freebsd-src/usr.sbin/ypbind/ypbind.c
Pedro F. Giffuni 1de7b4b805 various: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:37:16 +00:00

1025 lines
25 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1992/3 Theo de Raadt <deraadt@fsa.ca>
* All rights reserved.
*
* 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.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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/param.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/signal.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <sys/fcntl.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <rpc/rpc.h>
#include <rpc/xdr.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <rpc/pmap_rmt.h>
#include <rpc/rpc_com.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>
#include "yp_ping.h"
#ifndef BINDINGDIR
#define BINDINGDIR "/var/yp/binding"
#endif
#ifndef YPBINDLOCK
#define YPBINDLOCK "/var/run/ypbind.lock"
#endif
struct _dom_binding {
struct _dom_binding *dom_pnext;
char dom_domain[YPMAXDOMAIN + 1];
struct sockaddr_in dom_server_addr;
long int dom_vers;
int dom_lockfd;
int dom_alive;
int dom_broadcast_pid;
int dom_pipe_fds[2];
int dom_default;
};
#define READFD ypdb->dom_pipe_fds[0]
#define WRITEFD ypdb->dom_pipe_fds[1]
#define BROADFD broad_domain->dom_pipe_fds[1]
extern bool_t xdr_domainname(), xdr_ypbind_resp();
extern bool_t xdr_ypreq_key(), xdr_ypresp_val();
extern bool_t xdr_ypbind_setdom();
void checkwork(void);
void *ypbindproc_null_2_yp(SVCXPRT *, void *, CLIENT *);
void *ypbindproc_setdom_2_yp(SVCXPRT *, struct ypbind_setdom *, CLIENT *);
void rpc_received(char *, struct sockaddr_in *, int);
void broadcast(struct _dom_binding *);
int ping(struct _dom_binding *);
int tell_parent(char *, struct sockaddr_in *);
void handle_children(struct _dom_binding *);
void reaper(int);
void terminate(int);
void yp_restricted_mode(char *);
int verify(struct in_addr);
static char *domain_name;
static struct _dom_binding *ypbindlist;
static struct _dom_binding *broad_domain;
#define YPSET_NO 0
#define YPSET_LOCAL 1
#define YPSET_ALL 2
static int ypsetmode = YPSET_NO;
static int ypsecuremode = 0;
static int ppid;
#define NOT_RESPONDING_HYSTERESIS 10
static int not_responding_count = 0;
/*
* Special restricted mode variables: when in restricted mode, only the
* specified restricted_domain will be bound, and only the servers listed
* in restricted_addrs will be used for binding.
*/
#define RESTRICTED_SERVERS 10
static int yp_restricted = 0;
static int yp_manycast = 0;
static struct in_addr restricted_addrs[RESTRICTED_SERVERS];
/* No more than MAX_CHILDREN child broadcasters at a time. */
#ifndef MAX_CHILDREN
#define MAX_CHILDREN 5
#endif
/* No more than MAX_DOMAINS simultaneous domains */
#ifndef MAX_DOMAINS
#define MAX_DOMAINS 200
#endif
/* RPC timeout value */
#ifndef FAIL_THRESHOLD
#define FAIL_THRESHOLD 20
#endif
/* Number of times to fish for a response froma particular set of hosts */
#ifndef MAX_RETRIES
#define MAX_RETRIES 30
#endif
static int retries = 0;
static int children = 0;
static int domains = 0;
static int yplockfd;
static fd_set fdsr;
static SVCXPRT *udptransp, *tcptransp;
void *
ypbindproc_null_2_yp(SVCXPRT *transp, void *argp, CLIENT *clnt)
{
static char res;
bzero(&res, sizeof(res));
return &res;
}
static struct ypbind_resp *
