr->ad_cname.bv_len + ad->ad_deref->ad_cname.bv_len + ad->ad_newattr->ad_cname.bv_len + 2;
+			bv.bv_len += ad->ad_group->soc_cname.bv_len + ad->ad_mapgrp->soc_cname.bv_len + ad->ad_refgrp->soc_cname.bv_len + 3;
+			bv.bv_len += ad->ad_refbase.bv_len + 3;
+			bv.bv_val = ch_malloc(bv.bv_len + 1);
+			ptr = lutil_strcopy(bv.bv_val, ad->ad_dnattr->ad_cname.bv_val);
+			*ptr++ = ' ';
+			ptr = lutil_strcopy(ptr, ad->ad_deref->ad_cname.bv_val);
+			*ptr++ = ' ';
+			ptr = lutil_strcopy(ptr, ad->ad_newattr->ad_cname.bv_val);
+			*ptr++ = ' ';
+			ptr = lutil_strcopy(ptr, ad->ad_group->soc_cname.bv_val);
+			*ptr++ = ' ';
+			ptr = lutil_strcopy(ptr, ad->ad_mapgrp->soc_cname.bv_val);
+			*ptr++ = ' ';
+			ptr = lutil_strcopy(ptr, ad->ad_refgrp->soc_cname.bv_val);
+			*ptr++ = ' ';
+			*ptr++ = '"';
+			ptr = lutil_strcopy(ptr, ad->ad_refbase.bv_val);
+			*ptr++ = '"';
+			*ptr = '\0';
+			ber_bvarray_add(&c->rvalue_vals, &bv);
+		}
+		if (ai->ai_dnv) rc = 0;
+		break;
+	case LDAP_MOD_DELETE:
+		if (c->valx < 0) {
+			for (ad = ai->ai_dnv; ad; ad=ai->ai_dnv) {
+				ai->ai_dnv = ad->ad_next;
+				ch_free(ad);
+			}
+		} else {
+			int i;
+			for (i=0, a2 = &ai->ai_dnv; i<c->valx; i++, a2 = &(*a2)->ad_next);
+			ad = *a2;
+			*a2 = ad->ad_next;
+			ch_free(ad);
+		}
+		rc = 0;
+		break;
+	default: {
+		const char *text;
+		adremap_dnv av = {0};
+		struct berval dn;
+		rc = slap_str2ad(c->argv[1], &av.ad_dnattr, &text);
+		if (rc) break;
+		if (av.ad_dnattr->ad_type->sat_syntax != slap_schema.si_syn_distinguishedName) {
+			rc = 1;
+			snprintf(c->cr_msg, sizeof(c->cr_msg), "<%s> not a DN-valued attribute",
+				c->argv[0]);
+			Debug(LDAP_DEBUG_ANY, "%s: %s(%s)\n", c->log, c->cr_msg, c->argv[1]);
+			break;
+		}
+		rc = slap_str2ad(c->argv[2], &av.ad_deref, &text);
+		if (rc) break;
+		rc = slap_str2ad(c->argv[3], &av.ad_newattr, &text);
+		if (rc) break;
+		av.ad_group = oc_find(c->argv[4]);
+		if (!av.ad_group) {
+			rc = 1;
+			break;
+		}
+		av.ad_mapgrp = oc_find(c->argv[5]);
+		if (!av.ad_mapgrp) {
+			rc = 1;
+			break;
+		}
+		av.ad_refgrp = oc_find(c->argv[6]);
+		if (!av.ad_refgrp) {
+			rc = 1;
+			break;
+		}
+		ber_str2bv(c->argv[7], 0, 0, &dn);
+		rc = dnNormalize(0, NULL, NULL, &dn, &av.ad_refbase, NULL);
+		if (rc) break;
+
+		for (a2 = &ai->ai_dnv; *a2; a2 = &(*a2)->ad_next);
+		ad = ch_malloc(sizeof(adremap_dnv));
+		ad->ad_next = NULL;
+		ad->ad_dnattr = av.ad_dnattr;
+		ad->ad_deref = av.ad_deref;
+		ad->ad_newattr = av.ad_newattr;
+		ad->ad_group = av.ad_group;
+		ad->ad_mapgrp = av.ad_mapgrp;
+		ad->ad_refgrp = av.ad_refgrp;
+		ad->ad_refbase = av.ad_refbase;
+		*a2 = ad;
+		break;
+		}
+	}
+	return rc;
+}
+
+typedef struct adremap_ctx {
+	slap_overinst *on;
+	AttributeName an;
+	AttributeDescription *ad;
