Adding upstream version 3.2.1+dfsg.upstream/3.2.1+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1605 insertions, 0 deletions

diff --git a/src/modules/rlm_ldap/ldap.c b/src/modules/rlm_ldap/ldap.c
new file mode 100644
index 0000000..adabe33
--- /dev/null
+++ b/src/modules/rlm_ldap/ldap.c
@@ -0,0 +1,1605 @@
+/*
+ *   This program is is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or (at
+ *   your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+/**
+ * $Id$
+ * @file ldap.c
+ * @brief LDAP module library functions.
+ *
+ * @author Arran Cudbard-Bell <a.cudbardb@freeradius.org>
+ * @copyright 2015 Arran Cudbard-Bell <a.cudbardb@freeradius.org>
+ * @copyright 2013-2015 Network RADIUS SARL <info@networkradius.com>
+ * @copyright 2013-2015 The FreeRADIUS Server Project.
+ */
+#include <freeradius-devel/radiusd.h>
+#include <freeradius-devel/modules.h>
+#include <freeradius-devel/rad_assert.h>
+
+#include <stdarg.h>
+#include <ctype.h>
+
+#include "ldap.h"
+
+/** Converts "bad" strings into ones which are safe for LDAP
+ *
+ * @note RFC 4515 says filter strings can only use the @verbatim \<hex><hex> @endverbatim
+ *	format, whereas RFC 4514 indicates that some chars in DNs, may be escaped simply
+ *	with a backslash. For simplicity, we always use the hex escape sequences.
+ *	In other areas where we're doing DN comparison, the DNs need to be normalised first
+ *	so that they both use only hex escape sequences.
+ *
+ * @note This is a callback for xlat operations.
+ *
+ * Will escape any characters in input strings that would cause the string to be interpreted
+ * as part of a DN and or filter. Escape sequence is @verbatim \<hex><hex> @endverbatim.
+ *
+ * @param request The current request.
+ * @param out Pointer to output buffer.
+ * @param outlen Size of the output buffer.
+ * @param in Raw unescaped string.
+ * @param arg Any additional arguments (unused).
+ */
+size_t rlm_ldap_escape_func(UNUSED REQUEST *request, char *out, size_t outlen, char const *in, UNUSED void *arg)
+{
+	static char const encode[] = ",+\"\\<>;*=()";
+	static char const hextab[] = "0123456789abcdef";
+	size_t left = outlen;
+
+	if (*in && ((*in == ' ') || (*in == '#'))) goto encode;
+
+	while (*in) {
+		/*
+		 *	Encode unsafe characters.
+		 */
+		if (memchr(encode, *in, sizeof(encode) - 1)) {
+		encode:
+			/*
+			 *	Only 3 or less bytes available.
+			 */
+			if (left <= 3) break;
+
+			*out++ = '\\';
+			*out++ = hextab[(*in >> 4) & 0x0f];
+			*out++ = hextab[*in & 0x0f];
+			in++;
+			left -= 3;
+
+			continue;
+		}
+
+		if (left <= 1) break;
+
+		/*
+		 *	Doesn't need encoding
+		 */
+		*out++ = *in++;
+		left--;
+	}
+
+	*out = '\0';
+
+	return outlen - left;
+}
+
+/** Check whether a string looks like a DN
+ *
+ * @param[in] in Str to check.
+ * @param[in] inlen Length of string to check.
+ * @return
+ *	- true if string looks like a DN.
+ *	- false if string does not look like DN.
+ */
+bool rlm_ldap_is_dn(char const *in, size_t inlen)
+{
+	char const *p;
+
+	char want = '=';
+	bool too_soon = true;
+	int comp = 1;
+
+	for (p = in; inlen > 0; p++, inlen--) {
+		if (p[0] == '\\') {
+			char c;
+
+			too_soon = false;
+
+			/*
+			 *	Invalid escape sequence, not a DN
+			 */
+			if (inlen < 2) return false;
+
+			/*
+			 *	Double backslash, consume two chars
+			 */
+			if (p[1] == '\\') {
+				inlen--;
+				p++;
+				continue;
+			}
+
+			/*
+			 *	Special, consume two chars
+			 */
+			switch (p[1]) {
+			case ' ':
+			case '#':
+			case '=':
+			case '"':
+			case '+':
+			case ',':
+			case ';':
+			case '<':
+			case '>':
+			case '\'':
+				inlen -= 1;
+				p += 1;
+				continue;
+
+			default:
+				break;
+			}
+
+			/*
+			 *	Invalid escape sequence, not a DN
+			 */
+			if (inlen < 3) return false;
+
+			/*
+			 *	Hex encoding, consume three chars
+			 */
+			if (fr_hex2bin((uint8_t *) &c, 1, p + 1, 2) == 1) {
+				inlen -= 2;
+				p += 2;
+				continue;
+			}
+
+			/*
+			 *	Invalid escape sequence, not a DN
+			 */
+			return false;
+		}
+
+		switch (*p) {
+		case '=':
+			if (too_soon || (*p != want)) return false;	/* Too soon after last , or = */
+			want = ',';
+			too_soon = true;
+			break;
+
+		case ',':
+			if (too_soon || (*p != want)) return false;	/* Too soon after last , or = */
+			want = '=';
+			too_soon = true;
+			comp++;
+			break;
+
+		default:
+			too_soon = false;
+			break;
+		}
+	}
+
+	/*
+	 *	If the string ended with , or =, or the number
+	 *	of components was less than 2
+	 *
+	 *	i.e. we don't have <attr>=<val>,<attr>=<val>
+	 */
+	if (too_soon || (comp < 2)) return false;
+
+	return true;
+}
+
+/** Convert a berval to a talloced string
+ *
+ * The ldap_get_values function is deprecated, and ldap_get_values_len
+ * does not guarantee the berval buffers it returns are \0 terminated.
+ *
+ * For some cases this is fine, for others we require a \0 terminated
+ * buffer (feeding DNs back into libldap for example).
+ *
+ * @param ctx to allocate in.
+ * @param in Berval to copy.
+ * @return \0 terminated buffer containing in->bv_val.
+ */
+char *rlm_ldap_berval_to_string(TALLOC_CTX *ctx, struct berval const *in)
+{
+	char *out;
+
+	out = talloc_array(ctx, char, in->bv_len + 1);
+	if (!out) return NULL;
+
+	memcpy(out, in->bv_val, in->bv_len);
+	out[in->bv_len] = '\0';
+
+	return out;
+}
+
+/** Normalise escape sequences in a DN
+ *
+ * Characters in a DN can either be escaped as
+ * @verbatim \<hex><hex> @endverbatim or @verbatim \<special> @endverbatim
+ *
+ * The LDAP directory chooses how characters are escaped, which can make
+ * local comparisons of DNs difficult.
+ *
+ * Here we search for hex sequences that match special chars, and convert
+ * them to the @verbatim \<special> @endverbatim form.
+ *
+ * @note the resulting output string will only ever be shorter than the
+ *       input, so it's fine to use the same buffer for both out and in.
