Adding upstream version 255.4.upstream/255.4

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

2 files changed, 499 insertions, 0 deletions

diff --git a/src/sysctl/meson.build b/src/sysctl/meson.build
new file mode 100644
index 0000000..1fb85c2
--- /dev/null
+++ b/src/sysctl/meson.build
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+executables += [
+        libexec_template + {
+                'name' : 'systemd-sysctl',
+                'public' : true,
+                'sources' : files('sysctl.c'),
+        },
+]
diff --git a/src/sysctl/sysctl.c b/src/sysctl/sysctl.c
new file mode 100644
index 0000000..aac965f
--- /dev/null
+++ b/src/sysctl/sysctl.c
@@ -0,0 +1,490 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <getopt.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "build.h"
+#include "conf-files.h"
+#include "constants.h"
+#include "creds-util.h"
+#include "errno-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "glob-util.h"
+#include "hashmap.h"
+#include "log.h"
+#include "main-func.h"
+#include "pager.h"
+#include "path-util.h"
+#include "pretty-print.h"
+#include "string-util.h"
+#include "strv.h"
+#include "sysctl-util.h"
+
+static char **arg_prefixes = NULL;
+static CatFlags arg_cat_flags = CAT_CONFIG_OFF;
+static bool arg_strict = false;
+static PagerFlags arg_pager_flags = 0;
+
+STATIC_DESTRUCTOR_REGISTER(arg_prefixes, strv_freep);
+
+typedef struct Option {
+        char *key;
+        char *value;
+        bool ignore_failure;
+} Option;
+
+static Option *option_free(Option *o) {
+        if (!o)
+                return NULL;
+
+        free(o->key);
+        free(o->value);
+
+        return mfree(o);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Option*, option_free);
+DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(option_hash_ops, char, string_hash_func, string_compare_func, Option, option_free);
+
+static bool test_prefix(const char *p) {
+        if (strv_isempty(arg_prefixes))
+                return true;
+
+        return path_startswith_strv(p, arg_prefixes);
+}
+
+static Option *option_new(
+                const char *key,
+                const char *value,
+                bool ignore_failure) {
+
+        _cleanup_(option_freep) Option *o = NULL;
+
+        assert(key);
+
+        o = new(Option, 1);
+        if (!o)
+                return NULL;
+
+        *o = (Option) {
+                .key = strdup(key),
+                .value = value ? strdup(value) : NULL,
+                .ignore_failure = ignore_failure,
+        };
+
+        if (!o->key)
+                return NULL;
+        if (value && !o->value)
+                return NULL;
+
+        return TAKE_PTR(o);
+}
+
+static int sysctl_write_or_warn(const char *key, const char *value, bool ignore_failure, bool ignore_enoent) {
+        int r;
+
+        r = sysctl_write(key, value);
+        if (r < 0) {
+                /* Proceed without failing if ignore_failure is true.
+                 * If the sysctl is not available in the kernel or we are running with reduced privileges and
+                 * cannot write it, then log about the issue, and proceed without failing. Unless strict mode
+                 * (arg_strict = true) is enabled, in which case we should fail. (EROFS is treated as a
+                 * permission problem here, since that's how container managers usually protected their
+                 * sysctls.)
