diff options
Diffstat (limited to 'sys/netinet/tcp_usrreq.c')
| -rw-r--r-- | sys/netinet/tcp_usrreq.c | 1151 |
1 files changed, 1151 insertions, 0 deletions
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c new file mode 100644 index 0000000..25834d4 --- /dev/null +++ b/sys/netinet/tcp_usrreq.c @@ -0,0 +1,1151 @@ +/* + * 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. + * + * From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94 + * $FreeBSD$ + */ + +#include "opt_ipsec.h" +#include "opt_inet6.h" +#include "opt_tcpdebug.h" + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/sysctl.h> +#include <sys/mbuf.h> +#ifdef INET6 +#include <sys/domain.h> +#endif /* INET6 */ +#include <sys/socket.h> +#include <sys/socketvar.h> +#include <sys/protosw.h> +#include <sys/proc.h> +#include <sys/jail.h> + +#include <net/if.h> +#include <net/route.h> + +#include <netinet/in.h> +#include <netinet/in_systm.h> +#ifdef INET6 +#include <netinet/ip6.h> +#endif +#include <netinet/in_pcb.h> +#ifdef INET6 +#include <netinet6/in6_pcb.h> +#endif +#include <netinet/in_var.h> +#include <netinet/ip_var.h> +#ifdef INET6 +#include <netinet6/ip6_var.h> +#endif +#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> +#ifdef TCPDEBUG +#include <netinet/tcp_debug.h> +#endif + +#ifdef IPSEC +#include <netinet6/ipsec.h> +#endif /*IPSEC*/ + +/* + * TCP protocol interface to socket abstraction. + */ +extern char *tcpstates[]; /* XXX ??? */ + +static int tcp_attach __P((struct socket *, struct proc *)); +static int tcp_connect __P((struct tcpcb *, struct sockaddr *, + struct proc *)); +#ifdef INET6 +static int tcp6_connect __P((struct tcpcb *, struct sockaddr *, + struct proc *)); +#endif /* INET6 */ +static struct tcpcb * + tcp_disconnect __P((struct tcpcb *)); +static struct tcpcb * + tcp_usrclosed __P((struct tcpcb *)); + +#ifdef TCPDEBUG +#define TCPDEBUG0 int ostate = 0 +#define TCPDEBUG1() ostate = tp ? tp->t_state : 0 +#define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \ + tcp_trace(TA_USER, ostate, tp, 0, 0, req) +#else +#define TCPDEBUG0 +#define TCPDEBUG1() +#define TCPDEBUG2(req) +#endif + +/* + * TCP attaches to socket via pru_attach(), reserving space, + * and an internet control block. + */ +static int +tcp_usr_attach(struct socket *so, int proto, struct proc *p) +{ + int s = splnet(); + int error; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp = 0; + TCPDEBUG0; + + TCPDEBUG1(); + if (inp) { + error = EISCONN; + goto out; + } + + error = tcp_attach(so, p); + if (error) + goto out; + + if ((so->so_options & SO_LINGER) && so->so_linger == 0) + so->so_linger = TCP_LINGERTIME; + tp = sototcpcb(so); +out: + TCPDEBUG2(PRU_ATTACH); + splx(s); + return error; +} + +/* + * 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. + */ +static int +tcp_usr_detach(struct socket *so) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + TCPDEBUG0; + + if (inp == 0) { + splx(s); + return EINVAL; /* XXX */ + } + tp = intotcpcb(inp); + TCPDEBUG1(); + tp = tcp_disconnect(tp); + + TCPDEBUG2(PRU_DETACH); + splx(s); + return error; +} + +#define COMMON_START() TCPDEBUG0; \ + do { \ + if (inp == 0) { \ + splx(s); \ + return EINVAL; \ + } \ + tp = intotcpcb(inp); \ + TCPDEBUG1(); \ + } while(0) + +#define COMMON_END(req) out: TCPDEBUG2(req); splx(s); return error; goto out + + +/* + * Give the socket an address. + */ +static int +tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + struct sockaddr_in *sinp; + + COMMON_START(); + + /* + * Must check for multicast addresses and disallow binding + * to them. + */ + sinp = (struct sockaddr_in *)nam; + if (sinp->sin_family == AF_INET && + IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { + error = EAFNOSUPPORT; + goto out; + } + error = in_pcbbind(inp, nam, p); + if (error) + goto out; + COMMON_END(PRU_BIND); + +} + +#ifdef INET6 +static int +tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + struct sockaddr_in6 *sin6p; + + COMMON_START(); + + /* + * Must check for multicast addresses and disallow binding + * to them. + */ + sin6p = (struct sockaddr_in6 *)nam; + if (sin6p->sin6_family == AF_INET6 && + IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { + error = EAFNOSUPPORT; + goto out; + } + inp->inp_vflag &= ~INP_IPV4; + inp->inp_vflag |= INP_IPV6; + if ((inp->inp_flags & IN6P_BINDV6ONLY) == 0) { + + if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr)) + inp->inp_vflag |= INP_IPV4; + else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { + struct sockaddr_in sin; + + in6_sin6_2_sin(&sin, sin6p); + inp->inp_vflag |= INP_IPV4; + inp->inp_vflag &= ~INP_IPV6; + error = in_pcbbind(inp, (struct sockaddr *)&sin, p); + goto out; + } + } + error = in6_pcbbind(inp, nam, p); + if (error) + goto out; + COMMON_END(PRU_BIND); +} +#endif /* INET6 */ + +/* + * Prepare to accept connections. + */ +static int +tcp_usr_listen(struct socket *so, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + if (inp->inp_lport == 0) + error = in_pcbbind(inp, (struct sockaddr *)0, p); + if (error == 0) + tp->t_state = TCPS_LISTEN; + COMMON_END(PRU_LISTEN); +} + +#ifdef INET6 +static int +tcp6_usr_listen(struct socket *so, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + if (inp->inp_lport == 0) { + inp->inp_vflag &= ~INP_IPV4; + if ((inp->inp_flags & IN6P_BINDV6ONLY) == 0) + inp->inp_vflag |= INP_IPV4; + error = in6_pcbbind(inp, (struct sockaddr *)0, p); + } + if (error == 0) + tp->t_state = TCPS_LISTEN; + COMMON_END(PRU_LISTEN); +} +#endif /* INET6 */ + +/* + * 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. + */ +static int +tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + struct sockaddr_in *sinp; + + COMMON_START(); + + /* + * Must disallow TCP ``connections'' to multicast addresses. + */ + sinp = (struct sockaddr_in *)nam; + if (sinp->sin_family == AF_INET + && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) { + error = EAFNOSUPPORT; + goto out; + } + + if (p && jailed(p->p_ucred)) + prison_remote_ip(p->p_ucred, 0, &sinp->sin_addr.s_addr); + + if ((error = tcp_connect(tp, nam, p)) != 0) + goto out; + error = tcp_output(tp); + COMMON_END(PRU_CONNECT); +} + +#ifdef INET6 +static int +tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + struct sockaddr_in6 *sin6p; + + COMMON_START(); + + /* + * Must disallow TCP ``connections'' to multicast addresses. + */ + sin6p = (struct sockaddr_in6 *)nam; + if (sin6p->sin6_family == AF_INET6 + && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) { + error = EAFNOSUPPORT; + goto out; + } + + if ((inp->inp_flags & IN6P_BINDV6ONLY) == 0 && + IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { + struct sockaddr_in sin; + + in6_sin6_2_sin(&sin, sin6p); + inp->inp_vflag |= INP_IPV4; + inp->inp_vflag &= ~INP_IPV6; + if ((error = tcp_connect(tp, (struct sockaddr *)&sin, p)) != 0) + goto out; + error = tcp_output(tp); + goto out; + } + inp->inp_vflag &= ~INP_IPV4; + inp->inp_vflag |= INP_IPV6; + if ((error = tcp6_connect(tp, nam, p)) != 0) + goto out; + error = tcp_output(tp); + COMMON_END(PRU_CONNECT); +} +#endif /* INET6 */ + +/* + * 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. + */ +static int +tcp_usr_disconnect(struct socket *so) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + tp = tcp_disconnect(tp); + COMMON_END(PRU_DISCONNECT); +} + +/* + * Accept a connection. Essentially all the work is + * done at higher levels; just return the address + * of the peer, storing through addr. + */ +static int +tcp_usr_accept(struct socket *so, struct sockaddr **nam) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp = NULL; + TCPDEBUG0; + + if (so->so_state & SS_ISDISCONNECTED) { + error = ECONNABORTED; + goto out; + } + if (inp == 0) { + splx(s); + return (EINVAL); + } + tp = intotcpcb(inp); + TCPDEBUG1(); + in_setpeeraddr(so, nam); + COMMON_END(PRU_ACCEPT); +} + +#ifdef INET6 +static int +tcp6_usr_accept(struct socket *so, struct sockaddr **nam) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp = NULL; + TCPDEBUG0; + + if (so->so_state & SS_ISDISCONNECTED) { + error = ECONNABORTED; + goto out; + } + if (inp == 0) { + splx(s); + return (EINVAL); + } + tp = intotcpcb(inp); + TCPDEBUG1(); + in6_mapped_peeraddr(so, nam); + COMMON_END(PRU_ACCEPT); +} +#endif /* INET6 */ +/* + * Mark the connection as being incapable of further output. + */ +static int +tcp_usr_shutdown(struct socket *so) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + socantsendmore(so); + tp = tcp_usrclosed(tp); + if (tp) + error = tcp_output(tp); + COMMON_END(PRU_SHUTDOWN); +} + +/* + * After a receive, possibly send window update to peer. + */ +static int +tcp_usr_rcvd(struct socket *so, int flags) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + tcp_output(tp); + COMMON_END(PRU_RCVD); +} + +/* + * Do a send by putting data in output queue and updating urgent + * marker if URG set. Possibly send more data. Unlike the other + * pru_*() routines, the mbuf chains are our responsibility. We + * must either enqueue them or free them. The other pru_* routines + * generally are caller-frees. + */ +static int +tcp_usr_send(struct socket *so, int flags, struct mbuf *m, + struct sockaddr *nam, struct mbuf *control, struct proc *p) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; +#ifdef INET6 + int isipv6; +#endif + TCPDEBUG0; + + if (inp == NULL) { + /* + * OOPS! we lost a race, the TCP session got reset after + * we checked SS_CANTSENDMORE, eg: while doing uiomove or a + * network interrupt in the non-splnet() section of sosend(). + */ + if (m) + m_freem(m); + if (control) + m_freem(control); + error = ECONNRESET; /* XXX EPIPE? */ + tp = NULL; + TCPDEBUG1(); + goto out; + } +#ifdef INET6 + isipv6 = nam && nam->sa_family == AF_INET6; +#endif /* INET6 */ + tp = intotcpcb(inp); + TCPDEBUG1(); + if (control) { + /* TCP doesn't do control messages (rights, creds, etc) */ + if (control->m_len) { + m_freem(control); + if (m) + m_freem(m); + error = EINVAL; + goto out; + } + m_freem(control); /* empty control, just free it */ + } + if(!(flags & PRUS_OOB)) { + sbappend(&so->so_snd, m); + if (nam && tp->t_state < TCPS_SYN_SENT) { + /* + * Do implied connect if not yet connected, + * initialize window to default value, and + * initialize maxseg/maxopd using peer's cached + * MSS. + */ +#ifdef INET6 + if (isipv6) + error = tcp6_connect(tp, nam, p); + else +#endif /* INET6 */ + error = tcp_connect(tp, nam, p); + if (error) + goto out; + tp->snd_wnd = TTCP_CLIENT_SND_WND; + tcp_mss(tp, -1); + } + + if (flags & PRUS_EOF) { + /* + * Close the send side of the connection after + * the data is sent. + */ + socantsendmore(so); + tp = tcp_usrclosed(tp); + } + if (tp != NULL) { + if (flags & PRUS_MORETOCOME) + tp->t_flags |= TF_MORETOCOME; + error = tcp_output(tp); + if (flags & PRUS_MORETOCOME) + tp->t_flags &= ~TF_MORETOCOME; + } + } else { + if (sbspace(&so->so_snd) < -512) { + m_freem(m); + error = ENOBUFS; + goto out; + } + /* + * 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); + if (nam && tp->t_state < TCPS_SYN_SENT) { + /* + * Do implied connect if not yet connected, + * initialize window to default value, and + * initialize maxseg/maxopd using peer's cached + * MSS. + */ +#ifdef INET6 + if (isipv6) + error = tcp6_connect(tp, nam, p); + else +#endif /* INET6 */ + error = tcp_connect(tp, nam, p); + if (error) + goto