+ *
+ * @param out Where to write the normalised DN.
+ * @param in The input DN.
+ * @return The number of bytes written to out.
+ */
+size_t rlm_ldap_normalise_dn(char *out, char const *in)
+{
+	char const *p;
+	char *o = out;
+
+	for (p = in; *p != '\0'; p++) {
+		if (p[0] == '\\') {
+			char c;
+
+			/*
+			 *	Double backslashes get processed specially
+			 */
+			if (p[1] == '\\') {
+				p += 1;
+				*o++ = p[0];
+				*o++ = p[1];
+				continue;
+			}
+
+			/*
+			 *	Hex encodings that have an alternative
+			 *	special encoding, get rewritten to the
+			 *	special encoding.
+			 */
+			if (fr_hex2bin((uint8_t *) &c, 1, p + 1, 2) == 1) {
+				switch (c) {
+				case ' ':
+				case '#':
+				case '=':
+				case '"':
+				case '+':
+				case ',':
+				case ';':
+				case '<':
+				case '>':
+				case '\'':
+					*o++ = '\\';
+					*o++ = c;
+					p += 2;
+					continue;
+
+				default:
+					break;
+				}
+			}
+		}
+		*o++ = *p;
+	}
+	*o = '\0';
+
+	return o - out;
+}
+
+/** Find the place at which the two DN strings diverge
+ *
+ * Returns the length of the non matching string in full.
+ *
+ * @param full DN.
+ * @param part Partial DN as returned by ldap_parse_result.
+ * @return
+ *	- Length of the portion of full which wasn't matched
+ *	- -1 on failure.
+ */
+static size_t rlm_ldap_common_dn(char const *full, char const *part)
+{
+	size_t f_len, p_len, i;
+
+	if (!full) {
+		return -1;
+	}
+
+	f_len = strlen(full);
+
+	if (!part) {
+		return -1;
+	}
+
+	p_len = strlen(part);
+	if (!p_len) {
+		return f_len;
+	}
+
+	if ((f_len < p_len) || !f_len) {
+		return -1;
+	}
+
+	for (i = 0; i < p_len; i++) {
+		if (part[p_len - i] != full[f_len - i]) {
+			return -1;
+		}
+	}
+
+	return f_len - p_len;
+}
+
+/** Combine and expand filters
+ *
+ * @param request Current request.
+ * @param out Where to write the expanded string.
+ * @param outlen Length of output buffer.
+ * @param sub Array of subfilters (may contain NULLs).
+ * @param sublen Number of potential subfilters in array.
+ * @return length of expanded data.
+ */
+ssize_t rlm_ldap_xlat_filter(REQUEST *request, char const **sub, size_t sublen, char *out, size_t outlen)
+{
+	char buffer[LDAP_MAX_FILTER_STR_LEN + 1];
+	char const *in = NULL;
+	char *p = buffer;
+
+	ssize_t len = 0;
+
+	unsigned int i;
+	int cnt = 0;
+
+	/*
+	 *	Figure out how many filter elements we need to integrate
+	 */
+	for (i = 0; i < sublen; i++) {
+		if (sub[i] && *sub[i]) {
+			in = sub[i];
+			cnt++;
+		}
+	}
+
+	if (!cnt) {
+		out[0] = '\0';
+		return 0;
+	}
+
+	if (cnt > 1) {
+		if (outlen < 3) {
+			goto oob;
+		}
+
+		p[len++] = '(';
+		p[len++] = '&';
+
+		for (i = 0; i < sublen; i++) {
+			if (sub[i] && (*sub[i] != '\0')) {
+				len += strlcpy(p + len, sub[i], outlen - len);
+
+				if ((size_t) len >= outlen) {
+					oob:
+					REDEBUG("Out of buffer space creating filter");
+
+					return -1;
+				}
+			}
+		}
+
+		if ((outlen - len) < 2) {
+			goto oob;
+		}
+
+		p[len++] = ')';
+		p[len] = '\0';
+
+		in = buffer;
+	}
+
+	len = radius_xlat(out, outlen, request, in, rlm_ldap_escape_func, NULL);
+	if (len < 0) {
+		REDEBUG("Failed creating filter");
+
+		return -1;
+	}
+
+	return len;
+}
+
+/** Return the error string associated with a handle
+ *
+ * @param conn to retrieve error from.
+ * @return error string.
+ */
+char const *rlm_ldap_error_str(ldap_handle_t const *conn)
+{
+	int lib_errno;
+	ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &lib_errno);
+	if (lib_errno == LDAP_SUCCESS) {
+		return "unknown";
+	}
+
+	return ldap_err2string(lib_errno);
+}
+
+/** Parse response from LDAP server dealing with any errors
+ *
+ * Should be called after an LDAP operation. Will check result of operation and if it was successful, then attempt
+ * to retrieve and parse the result.
+ *
+ * Will also produce extended error output including any messages the server sent, and information about partial
+ * DN matches.
+ *
+ * @param[in] inst of LDAP module.
+ * @param[in] conn Current connection.
+ * @param[in] msgid returned from last operation. May be -1 if no result processing is required.
+ * @param[in] dn Last search or bind DN.
+ * @param[out] result Where to write result, if NULL result will be freed.
+ * @param[out] error Where to write the error string, may be NULL, must not be freed.
+ * @param[out] extra Where to write additional error string to, may be NULL (faster) or must be freed
+ *	(with talloc_free).
+ * @return One of the LDAP_PROC_* (#ldap_rcode_t) values.
+ */
+ldap_rcode_t rlm_ldap_result(rlm_ldap_t const *inst, ldap_handle_t const *conn, int msgid, char const *dn,
+			     LDAPMessage **result, char const **error, char **extra)
+{
+	ldap_rcode_t status = LDAP_PROC_SUCCESS;
+
+	int lib_errno = LDAP_SUCCESS;	// errno returned by the library.
+	int srv_errno = LDAP_SUCCESS;	// errno in the result message.
+
+	char *part_dn = NULL;		// Partial DN match.
+	char *our_err = NULL;		// Our extended error message.
+	char *srv_err = NULL;		// Server's extended error message.
+	char *p, *a;
+
+	bool freeit = false;		// Whether the message should be freed after being processed.
+	int len;
+
+	struct timeval tv;		// Holds timeout values.
+
+	LDAPMessage *tmp_msg = NULL;	// Temporary message pointer storage if we weren't provided with one.
+
+	char const *tmp_err;		// Temporary error pointer storage if we weren't provided with one.
