1 files changed, 300 insertions, 0 deletions
diff --git a/usr.sbin/rpc.yppasswdd/yppasswd_comm.c b/usr.sbin/rpc.yppasswdd/yppasswd_comm.c
new file mode 100644
index 0000000..d43d961
--- /dev/null
+++ b/usr.sbin/rpc.yppasswdd/yppasswd_comm.c
@@ -0,0 +1,300 @@
+/*
+ * Copyright (c) 1995, 1996
+ *	Bill Paul <wpaul@ctr.columbia.edu>.  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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Bill Paul.
+ * 4. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``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 Bill Paul OR CONTRIBUTORS 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.
+ *
+ *	$Id: yppasswd_comm.c,v 1.10 1996/02/03 04:41:59 wpaul Exp $
+ */
+
+/*
+ * This file contains a UNIX domain socket communications package
+ * that lets a client process send pseudo-RPCs to rpc.yppasswdd
+ * without using IP. This 'local-only' communications channel is
+ * only used when the superuser runs passwd(1) or chpass(1) on
+ * the NIS master server. The idea is that we want to grant the
+ * superuser permission to perfom certain special operations, but
+ * we need an iron-clad way to tell when we're receiving a request
+ * from the superuser and when we aren't. To connect to a UNIX
+ * domain socket, one needs to be able to access a file in the
+ * filesystem. The socket created by rpc.yppasswdd is owned by
+ * root and has all its permission bits cleared, so the only
+ * user who can sucessfully connect() to it is root.
+ *
+ * It is the server's responsibility to initialize the listening
+ * socket with the makeservsock() function and to add the socket to
+ * the set of file descriptors monitored by the svc_run() loop.
+ * Once this is done, calls made through the UNIX domain socket
+ * can be handled almost exactly like a normal RPC. We even use
+ * the XDR functions for serializing data between the client and
+ * server to simplify the passing of complex data structures.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <err.h>
+#include <errno.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/fcntl.h>
+#include <rpc/rpc.h>
+#include <rpcsvc/yp.h>
+#include "yppasswd_comm.h"
+#include "yppasswd_private.h"
+#include "ypxfr_extern.h"
+
+#ifndef lint
+static const char rcsid[] = "$Id: yppasswd_comm.c,v 1.10 1996/02/03 04:41:59 wpaul Exp $";
+#endif
+
+char *sockname = "/var/run/ypsock";
+FILE *serv_fp;
+FILE *clnt_fp;
+int serv_sock;
+int clnt_sock;
+
+/*
+ * serialize_data() and serialize_resp() are what really do most of
+ * the work. These functions (ab)use xdrstdio_create() as the interface
+ * to the XDR library. The RPC library uses xdrrec_create() and friends
+ * for TCP based connections. I suppose we could use that here, but
+ * the interface is a bit too complicated to justify using in an
+ * applicatuion such as this. With xdrstdio_create(), the only catch
+ * is that we need to provide a buffered file stream rather than
+ * a simple socket descriptor, but we can easily turn the latter into
+ * the former using fdopen(2).
+ *
+ * Doing things this way buys us the ability to change the form of
+ * the data being exchanged without having to modify any of the
+ * routines in this package.
+ */
+static int serialize_data(data, fp, op)
+	struct master_yppasswd *data;
+	FILE *fp;
+	int op;
+{
+	XDR xdrs;
+
+	xdrstdio_create(&xdrs, fp, op);
+
+	if (!xdr_master_yppasswd(&xdrs, data)) {
+		xdr_destroy(&xdrs);
+		return(1);
+	}
+	return(0);
+}
+
+static int serialize_resp(resp, fp, op)
+	int *resp;
+	FILE *fp;
+	int op;
+{
+	XDR xdrs;
+
+	xdrstdio_create(&xdrs, fp, op);
+
+	if (!xdr_int(&xdrs, resp)) {
+		xdr_destroy(&xdrs);
+		return(1);
+	}
+	return(0);
+}
+
+/*
+ * Build the server's listening socket. The descriptor generated
+ * here will be monitored for new connections by the svc_run() loop.
