/*
 * android.c - Setup IPC for shadowsocks-android
 *
 * Copyright (C) 2013 - 2016, Max Lv <max.c.lv@gmail.com>
 *
 * This file is part of the shadowsocks-libev.
 *
 * shadowsocks-libev is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * shadowsocks-libev is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with shadowsocks-libev; see the file COPYING. If not, see
 * <http://www.gnu.org/licenses/>.
 */

#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <locale.h>
#include <signal.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>

#include <errno.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/tcp.h>

#include <sys/un.h>
#include <ancillary.h>

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "netutils.h"
#include "utils.h"

extern char *prefix;

int protect_socket(int fd)
{
    int sock;
    struct sockaddr_un addr;

    if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
        LOGE("[android] socket() failed: %s (socket fd = %d)\n", strerror(errno), sock);
        return -1;
    }

    // Set timeout to 1s
    struct timeval tv;
    tv.tv_sec  = 1;
    tv.tv_usec = 0;
    setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv, sizeof(struct timeval));
    setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (char *)&tv, sizeof(struct timeval));

    char path[257];
    sprintf(path, "%s/protect_path", prefix);

    memset(&addr, 0, sizeof(addr));
    addr.sun_family = AF_UNIX;
    strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);

    if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        LOGE("[android] connect() failed: %s (socket fd = %d), path: %s\n",
             strerror(errno), sock, path);
        close(sock);
        return -1;
    }

    if (ancil_send_fd(sock, fd)) {
        ERROR("[android] ancil_send_fd");
        close(sock);
        return -1;
    }

    char ret = 0;

    if (recv(sock, &ret, 1, 0) == -1) {
        ERROR("[android] recv");
        close(sock);
        return -1;
    }

    close(sock);
    return ret;
}

int send_traffic_stat(uint64_t tx, uint64_t rx)
{
    int sock;
    struct sockaddr_un addr;

    if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) {
        LOGE("[android] socket() failed: %s (socket fd = %d)\n", strerror(errno), sock);
        return -1;
    }

    // Set timeout to 1s
    struct timeval tv;
    tv.tv_sec  = 1;
    tv.tv_usec = 0;
    setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv, sizeof(struct timeval));
    setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, (char *)&tv, sizeof(struct timeval));

    char path[257];
    sprintf(path, "%s/stat_path", prefix);

    memset(&addr, 0, sizeof(addr));
    addr.sun_family = AF_UNIX;
    strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);

    if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
        LOGE("[android] connect() failed: %s (socket fd = %d), path: %s\n",
             strerror(errno), sock, path);
        close(sock);
        return -1;
    }

    uint64_t stat[2] = { tx, rx };

    if (send(sock, stat, sizeof(stat), 0) == -1) {
        ERROR("[android] send");
        close(sock);
        return -1;
    }

    char ret = 0;

    if (recv(sock, &ret, 1, 0) == -1) {
        ERROR("[android] recv");
        close(sock);
        return -1;
    }

    close(sock);
    return ret;
}
