freebsd-dev/sbin/hastd/control.c
Pawel Jakub Dawidek 32ecf62028 Setup another socketpair between parent and child, so that primary sandboxed
worker can ask the main privileged process to connect in worker's behalf
and then we can migrate descriptor using this socketpair to worker.
This is not really needed now, but will be needed once we start to use
capsicum for sandboxing.

MFC after:	1 week
2011-02-03 11:39:49 +00:00

472 lines
12 KiB
C

/*-
* Copyright (c) 2009-2010 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Pawel Jakub Dawidek under sponsorship from
* the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/wait.h>
#include <assert.h>
#include <errno.h>
#include <pthread.h>
#include <signal.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "hast.h"
#include "hastd.h"
#include "hast_proto.h"
#include "hooks.h"
#include "nv.h"
#include "pjdlog.h"
#include "proto.h"
#include "subr.h"
#include "control.h"
void
child_cleanup(struct hast_resource *res)
{
proto_close(res->hr_ctrl);
res->hr_ctrl = NULL;
if (res->hr_event != NULL) {
proto_close(res->hr_event);
res->hr_event = NULL;
}
if (res->hr_conn != NULL) {
proto_close(res->hr_conn);
res->hr_conn = NULL;
}
res->hr_workerpid = 0;
}
static void
control_set_role_common(struct hastd_config *cfg, struct nv *nvout,
uint8_t role, struct hast_resource *res, const char *name, unsigned int no)
{
int oldrole;
/* Name is always needed. */
if (name != NULL)
nv_add_string(nvout, name, "resource%u", no);
if (res == NULL) {
assert(cfg != NULL);
assert(name != NULL);
TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
if (strcmp(res->hr_name, name) == 0)
break;
}
if (res == NULL) {
nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
return;
}
}
assert(res != NULL);
/* Send previous role back. */
nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
/* Nothing changed, return here. */
if (role == res->hr_role)
return;
pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
pjdlog_info("Role changed to %s.", role2str(role));
/* Change role to the new one. */
oldrole = res->hr_role;
res->hr_role = role;
pjdlog_prefix_set("[%s] (%s) ", res->hr_name, role2str(res->hr_role));
/*
* If previous role was primary or secondary we have to kill process
* doing that work.
*/
if (res->hr_workerpid != 0) {
if (kill(res->hr_workerpid, SIGTERM) < 0) {
pjdlog_errno(LOG_WARNING,
"Unable to kill worker process %u",
(unsigned int)res->hr_workerpid);
} else if (waitpid(res->hr_workerpid, NULL, 0) !=
res->hr_workerpid) {
pjdlog_errno(LOG_WARNING,
"Error while waiting for worker process %u",
(unsigned int)res->hr_workerpid);
} else {
pjdlog_debug(1, "Worker process %u stopped.",
(unsigned int)res->hr_workerpid);
}
child_cleanup(res);
}
/* Start worker process if we are changing to primary. */
if (role == HAST_ROLE_PRIMARY)
hastd_primary(res);
pjdlog_prefix_set("%s", "");
hook_exec(res->hr_exec, "role", res->hr_name, role2str(oldrole),
role2str(res->hr_role), NULL);
}
void
control_set_role(struct hast_resource *res, uint8_t role)
{
control_set_role_common(NULL, NULL, role, res, NULL, 0);
}
static void
control_status_worker(struct hast_resource *res, struct nv *nvout,
unsigned int no)
{
struct nv *cnvin, *cnvout;
const char *str;
int error;
cnvin = cnvout = NULL;
error = 0;
/*
* Prepare and send command to worker process.
*/
cnvout = nv_alloc();
nv_add_uint8(cnvout, HASTCTL_STATUS, "cmd");
error = nv_error(cnvout);
if (error != 0) {
pjdlog_common(LOG_ERR, 0, error,
"Unable to prepare control header");
goto end;
}
if (hast_proto_send(res, res->hr_ctrl, cnvout, NULL, 0) < 0) {
error = errno;
pjdlog_errno(LOG_ERR, "Unable to send control header");
goto end;
}
/*
* Receive response.
