| 1 |
/*
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| 2 |
* sandbox.c
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| 3 |
*
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| 4 |
* Main sandbox related functions.
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| 5 |
*
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| 6 |
* Copyright 1999-2008 Gentoo Foundation
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* Licensed under the GPL-2
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*
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* Some parts might have Copyright:
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*
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* Copyright (C) 2002 Brad House <brad@mainstreetsoftworks.com>
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*/
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| 14 |
#include "headers.h"
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| 15 |
#include "sbutil.h"
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| 16 |
#include "sandbox.h"
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| 17 |
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| 18 |
static int print_debug = 0;
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| 19 |
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| 20 |
volatile static int stop_called = 0;
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| 21 |
volatile static pid_t child_pid = 0;
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| 22 |
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| 23 |
static char log_domain[] = "sandbox";
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| 24 |
static const char sandbox_banner[] = "============================= Gentoo path sandbox ==============================";
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| 26 |
int setup_sandbox(struct sandbox_info_t *sandbox_info, bool interactive)
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| 27 |
{
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| 28 |
if (NULL != getenv(ENV_PORTAGE_TMPDIR)) {
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| 29 |
/* Portage handle setting SANDBOX_WRITE itself. */
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| 30 |
sandbox_info->work_dir[0] = '\0';
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} else {
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| 32 |
if (NULL == getcwd(sandbox_info->work_dir, SB_PATH_MAX)) {
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| 33 |
perror("sandbox: Failed to get current directory");
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return -1;
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}
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if (interactive)
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setenv(ENV_SANDBOX_WORKDIR, sandbox_info->work_dir, 1);
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}
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/* Do not resolve symlinks, etc .. libsandbox will handle that. */
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if (!rc_is_dir(VAR_TMPDIR, true)) {
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perror("sandbox: Failed to get var_tmp_dir");
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return -1;
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}
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snprintf(sandbox_info->var_tmp_dir, SB_PATH_MAX, "%s", VAR_TMPDIR);
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if (-1 == get_tmp_dir(sandbox_info->tmp_dir)) {
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perror("sandbox: Failed to get tmp_dir");
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return -1;
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}
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setenv(ENV_TMPDIR, sandbox_info->tmp_dir, 1);
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sandbox_info->home_dir = getenv("HOME");
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if (!sandbox_info->home_dir) {
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sandbox_info->home_dir = sandbox_info->tmp_dir;
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setenv("HOME", sandbox_info->home_dir, 1);
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}
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/* Generate sandbox lib path */
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get_sandbox_lib(sandbox_info->sandbox_lib);
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/* Generate sandbox bashrc path */
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get_sandbox_rc(sandbox_info->sandbox_rc);
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/* Generate sandbox log full path */
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get_sandbox_log(sandbox_info->sandbox_log);
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if (rc_file_exists(sandbox_info->sandbox_log)) {
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if (-1 == unlink(sandbox_info->sandbox_log)) {
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perror("sandbox: Could not unlink old log file");
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return -1;
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}
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}
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/* Generate sandbox debug log full path */
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get_sandbox_debug_log(sandbox_info->sandbox_debug_log);
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if (rc_file_exists(sandbox_info->sandbox_debug_log)) {
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if (-1 == unlink(sandbox_info->sandbox_debug_log)) {
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perror("sandbox: Could not unlink old debug log file");
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return -1;
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}
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}
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return 0;
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}
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int print_sandbox_log(char *sandbox_log)
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{
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int sandbox_log_file = -1;
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char *beep_count_env = NULL;
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int i, beep_count = 0;
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off_t len = 0;
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char *buffer = NULL;
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if (!rc_is_file(sandbox_log, false)) {
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perror("sandbox: Log file is not a regular file");
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return 0;
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}
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len = rc_get_size(sandbox_log, true);
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if (0 == len)
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return 0;
