added support for older MIT kerberos versions

- make the build of the locator plugin optional
- added a man page for the locator plugin
- use krb5.h if krb5/krb5.h cannot be found
- added alternatives for missing functions
- set -DDBUS_API_SUBJECT_TO_CHANGE if libdbus version
  is lesser than 1.0.0

8 files changed, 177 insertions, 12 deletions

diff --git a/contrib/sssd.spec.in b/contrib/sssd.spec.in
index 408d44936..786b2e9e0 100644
--- a/contrib/sssd.spec.in
+++ b/contrib/sssd.spec.in
@@ -92,10 +92,16 @@ rm -f \
     $RPM_BUILD_ROOT/%{_libdir}/krb5/plugins/libkrb5/sssd_krb5_locator_plugin.la \
     $RPM_BUILD_ROOT/%{python_sitearch}/pysss.la
 
+touch locator.filelist
+if test -e $RPM_BUILD_ROOT/%{_libdir}/krb5/plugins/libkrb5/sssd_krb5_locator_plugin.so
+then
+    echo %{_libdir}/krb5/plugins/libkrb5/sssd_krb5_locator_plugin.so > locator.filelist
+fi
+
 %clean
 rm -rf $RPM_BUILD_ROOT
 
-%files
+%files -f locator.filelist
 %defattr(-,root,root,-)
 %doc COPYING
 %{_initrddir}/%{name}
@@ -109,7 +115,6 @@ rm -rf $RPM_BUILD_ROOT
 %{_libexecdir}/%{servicename}/
 %{_libdir}/%{name}/
 %{_libdir}/ldb/memberof.so
-%{_libdir}/krb5/plugins/libkrb5/*
 %dir %{sssdstatedir}
 %attr(700,root,root) %dir %{dbpath}
 %attr(755,root,root) %dir %{pipepath}
diff --git a/server/Makefile.am b/server/Makefile.am
index 6ed405a5b..41eeefb42 100644
--- a/server/Makefile.am
+++ b/server/Makefile.am
@@ -7,7 +7,9 @@ builddir ?= .
 sssdlibexecdir = $(libexecdir)/sssd
 sssdlibdir = $(libdir)/sssd
 ldblibdir = $(libdir)/ldb
+if BUILD_KRB5_LOCATOR_PLUGIN
 krb5plugindir = @krb5pluginpath@
+endif
 sssdconfdir = $(sysconfdir)/sssd
 dbusintrospectdir = $(datarootdir)/sssd/introspect
 dbuspolicydir = $(sysconfdir)/dbus-1/system.d
@@ -78,8 +80,10 @@ sssdlib_LTLIBRARIES = \
 ldblib_LTLIBRARIES = \
     memberof.la
 
+if BUILD_KRB5_LOCATOR_PLUGIN
 krb5plugin_LTLIBRARIES = \
     sssd_krb5_locator_plugin.la
+endif
 
 noinst_LTLIBRARIES = \
     libsss_crypt.la
@@ -203,8 +207,8 @@ SSSD_LIBS = \
     $(COLLECTION_LIBS) \
     $(DHASH_LIBS) \
     $(REPLACE_LIBS) \
-    $(NSS_LIBS) \
-    libsss_crypt.la
+    libsss_crypt.la \
+    $(NSS_LIBS)
 
 PYTHON_BINDINGS_LIBS = \
     $(TALLOC_LIBS) \
@@ -464,6 +468,7 @@ memberof_la_LDFLAGS = \
     -avoid-version \
     -module
 
+if BUILD_KRB5_LOCATOR_PLUGIN
 sssd_krb5_locator_plugin_la_SOURCES = \
     krb5_plugin/sssd_krb5_locator_plugin.c
 sssd_krb5_locator_plugin_la_CFLAGS = \
@@ -472,6 +477,7 @@ sssd_krb5_locator_plugin_la_CFLAGS = \
 sssd_krb5_locator_plugin_la_LDFLAGS = \
     -avoid-version \
     -module
+endif
 
 if BUILD_PYTHON_BINDINGS
 pysss_la_SOURCES = \
@@ -501,7 +507,8 @@ XSLTPROC_FLAGS = --catalogs --xinclude --nonet
 
 dist_man_MANS = man/sss_useradd.8 man/sss_userdel.8 man/sss_usermod.8 \
 		man/sss_groupadd.8 man/sss_groupdel.8 man/sss_groupmod.8 \
-		man/sssd.8 man/sssd.conf.5 man/sssd-ldap.5 man/sssd-krb5.5
+		man/sssd.8 man/sssd.conf.5 man/sssd-ldap.5 man/sssd-krb5.5 \
+		man/sssd_krb5_locator_plugin.8
 
