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-rw-r--r--slirp/tcp_subr.c1325
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diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c
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+/*
+ * Copyright (c) 1982, 1986, 1988, 1990, 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_subr.c 8.1 (Berkeley) 6/10/93
+ * tcp_subr.c,v 1.5 1994/10/08 22:39:58 phk Exp
+ */
+
+/*
+ * Changes and additions relating to SLiRP
+ * Copyright (c) 1995 Danny Gasparovski.
+ *
+ * Please read the file COPYRIGHT for the
+ * terms and conditions of the copyright.
+ */
+
+#define WANT_SYS_IOCTL_H
+#include <slirp.h>
+
+/* patchable/settable parameters for tcp */
+int tcp_mssdflt = TCP_MSS;
+int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ;
+int tcp_do_rfc1323 = 0; /* Don't do rfc1323 performance enhancements */
+int tcp_rcvspace; /* You may want to change this */
+int tcp_sndspace; /* Keep small if you have an error prone link */
+
+/*
+ * Tcp initialization
+ */
+void
+tcp_init()
+{
+ tcp_iss = 1; /* wrong */
+ tcb.so_next = tcb.so_prev = &tcb;
+
+ /* tcp_rcvspace = our Window we advertise to the remote */
+ tcp_rcvspace = TCP_RCVSPACE;
+ tcp_sndspace = TCP_SNDSPACE;
+
+ /* Make sure tcp_sndspace is at least 2*MSS */
+ if (tcp_sndspace < 2*(min(if_mtu, if_mru) - sizeof(struct tcpiphdr)))
+ tcp_sndspace = 2*(min(if_mtu, if_mru) - sizeof(struct tcpiphdr));
+}
+
+/*
+ * Create template to be used to send tcp packets on a connection.
+ * Call after host entry created, fills
+ * in a skeletal tcp/ip header, minimizing the amount of work
+ * necessary when the connection is used.
+ */
+/* struct tcpiphdr * */
+void
+tcp_template(tp)
+ struct tcpcb *tp;
+{
+ struct socket *so = tp->t_socket;
+ register struct tcpiphdr *n = &tp->t_template;
+
+ n->ti_next = n->ti_prev = 0;
+ n->ti_x1 = 0;
+ n->ti_pr = IPPROTO_TCP;
+ n->ti_len = htons(sizeof (struct tcpiphdr) - sizeof (struct ip));
+ n->ti_src = so->so_faddr;
+ n->ti_dst = so->so_laddr;
+ n->ti_sport = so->so_fport;
+ n->ti_dport = so->so_lport;
+
+ n->ti_seq = 0;
+ n->ti_ack = 0;
+ n->ti_x2 = 0;
+ n->ti_off = 5;
+ n->ti_flags = 0;
+ n->ti_win = 0;
+ n->ti_sum = 0;
+ n->ti_urp = 0;
+}
+
+/*
+ * Send a single message to the TCP at address specified by
+ * the given TCP/IP header. If m == 0, then we make a copy
+ * of the tcpiphdr at ti and send directly to the addressed host.
+ * This is used to force keep alive messages out using the TCP
+ * template for a connection tp->t_template. If flags are given
+ * then we send a message back to the TCP which originated the
+ * segment ti, and discard the mbuf containing it and any other
+ * attached mbufs.
+ *
+ * In any case the ack and sequence number of the transmitted
+ * segment are as specified by the parameters.
+ */
+void
+tcp_respond(tp, ti, m, ack, seq, flags)
+ struct tcpcb *tp;
+ register struct tcpiphdr *ti;
+ register struct mbuf *m;
+ tcp_seq ack, seq;
+ int flags;
+{
+ register int tlen;
+ int win = 0;
+
+ DEBUG_CALL("tcp_respond");
+ DEBUG_ARG("tp = %lx", (long)tp);
+ DEBUG_ARG("ti = %lx", (long)ti);
+ DEBUG_ARG("m = %lx", (long)m);
+ DEBUG_ARG("ack = %u", ack);
+ DEBUG_ARG("seq = %u", seq);
+ DEBUG_ARG("flags = %x", flags);
+
+ if (tp)
+ win = sbspace(&tp->t_socket->so_rcv);
+ if (m == 0) {
+ if ((m = m_get()) == NULL)
+ return;
+#ifdef TCP_COMPAT_42
+ tlen = 1;
+#else
+ tlen = 0;
+#endif
+ m->m_data += if_maxlinkhdr;
+ *mtod(m, struct tcpiphdr *) = *ti;
+ ti = mtod(m, struct tcpiphdr *);
+ flags = TH_ACK;
+ } else {
+ /*
+ * ti points into m so the next line is just making
+ * the mbuf point to ti
+ */
+ m->m_data = (caddr_t)ti;
+
+ m->m_len = sizeof (struct tcpiphdr);
+ tlen = 0;
+#define xchg(a,b,type) { type t; t=a; a=b; b=t; }
+ xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, u_int32_t);
+ xchg(ti->ti_dport, ti->ti_sport, u_int16_t);
+#undef xchg
+ }
+ ti->ti_len = htons((u_short)(sizeof (struct tcphdr) + tlen));
+ tlen += sizeof (struct tcpiphdr);
+ m->m_len = tlen;
+
+ ti->ti_next = ti->ti_prev = 0;
+ ti->ti_x1 = 0;
+ ti->ti_seq = htonl(seq);
+ ti->ti_ack = htonl(ack);
+ ti->ti_x2 = 0;
+ ti->ti_off = sizeof (struct tcphdr) >> 2;
+ ti->ti_flags = flags;
+ if (tp)
+ ti->ti_win = htons((u_int16_t) (win >> tp->rcv_scale));
+ else
+ ti->ti_win = htons((u_int16_t)win);
+ ti->ti_urp = 0;
+ ti->ti_sum = 0;
+ ti->ti_sum = cksum(m, tlen);
+ ((struct ip *)ti)->ip_len = tlen;
+
+ if(flags & TH_RST)
+ ((struct ip *)ti)->ip_ttl = MAXTTL;
+ else
+ ((struct ip *)ti)->ip_ttl = ip_defttl;
+
+ (void) ip_output((struct socket *)0, m);
+}
+
+/*
+ * Create a new TCP control block, making an
+ * empty reassembly queue and hooking it to the argument
+ * protocol control block.
