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/*
Copyright (c) 2004 Conectiva, Inc.
Copyright (c) 2009 Canonical, Ltd.
Written by Gustavo Niemeyer <niemeyer@conectiva.com>,
Free Ekanayaka <free.ekanayaka@canonical.com>
This file is part of Smart Package Manager.
Smart Package Manager is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 2 of the License, or (at
your option) any later version.
Smart Package Manager is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with Smart Package Manager; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#define _GNU_SOURCE
#include <sys/resource.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <grp.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <pwd.h>
int main(int argc, char *argv[], char *envp[])
{
char *smart_argv[] = {"/usr/share/smart/smart", "update", NULL, NULL};
char *smart_envp[] = {"PATH=/bin:/usr/bin", NULL, NULL};
// Set the HOME environment variable
struct passwd *pwd = getpwuid(geteuid());
if (!pwd) {
fprintf(stderr, "error: Unable to find passwd entry for uid %d (%s)\n",
geteuid(), strerror(errno));
exit(1);
}
if (asprintf(&smart_envp[1], "HOME=%s", pwd->pw_dir) == -1) {
perror("error: Unable to create HOME environment variable");
exit(1);
}
// Handle the --after command line option
if (argc != 1) {
if (argc != 3 || strcmp(argv[1], "--after") != 0) {
fprintf(stderr, "error: Unsupported command line option\n");
exit(1);
}
char *end;
long interval = strtol(argv[2], &end, 10);
if (end == argv[2]) {
fprintf(stderr, "error: Interval value '%s' not a number\n", argv[2]);
exit(1);
}
if (asprintf(&smart_argv[2], "--after=%ld", interval) == -1) {
perror("error: Unable to create argument variable");
exit(1);
}
}
// Drop any supplementary group
if (setgroups(0, NULL) == -1) {
perror("error: Unable to set supplementary groups IDs");
exit(1);
}
// Set real/effective gid and uid
if (setregid(pwd->pw_gid, pwd->pw_gid) == -1) {
fprintf(stderr, "error: Unable to set real and effective gid (%s)\n",
strerror(errno));
exit(1);
}
if (setreuid(pwd->pw_uid, pwd->pw_uid) == -1) {
perror("error: Unable to set real and effective uid");
exit(1);
}
// Close all file descriptors except the standard ones
struct rlimit rlp;
if (getrlimit(RLIMIT_NOFILE, &rlp) == -1) {
perror("error: Unable to determine file descriptor limits");
exit(1);
}
int file_max;
if (rlp.rlim_max == RLIM_INFINITY || rlp.rlim_max > 4096)
file_max = 4096;
else
file_max = rlp.rlim_max;
int file;
for (file = 3; file < file_max; file++) {
close(file);
}
// Set umask to 022
umask(S_IWGRP | S_IWOTH);
if (chdir("/") == -1) {
perror("error: Unable to change working directory");
exit(1);
}
// Run smart update
execve(smart_argv[0], smart_argv, smart_envp);
perror("error: Unable to execute smart");
return 1;
}
/* vim:ts=4:sw=4:et
*/
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