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sandbox_log_file = sb_open(sandbox_log, O_RDONLY, 0);
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if (-1 == sandbox_log_file) {
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perror("sandbox: Could not open Log file");
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return 0;
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}
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buffer = xmalloc((len + 1) * sizeof(char));
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if (NULL == buffer) {
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perror("sandbox: Could not allocate buffer for Log file");
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return 0;
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}
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memset(buffer, 0, len + 1);
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if (-1 == sb_read(sandbox_log_file, buffer, len)) {
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perror("sandbox: Could read Log file");
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return 0;
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}
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sb_close(sandbox_log_file);
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SB_EERROR(
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"--------------------------- ACCESS VIOLATION SUMMARY ---------------------------",
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"\n");
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SB_EERROR("LOG FILE", " \"%s\"\n\n", sandbox_log);
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fprintf(stderr, "%s", buffer);
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free(buffer);
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SB_EERROR(
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"--------------------------------------------------------------------------------",
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"\n");
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beep_count_env = getenv(ENV_SANDBOX_BEEP);
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if (beep_count_env)
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beep_count = atoi(beep_count_env);
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else
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beep_count = DEFAULT_BEEP_COUNT;
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for (i = 0; i < beep_count; i++) {
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fputc('\a', stderr);
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if (i < beep_count - 1)
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sleep(1);
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}
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return 1;
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}
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void stop(int signum)
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{
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if (0 == stop_called) {
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stop_called = 1;
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printf("sandbox: Caught signal %d in pid %d\n",
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signum, getpid());
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} else {
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fprintf(stderr,
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"sandbox: Signal already caught and busy still cleaning up!\n");
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}
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}
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void usr1_handler(int signum, siginfo_t *siginfo, void *ucontext)
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{
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if (0 == stop_called) {
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stop_called = 1;
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printf("sandbox: Caught signal %d in pid %d\n",
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signum, getpid());
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/* FIXME: This is really bad form, as we should kill the whole process
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* tree, but currently that is too much work and not worth the
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* effort. Thus we only kill the calling process and our child
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* for now.
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*/
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if (siginfo->si_pid > 0)
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kill(siginfo->si_pid, SIGKILL);
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kill(child_pid, SIGKILL);
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} else {
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fprintf(stderr,
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"sandbox: Signal already caught and busy still cleaning up!\n");
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}
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}
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int spawn_shell(char *argv_bash[], char **env, int debug)
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{
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int status = 0;
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int ret = 0;
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child_pid = fork();
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/* Child's process */
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if (0 == child_pid) {
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int ret = execve(argv_bash[0], argv_bash, env);
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perror("sandbox: Failed to exec child");
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_exit(ret);
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} else if (child_pid < 0) {
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if (debug)
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fprintf(stderr, "Process failed to spawn!\n");
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return 0;
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}
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/* fork() creates a copy of this, so no need to use more memory than
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* absolutely needed. */
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str_list_free(argv_bash);
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str_list_free(env);
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ret = waitpid(child_pid, &status, 0);
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if (-1 == ret) {
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perror("sandbox: Failed to waitpid for child");
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return 0;
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} else if (status != 0) {
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if (WIFSIGNALED(status))
