source3/smbd/notify_msg.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  *
   4  * Copyright (C) Volker Lendecke 2014
   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 "librpc/gen_ndr/notify.h"
  22 #include "librpc/gen_ndr/messaging.h"
  23 #include "lib/dbwrap/dbwrap.h"
  24 #include "lib/dbwrap/dbwrap_rbt.h"
  25 #include "messages.h"
  26 #include "proto.h"
  27 #include "globals.h"
  28 #include "tdb.h"
  29 #include "util_tdb.h"
  30 #include "lib/util/server_id_db.h"
  31 #include "smbd/notifyd/notifyd.h"
  32
  33 struct notify_list {
  34         struct notify_list *next, *prev;
  35         void (*callback)(void *private_data, struct timespec when,
  36                          const struct notify_event *ctx);
  37         void *private_data;
  38         char path[1];
  39 };
  40
  41 struct notify_context {
  42         struct server_id notifyd;
  43         struct messaging_context *msg_ctx;
  44         struct notify_list *list;
  45 };
  46
  47 static void notify_handler(struct messaging_context *msg, void *private_data,
  48                            uint32_t msg_type, struct server_id src,
  49                            DATA_BLOB *data);
  50
  51 struct notify_context *notify_init(TALLOC_CTX *mem_ctx,
  52                                    struct messaging_context *msg,
  53                                    struct tevent_context *ev)
  54 {
  55         struct server_id_db *names_db;
  56         struct notify_context *ctx;
  57         NTSTATUS status;
  58
  59         ctx = talloc(mem_ctx, struct notify_context);
  60         if (ctx == NULL) {
  61                 return NULL;
  62         }
  63         ctx->msg_ctx = msg;
  64         ctx->list = NULL;
  65
  66         names_db = messaging_names_db(msg);
  67         if (!server_id_db_lookup_one(names_db, "notify-daemon",
  68                                      &ctx->notifyd)) {
  69                 DEBUG(1, ("No notify daemon around\n"));
  70                 TALLOC_FREE(ctx);
  71                 return NULL;
  72         }
  73
  74         status = messaging_register(msg, ctx, MSG_PVFS_NOTIFY, notify_handler);
  75         if (!NT_STATUS_IS_OK(status)) {
  76                 DEBUG(1, ("messaging_register failed: %s\n",
  77                           nt_errstr(status)));
  78                 TALLOC_FREE(ctx);
  79                 return NULL;
  80         }
  81
  82         return ctx;
  83 }
  84
  85 static void notify_handler(struct messaging_context *msg, void *private_data,
  86                            uint32_t msg_type, struct server_id src,
  87                            DATA_BLOB *data)
  88 {
  89         struct notify_context *ctx = talloc_get_type_abort(
  90                 private_data, struct notify_context);
  91         struct notify_event_msg *event_msg;
  92         struct notify_event event;
  93         struct notify_list *listel;
  94
  95         if (data->length < offsetof(struct notify_event_msg, path) + 1) {
  96                 DEBUG(1, ("message too short: %u\n", (unsigned)data->length));
  97                 return;
  98         }
  99         if (data->data[data->length-1] != 0) {
 100                 DEBUG(1, ("%s: path not 0-terminated\n", __func__));
 101                 return;
 102         }
 103
 104         event_msg = (struct notify_event_msg *)data->data;
 105
 106         event.action = event_msg->action;
 107         event.path = event_msg->path;
 108         event.private_data = event_msg->private_data;
 109
 110         DEBUG(10, ("%s: Got notify_event action=%u, private_data=%p, "
 111                    "path=%s\n", __func__, (unsigned)event.action,
 112                    event.private_data, event.path));
 113
 114         for (listel = ctx->list; listel != NULL; listel = listel->next) {
 115                 if (listel->private_data == event.private_data) {
