fence-virt/client/mcast.c
Lon Hohberger 200eab4149 Make listen() retry
Pacemaker requires this in order to operate.  Multiple fencing requests
will not come from a single host, however, it is possible that multiple
instances of fence_xvm will need to run at approximately the same time.

e.g. one 'status' or 'hostlist', one fencing action.

Signed-off-by: Lon Hohberger <lon@users.sourceforge.net>
2011-09-19 16:21:14 -04:00

376 lines
8.2 KiB
C

/*
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.
*/
/*
* @file fence_virtd.c: Implementation of server daemon for Xen virtual
* machine fencing. This uses SA AIS CKPT b.1.0 checkpointing API to
* store virtual machine states.
*
* Author: Lon Hohberger <lhh at redhat.com>
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <signal.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 <libgen.h>
#include <nss.h>
/* Local includes */
#include "xvm.h"
#include "ip_lookup.h"
#include "simple_auth.h"
#include "options.h"
#include "tcp.h"
#include "mcast.h"
#include "debug.h"
#include "fdops.h"
static int
tcp_wait_connect(int lfd, int retry_tenths)
{
int fd;
fd_set rfds;
int n;
struct timeval tv;
dbg_printf(3, "Waiting for connection from XVM host daemon.\n");
FD_ZERO(&rfds);
FD_SET(lfd, &rfds);
tv.tv_sec = retry_tenths / 10;
tv.tv_usec = (retry_tenths % 10) * 100000;
n = select(lfd + 1, &rfds, NULL, NULL, &tv);
if (n == 0) {
errno = ETIMEDOUT;
return -1;
} else if (n < 0) {
return -1;
}
fd = accept(lfd, NULL, 0);
if (fd < 0)
return -1;
return fd;
}
void
do_read_hostlist(int fd, int timeout)
{
host_state_t hinfo;
fd_set rfds;
struct timeval tv;
int ret;
do {
FD_ZERO(&rfds);
FD_SET(fd, &rfds);
tv.tv_sec = timeout;
tv.tv_usec = 0;
ret = _select_retry(fd+1, &rfds, NULL, NULL, &tv);
if (ret == 0) {
printf("Timed out!\n");
break;
}
ret = _read_retry(fd, &hinfo, sizeof(hinfo), &tv);
if (ret < sizeof(hinfo)) {
printf("Bad read!\n");
break;
}
if (strlen((char *)hinfo.uuid) == 0 &&
strlen((char *)hinfo.domain) == 0)
break;
printf("%-20.20s %s %s\n", hinfo.domain, hinfo.uuid,
(hinfo.state == 0) ? "off" : "on");
} while (1);
}
static int
tcp_exchange(int fd, fence_auth_type_t auth, void *key,
size_t key_len, int timeout)
{
fd_set rfds;
struct timeval tv;
char ret = 1;
/* Ok, we're connected */
dbg_printf(3, "Issuing TCP challenge\n");
if (tcp_challenge(fd, auth, key, key_len, timeout) <= 0) {
/* Challenge failed */
printf("Invalid response to challenge\n");
return 1;
}
/* Now they'll send us one, so we need to respond here */
dbg_printf(3, "Responding to TCP challenge\n");
if (tcp_response(fd, auth, key, key_len, timeout) <= 0) {
printf("Invalid response to challenge\n");
return 1;
}
dbg_printf(2, "TCP Exchange + Authentication done... \n");
FD_ZERO(&rfds);
FD_SET(fd, &rfds);
tv.tv_sec = timeout;
tv.tv_usec = 0;
ret = 1;
dbg_printf(3, "Waiting for return value from XVM host\n");
if (_select_retry(fd + 1, &rfds, NULL, NULL, &tv) <= 0)
return -1;
/* Read return code */
if (_read_retry(fd, &ret, 1, &tv) < 0)
ret = 1;
if (ret == (char)RESP_HOSTLIST) /* hostlist */ {
do_read_hostlist(fd, timeout);
ret = 0;
}
close(fd);
return ret;
}
static int
send_multicast_packets(ip_list_t *ipl, fence_virt_args_t *args,
uint32_t seqno, void *key, size_t key_len)
{
fence_req_t freq;
int mc_sock;
ip_addr_t *ipa;
struct sockaddr_in tgt4;
struct sockaddr_in6 tgt6;
struct sockaddr *tgt;
socklen_t tgt_len;
for (ipa = ipl->tqh_first; ipa; ipa = ipa->ipa_entries.tqe_next) {
if (ipa->ipa_family != args->net.family) {
dbg_printf(2, "Ignoring %s: wrong family\n", ipa->ipa_address);
