s3-talloc Change TALLOC_P() to talloc()
[nivanova/samba-autobuild/.git] / source3 / smbd / notify.c
index a2a979b776c7d7370b8755e7d353da0dce168834..a70f86df007b486f1e2e9e5fd95ef70bbab96c49 100644 (file)
@@ -1,13 +1,13 @@
 /*
-   Unix SMB/Netbios implementation.
-   Version 3.0
+   Unix SMB/CIFS implementation.
    change notify handling
    Copyright (C) Andrew Tridgell 2000
    Copyright (C) Jeremy Allison 1994-1998
+   Copyright (C) Volker Lendecke 2007
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include "includes.h"
+#include "smbd/smbd.h"
+#include "smbd/globals.h"
+#include "../librpc/gen_ndr/ndr_notify.h"
+
+struct notify_change_request {
+       struct notify_change_request *prev, *next;
+       struct files_struct *fsp;       /* backpointer for cancel by mid */
+       struct smb_request *req;
+       uint32 filter;
+       uint32 max_param;
+       void (*reply_fn)(struct smb_request *req,
+                        NTSTATUS error_code,
+                        uint8_t *buf, size_t len);
+       struct notify_mid_map *mid_map;
+       void *backend_data;
+};
 
-extern int DEBUGLEVEL;
+static void notify_fsp(files_struct *fsp, uint32 action, const char *name);
 
-static struct cnotify_fns *cnotify;
+/*
+ * For NTCancel, we need to find the notify_change_request indexed by
+ * mid. Separate list here.
+ */
+
+struct notify_mid_map {
+       struct notify_mid_map *prev, *next;
+       struct notify_change_request *req;
+       uint64_t mid;
+};
 
-/****************************************************************************
- This is the structure to queue to implement NT change
- notify. It consists of smb_size bytes stored from the
- transact command (to keep the mid, tid etc around).
- Plus the fid to examine and notify private data
-*****************************************************************************/
+static bool notify_change_record_identical(struct notify_change *c1,
+                                       struct notify_change *c2)
+{
+       /* Note this is deliberately case sensitive. */
+       if (c1->action == c2->action &&
+                       strcmp(c1->name, c2->name) == 0) {
+               return True;
+       }
+       return False;
+}
 
-struct change_notify {
-       struct change_notify *next, *prev;
-       files_struct *fsp;
-       connection_struct *conn;
-       uint32 flags;
-       char request_buf[smb_size];
-       void *change_data;
-};
+static bool notify_marshall_changes(int num_changes,
+                               uint32 max_offset,
+                               struct notify_change *changes,
+                               DATA_BLOB *final_blob)
+{
+       int i;
 
-static struct change_notify *change_notify_list;
+       if (num_changes == -1) {
+               return false;
+       }
+
+       for (i=0; i<num_changes; i++) {
+               enum ndr_err_code ndr_err;
+               struct notify_change *c;
+               struct FILE_NOTIFY_INFORMATION m;
+               DATA_BLOB blob;
+
+               /* Coalesce any identical records. */
+               while (i+1 < num_changes &&
+                       notify_change_record_identical(&changes[i],
+                                               &changes[i+1])) {
+                       i++;
+               }
+
+               c = &changes[i];
+
+               m.FileName1 = c->name;
+               m.FileNameLength = strlen_m(c->name)*2;
+               m.Action = c->action;
+               m.NextEntryOffset = (i == num_changes-1) ? 0 : ndr_size_FILE_NOTIFY_INFORMATION(&m, 0);
+
+               /*
+                * Offset to next entry, only if there is one
+                */
+
+               ndr_err = ndr_push_struct_blob(&blob, talloc_tos(), &m,
+                       (ndr_push_flags_fn_t)ndr_push_FILE_NOTIFY_INFORMATION);
+               if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+                       return false;
+               }
+
+               if (DEBUGLEVEL >= 10) {
+                       NDR_PRINT_DEBUG(FILE_NOTIFY_INFORMATION, &m);
+               }
+
+               if (!data_blob_append(talloc_tos(), final_blob,
+                                     blob.data, blob.length)) {
+                       data_blob_free(&blob);
+                       return false;
+               }
+
+               data_blob_free(&blob);
+
+               if (final_blob->length > max_offset) {
+                       /* Too much data for client. */
+                       DEBUG(10, ("Client only wanted %d bytes, trying to "
+                                  "marshall %d bytes\n", (int)max_offset,
+                                  (int)final_blob->length));
+                       return False;
+               }
+       }
+
+       return True;
+}
 