+
+	if (!error) error = &tmp_err;
+	*error = NULL;
+
+	if (extra) *extra = NULL;
+	if (result) *result = NULL;
+
+	/*
+	 *	We always need the result, but our caller may not
+	 */
+	if (!result) {
+		result = &tmp_msg;
+		freeit = true;
+	}
+
+	/*
+	 *	Check if there was an error sending the request
+	 */
+	ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &lib_errno);
+	if (lib_errno != LDAP_SUCCESS) goto process_error;
+	if (msgid < 0) return LDAP_SUCCESS;	/* No msgid and no error, return now */
+
+	memset(&tv, 0, sizeof(tv));
+	tv.tv_sec = inst->res_timeout;
+
+	/*
+	 *	Now retrieve the result and check for errors
+	 *	ldap_result returns -1 on failure, and 0 on timeout
+	 */
+	lib_errno = ldap_result(conn->handle, msgid, 1, &tv, result);
+	if (lib_errno == 0) {
+		lib_errno = LDAP_TIMEOUT;
+
+		goto process_error;
+	}
+
+	if (lib_errno == -1) {
+		ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &lib_errno);
+
+		goto process_error;
+	}
+
+	/*
+	 *	Parse the result and check for errors sent by the server
+	 */
+	lib_errno = ldap_parse_result(conn->handle, *result,
+				      &srv_errno,
+				      extra ? &part_dn : NULL,
+				      extra ? &srv_err : NULL,
+				      NULL, NULL, freeit);
+	if (freeit) *result = NULL;
+
+	if (lib_errno != LDAP_SUCCESS) {
+		ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &lib_errno);
+		goto process_error;
+	}
+
+process_error:
+	if ((lib_errno == LDAP_SUCCESS) && (srv_errno != LDAP_SUCCESS)) {
+		lib_errno = srv_errno;
+	} else if ((lib_errno != LDAP_SUCCESS) && (srv_errno == LDAP_SUCCESS)) {
+		srv_errno = lib_errno;
+	}
+
+	switch (lib_errno) {
+	case LDAP_SUCCESS:
+		*error = "Success";
+		break;
+
+	case LDAP_SASL_BIND_IN_PROGRESS:
+		*error = "Continuing";
+		status = LDAP_PROC_CONTINUE;
+		break;
+
+	case LDAP_NO_SUCH_OBJECT:
+		*error = "The specified DN wasn't found";
+		status = LDAP_PROC_BAD_DN;
+
+		if (!extra) break;
+
+		/*
+		 *	Build our own internal diagnostic string
+		 */
+		len = rlm_ldap_common_dn(dn, part_dn);
+		if (len < 0) break;
+
+		our_err = talloc_typed_asprintf(conn, "Match stopped here: [%.*s]%s", len, dn, part_dn ? part_dn : "");
+		goto error_string;
+
+	case LDAP_INSUFFICIENT_ACCESS:
+		*error = "Insufficient access. Check the identity and password configuration directives";
+		status = LDAP_PROC_NOT_PERMITTED;
+		break;
+
+	case LDAP_UNWILLING_TO_PERFORM:
+		*error = "Server was unwilling to perform";
+		status = LDAP_PROC_NOT_PERMITTED;
+		break;
+
+	case LDAP_FILTER_ERROR:
+		*error = "Bad search filter";
+		status = LDAP_PROC_ERROR;
+		break;
+
+	case LDAP_TIMEOUT:
+		*error = "Timed out while waiting for server to respond";
+		goto timeout;
+
+	case LDAP_TIMELIMIT_EXCEEDED:
+		*error = "Time limit exceeded";
+	timeout:
+		exec_trigger(NULL, inst->cs, "modules.ldap.timeout", true);
+		/* FALL-THROUGH */
+
+	case LDAP_BUSY:
+	case LDAP_UNAVAILABLE:
+	case LDAP_SERVER_DOWN:
+		status = LDAP_PROC_RETRY;
+		goto error_string;
+
+	case LDAP_INVALID_CREDENTIALS:
+	case LDAP_CONSTRAINT_VIOLATION:
+		status = LDAP_PROC_REJECT;
+		goto error_string;
+
+	case LDAP_OPERATIONS_ERROR:
+		if (inst->chase_referrals) {
+			*error = "Operations error with LDAP database.  Please see the LDAP server configuration / documentation for more information.";
+		} else {
+			*error = "Please set 'chase_referrals=yes' and 'rebind=yes'. See the ldap module configuration "
+				"for details.";
+		}
+
+		/* FALL-THROUGH */
+	default:
+		status = LDAP_PROC_ERROR;
+
+	error_string:
+		if (!*error) *error = ldap_err2string(lib_errno);
+
+		if (!extra || ((lib_errno == srv_errno) && !our_err && !srv_err)) break;
+
+		/*
+		 *	Output the error codes from the library and server
+		 */
+		p = talloc_zero_array(conn, char, 1);
+		if (!p) break;
+
+		if (lib_errno != srv_errno) {
+			a = talloc_asprintf_append(p, "LDAP lib error: %s (%u), srv error: %s (%u). ",
+						   ldap_err2string(lib_errno), lib_errno,
+						   ldap_err2string(srv_errno), srv_errno);
+			if (!a) {
+				talloc_free(p);
+				break;
+			}
+
+			p = a;
+		}
+
+		if (our_err) {
+			a = talloc_asprintf_append_buffer(p, "%s. ", our_err);
+			if (!a) {
+				talloc_free(p);
+				break;
+			}
+
+			p = a;
+		}
+
+		if (srv_err) {
+			a = talloc_asprintf_append_buffer(p, "Server said: %s. ", srv_err);
+			if (!a) {
+				talloc_free(p);
+				break;
+			}
+
+			p = a;
+		}
+
+		*extra = p;
+
+		break;
+	}
+
+	/*
+	 *	Cleanup memory
+	 */
+	if (srv_err) ldap_memfree(srv_err);
+	if (part_dn) ldap_memfree(part_dn);
+
+	talloc_free(our_err);
+
+	if ((status < 0) && *result) {
+		ldap_msgfree(*result);
+		*result = NULL;
+	}
+
+	return status;
+}
+
+/** Bind to the LDAP directory as a user
+ *
+ * Performs a simple bind to the LDAP directory, and handles any errors that occur.
+ *
+ * @param[in] inst rlm_ldap configuration.
+ * @param[in] request Current request, this may be NULL, in which case all debug logging is done with radlog.
+ * @param[in,out] pconn to use. May change as this function calls functions which auto re-connect.
+ * @param[in] dn of the user, may be NULL to bind anonymously.
+ * @param[in] password of the user, may be NULL if no password is specified.
+ * @param[in] sasl mechanism to use for bind, and additional parameters.
+ * @param[in] retry if the server is down.
+ * @return One of the LDAP_PROC_* (#ldap_rcode_t) values.
+ */
+ldap_rcode_t rlm_ldap_bind(rlm_ldap_t const *inst, REQUEST *request, ldap_handle_t **pconn, char const *dn,
+			   char const *password, ldap_sasl *sasl, bool retry)
+{
+	ldap_rcode_t		status = LDAP_PROC_ERROR;
+
+	int			msgid = -1;
+
+	char const		*error = NULL;
+	char 			*extra = NULL;
+
+	int 			i, num;
+
+	rad_assert(*pconn && (*pconn)->handle);
+	rad_assert(!retry || inst->pool);
+
+#ifndef WITH_SASL
+	if (sasl && sasl->mech) {
+		REDEBUG("Server is built without SASL, but is being asked to do SASL.");
+		return status;
+	}
+#endif
+
+	/*
+	 *	Bind as anonymous user
+	 */
+	if (!dn) dn = "";
+
+	/*
+	 *	For sanity, for when no connections are viable,
+	 *	and we can't make a new one.