ypbindproc_domain_2_yp(SVCXPRT *transp, domainname *argp, CLIENT *clnt)
{
static struct ypbind_resp res;
struct _dom_binding *ypdb;
char path[MAXPATHLEN];
bzero(&res, sizeof res);
res.ypbind_status = YPBIND_FAIL_VAL;
res.ypbind_resp_u.ypbind_error = YPBIND_ERR_NOSERV;
if (strchr(*argp, '/')) {
syslog(LOG_WARNING, "Domain name '%s' has embedded slash -- \
rejecting.", *argp);
return(&res);
}
for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) {
if (strcmp(ypdb->dom_domain, *argp) == 0)
break;
}
if (ypdb == NULL) {
if (yp_restricted) {
syslog(LOG_NOTICE, "Running in restricted mode -- request to bind domain \"%s\" rejected.\n", *argp);
return (&res);
}
if (domains >= MAX_DOMAINS) {
syslog(LOG_WARNING, "domain limit (%d) exceeded",
MAX_DOMAINS);
res.ypbind_resp_u.ypbind_error = YPBIND_ERR_RESC;
return (&res);
}
if (strlen(*argp) > YPMAXDOMAIN) {
syslog(LOG_WARNING, "domain %s too long", *argp);
res.ypbind_resp_u.ypbind_error = YPBIND_ERR_RESC;
return (&res);
}
ypdb = malloc(sizeof *ypdb);
if (ypdb == NULL) {
syslog(LOG_WARNING, "malloc: %m");
res.ypbind_resp_u.ypbind_error = YPBIND_ERR_RESC;
return (&res);
}
bzero(ypdb, sizeof *ypdb);
strlcpy(ypdb->dom_domain, *argp, sizeof ypdb->dom_domain);
ypdb->dom_vers = YPVERS;
ypdb->dom_alive = 0;
ypdb->dom_default = 0;
ypdb->dom_lockfd = -1;
sprintf(path, "%s/%s.%ld", BINDINGDIR,
ypdb->dom_domain, ypdb->dom_vers);
unlink(path);
ypdb->dom_pnext = ypbindlist;
ypbindlist = ypdb;
domains++;
}
if (ping(ypdb)) {
return (&res);
}
res.ypbind_status = YPBIND_SUCC_VAL;
res.ypbind_resp_u.ypbind_error = 0; /* Success */
memcpy(&res.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_addr,
&ypdb->dom_server_addr.sin_addr.s_addr, sizeof(u_int32_t));
memcpy(&res.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_port,
&ypdb->dom_server_addr.sin_port, sizeof(u_short));
/*printf("domain %s at %s/%d\n", ypdb->dom_domain,
inet_ntoa(ypdb->dom_server_addr.sin_addr),
ntohs(ypdb->dom_server_addr.sin_port));*/
return (&res);
}
void *
ypbindproc_setdom_2_yp(SVCXPRT *transp, ypbind_setdom *argp, CLIENT *clnt)
{
struct sockaddr_in *fromsin, bindsin;
static char *result = NULL;
if (strchr(argp->ypsetdom_domain, '/')) {
syslog(LOG_WARNING, "Domain name '%s' has embedded slash -- \
rejecting.", argp->ypsetdom_domain);
return(NULL);
}
fromsin = svc_getcaller(transp);
switch (ypsetmode) {
case YPSET_LOCAL:
if (fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) {
svcerr_noprog(transp);
return(NULL);
}
break;
case YPSET_ALL:
break;
case YPSET_NO:
default:
svcerr_noprog(transp);
return(NULL);
}
if (ntohs(fromsin->sin_port) >= IPPORT_RESERVED) {
svcerr_noprog(transp);
return(NULL);
}
if (argp->ypsetdom_vers != YPVERS) {
svcerr_noprog(transp);
return(NULL);
}
bzero(&bindsin, sizeof bindsin);
bindsin.sin_family = AF_INET;
memcpy(&bindsin.sin_addr.s_addr,
&argp->ypsetdom_binding.ypbind_binding_addr,
sizeof(u_int32_t));
memcpy(&bindsin.sin_port,
&argp->ypsetdom_binding.ypbind_binding_port,
sizeof(u_short));
rpc_received(argp->ypsetdom_domain, &bindsin, 1);
return((void *) &result);
}
void
ypbindprog_2(struct svc_req *rqstp, register SVCXPRT *transp)
{
union {
domainname ypbindproc_domain_2_arg;
struct ypbind_setdom ypbindproc_setdom_2_arg;
} argument;
struct authunix_parms *creds;
char *result;
bool_t (*xdr_argument)(), (*xdr_result)();
char *(*local)();
switch (rqstp->rq_proc) {