+                 * In all other cases log an error and make the tool fail. */
+                if (ignore_failure || (!arg_strict && (r == -EROFS || ERRNO_IS_PRIVILEGE(r))))
+                        log_debug_errno(r, "Couldn't write '%s' to '%s', ignoring: %m", value, key);
+                else if (ignore_enoent && r == -ENOENT)
+                        log_warning_errno(r, "Couldn't write '%s' to '%s', ignoring: %m", value, key);
+                else
+                        return log_error_errno(r, "Couldn't write '%s' to '%s': %m", value, key);
+        }
+
+        return 0;
+}
+
+static int apply_glob_option_with_prefix(OrderedHashmap *sysctl_options, Option *option, const char *prefix) {
+        _cleanup_strv_free_ char **paths = NULL;
+        _cleanup_free_ char *pattern = NULL;
+        int r;
+
+        assert(sysctl_options);
+        assert(option);
+
+        if (prefix) {
+                _cleanup_free_ char *key = NULL;
+
+                r = path_glob_can_match(option->key, prefix, &key);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to check if the glob '%s' matches prefix '%s': %m",
+                                               option->key, prefix);
+                if (r == 0) {
+                        log_debug("The glob '%s' does not match prefix '%s'.", option->key, prefix);
+                        return 0;
+                }
+
+                log_debug("The glob '%s' is prefixed with '%s': '%s'", option->key, prefix, key);
+
+                if (!string_is_glob(key)) {
+                        /* The prefixed pattern is not glob anymore. Let's skip to call glob(). */
+                        if (ordered_hashmap_contains(sysctl_options, key)) {
+                                log_debug("Not setting %s (explicit setting exists).", key);
+                                return 0;
+                        }
+
+                        return sysctl_write_or_warn(key, option->value,
+                                                    /* ignore_failure = */ option->ignore_failure,
+                                                    /* ignore_enoent = */ true);
+                }
+
+                pattern = path_join("/proc/sys", key);
+        } else
+                pattern = path_join("/proc/sys", option->key);
+        if (!pattern)
+                return log_oom();
+
+        r = glob_extend(&paths, pattern, GLOB_NOCHECK);
+        if (r < 0) {
+                if (r == -ENOENT) {
+                        log_debug("No match for glob: %s", option->key);
+                        return 0;
+                }
+                if (option->ignore_failure || ERRNO_IS_PRIVILEGE(r)) {
+                        log_debug_errno(r, "Failed to resolve glob '%s', ignoring: %m", option->key);
+                        return 0;
+                } else
+                        return log_error_errno(r, "Couldn't resolve glob '%s': %m", option->key);
+        }
+
+        STRV_FOREACH(s, paths) {
+                const char *key;
+
+                assert_se(key = path_startswith(*s, "/proc/sys"));
+
+                if (ordered_hashmap_contains(sysctl_options, key)) {
+                        log_debug("Not setting %s (explicit setting exists).", key);
+                        continue;
+                }
+
+                RET_GATHER(r,
+                           sysctl_write_or_warn(key, option->value,
+                                                /* ignore_failure = */ option->ignore_failure,
+                                                /* ignore_enoent = */ !arg_strict));
+        }
+
+        return r;
+}
+
+static int apply_glob_option(OrderedHashmap *sysctl_options, Option *option) {
+        int r = 0;
+
+        if (strv_isempty(arg_prefixes))
+                return apply_glob_option_with_prefix(sysctl_options, option, NULL);
+
+        STRV_FOREACH(i, arg_prefixes)
+                RET_GATHER(r, apply_glob_option_with_prefix(sysctl_options, option, *i));
+        return r;
+}
+
+static int apply_all(OrderedHashmap *sysctl_options) {
+        Option *option;
+        int r = 0;
+
+        ORDERED_HASHMAP_FOREACH(option, sysctl_options) {
+                int k;
+
+                /* Ignore "negative match" options, they are there only to exclude stuff from globs. */
+                if (!option->value)
+                        continue;
+
+                if (string_is_glob(option->key))
+                        k = apply_glob_option(sysctl_options, option);
+                else
+                        k = sysctl_write_or_warn(option->key, option->value,
+                                                 /* ignore_failure = */ option->ignore_failure,
