sVirt AppArmor security driver

* configure.in: look for AppArmor and devel
* src/security/security_apparmor.[ch] src/security/security_driver.c
  src/Makefile.am: add and plug the new driver
* src/security/virt-aa-helper.c: new binary which is used exclusively by
  the AppArmor security driver to manipulate AppArmor.
* po/POTFILES.in: registers the new files
* tests/Makefile.am tests/secaatest.c tests/virt-aa-helper-test:
  tests for virt-aa-helper and the security driver, secaatest.c is
  identical to seclabeltest.c except it initializes the 'apparmor'
  driver instead of 'selinux'

configure.in

@@ -799,6 +799,83 @@ fi
 AM_CONDITIONAL([WITH_SECDRIVER_SELINUX], [test "$with_secdriver_selinux" != "no"])
 
 
+dnl AppArmor
+AC_ARG_WITH([apparmor],
+  [  --with-apparmor        use AppArmor to manage security],
+  [],
+  [with_apparmor=check])
+
+APPARMOR_CFLAGS=
+APPARMOR_LIBS=
+if test "$with_apparmor" != "no"; then
+  old_cflags="$CFLAGS"
+  old_libs="$LIBS"
+  if test "$with_apparmor" = "check"; then
+    AC_CHECK_HEADER([sys/apparmor.h],[],[with_apparmor=no])
+    AC_CHECK_LIB([apparmor], [aa_change_profile],[],[with_apparmor=no])
+    AC_CHECK_LIB([apparmor], [aa_change_hat],[],[with_apparmor=no])
+    if test "$with_apparmor" != "no"; then
+      with_apparmor="yes"
+    fi
+  else
+    fail=0
+    AC_CHECK_HEADER([sys/apparmor.h],[],[fail=1])
+    AC_CHECK_LIB([apparmor], [aa_change_profile],[],[fail=1])
+    AC_CHECK_LIB([apparmor], [aa_change_hat],[],[fail=1])
+    test $fail = 1 &&
+      AC_MSG_ERROR([You must install the AppArmor development package in order to compile libvirt])
+  fi
+  CFLAGS="$old_cflags"
+  LIBS="$old_libs"
+fi
+if test "$with_apparmor" = "yes"; then
+  APPARMOR_LIBS="-lapparmor"
+  AC_DEFINE_UNQUOTED([HAVE_APPARMOR], 1, [whether AppArmor is available for security])
+  AC_DEFINE_UNQUOTED([APPARMOR_DIR], "/etc/apparmor.d", [path to apparmor directory])
+  AC_DEFINE_UNQUOTED([APPARMOR_PROFILES_PATH], "/sys/kernel/security/apparmor/profiles", [path to kernel profiles])
+fi
+AM_CONDITIONAL([HAVE_APPARMOR], [test "$with_apparmor" != "no"])
+AC_SUBST([APPARMOR_CFLAGS])
+AC_SUBST([APPARMOR_LIBS])
+
+
+AC_ARG_WITH([secdriver-apparmor],
+  [  --with-secdriver-apparmor         use AppArmor security driver],
+  [],
+  [with_secdriver_apparmor=check])
+
+if test "$with_apparmor" != "yes" ; then
+  if test "$with_secdriver_apparmor" = "check" ; then
+    with_secdriver_apparmor=no
+  else
+    AC_MSG_ERROR([You must install the AppArmor development package in order to compile libvirt])
+  fi
+else
+  old_cflags="$CFLAGS"
+  old_libs="$LIBS"
+  CFLAGS="$CFLAGS $APPARMOR_CFLAGS"
+  LIBS="$CFLAGS $APPARMOR_LIBS"
+
+  fail=0
+  AC_CHECK_FUNC([change_hat], [], [fail=1])
+  AC_CHECK_FUNC([aa_change_profile], [], [fail=1])
+  CFLAGS="$old_cflags"
+  LIBS="$old_libs"
+
+  if test "$fail" = "1" ; then
+    if test "$with_secdriver_apparmor" = "check" ; then
+      with_secdriver_apparmor=no
+    else
+      AC_MSG_ERROR([You must install the AppArmor development package in order to compile libvirt])
+    fi
+  else
+    with_secdriver_apparmor=yes
+    AC_DEFINE_UNQUOTED([WITH_SECDRIVER_APPARMOR], 1, [whether AppArmor security driver is available])
+  fi
+fi
+AM_CONDITIONAL([WITH_SECDRIVER_APPARMOR], [test "$with_secdriver_apparmor" != "no"])
+
+
 
 dnl NUMA lib
 AC_ARG_WITH([numactl],
@@ -1745,6 +1822,7 @@ AC_MSG_NOTICE([])
 AC_MSG_NOTICE([Security Drivers])
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([ SELinux: $with_secdriver_selinux])
+AC_MSG_NOTICE([ AppArmor: $with_secdriver_apparmor])
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([Driver Loadable Modules])
 AC_MSG_NOTICE([])
@@ -1792,6 +1870,11 @@ AC_MSG_NOTICE([ selinux: $SELINUX_CFLAGS $SELINUX_LIBS])
 else
 AC_MSG_NOTICE([ selinux: no])
 fi
+if test "$with_apparmor" = "yes" ; then
+AC_MSG_NOTICE([ apparmor: $APPARMOR_CFLAGS $APPARMOR_LIBS])
+else
+AC_MSG_NOTICE([ apparmor: no])
+fi
 if test "$with_numactl" = "yes" ; then
 AC_MSG_NOTICE([ numactl: $NUMACTL_CFLAGS $NUMACTL_LIBS])
 else

po/POTFILES.in

@@ -30,7 +30,9 @@ src/qemu/qemu_monitor_text.c
 src/remote/remote_driver.c
 src/secret/secret_driver.c
 src/security/security_driver.c
+src/security/security_apparmor.c
 src/security/security_selinux.c
+src/security/virt-aa-helper.c
 src/storage/storage_backend.c
 src/storage/storage_backend_disk.c
 src/storage/storage_backend_fs.c

src/Makefile.am

@@ -153,6 +153,9 @@ LXC_CONTROLLER_SOURCES =					\
 		lxc/lxc_controller.c				\
 		lxc/veth.c lxc/veth.h
 
