File: [local] / src / usr.sbin / relayd / carp.c (download)
Revision 1.5, Fri Dec 7 17:17:00 2007 UTC (16 years, 6 months ago) by reyk
Branch: MAIN
CVS Tags: OPENBSD_4_6_BASE, OPENBSD_4_6, OPENBSD_4_5_BASE, OPENBSD_4_5, OPENBSD_4_4_BASE, OPENBSD_4_4, OPENBSD_4_3_BASE, OPENBSD_4_3 Changes since 1.4: +2 -2 lines
hoststated gets renamed to relayd. easier to type, and actually says
what the daemon does - it is a relayer that pays attention to the status
of pools of hosts; not a status checkers that happens to do some relaying
|
/* $OpenBSD: carp.c,v 1.5 2007/12/07 17:17:00 reyk Exp $ */
/*
* Copyright (c) 2006 Henning Brauer <henning@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <event.h>
#include <openssl/ssl.h>
#include "relayd.h"
struct carpgroup {
TAILQ_ENTRY(carpgroup) entry;
char *group;
int do_demote;
int changed_by;
};
TAILQ_HEAD(carpgroups, carpgroup) carpgroups =
TAILQ_HEAD_INITIALIZER(carpgroups);
struct carpgroup *carp_group_find(char *group);
int carp_demote_ioctl(char *, int);
struct carpgroup *
carp_group_find(char *group)
{
struct carpgroup *c;
TAILQ_FOREACH(c, &carpgroups, entry)
if (!strcmp(c->group, group))
return (c);
return (NULL);
}
int
carp_demote_init(char *group, int force)
{
struct carpgroup *c;
int level;
if ((c = carp_group_find(group)) == NULL) {
if ((c = calloc(1, sizeof(struct carpgroup))) == NULL) {
log_warn("carp_demote_init calloc");
return (-1);
}
if ((c->group = strdup(group)) == NULL) {
log_warn("carp_demote_init calloc");
free(c);
return (-1);
}
/* only demote if this group already is demoted */
if ((level = carp_demote_get(group)) == -1)
return (-1);
if (level > 0 || force)
c->do_demote = 1;
TAILQ_INSERT_TAIL(&carpgroups, c, entry);
}
return (0);
}
void
carp_demote_shutdown(void)
{
struct carpgroup *c;
while ((c = TAILQ_FIRST(&carpgroups)) != NULL) {
TAILQ_REMOVE(&carpgroups, c, entry);
for (; c->changed_by > 0; c->changed_by--)
if (c->do_demote)
carp_demote_ioctl(c->group, -1);
free(c->group);
free(c);
}
}
int
carp_demote_get(char *group)
{
int s;
struct ifgroupreq ifgr;
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
log_warn("carp_demote_get: socket");
return (-1);
}
bzero(&ifgr, sizeof(ifgr));
if (strlcpy(ifgr.ifgr_name, group, sizeof(ifgr.ifgr_name)) >=
sizeof(ifgr.ifgr_name)) {
log_warn("carp_demote_get: invalid group");
return (-1);
}
if (ioctl(s, SIOCGIFGATTR, (caddr_t)&ifgr) == -1) {
if (errno == ENOENT)
log_warnx("group \"%s\" does not exist", group);
else
log_warn("carp_demote_get: ioctl");
close(s);
return (-1);
}
close(s);
return ((int)ifgr.ifgr_attrib.ifg_carp_demoted);
}
int
carp_demote_set(char *group, int demote)
{
struct carpgroup *c;
if ((c = carp_group_find(group)) == NULL) {
log_warnx("carp_group_find for %s returned NULL?!", group);
return (-1);
}
if (c->changed_by + demote < 0) {
log_warnx("carp_demote_set: changed_by + demote < 0");
return (-1);
}
if (c->do_demote && carp_demote_ioctl(group, demote) == -1)
return (-1);
c->changed_by += demote;
/* enable demotion when we return to 0, i. e. all sessions up */
if (demote < 0 && c->changed_by == 0)
c->do_demote = 1;
return (0);
}
int
carp_demote_reset(char *group, int value)
{
int level;
int demote = 0;
if (value < 0) {
log_warnx("carp_demote_reset: value < 0");
return (-1);
}
if ((level = carp_demote_get(group)) == -1)
return (-1);
if (level == value)
return (0);
demote -= level;
demote += value;
if (carp_demote_ioctl(group, demote) == -1)
return (-1);
return (0);
}
int
carp_demote_ioctl(char *group, int demote)
{
int s, res;
struct ifgroupreq ifgr;
if ((s = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
log_warn("carp_demote_get: socket");
return (-1);
}
bzero(&ifgr, sizeof(ifgr));
if (strlcpy(ifgr.ifgr_name, group, sizeof(ifgr.ifgr_name)) >=
sizeof(ifgr.ifgr_name)) {
log_warn("carp_demote_ioctl: invalid group");
return (-1);
}
ifgr.ifgr_attrib.ifg_carp_demoted = demote;
if ((res = ioctl(s, SIOCSIFGATTR, (caddr_t)&ifgr)) == -1)
log_warn("unable to %s the demote state "
"of group '%s'", (demote > 0) ? "increment" : "decrement",
group);
else
log_info("%s the demote state of group '%s'",
(demote > 0) ? "incremented" : "decremented", group);
close(s);
return (res);
}