linuxptp/sk.c
David Mirabito via Linuxptp-devel 6b61ba29c7 Avoid fault when receiving zero length packets
The manpage for recvmsg says -1 will be returned on error, Zero indicates an
"orderly shutdown", presumably only in case of stream sockets.
Further, UNIX Network Programming, Vol 1 says ".. a return value of 0 from
recvfrom is acceptable for a datagram protocol"

Such packets have been observed in the wild, aimed at PTP's multicast
address and port, possibly related to malformed management queries.

Patch to properly check return from recvmesg and not trigger the fault
codepath. Instead, such packets are treated as "Bad Message" the same as
non-zero but still too-short UDP payloads.

Signed-off-by: David Mirabito <davidjm@arista.com>
2019-03-25 06:25:07 -07:00

530 lines
12 KiB
C

/**
* @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;
enum hwts_filter_mode sk_hwts_filter_mode = HWTS_FILTER_NORMAL;
/* private methods */
static void init_ifreq(struct ifreq *ifreq, struct hwtstamp_config *cfg,
const char *device)
{
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;
}
static int hwts_init(int fd, const char *device, int rx_filter,
int rx_filter2, int tx_type)
{
struct ifreq ifreq;
struct hwtstamp_config cfg;
int err;
init_ifreq(&ifreq, &cfg, device);
switch (sk_hwts_filter_mode) {
case HWTS_FILTER_CHECK:
err = ioctl(fd, SIOCGHWTSTAMP, &ifreq);
if (err < 0) {
pr_err("ioctl SIOCGHWTSTAMP failed: %m");
return err;
}
break;
case HWTS_FILTER_FULL:
cfg.tx_type = tx_type;
cfg.rx_filter = HWTSTAMP_FILTER_ALL;
err = ioctl(fd, SIOCSHWTSTAMP, &ifreq);
if (err < 0) {
pr_err("ioctl SIOCSHWTSTAMP failed: %m");
return err;
}
break;
case HWTS_FILTER_NORMAL:
cfg.tx_type = tx_type;
cfg.rx_filter = rx_filter;
err = ioctl(fd, SIOCSHWTSTAMP, &ifreq);
if (err < 0) {
pr_info("driver rejected most general HWTSTAMP filter");
init_ifreq(&ifreq, &cfg, device);
cfg.tx_type = tx_type;
cfg.rx_filter = rx_filter2;
err = ioctl(fd, SIOCSHWTSTAMP, &ifreq);
if (err < 0) {
pr_err("ioctl SIOCSHWTSTAMP failed: %m");
return err;
}
}
break;
}
if (cfg.tx_type != tx_type ||
(cfg.rx_filter != rx_filter &&
cfg.rx_filter != rx_filter2 &&
cfg.rx_filter != HWTSTAMP_FILTER_ALL)) {
pr_debug("tx_type %d not %d", cfg.tx_type, tx_type);
pr_debug("rx_filter %d not %d or %d", cfg.rx_filter, rx_filter,
rx_filter2);
pr_err("The current filter does not match the required");
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 < 0)
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, int family, uint8_t dscp)
{
int level, optname, tos;
socklen_t tos_len;
switch (family) {
case AF_INET:
level = IPPROTO_IP;
optname = IP_TOS;
break;
case AF_INET6:
level = IPPROTO_IPV6;
optname = IPV6_TCLASS;
break;
default:
return -1;
}
tos_len = sizeof(tos);
if (getsockopt(fd, level, optname, &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, level, optname, &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, filter2, tx_type);
if (err)
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;
}