OpenSolaris_b135/cmd/fs.d/autofs/nfs_cast.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* nfs_cast.c : broadcast to a specific group of NFS servers
*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <stdio.h>
#include <syslog.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include <stdlib.h>
#include <rpc/rpc.h>
#include <rpc/clnt_soc.h>
#include <rpc/nettype.h>
#include <rpc/pmap_prot.h>
#include <netconfig.h>
#include <netdir.h>
#include <nfs/nfs.h>
#define NFSCLIENT
#include <locale.h>
#include "automount.h"
#define PENALTY_WEIGHT 100000
struct tstamps {
struct tstamps *ts_next;
int ts_penalty;
int ts_inx;
int ts_rcvd;
struct timeval ts_timeval;
};
/* A list of addresses - all belonging to the same transport */
struct addrs {
struct addrs *addr_next;
struct mapfs *addr_mfs;
struct nd_addrlist *addr_addrs;
struct tstamps *addr_if_tstamps;
};
/* A list of connectionless transports */
struct transp {
struct transp *tr_next;
int tr_fd;
char *tr_device;
struct t_bind *tr_taddr;
struct addrs *tr_addrs;
};
/* A list of map entries and their roundtrip times, for sorting */
struct sm {
struct mapfs *mfs;
struct timeval timeval;
};
static void free_transports(struct transp *);
static void calc_resp_time(struct timeval *);
static struct mapfs *sort_responses(struct transp *);
static int host_sm(const void *, const void *b);
static int time_sm(const void *, const void *b);
extern struct mapfs *add_mfs(struct mapfs *, int, struct mapfs **,
struct mapfs **);
/*
* This routine is designed to be able to "ping"
* a list of hosts and create a list of responding
* hosts sorted by response time.
* This must be done without any prior
* contact with the host - therefore the "ping"
* must be to a "well-known" address. The outstanding
* candidate here is the address of "rpcbind".
*
* A response to a ping is no guarantee that the host
* is running NFS, has a mount daemon, or exports
* the required filesystem. If the subsequent
* mount attempt fails then the host will be marked
* "ignore" and the host list will be re-pinged
* (sans the bad host). This process continues
* until a successful mount is achieved or until
* there are no hosts left to try.
*/
enum clnt_stat
nfs_cast(struct mapfs *mfs_in, struct mapfs **mfs_out, int timeout)
{
enum clnt_stat stat;
AUTH *sys_auth = authsys_create_default();
XDR xdr_stream;
register XDR *xdrs = &xdr_stream;
int outlen;
int if_inx;
int tsec;
int flag;
int sent, addr_cnt, rcvd, if_cnt;
fd_set readfds, mask;
register ulong_t xid; /* xid - unique per addr */
register int i;
struct rpc_msg msg;
struct timeval t, rcv_timeout;
char outbuf[UDPMSGSIZE], inbuf[UDPMSGSIZE];
struct t_unitdata t_udata, t_rdata;
struct nd_hostserv hs;
struct nd_addrlist *retaddrs;
struct transp *tr_head;
struct transp *trans, *prev_trans;
struct addrs *a, *prev_addr;
struct tstamps *ts, *prev_ts;
NCONF_HANDLE *nc = NULL;
struct netconfig *nconf;
struct rlimit rl;
int dtbsize;
struct mapfs *mfs;
/*
* For each connectionless transport get a list of
* host addresses. Any single host may have
* addresses on several transports.
*/
addr_cnt = sent = rcvd = 0;
tr_head = NULL;
FD_ZERO(&mask);
/*
* Set the default select size to be the maximum FD_SETSIZE, unless
* the current rlimit is lower.
