NetBSD-5.0.2/usr.sbin/rpcbind/security.c
/* $NetBSD: security.c,v 1.10 2007/05/16 14:42:08 christos Exp $ */
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <rpc/rpc.h>
#include <rpc/rpcb_prot.h>
#include <rpc/pmap_prot.h>
#include <err.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
#include <syslog.h>
#include <netdb.h>
/*
* XXX for special case checks in check_callit.
*/
#include <rpcsvc/mount.h>
#include <rpcsvc/rquota.h>
#include <rpcsvc/nfs_prot.h>
#include <rpcsvc/yp.h>
#include <rpcsvc/ypclnt.h>
#include <rpcsvc/yppasswd.h>
#include "rpcbind.h"
#ifdef LIBWRAP
# include <tcpd.h>
#ifndef LIBWRAP_ALLOW_FACILITY
# define LIBWRAP_ALLOW_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_ALLOW_SEVERITY
# define LIBWRAP_ALLOW_SEVERITY LOG_INFO
#endif
#ifndef LIBWRAP_DENY_FACILITY
# define LIBWRAP_DENY_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_DENY_SEVERITY
# define LIBWRAP_DENY_SEVERITY LOG_WARNING
#endif
int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
#endif
#ifndef PORTMAP_LOG_FACILITY
# define PORTMAP_LOG_FACILITY LOG_AUTH
#endif
#ifndef PORTMAP_LOG_SEVERITY
# define PORTMAP_LOG_SEVERITY LOG_INFO
#endif
int log_severity = PORTMAP_LOG_FACILITY|PORTMAP_LOG_SEVERITY;
extern int verboselog;
int
check_access(SVCXPRT *xprt, rpcproc_t proc, void *args, int rpcbvers)
{
struct netbuf *caller = svc_getrpccaller(xprt);
struct sockaddr *addr = (struct sockaddr *)caller->buf;
#ifdef LIBWRAP
struct request_info req;
#endif
rpcprog_t prog = 0;
rpcb *rpcbp;
struct pmap *pmap;
/*
* The older PMAP_* equivalents have the same numbers, so
* they are accounted for here as well.
*/
switch (proc) {
case RPCBPROC_GETADDR:
case RPCBPROC_SET:
case RPCBPROC_UNSET:
if (rpcbvers > PMAPVERS) {
rpcbp = (rpcb *)args;
prog = rpcbp->r_prog;
} else {
pmap = (struct pmap *)args;
prog = pmap->pm_prog;
}
if (proc == RPCBPROC_GETADDR)
break;
if (!insecure && !is_loopback(caller)) {
if (verboselog)
logit(log_severity, addr, proc, prog,
" declined (non-loopback sender)");
return 0;
}
break;
case RPCBPROC_CALLIT:
case RPCBPROC_INDIRECT:
case RPCBPROC_DUMP:
case RPCBPROC_GETTIME:
case RPCBPROC_UADDR2TADDR:
case RPCBPROC_TADDR2UADDR:
case RPCBPROC_GETVERSADDR:
case RPCBPROC_GETADDRLIST:
case RPCBPROC_GETSTAT:
default:
break;
}
#ifdef LIBWRAP
if (addr->sa_family == AF_LOCAL)
return 1;
request_init(&req, RQ_DAEMON, "rpcbind", RQ_CLIENT_SIN, addr, 0);
sock_methods(&req);
if(!hosts_access(&req)) {
logit(deny_severity, addr, proc, prog, ": request from unauthorized host");
return 0;
}
#endif
if (verboselog)
logit(log_severity, addr, proc, prog, "");
return 1;
}
int
is_loopback(struct netbuf *nbuf)
{
struct sockaddr *addr = (struct sockaddr *)nbuf->buf;
struct sockaddr_in *sin;
#ifdef INET6
struct sockaddr_in6 *sin6;
#endif
switch (addr->sa_family) {
case AF_INET:
if (!oldstyle_local)
return 0;
sin = (struct sockaddr_in *)addr;
return ((sin->sin_addr.s_addr == htonl(INADDR_LOOPBACK)) &&
(ntohs(sin->sin_port) < IPPORT_RESERVED));