continue;
}
if (args->net.family == PF_INET) {
mc_sock = ipv4_send_sk(ipa->ipa_address, args->net.addr,
args->net.port,
(struct sockaddr *)&tgt4,
sizeof(struct sockaddr_in));
tgt = (struct sockaddr *)&tgt4;
tgt_len = sizeof(tgt4);
} else if (args->net.family == PF_INET6) {
mc_sock = ipv6_send_sk(ipa->ipa_address, args->net.addr,
args->net.port,
(struct sockaddr *)&tgt6,
sizeof(struct sockaddr_in6));
tgt = (struct sockaddr *)&tgt6;
tgt_len = sizeof(tgt6);
} else {
dbg_printf(2, "Unsupported family %d\n", args->net.family);
return -1;
}
if (mc_sock < 0)
continue;
/* Build our packet */
memset(&freq, 0, sizeof(freq));
if (args->domain && strlen((char *)args->domain)) {
strncpy((char *)freq.domain, args->domain,
sizeof(freq.domain));
}
freq.request = args->op;
freq.hashtype = args->net.hash;
freq.seqno = seqno;
/* Store source address */
if (ipa->ipa_family == PF_INET) {
freq.addrlen = sizeof(struct in_addr);
/* XXX Swap order for in_addr ? XXX */
inet_pton(PF_INET, ipa->ipa_address, freq.address);
} else if (ipa->ipa_family == PF_INET6) {
freq.addrlen = sizeof(struct in6_addr);
inet_pton(PF_INET6, ipa->ipa_address, freq.address);
}
freq.flags = 0;
if (args->flags & F_USE_UUID)
freq.flags |= RF_UUID;
freq.family = ipa->ipa_family;
freq.port = args->net.port;
sign_request(&freq, key, key_len);
dbg_printf(3, "Sending to %s via %s\n", args->net.addr,
ipa->ipa_address);
sendto(mc_sock, &freq, sizeof(freq), 0,
(struct sockaddr *)tgt, tgt_len);
close(mc_sock);
}
return 0;
}
/* TODO: Clean this up!!! */
int
mcast_fence_virt(fence_virt_args_t *args)
{
ip_list_t ipl;
char key[MAX_KEY_LEN];
struct timeval tv;
int lfd, key_len = 0, fd;
int attempts = 0;
uint32_t seqno;
/* 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;
}
if (args->net.auth != AUTH_NONE || args->net.hash != HASH_NONE) {
key_len = read_key_file(args->net.key_file, key, sizeof(key));
if (key_len < 0) {
printf("Could not read %s; trying without "
"authentication\n", args->net.key_file);
args->net.auth = AUTH_NONE;
args->net.hash = HASH_NONE;
}
}
/* Do the real work */
if (ip_build_list(&ipl) < 0) {
printf("Error building IP address list\n");
return 1;
}
attempts = args->timeout * 10 / args->retr_time;
do {
switch (args->net.auth) {
case AUTH_NONE:
case AUTH_SHA1:
case AUTH_SHA256:
case AUTH_SHA512:
if (args->net.family == PF_INET) {
lfd = ipv4_listen(args->net.port, 10);
} else {
lfd = ipv6_listen(args->net.port, 10);
}
break;
/*case AUTH_X509:*/
/* XXX Setup SSL listener socket here */
default:
return 1;
}
if (lfd < 0) {
printf("Failed to listen: %s\n", strerror(errno));
usleep(args->retr_time * 100000);
--attempts;
continue;
}
} while (0);
gettimeofday(&tv, NULL);
seqno = (uint32_t)tv.tv_usec;
do {
if (send_multicast_packets(&ipl, args, seqno,
key, key_len)) {
return -1;
}
switch (args->net.auth) {
case AUTH_NONE:
case AUTH_SHA1:
case AUTH_SHA256:
case AUTH_SHA512:
fd = tcp_wait_connect(lfd, args->retr_time);
if (fd < 0 && (errno == ETIMEDOUT ||
errno == EINTR))
continue;
break;
/* case AUTH_X509:
... = ssl_wait_connect... */
break;
default:
return 1;
}
break;
} while (--attempts);
if (fd < 0) {
if (attempts <= 0) {
printf("Timed out waiting for response\n");
return 1;
}
printf("Operation failed: %s\n", strerror(errno));
return -1;
}
switch (args->net.auth) {
case AUTH_NONE:
case AUTH_SHA1:
case AUTH_SHA256:
case AUTH_SHA512:
return tcp_exchange(fd, args->net.auth, key, key_len,
args->timeout);
break;
/* case AUTH_X509:
return ssl_exchange(...); */
default:
return 1;
}
return 1;
}