/*
- Unix SMB/Netbios implementation.
- Version 3.0
+ Unix SMB/CIFS implementation.
Samba internal messaging functions
Copyright (C) Andrew Tridgell 2000
+ Copyright (C) 2001 by Martin Pool
+ Copyright (C) 2002 by Jeremy Allison
+ Copyright (C) 2007 by Volker Lendecke
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,
*/
/**
- @file messages.c
-
- This module is used for internal messaging between Samba daemons.
+ @defgroup messages Internal messaging framework
+ @{
+ @file messages.c
+
+ @brief Module for internal messaging between Samba daemons.
The idea is that if a part of Samba wants to do communication with
another Samba process then it will do a message_register() of a
use that to reply by message_send_pid(). See ping_message() for a
simple example.
+ @caution Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
+
This system doesn't have any inherent size limitations but is not
very efficient for large messages or when messages are sent in very
quick succession.
*/
#include "includes.h"
-
-/* the locking database handle */
-static TDB_CONTEXT *tdb;
-static int received_signal;
-
-/* change the message version with any incompatible changes in the protocol */
-#define MESSAGE_VERSION 1
-
-struct message_rec {
- int msg_version;
- int msg_type;
- pid_t dest;
- pid_t src;
- size_t len;
+#include "librpc/gen_ndr/messaging.h"
+#include "librpc/gen_ndr/ndr_messaging.h"
+
+struct messaging_callback {
+ struct messaging_callback *prev, *next;
+ uint32 msg_type;
+ void (*fn)(struct messaging_context *msg, void *private_data,
+ uint32_t msg_type,
+ struct server_id server_id, DATA_BLOB *data);
+ void *private_data;
};
-/* we have a linked list of dispatch handlers */
-static struct dispatch_fns {
- struct dispatch_fns *next, *prev;
- int msg_type;
- void (*fn)(int msg_type, pid_t pid, void *buf, size_t len);
-} *dispatch_fns;
-
-/****************************************************************************
- Notifications come in as signals.
-****************************************************************************/
-
-static void sig_usr1(void)
-{
- received_signal = 1;
- sys_select_signal();
-}
-
/****************************************************************************
A useful function for testing the message system.
****************************************************************************/
-void ping_message(int msg_type, pid_t src, void *buf, size_t len)
+static void ping_message(struct messaging_context *msg_ctx,
+ void *private_data,
+ uint32_t msg_type,
+ struct server_id src,
+ DATA_BLOB *data)
{
- char *msg = buf ? buf : "none";
- DEBUG(1,("INFO: Received PING message from PID %u [%s]\n",(unsigned int)src, msg));
- message_send_pid(src, MSG_PONG, buf, len, True);
+ const char *msg = data->data ? (const char *)data->data : "none";
+
+ DEBUG(1,("INFO: Received PING message from PID %s [%s]\n",
+ procid_str_static(&src), msg));
+ messaging_send(msg_ctx, src, MSG_PONG, data);
}
/****************************************************************************
- Return current debug level.
+ Register/replace a dispatch function for a particular message type.
+ JRA changed Dec 13 2006. Only one message handler now permitted per type.
+ *NOTE*: Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
****************************************************************************/
-void debuglevel_message(int msg_type, pid_t src, void *buf, size_t len)
-{
- DEBUG(1,("INFO: Received REQ_DEBUGLEVEL message from PID %u\n",(unsigned int)src));
- message_send_pid(src, MSG_DEBUGLEVEL, DEBUGLEVEL_CLASS, sizeof(DEBUGLEVEL_CLASS), True);
-}
+struct msg_all {
+ struct messaging_context *msg_ctx;
+ int msg_type;
+ uint32 msg_flag;
+ const void *buf;
+ size_t len;
+ int n_sent;
+};
/****************************************************************************
- Initialise the messaging functions.
+ Send one of the messages for the broadcast.
