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Diffstat (limited to 'net/ipv4/af_inet.c')
-rw-r--r--net/ipv4/af_inet.c1188
1 files changed, 1188 insertions, 0 deletions
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
new file mode 100644
index 000000000000..c34dab67e461
--- /dev/null
+++ b/net/ipv4/af_inet.c
@@ -0,0 +1,1188 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * PF_INET protocol family socket handler.
+ *
+ * Version: $Id: af_inet.c,v 1.137 2002/02/01 22:01:03 davem Exp $
+ *
+ * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Florian La Roche, <flla@stud.uni-sb.de>
+ * Alan Cox, <A.Cox@swansea.ac.uk>
+ *
+ * Changes (see also sock.c)
+ *
+ * piggy,
+ * Karl Knutson : Socket protocol table
+ * A.N.Kuznetsov : Socket death error in accept().
+ * John Richardson : Fix non blocking error in connect()
+ * so sockets that fail to connect
+ * don't return -EINPROGRESS.
+ * Alan Cox : Asynchronous I/O support
+ * Alan Cox : Keep correct socket pointer on sock
+ * structures
+ * when accept() ed
+ * Alan Cox : Semantics of SO_LINGER aren't state
+ * moved to close when you look carefully.
+ * With this fixed and the accept bug fixed
+ * some RPC stuff seems happier.
+ * Niibe Yutaka : 4.4BSD style write async I/O
+ * Alan Cox,
+ * Tony Gale : Fixed reuse semantics.
+ * Alan Cox : bind() shouldn't abort existing but dead
+ * sockets. Stops FTP netin:.. I hope.
+ * Alan Cox : bind() works correctly for RAW sockets.
+ * Note that FreeBSD at least was broken
+ * in this respect so be careful with
+ * compatibility tests...
+ * Alan Cox : routing cache support
+ * Alan Cox : memzero the socket structure for
+ * compactness.
+ * Matt Day : nonblock connect error handler
+ * Alan Cox : Allow large numbers of pending sockets
+ * (eg for big web sites), but only if
+ * specifically application requested.
+ * Alan Cox : New buffering throughout IP. Used
+ * dumbly.
+ * Alan Cox : New buffering now used smartly.
+ * Alan Cox : BSD rather than common sense
+ * interpretation of listen.
+ * Germano Caronni : Assorted small races.
+ * Alan Cox : sendmsg/recvmsg basic support.
+ * Alan Cox : Only sendmsg/recvmsg now supported.
+ * Alan Cox : Locked down bind (see security list).
+ * Alan Cox : Loosened bind a little.
+ * Mike McLagan : ADD/DEL DLCI Ioctls
+ * Willy Konynenberg : Transparent proxying support.
+ * David S. Miller : New socket lookup architecture.
+ * Some other random speedups.
+ * Cyrus Durgin : Cleaned up file for kmod hacks.
+ * Andi Kleen : Fix inet_stream_connect TCP race.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/netfilter_ipv4.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <linux/smp_lock.h>
+#include <linux/inet.h>
+#include <linux/igmp.h>
+#include <linux/netdevice.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/arp.h>
+#include <net/route.h>
+#include <net/ip_fib.h>
+#include <net/tcp.h>
+#include <net/udp.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/raw.h>
+#include <net/icmp.h>
+#include <net/ipip.h>
+#include <net/inet_common.h>
+#include <net/xfrm.h>
+#ifdef CONFIG_IP_MROUTE
+#include <linux/mroute.h>
+#endif
+
+DEFINE_SNMP_STAT(struct linux_mib, net_statistics);
+
+#ifdef INET_REFCNT_DEBUG
+atomic_t inet_sock_nr;
+#endif
+
+extern void ip_mc_drop_socket(struct sock *sk);
+
+/* The inetsw table contains everything that inet_create needs to
+ * build a new socket.