 116                         listel->callback(listel->private_data, event_msg->when,
 117                                          &event);
 118                         break;
 119                 }
 120         }
 121 }
 122
 123 NTSTATUS notify_add(struct notify_context *ctx,
 124                     const char *path, uint32_t filter, uint32_t subdir_filter,
 125                     void (*callback)(void *, struct timespec,
 126                                      const struct notify_event *),
 127                     void *private_data)
 128 {
 129         struct notify_list *listel;
 130         struct notify_rec_change_msg msg = {};
 131         struct iovec iov[2];
 132         size_t pathlen;
 133         NTSTATUS status;
 134
 135         if (ctx == NULL) {
 136                 return NT_STATUS_NOT_IMPLEMENTED;
 137         }
 138
 139         DEBUG(10, ("%s: path=[%s], filter=%u, subdir_filter=%u, "
 140                    "private_data=%p\n", __func__, path, (unsigned)filter,
 141                    (unsigned)subdir_filter, private_data));
 142
 143         pathlen = strlen(path)+1;
 144
 145         listel = (struct notify_list *)talloc_size(
 146                 ctx, offsetof(struct notify_list, path) + pathlen);
 147         if (listel == NULL) {
 148                 return NT_STATUS_NO_MEMORY;
 149         }
 150         listel->callback = callback;
 151         listel->private_data = private_data;
 152         memcpy(listel->path, path, pathlen);
 153
 154         clock_gettime_mono(&msg.instance.creation_time);
 155         msg.instance.filter = filter;
 156         msg.instance.subdir_filter = subdir_filter;
 157         msg.instance.private_data = private_data;
 158
 159         iov[0].iov_base = &msg;
 160         iov[0].iov_len = offsetof(struct notify_rec_change_msg, path);
 161         iov[1].iov_base = discard_const_p(char, path);
 162         iov[1].iov_len = pathlen;
 163
 164         status =  messaging_send_iov(
 165                 ctx->msg_ctx, ctx->notifyd, MSG_SMB_NOTIFY_REC_CHANGE,
 166                 iov, ARRAY_SIZE(iov), NULL, 0);
 167
 168         if (!NT_STATUS_IS_OK(status)) {
 169                 TALLOC_FREE(listel);
 170                 DEBUG(10, ("messaging_send_iov returned %s\n",
 171                            nt_errstr(status)));
 172                 return status;
 173         }
 174
 175         DLIST_ADD(ctx->list, listel);
 176         return NT_STATUS_OK;
 177 }
 178
 179 NTSTATUS notify_remove(struct notify_context *ctx, void *private_data)
 180 {
 181         struct notify_list *listel;
 182         struct notify_rec_change_msg msg = {};
 183         struct iovec iov[2];
 184         NTSTATUS status;
 185
 186         /* see if change notify is enabled at all */
 187         if (ctx == NULL) {
 188                 return NT_STATUS_NOT_IMPLEMENTED;
 189         }
 190
 191         for (listel = ctx->list; listel != NULL; listel = listel->next) {
 192                 if (listel->private_data == private_data) {
 193                         DLIST_REMOVE(ctx->list, listel);
 194                         break;
 195                 }
 196         }
 197         if (listel == NULL) {
 198                 DEBUG(10, ("%p not found\n", private_data));
 199                 return NT_STATUS_NOT_FOUND;
 200         }
 201
 202         msg.instance.private_data = private_data;
 203
 204         iov[0].iov_base = &msg;
 205         iov[0].iov_len = offsetof(struct notify_rec_change_msg, path);
 206         iov[1].iov_base = discard_const_p(char, listel->path);
 207         iov[1].iov_len = strlen(listel->path)+1;
 208
 209         status = messaging_send_iov(
 210                 ctx->msg_ctx, ctx->notifyd, MSG_SMB_NOTIFY_REC_CHANGE,
 211                 iov, ARRAY_SIZE(iov), NULL, 0);
 212
 213         TALLOC_FREE(listel);
 214         return status;
 215 }
