source3/smbd/smbd_cleanupd.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  *
   4  * Copyright (C) Volker Lendecke 2015
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21 #include "smbd_cleanupd.h"
  22 #include "lib/util_procid.h"
  23 #include "lib/util/tevent_ntstatus.h"
  24 #include "lib/util/debug.h"
  25 #include "smbprofile.h"
  26 #include "serverid.h"
  27 #include "locking/proto.h"
  28 #include "cleanupdb.h"
  29
  30 struct smbd_cleanupd_state {
  31         pid_t parent_pid;
  32 };
  33
  34 static void smbd_cleanupd_shutdown(struct messaging_context *msg,
  35                                    void *private_data, uint32_t msg_type,
  36                                    struct server_id server_id,
  37                                    DATA_BLOB *data);
  38 static void smbd_cleanupd_process_exited(struct messaging_context *msg,
  39                                          void *private_data, uint32_t msg_type,
  40                                          struct server_id server_id,
  41                                          DATA_BLOB *data);
  42 static void smbd_cleanupd_unlock(struct messaging_context *msg,
  43                                  void *private_data, uint32_t msg_type,
  44                                  struct server_id server_id,
  45                                  DATA_BLOB *data);
  46
  47 struct tevent_req *smbd_cleanupd_send(TALLOC_CTX *mem_ctx,
  48                                       struct tevent_context *ev,
  49                                       struct messaging_context *msg,
  50                                       pid_t parent_pid)
  51 {
  52         struct tevent_req *req;
  53         struct smbd_cleanupd_state *state;
  54         NTSTATUS status;
  55
  56         req = tevent_req_create(mem_ctx, &state, struct smbd_cleanupd_state);
  57         if (req == NULL) {
  58                 return NULL;
  59         }
  60         state->parent_pid = parent_pid;
  61
  62         status = messaging_register(msg, req, MSG_SHUTDOWN,
  63                                     smbd_cleanupd_shutdown);
  64         if (tevent_req_nterror(req, status)) {
  65                 return tevent_req_post(req, ev);
  66         }
  67
  68         status = messaging_register(msg, req, MSG_SMB_NOTIFY_CLEANUP,
  69                                     smbd_cleanupd_process_exited);
  70         if (tevent_req_nterror(req, status)) {
  71                 return tevent_req_post(req, ev);
  72         }
  73
  74         status = messaging_register(msg, NULL, MSG_SMB_UNLOCK,
  75                                     smbd_cleanupd_unlock);
  76         if (tevent_req_nterror(req, status)) {
  77                 return tevent_req_post(req, ev);
  78         }
  79
  80         return req;
  81 }
  82
  83 static void smbd_cleanupd_shutdown(struct messaging_context *msg,
  84                                    void *private_data, uint32_t msg_type,
  85                                    struct server_id server_id,
  86                                    DATA_BLOB *data)
  87 {
  88         struct tevent_req *req = talloc_get_type_abort(
  89                 private_data, struct tevent_req);
  90         tevent_req_done(req);
  91 }
  92
  93 static void smbd_cleanupd_unlock(struct messaging_context *msg,
  94                                  void *private_data, uint32_t msg_type,
  95                                  struct server_id server_id,
  96                                  DATA_BLOB *data)
  97 {
  98         DBG_WARNING("Cleaning up brl and lock database after unclean "
  99                     "shutdown\n");
 100
 101         message_send_all(msg, MSG_SMB_UNLOCK, NULL, 0, NULL);
 102
 103         brl_revalidate(msg, private_data, msg_type, server_id, data);
 104 }
 105
 106 struct cleanup_child {
 107         struct cleanup_child *prev, *next;
 108         pid_t pid;
 109         bool unclean;
 110 };
 111
 112 struct cleanupdb_traverse_state {
 113         TALLOC_CTX *mem_ctx;
 114         bool ok;
 115         struct cleanup_child *childs;
 116 };
 117
 118 static int cleanupdb_traverse_fn(const pid_t pid,
 119                                  const bool unclean,
 120                                  void *private_data)
 121 {
 122         struct cleanupdb_traverse_state *cleanup_state =
 123                 (struct cleanupdb_traverse_state *)private_data;
 124         struct cleanup_child *child = NULL;
 125
 126         child = talloc_zero(cleanup_state->mem_ctx, struct cleanup_child);
 127         if (child == NULL) {
 128                 DBG_ERR("talloc_zero failed\n");
 129                 return -1;
 130         }
 131
 132         child->pid = pid;
 133         child->unclean = unclean;
 134         DLIST_ADD(cleanup_state->childs, child);
 135
 136         return 0;
 137 }
 138
 139 static void smbd_cleanupd_process_exited(struct messaging_context *msg,
 140                                          void *private_data, uint32_t msg_type,
 141                                          struct server_id server_id,
 142                                          DATA_BLOB *data)
 143 {
 144         struct tevent_req *req = talloc_get_type_abort(
 145                 private_data, struct tevent_req);
 146         struct smbd_cleanupd_state *state = tevent_req_data(
 147                 req, struct smbd_cleanupd_state);
 148         int ret;
 149         struct cleanupdb_traverse_state cleanup_state;
 150         TALLOC_CTX *frame = talloc_stackframe();
 151         struct cleanup_child *child = NULL;
 152
 153         cleanup_state = (struct cleanupdb_traverse_state) {
 154                 .mem_ctx = frame
 155         };
 156
 157         /*
 158          * This merely collect childs in a list, whatever we're
 159          * supposed to cleanup for every child, it has to take place
 160          * *after* the db traverse in a list loop. This is to minimize
 161          * locking interaction between the traverse and writers (ie
 162          * the parent smbd).
 163          */
 164         ret = cleanupdb_traverse_read(cleanupdb_traverse_fn, &cleanup_state);
 165         if (ret < 0) {
 166                 DBG_ERR("cleanupdb_traverse_read failed\n");
 167                 TALLOC_FREE(frame);
 168                 return;
 169         }
 170
 171         if (ret == 0) {
 172                 TALLOC_FREE(frame);
 173                 return;
 174         }
 175
 176         for (child = cleanup_state.childs;
 177              child != NULL;
 178              child = child->next)
 179         {
 180                 struct server_id child_id;
 181                 bool ok;
 182
 183                 ok = cleanupdb_delete_child(child->pid);
 184                 if (!ok) {
 185                         DBG_ERR("failed to delete pid %d\n", (int)child->pid);
 186                 }
 187
 188                 /*
 189                  * Get child_id before messaging_cleanup which wipes
 190                  * the unique_id. Not that it really matters here for
 191                  * functionality (the child should have properly
 192                  * cleaned up :-)) though, but it looks nicer.
 193                  */
 194                 child_id = pid_to_procid(child->pid);
 195
 196                 smbprofile_cleanup(child->pid, state->parent_pid);
 197
 198                 ret = messaging_cleanup(msg, child->pid);
 199
 200                 if ((ret != 0) && (ret != ENOENT)) {
 201                         DBG_DEBUG("messaging_cleanup returned %s\n",
 202                                   strerror(ret));
 203                 }
 204
 205                 if (!serverid_deregister(child_id)) {
 206                         DBG_ERR("Could not remove pid %d from serverid.tdb\n",
 207                                 (int)child->pid);
 208                 }
 209
 210                 DBG_DEBUG("cleaned up pid %d\n", (int)child->pid);
 211         }
 212
 213         TALLOC_FREE(frame);
 214 }
 215
 216 NTSTATUS smbd_cleanupd_recv(struct tevent_req *req)
 217 {
 218         return tevent_req_simple_recv_ntstatus(req);
 219 }