****************************************************************************/
-BOOL message_init(void)
+static int traverse_fn(struct db_record *rec,
+ const struct connections_key *ckey,
+ const struct connections_data *crec,
+ void *state)
{
- if (tdb) return True;
-
- tdb = tdb_open_log(lock_path("messages.tdb"),
- 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
- O_RDWR|O_CREAT,0600);
+ struct msg_all *msg_all = (struct msg_all *)state;
+ NTSTATUS status;
- if (!tdb) {
- DEBUG(0,("ERROR: Failed to initialise messages database\n"));
- return False;
- }
+ if (crec->cnum != -1)
+ return 0;
- CatchSignal(SIGUSR1, SIGNAL_CAST sig_usr1);
+ /* Don't send if the receiver hasn't registered an interest. */
- message_register(MSG_PING, ping_message);
- message_register(MSG_REQ_DEBUGLEVEL, debuglevel_message);
+ if(!(crec->bcast_msg_flags & msg_all->msg_flag))
+ return 0;
- return True;
-}
+ /* If the msg send fails because the pid was not found (i.e. smbd died),
+ * the msg has already been deleted from the messages.tdb.*/
-/*******************************************************************
- Form a static tdb key from a pid.
-******************************************************************/
+ status = messaging_send_buf(msg_all->msg_ctx,
+ crec->pid, msg_all->msg_type,
+ (uint8 *)msg_all->buf, msg_all->len);
-static TDB_DATA message_key_pid(pid_t pid)
-{
- static char key[20];
- TDB_DATA kbuf;
-
- slprintf(key, sizeof(key)-1, "PID/%d", (int)pid);
-
- kbuf.dptr = (char *)key;
- kbuf.dsize = strlen(key)+1;
- return kbuf;
-}
+ if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
+
+ /* If the pid was not found delete the entry from connections.tdb */
-/****************************************************************************
- Notify a process that it has a message. If the process doesn't exist
- then delete its record in the database.
-****************************************************************************/
+ DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
+ procid_str_static(&crec->pid), crec->cnum,
+ crec->servicename));
-static BOOL message_notify(pid_t pid)
-{
- if (kill(pid, SIGUSR1) == -1) {
- if (errno == ESRCH) {
- DEBUG(2,("pid %d doesn't exist - deleting messages record\n", (int)pid));
- tdb_delete(tdb, message_key_pid(pid));
- } else {
- DEBUG(2,("message to process %d failed - %s\n", (int)pid, strerror(errno)));
- }
- return False;
+ rec->delete_rec(rec);
}
- return True;
+ msg_all->n_sent++;
+ return 0;
}
-/****************************************************************************
- Send a message to a particular pid.
-****************************************************************************/
-
-BOOL message_send_pid(pid_t pid, int msg_type, void *buf, size_t len, BOOL duplicates_allowed)
+/**
+ * Send a message to all smbd processes.
+ *
+ * It isn't very efficient, but should be OK for the sorts of
+ * applications that use it. When we need efficient broadcast we can add
+ * it.
+ *
+ * @param n_sent Set to the number of messages sent. This should be
+ * equal to the number of processes, but be careful for races.
+ *
+ * @retval True for success.
+ **/
+BOOL message_send_all(struct messaging_context *msg_ctx,
+ int msg_type,
+ const void *buf, size_t len,
+ int *n_sent)
{
- TDB_DATA kbuf;
- TDB_DATA dbuf;
- struct message_rec rec;
- void *p;
-
- rec.msg_version = MESSAGE_VERSION;
- rec.msg_type = msg_type;
- rec.dest = pid;
- rec.src = sys_getpid();
- rec.len = len;
-
- kbuf = message_key_pid(pid);
-
- /* lock the record for the destination */
- tdb_chainlock(tdb, kbuf);
-
- dbuf = tdb_fetch(tdb, kbuf);
-
- if (!dbuf.dptr) {
- /* its a new record */
- p = (void *)malloc(len + sizeof(rec));
- if (!p) goto failed;
-
- memcpy(p, &rec, sizeof(rec));
- if (len > 0) memcpy((void *)((char*)p+sizeof(rec)), buf, len);
+ struct msg_all msg_all;
- dbuf.dptr = p;
- dbuf.dsize = len + sizeof(rec);
- tdb_store(tdb, kbuf, dbuf, TDB_REPLACE);
- SAFE_FREE(p);
- goto ok;
- }
+ msg_all.msg_type = msg_type;
+ if (msg_type < 1000)
+ msg_all.msg_flag = FLAG_MSG_GENERAL;
+ else if (msg_type > 1000 && msg_type < 2000)
+ msg_all.msg_flag = FLAG_MSG_NMBD;
+ else if (msg_type > 2000 && msg_type < 2100)
+ msg_all.msg_flag = FLAG_MSG_PRINT_NOTIFY;
+ else if (msg_type > 2100 && msg_type < 3000)
+ msg_all.msg_flag = FLAG_MSG_PRINT_GENERAL;
+ else if (msg_type > 3000 && msg_type < 4000)
+ msg_all.msg_flag = FLAG_MSG_SMBD;
+ else
+ return False;
- if (!duplicates_allowed) {
- char *ptr;
- struct message_rec prec;
-
- for(ptr = (char *)dbuf.dptr; ptr < dbuf.dptr + dbuf.dsize; ) {
- /*
- * First check if the message header matches, then, if it's a non-zero
- * sized message, check if the data matches. If so it's a duplicate and
- * we can discard it. JRA.