 SUFFIXES = .1.xml .1 .3.xml .3 .5.xml .5 .8.xml .8
 .1.xml.1:
diff --git a/server/configure.ac b/server/configure.ac
index 475bdca6a..03d2885ac 100644
--- a/server/configure.ac
+++ b/server/configure.ac
@@ -67,6 +67,12 @@ m4_include([external/python.m4])
 m4_include([util/signal.m4])
 
 PKG_CHECK_MODULES([DBUS],[dbus-1])
+dnl if test -n "`$PKG_CONFIG --modversion dbus-1 | grep '^0\.'`" ; then
+if ! $PKG_CONFIG --atleast-version 1.0.0 dbus-1; then
+    DBUS_CFLAGS="$DBUS_CFLAGS -DDBUS_API_SUBJECT_TO_CHANGE"
+    AC_MSG_RESULT([setting -DDBUS_API_SUBJECT_TO_CHANGE])
+fi
+
 if test x$has_dbus != xno; then
     SAFE_LDFLAGS="$LDFLAGS"
     LDFLAGS="$DBUS_LIBS"
diff --git a/server/external/krb5.m4 b/server/external/krb5.m4
index 1ed5064a5..95cd386e2 100644
--- a/server/external/krb5.m4
+++ b/server/external/krb5.m4
@@ -9,3 +9,31 @@ if test -x "$KRB5_CONFIG"; then
 else
   AC_MSG_ERROR(no. Please install MIT kerberos devel package)
 fi
+
+SAVE_CFLAGS=$CFLAGS
+SAVE_LIBS=$LIBS
+CFLAGS="$CFLAGS $KRB5_CFLAGS"
+LIBS="$LIBS $KRB5_LIBS"
+AC_CHECK_HEADERS([krb5.h krb5/krb5.h])
+AC_CHECK_FUNCS([krb5_get_init_creds_opt_alloc krb5_get_error_message])
+CFLAGS=$SAVE_CFLAGS
+LIBS=$SAVE_LIBS
+
+if test x$ac_cv_header_krb5_h != xyes -a x$ac_cv_header_krb5_krb5_h != xyes
+then
+  AC_MSG_ERROR(you must have Kerberos 5 header files to build sssd)
+fi
+
+AC_ARG_ENABLE([krb5-locator-plugin],
+              [AS_HELP_STRING([--disable-krb5-locator-plugin],
+                              [do not build Kerberos locator plugin])],
+              [build_locator=$enableval],
+              [build_locator=yes])
+
+AC_CHECK_HEADER([krb5/locate_plugin.h],
+                [have_locate_plugin=yes],
+                [have_locate_plugin=no]
+                [AC_MSG_NOTICE([Kerberos locator plugin cannot be build])])
+AM_CONDITIONAL([BUILD_KRB5_LOCATOR_PLUGIN],
+               [test x$have_locate_plugin == xyes -a x$build_locator == xyes])
+
diff --git a/server/man/sssd_krb5_locator_plugin.8.xml b/server/man/sssd_krb5_locator_plugin.8.xml
new file mode 100644
index 000000000..6c60431ff
--- /dev/null
+++ b/server/man/sssd_krb5_locator_plugin.8.xml
@@ -0,0 +1,89 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE reference PUBLIC "-//OASIS//DTD DocBook V4.4//EN"
+"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
+<reference>
+<title>SSSD Manual pages</title>
+<refentry>
+    <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="include/upstream.xml" />
+
+    <refmeta>
+        <refentrytitle>sssd_krb5_locator_plugin</refentrytitle>
+        <manvolnum>8</manvolnum>
+    </refmeta>
+
+    <refnamediv id='name'>
+        <refname>sssd_krb5_locator_plugin</refname>
+        <refpurpose>the configuration file for SSSD</refpurpose>
+    </refnamediv>
+
+    <refsect1 id='description'>
+        <title>DESCRIPTION</title>
+        <para>
+            The Kerberos locator plugin
+            <command>sssd_krb5_locator_plugin</command> is used by the Kerberos
+            provider of
+            <citerefentry>
+                <refentrytitle>sssd</refentrytitle>
+                <manvolnum>8</manvolnum>
+            </citerefentry>
+            to tell the Kerberos libraries what Realm and which KDC to use.
+            Typically this is done in
