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Diffstat (limited to 'nuttx/net/accept.c')
| -rw-r--r-- | nuttx/net/accept.c | 462 |
1 files changed, 462 insertions, 0 deletions
diff --git a/nuttx/net/accept.c b/nuttx/net/accept.c new file mode 100644 index 000000000..07e3f983e --- /dev/null +++ b/nuttx/net/accept.c @@ -0,0 +1,462 @@ +/**************************************************************************** + * net/accept.c + * + * Copyright (C) 2007-2012 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> +#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0 && defined(CONFIG_NET_TCP) + +#include <sys/types.h> +#include <sys/socket.h> + +#include <semaphore.h> +#include <string.h> +#include <errno.h> +#include <assert.h> +#include <debug.h> + +#include <arch/irq.h> + +#include "net_internal.h" + +/**************************************************************************** + * Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +struct accept_s +{ + sem_t acpt_sem; /* Wait for interrupt event */ +#ifdef CONFIG_NET_IPv6 + FAR struct sockaddr_in6 *acpt_addr; /* Return connection adress */ +#else + FAR struct sockaddr_in *acpt_addr; /* Return connection adress */ +#endif + FAR struct uip_conn *acpt_newconn; /* The accepted connection */ + int acpt_result; /* The result of the wait */ +}; + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Function: accept_tcpsender + * + * Description: + * Getting the sender's address from the UDP packet + * + * Parameters: + * conn - The newly accepted TCP connection + * pstate - the recvfrom state structure + * + * Returned Value: + * None + * + * Assumptions: + * Running at the interrupt level + * + ****************************************************************************/ + +#ifdef CONFIG_NET_TCP +#ifdef CONFIG_NET_IPv6 +static inline void accept_tcpsender(FAR struct uip_conn *conn, + FAR struct sockaddr_in6 *addr) +{ + if (addr) + { + addr->sin_family = AF_INET6; + addr->sin_port = conn->rport; + uip_ipaddr_copy(addr->sin6_addr.s6_addr, conn->ripaddr); + } +} +#else +static inline void accept_tcpsender(FAR struct uip_conn *conn, + FAR struct sockaddr_in *addr) +{ + if (addr) + { + addr->sin_family = AF_INET; + addr->sin_port = conn->rport; + uip_ipaddr_copy(addr->sin_addr.s_addr, conn->ripaddr); + } +} +#endif /* CONFIG_NET_IPv6 */ +#endif /* CONFIG_NET_TCP */ + +/**************************************************************************** + * Function: accept_interrupt + * + * Description: + * Receive interrupt level callbacks when connections occur + * + * Parameters: + * listener The conection stucture of the listener + * conn The connection stucture that was just accepted + * + * Returned Value: + * None + * + * Assumptions: + * Running at the interrupt level + * + ****************************************************************************/ + +static int accept_interrupt(struct uip_conn *listener, struct uip_conn *conn) +{ + struct accept_s *pstate = (struct accept_s *)listener->accept_private; + int ret = -EINVAL; + + if (pstate) + { + /* Get the connection address */ + + accept_tcpsender(conn, pstate->acpt_addr); + + /* Save the connection structure */ + + pstate->acpt_newconn = conn; + pstate->acpt_result = OK; + + /* There should be a reference of one on the new connection */ + + DEBUGASSERT(conn->crefs == 1); + + /* Wake-up the waiting caller thread */ + + sem_post(&pstate->acpt_sem); + + /* Stop any further callbacks */ + + listener->accept_private = NULL; + listener->accept = NULL; + ret = OK; + } + + return ret; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Function: accept + * + * Description: + * The accept function is used with connection-based socket types + * (SOCK_STREAM, SOCK_SEQPACKET and SOCK_RDM). It extracts the first + * connection request on the queue of pending connections, creates a new + * connected socket with mostly the same properties as 'sockfd', and + * allocates a new socket descriptor for the socket, which is returned. The + * newly created socket is no longer in the listening state. The original + * socket 'sockfd' is unaffected by this call. Per file descriptor flags + * are not inherited across an accept. + * + * The 'sockfd' argument is a socket descriptor that has been created with + * socket(), bound to a local address with bind(), and is listening for + * connections after a call to listen(). + * + * On return, the 'addr' structure is filled in with the address of the + * connecting entity. The 'addrlen' argument initially contains the size + * of the structure pointed to by 'addr'; on return it will contain the + * actual length of the address returned. + * + * If no pending connections are present on the queue, and the socket is + * not marked as non-blocking, accept blocks the caller until a connection + * is present. If the socket is marked non-blocking and no pending + * connections are present on the queue, accept returns EAGAIN. + * + * Parameters: + * sockfd The listening socket descriptior + * addr Receives the address of the connecting client + * addrlen Input: allocated size of 'addr', Return: returned size of 'addr' + * + * Returned Value: + * Returns -1 on error. If it succeeds, it returns a non-negative integer + * that is a descriptor for the accepted socket. + * + * EAGAIN or EWOULDBLOCK + * The socket is marked non-blocking and no connections are present to + * be accepted. + * EBADF + * The descriptor is invalid. + * ENOTSOCK + * The descriptor