/*
 * Copyright (C) 2013-2020 Canonical, Ltd.
 *
 * This program 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 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * This code is a complete clean re-write of the stress tool by
 * Colin Ian King <colin.king@canonical.com> and attempts to be
 * backwardly compatible with the stress tool by Amos Waterland
 * <apw@rossby.metr.ou.edu> but has more stress tests and more
 * functionality.
 *
 */
#include "stress-ng.h"

#if !defined(SOL_UDP)
#define SOL_UDP 	(17)
#endif
#define PACKET_SIZE	(2048)

static const stress_help_t help[] = {
	{ NULL, "rawpkt N",		"start N workers exercising raw packets" },
	{ NULL,	"rawpkt-ops N",		"stop after N raw packet bogo operations" },
	{ NULL,	"rawpkt-port P",	"use raw packet ports P to P + number of workers - 1" },
	{ NULL,	NULL,			NULL }
};

/*
 *  stress_rawpkt_supported()
 *      check if we can run this as root
 */
static int stress_rawpkt_supported(const char *name)
{
	if (!stress_check_capability(SHIM_CAP_NET_RAW)) {
		pr_inf("%s stressor will be skipped, "
			"need to be running with CAP_NET_RAW "
			"rights for this stressor\n", name);
		return -1;
	}
	return 0;
}

/*
 *  stress_set_rawpkt_port()
 *	set port to use
 */
static int stress_set_port(const char *opt)
{
	int port;

	stress_set_net_port("rawpkt-port", opt,
		MIN_RAWPKT_PORT, MAX_RAWPKT_PORT - STRESS_PROCS_MAX,
		&port);
	return stress_set_setting("rawpkt-port", TYPE_ID_INT, &port);
}

static const stress_opt_set_func_t opt_set_funcs[] = {
	{ OPT_rawpkt_port,	stress_set_port },
	{ 0,			NULL }
};

#if defined(HAVE_LINUX_UDP_H) &&	\
    defined(HAVE_LINUX_IF_PACKET_H)
/*
 *  stress_rawpkt_getsockopts()
 *	fetch some SOL_PACKET specific stats, ignore failures
 *	just exercise the interface.
 */
static void stress_rawpkt_getsockopts(const int fd)
{
#if defined(PACKET_STATISTICS)
	{
		struct tpacket_stats stats;
		socklen_t len = sizeof(stats);

		(void)getsockopt(fd, SOL_PACKET, PACKET_STATISTICS, &stats, &len);
	}
#endif
#if defined(PACKET_AUXDATA)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_AUXDATA, &val, &len);
	}
#endif
#if defined(PACKET_ORIGDEV)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_ORIGDEV, &val, &len);
	}
#endif
#if defined(PACKET_VNET_HDR)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_VNET_HDR, &val, &len);
	}
#endif
#if defined(PACKET_VERSION)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_VERSION, &val, &len);
	}
#endif
#if defined(PACKET_HDRLEN)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_HDRLEN, &val, &len);
	}
#endif
#if defined(PACKET_RESERVE)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_RESERVE, &val, &len);
	}
#endif
#if defined(PACKET_LOSS)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_LOSS, &val, &len);
	}
#endif
#if defined(PACKET_TIMESTAMP)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_TIMESTAMP, &val, &len);
	}
#endif
#if defined(PACKET_FANOUT)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_FANOUT, &val, &len);
	}
#endif
#if defined(PACKET_IGNORE_OUTGOING)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_IGNORE_OUTGOING, &val, &len);
	}
#endif
#if defined(PACKET_ROLLOVER_STATS)
	{
		struct tpacket_rollover_stats rstats;
		socklen_t len = sizeof(rstats);

		(void)getsockopt(fd, SOL_PACKET, PACKET_ROLLOVER_STATS, &rstats, &len);
	}
#endif
#if defined(PACKET_TX_HAS_OFF)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_TX_HAS_OFF, &val, &len);
	}
#endif
#if defined(PACKET_QDISC_BYPASS)
	{
		int val;
		socklen_t len = sizeof(val);

