/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright (C) 2013 Intel Corporation Authors: Nathaniel Chen 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 . ***/ #include #include #include #include #include #include #include "dirent-util.h" #include "fd-util.h" #include "fileio.h" #include "log.h" #include "macro.h" #include "smack-setup.h" #include "string-util.h" #include "util.h" #ifdef HAVE_SMACK static int write_access2_rules(const char* srcdir) { _cleanup_close_ int load2_fd = -1, change_fd = -1; _cleanup_closedir_ DIR *dir = NULL; struct dirent *entry; char buf[NAME_MAX]; int dfd = -1; int r = 0; load2_fd = open("/sys/fs/smackfs/load2", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); if (load2_fd < 0) { if (errno != ENOENT) log_warning_errno(errno, "Failed to open '/sys/fs/smackfs/load2': %m"); return -errno; /* negative error */ } change_fd = open("/sys/fs/smackfs/change-rule", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); if (change_fd < 0) { if (errno != ENOENT) log_warning_errno(errno, "Failed to open '/sys/fs/smackfs/change-rule': %m"); return -errno; /* negative error */ } /* write rules to load2 or change-rule from every file in the directory */ dir = opendir(srcdir); if (!dir) { if (errno != ENOENT) log_warning_errno(errno, "Failed to opendir '%s': %m", srcdir); return errno; /* positive on purpose */ } dfd = dirfd(dir); assert(dfd >= 0); FOREACH_DIRENT(entry, dir, return 0) { int fd; _cleanup_fclose_ FILE *policy = NULL; if (!dirent_is_file(entry)) continue; fd = openat(dfd, entry->d_name, O_RDONLY|O_CLOEXEC); if (fd < 0) { if (r == 0) r = -errno; log_warning_errno(errno, "Failed to open '%s': %m", entry->d_name); continue; } policy = fdopen(fd, "re"); if (!policy) { if (r == 0) r = -errno; safe_close(fd); log_error_errno(errno, "Failed to open '%s': %m", entry->d_name); continue; } /* load2 write rules in the kernel require a line buffered stream */ FOREACH_LINE(buf, policy, log_error_errno(errno, "Failed to read line from '%s': %m", entry->d_name)) { _cleanup_free_ char *sbj = NULL, *obj = NULL, *acc1 = NULL, *acc2 = NULL; if (isempty(truncate_nl(buf))) continue; /* if 3 args -> load rule : subject object access1 */ /* if 4 args -> change rule : subject object access1 access2 */ if (sscanf(buf, "%ms %ms %ms %ms", &sbj, &obj, &acc1, &acc2) < 3) { log_error_errno(errno, "Failed to parse rule '%s' in '%s', ignoring.", buf, entry->d_name); continue; } if (write(isempty(acc2) ? load2_fd : change_fd, buf, strlen(buf)) < 0) { if (r == 0) r = -errno; log_error_errno(errno, "Failed to write '%s' to '%s' in '%s'", buf, isempty(acc2) ? "/sys/fs/smackfs/load2" : "/sys/fs/smackfs/change-rule", entry->d_name); } } } return r; } static int write_cipso2_rules(const char* srcdir) { _cleanup_close_ int cipso2_fd = -1; _cleanup_closedir_ DIR *dir = NULL; struct dirent *entry; char buf[NAME_MAX]; int dfd = -1; int r = 0; cipso2_fd = open("/sys/fs/smackfs/cipso2", O_RDWR|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); if (cipso2_fd < 0) { if (errno != ENOENT) log_warning_errno(errno, "Failed to open '/sys/fs/smackfs/cipso2': %m"); return -errno; /* negative error */ } /* write rules to cipso2 from every file in the directory */ dir = opendir(srcdir); if (!dir) { if (errno != ENOENT) log_warning_errno(errno, "Failed to opendir '%s': %m", srcdir); return errno; /* positive on purpose */ } dfd = dirfd(dir); assert(dfd >= 0); FOREACH_DIRENT(entry, dir, return 0) { int fd; _cleanup_fclose_ FILE *policy = NULL; if (!dirent_is_file(entry)) continue; fd = openat(dfd, entry->d_name, O_RDONLY|O_CLOEXEC); if (fd < 0) { if (r == 0) r = -errno; log_error_errno(errno, "Failed to open '%s': %m", entry->d_name); continue; } policy = fdopen(fd, "re"); if (!policy) { if (r == 0) r = -errno; safe_close(fd); log_error_errno(errno, "Failed to open '%s': %m", entry->d_name); continue; } /* cipso2 write rules in the kernel require a line buffered stream */ FOREACH_LINE(buf, policy, log_error_errno(errno, "Failed to read line from '%s': %m", entry->d_name)) { if (isempty(truncate_nl(buf))) continue; if (write(cipso2_fd, buf, strlen(buf)) < 0) { if (r == 0) r = -errno; log_error_errno(errno, "Failed to write '%s' to '/sys/fs/smackfs/cipso2' in '%s'", buf, entry->d_name); break; } } } return r; } #endif int mac_smack_setup(bool *loaded_policy) { #ifdef HAVE_SMACK int r; assert(loaded_policy); r = write_access2_rules("/etc/smack/accesses.d/"); switch(r) { case -ENOENT: log_debug("Smack is not enabled in the kernel."); return 0; case ENOENT: log_debug("Smack access rules directory '/etc/smack/accesses.d/' not found"); return 0; case 0: log_info("Successfully loaded Smack policies."); break; default: log_warning_errno(r, "Failed to load Smack access rules, ignoring: %m"); return 0; } #ifdef SMACK_RUN_LABEL r = write_string_file("/proc/self/attr/current", SMACK_RUN_LABEL, 0); if (r) log_warning_errno(r, "Failed to set SMACK label \"%s\" on self: %m", SMACK_RUN_LABEL); #endif r = write_cipso2_rules("/etc/smack/cipso.d/"); switch(r) { case -ENOENT: log_debug("Smack/CIPSO is not enabled in the kernel."); return 0; case ENOENT: log_debug("Smack/CIPSO access rules directory '/etc/smack/cipso.d/' not found"); return 0; case 0: log_info("Successfully loaded Smack/CIPSO policies."); break; default: log_warning_errno(r, "Failed to load Smack/CIPSO access rules, ignoring: %m"); return 0; } *loaded_policy = true; #endif return 0; }