+ */
+struct tcpcb *
+tcp_newtcpcb(so)
+ struct socket *so;
+{
+ register struct tcpcb *tp;
+
+ tp = (struct tcpcb *)malloc(sizeof(*tp));
+ if (tp == NULL)
+ return ((struct tcpcb *)0);
+
+ memset((char *) tp, 0, sizeof(struct tcpcb));
+ tp->seg_next = tp->seg_prev = (tcpiphdrp_32)tp;
+ tp->t_maxseg = tcp_mssdflt;
+
+ tp->t_flags = tcp_do_rfc1323 ? (TF_REQ_SCALE|TF_REQ_TSTMP) : 0;
+ tp->t_socket = so;
+
+ /*
+ * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
+ * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives
+ * reasonable initial retransmit time.
+ */
+ tp->t_srtt = TCPTV_SRTTBASE;
+ tp->t_rttvar = tcp_rttdflt * PR_SLOWHZ << 2;
+ tp->t_rttmin = TCPTV_MIN;
+
+ TCPT_RANGESET(tp->t_rxtcur,
+ ((TCPTV_SRTTBASE >> 2) + (TCPTV_SRTTDFLT << 2)) >> 1,
+ TCPTV_MIN, TCPTV_REXMTMAX);
+
+ tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
+ tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
+ tp->t_state = TCPS_CLOSED;
+
+ so->so_tcpcb = tp;
+
+ return (tp);
+}
+
+/*
+ * Drop a TCP connection, reporting
+ * the specified error. If connection is synchronized,
+ * then send a RST to peer.
+ */
+struct tcpcb *tcp_drop(struct tcpcb *tp, int errno)
+{
+/* tcp_drop(tp, errno)
+ register struct tcpcb *tp;
+ int errno;
+{
+*/
+
+ DEBUG_CALL("tcp_drop");
+ DEBUG_ARG("tp = %lx", (long)tp);
+ DEBUG_ARG("errno = %d", errno);
+
+ if (TCPS_HAVERCVDSYN(tp->t_state)) {
+ tp->t_state = TCPS_CLOSED;
+ (void) tcp_output(tp);
+ tcpstat.tcps_drops++;
+ } else
+ tcpstat.tcps_conndrops++;
+/* if (errno == ETIMEDOUT && tp->t_softerror)
+ * errno = tp->t_softerror;
+ */
+/* so->so_error = errno; */
+ return (tcp_close(tp));
+}
+
+/*
+ * Close a TCP control block:
+ * discard all space held by the tcp
+ * discard internet protocol block
+ * wake up any sleepers
+ */
+struct tcpcb *
+tcp_close(tp)
+ register struct tcpcb *tp;
+{
+ register struct tcpiphdr *t;
+ struct socket *so = tp->t_socket;
+ register struct mbuf *m;
+
+ DEBUG_CALL("tcp_close");
+ DEBUG_ARG("tp = %lx", (long )tp);
+
+ /* free the reassembly queue, if any */
+ t = (struct tcpiphdr *) tp->seg_next;
+ while (t != (struct tcpiphdr *)tp) {
+ t = (struct tcpiphdr *)t->ti_next;
+ m = (struct mbuf *) REASS_MBUF((struct tcpiphdr *)t->ti_prev);
+ remque_32((struct tcpiphdr *) t->ti_prev);
+ m_freem(m);
+ }
+ /* It's static */
+/* if (tp->t_template)
+ * (void) m_free(dtom(tp->t_template));
+ */
+/* free(tp, M_PCB); */
+ free(tp);
+ so->so_tcpcb = 0;
+ soisfdisconnected(so);
+ /* clobber input socket cache if we're closing the cached connection */
+ if (so == tcp_last_so)
+ tcp_last_so = &tcb;
+ close(so->s);
+ sbfree(&so->so_rcv);
+ sbfree(&so->so_snd);
+ sofree(so);
+ tcpstat.tcps_closed++;
+ return ((struct tcpcb *)0);
+}
+
+void
+tcp_drain()
+{
+ /* XXX */
+}
+
+/*
+ * When a source quench is received, close congestion window
+ * to one segment. We will gradually open it again as we proceed.
+ */
+
+#ifdef notdef
+
+void
+tcp_quench(i, errno)
+
+ int errno;
+{
+ struct tcpcb *tp = intotcpcb(inp);
+
+ if (tp)
+ tp->snd_cwnd = tp->t_maxseg;
+}
+
+#endif /* notdef */
+
+/*
+ * TCP protocol interface to socket abstraction.
+ */
+
+/*
+ * 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.