+ */
+static struct list_head inetsw[SOCK_MAX];
+static DEFINE_SPINLOCK(inetsw_lock);
+
+/* New destruction routine */
+
+void inet_sock_destruct(struct sock *sk)
+{
+ struct inet_sock *inet = inet_sk(sk);
+
+ __skb_queue_purge(&sk->sk_receive_queue);
+ __skb_queue_purge(&sk->sk_error_queue);
+
+ if (sk->sk_type == SOCK_STREAM && sk->sk_state != TCP_CLOSE) {
+ printk("Attempt to release TCP socket in state %d %p\n",
+ sk->sk_state, sk);
+ return;
+ }
+ if (!sock_flag(sk, SOCK_DEAD)) {
+ printk("Attempt to release alive inet socket %p\n", sk);
+ return;
+ }
+
+ BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
+ BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
+ BUG_TRAP(!sk->sk_wmem_queued);
+ BUG_TRAP(!sk->sk_forward_alloc);
+
+ if (inet->opt)
+ kfree(inet->opt);
+ dst_release(sk->sk_dst_cache);
+#ifdef INET_REFCNT_DEBUG
+ atomic_dec(&inet_sock_nr);
+ printk(KERN_DEBUG "INET socket %p released, %d are still alive\n",
+ sk, atomic_read(&inet_sock_nr));
+#endif
+}
+
+/*
+ * The routines beyond this point handle the behaviour of an AF_INET
+ * socket object. Mostly it punts to the subprotocols of IP to do
+ * the work.
+ */
+
+/*
+ * Automatically bind an unbound socket.
+ */
+
+static int inet_autobind(struct sock *sk)
+{
+ struct inet_sock *inet;
+ /* We may need to bind the socket. */
+ lock_sock(sk);
+ inet = inet_sk(sk);
+ if (!inet->num) {
+ if (sk->sk_prot->get_port(sk, 0)) {
+ release_sock(sk);
+ return -EAGAIN;
+ }
+ inet->sport = htons(inet->num);
+ }
+ release_sock(sk);
+ return 0;
+}
+
+/*
+ * Move a socket into listening state.
+ */
+int inet_listen(struct socket *sock, int backlog)
+{
+ struct sock *sk = sock->sk;
+ unsigned char old_state;
+ int err;
+
+ lock_sock(sk);
+
+ err = -EINVAL;
+ if (sock->state != SS_UNCONNECTED || sock->type != SOCK_STREAM)
+ goto out;
+
+ old_state = sk->sk_state;
+ if (!((1 << old_state) & (TCPF_CLOSE | TCPF_LISTEN)))
+ goto out;
+
+ /* Really, if the socket is already in listen state
+ * we can only allow the backlog to be adjusted.
+ */
+ if (old_state != TCP_LISTEN) {
+ err = tcp_listen_start(sk);
+ if (err)
+ goto out;
+ }
+ sk->sk_max_ack_backlog = backlog;
+ err = 0;
+
+out:
+ release_sock(sk);
+ return err;
+}
+
+/*
+ * Create an inet socket.
+ */
+
+static int inet_create(struct socket *sock, int protocol)
+{
+ struct sock *sk;
+ struct list_head *p;
+ struct inet_protosw *answer;
+ struct inet_sock *inet;
+ struct proto *answer_prot;
+ unsigned char answer_flags;
+ char answer_no_check;
+ int err;
+
+ sock->state = SS_UNCONNECTED;
+
+ /* Look for the requested type/protocol pair. */
+ answer = NULL;
+ rcu_read_lock();
+ list_for_each_rcu(p, &inetsw[sock->type]) {
+ answer = list_entry(p, struct inet_protosw, list);
+
+ /* Check the non-wild match. */
+ if (protocol == answer->protocol) {
+ if (protocol != IPPROTO_IP)
+ break;
+ } else {
+ /* Check for the two wild cases. */
+ if (IPPROTO_IP == protocol) {
+ protocol = answer->protocol;
+ break;
+ }
+ if (IPPROTO_IP == answer->protocol)
+ break;
+ }
+ answer = NULL;
+ }
+
+ err = -ESOCKTNOSUPPORT;
+ if (!answer)
+ goto out_rcu_unlock;
+ err = -EPERM;
+ if (answer->capability > 0 && !capable(answer->capability))
+ goto out_rcu_unlock;
+ err = -EPROTONOSUPPORT;
+ if (!protocol)
+ goto out_rcu_unlock;
+
+ sock->ops = answer->ops;
+ answer_prot = answer->prot;
+ answer_no_check = answer->no_check;
+ answer_flags = answer->flags;
+ rcu_read_unlock();
+
+ BUG_TRAP(answer_prot->slab != NULL);
+
+ err = -ENOBUFS;
+ sk = sk_alloc(PF_INET, GFP_KERNEL, answer_prot, 1);
+ if (sk == NULL)
+ goto out;
+
+ err = 0;
+ sk->sk_no_check = answer_no_check;
+ if (INET_PROTOSW_REUSE & answer_flags)
+ sk->sk_reuse = 1;
+
+ inet = inet_sk(sk);
+
+ if (SOCK_RAW == sock->type) {
+ inet->num = protocol;
+ if (IPPROTO_RAW == protocol)
+ inet->hdrincl = 1;
+ }
+
+ if (ipv4_config.no_pmtu_disc)
+ inet->pmtudisc = IP_PMTUDISC_DONT;
+ else
+ inet->pmtudisc = IP_PMTUDISC_WANT;
+
+ inet->id = 0;
+
+ sock_init_data(sock, sk);
+
+ sk->sk_destruct = inet_sock_destruct;
+ sk->sk_family = PF_INET;
+ sk->sk_protocol = protocol;
+ sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
+
+ inet->uc_ttl = -1;
+ inet->mc_loop = 1;
+ inet->mc_ttl = 1;
+ inet->mc_index = 0;
+ inet->mc_list = NULL;
+
+#ifdef INET_REFCNT_DEBUG
+ atomic_inc(&inet_sock_nr);
+#endif
+
+ if (inet->num) {
+ /* It assumes that any protocol which allows
+ * the user to assign a number at socket
+ * creation time automatically
+ * shares.
