/**

 * @file sk.c

 * @brief Implements protocol independent socket methods.

 * @note Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>

 *

 * 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.

 */

#include <errno.h>

#include <time.h>

#include <linux/net_tstamp.h>

#include <linux/sockios.h>

#include <linux/ethtool.h>

#include <net/if.h>

#include <netinet/in.h>

#include <string.h>

#include <sys/ioctl.h>

#include <unistd.h>

#include <ifaddrs.h>

#include <stdlib.h>

#include <poll.h>

#include "address.h"

#include "ether.h"

#include "missing.h"

#include "print.h"

#include "sk.h"

/* globals */

int sk_tx_timeout = 1;

int sk_check_fupsync;

/* private methods */

static int hwts_init(int fd, const char *device, int rx_filter, int tx_type)

{

	struct ifreq ifreq;

	struct hwtstamp_config cfg, req;

	int err;

	memset(&ifreq, 0, sizeof(ifreq));

	memset(&cfg, 0, sizeof(cfg));

	strncpy(ifreq.ifr_name, device, sizeof(ifreq.ifr_name) - 1);

	ifreq.ifr_data = (void *) &cfg;

	cfg.tx_type    = tx_type;

	cfg.rx_filter  = rx_filter;

	req = cfg;

	err = ioctl(fd, SIOCSHWTSTAMP, &ifreq);

	if (err < 0)

		return err;

	if (memcmp(&cfg, &req, sizeof(cfg))) {

		pr_debug("driver changed our HWTSTAMP options");

		pr_debug("tx_type   %d not %d", cfg.tx_type, req.tx_type);

		pr_debug("rx_filter %d not %d", cfg.rx_filter, req.rx_filter);

		if (cfg.tx_type != req.tx_type ||

		    (cfg.rx_filter != HWTSTAMP_FILTER_ALL &&

		     cfg.rx_filter != HWTSTAMP_FILTER_PTP_V2_EVENT)) {

			return -1;

		}

	}

	return 0;

}

/* public methods */

int sk_interface_fd(void)

{

	int fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);

	if (fd < 0) {

		pr_err("socket failed: %m");

		return -1;

	}

	return fd;

}

int sk_interface_index(int fd, const char *name)

{

	struct ifreq ifreq;

	int err;

	memset(&ifreq, 0, sizeof(ifreq));

	strncpy(ifreq.ifr_name, name, sizeof(ifreq.ifr_name) - 1);

	err = ioctl(fd, SIOCGIFINDEX, &ifreq);

	if (err < 0) {

		pr_err("ioctl SIOCGIFINDEX failed: %m");

		return err;

	}

	return ifreq.ifr_ifindex;

}

int sk_general_init(int fd)

{

	int on = sk_check_fupsync ? 1 : 0;

	if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPNS, &on, sizeof(on)) < 0) {

		pr_err("ioctl SO_TIMESTAMPNS failed: %m");

		return -1;

	}

	return 0;

}

int sk_get_ts_info(const char *name, struct sk_ts_info *sk_info)

{

#ifdef ETHTOOL_GET_TS_INFO

	struct ethtool_ts_info info;

	struct ifreq ifr;

	int fd, err;

	memset(&ifr, 0, sizeof(ifr));

	memset(&info, 0, sizeof(info));

	info.cmd = ETHTOOL_GET_TS_INFO;

	strncpy(ifr.ifr_name, name, IFNAMSIZ - 1);

	ifr.ifr_data = (char *) &info;

	fd = socket(AF_INET, SOCK_DGRAM, 0);

	if (fd < 0) {

		pr_err("socket failed: %m");

		goto failed;

	}

	err = ioctl(fd, SIOCETHTOOL, &ifr);

	if (err < 0) {

		pr_err("ioctl SIOCETHTOOL failed: %m");

		close(fd);

		goto failed;

	}

	close(fd);

	/* copy the necessary data to sk_info */

	memset(sk_info, 0, sizeof(struct sk_ts_info));

	sk_info->valid = 1;

	sk_info->phc_index = info.phc_index;

	sk_info->so_timestamping = info.so_timestamping;

	sk_info->tx_types = info.tx_types;

	sk_info->rx_filters = info.rx_filters;

	return 0;

failed:

#endif

	/* clear data and ensure it is not marked valid */

	memset(sk_info, 0, sizeof(struct sk_ts_info));

	return -1;

}

static int sk_interface_guidaddr(const char *name, unsigned char *guid)

{

	char file_name[64], buf[64], addr[8];

	FILE *f;

	char *err;

	int res;

	snprintf(file_name, sizeof buf, "/sys/class/net/%s/address", name);

	f = fopen(file_name, "r");

	if (!f) {

		pr_err("failed to open %s: %m", buf);

		return -1;

	}

	/* Set the file position to the beginning of the GUID */

	res = fseek(f, GUID_OFFSET, SEEK_SET);

	if (res) {

		pr_err("fseek failed: %m");

		goto error;