- */
-
- if (!memcmp(ptr, &rec, sizeof(rec))) {
- if (!len || (len && !memcmp( ptr + sizeof(rec), (char *)buf, len))) {
- DEBUG(10,("message_send_pid: discarding duplicate message.\n"));
- SAFE_FREE(dbuf.dptr);
- tdb_chainunlock(tdb, kbuf);
- return True;
- }
- }
- memcpy(&prec, ptr, sizeof(prec));
- ptr += sizeof(rec) + prec.len;
- }
- }
+ msg_all.buf = buf;
+ msg_all.len = len;
+ msg_all.n_sent = 0;
+ msg_all.msg_ctx = msg_ctx;
- /* we're adding to an existing entry */
- p = (void *)malloc(dbuf.dsize + len + sizeof(rec));
- if (!p) goto failed;
-
- memcpy(p, dbuf.dptr, dbuf.dsize);
- memcpy((void *)((char*)p+dbuf.dsize), &rec, sizeof(rec));
- if (len > 0) memcpy((void *)((char*)p+dbuf.dsize+sizeof(rec)), buf, len);
-
- SAFE_FREE(dbuf.dptr);
- dbuf.dptr = p;
- dbuf.dsize += len + sizeof(rec);
- tdb_store(tdb, kbuf, dbuf, TDB_REPLACE);
- SAFE_FREE(dbuf.dptr);
-
- ok:
- tdb_chainunlock(tdb, kbuf);
- errno = 0; /* paranoia */
- return message_notify(pid);
-
- failed:
- tdb_chainunlock(tdb, kbuf);
- errno = 0; /* paranoia */
- return False;
+ connections_forall(traverse_fn, &msg_all);
+ if (n_sent)
+ *n_sent = msg_all.n_sent;
+ return True;
}
-/****************************************************************************
- Retrieve the next message for the current process.
-****************************************************************************/
+struct event_context *messaging_event_context(struct messaging_context *msg_ctx)
+{
+ return msg_ctx->event_ctx;
+}
-static BOOL message_recv(int *msg_type, pid_t *src, void **buf, size_t *len)
+struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
+ struct server_id server_id,
+ struct event_context *ev)
{
- TDB_DATA kbuf;
- TDB_DATA dbuf;
- struct message_rec rec;
+ struct messaging_context *ctx;
+ NTSTATUS status;
- kbuf = message_key_pid(sys_getpid());
+ if (!(ctx = TALLOC_ZERO_P(mem_ctx, struct messaging_context))) {
+ return NULL;
+ }
- tdb_chainlock(tdb, kbuf);
-
- dbuf = tdb_fetch(tdb, kbuf);
- if (dbuf.dptr == NULL || dbuf.dsize == 0) goto failed;
+ ctx->id = server_id;
+ ctx->event_ctx = ev;
- memcpy(&rec, dbuf.dptr, sizeof(rec));
+ status = messaging_tdb_init(ctx, ctx, &ctx->local);
- if (rec.msg_version != MESSAGE_VERSION) {
- DEBUG(0,("message version %d received (expected %d)\n", rec.msg_version, MESSAGE_VERSION));
- goto failed;
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("messaging_tdb_init failed: %s\n",
+ nt_errstr(status)));
+ TALLOC_FREE(ctx);
+ return NULL;
}
- if (rec.len > 0) {
- (*buf) = (void *)malloc(rec.len);
- if (!(*buf)) goto failed;
+#ifdef CLUSTER_SUPPORT
+ if (lp_clustering()) {
+ status = messaging_ctdbd_init(ctx, ctx, &ctx->remote);
- memcpy(*buf, dbuf.dptr+sizeof(rec), rec.len);
- } else {
- *buf = NULL;
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("messaging_ctdb_init failed: %s\n",
+ nt_errstr(status)));
+ TALLOC_FREE(ctx);
+ return NULL;
+ }
}
+#endif
- *len = rec.len;
- *msg_type = rec.msg_type;
- *src = rec.src;
-
- if (dbuf.dsize - (sizeof(rec)+rec.len) > 0)
- memmove(dbuf.dptr, dbuf.dptr+sizeof(rec)+rec.len, dbuf.dsize - (sizeof(rec)+rec.len));
- dbuf.dsize -= sizeof(rec)+rec.len;
+ messaging_register(ctx, NULL, MSG_PING, ping_message);
- if (dbuf.dsize == 0)