		(void)getsockopt(fd, SOL_PACKET, PACKET_QDISC_BYPASS, &val, &len);
	}
#endif
}

/*
 *  stress_rawpkt_client()
 *	client sender
 */
static void stress_rawpkt_client(
	const stress_args_t *args,
	struct ifreq *hwaddr,
	struct ifreq *ifaddr,
	struct ifreq *idx,
	const pid_t ppid,
	const int port)
{
	int rc = EXIT_FAILURE;
	uint16_t id = 12345;
	char buf[PACKET_SIZE];
	struct ethhdr *eth = (struct ethhdr *)buf;
	struct iphdr *ip = (struct iphdr *)(buf + sizeof(struct ethhdr));
	struct udphdr *udp = (struct udphdr *)(buf + sizeof(struct ethhdr) + sizeof(struct iphdr));
	struct sockaddr_ll sadr;
	int fd;

	(void)setpgid(0, g_pgrp);
	stress_parent_died_alarm();
	(void)sched_settings_apply(true);

	(void)memset(buf, 0, sizeof(buf));

	(void)memcpy(eth->h_dest, hwaddr->ifr_addr.sa_data, sizeof(eth->h_dest));
	(void)memcpy(eth->h_source, hwaddr->ifr_addr.sa_data, sizeof(eth->h_dest));
	eth->h_proto = htons(ETH_P_IP);

	ip->ihl = 5;		/* Header length in 32 bit words */
	ip->version = 4;	/* IPv4 */
	ip->tos = 0;
	ip->tot_len = sizeof(struct iphdr) + sizeof(struct udphdr);
	ip->ttl = 16;  		/* Not too many hops! */
	ip->protocol = SOL_UDP;	/* UDP protocol */
	ip->saddr = inet_addr(inet_ntoa((((struct sockaddr_in *)&(ifaddr->ifr_addr))->sin_addr)));
	ip->daddr = ip->saddr;

	udp->source = htons(port);
	udp->dest = htons(port);
	udp->len = htons(sizeof(struct udphdr));

	sadr.sll_ifindex = idx->ifr_ifindex;
	sadr.sll_halen = ETH_ALEN;
	(void)memcpy(&sadr.sll_addr, eth->h_dest, sizeof(eth->h_dest));

	if ((fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) < 0) {
		pr_fail("%s: socket failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		goto err;
	}

	do {
		ssize_t n;

		ip->id = htons(id++);
		ip->check = stress_ip_checksum((uint16_t *)ip, sizeof(struct iphdr) + sizeof(struct udphdr));

		n = sendto(fd, buf, sizeof(struct ethhdr) + ip->tot_len, 0, (struct sockaddr *)&sadr, sizeof(sadr));
		if (n < 0) {
			pr_err("%s: raw socket sendto failed on port %d, errno=%d (%s)\n",
				args->name, port, errno, strerror(errno));
		}
#if defined(SIOCOUTQ)
			/* Occasionally exercise SIOCOUTQ */
			if ((id & 0xff) == 0) {
				int ret, queued;

				ret = ioctl(fd, SIOCOUTQ, &queued);
				(void)ret;
			}
#endif
	} while (keep_stressing());

	stress_rawpkt_getsockopts(fd);
	(void)close(fd);

	rc = EXIT_SUCCESS;

err:
	/* Inform parent we're all done */
	(void)kill(ppid, SIGALRM);
	_exit(rc);
}

/*
 *  stress_rawpkt_server()
 *	server reader
 */
static int stress_rawpkt_server(
	const stress_args_t *args,
	struct ifreq *ifaddr,
	const int port)
{
	int fd;
	int rc = EXIT_SUCCESS;
	char buf[PACKET_SIZE];
	struct ethhdr *eth = (struct ethhdr *)buf;
	const struct iphdr *ip = (struct iphdr *)(buf + sizeof(struct ethhdr));
	const struct udphdr *udp = (struct udphdr *)(buf + sizeof(struct ethhdr) + sizeof(struct iphdr));
	struct sockaddr saddr;
	int saddr_len = sizeof(saddr);
	const uint32_t addr = inet_addr(inet_ntoa((((struct sockaddr_in *)&(ifaddr->ifr_addr))->sin_addr)));
	uint64_t all_pkts = 0;

	if (stress_sig_stop_stressing(args->name, SIGALRM) < 0) {
		rc = EXIT_FAILURE;
		goto die;
	}
	if ((fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL))) < 0) {
		rc = exit_status(errno);
		pr_fail("%s: socket failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		goto die;
	}

	do {
		ssize_t n;

