source: ogServer-Git/src/wol.c @ d89d6c6

/*
 * Copyright (C) 2020 Soleta Networks <info@soleta.eu>
 *
 * This program is free software: you can redistribute it and/or modify it under
 * the terms of the GNU Affero General Public License as published by the
 * Free Software Foundation, version 3.
 */
#include <sys/types.h>
#include <ifaddrs.h>
#include <string.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <syslog.h>
#include <stddef.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <fcntl.h>
#include "wol.h"
#include "ogAdmServer.h"

int wol_socket_open(void)
{
        unsigned int on = 1;
        int ret, s;

        s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
        if (s < 0) {
                syslog(LOG_ERR, "cannot create socket for magic packet\n");
                return -1;
        }
        ret = setsockopt(s, SOL_SOCKET, SO_BROADCAST, (unsigned int *) &on,
                         sizeof(on));
        if (ret < 0) {
                syslog(LOG_ERR, "cannot set broadcast socket\n");
                return -1;
        }

        return s;
}

bool wake_up_send(int sd, struct sockaddr_in *client,
                  const struct wol_msg *msg, const struct in_addr *addr)
{
        int ret;

        client->sin_addr.s_addr = addr->s_addr;

        ret = sendto(sd, msg, sizeof(*msg), 0,
                     (struct sockaddr *)client, sizeof(*client));
        if (ret < 0) {
                syslog(LOG_ERR, "failed to send wol\n");
                return false;
        }

        return true;
}

bool wake_up_broadcast(int sd, struct sockaddr_in *client,
                       const struct wol_msg *msg)
{
        struct sockaddr_in *broadcast_addr, addr = {};
        struct ifaddrs *ifaddr, *ifa;

        if (getifaddrs(&ifaddr) < 0) {
                syslog(LOG_ERR, "cannot get list of addresses\n");
                return false;
        }

        addr.sin_addr.s_addr = htonl(INADDR_BROADCAST);

        for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
                if (ifa->ifa_addr == NULL ||
                    ifa->ifa_addr->sa_family != AF_INET ||
                    strcmp(ifa->ifa_name, interface) != 0)
                        continue;

                broadcast_addr =
                        (struct sockaddr_in *)ifa->ifa_ifu.ifu_broadaddr;
                addr.sin_addr.s_addr = broadcast_addr->sin_addr.s_addr;
                break;
        }
        freeifaddrs(ifaddr);

        return wake_up_send(sd, client, msg, &addr.sin_addr);
}