LXR qemu/authz/pamacct.c

   1/*
   2 * QEMU PAM authorization driver
   3 *
   4 * Copyright (c) 2018 Red Hat, Inc.
   5 *
   6 * This library is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU Lesser General Public
   8 * License as published by the Free Software Foundation; either
   9 * version 2.1 of the License, or (at your option) any later version.
  10 *
  11 * This library is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * Lesser General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU Lesser General Public
  17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18 *
  19 */
  20
  21#include "qemu/osdep.h"
  22#include "authz/pamacct.h"
  23#include "trace.h"
  24#include "qemu/module.h"
  25#include "qom/object_interfaces.h"
  26
  27#include <security/pam_appl.h>
  28
  29
  30static bool qauthz_pam_is_allowed(QAuthZ *authz,
  31                                  const char *identity,
  32                                  Error **errp)
  33{
  34    QAuthZPAM *pauthz = QAUTHZ_PAM(authz);
  35    const struct pam_conv pam_conversation = { 0 };
  36    pam_handle_t *pamh = NULL;
  37    int ret;
  38
  39    trace_qauthz_pam_check(authz, identity, pauthz->service);
  40    ret = pam_start(pauthz->service,
  41                    identity,
  42                    &pam_conversation,
  43                    &pamh);
  44    if (ret != PAM_SUCCESS) {
  45        error_setg(errp, "Unable to start PAM transaction: %s",
  46                   pam_strerror(NULL, ret));
  47        return false;
  48    }
  49
  50    ret = pam_acct_mgmt(pamh, PAM_SILENT);
  51    pam_end(pamh, ret);
  52    if (ret != PAM_SUCCESS) {
  53        error_setg(errp, "Unable to authorize user '%s': %s",
  54                   identity, pam_strerror(pamh, ret));
  55        return false;
  56    }
  57
  58    return true;
  59}
  60
  61
  62static void
  63qauthz_pam_prop_set_service(Object *obj,
  64                            const char *service,
  65                            Error **errp G_GNUC_UNUSED)
  66{
  67    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
  68
  69    g_free(pauthz->service);
  70    pauthz->service = g_strdup(service);
  71}
  72
  73
  74static char *
  75qauthz_pam_prop_get_service(Object *obj,
  76                            Error **errp G_GNUC_UNUSED)
  77{
  78    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
  79
  80    return g_strdup(pauthz->service);
  81}
  82
  83
  84static void
  85qauthz_pam_complete(UserCreatable *uc, Error **errp)
  86{
  87    QAuthZPAM *pauthz = QAUTHZ_PAM(uc);
  88
  89    if (!pauthz->service) {
  90        error_setg(errp, "The 'service' property must be set");
  91        return;
  92    }
  93}
  94
  95
  96static void
  97qauthz_pam_finalize(Object *obj)
  98{
  99    QAuthZPAM *pauthz = QAUTHZ_PAM(obj);
 100
 101    g_free(pauthz->service);
 102}
 103
 104
 105static void
 106qauthz_pam_class_init(ObjectClass *oc, void *data)
 107{
 108    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 109    QAuthZClass *authz = QAUTHZ_CLASS(oc);
 110
 111    ucc->complete = qauthz_pam_complete;
 112    authz->is_allowed = qauthz_pam_is_allowed;
 113
 114    object_class_property_add_str(oc, "service",
 115                                  qauthz_pam_prop_get_service,
 116                                  qauthz_pam_prop_set_service);
 117}
 118
 119
 120QAuthZPAM *qauthz_pam_new(const char *id,
 121                          const char *service,
 122                          Error **errp)
 123{
 124    return QAUTHZ_PAM(
 125        object_new_with_props(TYPE_QAUTHZ_PAM,
 126                              object_get_objects_root(),
 127                              id, errp,
 128                              "service", service,
 129                              NULL));
 130}
 131
 132
 133static const TypeInfo qauthz_pam_info = {
 134    .parent = TYPE_QAUTHZ,
 135    .name = TYPE_QAUTHZ_PAM,
 136    .instance_size = sizeof(QAuthZPAM),
 137    .instance_finalize = qauthz_pam_finalize,
 138    .class_init = qauthz_pam_class_init,
 139    .interfaces = (InterfaceInfo[]) {
 140        { TYPE_USER_CREATABLE },
 141        { }
 142    }
 143};
 144
 145
 146static void
 147qauthz_pam_register_types(void)
 148{
 149    type_register_static(&qauthz_pam_info);
 150}
 151
 152
 153type_init(qauthz_pam_register_types);
 154