340 lines
10 KiB
C
340 lines
10 KiB
C
/****************************************************************************
|
|
* netutils/netlib/netlib_getroute.c
|
|
*
|
|
* Copyright (C) 2019 Gregory Nutt. All rights reserved.
|
|
* Author: Gregory Nutt <gnutt@nuttx.org>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* 3. Neither the name NuttX nor the names of its contributors may be
|
|
* used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
|
|
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <sys/socket.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
|
|
#include <net/route.h>
|
|
#include <netpacket/netlink.h>
|
|
|
|
#include "netutils/netlib.h"
|
|
|
|
#if defined(CONFIG_NETLINK_ROUTE) && defined(CONFIG_NET_ROUTE)
|
|
|
|
/****************************************************************************
|
|
* Pre-processor definitions
|
|
****************************************************************************/
|
|
|
|
#define RXBUFFER_SIZE 64
|
|
|
|
/****************************************************************************
|
|
* Private Types
|
|
****************************************************************************/
|
|
|
|
struct netlib_sendto_request_s
|
|
{
|
|
struct nlmsghdr hdr;
|
|
struct rtgenmsg gen;
|
|
};
|
|
|
|
struct netlib_recvfrom_response_s
|
|
{
|
|
struct nlmsghdr hdr;
|
|
struct rtmsg rte;
|
|
struct rtattr attr;
|
|
|
|
/* Attribute data and additional attributes follow */
|
|
};
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
static int copy_address(FAR struct sockaddr_storage *dest, FAR void *src,
|
|
unsigned int addrlen, unsigned int maxaddr,
|
|
sa_family_t family)
|
|
{
|
|
DEBUGASSERT(addrlen <= maxaddr);
|
|
if (addrlen > maxaddr)
|
|
{
|
|
fprintf(stderr, "ERROR: Bad address length: %u\n", addrlen);
|
|
return -EIO;
|
|
}
|
|
|
|
dest->ss_family = family;
|
|
memcpy(dest->ss_data, src, addrlen);
|
|
return OK;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: netlib_get_route
|
|
*
|
|
* Description:
|
|
* Return a snapshot of the routing table for the selected address family.
|
|
*
|
|
* Parameters:
|
|
* rtelist - The location to store the list of devices.
|
|
* nentries - The size of the provided 'rtelist' in number of entries.
|
|
* The size of one entry is given by sizeof(struct rtentry);
|
|
* family - Address family. See AF_* definitions in sys/socket.h.
|
|
*
|
|
* Return:
|
|
* The number of routing table entries read is returned on success; a
|
|
* negated errno value is returned on failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
ssize_t netlib_get_route(FAR struct rtentry *rtelist,
|
|
unsigned int nentries, sa_family_t family)
|
|
{
|
|
struct netlib_sendto_request_s req;
|
|
struct sockaddr_nl addr;
|
|
static unsigned int seqno = 0;
|
|
unsigned int thiseq;
|
|
unsigned int maxaddr;
|
|
ssize_t nsent;
|
|
ssize_t nrecvd;
|
|
size_t ncopied = 0;
|
|
pid_t pid;
|
|
bool enddump;
|
|
int fd;
|
|
int ret;
|
|
|
|
union
|
|
{
|
|
char rxbuffer[RXBUFFER_SIZE];
|
|
struct netlib_recvfrom_response_s resp;
|
|
} u;
|
|
|
|
/* Create a NetLink socket with NETLINK_ROUTE protocol */
|
|
|
|
fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
|
|
if (fd < 0)
|
|
{
|
|
int errcode = errno;
|
|
fprintf(stderr, "ERROR: socket() failed: %d\n", errcode);
|
|
return -errcode;
|
|
}
|
|
|
|
/* Bind the socket so that we can use send() and receive() */
|
|
|
|
pid = getpid();
|
|
addr.nl_family = AF_NETLINK;
|
|
addr.nl_pad = 0;
|
|
addr.nl_pid = pid;
|
|
addr.nl_groups = 0;
|
|
|
|
ret = bind(fd, (FAR const struct sockaddr *)&addr,
|
|
sizeof(struct sockaddr_nl));
|
|
if (ret < 0)
|
|
{
|
|
int errcode = errno;
|
|
fprintf(stderr, "ERROR: bind() failed: %d\n", errcode);
|
|
ret = -errcode;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* Initialize the request */
|
|
|
|
thiseq = ++seqno;
|
|
|
|
memset(&req, 0, sizeof(req));
|
|
req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
|
|
req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
|
|
req.hdr.nlmsg_seq = thiseq;
|
|
req.hdr.nlmsg_type = RTM_GETROUTE;
|
|
req.hdr.nlmsg_pid = pid;
|
|
req.gen.rtgen_family = family;
|
|
|
|
nsent = send(fd, &req, req.hdr.nlmsg_len, 0);
|
|
if (nsent < 0)
|
|
{
|
|
int errcode = errno;
|
|
fprintf(stderr, "ERROR: send() failed: %d\n", errcode);
|
|
ret = -errcode;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* Read the response(s) */
|
|
|
|
maxaddr = sizeof(struct sockaddr_storage) - sizeof(sa_family_t);
|
|
|
|
for (enddump = false; !enddump; )
|
|
{
|
|
/* Receive the next device response */
|
|
|
|
nrecvd = recv(fd, &u.rxbuffer, RXBUFFER_SIZE, 0);
|
|
if (nrecvd < 0)
|
|
{
|
|
int errcode = errno;
|
|
fprintf(stderr, "ERROR: recv() failed: %d\n", errcode);
|
|
ret = -errcode;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* Verify the data and transfer the device list to the caller */
|
|
|
|
if (u.resp.hdr.nlmsg_len < sizeof(struct nlmsghdr) ||
|
|
u.resp.hdr.nlmsg_len != nrecvd)
|
|
{
|
|
fprintf(stderr, "ERROR: Bad message\n");
|
|
ret = -EIO;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* The sequence number in the response should match the sequence
|
|
* number in the request (since we created the socket, this should
|
|
* always be true).
