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-rw-r--r--servers/slapd/module.c367
1 files changed, 367 insertions, 0 deletions
diff --git a/servers/slapd/module.c b/servers/slapd/module.c
new file mode 100644
index 0000000..048ce8d
--- /dev/null
+++ b/servers/slapd/module.c
@@ -0,0 +1,367 @@
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 1998-2022 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>.
+ */
+
+#include "portable.h"
+#include <stdio.h>
+#include "slap.h"
+
+#ifdef SLAPD_MODULES
+
+#include <ltdl.h>
+
+typedef int (*MODULE_INIT_FN)(
+ int argc,
+ char *argv[]);
+typedef int (*MODULE_LOAD_FN)(
+ const void *module,
+ const char *filename);
+typedef int (*MODULE_TERM_FN)(void);
+
+
+struct module_regtable_t {
+ char *type;
+ MODULE_LOAD_FN proc;
+} module_regtable[] = {
+ { "null", load_null_module },
+#ifdef SLAPD_EXTERNAL_EXTENSIONS
+ { "extension", load_extop_module },
+#endif
+ { NULL, NULL }
+};
+
+typedef struct module_loaded_t {
+ struct module_loaded_t *next;
+ lt_dlhandle lib;
+ char name[1];
+} module_loaded_t;
+
+module_loaded_t *module_list = NULL;
+
+static int module_int_unload (module_loaded_t *module);
+
+#ifdef HAVE_EBCDIC
+static char ebuf[BUFSIZ];
+#endif
+
+int module_init (void)
+{
+ if (lt_dlinit()) {
+ const char *error = lt_dlerror();
+#ifdef HAVE_EBCDIC
+ strcpy( ebuf, error );
+ __etoa( ebuf );
+ error = ebuf;
+#endif
+ Debug(LDAP_DEBUG_ANY, "lt_dlinit failed: %s\n", error );
+
+ return -1;
+ }
+
+ return module_path( LDAP_MODULEDIR );
+}
+
+int module_kill (void)
+{
+ /* unload all modules before shutdown */
+ while (module_list != NULL) {
+ module_int_unload(module_list);
+ }
+
+ if (lt_dlexit()) {
+ const char *error = lt_dlerror();
+#ifdef HAVE_EBCDIC
+ strcpy( ebuf, error );
+ __etoa( ebuf );
+ error = ebuf;
+#endif
+ Debug(LDAP_DEBUG_ANY, "lt_dlexit failed: %s\n", error );
+
+ return -1;
+ }
+ return 0;
+}
+
+void * module_handle( const char *file_name )
+{
+ module_loaded_t *module;
+
+ for ( module = module_list; module; module= module->next ) {
+ if ( !strcmp( module->name, file_name )) {
+ return module;
+ }
+ }
+ return NULL;
+}
+
+int module_unload( const char *file_name )
+{
+ module_loaded_t *module;
+
+ module = module_handle( file_name );
+ if ( module ) {
+ module_int_unload( module );
+ return 0;
+ }
+ return -1; /* not found */
+}
+
+int module_load(const char* file_name, int argc, char *argv[])
+{
+ module_loaded_t *module;
+ const char *error;
+ int rc;
+ MODULE_INIT_FN initialize;
+#ifdef HAVE_EBCDIC
+#define file ebuf
+#else
+#define file file_name
+#endif
+
+ module = module_handle( file_name );
+ if ( module ) {
+ Debug( LDAP_DEBUG_ANY, "module_load: (%s) already loaded\n",
+ file_name );
+ return -1;
+ }
+
+ /* If loading a backend, see if we already have it */
+ if ( !strncasecmp( file_name, "back_", 5 )) {
+ char *name = (char *)file_name + 5;
+ char *dot = strchr( name, '.');
+ if (dot) *dot = '\0';
+ rc = backend_info( name ) != NULL;
+ if (dot) *dot = '.';
+ if ( rc ) {
+ Debug( LDAP_DEBUG_CONFIG, "module_load: (%s) already present (static)\n",
+ file_name );
+ return 0;
+ }
+ } else {
+ /* check for overlays too */
+ char *dot = strchr( file_name, '.' );
+ if ( dot ) *dot = '\0';
+ rc = overlay_find( file_name ) != NULL;
+ if ( dot ) *dot = '.';
+ if ( rc ) {
+ Debug( LDAP_DEBUG_CONFIG, "module_load: (%s) already present (static)\n",
+ file_name );
+ return 0;
+ }
+ }
+
+ module = (module_loaded_t *)ch_calloc(1, sizeof(module_loaded_t) +
+ strlen(file_name));
+ if (module == NULL) {
+ Debug(LDAP_DEBUG_ANY, "module_load failed: (%s) out of memory\n", file_name );
+
+ return -1;
+ }
+ strcpy( module->name, file_name );
+
+#ifdef HAVE_EBCDIC
+ strcpy( file, file_name );
+ __atoe( file );
+#endif
+ /*
+ * The result of lt_dlerror(), when called, must be cached prior
+ * to calling Debug. This is because Debug is a macro that expands
+ * into multiple function calls.