+ */
+void
+tcp_sockclosed(tp)
+ struct tcpcb *tp;
+{
+
+ DEBUG_CALL("tcp_sockclosed");
+ DEBUG_ARG("tp = %lx", (long)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;
+ }
+/* soisfdisconnecting(tp->t_socket); */
+ if (tp && tp->t_state >= TCPS_FIN_WAIT_2)
+ soisfdisconnected(tp->t_socket);
+ if (tp)
+ tcp_output(tp);
+}
+
+/*
+ * Connect to a host on the Internet
+ * Called by tcp_input
+ * Only do a connect, the tcp fields will be set in tcp_input
+ * return 0 if there's a result of the connect,
+ * else return -1 means we're still connecting
+ * The return value is almost always -1 since the socket is
+ * nonblocking. Connect returns after the SYN is sent, and does
+ * not wait for ACK+SYN.
+ */
+int tcp_fconnect(so)
+ struct socket *so;
+{
+ int ret=0;
+
+ DEBUG_CALL("tcp_fconnect");
+ DEBUG_ARG("so = %lx", (long )so);
+
+ if( (ret=so->s=socket(AF_INET,SOCK_STREAM,0)) >= 0) {
+ int opt, s=so->s;
+ struct sockaddr_in addr;
+
+ fd_nonblock(s);
+ opt = 1;
+ setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(opt ));
+ opt = 1;
+ setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(opt ));
+
+ addr.sin_family = AF_INET;
+ if ((so->so_faddr.s_addr & htonl(0xffffff00)) == special_addr.s_addr) {
+ /* It's an alias */
+ switch(ntohl(so->so_faddr.s_addr) & 0xff) {
+ case CTL_DNS:
+ addr.sin_addr = dns_addr;
+ break;
+ case CTL_ALIAS:
+ default:
+ addr.sin_addr = loopback_addr;
+ break;
+ }
+ } else
+ addr.sin_addr = so->so_faddr;
+ addr.sin_port = so->so_fport;
+
+ DEBUG_MISC((dfd, " connect()ing, addr.sin_port=%d, "
+ "addr.sin_addr.s_addr=%.16s\n",
+ ntohs(addr.sin_port), inet_ntoa(addr.sin_addr)));
+ /* We don't care what port we get */
+ ret = connect(s,(struct sockaddr *)&addr,sizeof (addr));
+
+ /*
+ * If it's not in progress, it failed, so we just return 0,
+ * without clearing SS_NOFDREF
+ */
+ soisfconnecting(so);
+ }
+
+ return(ret);
+}
+
+/*
+ * Accept the socket and connect to the local-host
+ *
+ * We have a problem. The correct thing to do would be
+ * to first connect to the local-host, and only if the
+ * connection is accepted, then do an accept() here.
+ * But, a) we need to know who's trying to connect
+ * to the socket to be able to SYN the local-host, and
+ * b) we are already connected to the foreign host by
+ * the time it gets to accept(), so... We simply accept
+ * here and SYN the local-host.
+ */
+void
+tcp_connect(inso)
+ struct socket *inso;
+{
+ struct socket *so;
+ struct sockaddr_in addr;
+ int addrlen = sizeof(struct sockaddr_in);
+ struct tcpcb *tp;
+ int s, opt;
+
+ DEBUG_CALL("tcp_connect");
+ DEBUG_ARG("inso = %lx", (long)inso);
+
+ /*
+ * If it's an SS_ACCEPTONCE socket, no need to socreate()
+ * another socket, just use the accept() socket.
+ */
+ if (inso->so_state & SS_FACCEPTONCE) {
+ /* FACCEPTONCE already have a tcpcb */
+ so = inso;
+ } else {
+ if ((so = socreate()) == NULL) {
+ /* If it failed, get rid of the pending connection */
+ close(accept(inso->s,(struct sockaddr *)&addr,&addrlen));
+ return;
+ }
+ if (tcp_attach(so) < 0) {
+ free(so); /* NOT sofree */
+ return;
+ }
+ so->so_laddr = inso->so_laddr;
+ so->so_lport = inso->so_lport;
+ }
+
+ (void) tcp_mss(sototcpcb(so), 0);
+
+ if ((s = accept(inso->s,(struct sockaddr *)&addr,&addrlen)) < 0) {
+ tcp_close(sototcpcb(so)); /* This will sofree() as well */
+ return;
+ }
+ fd_nonblock(s);
+ opt = 1;
+ setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
+ opt = 1;
+ setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
+
+ so->so_fport = addr.sin_port;
+ so->so_faddr = addr.sin_addr;
+ /* Translate connections from localhost to the real hostname */
+ if (so->so_faddr.s_addr == 0 || so->so_faddr.s_addr == loopback_addr.s_addr)
+ so->so_faddr = our_addr;
+
+ /* Close the accept() socket, set right state */
+ if (inso->so_state & SS_FACCEPTONCE) {
+ close(so->s); /* If we only accept once, close the accept() socket */
+ so->so_state = SS_NOFDREF; /* Don't select it yet, even though we have an FD */
+ /* if it's not FACCEPTONCE, it's already NOFDREF */
+ }
+ so->s = s;
+
+ so->so_iptos = tcp_tos(so);
+ tp = sototcpcb(so);
+
+ tcp_template(tp);
+
+ /* 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); */ /* NOFDREF used instead */
+ 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);
+ tcp_output(tp);
+}
+
+/*
+ * Attach a TCPCB to a socket.