+ */
+ inet->sport = htons(inet->num);
+ /* Add to protocol hash chains. */
+ sk->sk_prot->hash(sk);
+ }
+
+ if (sk->sk_prot->init) {
+ err = sk->sk_prot->init(sk);
+ if (err)
+ sk_common_release(sk);
+ }
+out:
+ return err;
+out_rcu_unlock:
+ rcu_read_unlock();
+ goto out;
+}
+
+
+/*
+ * The peer socket should always be NULL (or else). When we call this
+ * function we are destroying the object and from then on nobody
+ * should refer to it.
+ */
+int inet_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+
+ if (sk) {
+ long timeout;
+
+ /* Applications forget to leave groups before exiting */
+ ip_mc_drop_socket(sk);
+
+ /* If linger is set, we don't return until the close
+ * is complete. Otherwise we return immediately. The
+ * actually closing is done the same either way.
+ *
+ * If the close is due to the process exiting, we never
+ * linger..
+ */
+ timeout = 0;
+ if (sock_flag(sk, SOCK_LINGER) &&
+ !(current->flags & PF_EXITING))
+ timeout = sk->sk_lingertime;
+ sock->sk = NULL;
+ sk->sk_prot->close(sk, timeout);
+ }
+ return 0;
+}
+
+/* It is off by default, see below. */
+int sysctl_ip_nonlocal_bind;
+
+int inet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+ struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
+ struct sock *sk = sock->sk;
+ struct inet_sock *inet = inet_sk(sk);
+ unsigned short snum;
+ int chk_addr_ret;
+ int err;
+
+ /* If the socket has its own bind function then use it. (RAW) */
+ if (sk->sk_prot->bind) {
+ err = sk->sk_prot->bind(sk, uaddr, addr_len);
+ goto out;
+ }
+ err = -EINVAL;
+ if (addr_len < sizeof(struct sockaddr_in))
+ goto out;
+
+ chk_addr_ret = inet_addr_type(addr->sin_addr.s_addr);
+
+ /* Not specified by any standard per-se, however it breaks too
+ * many applications when removed. It is unfortunate since
+ * allowing applications to make a non-local bind solves
+ * several problems with systems using dynamic addressing.
+ * (ie. your servers still start up even if your ISDN link
+ * is temporarily down)
+ */
+ err = -EADDRNOTAVAIL;
+ if (!sysctl_ip_nonlocal_bind &&
+ !inet->freebind &&
+ addr->sin_addr.s_addr != INADDR_ANY &&
+ chk_addr_ret != RTN_LOCAL &&
+ chk_addr_ret != RTN_MULTICAST &&
+ chk_addr_ret != RTN_BROADCAST)
+ goto out;
+
+ snum = ntohs(addr->sin_port);
+ err = -EACCES;
+ if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+ goto out;
+
+ /* We keep a pair of addresses. rcv_saddr is the one
+ * used by hash lookups, and saddr is used for transmit.
+ *
+ * In the BSD API these are the same except where it
+ * would be illegal to use them (multicast/broadcast) in
+ * which case the sending device address is used.
