/*- * Copyright (c) 1983, 1990, 1993, 1994 * The Regents of the University of California. 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 the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS 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. */ #ifndef lint static char copyright[] = "@(#) Copyright (c) 1983, 1990, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint static char sccsid[] = "@(#)rsh.c 8.4 (Berkeley) 4/29/95"; #endif /* not lint */ /* * $Source: /home/gd4/gnu/cvsroot/inetutils/rsh/rsh.c,v $ * $Header: /home/gd4/gnu/cvsroot/inetutils/rsh/rsh.c,v 1.11 1997/02/17 04:31:46 miles Exp $ */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #ifdef HAVE_SYS_FILIO_H #include #endif #include #ifdef TIME_WITH_SYS_TIME # include # include #else # ifdef HAVE_SYS_TIME_H # include # else # include # endif #endif #include #include #include #include #include #include #include #include #include #include #if defined(HAVE_STDARG_H) && defined(__STDC__) && __STDC__ #include #else #include #endif #include #ifdef HAVE_SYS_SELECT_H #include #endif #ifdef KERBEROS #include #include CREDENTIALS cred; Key_schedule schedule; int use_kerberos = 1, doencrypt; char dst_realm_buf[REALM_SZ], *dest_realm; extern char *krb_realmofhost(); #endif #include "version.h" /* * rsh - remote shell */ int rfd2; char *copyargs __P((char **)); void sendsig __P((int)); void talk __P((int, sigset_t *, pid_t, int)); void usage __P((void)); void warning __P((const char *, ...)); /* basename (argv[0]). NetBSD, linux, & gnu libc all define it. */ extern char *__progname; static struct option long_options[] = { { "debug", no_argument, 0, 'd' }, { "no-input", no_argument, 0, 'n' }, { "user", required_argument, 0, 'l' }, { "encrypt", no_argument, 0, 'x' }, { "realm", required_argument, 0, 'k' }, { "help", no_argument, 0, '&' }, { "version", no_argument, 0, 'V' }, { 0 } }; static void pusage (stream) FILE *stream; { fprintf(stream, "Usage: %s [-nd%s]%s[-l USER] [USER@]HOST [COMMAND [ARG...]]\n", __progname, #ifdef KERBEROS #ifdef CRYPT "x", " [-k REALM] "); #else "", " [-k REALM] "); #endif #else "", " "); #endif } /* Print a help message describing all options to STDOUT and exit with a status of 0. */ static void help () { pusage (stdout); puts ("Execute COMMAND on remote system HOST\n\n\ -d, --debug Turn on socket debugging"); #ifdef KERBEROS puts ("\ -k REALM, --realm=REALM Obtain tickets for the remote host in REALM\n\ instead of the remote host's realm"); #endif puts ("\ -l USER, --user=USER Run as USER on the remote system"); puts ("\ -n, --no-input Use /dev/null as input"); #ifdef CRYPT puts ("\ -x, --encrypt Encrypt all data using DES"); #endif puts ("\ --help Give this help list\n\ -V, --version Print program version"); fprintf (stdout, "\nSubmit bug reports to %s.\n", inetutils_bugaddr); exit (0); } /* Print a message saying to use --help to STDERR, and exit with a status of 1. */ static void try_help () { fprintf (stderr, "Try `%s --help' for more information.