third_party/heimdal: Introduce macro for common plugin structure elements

Heimdal's HDB plugin interface, and hence Samba's KDC that depends upon
it, doesn't work on 32-bit builds due to structure fields being arranged
in the wrong order. This problem presents itself in the form of
segmentation faults on 32-bit systems, but goes unnoticed on 64-bit
builds thanks to extra structure padding absorbing the errant fields.

This commit reorders the HDB plugin structure fields to prevent crashes
and introduces a common macro to ensure every plugin presents a
consistent interface.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15110

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

4 files changed, 27 insertions, 28 deletions

diff --git a/third_party/heimdal/lib/hdb/hdb-ldap.c b/third_party/heimdal/lib/hdb/hdb-ldap.c
index 6a2876c51d7..5cd097f5b6b 100644
--- a/third_party/heimdal/lib/hdb/hdb-ldap.c
+++ b/third_party/heimdal/lib/hdb/hdb-ldap.c
@@ -2097,9 +2097,9 @@ fini(void *ctx)
 
 struct hdb_method hdb_ldap_interface = {
     HDB_INTERFACE_VERSION,
-    0 /*is_file_based*/, 0 /*can_taste*/,
     init,
     fini,
+    0 /*is_file_based*/, 0 /*can_taste*/,
     "ldap",
     hdb_ldap_create
 };
@@ -2108,6 +2108,7 @@ struct hdb_method hdb_ldapi_interface = {
     HDB_INTERFACE_VERSION,
     init,
     fini,
+    0 /*is_file_based*/, 0 /*can_taste*/,
     "ldapi",
     hdb_ldapi_create
 };
diff --git a/third_party/heimdal/lib/hdb/hdb.c b/third_party/heimdal/lib/hdb/hdb.c
index 56c403842e6..171ba9e3fd3 100644
--- a/third_party/heimdal/lib/hdb/hdb.c
+++ b/third_party/heimdal/lib/hdb/hdb.c
@@ -66,41 +66,41 @@ const int hdb_interface_version = HDB_INTERFACE_VERSION;
 static struct hdb_method methods[] = {
     /* "db:" should be db3 if we have db3, or db1 if we have db1 */
 #if HAVE_DB3
-    { HDB_INTERFACE_VERSION, 1 /*is_file_based*/, 1 /*can_taste*/, NULL, NULL,
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1 /*is_file_based*/, 1 /*can_taste*/,
                                                "db:",	hdb_db3_create},
 #elif HAVE_DB1
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "db:",	hdb_db1_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "db:",	hdb_db1_create},
 #endif
 #if HAVE_DB1
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "db1:",	hdb_db1_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "db1:",	hdb_db1_create},
 #endif
 #if HAVE_DB3
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "db3:",	hdb_db3_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "db3:",	hdb_db3_create},
 #endif
 #if HAVE_DB1
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "mit-db:",	hdb_mitdb_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "mit-db:",	hdb_mitdb_create},
 #endif
 #if HAVE_LMDB
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "mdb:",	hdb_mdb_create},
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "lmdb:",	hdb_mdb_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "mdb:",	hdb_mdb_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "lmdb:",	hdb_mdb_create},
 #endif
 #if HAVE_NDBM
-    { HDB_INTERFACE_VERSION, 1, 0, NULL, NULL, "ndbm:",	hdb_ndbm_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 0, "ndbm:",	hdb_ndbm_create},
 #endif
 #ifdef HAVE_SQLITE3
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "sqlite:", hdb_sqlite_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "sqlite:", hdb_sqlite_create},
 #endif
     /* The keytab interface can't use its hdb_open() method to "taste" a DB */
-    { HDB_INTERFACE_VERSION, 1, 0, NULL, NULL, "keytab:",	hdb_keytab_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 0, "keytab:",	hdb_keytab_create},
     /* The rest are not file-based */
 #if defined(OPENLDAP) && !defined(OPENLDAP_MODULE)
-    { HDB_INTERFACE_VERSION, 0, 0, NULL, NULL, "ldap:",	hdb_ldap_create},
-    { HDB_INTERFACE_VERSION, 0, 0, NULL, NULL, "ldapi:",	hdb_ldapi_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 0, 0, "ldap:",	hdb_ldap_create},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 0, 0, "ldapi:",	hdb_ldapi_create},
 #elif defined(OPENLDAP)
-    { HDB_INTERFACE_VERSION, 0, 0, NULL, NULL, "ldap:",	NULL},
-    { HDB_INTERFACE_VERSION, 0, 0, NULL, NULL, "ldapi:", NULL},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 0, 0, "ldap:",	NULL},
+    { HDB_INTERFACE_VERSION, NULL, NULL, 0, 0, "ldapi:", NULL},
 #endif
-    { 0, 0, 0, NULL, NULL, NULL, NULL}
+    { 0, NULL, NULL, 0, 0, NULL, NULL}
 };
 
