LDAP support added

- This patch enables LCDd to retrieve its configuration
  options from an LDAP directory.
- The code was tested with OpenLDAP 2.1.x (21<=x<=22) only.
- LDAP support is disabled by default and has to be enabled
  with ./configure --enable-ldap.
  (See ./configure --help for other options. Not all options
  have any effect yet.)
- Currently only anonymous LDAP binds are supported.
- The DN of the main configuration object has to be passed to LCDd
  instead of the configuration file location:
  LCDd -c "ldap://yourhost.yourcompany.com/cn=config1,cn=lcdproc,dc=yourcompany dc=COM"
  The basic idea behind the LCDproc object classes is that they
  are more or less verbatim copies of the corresponding sections in a
  generic LCDd.conf
- Unfortunately schema files cannot be provided yet, because LCDproc does
  not have a registered OID namespace and OID hijacking is prohibited.

clients/lcdexec/Makefile.am

@@ -1,4 +1,4 @@
 bin_PROGRAMS = lcdexec
 lcdexec_SOURCES = lcdexec.c menu.c menu.h
-lcdexec_LDADD = ../../shared/libLCDstuff.a
+lcdexec_LDADD = @ldap_libs@ ../../shared/libLCDstuff.a
 INCLUDES = -I$(top_srcdir)

clients/lcdproc/Makefile.am

@@ -1,4 +1,4 @@
 bin_PROGRAMS = lcdproc
 lcdproc_SOURCES = main.c main.h mode.c mode.h batt.c batt.h chrono.c chrono.h cpu.c cpu.h cpu_smp.c cpu_smp.h disk.c disk.h load.c load.h mem.c mem.h machine_Linux.c machine_OpenBSD.c machine_FreeBSD.c machine_NetBSD.c machine_SunOS.c
-lcdproc_LDADD = ../../shared/libLCDstuff.a
+lcdproc_LDADD = @ldap_libs@ ../../shared/libLCDstuff.a
 INCLUDES = -I$(top_srcdir)

