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-rw-r--r--src/sysctl/sysctl.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/src/sysctl/sysctl.c b/src/sysctl/sysctl.c
new file mode 100644
index 0000000000..035e0ec321
--- /dev/null
+++ b/src/sysctl/sysctl.c
@@ -0,0 +1,336 @@
+/*-*- 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 <stdbool.h>
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <limits.h>
+#include <getopt.h>
+
+#include "log.h"
+#include "strv.h"
+#include "util.h"
+#include "strv.h"
+#include "hashmap.h"
+#include "path-util.h"
+#include "conf-files.h"
+
+#define PROC_SYS_PREFIX "/proc/sys/"
+
+static char **arg_prefixes;
+static Hashmap *sysctl_options;
+
+static int apply_sysctl(const char *property, const char *value) {
+ char *p, *n;
+ int r = 0, k;
+
+ log_debug("Setting '%s' to '%s'", property, value);
+
+ p = new(char, sizeof(PROC_SYS_PREFIX) + strlen(property));
+ if (!p)
+ return log_oom();
+
+ n = stpcpy(p, PROC_SYS_PREFIX);
+ strcpy(n, property);
+
+ for (; *n; n++)
+ if (*n == '.')
+ *n = '/';
+
+ if (!strv_isempty(arg_prefixes)) {
+ char **i;
+ bool good = false;
+
+ STRV_FOREACH(i, arg_prefixes)
+ if (path_startswith(p, *i)) {
+ good = true;
+ break;
+ }
+
+ if (!good) {
+ log_debug("Skipping %s", p);
+ free(p);
+ return 0;
+ }
+ }
+
+ k = write_one_line_file(p, value);
+ if (k < 0) {
+
+ log_full(k == -ENOENT ? LOG_DEBUG : LOG_WARNING,
+ "Failed to write '%s' to '%s': %s", value, p, strerror(-k));
+
+ if (k != -ENOENT && r == 0)
+ r = k;
+ }
+
+ free(p);
+
+ return r;
+}
+
+static int apply_all(void) {
+ int r = 0;
+ char *property, *value;
+ Iterator i;
+
+ HASHMAP_FOREACH_KEY(value, property, sysctl_options, i) {
+ int k;
+
+ k = apply_sysctl(property, value);
+ if (k < 0 && r == 0)
+ r = k;
+ }
+ return r;
+}
+
+static int parse_file(const char *path, bool ignore_enoent) {
+ FILE *f;
+ int r = 0;
+
+ assert(path);
+
+ f = fopen(path, "re");
+ if (!f) {
+ if (ignore_enoent && errno == ENOENT)
+ return 0;
+
+ log_error("Failed to open file '%s', ignoring: %m", path);
+ return -errno;
+ }
+
+ log_debug("parse: %s\n", path);
+ while (!feof(f)) {
+ char l[LINE_MAX], *p, *value, *new_value, *property;
+
+ if (!fgets(l, sizeof(l), f)) {
+ if (feof(f))
+ break;
+
+ log_error("Failed to read file '%s', ignoring: %m", path);
+ r = -errno;
+ goto finish;
+ }
+
+ p = strstrip(l);
+
+ if (!*p)
+ continue;
+
+ if (strchr(COMMENTS, *p))
+ continue;
+
+ value = strchr(p, '=');
+ if (!value) {
+ log_error("Line is not an assignment in file '%s': %s", path, value);
+
+ if (r == 0)
+ r = -EINVAL;
+ continue;
+ }
+
+ *value = 0;
+ value++;
+
+ property = strdup(strstrip(p));
+ if (!property) {
+ r = log_oom();
+ goto finish;
+ }
+
+ new_value = strdup(strstrip(value));
+ if (!new_value) {
+ free(property);
+ r = log_oom();
+ goto finish;
+ }
+
+ r = hashmap_put(sysctl_options, property, new_value);
+ if (r < 0) {
+ if (r == -EEXIST) {
+ /* ignore this "error" to avoid returning it
+ * for the function when this is the last key
+ * in the file being parsed. */
+ r = 0;
+ log_debug("Skipping previously assigned sysctl variable %s", property);
+ } else
+ log_error("Failed to add sysctl variable %s to hashmap: %s", property, strerror(-r));
+
+ free(property);
+ free(new_value);
+ if (r != 0)
+ goto finish;
+ }
+ }
+
+finish:
+ fclose(f);
+
+ return r;
+}
+
+static int help(void) {
+
+ printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
+ "Applies kernel sysctl settings.\n\n"
+ " -h --help Show this help\n"
+ " --prefix=PATH Only apply rules that apply to paths with the specified prefix\n",
+ program_invocation_short_name);
+
+ return 0;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+ enum {
+ ARG_PREFIX
+ };
+
+ static const struct option options[] = {
+ { "help", no_argument, NULL, 'h' },
+ { "prefix", required_argument, NULL, ARG_PREFIX },
+ { NULL, 0, NULL, 0 }
+ };
+
+ int c;
+
+ assert(argc >= 0);
+ assert(argv);
+
+ while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
+
+ switch (c) {
+
+ case 'h':
+ help();
+ return 0;
+
+ case ARG_PREFIX: {
+ char *p;
+ char **l;
+
+ for (p = optarg; *p; p++)
+ if (*p == '.')
+ *p = '/';
+
+ l = strv_append(arg_prefixes, optarg);
+ if (!l)
+ return log_oom();
+
+ strv_free(arg_prefixes);
+ arg_prefixes = l;
+
+ break;
+ }
+
+ case '?':
+ return -EINVAL;
+
+ default:
+ log_error("Unknown option code %c", c);
+ return -EINVAL;
+ }
+ }
+
+ return 1;
+}
+
+int main(int argc, char *argv[]) {
+ int r = 0, k;
+ char *property, *value;
+ Iterator it;
+
+ r = parse_argv(argc, argv);
+ if (r <= 0)
+ return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ sysctl_options = hashmap_new(string_hash_func, string_compare_func);
+ if (!sysctl_options) {
+ r = log_oom();
+ goto finish;
+ }
+
+ r = 0;
+
+ if (argc > optind) {
+ int i;
+
+ for (i = optind; i < argc; i++) {
+ k = parse_file(argv[i], false);
+ if (k < 0)
+ r = k;
+ }
+ } else {
+ char **files, **f;
+
+ r = conf_files_list(&files, ".conf",
+ "/etc/sysctl.d",
+ "/run/sysctl.d",
+ "/usr/local/lib/sysctl.d",
+ "/usr/lib/sysctl.d",
+#ifdef HAVE_SPLIT_USR
+ "/lib/sysctl.d",
+#endif
+ NULL);
+ if (r < 0) {
+ log_error("Failed to enumerate sysctl.d files: %s", strerror(-r));
+ goto finish;
+ }
+
+ /* We parse the files in decreasing order of precedence.
+ * parse_file() will skip keys that were already assigned. */
+
+ r = parse_file("/etc/sysctl.conf", true);
+
+ f = files + strv_length(files) - 1;
+ STRV_FOREACH_BACKWARDS(f, files) {
+ k = parse_file(*f, true);
+ if (k < 0)
+ r = k;
+ }
+
+ strv_free(files);
+ }
+
+ k = apply_all();
+ if (k < 0)
+ r = k;
+
+finish:
+ HASHMAP_FOREACH_KEY(value, property, sysctl_options, it) {
+ hashmap_remove(sysctl_options, property);
+ free(property);
+ free(value);
+ }
+ hashmap_free(sysctl_options);
+
+ strv_free(arg_prefixes);
+
+ return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-12-20 22:13:20 +0000