+            <citerefentry>
+                <refentrytitle>krb5.conf</refentrytitle>
+                <manvolnum>5</manvolnum>
+            </citerefentry>
+            which is always read by the Kerberos libraries. To simplyfy the
+            configuration the Realm and the KDC can be defined in
+            <citerefentry>
+                <refentrytitle>sssd.conf</refentrytitle>
+                <manvolnum>5</manvolnum>
+            </citerefentry>
+            as described in
+            <citerefentry>
+                <refentrytitle>sssd-krb5.conf</refentrytitle>
+                <manvolnum>5</manvolnum>
+            </citerefentry>
+        </para>
+        <para>
+            <citerefentry>
+                <refentrytitle>sssd</refentrytitle>
+                <manvolnum>8</manvolnum>
+            </citerefentry>
+            puts the Realm and the name or IP address of the KDC into the
+            enviroment variables SSSD_KRB5_REALM and SSSD_KRB5_KDC respectively.
+            When <command>sssd_krb5_locator_plugin</command> is called by the
+            kerberos libraries it reads and evaluates these variable and returns
+            them to the libraries.
+        </para>
+    </refsect1>
+
+    <refsect1 id='notes'>
+        <title>NOTES</title>
+        <para>
+            Not all Kerberos implementations support the use of plugins. If
+            <command>sssd_krb5_locator_plugin</command> is not available on
+            your system you have to edit /etc/krb5.conf to reflect your
+            Kerberos setup.
+        </para>
+        <para>
+            If the enviroment variable SSSD_KRB5_LOCATOR_DEBUG is set to any
+            value debug messages will be sent to stderr.
+        </para>
+    </refsect1>
+
+    <refsect1 id='see_also'>
+        <title>SEE ALSO</title>
+        <para>
+            <citerefentry>
+                <refentrytitle>sssd-krb5</refentrytitle><manvolnum>5</manvolnum>
+            </citerefentry>,
+            <citerefentry>
+                <refentrytitle>sssd.conf</refentrytitle><manvolnum>5</manvolnum>
+            </citerefentry>,
+            <citerefentry>
+                <refentrytitle>sssd</refentrytitle><manvolnum>8</manvolnum>
+            </citerefentry>
+        </para>
+    </refsect1>
+</refentry>
+</reference>
diff --git a/server/providers/krb5/krb5_auth.c b/server/providers/krb5/krb5_auth.c
index 03e790322..631f70862 100644
--- a/server/providers/krb5/krb5_auth.c
+++ b/server/providers/krb5/krb5_auth.c
@@ -22,10 +22,9 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
 #include <errno.h>
 #include <sys/time.h>
-#include <krb5/krb5.h>
+
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <unistd.h>
diff --git a/server/providers/krb5/krb5_auth.h b/server/providers/krb5/krb5_auth.h
index 4e65d9fc2..9a7807e8a 100644
--- a/server/providers/krb5/krb5_auth.h
+++ b/server/providers/krb5/krb5_auth.h
@@ -26,8 +26,15 @@
 #ifndef __KRB5_AUTH_H__
 #define __KRB5_AUTH_H__
 
+#include "config.h"
+
 #include <stdbool.h>
+
+#ifdef HAVE_KRB5_KRB5_H
 #include <krb5/krb5.h>
+#else
+#include <krb5.h>
+#endif
 
 #define MAX_CHILD_MSG_SIZE 255
 #define CCACHE_ENV_NAME "KRB5CCNAME"
@@ -79,9 +86,6 @@ struct krb5_ctx {
 
     action_type action;
 