+ */
+ lock_sock(sk);
+
+ /* Check these errors (active socket, double bind). */
+ err = -EINVAL;
+ if (sk->sk_state != TCP_CLOSE || inet->num)
+ goto out_release_sock;
+
+ inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr;
+ if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
+ inet->saddr = 0; /* Use device */
+
+ /* Make sure we are allowed to bind here. */
+ if (sk->sk_prot->get_port(sk, snum)) {
+ inet->saddr = inet->rcv_saddr = 0;
+ err = -EADDRINUSE;
+ goto out_release_sock;
+ }
+
+ if (inet->rcv_saddr)
+ sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
+ if (snum)
+ sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
+ inet->sport = htons(inet->num);
+ inet->daddr = 0;
+ inet->dport = 0;
+ sk_dst_reset(sk);
+ err = 0;
+out_release_sock:
+ release_sock(sk);
+out:
+ return err;
+}
+
+int inet_dgram_connect(struct socket *sock, struct sockaddr * uaddr,
+ int addr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+
+ if (uaddr->sa_family == AF_UNSPEC)
+ return sk->sk_prot->disconnect(sk, flags);
+
+ if (!inet_sk(sk)->num && inet_autobind(sk))
+ return -EAGAIN;
+ return sk->sk_prot->connect(sk, (struct sockaddr *)uaddr, addr_len);
+}
+
+static long inet_wait_for_connect(struct sock *sk, long timeo)
+{
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+
+ /* Basic assumption: if someone sets sk->sk_err, he _must_
+ * change state of the socket from TCP_SYN_*.
+ * Connect() does not allow to get error notifications
+ * without closing the socket.
+ */
+ while ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
+ release_sock(sk);
+ timeo = schedule_timeout(timeo);
+ lock_sock(sk);
+ if (signal_pending(current) || !timeo)
+ break;
+ prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
+ }
+ finish_wait(sk->sk_sleep, &wait);
+ return timeo;
+}
+
+/*
+ * Connect to a remote host. There is regrettably still a little
+ * TCP 'magic' in here.
+ */
+int inet_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ int err;
+ long timeo;
+
+ lock_sock(sk);
+
+ if (uaddr->sa_family == AF_UNSPEC) {
+ err = sk->sk_prot->disconnect(sk, flags);
+ sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
+ goto out;
+ }
+
+ switch (sock->state) {
+ default:
+ err = -EINVAL;
+ goto out;
+ case SS_CONNECTED:
+ err = -EISCONN;
+ goto out;
+ case SS_CONNECTING:
+ err = -EALREADY;
+ /* Fall out of switch with err, set for this state */
+ break;
+ case SS_UNCONNECTED:
+ err = -EISCONN;
+ if (sk->sk_state != TCP_CLOSE)
+ goto out;
+
+ err = sk->sk_prot->connect(sk, uaddr, addr_len);
+ if (err < 0)
+ goto out;
+
+ sock->state = SS_CONNECTING;
+
+ /* Just entered SS_CONNECTING state; the only
+ * difference is that return value in non-blocking
+ * case is EINPROGRESS, rather than EALREADY.
+ */
+ err = -EINPROGRESS;
+ break;
+ }
+
+ timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+ if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
+ /* Error code is set above */
+ if (!timeo || !inet_wait_for_connect(sk, timeo))
+ goto out;
+
+ err = sock_intr_errno(timeo);
+ if (signal_pending(current))
+ goto out;
+ }
+
+ /* Connection was closed by RST, timeout, ICMP error
+ * or another process disconnected us.
+ */
+ if (sk->sk_state == TCP_CLOSE)
+ goto sock_error;
+
+ /* sk->sk_err may be not zero now, if RECVERR was ordered by user
+ * and error was received after socket entered established state.
+ * Hence, it is handled normally after connect() return successfully.
+ */
+
+ sock->state = SS_CONNECTED;
+ err = 0;
+out:
+ release_sock(sk);
+ return err;
+
+sock_error:
+ err = sock_error(sk) ? : -ECONNABORTED;
+ sock->state = SS_UNCONNECTED;
+ if (sk->sk_prot->disconnect(sk, flags))
+ sock->state = SS_DISCONNECTING;
+ goto out;
+}
+
+/*
+ * Accept a pending connection. The TCP layer now gives BSD semantics.
+ */
+
+int inet_accept(struct socket *sock, struct socket *newsock, int flags)
+{
+ struct sock *sk1 = sock->sk;
+ int err = -EINVAL;
+ struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err);
+
+ if (!sk2)
+ goto do_err;
+
+ lock_sock(sk2);
+
+ BUG_TRAP((1 << sk2->sk_state) &
+ (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_CLOSE));
+
+ sock_graft(sk2, newsock);
+
+ newsock->state = SS_CONNECTED;
+ err = 0;
+ release_sock(sk2);
+do_err:
+ return err;
+}
+
+
+/*
+ * This does both peername and sockname.