*/
if (hast_proto_recv_hdr(res->hr_ctrl, &cnvin) < 0) {
error = errno;
pjdlog_errno(LOG_ERR, "Unable to receive control header");
goto end;
}
error = nv_get_int16(cnvin, "error");
if (error != 0)
goto end;
if ((str = nv_get_string(cnvin, "status")) == NULL) {
error = ENOENT;
pjdlog_errno(LOG_ERR, "Field 'status' is missing.");
goto end;
}
nv_add_string(nvout, str, "status%u", no);
nv_add_uint64(nvout, nv_get_uint64(cnvin, "dirty"), "dirty%u", no);
nv_add_uint32(nvout, nv_get_uint32(cnvin, "extentsize"),
"extentsize%u", no);
nv_add_uint32(nvout, nv_get_uint32(cnvin, "keepdirty"),
"keepdirty%u", no);
end:
if (cnvin != NULL)
nv_free(cnvin);
if (cnvout != NULL)
nv_free(cnvout);
if (error != 0)
nv_add_int16(nvout, error, "error");
}
static void
control_status(struct hastd_config *cfg, struct nv *nvout,
struct hast_resource *res, const char *name, unsigned int no)
{
assert(cfg != NULL);
assert(nvout != NULL);
assert(name != NULL);
/* Name is always needed. */
nv_add_string(nvout, name, "resource%u", no);
if (res == NULL) {
TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
if (strcmp(res->hr_name, name) == 0)
break;
}
if (res == NULL) {
nv_add_int16(nvout, EHAST_NOENTRY, "error%u", no);
return;
}
}
assert(res != NULL);
nv_add_string(nvout, res->hr_provname, "provname%u", no);
nv_add_string(nvout, res->hr_localpath, "localpath%u", no);
nv_add_string(nvout, res->hr_remoteaddr, "remoteaddr%u", no);
switch (res->hr_replication) {
case HAST_REPLICATION_FULLSYNC:
nv_add_string(nvout, "fullsync", "replication%u", no);
break;
case HAST_REPLICATION_MEMSYNC:
nv_add_string(nvout, "memsync", "replication%u", no);
break;
case HAST_REPLICATION_ASYNC:
nv_add_string(nvout, "async", "replication%u", no);
break;
default:
nv_add_string(nvout, "unknown", "replication%u", no);
break;
}
nv_add_string(nvout, role2str(res->hr_role), "role%u", no);
switch (res->hr_role) {
case HAST_ROLE_PRIMARY:
assert(res->hr_workerpid != 0);
/* FALLTHROUGH */
case HAST_ROLE_SECONDARY:
if (res->hr_workerpid != 0)
break;
/* FALLTHROUGH */
default:
return;
}
/*
* If we are here, it means that we have a worker process, which we
* want to ask some questions.
*/
control_status_worker(res, nvout, no);
}
void
control_handle(struct hastd_config *cfg)
{
struct proto_conn *conn;
struct nv *nvin, *nvout;
unsigned int ii;
const char *str;
uint8_t cmd, role;
int error;
if (proto_accept(cfg->hc_controlconn, &conn) < 0) {
pjdlog_errno(LOG_ERR, "Unable to accept control connection");
return;
}
cfg->hc_controlin = conn;
nvin = nvout = NULL;
role = HAST_ROLE_UNDEF;
if (hast_proto_recv_hdr(conn, &nvin) < 0) {
pjdlog_errno(LOG_ERR, "Unable to receive control header");
nvin = NULL;
goto close;
}
/* Obtain command code. 0 means that nv_get_uint8() failed. */
cmd = nv_get_uint8(nvin, "cmd");
if (cmd == 0) {
pjdlog_error("Control header is missing 'cmd' field.");
error = EHAST_INVALID;
goto close;
}
/* Allocate outgoing nv structure. */
nvout = nv_alloc();
if (nvout == NULL) {
pjdlog_error("Unable to allocate header for control response.");
error = EHAST_NOMEMORY;
goto close;
}
error = 0;
str = nv_get_string(nvin, "resource0");
if (str == NULL) {
pjdlog_error("Control header is missing 'resource0' field.");
error = EHAST_INVALID;
goto fail;
}
