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-rw-r--r--src/shared/condition.c529
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diff --git a/src/shared/condition.c b/src/shared/condition.c
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+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+
+ 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 <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/statvfs.h>
+#include <fnmatch.h>
+
+#include "sd-id128.h"
+#include "util.h"
+#include "virt.h"
+#include "path-util.h"
+#include "fileio.h"
+#include "unit.h"
+#include "architecture.h"
+#include "virt.h"
+#include "smack-util.h"
+#include "apparmor-util.h"
+#include "ima-util.h"
+#include "selinux-util.h"
+#include "audit.h"
+#include "condition.h"
+
+Condition* condition_new(ConditionType type, const char *parameter, bool trigger, bool negate) {
+ Condition *c;
+ int r;
+
+ assert(type >= 0);
+ assert(type < _CONDITION_TYPE_MAX);
+ assert(!parameter == (type == CONDITION_NULL));
+
+ c = new0(Condition, 1);
+ if (!c)
+ return NULL;
+
+ c->type = type;
+ c->trigger = trigger;
+ c->negate = negate;
+
+ r = free_and_strdup(&c->parameter, parameter);
+ if (r < 0) {
+ free(c);
+ return NULL;
+ }
+
+ return c;
+}
+
+void condition_free(Condition *c) {
+ assert(c);
+
+ free(c->parameter);
+ free(c);
+}
+
+void condition_free_list(Condition *first) {
+ Condition *c, *n;
+
+ LIST_FOREACH_SAFE(conditions, c, n, first)
+ condition_free(c);
+}
+
+static int condition_test_kernel_command_line(Condition *c) {
+ _cleanup_free_ char *line = NULL;
+ const char *p;
+ bool equal;
+ int r;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_KERNEL_COMMAND_LINE);
+
+ r = proc_cmdline(&line);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return false;
+
+ equal = !!strchr(c->parameter, '=');
+ p = line;
+
+ for (;;) {
+ _cleanup_free_ char *word = NULL;
+ bool found;
+
+ r = unquote_first_word(&p, &word);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ if (equal)
+ found = streq(word, c->parameter);
+ else {
+ const char *f;
+
+ f = startswith(word, c->parameter);
+ found = f && (*f == '=' || *f == 0);
+ }
+
+ if (found)
+ return true;
+ }
+
+ return false;
+}
+
+static int condition_test_virtualization(Condition *c) {
+ int b, v;
+ const char *id;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_VIRTUALIZATION);
+
+ v = detect_virtualization(&id);
+ if (v < 0)
+ return v;
+
+ /* First, compare with yes/no */
+ b = parse_boolean(c->parameter);
+
+ if (v > 0 && b > 0)
+ return true;
+
+ if (v == 0 && b == 0)
+ return true;
+
+ /* Then, compare categorization */
+ if (v == VIRTUALIZATION_VM && streq(c->parameter, "vm"))
+ return true;
+
+ if (v == VIRTUALIZATION_CONTAINER && streq(c->parameter, "container"))
+ return true;
+
+ /* Finally compare id */
+ return v > 0 && streq(c->parameter, id);
+}
+
+static int condition_test_architecture(Condition *c) {
+ int a, b;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_ARCHITECTURE);
+
+ a = uname_architecture();
+ if (a < 0)
+ return a;
+
+ if (streq(c->parameter, "native"))
+ b = native_architecture();
+ else
+ b = architecture_from_string(c->parameter);
+ if (b < 0)
+ return b;
+
+ return a == b;
+}
+