+	int an_swap;
+} adremap_ctx;
+
+static int
+adremap_search_resp(
+	Operation *op,
+	SlapReply *rs
+)
+{
+	adremap_ctx *ctx = op->o_callback->sc_private;
+	slap_overinst *on = ctx->on;
+	adremap_info *ai = on->on_bi.bi_private;
+	adremap_case *ac;
+	adremap_dnv *ad;
+	Attribute *a;
+	Entry *e;
+
+	if (rs->sr_type != REP_SEARCH)
+		return SLAP_CB_CONTINUE;
+
+	/* we munged the attr list, restore it to original */
+	if (ctx->an_swap) {
+		int i;
+		ctx->an_swap = 0;
+		for (i=0; rs->sr_attrs[i].an_name.bv_val; i++) {
+			if (rs->sr_attrs[i].an_desc == ctx->ad) {
+				rs->sr_attrs[i] = ctx->an;
+				break;
+			}
+		}
+		/* Usually rs->sr_attrs is just op->ors_attrs, but
+		 * overlays like rwm may make a new copy. Fix both
+		 * if needed.
+		 */
+		if (op->ors_attrs != rs->sr_attrs) {
+			for (i=0; op->ors_attrs[i].an_name.bv_val; i++) {
+				if (op->ors_attrs[i].an_desc == ctx->ad) {
+					op->ors_attrs[i] = ctx->an;
+					break;
+				}
+			}
+		}
+	}
+	e = rs->sr_entry;
+	for (ac = ai->ai_case; ac; ac = ac->ac_next) {
+		a = attr_find(e->e_attrs, ac->ac_attr);
+		if (a) {
+			int i, j;
+			if (!(rs->sr_flags & REP_ENTRY_MODIFIABLE)) {
+				e = entry_dup(e);
+				rs_replace_entry(op, rs, on, e);
+				rs->sr_flags |= REP_ENTRY_MODIFIABLE|REP_ENTRY_MUSTBEFREED;
+				a = attr_find(e->e_attrs, ac->ac_attr);
+			}
+			for (i=0; i<a->a_numvals; i++) {
+				unsigned char *c = a->a_vals[i].bv_val;
+				for (j=0; j<a->a_vals[i].bv_len; j++)
+					if (isupper(c[j]))
+						c[j] = tolower(c[j]);
+			}
+		}
+	}
+	for (ad = ai->ai_dnv; ad; ad = ad->ad_next) {
+		a = attr_find(e->e_attrs, ad->ad_dnattr);
+		if (a) {
+			Entry *n;
+			Attribute *dr;
+			int i, rc;
+			if (!(rs->sr_flags & REP_ENTRY_MODIFIABLE)) {
+				e = entry_dup(e);
+				rs_replace_entry(op, rs, on, e);
+				rs->sr_flags |= REP_ENTRY_MODIFIABLE|REP_ENTRY_MUSTBEFREED;
+				a = attr_find(e->e_attrs, ad->ad_dnattr);
+			}
+			for (i=0; i<a->a_numvals; i++) {
+				struct berval dv;
+				dv = ad->ad_deref->ad_cname;
+					/* If the RDN uses the deref attr, just use it directly */
+				if (a->a_nvals[i].bv_val[dv.bv_len] == '=' &&
+					!memcmp(a->a_nvals[i].bv_val, dv.bv_val, dv.bv_len)) {
+					struct berval bv, nv;
+					char *ptr;
+					bv = a->a_vals[i];
+					nv = a->a_nvals[i];
+					bv.bv_val += dv.bv_len + 1;
+					ptr = strchr(bv.bv_val, ',');
+					if (ptr)
+						bv.bv_len = ptr - bv.bv_val;
+					else
+						bv.bv_len -= dv.bv_len+1;
+					nv.bv_val += dv.bv_len + 1;
+					ptr = strchr(nv.bv_val, ',');
+					if (ptr)
+						nv.bv_len = ptr - nv.bv_val;
+					else
+						nv.bv_len -= dv.bv_len+1;
+					attr_merge_one(e, ad->ad_newattr, &bv, &nv);
+				} else {
+					/* otherwise look up the deref attr */
+					n = NULL;