if (cmd == HASTCTL_SET_ROLE) {
role = nv_get_uint8(nvin, "role");
switch (role) {
case HAST_ROLE_INIT: /* Is that valid to set, hmm? */
case HAST_ROLE_PRIMARY:
case HAST_ROLE_SECONDARY:
break;
default:
pjdlog_error("Invalid role received (%hhu).", role);
error = EHAST_INVALID;
goto fail;
}
}
if (strcmp(str, "all") == 0) {
struct hast_resource *res;
/* All configured resources. */
ii = 0;
TAILQ_FOREACH(res, &cfg->hc_resources, hr_next) {
switch (cmd) {
case HASTCTL_SET_ROLE:
control_set_role_common(cfg, nvout, role, res,
res->hr_name, ii++);
break;
case HASTCTL_STATUS:
control_status(cfg, nvout, res, res->hr_name,
ii++);
break;
default:
pjdlog_error("Invalid command received (%hhu).",
cmd);
error = EHAST_UNIMPLEMENTED;
goto fail;
}
}
} else {
/* Only selected resources. */
for (ii = 0; ; ii++) {
str = nv_get_string(nvin, "resource%u", ii);
if (str == NULL)
break;
switch (cmd) {
case HASTCTL_SET_ROLE:
control_set_role_common(cfg, nvout, role, NULL,
str, ii);
break;
case HASTCTL_STATUS:
control_status(cfg, nvout, NULL, str, ii);
break;
default:
pjdlog_error("Invalid command received (%hhu).",
cmd);
error = EHAST_UNIMPLEMENTED;
goto fail;
}
}
}
if (nv_error(nvout) != 0)
goto close;
fail:
if (error != 0)
nv_add_int16(nvout, error, "error");
if (hast_proto_send(NULL, conn, nvout, NULL, 0) < 0)
pjdlog_errno(LOG_ERR, "Unable to send control response");
close:
if (nvin != NULL)
nv_free(nvin);
if (nvout != NULL)
nv_free(nvout);
proto_close(conn);
cfg->hc_controlin = NULL;
}
/*
* Thread handles control requests from the parent.
*/
void *
ctrl_thread(void *arg)
{
struct hast_resource *res = arg;
struct nv *nvin, *nvout;
uint8_t cmd;
for (;;) {
if (hast_proto_recv_hdr(res->hr_ctrl, &nvin) < 0) {
if (sigexit_received)
pthread_exit(NULL);
pjdlog_errno(LOG_ERR,
"Unable to receive control message");
kill(getpid(), SIGTERM);
pthread_exit(NULL);
}
cmd = nv_get_uint8(nvin, "cmd");
if (cmd == 0) {
pjdlog_error("Control message is missing 'cmd' field.");
nv_free(nvin);
continue;
}
nvout = nv_alloc();
switch (cmd) {
case HASTCTL_STATUS:
if (res->hr_remotein != NULL &&
res->hr_remoteout != NULL) {
nv_add_string(nvout, "complete", "status");
} else {
nv_add_string(nvout, "degraded", "status");
}
nv_add_uint32(nvout, (uint32_t)res->hr_extentsize,
"extentsize");
if (res->hr_role == HAST_ROLE_PRIMARY) {
nv_add_uint32(nvout,
(uint32_t)res->hr_keepdirty, "keepdirty");
nv_add_uint64(nvout,
(uint64_t)(activemap_ndirty(res->hr_amp) *
res->hr_extentsize), "dirty");
} else {
nv_add_uint32(nvout, (uint32_t)0, "keepdirty");
nv_add_uint64(nvout, (uint64_t)0, "dirty");
}
nv_add_int16(nvout, 0, "error");
break;
case HASTCTL_RELOAD:
/*
* When parent receives SIGHUP and discovers that
* something related to us has changes, it sends reload
* message to us.
*/
assert(res->hr_role == HAST_ROLE_PRIMARY);
primary_config_reload(res, nvin);
nv_add_int16(nvout, 0, "error");
break;
default:
nv_add_int16(nvout, EINVAL, "error");
break;
}
nv_free(nvin);
if (nv_error(nvout) != 0) {
pjdlog_error("Unable to create answer on control message.");
nv_free(nvout);
continue;
}
if (hast_proto_send(NULL, res->hr_ctrl, nvout, NULL, 0) < 0) {
pjdlog_errno(LOG_ERR,
"Unable to send reply to control message");
}
nv_free(nvout);
}
/* NOTREACHED */
return (NULL);
}