configure.in

@@ -202,6 +202,186 @@ AC_MODULES_INFO
 
 LCD_DRIVERS_SELECT
 
+dnl ######################################################################
+dnl Open LDAP
+dnl based on code from perdition http://www.vergenet.net/linux/perdition/
+dnl
+dnl not all options have effect at the moment
+
+AC_SUBST(ldap_libs)
+AC_SUBST(ldap_includes)
+AC_SUBST(ldap_schemadir)
+
+AC_MSG_CHECKING([if LDAP support has been enabled]);
+AC_ARG_ENABLE(
+  ldap,
+  [  --enable-ldap           compile with LDAP support.  ],
+  [ 
+    if test "$enable_ldap" = "yes"; then
+      AC_MSG_RESULT("yes")
+    else
+      AC_MSG_RESULT("no")
+    fi
+  ],
+  [ 
+    enable_ldap="no";
+    AC_MSG_RESULT("no") 
+  ]
+)
+
+if test "$enable_ldap" = "yes"; then
+AC_ARG_WITH(
+  ldap-includes,
+  [  --with-ldap-includes=DIR  
+                          Open LDAP include files are in DIR.  ],
+  [ 
+    if test "$withval" = "no"; then 
+     ldap_build_dir=""; 
+    else
+      ldap_includepath="$withval" 
+    fi
+  ],
+  [ 
+    AC_MSG_CHECKING(OpenLDAP include path)
+    for ldap_includepath in /usr/openldap/include /usr/local/openldap/include \
+        /usr/include/openldap /usr/local/include/openldap \
+    	/usr/include /usr/local/include; do
+      if test -f "${ldap_includepath}/ldap.h"; then
+        break
+      fi
+    done
+    AC_MSG_RESULT($ldap_includepath)
+  ]
+)
+fi
+
+ldap_includes="-I$ldap_includepath"
+
+if test "$enable_ldap" = "yes"; then
+AC_ARG_WITH(
+  ldap-libraries,
+  [  --with-ldap-libraries=DIR 
+                          Open LDAP library files are in DIR.  ],
+  [ 
+    if test "$withval" = "no"; then 
+     ldap_build_dir=""; 
+    else
+      ldap_libpath="$withval" 
+    fi
+  ],
+  [ 
+    AC_MSG_CHECKING(OpenLDAP library path)
+    for ldap_libpath in /usr/openldap/lib /usr/local/openldap/lib \
+        /usr/lib/openldap /usr/local/lib/openldap \
+    	/usr/lib /usr/local/lib; do
+      if test -f "${ldap_libpath}/libldap.a" \
+      	-o -f "${ldap_libpath}/libldap.so"; then
+        break
+      fi
+    done
+    AC_MSG_RESULT($ldap_libpath)
+  ]
+)
+fi
+
+ldap_libs="-L$ldap_libpath -lldap -llber"
+
+if test "$enable_ldap" = "yes"; then
+AC_CHECK_FILE(
+  $ldap_includepath/ldap.h,
+  [ : ] ,
+  [ enable_ldap="no" ]
+)
+fi
+
+if test "$enable_ldap" = "yes"; then
+AC_CHECK_LIB(
+  ldap,
+  ldap_url_parse,
+  [ : ],
+  [ enable_ldap="no" ],
+  $ldap_libs
+)
+fi
+
+if test "$enable_ldap" = "yes"; then
+        AC_MSG_CHECKING(OpenLDAP lud_exts in LDAPURLDesc)
+	AC_TRY_COMPILE([#include <stdlib.h>
+			#include <lber.h>
+			#include <ldap.h>],
+		[LDAPURLDesc ludp; 
+		 ludp.lud_exts[0] = NULL;],
+		AC_MSG_RESULT("yes") 
+		AC_DEFINE(WITH_LDAP_LUD_EXTS, 1, Compile with LDAP lud_exts),
+		AC_MSG_RESULT("no")
+AC_MSG_WARN(
+""
+"************************************************************"
+"* Password and Username support will not be built in the"
+"* LDAP module. For Password and Username support compile"
+"* openldap2. Available from openldap.org"
+"************************************************************"
+)
+	)
+fi
+
+if test "$enable_ldap" = "yes"; then
+        AC_CHECK_LIB(ldap, ldap_set_option, 
+	AC_DEFINE(WITH_LDAP_SET_OPTION, 1, Compile with LDAP set_option),
+AC_MSG_WARN(
+""
+"************************************************************"
+"* Cannot expicitly set network timeout or ldap protocol"
+"* version. For ldap_set_option support please use openlap2."
+"* Available from openldap.org"
+"************************************************************"
+),)
+fi
+
+if test "$enable_ldap" = "yes"; then
+AC_ARG_WITH(
+  ldap-schema-directory,
+  [  --with-ldap-schema-directory=DIR 
+                          Open LDAP schema files are in DIR.  ],
+  [ 
+    if test "$withval" = "no"; then 
+     ldap_schemadir=""; 
+    else
+      ldap_schemadir="$withval" 
+    fi
+  ],
+  [ 
+    AC_MSG_CHECKING(OpenLDAP schema path)
+    for ldap_schemadir in /etc/openldap/schema /etc/ldap/schema \
+        /usr/local/openldap/etc/schema; do
+      if test -f "${ldap_schemadir}/openldap.schema"; then
+        break
+      fi
+      ldap_schemadir="Not found"
+    done
+    AC_MSG_RESULT($ldap_schemadir)
+    if test "$ldap_schemadir" = "Not found"; then
+AC_MSG_WARN(
+""
+"************************************************************"
+"* Could not find OpenLDAP schema directory."
+"* lcdproc.schema will not be installed"
+"************************************************************"
+)
+      ldap_schemadir=""
+    fi
+  ]
+)
+fi
+
+if test "$enable_ldap" = "yes"; then
+    AC_DEFINE(WITH_LDAP_SUPPORT, 1, Compile in LDAP support)
+else
+    ldab_libs="";
+    ldap_includes="";
+fi
+
+
 AC_OUTPUT(Makefile
 	shared/Makefile
 	server/Makefile