 216
 217 void notify_trigger(struct notify_context *ctx,
 218                     uint32_t action, uint32_t filter,
 219                     const char *dir, const char *name)
 220 {
 221         struct notify_trigger_msg msg;
 222         struct iovec iov[4];
 223         char slash = '/';
 224
 225         DEBUG(10, ("notify_trigger called action=0x%x, filter=0x%x, "
 226                    "dir=%s, name=%s\n", (unsigned)action, (unsigned)filter,
 227                    dir, name));
 228
 229         if (ctx == NULL) {
 230                 return;
 231         }
 232
 233         msg.when = timespec_current();
 234         msg.action = action;
 235         msg.filter = filter;
 236
 237         iov[0].iov_base = &msg;
 238         iov[0].iov_len = offsetof(struct notify_trigger_msg, path);
 239         iov[1].iov_base = discard_const_p(char, dir);
 240         iov[1].iov_len = strlen(dir);
 241         iov[2].iov_base = &slash;
 242         iov[2].iov_len = 1;
 243         iov[3].iov_base = discard_const_p(char, name);
 244         iov[3].iov_len = strlen(name)+1;
 245
 246         messaging_send_iov(
 247                 ctx->msg_ctx, ctx->notifyd, MSG_SMB_NOTIFY_TRIGGER,
 248                 iov, ARRAY_SIZE(iov), NULL, 0);
 249 }
 250
 251 NTSTATUS notify_walk(struct notify_context *notify,
 252                      bool (*fn)(const char *path, struct server_id server,
 253                                 const struct notify_instance *instance,
 254                                 void *private_data),
 255                      void *private_data)
 256 {
 257         struct tevent_context *ev;
 258         struct tevent_req *req;
 259         struct messaging_rec *rec;
 260         uint64_t log_idx;
 261         NTSTATUS status;
 262         int ret;
 263         bool ok;
 264
 265         ev = samba_tevent_context_init(notify);
 266         if (ev == NULL) {
 267                 return NT_STATUS_NO_MEMORY;
 268         }
 269
 270         req = messaging_read_send(ev, ev, notify->msg_ctx, MSG_SMB_NOTIFY_DB);
 271         if (req == NULL) {
 272                 TALLOC_FREE(ev);
 273                 return NT_STATUS_NO_MEMORY;
 274         }
 275
 276         ok = tevent_req_set_endtime(req, ev, timeval_current_ofs(10, 0));
 277         if (!ok) {
 278                 TALLOC_FREE(ev);
 279                 return NT_STATUS_NO_MEMORY;
 280         }
 281
 282         status = messaging_send_buf(notify->msg_ctx, notify->notifyd,
 283                                     MSG_SMB_NOTIFY_GET_DB, NULL, 0);
 284         if (!NT_STATUS_IS_OK(status)) {
 285                 DEBUG(10, ("%s: messaging_send_buf failed\n",
 286                            nt_errstr(status)));
 287                 TALLOC_FREE(ev);
 288                 return status;
 289         }
 290
 291         ok = tevent_req_poll(req, ev);
 292         if (!ok) {
 293                 DEBUG(10, ("%s: tevent_req_poll failed\n", __func__));
 294                 TALLOC_FREE(ev);
 295                 return NT_STATUS_INTERNAL_ERROR;
 296         }
 297
 298         ret = messaging_read_recv(req, ev, &rec);
 299         if (ret != 0) {
 300                 DEBUG(10, ("%s: messaging_read_recv failed: %s\n",
 301                            __func__, strerror(ret)));
 302                 TALLOC_FREE(ev);
 303                 return map_nt_error_from_unix(ret);
 304         }
 305
 306         ret = notifyd_parse_db(rec->buf.data, rec->buf.length, &log_idx,
 307                                fn, private_data);
 308         if (ret != 0) {
 309                 DEBUG(10, ("%s: notifyd_parse_db failed: %s\n",
 310                            __func__, strerror(ret)));
 311                 TALLOC_FREE(ev);
 312                 return map_nt_error_from_unix(ret);
 313         }
 314
 315         TALLOC_FREE(ev);
 316         return NT_STATUS_OK;
 317 }