+static int condition_test_host(Condition *c) {
+ _cleanup_free_ char *h = NULL;
+ sd_id128_t x, y;
+ int r;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_HOST);
+
+ if (sd_id128_from_string(c->parameter, &x) >= 0) {
+
+ r = sd_id128_get_machine(&y);
+ if (r < 0)
+ return r;
+
+ return sd_id128_equal(x, y);
+ }
+
+ h = gethostname_malloc();
+ if (!h)
+ return -ENOMEM;
+
+ return fnmatch(c->parameter, h, FNM_CASEFOLD) == 0;
+}
+
+static int condition_test_ac_power(Condition *c) {
+ int r;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_AC_POWER);
+
+ r = parse_boolean(c->parameter);
+ if (r < 0)
+ return r;
+
+ return (on_ac_power() != 0) == !!r;
+}
+
+static int condition_test_security(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_SECURITY);
+
+ if (streq(c->parameter, "selinux"))
+ return mac_selinux_use();
+ if (streq(c->parameter, "smack"))
+ return mac_smack_use();
+ if (streq(c->parameter, "apparmor"))
+ return mac_apparmor_use();
+ if (streq(c->parameter, "audit"))
+ return use_audit();
+ if (streq(c->parameter, "ima"))
+ return use_ima();
+
+ return false;
+}
+
+static int condition_test_capability(Condition *c) {
+ _cleanup_fclose_ FILE *f = NULL;
+ cap_value_t value;
+ char line[LINE_MAX];
+ unsigned long long capabilities = -1;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_CAPABILITY);
+
+ /* If it's an invalid capability, we don't have it */
+
+ if (cap_from_name(c->parameter, &value) < 0)
+ return -EINVAL;
+
+ /* If it's a valid capability we default to assume
+ * that we have it */
+
+ f = fopen("/proc/self/status", "re");
+ if (!f)
+ return -errno;
+
+ while (fgets(line, sizeof(line), f)) {
+ truncate_nl(line);
+
+ if (startswith(line, "CapBnd:")) {
+ (void) sscanf(line+7, "%llx", &capabilities);
+ break;
+ }
+ }
+
+ return !!(capabilities & (1ULL << value));
+}
+
+static int condition_test_needs_update(Condition *c) {
+ const char *p;
+ struct stat usr, other;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_NEEDS_UPDATE);
+
+ /* If the file system is read-only we shouldn't suggest an update */
+ if (path_is_read_only_fs(c->parameter) > 0)
+ return false;
+
+ /* Any other failure means we should allow the condition to be true,
+ * so that we rather invoke too many update tools then too
+ * few. */
+
+ if (!path_is_absolute(c->parameter))
+ return true;
+
+ p = strappenda(c->parameter, "/.updated");
+ if (lstat(p, &other) < 0)
+ return true;
+
+ if (lstat("/usr/", &usr) < 0)
+ return true;
+
+ return usr.st_mtim.tv_sec > other.st_mtim.tv_sec ||
+ (usr.st_mtim.tv_sec == other.st_mtim.tv_sec && usr.st_mtim.tv_nsec > other.st_mtim.tv_nsec);
+}
+
+static int condition_test_first_boot(Condition *c) {
+ int r;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_FIRST_BOOT);
+
+ r = parse_boolean(c->parameter);
+ if (r < 0)
+ return r;
+
+ return (access("/run/systemd/first-boot", F_OK) >= 0) == !!r;
+}
+
+static int condition_test_path_exists(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_EXISTS);
+
+ return access(c->parameter, F_OK) >= 0;
+}
+
+static int condition_test_path_exists_glob(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_EXISTS_GLOB);
+
+ return glob_exists(c->parameter) > 0;
+}
+