+	 */
+	num = retry ? fr_connection_pool_get_num(inst->pool) : 0;
+	for (i = num; i >= 0; i--) {
+#ifdef WITH_SASL
+		if (sasl && sasl->mech) {
+			status = rlm_ldap_sasl_interactive(inst, request, *pconn, dn, password, sasl,
+							   &error, &extra);
+		} else
+#endif
+		{
+			msgid = ldap_bind((*pconn)->handle, dn, password, LDAP_AUTH_SIMPLE);
+
+			/* We got a valid message ID */
+			if (msgid >= 0) {
+				if (request) {
+					RDEBUG2("Waiting for bind result...");
+				} else {
+					DEBUG2("rlm_ldap (%s): Waiting for bind result...", inst->name);
+				}
+			}
+
+			status = rlm_ldap_result(inst, *pconn, msgid, dn, NULL, &error, &extra);
+		}
+
+		switch (status) {
+		case LDAP_PROC_SUCCESS:
+			LDAP_DBG_REQ("Bind successful");
+			break;
+
+		case LDAP_PROC_NOT_PERMITTED:
+			LDAP_ERR_REQ("Bind was not permitted: %s", error);
+			LDAP_EXT_REQ();
+
+			break;
+
+		case LDAP_PROC_REJECT:
+			LDAP_ERR_REQ("Bind credentials incorrect: %s", error);
+			LDAP_EXT_REQ();
+
+			break;
+
+		case LDAP_PROC_RETRY:
+			if (retry) {
+				*pconn = fr_connection_reconnect(inst->pool, *pconn);
+				if (*pconn) {
+					LDAP_DBGW_REQ("Bind with %s to %s failed: %s. Got new socket, retrying...",
+						      *dn ? dn : "(anonymous)", inst->server, error);
+
+					talloc_free(extra); /* don't leak debug info */
+
+					continue;
+				}
+			};
+			status = LDAP_PROC_ERROR;
+
+			/*
+			 *	Were not allowed to retry, or there are no more
+			 *	sockets, treat this as a hard failure.
+			 */
+			/* FALL-THROUGH */
+		default:
+			LDAP_ERR_REQ("Bind with %s to %s failed: %s", *dn ? dn : "(anonymous)",
+				     inst->server, error);
+			LDAP_EXT_REQ();
+
+			break;
+		}
+
+		break;
+	}
+
+	if (retry && (i < 0)) {
+		LDAP_ERR_REQ("Hit reconnection limit");
+		status = LDAP_PROC_ERROR;
+	}
+
+	talloc_free(extra);
+
+	return status; /* caller closes the connection */
+}
+
+/** Search for something in the LDAP directory
+ *
+ * Binds as the administrative user and performs a search, dealing with any errors.
+ *
+ * @param[out] result Where to store the result. Must be freed with ldap_msgfree if LDAP_PROC_SUCCESS is returned.
+ *	May be NULL in which case result will be automatically freed after use.
+ * @param[in] inst rlm_ldap configuration.
+ * @param[in] request Current request.
+ * @param[in,out] pconn to use. May change as this function calls functions which auto re-connect.
+ * @param[in] dn to use as base for the search.
+ * @param[in] scope to use (LDAP_SCOPE_BASE, LDAP_SCOPE_ONE, LDAP_SCOPE_SUB).
+ * @param[in] filter to use, should be pre-escaped.
+ * @param[in] attrs to retrieve.
+ * @param[in] serverctrls Search controls to pass to the server.  May be NULL.
+ * @param[in] clientctrls Search controls for ldap_search.  May be NULL.
+ * @return One of the LDAP_PROC_* (#ldap_rcode_t) values.
+ */
+ldap_rcode_t rlm_ldap_search(LDAPMessage **result, rlm_ldap_t const *inst, REQUEST *request,
+			     ldap_handle_t **pconn,
+			     char const *dn, int scope, char const *filter, char const * const *attrs,
+			     LDAPControl **serverctrls, LDAPControl **clientctrls)
+{
+	ldap_rcode_t	status = LDAP_PROC_ERROR;
+	LDAPMessage	*our_result = NULL;
+
+	int		msgid;		// Message id returned by
+					// ldap_search_ext.
+
+	int		count = 0;	// Number of results we got.
+
+	struct timeval	tv;		// Holds timeout values.
+
+	char const 	*error = NULL;
+	char		*extra = NULL;
+
+	int 		i;
+
+	rad_assert(*pconn && (*pconn)->handle);
+
+	/*
+	 *	OpenLDAP library doesn't declare attrs array as const, but
+	 *	it really should be *sigh*.
+	 */
+	char **search_attrs;
+	memcpy(&search_attrs, &attrs, sizeof(attrs));
+
+	/*
+	 *	Do all searches as the admin user.
+	 */
+	if ((*pconn)->rebound) {
+		status = rlm_ldap_bind(inst, request, pconn, (*pconn)->inst->admin_identity,
+				       (*pconn)->inst->admin_password, &(*pconn)->inst->admin_sasl, true);
+		if (status != LDAP_PROC_SUCCESS) {
+			return LDAP_PROC_ERROR;
+		}
+
+		rad_assert(*pconn);
+
+		(*pconn)->rebound = false;
+	}
+
+	if (filter) {
+		LDAP_DBG_REQ("Performing search in \"%s\" with filter \"%s\", scope \"%s\"", dn, filter,
+			     fr_int2str(ldap_scope, scope, "<INVALID>"));
+	} else {
+		LDAP_DBG_REQ("Performing unfiltered search in \"%s\", scope \"%s\"", dn,
+			     fr_int2str(ldap_scope, scope, "<INVALID>"));
+	}
+	/*
+	 *	If LDAP search produced an error it should also be logged
+	 *	to the ld. result should pick it up without us
+	 *	having to pass it explicitly.
+	 */
+	memset(&tv, 0, sizeof(tv));
+	tv.tv_sec = inst->res_timeout;
+
+	/*
+	 *	For sanity, for when no connections are viable,
+	 *	and we can't make a new one.
+	 */
+	for (i = fr_connection_pool_get_num(inst->pool); i >= 0; i--) {
+		(void) ldap_search_ext((*pconn)->handle, dn, scope, filter, search_attrs,
+				       0, serverctrls, clientctrls, &tv, 0, &msgid);
+
+		LDAP_DBG_REQ("Waiting for search result...");
+		status = rlm_ldap_result(inst, *pconn, msgid, dn, &our_result, &error, &extra);
+		switch (status) {
+		case LDAP_PROC_SUCCESS:
+			break;
+
+		/*
+		 *	Invalid DN isn't a failure when searching.
