netutils/netlib/netlib_getarptab.c: Add a function to read the entire ARP tableusing NETLINK_ROUTE protocol.

This commit is contained in:
Gregory Nutt 2019-11-03 15:13:47 -06:00
parent 29160741d8
commit 768218ee81
3 changed files with 193 additions and 0 deletions

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@ -312,6 +312,10 @@ int netlib_get_arpmapping(FAR const struct sockaddr_in *inaddr,
FAR uint8_t *macaddr);
int netlib_set_arpmapping(FAR const struct sockaddr_in *inaddr,
FAR const uint8_t *macaddr);
#ifdef CONFIG_NETLINK_ROUTE
struct arp_enty_s;
int netlib_get_arptable(FAR struct arp_enty_s *arptab, unsigned int nentries);
#endif
#endif
#ifdef HAVE_ROUTE_PROCFS

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@ -84,6 +84,14 @@ CSRCS += netlib_server.c netlib_listenon.c
endif
endif
# These require Netlink support
ifeq ($(CONFIG_NETLINK_ROUTE),y)
ifeq ($(CONFIG_NET_ARP),y)
CSRCS += netlib_getarptab.c
endif
endif
# These require wireless IOCTL support */
ifeq ($(CONFIG_NETDEV_WIRELESS_IOCTL),y)

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@ -0,0 +1,181 @@
/****************************************************************************
* netutils/netlib/netlib_getarptab.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 <stdlib.h>
#include <string.h>
#include <errno.h>
#include <errno.h>
#include <netpacket/netlink.h>
#include <nuttx/net/arp.h>
#include "netutils/netlib.h"
#if defined(CONFIG_NET_ARP) && defined(CONFIG_NETLINK_ROUTE)
/****************************************************************************
* Private Types
****************************************************************************/
struct netlib_sendto_request_s
{
struct nlmsghdr hdr;
struct ndmsg msg;
};
struct netlib_recvfrom_response_s
{
struct nlmsghdr hdr;
struct ndmsg msg;
struct rtattr attr;
uint8_t data[1];
};
#define SIZEOF_NETLIB_RECVFROM_RESPONSE_S(n) \
(sizeof(struct netlib_recvfrom_response_s) + (n) - 1)
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: netlib_get_arptable
*
* Description:
* Attempt to read the entire ARP table into a buffer.
*
* Parameters:
* arptab - The location to store the copy of the ARP table
* nentries - The size of the provided arptab in number of entries of
* size sizeof(struct arp_entry_s)
*
* Return:
* 0 on success; a negated errno value on failure.
*
****************************************************************************/
int netlib_get_arptable(FAR struct arp_enty_s *arptab, unsigned int nentries)
{
FAR struct netlib_recvfrom_response_s *resp;
struct netlib_sendto_request_s req;
unsigned int allocsize;
ssize_t nsent;
ssize_t nrecvd;
ssize_t paysize;
ssize_t maxsize;
int fd;
int ret = EXIT_FAILURE;
/* Allocate a buffer to hold the response */
maxsize = CONFIG_NET_ARPTAB_SIZE * sizeof(struct arp_entry_s);
allocsize = SIZEOF_NETLIB_RECVFROM_RESPONSE_S(maxsize);
resp = (FAR struct netlib_recvfrom_response_s *)malloc(allocsize);
if (resp == NULL)
{
fprintf(stderr, "ERROR: Faile to allocat response buffer\n");
return EXIT_FAILURE;
}
/* 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);
goto errout_with_resp;
}
/* Initialize the request */
memset(&req, 0, sizeof(req));
req.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg));
req.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT | NLM_F_REQUEST;
req.hdr.nlmsg_type = RTM_GETNEIGH;
req.msg.ndm_family = AF_INET;
nsent = send(fd, &req, req.hdr.nlmsg_len, 0);
if (nsent < 0)
{
int errcode = errno;
fprintf(stderr, "ERROR: send() failed: %d\n", errcode);
goto errout_with_socket;
}
nrecvd = recv(fd, resp, allocsize, 0);
if (nrecvd < 0)
{
int errcode = errno;
fprintf(stderr, "ERROR: recv() failed: %d\n", errcode);
goto errout_with_socket;
}
/* Verify the data and transfer the ARP table data to the caller */
if (resp->hdr.nlmsg_len < sizeof(struct nlmsghdr) ||
resp->hdr.nlmsg_len > nrecvd)
{
fprintf(stderr, "ERROR: Bad message\n");
goto errout_with_socket;
}
/* Copy the ARP table data to the caller's buffer */
paysize = resp->attr.rta_len;
if (paysize > maxsize)
{
paysize = maxsize;
}
memcpy(arptab, resp->data, paysize);
ret = EXIT_SUCCESS;
errout_with_socket:
close(fd);
errout_with_resp:
free(resp);
return ret;
}
#endif /* CONFIG_NET_ARP && CONFIG_NETLINK_ROUTE */