case YPBINDPROC_NULL:
xdr_argument = xdr_void;
xdr_result = xdr_void;
local = (char *(*)()) ypbindproc_null_2_yp;
break;
case YPBINDPROC_DOMAIN:
xdr_argument = xdr_domainname;
xdr_result = xdr_ypbind_resp;
local = (char *(*)()) ypbindproc_domain_2_yp;
break;
case YPBINDPROC_SETDOM:
switch (rqstp->rq_cred.oa_flavor) {
case AUTH_UNIX:
creds = (struct authunix_parms *)rqstp->rq_clntcred;
if (creds->aup_uid != 0) {
svcerr_auth(transp, AUTH_BADCRED);
return;
}
break;
default:
svcerr_auth(transp, AUTH_TOOWEAK);
return;
}
xdr_argument = xdr_ypbind_setdom;
xdr_result = xdr_void;
local = (char *(*)()) ypbindproc_setdom_2_yp;
break;
default:
svcerr_noproc(transp);
return;
}
bzero(&argument, sizeof(argument));
if (!svc_getargs(transp, (xdrproc_t)xdr_argument, &argument)) {
svcerr_decode(transp);
return;
}
result = (*local)(transp, &argument, rqstp);
if (result != NULL &&
!svc_sendreply(transp, (xdrproc_t)xdr_result, result)) {
svcerr_systemerr(transp);
}
return;
}
/* Jack the reaper */
void
reaper(int sig)
{
int st;
while (wait3(&st, WNOHANG, NULL) > 0)
children--;
}
void
terminate(int sig)
{
struct _dom_binding *ypdb;
char path[MAXPATHLEN];
if (ppid != getpid())
exit(0);
for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) {
close(ypdb->dom_lockfd);
if (ypdb->dom_broadcast_pid)
kill(ypdb->dom_broadcast_pid, SIGINT);
sprintf(path, "%s/%s.%ld", BINDINGDIR,
ypdb->dom_domain, ypdb->dom_vers);
unlink(path);
}
close(yplockfd);
unlink(YPBINDLOCK);
pmap_unset(YPBINDPROG, YPBINDVERS);
exit(0);
}
int
main(int argc, char *argv[])
{
struct timeval tv;
int i;
DIR *dird;
struct dirent *dirp;
struct _dom_binding *ypdb, *next;
/* Check that another ypbind isn't already running. */
if ((yplockfd = (open(YPBINDLOCK, O_RDONLY|O_CREAT, 0444))) == -1)
err(1, "%s", YPBINDLOCK);
if (flock(yplockfd, LOCK_EX|LOCK_NB) == -1 && errno == EWOULDBLOCK)
errx(1, "another ypbind is already running. Aborting");
/* XXX domainname will be overridden if we use restricted mode */
yp_get_default_domain(&domain_name);
if (domain_name[0] == '\0')
errx(1, "domainname not set. Aborting");
for (i = 1; i<argc; i++) {
if (strcmp("-ypset", argv[i]) == 0)
ypsetmode = YPSET_ALL;
else if (strcmp("-ypsetme", argv[i]) == 0)
ypsetmode = YPSET_LOCAL;
else if (strcmp("-s", argv[i]) == 0)
ypsecuremode++;
else if (strcmp("-S", argv[i]) == 0 && argc > i)
yp_restricted_mode(argv[++i]);
else if (strcmp("-m", argv[i]) == 0)
yp_manycast++;
else
errx(1, "unknown option: %s", argv[i]);
}
if (strlen(domain_name) > YPMAXDOMAIN)
warnx("truncating domain name %s", domain_name);
/* blow away everything in BINDINGDIR (if it exists) */
if ((dird = opendir(BINDINGDIR)) != NULL) {
char path[MAXPATHLEN];
while ((dirp = readdir(dird)) != NULL)
if (strcmp(dirp->d_name, ".") &&
strcmp(dirp->d_name, "..")) {
sprintf(path,"%s/%s",BINDINGDIR,dirp->d_name);
unlink(path);
}
closedir(dird);
}
#ifdef DAEMON
if (daemon(0,0))
err(1, "fork");
#endif
pmap_unset(YPBINDPROG, YPBINDVERS);
udptransp = svcudp_create(RPC_ANYSOCK);
if (udptransp == NULL)
errx(1, "cannot create udp service");
if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
IPPROTO_UDP))
errx(1, "unable to register (YPBINDPROG, YPBINDVERS, udp)");
tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0);
if (tcptransp == NULL)
errx(1, "cannot create tcp service");
if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
