/****************************************************************************
* net/icmp/icmp_sendmsg.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <assert.h>
#include <debug.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <nuttx/semaphore.h>
#include <nuttx/mm/iob.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/netstats.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/icmp.h>
#include "utils/utils.h"
#include "socket/socket.h"
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "inet/inet.h"
#include "arp/arp.h"
#include "icmp/icmp.h"
#ifdef CONFIG_NET_ICMP_SOCKET
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define IPv4BUF \
((FAR struct ipv4_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)])
#define ICMPBUF \
((FAR struct icmp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv4_HDRLEN])
/****************************************************************************
* Private Types
****************************************************************************/
struct icmp_sendto_s
{
FAR struct devif_callback_s *snd_cb; /* Reference to callback instance */
sem_t snd_sem; /* Use to manage the wait for send
* complete */
in_addr_t snd_toaddr; /* The peer to send the request to */
FAR const uint8_t *snd_buf; /* ICMP header + data payload */
uint16_t snd_buflen; /* Size of the ICMP header + data
* payload */
int16_t snd_result; /* 0: success; <0:negated errno on
* fail */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sendto_request
*
* Description:
* Setup to send an ICMP request packet
*
* Input Parameters:
* dev - The device driver structure to use in the send operation
* pstate - Reference to an instance of the ICMP sendto state structure
*
* Returned Value:
* None
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
static void sendto_request(FAR struct net_driver_s *dev,
FAR struct icmp_sendto_s *pstate)
{
FAR struct ipv4_hdr_s *ipv4;
FAR struct icmp_hdr_s *icmp;
IFF_SET_IPv4(dev->d_flags);
/* The total length to send is the size of the application data plus the
* IP and ICMP headers (and, eventually, the Ethernet header)
*/
dev->d_len = IPv4_HDRLEN + pstate->snd_buflen;
/* The total size of the data (including the size of the ICMP header) */
dev->d_sndlen += pstate->snd_buflen;
/* Initialize the IP header. */
ipv4 = IPv4BUF;
ipv4->vhl = 0x45;
ipv4->tos = 0;
ipv4->len[0] = (dev->d_len >> 8);
ipv4->len[1] = (dev->d_len & 0xff);
++g_ipid;
ipv4->ipid[0] = g_ipid >> 8;
ipv4->ipid[1] = g_ipid & 0xff;
ipv4->ipoffset[0] = IP_FLAG_DONTFRAG >> 8;
ipv4->ipoffset[1] = IP_FLAG_DONTFRAG & 0xff;
ipv4->ttl = IP_TTL_DEFAULT;
ipv4->proto = IP_PROTO_ICMP;
net_ipv4addr_hdrcopy(ipv4->srcipaddr, &dev->d_ipaddr);
net_ipv4addr_hdrcopy(ipv4->destipaddr, &pstate->snd_toaddr);
/* Copy the ICMP header and payload into place after the IPv4 header */
icmp = ICMPBUF;
memcpy(icmp, pstate->snd_buf, pstate->snd_buflen);
/* Calculate IP checksum. */
ipv4->ipchksum = 0;
ipv4->ipchksum = ~(ipv4_chksum(dev));
/* Calculate the ICMP checksum. */
icmp->icmpchksum = 0;
icmp->icmpchksum = ~(icmp_chksum(dev, pstate->snd_buflen));
if (icmp->icmpchksum == 0)
{
icmp->icmpchksum = 0xffff;
}
ninfo("Outgoing ICMP packet length: %d (%d)\n",
dev->d_len, (ipv4->len[0] << 8) | ipv4->len[1]);
#ifdef CONFIG_NET_STATISTICS
g_netstats.icmp.sent++;
g_netstats.ipv4.sent++;
#endif
}
/****************************************************************************
* Name: sendto_eventhandler
*
* Description:
* This function is called with the network locked to perform the actual
* ECHO request and/or ECHO reply actions when polled by the lower, device
* interfacing layer.
*
* Input Parameters:
* dev The structure of the network driver that generated the
* event.
* conn The received packet, cast to (void *)
* pvpriv An instance of struct icmp_sendto_s cast to (void *)
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* Modified value of the input flags
*
* Assumptions:
* The network is locked.
*
****************************************************************************/
static uint16_t sendto_eventhandler(FAR struct net_driver_s *dev,
FAR void *conn,
FAR void *pvpriv, uint16_t flags)
{
FAR struct icmp_sendto_s *pstate = (struct icmp_sendto_s *)pvpriv;
ninfo("flags: %04x\n", flags);
if (pstate != NULL)
{
/* Check if the network is still up */
if ((flags & NETDEV_DOWN) != 0)
{
nerr("ERROR: Interface is down\n");
pstate->snd_result = -ENETUNREACH;
goto end_wait;
}
/* Check:
* If the outgoing packet is available (it may have been claimed
* by a sendto event handler serving a different thread)
* -OR-
* If the output buffer currently contains unprocessed incoming
* data.
* -OR-
* If we have already sent the ECHO request
*
* In the first two cases, we will just have to wait for the next
* polling cycle.
*/
if (dev->d_sndlen <= 0 && /* Packet available */
(flags & ICMP_NEWDATA) == 0) /* No incoming data */
{
/* Send the ICMP echo request. */
ninfo("Send ICMP request\n");
sendto_request(dev, pstate);
pstate->snd_result = OK;
goto end_wait;
}
/* Continue waiting */
}
return flags;
end_wait:
ninfo("Resuming\n");
/* Do not allow any further callbacks */
pstate->snd_cb->flags = 0;
pstate->snd_cb->priv = NULL;
pstate->snd_cb->event = NULL;
/* Wake up the waiting thread */
nxsem_post(&pstate->snd_sem);
return flags;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: icmp_sendmsg
*
* Description:
* Implements the sendmsg() operation for the case of the IPPROTO_ICMP
* socket. The 'buf' parameter points to a block of memory that includes
* an ICMP request header, followed by any payload that accompanies the
* request. The 'len' parameter includes both the size of the ICMP header
* and the following payload.