+		 *	The DN may be xlat expanded so may point directly
+		 *	to an LDAP object. If that can't be located, it's
+		 *	the same as notfound.
+		 */
+		case LDAP_PROC_BAD_DN:
+			LDAP_DBG_REQ("%s", error);
+			if (extra) LDAP_DBG_REQ("%s", extra);
+			break;
+
+		case LDAP_PROC_RETRY:
+			*pconn = fr_connection_reconnect(inst->pool, *pconn);
+			if (*pconn) {
+				LDAP_DBGW_REQ("Search failed: %s. Got new socket, retrying...", error);
+
+				talloc_free(extra); /* don't leak debug info */
+
+				continue;
+			}
+
+			status = LDAP_PROC_ERROR;
+
+			/* FALL-THROUGH */
+		default:
+			LDAP_ERR_REQ("Failed performing search: %s", error);
+			if (extra) LDAP_ERR_REQ("%s", extra);
+
+			goto finish;
+		}
+
+		break;
+	}
+
+	if (i < 0) {
+		LDAP_ERR_REQ("Hit reconnection limit");
+		status = LDAP_PROC_ERROR;
+
+		goto finish;
+	}
+
+	count = ldap_count_entries((*pconn)->handle, our_result);
+	if (count < 0) {
+		LDAP_ERR_REQ("Error counting results: %s", rlm_ldap_error_str(*pconn));
+		status = LDAP_PROC_ERROR;
+
+		ldap_msgfree(our_result);
+		our_result = NULL;
+	} else if (count == 0) {
+		LDAP_DBG_REQ("Search returned no results");
+		status = LDAP_PROC_NO_RESULT;
+
+		ldap_msgfree(our_result);
+		our_result = NULL;
+	}
+
+finish:
+	talloc_free(extra);
+
+	/*
+	 *	We always need to get the result to count entries, but the caller
+	 *	may not of requested one. If that's the case, free it, else write
+	 *	it to where our caller said.
+	 */
+	if (!result) {
+		if (our_result) ldap_msgfree(our_result);
+	} else {
+		*result = our_result;
+	}
+
+	return status;
+}
+
+/** Modify something in the LDAP directory
+ *
+ * Binds as the administrative user and attempts to modify an LDAP object.
+ *
+ * @param[in] inst rlm_ldap configuration.
+ * @param[in] request Current request.
+ * @param[in,out] pconn to use. May change as this function calls functions which auto re-connect.
+ * @param[in] dn of the object to modify.
+ * @param[in] mods to make, see 'man ldap_modify' for more information.
+ * @return One of the LDAP_PROC_* (#ldap_rcode_t) values.
+ */
+ldap_rcode_t rlm_ldap_modify(rlm_ldap_t const *inst, REQUEST *request, ldap_handle_t **pconn,
+			     char const *dn, LDAPMod *mods[])
+{
+	ldap_rcode_t	status = LDAP_PROC_ERROR;
+
+	int		msgid;		// Message id returned by ldap_search_ext.
+
+	char const 	*error = NULL;
+	char		*extra = NULL;
+
+	int 		i;
+
+	rad_assert(*pconn && (*pconn)->handle);
+
+	/*
+	 *	Perform all modifications as the admin user.
+	 */
+	if ((*pconn)->rebound) {
+		status = rlm_ldap_bind(inst, request, pconn, (*pconn)->inst->admin_identity,
+				       (*pconn)->inst->admin_password, &(*pconn)->inst->admin_sasl, true);
+		if (status != LDAP_PROC_SUCCESS) {
+			return LDAP_PROC_ERROR;
+		}
+
+		rad_assert(*pconn);
+
+		(*pconn)->rebound = false;
+	}
+
+	/*
+	 *	For sanity, for when no connections are viable,
+	 *	and we can't make a new one.
+	 */
+	for (i = fr_connection_pool_get_num(inst->pool); i >= 0; i--) {
+		RDEBUG2("Modifying object with DN \"%s\"", dn);
+		(void) ldap_modify_ext((*pconn)->handle, dn, mods, NULL, NULL, &msgid);
+
+		RDEBUG2("Waiting for modify result...");
+		status = rlm_ldap_result(inst, *pconn, msgid, dn, NULL, &error, &extra);
+		switch (status) {
+		case LDAP_PROC_SUCCESS:
+			break;
+
+		case LDAP_PROC_RETRY:
+			*pconn = fr_connection_reconnect(inst->pool, *pconn);
+			if (*pconn) {
+				RWDEBUG("Modify failed: %s. Got new socket, retrying...", error);
+
+				talloc_free(extra); /* don't leak debug info */
+				continue;
+			}
+
+			status = LDAP_PROC_ERROR;
+
+			/* FALL-THROUGH */
+		default:
+			REDEBUG("Failed modifying object: %s", error);
+			REDEBUG("%s", extra);
+
+			goto finish;
+		}
+
+		break;
+	}
+
+	if (i < 0) {
+		LDAP_ERR_REQ("Hit reconnection limit");
+		status = LDAP_PROC_ERROR;
+	}
+
+finish:
+	talloc_free(extra);
+
+	return status;
+}
+
+/** Retrieve the DN of a user object
+ *
+ * Retrieves the DN of a user and adds it to the control list as LDAP-UserDN. Will also retrieve any
+ * attributes passed and return the result in *result.
+ *
+ * This potentially allows for all authorization and authentication checks to be performed in one
+ * ldap search operation, which is a big bonus given the number of crappy, slow *cough*AD*cough*
+ * LDAP directory servers out there.
+ *
+ * @param[in] inst rlm_ldap configuration.
+ * @param[in] request Current request.
+ * @param[in,out] pconn to use. May change as this function calls functions which auto re-connect.
+ * @param[in] attrs Additional attributes to retrieve, may be NULL.
+ * @param[in] force Query even if the User-DN already exists.
+ * @param[out] result Where to write the result, may be NULL in which case result is discarded.
+ * @param[out] rcode The status of the operation, one of the RLM_MODULE_* codes.
+ * @return The user's DN or NULL on error.
+ */
+char const *rlm_ldap_find_user(rlm_ldap_t const *inst, REQUEST *request, ldap_handle_t **pconn,
+			       char const *attrs[], bool force, LDAPMessage **result, rlm_rcode_t *rcode)
+{
+	static char const *tmp_attrs[] = { NULL };
+
+	ldap_rcode_t	status;
+	VALUE_PAIR	*vp = NULL;
+	LDAPMessage	*tmp_msg = NULL, *entry = NULL;
+	int		ldap_errno;
+	int		cnt;
+	char		*dn = NULL;
+	char const	*filter = NULL;
+	char	    	filter_buff[LDAP_MAX_FILTER_STR_LEN];
+	char const	*base_dn;
+	char	    	base_dn_buff[LDAP_MAX_DN_STR_LEN];
+	LDAPControl	*serverctrls[] = { inst->userobj_sort_ctrl, NULL };
+
+	bool freeit = false;					//!< Whether the message should
+								//!< be freed after being processed.
