Added ldapdb_starttls keyword

contrib/ldapsasl/README

@@ -64,3 +64,12 @@ sasl-regexp uidNumber=(.*)\\+gidNumber=(.*),cn=peercred,cn=external,cn=auth
 sasl-regexp uid=(.*),cn=external,cn=auth
 	ldap:///dc=example,dc=com??sub?(uid=$1)
 
+One more update: you can use the ldapdb_starttls keyword to use the
+StartTLS extended operation on an LDAP session. This item may be set
+to either "try" or "demand", e.g.:
+
+ldapdb_uri: ldap://ldap.example.com
+ldapdb_starttls: try
+
+When set to "try" any failure in StartTLS is ignored. When set to "demand"
+then any failure aborts the connection.

contrib/ldapsasl/ldapdb.c

@@ -38,6 +38,7 @@ typedef struct ldapctx {
 	struct berval id;	/* SASL authcid to bind as */
 	struct berval pw;	/* password for bind */
 	struct berval mech;	/* SASL mech */
+	int use_tls;		/* Issue StartTLS request? */
 } ldapctx;
 
 typedef struct gluectx {
@@ -145,6 +146,11 @@ static void ldapdb_auxprop_lookup(void *glob_context,
     i = LDAP_VERSION3;
     ret = ldap_set_option(ld, LDAP_OPT_PROTOCOL_VERSION, &i);
 
+    /* If TLS is set and it fails, continue or bail out as requested */
+    if (ctx->use_tls && ldap_start_tls_s(ld, NULL, NULL) != LDAP_SUCCESS) {
+    	if (ctx->use_tls > 1) goto done;
+    }
+
     ret = ldap_sasl_interactive_bind_s(ld, NULL, ctx->mech.bv_val, NULL, NULL,
     	LDAP_SASL_QUIET, ldapdb_interact, &gc);
     if (ret != LDAP_SUCCESS) goto done;
@@ -210,6 +216,8 @@ static int ldapdb_auxprop_plug_init(const sasl_utils_t *utils,
 
     if(max_version < SASL_AUXPROP_PLUG_VERSION) return SASL_BADVERS;
     
+    memset(&tmp, 0, sizeof(tmp));
+
     utils->getopt(utils->getopt_context, ldapdb, "ldapdb_uri", &tmp.uri, NULL);
     if(!tmp.uri) return SASL_BADPARAM;
 
@@ -222,6 +230,12 @@ static int ldapdb_auxprop_plug_init(const sasl_utils_t *utils,
     utils->getopt(utils->getopt_context, ldapdb, "ldapdb_mech",
     	(const char **)&tmp.mech.bv_val, &len);
     tmp.mech.bv_len = len;
+    utils->getopt(utils->getopt_context, ldapdb, "ldapdb_starttls", &s, NULL);
+    if (s)
+    {
+    	if (!strcasecmp(s, "demand")) tmp.use_tls = 2;
+	else if (!strcasecmp(s, "try")) tmp.use_tls = 1;
+    }
     utils->getopt(utils->getopt_context, ldapdb, "ldapdb_rc", &s, &len);
     if (s)
     {