altcloud/fence-virt
3
0
Fork 1
Code Issues Pull Requests Releases Activity
8453beedfc
fence-virt/server/mcast.c
Ryan McCabe 2c909b78d8 fence_virtd: Fix select logic in listener plugins 
Don't fail causing the daemon to exit when select() fails with errors
that indicate we should retry.

Signed-off-by: Ryan McCabe <rmccabe@redhat.com>
2017-05-25 13:34:05 -04:00

627 lines
14 KiB
C
Raw Blame History

/*
Copyright Red Hat, Inc. 2006
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, 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; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 675 Mass Ave, Cambridge,
MA 02139, USA.
*/
/*
* Author: Lon Hohberger <lhh at redhat.com>
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <sys/ioctl.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netdb.h>
#include <sys/time.h>
#include <fcntl.h>
#include <errno.h>
#include <pthread.h>
#include <nss.h>
#include <libgen.h>
#include <list.h>
#include <simpleconfig.h>
#include <static_map.h>
#include <server_plugin.h>
#include <history.h>
/* Local includes */
#include "xvm.h"
#include "simple_auth.h"
#include "options.h"
#include "mcast.h"
#include "tcp.h"
#include "debug.h"
#include "fdops.h"
#define NAME "multicast"
#define VERSION "1.2"
#define MCAST_MAGIC 0xabb911a3
#define VALIDATE(info) \
do {\
if (!info || info->magic != MCAST_MAGIC)\
return -EINVAL;\
} while(0)
typedef struct _mcast_options {
char *addr;
char *key_file;
int ifindex;
int family;
unsigned int port;
unsigned int hash;
unsigned int auth;
unsigned int flags;
} mcast_options;
typedef struct _mcast_info {
uint64_t magic;
void *priv;
map_object_t *map;
history_info_t *history;
char key[MAX_KEY_LEN];
mcast_options args;
const fence_callbacks_t *cb;
ssize_t key_len;
int mc_sock;
int need_kill;
} mcast_info;
struct mcast_hostlist_arg {
map_object_t *map;
const char *src;
int fd;
};
/*
* See if we fenced this node recently (successfully)
* If so, ignore the request for a few seconds.
*
* We purge our history when the entries time out.
*/
static int
check_history(void *a, void *b) {
fence_req_t *old = a, *current = b;
if (old->request == current->request &&
old->seqno == current->seqno &&
!strcasecmp((const char *)old->domain,
(const char *)current->domain)) {
return 1;
}
return 0;
}
static int
connect_tcp(fence_req_t *req, fence_auth_type_t auth,
void *key, size_t key_len)
{
int fd = -1;
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
char buf[128];
switch(req->family) {
case PF_INET:
memset(&sin, 0, sizeof(sin));
memcpy(&sin.sin_addr, req->address,
sizeof(sin.sin_addr));
sin.sin_family = PF_INET;
fd = ipv4_connect(&sin.sin_addr, req->port,
5);
if (fd < 0) {
printf("Failed to call back\n");
return -1;
}
break;
case PF_INET6:
memset(&sin6, 0, sizeof(sin6));
memcpy(&sin6.sin6_addr, req->address,
sizeof(sin6.sin6_addr));
sin.sin_family = PF_INET6;
fd = ipv6_connect(&sin6.sin6_addr, req->port,
5);
memset(buf,0,sizeof(buf));
inet_ntop(PF_INET6, &sin6.sin6_addr, buf, sizeof(buf));
if (fd < 0) {
printf("Failed to call back %s\n", buf);
return -1;
}
break;
default:
printf("Family = %d\n", req->family);
return -1;
}
/* Noops if auth == AUTH_NONE */
if (tcp_response(fd, auth, key, key_len, 10) <= 0) {
printf("Failed to respond to challenge\n");
close(fd);
return -1;
}
if (tcp_challenge(fd, auth, key, key_len, 10) <= 0) {
printf("Remote failed challenge\n");
close(fd);
return -1;
}
return fd;
}
static int
mcast_hostlist(const char *vm_name, const char *vm_uuid,
int state, void *priv)
{
struct mcast_hostlist_arg *arg = (struct mcast_hostlist_arg *)priv;
host_state_t hinfo;
struct timeval tv;
int ret;
if (map_check(arg->map, arg->src, vm_uuid) == 0) {
/* if we don't have access to fence this VM,
* we should not see it in a hostlist either */
return 0;
}
strncpy((char *)hinfo.domain, vm_name, sizeof(hinfo.domain));
strncpy((char *)hinfo.uuid, vm_uuid, sizeof(hinfo.uuid));
hinfo.state = state;
tv.tv_sec = 1;
tv.tv_usec = 0;
ret = _write_retry(arg->fd, &hinfo, sizeof(hinfo), &tv);
if (ret == sizeof(hinfo))
return 0;
return 1;
}
static int
mcast_hostlist_begin(int fd)
{
struct timeval tv;
char val = (char)RESP_HOSTLIST;
tv.tv_sec = 1;
tv.tv_usec = 0;
return _write_retry(fd, &val, 1, &tv);