+
+	*rcode = RLM_MODULE_FAIL;
+
+	if (!result) {
+		result = &tmp_msg;
+		freeit = true;
+	}
+	*result = NULL;
+
+	if (!attrs) {
+		memset(&attrs, 0, sizeof(tmp_attrs));
+	}
+
+	/*
+	 *	If the caller isn't looking for the result we can just return the current userdn value.
+	 */
+	if (!force) {
+		vp = fr_pair_find_by_da(request->config, inst->user_dn_da, TAG_ANY);
+		if (vp) {
+			RDEBUG("Using user DN from request \"%s\"", vp->vp_strvalue);
+			*rcode = RLM_MODULE_OK;
+			return vp->vp_strvalue;
+		}
+	}
+
+	/*
+	 *	Perform all searches as the admin user.
+	 */
+	if ((*pconn)->rebound) {
+		status = rlm_ldap_bind(inst, request, pconn, (*pconn)->inst->admin_identity,
+				       (*pconn)->inst->admin_password, &(*pconn)->inst->admin_sasl, true);
+		if (status != LDAP_PROC_SUCCESS) {
+			*rcode = RLM_MODULE_FAIL;
+			return NULL;
+		}
+
+		rad_assert(*pconn);
+
+		(*pconn)->rebound = false;
+	}
+
+	if (inst->userobj_filter) {
+		if (tmpl_expand(&filter, filter_buff, sizeof(filter_buff), request, inst->userobj_filter,
+				rlm_ldap_escape_func, NULL) < 0) {
+			REDEBUG("Unable to create filter");
+			*rcode = RLM_MODULE_INVALID;
+
+			return NULL;
+		}
+	}
+
+	if (tmpl_expand(&base_dn, base_dn_buff, sizeof(base_dn_buff), request,
+			inst->userobj_base_dn, rlm_ldap_escape_func, NULL) < 0) {
+		REDEBUG("Unable to create base_dn");
+		*rcode = RLM_MODULE_INVALID;
+
+		return NULL;
+	}
+
+	status = rlm_ldap_search(result, inst, request, pconn, base_dn,
+				 inst->userobj_scope, filter, attrs, serverctrls, NULL);
+	switch (status) {
+	case LDAP_PROC_SUCCESS:
+		break;
+
+	case LDAP_PROC_BAD_DN:
+	case LDAP_PROC_NO_RESULT:
+		*rcode = RLM_MODULE_NOTFOUND;
+		return NULL;
+
+	default:
+		*rcode = RLM_MODULE_FAIL;
+		return NULL;
+	}
+
+	rad_assert(*pconn);
+
+	/*
+	 *	Forbid the use of unsorted search results that
+	 *	contain multiple entries, as it's a potential
+	 *	security issue, and likely non deterministic.
+	 */
+	if (!inst->userobj_sort_ctrl) {
+		cnt = ldap_count_entries((*pconn)->handle, *result);
+		if (cnt > 1) {
+			REDEBUG("Ambiguous search result, returned %i unsorted entries (should return 1 or 0).  "
+				"Enable sorting, or specify a more restrictive base_dn, filter or scope", cnt);
+			REDEBUG("The following entries were returned:");
+			RINDENT();
+			for (entry = ldap_first_entry((*pconn)->handle, *result);
+			     entry;
+			     entry = ldap_next_entry((*pconn)->handle, entry)) {
+				dn = ldap_get_dn((*pconn)->handle, entry);
+				REDEBUG("%s", dn);
+				ldap_memfree(dn);
+			}
+			REXDENT();
+			*rcode = RLM_MODULE_INVALID;
+			goto finish;
+		}
+	}
+
+	entry = ldap_first_entry((*pconn)->handle, *result);
+	if (!entry) {
+		ldap_get_option((*pconn)->handle, LDAP_OPT_RESULT_CODE, &ldap_errno);
+		REDEBUG("Failed retrieving entry: %s",
+			ldap_err2string(ldap_errno));
+
+		goto finish;
+	}
+
+	dn = ldap_get_dn((*pconn)->handle, entry);
+	if (!dn) {
+		ldap_get_option((*pconn)->handle, LDAP_OPT_RESULT_CODE, &ldap_errno);
+		REDEBUG("Retrieving object DN from entry failed: %s", ldap_err2string(ldap_errno));
+
+		goto finish;
+	}
+	rlm_ldap_normalise_dn(dn, dn);
+
+	/*
+	 *	We can't use fr_pair_make here to copy the value into the
+	 *	attribute, as the dn must be copied into the attribute
+	 *	verbatim (without de-escaping).
+	 *
+	 *	Special chars are pre-escaped by libldap, and because
+	 *	we pass the string back to libldap we must not alter it.
+	 */
+	RDEBUG("User object found at DN \"%s\"", dn);
+	vp = fr_pair_afrom_da(request, inst->user_dn_da);
+	if (vp) {
+		fr_pair_add(&request->config, vp);
+		fr_pair_value_strcpy(vp, dn);
+		*rcode = RLM_MODULE_OK;
+	}
+	ldap_memfree(dn);
+
+finish:
+	if ((freeit || (*rcode != RLM_MODULE_OK)) && *result) {
+		ldap_msgfree(*result);
+		*result = NULL;
+	}
+
+	return vp ? vp->vp_strvalue : NULL;
+}
+
+/** Check for presence of access attribute in result
+ *
+ * @param[in] inst rlm_ldap configuration.
+ * @param[in] request Current request.
+ * @param[in] conn used to retrieve access attributes.
+ * @param[in] entry retrieved by rlm_ldap_find_user or rlm_ldap_search.
+ * @return
+ *	- #RLM_MODULE_USERLOCK if the user was denied access.
+ *	- #RLM_MODULE_OK otherwise.
+ */
+rlm_rcode_t rlm_ldap_check_access(rlm_ldap_t const *inst, REQUEST *request,
+				  ldap_handle_t const *conn, LDAPMessage *entry)
+{
+	rlm_rcode_t rcode = RLM_MODULE_OK;
+	struct berval **values = NULL;
+
+	values = ldap_get_values_len(conn->handle, entry, inst->userobj_access_attr);
+	if (values) {
+		if (inst->access_positive) {
+			if ((values[0]->bv_len >= 5) && (strncasecmp(values[0]->bv_val, "false", 5) == 0)) {
+				RDEBUG("\"%s\" attribute exists but is set to 'false' - user locked out",
+				       inst->userobj_access_attr);
+				rcode = RLM_MODULE_USERLOCK;
+			}
+			/* RLM_MODULE_OK set above... */
+		} else if ((values[0]->bv_len < 5) || (strncasecmp(values[0]->bv_val, "false", 5) != 0)) {
+			RDEBUG("\"%s\" attribute exists - user locked out", inst->userobj_access_attr);
+			rcode = RLM_MODULE_USERLOCK;
+		}
+		ldap_value_free_len(values);
+	} else if (inst->access_positive) {
+		RDEBUG("No \"%s\" attribute - user locked out", inst->userobj_access_attr);
+		rcode = RLM_MODULE_USERLOCK;
+	}
+
+	return rcode;
+}
+
+/** Verify we got a password from the search
+ *
+ * Checks to see if after the LDAP to RADIUS mapping has been completed that a reference password.