 /****************************************************************************
  Setup the common parts of the return packet and send it.
 *****************************************************************************/
-static void change_notify_reply_packet(char *inbuf, uint32 error_code)
+
+void change_notify_reply(struct smb_request *req,
+                        NTSTATUS error_code,
+                        uint32_t max_param,
+                        struct notify_change_buf *notify_buf,
+                        void (*reply_fn)(struct smb_request *req,
+                                         NTSTATUS error_code,
+                                         uint8_t *buf, size_t len))
 {
-       char outbuf[smb_size+38];
+       DATA_BLOB blob = data_blob_null;
 
-       memset(outbuf, '\0', sizeof(outbuf));
-       construct_reply_common(inbuf, outbuf);
+       if (!NT_STATUS_IS_OK(error_code)) {
+               reply_fn(req, error_code, NULL, 0);
+               return;
+       }
 
-       ERROR_NT(error_code);
+       if (max_param == 0 || notify_buf == NULL) {
+               reply_fn(req, NT_STATUS_OK, NULL, 0);
+               return;
+       }
 
-       /*
-        * Seems NT needs a transact command with an error code
-        * in it. This is a longer packet than a simple error.
-        */
-       set_message(outbuf,18,0,False);
+       if (!notify_marshall_changes(notify_buf->num_changes, max_param,
+                                       notify_buf->changes, &blob)) {
+               /*
+                * We exceed what the client is willing to accept. Send
+                * nothing.
+                */
+               data_blob_free(&blob);
+       }
 
-       if (!send_smb(smbd_server_fd(),outbuf))
-               exit_server("change_notify_reply_packet: send_smb failed.\n");
+       reply_fn(req, NT_STATUS_OK, blob.data, blob.length);
+
+       data_blob_free(&blob);
+
+       TALLOC_FREE(notify_buf->changes);
+       notify_buf->num_changes = 0;
 }
 
-/****************************************************************************
-remove an entry from the list and free it, also closing any
-directory handle if necessary
-Notice the horrible stuff we have to do because this is a singly linked list.
-*****************************************************************************/
-static void change_notify_remove(struct change_notify *cnbp)
+static void notify_callback(void *private_data, const struct notify_event *e)
 {
-       cnotify->remove_notify(cnbp->change_data);
-       DLIST_REMOVE(change_notify_list, cnbp);
-       ZERO_STRUCTP(cnbp);
-       free(cnbp);
+       files_struct *fsp = (files_struct *)private_data;
+       DEBUG(10, ("notify_callback called for %s\n", fsp_str_dbg(fsp)));
+       notify_fsp(fsp, e->action, e->path);
 }
 
+NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
+                             bool recursive)
+{
+       char *fullpath;
+       struct notify_entry e;
+       NTSTATUS status;
 