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psignal(WTERMSIG(status), "Sandboxed process killed by signal");
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else if (debug)
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fprintf(stderr, "Process returned with failed exit status %d!\n", WEXITSTATUS(status));
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return 0;
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}
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return 1;
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}
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| 217 |
int main(int argc, char **argv)
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{
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struct sigaction act_new;
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int success = 1;
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int sandbox_log_presence = 0;
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struct sandbox_info_t sandbox_info;
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| 226 |
char **sandbox_environ;
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char **argv_bash = NULL;
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char *run_str = "-c";
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rc_log_domain(log_domain);
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/* Only print info if called with no arguments .... */
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if (argc < 2)
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print_debug = 1;
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else {
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/* handle a few common options */
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if (!strcmp(argv[1], "--version") || !strcmp(argv[1], "-V")) {
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puts(
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"Gentoo path sandbox\n"
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" version: " PACKAGE_VERSION "\n"
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" C lib: " LIBC_VERSION "\n"
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" build: " __DATE__ " " __TIME__ "\n"
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" contact: " PACKAGE_BUGREPORT " via http://bugs.gentoo.org/\n"
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" rtld: "
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#ifdef BROKEN_RTLD_NEXT
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"next is broken ;(\n"
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#else
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"next is OK! :D\n"
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#endif
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"\nconfigured with these options:\n"
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SANDBOX_CONFIGURE_OPTS
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);
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return 0;
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} else if (!strcmp(argv[1], "--help") || !strcmp(argv[1], "-h")) {
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puts(
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"Usage: sandbox [program [program args...]]\n"
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"\n"
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"Sandbox will start up a sandbox session and execute the specified program.\n"
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"If no program is specified, an interactive shell is automatically launched.\n"
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"You can use this to quickly test out sandbox behavior.\n"
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"\n"
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"Upon startup, initial settings are taken from these files / directories:\n"
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"\t" SANDBOX_CONF_FILE "\n"
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"\t" SANDBOX_CONFD_DIR "\n"
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| 266 |
"\n"
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| 267 |
"Contact: " PACKAGE_BUGREPORT " via http://bugs.gentoo.org/"
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);
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return 0;
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}
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}
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| 272 |
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| 273 |
if (print_debug)
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| 274 |
puts(sandbox_banner);
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| 275 |
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| 276 |
/* check if a sandbox is already running */
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| 277 |
if (NULL != getenv(ENV_SANDBOX_ACTIVE)) {
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| 278 |
fprintf(stderr, "Not launching a new sandbox instance\n");
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| 279 |
fprintf(stderr, "Another one is already running in this process hierarchy.\n");
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| 280 |
exit(EXIT_FAILURE);
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| 281 |
}
|
| 282 |
|
| 283 |
/* determine the location of all the sandbox support files */
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| 284 |
if (print_debug)
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| 285 |
printf("Detection of the support files.\n");
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| 286 |
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| 287 |
if (-1 == setup_sandbox(&sandbox_info, print_debug)) {
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| 288 |
fprintf(stderr, "sandbox: Failed to setup sandbox.");
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| 289 |
exit(EXIT_FAILURE);
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| 290 |
}
|
| 291 |
|
| 292 |
/* verify the existance of required files */
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| 293 |
if (print_debug)
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| 294 |
printf("Verification of the required files.\n");
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| 295 |
|
| 296 |
if (!rc_file_exists(sandbox_info.sandbox_rc)) {
|
| 297 |
perror("sandbox: Could not open the sandbox rc file");
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| 298 |
exit(EXIT_FAILURE);
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| 299 |
}
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| 300 |
|
| 301 |
/* set up the required environment variables */
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| 302 |
if (print_debug)
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| 303 |
printf("Setting up the required environment variables.\n");
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| 304 |
|
| 305 |
/* If not in portage, cd into it work directory */
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| 306 |
if ('\0' != sandbox_info.work_dir[0])
|
| 307 |
chdir(sandbox_info.work_dir);
|
| 308 |
|
| 309 |
/* Setup the child environment stuff.