server/Makefile.am

@@ -1,6 +1,6 @@
 SUBDIRS=drivers commands
 sbin_PROGRAMS=LCDd
 LCDd_SOURCES= client.c client.h clients.c clients.h input.c input.h main.c main.h menuitem.c menuitem.h menu.c menu.h menuscreens.c menuscreens.h parse.c parse.h render.c render.h screen.c screen.h screenlist.c screenlist.h serverscreens.c serverscreens.h sock.c sock.h widget.c widget.h drivers.c drivers.h driver.c driver.h
-LCDd_LDADD = ../shared/libLCDstuff.a commands/libLCDcommands.a
+LCDd_LDADD = @ldap_libs@ ../shared/libLCDstuff.a commands/libLCDcommands.a
 LCDd_LDFLAGS = -rdynamic -uget_args
 INCLUDES = -I$(top_srcdir)

shared/Makefile.am

@@ -1,3 +1,6 @@
 noinst_LIBRARIES = libLCDstuff.a
 libLCDstuff_a_SOURCES = LL.c LL.h sockets.c sockets.h str.c str.h configfile.c configfile.h debug.h report.c report.h snprintf.c snprintf.h
-INCLUDES = -I$(top_srcdir)
+
+INCLUDES = @ldap_includes@ -I$(top_srcdir)
+
+EXTRA_DIST = Makefile.in

shared/configfile.c

@@ -6,17 +6,24 @@
  * COPYING file distributed with this package.
  *
  * Copyright (c) 2001, Joris Robijn
+ *           (c) 2003, Rene Wagner
  *
  *
  * Defines routines to read ini-file-like files.
+ * Optionally retrieves settings from an LDAP directory (OpenLDAP 2.1.x)
  */
 
+#include "config.h"
 
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <stdlib.h>
 
+#ifdef WITH_LDAP_SUPPORT
+# include <ldap.h>
+#endif /* WITH_LDAP_SUPPORT */
+
 #include "shared/report.h"
 
 
@@ -43,6 +50,20 @@ key * find_key( section * s, char * keyname, int skip );
 key * add_key( section * s, char * keyname, char * value );
 int process_config( section ** current_section, char (*get_next_char)(), char modify_section_allowed, char * source_descr );
 
+#ifdef WITH_LDAP_SUPPORT
+int connect_to_ldap(void);
+
+static LDAP * ld = NULL;
+int use_ldap=0;
+
+static char * ldap_host=NULL, * ldap_base_dn=NULL;
+int ldap_port;
+
+/* not supported for now
+ * char ldap_user[255] = "",
+ *      ldap_pwd[255]  = "";
+ */
+#endif /* WITH_LDAP_SUPPORT */
 
 /**** EXTERNAL FUNCTIONS ****/
 
@@ -56,6 +77,41 @@ int config_read_file( char *filename )
 	int pos=0;
 	section * curr_section = NULL;
 
+#ifdef WITH_LDAP_SUPPORT
+	LDAPURLDesc * url = NULL;
+	int retval;
+#endif /* WITH_LDAP_SUPPORT */   
+
+	report( RPT_NOTICE, "Using Configuration File: %s", filename);
+
+#ifdef WITH_LDAP_SUPPORT
+	if (ldap_is_ldap_url( filename )) {
+		use_ldap=1;
+		
+		if (0 != (retval = ldap_url_parse( filename, &url))) {
+			report( RPT_ERR, "Errors parsing LDAP URL %s: %s", filename, ldap_err2string(retval));
+			ldap_free_urldesc(url);
+			return (-1);
+		}
+
+		ldap_host=strdup(url->lud_host);
+		ldap_port=url->lud_port;
+		report( RPT_INFO, "Using LDAP server: %s:%d", ldap_host, ldap_port);
+
+		ldap_base_dn=strdup(url->lud_dn);
+		report( RPT_INFO, "Using LDAP base DN: %s", ldap_base_dn);
+
+		ldap_free_urldesc(url);
+
+		if (connect_to_ldap() < 0 ) {
+			debug( RPT_DEBUG, "connect_to_ldap returned errors.");
+			return (-1);
+		}
+
+		return 0;
+	}
+#endif /* WITH_LDAP_SUPPORT */ 
+
 	/* We use a nested fuction to transfer the characters from buffer to parser*/
 	char get_next_char() {
 		if( pos>=bytesread ) {
@@ -258,10 +314,94 @@ void config_clear()
 