+SECURITY_DRIVER_APPARMOR_HELPER_SOURCES =			\
+		security/virt-aa-helper.c
+
 PHYP_DRIVER_SOURCES =						\
 		phyp/phyp_driver.c phyp/phyp_driver.h
 
@@ -238,6 +241,9 @@ SECURITY_DRIVER_SOURCES =					\
 SECURITY_DRIVER_SELINUX_SOURCES =				\
 		security/security_selinux.h security/security_selinux.c
 
+SECURITY_DRIVER_APPARMOR_SOURCES =				\
+		security/security_apparmor.h security/security_apparmor.c
+
 
 NODE_DEVICE_DRIVER_SOURCES =					\
 		node_device/node_device_driver.c node_device/node_device_driver.h
@@ -641,9 +647,15 @@ noinst_LTLIBRARIES += libvirt_driver_security.la
 libvirt_la_LIBADD += libvirt_driver_security.la
 libvirt_driver_security_la_CFLAGS = \
 		-I@top_srcdir@/src/conf
+libvirt_driver_security_la_LDFLAGS =
 if WITH_SECDRIVER_SELINUX
 libvirt_driver_security_la_SOURCES += $(SECURITY_DRIVER_SELINUX_SOURCES)
 endif
+if WITH_SECDRIVER_APPARMOR
+libvirt_driver_security_la_SOURCES += $(SECURITY_DRIVER_APPARMOR_SOURCES)
+libvirt_driver_security_la_CFLAGS += $(APPARMOR_CFLAGS)
+libvirt_driver_security_la_LDFLAGS += $(APPARMOR_LIBS)
+endif
 
 # Add all conditional sources just in case...
 EXTRA_DIST +=							\
@@ -671,6 +683,7 @@ EXTRA_DIST +=							\
 		$(NODE_DEVICE_DRIVER_HAL_SOURCES)		\
 		$(NODE_DEVICE_DRIVER_DEVKIT_SOURCES)		\
 		$(SECURITY_DRIVER_SELINUX_SOURCES)		\
+		$(SECURITY_DRIVER_APPARMOR_SOURCES)		\
 		$(SECRET_DRIVER_SOURCES)			\
 		$(VBOX_DRIVER_EXTRA_DIST)
 
@@ -795,6 +808,26 @@ endif
 endif
 EXTRA_DIST += $(LXC_CONTROLLER_SOURCES)
 
+if WITH_SECDRIVER_APPARMOR
+if WITH_LIBVIRTD
+libexec_PROGRAMS += virt-aa-helper
+
+virt_aa_helper_SOURCES = $(SECURITY_DRIVER_APPARMOR_HELPER_SOURCES)
+
+virt_aa_helper_LDFLAGS = $(WARN_CFLAGS)
+virt_aa_helper_LDADD =						\
+		$(WARN_CFLAGS)					\
+		$(LIBXML_LIBS)					\
+		@top_srcdir@/gnulib/lib/libgnu.la		\
+		@top_srcdir@/src/libvirt_conf.la		\
+		@top_srcdir@/src/libvirt_util.la
+virt_aa_helper_CFLAGS =						\
+		-I@top_srcdir@/src/conf				\
+		-I@top_srcdir@/src/security
+endif
+endif
+EXTRA_DIST += $(SECURITY_DRIVER_APPARMOR_HELPER_SOURCES)
+
 install-data-local:
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/cache/libvirt"
 	$(MKDIR_P) "$(DESTDIR)$(localstatedir)/lib/libvirt/images"