	}

	err = fgets(buf, sizeof buf, f);

	if (err == NULL) {

		pr_err("fseek failed: %m");

		goto error;

	}

	res = sscanf(buf, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",

			   &addr[0], &addr[1], &addr[2], &addr[3],

			   &addr[4], &addr[5], &addr[6], &addr[7]);

	if (res != GUID_LEN) {

		pr_err("sscanf failed: %m");

		goto error;

	}

	memcpy(guid, addr, GUID_LEN);

	fclose(f);

	return 0;

error:

	fclose(f);

	return -1;

}

int sk_interface_macaddr(const char *name, struct address *mac)

{

	struct ifreq ifreq;

	int err, fd, type;

	memset(&ifreq, 0, sizeof(ifreq));

	strncpy(ifreq.ifr_name, name, sizeof(ifreq.ifr_name) - 1);

	fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);

	if (fd < 0) {

		pr_err("socket failed: %m");

		return -1;

	}

	err = ioctl(fd, SIOCGIFHWADDR, &ifreq);

	if (err < 0) {

		pr_err("ioctl SIOCGIFHWADDR failed: %m");

		close(fd);

		return -1;

	}

	close(fd);

	/* Get interface type */

	type = ifreq.ifr_hwaddr.sa_family;

	switch (type) {

		case ARPHRD_INFINIBAND:

			err = sk_interface_guidaddr(name, mac->sll.sll_addr);

			if (err) {

				pr_err("fail to get address using sysfs: %m");

				return -1;

			}

			mac->sll.sll_halen = EUI64;

			break;

		default:

			memcpy(mac->sll.sll_addr, &ifreq.ifr_hwaddr.sa_data, MAC_LEN);

			mac->sll.sll_halen = EUI48;

	}

	mac->sll.sll_family = AF_PACKET;

	mac->len = sizeof(mac->sll);

	return 0;

}

int sk_interface_addr(const char *name, int family, struct address *addr)

{

	struct ifaddrs *ifaddr, *i;

	int result = -1;

	if (getifaddrs(&ifaddr) == -1) {

		pr_err("getifaddrs failed: %m");

		return -1;

	}

	for (i = ifaddr; i; i = i->ifa_next) {

		if (i->ifa_addr && family == i->ifa_addr->sa_family &&

			strcmp(name, i->ifa_name) == 0)

		{

			switch (family) {

			case AF_INET:

				addr->len = sizeof(addr->sin);

				memcpy(&addr->sin, i->ifa_addr, addr->len);

				break;

			case AF_INET6:

				addr->len = sizeof(addr->sin6);

				memcpy(&addr->sin6, i->ifa_addr, addr->len);

				break;

			default:

				continue;

			}

			result = 0;

			break;

		}

	}

	freeifaddrs(ifaddr);

	return result;

}

static short sk_events = POLLPRI;

static short sk_revents = POLLPRI;

int sk_receive(int fd, void *buf, int buflen,

	       struct address *addr, struct hw_timestamp *hwts, int flags)

{

	char control[256];

	int cnt = 0, res = 0, level, type;

	struct cmsghdr *cm;

	struct iovec iov = { buf, buflen };

	struct msghdr msg;

	struct timespec *sw, *ts = NULL;

	memset(control, 0, sizeof(control));

	memset(&msg, 0, sizeof(msg));

	if (addr) {

		msg.msg_name = &addr->ss;

		msg.msg_namelen = sizeof(addr->ss);

	}

	msg.msg_iov = &iov;

	msg.msg_iovlen = 1;

	msg.msg_control = control;

	msg.msg_controllen = sizeof(control);

	if (flags == MSG_ERRQUEUE) {

		struct pollfd pfd = { fd, sk_events, 0 };

		res = poll(&pfd, 1, sk_tx_timeout);

		if (res < 1) {

			pr_err(res ? "poll for tx timestamp failed: %m" :

			             "timed out while polling for tx timestamp");

			pr_err("increasing tx_timestamp_timeout may correct "

			       "this issue, but it is likely caused by a driver bug");

			return res;

		} else if (!(pfd.revents & sk_revents)) {

			pr_err("poll for tx timestamp woke up on non ERR event");

			return -1;

		}

	}

	cnt = recvmsg(fd, &msg, flags);

	if (cnt < 1)

		pr_err("recvmsg%sfailed: %m",

		       flags == MSG_ERRQUEUE ? " tx timestamp " : " ");

	for (cm = CMSG_FIRSTHDR(&msg;; cm != NULL; cm = CMSG_NXTHDR(&msg, cm)) {

		level = cm->cmsg_level;

		type  = cm->cmsg_type;

		if (SOL_SOCKET == level && SO_TIMESTAMPING == type) {

			if (cm->cmsg_len < sizeof(*ts) * 3) {

				pr_warning("short SO_TIMESTAMPING message");

				return -1;

