* kdb_dbm.c: Ditch DB_OPENCLOSE conditionals, and fix the real

 	problem.  Like the policy db, the main db is now opened on first
 	lock and closed on last unlock.
	Set db_dbm_ctx to NULL after closing it, to help detect dangling
	references.
	(krb5_dbm_db_put_principal, krb5_dbm_db_delete_principal):
 	KDBM_STORE can fail (in case of database corruption, for example)
 	*without* causing errno to be set.  If errno is zero, use
 	KRB5_KDB_DB_CORRUPT instead. (If it is non-zero, it may still be
 	wrong, but at least something gets reported. This will be properly
	fixed by ditching KDBM_* altogether, and using the non-lossy db
	interfaces, so it's a good enough fix for now.)
	(krb5_dbm_db_rename): grab errno from rename *before*
 	calling krb5_dbm_db_end_update, to avoid "not a typewriter"
 	syndrome.
 	(krb5_dbm_db_unlock): only close on zero refcount.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@9400 dc483132-0cff-0310-8789-dd5450dbe970

diff --git a/src/lib/kdb/ChangeLog b/src/lib/kdb/ChangeLog
index 53acac4714f666b4948957427a6f38cf6c44fade..3f74707fbbfa8e79120a1c4bdd13a3a5d543b09c 100644 (file)
--- a/src/lib/kdb/ChangeLog
+++ b/src/lib/kdb/ChangeLog
@@ -1,3 +1,22 @@
+Tue Nov 12 23:41:55 1996  Mark Eichin <eichin@cygnus.com>
+
+       * kdb_dbm.c: Ditch DB_OPENCLOSE conditionals, and fix the real
+       problem.  Like the policy db, the main db is now opened on first
+       lock and closed on last unlock.  
+       Set db_dbm_ctx to NULL after closing it, to help detect dangling
+       references.
+       (krb5_dbm_db_put_principal, krb5_dbm_db_delete_principal):
+       KDBM_STORE can fail (in case of database corruption, for example)
+       *without* causing errno to be set.  If errno is zero, use
+       KRB5_KDB_DB_CORRUPT instead. (If it is non-zero, it may still be
+       wrong, but at least something gets reported. This will be properly
+       fixed by ditching KDBM_* altogether, and using the non-lossy db
+       interfaces, so it's a good enough fix for now.)
+       (krb5_dbm_db_rename): grab errno from rename *before*
+       calling krb5_dbm_db_end_update, to avoid "not a typewriter"
+       syndrome.
+       (krb5_dbm_db_unlock): only close on zero refcount.
+
 Mon Nov 11 20:21:02 1996  Mark Eichin  <eichin@cygnus.com>
 
        * kdb_cpw.c (add_key_pwd): set length to -1 so krb5_string_to_key

diff --git a/src/lib/kdb/kdb_dbm.c b/src/lib/kdb/kdb_dbm.c
index 6476734b213cd6ef62e99dc1ad4a8d907702adc3..a1dba73ee27dd064799b2464d74a9b7ae7f0568c 100644 (file)
--- a/src/lib/kdb/kdb_dbm.c
+++ b/src/lib/kdb/kdb_dbm.c
@@ -22,8 +22,6 @@
  * 
  */
 
-#define DB_OPENCLOSE
-
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
@@ -251,13 +249,7 @@ krb5_dbm_db_init(context)
        return(retval);
 
     db_ctx = context->db_context;
-#ifdef DB_OPENCLOSE
     db_ctx->db_dbm_ctx = NULL;
-#else
-    if (!(db_ctx->db_dbm_ctx = (DBM *)KDBM_OPEN(db_ctx, db_ctx->db_name, 
-                                               O_RDWR, 0600)))
-       return errno;
-#endif
 
     if (!(filename = gen_dbsuffix (db_ctx->db_name, KDBM_LOCK_EXT(db_ctx))))
        return ENOMEM;
@@ -281,9 +273,6 @@ krb5_dbm_db_init(context)
     return 0;
     
 err_out:
-#ifndef DB_OPENCLOSE
-    KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-#endif
     db_ctx->db_dbm_ctx = (DBM *) NULL;
     k5dbm_clear_context(db_ctx);
     return (retval);
@@ -303,17 +292,6 @@ krb5_dbm_db_fini(context)
     db_ctx = (krb5_db_context *) context->db_context;
 
     if (k5dbm_inited(context)) {
-#ifndef DB_OPENCLOSE
-       if (db_ctx->db_dbm_ctx) {
-           /* dbm_close returns void, but it is possible for there to be an
-              error in close().  Possible changes to this routine: check errno
-              on return from dbm_close(), call fsync on the database file
-              descriptors.  */
-           KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-           db_ctx->db_dbm_ctx = NULL;
-       }
-#endif
-
        if (close(db_ctx->db_lf_file))
            retval = errno;
        else
@@ -541,7 +519,6 @@ krb5_dbm_db_lock(context, mode)
     if ((retval = krb5_dbm_db_get_age(context, NULL, &mod_time)))
        goto lock_error;
 