src/security/security_apparmor.c

+
+/*
+ * AppArmor security driver for libvirt
+ * Copyright (C) 2009 Canonical Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Author:
+ *   Jamie Strandboge <jamie@canonical.com>
+ *   Based on security_selinux.c by James Morris <jmorris@namei.org>
+ *
+ * AppArmor security driver.
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/apparmor.h>
+#include <errno.h>
+#include <unistd.h>
+#include <wait.h>
+#include <stdbool.h>
+
+#include "internal.h"
+
+#include "security_driver.h"
+#include "security_apparmor.h"
+#include "util.h"
+#include "memory.h"
+#include "virterror_internal.h"
+#include "datatypes.h"
+#include "uuid.h"
+
+#define VIR_FROM_THIS VIR_FROM_SECURITY
+#define SECURITY_APPARMOR_VOID_DOI      "0"
+#define SECURITY_APPARMOR_NAME          "apparmor"
+#define VIRT_AA_HELPER BINDIR "/virt-aa-helper"
+
+/*
+ * profile_status returns '-1' on error, '0' if loaded
+ *
+ * If check_enforcing is set to '1', then returns '-1' on error, '0' if
+ * loaded in complain mode, and '1' if loaded in enforcing mode.
+ */
+static int
+profile_status(const char *str, const int check_enforcing)
+{
+    char *content = NULL;
+    char *tmp = NULL;
+    char *etmp = NULL;
+    int rc = -1;
+
+    /* create string that is '<str> \0' for accurate matching */
+    if (virAsprintf(&tmp, "%s ", str) == -1)
+        return rc;
+
+    if (check_enforcing != 0) {
+        /* create string that is '<str> (enforce)\0' for accurate matching */
+        if (virAsprintf(&etmp, "%s (enforce)", str) == -1) {
+            VIR_FREE(tmp);
+            return rc;
+        }
+    }
+
+    if (virFileReadAll(APPARMOR_PROFILES_PATH, MAX_FILE_LEN, &content) < 0) {
+        virReportSystemError(NULL, errno,
+                             _("Failed to read AppArmor profiles list "
+                             "\'%s\'"), APPARMOR_PROFILES_PATH);
+        if (check_enforcing != 0)
+            VIR_FREE(etmp);
+        goto clean;
+    }
+
+    if (strstr(content, tmp) != NULL)
+        rc = 0;
+    if (check_enforcing != 0) {
+        if (rc == 0 && strstr(content, etmp) != NULL)
+            rc = 1;                 /* return '1' if loaded and enforcing */
+        VIR_FREE(etmp);
+    }
+
+    VIR_FREE(content);
+  clean:
+    VIR_FREE(tmp);
+
+    return rc;
+}
+
+static int
+profile_loaded(const char *str)
+{
+    return profile_status(str, 0);
+}
+
+/*
+ * profile_status_file returns '-1' on error, '0' if file on disk is in
+ * complain mode and '1' if file on disk is in enforcing mode
+ */
+static int
+profile_status_file(const char *str)
+{
+    char profile[PATH_MAX];
+    char *content = NULL;
+    char *tmp = NULL;
+    int rc = -1;
+    int len;
+
+    if (snprintf(profile, PATH_MAX, "%s/%s", APPARMOR_DIR "/libvirt", str)
+       > PATH_MAX - 1) {
+        virSecurityReportError(NULL, VIR_ERR_ERROR,
+                               "%s", _("profile name exceeds maximum length"));
+    }
+
+    if (!virFileExists(profile)) {
+        return rc;
+    }
+
+    if ((len = virFileReadAll(profile, MAX_FILE_LEN, &content)) < 0) {
+        virReportSystemError(NULL, errno,
+                             _("Failed to read \'%s\'"), profile);
+        return rc;
+    }
+
+    /* create string that is ' <str> flags=(complain)\0' */
+    if (virAsprintf(&tmp, " %s flags=(complain)", str) == -1) {
+        virReportOOMError(NULL);
+        goto clean;
+    }
+
+    if (strstr(content, tmp) != NULL)
+        rc = 0;
+    else
+        rc = 1;
+
+    VIR_FREE(tmp);
+  clean:
+    VIR_FREE(content);
+
+    return rc;
+}
+
+/*
+ * load (add) a profile. Will create one if necessary
+ */
+static int
+load_profile(virConnectPtr conn, const char *profile, virDomainObjPtr vm,
+             virDomainDiskDefPtr disk)
+{
+    int rc = -1, status, ret;
+    bool create = true;
+    char *xml = NULL;
+    int pipefd[2];
+    pid_t child;
+
+    if (pipe(pipefd) < -1) {
+        virReportSystemError(conn, errno, "%s", _("unable to create pipe"));
+        return rc;
+    }
+
+    xml = virDomainDefFormat(conn, vm->def, VIR_DOMAIN_XML_SECURE);
+    if (!xml)
+        goto failed;
+
+    if (profile_status_file(profile) >= 0)
+        create = false;
+
+    if (create) {
+        const char *const argv[] = {
+            VIRT_AA_HELPER, "-c", "-u", profile, NULL
+        };
+        ret = virExec(conn, argv, NULL, NULL, &child,
+                      pipefd[0], NULL, NULL, VIR_EXEC_CLEAR_CAPS);
+    } else if (disk && disk->src) {
+        const char *const argv[] = {
+            VIRT_AA_HELPER, "-r", "-u", profile, "-f", disk->src, NULL
+        };
+        ret = virExec(conn, argv, NULL, NULL, &child,
+                      pipefd[0], NULL, NULL, VIR_EXEC_CLEAR_CAPS);
+    } else {
+        const char *const argv[] = {
+            VIRT_AA_HELPER, "-r", "-u", profile, NULL
+        };
+        ret = virExec(conn, argv, NULL, NULL, &child,
+                      pipefd[0], NULL, NULL, VIR_EXEC_CLEAR_CAPS);
+    }
+    if (ret < 0)
+        goto clean;
+
+    /* parent continues here */
+    if (safewrite(pipefd[1], xml, strlen(xml)) < 0) {
+        virReportSystemError(conn, errno, "%s", _("unable to write to pipe"));
+        goto clean;
+    }
+    close(pipefd[1]);
+    rc = 0;
+
+  rewait:
+    if (waitpid(child, &status, 0) != child) {
+        if (errno == EINTR)
+            goto rewait;
+
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               _("Unexpected exit status from virt-aa-helper "
+                               "%d pid %lu"),
+                               WEXITSTATUS(status), (unsigned long)child);
+        rc = -1;
+    }
+
+  clean:
+    VIR_FREE(xml);
+
+  failed:
+    if (pipefd[0] > 0)
+        close(pipefd[0]);
+    if (pipefd[1] > 0)
+        close(pipefd[1]);
+
+    return rc;
+}
+
+static int