+static int condition_test_path_is_directory(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_IS_DIRECTORY);
+
+ return is_dir(c->parameter, true) > 0;
+}
+
+static int condition_test_path_is_symbolic_link(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_IS_SYMBOLIC_LINK);
+
+ return is_symlink(c->parameter) > 0;
+}
+
+static int condition_test_path_is_mount_point(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_IS_MOUNT_POINT);
+
+ return path_is_mount_point(c->parameter, true) > 0;
+}
+
+static int condition_test_path_is_read_write(Condition *c) {
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_PATH_IS_READ_WRITE);
+
+ return path_is_read_only_fs(c->parameter) <= 0;
+}
+
+static int condition_test_directory_not_empty(Condition *c) {
+ int r;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_DIRECTORY_NOT_EMPTY);
+
+ r = dir_is_empty(c->parameter);
+ return r <= 0 && r != -ENOENT;
+}
+
+static int condition_test_file_not_empty(Condition *c) {
+ struct stat st;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_FILE_NOT_EMPTY);
+
+ return (stat(c->parameter, &st) >= 0 &&
+ S_ISREG(st.st_mode) &&
+ st.st_size > 0);
+}
+
+static int condition_test_file_is_executable(Condition *c) {
+ struct stat st;
+
+ assert(c);
+ assert(c->parameter);
+ assert(c->type == CONDITION_FILE_IS_EXECUTABLE);
+
+ return (stat(c->parameter, &st) >= 0 &&
+ S_ISREG(st.st_mode) &&
+ (st.st_mode & 0111));
+}
+
+static int condition_test_null(Condition *c) {
+ assert(c);
+ assert(c->type == CONDITION_NULL);
+
+ /* Note that during parsing we already evaluate the string and
+ * store it in c->negate */
+ return true;
+}
+
+int condition_test(Condition *c) {
+
+ static int (*const condition_tests[_CONDITION_TYPE_MAX])(Condition *c) = {
+ [CONDITION_PATH_EXISTS] = condition_test_path_exists,
+ [CONDITION_PATH_EXISTS_GLOB] = condition_test_path_exists_glob,
+ [CONDITION_PATH_IS_DIRECTORY] = condition_test_path_is_directory,
+ [CONDITION_PATH_IS_SYMBOLIC_LINK] = condition_test_path_is_symbolic_link,
+ [CONDITION_PATH_IS_MOUNT_POINT] = condition_test_path_is_mount_point,
+ [CONDITION_PATH_IS_READ_WRITE] = condition_test_path_is_read_write,
+ [CONDITION_DIRECTORY_NOT_EMPTY] = condition_test_directory_not_empty,
+ [CONDITION_FILE_NOT_EMPTY] = condition_test_file_not_empty,
+ [CONDITION_FILE_IS_EXECUTABLE] = condition_test_file_is_executable,
+ [CONDITION_KERNEL_COMMAND_LINE] = condition_test_kernel_command_line,
+ [CONDITION_VIRTUALIZATION] = condition_test_virtualization,
+ [CONDITION_SECURITY] = condition_test_security,
+ [CONDITION_CAPABILITY] = condition_test_capability,
+ [CONDITION_HOST] = condition_test_host,
+ [CONDITION_AC_POWER] = condition_test_ac_power,
+ [CONDITION_ARCHITECTURE] = condition_test_architecture,
+ [CONDITION_NEEDS_UPDATE] = condition_test_needs_update,
+ [CONDITION_FIRST_BOOT] = condition_test_first_boot,
+ [CONDITION_NULL] = condition_test_null,
+ };
+
+ int r, b;
+
+ assert(c);
+ assert(c->type >= 0);
+ assert(c->type < _CONDITION_TYPE_MAX);
+
+ r = condition_tests[c->type](c);
+ if (r < 0) {
+ c->result = CONDITION_ERROR;
+ return r;
+ }
+
+ b = (r > 0) == !c->negate;
+ c->result = b ? CONDITION_SUCCEEDED : CONDITION_FAILED;
+ return b;
+}
+