*/
dtbsize = FD_SETSIZE;
if (getrlimit(RLIMIT_NOFILE, &rl) == 0) {
if (rl.rlim_cur < FD_SETSIZE)
dtbsize = rl.rlim_cur;
}
prev_trans = NULL;
prev_addr = NULL;
prev_ts = NULL;
for (mfs = mfs_in; mfs; mfs = mfs->mfs_next) {
if (trace > 2)
trace_prt(1, "nfs_cast: host=%s\n", mfs->mfs_host);
nc = setnetconfig();
if (nc == NULL) {
stat = RPC_CANTSEND;
goto done_broad;
}
while (nconf = getnetconfig(nc)) {
if (!(nconf->nc_flag & NC_VISIBLE) ||
nconf->nc_semantics != NC_TPI_CLTS ||
(strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0))
continue;
trans = (struct transp *)malloc(sizeof (*trans));
if (trans == NULL) {
syslog(LOG_ERR, "no memory");
stat = RPC_CANTSEND;
goto done_broad;
}
(void) memset(trans, 0, sizeof (*trans));
if (tr_head == NULL)
tr_head = trans;
else
prev_trans->tr_next = trans;
prev_trans = trans;
trans->tr_fd = t_open(nconf->nc_device, O_RDWR, NULL);
if (trans->tr_fd < 0) {
syslog(LOG_ERR, "nfscast: t_open: %s:%m",
nconf->nc_device);
stat = RPC_CANTSEND;
goto done_broad;
}
if (t_bind(trans->tr_fd, (struct t_bind *)NULL,
(struct t_bind *)NULL) < 0) {
syslog(LOG_ERR, "nfscast: t_bind: %m");
stat = RPC_CANTSEND;
goto done_broad;
}
trans->tr_taddr =
/* LINTED pointer alignment */
(struct t_bind *)t_alloc(trans->tr_fd, T_BIND, T_ADDR);
if (trans->tr_taddr == (struct t_bind *)NULL) {
syslog(LOG_ERR, "nfscast: t_alloc: %m");
stat = RPC_SYSTEMERROR;
goto done_broad;
}
trans->tr_device = nconf->nc_device;
FD_SET(trans->tr_fd, &mask);
if_inx = 0;
hs.h_host = mfs->mfs_host;
hs.h_serv = "rpcbind";
if (netdir_getbyname(nconf, &hs, &retaddrs) == ND_OK) {
/*
* If mfs->ignore is previously set for
* this map, clear it. Because a host can
* have either v6 or v4 address
*/
if (mfs->mfs_ignore == 1)
mfs->mfs_ignore = 0;
a = (struct addrs *)malloc(sizeof (*a));
if (a == NULL) {
syslog(LOG_ERR, "no memory");
stat = RPC_CANTSEND;
goto done_broad;
}
(void) memset(a, 0, sizeof (*a));
if (trans->tr_addrs == NULL)
trans->tr_addrs = a;
else
prev_addr->addr_next = a;
prev_addr = a;
a->addr_if_tstamps = NULL;
a->addr_mfs = mfs;
a->addr_addrs = retaddrs;
if_cnt = retaddrs->n_cnt;
while (if_cnt--) {
ts = (struct tstamps *)
malloc(sizeof (*ts));
if (ts == NULL) {
syslog(LOG_ERR, "no memory");
stat = RPC_CANTSEND;
goto done_broad;
}
(void) memset(ts, 0, sizeof (*ts));
ts->ts_penalty = mfs->mfs_penalty;
if (a->addr_if_tstamps == NULL)
a->addr_if_tstamps = ts;
else
prev_ts->ts_next = ts;
prev_ts = ts;
ts->ts_inx = if_inx++;
addr_cnt++;
}
break;
} else {
mfs->mfs_ignore = 1;
if (verbose)
syslog(LOG_ERR,
"%s:%s address not known",
mfs->mfs_host,
strcmp(nconf->nc_proto, NC_INET)?"IPv6":"IPv4");
}
} /* while */
endnetconfig(nc);
nc = NULL;
} /* for */
if (addr_cnt == 0) {
syslog(LOG_ERR, "nfscast: couldn't find addresses");
stat = RPC_CANTSEND;
goto done_broad;
}
(void) gettimeofday(&t, (struct timezone *)0);
xid = (getpid() ^ t.tv_sec ^ t.tv_usec) & ~0xFF;
t.tv_usec = 0;
/* serialize the RPC header */
msg.rm_direction = CALL;
msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
msg.rm_call.cb_prog = RPCBPROG;
/*
* we can not use RPCBVERS here since it doesn't exist in 4.X,
* the fix to bug 1139883 has made the 4.X portmapper silent to
* version mismatches. This causes the RPC call to the remote
* portmapper to simply be ignored if it's not Version 2.