+remove_profile(const char *profile)
+{
+    int rc = -1;
+    const char * const argv[] = {
+        VIRT_AA_HELPER, "-R", "-u", profile, NULL
+    };
+
+    if (virRun(NULL, argv, NULL) == 0)
+        rc = 0;
+
+    return rc;
+}
+
+static char *
+get_profile_name(virConnectPtr conn, virDomainObjPtr vm)
+{
+    char uuidstr[VIR_UUID_STRING_BUFLEN];
+    char *name = NULL;
+
+    virUUIDFormat(vm->def->uuid, uuidstr);
+    if (virAsprintf(&name, "%s%s", AA_PREFIX, uuidstr) < 0) {
+        virReportOOMError(conn);
+        return NULL;
+    }
+
+    return name;
+}
+
+/* returns -1 on error or profile for libvirtd is unconfined, 0 if complain
+ * mode and 1 if enforcing. This is required because at present you cannot
+ * aa_change_profile() from a process that is unconfined.
+ */
+static int
+use_apparmor(void)
+{
+    char libvirt_daemon[PATH_MAX];
+    int rc = -1;
+    ssize_t len = 0;
+
+    if ((len = readlink("/proc/self/exe", libvirt_daemon,
+                        PATH_MAX - 1)) < 0) {
+        virSecurityReportError(NULL, VIR_ERR_ERROR,
+                               "%s", _("could not find libvirtd"));
+        return rc;
+    }
+    libvirt_daemon[len] = '\0';
+
+    if (access(APPARMOR_PROFILES_PATH, R_OK) != 0)
+        return rc;
+
+    return profile_status(libvirt_daemon, 1);
+}
+
+/* Called on libvirtd startup to see if AppArmor is available */
+static int
+AppArmorSecurityDriverProbe(void)
+{
+    char template[PATH_MAX];
+
+    if (use_apparmor() < 0)
+        return SECURITY_DRIVER_DISABLE;
+
+    /* see if template file exists */
+    if (snprintf(template, PATH_MAX, "%s/TEMPLATE",
+                 APPARMOR_DIR "/libvirt") > PATH_MAX - 1) {
+        virSecurityReportError(NULL, VIR_ERR_ERROR,
+                               "%s", _("template too large"));
+        return SECURITY_DRIVER_DISABLE;
+    }
+
+    if (!virFileExists(template)) {
+        virSecurityReportError(NULL, VIR_ERR_ERROR,
+                               _("template \'%s\' does not exist"), template);
+        return SECURITY_DRIVER_DISABLE;
+    }
+
+    return SECURITY_DRIVER_ENABLE;
+}
+
+/* Security driver initialization. DOI is for 'Domain of Interpretation' and is
+ * currently not used.
+ */
+static int
+AppArmorSecurityDriverOpen(virConnectPtr conn, virSecurityDriverPtr drv)
+{
+    virSecurityDriverSetDOI(conn, drv, SECURITY_APPARMOR_VOID_DOI);
+    return 0;
+}
+
+/* Currently called in qemudStartVMDaemon to setup a 'label'. We look for and
+ * use a profile based on the UUID, otherwise create one based on a template.
+ * Keep in mind that this is called on 'start' with RestoreSecurityLabel being
+ * called on shutdown.
+*/
+static int
+AppArmorGenSecurityLabel(virConnectPtr conn, virDomainObjPtr vm)
+{
+    int rc = -1;
+    char *profile_name = NULL;
+
+    if ((vm->def->seclabel.label) ||
+        (vm->def->seclabel.model) || (vm->def->seclabel.imagelabel)) {
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               "%s",
+                               _("security label already defined for VM"));
+        return rc;
+    }
+
+    if ((profile_name = get_profile_name(conn, vm)) == NULL)
+        return rc;
+
+    /* if the profile is not already loaded, then load one */
+    if (profile_loaded(profile_name) < 0) {
+        if (load_profile(conn, profile_name, vm, NULL) < 0) {
+            virSecurityReportError(conn, VIR_ERR_ERROR,
+                                   _("cannot generate AppArmor profile "
+                                   "\'%s\'"), profile_name);
+            goto clean;
+        }
+    }
+
+    vm->def->seclabel.label = strndup(profile_name, strlen(profile_name));
+    if (!vm->def->seclabel.label) {
+        virReportOOMError(NULL);
+        goto clean;
+    }
+
+    /* set imagelabel the same as label (but we won't use it) */
+    vm->def->seclabel.imagelabel = strndup(profile_name,
+                                           strlen(profile_name));
+    if (!vm->def->seclabel.imagelabel) {
+        virReportOOMError(NULL);
+        goto err;
+    }
+
+    vm->def->seclabel.model = strdup(SECURITY_APPARMOR_NAME);
+    if (!vm->def->seclabel.model) {
+        virReportOOMError(conn);
+        goto err;
+    }
+
+    rc = 0;
+    goto clean;
+
+  err:
+    remove_profile(profile_name);
+    VIR_FREE(vm->def->seclabel.label);
+    VIR_FREE(vm->def->seclabel.imagelabel);
+    VIR_FREE(vm->def->seclabel.model);
+
+  clean:
+    VIR_FREE(profile_name);
+
+    return rc;
+}
+
+/* Seen with 'virsh dominfo <vm>'. This function only called if the VM is
+ * running.
+ */
+static int
+AppArmorGetSecurityLabel(virConnectPtr conn,
+                         virDomainObjPtr vm, virSecurityLabelPtr sec)
+{
+    int rc = -1;
+    char *profile_name = NULL;
+
+    if ((profile_name = get_profile_name(conn, vm)) == NULL)
+        return rc;
+
+    if (virStrcpy(sec->label, profile_name,
+        VIR_SECURITY_LABEL_BUFLEN) == NULL) {
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               "%s", _("error copying profile name"));
+        goto clean;
+    }
+
+    if ((sec->enforcing = profile_status(profile_name, 1)) < 0) {
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               "%s", _("error calling profile_status()"));
+        goto clean;
+    }
+    rc = 0;
+
+  clean:
+    VIR_FREE(profile_name);
+
+    return rc;
+}
+
+/* Called on VM shutdown and destroy. See AppArmorGenSecurityLabel (above) for
+ * more details. Currently called via qemudShutdownVMDaemon.
+ */
+static int
+AppArmorRestoreSecurityLabel(virConnectPtr conn, virDomainObjPtr vm)
+{
+    const virSecurityLabelDefPtr secdef = &vm->def->seclabel;
+    int rc = 0;
+
+    if (secdef->imagelabel) {
+        if ((rc = remove_profile(secdef->label)) != 0) {
+            virSecurityReportError(conn, VIR_ERR_ERROR,