*
* Input Parameters:
* psock A pointer to a NuttX-specific, internal socket structure
* msg Message to send
* flags Send flags
*
* Returned Value:
* On success, returns the number of characters sent. On error, a negated
* errno value is returned (see sendmsg() for the list of appropriate error
* values.
*
****************************************************************************/
ssize_t icmp_sendmsg(FAR struct socket *psock, FAR struct msghdr *msg,
int flags)
{
FAR const void *buf = msg->msg_iov->iov_base;
size_t len = msg->msg_iov->iov_len;
FAR const struct sockaddr *to = msg->msg_name;
socklen_t tolen = msg->msg_namelen;
FAR const struct sockaddr_in *inaddr;
FAR struct net_driver_s *dev;
FAR struct icmp_conn_s *conn;
FAR struct icmp_hdr_s *icmp;
struct icmp_sendto_s state;
ssize_t ret;
/* Validity check, only single iov supported */
if (msg->msg_iovlen != 1)
{
return -ENOTSUP;
}
if (to == NULL)
{
/* icmp_send() */
/* ICMP sockets cannot be bound and, hence, cannot support any
* connection-oriented data transfer.
*/
return -EDESTADDRREQ;
}
/* Some sanity checks */
DEBUGASSERT(psock != NULL && psock->s_conn != NULL &&
buf != NULL && to != NULL);
if (len < ICMP_HDRLEN || tolen < sizeof(struct sockaddr_in))
{
return -EINVAL;
}
conn = psock->s_conn;
inaddr = (FAR const struct sockaddr_in *)to;
/* Get the device that will be used to route this ICMP ECHO request */
dev = netdev_findby_ripv4addr(INADDR_ANY, inaddr->sin_addr.s_addr);
if (dev == NULL)
{
nerr("ERROR: Not reachable\n");
ret = -ENETUNREACH;
goto errout;
}
/* Sanity check if the request len is greater than the net payload len */
if (len > NETDEV_PKTSIZE(dev) - (NET_LL_HDRLEN(dev) + IPv4_HDRLEN))
{
nerr("ERROR: Invalid packet length\n");
return -EINVAL;
}
/* If we are no longer processing the same ping ID, then flush any pending
* packets from the read-ahead buffer.
*
* REVISIT: How to we free up any lingering responses if there are no
* further pings?
*/
icmp = (FAR struct icmp_hdr_s *)buf;
if (icmp->type != ICMP_ECHO_REQUEST || icmp->id != conn->id ||
dev != conn->dev)
{
conn->id = 0;
conn->nreqs = 0;
conn->dev = NULL;
iob_free_queue(&conn->readahead, IOBUSER_NET_SOCK_ICMP);
}
#ifdef CONFIG_NET_ARP_SEND
/* Make sure that the IP address mapping is in the ARP table */
ret = arp_send(inaddr->sin_addr.s_addr);
if (ret < 0)
{
nerr("ERROR: Not reachable\n");
ret = -ENETUNREACH;
goto errout;
}
#endif
/* Initialize the state structure */
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
nxsem_init(&state.snd_sem, 0, 0);
nxsem_set_protocol(&state.snd_sem, SEM_PRIO_NONE);
state.snd_result = -ENOMEM; /* Assume allocation failure */
state.snd_toaddr = inaddr->sin_addr.s_addr; /* Address of the peer to send
* the request */
state.snd_buf = buf; /* ICMP header + data payload */
state.snd_buflen = len; /* Size of the ICMP header +
* data payload */
net_lock();
/* Set up the callback */
state.snd_cb = icmp_callback_alloc(dev, conn);
if (state.snd_cb != NULL)
{
state.snd_cb->flags = (ICMP_POLL | NETDEV_DOWN);
state.snd_cb->priv = (FAR void *)&state;
state.snd_cb->event = sendto_eventhandler;
/* Setup to receive ICMP ECHO replies */
if (icmp->type == ICMP_ECHO_REQUEST)
{
conn->id = icmp->id;
conn->nreqs = 1;
}
conn->dev = dev;
/* Notify the device driver of the availability of TX data */
netdev_txnotify_dev(dev);
/* Wait for either the send to complete or for timeout to occur.
* net_timedwait will also terminate if a signal is received.
*/
ret = net_timedwait(&state.snd_sem,
_SO_TIMEOUT(conn->sconn.s_sndtimeo));
if (ret < 0)
{
if (ret == -ETIMEDOUT)
{
/* Check if this device is on the same network as the
* destination device.
*/
if (!net_ipv4addr_maskcmp(state.snd_toaddr, dev->d_ipaddr,
dev->d_netmask))
{
/* Destination address was not on the local network served
* by this device. If a timeout occurs, then the most
* likely reason is that the destination address is not
* reachable.
*/
ret = -ENETUNREACH;
}
else
{
ret = -EAGAIN;
}
}
state.snd_result = ret;
}
icmp_callback_free(dev, conn, state.snd_cb);
}
net_unlock();
/* Return the negated error number in the event of a failure, or the
* number of bytes sent on success.
*/
if (state.snd_result < 0)
{
nerr("ERROR: Return error=%d\n", state.snd_result);
ret = state.snd_result;
goto errout;
}
return len;
errout:
conn->id = 0;
conn->nreqs = 0;
conn->dev = NULL;
iob_free_queue(&conn->readahead, IOBUSER_NET_SOCK_ICMP);
return ret;
}
#endif /* CONFIG_NET_ICMP_SOCKET */