+					rc = be_entry_get_rw(op, &a->a_nvals[i], NULL, ad->ad_deref, 0, &n);
+					if (!rc && n) {
+						dr = attr_find(n->e_attrs, ad->ad_deref);
+						if (dr)
+							attr_merge_one(e, ad->ad_newattr, dr->a_vals, dr->a_nvals);
+						be_entry_release_r(op, n);
+					}
+				}
+			}
+		}
+	}
+	return SLAP_CB_CONTINUE;
+}
+
+static int adremap_refsearch(
+	Operation *op,
+	SlapReply *rs
+)
+{
+	if (rs->sr_type == REP_SEARCH) {
+		slap_callback *sc = op->o_callback;
+		struct berval *dn = sc->sc_private;
+		ber_dupbv_x(dn, &rs->sr_entry->e_nname, op->o_tmpmemctx);
+		return LDAP_SUCCESS;
+	}
+	return rs->sr_err;
+}
+
+static adremap_dnv *adremap_filter(
+	Operation *op,
+	adremap_info *ai
+)
+{
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	Filter *f = op->ors_filter, *fn = NULL;
+	adremap_dnv *ad = NULL;
+	struct berval bv;
+	int fextra = 0;
+
+	/* Do we need to munge the filter? First see if it's of
+	 * the form (objectClass=<mapgrp>)
+	 * or form (&(objectClass=<mapgrp>)...)
+	 * or form (&(&(objectClass=<mapgrp>)...)...)
+	 */
+	if (f->f_choice == LDAP_FILTER_AND && f->f_and) {
+		fextra = 1;
+		f = f->f_and;
+		fn = f->f_next;
+	}
+	if (f->f_choice == LDAP_FILTER_AND && f->f_and) {
+		fextra = 2;
+		f = f->f_and;
+	}
+	if (f->f_choice == LDAP_FILTER_EQUALITY &&
+		f->f_av_desc == slap_schema.si_ad_objectClass) {
+		struct berval bv = f->f_av_value;
+
+		for (ad = ai->ai_dnv; ad; ad = ad->ad_next) {
+			if (!ber_bvstrcasecmp( &bv, &ad->ad_mapgrp->soc_cname )) {
+			/* Now check to see if next element is (<newattr>=foo) */
+				Filter *fnew;
+				if (fn && fn->f_choice == LDAP_FILTER_EQUALITY &&
+					fn->f_av_desc == ad->ad_newattr) {
+					Filter fr[3];
+					AttributeAssertion aa[2] = {0};
+					Operation op2;
+					slap_callback cb = {0};
+					SlapReply rs = {REP_RESULT};
+					struct berval dn = BER_BVNULL;
+
+					/* It's a match, setup a search with filter
+					 * (&(objectclass=<refgrp>)(<deref>=foo))
+					 */
+					fr[0].f_choice = LDAP_FILTER_AND;
+					fr[0].f_and = &fr[1];
+					fr[0].f_next = NULL;
+
+					fr[1].f_choice = LDAP_FILTER_EQUALITY;
+					fr[1].f_ava = &aa[0];
+					fr[1].f_av_desc = slap_schema.si_ad_objectClass;
+					fr[1].f_av_value = ad->ad_refgrp->soc_cname;
+					fr[1].f_next = &fr[2];
+
+					fr[2].f_choice = LDAP_FILTER_EQUALITY;
+					fr[2].f_ava = &aa[1];
+					fr[2].f_av_desc = ad->ad_deref;
+					fr[2].f_av_value = fn->f_av_value;
+					fr[2].f_next = NULL;
+
+					/* Search with this filter to retrieve target DN */
+					op2 = *op;
+					op2.o_callback = &cb;
+					cb.sc_response = adremap_refsearch;
+					cb.sc_private = &dn;
+					op2.o_req_dn = ad->ad_refbase;
+					op2.o_req_ndn = ad->ad_refbase;
+					op2.ors_filter = fr;
+					filter2bv_x(op, fr, &op2.ors_filterstr);
