| /*** |
| This file is part of systemd. |
| |
| Copyright (C) 2013 Intel Corporation |
| Authors: |
| Nathaniel Chen <nathaniel.chen@intel.com> |
| |
| 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 <dirent.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "alloc-util.h" |
| #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" |
| |
| #if ENABLE_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; |
| } |
| |
| static int write_netlabel_rules(const char* srcdir) { |
| _cleanup_fclose_ FILE *dst = NULL; |
| _cleanup_closedir_ DIR *dir = NULL; |
| struct dirent *entry; |
| char buf[NAME_MAX]; |
| int dfd = -1; |
| int r = 0; |
| |
| dst = fopen("/sys/fs/smackfs/netlabel", "we"); |
| if (!dst) { |
| if (errno != ENOENT) |
| log_warning_errno(errno, "Failed to open /sys/fs/smackfs/netlabel: %m"); |
| return -errno; /* negative error */ |
| } |
| |
| /* write rules to dst 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; |
| |
| 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)) { |
| if (!fputs_unlocked(buf, dst)) { |
| if (r == 0) |
| r = -EINVAL; |
| log_error_errno(errno, "Failed to write line to /sys/fs/smackfs/netlabel"); |
| break; |
| } |
| if (fflush(dst)) { |
| if (r == 0) |
| r = -errno; |
| log_error_errno(errno, "Failed to flush writes to /sys/fs/smackfs/netlabel: %m"); |
| break; |
| } |
| } |
| } |
| |
| return r; |
| } |
| |
| static int write_onlycap_list(void) { |
| _cleanup_close_ int onlycap_fd = -1; |
| _cleanup_free_ char *list = NULL; |
| _cleanup_fclose_ FILE *f = NULL; |
| size_t len = 0, allocated = 0; |
| char buf[LINE_MAX]; |
| int r; |
| |
| f = fopen("/etc/smack/onlycap", "re"); |
| if (!f) { |
| if (errno != ENOENT) |
| log_warning_errno(errno, "Failed to read '/etc/smack/onlycap'"); |
| return errno == ENOENT ? ENOENT : -errno; |
| } |
| |
| FOREACH_LINE(buf, f, return -errno) { |
| size_t l; |
| |
| if (isempty(truncate_nl(buf)) || strchr(COMMENTS, *buf)) |
| continue; |
| |
| l = strlen(buf); |
| if (!GREEDY_REALLOC(list, allocated, len + l + 1)) |
| return log_oom(); |
| |
| stpcpy(list + len, buf)[0] = ' '; |
| len += l + 1; |
| } |
| |
| if (!len) |
| return 0; |
| |
| list[len - 1] = 0; |
| |
| onlycap_fd = open("/sys/fs/smackfs/onlycap", O_WRONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY); |
| if (onlycap_fd < 0) { |
| if (errno != ENOENT) |
| log_warning_errno(errno, "Failed to open '/sys/fs/smackfs/onlycap'"); |
| return -errno; /* negative error */ |
| } |
| |
| r = write(onlycap_fd, list, len); |
| if (r < 0) |
| return log_error_errno(errno, "Failed to write onlycap list(%s) to '/sys/fs/smackfs/onlycap'", list); |
| |
| return 0; |
| } |
| |
| #endif |
| |
| int mac_smack_setup(bool *loaded_policy) { |
| |
| #if ENABLE_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 < 0) |
| log_warning_errno(r, "Failed to set SMACK label \"" SMACK_RUN_LABEL "\" on self: %m"); |
| r = write_string_file("/sys/fs/smackfs/ambient", SMACK_RUN_LABEL, 0); |
| if (r < 0) |
| log_warning_errno(r, "Failed to set SMACK ambient label \"" SMACK_RUN_LABEL "\": %m"); |
| r = write_string_file("/sys/fs/smackfs/netlabel", |
| "0.0.0.0/0 " SMACK_RUN_LABEL, 0); |
| if (r < 0) |
| log_warning_errno(r, "Failed to set SMACK netlabel rule \"0.0.0.0/0 " SMACK_RUN_LABEL "\": %m"); |
| r = write_string_file("/sys/fs/smackfs/netlabel", "127.0.0.1 -CIPSO", 0); |
| if (r < 0) |
| log_warning_errno(r, "Failed to set SMACK netlabel rule \"127.0.0.1 -CIPSO\": %m"); |
| #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"); |
| break; |
| case 0: |
| log_info("Successfully loaded Smack/CIPSO policies."); |
| break; |
| default: |
| log_warning_errno(r, "Failed to load Smack/CIPSO access rules, ignoring: %m"); |
| break; |
| } |
| |
| r = write_netlabel_rules("/etc/smack/netlabel.d/"); |
| switch(r) { |
| case -ENOENT: |
| log_debug("Smack/CIPSO is not enabled in the kernel."); |
| return 0; |
| case ENOENT: |
| log_debug("Smack network host rules directory '/etc/smack/netlabel.d/' not found"); |
| break; |
| case 0: |
| log_info("Successfully loaded Smack network host rules."); |
| break; |
| default: |
| log_warning_errno(r, "Failed to load Smack network host rules: %m, ignoring."); |
| break; |
| } |
| |
| r = write_onlycap_list(); |
| switch(r) { |
| case -ENOENT: |
| log_debug("Smack is not enabled in the kernel."); |
| break; |
| case ENOENT: |
| log_debug("Smack onlycap list file '/etc/smack/onlycap' not found"); |
| break; |
| case 0: |
| log_info("Successfully wrote Smack onlycap list."); |
| break; |
| default: |
| log_emergency_errno(r, "Failed to write Smack onlycap list."); |
| return r; |
| } |
| |
| *loaded_policy = true; |
| |
| #endif |
| |
| return 0; |
| } |