Systemd/src/sysctl/sysctl.c
Zbigniew Jędrzejewski-Szmek ca78ad1de9 headers: remove unneeded includes from util.h
This means we need to include many more headers in various files that simply
included util.h before, but it seems cleaner to do it this way.
2019-03-27 11:53:12 +01:00

322 lines
9.8 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
#include <errno.h>
#include <getopt.h>
#include <limits.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "conf-files.h"
#include "def.h"
#include "fd-util.h"
#include "fileio.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 bool arg_cat_config = false;
static PagerFlags arg_pager_flags = 0;
STATIC_DESTRUCTOR_REGISTER(arg_prefixes, strv_freep);
static int apply_all(OrderedHashmap *sysctl_options) {
char *property, *value;
Iterator i;
int r = 0;
ORDERED_HASHMAP_FOREACH_KEY(value, property, sysctl_options, i) {
int k;
k = sysctl_write(property, value);
if (k < 0) {
/* 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 at LOG_NOTICE level, and proceed without
* failing. (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 (IN_SET(k, -EPERM, -EACCES, -EROFS, -ENOENT))
log_notice_errno(k, "Couldn't write '%s' to '%s', ignoring: %m", value, property);
else {
log_error_errno(k, "Couldn't write '%s' to '%s': %m", value, property);
if (r == 0)
r = k;
}
}
}
return r;
}
static bool test_prefix(const char *p) {
char **i;
if (strv_isempty(arg_prefixes))
return true;
STRV_FOREACH(i, arg_prefixes) {
const char *t;
t = path_startswith(*i, "/proc/sys/");
if (!t)
t = *i;
if (path_startswith(p, t))
return true;
}
return false;
}
static int parse_file(OrderedHashmap *sysctl_options, const char *path, bool ignore_enoent) {
_cleanup_fclose_ FILE *f = NULL;
unsigned c = 0;
int r;
assert(path);
r = search_and_fopen(path, "re", NULL, (const char**) CONF_PATHS_STRV("sysctl.d"), &f);
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", path);
for (;;) {
char *p, *value, *new_value, *property, *existing;
_cleanup_free_ char *l = NULL;
void *v;
int k;
k = read_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", path);
c++;
p = strstrip(l);
if (isempty(p))
continue;
if (strchr(COMMENTS "\n", *p))
continue;
value = strchr(p, '=');
if (!value) {
log_error("Line is not an assignment at '%s:%u': %s", path, c, p);
if (r == 0)
r = -EINVAL;
continue;
}
*value = 0;
value++;
p = sysctl_normalize(strstrip(p));
value = strstrip(value);
if (!test_prefix(p))
continue;
existing = ordered_hashmap_get2(sysctl_options, p, &v);
if (existing) {
if (streq(value, existing))
continue;
log_debug("Overwriting earlier assignment of %s at '%s:%u'.", p, path, c);
free(ordered_hashmap_remove(sysctl_options, p));
free(v);
}
property = strdup(p);
if (!property)
return log_oom();
new_value = strdup(value);
if (!new_value) {
free(property);
return log_oom();
}
k = ordered_hashmap_put(sysctl_options, property, new_value);
if (k < 0) {
log_error_errno(k, "Failed to add sysctl variable %s to hashmap: %m", property);
free(property);
free(new_value);
return k;
}
}
return r;
}
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"
" --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_PREFIX,
ARG_NO_PAGER,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "cat-config", no_argument, NULL, ARG_CAT_CONFIG },
{ "prefix", required_argument, NULL, ARG_PREFIX },
{ "no-pager", no_argument, NULL, ARG_NO_PAGER },
{}
};
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_config = true;
break;
case ARG_PREFIX: {
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);
if (path_startswith(optarg, "/proc/sys"))
p = strdup(optarg);
else
p = strappend("/proc/sys/", 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 '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option");
}
if (arg_cat_config && argc > optind)
return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
"Positional arguments are not allowed with --cat-config");
return 1;
}
static int run(int argc, char *argv[]) {
_cleanup_(ordered_hashmap_free_free_freep) OrderedHashmap *sysctl_options = NULL;
int r, k;
r = parse_argv(argc, argv);
if (r <= 0)
return r;
log_setup_service();
umask(0022);
sysctl_options = ordered_hashmap_new(&path_hash_ops);
if (!sysctl_options)
return log_oom();
r = 0;
if (argc > optind) {
int i;
for (i = optind; i < argc; i++) {
k = parse_file(sysctl_options, argv[i], false);
if (k < 0 && r == 0)
r = k;
}
} else {
_cleanup_strv_free_ char **files = NULL;
char **f;
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_config) {
(void) pager_open(arg_pager_flags);
return cat_files(NULL, files, 0);
}
STRV_FOREACH(f, files) {
k = parse_file(sysctl_options, *f, true);
if (k < 0 && r == 0)
r = k;
}
}
k = apply_all(sysctl_options);
if (k < 0 && r == 0)
r = k;
return r;
}
DEFINE_MAIN_FUNCTION(run);