+					op2.ors_deref = LDAP_DEREF_NEVER;
+					op2.ors_slimit = 1;
+					op2.ors_tlimit = SLAP_NO_LIMIT;
+					op2.ors_attrs = slap_anlist_no_attrs;
+					op2.ors_attrsonly = 1;
+					op2.o_no_schema_check = 1;
+					op2.o_bd->bd_info = (BackendInfo *)on->on_info;
+					op2.o_bd->be_search(&op2, &rs);
+					op2.o_bd->bd_info = (BackendInfo *)on;
+					op->o_tmpfree(op2.ors_filterstr.bv_val, op->o_tmpmemctx);
+
+					if (!dn.bv_len) {	/* no match was found */
+						ad = NULL;
+						break;
+					}
+
+					if (rs.sr_err) {	/* sizelimit exceeded, etc.: invalid name */
+						op->o_tmpfree(dn.bv_val, op->o_tmpmemctx);
+						ad = NULL;
+						break;
+					}
+
+					/* Build a new filter of form
+					 * (&(objectclass=<group>)(<dnattr>=foo-DN)...)
+					 */
+					f = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+					f->f_choice = LDAP_FILTER_AND;
+					fnew = f;
+					f->f_next = NULL;
+
+					f->f_and = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+					f = f->f_and;
+					f->f_choice = LDAP_FILTER_EQUALITY;
+					f->f_ava = op->o_tmpcalloc(1, sizeof(AttributeAssertion), op->o_tmpmemctx);
+					f->f_av_desc = slap_schema.si_ad_objectClass;
+					ber_dupbv_x(&f->f_av_value, &ad->ad_group->soc_cname, op->o_tmpmemctx);
+
+					f->f_next = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+					f = f->f_next;
+					f->f_choice = LDAP_FILTER_EQUALITY;
+					f->f_ava = op->o_tmpcalloc(1, sizeof(AttributeAssertion), op->o_tmpmemctx);
+					f->f_av_desc = ad->ad_dnattr;
+					f->f_av_value = dn;
+
+					f->f_next = fn->f_next;
+					fn->f_next = NULL;
+				} else {
+					/* Build a new filter of form
+					 * (objectclass=<group>)
+					 */
+					f->f_next = NULL;	/* disconnect old chain */
+
+					f = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+					f->f_choice = LDAP_FILTER_EQUALITY;
+					f->f_ava = op->o_tmpcalloc(1, sizeof(AttributeAssertion), op->o_tmpmemctx);
+					f->f_av_desc = slap_schema.si_ad_objectClass;
+					ber_dupbv_x(&f->f_av_value, &ad->ad_group->soc_cname, op->o_tmpmemctx);
+
+					/* If there was a wrapping (&), attach it. */
+					if (fextra) {
+						fnew = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+						fnew->f_choice = LDAP_FILTER_AND;
+						fnew->f_and = f;
+						fnew->f_next = NULL;
+						f->f_next = fn;
+					} else {
+						fnew = f;
+						f->f_next = NULL;
+					}
+				}
+				if (fextra > 1) {
+					f = op->o_tmpalloc(sizeof(Filter), op->o_tmpmemctx);
+					f->f_choice = LDAP_FILTER_AND;
+					f->f_and = fnew->f_and;
+					f->f_next = f->f_and->f_next;
+					f->f_and->f_next = op->ors_filter->f_and->f_and->f_next;
+					op->ors_filter->f_and->f_and->f_next = NULL;
+					fnew->f_and = f;
+				}
+				filter_free_x(op, op->ors_filter, 1);