+void condition_dump(Condition *c, FILE *f, const char *prefix, const char *(*to_string)(ConditionType t)) {
+ assert(c);
+ assert(f);
+
+ if (!prefix)
+ prefix = "";
+
+ fprintf(f,
+ "%s\t%s: %s%s%s %s\n",
+ prefix,
+ to_string(c->type),
+ c->trigger ? "|" : "",
+ c->negate ? "!" : "",
+ c->parameter,
+ condition_result_to_string(c->result));
+}
+
+void condition_dump_list(Condition *first, FILE *f, const char *prefix, const char *(*to_string)(ConditionType t)) {
+ Condition *c;
+
+ LIST_FOREACH(conditions, c, first)
+ condition_dump(c, f, prefix, to_string);
+}
+
+static const char* const condition_type_table[_CONDITION_TYPE_MAX] = {
+ [CONDITION_ARCHITECTURE] = "ConditionArchitecture",
+ [CONDITION_VIRTUALIZATION] = "ConditionVirtualization",
+ [CONDITION_HOST] = "ConditionHost",
+ [CONDITION_KERNEL_COMMAND_LINE] = "ConditionKernelCommandLine",
+ [CONDITION_SECURITY] = "ConditionSecurity",
+ [CONDITION_CAPABILITY] = "ConditionCapability",
+ [CONDITION_AC_POWER] = "ConditionACPower",
+ [CONDITION_NEEDS_UPDATE] = "ConditionNeedsUpdate",
+ [CONDITION_FIRST_BOOT] = "ConditionFirstBoot",
+ [CONDITION_PATH_EXISTS] = "ConditionPathExists",
+ [CONDITION_PATH_EXISTS_GLOB] = "ConditionPathExistsGlob",
+ [CONDITION_PATH_IS_DIRECTORY] = "ConditionPathIsDirectory",
+ [CONDITION_PATH_IS_SYMBOLIC_LINK] = "ConditionPathIsSymbolicLink",
+ [CONDITION_PATH_IS_MOUNT_POINT] = "ConditionPathIsMountPoint",
+ [CONDITION_PATH_IS_READ_WRITE] = "ConditionPathIsReadWrite",
+ [CONDITION_DIRECTORY_NOT_EMPTY] = "ConditionDirectoryNotEmpty",
+ [CONDITION_FILE_NOT_EMPTY] = "ConditionFileNotEmpty",
+ [CONDITION_FILE_IS_EXECUTABLE] = "ConditionFileIsExecutable",
+ [CONDITION_NULL] = "ConditionNull"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(condition_type, ConditionType);
+
+static const char* const assert_type_table[_CONDITION_TYPE_MAX] = {
+ [CONDITION_ARCHITECTURE] = "AssertArchitecture",
+ [CONDITION_VIRTUALIZATION] = "AssertVirtualization",
+ [CONDITION_HOST] = "AssertHost",
+ [CONDITION_KERNEL_COMMAND_LINE] = "AssertKernelCommandLine",
+ [CONDITION_SECURITY] = "AssertSecurity",
+ [CONDITION_CAPABILITY] = "AssertCapability",
+ [CONDITION_AC_POWER] = "AssertACPower",
+ [CONDITION_NEEDS_UPDATE] = "AssertNeedsUpdate",
+ [CONDITION_FIRST_BOOT] = "AssertFirstBoot",
+ [CONDITION_PATH_EXISTS] = "AssertPathExists",
+ [CONDITION_PATH_EXISTS_GLOB] = "AssertPathExistsGlob",
+ [CONDITION_PATH_IS_DIRECTORY] = "AssertPathIsDirectory",
+ [CONDITION_PATH_IS_SYMBOLIC_LINK] = "AssertPathIsSymbolicLink",
+ [CONDITION_PATH_IS_MOUNT_POINT] = "AssertPathIsMountPoint",
+ [CONDITION_PATH_IS_READ_WRITE] = "AssertPathIsReadWrite",
+ [CONDITION_DIRECTORY_NOT_EMPTY] = "AssertDirectoryNotEmpty",
+ [CONDITION_FILE_NOT_EMPTY] = "AssertFileNotEmpty",
+ [CONDITION_FILE_IS_EXECUTABLE] = "AssertFileIsExecutable",
+ [CONDITION_NULL] = "AssertNull"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(assert_type, ConditionType);
+
+static const char* const condition_result_table[_CONDITION_RESULT_MAX] = {
+ [CONDITION_UNTESTED] = "untested",
+ [CONDITION_SUCCEEDED] = "succeeded",
+ [CONDITION_FAILED] = "failed",
+ [CONDITION_ERROR] = "error",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(condition_result, ConditionResult);