Files
systemd/src/debug-generator/debug-generator.c

264 lines
8.8 KiB
C

/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <unistd.h>
#include "alloc-util.h"
#include "creds-util.h"
#include "dropin.h"
#include "errno-util.h"
#include "fd-util.h"
#include "fileio-label.h"
#include "generator.h"
#include "initrd-util.h"
#include "parse-util.h"
#include "path-util.h"
#include "proc-cmdline.h"
#include "recurse-dir.h"
#include "special.h"
#include "string-util.h"
#include "strv.h"
#include "unit-file.h"
#include "unit-name.h"
static const char *arg_dest = NULL;
static char *arg_default_unit = NULL;
static char **arg_mask = NULL;
static char **arg_wants = NULL;
static bool arg_debug_shell = false;
static char *arg_debug_tty = NULL;
static char *arg_default_debug_tty = NULL;
STATIC_DESTRUCTOR_REGISTER(arg_default_unit, freep);
STATIC_DESTRUCTOR_REGISTER(arg_mask, strv_freep);
STATIC_DESTRUCTOR_REGISTER(arg_wants, strv_freep);
STATIC_DESTRUCTOR_REGISTER(arg_debug_tty, freep);
STATIC_DESTRUCTOR_REGISTER(arg_default_debug_tty, freep);
static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
int r;
assert(key);
if (streq(key, "systemd.mask")) {
char *n;
if (proc_cmdline_value_missing(key, value))
return 0;
r = unit_name_mangle(value, UNIT_NAME_MANGLE_WARN, &n);
if (r < 0)
return log_error_errno(r, "Failed to glob unit name: %m");
if (strv_consume(&arg_mask, n) < 0)
return log_oom();
} else if (streq(key, "systemd.wants")) {
char *n;
if (proc_cmdline_value_missing(key, value))
return 0;
r = unit_name_mangle(value, UNIT_NAME_MANGLE_WARN, &n);
if (r < 0)
return log_error_errno(r, "Failed to glob unit name: %m");
if (strv_consume(&arg_wants, n) < 0)
return log_oom();
} else if (proc_cmdline_key_streq(key, "systemd.debug_shell")) {
r = value ? parse_boolean(value) : 1;
arg_debug_shell = r != 0;
if (r >= 0)
return 0;
return free_and_strdup_warn(&arg_debug_tty, skip_dev_prefix(value));
} else if (proc_cmdline_key_streq(key, "systemd.default_debug_tty")) {
if (proc_cmdline_value_missing(key, value))
return 0;
return free_and_strdup_warn(&arg_default_debug_tty, skip_dev_prefix(value));
} else if (streq(key, "systemd.unit")) {
if (proc_cmdline_value_missing(key, value))
return 0;
return free_and_strdup_warn(&arg_default_unit, value);
} else if (!value) {
const char *target;
target = runlevel_to_target(key);
if (target)
return free_and_strdup_warn(&arg_default_unit, target);
}
return 0;
}
static int generate_mask_symlinks(void) {
int r = 0;
STRV_FOREACH(u, arg_mask) {
_cleanup_free_ char *p = NULL;
p = path_join(arg_dest, *u);
if (!p)
return log_oom();
if (symlink("/dev/null", p) < 0)
RET_GATHER(r, log_error_errno(errno, "Failed to create mask symlink '%s': %m", p));
}
return r;
}
static int generate_wants_symlinks(void) {
int r = 0;
STRV_FOREACH(u, arg_wants) {
_cleanup_free_ char *f = NULL;
const char *target;
/* This should match what do_queue_default_job() in core/main.c does. */
if (arg_default_unit)
target = arg_default_unit;
else if (in_initrd())
target = SPECIAL_INITRD_TARGET;
else
target = SPECIAL_DEFAULT_TARGET;
f = path_join(SYSTEM_DATA_UNIT_DIR, *u);
if (!f)
return log_oom();