+                                   _("could not remove profile for \'%s\'"),
+                                   secdef->label);
+        }
+        VIR_FREE(secdef->model);
+        VIR_FREE(secdef->label);
+        VIR_FREE(secdef->imagelabel);
+    }
+    return rc;
+}
+
+/* Called via virExecWithHook. Output goes to
+ * LOCAL_STATE_DIR/log/libvirt/qemu/<vm name>.log
+ */
+static int
+AppArmorSetSecurityLabel(virConnectPtr conn,
+                         virSecurityDriverPtr drv, virDomainObjPtr vm)
+{
+    const virSecurityLabelDefPtr secdef = &vm->def->seclabel;
+    int rc = -1;
+    char *profile_name = NULL;
+
+    if ((profile_name = get_profile_name(conn, vm)) == NULL)
+        return rc;
+
+    if (STRNEQ(drv->name, secdef->model)) {
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               _("security label driver mismatch: "
+                               "\'%s\' model configured for domain, but "
+                               "hypervisor driver is \'%s\'."),
+                               secdef->model, drv->name);
+        if (use_apparmor() > 0)
+            goto clean;
+    }
+
+    if (aa_change_profile(profile_name) < 0) {
+        virSecurityReportError(conn, VIR_ERR_ERROR,
+                               _("error calling aa_change_profile()"));
+        goto clean;
+    }
+    rc = 0;
+
+  clean:
+    VIR_FREE(profile_name);
+
+    return rc;
+}
+
+
+/* Called when hotplugging */
+static int
+AppArmorRestoreSecurityImageLabel(virConnectPtr conn,
+                                  virDomainObjPtr vm,
+                                  virDomainDiskDefPtr disk ATTRIBUTE_UNUSED)
+{
+    const virSecurityLabelDefPtr secdef = &vm->def->seclabel;
+    int rc = -1;
+    char *profile_name = NULL;
+
+    if (secdef->imagelabel) {
+        if ((profile_name = get_profile_name(conn, vm)) == NULL)
+            return rc;
+
+        /* Update the profile only if it is loaded */
+        if (profile_loaded(secdef->imagelabel) >= 0) {
+            if (load_profile(conn, secdef->imagelabel, vm, NULL) < 0) {
+                virSecurityReportError(conn, VIR_ERR_ERROR,
+                                       _("cannot update AppArmor profile "
+                                       "\'%s\'"),
+                                       secdef->imagelabel);
+                goto clean;
+            }
+        }
+    }
+    rc = 0;
+  clean:
+    VIR_FREE(profile_name);
+
+    return rc;
+}
+
+/* Called when hotplugging */
+static int
+AppArmorSetSecurityImageLabel(virConnectPtr conn,
+                              virDomainObjPtr vm, virDomainDiskDefPtr disk)
+{
+    const virSecurityLabelDefPtr secdef = &vm->def->seclabel;
+    int rc = -1;
+    char *profile_name;
+
+    if (!disk->src)
+        return 0;
+
+    if (secdef->imagelabel) {
+        /* if the device doesn't exist, error out */
+        if (!virFileExists(disk->src)) {
+            virSecurityReportError(conn, VIR_ERR_ERROR,
+                                   _("\'%s\' does not exist"), disk->src);
+            return rc;
+        }
+
+        if ((profile_name = get_profile_name(conn, vm)) == NULL)
+            return rc;
+
+        /* update the profile only if it is loaded */
+        if (profile_loaded(secdef->imagelabel) >= 0) {
+            if (load_profile(conn, secdef->imagelabel, vm, disk) < 0) {
+                virSecurityReportError(conn, VIR_ERR_ERROR,
+                                     _("cannot update AppArmor profile "
+                                     "\'%s\'"),
+                                     secdef->imagelabel);
+                goto clean;
+            }
+        }
+    }
+    rc = 0;
+
+  clean:
+    VIR_FREE(profile_name);
+
+    return rc;
+}
+
+static int
+AppArmorSecurityVerify(virConnectPtr conn, virDomainDefPtr def)
+{
+    const virSecurityLabelDefPtr secdef = &def->seclabel;
+
+    if (secdef->type == VIR_DOMAIN_SECLABEL_STATIC) {
+        if (use_apparmor() < 0 || profile_status(secdef->label, 0) < 0) {
+            virSecurityReportError(conn, VIR_ERR_XML_ERROR,
+                                   _("Invalid security label \'%s\'"),
+                                   secdef->label);
+            return -1;
+        }
+    }
+    return 0;
+}
+
+static int
+AppArmorReserveSecurityLabel(virConnectPtr conn ATTRIBUTE_UNUSED,
+                            virDomainObjPtr vm ATTRIBUTE_UNUSED)
+{
+    /* NOOP. Nothing to reserve with AppArmor */
+    return 0;
+}
+
+static int
+AppArmorSetSecurityHostdevLabel(virConnectPtr conn ATTRIBUTE_UNUSED,
+                                virDomainObjPtr vm ATTRIBUTE_UNUSED,
+                                virDomainHostdevDefPtr dev ATTRIBUTE_UNUSED)
+
+{
+    /* TODO: call load_profile with an update vm->def */
+    return 0;
+}
+
+static int
+AppArmorRestoreSecurityHostdevLabel(virConnectPtr conn ATTRIBUTE_UNUSED,
+                                    virDomainHostdevDefPtr dev ATTRIBUTE_UNUSED)
+
+{
+    /* TODO: call load_profile (needs virDomainObjPtr vm) */
+    return 0;
+}
+
+virSecurityDriver virAppArmorSecurityDriver = {
+    .name = SECURITY_APPARMOR_NAME,
+    .probe = AppArmorSecurityDriverProbe,
+    .open = AppArmorSecurityDriverOpen,
+    .domainSecurityVerify = AppArmorSecurityVerify,
+    .domainSetSecurityImageLabel = AppArmorSetSecurityImageLabel,
+    .domainRestoreSecurityImageLabel = AppArmorRestoreSecurityImageLabel,
+    .domainGenSecurityLabel = AppArmorGenSecurityLabel,
+    .domainReserveSecurityLabel = AppArmorReserveSecurityLabel,
+    .domainGetSecurityLabel = AppArmorGetSecurityLabel,
+    .domainRestoreSecurityLabel = AppArmorRestoreSecurityLabel,
+    .domainSetSecurityLabel = AppArmorSetSecurityLabel,
+    .domainSetSecurityHostdevLabel = AppArmorSetSecurityHostdevLabel,
+    .domainRestoreSecurityHostdevLabel = AppArmorRestoreSecurityHostdevLabel,
+};

