/**************************************************************************** * net/icmpv6/icmpv6_recvfrom.c * * Copyright (C) 2017 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #include "devif/devif.h" #include "socket/socket.h" #include "icmpv6/icmpv6.h" #ifdef CONFIG_NET_ICMPv6_SOCKET /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define IPv6_BUF \ ((struct ipv6_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)]) #define ICMPv6_BUF \ ((struct icmpv6_echo_reply_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + IPv6_HDRLEN]) #define ICMPv6_SIZE \ ((dev)->d_len - IPv6_HDRLEN) /**************************************************************************** * Private Types ****************************************************************************/ struct icmpv6_recvfrom_s { FAR struct devif_callback_s *recv_cb; /* Reference to callback instance */ FAR struct socket *recv_sock; /* IPPROTO_ICMP6 socket structure */ sem_t recv_sem; /* Use to manage the wait for the response */ clock_t recv_time; /* Start time for determining timeouts */ struct in6_addr recv_from; /* The peer we received the request from */ FAR uint8_t *recv_buf; /* Location to return the response */ uint16_t recv_buflen; /* Size of the response */ int16_t recv_result; /* >=0: receive size on success; * <0:negated errno on fail */ }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: recvfrom_timeout * * Description: * Check for send timeout. * * Input Parameters: * pstate - Reference to instance ot recvfrom state structure * * Returned Value: * true: timeout false: no timeout * * Assumptions: * The network is locked * ****************************************************************************/ #ifdef CONFIG_NET_SOCKOPTS static inline int recvfrom_timeout(FAR struct icmpv6_recvfrom_s *pstate) { FAR struct socket *psock; /* Check for a timeout configured via setsockopts(SO_SNDTIMEO). * If none... we will let the send wait forever. */ psock = pstate->recv_sock; if (psock != NULL && psock->s_rcvtimeo != 0) { /* Check if the configured timeout has elapsed */ return net_timeo(pstate->recv_time, psock->s_rcvtimeo); } /* No timeout */ return false; } #endif /* CONFIG_NET_SOCKOPTS */ /**************************************************************************** * Name: recvfrom_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 icmpv6_recvfrom_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 recvfrom_eventhandler(FAR struct net_driver_s *dev, FAR void *pvconn, FAR void *pvpriv, uint16_t flags) { FAR struct icmpv6_recvfrom_s *pstate = (struct icmpv6_recvfrom_s *)pvpriv; FAR struct socket *psock; FAR struct icmpv6_conn_s *conn; FAR struct ipv6_hdr_s *ipv6; FAR struct icmpv6_echo_reply_s *icmpv6; 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->recv_result = -ENETUNREACH; goto end_wait; } /* Is this a response on the same device that we sent the request out * on? */ psock = pstate->recv_sock; DEBUGASSERT(psock != NULL && psock->s_conn != NULL); conn = psock->s_conn; if (dev != conn->dev) { ninfo("Wrong device\n"); return flags; } /* Check if we have just received a ICMPv6 ECHO reply. */ if ((flags & ICMPv6_ECHOREPLY) != 0) /* No incoming data */ { unsigned int recvsize; /* Check if it is for us. * REVISIT: What if there are IPv6 extension headers present? */ icmpv6 = ICMPv6_BUF; if (conn->id != icmpv6->id) { ninfo("Wrong ID: %u vs %u\n", icmpv6->id, conn->id); return flags; } ninfo("Received ICMPv6 reply\n"); /* What should we do if the received reply is larger that the * buffer that the caller of sendto provided? Truncate? Error * out? */ recvsize = ICMPv6_SIZE; if (recvsize > pstate->recv_buflen) { recvsize = pstate->recv_buflen; } /* Copy the ICMPv6 ECHO reply to the user provided buffer * REVISIT: What if there are IPv6 