RET_GATHER(r, generator_add_symlink(arg_dest, target, "wants", f));
}
return r;
}
static int install_debug_shell_dropin(void) {
const char *tty = arg_debug_tty ?: arg_default_debug_tty;
int r;
if (!tty || path_equal(tty, skip_dev_prefix(DEBUGTTY)))
return 0;
r = write_drop_in_format(arg_dest, "debug-shell.service", 50, "tty",
"# Automatically generated by systemd-debug-generator\n\n"
"[Unit]\n"
"Description=Early root shell on /dev/%s FOR DEBUGGING ONLY\n"
"ConditionPathExists=\n"
"\n[Service]\n"
"TTYPath=/dev/%s\n",
tty, tty);
if (r < 0)
return log_warning_errno(r, "Failed to write drop-in for debug-shell.service: %m");
return 1;
}
static int process_unit_credentials(const char *credentials_dir) {
_cleanup_free_ DirectoryEntries *des = NULL;
int r;
assert(credentials_dir);
r = readdir_all_at(AT_FDCWD, credentials_dir, RECURSE_DIR_SORT|RECURSE_DIR_IGNORE_DOT|RECURSE_DIR_ENSURE_TYPE, &des);
if (r < 0)
return log_error_errno(r, "Failed to enumerate credentials from credentials directory '%s': %m", credentials_dir);
FOREACH_ARRAY(i, des->entries, des->n_entries) {
struct dirent *de = *i;
const char *unit, *dropin;
if (de->d_type != DT_REG)
continue;
unit = startswith(de->d_name, "systemd.extra-unit.");
dropin = startswith(de->d_name, "systemd.unit-dropin.");
if (!unit && !dropin)
continue;
if (!unit_name_is_valid(unit ?: dropin, UNIT_NAME_ANY)) {
log_warning("Invalid unit name '%s' in credential '%s', ignoring.",
unit ?: dropin, de->d_name);
continue;
}
_cleanup_free_ char *d = NULL;
r = read_credential_with_decryption(de->d_name, (void**) &d, NULL);
if (r < 0) {
log_warning_errno(r, "Failed to read credential '%s', ignoring: %m", de->d_name);
continue;
}
if (unit) {
_cleanup_free_ char *p = NULL;
p = path_join(arg_dest, unit);
if (!p)
return log_oom();
r = write_string_file_atomic_label(p, d);
if (r < 0) {
log_warning_errno(r, "Failed to write unit file '%s' from credential '%s', ignoring: %m",
unit, de->d_name);
continue;
}
log_debug("Wrote unit file '%s' from credential '%s'", unit, de->d_name);
} else if (dropin) {
r = write_drop_in(arg_dest, dropin, 50, "credential", d);
if (r < 0) {
log_warning_errno(r, "Failed to write drop-in for unit '%s' from credential '%s', ignoring: %m",
dropin, de->d_name);
continue;
}
log_debug("Wrote drop-in for unit '%s' from credential '%s'", dropin, de->d_name);
} else
assert_not_reached();
}
return 0;
}
static int run(const char *dest, const char *dest_early, const char *dest_late) {
const char *credentials_dir;
int r;
assert_se(arg_dest = dest_early);
r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_RD_STRICT | PROC_CMDLINE_STRIP_RD_PREFIX);
if (r < 0)
log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
if (arg_debug_shell) {
if (strv_extend(&arg_wants, "debug-shell.service") < 0)
return log_oom();
RET_GATHER(r, install_debug_shell_dropin());
}
if (get_credentials_dir(&credentials_dir) >= 0)
RET_GATHER(r, process_unit_credentials(credentials_dir));
if (get_encrypted_credentials_dir(&credentials_dir) >= 0)
RET_GATHER(r, process_unit_credentials(credentials_dir));
RET_GATHER(r, generate_mask_symlinks());
RET_GATHER(r, generate_wants_symlinks());
return r;
}
DEFINE_MAIN_GENERATOR_FUNCTION(run);