+ */
+int
+tcp_attach(so)
+ struct socket *so;
+{
+ if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL)
+ return -1;
+
+ insque(so, &tcb);
+
+ return 0;
+}
+
+/*
+ * Set the socket's type of service field
+ */
+struct tos_t tcptos[] = {
+ {0, 20, IPTOS_THROUGHPUT, 0}, /* ftp data */
+ {21, 21, IPTOS_LOWDELAY, EMU_FTP}, /* ftp control */
+ {0, 23, IPTOS_LOWDELAY, 0}, /* telnet */
+ {0, 80, IPTOS_THROUGHPUT, 0}, /* WWW */
+ {0, 513, IPTOS_LOWDELAY, EMU_RLOGIN|EMU_NOCONNECT}, /* rlogin */
+ {0, 514, IPTOS_LOWDELAY, EMU_RSH|EMU_NOCONNECT}, /* shell */
+ {0, 544, IPTOS_LOWDELAY, EMU_KSH}, /* kshell */
+ {0, 543, IPTOS_LOWDELAY, 0}, /* klogin */
+ {0, 6667, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC */
+ {0, 6668, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC undernet */
+ {0, 7070, IPTOS_LOWDELAY, EMU_REALAUDIO }, /* RealAudio control */
+ {0, 113, IPTOS_LOWDELAY, EMU_IDENT }, /* identd protocol */
+ {0, 0, 0, 0}
+};
+
+struct emu_t *tcpemu = 0;
+
+/*
+ * Return TOS according to the above table
+ */
+u_int8_t
+tcp_tos(so)
+ struct socket *so;
+{
+ int i = 0;
+ struct emu_t *emup;
+
+ while(tcptos[i].tos) {
+ if ((tcptos[i].fport && (ntohs(so->so_fport) == tcptos[i].fport)) ||
+ (tcptos[i].lport && (ntohs(so->so_lport) == tcptos[i].lport))) {
+ so->so_emu = tcptos[i].emu;
+ return tcptos[i].tos;
+ }
+ i++;
+ }
+
+ /* Nope, lets see if there's a user-added one */
+ for (emup = tcpemu; emup; emup = emup->next) {
+ if ((emup->fport && (ntohs(so->so_fport) == emup->fport)) ||
+ (emup->lport && (ntohs(so->so_lport) == emup->lport))) {
+ so->so_emu = emup->emu;
+ return emup->tos;
+ }
+ }
+
+ return 0;
+}
+
+int do_echo = -1;
+
+/*
+ * Emulate programs that try and connect to us
+ * This includes ftp (the data connection is
+ * initiated by the server) and IRC (DCC CHAT and
+ * DCC SEND) for now
+ *
+ * NOTE: It's possible to crash SLiRP by sending it
+ * unstandard strings to emulate... if this is a problem,
+ * more checks are needed here
+ *
+ * XXX Assumes the whole command came in one packet
+ *
+ * XXX Some ftp clients will have their TOS set to
+ * LOWDELAY and so Nagel will kick in. Because of this,
+ * we'll get the first letter, followed by the rest, so
+ * we simply scan for ORT instead of PORT...
+ * DCC doesn't have this problem because there's other stuff
+ * in the packet before the DCC command.
+ *
+ * Return 1 if the mbuf m is still valid and should be
+ * sbappend()ed
+ *
+ * NOTE: if you return 0 you MUST m_free() the mbuf!
+ */
+int
+tcp_emu(so, m)
+ struct socket *so;
+ struct mbuf *m;
+{
+ u_int n1, n2, n3, n4, n5, n6;
+ char buff[256];
+ u_int32_t laddr;
+ u_int lport;
+ char *bptr;
+
+ DEBUG_CALL("tcp_emu");
+ DEBUG_ARG("so = %lx", (long)so);
+ DEBUG_ARG("m = %lx", (long)m);
+
+ switch(so->so_emu) {
+ int x, i;
+
+ case EMU_IDENT:
+ /*
+ * Identification protocol as per rfc-1413
+ */
+
+ {
+ struct socket *tmpso;
+ struct sockaddr_in addr;
+ int addrlen = sizeof(struct sockaddr_in);
+ struct sbuf *so_rcv = &so->so_rcv;
+
+ memcpy(so_rcv->sb_wptr, m->m_data, m->m_len);
+ so_rcv->sb_wptr += m->m_len;
+ so_rcv->sb_rptr += m->m_len;
+ m->m_data[m->m_len] = 0; /* NULL terminate */
+ if (strchr(m->m_data, '\r') || strchr(m->m_data, '\n')) {
+ if (sscanf(so_rcv->sb_data, "%d%*[ ,]%d", &n1, &n2) == 2) {
+ HTONS(n1);
+ HTONS(n2);
+ /* n2 is the one on our host */
+ for (tmpso = tcb.so_next; tmpso != &tcb; tmpso = tmpso->so_next) {
+ if (tmpso->so_laddr.s_addr == so->so_laddr.s_addr &&
+ tmpso->so_lport == n2 &&
+ tmpso->so_faddr.s_addr == so->so_faddr.s_addr &&
+ tmpso->so_fport == n1) {
+ if (getsockname(tmpso->s,
+ (struct sockaddr *)&addr, &addrlen) == 0)
+ n2 = ntohs(addr.sin_port);
+ break;
+ }
+ }
+ }
+ so_rcv->sb_cc = sprintf(so_rcv->sb_data, "%d,%d\r\n", n1, n2);
+ so_rcv->sb_rptr = so_rcv->sb_data;
+ so_rcv->sb_wptr = so_rcv->sb_data + so_rcv->sb_cc;
+ }
+ m_free(m);
+ return 0;
+ }
+
+#if 0
+ case EMU_RLOGIN:
+ /*
+ * Rlogin emulation
+ * First we accumulate all the initial option negotiation,
+ * then fork_exec() rlogin according to the options
+ */
+ {
+ int i, i2, n;
