Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 393 insertions, 0 deletions

diff --git a/src/core/smack-setup.c b/src/core/smack-setup.c
new file mode 100644
index 0000000..7ea902b
--- /dev/null
+++ b/src/core/smack-setup.c
@@ -0,0 +1,393 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+  Copyright © 2013 Intel Corporation
+  Authors:
+        Nathaniel Chen <nathaniel.chen@intel.com>
+***/
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "sd-messages.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"
+
+#if ENABLE_SMACK
+
+static int fdopen_unlocked_at(int dfd, const char *dir, const char *name, int *status, FILE **ret_file) {
+        int fd, r;
+        FILE *f;
+
+        fd = openat(dfd, name, O_RDONLY|O_CLOEXEC);
+        if (fd < 0) {
+                if (*status == 0)
+                        *status = -errno;
+
+                return log_warning_errno(errno, "Failed to open \"%s/%s\": %m", dir, name);
+        }
+
+        r = fdopen_unlocked(fd, "r", &f);
+        if (r < 0) {
+                if (*status == 0)
+                        *status = r;
+
+                safe_close(fd);
+                return log_error_errno(r, "Failed to open \"%s/%s\": %m", dir, name);
+        }
+
+        *ret_file = f;
+        return 0;
+}
+
+static int write_access2_rules(const char *srcdir) {
+        _cleanup_close_ int load2_fd = -EBADF, change_fd = -EBADF;
+        _cleanup_closedir_ DIR *dir = NULL;
+        int dfd = -EBADF, 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) {
+                _cleanup_fclose_ FILE *policy = NULL;
+
+                if (!dirent_is_file(entry))
+                        continue;
+
+                if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0)
+                        continue;
+
+                /* load2 write rules in the kernel require a line buffered stream */
+                for (;;) {
+                        _cleanup_free_ char *buf = NULL, *sbj = NULL, *obj = NULL, *acc1 = NULL, *acc2 = NULL;
+                        int q;
+
+                        q = read_line(policy, NAME_MAX, &buf);
+                        if (q < 0)
+                                return log_error_errno(q, "Failed to read line from '%s': %m", entry->d_name);
+                        if (q == 0)
+                                break;
+
+                        if (isempty(buf) || strchr(COMMENTS, buf[0]))
+                                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': %m",
+                                                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 = -EBADF;
+        _cleanup_closedir_ DIR *dir = NULL;
+        int dfd = -EBADF, 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) {
+                _cleanup_fclose_ FILE *policy = NULL;
+
+                if (!dirent_is_file(entry))
+                        continue;
+
+                if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0)
+                        continue;
+
+                /* cipso2 write rules in the kernel require a line buffered stream */
+                for (;;) {
+                        _cleanup_free_ char *buf = NULL;
+                        int q;
+
+                        q = read_line(policy, NAME_MAX, &buf);
+                        if (q < 0)
+                                return log_error_errno(q, "Failed to read line from '%s': %m", entry->d_name);
+                        if (q == 0)
+                                break;
+
+                        if (isempty(buf) || strchr(COMMENTS, buf[0]))
+                                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': %m",
+                                                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;
+        int dfd = -EBADF, 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) {
+                _cleanup_fclose_ FILE *policy = NULL;
+
+                if (fdopen_unlocked_at(dfd, srcdir, entry->d_name, &r, &policy) < 0)
+                        continue;
+
+                /* load2 write rules in the kernel require a line buffered stream */
+                for (;;) {
+                        _cleanup_free_ char *buf = NULL;
+                        int q;
+
+                        q = read_line(policy, NAME_MAX, &buf);
+                        if (q < 0)
+                                return log_error_errno(q, "Failed to read line from %s: %m", entry->d_name);
+                        if (q == 0)
+                                break;
+
+                        if (!fputs(buf, dst)) {
+                                if (r == 0)
+                                        r = -EINVAL;
+                                log_error_errno(errno, "Failed to write line to /sys/fs/smackfs/netlabel: %m");
+                                break;
+                        }
+                        q = fflush_and_check(dst);
+                        if (q < 0) {
+                                if (r == 0)
+                                        r = q;
+                                log_error_errno(q, "Failed to flush writes to /sys/fs/smackfs/netlabel: %m");
+                                break;
+                        }
+                }
+        }
+
+        return r;
+}
+
+static int write_onlycap_list(void) {
+        _cleanup_close_ int onlycap_fd = -EBADF;
+        _cleanup_free_ char *list = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        size_t len = 0;
+        int r;
+
+        f = fopen("/etc/smack/onlycap", "re");
+        if (!f) {
+                if (errno != ENOENT)
+                        log_warning_errno(errno, "Failed to read '/etc/smack/onlycap': %m");
+
+                return errno == ENOENT ? ENOENT : -errno;
+        }
+
+        for (;;) {
+                _cleanup_free_ char *buf = NULL;
+                size_t l;
+
+                r = read_line(f, LONG_LINE_MAX, &buf);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to read line from /etc/smack/onlycap: %m");
+                if (r == 0)
+                        break;
+
+                if (isempty(buf) || strchr(COMMENTS, *buf))
+                        continue;
+
+                l = strlen(buf);
+                if (!GREEDY_REALLOC(list, len + l + 1))
+                        return log_oom();
+
+                stpcpy(list + len, buf)[0] = ' ';
+                len += l + 1;
+        }
+
+        if (len == 0)
+                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': %m");
+                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': %m", 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;
+        }
+
+#if HAVE_SMACK_RUN_LABEL
+        r = write_string_file("/proc/self/attr/current", SMACK_RUN_LABEL, WRITE_STRING_FILE_DISABLE_BUFFER);
+        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, WRITE_STRING_FILE_DISABLE_BUFFER);
+        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, WRITE_STRING_FILE_DISABLE_BUFFER);
+        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", WRITE_STRING_FILE_DISABLE_BUFFER);
+        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:
+                return log_struct_errno(LOG_EMERG, r,
+                                        LOG_MESSAGE("Failed to write Smack onlycap list: %m"),
+                                        "MESSAGE_ID=" SD_MESSAGE_SMACK_FAILED_WRITE_STR);
+        }
+
+        *loaded_policy = true;
+
+#endif
+
+        return 0;
+}