rexec.c revision 1.7 1 /*
2 * Copyright (c) 1980, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <sys/cdefs.h>
35 #if defined(LIBC_SCCS) && !defined(lint)
36 #if 0
37 static char sccsid[] = "@(#)rexec.c 8.1 (Berkeley) 6/4/93";
38 #else
39 __RCSID("$NetBSD: rexec.c,v 1.7 1998/03/19 18:06:15 tv Exp $");
40 #endif
41 #endif /* LIBC_SCCS and not lint */
42
43 #include <sys/types.h>
44 #include <sys/socket.h>
45
46 #include <netinet/in.h>
47
48 #include <stdio.h>
49 #include <netdb.h>
50 #include <string.h>
51 #include <errno.h>
52 #include <unistd.h>
53
54 int rexecoptions;
55
56 int ruserpass __P((const char *, char **, char **));
57 int rexec __P((char **, int, char *, char *, char *, int *));
58
59 int
60 rexec(ahost, rport, name, pass, cmd, fd2p)
61 char **ahost;
62 int rport;
63 char *name, *pass, *cmd;
64 int *fd2p;
65 {
66 struct sockaddr_in sin, sin2, from;
67 struct hostent *hp;
68 u_short port;
69 int s, timo = 1, s3;
70 char c;
71
72 hp = gethostbyname(*ahost);
73 if (hp == 0) {
74 herror(*ahost);
75 return (-1);
76 }
77 *ahost = hp->h_name;
78 (void)ruserpass(hp->h_name, &name, &pass);
79 retry:
80 s = socket(AF_INET, SOCK_STREAM, 0);
81 if (s < 0) {
82 perror("rexec: socket");
83 return (-1);
84 }
85 sin.sin_family = hp->h_addrtype;
86 sin.sin_len = sizeof(sin);
87 sin.sin_port = rport;
88 bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
89 if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
90 if (errno == ECONNREFUSED && timo <= 16) {
91 (void) close(s);
92 sleep(timo);
93 timo *= 2;
94 goto retry;
95 }
96 perror(hp->h_name);
97 return (-1);
98 }
99 port = 0;
100 if (fd2p == 0) {
101 (void) write(s, "", 1);
102 } else {
103 char num[8];
104 int s2, sin2len;
105
106 s2 = socket(AF_INET, SOCK_STREAM, 0);
107 if (s2 < 0) {
108 (void) close(s);
109 return (-1);
110 }
111 listen(s2, 1);
112 sin2len = sizeof (sin2);
113 if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
114 sin2len != sizeof (sin2)) {
115 perror("getsockname");
116 (void) close(s2);
117 goto bad;
118 }
119 port = ntohs((u_short)sin2.sin_port);
120 (void)snprintf(num, sizeof num, "%u", port);
121 (void) write(s, num, strlen(num)+1);
122 { int len = sizeof (from);
123 s3 = accept(s2, (struct sockaddr *)&from, &len);
124 close(s2);
125 if (s3 < 0) {
126 perror("accept");
127 port = 0;
128 goto bad;
129 }
130 }
131 *fd2p = s3;
132 }
133 (void) write(s, name, strlen(name) + 1);
134 /* should public key encypt the password here */
135 (void) write(s, pass, strlen(pass) + 1);
136 (void) write(s, cmd, strlen(cmd) + 1);
137 if (read(s, &c, 1) != 1) {
138 perror(*ahost);
139 goto bad;
140 }
141 if (c != 0) {
142 while (read(s, &c, 1) == 1) {
143 (void) write(2, &c, 1);
144 if (c == '\n')
145 break;
146 }
147 goto bad;
148 }
149 return (s);
150 bad:
151 if (port)
152 (void) close(*fd2p);
153 (void) close(s);
154 return (-1);
155 }
156