+ */
+int inet_getname(struct socket *sock, struct sockaddr *uaddr,
+ int *uaddr_len, int peer)
+{
+ struct sock *sk = sock->sk;
+ struct inet_sock *inet = inet_sk(sk);
+ struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
+
+ sin->sin_family = AF_INET;
+ if (peer) {
+ if (!inet->dport ||
+ (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
+ peer == 1))
+ return -ENOTCONN;
+ sin->sin_port = inet->dport;
+ sin->sin_addr.s_addr = inet->daddr;
+ } else {
+ __u32 addr = inet->rcv_saddr;
+ if (!addr)
+ addr = inet->saddr;
+ sin->sin_port = inet->sport;
+ sin->sin_addr.s_addr = addr;
+ }
+ memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
+ *uaddr_len = sizeof(*sin);
+ return 0;
+}
+
+int inet_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
+ size_t size)
+{
+ struct sock *sk = sock->sk;
+
+ /* We may need to bind the socket. */
+ if (!inet_sk(sk)->num && inet_autobind(sk))
+ return -EAGAIN;
+
+ return sk->sk_prot->sendmsg(iocb, sk, msg, size);
+}
+
+
+static ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
+{
+ struct sock *sk = sock->sk;
+
+ /* We may need to bind the socket. */
+ if (!inet_sk(sk)->num && inet_autobind(sk))
+ return -EAGAIN;
+
+ if (sk->sk_prot->sendpage)
+ return sk->sk_prot->sendpage(sk, page, offset, size, flags);
+ return sock_no_sendpage(sock, page, offset, size, flags);
+}
+
+
+int inet_shutdown(struct socket *sock, int how)
+{
+ struct sock *sk = sock->sk;
+ int err = 0;
+
+ /* This should really check to make sure
+ * the socket is a TCP socket. (WHY AC...)
+ */
+ how++; /* maps 0->1 has the advantage of making bit 1 rcvs and
+ 1->2 bit 2 snds.
+ 2->3 */
+ if ((how & ~SHUTDOWN_MASK) || !how) /* MAXINT->0 */
+ return -EINVAL;
+
+ lock_sock(sk);
+ if (sock->state == SS_CONNECTING) {
+ if ((1 << sk->sk_state) &
+ (TCPF_SYN_SENT | TCPF_SYN_RECV | TCPF_CLOSE))
+ sock->state = SS_DISCONNECTING;
+ else
+ sock->state = SS_CONNECTED;
+ }
+
+ switch (sk->sk_state) {
+ case TCP_CLOSE:
+ err = -ENOTCONN;
+ /* Hack to wake up other listeners, who can poll for
+ POLLHUP, even on eg. unconnected UDP sockets -- RR */
+ default:
+ sk->sk_shutdown |= how;
+ if (sk->sk_prot->shutdown)
+ sk->sk_prot->shutdown(sk, how);
+ break;
+
+ /* Remaining two branches are temporary solution for missing
+ * close() in multithreaded environment. It is _not_ a good idea,
+ * but we have no choice until close() is repaired at VFS level.
+ */
+ case TCP_LISTEN:
+ if (!(how & RCV_SHUTDOWN))
+ break;
+ /* Fall through */
+ case TCP_SYN_SENT:
+ err = sk->sk_prot->disconnect(sk, O_NONBLOCK);
+ sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED;
+ break;
+ }
+
+ /* Wake up anyone sleeping in poll. */
+ sk->sk_state_change(sk);
+ release_sock(sk);
+ return err;
+}
+
+/*
+ * ioctl() calls you can issue on an INET socket. Most of these are
+ * device configuration and stuff and very rarely used. Some ioctls
+ * pass on to the socket itself.
+ *
+ * NOTE: I like the idea of a module for the config stuff. ie ifconfig
+ * loads the devconfigure module does its configuring and unloads it.
+ * There's a good 20K of config code hanging around the kernel.