+                                                 /* ignore_enoent = */ !arg_strict);
+                RET_GATHER(r, k);
+        }
+
+        return r;
+}
+
+static int parse_file(OrderedHashmap **sysctl_options, const char *path, bool ignore_enoent) {
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_free_ char *pp = NULL;
+        unsigned c = 0;
+        int r;
+
+        assert(path);
+
+        r = search_and_fopen(path, "re", NULL, (const char**) CONF_PATHS_STRV("sysctl.d"), &f, &pp);
+        if (r < 0) {
+                if (ignore_enoent && r == -ENOENT)
+                        return 0;
+
+                return log_error_errno(r, "Failed to open file '%s', ignoring: %m", path);
+        }
+
+        log_debug("Parsing %s", pp);
+        for (;;) {
+                _cleanup_(option_freep) Option *new_option = NULL;
+                _cleanup_free_ char *l = NULL;
+                bool ignore_failure = false;
+                Option *existing;
+                char *value;
+                int k;
+
+                k = read_stripped_line(f, LONG_LINE_MAX, &l);
+                if (k == 0)
+                        break;
+                if (k < 0)
+                        return log_error_errno(k, "Failed to read file '%s', ignoring: %m", pp);
+
+                c++;
+
+                if (isempty(l))
+                        continue;
+                if (strchr(COMMENTS, l[0]))
+                        continue;
+
+                char *p = l;
+                value = strchr(p, '=');
+                if (value) {
+                        if (p[0] == '-') {
+                                ignore_failure = true;
+                                p++;
+                        }
+
+                        *value = 0;
+                        value++;
+                        value = strstrip(value);
+
+                } else {
+                        if (p[0] == '-')
+                                /* We have a "negative match" option. Let's continue with value==NULL. */
+                                p++;
+                        else {
+                                log_syntax(NULL, LOG_WARNING, pp, c, 0,
+                                           "Line is not an assignment, ignoring: %s", p);
+                                if (r == 0)
+                                        r = -EINVAL;
+                                continue;
+                        }
+                }
+
+                p = strstrip(p);
+                p = sysctl_normalize(p);
+
+                /* We can't filter out globs at this point, we'll need to do that later. */
+                if (!string_is_glob(p) &&
+                    !test_prefix(p))
+                        continue;
+
+                existing = ordered_hashmap_get(*sysctl_options, p);
+                if (existing) {
+                        if (streq_ptr(value, existing->value)) {
+                                existing->ignore_failure = existing->ignore_failure || ignore_failure;
+                                continue;
+                        }
+
+                        log_debug("Overwriting earlier assignment of %s at '%s:%u'.", p, pp, c);
+                        option_free(ordered_hashmap_remove(*sysctl_options, p));
+                }
+
+                new_option = option_new(p, value, ignore_failure);
+                if (!new_option)
+                        return log_oom();
+
+                k = ordered_hashmap_ensure_put(sysctl_options, &option_hash_ops, new_option->key, new_option);
+                if (k < 0)
+                        return log_error_errno(k, "Failed to add sysctl variable %s to hashmap: %m", p);
+
+                TAKE_PTR(new_option);
+        }
+
+        return r;
+}
+
+static int read_credential_lines(OrderedHashmap **sysctl_options) {
+        _cleanup_free_ char *j = NULL;
+        const char *d;
+        int r;
+
+        r = get_credentials_dir(&d);
+        if (r == -ENXIO)
+                return 0;
+        if (r < 0)
+                return log_error_errno(r, "Failed to get credentials directory: %m");
+
+        j = path_join(d, "sysctl.extra");
+        if (!j)
+                return log_oom();
+
+        (void) parse_file(sysctl_options, j, /* ignore_enoent= */ true);
+        return 0;
+}
+
+static int cat_config(char **files) {
+        pager_open(arg_pager_flags);
+
+        return cat_files(NULL, files, arg_cat_flags);
+}
+
+static int help(void) {
+        _cleanup_free_ char *link = NULL;
+        int r;
+
+        r = terminal_urlify_man("systemd-sysctl.service", "8", &link);
+        if (r < 0)
+                return log_oom();
