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"
-static struct cnotify_fns *cnotify;
+/* Max size we can send to client in a notify response. */
+extern int max_send;
-/****************************************************************************
- 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.
-*****************************************************************************/
-
-struct change_notify {
- struct change_notify *next, *prev;
- files_struct *fsp;
- connection_struct *conn;
- uint32 flags;
+struct notify_change_request {
+ struct notify_change_request *prev, *next;
+ struct files_struct *fsp; /* backpointer for cancel by mid */
char request_buf[smb_size];
- void *change_data;
+ uint32 filter;
+ uint32 current_bufsize;
+ struct notify_mid_map *mid_map;
+ void *backend_data;
+};
+
+static void notify_fsp(files_struct *fsp, uint32 action, const char *name);
+
+static struct notify_mid_map *notify_changes_by_mid;
+
+/*
+ * 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;
+ uint16 mid;
};
-static struct change_notify *change_notify_list;
+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;
+}
+
+static BOOL notify_marshall_changes(int num_changes,
+ struct notify_change *changes,
+ prs_struct *ps)
+{
+ int i;
+ UNISTR uni_name;
+
+ for (i=0; i<num_changes; i++) {
+ struct notify_change *c;
+ size_t namelen;
+ uint32 u32_tmp; /* Temp arg to prs_uint32 to avoid
+ * signed/unsigned issues */
+
+ /* Coalesce any identical records. */
+ while (i+1 < num_changes &&
+ notify_change_record_identical(&changes[i],
+ &changes[i+1])) {
+ i++;
+ }
+
+ c = &changes[i];
+
+ namelen = convert_string_allocate(
+ NULL, CH_UNIX, CH_UTF16LE, c->name, strlen(c->name)+1,
+ &uni_name.buffer, True);
+ if ((namelen == -1) || (uni_name.buffer == NULL)) {
+ goto fail;
+ }
+
+ namelen -= 2; /* Dump NULL termination */
+
+ /*
+ * Offset to next entry, only if there is one
+ */
+
+ u32_tmp = (i == num_changes-1) ? 0 : namelen + 12;
+ if (!prs_uint32("offset", ps, 1, &u32_tmp)) goto fail;
+
+ u32_tmp = c->action;
+ if (!prs_uint32("action", ps, 1, &u32_tmp)) goto fail;
+
+ u32_tmp = namelen;
+ if (!prs_uint32("namelen", ps, 1, &u32_tmp)) goto fail;
+
+ if (!prs_unistr("name", ps, 1, &uni_name)) goto fail;
+
+ /*
+ * Not NULL terminated, decrease by the 2 UCS2 \0 chars
+ */
+ prs_set_offset(ps, prs_offset(ps)-2);
+
+ SAFE_FREE(uni_name.buffer);
+ }
+
+ return True;
+
+ fail:
+ SAFE_FREE(uni_name.buffer);
+ return False;
+}
/****************************************************************************
Setup the common parts of the return packet and send it.
*****************************************************************************/
-static void change_notify_reply_packet(char *inbuf, NTSTATUS error_code)
+static void change_notify_reply_packet(const char *request_buf,
+ NTSTATUS error_code)
{
+ const char *inbuf = request_buf;
char outbuf[smb_size+38];
memset(outbuf, '\0', sizeof(outbuf));
- construct_reply_common(inbuf, outbuf);
+ construct_reply_common(request_buf, outbuf);
ERROR_NT(error_code);
* 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);
+ set_message(inbuf,outbuf,18,0,False);
+ show_msg(outbuf);
if (!send_smb(smbd_server_fd(),outbuf))
+ exit_server_cleanly("change_notify_reply_packet: send_smb "
+ "failed.");
+}
+
+void change_notify_reply(const char *request_buf,
+ struct notify_change_buf *notify_buf)
+{
+ char *outbuf = NULL;
+ prs_struct ps;
+ size_t buflen;
+
+ if (notify_buf->num_changes == -1) {
+ change_notify_reply_packet(request_buf, NT_STATUS_OK);
+ return;
+ }
+
+ if (!prs_init(&ps, 0, NULL, False)
+ || !notify_marshall_changes(notify_buf->num_changes,
+ notify_buf->changes, &ps)) {
+ change_notify_reply_packet(request_buf, NT_STATUS_NO_MEMORY);
+ goto done;
+ }
+
+ buflen = smb_size+38+prs_offset(&ps) + 4 /* padding */;
+
+ if (buflen > max_send) {
+ /*
+ * We exceed what the client is willing to accept. Send
+ * nothing.
+ */
+ change_notify_reply_packet(request_buf, NT_STATUS_OK);
+ goto done;
+ }
+
+ if (!(outbuf = SMB_MALLOC_ARRAY(char, buflen))) {
+ change_notify_reply_packet(request_buf, NT_STATUS_NO_MEMORY);
+ goto done;
+ }
+
+ construct_reply_common(request_buf, outbuf);
+
+ if (send_nt_replies(request_buf, outbuf, buflen, NT_STATUS_OK, prs_data_p(&ps),
+ prs_offset(&ps), NULL, 0) == -1) {
exit_server("change_notify_reply_packet: send_smb failed.");
+ }
+
+ done:
+ SAFE_FREE(outbuf);
+ prs_mem_free(&ps);
+
+ 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.
-*****************************************************************************/
+static void notify_callback(void *private_data, const struct notify_event *e)
+{
+ files_struct *fsp = (files_struct *)private_data;
+ DEBUG(10, ("notify_callback called for %s\n", fsp->fsp_name));
+ notify_fsp(fsp, e->action, e->path);
+}
-static void change_notify_remove(struct change_notify *cnbp)
+NTSTATUS change_notify_create(struct files_struct *fsp, uint32 filter,
+ BOOL recursive)
{
- cnotify->remove_notify(cnbp->change_data);
- DLIST_REMOVE(change_notify_list, cnbp);
- ZERO_STRUCTP(cnbp);
- SAFE_FREE(cnbp);
+ char *fullpath;
+ struct notify_entry e;
+ NTSTATUS status;
+
+ 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;
+ }
+
+ if (asprintf(&fullpath, "%s/%s", fsp->conn->connectpath,
+ fsp->fsp_name) == -1) {
+ DEBUG(0, ("asprintf failed\n"));
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ e.path = fullpath;
+ 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;
}
-/****************************************************************************
- Delete entries by fnum from the change notify pending queue.
-*****************************************************************************/
+NTSTATUS change_notify_add_request(const char *inbuf,
+ uint32 filter, BOOL recursive,
+ struct files_struct *fsp)
+{
+ struct notify_change_request *request = NULL;
+ struct notify_mid_map *map = NULL;
-void remove_pending_change_notify_requests_by_fid(files_struct *fsp)
+ if (!(request = SMB_MALLOC_P(struct notify_change_request))
+ || !(map = SMB_MALLOC_P(struct notify_mid_map))) {
+ SAFE_FREE(request);
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ request->mid_map = map;
+ map->req = request;
+
+ memcpy(request->request_buf, inbuf, sizeof(request->request_buf));
+ request->current_bufsize = 0;
+ request->filter = filter;
+ request->fsp = fsp;
+ request->backend_data = NULL;
+
+ DLIST_ADD_END(fsp->notify->requests, request,
+ struct notify_change_request *);
+
+ map->mid = SVAL(inbuf, smb_mid);
+ DLIST_ADD(notify_changes_by_mid, map);
+
+ /* Push the MID of this packet on the signing queue. */
+ srv_defer_sign_response(SVAL(inbuf,smb_mid));
+
+ return NT_STATUS_OK;
+}
+
+static void change_notify_remove_request(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
+ */
- for (cnbp=change_notify_list; cnbp; cnbp=next) {
- next=cnbp->next;
- if (cnbp->fsp->fnum == fsp->fnum) {
- change_notify_remove(cnbp);
+ fsp = remove_req->fsp;
+ SMB_ASSERT(fsp->notify != NULL);
+
+ 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(notify_changes_by_mid, req->mid_map);
+ SAFE_FREE(req->mid_map);
+ TALLOC_FREE(req->backend_data);
+ SAFE_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(uint16 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 = notify_changes_by_mid; map; map = map->next) {
+ if (map->mid == mid) {
+ break;
}
}
+
+ if (map == NULL) {
+ return;
+ }
+
+ change_notify_reply_packet(map->req->request_buf, NT_STATUS_CANCELLED);
+ change_notify_remove_request(map->req);
}
/****************************************************************************
- Delete entries by filename and cnum from the change notify pending queue.
- Always send reply.
+ Delete entries by fnum from the change notify pending queue.
*****************************************************************************/
-void remove_pending_change_notify_requests_by_filename(files_struct *fsp)
+void remove_pending_change_notify_requests_by_fid(files_struct *fsp,
+ NTSTATUS status)
{
- struct change_notify *cnbp, *next;
+ if (fsp->notify == NULL) {
+ return;
+ }
- 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);
- }
+ while (fsp->notify->requests != NULL) {
+ change_notify_reply_packet(
+ fsp->notify->requests->request_buf, status);
+ change_notify_remove_request(fsp->notify->requests);
}
}
-/****************************************************************************
- Return true if there are pending change notifies.