src/security/security_apparmor.h

+
+/*
+ * Copyright (C) 2009 Canonical Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Author:
+ *   Jamie Strandboge <jamie@canonical.com>
+ *
+ */
+#ifndef __VIR_SECURITY_APPARMOR_H__
+#define __VIR_SECURITY_APPARMOR_H__
+
+extern virSecurityDriver virAppArmorSecurityDriver;
+
+#define AA_PREFIX  "libvirt-"
+#define PROFILE_NAME_SIZE  8 + VIR_UUID_STRING_BUFLEN /* AA_PREFIX + uuid */
+#define MAX_FILE_LEN       (1024*1024*10)  /* 10MB limit for sanity check */
+
+#endif /* __VIR_SECURITY_APPARMOR_H__ */

src/security/security_driver.c

@@ -20,9 +20,16 @@
 #include "security_selinux.h"
 #endif
 
+#ifdef WITH_SECDRIVER_APPARMOR
+#include "security_apparmor.h"
+#endif
+
 static virSecurityDriverPtr security_drivers[] = {
 #ifdef WITH_SECDRIVER_SELINUX
     &virSELinuxSecurityDriver,
+#endif
+#ifdef WITH_SECDRIVER_APPARMOR
+    &virAppArmorSecurityDriver,
 #endif
     NULL
 };

tests/Makefile.am

@@ -16,6 +16,7 @@ INCLUDES = \
 	$(GNUTLS_CFLAGS) \
 	$(SASL_CFLAGS) \
 	$(SELINUX_CFLAGS) \
+	$(APPARMOR_CFLAGS) \
         -DGETTEXT_PACKAGE=\"$(PACKAGE)\" \
          $(COVERAGE_CFLAGS) \
          $(WARN_CFLAGS)
@@ -31,6 +32,7 @@ LDADDS = \
         $(GNUTLS_LIBS) \
         $(SASL_LIBS) \
         $(SELINUX_LIBS) \
+        $(APPARMOR_LIBS) \
         $(WARN_CFLAGS) \
 	../src/libvirt_test.la \
 	../gnulib/lib/libgnu.la \
@@ -84,6 +86,10 @@ if WITH_SECDRIVER_SELINUX
 noinst_PROGRAMS += seclabeltest
 endif
 
+if WITH_SECDRIVER_APPARMOR
+noinst_PROGRAMS += secaatest
+endif
+
 if WITH_CIL
 noinst_PROGRAMS += object-locking
 endif
@@ -119,6 +125,9 @@ test_scripts +=				\
 	virsh-synopsis
 endif
 
+if WITH_SECDRIVER_APPARMOR
+test_scripts += virt-aa-helper-test
+endif
 EXTRA_DIST += $(test_scripts)
 
 TESTS = virshtest \
@@ -149,6 +158,10 @@ if WITH_SECDRIVER_SELINUX
 TESTS += seclabeltest
 endif
 
+if WITH_SECDRIVER_APPARMOR
+TESTS += secaatest
+endif
+
 if WITH_LIBVIRTD
 noinst_PROGRAMS += eventtest
 TESTS += eventtest
@@ -285,6 +298,14 @@ else
 EXTRA_DIST += seclabeltest.c
 endif
 