+ *
+ * @param inst rlm_ldap configuration.
+ * @param request Current request.
+ */
+void rlm_ldap_check_reply(rlm_ldap_t const *inst, REQUEST *request)
+{
+       /*
+	*	More warning messages for people who can't be bothered to read the documentation.
+	*
+	*	Expect_password is set when we process the mapping, and is only true if there was a mapping between
+	*	an LDAP attribute and a password reference attribute in the control list.
+	*/
+	if (inst->expect_password && (rad_debug_lvl > 1)) {
+		if (!fr_pair_find_by_num(request->config, PW_CLEARTEXT_PASSWORD, 0, TAG_ANY) &&
+		    !fr_pair_find_by_num(request->config, PW_NT_PASSWORD, 0, TAG_ANY) &&
+		    !fr_pair_find_by_num(request->config, PW_USER_PASSWORD, 0, TAG_ANY) &&
+		    !fr_pair_find_by_num(request->config, PW_PASSWORD_WITH_HEADER, 0, TAG_ANY) &&
+		    !fr_pair_find_by_num(request->config, PW_CRYPT_PASSWORD, 0, TAG_ANY)) {
+			RWDEBUG("No \"known good\" password added. Ensure the admin user has permission to "
+				"read the password attribute");
+			RWDEBUG("PAP authentication will *NOT* work with Active Directory (if that is what you "
+				"were trying to configure)");
+		}
+       }
+}
+
+#if LDAP_SET_REBIND_PROC_ARGS == 3
+/** Callback for OpenLDAP to rebind and chase referrals
+ *
+ * Called by OpenLDAP when it receives a referral and has to rebind.
+ *
+ * @param handle to rebind.
+ * @param url to bind to.
+ * @param request that triggered the rebind.
+ * @param msgid that triggered the rebind.
+ * @param ctx rlm_ldap configuration.
+ */
+static int rlm_ldap_rebind(LDAP *handle, LDAP_CONST char *url, UNUSED ber_tag_t request, UNUSED ber_int_t msgid,
+			   void *ctx)
+{
+	ldap_rcode_t status;
+	ldap_handle_t *conn = talloc_get_type_abort(ctx, ldap_handle_t);
+
+	int ldap_errno;
+
+	rad_assert(handle == conn->handle);
+
+	DEBUG("rlm_ldap (%s): Rebinding to URL %s", conn->inst->name, url);
+
+	status = rlm_ldap_bind(conn->inst, NULL, &conn, conn->inst->admin_identity, conn->inst->admin_password,
+			       &(conn->inst->admin_sasl), false);
+	if (status != LDAP_PROC_SUCCESS) {
+		ldap_get_option(handle, LDAP_OPT_ERROR_NUMBER, &ldap_errno);
+
+		return ldap_errno;
+	}
+
+
+	return LDAP_SUCCESS;
+}
+#endif
+
+int rlm_ldap_global_init(rlm_ldap_t *inst)
+{
+	int ldap_errno;
+
+#define do_ldap_global_option(_option, _name, _value) \
+	if (ldap_set_option(NULL, _option, _value) != LDAP_OPT_SUCCESS) { \
+		ldap_get_option(NULL, LDAP_OPT_ERROR_NUMBER, &ldap_errno); \
+		ERROR("Failed setting global option %s: %s", _name, \
+			 (ldap_errno != LDAP_SUCCESS) ? ldap_err2string(ldap_errno) : "Unknown error"); \
+		return -1;\
+	}
+
+#define maybe_ldap_global_option(_option, _name, _value) \
+	if (_value) do_ldap_global_option(_option, _name, _value)
+
+#ifdef LDAP_OPT_DEBUG_LEVEL
+	/*
+	 *	Can't use do_ldap_global_option
+	 */
+	if (inst->ldap_debug) do_ldap_global_option(LDAP_OPT_DEBUG_LEVEL, "ldap_debug", &(inst->ldap_debug));
+#endif
+
+#ifdef LDAP_OPT_X_TLS_RANDOM_FILE
+	/*
+	 *	OpenLDAP will error out if we attempt to set
+	 *	this on a handle. Presumably it's global in
+	 *	OpenSSL too.
+	 */
+	maybe_ldap_global_option(LDAP_OPT_X_TLS_RANDOM_FILE, "random_file", inst->tls_random_file);
+#endif
+	return 0;
+}
+
+/** Close and delete a connection
+ *
+ * Unbinds the LDAP connection, informing the server and freeing any memory, then releases the memory used by the
+ * connection handle.
+ *
+ * @param conn to destroy.
+ * @return always indicates success.
+ */
+static int _mod_conn_free(ldap_handle_t *conn)
+{
+	if (conn->handle) {
+		DEBUG3("rlm_ldap: Closing libldap handle %p", conn->handle);
+#ifdef HAVE_LDAP_UNBIND_EXT_S
+		ldap_unbind_ext_s(conn->handle, NULL, NULL);
+#else
+		ldap_unbind_s(conn->handle);
+#endif
+	}
+
+	return 0;
+}
+
+/** Create and return a new connection
+ *
+ * Create a new ldap connection and allocate memory for a new rlm_handle_t
+ */
+void *mod_conn_create(TALLOC_CTX *ctx, void *instance)
+{
+	ldap_rcode_t status;
+
+	int ldap_errno, ldap_version;
+	struct timeval tv;
+
+	rlm_ldap_t *inst = instance;
+	ldap_handle_t *conn;
+
+	/*
+	 *	Allocate memory for the handle.
+	 */
+	conn = talloc_zero(ctx, ldap_handle_t);
+	if (!conn) return NULL;
+	talloc_set_destructor(conn, _mod_conn_free);
+
+	conn->inst = inst;
+	conn->rebound = false;
+
+	DEBUG("rlm_ldap (%s): Connecting to %s", inst->name, inst->server);
+#ifdef HAVE_LDAP_INITIALIZE
+	ldap_errno = ldap_initialize(&conn->handle, inst->server);
+	if (ldap_errno != LDAP_SUCCESS) {
+		LDAP_ERR("ldap_initialize failed: %s", ldap_err2string(ldap_errno));
+		goto error;
+	}
+#else
+	conn->handle = ldap_init(inst->server, inst->port);
+	if (!conn->handle) {
+		LDAP_ERR("ldap_init failed");
+		goto error;
+	}
+#endif
+	DEBUG3("rlm_ldap (%s): New libldap handle %p", inst->name, conn->handle);
+
+	/*
+	 *	We now have a connection structure, but no actual connection.
+	 *
+	 *	Set a bunch of LDAP options, using common code.