 /**
@@ -494,19 +494,19 @@ hdb_init_db(krb5_context context, HDB *db)
  */
 #if defined(HAVE_LMDB)
 static struct hdb_method default_dbmethod =
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "", hdb_mdb_create };
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "", hdb_mdb_create };
 #elif defined(HAVE_DB3)
 static struct hdb_method default_dbmethod =
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "", hdb_db3_create };
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "", hdb_db3_create };
 #elif defined(HAVE_DB1)
 static struct hdb_method default_dbmethod =
-    { HDB_INTERFACE_VERSION, 1, 1, NULL, NULL, "", hdb_db1_create };
+    { HDB_INTERFACE_VERSION, NULL, NULL, 1, 1, "", hdb_db1_create };
 #elif defined(HAVE_NDBM)
 static struct hdb_method default_dbmethod =
-    { HDB_INTERFACE_VERSION, 0, 1, NULL, NULL, "", hdb_ndbm_create };
+    { HDB_INTERFACE_VERSION, NULL, NULL, 0, 1, "", hdb_ndbm_create };
 #else
 static struct hdb_method default_dbmethod =
-    { 0, 0, 0, NULL, NULL, NULL, NULL};
+    { 0, NULL, NULL, 0, 0, NULL, NULL};
 #endif
 
 static int
diff --git a/third_party/heimdal/lib/hdb/hdb.h b/third_party/heimdal/lib/hdb/hdb.h
index 0f2c92151e5..2a3d1c4bb8c 100644
--- a/third_party/heimdal/lib/hdb/hdb.h
+++ b/third_party/heimdal/lib/hdb/hdb.h
@@ -307,11 +307,9 @@ typedef struct HDB {
 #define HDB_INTERFACE_VERSION	11
 
 struct hdb_method {
-    int			version;
+    HEIM_PLUGIN_FTABLE_COMMON_ELEMENTS(krb5_context);
     unsigned int	is_file_based:1;
     unsigned int	can_taste:1;
-    krb5_error_code	(*init)(krb5_context, void **);
-    void		(*fini)(void *);
     const char *prefix;
     krb5_error_code (*create)(krb5_context, HDB **, const char *filename);
 };
diff --git a/third_party/heimdal/lib/hdb/test_namespace.c b/third_party/heimdal/lib/hdb/test_namespace.c
index a4c44ba190e..f9b4cdbdde8 100644
--- a/third_party/heimdal/lib/hdb/test_namespace.c
+++ b/third_party/heimdal/lib/hdb/test_namespace.c
@@ -243,17 +243,17 @@ struct hdb_method hdb_test =
 #ifdef WIN32
     /* Not c99 */
     HDB_INTERFACE_VERSION,
-    1 /*is_file_based*/, 1 /*can_taste*/,
     hdb_test_init,
     hdb_test_fini,
+    1 /*is_file_based*/, 1 /*can_taste*/,
     "test",
     hdb_test_create
 #else
-    .version = HDB_INTERFACE_VERSION,
-    .is_file_based = 1,
-    .can_taste = 1,
+    .minor_version = HDB_INTERFACE_VERSION,
     .init = hdb_test_init,
     .fini = hdb_test_fini,
+    .is_file_based = 1,
+    .can_taste = 1,
     .prefix = "test",
     .create = hdb_test_create
 #endif