1130b656e5
This will make a number of things easier in the future, as well as (finally!) avoiding the Id-smashing problem which has plagued developers for so long. Boy, I'm glad we're not using sup anymore. This update would have been insane otherwise.
125 lines
2.6 KiB
C
125 lines
2.6 KiB
C
|
|
/*
|
|
* This is an rcmd() replacement originally by
|
|
* Chris Siebenmann <cks@utcc.utoronto.ca>.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char RCSid[] =
|
|
"$FreeBSD$";
|
|
#endif
|
|
|
|
#include "defs.h"
|
|
|
|
#if !defined(DIRECT_RCMD)
|
|
|
|
#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 <unistd.h>
|
|
#include <stdlib.h>
|
|
|
|
static char *
|
|
xbasename(s)
|
|
char *s;
|
|
{
|
|
char *ret;
|
|
|
|
ret = strrchr(s, '/');
|
|
if (ret && ret[1])
|
|
return (ret + 1);
|
|
return s;
|
|
}
|
|
|
|
|
|
/*
|
|
* This is a replacement rcmd() function that uses the rsh(1c)
|
|
* program in place of a direct rcmd() function call so as to
|
|
* avoid having to be root.
|
|
*/
|
|
int
|
|
rshrcmd(ahost, port, luser, ruser, cmd, fd2p)
|
|
char **ahost;
|
|
u_short port;
|
|
char *luser, *ruser, *cmd;
|
|
int *fd2p;
|
|
{
|
|
int cpid;
|
|
struct hostent *hp;
|
|
int sp[2];
|
|
|
|
/* insure that we are indeed being used as we thought. */
|
|
if (fd2p != 0)
|
|
return -1;
|
|
/* validate remote hostname. */
|
|
hp = gethostbyname(*ahost);
|
|
if (hp == 0) {
|
|
error("%s: unknown host", *ahost);
|
|
return -1;
|
|
}
|
|
/* *ahost = hp->h_name; *//* This makes me nervous. */
|
|
|
|
/* get a socketpair we'll use for stdin and stdout. */
|
|
if (socketpair(AF_UNIX, SOCK_STREAM, 0, sp) < 0) {
|
|
error("socketpair(AF_UNIX, SOCK_STREAM, 0) failed: %s.",
|
|
strerror(errno));
|
|
return -1;
|
|
}
|
|
|
|
cpid = fork();
|
|
if (cpid < 0) {
|
|
error("fork failed: %s.", strerror(errno));
|
|
return -1; /* error. */
|
|
}
|
|
if (cpid == 0) {
|
|
/* child. we use sp[1] to be stdin/stdout, and close
|
|
sp[0]. */
|
|
(void) close(sp[0]);
|
|
if (dup2(sp[1], 0) < 0 || dup2(0,1) < 0) {
|
|
error("dup2 failed: %s.", strerror(errno));
|
|
_exit(255);
|
|
}
|
|
/* fork again to lose parent. */
|
|
cpid = fork();
|
|
if (cpid < 0) {
|
|
error("fork to lose parent failed: %s.", strerror(errno));
|
|
_exit(255);
|
|
}
|
|
if (cpid > 0)
|
|
_exit(0);
|
|
/* in grandchild here. */
|
|
|
|
/*
|
|
* If we are rdist'ing to "localhost" as the same user
|
|
* as we are, then avoid running remote shell for efficiency.
|
|
*/
|
|
if (strcmp(*ahost, "localhost") == 0 &&
|
|
strcmp(luser, ruser) == 0) {
|
|
execlp(_PATH_BSHELL, xbasename(_PATH_BSHELL), "-c",
|
|
cmd, (char *) NULL);
|
|
error("execlp %s failed: %s.", _PATH_BSHELL, strerror(errno));
|
|
} else {
|
|
execlp(path_rsh, xbasename(path_rsh),
|
|
*ahost, "-l", ruser, cmd, (char *) NULL);
|
|
error("execlp %s failed: %s.", path_rsh,
|
|
strerror(errno));
|
|
}
|
|
_exit(255);
|
|
}
|
|
if (cpid > 0) {
|
|
/* parent. close sp[1], return sp[0]. */
|
|
(void) close(sp[1]);
|
|
/* reap child. */
|
|
(void) wait(0);
|
|
return sp[0];
|
|
}
|
|
/*NOTREACHED*/
|
|
return (-1);
|
|
}
|
|
|
|
#endif /* !DIRECT_RCMD */
|