inet/rexec.c

   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 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)rexec.c     8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 #include <sys/types.h>
  39 #include <sys/socket.h>
  40
  41 #include <netinet/in.h>
  42
  43 #include <alloca.h>
  44 #include <stdio.h>
  45 #include <netdb.h>
  46 #include <errno.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49
  50 int     rexecoptions;
  51
  52 int
  53 rexec(ahost, rport, name, pass, cmd, fd2p)
  54         char **ahost;
  55         int rport;
  56         const char *name, *pass, *cmd;
  57         int *fd2p;
  58 {
  59         struct sockaddr_in sin, sin2, from;
  60         struct hostent hostbuf, *hp;
  61         size_t hstbuflen;
  62         char *hsttmpbuf;
  63         u_short port;
  64         int s, timo = 1, s3;
  65         char c;
  66         int herr;
  67
  68         hstbuflen = 1024;
  69         hsttmpbuf = __alloca (hstbuflen);
  70         while (__gethostbyname_r (*ahost, &hostbuf, hsttmpbuf, hstbuflen,
  71                                   &hp, &herr) < 0)
  72           if (herr != NETDB_INTERNAL || errno != ERANGE)
  73             {
  74               __set_h_errno (herr);
  75               herror(*ahost);
  76               return -1;
  77             }
  78           else
  79             {
  80               /* Enlarge the buffer.  */
  81               hstbuflen *= 2;
  82               hsttmpbuf = __alloca (hstbuflen);
  83             }
  84
  85         *ahost = hp->h_name;
  86         ruserpass(hp->h_name, &name, &pass);
  87 retry:
  88         s = socket(AF_INET, SOCK_STREAM, 0);
  89         if (s < 0) {
  90                 perror("rexec: socket");
  91                 return (-1);
  92         }
  93         sin.sin_family = hp->h_addrtype;
  94         sin.sin_port = rport;
  95         bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
  96         if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
  97                 if (errno == ECONNREFUSED && timo <= 16) {
  98                         (void) close(s);
  99                         sleep(timo);
 100                         timo *= 2;
 101                         goto retry;
 102                 }
 103                 perror(hp->h_name);
 104                 return (-1);
 105         }
 106         if (fd2p == 0) {
 107                 (void) write(s, "", 1);
 108                 port = 0;
 109         } else {
 110                 char num[32];
 111                 int s2, sin2len;
 112
 113                 s2 = socket(AF_INET, SOCK_STREAM, 0);
 114                 if (s2 < 0) {
 115                         (void) close(s);
 116                         return (-1);
 117                 }
 118                 listen(s2, 1);
 119                 sin2len = sizeof (sin2);
 120                 if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
 121                   sin2len != sizeof (sin2)) {
 122                         perror("getsockname");
 123                         (void) close(s2);
 124                         goto bad;
 125                 }
 126                 port = ntohs((u_short)sin2.sin_port);
 127                 (void) sprintf(num, "%u", port);
 128                 (void) write(s, num, strlen(num)+1);
 129                 { int len = sizeof (from);
 130                   s3 = accept(s2, (struct sockaddr *)&from, &len);
 131                   close(s2);
 132                   if (s3 < 0) {
 133                         perror("accept");
 134                         port = 0;
 135                         goto bad;
 136                   }
 137                 }
 138                 *fd2p = s3;
 139         }
 140         (void) write(s, name, strlen(name) + 1);
 141         /* should public key encypt the password here */
 142         (void) write(s, pass, strlen(pass) + 1);
 143         (void) write(s, cmd, strlen(cmd) + 1);
 144         if (read(s, &c, 1) != 1) {
 145                 perror(*ahost);
 146                 goto bad;
 147         }
 148         if (c != 0) {
 149                 while (read(s, &c, 1) == 1) {
 150                         (void) write(2, &c, 1);
 151                         if (c == '\n')
 152                                 break;
 153                 }
 154                 goto bad;
 155         }
 156         return (s);
 157 bad:
 158         if (port)
 159                 (void) close(*fd2p);
 160         (void) close(s);
 161         return (-1);
 162 }