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authorrgrimes <rgrimes@FreeBSD.org>1994-05-24 10:09:53 +0000
committerrgrimes <rgrimes@FreeBSD.org>1994-05-24 10:09:53 +0000
commit8fb65ce818b3e3c6f165b583b910af24000768a5 (patch)
treeba751e4f2166aefec707c9d7401c7ff432506642 /sys/netinet/tcp_usrreq.c
parenta6ce65d368e623088a4c1a29865889f431b15420 (diff)
downloadFreeBSD-src-8fb65ce818b3e3c6f165b583b910af24000768a5.zip
FreeBSD-src-8fb65ce818b3e3c6f165b583b910af24000768a5.tar.gz
BSD 4.4 Lite Kernel Sources
Diffstat (limited to 'sys/netinet/tcp_usrreq.c')
-rw-r--r--sys/netinet/tcp_usrreq.c517
1 files changed, 517 insertions, 0 deletions
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
new file mode 100644
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+/*
+ * Copyright (c) 1982, 1986, 1988, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+ *
+ * @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/protosw.h>
+#include <sys/errno.h>
+#include <sys/stat.h>
+
+#include <net/if.h>
+#include <net/route.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/in_pcb.h>
+#include <netinet/ip_var.h>
+#include <netinet/tcp.h>
+#include <netinet/tcp_fsm.h>
+#include <netinet/tcp_seq.h>
+#include <netinet/tcp_timer.h>
+#include <netinet/tcp_var.h>
+#include <netinet/tcpip.h>
+#include <netinet/tcp_debug.h>
+
+/*
+ * TCP protocol interface to socket abstraction.
+ */
+extern char *tcpstates[];
+
+/*
+ * Process a TCP user request for TCP tb. If this is a send request
+ * then m is the mbuf chain of send data. If this is a timer expiration
+ * (called from the software clock routine), then timertype tells which timer.
+ */
+/*ARGSUSED*/
+int
+tcp_usrreq(so, req, m, nam, control)
+ struct socket *so;
+ int req;
+ struct mbuf *m, *nam, *control;
+{
+ register struct inpcb *inp;
+ register struct tcpcb *tp;
+ int s;
+ int error = 0;
+ int ostate;
+
+ if (req == PRU_CONTROL)
+ return (in_control(so, (int)m, (caddr_t)nam,
+ (struct ifnet *)control));
+ if (control && control->m_len) {
+ m_freem(control);
+ if (m)
+ m_freem(m);
+ return (EINVAL);
+ }
+
+ s = splnet();
+ inp = sotoinpcb(so);
+ /*
+ * When a TCP is attached to a socket, then there will be
+ * a (struct inpcb) pointed at by the socket, and this
+ * structure will point at a subsidary (struct tcpcb).
+ */
+ if (inp == 0 && req != PRU_ATTACH) {
+ splx(s);
+ return (EINVAL); /* XXX */
+ }
+ if (inp) {
+ tp = intotcpcb(inp);
+ /* WHAT IF TP IS 0? */
+#ifdef KPROF
+ tcp_acounts[tp->t_state][req]++;
+#endif
+ ostate = tp->t_state;
+ } else
+ ostate = 0;
+ switch (req) {
+
+ /*
+ * TCP attaches to socket via PRU_ATTACH, reserving space,
+ * and an internet control block.
+ */
+ case PRU_ATTACH:
+ if (inp) {
+ error = EISCONN;
+ break;
+ }
+ error = tcp_attach(so);
+ if (error)
+ break;
+ if ((so->so_options & SO_LINGER) && so->so_linger == 0)
+ so->so_linger = TCP_LINGERTIME;
+ tp = sototcpcb(so);
+ break;
+
+ /*
+ * PRU_DETACH detaches the TCP protocol from the socket.
+ * If the protocol state is non-embryonic, then can't
+ * do this directly: have to initiate a PRU_DISCONNECT,
+ * which may finish later; embryonic TCB's can just
+ * be discarded here.
+ */
+ case PRU_DETACH:
+ if (tp->t_state > TCPS_LISTEN)
+ tp = tcp_disconnect(tp);
+ else
+ tp = tcp_close(tp);
+ break;
+
+ /*
+ * Give the socket an address.
+ */
+ case PRU_BIND:
+ error = in_pcbbind(inp, nam);
+ if (error)
+ break;
+ break;
+
+ /*
+ * Prepare to accept connections.
+ */
+ case PRU_LISTEN:
+ if (inp->inp_lport == 0)
+ error = in_pcbbind(inp, (struct mbuf *)0);
+ if (error == 0)
+ tp->t_state = TCPS_LISTEN;
+ break;
+
+ /*
+ * Initiate connection to peer.
+ * Create a template for use in transmissions on this connection.
+ * Enter SYN_SENT state, and mark socket as connecting.
+ * Start keep-alive timer, and seed output sequence space.
+ * Send initial segment on connection.