-    int num_pa_opts;
-    krb5_gic_opt_pa_data *pa_opts;
-
     char *kdcip;
     char *realm;
     bool try_simple_upn;
diff --git a/server/providers/krb5/krb5_child.c b/server/providers/krb5/krb5_child.c
index 3673c7457..4f3a62c65 100644
--- a/server/providers/krb5/krb5_child.c
+++ b/server/providers/krb5/krb5_child.c
@@ -22,7 +22,6 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <krb5/krb5.h>
 #include <sys/types.h>
 #include <unistd.h>
 #include <sys/stat.h>
@@ -53,6 +52,7 @@ struct krb5_req {
     char *ccname;
 };
 
+#ifdef HAVE_KRB5_GET_ERROR_MESSAGE
 static krb5_context krb5_error_ctx;
 static const char *__krb5_error_msg;
 #define KRB5_DEBUG(level, krb5_error) do { \
@@ -60,6 +60,11 @@ static const char *__krb5_error_msg;
     DEBUG(level, ("%d: [%d][%s]\n", __LINE__, krb5_error, __krb5_error_msg)); \
     krb5_free_error_message(krb5_error_ctx, __krb5_error_msg); \
 } while(0);
+#else
+#define KRB5_DEBUG(level, krb5_error) do { \
+    DEBUG(level, ("%d: kerberos error [%d]\n", __LINE__, krb5_error)); \
+} while(0);
+#endif
 
 struct response {
     size_t max_size;
@@ -138,6 +143,7 @@ static struct response *prepare_response_message(struct krb5_req *kr,
         ret = pack_response_packet(resp, PAM_SUCCESS, PAM_ENV_ITEM, msg);
         talloc_zfree(msg);
     } else {
+#ifdef HAVE_KRB5_GET_ERROR_MESSAGE
         krb5_msg = krb5_get_error_message(krb5_error_ctx, kerr);
         if (krb5_msg == NULL) {
             DEBUG(1, ("krb5_get_error_message failed.\n"));
@@ -146,6 +152,11 @@ static struct response *prepare_response_message(struct krb5_req *kr,
 
         ret = pack_response_packet(resp, pam_status, PAM_USER_INFO, krb5_msg);
         krb5_free_error_message(krb5_error_ctx, krb5_msg);
+#else
+        msg = talloc_asprintf(kr, "Kerberos error [%d]", kerr);
+        ret = pack_response_packet(resp, pam_status, PAM_USER_INFO, msg);
+        talloc_zfree(msg);
+#endif
     }
 
     if (ret != EOK) {
@@ -441,8 +452,14 @@ static int krb5_cleanup(void *ptr)
     struct krb5_req *kr = talloc_get_type(ptr, struct krb5_req);
     if (kr == NULL) return EOK;
 
-    if (kr->options != NULL)
+    if (kr->options != NULL) {
+#ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_ALLOC
         krb5_get_init_creds_opt_free(kr->ctx, kr->options);
+#else
+        free(kr->options);
+#endif
+    }
+
     if (kr->creds != NULL) {
         krb5_free_cred_contents(kr->ctx, kr->creds);
         krb5_free_creds(kr->ctx, kr->creds);
@@ -539,11 +556,21 @@ static int krb5_setup(struct pam_data *pd, const char *user_princ_str,
         goto failed;
     }
 
+#ifdef HAVE_KRB5_GET_INIT_CREDS_OPT_ALLOC
     kerr = krb5_get_init_creds_opt_alloc(kr->ctx, &kr->options);
     if (kerr != 0) {
         KRB5_DEBUG(1, kerr);
         goto failed;
     }
+#else
+    kr->options = calloc(1, sizeof(krb5_get_init_creds_opt));
+    if (kr->options == NULL) {
+        DEBUG(1, ("calloc failed.\n"));
+        kerr = ENOMEM;
+        goto failed;
+    }
+    krb5_get_init_creds_opt_init(&kr->options);
+#endif
 
 /* TODO: set options, e.g.
  *  krb5_get_init_creds_opt_set_tkt_life