out; + tp->snd_wnd = TTCP_CLIENT_SND_WND; + tcp_mss(tp, -1); + } + tp->snd_up = tp->snd_una + so->so_snd.sb_cc; + tp->t_force = 1; + error = tcp_output(tp); + tp->t_force = 0; + } + COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB : + ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND)); +} + +/* + * Abort the TCP. + */ +static int +tcp_usr_abort(struct socket *so) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + tp = tcp_drop(tp, ECONNABORTED); + COMMON_END(PRU_ABORT); +} + +/* + * Receive out-of-band data. + */ +static int +tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags) +{ + int s = splnet(); + int error = 0; + struct inpcb *inp = sotoinpcb(so); + struct tcpcb *tp; + + COMMON_START(); + if ((so->so_oobmark == 0 && + (so->so_state & SS_RCVATMARK) == 0) || + so->so_options & SO_OOBINLINE || + tp->t_oobflags & TCPOOB_HADDATA) { + error = EINVAL; + goto out; + } + if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) { + error = EWOULDBLOCK; + goto out; + } + m->m_len = 1; + *mtod(m, caddr_t) = tp->t_iobc; + if ((flags & MSG_PEEK) == 0) + tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA); + COMMON_END(PRU_RCVOOB); +} + +/* xxx - should be const */ +struct pr_usrreqs tcp_usrreqs = { + tcp_usr_abort, tcp_usr_accept, tcp_usr_attach, tcp_usr_bind, + tcp_usr_connect, pru_connect2_notsupp, in_control, tcp_usr_detach, + tcp_usr_disconnect, tcp_usr_listen, in_setpeeraddr, tcp_usr_rcvd, + tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown, + in_setsockaddr, sosend, soreceive, sopoll +}; + +#ifdef INET6 +struct pr_usrreqs tcp6_usrreqs = { + tcp_usr_abort, tcp6_usr_accept, tcp_usr_attach, tcp6_usr_bind, + tcp6_usr_connect, pru_connect2_notsupp, in6_control, tcp_usr_detach, + tcp_usr_disconnect, tcp6_usr_listen, in6_mapped_peeraddr, tcp_usr_rcvd, + tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown, + in6_mapped_sockaddr, sosend, soreceive, sopoll +}; +#endif /* INET6 */ + +/* + * Common subroutine to open a TCP connection to remote host specified + * by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local + * port number if needed. Call in_pcbladdr to do the routing and to choose + * a local host address (interface). If there is an existing incarnation + * of the same connection in TIME-WAIT state and if the remote host was + * sending CC options and if the connection duration was < MSL, then + * truncate the previous TIME-WAIT state and proceed. + * Initialize connection parameters and enter SYN-SENT state. + */ +static int +tcp_connect(tp, nam, p) + register struct tcpcb *tp; + struct sockaddr *nam; + struct proc *p; +{ + struct inpcb *inp = tp->t_inpcb, *oinp; + struct socket *so = inp->inp_socket; + struct tcpcb *otp; + struct sockaddr_in *sin = (struct sockaddr_in *)nam; + struct sockaddr_in *ifaddr; + struct rmxp_tao *taop; + struct rmxp_tao tao_noncached; + int error; + + if (inp->inp_lport == 0) { + error = in_pcbbind(inp, (struct sockaddr *)0, p); + if (error) + return error; + } + + /* + * Cannot simply call in_pcbconnect, because there might be an + * earlier incarnation of this same connection still in + * TIME_WAIT state, creating an ADDRINUSE error. + */ + error = in_pcbladdr(inp, nam, &ifaddr); + if (error) + return error; + oinp = in_pcblookup_hash(inp->inp_pcbinfo, + sin->sin_addr, sin->sin_port, + inp->inp_laddr.s_addr != INADDR_ANY ? inp->inp_laddr + : ifaddr->sin_addr, + inp->inp_lport, 0, NULL); + if (oinp) { + if (oinp != inp && (otp = intotcpcb(oinp)) != NULL && + otp->t_state == TCPS_TIME_WAIT && + (ticks - otp->t_starttime) < tcp_msl && + (otp->t_flags & TF_RCVD_CC)) + otp = tcp_close(otp); + else + return EADDRINUSE; + } + if (inp->inp_laddr.s_addr == INADDR_ANY) + inp->inp_laddr = ifaddr->sin_addr; + inp->inp_faddr = sin->sin_addr; + inp->inp_fport = sin->sin_port; + in_pcbrehash(inp); + + tp->t_template = tcp_template(tp); + if (tp->t_template == 0) { + in_pcbdisconnect(inp); + return ENOBUFS; + } + + /* 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; + callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp); + tp->iss = tcp_rndiss_next(); + tcp_sendseqinit(tp); + + /* + * Generate a CC value for this connection and + * check whether CC or CCnew should be used. + */ + if ((taop = tcp_gettaocache(tp->t_inpcb)) == NULL) { + taop = &tao_noncached; + bzero(taop, sizeof(*taop)); + } + + tp->cc_send = CC_INC(tcp_ccgen); + if (taop->tao_ccsent != 0 && + CC_GEQ(tp->cc_send, taop->tao_ccsent)) { + taop->tao_ccsent = tp->cc_send; + } else { + taop->tao_ccsent = 0; + tp->t_flags |= TF_SENDCCNEW; + } + + return 0; +} + +#ifdef INET6 +static int +tcp6_connect(tp, nam, p) + register struct tcpcb *tp; + struct sockaddr *nam; + struct proc *p; +{ + struct inpcb *inp = tp->t_inpcb, *oinp; + struct socket *so = inp->inp_socket; + struct tcpcb *otp; + struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam; + struct in6_addr *addr6; + struct rmxp_tao *taop; + struct rmxp_tao tao_noncached; + int error; + + if (inp->inp_lport == 0) { + error = in6_pcbbind(inp, (struct sockaddr *)0, p); + if (error) + return error; + } + + /* + * Cannot simply call in_pcbconnect, because there might be an + * earlier incarnation of this same connection still in + * TIME_WAIT state, creating an ADDRINUSE error. + */ + error = in6_pcbladdr(inp, nam, &addr6); + if (error) + return error; + oinp = in6_pcblookup_hash(inp->inp_pcbinfo, + &sin6->sin6_addr, sin6->sin6_port, + IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) + ? addr6 + : &inp->in6p_laddr, + inp->inp_lport, 0, NULL); + if (oinp) { + if (oinp != inp && (otp = intotcpcb(oinp)) != NULL && + otp->t_state == TCPS_TIME_WAIT && + (ticks - otp->t_starttime) < tcp_msl && + (otp->t_flags & TF_RCVD_CC)) + otp = tcp_close(otp); + else + return EADDRINUSE; + } + if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) + inp->in6p_laddr = *addr6; + inp->in6p_faddr = sin6->sin6_addr; + inp->inp_fport = sin6->sin6_port; + if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != NULL) + inp->in6p_flowinfo = sin6->sin6_flowinfo; + in_pcbrehash(inp); + + tp->t_template = tcp_template(tp); + if (tp->t_template == 0) { + in6_pcbdisconnect(inp); + return ENOBUFS; + } + + /* 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; + callout_reset(tp->tt_keep, tcp_keepinit, tcp_timer_keep, tp); + tp->iss = tcp_rndiss_next(); + tcp_sendseqinit(tp); + + /* + * Generate a CC value for this connection and + * check whether CC or CCnew should be used. + */ + if ((taop = tcp_gettaocache(tp->t_inpcb)) == NULL) { + taop = &tao_noncached; + bzero(taop, sizeof(*taop)); + } + + tp->cc_send = CC_INC(tcp_ccgen); + if (taop->tao_ccsent != 0 && + CC_GEQ(tp->cc_send, taop->tao_ccsent)) { + taop->tao_ccsent = tp->cc_send; + } else { + taop->tao_ccsent = 0; + tp->t_flags |= TF_SENDCCNEW; + } + + return 0; +} +#endif /* INET6 */ + +/* + * The new sockopt interface makes it possible for us to block in the + * copyin/out step (if we take a page fault). Taking a page fault at + * splnet() is probably a Bad Thing. (Since sockets and pcbs both now + * use TSM, there probably isn't any need for this function to run at + * splnet() any more. This needs more examination.) + */ +int +tcp_ctloutput(so, sopt) + struct socket *so; + struct sockopt *sopt; +{ + int error, opt, optval, s; + struct inpcb *inp; + struct tcpcb *tp; + + error = 0; + s = splnet(); /* XXX */ + inp = sotoinpcb(so); + if (inp == NULL) { + splx(s); + return (ECONNRESET); + } + if (sopt->sopt_level != IPPROTO_TCP) { +#ifdef INET6 + if (INP_CHECK_SOCKAF(so, AF_INET6)) + error = ip6_ctloutput(so, sopt); + else +#endif /* INET6 */ + error = ip_ctloutput(so, sopt); + splx(s); + return (error); + } + tp = intotcpcb(inp); + + switch (sopt->sopt_dir) { + case SOPT_SET: + switch (sopt->sopt_name) { + case TCP_NODELAY: + case TCP_NOOPT: + error = sooptcopyin(sopt, &optval, sizeof optval, + sizeof optval); + if (error) + break; + + switch (sopt->sopt_name) { + case TCP_NODELAY: + opt = TF_NODELAY; + break; + case TCP_NOOPT: + opt = TF_NOOPT; + break; + default: + opt = 0; /* dead code to fool gcc */ + break; + } + + if (optval) + tp->t_flags |= opt; + else + tp->t_flags &= ~opt; + break; + + case TCP_NOPUSH: + error = sooptcopyin(sopt, &optval, sizeof optval, + sizeof optval); + if (error) + break; + + if (optval) + tp->t_flags |= TF_NOPUSH; + else { + tp->t_flags &= ~TF_NOPUSH; + error = tcp_output(tp); + } + break; + + case TCP_MAXSEG: + error = sooptcopyin(sopt, &optval, sizeof optval, + sizeof optval); + if (error) + break; + + if (optval > 0 && optval <= tp->t_maxseg) + tp->t_maxseg = optval; + else + error = EINVAL; + break; + + default: + error = ENOPROTOOPT; + break; + } + break; + + case SOPT_GET: + switch (sopt->sopt_name) { + case TCP_NODELAY: + optval = tp->t_flags & TF_NODELAY; + break; + case TCP_MAXSEG: + optval = tp->t_maxseg; + break; + case TCP_NOOPT: + optval = tp->t_flags & TF_NOOPT; + break; + case TCP_NOPUSH: + optval = tp->t_flags & TF_NOPUSH; + break; + default: + error = ENOPROTOOPT; + break; + } + if (error == 0) + error = sooptcopyout(sopt, &optval, sizeof optval); + break; + } + splx(s); + return (error); +} + +/* + * tcp_sendspace and tcp_recvspace are the default send and receive window + * sizes, respectively. These are obsolescent (this information should + * be set by the route). + */ +u_long tcp_sendspace = 1024*16; +SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW, + &tcp_sendspace , 0, "Maximum outgoing TCP datagram size"); +u_long tcp_recvspace = 1024*16; +SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW, + &tcp_recvspace , 0, "Maximum incoming TCP datagram size"); + +/* + * Attach TCP protocol to socket, allocating + * internet protocol control block, tcp control block, + * bufer space, and entering LISTEN state if to accept connections. + */ +static int +tcp_attach(so, p) + struct socket *so; + struct proc *p; +{ + register struct tcpcb *tp; + struct inpcb *inp; + int error; +#ifdef INET6 + int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != NULL; +#endif + + 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, &tcbinfo, p); + if (error) + return (error); + inp = sotoinpcb(so); +#ifdef IPSEC + error = ipsec_init_policy(so, &inp->inp_sp); + if (error) { +#ifdef INET6 + if (isipv6) + in6_pcbdetach(inp); + else +#endif + in_pcbdetach(inp); + return (error); + } +#endif /*IPSEC*/ +#ifdef INET6 + if (isipv6) { + inp->inp_vflag |= INP_IPV6; + inp->in6p_hops = -1; /* use kernel default */ + } + else +#endif + inp->inp_vflag |= INP_IPV4; + 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 */ +#ifdef INET6 + if (isipv6) + in6_pcbdetach(inp); + else +#endif + 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). + */ +static 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. + */ +static struct tcpcb * +tcp_usrclosed(tp) + register struct tcpcb *tp; +{ + + switch (tp->t_state) { + + case TCPS_CLOSED: + case TCPS_LISTEN: + tp->t_state = TCPS_CLOSED; + tp = tcp_close(tp); + break; + + case TCPS_SYN_SENT: + case TCPS_SYN_RECEIVED: + tp->t_flags |= TF_NEEDFIN; + break; + + 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); + /* To prevent the connection hanging in FIN_WAIT_2 forever. */ + if (tp->t_state == TCPS_FIN_WAIT_2) + callout_reset(tp->tt_2msl, tcp_maxidle, + tcp_timer_2msl, tp); + } + return (tp); +} + |