+if WITH_SECDRIVER_APPARMOR
+secaatest_SOURCES = \
+	secaatest.c
+secaatest_LDADD = ../src/libvirt_driver_security.la $(LDADDS)
+else
+EXTRA_DIST += secaatest.c
+endif
+
 qparamtest_SOURCES = \
 	qparamtest.c testutils.h testutils.c
 qparamtest_LDADD = $(LDADDS)

tests/secaatest.c

+#include <config.h>
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include "security/security_driver.h"
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
+{
+    int ret;
+
+    const char *doi, *model;
+    virSecurityDriverPtr security_drv;
+
+    ret = virSecurityDriverStartup (&security_drv, "apparmor");
+    if (ret == -1)
+    {
+        fprintf (stderr, "Failed to start security driver");
+        exit (-1);
+    }
+    /* No security driver wanted to be enabled: just return */
+    if (ret == -2)
+        return 0;
+
+    model = virSecurityDriverGetModel (security_drv);
+    if (!model)
+    {
+        fprintf (stderr, "Failed to copy secModel model: %s",
+                 strerror (errno));
+        exit (-1);
+    }
+
+    doi = virSecurityDriverGetDOI (security_drv);
+    if (!doi)
+    {
+        fprintf (stderr, "Failed to copy secModel DOI: %s",
+                 strerror (errno));
+        exit (-1);
+    }
+
+    return 0;
+}