-/****************************************************************************
- Delete entries by fnum from the change notify pending queue.
-*****************************************************************************/
-void remove_pending_change_notify_requests_by_fid(files_struct *fsp)
+       SMB_ASSERT(fsp->notify == NULL);
+
+       if (!(fsp->notify = TALLOC_ZERO_P(NULL, struct notify_change_buf))) {
+               DEBUG(0, ("talloc failed\n"));
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       /* Do notify operations on the base_name. */
+       if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
+                    fsp->fsp_name->base_name) == -1) {
+               DEBUG(0, ("asprintf failed\n"));
+               TALLOC_FREE(fsp->notify);
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       ZERO_STRUCT(e);
+       e.path = fullpath;
+       e.dir_fd = fsp->fh->fd;
+       e.dir_id = fsp->file_id;
+       e.filter = filter;
+       e.subdir_filter = 0;
+       if (recursive) {
+               e.subdir_filter = filter;
+       }
+
+       status = notify_add(fsp->conn->notify_ctx, &e, notify_callback, fsp);
+       SAFE_FREE(fullpath);
+
+       return status;
+}
+
+NTSTATUS change_notify_add_request(struct smb_request *req,
+                               uint32 max_param,
+                               uint32 filter, bool recursive,
+                               struct files_struct *fsp,
+                               void (*reply_fn)(struct smb_request *req,
+                                       NTSTATUS error_code,
+                                       uint8_t *buf, size_t len))
+{
+       struct notify_change_request *request = NULL;
+       struct notify_mid_map *map = NULL;
+       struct smbd_server_connection *sconn = req->sconn;
+
+       DEBUG(10, ("change_notify_add_request: Adding request for %s: "
+                  "max_param = %d\n", fsp_str_dbg(fsp), (int)max_param));
+
+       if (!(request = talloc(NULL, struct notify_change_request))
+           || !(map = talloc(request, struct notify_mid_map))) {
+               TALLOC_FREE(request);
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       request->mid_map = map;
+       map->req = request;
+
+       request->req = talloc_move(request, &req);
+       request->max_param = max_param;
+       request->filter = filter;
+       request->fsp = fsp;
+       request->reply_fn = reply_fn;
+       request->backend_data = NULL;
+
+       DLIST_ADD_END(fsp->notify->requests, request,
+                     struct notify_change_request *);
+
+       map->mid = request->req->mid;
+       DLIST_ADD(sconn->smb1.notify_mid_maps, map);
+
+       return NT_STATUS_OK;
+}
+
+static void change_notify_remove_request(struct smbd_server_connection *sconn,
+                                        struct notify_change_request *remove_req)
 {
-       struct change_notify *cnbp, *next;
+       files_struct *fsp;
+       struct notify_change_request *req;
+
+       /*
+        * Paranoia checks, the fsp referenced must must have the request in
+        * its list of pending requests
+        */
+
+       fsp = remove_req->fsp;
+       SMB_ASSERT(fsp->notify != NULL);
 
-       for (cnbp=change_notify_list; cnbp; cnbp=next) {
-               next=cnbp->next;
-               if (cnbp->fsp->fnum == fsp->fnum) {
-                       change_notify_remove(cnbp);
+       for (req = fsp->notify->requests; req; req = req->next) {
+               if (req == remove_req) {
+                       break;
                }
        }
+
+       if (req == NULL) {
+               smb_panic("notify_req not found in fsp's requests");
+       }
+
+       DLIST_REMOVE(fsp->notify->requests, req);
+       DLIST_REMOVE(sconn->smb1.notify_mid_maps, req->mid_map);
+       TALLOC_FREE(req);
 }
 
 /****************************************************************************
  Delete entries by mid from the change notify pending queue. Always send reply.
 *****************************************************************************/
-void remove_pending_change_notify_requests_by_mid(int mid)
+
+void remove_pending_change_notify_requests_by_mid(
+       struct smbd_server_connection *sconn, uint64_t mid)
 {
-       struct change_notify *cnbp, *next;
+       struct notify_mid_map *map;
 
-       for (cnbp=change_notify_list; cnbp; cnbp=next) {
-               next=cnbp->next;
-               if(SVAL(cnbp->request_buf,smb_mid) == mid) {
-                       change_notify_reply_packet(cnbp->request_buf,NT_STATUS_CANCELLED);
-                       change_notify_remove(cnbp);
+       for (map = sconn->smb1.notify_mid_maps; map; map = map->next) {
+               if (map->mid == mid) {
+                       break;
                }
        }
+
+       if (map == NULL) {
+               return;
+       }
+
+       change_notify_reply(map->req->req,
+                           NT_STATUS_CANCELLED, 0, NULL, map->req->reply_fn);
+       change_notify_remove_request(sconn, map->req);
 }
 