+ char *ptr;
+ char args[100];
+ char term[100];
+ struct sbuf *so_snd = &so->so_snd;
+ struct sbuf *so_rcv = &so->so_rcv;
+
+ /* First check if they have a priveladged port, or too much data has arrived */
+ if (ntohs(so->so_lport) > 1023 || ntohs(so->so_lport) < 512 ||
+ (m->m_len + so_rcv->sb_wptr) > (so_rcv->sb_data + so_rcv->sb_datalen)) {
+ memcpy(so_snd->sb_wptr, "Permission denied\n", 18);
+ so_snd->sb_wptr += 18;
+ so_snd->sb_cc += 18;
+ tcp_sockclosed(sototcpcb(so));
+ m_free(m);
+ return 0;
+ }
+
+ /* Append the current data */
+ memcpy(so_rcv->sb_wptr, m->m_data, m->m_len);
+ so_rcv->sb_wptr += m->m_len;
+ so_rcv->sb_rptr += m->m_len;
+ m_free(m);
+
+ /*
+ * Check if we have all the initial options,
+ * and build argument list to rlogin while we're here
+ */
+ n = 0;
+ ptr = so_rcv->sb_data;
+ args[0] = 0;
+ term[0] = 0;
+ while (ptr < so_rcv->sb_wptr) {
+ if (*ptr++ == 0) {
+ n++;
+ if (n == 2) {
+ sprintf(args, "rlogin -l %s %s",
+ ptr, inet_ntoa(so->so_faddr));
+ } else if (n == 3) {
+ i2 = so_rcv->sb_wptr - ptr;
+ for (i = 0; i < i2; i++) {
+ if (ptr[i] == '/') {
+ ptr[i] = 0;
+#ifdef HAVE_SETENV
+ sprintf(term, "%s", ptr);
+#else
+ sprintf(term, "TERM=%s", ptr);
+#endif
+ ptr[i] = '/';
+ break;
+ }
+ }
+ }
+ }
+ }
+
+ if (n != 4)
+ return 0;
+
+ /* We have it, set our term variable and fork_exec() */
+#ifdef HAVE_SETENV
+ setenv("TERM", term, 1);
+#else
+ putenv(term);
+#endif
+ fork_exec(so, args, 2);
+ term[0] = 0;
+ so->so_emu = 0;
+
+ /* And finally, send the client a 0 character */
+ so_snd->sb_wptr[0] = 0;
+ so_snd->sb_wptr++;
+ so_snd->sb_cc++;
+
+ return 0;
+ }
+
+ case EMU_RSH:
+ /*
+ * rsh emulation
+ * First we accumulate all the initial option negotiation,
+ * then rsh_exec() rsh according to the options
+ */
+ {
+ int n;
+ char *ptr;
+ char *user;
+ char *args;
+ struct sbuf *so_snd = &so->so_snd;
+ struct sbuf *so_rcv = &so->so_rcv;
+
+ /* First check if they have a priveladged port, or too much data has arrived */
+ if (ntohs(so->so_lport) > 1023 || ntohs(so->so_lport) < 512 ||
+ (m->m_len + so_rcv->sb_wptr) > (so_rcv->sb_data + so_rcv->sb_datalen)) {
+ memcpy(so_snd->sb_wptr, "Permission denied\n", 18);
+ so_snd->sb_wptr += 18;
+ so_snd->sb_cc += 18;
+ tcp_sockclosed(sototcpcb(so));
+ m_free(m);
+ return 0;
+ }
+
+ /* Append the current data */
+ memcpy(so_rcv->sb_wptr, m->m_data, m->m_len);
+ so_rcv->sb_wptr += m->m_len;
+ so_rcv->sb_rptr += m->m_len;
+ m_free(m);
+
+ /*
+ * Check if we have all the initial options,
+ * and build argument list to rlogin while we're here
+ */
+ n = 0;
+ ptr = so_rcv->sb_data;
+ user="";
+ args="";
+ if (so->extra==NULL) {
+ struct socket *ns;
+ struct tcpcb* tp;
+ int port=atoi(ptr);
+ if (port <= 0) return 0;
+ if (port > 1023 || port < 512) {
+ memcpy(so_snd->sb_wptr, "Permission denied\n", 18);
+ so_snd->sb_wptr += 18;
+ so_snd->sb_cc += 18;
+ tcp_sockclosed(sototcpcb(so));
+ return 0;
+ }
+ if ((ns=socreate()) == NULL)
+ return 0;
+ if (tcp_attach(ns)<0) {
+ free(ns);
+ return 0;
+ }
+
+ ns->so_laddr=so->so_laddr;
+ ns->so_lport=htons(port);
+
+ (void) tcp_mss(sototcpcb(ns), 0);
+
+ ns->so_faddr=so->so_faddr;
+ ns->so_fport=htons(IPPORT_RESERVED-1); /* Use a fake port. */
+
+ if (ns->so_faddr.s_addr == 0 ||
+ ns->so_faddr.s_addr == loopback_addr.s_addr)
+ ns->so_faddr = our_addr;
+
+ ns->so_iptos = tcp_tos(ns);
+ tp = sototcpcb(ns);
+
+ tcp_template(tp);
+
+ /* 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++;
+ */
+
+ /*soisfconnecting(ns);*/
+
+ 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);
+ tcp_output(tp);
+ so->extra=ns;
+ }
+ while (ptr < so_rcv->sb_wptr) {
+ if (*ptr++ == 0) {
+ n++;
+ if (n == 2) {
+ user=ptr;
+ } else if (n == 3) {
+ args=ptr;
+ }
+ }
+ }
+
+ if (n != 4)
+ return 0;
+
+ rsh_exec(so,so->extra, user, inet_ntoa(so->so_faddr), args);
+ so->so_emu = 0;
+ so->extra=NULL;
+
+ /* And finally, send the client a 0 character */
+ so_snd->sb_wptr[0] = 0;
+ so_snd->sb_wptr++;
+ so_snd->sb_cc++;
+
+ return 0;
+ }
+
+ case EMU_CTL:
+ {
+ int num;
+ struct sbuf *so_snd = &so->so_snd;
+ struct sbuf *so_rcv = &so->so_rcv;