\n", __progname); exit (1); } void usage() { pusage (stderr); try_help (); } int main(argc, argv) int argc; char **argv; { struct passwd *pw; struct servent *sp; sigset_t sigs, osigs; int argoff, asrsh, ch, dflag, nflag, one, rem; pid_t pid; uid_t uid; char *args, *host, *p, *user; #ifndef HAVE___PROGNAME extern char *__progname; __progname = argv[0]; #endif argoff = asrsh = dflag = nflag = 0; one = 1; host = user = NULL; /* if called as something other than "rsh", use it as the host name */ if (p = strrchr(argv[0], '/')) ++p; else p = argv[0]; if (strcmp(p, "rsh")) host = p; else asrsh = 1; /* handle "rsh host flags" */ if (!host && argc > 2 && argv[1][0] != '-') { host = argv[1]; argoff = 1; } #ifdef KERBEROS #ifdef CRYPT #define OPTIONS "8KLdek:l:nwx" #else #define OPTIONS "8KLdek:l:nw" #endif #else #define OPTIONS "8KLdel:nw" #endif while ((ch = getopt_long (argc - argoff, argv + argoff, OPTIONS, long_options, 0)) != EOF) switch(ch) { case 'K': #ifdef KERBEROS use_kerberos = 0; #endif break; case 'L': /* -8Lew are ignored to allow rlogin aliases */ case 'e': case 'w': case '8': break; case 'd': dflag = 1; break; case 'l': user = optarg; break; #ifdef KERBEROS case 'k': dest_realm = dst_realm_buf; strncpy(dest_realm, optarg, REALM_SZ); break; #endif case 'n': nflag = 1; break; #ifdef KERBEROS #ifdef CRYPT case 'x': doencrypt = 1; des_set_key(cred.session, schedule); break; #endif #endif case '&': help (); case 'V': printf ("rsh (%s) %s\n", inetutils_package, inetutils_version); exit (0); case '?': try_help (); default: usage(); } optind += argoff; /* if haven't gotten a host yet, do so */ if (!host && !(host = argv[optind++])) usage(); /* if no further arguments, must have been called as rlogin. */ if (!argv[optind]) { if (asrsh) *argv = "rlogin"; execv(PATH_RLOGIN, argv); err(1, "can't exec %s", PATH_RLOGIN); } argc -= optind; argv += optind; if (!(pw = getpwuid(uid = getuid()))) errx(1, "unknown user id"); /* Accept user1@host format, though "-l user2" overrides user1 */ p = strchr(host, '@'); if (p) { *p = '\0'; if (!user && p > host) user = host; host = p + 1; if (*host == '\0') usage(); } if (!user) user = pw->pw_name; #ifdef KERBEROS #ifdef CRYPT /* -x turns off -n */ if (doencrypt) nflag = 0; #endif #endif args = copyargs(argv); sp = NULL; #ifdef KERBEROS if (use_kerberos) { sp = getservbyname((doencrypt ? "ekshell" : "kshell"), "tcp"); if (sp == NULL) { use_kerberos = 0; warning("can't get entry for %s/tcp service", doencrypt ? "ekshell" : "kshell"); } } #endif if (sp == NULL) sp = getservbyname("shell", "tcp"); if (sp == NULL) errx(1, "shell/tcp: unknown service"); #ifdef KERBEROS try_connect: if (use_kerberos) { struct hostent *hp; /* fully qualify hostname (needed for krb_realmofhost) */ hp = gethostbyname(host); if (hp != NULL && !(host = strdup(hp->h_name))) err(1, NULL); rem = KSUCCESS; errno = 0; if (dest_realm == NULL) dest_realm = krb_realmofhost(host); #ifdef CRYPT if (doencrypt) rem = krcmd_mutual(&host, sp->s_port, user, args, &rfd2, dest_realm, &cred, schedule); else #endif rem = krcmd(&host, sp->s_port, user, args, &rfd2, dest_realm); if (rem < 0) { use_kerberos = 0; sp = getservbyname("shell", "tcp"); if (sp == NULL) errx(1, "shell/tcp: unknown service"); if (errno == ECONNREFUSED) warning("remote host doesn't support Kerberos"); if (errno == ENOENT) warning("can't provide Kerberos auth data"); goto try_connect; } } else { if (doencrypt) errx(1, "the -x flag requires Kerberos authentication"); rem = rcmd(&host, sp->s_port, pw->pw_name, user, args, &rfd2); } #else rem = rcmd(&host, sp->s_port, pw->pw_name, user, args, &rfd2); #endif if (rem < 0) exit(1); if (rfd2 < 0) errx(1, "can't establish stderr"); if (dflag) { if (setsockopt(rem, SOL_SOCKET, SO_DEBUG, (char *) &one, sizeof(one)) < 0) warn("setsockopt"); if (setsockopt(rfd2, SOL_SOCKET, SO_DEBUG, (char *) &one, sizeof(one)) < 