 /**** INTERNAL FUNCTIONS ****/
 
+#ifdef WITH_LDAP_SUPPORT
+int
+connect_to_ldap (void)
+{
+	int retval;
+	LDAPMessage * res;
+
+	debug( RPT_INFO, "Connecting to LDAP server: %s:%d", ldap_host, ldap_port);
+
+	if (!(ld = ldap_init(ldap_host, ldap_port))) {
+		report(RPT_ERR, "LDAP session could not be initialized.");
+		return (-1);
+	}
+
+/*****************************************************
+ * disabled unless you really have a DN/pwd to bind to
+ * WARNING: LCDd should not have LDAP write access!!
+ *
+ *	if (LDAP_SUCCESS != (retval = ldap_simple_bind_s (ld, ldap_user, ldap_pwd))) {
+ *		report (RPT_ERR, "LDAP login on %s:%d failed: %s", ldap_host, ldap_port, ldap_err2string (retval));
+ *		ldap_unbind (ld);
+ *		ld = NULL;
+ *		
+ *		return (-1);
+ *	}
+ *	fprintf(stderr, "LDAP login successful on %s:%d\n", ldap_host, ldap_port);
+ ********************************************************/
+ 
+	/* check for the existence of the config object... */
+	if (LDAP_SUCCESS != (retval = ldap_search_s (ld, ldap_base_dn, LDAP_SCOPE_BASE, "objectClass=lcdprocConfig", NULL, 0, &res))) {
+		report( RPT_ERR, "Could not access LDAP server on %s:%d", ldap_host, ldap_port);
+		return (-1);
+	}
+	if (0 == ldap_count_entries(ld, res)) {
+		report( RPT_ERR, "No configuration object found in LDAP at: %s", ldap_base_dn);
+		return (-1);
+	}
+	debug( RPT_DEBUG, "Configuration LDAP object found.");
+	return 0;
+}
+
+#define BUFSIZE 255
+#endif /* WITH_LDAP_SUPPORT */
+
 section * find_section( char * sectionname )
 {
 	section * s;
 
+#ifdef WITH_LDAP_SUPPORT
+	LDAPMessage * res;
+	int retval;
+	char *filter=NULL;
+
+	if (use_ldap) {
+		debug( RPT_DEBUG, "Searching LDAP for section [%s]", sectionname);
+		if (NULL == (filter = malloc(BUFSIZE))){
+			report( RPT_ERR, "Could not allocate memory in find_section()");
+			return NULL;
+		}
+		strcpy(filter, "cn=");
+		strncat(filter, sectionname, BUFSIZE);
+		if (LDAP_SUCCESS != (retval = ldap_search_s (ld, ldap_base_dn, LDAP_SCOPE_ONELEVEL, filter, NULL, 0, &res))) {
+			if (NULL != filter) {
+				free(filter);
+				filter=NULL;
+			}
+			ldap_msgfree(res);
+			report( RPT_ERR, "Could not access LDAP server on %s:%d", ldap_host, ldap_port);
+			return NULL;
+		}
+		if (NULL != filter) {
+			free(filter);
+			filter=NULL;
+		}
+		if (0 == ldap_count_entries( ld, res )) {
+			debug( RPT_DEBUG, "Section [%s] not found in LDAP.", sectionname);
+			return NULL;
+		}
+		ldap_msgfree(res);
+		debug( RPT_DEBUG, "Found section [%s] in LDAP", sectionname);
+		s = (section*) malloc( sizeof( section ));
+		s->name=strdup( sectionname );
+		s->first_key = NULL;
+		s->next_section = NULL;
+		return s;
+	}
+#endif /* WITH_LDAP_SUPPORT */
+
 	for( s=first_section; s; s=s->next_section ) {
 		if( strcasecmp( s->name, sectionname ) == 0 ) {
 			return s;
@@ -292,9 +432,104 @@ key * find_key( section * s, char * keyname, int skip )
 	int count = 0;
 	key * last_key = NULL;
 
