If the 'service' property is not set, we'll call pam_start() with a NULL pointer for the service name. This fails and leaves a message like this in the syslog: qemu-storage-daemon[294015]: PAM pam_start: invalid argument: service == NULL Make specifying the property mandatory and catch the error already during the creation of the object. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
		
			
				
	
	
		
			154 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			154 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * QEMU PAM authorization driver
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 *
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 * Copyright (c) 2018 Red Hat, Inc.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
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 *
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 */
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#include "qemu/osdep.h"
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#include "authz/pamacct.h"
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#include "trace.h"
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#include "qemu/module.h"
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#include "qom/object_interfaces.h"
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#include <security/pam_appl.h>
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static bool qauthz_pam_is_allowed(QAuthZ *authz,
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                                  const char *identity,
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                                  Error **errp)
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{
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    QAuthZPAM *pauthz = QAUTHZ_PAM(authz);
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    const struct pam_conv pam_conversation = { 0 };
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    pam_handle_t *pamh = NULL;
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    int ret;
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    trace_qauthz_pam_check(authz, identity, pauthz->service);
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    ret = pam_start(pauthz->service,
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                    identity,
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                    &pam_conversation,
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                    &pamh);
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    if (ret != PAM_SUCCESS) {
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        error_setg(errp, "Unable to start PAM transaction: %s",
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                   pam_strerror(NULL, ret));
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        return false;
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    }
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    ret = pam_acct_mgmt(pamh, PAM_SILENT);
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    pam_end(pamh, ret);
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    if (ret != PAM_SUCCESS) {
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        error_setg(errp, "Unable to authorize user '%s': %s",
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                   identity, pam_strerror(pamh, ret));
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        return false;
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    }
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    return true;
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}
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static void
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qauthz_pam_prop_set_service(Object *obj,
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                            const char *service,
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                            Error **errp G_GNUC_UNUSED)
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{
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    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
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    g_free(pauthz->service);
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    pauthz->service = g_strdup(service);
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}
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static char *
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qauthz_pam_prop_get_service(Object *obj,
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                            Error **errp G_GNUC_UNUSED)
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{
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    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
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    return g_strdup(pauthz->service);
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}
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static void
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qauthz_pam_complete(UserCreatable *uc, Error **errp)
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{
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    QAuthZPAM *pauthz = QAUTHZ_PAM(uc);
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    if (!pauthz->service) {
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        error_setg(errp, "The 'service' property must be set");
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        return;
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    }
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}
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static void
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qauthz_pam_finalize(Object *obj)
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{
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    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
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    g_free(pauthz->service);
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}
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static void
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qauthz_pam_class_init(ObjectClass *oc, void *data)
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{
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    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
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    QAuthZClass *authz = QAUTHZ_CLASS(oc);
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    ucc->complete = qauthz_pam_complete;
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    authz->is_allowed = qauthz_pam_is_allowed;
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    object_class_property_add_str(oc, "service",
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                                  qauthz_pam_prop_get_service,
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                                  qauthz_pam_prop_set_service);
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}
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QAuthZPAM *qauthz_pam_new(const char *id,
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                          const char *service,
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                          Error **errp)
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{
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    return QAUTHZ_PAM(
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        object_new_with_props(TYPE_QAUTHZ_PAM,
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                              object_get_objects_root(),
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                              id, errp,
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                              "service", service,
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                              NULL));
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}
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static const TypeInfo qauthz_pam_info = {
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    .parent = TYPE_QAUTHZ,
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    .name = TYPE_QAUTHZ_PAM,
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    .instance_size = sizeof(QAuthZPAM),
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    .instance_finalize = qauthz_pam_finalize,
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    .class_init = qauthz_pam_class_init,
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    .interfaces = (InterfaceInfo[]) {
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        { TYPE_USER_CREATABLE },
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        { }
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    }
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};
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static void
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qauthz_pam_register_types(void)
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{
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    type_register_static(&qauthz_pam_info);
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}
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type_init(qauthz_pam_register_types);
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