cmd/rexd/under.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 * Copyright 1985 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"


/*
 *  under.c - program to execute a command under a given directory
 *
 */

#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <rpc/rpc.h>
#include <nfs/nfs.h>
#include <rpcsvc/mount.h>
#include <sys/time.h>

static char **Argv;     /* saved argument vector (for ps) */
static char *LastArgv;      /* saved end-of-argument vector */

int Debug = 0;

int child = 0;          /* pid of the executed process */
int ChildDied = 0;      /* true when above is valid */
int HasHelper = 0;      /* must kill helpers (interactive mode) */
time_t time_now;
/*
 *  SETPROCTITLE -- set the title of this process for "ps"
 *
 *  Does nothing if there were not enough arguments on the command
 *  line for the information.
 *
 *  Side Effects:
 *      Clobbers argv[] of our main procedure.
 */
void
setproctitle(user, host)
    char *user, *host;
{
    register char *tohere;

    tohere = Argv[0];
    if ((int)(LastArgv == (char *)NULL) ||
            (int)(strlen(user)+strlen(host)+3) > (int)(LastArgv - tohere))
        return;
    *tohere++ = '-';        /* So ps prints (rpc.rexd)  */
    sprintf(tohere, "%s@%s", user, host);
    while (*tohere++)       /* Skip to end of printf output */
        ;
    while (tohere < LastArgv)   /* Avoid confusing ps       */
        *tohere++ = ' ';
}


void
main(argc, argv)
    int argc;
    char **argv;
{
    static char usage[] = "Usage: under [-d] dir command...\n";
    char *dir, *p;
    char hostname[255];
    char *tmpdir, *subdir, *parsefs();
    char dirbuf[1024];
    char error[1024];
    int status;
    int len;

    if (argc < 3)
    {
        fprintf(stderr, usage);
        exit(1);
    }

    /*
     * argv start and extent for setproctitle()
     */
    Argv = argv;
    if (argc > 0)
        LastArgv = argv[argc-1] + strlen(argv[argc-1]);
    else
        LastArgv = NULL;

    gethostname(hostname, 255);
    strcat(hostname, ":/");
    len = strlen(hostname);
    if ( strcmp( argv[1], "-d" ) == 0 )
    {
        Debug = 1;
        argv++;
    }
    dir = argv[1];
    if ( (int)strlen(dir) > len &&  (int)strncmp(dir, hostname, len) == 0)
        dir = strchr(dir, ':') + 1;
    else if (p = strchr(dir, ':'))
    {
        if (p[1] != '/')
        {
            fprintf(stderr, "under: %s invalid name\n", dir);
            exit(1);
        }

        tmpdir = mktemp("/tmp/underXXXXXX");

                if ( Debug && errno )
        {
            if ( errno != ENOENT )
                        printf("mktemp of %s returned %d %s\n",
                                        tmpdir, errno, strerror(errno));
        }
        errno = 0;  /* XXX access() call in mktemp sets errno = ENOENT */

        if (mkdir(tmpdir, 0777))
        {
            perror(tmpdir);
            exit(1);
        }

                if ( Debug && errno )
                        printf("mkdir of %s returned %d %s\n",
                                        tmpdir, errno, strerror(errno));

        subdir = parsefs(dir, error);
        if (subdir == NULL)
        {
            exit(1);
        }
        time_now = time((long *) 0);
        if (mount_nfs(dir, tmpdir, error))
        {
            exit(1);
        }
        strcpy(dirbuf, tmpdir);
        strcat(dirbuf, "/");
        strcat(dirbuf, subdir);
        status = runcmd(dirbuf, argv[2], &argv[2]);
        if (umount_nfs(dir, tmpdir))
            fprintf(stderr, "under: couldn't umount %s\n", dir);
        rmdir(tmpdir);
        exit(status);
    }

    setgid(getgid());
    setuid(getuid());
    if (chdir(dir))
    {
        perror(dir);
        exit(1);
    }
    execvp(argv[2], &argv[2]);
    perror(argv[2]);
    exit(1);
    /* NOTREACHED */
}

typedef void (*sig_t)();

int
runcmd(dir, cmd, args)
    char    *dir;
    char    *cmd;
    char    **args;
{
    int pid, child, status;
    sig_t sigint, sigquit;

    sigint = sigset(SIGINT, SIG_IGN);
    sigquit = sigset(SIGQUIT, SIG_IGN);
    pid = fork();
    if (pid == -1)
        return (0177);
    if (pid == 0)
    {
        setgid(getgid());
        setuid(getuid());
        if (chdir(dir))
        {
            perror(dir);
            exit(1);
        }
        (void) sigset(SIGINT, sigint);
        (void) sigset(SIGQUIT, sigquit);
        execvp(cmd, args);
        perror(cmd);
        exit(1);
    }
    while ((child = wait(&status)) != pid && child != -1)
        ;
    (void) sigset(SIGINT, sigint);
    (void) sigset(SIGQUIT, sigquit);
    if (child == -1)
        return (0177);
    if (status & 0377)
        return (status & 0377);
    return ((status >> 8) & 0377);
}