/*- * 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. * 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_inet.h" #include "opt_inet6.h" #include "opt_tcpdebug.h" #include #include #include #include #include #include #ifdef INET6 #include #endif /* INET6 */ #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #endif #include #ifdef INET6 #include #endif #include #include #ifdef INET6 #include #include #endif #include #include #include #include #include #include #ifdef TCPDEBUG #include #endif /* * TCP protocol interface to socket abstraction. */ extern char *tcpstates[]; /* XXX ??? */ static int tcp_attach(struct socket *); static int tcp_connect(struct tcpcb *, struct sockaddr *, struct thread *td); #ifdef INET6 static int tcp6_connect(struct tcpcb *, struct sockaddr *, struct thread *td); #endif /* INET6 */ static struct tcpcb * tcp_disconnect(struct tcpcb *); static struct tcpcb * tcp_usrclosed(struct tcpcb *); static void tcp_fill_info(struct tcpcb *, struct tcp_info *); #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 thread *td) { int error; struct inpcb *inp; struct tcpcb *tp = 0; TCPDEBUG0; INP_INFO_WLOCK(&tcbinfo); TCPDEBUG1(); inp = sotoinpcb(so); if (inp) { error = EISCONN; goto out; } error = tcp_attach(so); if (error) goto out; if ((so->so_options & SO_LINGER) && so->so_linger == 0) so->so_linger = TCP_LINGERTIME; inp = sotoinpcb(so); tp = intotcpcb(inp); out: TCPDEBUG2(PRU_ATTACH); INP_INFO_WUNLOCK(&tcbinfo); 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 error = 0; struct inpcb *inp; struct tcpcb *tp; TCPDEBUG0; INP_INFO_WLOCK(&tcbinfo); inp = sotoinpcb(so); if (inp == NULL) { INP_INFO_WUNLOCK(&tcbinfo); return error; } INP_LOCK(inp); tp = intotcpcb(inp); TCPDEBUG1(); tp = tcp_disconnect(tp); TCPDEBUG2(PRU_DETACH); if (tp) INP_UNLOCK(inp); INP_INFO_WUNLOCK(&tcbinfo); return error; } #define INI_NOLOCK 0 #define INI_READ 1 #define INI_WRITE 2 #define COMMON_START() \ TCPDEBUG0; \ do { \ if (inirw == INI_READ) \ INP_INFO_RLOCK(&tcbinfo); \ else if (inirw == INI_WRITE) \ INP_INFO_WLOCK(&tcbinfo); \ inp = sotoinpcb(so); \ if (inp == 0) { \ if (inirw == INI_READ) \ INP_INFO_RUNLOCK(&tcbinfo); \ else if (inirw == INI_WRITE) \ INP_INFO_WUNLOCK(&tcbinfo); \ return EINVAL; \ } \ INP_LOCK(inp); \ if (inirw == INI_READ) \ INP_INFO_RUNLOCK(&tcbinfo); \ tp = intotcpcb(inp); \ TCPDEBUG1(); \ } while(0) #define COMMON_END(req) \ out: TCPDEBUG2(req); \ do { \ if (tp) \ INP_UNLOCK(inp); \ if (inirw == INI_WRITE) \ INP_INFO_WUNLOCK(&tcbinfo); \ return error; \ goto out; \ } while(0) /* * Give the socket an address. */ static int tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in *sinp; const int inirw = INI_WRITE; sinp = (struct sockaddr_in *)nam; if (nam->sa_len != sizeof (*sinp)) return (EINVAL); /* * Must check for multicast addresses and disallow binding * to them. */ if (sinp->sin_family == AF_INET && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) return (EAFNOSUPPORT); COMMON_START(); error = in_pcbbind(inp, nam, td->td_ucred); if (error) goto out; COMMON_END(PRU_BIND); } #ifdef INET6 static int tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in6 *sin6p; const int inirw = INI_WRITE; sin6p = (struct sockaddr_in6 *)nam; if (nam->sa_len != sizeof (*sin6p)) return (EINVAL); /* * Must check for multicast addresses and disallow binding * to them. */ if (sin6p->sin6_family == AF_INET6 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) return (EAFNOSUPPORT); COMMON_START(); inp->inp_vflag &= ~INP_IPV4; inp->inp_vflag |= INP_IPV6; if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 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, td->td_ucred); goto