IPPROTO_TCP))
errx(1, "unable to register (YPBINDPROG, YPBINDVERS, tcp)");
/* build initial domain binding, make it "unsuccessful" */
ypbindlist = malloc(sizeof *ypbindlist);
if (ypbindlist == NULL)
errx(1, "malloc");
bzero(ypbindlist, sizeof *ypbindlist);
strlcpy(ypbindlist->dom_domain, domain_name, sizeof ypbindlist->dom_domain);
ypbindlist->dom_vers = YPVERS;
ypbindlist->dom_alive = 0;
ypbindlist->dom_lockfd = -1;
ypbindlist->dom_default = 1;
domains++;
signal(SIGCHLD, reaper);
signal(SIGTERM, terminate);
ppid = getpid(); /* Remember who we are. */
openlog(argv[0], LOG_PID, LOG_DAEMON);
if (madvise(NULL, 0, MADV_PROTECT) != 0)
syslog(LOG_WARNING, "madvise(): %m");
/* Kick off the default domain */
broadcast(ypbindlist);
while (1) {
fdsr = svc_fdset;
tv.tv_sec = 60;
tv.tv_usec = 0;
switch (select(_rpc_dtablesize(), &fdsr, NULL, NULL, &tv)) {
case 0:
checkwork();
break;
case -1:
if (errno != EINTR)
syslog(LOG_WARNING, "select: %m");
break;
default:
for (ypdb = ypbindlist; ypdb; ypdb = next) {
next = ypdb->dom_pnext;
if (READFD > 0 && FD_ISSET(READFD, &fdsr)) {
handle_children(ypdb);
if (children == (MAX_CHILDREN - 1))
checkwork();
}
}
svc_getreqset(&fdsr);
break;
}
}
/* NOTREACHED */
exit(1);
}
void
checkwork(void)
{
struct _dom_binding *ypdb;
for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext)
ping(ypdb);
}
/* The clnt_broadcast() callback mechanism sucks. */
/*
* Receive results from broadcaster. Don't worry about passing
* bogus info to rpc_received() -- it can handle it. Note that we
* must be sure to invalidate the dom_pipe_fds descriptors here:
* since descriptors can be re-used, we have to make sure we
* don't mistake one of the RPC descriptors for one of the pipes.
* What's weird is that forgetting to invalidate the pipe descriptors
* doesn't always result in an error (otherwise I would have caught
* the mistake much sooner), even though logically it should.
*/
void
handle_children(struct _dom_binding *ypdb)
{
char buf[YPMAXDOMAIN + 1];
struct sockaddr_in addr;
int d = 0, a = 0;
struct _dom_binding *y, *prev = NULL;
char path[MAXPATHLEN];
if ((d = read(READFD, &buf, sizeof(buf))) <= 0)
syslog(LOG_WARNING, "could not read from child: %m");
if ((a = read(READFD, &addr, sizeof(struct sockaddr_in))) < 0)
syslog(LOG_WARNING, "could not read from child: %m");
close(READFD);
FD_CLR(READFD, &fdsr);
FD_CLR(READFD, &svc_fdset);
READFD = WRITEFD = -1;
if (d > 0 && a > 0)
rpc_received(buf, &addr, 0);
else {
for (y = ypbindlist; y; y = y->dom_pnext) {
if (y == ypdb)
break;
prev = y;
}
switch (ypdb->dom_default) {
case 0:
if (prev == NULL)
ypbindlist = y->dom_pnext;
else
prev->dom_pnext = y->dom_pnext;
sprintf(path, "%s/%s.%ld", BINDINGDIR,
ypdb->dom_domain, YPVERS);
close(ypdb->dom_lockfd);
unlink(path);
free(ypdb);
domains--;
return;
case 1:
ypdb->dom_broadcast_pid = 0;
ypdb->dom_alive = 0;
broadcast(ypdb);
return;
default:
break;
}
}
return;
}
/*
* Send our dying words back to our parent before we perish.
*/
int
tell_parent(char *dom, struct sockaddr_in *addr)
{
char buf[YPMAXDOMAIN + 1];
struct timeval timeout;
fd_set fds;
timeout.tv_sec = 5;
timeout.tv_usec = 0;
sprintf(buf, "%s", broad_domain->dom_domain);
if (write(BROADFD, &buf, sizeof(buf)) < 0)
return(1);
/*
* Stay in sync with parent: wait for it to read our first
* message before sending the second.
