From 727b20ac9b25ebe4ff37d68f88a6a260d5fe2535 Mon Sep 17 00:00:00 2001 From: Jeremy Allison Date: Wed, 18 Mar 2009 14:31:56 -0700 Subject: [PATCH] Fix bug #6195 - Migrating from 3.0.x to 3.3.x can fail to update passdb.tdb correctly. This is a really nasty one to fix as in order to successfully update the passdb.tdb we must do the equivalent of a tdbbackup to move to the new hash values before we do the upgrade. Jeremy. (cherry picked from commit a549aee12f33dc91f0cc32612516025eb212fb66) --- source/Makefile.in | 10 +-- source/passdb/pdb_tdb.c | 215 ++++++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 206 insertions(+), 19 deletions(-) diff --git a/source/Makefile.in b/source/Makefile.in index e160a99ab73..988ca2c7341 100644 --- a/source/Makefile.in +++ b/source/Makefile.in @@ -575,7 +575,7 @@ PASSDB_OBJ = $(PASSDB_GET_SET_OBJ) passdb/passdb.o passdb/pdb_interface.o \ passdb/util_unixsids.o passdb/lookup_sid.o \ passdb/login_cache.o @PDB_STATIC@ \ lib/account_pol.o $(PRIVILEGES_OBJ) \ - lib/util_nscd.o lib/winbind_util.o + lib/util_nscd.o lib/winbind_util.o $(SERVER_MUTEX_OBJ) DEVEL_HELP_WEIRD_OBJ = modules/weird.o CP850_OBJ = modules/CP850.o @@ -670,7 +670,7 @@ SMBD_OBJ_SRV = smbd/files.o smbd/chgpasswd.o smbd/connection.o \ smbd/dosmode.o smbd/filename.o smbd/open.o smbd/close.o \ smbd/blocking.o smbd/sec_ctx.o smbd/srvstr.o \ smbd/vfs.o smbd/statcache.o smbd/seal.o \ - smbd/posix_acls.o lib/sysacls.o $(SERVER_MUTEX_OBJ) \ + smbd/posix_acls.o lib/sysacls.o \ smbd/process.o smbd/service.o smbd/error.o \ printing/printfsp.o lib/sysquotas.o lib/sysquotas_linux.o \ lib/sysquotas_xfs.o lib/sysquotas_4A.o \ @@ -881,7 +881,7 @@ NET_OBJ = $(NET_OBJ1) \ $(KRBCLIENT_OBJ) $(LIB_NONSMBD_OBJ) $(LIBADDNS_OBJ0) \ $(LIBMSRPC_OBJ) $(LIBMSRPC_GEN_OBJ) \ $(LIBADS_OBJ) $(LIBADS_SERVER_OBJ) $(POPT_LIB_OBJ) \ - $(SMBLDAP_OBJ) $(DCUTIL_OBJ) $(SERVER_MUTEX_OBJ) \ + $(SMBLDAP_OBJ) $(DCUTIL_OBJ) \ $(AFS_OBJ) $(AFS_SETTOKEN_OBJ) $(READLINE_OBJ) \ $(LDB_OBJ) $(LIBGPO_OBJ) @BUILD_INIPARSER@ $(DISPLAY_SEC_OBJ) \ $(REG_SMBCONF_OBJ) @LIBNETAPI_STATIC@ $(LIBNET_OBJ) \ @@ -1043,7 +1043,7 @@ WINBINDD_OBJ = \ $(LIBADS_OBJ) $(KRBCLIENT_OBJ) $(POPT_LIB_OBJ) \ $(DCUTIL_OBJ) $(IDMAP_OBJ) $(NSS_INFO_OBJ) \ $(AFS_OBJ) $(AFS_SETTOKEN_OBJ) \ - $(LIBADS_SERVER_OBJ) $(SERVER_MUTEX_OBJ) $(LDB_OBJ) + $(LIBADS_SERVER_OBJ) $(LDB_OBJ) WBINFO_OBJ = nsswitch/wbinfo.o $(LIBSAMBA_OBJ) $(PARAM_OBJ) $(LIB_NONSMBD_OBJ) \ $(POPT_LIB_OBJ) $(AFS_SETTOKEN_OBJ) \ @@ -1109,7 +1109,7 @@ NTLM_AUTH_OBJ1 = utils/ntlm_auth.o utils/ntlm_auth_diagnostics.o NTLM_AUTH_OBJ = ${NTLM_AUTH_OBJ1} $(LIBSAMBA_OBJ) $(POPT_LIB_OBJ) \ libsmb/asn1.o libsmb/spnego.o libsmb/clikrb5.o libads/kerberos.o \ - $(SERVER_MUTEX_OBJ) $(LIBADS_SERVER_OBJ) \ + $(LIBADS_SERVER_OBJ) \ $(PASSDB_OBJ) $(GROUPDB_OBJ) \ $(SMBLDAP_OBJ) $(LIBNMB_OBJ) \ $(LDB_OBJ) $(WBCOMMON_OBJ) @LIBWBCLIENT_STATIC@ \ diff --git a/source/passdb/pdb_tdb.c b/source/passdb/pdb_tdb.c index 80faeb0e984..de49ed2fbca 100644 --- a/source/passdb/pdb_tdb.c +++ b/source/passdb/pdb_tdb.c @@ -142,6 +142,149 @@ static int tdbsam_convert_one(struct db_record *rec, void *priv) return 0; } +/********************************************************************** + Struct and function to backup an old record. + *********************************************************************/ + +struct tdbsam_backup_state { + struct db_context *new_db; + bool success; +}; + +static int backup_copy_fn(struct db_record *orig_rec, void *state) +{ + struct tdbsam_backup_state *bs = (struct tdbsam_backup_state *)state; + struct db_record *new_rec; + NTSTATUS status; + + new_rec = bs->new_db->fetch_locked(bs->new_db, talloc_tos(), orig_rec->key); + if (new_rec == NULL) { + bs->success = false; + return 1; + } + + status = new_rec->store(new_rec, orig_rec->value, TDB_INSERT); + + TALLOC_FREE(new_rec); + + if (!NT_STATUS_IS_OK(status)) { + bs->success = false; + return 1; + } + return 0; +} + +/********************************************************************** + Make a backup of an old passdb and replace the new one with it. We + have to do this as between 3.0.x and 3.2.x the hash function changed + by mistake (used unsigned char * instead of char *). This means the + previous simple update code will fail due to not being able to find + existing records to replace in the tdbsam_convert_one() function. JRA. + *********************************************************************/ + +static bool tdbsam_convert_backup(const char *dbname, struct db_context **pp_db) +{ + TALLOC_CTX *frame = talloc_stackframe(); + const char *tmp_fname = NULL; + struct db_context *tmp_db = NULL; + struct db_context *orig_db = *pp_db; + struct tdbsam_backup_state bs; + int ret; + + tmp_fname = talloc_asprintf(frame, "%s.tmp", dbname); + if (!tmp_fname) { + TALLOC_FREE(frame); + return false; + } + + unlink(tmp_fname); + + /* Remember to open this on the NULL context. We need + * it to stay around after we return from here. */ + + tmp_db = db_open(NULL, tmp_fname, 0, + TDB_DEFAULT, O_CREAT|O_RDWR, 0600); + if (tmp_db == NULL) { + DEBUG(0, ("tdbsam_convert_backup: Failed to create backup TDB passwd " + "[%s]\n", tmp_fname)); + TALLOC_FREE(frame); + return false; + } + + if (orig_db->transaction_start(orig_db) != 0) { + DEBUG(0, ("tdbsam_convert_backup: Could not start transaction (1)\n")); + unlink(tmp_fname); + TALLOC_FREE(tmp_db); + TALLOC_FREE(frame); + return false; + } + if (tmp_db->transaction_start(tmp_db) != 0) { + DEBUG(0, ("tdbsam_convert_backup: Could not start transaction (2)\n")); + orig_db->transaction_cancel(orig_db); + unlink(tmp_fname); + TALLOC_FREE(tmp_db); + TALLOC_FREE(frame); + return false; + } + + bs.new_db = tmp_db; + bs.success = true; + + ret = orig_db->traverse(orig_db, backup_copy_fn, (void *)&bs); + if (ret < 0) { + DEBUG(0, ("tdbsam_convert_backup: traverse failed\n")); + goto cancel; + } + + if (!bs.success) { + DEBUG(0, ("tdbsam_convert_backup: Rewriting records failed\n")); + goto cancel; + } + + if (orig_db->transaction_commit(orig_db) != 0) { + smb_panic("tdbsam_convert_backup: orig commit failed\n"); + } + if (tmp_db->transaction_commit(tmp_db) != 0) { + smb_panic("tdbsam_convert_backup: orig commit failed\n"); + } + + /* This is safe from other users as we know we're + * under a mutex here. */ + + if (rename(tmp_fname, dbname) == -1) { + DEBUG(0, ("tdbsam_convert_backup: rename of %s to %s failed %s\n", + tmp_fname, + dbname, + strerror(errno))); + smb_panic("tdbsam_convert_backup: replace passdb failed\n"); + } + + TALLOC_FREE(frame); + TALLOC_FREE(orig_db); + + DEBUG(1, ("tdbsam_convert_backup: updated %s file.