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/*
Unix SMB/CIFS implementation.
process model: standard (1 process per client connection)
Copyright (C) Andrew Tridgell 1992-2005
Copyright (C) James J Myers 2003 <myersjj@samba.org>
Copyright (C) Stefan (metze) Metzmacher 2004
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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "lib/events/events.h"
#include "smbd/process_model.h"
#include "system/filesys.h"
#include "cluster/cluster.h"
#include "param/param.h"
#include "ldb_wrap.h"
NTSTATUS process_model_standard_init(void);
/* we hold a pipe open in the parent, and the any child
processes wait for EOF on that pipe. This ensures that
children die when the parent dies */
static int child_pipe[2];
/*
called when the process model is selected
*/
static void standard_model_init(void)
{
pipe(child_pipe);
signal(SIGCHLD, SIG_IGN);
}
/*
handle EOF on the child pipe
*/
static void standard_pipe_handler(struct tevent_context *event_ctx, struct tevent_fd *fde,
uint16_t flags, void *private_data)
{
DEBUG(10,("Child %d exiting\n", (int)getpid()));
exit(0);
}
/*
called when a listening socket becomes readable.
*/
static void standard_accept_connection(struct tevent_context *ev,
struct loadparm_context *lp_ctx,
struct socket_context *sock,
void (*new_conn)(struct tevent_context *,
struct loadparm_context *, struct socket_context *,
struct server_id , void *),
void *private_data)
{
NTSTATUS status;
struct socket_context *sock2;
pid_t pid;
struct socket_address *c, *s;
/* accept an incoming connection. */
status = socket_accept(sock, &sock2);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0,("standard_accept_connection: accept: %s\n",
nt_errstr(status)));
/* this looks strange, but is correct. We need to throttle things until
the system clears enough resources to handle this new socket */
sleep(1);
return;
}
pid = fork();
if (pid != 0) {
/* parent or error code ... */
talloc_free(sock2);
/* go back to the event loop */
return;
}
pid = getpid();
/* This is now the child code. We need a completely new event_context to work with */
if (tevent_re_initialise(ev) != 0) {
smb_panic("Failed to re-initialise tevent after fork");
}
/* this will free all the listening sockets and all state that
is not associated with this new connection */
talloc_free(sock);
/* we don't care if the dup fails, as its only a select()
speed optimisation */
socket_dup(sock2);
/* tdb needs special fork handling */
ldb_wrap_fork_hook();
tevent_add_fd(ev, ev, child_pipe[0], TEVENT_FD_READ,
standard_pipe_handler, NULL);
close(child_pipe[1]);
/* Ensure that the forked children do not expose identical random streams */
set_need_random_reseed();
/* setup the process title */
c = socket_get_peer_addr(sock2, ev);
s = socket_get_my_addr(sock2, ev);
if (s && c) {
setproctitle("conn c[%s:%u] s[%s:%u] server_id[%d]",
c->addr, c->port, s->addr, s->port, (int)pid);
}
talloc_free(c);
talloc_free(s);
/* setup this new connection. Cluster ID is PID based for this process model */
new_conn(ev, lp_ctx, sock2, cluster_id(pid, 0), private_data);
/* we can't return to the top level here, as that event context is gone,
so we now process events in the new event context until there are no
more to process */
tevent_loop_wait(ev);
talloc_free(ev);
exit(0);
}
/*
called to create a new server task
*/
static void standard_new_task(struct tevent_context *ev,
struct loadparm_context *lp_ctx,
const char *service_name,
void (*new_task)(struct tevent_context *, struct loadparm_context *lp_ctx, struct server_id , void *),
void *private_data)
{
pid_t pid;
pid = fork();
if (pid != 0) {
/* parent or error code ... go back to the event loop */
return;
}
pid = getpid();
/* this will free all the listening sockets and all state that
is not associated with this new connection */
if (tevent_re_initialise(ev) != 0) {
smb_panic("Failed to re-initialise tevent after fork");
}
/* ldb/tdb need special fork handling */
ldb_wrap_fork_hook();
tevent_add_fd(ev, ev, child_pipe[0], TEVENT_FD_READ,
standard_pipe_handler, NULL);
close(child_pipe[1]);
/* Ensure that the forked children do not expose identical random streams */
set_need_random_reseed();
setproctitle("task %s server_id[%d]", service_name, (int)pid);
/* setup this new task. Cluster ID is PID based for this process model */
new_task(ev, lp_ctx, cluster_id(pid, 0), private_data);
/* we can't return to the top level here, as that event context is gone,
so we now process events in the new event context until there are no
more to process */
tevent_loop_wait(ev);
talloc_free(ev);
exit(0);
}
/* called when a task goes down */
_NORETURN_ static void standard_terminate(struct tevent_context *ev, struct loadparm_context *lp_ctx,
const char *reason)
{
DEBUG(2,("standard_terminate: reason[%s]\n",reason));
talloc_free(ev);
/* this reload_charcnv() has the effect of freeing the iconv context memory,
which makes leak checking easier */
reload_charcnv(lp_ctx);
/* terminate this process */
exit(0);
}
/* called to set a title of a task or connection */
static void standard_set_title(struct tevent_context *ev, const char *title)
{
if (title) {
setproctitle("%s", title);
} else {
setproctitle(NULL);
}
}
static const struct model_ops standard_ops = {
.name = "standard",
.model_init = standard_model_init,
.accept_connection = standard_accept_connection,
.new_task = standard_new_task,
.terminate = standard_terminate,
.set_title = standard_set_title,
};
/*
initialise the standard process model, registering ourselves with the process model subsystem
*/
NTSTATUS process_model_standard_init(void)
{
return register_process_model(&standard_ops);
}
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