-/****************************************************************************
- Delete entries by filename and cnum from the change notify pending queue.
- Always send reply.
-*****************************************************************************/
-void remove_pending_change_notify_requests_by_filename(files_struct *fsp)
+void smbd_notify_cancel_by_smbreq(const struct smb_request *smbreq)
 {
-       struct change_notify *cnbp, *next;
+       struct smbd_server_connection *sconn = smbreq->sconn;
+       struct notify_mid_map *map;
 
-       for (cnbp=change_notify_list; cnbp; cnbp=next) {
-               next=cnbp->next;
-               /*
-                * We know it refers to the same directory if the connection number and
-                * the filename are identical.
-                */
-               if((cnbp->fsp->conn == fsp->conn) && strequal(cnbp->fsp->fsp_name,fsp->fsp_name)) {
-                       change_notify_reply_packet(cnbp->request_buf,NT_STATUS_CANCELLED);
-                       change_notify_remove(cnbp);
+       for (map = sconn->smb1.notify_mid_maps; map; map = map->next) {
+               if (map->req->req == smbreq) {
+                       break;
                }
        }
+
+       if (map == NULL) {
+               return;
+       }
+
+       change_notify_reply(map->req->req,
+                           NT_STATUS_CANCELLED, 0, NULL, map->req->reply_fn);
+       change_notify_remove_request(sconn, map->req);
 }
 
 /****************************************************************************
- Return true if there are pending change notifies.
-****************************************************************************/
-int change_notify_timeout(void)
+ Delete entries by fnum from the change notify pending queue.
+*****************************************************************************/
+
+void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
+                                                 NTSTATUS status)
 {
-       return cnotify->select_time;
+       if (fsp->notify == NULL) {
+               return;
+       }
+
+       while (fsp->notify->requests != NULL) {
+               change_notify_reply(fsp->notify->requests->req,
+                                   status, 0, NULL,
+                                   fsp->notify->requests->reply_fn);
+               change_notify_remove_request(fsp->conn->sconn,
+                                            fsp->notify->requests);
+       }
 }
 
-/****************************************************************************
- Process the change notify queue. Note that this is only called as root.
- Returns True if there are still outstanding change notify requests on the
- queue.
-*****************************************************************************/
-BOOL process_pending_change_notify_queue(time_t t)
+void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
+                 const char *path)
 {
-       struct change_notify *cnbp, *next;
-       uint16 vuid;
+       char *fullpath;
+       char *parent;
+       const char *name;
 
-       for (cnbp=change_notify_list; cnbp; cnbp=next) {
-               next=cnbp->next;
+       if (path[0] == '.' && path[1] == '/') {
+               path += 2;
+       }
+       if (parent_dirname(talloc_tos(), path, &parent, &name)) {
+               struct smb_filename smb_fname_parent;
+
+               ZERO_STRUCT(smb_fname_parent);
+               smb_fname_parent.base_name = parent;
 
-               vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID : SVAL(cnbp->request_buf,smb_uid);
-               
-               if (cnotify->check_notify(cnbp->conn, vuid, cnbp->fsp->fsp_name, cnbp->flags, cnbp->change_data, t)) {
-                       change_notify_reply_packet(cnbp->request_buf,STATUS_NOTIFY_ENUM_DIR);
-                       change_notify_remove(cnbp);
+               if (SMB_VFS_STAT(conn, &smb_fname_parent) != -1) {
+                       notify_onelevel(conn->notify_ctx, action, filter,
+                           SMB_VFS_FILE_ID_CREATE(conn, &smb_fname_parent.st),
+                           name);
                }
        }
 