-#ifdef DB_OPENCLOSE
     if ((db = KDBM_OPEN(db_ctx, db_ctx->db_name,
                        mode == KRB5_LOCKMODE_SHARED ? O_RDONLY : O_RDWR,
                        0600))) {
@@ -551,18 +528,6 @@ krb5_dbm_db_lock(context, mode)
         retval = errno;
         goto lock_error;
     }
-#else
-    if (mod_time != db_ctx->db_lf_time) {
-       KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-       if ((db = KDBM_OPEN(db_ctx, db_ctx->db_name, O_RDWR, 0600))) {
-           db_ctx->db_lf_time = mod_time;
-           db_ctx->db_dbm_ctx = db;
-       } else {
-           retval = errno;
-           goto lock_error;
-       }
-    }
-#endif
 
     db_ctx->db_lock_mode = mode;
     db_ctx->db_locks_held++;
@@ -589,11 +554,10 @@ krb5_dbm_db_unlock(context)
     if (!db_ctx->db_locks_held)                /* lock already unlocked */
        return KRB5_KDB_NOTLOCKED;
 
-#ifdef DB_OPENCLOSE
+    if (--(db_ctx->db_locks_held) == 0) {
     KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-#endif
+       db_ctx->db_dbm_ctx = NULL;
 
-    if (--(db_ctx->db_locks_held) == 0) {
        retval = krb5_lock_file(context, db_ctx->db_lf_file,
                                KRB5_LOCKMODE_UNLOCK);
        db_ctx->db_lock_mode = 0;
@@ -808,7 +772,7 @@ krb5_dbm_db_rename(context, from, to)
        db_ctx = (krb5_db_context *) context->db_context;
 
        /*
-        * Create the database if it does not already exists; the
+        * Create the database if it does not already exist; the
         * files must exist because krb5_dbm_db_lock, called below,
         * will fail otherwise.
         */
@@ -918,12 +882,12 @@ krb5_dbm_db_rename(context, from, to)
                        (void) unlink(fromok);
                   retval = krb5_dbm_db_end_update(context);
              } else {
-                  (void) krb5_dbm_db_end_update(context);
                   retval = errno;
+                  (void) krb5_dbm_db_end_update(context);
              }
         } else {
-             (void) krb5_dbm_db_end_update(context);
              retval = errno;
+             (void) krb5_dbm_db_end_update(context);
         }
     }
     
@@ -1073,20 +1037,8 @@ krb5_dbm_db_put_principal(context, entries, nentries)
            break;
        }
        if (KDBM_STORE(db_ctx, db_ctx->db_dbm_ctx, key, contents, DBM_REPLACE))
-           retval = errno;
-#ifndef DB_OPENCLOSE
-       else {
-           DBM *db;
+           retval = errno?errno:KRB5_KDB_DB_CORRUPT;
 
-           KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-           if ((db = KDBM_OPEN(db_ctx, db_ctx->db_name, O_RDWR, 0600))) {
-               db_ctx->db_dbm_ctx = db;
-               retval = 0;
-           }
-           else
-               retval = errno;
-       }
-#endif
        krb5_free_princ_contents(context, &contents);
        krb5_free_princ_dbmkey(context, &key);
        if (retval)
@@ -1156,23 +1108,10 @@ krb5_dbm_db_delete_principal(context, searchfor, nentries)
            goto cleancontents;
 
        if (KDBM_STORE(db_ctx, db, key, contents2, DBM_REPLACE))
-           retval = errno;
+           retval = errno?errno:KRB5_KDB_DB_CORRUPT;
        else {
            if (KDBM_DELETE(db_ctx, db, key))
-               retval = errno;
-#ifndef DB_OPENCLOSE
-           else {
-               DBM *db;
-
-               KDBM_CLOSE(db_ctx, db_ctx->db_dbm_ctx);
-               if ((db = KDBM_OPEN(db_ctx, db_ctx->db_name, O_RDWR, 0600))) {
-                   db_ctx->db_dbm_ctx = db;
-                   retval = 0;
-               }
-               else
-                   retval = errno;
-           }
-#endif
+               retval = errno?errno:KRB5_KDB_DB_CORRUPT;
        }
        krb5_free_princ_contents(context, &contents2);
     cleancontents: