udev: Add module for checking interface renaming actions
This commit is contained in:
Marcel Holtmann
parent
88d3261bc2
commit
be3f6a2ca0
|
|
@ -265,6 +265,7 @@ src_iwd_SOURCES = src/main.c linux/nl80211.h src/iwd.h src/missing.h \
|
|||
src/dpp-util.h src/dpp-util.c \
|
||||
src/json.h src/json.c \
|
||||
src/dpp.c \
|
||||
src/udev.c \
|
||||
$(eap_sources) \
|
||||
$(builtin_sources)
|
||||
|
||||
|
|
|
|||
|
|
@ -0,0 +1,285 @@
|
|||
/*
|
||||
*
|
||||
* Wireless daemon for Linux
|
||||
*
|
||||
* Copyright (C) 2024 Intel Corporation. All rights reserved.
|
||||
*
|
||||
* This library is free software; you can redistribute it and/or
|
||||
* modify it under the terms of the GNU Lesser General Public
|
||||
* License as published by the Free Software Foundation; either
|
||||
* version 2.1 of the License, or (at your option) any later version.
|
||||
*
|
||||
* This library 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
|
||||
* Lesser General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU Lesser General Public
|
||||
* License along with this library; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*
|
||||
*/
|
||||
|
||||
#ifdef HAVE_CONFIG_H
|
||||
#include <config.h>
|
||||
#endif
|
||||
|
||||
#include <errno.h>
|
||||
#include <unistd.h>
|
||||
#include <sys/socket.h>
|
||||
#include <linux/netlink.h>
|
||||
#include <linux/filter.h>
|
||||
#include <ell/ell.h>
|
||||
|
||||
#include "src/module.h"
|
||||
|
||||
static void receive_props(const void *buf, uint32_t len)
|
||||
{
|
||||
const char *action = NULL;
|
||||
const char *interface = NULL;
|
||||
const char *ifindex = NULL;
|
||||
|
||||
while (len > 0) {
|
||||
const char *s = buf;
|
||||
size_t l = strlen(s);
|
||||
const char *t;
|
||||
|
||||
if (l < 2)
|
||||
break;
|
||||
|
||||
t = strchr(s, '=');
|
||||
if (t) {
|
||||
size_t p = t - s;
|
||||
|
||||
if (!strncmp(s, "ACTION", p))
|
||||
action = t + 1;
|
||||
else if (!strncmp(s, "INTERFACE", p))
|
||||
interface = t + 1;
|
||||
else if (!strncmp(s, "IFINDEX", p))
|
||||
ifindex = t + 1;
|
||||
}
|
||||
|
||||
buf += l + 1;
|
||||
len -= l + 1;
|
||||
}
|
||||
|
||||
if (action && !strcmp(action, "add"))
|
||||
l_info("udev interface=%s ifindex=%s", interface, ifindex);
|
||||
}
|
||||
|
||||
static struct l_io *udev_io;
|
||||
|
||||
static int create_socket(uint32_t *pid)
|
||||
{
|
||||
struct sockaddr_nl addr;
|
||||
socklen_t addrlen = sizeof(addr);
|
||||
int fd, pktinfo = 1;
|
||||
|
||||
fd = socket(PF_NETLINK, SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK,
|
||||
NETLINK_KOBJECT_UEVENT);
|
||||
if (fd < 0)
|
||||
return -1;
|
||||
|
||||
memset(&addr, 0, sizeof(addr));
|
||||
addr.nl_family = AF_NETLINK;
|
||||
|
||||
if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
|
||||
close(fd);
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (getsockname(fd, (struct sockaddr *) &addr, &addrlen) < 0) {
|
||||
close(fd);
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (setsockopt(fd, SOL_NETLINK, NETLINK_PKTINFO,
|
||||
&pktinfo, sizeof(pktinfo)) < 0) {
|
||||
close(fd);
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (pid)
|
||||
*pid = addr.nl_pid;
|
||||
|
||||
return fd;
|
||||
}
|
||||
|
||||
static struct sock_filter subsys_filter[] = {
|
||||
{ 0x20, 0, 0, 0x00000008 }, /* ldw #magic */
|
||||
{ 0x15, 0, 3, 0xfeedcafe }, /* jne #feedcafe, drop */
|
||||
{ 0x20, 0, 0, 0x00000018 }, /* ldw #subsys_hash */
|
||||
{ 0x15, 0, 1, 0xa74d3cc8 }, /* jne #net, drop */
|
||||
{ 0x06, 0, 0, 0xffffffff }, /* keep: ret #-1 */
|
||||
{ 0x06, 0, 0, 0000000000 }, /* drop: ret #0 */
|
||||
};
|
||||
|
||||
static const struct sock_fprog subsys_fprog = { .len = 6,
|
||||
.filter = subsys_filter };
|
||||
|
||||
static bool attach_filter(struct l_io *io)
|
||||
{
|
||||
int fd;
|
||||
|
||||
fd = l_io_get_fd(io);
|
||||
if (fd < 0)
|
||||
return false;
|
||||
|
||||
if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER,
|
||||
&subsys_fprog, sizeof(subsys_fprog)) < 0)
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool add_membership(struct l_io *io, uint32_t group)
|
||||
{
|
||||
int fd, value = group;
|
||||
|
||||
fd = l_io_get_fd(io);
|
||||
if (fd < 0)
|
||||
return false;
|
||||
|
||||
if (setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP,
|
||||
&value, sizeof(value)) < 0)
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool drop_membership(struct l_io *io, uint32_t group)
|
||||
{
|
||||
int fd, value = group;
|
||||
|
||||
fd = l_io_get_fd(io);
|
||||
if (fd < 0)
|
||||
return false;
|
||||
|
||||
if (setsockopt(fd, SOL_NETLINK, NETLINK_DROP_MEMBERSHIP,
|
||||
&value, sizeof(value)) < 0)
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static const uint8_t LIBUDEV_PREFIX[8] = { "libudev" };
|
||||
static uint32_t LIBUDEV_MAGIC = 0xfeedcafe;
|
||||
|
||||
struct udev_hdr {
|
||||
char prefix[8];
|
||||
uint32_t magic;
|
||||
uint32_t hdr_size;
|
||||
uint32_t props_off;
|
||||
uint32_t props_len;
|
||||
uint32_t flt_subsys_hash;
|
||||
uint32_t flt_devtype_hash;
|
||||
uint32_t flt_tag_bloom_hi;
|
||||
uint32_t flt_tag_bloom_lo;
|
||||
};
|
||||
|
||||
static void receive_msg(const void *buf, uint32_t len)
|
||||
{
|
||||
const struct udev_hdr *hdr = buf;
|
||||
|
||||
if (len < sizeof(struct udev_hdr))
|
||||
return;
|
||||
|
||||
if (memcmp(hdr->prefix, LIBUDEV_PREFIX, 8))
|
||||
return;
|
||||
|
||||
if (L_BE32_TO_CPU(hdr->magic) != LIBUDEV_MAGIC)
|
||||
return;
|
||||
|
||||
if (hdr->hdr_size > len)
|
||||
return;
|
||||
|
||||
if (hdr->props_off + hdr->props_len != len)
|
||||
return;
|
||||
|
||||
receive_props(buf + hdr->props_off, hdr->props_len);
|
||||
}
|
||||
|
||||
enum {
|
||||
GROUP_NONE,
|
||||
GROUP_KERNEL,
|
||||
GROUP_UDEV,
|
||||
};
|
||||
|
||||
static bool can_read_data(struct l_io *io, void *user_data)
|
||||
{
|
||||
struct cmsghdr *cmsg;
|
||||
struct msghdr msg;
|
||||
struct iovec iov;
|
||||
unsigned char buffer[4096];
|
||||
unsigned char control[32];
|
||||
uint32_t group = GROUP_NONE;
|
||||
ssize_t len;
|
||||
int fd;
|
||||
|
||||
memset(buffer, 0, sizeof(buffer));
|
||||
memset(control, 0, sizeof(control));
|
||||
|
||||
fd = l_io_get_fd(io);
|
||||
|
||||
iov.iov_base = buffer;
|
||||
iov.iov_len = sizeof(buffer);
|
||||
|
||||
memset(&msg, 0, sizeof(msg));
|
||||
msg.msg_iov = &iov;
|
||||
msg.msg_iovlen = 1;
|
||||
msg.msg_control = control;
|
||||
msg.msg_controllen = sizeof(control);
|
||||
|
||||
len = recvmsg(fd, &msg, 0);
|
||||
if (len < 0)
|
||||
return false;
|
||||
|
||||
for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
|
||||
cmsg = CMSG_NXTHDR(&msg, cmsg)) {
|
||||
struct nl_pktinfo *pktinfo;
|
||||
|
||||
if (cmsg->cmsg_level != SOL_NETLINK)
|
||||
continue;
|
||||
|
||||
if (cmsg->cmsg_type != NETLINK_PKTINFO)
|
||||
continue;
|
||||
|
||||
pktinfo = (void *) CMSG_DATA(cmsg);
|
||||
group = pktinfo->group;
|
||||
}
|
||||
|
||||
if (group == GROUP_UDEV)
|
||||
receive_msg(buffer, len);
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static int udev_init(void)
|
||||
{
|
||||
int fd;
|
||||
|
||||
l_debug("");
|
||||
|
||||
fd = create_socket(NULL);
|
||||
if (fd < 0)
|
||||
return -EIO;
|
||||
|
||||
udev_io = l_io_new(fd);
|
||||
l_io_set_close_on_destroy(udev_io, true);
|
||||
l_io_set_read_handler(udev_io, can_read_data, NULL, NULL);
|
||||
attach_filter(udev_io);
|
||||
add_membership(udev_io, GROUP_UDEV);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void udev_exit(void)
|
||||
{
|
||||
l_debug("");
|
||||
|
||||
drop_membership(udev_io, GROUP_UDEV);
|
||||
l_io_destroy(udev_io);
|
||||
}
|
||||
|
||||
IWD_MODULE(udev, udev_init, udev_exit);
|
||||
IWD_MODULE_DEPENDS(udev, netdev);
|
||||
Loading…
Reference in New Issue