#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: rcmdsh.c,v 1.4 1997/07/23 16:59:37 millert Exp $";
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <signal.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <pwd.h>
#include <paths.h>
#include <unistd.h>
int
rcmdsh(ahost, rport, locuser, remuser, cmd, rshprog)
char **ahost;
int rport;
const char *locuser, *remuser, *cmd;
char *rshprog;
{
struct hostent *hp;
int cpid, sp[2];
char *p;
struct passwd *pw;
if (rshprog == NULL)
rshprog = _PATH_RSH;
if ((pw = getpwnam(locuser)) == NULL) {
(void) fprintf(stderr, "rcmdsh: unknown user: %s\n", locuser);
return(-1);
}
if (strcmp(*ahost, "localhost") != 0) {
if ((hp = gethostbyname(*ahost)) == NULL) {
herror(*ahost);
return(-1);
}
*ahost = hp->h_name;
}
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sp) < 0) {
perror("rcmdsh: socketpair");
return(-1);
}
cpid = fork();
if (cpid < 0) {
perror("rcmdsh: fork failed");
return(-1);
} else if (cpid == 0) {
(void) close(sp[0]);
if (dup2(sp[1], 0) < 0 || dup2(0, 1) < 0) {
perror("rcmdsh: dup2 failed");
_exit(255);
}
cpid = fork();
if (cpid < 0) {
perror("rcmdsh: fork to lose parent failed");
_exit(255);
}
if (cpid > 0)
_exit(0);
if (setuid(pw->pw_uid)) {
(void) fprintf(stderr, "rcmdsh: setuid(%u): %s\n",
pw->pw_uid, strerror(errno));
_exit(255);
}
if (!strcmp(*ahost, "localhost") && !strcmp(locuser, remuser)) {
if (pw->pw_shell[0] == '\0')
rshprog = _PATH_BSHELL;
else
rshprog = pw->pw_shell;
p = strrchr(rshprog, '/');
execlp(rshprog, p ? p+1 : rshprog, "-c", cmd,
(char *) NULL);
} else {
p = strrchr(rshprog, '/');
execlp(rshprog, p ? p+1 : rshprog, *ahost, "-l",
remuser, cmd, (char *) NULL);
}
(void) fprintf(stderr, "rcmdsh: execlp %s failed: %s\n",
rshprog, strerror(errno));
_exit(255);
} else {
(void) close(sp[1]);
(void) wait(NULL);
}
return(sp[0]);
}