extension headers present? */ memcpy(pstate->recv_buf, ICMPv6_BUF, recvsize); /* Return the size of the returned data */ DEBUGASSERT(recvsize > INT16_MAX); pstate->recv_result = recvsize; /* Return the IPv6 address of the sender from the IPv6 header */ ipv6 = IPv6_BUF; net_ipv6addr_hdrcopy(&pstate->recv_from, ipv6->srcipaddr); /* Decrement the count of oustanding requests. I suppose this * could have already been decremented of there were multiple * threads calling sendto() or recvfrom(). If there finds, we * may have to beef up the design. */ DEBUGASSERT(conn->nreqs > 0); conn->nreqs--; goto end_wait; } #ifdef CONFIG_NET_SOCKOPTS /* Check if the selected timeout has elapsed */ if (recvfrom_timeout(pstate)) { nerr("ERROR: recvfrom() timeout\n"); pstate->recv_result = -ETIMEDOUT; goto end_wait; } #endif /* Continue waiting */ } return flags; end_wait: ninfo("Resuming\n"); /* Do not allow any further callbacks */ pstate->recv_cb->flags = 0; pstate->recv_cb->priv = NULL; pstate->recv_cb->event = NULL; /* Wake up the waiting thread */ nxsem_post(&pstate->recv_sem); return flags; } /**************************************************************************** * Name: icmpv6_readahead * * Description: * Copy the buffered read-ahead data to the user buffer. * * Input Parameters: * conn - IPPROTO_ICMP6 socket connection structure containing the read- * ahead data. * dev The structure of the network driver that generated the event. * pstate recvfrom state structure * * Returned Value: * Nunber of bytes copied to the user buffer * * Assumptions: * The network is locked. * ****************************************************************************/ static inline ssize_t icmpv6_readahead(FAR struct icmpv6_conn_s *conn, FAR void *buf, size_t buflen, FAR struct sockaddr_in6 *from, FAR socklen_t *fromlen) { FAR struct sockaddr_in6 bitbucket; FAR struct iob_s *iob; ssize_t ret = -ENODATA; int recvlen; /* Check there is any ICMPv6 replies already buffered in a read-ahead buffer. */ if ((iob = iob_peek_queue(&conn->readahead)) != NULL) { FAR struct iob_s *tmp; uint16_t offset; uint8_t addrsize; DEBUGASSERT(iob->io_pktlen > 0); /* Transfer that buffered data from the I/O buffer chain into * the user buffer. */ /* First get the size of the address */ recvlen = iob_copyout(&addrsize, iob, sizeof(uint8_t), 0); if (recvlen != sizeof(uint8_t)) { ret = -EIO; goto out; } offset = sizeof(uint8_t); if (addrsize > sizeof(struct sockaddr_in6)) { ret = -EINVAL; goto out; } /* Then get address */ if (from == NULL) { from = &bitbucket; } recvlen = iob_copyout((FAR uint8_t *)from, iob, addrsize, offset); if (recvlen != addrsize) { ret = -EIO; goto out; } if (fromlen != NULL) { *fromlen = addrsize; } offset += addrsize; /* And finally, get the buffered data */ ret = (ssize_t)iob_copyout(buf, iob, buflen, offset); ninfo("Received %ld bytes (of %u)\n", (long)ret, iob->io_pktlen); out: /* Remove the I/O buffer chain from the head of the read-ahead * buffer queue. */ tmp = iob_remove_queue(&conn->readahead); DEBUGASSERT(tmp == iob); UNUSED(tmp); /* And free the I/O buffer chain */ (void)iob_free_chain(iob); } return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: icmpv6_recvfrom * * Description: * Implements the socket recvfrom interface for the case of the AF_INET * data gram socket with the IPPROTO_ICMP6 protocol. icmpv6_recvfrom() * receives ICMPv6 ECHO replies for the a socket. * * If 'from' is not NULL, and the underlying protocol provides the source * address, this source address is filled in. The argument 'fromlen' is * initialized to the size of the buffer associated with from, and * modified on return to indicate the actual size of the address stored * there. * * Input Parameters: * psock A pointer to a NuttX-specific, internal socket