\n", + dbname )); + + /* Replace the global db pointer. */ + *pp_db = tmp_db; + return true; + + cancel: + + if (orig_db->transaction_cancel(orig_db) != 0) { + smb_panic("tdbsam_convert: transaction_cancel failed"); + } + + if (tmp_db->transaction_cancel(tmp_db) != 0) { + smb_panic("tdbsam_convert: transaction_cancel failed"); + } + + unlink(tmp_fname); + TALLOC_FREE(tmp_db); + TALLOC_FREE(frame); + return false; +} + static bool tdbsam_upgrade_next_rid(struct db_context *db) { TDB_CONTEXT *tdb; @@ -173,43 +316,50 @@ static bool tdbsam_upgrade_next_rid(struct db_context *db) return true; } -static bool tdbsam_convert(struct db_context *db, int32 from) +static bool tdbsam_convert(struct db_context **pp_db, const char *name, int32 from) { struct tdbsam_convert_state state; + struct db_context *db = NULL; int ret; + if (!tdbsam_convert_backup(name, pp_db)) { + DEBUG(0, ("tdbsam_convert: Could not backup %s\n", name)); + return false; + } + + db = *pp_db; state.from = from; state.success = true; if (db->transaction_start(db) != 0) { - DEBUG(0, ("Could not start transaction\n")); + DEBUG(0, ("tdbsam_convert: Could not start transaction\n")); return false; } if (!tdbsam_upgrade_next_rid(db)) { - DEBUG(0, ("tdbsam_upgrade_next_rid failed\n")); + DEBUG(0, ("tdbsam_convert: tdbsam_upgrade_next_rid failed\n")); goto cancel; } ret = db->traverse(db, tdbsam_convert_one, &state); if (ret < 0) { - DEBUG(0, ("traverse failed\n")); + DEBUG(0, ("tdbsam_convert: traverse failed\n")); goto cancel; } if (!state.success) { - DEBUG(0, ("Converting records failed\n")); + DEBUG(0, ("tdbsam_convert: Converting records failed\n")); goto cancel; } if (dbwrap_store_int32(db, TDBSAM_VERSION_STRING, TDBSAM_VERSION) != 0) { - DEBUG(0, ("Could not store tdbsam version\n")); + DEBUG(0, ("tdbsam_convert: Could not store tdbsam version\n")); goto cancel; } if (db->transaction_commit(db) != 0) { - DEBUG(0, ("Could not commit transaction\n")); + DEBUG(0, ("tdbsam_convert: Could not commit transaction\n")); return false; } @@ -217,7 +367,7 @@ static bool tdbsam_convert(struct db_context *db, int32 from) cancel: if (db->transaction_cancel(db) != 0) { - smb_panic("transaction_cancel failed"); + smb_panic("tdbsam_convert: transaction_cancel failed"); } return false; @@ -262,17 +412,54 @@ static bool tdbsam_open( const char *name ) } if ( version < TDBSAM_VERSION ) { - DEBUG(1, ("tdbsam_open: Converting version %d database to " - "version %d.\n", version, TDBSAM_VERSION)); + /* + * Ok - we think we're going to have to convert. + * Due to the backup process we now must do to + * upgrade we have to get a mutex and re-check + * the version. Someone else may have upgraded + * whilst we were checking. + */ + + struct named_mutex *mtx = grab_named_mutex(NULL, + "tdbsam_upgrade_mutex", + 600); - if ( !tdbsam_convert(db_sam, version) ) { - DEBUG(0, ("tdbsam_open: Error when trying to convert " - "tdbsam [%s]\n",name)); + if (!mtx) { + DEBUG(0, ("tdbsam_open: failed to grab mutex.\n")); TALLOC_FREE(db_sam); return false; } - DEBUG(3, ("TDBSAM converted successfully.\n")); + /* Re-check the version */ + version = dbwrap_fetch_int32(db_sam, TDBSAM_VERSION_STRING); + if (version == -1) { + version = 0; /* Version not found, assume version 0 */ + } + + /* Compare the version */ + if (version > TDBSAM_VERSION) { + /* Version more recent than the latest known */ + DEBUG(0, ("tdbsam_open: unknown version => %d\n", version)); + TALLOC_FREE(db_sam); + TALLOC_FREE(mtx); + return false; + } + + if ( version < TDBSAM_VERSION ) { + DEBUG(1, ("tdbsam_open: Converting version %d database to " + "version %d.\n", version, TDBSAM_VERSION)); + + if ( !tdbsam_convert(&db_sam, name, version) ) { + DEBUG(0, ("tdbsam_open: Error when trying to convert " + "tdbsam [%s]\n",name)); + TALLOC_FREE(db_sam); + TALLOC_FREE(mtx); + return false; + } + + DEBUG(3, ("TDBSAM converted successfully.\n")); + } + TALLOC_FREE(mtx); } DEBUG(4,("tdbsam_open: successfully opened %s\n", name )); -- 2.11.4.GIT