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/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common
* Development and Distribution License("CDDL") (collectively, the
* "License"). You may not use this file except in compliance with the
* License. You can obtain a copy of the License at
* http://www.netbeans.org/cddl-gplv2.html
* or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
* specific language governing permissions and limitations under the
* License. When distributing the software, include this License Header
* Notice in each file and include the License file at
* nbbuild/licenses/CDDL-GPL-2-CP. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the
* License Header, with the fields enclosed by brackets [] replaced by
* your own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Contributor(s):
*
* The Original Software is NetBeans. The Initial Developer of the Original
* Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
* Microsystems, Inc. All Rights Reserved.
*
* If you wish your version of this file to be governed by only the CDDL
* or only the GPL Version 2, indicate your decision by adding
* "[Contributor] elects to include this software in this distribution
* under the [CDDL or GPL Version 2] license." If you do not indicate a
* single choice of license, a recipient has the option to distribute
* your version of this file under either the CDDL, the GPL Version 2 or
* to extend the choice of license to its licensees as provided above.
* However, if you add GPL Version 2 code and therefore, elected the GPL
* Version 2 license, then the option applies only if the new code is
* made subject to such option by the copyright holder.
*/
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#ifdef SOLARIS
#include <stropts.h>
#else
#include <sys/ioctl.h>
#endif
#include <stdio.h>
#include <errno.h>
#define MAX_PASSWORD_LENGTH 64
#define MAX_CMD_LENGTH 256
void usage() {
fprintf(stderr, "Usage: \n");
fprintf(stderr, " ./privp user privs pid\n");
}
/*
* Kind of wrapper for /sbin/su command.
* Usage:
* privp user privs pid
*
* As an argument it takes pid of process that needs to get privileges privs.
* Then it reads password (to pass to /sbin/su) from stdin
*
*/
int main(int argc, char** argv) {
if (argc < 4) {
usage();
exit(1);
}
char readPassword = 1;
/*
* setsid(2) - creates a new session, if the calling process
* is not a process group leader. Upon return the calling process
* will be the session leader of this new session,
* will be the process group leader of a new process group,
* and will have no controlling terminal.
*/
pid_t gid = setsid();
if (gid == -1) {
// The calling process is already a process group leader
// We already have controlling terminal (?)
readPassword = 0;
}
/*
* /dev/ptmx - a character file used to create a pseudo-terminal master
* and slave pair
*/
int master_fd = open("/dev/ptmx", O_RDWR);
if (master_fd == -1) {
fprintf(stderr, "Cannot open /dev/ptmx\n");
perror(NULL);
exit(1);
}
/*
* Before opening the pseudo-terminal slave, you must pass the master's
* file descriptor to grantpt(3) and unlockpt(3).
*/
if (grantpt(master_fd) == -1) {
fprintf(stderr, "grantpt() failed\n");
perror(NULL);
exit(1);
}
if (unlockpt(master_fd) == -1) {
fprintf(stderr, "unlockpt() failed\n");
perror(NULL);
exit(1);
}
char *slave_name = ptsname(master_fd);
if (slave_name == NULL) {
fprintf(stderr, "Cannot get name of slave pseudo-terminal device\n");
perror(NULL);
exit(1);
}
int slave_fd = open(slave_name, O_RDWR);
#if defined (__SVR4) && defined (__sun)
/*
* ptem(7M) - STREAMS Pseudo Terminal Emulation module
* ptem is a STREAMS module that, when used in conjunction with
* a line discipline and pseudo terminal driver, emulates a terminal.
*
* The ptem module must be pushed onto the slave side of a pseudo terminal
* STREAM, before the ldterm(7M) module is pushed.
*
*/
ioctl(slave_fd, I_PUSH, "ptem");
/*
* ldterm(7M) - standard STREAMS terminal line discipline module
*
* The ldterm STREAMS module provides most of the termio(7I)
* terminal interface.
*/
ioctl(slave_fd, I_PUSH, "ldterm");
/*
* Read password from stdin and write it to master_fd ...
*/
#endif
if (readPassword == 1) {
char pwd[MAX_PASSWORD_LENGTH];
int passwdLength = read(STDIN_FILENO, pwd, MAX_PASSWORD_LENGTH);
int result = write(master_fd, pwd, passwdLength);
// Clear password...
memset(pwd, 0, MAX_PASSWORD_LENGTH);
if (result == -1) {
fprintf(stderr, "Cannot redirect pwd\n");
perror(NULL);
exit(1);
}
}
char command[MAX_CMD_LENGTH];
sprintf(command, "/bin/ppriv -s A+%s %s", argv[2], argv[3]);
/*
* exec(2) -
* ...
* The new process also inherits the following attributes from
* the calling process:
* ...
* session membership
* controlling terminal
* ...
*/
execlp("/sbin/su", "-", argv[1], "-c", command, NULL);
return (EXIT_SUCCESS);
}
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