-****************************************************************************/
-
-int change_notify_timeout(void)
+void notify_fname(connection_struct *conn, uint32 action, uint32 filter,
+ const char *path)
{
- return cnotify->select_time;
-}
+ char *fullpath;
-/****************************************************************************
- 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.
-*****************************************************************************/
+ if (asprintf(&fullpath, "%s/%s", conn->connectpath, path) == -1) {
+ DEBUG(0, ("asprintf failed\n"));
+ return;
+ }
+
+ notify_trigger(conn->notify_ctx, action, filter, fullpath);
+ SAFE_FREE(fullpath);
+}
-BOOL process_pending_change_notify_queue(time_t t)
+static void notify_fsp(files_struct *fsp, uint32 action, const char *name)
{
- struct change_notify *cnbp, *next;
- uint16 vuid;
+ struct notify_change *change, *changes;
+ char *tmp;
+
+ if (fsp->notify == NULL) {
+ /*
+ * Nobody is waiting, don't queue
+ */
+ return;
+ }
- for (cnbp=change_notify_list; cnbp; cnbp=next) {
- next=cnbp->next;
+ /*
+ * Someone has triggered a notify previously, queue the change for
+ * later.
+ */
- vuid = (lp_security() == SEC_SHARE) ? UID_FIELD_INVALID : SVAL(cnbp->request_buf,smb_uid);
+ if ((fsp->notify->num_changes > 1000) || (name == NULL)) {
+ /*
+ * The real number depends on the client buf, just provide a
+ * guard against a DoS here.
+ */
+ TALLOC_FREE(fsp->notify->changes);
+ fsp->notify->num_changes = -1;
+ return;
+ }
- if (cnotify->check_notify(cnbp->conn, vuid, cnbp->fsp->fsp_name, cnbp->flags, cnbp->change_data, t)) {
- DEBUG(10,("process_pending_change_notify_queue: dir %s changed !\n", cnbp->fsp->fsp_name ));
- change_notify_reply_packet(cnbp->request_buf,STATUS_NOTIFY_ENUM_DIR);
- change_notify_remove(cnbp);
- }
+ if (fsp->notify->num_changes == -1) {
+ return;
}
- return (change_notify_list != NULL);
-}
+ if (!(changes = TALLOC_REALLOC_ARRAY(
+ fsp->notify, fsp->notify->changes,
+ struct notify_change, fsp->notify->num_changes+1))) {
+ DEBUG(0, ("talloc_realloc failed\n"));
+ return;
+ }
-/****************************************************************************
- 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.
-****************************************************************************/
+ fsp->notify->changes = changes;
-BOOL change_notify_set(char *inbuf, files_struct *fsp, connection_struct *conn, uint32 flags)
-{
- struct change_notify *cnbp;
+ change = &(fsp->notify->changes[fsp->notify->num_changes]);
- if((cnbp = (struct change_notify *)malloc(sizeof(*cnbp))) == NULL) {
- DEBUG(0,("change_notify_set: malloc fail !\n" ));
- return -1;
+ if (!(tmp = talloc_strdup(changes, name))) {
+ DEBUG(0, ("talloc_strdup failed\n"));
+ return;
}
- ZERO_STRUCTP(cnbp);
+ string_replace(tmp, '/', '\\');
+ change->name = tmp;
- 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) {
- SAFE_FREE(cnbp);
- return False;
+ change->action = action;
+ fsp->notify->num_changes += 1;
+
+ if (fsp->notify->requests == NULL) {
+ /*
+ * Nobody is waiting, so don't send anything. The ot
+ */
+ return;
}
- DLIST_ADD(change_notify_list, cnbp);
+ if (action == NOTIFY_ACTION_OLD_NAME) {
+ /*
+ * We have to send the two rename events in one reply. So hold
+ * the first part back.
+ */
+ return;
+ }
- /* Push the MID of this packet on the signing queue. */
- srv_defer_sign_response(SVAL(inbuf,smb_mid), True);
+ /*
+ * Someone is waiting for the change, trigger the reply immediately.
+ *
+ * TODO: do we have to walk the lists of requests pending?
+ */
- return True;
+ change_notify_reply(fsp->notify->requests->request_buf,
+ fsp->notify);
+
+ change_notify_remove_request(fsp->notify->requests);
}
-/****************************************************************************
- Initialise the change notify subsystem.
-****************************************************************************/
+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;
+}
-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
- if (lp_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_P(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);
+}
+
git.samba.org / tprouty / samba.git / blobdiff