*/
msg.rm_call.cb_vers = PMAPVERS;
msg.rm_call.cb_proc = NULLPROC;
if (sys_auth == (AUTH *)NULL) {
stat = RPC_SYSTEMERROR;
goto done_broad;
}
msg.rm_call.cb_cred = sys_auth->ah_cred;
msg.rm_call.cb_verf = sys_auth->ah_verf;
xdrmem_create(xdrs, outbuf, sizeof (outbuf), XDR_ENCODE);
if (! xdr_callmsg(xdrs, &msg)) {
stat = RPC_CANTENCODEARGS;
goto done_broad;
}
outlen = (int)xdr_getpos(xdrs);
xdr_destroy(xdrs);
t_udata.opt.len = 0;
t_udata.udata.buf = outbuf;
t_udata.udata.len = outlen;
/*
* Basic loop: send packet to all hosts and wait for response(s).
* The response timeout grows larger per iteration.
* A unique xid is assigned to each address in order to
* correctly match the replies.
*/
for (tsec = 4; timeout > 0; tsec *= 2) {
timeout -= tsec;
if (timeout <= 0)
tsec += timeout;
rcv_timeout.tv_sec = tsec;
rcv_timeout.tv_usec = 0;
sent = 0;
for (trans = tr_head; trans; trans = trans->tr_next) {
for (a = trans->tr_addrs; a; a = a->addr_next) {
struct netbuf *if_netbuf =
a->addr_addrs->n_addrs;
ts = a->addr_if_tstamps;
if_cnt = a->addr_addrs->n_cnt;
while (if_cnt--) {
/*
* xid is the first thing in
* preserialized buffer
*/
/* LINTED pointer alignment */
*((ulong_t *)outbuf) =
htonl(xid + ts->ts_inx);
(void) gettimeofday(&(ts->ts_timeval),
(struct timezone *)0);
/*
* Check if already received
* from a previous iteration.
*/
if (ts->ts_rcvd) {
sent++;
ts = ts->ts_next;
continue;
}
t_udata.addr = *if_netbuf++;
if (t_sndudata(trans->tr_fd,
&t_udata) == 0) {
sent++;
}
ts = ts->ts_next;
}
}
}
if (sent == 0) { /* no packets sent ? */
stat = RPC_CANTSEND;
goto done_broad;
}
/*
* Have sent all the packets. Now collect the responses...
*/
rcvd = 0;
recv_again:
msg.acpted_rply.ar_verf = _null_auth;
msg.acpted_rply.ar_results.proc = xdr_void;
readfds = mask;
switch (select(dtbsize, &readfds,
(fd_set *)NULL, (fd_set *)NULL, &rcv_timeout)) {
case 0: /* Timed out */
/*
* If we got at least one response in the
* last interval, then don't wait for any
* more. In theory we should wait for
* the max weighting (penalty) value so
* that a very slow server has a chance to
* respond but this could take a long time
* if the admin has set a high weighting
* value.
*/
if (rcvd > 0)
goto done_broad;
stat = RPC_TIMEDOUT;
continue;
case -1: /* some kind of error */
if (errno == EINTR)
goto recv_again;
syslog(LOG_ERR, "nfscast: select: %m");
if (rcvd == 0)
stat = RPC_CANTRECV;
goto done_broad;
} /* end of select results switch */
for (trans = tr_head; trans; trans = trans->tr_next) {
if (FD_ISSET(trans->tr_fd, &readfds))
break;
}
if (trans == NULL)
goto recv_again;
try_again:
t_rdata.addr = trans->tr_taddr->addr;
t_rdata.udata.buf = inbuf;
t_rdata.udata.maxlen = sizeof (inbuf);
t_rdata.udata.len = 0;
t_rdata.opt.len = 0;
if (t_rcvudata(trans->tr_fd, &t_rdata, &flag) < 0) {
if (errno == EINTR)
goto try_again;
syslog(LOG_ERR, "nfscast: t_rcvudata: %s:%m",
trans->tr_device);
stat = RPC_CANTRECV;
continue;
}
if (t_rdata.udata.len < sizeof (ulong_t))
goto recv_again;
if (flag & T_MORE) {
syslog(LOG_ERR,
"nfscast: t_rcvudata: %s: buffer overflow",
trans->tr_device);
goto recv_again;
}
/*
* see if reply transaction id matches sent id.