#ifdef INET6
case AF_INET6:
if (!oldstyle_local)
return 0;
sin6 = (struct sockaddr_in6 *)addr;
return (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr) &&
(ntohs(sin6->sin6_port) < IPV6PORT_RESERVED));
#endif
case AF_LOCAL:
return 1;
default:
break;
}
return 0;
}
/* logit - report events of interest via the syslog daemon */
void
logit(int severity, struct sockaddr *addr, rpcproc_t procnum, rpcprog_t prognum,
const char *text)
{
const char *procname;
char procbuf[32];
char *progname;
char progbuf[32];
char fromname[NI_MAXHOST];
struct rpcent *rpc;
static const char *procmap[] = {
/* RPCBPROC_NULL */ "null",
/* RPCBPROC_SET */ "set",
/* RPCBPROC_UNSET */ "unset",
/* RPCBPROC_GETADDR */ "getport/addr",
/* RPCBPROC_DUMP */ "dump",
/* RPCBPROC_CALLIT */ "callit",
/* RPCBPROC_GETTIME */ "gettime",
/* RPCBPROC_UADDR2TADDR */ "uaddr2taddr",
/* RPCBPROC_TADDR2UADDR */ "taddr2uaddr",
/* RPCBPROC_GETVERSADDR */ "getversaddr",
/* RPCBPROC_INDIRECT */ "indirect",
/* RPCBPROC_GETADDRLIST */ "getaddrlist",
/* RPCBPROC_GETSTAT */ "getstat"
};
/*
* Fork off a process or the portmap daemon might hang while
* getrpcbynumber() or syslog() does its thing.
*/
if (fork() == 0) {
setproctitle("logit");
/* Try to map program number to name. */
if (prognum == 0) {
progname = __UNCONST("");
} else if ((rpc = getrpcbynumber((int) prognum))) {
progname = rpc->r_name;
} else {
snprintf(progname = progbuf, sizeof(progbuf), "%u",
(unsigned)prognum);
}
/* Try to map procedure number to name. */
if (procnum >= (sizeof procmap / sizeof (char *))) {
snprintf(procbuf, sizeof procbuf, "%u",
(unsigned)procnum);
procname = procbuf;
} else
procname = procmap[procnum];
/* Write syslog record. */
if (addr->sa_family == AF_LOCAL)
strlcpy(fromname, "local", sizeof(fromname));
else
getnameinfo(addr, addr->sa_len, fromname,
sizeof fromname, NULL, 0, NI_NUMERICHOST);
syslog(severity, "connect from %s to %s(%s)%s",
fromname, procname, progname, text);
_exit(0);
}
}
int
check_callit(SVCXPRT *xprt, struct r_rmtcall_args *args, int versnum)
{
struct sockaddr *sa = (struct sockaddr *)svc_getrpccaller(xprt)->buf;
/*
* Always allow calling NULLPROC
*/
if (args->rmt_proc == 0)
return 1;
/*
* XXX - this special casing sucks.
*/
switch (args->rmt_prog) {
case RPCBPROG:
/*
* Allow indirect calls to ourselves in insecure mode.
* The is_loopback checks aren't useful then anyway.
*/
if (!insecure)
goto deny;
break;
case MOUNTPROG:
if (args->rmt_proc != MOUNTPROC_MNT &&
args->rmt_proc != MOUNTPROC_UMNT)
break;
goto deny;
case YPBINDPROG:
if (args->rmt_proc != YPBINDPROC_SETDOM)
break;
/* FALLTHROUGH */
case YPPASSWDPROG:
case NFS_PROGRAM:
case RQUOTAPROG:
goto deny;
case YPPROG:
switch (args->rmt_proc) {
case YPPROC_ALL:
case YPPROC_MATCH:
case YPPROC_FIRST:
case YPPROC_NEXT:
goto deny;
default:
break;
}
default:
break;
}
return 1;
deny:
logit(deny_severity, sa, args->rmt_proc, args->rmt_prog,
": indirect call not allowed");
return 0;
}