+ */
+ case PRU_CONNECT:
+ if (inp->inp_lport == 0) {
+ error = in_pcbbind(inp, (struct mbuf *)0);
+ if (error)
+ break;
+ }
+ error = in_pcbconnect(inp, nam);
+ if (error)
+ break;
+ tp->t_template = tcp_template(tp);
+ if (tp->t_template == 0) {
+ in_pcbdisconnect(inp);
+ error = ENOBUFS;
+ break;
+ }
+ /* Compute window scaling to request. */
+ while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
+ (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
+ tp->request_r_scale++;
+ soisconnecting(so);
+ tcpstat.tcps_connattempt++;
+ tp->t_state = TCPS_SYN_SENT;
+ tp->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT;
+ tp->iss = tcp_iss; tcp_iss += TCP_ISSINCR/2;
+ tcp_sendseqinit(tp);
+ error = tcp_output(tp);
+ break;
+
+ /*
+ * Create a TCP connection between two sockets.
+ */
+ case PRU_CONNECT2:
+ error = EOPNOTSUPP;
+ break;
+
+ /*
+ * Initiate disconnect from peer.
+ * If connection never passed embryonic stage, just drop;
+ * else if don't need to let data drain, then can just drop anyways,
+ * else have to begin TCP shutdown process: mark socket disconnecting,
+ * drain unread data, state switch to reflect user close, and
+ * send segment (e.g. FIN) to peer. Socket will be really disconnected
+ * when peer sends FIN and acks ours.
+ *
+ * SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
+ */
+ case PRU_DISCONNECT:
+ tp = tcp_disconnect(tp);
+ break;
+
+ /*
+ * Accept a connection. Essentially all the work is
+ * done at higher levels; just return the address
+ * of the peer, storing through addr.
+ */
+ case PRU_ACCEPT:
+ in_setpeeraddr(inp, nam);
+ break;
+
+ /*
+ * Mark the connection as being incapable of further output.
+ */
+ case PRU_SHUTDOWN:
+ socantsendmore(so);
+ tp = tcp_usrclosed(tp);
+ if (tp)
+ error = tcp_output(tp);
+ break;
+
+ /*
+ * After a receive, possibly send window update to peer.
+ */
+ case PRU_RCVD:
+ (void) tcp_output(tp);
+ break;
+
+ /*
+ * Do a send by putting data in output queue and updating urgent
+ * marker if URG set. Possibly send more data.
+ */
+ case PRU_SEND:
+ sbappend(&so->so_snd, m);
+ error = tcp_output(tp);
+ break;
+
+ /*
+ * Abort the TCP.
+ */
+ case PRU_ABORT:
+ tp = tcp_drop(tp, ECONNABORTED);
+ break;
+
+ case PRU_SENSE:
+ ((struct stat *) m)->st_blksize = so->so_snd.sb_hiwat;
+ (void) splx(s);
+ return (0);
+
+ case PRU_RCVOOB:
+ if ((so->so_oobmark == 0 &&
+ (so->so_state & SS_RCVATMARK) == 0) ||
+ so->so_options & SO_OOBINLINE ||
+ tp->t_oobflags & TCPOOB_HADDATA) {
+ error = EINVAL;
+ break;
+ }
+ if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
+ error = EWOULDBLOCK;
+ break;
+ }
+ m->m_len = 1;
+ *mtod(m, caddr_t) = tp->t_iobc;
+ if (((int)nam & MSG_PEEK) == 0)
+ tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
+ break;
+
+ case PRU_SENDOOB:
+ if (sbspace(&so->so_snd) < -512) {
+ m_freem(m);
+ error = ENOBUFS;
+ break;
+ }
+ /*
+ * According to RFC961 (Assigned Protocols),
+ * the urgent pointer points to the last octet
+ * of urgent data. We continue, however,
+ * to consider it to indicate the first octet
+ * of data past the urgent section.
+ * Otherwise, snd_up should be one lower.
+ */
+ sbappend(&so->so_snd, m);
+ tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
+ tp->t_force = 1;
+ error = tcp_output(tp);
+ tp->t_force = 0;
+ break;
+
+ case PRU_SOCKADDR:
+ in_setsockaddr(inp, nam);
+ break;
+
+ case PRU_PEERADDR:
+ in_setpeeraddr(inp, nam);
+ break;
+
+ /*
+ * TCP slow timer went off; going through this
+ * routine for tracing's sake.