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| 310 |
* XXX: We free this in spawn_shell(). */
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| 311 |
sandbox_environ = setup_environ(&sandbox_info, print_debug);
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| 312 |
if (NULL == sandbox_environ)
|
| 313 |
goto oom_error;
|
| 314 |
|
| 315 |
/* Setup bash argv */
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| 316 |
str_list_add_item_copy(argv_bash, "/bin/bash", oom_error);
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| 317 |
str_list_add_item_copy(argv_bash, "-rcfile", oom_error);
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| 318 |
str_list_add_item_copy(argv_bash, sandbox_info.sandbox_rc, oom_error);
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| 319 |
if (argc >= 2) {
|
| 320 |
int i;
|
| 321 |
|
| 322 |
str_list_add_item_copy(argv_bash, run_str, oom_error);
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| 323 |
str_list_add_item_copy(argv_bash, argv[1], oom_error);
|
| 324 |
for (i = 2; i < argc; i++) {
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| 325 |
char *tmp_ptr;
|
| 326 |
|
| 327 |
tmp_ptr = xrealloc(argv_bash[4],
|
| 328 |
(strlen(argv_bash[4]) +
|
| 329 |
strlen(argv[i]) + 2) *
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| 330 |
sizeof(char));
|
| 331 |
if (NULL == tmp_ptr)
|
| 332 |
goto oom_error;
|
| 333 |
argv_bash[4] = tmp_ptr;
|
| 334 |
|
| 335 |
snprintf(argv_bash[4] + strlen(argv_bash[4]),
|
| 336 |
strlen(argv[i]) + 2, " %s",
|
| 337 |
argv[i]);
|
| 338 |
}
|
| 339 |
}
|
| 340 |
|
| 341 |
/* set up the required signal handlers */
|
| 342 |
signal(SIGHUP, &stop);
|
| 343 |
signal(SIGINT, &stop);
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| 344 |
signal(SIGQUIT, &stop);
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| 345 |
signal(SIGTERM, &stop);
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| 346 |
act_new.sa_sigaction = usr1_handler;
|
| 347 |
sigemptyset (&act_new.sa_mask);
|
| 348 |
act_new.sa_flags = SA_SIGINFO | SA_RESTART;
|
| 349 |
sigaction (SIGUSR1, &act_new, NULL);
|
| 350 |
|
| 351 |
/* STARTING PROTECTED ENVIRONMENT */
|
| 352 |
if (print_debug) {
|
| 353 |
printf("The protected environment has been started.\n");
|
| 354 |
printf("--------------------------------------------------------------------------------\n");
|
| 355 |
}
|
| 356 |
|
| 357 |
if (print_debug)
|
| 358 |
printf("Process being started in forked instance.\n");
|
| 359 |
|
| 360 |
/* Start Bash */
|
| 361 |
if (!spawn_shell(argv_bash, sandbox_environ, print_debug))
|
| 362 |
success = 0;
|
| 363 |
|
| 364 |
/* As spawn_shell() free both argv_bash and sandbox_environ, make sure
|
| 365 |
* we do not run into issues in future if we need a OOM error below
|
| 366 |
* this ... */
|
| 367 |
argv_bash = NULL;
|
| 368 |
sandbox_environ = NULL;
|
| 369 |
|
| 370 |
if (print_debug)
|
| 371 |
printf("Cleaning up sandbox process\n");
|
| 372 |
|
| 373 |
if (print_debug) {
|
| 374 |
puts(sandbox_banner);
|
| 375 |
printf("The protected environment has been shut down.\n");
|
| 376 |
}
|
| 377 |
|
| 378 |
if (rc_file_exists(sandbox_info.sandbox_log)) {
|
| 379 |
sandbox_log_presence = 1;
|
| 380 |
print_sandbox_log(sandbox_info.sandbox_log);
|
| 381 |
} else if (print_debug) {
|
| 382 |
printf("--------------------------------------------------------------------------------\n");
|
| 383 |
}
|
| 384 |
|
| 385 |
if ((sandbox_log_presence) || (!success))
|
| 386 |
return 1;
|
| 387 |
else
|
| 388 |
return 0;
|
| 389 |
|
| 390 |
oom_error:
|
| 391 |
if (NULL != argv_bash)
|
| 392 |
str_list_free(argv_bash);
|
| 393 |
|
| 394 |
perror("sandbox: Out of memory (environ)");
|
| 395 |
exit(EXIT_FAILURE);
|
| 396 |
}
|