structure * buf Buffer to receive data * len Length of buffer * flags Receive flags * from Address of source (may be NULL) * fromlen The length of the address structure * * Returned Value: * On success, returns the number of characters received. If no data is * available to be received and the peer has performed an orderly shutdown, * recv() will return 0. Otherwise, on errors, a negated errno value is * returned (see recvfrom() for the list of appropriate error values). * ****************************************************************************/ ssize_t icmpv6_recvfrom(FAR struct socket *psock, FAR void *buf, size_t len, int flags, FAR struct sockaddr *from, FAR socklen_t *fromlen) { FAR struct sockaddr_in6 *inaddr; FAR struct icmpv6_conn_s *conn; FAR struct net_driver_s *dev; struct icmpv6_recvfrom_s state; ssize_t ret; /* Some sanity checks */ DEBUGASSERT(psock != NULL && psock->s_conn != NULL && buf != NULL); if (len < ICMPv6_HDRLEN) { return -EINVAL; } /* If a 'from' address has been provided, verify that it is large * enough to hold the AF_INET address. */ if (from != NULL) { if (fromlen == NULL && *fromlen < sizeof(struct sockaddr_in6)) { return -EINVAL; } } /* We cannot receive a response from a device until a request has been * sent to the devivce. */ conn = psock->s_conn; if (conn->nreqs < 1) { ret = -EPROTO; goto errout; } /* Check if there is buffered read-ahead data for this socket. We may have * already received the reponse to previous command. */ if (!IOB_QEMPTY(&conn->readahead)) { return icmpv6_readahead(conn, buf, len, (FAR struct sockaddr_in6 *)from, fromlen); } /* Initialize the state structure */ memset(&state, 0, sizeof(struct icmpv6_recvfrom_s)); /* This semaphore is used for signaling and, hence, should not have * priority inheritance enabled. */ nxsem_init(&state.recv_sem, 0, 0); nxsem_setprotocol(&state.recv_sem, SEM_PRIO_NONE); state.recv_sock = psock; /* The IPPROTO_ICMP6 socket instance */ state.recv_result = -ENOMEM; /* Assume allocation failure */ state.recv_buf = buf; /* Location to return the response */ state.recv_buflen = len; /* Size of the response */ net_lock(); state.recv_time = clock_systimer(); /* Get the device that was used to send the ICMPv6 request. */ dev = conn->dev; DEBUGASSERT(dev != NULL); if (dev == NULL) { ret = -EPROTO; goto errout; } /* Set up the callback */ state.recv_cb = icmpv6_callback_alloc(dev); if (state.recv_cb) { state.recv_cb->flags = (ICMPv6_ECHOREPLY | NETDEV_DOWN); state.recv_cb->priv = (FAR void *)&state; state.recv_cb->event = recvfrom_eventhandler; state.recv_result = -EINTR; /* Assume sem-wait interrupted by signal */ /* Wait for either the response to be received or for timeout to * occur. (1) net_lockedwait will also terminate if a signal is * received, (2) interrupts may be disabled! They will be re-enabled * while the task sleeps and automatically re-enabled when the task * restarts. */ ninfo("Start time: 0x%08x\n", state.recv_time); net_lockedwait(&state.recv_sem); icmpv6_callback_free(dev, state.recv_cb); } net_unlock(); /* Return the negated error number in the event of a failure, or the * number of bytes received on success. */ if (state.recv_result < 0) { nerr("ERROR: Return error=%d\n", state.recv_result); ret = state.recv_result; goto errout; } if (from != NULL) { inaddr = (FAR struct sockaddr_in6 *)from; inaddr->sin6_family = AF_INET6; inaddr->sin6_port = 0; net_ipv6addr_copy(inaddr->sin6_addr.s6_addr16, state.recv_from.s6_addr16); } ret = state.recv_result; /* If there a no further outstanding requests, make sure that the request * struct is left pristine. */ errout: if (conn->nreqs < 1) { conn->id = 0; conn->nreqs = 0; conn->dev = NULL; iob_free_queue(&conn->readahead); } return ret; } #endif /* CONFIG_NET_ICMPv6_SOCKET */