libsocket/inet/rexec.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

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

#include <sys/types.h>
#include <sys/socket.h>

#include <netinet/in.h>

#include <stdio.h>
#include <netdb.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <libintl.h>

#ifdef SYSV
#define bcopy(a, b, c)  (void) memcpy((b), (a), (c))
#endif

#define MAX_SHORTSTRLEN 6

void _ruserpass(const char *host, char **aname, char **apass);

int rexec(char **ahost, unsigned short rport, const char *name,
    const char *pass, const char *cmd, int *fd2p)
{
        return (rexec_af(ahost, rport, name, pass, cmd, fd2p, AF_INET));
}

int rexec_af(char **ahost, unsigned short rport, const char *name,
    const char *pass, const char *cmd, int *fd2p, int af)
{
    int s, timo = 1, s3;
    char c;
    ushort_t port;
    static char hostname[MAXHOSTNAMELEN];
    int rc;
    struct addrinfo *res;
    struct addrinfo hints;
    char aport[MAX_SHORTSTRLEN];

    if (!(af == AF_INET || af == AF_INET6 || af == AF_UNSPEC)) {
        (void) fprintf(stderr,
            dgettext(TEXT_DOMAIN, "%d: Address family not "
            "supported\n"), af);
        errno = EAFNOSUPPORT;
        return (-1);
    }
    memset(&hints, 0, sizeof (hints));
    (void) snprintf(aport, MAX_SHORTSTRLEN, "%u", ntohs(rport));
    hints.ai_flags = AI_CANONNAME|AI_ADDRCONFIG|AI_V4MAPPED;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_family = af;
    rc = getaddrinfo(*ahost, aport, &hints, &res);

    if (rc != 0) {
        (void) fprintf(stderr,
            dgettext(TEXT_DOMAIN, "%s: unknown host\n"),
            *ahost);
        return (-1);
    }
    (void) strlcpy(hostname, res->ai_canonname, MAXHOSTNAMELEN);
    *ahost = hostname;
    _ruserpass(res->ai_canonname, (char **)&name, (char **)&pass);
retry:
    s = socket(res->ai_addr->sa_family, res->ai_socktype, res->ai_protocol);
    if (s < 0) {
        perror("rexec: socket");
        freeaddrinfo(res);
        return (-1);
    }
    if (connect(s, res->ai_addr, res->ai_addrlen) != 0) {
        if (errno == ECONNREFUSED && timo <= 16) {
            (void) close(s);
            (void) sleep(timo);
            timo *= 2;
            goto retry;
        }
        perror(*ahost);
        (void) close(s);
        freeaddrinfo(res);
        return (-1);
    }
    if (fd2p == 0) {
        (void) write(s, "", 1);
        port = 0;
    } else {
        int s2;
        socklen_t sin2len;
        struct sockaddr_storage sin2, from;

        s2 = socket(res->ai_family, SOCK_STREAM, 0);
        if (s2 < 0) {
            (void) close(s);
            freeaddrinfo(res);
            return (-1);
        }
        (void) listen(s2, 1);
        sin2len = (socklen_t)sizeof (sin2);
        if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0) {
            perror("getsockname");
            (void) close(s2);
            goto bad;
        }
        if (res->ai_family == AF_INET6) {
            port = ntohs(((struct sockaddr_in6 *)&sin2)->sin6_port);
        } else {
            port = ntohs(((struct sockaddr_in *)&sin2)->sin_port);
        }
        (void) snprintf(aport, MAX_SHORTSTRLEN, "%u", port);
        (void) write(s, aport, strlen(aport)+1);
        {
            socklen_t len = (socklen_t)sizeof (from);
            s3 = accept(s2, (struct sockaddr *)&from, &len);
            (void) close(s2);
            if (s3 < 0) {
                perror("accept");
                port = 0;
                goto bad;
            }
        }
        *fd2p = s3;
    }
    (void) write(s, name, strlen(name) + 1);
    /* should public key encypt the password here */
    (void) write(s, pass, strlen(pass) + 1);
    (void) write(s, cmd, strlen(cmd) + 1);
    if (read(s, &c, 1) != 1) {
        perror(*ahost);
        goto bad;
    }
    if (c != 0) {
        while (read(s, &c, 1) == 1) {
            (void) write(2, &c, 1);
            if (c == '\n')
                break;
        }
        goto bad;
    }
    freeaddrinfo(res);
    return (s);
bad:
    if (port)
        (void) close(*fd2p);
    (void) close(s);
    freeaddrinfo(res);
    return (-1);
}