*/
FD_ZERO(&fds);
FD_SET(BROADFD, &fds);
if (select(FD_SETSIZE, NULL, &fds, NULL, &timeout) == -1)
return(1);
if (FD_ISSET(BROADFD, &fds)) {
if (write(BROADFD, addr, sizeof(struct sockaddr_in)) < 0)
return(1);
} else {
return(1);
}
close(BROADFD);
return (0);
}
static bool_t
broadcast_result(bool_t *out, struct sockaddr_in *addr)
{
if (retries >= MAX_RETRIES) {
bzero(addr, sizeof(struct sockaddr_in));
if (tell_parent(broad_domain->dom_domain, addr))
syslog(LOG_WARNING, "lost connection to parent");
return (TRUE);
}
if (yp_restricted && verify(addr->sin_addr)) {
retries++;
syslog(LOG_NOTICE, "NIS server at %s not in restricted mode access list -- rejecting.\n",inet_ntoa(addr->sin_addr));
return (FALSE);
} else {
if (tell_parent(broad_domain->dom_domain, addr))
syslog(LOG_WARNING, "lost connection to parent");
return (TRUE);
}
}
/*
* The right way to send RPC broadcasts.
* Use the clnt_broadcast() RPC service. Unfortunately, clnt_broadcast()
* blocks while waiting for replies, so we have to fork off separate
* broadcaster processes that do the waiting and then transmit their
* results back to the parent for processing. We also have to remember
* to save the name of the domain we're trying to bind in a global
* variable since clnt_broadcast() provides no way to pass things to
* the 'eachresult' callback function.
*/
void
broadcast(struct _dom_binding *ypdb)
{
bool_t out = FALSE;
enum clnt_stat stat;
if (children >= MAX_CHILDREN || ypdb->dom_broadcast_pid)
return;
if (pipe(ypdb->dom_pipe_fds) < 0) {
syslog(LOG_WARNING, "pipe: %m");
return;
}
if (ypdb->dom_vers == -1 && (long)ypdb->dom_server_addr.sin_addr.s_addr) {
if (not_responding_count++ >= NOT_RESPONDING_HYSTERESIS) {
not_responding_count = NOT_RESPONDING_HYSTERESIS;
syslog(LOG_WARNING, "NIS server [%s] for domain \"%s\" not responding",
inet_ntoa(ypdb->dom_server_addr.sin_addr), ypdb->dom_domain);
}
}
broad_domain = ypdb;
flock(ypdb->dom_lockfd, LOCK_UN);
switch ((ypdb->dom_broadcast_pid = fork())) {
case 0:
close(READFD);
signal(SIGCHLD, SIG_DFL);
signal(SIGTERM, SIG_DFL);
break;
case -1:
syslog(LOG_WARNING, "fork: %m");
close(READFD);
close(WRITEFD);
return;
default:
close(WRITEFD);
FD_SET(READFD, &svc_fdset);
children++;
return;
}
/* Release all locks before doing anything else. */
while (ypbindlist) {
close(ypbindlist->dom_lockfd);
ypbindlist = ypbindlist->dom_pnext;
}
close(yplockfd);
/*
* Special 'many-cast' behavior. If we're in restricted mode,
* we have a list of possible server addresses to try. What
* we can do is transmit to each ypserv's YPPROC_DOMAIN_NONACK
* procedure and time the replies. Whoever replies fastest
* gets to be our server. Note that this is not a broadcast
* operation: we transmit uni-cast datagrams only.
*/
if (yp_restricted && yp_manycast) {
short port;
int i;
struct sockaddr_in sin;
i = __yp_ping(restricted_addrs, yp_restricted,
ypdb->dom_domain, &port);
if (i == -1) {
bzero(&ypdb->dom_server_addr,
sizeof(struct sockaddr_in));
if (tell_parent(ypdb->dom_domain,
&ypdb->dom_server_addr))
syslog(LOG_WARNING, "lost connection to parent");
} else {
bzero(&sin, sizeof(struct sockaddr_in));
bcopy(&restricted_addrs[i],
&sin.sin_addr, sizeof(struct in_addr));
sin.sin_family = AF_INET;
sin.sin_port = port;
if (tell_parent(broad_domain->dom_domain, &sin))
syslog(LOG_WARNING,
"lost connection to parent");
}
_exit(0);
}
retries = 0;
{
char *ptr;
ptr = ypdb->dom_domain;
stat = clnt_broadcast(YPPROG, YPVERS, YPPROC_DOMAIN_NONACK,
(xdrproc_t)xdr_domainname, &ptr,
(xdrproc_t)xdr_bool, &out,
(resultproc_t)broadcast_result);
}
if (stat != RPC_SUCCESS) {
bzero(&ypdb->dom_server_addr,
sizeof(struct sockaddr_in));
if (tell_parent(ypdb->dom_domain, &ypdb->dom_server_addr))
syslog(LOG_WARNING, "lost connection to parent");
}
_exit(0);
}
/*
* The right way to check if a server is alive.