}
static int
mcast_hostlist_end(int fd)
{
host_state_t hinfo;
struct timeval tv;
int ret;
printf("Sending terminator packet\n");
memset(&hinfo, 0, sizeof(hinfo));
tv.tv_sec = 1;
tv.tv_usec = 0;
ret = _write_retry(fd, &hinfo, sizeof(hinfo), &tv);
if (ret == sizeof(hinfo))
return 0;
return 1;
}
static int
do_fence_request_tcp(fence_req_t *req, mcast_info *info)
{
char ip_addr_src[1024];
int fd = -1;
char response = 1;
struct mcast_hostlist_arg arg;
fd = connect_tcp(req, info->args.auth, info->key, info->key_len);
if (fd < 0) {
dbg_printf(2, "Could not send reply to fence request: %s\n",
strerror(errno));
goto out;
}
inet_ntop(req->family, req->address,
ip_addr_src, sizeof(ip_addr_src));
dbg_printf(2, "Request %d seqno %d src %s target %s\n",
req->request, req->seqno, ip_addr_src, req->domain);
switch(req->request) {
case FENCE_NULL:
response = info->cb->null((char *)req->domain, info->priv);
break;
case FENCE_ON:
if (map_check(info->map, ip_addr_src,
(const char *)req->domain) == 0) {
response = RESP_PERM;
break;
}
response = info->cb->on((char *)req->domain, ip_addr_src,
req->seqno, info->priv);
break;
case FENCE_OFF:
if (map_check(info->map, ip_addr_src,
(const char *)req->domain) == 0) {
response = RESP_PERM;
break;
}
response = info->cb->off((char *)req->domain, ip_addr_src,
req->seqno, info->priv);
break;
case FENCE_REBOOT:
if (map_check(info->map, ip_addr_src,
(const char *)req->domain) == 0) {
response = RESP_PERM;
break;
}
response = info->cb->reboot((char *)req->domain, ip_addr_src,
req->seqno, info->priv);
break;
case FENCE_STATUS:
if (map_check(info->map, ip_addr_src,
(const char *)req->domain) == 0) {
response = RESP_PERM;
break;
}
response = info->cb->status((char *)req->domain, info->priv);
break;
case FENCE_DEVSTATUS:
response = info->cb->devstatus(info->priv);
break;
case FENCE_HOSTLIST:
arg.map = info->map;
arg.src = ip_addr_src;
arg.fd = fd;
mcast_hostlist_begin(arg.fd);
response = info->cb->hostlist(mcast_hostlist, &arg,
info->priv);
mcast_hostlist_end(arg.fd);
break;
}
dbg_printf(3, "Sending response to caller...\n");
if (_write_retry(fd, &response, 1, NULL) < 0) {
perror("write");
}
/* XVM shotguns multicast packets, so we want to avoid
* acting on the same request multiple times if the first
* attempt was successful.
*/
history_record(info->history, req);
out:
if (fd != -1)
close(fd);
return 1;
}
static int
mcast_dispatch(listener_context_t c, struct timeval *timeout)
{
mcast_info *info;
fence_req_t data;
fd_set rfds;
struct sockaddr_in sin;
int len;
int n;
socklen_t slen;
info = (mcast_info *)c;
VALIDATE(info);
FD_ZERO(&rfds);
FD_SET(info->mc_sock, &rfds);
n = _select_retry((info->mc_sock)+1, &rfds, NULL, NULL, timeout);
if (n <= 0)
return n;
slen = sizeof(sin);
len = recvfrom(info->mc_sock, &data, sizeof(data), 0,
(struct sockaddr *)&sin, &slen);
if (len <= 0) {
perror("recvfrom");
return len;
}
swab_fence_req_t(&data);
if (!verify_request(&data, info->args.hash, info->key,
info->key_len)) {
printf("Key mismatch; dropping packet\n");
return 0;
}
printf("Request %d seqno %d domain %s\n", data.request, data.seqno,
data.domain);
if (history_check(info->history, &data) == 1) {
printf("We just did this request; dropping packet\n");
return 0;
}
switch(info->args.auth) {
case AUTH_NONE:
case AUTH_SHA1:
case AUTH_SHA256:
case AUTH_SHA512:
printf("Plain TCP request\n");
do_fence_request_tcp(&data, info);
break;
default:
printf("XXX Unhandled authentication\n");
}
return 0;
}
static int
mcast_config(config_object_t *config, mcast_options *args)
{
char value[1024];
int errors = 0;
#ifdef _MODULE
if (sc_get(config, "fence_virtd/@debug", value, sizeof(value))==0)
dset(atoi(value));
#endif
if (sc_get(config, "listeners/multicast/@key_file",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for key_file\n", value);
args->key_file = strdup(value);
} else {
args->key_file = strdup(DEFAULT_KEY_FILE);
if (!args->key_file) {
dbg_printf(1, "Failed to allocate memory\n");
return -1;
}
}
args->hash = DEFAULT_HASH;
if (sc_get(config, "listeners/multicast/@hash",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for hash\n", value);
if (!strcasecmp(value, "none")) {
args->hash = HASH_NONE;