+ */
+
+int inet_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+ int err = 0;
+
+ switch (cmd) {
+ case SIOCGSTAMP:
+ err = sock_get_timestamp(sk, (struct timeval __user *)arg);
+ break;
+ case SIOCADDRT:
+ case SIOCDELRT:
+ case SIOCRTMSG:
+ err = ip_rt_ioctl(cmd, (void __user *)arg);
+ break;
+ case SIOCDARP:
+ case SIOCGARP:
+ case SIOCSARP:
+ err = arp_ioctl(cmd, (void __user *)arg);
+ break;
+ case SIOCGIFADDR:
+ case SIOCSIFADDR:
+ case SIOCGIFBRDADDR:
+ case SIOCSIFBRDADDR:
+ case SIOCGIFNETMASK:
+ case SIOCSIFNETMASK:
+ case SIOCGIFDSTADDR:
+ case SIOCSIFDSTADDR:
+ case SIOCSIFPFLAGS:
+ case SIOCGIFPFLAGS:
+ case SIOCSIFFLAGS:
+ err = devinet_ioctl(cmd, (void __user *)arg);
+ break;
+ default:
+ if (!sk->sk_prot->ioctl ||
+ (err = sk->sk_prot->ioctl(sk, cmd, arg)) ==
+ -ENOIOCTLCMD)
+ err = dev_ioctl(cmd, (void __user *)arg);
+ break;
+ }
+ return err;
+}
+
+struct proto_ops inet_stream_ops = {
+ .family = PF_INET,
+ .owner = THIS_MODULE,
+ .release = inet_release,
+ .bind = inet_bind,
+ .connect = inet_stream_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = inet_accept,
+ .getname = inet_getname,
+ .poll = tcp_poll,
+ .ioctl = inet_ioctl,
+ .listen = inet_listen,
+ .shutdown = inet_shutdown,
+ .setsockopt = sock_common_setsockopt,
+ .getsockopt = sock_common_getsockopt,
+ .sendmsg = inet_sendmsg,
+ .recvmsg = sock_common_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = tcp_sendpage
+};
+
+struct proto_ops inet_dgram_ops = {
+ .family = PF_INET,
+ .owner = THIS_MODULE,
+ .release = inet_release,
+ .bind = inet_bind,
+ .connect = inet_dgram_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = inet_getname,
+ .poll = udp_poll,
+ .ioctl = inet_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = inet_shutdown,
+ .setsockopt = sock_common_setsockopt,
+ .getsockopt = sock_common_getsockopt,
+ .sendmsg = inet_sendmsg,
+ .recvmsg = sock_common_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = inet_sendpage,
+};
+
+/*
+ * For SOCK_RAW sockets; should be the same as inet_dgram_ops but without
+ * udp_poll
+ */
+static struct proto_ops inet_sockraw_ops = {
+ .family = PF_INET,
+ .owner = THIS_MODULE,
+ .release = inet_release,
+ .bind = inet_bind,
+ .connect = inet_dgram_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = inet_getname,
+ .poll = datagram_poll,
+ .ioctl = inet_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = inet_shutdown,
+ .setsockopt = sock_common_setsockopt,
+ .getsockopt = sock_common_getsockopt,
+ .sendmsg = inet_sendmsg,
+ .recvmsg = sock_common_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = inet_sendpage,
+};
+
+static struct net_proto_family inet_family_ops = {
+ .family = PF_INET,
+ .create = inet_create,
+ .owner = THIS_MODULE,
+};
+
+
+extern void tcp_init(void);
+extern void tcp_v4_init(struct net_proto_family *);
+
+/* Upon startup we insert all the elements in inetsw_array[] into
+ * the linked list inetsw.
+ */
+static struct inet_protosw inetsw_array[] =
+{
+ {
+ .type = SOCK_STREAM,
+ .protocol = IPPROTO_TCP,
+ .prot = &tcp_prot,
+ .ops = &inet_stream_ops,
+ .capability = -1,
+ .no_check = 0,
+ .flags = INET_PROTOSW_PERMANENT,
+ },
+
+ {
+ .type = SOCK_DGRAM,
+ .protocol = IPPROTO_UDP,
+ .prot = &udp_prot,
+ .ops = &inet_dgram_ops,
+ .capability = -1,
+ .no_check = UDP_CSUM_DEFAULT,
+ .flags = INET_PROTOSW_PERMANENT,
+ },
+
+
+ {
+ .type = SOCK_RAW,
+ .protocol = IPPROTO_IP, /* wild card */
+ .prot = &raw_prot,
+ .ops = &inet_sockraw_ops,
+ .capability = CAP_NET_RAW,
+ .no_check = UDP_CSUM_DEFAULT,
+ .flags = INET_PROTOSW_REUSE,
+ }
+};
+
+#define INETSW_ARRAY_LEN (sizeof(inetsw_array) / sizeof(struct inet_protosw))
+
+void inet_register_protosw(struct inet_protosw *p)
+{
+ struct list_head *lh;
+ struct inet_protosw *answer;
+ int protocol = p->protocol;
+ struct list_head *last_perm;
+
+ spin_lock_bh(&inetsw_lock);
+
+ if (p->type >= SOCK_MAX)
+ goto out_illegal;
+
+ /* If we are trying to override a permanent protocol, bail. */
+ answer = NULL;
+ last_perm = &inetsw[p->type];
+ list_for_each(lh, &inetsw[p->type]) {
+ answer = list_entry(lh, struct inet_protosw, list);
+
+ /* Check only the non-wild match. */
+ if (INET_PROTOSW_PERMANENT & answer->flags) {
+ if (protocol == answer->protocol)
+ break;
+ last_perm = lh;
+ }
+
+ answer = NULL;
+ }
+ if (answer)
+ goto out_permanent;
+
+ /* Add the new entry after the last permanent entry if any, so that
+ * the new entry does not override a permanent entry when matched with
+ * a wild-card protocol. But it is allowed to override any existing
+ * non-permanent entry. This means that when we remove this entry, the
+ * system automatically returns to the old behavior.
