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
  43 struct tevent_req *smbd_cleanupd_send(TALLOC_CTX *mem_ctx,
  44                                       struct tevent_context *ev,
  45                                       struct messaging_context *msg,
  46                                       pid_t parent_pid)
  47 {
  48         struct tevent_req *req;
  49         struct smbd_cleanupd_state *state;
  50         NTSTATUS status;
  51
  52         req = tevent_req_create(mem_ctx, &state, struct smbd_cleanupd_state);
  53         if (req == NULL) {
  54                 return NULL;
  55         }
  56         state->parent_pid = parent_pid;
  57
  58         status = messaging_register(msg, req, MSG_SHUTDOWN,
  59                                     smbd_cleanupd_shutdown);
  60         if (tevent_req_nterror(req, status)) {
  61                 return tevent_req_post(req, ev);
  62         }
  63
  64         status = messaging_register(msg, req, MSG_SMB_NOTIFY_CLEANUP,
  65                                     smbd_cleanupd_process_exited);
  66         if (tevent_req_nterror(req, status)) {
  67                 return tevent_req_post(req, ev);
  68         }
  69
  70         return req;
  71 }
  72
  73 static void smbd_cleanupd_shutdown(struct messaging_context *msg,
  74                                    void *private_data, uint32_t msg_type,
  75                                    struct server_id server_id,
  76                                    DATA_BLOB *data)
  77 {
  78         struct tevent_req *req = talloc_get_type_abort(
  79                 private_data, struct tevent_req);
  80         tevent_req_done(req);
  81 }
  82
  83 struct cleanup_child {
  84         struct cleanup_child *prev, *next;
  85         pid_t pid;
  86         bool unclean;
  87 };
  88
  89 struct cleanupdb_traverse_state {
  90         TALLOC_CTX *mem_ctx;
  91         bool ok;
  92         struct cleanup_child *children;
  93 };
  94
  95 static int cleanupdb_traverse_fn(const pid_t pid,
  96                                  const bool unclean,
  97                                  void *private_data)
  98 {
  99         struct cleanupdb_traverse_state *cleanup_state =
 100                 (struct cleanupdb_traverse_state *)private_data;
 101         struct cleanup_child *child = NULL;
 102
 103         child = talloc_zero(cleanup_state->mem_ctx, struct cleanup_child);
 104         if (child == NULL) {
 105                 DBG_ERR("talloc_zero failed\n");
 106                 return -1;
 107         }
 108
 109         child->pid = pid;
 110         child->unclean = unclean;
 111         DLIST_ADD(cleanup_state->children, child);
 112
 113         return 0;
 114 }
 115
 116 static void smbd_cleanupd_process_exited(struct messaging_context *msg,
 117                                          void *private_data, uint32_t msg_type,
 118                                          struct server_id server_id,
 119                                          DATA_BLOB *data)
 120 {
 121         struct tevent_req *req = talloc_get_type_abort(
 122                 private_data, struct tevent_req);
 123         struct smbd_cleanupd_state *state = tevent_req_data(
 124                 req, struct smbd_cleanupd_state);
 125         int ret;
 126         struct cleanupdb_traverse_state cleanup_state;
 127         TALLOC_CTX *frame = talloc_stackframe();
 128         struct cleanup_child *child = NULL;
 129
 130         cleanup_state = (struct cleanupdb_traverse_state) {
 131                 .mem_ctx = frame
 132         };
 133
 134         /*
 135          * This merely collect children in a list, whatever we're
 136          * supposed to cleanup for every child, it has to take place
 137          * *after* the db traverse in a list loop. This is to minimize
 138          * locking interaction between the traverse and writers (i.e.
 139          * the parent smbd).
 140          */
 141         ret = cleanupdb_traverse_read(cleanupdb_traverse_fn, &cleanup_state);
 142         if (ret < 0) {
 143                 DBG_ERR("cleanupdb_traverse_read failed\n");
 144                 TALLOC_FREE(frame);
 145                 return;
 146         }
 147
 148         if (ret == 0) {
 149                 TALLOC_FREE(frame);
 150                 return;
 151         }
 152
 153         for (child = cleanup_state.children;
 154              child != NULL;
 155              child = child->next)
 156         {
 157                 bool ok;
 158
 159                 ok = cleanupdb_delete_child(child->pid);
 160                 if (!ok) {
 161                         DBG_ERR("failed to delete pid %d\n", (int)child->pid);
 162                 }
 163
 164                 smbprofile_cleanup(child->pid, state->parent_pid);
 165
 166                 ret = messaging_cleanup(msg, child->pid);
 167
 168                 if ((ret != 0) && (ret != ENOENT)) {
 169                         DBG_DEBUG("messaging_cleanup returned %s\n",
 170                                   strerror(ret));
 171                 }
 172
 173                 DBG_DEBUG("cleaned up pid %d\n", (int)child->pid);
 174         }
 175
 176         TALLOC_FREE(frame);
 177 }
 178
 179 NTSTATUS smbd_cleanupd_recv(struct tevent_req *req)
 180 {
 181         return tevent_req_simple_recv_ntstatus(req);
 182 }