out; } } error = in6_pcbbind(inp, nam, td->td_ucred); if (error) goto out; COMMON_END(PRU_BIND); } #endif /* INET6 */ /* * Prepare to accept connections. */ static int tcp_usr_listen(struct socket *so, int backlog, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_WRITE; COMMON_START(); SOCK_LOCK(so); error = solisten_proto_check(so); if (error == 0 && inp->inp_lport == 0) error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred); if (error == 0) { tp->t_state = TCPS_LISTEN; solisten_proto(so, backlog); } SOCK_UNLOCK(so); COMMON_END(PRU_LISTEN); } #ifdef INET6 static int tcp6_usr_listen(struct socket *so, int backlog, struct thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_WRITE; COMMON_START(); SOCK_LOCK(so); error = solisten_proto_check(so); if (error == 0 && inp->inp_lport == 0) { inp->inp_vflag &= ~INP_IPV4; if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) inp->inp_vflag |= INP_IPV4; error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred); } if (error == 0) { tp->t_state = TCPS_LISTEN; solisten_proto(so, backlog); } SOCK_UNLOCK(so); 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 thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in *sinp; const int inirw = INI_WRITE; sinp = (struct sockaddr_in *)nam; if (nam->sa_len != sizeof (*sinp)) return (EINVAL); /* * Must disallow TCP ``connections'' to multicast addresses. */ if (sinp->sin_family == AF_INET && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) return (EAFNOSUPPORT); if (jailed(td->td_ucred)) prison_remote_ip(td->td_ucred, 0, &sinp->sin_addr.s_addr); COMMON_START(); if ((error = tcp_connect(tp, nam, td)) != 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 thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; struct sockaddr_in6 *sin6p; const int inirw = INI_WRITE; sin6p = (struct sockaddr_in6 *)nam; if (nam->sa_len != sizeof (*sin6p)) return (EINVAL); /* * Must disallow TCP ``connections'' to multicast addresses. */ if (sin6p->sin6_family == AF_INET6 && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) return (EAFNOSUPPORT); COMMON_START(); if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) { struct sockaddr_in sin; if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) { error = EINVAL; goto out; } in6_sin6_2_sin(&sin, sin6p); inp->inp_vflag |= INP_IPV4; inp->inp_vflag &= ~INP_IPV6; if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0) goto out; error = tcp_output(tp); goto out; } inp->inp_vflag &= ~INP_IPV4; inp->inp_vflag |= INP_IPV6; inp->inp_inc.inc_isipv6 = 1; if ((error = tcp6_connect(tp, nam, td)) != 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 error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_WRITE; 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 error = 0; struct inpcb *inp = NULL; struct tcpcb *tp = NULL; struct in_addr addr; in_port_t port = 0; TCPDEBUG0; if (so->so_state & SS_ISDISCONNECTED) { error = ECONNABORTED; goto out; } INP_INFO_RLOCK(&tcbinfo); inp = sotoinpcb(so); if (!inp) { INP_INFO_RUNLOCK(&tcbinfo); return (EINVAL); } INP_LOCK(inp); INP_INFO_RUNLOCK(&tcbinfo); tp = intotcpcb(inp); TCPDEBUG1(); /* * We inline in_setpeeraddr and COMMON_END here, so that we can * copy the data of interest and defer the malloc until after we * release the lock. */ port = inp->inp_fport; addr = inp->inp_faddr; out: TCPDEBUG2(PRU_ACCEPT); if (tp) INP_UNLOCK(inp); if (error == 0) *nam = in_sockaddr(port, &addr); return error; } #ifdef INET6 static int tcp6_usr_accept(struct socket *so, struct sockaddr **nam) { struct inpcb *inp = NULL; int error = 0; struct tcpcb *tp = NULL; struct in_addr addr; struct in6_addr addr6; in_port_t port = 0; int v4 = 0; TCPDEBUG0; if (so->so_state & SS_ISDISCONNECTED) { error = ECONNABORTED; goto out; } INP_INFO_RLOCK(&tcbinfo); inp = sotoinpcb(so); if (inp == 0) { INP_INFO_RUNLOCK(&tcbinfo); return (EINVAL); } INP_LOCK(inp); INP_INFO_RUNLOCK(&tcbinfo); tp = intotcpcb(inp); TCPDEBUG1(); /* * We inline in6_mapped_peeraddr and COMMON_END here, so that we can * copy the data of interest and defer the malloc until after we * release the lock. */ if (inp->inp_vflag & INP_IPV4) { v4 = 1; port = inp->inp_fport; addr = inp->inp_faddr; } else { port = inp->inp_fport; addr6 = inp->in6p_faddr; } out: TCPDEBUG2(PRU_ACCEPT); if (tp) INP_UNLOCK(inp); if (error == 0) { if (v4) *nam = in6_v4mapsin6_sockaddr(port, &addr); else *nam = in6_sockaddr(port, &addr6); } return error; } #endif /* INET6 */ /* * This is the wrapper function for in_setsockaddr. We just pass down * the pcbinfo for in_setsockaddr to lock. We don't want to do the locking * here because in_setsockaddr will call malloc and can block. */ static int tcp_sockaddr(struct socket *so, struct sockaddr **nam) { return (in_setsockaddr(so, nam, &tcbinfo)); } /* * This is the wrapper function for in_setpeeraddr. We just pass down * the pcbinfo for in_setpeeraddr to lock. */ static int tcp_peeraddr(struct socket *so, struct sockaddr **nam) { return (in_setpeeraddr(so, nam, &tcbinfo)); } /* * Mark the connection as being incapable of further output. */ static int tcp_usr_shutdown(struct socket *so) { int error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_WRITE; 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 error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_READ; 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 thread *td) { int error = 0; struct inpcb *inp; struct tcpcb *tp; int unlocked = 0; #ifdef INET6 int isipv6; #endif TCPDEBUG0; /* * Need write lock here because this function might call * tcp_connect or tcp_usrclosed. * We really want to have to this function upgrade from read lock * to write lock. XXX */ INP_INFO_WLOCK(&tcbinfo); inp = sotoinpcb(so); if (inp == NULL) { /* * OOPS! we lost a race, the TCP session got reset after * we checked SBS_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; } INP_LOCK(inp); #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)) { sbappendstream(&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, td); else #endif /* INET6 */ error = tcp_connect(tp, nam, td); 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); } INP_INFO_WUNLOCK(&tcbinfo); unlocked = 1; 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 { SOCKBUF_LOCK(&so->so_snd); if (sbspace(&so->so_snd) < -512) { SOCKBUF_UNLOCK(&so->so_snd); 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. */ sbappendstream_locked(&so->so_snd, m); SOCKBUF_UNLOCK(&so->so_snd); 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, td); else #endif /* INET6 */ error = tcp_connect(tp, nam, td); if (error) goto out; tp->snd_wnd = TTCP_CLIENT_SND_WND; tcp_mss(tp, -1); } INP_INFO_WUNLOCK(&tcbinfo); unlocked = 1; tp->snd_up = tp->snd_una + so->so_snd.sb_cc; tp->t_flags |= TF_FORCEDATA; error = tcp_output(tp); tp->t_flags &= ~TF_FORCEDATA; } out: TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB : ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND)); if (tp) INP_UNLOCK(inp); if (!unlocked) INP_INFO_WUNLOCK(&tcbinfo); return (error); } /* * Abort the TCP. */ static void tcp_usr_abort(struct socket *so) { struct inpcb *inp; struct tcpcb *tp; TCPDEBUG0; INP_INFO_WLOCK(&tcbinfo); inp = sotoinpcb(so); if (inp == NULL) return; INP_LOCK(inp); tp = intotcpcb(inp); TCPDEBUG1(); tp = tcp_drop(tp, ECONNABORTED); TCPDEBUG2(PRU_ABORT); if (tp) INP_UNLOCK(inp); INP_INFO_WUNLOCK(&tcbinfo); } /* * Receive