-       return (change_notify_list != NULL);
+       fullpath = talloc_asprintf(talloc_tos(), "%s/%s", conn->connectpath,
+                                  path);
+       if (fullpath == NULL) {
+               DEBUG(0, ("asprintf failed\n"));
+               return;
+       }
+       notify_trigger(conn->notify_ctx, action, filter, fullpath);
+       TALLOC_FREE(fullpath);
 }
 
-/****************************************************************************
-   * Now queue an entry on the notify change list.
-   * We only need to save smb_size bytes from this incoming packet
-   * as we will always by returning a 'read the directory yourself'
-   * error.
-****************************************************************************/
-BOOL change_notify_set(char *inbuf, files_struct *fsp, connection_struct *conn, uint32 flags)
+static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
 {
-       struct change_notify *cnbp;
+       struct notify_change *change, *changes;
+       char *tmp;
 
-       if((cnbp = (struct change_notify *)malloc(sizeof(*cnbp))) == NULL) {
-               DEBUG(0,("call_nt_transact_notify_change: malloc fail !\n" ));
-               return -1;
+       if (fsp->notify == NULL) {
+               /*
+                * Nobody is waiting, don't queue
+                */
+               return;
        }
 
-       ZERO_STRUCTP(cnbp);
+       /*
+        * Someone has triggered a notify previously, queue the change for
+        * later.
+        */
 
-       memcpy(cnbp->request_buf, inbuf, smb_size);
-       cnbp->fsp = fsp;
-       cnbp->conn = conn;
-       cnbp->flags = flags;
-       cnbp->change_data = cnotify->register_notify(conn, fsp->fsp_name, flags);
-       
-       if (!cnbp->change_data) {
-               free(cnbp);
-               return False;
+       if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
+               /*
+                * The real number depends on the client buf, just provide a
+                * guard against a DoS here.  If name == NULL the CN backend is
+                * alerting us to a problem.  Possibly dropped events.  Clear
+                * queued changes and send the catch-all response to the client
+                * if a request is pending.
+                */
+               TALLOC_FREE(fsp->notify->changes);
+               fsp->notify->num_changes = -1;
+               if (fsp->notify->requests != NULL) {
+                       change_notify_reply(fsp->notify->requests->req,
+                                           NT_STATUS_OK,
+                                           fsp->notify->requests->max_param,
+                                           fsp->notify,
+                                           fsp->notify->requests->reply_fn);
+                       change_notify_remove_request(fsp->conn->sconn,
+                                                    fsp->notify->requests);
+               }
+               return;
        }
 
-       DLIST_ADD(change_notify_list, cnbp);
+       /* If we've exceeded the server side queue or received a NULL name
+        * from the underlying CN implementation, don't queue up any more
+        * requests until we can send a catch-all response to the client */
+       if (fsp->notify->num_changes == -1) {
+               return;
+       }
 
-       return True;
+       if (!(changes = talloc_realloc(
+                     fsp->notify, fsp->notify->changes,
+                     struct notify_change, fsp->notify->num_changes+1))) {
+               DEBUG(0, ("talloc_realloc failed\n"));
+               return;
+       }
+
+       fsp->notify->changes = changes;
+
+       change = &(fsp->notify->changes[fsp->notify->num_changes]);
+
+       if (!(tmp = talloc_strdup(changes, name))) {
+               DEBUG(0, ("talloc_strdup failed\n"));
+               return;
+       }
+
+       string_replace(tmp, '/', '\\');
+       change->name = tmp;     
+
+       change->action = action;
+       fsp->notify->num_changes += 1;
+
+       if (fsp->notify->requests == NULL) {
+               /*
+                * Nobody is waiting, so don't send anything. The ot
+                */
+               return;
+       }
+
+       if (action == NOTIFY_ACTION_OLD_NAME) {
+               /*
+                * We have to send the two rename events in one reply. So hold
+                * the first part back.
+                */
+               return;
+       }
+
+       /*
+        * Someone is waiting for the change, trigger the reply immediately.
+        *
+        * TODO: do we have to walk the lists of requests pending?
+        */
+
+       change_notify_reply(fsp->notify->requests->req,
+                           NT_STATUS_OK,
+                           fsp->notify->requests->max_param,
+                           fsp->notify,
+                           fsp->notify->requests->reply_fn);
+
+       change_notify_remove_request(fsp->conn->sconn, fsp->notify->requests);
 }
 