* If so, decode the results.
* Note: received addr is ignored, it could be
* different from the send addr if the host has
* more than one addr.
*/
xdrmem_create(xdrs, inbuf, (uint_t)t_rdata.udata.len,
XDR_DECODE);
if (xdr_replymsg(xdrs, &msg)) {
if (msg.rm_reply.rp_stat == MSG_ACCEPTED &&
(msg.rm_xid & ~0xFF) == xid) {
struct addrs *curr_addr;
i = msg.rm_xid & 0xFF;
for (curr_addr = trans->tr_addrs; curr_addr;
curr_addr = curr_addr->addr_next) {
for (ts = curr_addr->addr_if_tstamps; ts;
ts = ts->ts_next)
if (ts->ts_inx == i && !ts->ts_rcvd) {
ts->ts_rcvd = 1;
calc_resp_time(&ts->ts_timeval);
stat = RPC_SUCCESS;
rcvd++;
break;
}
}
} /* otherwise, we just ignore the errors ... */
}
xdrs->x_op = XDR_FREE;
msg.acpted_rply.ar_results.proc = xdr_void;
(void) xdr_replymsg(xdrs, &msg);
XDR_DESTROY(xdrs);
if (rcvd == sent)
goto done_broad;
else
goto recv_again;
}
if (!rcvd)
stat = RPC_TIMEDOUT;
done_broad:
if (rcvd) {
*mfs_out = sort_responses(tr_head);
stat = RPC_SUCCESS;
}
if (nc)
endnetconfig(nc);
free_transports(tr_head);
AUTH_DESTROY(sys_auth);
return (stat);
}
/*
* Go through all the responses and sort fastest to slowest.
* Note that any penalty is added to the response time - so the
* fastest response isn't necessarily the one that arrived first.
*/
static struct mapfs *
sort_responses(trans)
struct transp *trans;
{
struct transp *t;
struct addrs *a;
struct tstamps *ti;
int i, size = 0, allocsize = 10;
struct mapfs *p, *mfs_head = NULL, *mfs_tail = NULL;
struct sm *buffer;
buffer = (struct sm *)malloc(allocsize * sizeof (struct sm));
if (!buffer) {
syslog(LOG_ERR, "sort_responses: malloc error.\n");
return (NULL);
}
for (t = trans; t; t = t->tr_next) {
for (a = t->tr_addrs; a; a = a->addr_next) {
for (ti = a->addr_if_tstamps;
ti; ti = ti->ts_next) {
if (!ti->ts_rcvd)
continue;
ti->ts_timeval.tv_usec +=
(ti->ts_penalty * PENALTY_WEIGHT);
if (ti->ts_timeval.tv_usec >= 1000000) {
ti->ts_timeval.tv_sec +=
(ti->ts_timeval.tv_usec / 1000000);
ti->ts_timeval.tv_usec =
(ti->ts_timeval.tv_usec % 1000000);
}
if (size >= allocsize) {
allocsize += 10;
buffer = (struct sm *)realloc(buffer,
allocsize * sizeof (struct sm));
if (!buffer) {
syslog(LOG_ERR,
"sort_responses: malloc error.\n");
return (NULL);
}
}
buffer[size].timeval = ti->ts_timeval;
buffer[size].mfs = a->addr_mfs;
size++;
}
}
}
#ifdef DEBUG
if (trace > 3) {
trace_prt(1, " sort_responses: before host sort:\n");
for (i = 0; i < size; i++)
trace_prt(1, " %s %d.%d\n", buffer[i].mfs->mfs_host,
buffer[i].timeval.tv_sec, buffer[i].timeval.tv_usec);
trace_prt(0, "\n");
}
#endif
qsort((void *)buffer, size, sizeof (struct sm), host_sm);
/*
* Cope with multiply listed hosts by choosing first time