out-of-band data. */ static int tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags) { int error = 0; struct inpcb *inp; struct tcpcb *tp; const int inirw = INI_READ; COMMON_START(); if ((so->so_oobmark == 0 && (so->so_rcv.sb_state & SBS_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); } struct pr_usrreqs tcp_usrreqs = { .pru_abort = tcp_usr_abort, .pru_accept = tcp_usr_accept, .pru_attach = tcp_usr_attach, .pru_bind = tcp_usr_bind, .pru_connect = tcp_usr_connect, .pru_control = in_control, .pru_detach = tcp_usr_detach, .pru_disconnect = tcp_usr_disconnect, .pru_listen = tcp_usr_listen, .pru_peeraddr = tcp_peeraddr, .pru_rcvd = tcp_usr_rcvd, .pru_rcvoob = tcp_usr_rcvoob, .pru_send = tcp_usr_send, .pru_shutdown = tcp_usr_shutdown, .pru_sockaddr = tcp_sockaddr, .pru_sosetlabel = in_pcbsosetlabel }; #ifdef INET6 struct pr_usrreqs tcp6_usrreqs = { .pru_abort = tcp_usr_abort, .pru_accept = tcp6_usr_accept, .pru_attach = tcp_usr_attach, .pru_bind = tcp6_usr_bind, .pru_connect = tcp6_usr_connect, .pru_control = in6_control, .pru_detach = tcp_usr_detach, .pru_disconnect = tcp_usr_disconnect, .pru_listen = tcp6_usr_listen, .pru_peeraddr = in6_mapped_peeraddr, .pru_rcvd = tcp_usr_rcvd, .pru_rcvoob = tcp_usr_rcvoob, .pru_send = tcp_usr_send, .pru_shutdown = tcp_usr_shutdown, .pru_sockaddr = in6_mapped_sockaddr, .pru_sosetlabel = in_pcbsosetlabel }; #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_pcbconnect_setup 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, td) register struct tcpcb *tp; struct sockaddr *nam; struct thread *td; { struct inpcb *inp = tp->t_inpcb, *oinp; struct socket *so = inp->inp_socket; struct in_addr laddr; u_short lport; int error; if (inp->inp_lport == 0) { error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred); 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. */ laddr = inp->inp_laddr; lport = inp->inp_lport; error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport, &inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred); if (error && oinp == NULL) return error; if (oinp) return EADDRINUSE; inp->inp_laddr = laddr; in_pcbrehash(inp); /* 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_new_isn(tp); tp->t_bw_rtseq = tp->iss; tcp_sendseqinit(tp); return 0; } #ifdef INET6 static int tcp6_connect(tp, nam, td) register struct tcpcb *tp; struct sockaddr *nam; struct thread *td; { struct inpcb *inp = tp->t_inpcb, *oinp; struct socket *so = inp->inp_socket; struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam; struct in6_addr *addr6; int error; if (inp->inp_lport == 0) { error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred); 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. * in6_pcbladdr() also handles scope zone IDs. */ 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) 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; /* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */ inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK; if (inp->in6p_flags & IN6P_AUTOFLOWLABEL) inp->in6p_flowinfo |= (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); in_pcbrehash(inp); /* 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_new_isn(tp); tp->t_bw_rtseq = tp->iss; tcp_sendseqinit(tp); return 0; } #endif /* INET6 */ /* * Export TCP internal state information via a struct tcp_info, based on the * Linux 2.6 API. Not ABI compatible as our constants are mapped differently * (TCP state machine, etc). We export all information using FreeBSD-native * constants -- for example, the numeric values for tcpi_state will differ * from Linux. */ static void tcp_fill_info(tp, ti) struct tcpcb *tp; struct