} else if (!strcasecmp(value, "sha1")) {
args->hash = HASH_SHA1;
} else if (!strcasecmp(value, "sha256")) {
args->hash = HASH_SHA256;
} else if (!strcasecmp(value, "sha512")) {
args->hash = HASH_SHA512;
} else {
dbg_printf(1, "Unsupported hash: %s\n", value);
++errors;
}
}
args->auth = DEFAULT_AUTH;
if (sc_get(config, "listeners/multicast/@auth",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for auth\n", value);
if (!strcasecmp(value, "none")) {
args->auth = AUTH_NONE;
} else if (!strcasecmp(value, "sha1")) {
args->auth = AUTH_SHA1;
} else if (!strcasecmp(value, "sha256")) {
args->auth = AUTH_SHA256;
} else if (!strcasecmp(value, "sha512")) {
args->auth = AUTH_SHA512;
} else {
dbg_printf(1, "Unsupported auth: %s\n", value);
++errors;
}
}
args->family = PF_INET;
if (sc_get(config, "listeners/multicast/@family",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for family\n", value);
if (!strcasecmp(value, "ipv4")) {
args->family = PF_INET;
} else if (!strcasecmp(value, "ipv6")) {
args->family = PF_INET6;
} else {
dbg_printf(1, "Unsupported family: %s\n", value);
++errors;
}
}
if (sc_get(config, "listeners/multicast/@address",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for address\n", value);
args->addr = strdup(value);
} else {
if (args->family == PF_INET) {
args->addr = strdup(IPV4_MCAST_DEFAULT);
} else {
args->addr = strdup(IPV6_MCAST_DEFAULT);
}
}
if (!args->addr) {
return -1;
}
args->port = DEFAULT_MCAST_PORT;
if (sc_get(config, "listeners/multicast/@port",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for port\n", value);
args->port = atoi(value);
if (args->port <= 0) {
dbg_printf(1, "Invalid port: %s\n", value);
++errors;
}
}
args->ifindex = 0;
if (sc_get(config, "listeners/multicast/@interface",
value, sizeof(value)-1) == 0) {
dbg_printf(1, "Got %s for interface\n", value);
args->ifindex = if_nametoindex(value);
if (args->ifindex < 0) {
dbg_printf(1, "Invalid interface: %s\n", value);
++errors;
}
}
return errors;
}
static int
mcast_init(listener_context_t *c, const fence_callbacks_t *cb,
config_object_t *config, map_object_t *map, void *priv)
{
mcast_info *info;
int mc_sock, ret;
/* Initialize NSS; required to do hashing, as silly as that
sounds... */
if (NSS_NoDB_Init(NULL) != SECSuccess) {
printf("Could not initialize NSS\n");
return 1;
}
info = malloc(sizeof(*info));
if (!info)
return -1;
memset(info, 0, sizeof(*info));
info->priv = priv;
info->cb = cb;
info->map = map;
ret = mcast_config(config, &info->args);
if (ret < 0) {
perror("mcast_config");
free(info);
return -1;
} else if (ret > 0) {
printf("%d errors found during configuration\n",ret);
free(info);
return -1;
}
if (info->args.auth != AUTH_NONE || info->args.hash != HASH_NONE) {
info->key_len = read_key_file(info->args.key_file,
info->key, sizeof(info->key));
if (info->key_len < 0) {
printf("Could not read %s; operating without "
"authentication\n", info->args.key_file);
info->args.auth = AUTH_NONE;
info->args.hash = HASH_NONE;
info->key_len = 0;
}
}
if (info->args.family == PF_INET)
mc_sock = ipv4_recv_sk(info->args.addr,
info->args.port,
info->args.ifindex);
else
mc_sock = ipv6_recv_sk(info->args.addr,
info->args.port,
info->args.ifindex);
if (mc_sock < 0) {
printf("Could not set up multicast listen socket\n");
free(info);
return -1;
}
info->magic = MCAST_MAGIC;
info->mc_sock = mc_sock;
info->history = history_init(check_history, 10, sizeof(fence_req_t));
*c = (listener_context_t)info;
return 0;
}
static int
mcast_shutdown(listener_context_t c)
{
mcast_info *info = (mcast_info *)c;
VALIDATE(info);
info->magic = 0;
history_wipe(info->history);
free(info->history);
free(info->args.key_file);
free(info->args.addr);
close(info->mc_sock);
free(info);
return 0;
}
static listener_plugin_t mcast_plugin = {
.name = NAME,
.version = VERSION,
.init = mcast_init,
.dispatch = mcast_dispatch,
.cleanup = mcast_shutdown,
};
#ifdef _MODULE
double
LISTENER_VER_SYM(void)
{
return PLUGIN_VERSION_LISTENER;
}
const listener_plugin_t *
LISTENER_INFO_SYM(void)
{
return &mcast_plugin;
}
#else
static void __attribute__((constructor))
mcast_register_plugin(void)
{
plugin_reg_listener(&mcast_plugin);
}
#endif
Reference in New Issue View Git Blame Copy Permalink