// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 *  BlueZ - Bluetooth protocol stack for Linux
 *
 *  Copyright (C) 2000-2001  Qualcomm Incorporated
 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2002-2010  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#define _GNU_SOURCE
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include <signal.h>
#include <sys/time.h>
#include <poll.h>
#include <sys/socket.h>

#include "lib/bluetooth.h"
#include "lib/hci.h"
#include "lib/hci_lib.h"
#include "lib/l2cap.h"

/* Defaults */
static bdaddr_t bdaddr;
static int size    = 44;
static int ident   = 200;
static int delay   = 1;
static int count   = -1;
static int timeout = 10;
static int reverse = 0;
static int verify = 0;

/* Stats */
static int sent_pkt = 0;
static int recv_pkt = 0;

static float tv2fl(struct timeval tv)
{
	return (float)(tv.tv_sec*1000.0) + (float)(tv.tv_usec/1000.0);
}

static void stat(int sig)
{
	int loss = sent_pkt ? (float)((sent_pkt-recv_pkt)/(sent_pkt/100.0)) : 0;
	printf("%d sent, %d received, %d%% loss\n", sent_pkt, recv_pkt, loss);
	exit(0);
}

static void ping(char *svr)
{
	struct sigaction sa;
	struct sockaddr_l2 addr;
	socklen_t optlen;
	unsigned char *send_buf;
	unsigned char *recv_buf;
	char str[18];
	int i, sk, lost;
	uint8_t id;

	memset(&sa, 0, sizeof(sa));
	sa.sa_handler = stat;
	sigaction(SIGINT, &sa, NULL);

	send_buf = malloc(L2CAP_CMD_HDR_SIZE + size);
	recv_buf = malloc(L2CAP_CMD_HDR_SIZE + size);
	if (!send_buf || !recv_buf) {
		perror("Can't allocate buffer");
		exit(1);
	}

	/* Create socket */
	sk = socket(PF_BLUETOOTH, SOCK_RAW, BTPROTO_L2CAP);
	if (sk < 0) {
		perror("Can't create socket");
		goto error;
	}

	/* Bind to local address */
	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	bacpy(&addr.l2_bdaddr, &bdaddr);

	if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
		perror("Can't bind socket");
		goto error;
	}

	/* Connect to remote device */
	memset(&addr, 0, sizeof(addr));
	addr.l2_family = AF_BLUETOOTH;
	str2ba(svr, &addr.l2_bdaddr);

	if (connect(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
		perror("Can't connect");
		goto error;
	}

	/* Get local address */
	memset(&addr, 0, sizeof(addr));
	optlen = sizeof(addr);

	if (getsockname(sk, (struct sockaddr *) &addr, &optlen) < 0) {
		perror("Can't get local address");
		goto error;
	}

	ba2str(&addr.l2_bdaddr, str);
	printf("Ping: %s from %s (data size %d) ...\n", svr, str, size);

	/* Initialize send buffer */
	for (i = 0; i < size; i++)
		send_buf[L2CAP_CMD_HDR_SIZE + i] = (i % 40) + 'A';

	id = ident;

	while (count == -1 || count-- > 0) {
		struct timeval tv_send, tv_recv, tv_diff;
		l2cap_cmd_hdr *send_cmd = (l2cap_cmd_hdr *) send_buf;
		l2cap_cmd_hdr *recv_cmd = (l2cap_cmd_hdr *) recv_buf;

		/* Build command header */
		send_cmd->ident = id;
		send_cmd->len   = htobs(size);

		if (reverse)
			send_cmd->code = L2CAP_ECHO_RSP;
		else
			send_cmd->code = L2CAP_ECHO_REQ;

		gettimeofday(&tv_send, NULL);

		/* Send Echo Command */
		if (send(sk, send_buf, L2CAP_CMD_HDR_SIZE + size, 0) <= 0) {
			perror("Send failed");
			goto error;
		}

		/* Wait for Echo Response */
		lost = 0;
		while (1) {
			struct pollfd pf[1];
			int err;

			pf[0].fd = sk;
			pf[0].events = POLLIN;

			if ((err = poll(pf, 1, timeout * 1000)) < 0) {
				perror("Poll failed");
				goto error;
			}

			if (!err) {
				lost = 1;
				break;
			}

			if ((err = recv(sk, recv_buf, L2CAP_CMD_HDR_SIZE + size, 0)) < 0) {
				perror("Recv failed");
				goto error;
			}

			if (!err){
				printf("Disconnected\n");
				goto error;
			}

			recv_cmd->len = btohs(recv_cmd->len);

			/* Check for our id */
			if (recv_cmd->ident != id)
				continue;

			/* Check type */
			if (!reverse && recv_cmd->code == L2CAP_ECHO_RSP)
				break;

			if (recv_cmd->code == L2CAP_COMMAND_REJ) {
				printf("Peer doesn't support Echo packets\n");
				goto error;
			}

		}
		sent_pkt++;

		if (!lost) {
			recv_pkt++;

			gettimeofday(&tv_recv, NULL);
			timersub(&tv_recv, &tv_send, &tv_diff);

			if (verify) {
				/* Check payload length */
				if (recv_cmd->len != size) {
					fprintf(stderr, "Received %d bytes, expected %d\n",
						   recv_cmd->len, size);
					goto error;
				}

				/* Check payload */
				if (memcmp(&send_buf[L2CAP_CMD_HDR_SIZE],
						   &recv_buf[L2CAP_CMD_HDR_SIZE], size)) {
					fprintf(stderr, "Response payload different.\n");
					goto error;
				}
			}

			printf("%d bytes from %s id %d time %.2fms\n", recv_cmd->len, svr,
				   id - ident, tv2fl(tv_diff));

			if (delay)
				sleep(delay);
		} else {
			printf("no response from %s: id %d\n", svr, id - ident);
		}

		if (++id > 254)
			id = ident;
	}
	stat(0);
	free(send_buf);
	free(recv_buf);
	return;

error:
	close(sk);
	free(send_buf);
	free(recv_buf);
	exit(1);
}

static void usage(void)
{
	printf("l2ping - L2CAP ping\n");
	printf("Usage:\n");
	printf("\tl2ping [-i device] [-s size] [-c count] [-t timeout] [-d delay] [-f] [-r] [-v] <bdaddr>\n");
	printf("\t-f  Flood ping (delay = 0)\n");
	printf("\t-r  Reverse ping\n");
	printf("\t-v  Verify request and response payload\n");
}

int main(int argc, char *argv[])
{
	int opt;

	/* Default options */
	bacpy(&bdaddr, BDADDR_ANY);

	while ((opt=getopt(argc,argv,"i:d:s:c:t:frv")) != EOF) {
		switch(opt) {
		case 'i':
			if (!strncasecmp(optarg, "hci", 3))
				hci_devba(atoi(optarg + 3), &bdaddr);
			else
				str2ba(optarg, &bdaddr);
			break;

		case 'd':
			delay = atoi(optarg);
			break;

		case 'f':
			/* Kinda flood ping */
			delay = 0;
			break;

		case 'r':
			/* Use responses instead of requests */
			reverse = 1;
			break;

		case 'v':
			verify = 1;
			break;

		case 'c':
			count = atoi(optarg);
			break;

		case 't':
			timeout = atoi(optarg);
			break;

		case 's':
			size = atoi(optarg);
			break;

		default:
			usage();
			exit(1);
		}
	}

	if (!(argc - optind)) {
		usage();
		exit(1);
	}

	ping(argv[optind]);

	return 0;
}