tcp_info *ti; { INP_LOCK_ASSERT(tp->t_inpcb); bzero(ti, sizeof(*ti)); ti->tcpi_state = tp->t_state; if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP)) ti->tcpi_options |= TCPI_OPT_TIMESTAMPS; if (tp->sack_enable) ti->tcpi_options |= TCPI_OPT_SACK; if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) { ti->tcpi_options |= TCPI_OPT_WSCALE; ti->tcpi_snd_wscale = tp->snd_scale; ti->tcpi_rcv_wscale = tp->rcv_scale; } ti->tcpi_snd_ssthresh = tp->snd_ssthresh; ti->tcpi_snd_cwnd = tp->snd_cwnd; /* * FreeBSD-specific extension fields for tcp_info. */ ti->tcpi_rcv_space = tp->rcv_wnd; ti->tcpi_snd_wnd = tp->snd_wnd; ti->tcpi_snd_bwnd = tp->snd_bwnd; } /* * 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.) * * XXXRW: The locking here is wrong; we may take a page fault while holding * the inpcb lock. */ int tcp_ctloutput(so, sopt) struct socket *so; struct sockopt *sopt; { int error, opt, optval; struct inpcb *inp; struct tcpcb *tp; struct tcp_info ti; error = 0; INP_INFO_RLOCK(&tcbinfo); inp = sotoinpcb(so); if (inp == NULL) { INP_INFO_RUNLOCK(&tcbinfo); return (ECONNRESET); } INP_LOCK(inp); INP_INFO_RUNLOCK(&tcbinfo); if (sopt->sopt_level != IPPROTO_TCP) { INP_UNLOCK(inp); #ifdef INET6 if (INP_CHECK_SOCKAF(so, AF_INET6)) error = ip6_ctloutput(so, sopt); else #endif /* INET6 */ error = ip_ctloutput(so, sopt); return (error); } tp = intotcpcb(inp); switch (sopt->sopt_dir) { case SOPT_SET: switch (sopt->sopt_name) { #ifdef TCP_SIGNATURE case TCP_MD5SIG: error = sooptcopyin(sopt, &optval, sizeof optval, sizeof optval); if (error) break; if (optval > 0) tp->t_flags |= TF_SIGNATURE; else tp->t_flags &= ~TF_SIGNATURE; break; #endif /* TCP_SIGNATURE */ 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 && optval + 40 >= tcp_minmss) tp->t_maxseg = optval; else error = EINVAL; break; case TCP_INFO: error = EINVAL; break; default: error = ENOPROTOOPT; break; } break; case SOPT_GET: switch (sopt->sopt_name) { #ifdef TCP_SIGNATURE case TCP_MD5SIG: optval = (tp->t_flags & TF_SIGNATURE) ? 1 : 0; error = sooptcopyout(sopt, &optval, sizeof optval); break; #endif case TCP_NODELAY: optval = tp->t_flags & TF_NODELAY; error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_MAXSEG: optval = tp->t_maxseg; error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_NOOPT: optval = tp->t_flags & TF_NOOPT; error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_NOPUSH: optval = tp->t_flags & TF_NOPUSH; error = sooptcopyout(sopt, &optval, sizeof optval); break; case TCP_INFO: tcp_fill_info(tp, &ti); error = sooptcopyout(sopt, &ti, sizeof ti); break; default: error = ENOPROTOOPT; break; } break; } INP_UNLOCK(inp); 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*32; SYSCTL_ULONG(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW, &tcp_sendspace , 0, "Maximum outgoing TCP datagram size"); u_long tcp_recvspace = 1024*64; SYSCTL_ULONG(_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) struct socket *so; { register struct tcpcb *tp; struct inpcb *inp; int error; #ifdef INET6 int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != 0; #endif INP_INFO_WLOCK_ASSERT(&tcbinfo); 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, "tcpinp"); if (error) return (error); inp = sotoinpcb(so); #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 */ INP_LOCK(inp); #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 inpcb *inp = tp->t_inpcb; struct socket *so = inp->inp_socket; INP_INFO_WLOCK_ASSERT(&tcbinfo); INP_LOCK_ASSERT(inp); 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; { INP_INFO_WLOCK_ASSERT(&tcbinfo); INP_LOCK_ASSERT(tp->t_inpcb); 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); }