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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2014 Kay Sievers
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <unistd.h>
#include "base-filesystem.h"
#include "log.h"
#include "macro.h"
#include "util.h"
typedef struct BaseFilesystem {
const char *dir;
mode_t mode;
const char *target;
const char *exists;
} BaseFilesystem;
static const BaseFilesystem table[] = {
{ "bin", 0, "usr/bin\0", NULL },
{ "lib", 0, "usr/lib\0", NULL },
{ "root", 0755, NULL, NULL },
{ "sbin", 0, "usr/sbin\0", NULL },
{ "usr", 0755, NULL, NULL },
{ "var", 0755, NULL, NULL },
{ "etc", 0755, NULL, NULL },
#if defined(__i386__) || defined(__x86_64__)
{ "lib64", 0, "usr/lib/x86_64-linux-gnu\0"
"usr/lib64\0", "ld-linux-x86-64.so.2" },
#endif
};
int base_filesystem_create(const char *root, uid_t uid, gid_t gid) {
_cleanup_close_ int fd = -1;
unsigned i;
int r = 0;
fd = open(root, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW);
if (fd < 0)
return log_error_errno(errno, "Failed to open root file system: %m");
for (i = 0; i < ELEMENTSOF(table); i ++) {
if (faccessat(fd, table[i].dir, F_OK, AT_SYMLINK_NOFOLLOW) >= 0)
continue;
if (table[i].target) {
const char *target = NULL, *s;
/* check if one of the targets exists */
NULSTR_FOREACH(s, table[i].target) {
if (faccessat(fd, s, F_OK, AT_SYMLINK_NOFOLLOW) < 0)
continue;
/* check if a specific file exists at the target path */
if (table[i].exists) {
_cleanup_free_ char *p = NULL;
p = strjoin(s, "/", table[i].exists, NULL);
if (!p)
return log_oom();
if (faccessat(fd, p, F_OK, AT_SYMLINK_NOFOLLOW) < 0)
continue;
}
target = s;
break;
}
if (!target)
continue;
r = symlinkat(target, fd, table[i].dir);
if (r < 0 && errno != EEXIST)
return log_error_errno(errno, "Failed to create symlink at %s/%s: %m", root, table[i].dir);
if (uid != UID_INVALID || gid != UID_INVALID) {
if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0)
return log_error_errno(errno, "Failed to chown symlink at %s/%s: %m", root, table[i].dir);
}
continue;
}
RUN_WITH_UMASK(0000)
r = mkdirat(fd, table[i].dir, table[i].mode);
if (r < 0 && errno != EEXIST)
return log_error_errno(errno, "Failed to create directory at %s/%s: %m", root, table[i].dir);
if (uid != UID_INVALID || gid != UID_INVALID) {
if (fchownat(fd, table[i].dir, uid, gid, AT_SYMLINK_NOFOLLOW) < 0)
return log_error_errno(errno, "Failed to chown directory at %s/%s: %m", root, table[i].dir);
}
}
return 0;
}
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