+#ifdef WITH_LDAP_SUPPORT	
+	LDAPMessage * res;
+	LDAPMessage * entry;
+	int retval;
+	char *buf=NULL;
+	char **vals;
+#endif /* WITH_LDAP_SUPPORT */
+
 	/* Check for NULL section*/
 	if(!s) return NULL;
 
+#ifdef WITH_LDAP_SUPPORT
+	if (use_ldap) {
+		debug( RPT_DEBUG, "Searching LDAP for key '%s' in section [%s] skipping %d entries.", keyname, s->name, skip);
+
+		if (NULL == (buf = malloc(BUFSIZE))){
+			report (RPT_ERR, "Could not allocate memory in find_key().");
+		}
+		strcpy(buf, "cn=");
+		strncat(buf, s->name, BUFSIZE);
+		if (LDAP_SUCCESS != (retval = ldap_search_s (ld, ldap_base_dn, LDAP_SCOPE_ONELEVEL, buf, NULL, 0, &res))) {
+			if (NULL != buf) {
+				free(buf);
+				buf=NULL;
+			}
+			ldap_msgfree(res);
+			report( RPT_ERR, "Could not access LDAP server on %s:%d", ldap_host, ldap_port);
+			return NULL;
+		}
+		if (NULL == (entry = ldap_first_entry( ld, res ))) {
+			debug( RPT_DEBUG, "Section [%s] not found in LDAP.", s->name);
+			if (NULL != buf) {
+				free(buf);
+				buf=NULL;
+			}
+			/* DON'T enable the following
+			 * ldap_msgfree(entry);
+			 * ldap_msgfree below does that already
+			 */
+			ldap_msgfree(res);
+			return NULL;
+		}
+
+		
+		strcpy(buf, "lcdproc");
+		strncat(buf, keyname, BUFSIZE);
+		/* debug( RPT_DEBUG, "Key name translated to attribute name: %s", buf); */
+		vals = ldap_get_values (ld, entry, buf);
+		
+		if (skip+1 > ldap_count_values (vals)) {
+			debug( RPT_DEBUG, "No such entry found.");
+			if (NULL != buf) {
+				free(buf);
+				buf=NULL;
+			}
+			ldap_value_free(vals);
+			/* DON'T enable the following
+			 * ldap_msgfree(entry);
+			 * ldap_msgfree below does that already
+			 */
+			ldap_msgfree(res);
+			return NULL;
+		}
+		/* DON'T enable the following
+		 * ldap_msgfree(entry);
+		 * ldap_msgfree below does that already
+		 */
+		ldap_msgfree(res);
+		if (vals && vals[skip]) {
+			if (NULL != buf) {
+				free(buf);
+				buf=NULL;
+			}
+			buf=strdup(vals[skip]);
+			debug( RPT_DEBUG, "Entry found. Value is: %s", buf);
+			ldap_value_free (vals);
+						
+			k=(key*) malloc( sizeof( key ));
+			k->name = strdup( keyname );
+			k->value = strdup( buf );
+			k->next_key = NULL;
+			
+			if (NULL != buf) {
+				free(buf);
+				buf=NULL;
+			}
+			return k;
+		} 
+		report( RPT_ERR, "LDAP server encountered errors.");
+		ldap_value_free (vals);
+		if (NULL != buf) {
+			free(buf);
+			buf=NULL;
+		}
+		return NULL;
+	}
+#endif /* WITH_LDAP_SUPPORT */
+
 	for( k=s->first_key; k; k=k->next_key ) {
 
 		/* Did we find the right key ?*/