tests/virt-aa-helper-test

+#!/bin/sh
+set -e
+
+test_hostdev="no"
+if [ "$1" = "test_hostdev" ]; then
+    test_hostdev="yes"
+    shift
+fi
+
+output="/dev/null"
+use_valgrind=""
+ld_library_path="../src/.libs/"
+if [ ! -z "$1" ] && [ "$1" = "-d" ]; then
+    output="/dev/stdout"
+    shift
+fi
+
+exe="../src/virt-aa-helper"
+if [ ! -z "$1" ]; then
+    if [ "$1" = "-v" ]; then
+        use_valgrind="yes"
+        shift
+    fi
+    if [ -n "$1" ]; then
+        exe="$1"
+        shift
+    fi
+fi
+
+if [ ! -x "$exe" ]; then
+    echo "Could not find '$exe'"
+    exit 1
+fi
+
+echo "testing `basename $exe`" >$output
+if [ "$use_valgrind" = "yes" ]; then
+    exe="valgrind --error-exitcode=2 --track-origins=yes $exe"
+fi
+
+extra_args="--dryrun"
+errors=0
+
+tmpdir=`mktemp -d`
+trap "rm -rf $tmpdir" EXIT HUP INT QUIT TERM
+
+template_xml="$tmpdir/template.xml"
+test_xml="$tmpdir/test.xml"
+
+uuid="00000000-0000-0000-0000-0123456789ab"
+disk1="$tmpdir/1.img"
+disk2="$tmpdir/2.img"
+relative_disk1="$tmpdir/./../`basename $tmpdir`//./1.img"
+nonexistent="$tmpdir/nonexistant.img"
+bad_disk="/etc/passwd"
+valid_uuid="libvirt-$uuid"
+nonexistent_uuid="libvirt-00000000-0000-0000-0000-000000000001"
+
+cat > "$template_xml" <<EOM
+<domain type='kvm'>
+  <name>virt-aa-helper-test</name>
+  <uuid>###UUID###</uuid>
+  <memory>524288</memory>
+  <currentMemory>524288</currentMemory>
+  <vcpu>1</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <features>
+    <acpi/>
+  </features>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/kvm</emulator>
+    <disk type='file' device='disk'>
+      <source file='###DISK###'/>
+      <target dev='hda' bus='ide'/>
+    </disk>
+    <interface type='network'>
+      <mac address='52:54:00:50:4b:26'/>
+      <source network='default'/>
+      <model type='virtio'/>
+    </interface>
+    <input type='tablet' bus='usb'/>
+    <input type='mouse' bus='ps2'/>
+    <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1'/>
+    <video>
+      <model type='cirrus' vram='9216' heads='1'/>
+    </video>
+  </devices>
+</domain>
+EOM
+
+touch "$disk1" "$disk2"
+
+testme() {
+    expected="$1"
+    outstr="$2"
+    args="$3"
+    input=""
+
+    if [ -n "$4" ]; then
+        input="$4"
+        if [ ! -e "$input" ]; then
+            echo "FAIL: could not find $input" >$output
+            echo "FAIL: could not find $input"
+            echo " '$extra_args $args': "
+            errors=$(($errors + 1))
+        fi
+    fi
+
+    echo -n "  $outstr: " >$output
+    echo -n " '$extra_args $args" >$output
+    if [ -n "$input" ]; then
+        echo -n " < $input" >$output
+    fi
+    echo "': " >$output
+    set +e
+    if [ -n "$input" ]; then
+        LD_LIBRARY_PATH="$ld_library_path" $exe $extra_args $args < $input >$output 2>&1
+    else
+        LD_LIBRARY_PATH="$ld_library_path" $exe $extra_args $args >$output 2>&1
+    fi
+    rc="$?"
+    set -e
+    if [ "$rc" = "$expected" ]; then
+        echo "pass" >$output
+    else
+        echo "FAIL: exited with '$rc'" >$output
+        echo "FAIL: exited with '$rc'"
+        echo -n "  $outstr: "
+        echo " '$extra_args $args': "
+        errors=$(($errors + 1))
+        #exit $rc
+    fi
+}
+
+# Expected failures
+echo "Expected failures:" >$output
+testme "1" "invalid arg" "-z"
+testme "1" "invalid case" "-A"
+testme "1" "not enough args" "-c"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" > "$test_xml"
+testme "1" "no -u with -c" "-c" "$test_xml"
+testme "1" "bad uuid (bad digit)" "-c -u libvirt-00000000-0000-0000-0000-00000000000g" "$test_xml"
+testme "1" "bad uuid (too long)" "-c -u ${valid_uuid}abcdef" "$test_xml"
+testme "1" "bad uuid (too short)" "-c -u libvirt-00000000-0000-0000-0000-0123456789a" "$test_xml"
+testme "1" "non-matching uuid" "-c -u libvirt-00000000-0000-0000-0000-00000000000a" "$test_xml"
+testme "1" "missing uuid" "-c -u" "$test_xml"
+testme "1" "no -u with -R" "-R"
+testme "1" "non-existent uuid" "-R -u $nonexistent_uuid"
+testme "1" "no -u with -r" "-r"
+testme "1" "old '-n' option" "-c -n foo -u $valid_uuid" "$test_xml"
+testme "1" "invalid bits" "-c -b 15 -u $valid_uuid" "$test_xml"
+testme "1" "invalid bits2" "-c -b a -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$bad_disk,g" > "$test_xml"
+testme "1" "bad disk" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$bad_disk,g" | sed "s,</devices>,<disk type='file' device='disk'><source file='$disk2'<target dev='hda' bus='ide'/></disk></devices>,g" > "$test_xml"
+testme "1" "bad disk2" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<devices>,g" > "$test_xml"
+testme "1" "malformed xml" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,/boot/initrd,g" > "$test_xml"
+testme "1" "disk in /boot" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,/boot/initrd,g" > "$test_xml"
+testme "1" "-r with invalid -f" "-r -u $valid_uuid -f $bad_disk" "$test_xml"
+
+
+echo "Expected pass:" >$output
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" > "$test_xml"
+testme "0" "create" "-c -u $valid_uuid" "$test_xml"
+testme "0" "create with bits (32)" "-c -b 32 -u $valid_uuid" "$test_xml"
+testme "0" "create with bits (64)" "-c -b 64 -u $valid_uuid" "$test_xml"
+testme "0" "create with hvm" "-c -H hvm -u $valid_uuid" "$test_xml"
+testme "0" "create with hvm and bits" "-c -H hvm --bits 32 -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</disk>,</disk><disk type='file' device='disk'><source file='$disk2'/><target dev='hdb' bus='ide'/></disk>,g" > "$test_xml"
+testme "0" "create multiple disks" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###',${disk1}'/><readonly,g" > "$test_xml"
+testme "0" "create (readonly)" "-c -u $valid_uuid" "$test_xml"
+
+if [ "$test_hostdev" = "yes" ]; then
+    cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</disk>,</disk><hostdev mode='subsystem' type='usb'><source><address bus='002' device='004'/></source></hostdev>,g" > "$test_xml"
+    testme "0" "create hostdev (USB)" "-c -u $valid_uuid" "$test_xml"
+
+    cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</disk>,</disk><hostdev mode='subsystem' type='pci'><source><address bus='0x00' slot='0x00' function='0x0'/></source></hostdev>,g" > "$test_xml"
+    testme "0" "create hostdev (PCI)" "-c -u $valid_uuid" "$test_xml"
+fi
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$nonexistent,g" > "$test_xml"
+testme "0" "create (non-existent disk)" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$relative_disk1,g" > "$test_xml"
+testme "0" "create (relative path)" "-c -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk2,g" > "$test_xml"
+testme "0" "replace" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$nonexistent,g" > "$test_xml"
+testme "0" "replace (non-existent disk)" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" > "$test_xml"
+testme "0" "replace (adding disk)" "-r -u $valid_uuid -f $disk2" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" > "$test_xml"
+testme "0" "replace (adding non-existent disk)" "-r -u $valid_uuid -f $nonexistent" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<disk type='block' device='cdrom'><target dev='hdc' bus='ide'/><readonly/></disk></devices>,g" > "$test_xml"
+testme "0" "disk (empty cdrom)" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<serial type='file'><source path='$tmpdir/serial.log'/><target port='0'/></serial></devices>,g" > "$test_xml"
+testme "0" "serial" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<serial type='pty'><target port='0'/></serial></devices>,g" > "$test_xml"
+testme "0" "serial (pty)" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<console type='file'><source path='$tmpdir/console.log'/><target port='0'/></console></devices>,g" > "$test_xml"
+touch "$tmpdir/console.log"
+testme "0" "console" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</devices>,<console type='pty'><target port='0'/></console></devices>,g" > "$test_xml"
+testme "0" "console (pty)" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<kernel>$tmpdir/kernel</kernel></os>,g" > "$test_xml"
+touch "$tmpdir/kernel"
+testme "0" "kernel" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<initrd>$tmpdir/initrd</initrd></os>,g" > "$test_xml"
+touch "$tmpdir/initrd"
+testme "0" "initrd" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<kernel>/boot/kernel</kernel></os>,g" > "$test_xml"
+testme "0" "kernel in /boot" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<initrd>/boot/initrd</initrd></os>,g" > "$test_xml"
+testme "0" "initrd in /boot" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<kernel>/vmlinuz</kernel></os>,g" > "$test_xml"
+testme "0" "kernel is /vmlinuz" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<initrd>/initrd/ramdisk</initrd></os>,g" > "$test_xml"
+testme "0" "initrd is /initrd/ramdisk" "-r -u $valid_uuid" "$test_xml"
+
+cat "$template_xml" | sed "s,###UUID###,$uuid,g" | sed "s,###DISK###,$disk1,g" | sed "s,</os>,<initrd>/initrd.img</initrd></os>,g" > "$test_xml"
+testme "0" "initrd is /initrd.img" "-r -u $valid_uuid" "$test_xml"
+
+testme "0" "help" "-h"
+
+echo "" >$output
+if [ "$errors" != "0" ]; then
+    echo "FAIL: $errors error(s)" >$output
+    exit 1
+fi
+echo PASS >$output