+				op->o_tmpfree(op->ors_filterstr.bv_val, op->o_tmpmemctx);
+				op->ors_filter = fnew;
+				filter2bv_x(op, op->ors_filter, &op->ors_filterstr);
+				break;
+			}
+		}
+	}
+	return ad;
+}
+
+static int
+adremap_search(
+	Operation *op,
+	SlapReply *rs
+)
+{
+	slap_overinst *on = (slap_overinst *)op->o_bd->bd_info;
+	adremap_info *ai = (adremap_info *) on->on_bi.bi_private;
+	adremap_ctx *ctx;
+	adremap_dnv *ad = NULL;
+	slap_callback *cb;
+
+	/* Is this our own internal search? Ignore it */
+	if (op->o_no_schema_check)
+		return SLAP_CB_CONTINUE;
+
+	if (ai->ai_dnv)
+		/* check for filter match, fallthru if none */
+		ad = adremap_filter(op, ai);
+
+	cb = op->o_tmpcalloc(1, sizeof(slap_callback)+sizeof(adremap_ctx), op->o_tmpmemctx);
+	cb->sc_response = adremap_search_resp;
+	cb->sc_private = cb+1;
+	cb->sc_next = op->o_callback;
+	op->o_callback = cb;
+	ctx = cb->sc_private;
+	ctx->on = on;
+	if (ad && op->ors_attrs) {	/* see if we need to remap a search attr */
+		int i;
+		for (i=0; op->ors_attrs[i].an_name.bv_val; i++) {
+			if (op->ors_attrs[i].an_desc == ad->ad_newattr) {
+				ctx->an_swap = 1;
+				ctx->ad = ad->ad_dnattr;
+				ctx->an = op->ors_attrs[i];
+				op->ors_attrs[i].an_desc = ad->ad_dnattr;
+				op->ors_attrs[i].an_name = ad->ad_dnattr->ad_cname;
+				break;
+			}
+		}
+	}
+	return SLAP_CB_CONTINUE;
+}
+
+static int
+adremap_db_init(
+	BackendDB *be,
+	ConfigReply *cr
+)
+{
+	slap_overinst *on = (slap_overinst *) be->bd_info;
+
+	/* initialize private structure to store configuration */
+	on->on_bi.bi_private = ch_calloc( 1, sizeof(adremap_info) );
+
+	return 0;
+}
+
+static int
+adremap_db_destroy(
+	BackendDB *be,
+	ConfigReply *cr
+)
+{
+	slap_overinst *on = (slap_overinst *) be->bd_info;
+	adremap_info *ai = (adremap_info *) on->on_bi.bi_private;
+	adremap_case *ac;
+	adremap_dnv *ad;
+
+	/* free config */
+	for (ac = ai->ai_case; ac; ac = ai->ai_case) {
+		ai->ai_case = ac->ac_next;
+		ch_free(ac);
+	}
+	for (ad = ai->ai_dnv; ad; ad = ai->ai_dnv) {
+		ai->ai_dnv = ad->ad_next;
+		ch_free(ad);
+	}
+	free( ai );
+
+	return 0;
+}
+
+static slap_overinst adremap;
+
+int adremap_initialize()
+{
+	int i, code;
+
+	adremap.on_bi.bi_type = "adremap";
+	adremap.on_bi.bi_flags = SLAPO_BFLAG_SINGLE;
+	adremap.on_bi.bi_db_init = adremap_db_init;
+	adremap.on_bi.bi_db_destroy = adremap_db_destroy;
+	adremap.on_bi.bi_op_search = adremap_search;
+
+	/* register configuration directives */
+	adremap.on_bi.bi_cf_ocs = adremapocs;
+	code = config_register_schema( adremapcfg, adremapocs );
+	if ( code ) return code;
+
+	return overlay_register( &adremap );
+}
+
+#if SLAPD_OVER_ADREMAP == SLAPD_MOD_DYNAMIC
+int init_module(int argc, char *argv[]) {
+	return adremap_initialize();
+}
+#endif
+
+#endif	/* defined(SLAPD_OVER_ADREMAP) */