- tdb_delete(tdb, kbuf);
- else
- tdb_store(tdb, kbuf, dbuf, TDB_REPLACE);
+ /* Register some debugging related messages */
- SAFE_FREE(dbuf.dptr);
- tdb_chainunlock(tdb, kbuf);
- return True;
+ register_msg_pool_usage(ctx);
+ register_dmalloc_msgs(ctx);
+ debug_register_msgs(ctx);
- failed:
- tdb_chainunlock(tdb, kbuf);
- return False;
+ return ctx;
}
-/****************************************************************************
- Receive and dispatch any messages pending for this process.
- Notice that all dispatch handlers for a particular msg_type get called,
- so you can register multiple handlers for a message.
-****************************************************************************/
-
-void message_dispatch(void)
+/*
+ * re-init after a fork
+ */
+NTSTATUS messaging_reinit(struct messaging_context *msg_ctx)
{
- int msg_type;
- pid_t src;
- void *buf;
- size_t len;
- struct dispatch_fns *dfn;
+#ifdef CLUSTER_SUPPORT
- if (!received_signal) return;
+ TALLOC_FREE(msg_ctx->remote);
- DEBUG(10,("message_dispatch: received_signal = %d\n", received_signal));
+ if (lp_clustering()) {
+ NTSTATUS status;
- received_signal = 0;
+ status = messaging_ctdbd_init(msg_ctx, msg_ctx,
+ &msg_ctx->remote);
- while (message_recv(&msg_type, &src, &buf, &len)) {
- for (dfn = dispatch_fns; dfn; dfn = dfn->next) {
- if (dfn->msg_type == msg_type) {
- DEBUG(10,("message_dispatch: processing message of type %d.\n", msg_type));
- dfn->fn(msg_type, src, buf, len);
- }
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("messaging_ctdb_init failed: %s\n",
+ nt_errstr(status)));
+ return status;
}
- SAFE_FREE(buf);
}
+
+#endif
+
+ return NT_STATUS_OK;
}
-/****************************************************************************
- Register a dispatch function for a particular message type.
-****************************************************************************/
-void message_register(int msg_type,
- void (*fn)(int msg_type, pid_t pid, void *buf, size_t len))
+/*
+ * Register a dispatch function for a particular message type. Allow multiple
+ * registrants
+*/
+NTSTATUS messaging_register(struct messaging_context *msg_ctx,
+ void *private_data,
+ uint32_t msg_type,
+ void (*fn)(struct messaging_context *msg,
+ void *private_data,
+ uint32_t msg_type,
+ struct server_id server_id,
+ DATA_BLOB *data))
{
- struct dispatch_fns *dfn;
+ struct messaging_callback *cb;
- dfn = (struct dispatch_fns *)malloc(sizeof(*dfn));
+ /*
+ * Only one callback per type
+ */
- if (dfn != NULL) {
+ for (cb = msg_ctx->callbacks; cb != NULL; cb = cb->next) {
+ if (cb->msg_type == msg_type) {
+ cb->fn = fn;
+ cb->private_data = private_data;
+ return NT_STATUS_OK;
+ }
+ }
- ZERO_STRUCTPN(dfn);
+ if (!(cb = talloc(msg_ctx, struct messaging_callback))) {
+ return NT_STATUS_NO_MEMORY;
+ }
- dfn->msg_type = msg_type;
- dfn->fn = fn;
+ cb->msg_type = msg_type;
+ cb->fn = fn;
+ cb->private_data = private_data;
- DLIST_ADD(dispatch_fns, dfn);
- }
- else {
-
- DEBUG(0,("message_register: Not enough memory. malloc failed!\n"));
- }
+ DLIST_ADD(msg_ctx->callbacks, cb);
+ return NT_STATUS_OK;
}
-/****************************************************************************
- De-register the function for a particular message type.