+
+        printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
+               "Applies kernel sysctl settings.\n\n"
+               "  -h --help             Show this help\n"
+               "     --version          Show package version\n"
+               "     --cat-config       Show configuration files\n"
+               "     --tldr             Show non-comment parts of configuration\n"
+               "     --prefix=PATH      Only apply rules with the specified prefix\n"
+               "     --no-pager         Do not pipe output into a pager\n"
+               "\nSee the %s for details.\n",
+               program_invocation_short_name,
+               link);
+
+        return 0;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+        enum {
+                ARG_VERSION = 0x100,
+                ARG_CAT_CONFIG,
+                ARG_TLDR,
+                ARG_PREFIX,
+                ARG_NO_PAGER,
+                ARG_STRICT,
+        };
+
+        static const struct option options[] = {
+                { "help",       no_argument,       NULL, 'h'            },
+                { "version",    no_argument,       NULL, ARG_VERSION    },
+                { "cat-config", no_argument,       NULL, ARG_CAT_CONFIG },
+                { "tldr",       no_argument,       NULL, ARG_TLDR       },
+                { "prefix",     required_argument, NULL, ARG_PREFIX     },
+                { "no-pager",   no_argument,       NULL, ARG_NO_PAGER   },
+                { "strict",     no_argument,       NULL, ARG_STRICT     },
+                {}
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
+
+                switch (c) {
+
+                case 'h':
+                        return help();
+
+                case ARG_VERSION:
+                        return version();
+
+                case ARG_CAT_CONFIG:
+                        arg_cat_flags = CAT_CONFIG_ON;
+                        break;
+
+                case ARG_TLDR:
+                        arg_cat_flags = CAT_TLDR;
+                        break;
+
+                case ARG_PREFIX: {
+                        const char *s;
+                        char *p;
+
+                        /* We used to require people to specify absolute paths
+                         * in /proc/sys in the past. This is kinda useless, but
+                         * we need to keep compatibility. We now support any
+                         * sysctl name available. */
+                        sysctl_normalize(optarg);
+
+                        s = path_startswith(optarg, "/proc/sys");
+                        p = strdup(s ?: optarg);
+                        if (!p)
+                                return log_oom();
+
+                        if (strv_consume(&arg_prefixes, p) < 0)
+                                return log_oom();
+
+                        break;
+                }
+
+                case ARG_NO_PAGER:
+                        arg_pager_flags |= PAGER_DISABLE;
+                        break;
+
+                case ARG_STRICT:
+                        arg_strict = true;
+                        break;
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        assert_not_reached();
+                }
+
+        if (arg_cat_flags != CAT_CONFIG_OFF && argc > optind)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "Positional arguments are not allowed with --cat-config/--tldr.");
+
+        return 1;
+}
+
+static int run(int argc, char *argv[]) {
+        _cleanup_ordered_hashmap_free_ OrderedHashmap *sysctl_options = NULL;
+        int r;
+
+        r = parse_argv(argc, argv);
+        if (r <= 0)
+                return r;
+
+        log_setup();
+
+        umask(0022);
+
+        if (argc > optind) {
+                r = 0;
+
+                for (int i = optind; i < argc; i++)
+                        RET_GATHER(r, parse_file(&sysctl_options, argv[i], false));
+
+        } else {
+                _cleanup_strv_free_ char **files = NULL;
+
+                r = conf_files_list_strv(&files, ".conf", NULL, 0, (const char**) CONF_PATHS_STRV("sysctl.d"));
+                if (r < 0)
+                        return log_error_errno(r, "Failed to enumerate sysctl.d files: %m");
+
+                if (arg_cat_flags != CAT_CONFIG_OFF)
+                        return cat_config(files);
+
+                STRV_FOREACH(f, files)
+                        RET_GATHER(r, parse_file(&sysctl_options, *f, true));
+
+                RET_GATHER(r, read_credential_lines(&sysctl_options));
+        }
+
+        RET_GATHER(r, apply_all(sysctl_options));
+
+        return r;
+}
+
+DEFINE_MAIN_FUNCTION(run);