+ */
+ list_add_rcu(&p->list, last_perm);
+out:
+ spin_unlock_bh(&inetsw_lock);
+
+ synchronize_net();
+
+ return;
+
+out_permanent:
+ printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
+ protocol);
+ goto out;
+
+out_illegal:
+ printk(KERN_ERR
+ "Ignoring attempt to register invalid socket type %d.\n",
+ p->type);
+ goto out;
+}
+
+void inet_unregister_protosw(struct inet_protosw *p)
+{
+ if (INET_PROTOSW_PERMANENT & p->flags) {
+ printk(KERN_ERR
+ "Attempt to unregister permanent protocol %d.\n",
+ p->protocol);
+ } else {
+ spin_lock_bh(&inetsw_lock);
+ list_del_rcu(&p->list);
+ spin_unlock_bh(&inetsw_lock);
+
+ synchronize_net();
+ }
+}
+
+#ifdef CONFIG_IP_MULTICAST
+static struct net_protocol igmp_protocol = {
+ .handler = igmp_rcv,
+};
+#endif
+
+static struct net_protocol tcp_protocol = {
+ .handler = tcp_v4_rcv,
+ .err_handler = tcp_v4_err,
+ .no_policy = 1,
+};
+
+static struct net_protocol udp_protocol = {
+ .handler = udp_rcv,
+ .err_handler = udp_err,
+ .no_policy = 1,
+};
+
+static struct net_protocol icmp_protocol = {
+ .handler = icmp_rcv,
+};
+
+static int __init init_ipv4_mibs(void)
+{
+ net_statistics[0] = alloc_percpu(struct linux_mib);
+ net_statistics[1] = alloc_percpu(struct linux_mib);
+ ip_statistics[0] = alloc_percpu(struct ipstats_mib);
+ ip_statistics[1] = alloc_percpu(struct ipstats_mib);
+ icmp_statistics[0] = alloc_percpu(struct icmp_mib);
+ icmp_statistics[1] = alloc_percpu(struct icmp_mib);
+ tcp_statistics[0] = alloc_percpu(struct tcp_mib);
+ tcp_statistics[1] = alloc_percpu(struct tcp_mib);
+ udp_statistics[0] = alloc_percpu(struct udp_mib);
+ udp_statistics[1] = alloc_percpu(struct udp_mib);
+ if (!
+ (net_statistics[0] && net_statistics[1] && ip_statistics[0]
+ && ip_statistics[1] && tcp_statistics[0] && tcp_statistics[1]
+ && udp_statistics[0] && udp_statistics[1]))
+ return -ENOMEM;
+
+ (void) tcp_mib_init();
+
+ return 0;
+}
+
+static int ipv4_proc_init(void);
+extern void ipfrag_init(void);
+
+static int __init inet_init(void)
+{
+ struct sk_buff *dummy_skb;
+ struct inet_protosw *q;
+ struct list_head *r;
+ int rc = -EINVAL;
+
+ if (sizeof(struct inet_skb_parm) > sizeof(dummy_skb->cb)) {
+ printk(KERN_CRIT "%s: panic\n", __FUNCTION__);
+ goto out;
+ }
+
+ rc = proto_register(&tcp_prot, 1);
+ if (rc)
+ goto out;
+
+ rc = proto_register(&udp_prot, 1);
+ if (rc)
+ goto out_unregister_tcp_proto;
+
+ rc = proto_register(&raw_prot, 1);
+ if (rc)
+ goto out_unregister_udp_proto;
+
+ /*
+ * Tell SOCKET that we are alive...
+ */
+
+ (void)sock_register(&inet_family_ops);
+
+ /*
+ * Add all the base protocols.