0) warn("setsockopt"); } (void)setuid(uid); #ifdef HAVE_SIGACTION sigemptyset(&sigs); sigaddset(&sigs, SIGINT); sigaddset(&sigs, SIGQUIT); sigaddset(&sigs, SIGTERM); sigprocmask(SIG_BLOCK, &sigs, &osigs); #else sigs = sigmask (SIGINT) | sigmask (SIGQUIT) | sigmask (SIGTERM); osigs = sigblock (sigs); #endif if (signal(SIGINT, SIG_IGN) != SIG_IGN) (void)signal(SIGINT, sendsig); if (signal(SIGQUIT, SIG_IGN) != SIG_IGN) (void)signal(SIGQUIT, sendsig); if (signal(SIGTERM, SIG_IGN) != SIG_IGN) (void)signal(SIGTERM, sendsig); if (!nflag) { pid = fork(); if (pid < 0) err(1, "fork"); } #ifdef KERBEROS #ifdef CRYPT if (!doencrypt) #endif #endif { (void)ioctl(rfd2, FIONBIO, &one); (void)ioctl(rem, FIONBIO, &one); } talk(nflag, &osigs, pid, rem); if (!nflag) (void)kill(pid, SIGKILL); exit(0); } void talk (nflag, osigs, pid, rem) int nflag; sigset_t *osigs; pid_t pid; int rem; { int cc, wc; fd_set readfrom, ready, rembits; char *bp, buf[BUFSIZ]; if (!nflag && pid == 0) { (void)close(rfd2); reread: errno = 0; if ((cc = read(0, buf, sizeof buf)) <= 0) goto done; bp = buf; rewrite: FD_ZERO(&rembits); FD_SET(rem, &rembits); if (select(16, 0, &rembits, 0, 0) < 0) { if (errno != EINTR) err(1, "select"); goto rewrite; } if (!FD_ISSET(rem, &rembits)) goto rewrite; #ifdef KERBEROS #ifdef CRYPT if (doencrypt) wc = des_write(rem, bp, cc); else #endif #endif wc = write(rem, bp, cc); if (wc < 0) { if (errno == EWOULDBLOCK) goto rewrite; goto done; } bp += wc; cc -= wc; if (cc == 0) goto reread; goto rewrite; done: (void)shutdown(rem, 1); exit(0); } #ifdef HAVE_SIGACTION sigprocmask (SIG_SETMASK, osigs, 0); #else sigsetmask (*osigs); #endif FD_ZERO(&readfrom); FD_SET(rfd2, &readfrom); FD_SET(rem, &readfrom); do { ready = readfrom; if (select(16, &ready, 0, 0, 0) < 0) { if (errno != EINTR) err(1, "select"); continue; } if (FD_ISSET(rfd2, &ready)) { errno = 0; #ifdef KERBEROS #ifdef CRYPT if (doencrypt) cc = des_read(rfd2, buf, sizeof buf); else #endif #endif cc = read(rfd2, buf, sizeof buf); if (cc <= 0) { if (errno != EWOULDBLOCK) FD_CLR(rfd2, &readfrom); } else (void)write(2, buf, cc); } if (FD_ISSET(rem, &ready)) { errno = 0; #ifdef KERBEROS #ifdef CRYPT if (doencrypt) cc = des_read(rem, buf, sizeof buf); else #endif #endif cc = read(rem, buf, sizeof buf); if (cc <= 0) { if (errno != EWOULDBLOCK) FD_CLR(rem, &readfrom); } else (void)write(1, buf, cc); } } while (FD_ISSET(rfd2, &readfrom) || FD_ISSET(rem, &readfrom)); } void sendsig(sig) int sig; { char signo; signo = sig; #ifdef KERBEROS #ifdef CRYPT if (doencrypt) (void)des_write(rfd2, &signo, 1); else #endif #endif (void)write(rfd2, &signo, 1); } #ifdef KERBEROS /* VARARGS */ void #if defined(HAVE_STDARG_H) && defined(__STDC__) && __STDC__ warning(const char * fmt, ...) #else warning(va_alist) va_dcl #endif { va_list ap; #if !(defined(HAVE_STDARG_H) && defined(__STDC__) && __STDC__) const char *fmt; #endif fprintf(stderr, "%s: warning, using standard rsh: ", __progname); #if defined(HAVE_STDARG_H) && defined(__STDC__) && __STDC__ va_start(ap, fmt); #else va_start(ap); #endif fmt = va_arg(ap, char *); vfprintf(stderr, fmt, ap); va_end(ap); (void)fprintf(stderr, ".\n"); } #endif char * copyargs(argv) char **argv; { int cc; char **ap, *args, *p; cc = 0; for (ap = argv; *ap; ++ap) cc += strlen(*ap) + 1; if (!(args = malloc((u_int)cc))) err(1, NULL); for (p = args, ap = argv; *ap; ++ap) { (void)strcpy(p, *ap); for (p = strcpy(p, *ap); *p; ++p); if (ap[1]) *p++ = ' '; } return (args); }