+
+ /*
+ * If there is binary data here, we save it in so->so_m
+ */
+ if (!so->so_m) {
+ int rxlen;
+ char *rxdata;
+ rxdata=mtod(m, char *);
+ for (rxlen=m->m_len; rxlen; rxlen--) {
+ if (*rxdata++ & 0x80) {
+ so->so_m = m;
+ return 0;
+ }
+ }
+ } /* if(so->so_m==NULL) */
+
+ /*
+ * Append the line
+ */
+ sbappendsb(so_rcv, m);
+
+ /* To avoid going over the edge of the buffer, we reset it */
+ if (so_snd->sb_cc == 0)
+ so_snd->sb_wptr = so_snd->sb_rptr = so_snd->sb_data;
+
+ /*
+ * A bit of a hack:
+ * If the first packet we get here is 1 byte long, then it
+ * was done in telnet character mode, therefore we must echo
+ * the characters as they come. Otherwise, we echo nothing,
+ * because in linemode, the line is already echoed
+ * XXX two or more control connections won't work
+ */
+ if (do_echo == -1) {
+ if (m->m_len == 1) do_echo = 1;
+ else do_echo = 0;
+ }
+ if (do_echo) {
+ sbappendsb(so_snd, m);
+ m_free(m);
+ tcp_output(sototcpcb(so)); /* XXX */
+ } else
+ m_free(m);
+
+ num = 0;
+ while (num < so->so_rcv.sb_cc) {
+ if (*(so->so_rcv.sb_rptr + num) == '\n' ||
+ *(so->so_rcv.sb_rptr + num) == '\r') {
+ int n;
+
+ *(so_rcv->sb_rptr + num) = 0;
+ if (ctl_password && !ctl_password_ok) {
+ /* Need a password */
+ if (sscanf(so_rcv->sb_rptr, "pass %256s", buff) == 1) {
+ if (strcmp(buff, ctl_password) == 0) {
+ ctl_password_ok = 1;
+ n = sprintf(so_snd->sb_wptr,
+ "Password OK.\r\n");
+ goto do_prompt;
+ }
+ }
+ n = sprintf(so_snd->sb_wptr,
+ "Error: Password required, log on with \"pass PASSWORD\"\r\n");
+ goto do_prompt;
+ }
+ cfg_quitting = 0;
+ n = do_config(so_rcv->sb_rptr, so, PRN_SPRINTF);
+ if (!cfg_quitting) {
+ /* Register the printed data */
+do_prompt:
+ so_snd->sb_cc += n;
+ so_snd->sb_wptr += n;
+ /* Add prompt */
+ n = sprintf(so_snd->sb_wptr, "Slirp> ");
+ so_snd->sb_cc += n;
+ so_snd->sb_wptr += n;
+ }
+ /* Drop so_rcv data */
+ so_rcv->sb_cc = 0;
+ so_rcv->sb_wptr = so_rcv->sb_rptr = so_rcv->sb_data;
+ tcp_output(sototcpcb(so)); /* Send the reply */
+ }
+ num++;
+ }
+ return 0;
+ }
+#endif
+ case EMU_FTP: /* ftp */
+ *(m->m_data+m->m_len) = 0; /* NULL terminate for strstr */
+ if ((bptr = (char *)strstr(m->m_data, "ORT")) != NULL) {
+ /*
+ * Need to emulate the PORT command
+ */
+ x = sscanf(bptr, "ORT %d,%d,%d,%d,%d,%d\r\n%256[^\177]",
+ &n1, &n2, &n3, &n4, &n5, &n6, buff);
+ if (x < 6)
+ return 1;
+
+ laddr = htonl((n1 << 24) | (n2 << 16) | (n3 << 8) | (n4));
+ lport = htons((n5 << 8) | (n6));
+
+ if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL)
+ return 1;
+
+ n6 = ntohs(so->so_fport);
+
+ n5 = (n6 >> 8) & 0xff;
+ n6 &= 0xff;
+
+ laddr = ntohl(so->so_faddr.s_addr);
+
+ n1 = ((laddr >> 24) & 0xff);
+ n2 = ((laddr >> 16) & 0xff);
+ n3 = ((laddr >> 8) & 0xff);
+ n4 = (laddr & 0xff);
+
+ m->m_len = bptr - m->m_data; /* Adjust length */
+ m->m_len += sprintf(bptr,"ORT %d,%d,%d,%d,%d,%d\r\n%s",
+ n1, n2, n3, n4, n5, n6, x==7?buff:"");
+ return 1;
+ } else if ((bptr = (char *)strstr(m->m_data, "27 Entering")) != NULL) {
+ /*
+ * Need to emulate the PASV response
+ */
+ x = sscanf(bptr, "27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%256[^\177]",
+ &n1, &n2, &n3, &n4, &n5, &n6, buff);
+ if (x < 6)
+ return 1;
+
+ laddr = htonl((n1 << 24) | (n2 << 16) | (n3 << 8) | (n4));
+ lport = htons((n5 << 8) | (n6));
+
+ if ((so = solisten(0, laddr, lport, SS_FACCEPTONCE)) == NULL)
+ return 1;
+
+ n6 = ntohs(so->so_fport);
+
+ n5 = (n6 >> 8) & 0xff;
+ n6 &= 0xff;
+
+ laddr = ntohl(so->so_faddr.s_addr);
+
+ n1 = ((laddr >> 24) & 0xff);
+ n2 = ((laddr >> 16) & 0xff);
+ n3 = ((laddr >> 8) & 0xff);
+ n4 = (laddr & 0xff);
+
+ m->m_len = bptr - m->m_data; /* Adjust length */
+ m->m_len += sprintf(bptr,"27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s",
+ n1, n2, n3, n4, n5, n6, x==7?buff:"");
+
+ return 1;
+ }
+
+ return 1;
+
+ case EMU_KSH:
+ /*
+ * The kshell (Kerberos rsh) and shell services both pass
+ * a local port port number to carry signals to the server
+ * and stderr to the client. It is passed at the beginning
+ * of the connection as a NUL-terminated decimal ASCII string.