+ */
+
+ if (inet_add_protocol(&icmp_protocol, IPPROTO_ICMP) < 0)
+ printk(KERN_CRIT "inet_init: Cannot add ICMP protocol\n");
+ if (inet_add_protocol(&udp_protocol, IPPROTO_UDP) < 0)
+ printk(KERN_CRIT "inet_init: Cannot add UDP protocol\n");
+ if (inet_add_protocol(&tcp_protocol, IPPROTO_TCP) < 0)
+ printk(KERN_CRIT "inet_init: Cannot add TCP protocol\n");
+#ifdef CONFIG_IP_MULTICAST
+ if (inet_add_protocol(&igmp_protocol, IPPROTO_IGMP) < 0)
+ printk(KERN_CRIT "inet_init: Cannot add IGMP protocol\n");
+#endif
+
+ /* Register the socket-side information for inet_create. */
+ for (r = &inetsw[0]; r < &inetsw[SOCK_MAX]; ++r)
+ INIT_LIST_HEAD(r);
+
+ for (q = inetsw_array; q < &inetsw_array[INETSW_ARRAY_LEN]; ++q)
+ inet_register_protosw(q);
+
+ /*
+ * Set the ARP module up
+ */
+
+ arp_init();
+
+ /*
+ * Set the IP module up
+ */
+
+ ip_init();
+
+ tcp_v4_init(&inet_family_ops);
+
+ /* Setup TCP slab cache for open requests. */
+ tcp_init();
+
+
+ /*
+ * Set the ICMP layer up
+ */
+
+ icmp_init(&inet_family_ops);
+
+ /*
+ * Initialise the multicast router
+ */
+#if defined(CONFIG_IP_MROUTE)
+ ip_mr_init();
+#endif
+ /*
+ * Initialise per-cpu ipv4 mibs
+ */
+
+ if(init_ipv4_mibs())
+ printk(KERN_CRIT "inet_init: Cannot init ipv4 mibs\n"); ;
+
+ ipv4_proc_init();
+
+ ipfrag_init();
+
+ rc = 0;
+out:
+ return rc;
+out_unregister_tcp_proto:
+ proto_unregister(&tcp_prot);
+out_unregister_udp_proto:
+ proto_unregister(&udp_prot);
+ goto out;
+}
+
+module_init(inet_init);
+
+/* ------------------------------------------------------------------------ */
+
+#ifdef CONFIG_PROC_FS
+extern int fib_proc_init(void);
+extern void fib_proc_exit(void);
+extern int ip_misc_proc_init(void);
+extern int raw_proc_init(void);
+extern void raw_proc_exit(void);
+extern int tcp4_proc_init(void);
+extern void tcp4_proc_exit(void);
+extern int udp4_proc_init(void);
+extern void udp4_proc_exit(void);
+
+static int __init ipv4_proc_init(void)
+{
+ int rc = 0;
+
+ if (raw_proc_init())
+ goto out_raw;
+ if (tcp4_proc_init())
+ goto out_tcp;
+ if (udp4_proc_init())
+ goto out_udp;
+ if (fib_proc_init())
+ goto out_fib;
+ if (ip_misc_proc_init())
+ goto out_misc;
+out:
+ return rc;
+out_misc:
+ fib_proc_exit();
+out_fib:
+ udp4_proc_exit();
+out_udp:
+ tcp4_proc_exit();
+out_tcp:
+ raw_proc_exit();
+out_raw:
+ rc = -ENOMEM;
+ goto out;
+}
+
+#else /* CONFIG_PROC_FS */
+static int __init ipv4_proc_init(void)
+{
+ return 0;
+}
+#endif /* CONFIG_PROC_FS */
+
+MODULE_ALIAS_NETPROTO(PF_INET);
+
+EXPORT_SYMBOL(inet_accept);
+EXPORT_SYMBOL(inet_bind);
+EXPORT_SYMBOL(inet_dgram_connect);
+EXPORT_SYMBOL(inet_dgram_ops);
+EXPORT_SYMBOL(inet_getname);
+EXPORT_SYMBOL(inet_ioctl);
+EXPORT_SYMBOL(inet_listen);
+EXPORT_SYMBOL(inet_register_protosw);
+EXPORT_SYMBOL(inet_release);
+EXPORT_SYMBOL(inet_sendmsg);
+EXPORT_SYMBOL(inet_shutdown);
+EXPORT_SYMBOL(inet_sock_destruct);
+EXPORT_SYMBOL(inet_stream_connect);
+EXPORT_SYMBOL(inet_stream_ops);
+EXPORT_SYMBOL(inet_unregister_protosw);
+EXPORT_SYMBOL(net_statistics);
+
+#ifdef INET_REFCNT_DEBUG
+EXPORT_SYMBOL(inet_sock_nr);
+#endif