			}

			ts = (struct timespec *) CMSG_DATA(cm);

		}

		if (SOL_SOCKET == level && SO_TIMESTAMPNS == type) {

			if (cm->cmsg_len < sizeof(*sw)) {

				pr_warning("short SO_TIMESTAMPNS message");

				return -1;

			}

			sw = (struct timespec *) CMSG_DATA(cm);

			hwts->sw = timespec_to_tmv(*sw);

		}

	}

	if (addr)

		addr->len = msg.msg_namelen;

	if (!ts) {

		memset(&hwts->ts, 0, sizeof(hwts->ts));

		return cnt;

	}

	switch (hwts->type) {

	case TS_SOFTWARE:

		hwts->ts = timespec_to_tmv(ts[0]);

		break;

	case TS_HARDWARE:

	case TS_ONESTEP:

	case TS_P2P1STEP:

		hwts->ts = timespec_to_tmv(ts[2]);

		break;

	case TS_LEGACY_HW:

		hwts->ts = timespec_to_tmv(ts[1]);

		break;

	}

	return cnt;

}

int sk_set_priority(int fd, uint8_t dscp)

{

	int tos;

	socklen_t tos_len;

	tos_len = sizeof(tos);

	if (getsockopt(fd, SOL_IP, IP_TOS, &tos, &tos_len) < 0) {

		tos = 0;

	}

	/* clear old DSCP value */

	tos &= ~0xFC;

	/* set new DSCP value */

	tos |= dscp<<2;

	tos_len = sizeof(tos);

	if (setsockopt(fd, SOL_IP, IP_TOS, &tos, tos_len) < 0) {

		return -1;

	}

	return 0;

}

int sk_timestamping_init(int fd, const char *device, enum timestamp_type type,

			 enum transport_type transport)

{

	int err, filter1, filter2 = 0, flags, tx_type = HWTSTAMP_TX_ON;

	switch (type) {

	case TS_SOFTWARE:

		flags = SOF_TIMESTAMPING_TX_SOFTWARE |

			SOF_TIMESTAMPING_RX_SOFTWARE |

			SOF_TIMESTAMPING_SOFTWARE;

		break;

	case TS_HARDWARE:

	case TS_ONESTEP:

	case TS_P2P1STEP:

		flags = SOF_TIMESTAMPING_TX_HARDWARE |

			SOF_TIMESTAMPING_RX_HARDWARE |

			SOF_TIMESTAMPING_RAW_HARDWARE;

		break;

	case TS_LEGACY_HW:

		flags = SOF_TIMESTAMPING_TX_HARDWARE |

			SOF_TIMESTAMPING_RX_HARDWARE |

			SOF_TIMESTAMPING_SYS_HARDWARE;

		break;

	default:

		return -1;

	}

	if (type != TS_SOFTWARE) {

		filter1 = HWTSTAMP_FILTER_PTP_V2_EVENT;

		switch (type) {

		case TS_SOFTWARE:

			tx_type = HWTSTAMP_TX_OFF;

			break;

		case TS_HARDWARE:

		case TS_LEGACY_HW:

			tx_type = HWTSTAMP_TX_ON;

			break;

		case TS_ONESTEP:

			tx_type = HWTSTAMP_TX_ONESTEP_SYNC;

			break;

		case TS_P2P1STEP:

			tx_type = HWTSTAMP_TX_ONESTEP_P2P;

			break;

		}

		switch (transport) {

		case TRANS_UDP_IPV4:

		case TRANS_UDP_IPV6:

			filter2 = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;

			break;

		case TRANS_IEEE_802_3:

			filter2 = HWTSTAMP_FILTER_PTP_V2_L2_EVENT;

			break;

		case TRANS_DEVICENET:

		case TRANS_CONTROLNET:

		case TRANS_PROFINET:

		case TRANS_UDS:

			return -1;

		}

		err = hwts_init(fd, device, filter1, tx_type);

		if (err) {

			pr_info("driver rejected most general HWTSTAMP filter");

			err = hwts_init(fd, device, filter2, tx_type);

			if (err) {

				pr_err("ioctl SIOCSHWTSTAMP failed: %m");

				return err;

			}

		}

	}

	if (setsockopt(fd, SOL_SOCKET, SO_TIMESTAMPING,

		       &flags, sizeof(flags)) < 0) {

		pr_err("ioctl SO_TIMESTAMPING failed: %m");

		return -1;

	}

	flags = 1;

	if (setsockopt(fd, SOL_SOCKET, SO_SELECT_ERR_QUEUE,

		       &flags, sizeof(flags)) < 0) {

		pr_warning("%s: SO_SELECT_ERR_QUEUE: %m", device);

		sk_events = 0;

		sk_revents = POLLERR;

	}

	/* Enable the sk_check_fupsync option, perhaps. */

	if (sk_general_init(fd)) {

		return -1;

	}

	return 0;

}