+ */
+ so->so_emu = 0;
+ for (lport = 0, i = 0; i < m->m_len-1; ++i) {
+ if (m->m_data[i] < '0' || m->m_data[i] > '9')
+ return 1; /* invalid number */
+ lport *= 10;
+ lport += m->m_data[i] - '0';
+ }
+ if (m->m_data[m->m_len-1] == '\0' && lport != 0 &&
+ (so = solisten(0, so->so_laddr.s_addr, htons(lport), SS_FACCEPTONCE)) != NULL)
+ m->m_len = sprintf(m->m_data, "%d", ntohs(so->so_fport))+1;
+ return 1;
+
+ case EMU_IRC:
+ /*
+ * Need to emulate DCC CHAT, DCC SEND and DCC MOVE
+ */
+ *(m->m_data+m->m_len) = 0; /* NULL terminate the string for strstr */
+ if ((bptr = (char *)strstr(m->m_data, "DCC")) == NULL)
+ return 1;
+
+ /* The %256s is for the broken mIRC */
+ if (sscanf(bptr, "DCC CHAT %256s %u %u", buff, &laddr, &lport) == 3) {
+ if ((so = solisten(0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL)
+ return 1;
+
+ m->m_len = bptr - m->m_data; /* Adjust length */
+ m->m_len += sprintf(bptr, "DCC CHAT chat %lu %u%c\n",
+ (unsigned long)ntohl(so->so_faddr.s_addr),
+ ntohs(so->so_fport), 1);
+ } else if (sscanf(bptr, "DCC SEND %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) {
+ if ((so = solisten(0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL)
+ return 1;
+
+ m->m_len = bptr - m->m_data; /* Adjust length */
+ m->m_len += sprintf(bptr, "DCC SEND %s %lu %u %u%c\n",
+ buff, (unsigned long)ntohl(so->so_faddr.s_addr),
+ ntohs(so->so_fport), n1, 1);
+ } else if (sscanf(bptr, "DCC MOVE %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) {
+ if ((so = solisten(0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL)
+ return 1;
+
+ m->m_len = bptr - m->m_data; /* Adjust length */
+ m->m_len += sprintf(bptr, "DCC MOVE %s %lu %u %u%c\n",
+ buff, (unsigned long)ntohl(so->so_faddr.s_addr),
+ ntohs(so->so_fport), n1, 1);
+ }
+ return 1;
+
+ case EMU_REALAUDIO:
+ /*
+ * RealAudio emulation - JP. We must try to parse the incoming
+ * data and try to find the two characters that contain the
+ * port number. Then we redirect an udp port and replace the
+ * number with the real port we got.
+ *
+ * The 1.0 beta versions of the player are not supported
+ * any more.
+ *
+ * A typical packet for player version 1.0 (release version):
+ *
+ * 0000:50 4E 41 00 05
+ * 0000:00 01 00 02 1B D7 00 00 67 E6 6C DC 63 00 12 50 .....×..gælÜc..P
+ * 0010:4E 43 4C 49 45 4E 54 20 31 30 31 20 41 4C 50 48 NCLIENT 101 ALPH
+ * 0020:41 6C 00 00 52 00 17 72 61 66 69 6C 65 73 2F 76 Al..R..rafiles/v
+ * 0030:6F 61 2F 65 6E 67 6C 69 73 68 5F 2E 72 61 79 42 oa/english_.rayB
+ *
+ * Now the port number 0x1BD7 is found at offset 0x04 of the
+ * Now the port number 0x1BD7 is found at offset 0x04 of the
+ * second packet. This time we received five bytes first and
+ * then the rest. You never know how many bytes you get.
+ *
+ * A typical packet for player version 2.0 (beta):
+ *
+ * 0000:50 4E 41 00 06 00 02 00 00 00 01 00 02 1B C1 00 PNA...........Á.
+ * 0010:00 67 75 78 F5 63 00 0A 57 69 6E 32 2E 30 2E 30 .guxõc..Win2.0.0
+ * 0020:2E 35 6C 00 00 52 00 1C 72 61 66 69 6C 65 73 2F .5l..R..rafiles/
+ * 0030:77 65 62 73 69 74 65 2F 32 30 72 65 6C 65 61 73 website/20releas
+ * 0040:65 2E 72 61 79 53 00 00 06 36 42 e.rayS...6B
+ *
+ * Port number 0x1BC1 is found at offset 0x0d.