+ */
+int makeservsock()
+{
+	static int ypsock;
+	struct sockaddr_un us;
+	int len;
+
+	unlink(sockname);
+
+	if ((ypsock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
+		err(1, "failed to create UNIX domain socket");
+
+	bzero((char *)&us, sizeof(us));
+	us.sun_family = AF_UNIX;
+	strcpy((char *)&us.sun_path, sockname);
+	len = strlen(us.sun_path) + sizeof(us.sun_family) + 1;
+	
+	if (bind(ypsock, (struct sockaddr *)&us, len) == -1)
+		err(1,"failed to bind UNIX domain socket");
+
+	listen (ypsock, 1);
+
+	return(ypsock);
+}
+
+/*
+ * Create a socket for a client and try to connect() it to the
+ * server.
+ */
+static int makeclntsock()
+{
+	static int ypsock;
+	struct sockaddr_un us;
+	int len;
+
+	if ((ypsock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
+		warn("failed to create UNIX domain socket");
+		return(-1);
+	}
+
+	bzero((char *)&us, sizeof(us));
+	us.sun_family = AF_UNIX;
+	strcpy((char *)&us.sun_path, sockname);
+	len = strlen(us.sun_path) + sizeof(us.sun_family) + 1;
+
+	if (connect(ypsock, (struct sockaddr *)&us, len) == -1) {
+		warn("failed to connect to server");
+		return(-1);
+	}
+
+	return(ypsock);
+}
+
+/*
+ * This function is used by the server to accept a new connection
+ * from a client and read its request data into a master_yppasswd
+ * stucture.
+ */
+struct master_yppasswd *getdat(sock)
+	int sock;
+{
+	int len;
+	struct sockaddr_un us;
+	static struct master_yppasswd pw;
+	struct timeval tv;
+	fd_set fds;
+
+	FD_ZERO(&fds);
+	FD_SET(sock, &fds);
+
+	tv.tv_sec =  CONNECTION_TIMEOUT;
+	tv.tv_usec = 0;
+
+	switch(select(FD_SETSIZE, &fds, NULL, NULL, &tv)) {
+	case 0:
+		yp_error("select timed out");
+		return(NULL);
+		break;
+	case -1:
+		yp_error("select() failed: %s", strerror(errno));
+		return(NULL);
+		break;
+	default:
+		break;
+	}
+
+	if ((serv_sock = accept(sock, (struct sockaddr *)&us, &len)) == -1) {
+		yp_error("accept failed: %s", strerror(errno));
+		return(NULL);
+	}
+
+	if ((serv_fp = fdopen(serv_sock, "r+")) == NULL) {
+		yp_error("fdopen failed: %s",strerror(errno));
+		return(NULL);
+	}
+
+	if (serialize_data(&pw, serv_fp, XDR_DECODE)) {
+		yp_error("failed to receive data");
+		return(NULL);
+	}
+
+	return(&pw);
+}
+
+/*
+ * Client uses this to read back a response code (a single
+ * integer) from the server. Note that we don't need to implement
+ * any special XDR function for this since an int is a base data
+ * type which the XDR library can handle directly.
+ */
+int *getresp()
+{
+	static int resp;
+
+	if (serialize_resp(&resp, clnt_fp, XDR_DECODE)) {
+		warn("failed to receive response");
+		return(NULL);
+	}
+
+	fclose(clnt_fp);
+	close(clnt_sock);
+	return(&resp);
+}
+
+/*
+ * Create a connection to the server and send a reqest
+ * to be processed.
+ */
+int senddat(pw)
+	struct master_yppasswd *pw;
+{
+
+	if ((clnt_sock = makeclntsock()) == -1) {
+		warn("failed to create socket");
+		return(1);
+	}
+
+	if ((clnt_fp = fdopen(clnt_sock, "r+")) == NULL) {
+		warn("fdopen failed");
+		return(1);
+	}
+
+	if (serialize_data(pw, clnt_fp, XDR_ENCODE)) {
+		warn("failed to send data");
+		return(1);
+	}
+
+	return(0);
+}
+
+/*
+ * This sends a response code back to the client.
+ */
+int sendresp(resp)
+	int resp;
+{
+
+	if (serialize_resp(&resp, serv_fp, XDR_ENCODE)) {
+		yp_error("failed to send response");
+		return(-1);
+	}
+
+	fclose(serv_fp);
+	close(serv_sock);
+	return(0);
+}