+ */
+ case PRU_SLOWTIMO:
+ tp = tcp_timers(tp, (int)nam);
+ req |= (int)nam << 8; /* for debug's sake */
+ break;
+
+ default:
+ panic("tcp_usrreq");
+ }
+ if (tp && (so->so_options & SO_DEBUG))
+ tcp_trace(TA_USER, ostate, tp, (struct tcpiphdr *)0, req);
+ splx(s);
+ return (error);
+}
+
+int
+tcp_ctloutput(op, so, level, optname, mp)
+ int op;
+ struct socket *so;
+ int level, optname;
+ struct mbuf **mp;
+{
+ int error = 0, s;
+ struct inpcb *inp;
+ register struct tcpcb *tp;
+ register struct mbuf *m;
+ register int i;
+
+ s = splnet();
+ inp = sotoinpcb(so);
+ if (inp == NULL) {
+ splx(s);
+ if (op == PRCO_SETOPT && *mp)
+ (void) m_free(*mp);
+ return (ECONNRESET);
+ }
+ if (level != IPPROTO_TCP) {
+ error = ip_ctloutput(op, so, level, optname, mp);
+ splx(s);
+ return (error);
+ }
+ tp = intotcpcb(inp);
+
+ switch (op) {
+
+ case PRCO_SETOPT:
+ m = *mp;
+ switch (optname) {
+
+ case TCP_NODELAY:
+ if (m == NULL || m->m_len < sizeof (int))
+ error = EINVAL;
+ else if (*mtod(m, int *))
+ tp->t_flags |= TF_NODELAY;
+ else
+ tp->t_flags &= ~TF_NODELAY;
+ break;
+
+ case TCP_MAXSEG:
+ if (m && (i = *mtod(m, int *)) > 0 && i <= tp->t_maxseg)
+ tp->t_maxseg = i;
+ else
+ error = EINVAL;
+ break;
+
+ default:
+ error = ENOPROTOOPT;
+ break;
+ }
+ if (m)
+ (void) m_free(m);
+ break;
+
+ case PRCO_GETOPT:
+ *mp = m = m_get(M_WAIT, MT_SOOPTS);
+ m->m_len = sizeof(int);
+
+ switch (optname) {
+ case TCP_NODELAY:
+ *mtod(m, int *) = tp->t_flags & TF_NODELAY;
+ break;
+ case TCP_MAXSEG:
+ *mtod(m, int *) = tp->t_maxseg;
+ break;
+ default:
+ error = ENOPROTOOPT;
+ break;
+ }
+ break;
+ }
+ splx(s);
+ return (error);
+}
+
+u_long tcp_sendspace = 1024*8;
+u_long tcp_recvspace = 1024*8;
+
+/*
+ * Attach TCP protocol to socket, allocating
+ * internet protocol control block, tcp control block,
+ * bufer space, and entering LISTEN state if to accept connections.
+ */
+int
+tcp_attach(so)
+ struct socket *so;
+{
+ register struct tcpcb *tp;
+ struct inpcb *inp;
+ int error;
+
+ if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
+ error = soreserve(so, tcp_sendspace, tcp_recvspace);
+ if (error)
+ return (error);
+ }
+ error = in_pcballoc(so, &tcb);
+ if (error)
+ return (error);
+ inp = sotoinpcb(so);
+ tp = tcp_newtcpcb(inp);
+ if (tp == 0) {
+ int nofd = so->so_state & SS_NOFDREF; /* XXX */
+
+ so->so_state &= ~SS_NOFDREF; /* don't free the socket yet */
+ in_pcbdetach(inp);
+ so->so_state |= nofd;
+ return (ENOBUFS);
+ }
+ tp->t_state = TCPS_CLOSED;
+ return (0);
+}
+
+/*
+ * Initiate (or continue) disconnect.
+ * If embryonic state, just send reset (once).
+ * If in ``let data drain'' option and linger null, just drop.
+ * Otherwise (hard), mark socket disconnecting and drop
+ * current input data; switch states based on user close, and
+ * send segment to peer (with FIN).
+ */
+struct tcpcb *
+tcp_disconnect(tp)
+ register struct tcpcb *tp;
+{
+ struct socket *so = tp->t_inpcb->inp_socket;
+
+ if (tp->t_state < TCPS_ESTABLISHED)
+ tp = tcp_close(tp);
+ else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
+ tp = tcp_drop(tp, 0);
+ else {
+ soisdisconnecting(so);
+ sbflush(&so->so_rcv);
+ tp = tcp_usrclosed(tp);
+ if (tp)
+ (void) tcp_output(tp);
+ }
+ return (tp);
+}
+
+/*
+ * User issued close, and wish to trail through shutdown states:
+ * if never received SYN, just forget it. If got a SYN from peer,
+ * but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
+ * If already got a FIN from peer, then almost done; go to LAST_ACK
+ * state. In all other cases, have already sent FIN to peer (e.g.
+ * after PRU_SHUTDOWN), and just have to play tedious game waiting
+ * for peer to send FIN or not respond to keep-alives, etc.
+ * We can let the user exit from the close as soon as the FIN is acked.
+ */
+struct tcpcb *
+tcp_usrclosed(tp)
+ register struct tcpcb *tp;
+{
+
+ switch (tp->t_state) {
+
+ case TCPS_CLOSED:
+ case TCPS_LISTEN:
+ case TCPS_SYN_SENT:
+ tp->t_state = TCPS_CLOSED;
+ tp = tcp_close(tp);
+ break;
+
+ case TCPS_SYN_RECEIVED:
+ case TCPS_ESTABLISHED:
+ tp->t_state = TCPS_FIN_WAIT_1;
+ break;
+
+ case TCPS_CLOSE_WAIT:
+ tp->t_state = TCPS_LAST_ACK;
+ break;
+ }
+ if (tp && tp->t_state >= TCPS_FIN_WAIT_2)
+ soisdisconnected(tp->t_inpcb->inp_socket);
+ return (tp);
+}
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