* Attempt to get a client handle pointing to the server and send a
* YPPROC_DOMAIN. If we can't get a handle or we get a reply of FALSE,
* we invalidate this binding entry and send out a broadcast to try to
* establish a new binding. Note that we treat non-default domains
* specially: once bound, we keep tabs on our server, but if it
* goes away and fails to respond after one round of broadcasting, we
* abandon it until a client specifically references it again. We make
* every effort to keep our default domain bound, however, since we
* need it to keep the system on its feet.
*/
int
ping(struct _dom_binding *ypdb)
{
bool_t out;
struct timeval interval, timeout;
enum clnt_stat stat;
int rpcsock = RPC_ANYSOCK;
CLIENT *client_handle;
interval.tv_sec = FAIL_THRESHOLD;
interval.tv_usec = 0;
timeout.tv_sec = FAIL_THRESHOLD;
timeout.tv_usec = 0;
if (ypdb->dom_broadcast_pid)
return(1);
if ((client_handle = clntudp_bufcreate(&ypdb->dom_server_addr,
YPPROG, YPVERS, interval, &rpcsock, RPCSMALLMSGSIZE,
RPCSMALLMSGSIZE)) == (CLIENT *)NULL) {
/* Can't get a handle: we're dead. */
ypdb->dom_alive = 0;
ypdb->dom_vers = -1;
broadcast(ypdb);
return(1);
}
{
char *ptr;
ptr = ypdb->dom_domain;
stat = clnt_call(client_handle, YPPROC_DOMAIN,
(xdrproc_t)xdr_domainname, &ptr,
(xdrproc_t)xdr_bool, &out, timeout);
if (stat != RPC_SUCCESS || out == FALSE) {
ypdb->dom_alive = 0;
ypdb->dom_vers = -1;
clnt_destroy(client_handle);
broadcast(ypdb);
return(1);
}
}
clnt_destroy(client_handle);
return(0);
}
void
rpc_received(char *dom, struct sockaddr_in *raddrp, int force)
{
struct _dom_binding *ypdb, *prev = NULL;
struct iovec iov[2];
struct ypbind_resp ybr;
char path[MAXPATHLEN];
int fd;
/*printf("returned from %s/%d about %s\n", inet_ntoa(raddrp->sin_addr),
ntohs(raddrp->sin_port), dom);*/
if (dom == NULL)
return;
for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) {
if (strcmp(ypdb->dom_domain, dom) == 0)
break;
prev = ypdb;
}
if (ypdb && force) {
if (ypdb->dom_broadcast_pid) {
kill(ypdb->dom_broadcast_pid, SIGINT);
close(READFD);
FD_CLR(READFD, &fdsr);
FD_CLR(READFD, &svc_fdset);
READFD = WRITEFD = -1;
}
}
/* if in secure mode, check originating port number */
if ((ypsecuremode && (ntohs(raddrp->sin_port) >= IPPORT_RESERVED))) {
syslog(LOG_WARNING, "Rejected NIS server on [%s/%d] for domain %s.",
inet_ntoa(raddrp->sin_addr), ntohs(raddrp->sin_port),
dom);
if (ypdb != NULL) {
ypdb->dom_broadcast_pid = 0;
ypdb->dom_alive = 0;
}
return;
}
if (raddrp->sin_addr.s_addr == (long)0) {
switch (ypdb->dom_default) {
case 0:
if (prev == NULL)
ypbindlist = ypdb->dom_pnext;
else
prev->dom_pnext = ypdb->dom_pnext;
sprintf(path, "%s/%s.%ld", BINDINGDIR,
ypdb->dom_domain, YPVERS);
close(ypdb->dom_lockfd);
unlink(path);
free(ypdb);
domains--;
return;
case 1:
ypdb->dom_broadcast_pid = 0;
ypdb->dom_alive = 0;
broadcast(ypdb);
return;
default:
break;
}
}
if (ypdb == NULL) {
if (force == 0)
return;