		n = recvfrom(fd, buf, sizeof(buf), 0, &saddr, (socklen_t *)&saddr_len);
		if (n > 0) {
			all_pkts++;
			if ((eth->h_proto == htons(ETH_P_IP)) &&
			    (ip->saddr == addr) &&
			    (ip->protocol == SOL_UDP) &&
			    (ntohs(udp->source) == port)) {
				inc_counter(args);
			}
		}
#if defined(SIOCINQ)
		/* Exercise SIOCINQ */
		if ((all_pkts & 0xff) == 0) {
			int ret, queued;

			ret = ioctl(fd, SIOCINQ, &queued);
			(void)ret;
		}
#endif
	} while (keep_stressing());

	stress_rawpkt_getsockopts(fd);
	(void)close(fd);
die:
	pr_dbg("%s: %" PRIu64 " packets sent, %" PRIu64 " packets received\n", args->name, get_counter(args), all_pkts);

	return rc;
}

static void stress_sock_sigpipe_handler(int signum)
{
	(void)signum;

	keep_stressing_set_flag(false);
}

/*
 *  stress_rawpkt
 *	stress raw socket I/O UDP packet send/receive
 */
static int stress_rawpkt(const stress_args_t *args)
{
	pid_t pid;
	int port = DEFAULT_RAWPKT_PORT;
	int fd, rc = EXIT_FAILURE;
	struct ifreq hwaddr, ifaddr, idx;

	(void)stress_get_setting("rawpkt-port", &port);

	pr_dbg("%s: process [%d] using socket port %d\n",
		args->name, (int)args->pid, port + args->instance);

	if (stress_sighandler(args->name, SIGPIPE, stress_sock_sigpipe_handler, NULL) < 0)
		return EXIT_NO_RESOURCE;

	if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
		pr_fail("%s: socket failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		return EXIT_FAILURE;
	}
	(void)memset(&hwaddr, 0, sizeof(hwaddr));
	(void)shim_strlcpy(hwaddr.ifr_name, "lo", sizeof(hwaddr.ifr_name));
	if (ioctl(fd, SIOCGIFHWADDR, &hwaddr) < 0) {
		pr_fail("%s: ioctl SIOCGIFHWADDR on lo failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		(void)close(fd);
		return EXIT_FAILURE;
	}

	(void)memset(&ifaddr, 0, sizeof(ifaddr));
	(void)shim_strlcpy(ifaddr.ifr_name, "lo", sizeof(ifaddr.ifr_name));
	if (ioctl(fd, SIOCGIFADDR, &ifaddr) < 0) {
		pr_fail("%s: ioctl SIOCGIFADDR on lo failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		(void)close(fd);
		return EXIT_FAILURE;
	}

	(void)memset(&idx, 0, sizeof(idx));
	(void)shim_strlcpy(idx.ifr_name, "lo", sizeof(idx.ifr_name));
	if (ioctl(fd, SIOCGIFINDEX, &idx) < 0) {
		pr_fail("%s: ioctl SIOCGIFINDEX on lo failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		(void)close(fd);
		return EXIT_FAILURE;
	}
	(void)close(fd);
again:
	pid = fork();
	if (pid < 0) {
		if (keep_stressing_flag() && (errno == EAGAIN))
			goto again;
		pr_fail("%s: fork failed, errno=%d (%s)\n",
			args->name, errno, strerror(errno));
		return rc;
	} else if (pid == 0) {
		stress_rawpkt_client(args, &hwaddr, &ifaddr, &idx, args->pid, port);
		_exit(EXIT_SUCCESS);
	} else {
		int status;

		rc = stress_rawpkt_server(args, &ifaddr, port);
		(void)kill(pid, SIGKILL);
		(void)shim_waitpid(pid, &status, 0);
	}
	return rc;
}

stressor_info_t stress_rawpkt_info = {
	.stressor = stress_rawpkt,
	.class = CLASS_NETWORK | CLASS_OS,
	.opt_set_funcs = opt_set_funcs,
	.supported = stress_rawpkt_supported,
	.help = help
};
#else
stressor_info_t stress_rawpkt_info = {
	.stressor = stress_not_implemented,
	.class = CLASS_NETWORK | CLASS_OS,
	.opt_set_funcs = opt_set_funcs,
	.supported = stress_rawpkt_supported,
	.help = help
};
#endif