+char *notify_filter_string(TALLOC_CTX *mem_ctx, uint32 filter)
+{
+       char *result = NULL;
+
+       result = talloc_strdup(mem_ctx, "");
+
+       if (filter & FILE_NOTIFY_CHANGE_FILE_NAME)
+               result = talloc_asprintf_append(result, "FILE_NAME|");
+       if (filter & FILE_NOTIFY_CHANGE_DIR_NAME)
+               result = talloc_asprintf_append(result, "DIR_NAME|");
+       if (filter & FILE_NOTIFY_CHANGE_ATTRIBUTES)
+               result = talloc_asprintf_append(result, "ATTRIBUTES|");
+       if (filter & FILE_NOTIFY_CHANGE_SIZE)
+               result = talloc_asprintf_append(result, "SIZE|");
+       if (filter & FILE_NOTIFY_CHANGE_LAST_WRITE)
+               result = talloc_asprintf_append(result, "LAST_WRITE|");
+       if (filter & FILE_NOTIFY_CHANGE_LAST_ACCESS)
+               result = talloc_asprintf_append(result, "LAST_ACCESS|");
+       if (filter & FILE_NOTIFY_CHANGE_CREATION)
+               result = talloc_asprintf_append(result, "CREATION|");
+       if (filter & FILE_NOTIFY_CHANGE_EA)
+               result = talloc_asprintf_append(result, "EA|");
+       if (filter & FILE_NOTIFY_CHANGE_SECURITY)
+               result = talloc_asprintf_append(result, "SECURITY|");
+       if (filter & FILE_NOTIFY_CHANGE_STREAM_NAME)
+               result = talloc_asprintf_append(result, "STREAM_NAME|");
+       if (filter & FILE_NOTIFY_CHANGE_STREAM_SIZE)
+               result = talloc_asprintf_append(result, "STREAM_SIZE|");
+       if (filter & FILE_NOTIFY_CHANGE_STREAM_WRITE)
+               result = talloc_asprintf_append(result, "STREAM_WRITE|");
+
+       if (result == NULL) return NULL;
+       if (*result == '\0') return result;
+
+       result[strlen(result)-1] = '\0';
+       return result;
+}
 
-/****************************************************************************
-initialise the change notify subsystem
-****************************************************************************/
-BOOL init_change_notify(void)
+struct sys_notify_context *sys_notify_context_create(connection_struct *conn,
+                                                    TALLOC_CTX *mem_ctx, 
+                                                    struct event_context *ev)
 {
-#if HAVE_KERNEL_CHANGE_NOTIFY
-       cnotify = kernel_notify_init();
-#endif
-       if (!cnotify) cnotify = hash_notify_init();
-       
-       if (!cnotify) {
-               DEBUG(0,("Failed to init change notify system\n"));
-               return False;
+       struct sys_notify_context *ctx;
+
+       if (!(ctx = talloc(mem_ctx, struct sys_notify_context))) {
+               DEBUG(0, ("talloc failed\n"));
+               return NULL;
        }
 
-       return True;
+       ctx->ev = ev;
+       ctx->conn = conn;
+       ctx->private_data = NULL;
+       return ctx;
 }
+
+NTSTATUS sys_notify_watch(struct sys_notify_context *ctx,
+                         struct notify_entry *e,
+                         void (*callback)(struct sys_notify_context *ctx, 
+                                          void *private_data,
+                                          struct notify_event *ev),
+                         void *private_data, void *handle)
+{
+       return SMB_VFS_NOTIFY_WATCH(ctx->conn, ctx, e, callback, private_data,
+                                   handle);
+}
+