*/
for (i = 1; i < size; i++) {
#ifdef DEBUG
if (trace > 3) {
trace_prt(1, " sort_responses: comparing %s and %s\n",
buffer[i-1].mfs->mfs_host,
buffer[i].mfs->mfs_host);
}
#endif
if (strcmp(buffer[i-1].mfs->mfs_host,
buffer[i].mfs->mfs_host) == 0)
memcpy(&buffer[i].timeval, &buffer[i-1].timeval,
sizeof (struct timeval));
}
if (trace > 3)
trace_prt(0, "\n");
#ifdef DEBUG
if (trace > 3) {
trace_prt(1, " sort_responses: before time sort:\n");
for (i = 0; i < size; i++)
trace_prt(1, " %s %d.%d\n", buffer[i].mfs->mfs_host,
buffer[i].timeval.tv_sec, buffer[i].timeval.tv_usec);
trace_prt(0, "\n");
}
#endif
qsort((void *)buffer, size, sizeof (struct sm), time_sm);
#ifdef DEBUG
if (trace > 3) {
trace_prt(1, " sort_responses: after sort:\n");
for (i = 0; i < size; i++)
trace_prt(1, " %s %d.%d\n", buffer[i].mfs->mfs_host,
buffer[i].timeval.tv_sec, buffer[i].timeval.tv_usec);
trace_prt(0, "\n");
}
#endif
for (i = 0; i < size; i++) {
#ifdef DEBUG
if (trace > 3) {
trace_prt(1, " sort_responses: adding %s\n",
buffer[i].mfs->mfs_host);
}
#endif
p = add_mfs(buffer[i].mfs, 0, &mfs_head, &mfs_tail);
if (!p)
return (NULL);
}
free(buffer);
return (mfs_head);
}
/*
* Comparison routines called by qsort(3).
*/
static int host_sm(const void *a, const void *b)
{
return (strcmp(((struct sm *)a)->mfs->mfs_host,
((struct sm *)b)->mfs->mfs_host));
}
static int time_sm(const void *a, const void *b)
{
if (timercmp(&(((struct sm *)a)->timeval),
&(((struct sm *)b)->timeval), < /* cstyle */))
return (-1);
else if (timercmp(&(((struct sm *)a)->timeval),
&(((struct sm *)b)->timeval), > /* cstyle */))
return (1);
else
return (0);
}
/*
* Given send_time which is the time a request
* was transmitted to a server, subtract it
* from the time "now" thereby converting it
* to an elapsed time.
*/
static void
calc_resp_time(send_time)
struct timeval *send_time;
{
struct timeval time_now;
(void) gettimeofday(&time_now, (struct timezone *)0);
if (time_now.tv_usec < send_time->tv_usec) {
time_now.tv_sec--;
time_now.tv_usec += 1000000;
}
send_time->tv_sec = time_now.tv_sec - send_time->tv_sec;
send_time->tv_usec = time_now.tv_usec - send_time->tv_usec;
}
static void
free_transports(trans)
struct transp *trans;
{
struct transp *t, *tmpt = NULL;
struct addrs *a, *tmpa = NULL;
struct tstamps *ts, *tmpts = NULL;
for (t = trans; t; t = tmpt) {
if (t->tr_taddr)
(void) t_free((char *)t->tr_taddr, T_BIND);
if (t->tr_fd > 0)
(void) t_close(t->tr_fd);
for (a = t->tr_addrs; a; a = tmpa) {
for (ts = a->addr_if_tstamps; ts; ts = tmpts) {
tmpts = ts->ts_next;
free(ts);
}
(void) netdir_free((char *)a->addr_addrs, ND_ADDRLIST);
tmpa = a->addr_next;
free(a);
}
tmpt = t->tr_next;
free(t);
}
}