+ */
+ if ((module->lib = lt_dlopenext(file)) == NULL) {
+ error = lt_dlerror();
+#ifdef HAVE_EBCDIC
+ strcpy( ebuf, error );
+ __etoa( ebuf );
+ error = ebuf;
+#endif
+ Debug(LDAP_DEBUG_ANY, "lt_dlopenext failed: (%s) %s\n", file_name,
+ error );
+
+ ch_free(module);
+ return -1;
+ }
+
+ Debug(LDAP_DEBUG_CONFIG, "loaded module %s\n", file_name );
+
+
+#ifdef HAVE_EBCDIC
+#pragma convlit(suspend)
+#endif
+ if ((initialize = lt_dlsym(module->lib, "init_module")) == NULL) {
+#ifdef HAVE_EBCDIC
+#pragma convlit(resume)
+#endif
+ Debug(LDAP_DEBUG_CONFIG, "module %s: no init_module() function found\n",
+ file_name );
+
+ lt_dlclose(module->lib);
+ ch_free(module);
+ return -1;
+ }
+
+ /* The imported init_module() routine passes back the type of
+ * module (i.e., which part of slapd it should be hooked into)
+ * or -1 for error. If it passes back 0, then you get the
+ * old behavior (i.e., the library is loaded and not hooked
+ * into anything).
+ *
+ * It might be better if the conf file could specify the type
+ * of module. That way, a single module could support multiple
+ * type of hooks. This could be done by using something like:
+ *
+ * moduleload extension /usr/local/openldap/whatever.so
+ *
+ * then we'd search through module_regtable for a matching
+ * module type, and hook in there.
+ */
+ rc = initialize(argc, argv);
+ if (rc == -1) {
+ Debug(LDAP_DEBUG_CONFIG, "module %s: init_module() failed\n",
+ file_name );
+
+ lt_dlclose(module->lib);
+ ch_free(module);
+ return rc;
+ }
+
+ if (rc >= (int)(sizeof(module_regtable) / sizeof(struct module_regtable_t))
+ || module_regtable[rc].proc == NULL)
+ {
+ Debug(LDAP_DEBUG_CONFIG, "module %s: unknown registration type (%d)\n",
+ file_name, rc );
+
+ module_int_unload(module);
+ return -1;
+ }
+
+ rc = (module_regtable[rc].proc)(module, file_name);
+ if (rc != 0) {
+ Debug(LDAP_DEBUG_CONFIG, "module %s: %s module could not be registered\n",
+ file_name, module_regtable[rc].type );
+
+ module_int_unload(module);
+ return rc;
+ }
+
+ module->next = module_list;
+ module_list = module;
+
+ Debug(LDAP_DEBUG_CONFIG, "module %s: %s module registered\n",
+ file_name, module_regtable[rc].type );
+
+ return 0;
+}
+
+int module_path(const char *path)
+{
+#ifdef HAVE_EBCDIC
+ strcpy(ebuf, path);
+ __atoe(ebuf);
+ path = ebuf;
+#endif
+ return lt_dlsetsearchpath( path );
+}
+
+void *module_resolve (const void *module, const char *name)
+{
+#ifdef HAVE_EBCDIC
+ strcpy(ebuf, name);
+ __atoe(ebuf);
+ name = ebuf;
+#endif
+ if (module == NULL || name == NULL)
+ return(NULL);
+ return(lt_dlsym(((module_loaded_t *)module)->lib, name));
+}
+
+static int module_int_unload (module_loaded_t *module)
+{
+ module_loaded_t *mod;
+ MODULE_TERM_FN terminate;
+
+ if (module != NULL) {
+ /* remove module from tracking list */
+ if (module_list == module) {
+ module_list = module->next;
+ } else {
+ for (mod = module_list; mod; mod = mod->next) {
+ if (mod->next == module) {
+ mod->next = module->next;
+ break;
+ }
+ }
+ }
+
+ /* call module's terminate routine, if present */
+#ifdef HAVE_EBCDIC
+#pragma convlit(suspend)
+#endif
+ if ((terminate = lt_dlsym(module->lib, "term_module"))) {
+#ifdef HAVE_EBCDIC
+#pragma convlit(resume)
+#endif
+ terminate();
+ }
+
+ /* close the library and free the memory */
+ lt_dlclose(module->lib);
+ ch_free(module);
+ }
+ return 0;
+}
+
+int load_null_module (const void *module, const char *file_name)
+{
+ return 0;
+}
+
+#ifdef SLAPD_EXTERNAL_EXTENSIONS
+int
+load_extop_module (
+ const void *module,
+ const char *file_name
+)
+{
+ SLAP_EXTOP_MAIN_FN *ext_main;
+ SLAP_EXTOP_GETOID_FN *ext_getoid;
+ struct berval oid;
+ int rc;
+
+ ext_main = (SLAP_EXTOP_MAIN_FN *)module_resolve(module, "ext_main");
+ if (ext_main == NULL) {
+ return(-1);
+ }
+
+ ext_getoid = module_resolve(module, "ext_getoid");
+ if (ext_getoid == NULL) {
+ return(-1);
+ }
+
+ rc = (ext_getoid)(0, &oid, 256);
+ if (rc != 0) {
+ return(rc);
+ }
+ if (oid.bv_val == NULL || oid.bv_len == 0) {
+ return(-1);
+ }
+
+ /* FIXME: this is broken, and no longer needed,
+ * as a module can call load_extop() itself... */
+ rc = load_extop( &oid, ext_main );
+ return rc;
+}
+#endif /* SLAPD_EXTERNAL_EXTENSIONS */
+#endif /* SLAPD_MODULES */
+