-****************************************************************************/
-
-void message_deregister(int msg_type)
+/*
+ De-register the function for a particular message type.
+*/
+void messaging_deregister(struct messaging_context *ctx, uint32_t msg_type,
+ void *private_data)
{
- struct dispatch_fns *dfn, *next;
-
- for (dfn = dispatch_fns; dfn; dfn = next) {
- next = dfn->next;
- if (dfn->msg_type == msg_type) {
- DLIST_REMOVE(dispatch_fns, dfn);
- SAFE_FREE(dfn);
+ struct messaging_callback *cb, *next;
+
+ for (cb = ctx->callbacks; cb; cb = next) {
+ next = cb->next;
+ if ((cb->msg_type == msg_type)
+ && (cb->private_data == private_data)) {
+ DLIST_REMOVE(ctx->callbacks, cb);
+ TALLOC_FREE(cb);
}
- }
+ }
}
-struct msg_all {
- int msg_type;
- void *buf;
- size_t len;
- BOOL duplicates;
-};
-
-/****************************************************************************
- Send one of the messages for the broadcast.
-****************************************************************************/
-
-static int traverse_fn(TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, void *state)
+/*
+ Send a message to a particular server
+*/
+NTSTATUS messaging_send(struct messaging_context *msg_ctx,
+ struct server_id server, uint32_t msg_type,
+ const DATA_BLOB *data)
{
- struct connections_data crec;
- struct msg_all *msg_all = (struct msg_all *)state;
-
- if (dbuf.dsize != sizeof(crec))
- return 0;
-
- memcpy(&crec, dbuf.dptr, sizeof(crec));
+ return msg_ctx->local->send_fn(msg_ctx, server, msg_type, data,
+ msg_ctx->local);
+}
- if (crec.cnum != -1)
- return 0;
+NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
+ struct server_id server, uint32_t msg_type,
+ const uint8 *buf, size_t len)
+{
+ DATA_BLOB blob = data_blob_const(buf, len);
+ return messaging_send(msg_ctx, server, msg_type, &blob);
+}
- /* if the msg send fails because the pid was not found (i.e. smbd died),
- * the msg has already been deleted from the messages.tdb.*/
- if (!message_send_pid(crec.pid, msg_all->msg_type, msg_all->buf, msg_all->len,
- msg_all->duplicates)) {
-
- /* if the pid was not found delete the entry from connections.tdb */
- if (errno == ESRCH) {
- DEBUG(2,("pid %u doesn't exist - deleting connections %d [%s]\n",
- (unsigned int)crec.pid, crec.cnum, crec.name));
- tdb_delete(the_tdb, kbuf);
+/*
+ Dispatch one messsaging_rec
+*/
+void messaging_dispatch_rec(struct messaging_context *msg_ctx,
+ struct messaging_rec *rec)
+{
+ struct messaging_callback *cb, *next;
+
+ for (cb = msg_ctx->callbacks; cb != NULL; cb = next) {
+ next = cb->next;
+ if (cb->msg_type == rec->msg_type) {
+ cb->fn(msg_ctx, cb->private_data, rec->msg_type,
+ rec->src, &rec->buf);
+ return;
}
}
- return 0;
+ return;
}
-/****************************************************************************
- This is a useful function for sending messages to all smbd processes.
- It isn't very efficient, but should be OK for the sorts of applications that
- use it. When we need efficient broadcast we can add it.
-****************************************************************************/
-
-BOOL message_send_all(TDB_CONTEXT *conn_tdb, int msg_type, void *buf, size_t len, BOOL duplicates_allowed)
-{
- struct msg_all msg_all;
-
- msg_all.msg_type = msg_type;
- msg_all.buf = buf;
- msg_all.len = len;
- msg_all.duplicates = duplicates_allowed;
-
- tdb_traverse(conn_tdb, traverse_fn, &msg_all);
- return True;
-}
+/** @} **/
git.samba.org / sfrench / samba-autobuild / .git / blobdiff