+	 */
+#define do_ldap_option(_option, _name, _value) \
+	if (ldap_set_option(conn->handle, _option, _value) != LDAP_OPT_SUCCESS) { \
+		ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &ldap_errno); \
+		LDAP_ERR("Failed setting connection option %s: %s", _name, \
+			 (ldap_errno != LDAP_SUCCESS) ? ldap_err2string(ldap_errno) : "Unknown error"); \
+		goto error;\
+	}
+
+#define maybe_ldap_option(_option, _name, _value) \
+	if (_value) do_ldap_option(_option, _name, _value)
+
+	/*
+	 *	Leave "dereference" unset to use the OpenLDAP default.
+	 */
+	if (inst->dereference_str) {
+		do_ldap_option(LDAP_OPT_DEREF, "dereference", &(inst->dereference));
+	}
+
+	/*
+	 *	Leave "chase_referrals" unset to use the OpenLDAP default.
+	 */
+	if (!inst->chase_referrals_unset) {
+		if (inst->chase_referrals) {
+			do_ldap_option(LDAP_OPT_REFERRALS, "chase_referrals", LDAP_OPT_ON);
+
+			if (inst->rebind == true) {
+#if LDAP_SET_REBIND_PROC_ARGS == 3
+				ldap_set_rebind_proc(conn->handle, rlm_ldap_rebind, conn);
+#endif
+			}
+		} else {
+			do_ldap_option(LDAP_OPT_REFERRALS, "chase_referrals", LDAP_OPT_OFF);
+		}
+	}
+
+#ifdef LDAP_OPT_NETWORK_TIMEOUT
+	if (inst->net_timeout) {
+		memset(&tv, 0, sizeof(tv));
+		tv.tv_sec = inst->net_timeout;
+
+		do_ldap_option(LDAP_OPT_NETWORK_TIMEOUT, "net_timeout", &tv);
+	}
+#endif
+
+	do_ldap_option(LDAP_OPT_TIMELIMIT, "srv_timelimit", &(inst->srv_timelimit));
+
+	ldap_version = LDAP_VERSION3;
+	do_ldap_option(LDAP_OPT_PROTOCOL_VERSION, "ldap_version", &ldap_version);
+
+#ifdef LDAP_OPT_X_KEEPALIVE_IDLE
+	do_ldap_option(LDAP_OPT_X_KEEPALIVE_IDLE, "keepalive idle", &(inst->keepalive_idle));
+#endif
+
+#ifdef LDAP_OPT_X_KEEPALIVE_PROBES
+	do_ldap_option(LDAP_OPT_X_KEEPALIVE_PROBES, "keepalive probes", &(inst->keepalive_probes));
+#endif
+
+#ifdef LDAP_OPT_X_KEEPALIVE_INTERVAL
+	do_ldap_option(LDAP_OPT_X_KEEPALIVE_INTERVAL, "keepalive interval", &(inst->keepalive_interval));
+#endif
+
+#ifdef HAVE_LDAP_START_TLS_S
+	/*
+	 *	Set all of the TLS options
+	 */
+	if (inst->tls_mode) {
+		do_ldap_option(LDAP_OPT_X_TLS, "tls_mode", &(inst->tls_mode));
+	}
+
+	maybe_ldap_option(LDAP_OPT_X_TLS_CACERTFILE, "ca_file", inst->tls_ca_file);
+	maybe_ldap_option(LDAP_OPT_X_TLS_CACERTDIR, "ca_path", inst->tls_ca_path);
+
+
+	/*
+	 *	Set certificate options
+	 */
+	maybe_ldap_option(LDAP_OPT_X_TLS_CERTFILE, "certificate_file", inst->tls_certificate_file);
+	maybe_ldap_option(LDAP_OPT_X_TLS_KEYFILE, "private_key_file", inst->tls_private_key_file);
+
+#  ifdef LDAP_OPT_X_TLS_REQUIRE_CERT
+	if (inst->tls_require_cert_str) {
+		do_ldap_option(LDAP_OPT_X_TLS_REQUIRE_CERT, "require_cert", &inst->tls_require_cert);
+	}
+#  endif
+
+#  ifdef LDAP_OPT_X_TLS_PROTOCOL_MIN
+	if (inst->tls_min_version_str) {
+		do_ldap_option(LDAP_OPT_X_TLS_PROTOCOL_MIN, "tls_min_version", &inst->tls_min_version);
+	}
+#  endif
+
+	/*
+	 *	Counter intuitively the TLS context appears to need to be initialised
+	 *	after all the TLS options are set on the handle.
+	 */
+#  ifdef LDAP_OPT_X_TLS_NEWCTX
+	{
+		/* Always use the new TLS configuration context */
+		int is_server = 0;
+		do_ldap_option(LDAP_OPT_X_TLS_NEWCTX, "new TLS context", &is_server);
+
+	}
+#  endif
+
+	/*
+	 *	And finally start the TLS code.
+	 */
+	if (inst->start_tls) {
+		if (inst->port == 636) {
+			WARN("Told to Start TLS on LDAPS port this will probably fail, please correct the "
+			     "configuration");
+		}
+
+		if (ldap_start_tls_s(conn->handle, NULL, NULL) != LDAP_SUCCESS) {
+			ldap_get_option(conn->handle, LDAP_OPT_ERROR_NUMBER, &ldap_errno);
+
+			LDAP_ERR("Could not start TLS: %s", ldap_err2string(ldap_errno));
+			goto error;
+		}
+	}
+#endif /* HAVE_LDAP_START_TLS_S */
+
+	if (inst->sasl_secprops) {
+		do_ldap_option(LDAP_OPT_X_SASL_SECPROPS, "SASL_SECPROPS", inst->sasl_secprops);
+	}
+
+	status = rlm_ldap_bind(inst, NULL, &conn, conn->inst->admin_identity, conn->inst->admin_password,
+			       &(conn->inst->admin_sasl), false);
+	if (status != LDAP_PROC_SUCCESS) {
+		goto error;
+	}
+
+	return conn;
+
+error:
+	talloc_free(conn);
+
+	return NULL;
+}
+
+/** Gets an LDAP socket from the connection pool
+ *
+ * Retrieve a socket from the connection pool, or NULL on error (of if no sockets are available).
+ *
+ * @param inst rlm_ldap configuration.
+ * @param request Current request (may be NULL).
+ */
+ldap_handle_t *mod_conn_get(rlm_ldap_t const *inst, UNUSED REQUEST *request)
+{
+	return fr_connection_get(inst->pool);
+}
+
+/** Frees an LDAP socket back to the connection pool
+ *
+ * If the socket was rebound chasing a referral onto another server then we destroy it.
+ * If the socket was rebound to another user on the same server, we let the next caller rebind it.
+ *
+ * @param inst rlm_ldap configuration.
+ * @param conn to release.
+ */
+void mod_conn_release(rlm_ldap_t const *inst, ldap_handle_t *conn)
+{
+	/*
+	 *	Could have already been free'd due to a previous error.
+	 */
+	if (!conn) return;
+
+	fr_connection_release(inst->pool, conn);
+	return;
+}