|
|
*/
|
|
|
|
if (u.resp.hdr.nlmsg_seq != thiseq)
|
|
{
|
|
fprintf(stderr, "ERROR: Bad sequence number in response\n");
|
|
ret = -EIO;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* This should be a routing table response */
|
|
|
|
if (u.resp.rte.rtm_table != RT_TABLE_MAIN)
|
|
{
|
|
fprintf(stderr, "ERROR: Not a routing table response\n");
|
|
ret = -EIO;
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* Copy the routing table entry to the caller's buffer */
|
|
|
|
switch (u.resp.hdr.nlmsg_type)
|
|
{
|
|
case NLMSG_DONE:
|
|
enddump = true;
|
|
break;
|
|
|
|
case RTM_NEWROUTE:
|
|
{
|
|
FAR struct rtentry *dest;
|
|
FAR struct rtattr *attr;
|
|
unsigned int paylen;
|
|
|
|
/* Verify the expected message length */
|
|
|
|
if (nrecvd <= sizeof(struct netlib_recvfrom_response_s) ||
|
|
u.resp.rte.rtm_family != family)
|
|
{
|
|
fprintf(stderr, "ERROR: Bad massage size: %ld\n",
|
|
(long)nrecvd);
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
/* Decode the response */
|
|
|
|
dest = &rtelist[ncopied];
|
|
memset(dest, 0, sizeof(struct rtentry));
|
|
|
|
attr = &u.resp.attr;
|
|
paylen = u.resp.hdr.nlmsg_len - sizeof(struct nlmsghdr) -
|
|
sizeof(struct rtmsg);
|
|
|
|
for (; RTA_OK(attr, paylen); attr = RTA_NEXT(attr, paylen))
|
|
{
|
|
unsigned int attrlen = RTA_PAYLOAD(attr);
|
|
|
|
switch (attr->rta_type)
|
|
{
|
|
case RTA_DST: /* The destination network */
|
|
ret = copy_address(&dest->rt_dst, RTA_DATA(attr),
|
|
attrlen, maxaddr, family);
|
|
if (ret < 0)
|
|
{
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
break;
|
|
|
|
case RTA_SRC: /* The source address mask */
|
|
break;
|
|
|
|
case RTA_GENMASK: /* The network address mask */
|
|
ret = copy_address(&dest->rt_genmask, RTA_DATA(attr),
|
|
attrlen, maxaddr, family);
|
|
if (ret < 0)
|
|
{
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
break;
|
|
|
|
case RTA_GATEWAY: /* Route packets via this router */
|
|
ret = copy_address(&dest->rt_gateway, RTA_DATA(attr),
|
|
attrlen, maxaddr, family);
|
|
if (ret < 0)
|
|
{
|
|
goto errout_with_socket;
|
|
}
|
|
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
ncopied++;
|
|
}
|
|
break;
|
|
|
|
default:
|
|
fprintf(stderr, "ERROR: Message type %u, length %u\n",
|
|
u.resp.hdr.nlmsg_type, (unsigned)u.resp.hdr.nlmsg_len);
|
|
ret = -EIO;
|
|
goto errout_with_socket;
|
|
}
|
|
}
|
|
|
|
close(fd);
|
|
return ncopied;
|
|
|
|
errout_with_socket:
|
|
close(fd);
|
|
return ret;
|
|
}
|
|
|
|
#endif /* CONFIG_NETLINK_ROUTE && CONFIG_NET_ROUTE */
|