Bring in a hybrid of SunSoft's transport-independent RPC (TI-RPC) and

associated changes that had to happen to make this possible as well as
bugs fixed along the way.

  Bring in required TLI library routines to support this.

  Since we don't support TLI we've essentially copied what NetBSD
  has done, adding a thin layer to emulate direct the TLI calls
  into BSD socket calls.

  This is mostly from Sun's tirpc release that was made in 1994,
  however some fixes were backported from the 1999 release (supposedly
  only made available after this porting effort was underway).

  The submitter has agreed to continue on and bring us up to the
  1999 release.

  Several key features are introduced with this update:
    Client calls are thread safe. (1999 code has server side thread
    safe)
    Updated, a more modern interface.

  Many userland updates were done to bring the code up to par with
  the recent RPC API.

  There is an update to the pthreads library, a function
  pthread_main_np() was added to emulate a function of Sun's threads
  library.

  While we're at it, bring in NetBSD's lockd, it's been far too
  long of a wait.

  New rpcbind(8) replaces portmap(8) (supporting communication over
  an authenticated Unix-domain socket, and by default only allowing
  set and unset requests over that channel). It's much more secure
  than the old portmapper.

  Umount(8), mountd(8), mount_nfs(8), nfsd(8) have also been upgraded
  to support TI-RPC and to support IPV6.

  Umount(8) is also fixed to unmount pathnames longer than 80 chars,
  which are currently truncated by the Kernel statfs structure.

Submitted by: Martin Blapp <mb@imp.ch>
Manpage review: ru
Secure RPC implemented by: wpaul

1 files changed, 283 insertions, 0 deletions

diff --git a/usr.sbin/rpcbind/security.c b/usr.sbin/rpcbind/security.c
new file mode 100644
index 0000000..8d784d6
--- /dev/null
+++ b/usr.sbin/rpcbind/security.c
@@ -0,0 +1,283 @@
+/*	$NetBSD: security.c,v 1.5 2000/06/08 09:01:05 fvdl Exp $	*/
+/*	$FreeBSD$ */
+
+#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 <libutil.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:
+	}
+
+#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:
+	}
+	
+	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 = "";
+		} 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)
+			strcpy(fromname, "unix");
+		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:
+		}
+	default:
+	}
+
+	return 1;
+deny:
+#ifdef LIBWRAP
+	logit(deny_severity, sa, args->rmt_proc, args->rmt_prog,
+	    ": indirect call not allowed");
+#else
+	logit(0, sa, args->rmt_proc, args->rmt_prog,
+	    ": indirect call not allowed");
+#endif
+	return 0;
+}