NetworkManager/src/initrd/nm-initrd-generator.c

/* SPDX-License-Identifier: LGPL-2.1+ */
/*
 * Copyright (C) 2018 Red Hat, Inc.
 */

#include "nm-default.h"
#include "nm-core-utils.h"
#include "nm-core-internal.h"
#include "nm-keyfile/nm-keyfile-internal.h"
#include "nm-initrd-generator.h"
#include "nm-glib-aux/nm-io-utils.h"

/*****************************************************************************/

#define _NMLOG(level, domain, ...)                                 \
    nm_log((level),                                                \
           (domain),                                               \
           NULL,                                                   \
           NULL,                                                   \
           "initrd-generator: " _NM_UTILS_MACRO_FIRST(__VA_ARGS__) \
               _NM_UTILS_MACRO_REST(__VA_ARGS__))

/*****************************************************************************/

static void
output_conn(gpointer key, gpointer value, gpointer user_data)
{
    const char *          basename        = key;
    NMConnection *        connection      = value;
    char *                connections_dir = user_data;
    nm_auto_unref_keyfile GKeyFile *file  = NULL;
    gs_free char *                  data  = NULL;
    gs_free_error GError *error           = NULL;
    gsize                 len;

    if (!nm_connection_normalize(connection, NULL, NULL, &error))
        goto err_out;

    file = nm_keyfile_write(connection, NM_KEYFILE_HANDLER_FLAGS_NONE, NULL, NULL, &error);
    if (file == NULL)
        goto err_out;

    data = g_key_file_to_data(file, &len, &error);
    if (!data)
        goto err_out;

    if (connections_dir) {
        gs_free char *filename      = NULL;
        gs_free char *full_filename = NULL;

        filename      = nm_keyfile_utils_create_filename(basename, TRUE);
        full_filename = g_build_filename(connections_dir, filename, NULL);

        if (!nm_utils_file_set_contents(full_filename, data, len, 0600, NULL, &error))
            goto err_out;
    } else
        g_print("\n*** Connection '%s' ***\n\n%s", basename, data);

    return;
err_out:
    g_print("%s\n", error->message);
}

#define DEFAULT_SYSFS_DIR       "/sys"
#define DEFAULT_INITRD_DATA_DIR NMRUNDIR "/initrd"

int
main(int argc, char *argv[])
{
    GHashTable *       connections;
    gs_free char *     connections_dir  = NULL;
    gs_free char *     initrd_dir       = NULL;
    gs_free char *     sysfs_dir        = NULL;
    gboolean           dump_to_stdout   = FALSE;
    gs_strfreev char **remaining        = NULL;
    GOptionEntry       option_entries[] = {
        {"connections-dir",
         'c',
         0,
         G_OPTION_ARG_FILENAME,
         &connections_dir,
         "Output connection directory",
         NM_KEYFILE_PATH_NAME_RUN},
        {"initrd-data-dir",
         'i',
         0,
         G_OPTION_ARG_FILENAME,
         &initrd_dir,
         "Output initrd data directory",
         DEFAULT_INITRD_DATA_DIR},
        {"sysfs-dir",
         'd',
         0,
         G_OPTION_ARG_FILENAME,
         &sysfs_dir,
         "The sysfs mount point",
         DEFAULT_SYSFS_DIR},
        {"stdout",
         's',
         0,
         G_OPTION_ARG_NONE,
         &dump_to_stdout,
         "Dump connections to standard output",
         NULL},
        {G_OPTION_REMAINING, '\0', 0, G_OPTION_ARG_STRING_ARRAY, &remaining, NULL, NULL},
        {NULL}};
    nm_auto_free_option_context GOptionContext *option_context = NULL;
    gs_free_error GError *error                                = NULL;
    gs_free char *        hostname                             = NULL;
    int                   errsv;

    option_context = g_option_context_new(
        "-- [ip=...] [rd.route=...] [bridge=...] [bond=...] [team=...] [vlan=...] "
        "[bootdev=...] [nameserver=...] [rd.peerdns=...] [rd.bootif=...] [BOOTIF=...] "
        "[rd.znet=...] ... ");

    g_option_context_set_summary(option_context, "Generate early NetworkManager configuration.");
    g_option_context_set_description(
        option_context,
        "This tool scans the command line for options relevant to network\n"
        "configuration and creates configuration files for an early instance\n"
        "of NetworkManager run from the initial ramdisk during early boot.");
    g_option_context_add_main_entries(option_context, option_entries, GETTEXT_PACKAGE);

    if (!g_option_context_parse(option_context, &argc, &argv, &error)) {
        _LOGW(LOGD_CORE, "%s", error->message);
        return 1;
    }

    if (!remaining) {
        /* No arguments, no networking. Don't bother. */
        return 0;
    }

    if (!connections_dir)
        connections_dir = g_strdup(NM_KEYFILE_PATH_NAME_RUN);
    if (!sysfs_dir)
        sysfs_dir = g_strdup(DEFAULT_SYSFS_DIR);
    if (!initrd_dir)
        initrd_dir = g_strdup(DEFAULT_INITRD_DATA_DIR);
    if (dump_to_stdout)
        nm_clear_g_free(&connections_dir);

    if (connections_dir && g_mkdir_with_parents(connections_dir, 0755) != 0) {
        errsv = errno;
        _LOGW(LOGD_CORE, "%s: %s", connections_dir, nm_strerror_native(errsv));
        return 1;
    }

    connections = nmi_cmdline_reader_parse(sysfs_dir, (const char *const *) remaining, &hostname);

    g_hash_table_foreach(connections, output_conn, connections_dir);
    g_hash_table_destroy(connections);

    if (dump_to_stdout) {
        if (hostname)
            g_print("\n*** Hostname '%s' ***\n", hostname);
    } else {
        if (g_mkdir_with_parents(initrd_dir, 0755) != 0) {
            errsv = errno;
            _LOGW(LOGD_CORE, "%s: %s", initrd_dir, nm_strerror_native(errsv));
            return 1;
        }

        if (hostname) {
            gs_free char *hostname_file = NULL;
            gs_free char *data          = NULL;

            hostname_file = g_strdup_printf("%s/hostname", initrd_dir);
            data          = g_strdup_printf("%s\n", hostname);

            if (!g_file_set_contents(hostname_file, data, strlen(data), &error)) {
                _LOGW(LOGD_CORE, "%s: %s", hostname_file, error->message);
                return 1;
            }
        }
    }

    return 0;
}