if (strlen(dom) > YPMAXDOMAIN) {
syslog(LOG_WARNING, "domain %s too long", dom);
return;
}
ypdb = malloc(sizeof *ypdb);
if (ypdb == NULL) {
syslog(LOG_WARNING, "malloc: %m");
return;
}
bzero(ypdb, sizeof *ypdb);
strlcpy(ypdb->dom_domain, dom, sizeof ypdb->dom_domain);
ypdb->dom_lockfd = -1;
ypdb->dom_default = 0;
ypdb->dom_pnext = ypbindlist;
ypbindlist = ypdb;
}
/* We've recovered from a crash: inform the world. */
if (ypdb->dom_vers == -1 && ypdb->dom_server_addr.sin_addr.s_addr) {
if (not_responding_count >= NOT_RESPONDING_HYSTERESIS) {
not_responding_count = 0;
syslog(LOG_WARNING, "NIS server [%s] for domain \"%s\" OK",
inet_ntoa(raddrp->sin_addr), ypdb->dom_domain);
}
}
bcopy(raddrp, &ypdb->dom_server_addr,
sizeof ypdb->dom_server_addr);
ypdb->dom_vers = YPVERS;
ypdb->dom_alive = 1;
ypdb->dom_broadcast_pid = 0;
if (ypdb->dom_lockfd != -1)
close(ypdb->dom_lockfd);
sprintf(path, "%s/%s.%ld", BINDINGDIR,
ypdb->dom_domain, ypdb->dom_vers);
#ifdef O_SHLOCK
if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) {
(void)mkdir(BINDINGDIR, 0755);
if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1)
return;
}
#else
if ((fd = open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1) {
(void)mkdir(BINDINGDIR, 0755);
if ((fd = open(path, O_CREAT|O_RDWR|O_TRUNC, 0644)) == -1)
return;
}
flock(fd, LOCK_SH);
#endif
/*
* ok, if BINDINGDIR exists, and we can create the binding file,
* then write to it..
*/
ypdb->dom_lockfd = fd;
iov[0].iov_base = (char *)&(udptransp->xp_port);
iov[0].iov_len = sizeof udptransp->xp_port;
iov[1].iov_base = (char *)&ybr;
iov[1].iov_len = sizeof ybr;
bzero(&ybr, sizeof ybr);
ybr.ypbind_status = YPBIND_SUCC_VAL;
memcpy(&ybr.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_addr,
&raddrp->sin_addr.s_addr, sizeof(u_int32_t));
memcpy(&ybr.ypbind_resp_u.ypbind_bindinfo.ypbind_binding_port,
&raddrp->sin_port, sizeof(u_short));
if (writev(ypdb->dom_lockfd, iov, 2) != iov[0].iov_len + iov[1].iov_len) {
syslog(LOG_WARNING, "write: %m");
close(ypdb->dom_lockfd);
ypdb->dom_lockfd = -1;
return;
}
}
/*
* Check address against list of allowed servers. Return 0 if okay,
* 1 if not matched.
*/
int
verify(struct in_addr addr)
{
int i;
for (i = 0; i < RESTRICTED_SERVERS; i++)
if (!bcmp(&addr, &restricted_addrs[i], sizeof(struct in_addr)))
return(0);
return(1);
}
/*
* Try to set restricted mode. We default to normal mode if we can't
* resolve the specified hostnames.
*/
void
yp_restricted_mode(char *args)
{
struct hostent *h;
int i = 0;
char *s;
/* Find the restricted domain. */
if ((s = strsep(&args, ",")) == NULL)
return;
domain_name = s;
/* Get the addresses of the servers. */
while ((s = strsep(&args, ",")) != NULL && i < RESTRICTED_SERVERS) {
if ((h = gethostbyname(s)) == NULL)
return;
bcopy (h->h_addr_list[0], &restricted_addrs[i],
sizeof(struct in_addr));
i++;
}
/* ypset and ypsetme not allowed with restricted mode */
ypsetmode = YPSET_NO;
yp_restricted = i;
return;
}