diff options
Diffstat (limited to 'modules/pam_selinux/pam_selinux_check.c')
| -rw-r--r-- | modules/pam_selinux/pam_selinux_check.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/modules/pam_selinux/pam_selinux_check.c b/modules/pam_selinux/pam_selinux_check.c new file mode 100644 index 0000000..30526d3 --- /dev/null +++ b/modules/pam_selinux/pam_selinux_check.c @@ -0,0 +1,161 @@ +/****************************************************************************** + * A module for Linux-PAM that will set the default security context after login + * via PAM. + * + * Copyright (c) 2003 Red Hat, Inc. + * Written by Dan Walsh <dwalsh@redhat.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, and the entire permission notice in its entirety, + * including the disclaimer of warranties. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * ALTERNATIVELY, this product may be distributed under the terms of + * the GNU Public License, in which case the provisions of the GPL are + * required INSTEAD OF the above restrictions. (This clause is + * necessary due to a potential bad interaction between the GPL and + * the restrictions contained in a BSD-style copyright.) + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +/************************************************************************ + * + * All PAM code goes in this section. + * + ************************************************************************/ + +#include "config.h" + +#include <errno.h> +#include <syslog.h> +#include <unistd.h> /* for getuid(), exit(), getopt() */ +#include <signal.h> +#include <sys/wait.h> /* for wait() */ + +#include <security/pam_appl.h> /* for PAM functions */ +#include <security/pam_misc.h> /* for misc_conv PAM utility function */ + +#define SERVICE_NAME "pam_selinux_check" /* the name of this program for PAM */ + /* The file containing the context to run + * the scripts under. */ +int authenticate_via_pam( const char *user , pam_handle_t **pamh); + +/* authenticate_via_pam() + * + * in: user + * out: nothing + * return: value condition + * ----- --------- + * 1 pam thinks that the user authenticated themselves properly + * 0 otherwise + * + * this function uses pam to authenticate the user running this + * program. this is the only function in this program that makes pam + * calls. + * + */ + +int authenticate_via_pam( const char *user , pam_handle_t **pamh) { + + struct pam_conv *conv; + int result = 0; /* our result, set to 0 (not authenticated) by default */ + + /* this is a jump table of functions for pam to use when it wants to * + * communicate with the user. we'll be using misc_conv(), which is * + * provided for us via pam_misc.h. */ + struct pam_conv pam_conversation = { + misc_conv, + NULL + }; + conv = &pam_conversation; + + + /* make `p_pam_handle' a valid pam handle so we can use it when * + * calling pam functions. */ + if( PAM_SUCCESS != pam_start( SERVICE_NAME, + user, + conv, + pamh ) ) { + fprintf( stderr, _("failed to initialize PAM\n") ); + exit( -1 ); + } + + if( PAM_SUCCESS != pam_set_item(*pamh, PAM_RUSER, user)) + { + fprintf( stderr, _("failed to pam_set_item()\n") ); + exit( -1 ); + } + + /* Ask PAM to authenticate the user running this program */ + if( PAM_SUCCESS == pam_authenticate(*pamh,0) ) { + if ( PAM_SUCCESS == pam_open_session(*pamh, 0) ) + result = 1; /* user authenticated OK! */ + } + return( result ); + +} /* authenticate_via_pam() */ + +int +main (int argc, char **argv) +{ + pam_handle_t *pamh; + int childPid; + + if (argc < 1) + exit (-1); + + if (!authenticate_via_pam(argv[1],&pamh)) + exit(-1); + + childPid = fork(); + if (childPid < 0) { + /* error in fork() */ + fprintf(stderr, _("login: failure forking: %m")); + pam_close_session(pamh, 0); + /* We're done with PAM. Free `pam_handle'. */ + pam_end( pamh, PAM_SUCCESS ); + exit(0); + } + if (childPid) { + close(0); close(1); close(2); + struct sigaction sa; + memset(&sa,0,sizeof(sa)); + sa.sa_handler = SIG_IGN; + sigaction(SIGQUIT, &sa, NULL); + sigaction(SIGINT, &sa, NULL); + while(wait(NULL) == -1 && errno == EINTR) /**/ ; + openlog("login", LOG_ODELAY, LOG_AUTHPRIV); + pam_close_session(pamh, 0); + /* We're done with PAM. Free `pam_handle'. */ + pam_end( pamh, PAM_SUCCESS ); + exit(0); + } + argv[0]=strdup ("/bin/sh"); + argv[1]=NULL; + + /* NOTE: The environment has not been sanitized. LD_PRELOAD and other fun + * things could be set. */ + execv("/bin/sh",argv); + fprintf(stderr,"Failure\n"); + return 0; +} |