references a file, not a socket. + * EOPNOTSUPP + * The referenced socket is not of type SOCK_STREAM. + * EINTR + * The system call was interrupted by a signal that was caught before + * a valid connection arrived. + * ECONNABORTED + * A connection has been aborted. + * EINVAL + * Socket is not listening for connections. + * EMFILE + * The per-process limit of open file descriptors has been reached. + * ENFILE + * The system maximum for file descriptors has been reached. + * EFAULT + * The addr parameter is not in a writable part of the user address + * space. + * ENOBUFS or ENOMEM + * Not enough free memory. + * EPROTO + * Protocol error. + * EPERM + * Firewall rules forbid connection. + * + * Assumptions: + * + ****************************************************************************/ + +int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen) +{ + FAR struct socket *psock = sockfd_socket(sockfd); + FAR struct socket *pnewsock; + FAR struct uip_conn *conn; + struct accept_s state; +#ifdef CONFIG_NET_IPv6 + FAR struct sockaddr_in6 *inaddr = (struct sockaddr_in6 *)addr; +#else + FAR struct sockaddr_in *inaddr = (struct sockaddr_in *)addr; +#endif + uip_lock_t save; + int newfd; + int err; + int ret; + + /* Verify that the sockfd corresponds to valid, allocated socket */ + + if (!psock || psock->s_crefs <= 0) + { + /* It is not a valid socket description. Distinguish between the cases + * where sockfd is a just valid and when it is a valid file descriptor used + * in the wrong context. + */ + +#if CONFIG_NFILE_DESCRIPTORS > 0 + if ((unsigned int)sockfd < CONFIG_NFILE_DESCRIPTORS) + { + err = ENOTSOCK; + } + else +#endif + { + err = EBADF; + } + goto errout; + } + + /* We have a socket descriptor, but it is a stream? */ + + if (psock->s_type != SOCK_STREAM) + { + err = EOPNOTSUPP; + goto errout; + } + + /* Is the socket listening for a connection? */ + + if (!_SS_ISLISTENING(psock->s_flags)) + { + err = EINVAL; + goto errout; + } + + /* Verify that a valid memory block has been provided to receive the + * address + */ + + if (addr) + { +#ifdef CONFIG_NET_IPv6 + if (*addrlen < sizeof(struct sockaddr_in6)) +#else + if (*addrlen < sizeof(struct sockaddr_in)) +#endif + { + err = EBADF; + goto errout; + } + } + + /* Allocate a socket descriptor for the new connection now (so that it + * cannot fail later) + */ + + newfd = sockfd_allocate(0); + if (newfd < 0) + { + err = ENFILE; + goto errout; + } + + pnewsock = sockfd_socket(newfd); + if (!pnewsock) + { + err = ENFILE; + goto errout_with_socket; + } + + /* Check the backlog to see if there is a connection already pending for + * this listener. + */ + + save = uip_lock(); + conn = (struct uip_conn *)psock->s_conn; + +#ifdef CONFIG_NET_TCPBACKLOG + state.acpt_newconn = uip_backlogremove(conn); + if (state.acpt_newconn) + { + /* Yes... get the address of the connected client */ + + nvdbg("Pending conn=%p\n", state.acpt_newconn); + accept_tcpsender(state.acpt_newconn, inaddr); + } + + /* In general, this uIP-based implementation will not support non-blocking + * socket operations... except in a few cases: Here for TCP accept with backlog + * enabled. If this socket is configured as non-blocking then return EAGAIN + * if there is no pending connection in the backlog. + */ + + else if (_SS_ISNONBLOCK(psock->s_flags)) + { + err = EAGAIN; + goto errout_with_lock; + } + else +#endif + { + /* Set the socket state to accepting */ + + psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_ACCEPT); + + /* Perform the TCP accept operation */ + + /* Initialize the state structure. This is done with interrupts + * disabled because we don't want anything to happen until we + * are ready. + */ + + state.acpt_addr = inaddr; + state.acpt_newconn = NULL; + state.acpt_result = OK; + sem_init(&state.acpt_sem, 0, 0); + + /* Set up the callback in the connection */ + + conn->accept_private = (void*)&state; + conn->accept = accept_interrupt; + + /* Wait for the send to complete or an error to occur: NOTES: (1) + * uip_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. + */ + + ret = uip_lockedwait(&state.acpt_sem); + + /* Make sure that no further interrupts are processed */ + + conn->accept_private = NULL; + conn->accept = NULL; + + sem_destroy(&state. acpt_sem); + + /* Set the socket state to idle */ + + psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE); + + /* Check for a errors. Errors are signaled by negative errno values + * for the send length. + */ + + if (state.acpt_result != 0) + { + err = state.acpt_result; + goto errout_with_lock; + } + + /* If uip_lockedwait failed, then we were probably reawakened by a signal. In + * this case, uip_lockedwait will have set errno appropriately. + */ + + if (ret < 0) + { + err = -ret; + goto errout_with_lock; + } + } + + /* Initialize the socket structure and mark the socket as connected. + * (The reference count on the new connection structure was set in the + * interrupt handler). + */ + + pnewsock->s_type = SOCK_STREAM; + pnewsock->s_conn = state.acpt_newconn; + pnewsock->s_flags |= _SF_CONNECTED; + pnewsock->s_flags &= ~_SF_CLOSED; + + /* Begin monitoring for TCP connection events on the newly connected socket */ + + net_startmonitor(pnewsock); + uip_unlock(save); + return newfd; + +errout_with_lock: + uip_unlock(save); + +errout_with_socket: + sockfd_release(newfd); + +errout: + errno = err; + return ERROR; +} + +#endif /* CONFIG_NET && CONFIG_NSOCKET_DESCRIPTORS && CONFIG_NET_TCP */ |