+ *
+ * This is just a horrible switch statement. Variable ra tells
+ * us where we're going.
+ */
+
+ bptr = m->m_data;
+ while (bptr < m->m_data + m->m_len) {
+ u_short p;
+ static int ra = 0;
+ char ra_tbl[4];
+
+ ra_tbl[0] = 0x50;
+ ra_tbl[1] = 0x4e;
+ ra_tbl[2] = 0x41;
+ ra_tbl[3] = 0;
+
+ switch (ra) {
+ case 0:
+ case 2:
+ case 3:
+ if (*bptr++ != ra_tbl[ra]) {
+ ra = 0;
+ continue;
+ }
+ break;
+
+ case 1:
+ /*
+ * We may get 0x50 several times, ignore them
+ */
+ if (*bptr == 0x50) {
+ ra = 1;
+ bptr++;
+ continue;
+ } else if (*bptr++ != ra_tbl[ra]) {
+ ra = 0;
+ continue;
+ }
+ break;
+
+ case 4:
+ /*
+ * skip version number
+ */
+ bptr++;
+ break;
+
+ case 5:
+ /*
+ * The difference between versions 1.0 and
+ * 2.0 is here. For future versions of
+ * the player this may need to be modified.
+ */
+ if (*(bptr + 1) == 0x02)
+ bptr += 8;
+ else
+ bptr += 4;
+ break;
+
+ case 6:
+ /* This is the field containing the port
+ * number that RA-player is listening to.
+ */
+ lport = (((u_char*)bptr)[0] << 8)
+ + ((u_char *)bptr)[1];
+ if (lport < 6970)
+ lport += 256; /* don't know why */
+ if (lport < 6970 || lport > 7170)
+ return 1; /* failed */
+
+ /* try to get udp port between 6970 - 7170 */
+ for (p = 6970; p < 7071; p++) {
+ if (udp_listen( htons(p),
+ so->so_laddr.s_addr,
+ htons(lport),
+ SS_FACCEPTONCE)) {
+ break;
+ }
+ }
+ if (p == 7071)
+ p = 0;
+ *(u_char *)bptr++ = (p >> 8) & 0xff;
+ *(u_char *)bptr++ = p & 0xff;
+ ra = 0;
+ return 1; /* port redirected, we're done */
+ break;
+
+ default:
+ ra = 0;
+ }
+ ra++;
+ }
+ return 1;
+
+ default:
+ /* Ooops, not emulated, won't call tcp_emu again */
+ so->so_emu = 0;
+ return 1;
+ }
+}
+
+/*
+ * Do misc. config of SLiRP while its running.
+ * Return 0 if this connections is to be closed, 1 otherwise,
+ * return 2 if this is a command-line connection
+ */
+int
+tcp_ctl(so)
+ struct socket *so;
+{
+#if 0
+ struct sbuf *sb = &so->so_snd;
+ int command;
+ struct ex_list *ex_ptr;
+ int do_pty;
+ struct socket *tmpso;
+
+ DEBUG_CALL("tcp_ctl");
+ DEBUG_ARG("so = %lx", (long )so);
+
+ /*
+ * Check if they're authorised
+ */
+ if (ctl_addr.s_addr && (ctl_addr.s_addr == -1 || (so->so_laddr.s_addr != ctl_addr.s_addr))) {
+ sb->sb_cc = sprintf(sb->sb_wptr,"Error: Permission denied.\r\n");
+ sb->sb_wptr += sb->sb_cc;
+ return 0;
+ }
+
+ command = (ntohl(so->so_faddr.s_addr) & 0xff);
+
+ switch(command) {
+ default: /* Check for exec's */
+
+ /*
+ * Check if it's pty_exec
+ */
+ for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
+ if (ex_ptr->ex_fport == so->so_fport &&
+ command == ex_ptr->ex_addr) {
+ do_pty = ex_ptr->ex_pty;
+ goto do_exec;
+ }
+ }
+
+ /*
+ * Nothing bound..
+ */
+ /* tcp_fconnect(so); */
+
+ /* FALLTHROUGH */
+ case CTL_ALIAS:
+ sb->sb_cc = sprintf(sb->sb_wptr,
+ "Error: No application configured.\r\n");
+ sb->sb_wptr += sb->sb_cc;
+ return(0);
+
+ do_exec:
+ DEBUG_MISC((dfd, " executing %s \n",ex_ptr->ex_exec));
+ return(fork_exec(so, ex_ptr->ex_exec, do_pty));
+
+ case CTL_CMD:
+ for (tmpso = tcb.so_next; tmpso != &tcb; tmpso = tmpso->so_next) {
+ if (tmpso->so_emu == EMU_CTL &&
+ !(tmpso->so_tcpcb?
+ (tmpso->so_tcpcb->t_state & (TCPS_TIME_WAIT|TCPS_LAST_ACK))
+ :0)) {
+ /* Ooops, control connection already active */
+ sb->sb_cc = sprintf(sb->sb_wptr,"Sorry, already connected.\r\n");
+ sb->sb_wptr += sb->sb_cc;
+ return 0;
+ }
+ }
+ so->so_emu = EMU_CTL;
+ ctl_password_ok = 0;
+ sb->sb_cc = sprintf(sb->sb_wptr, "Slirp command-line ready (type \"help\" for help).\r\nSlirp> ");
+ sb->sb_wptr += sb->sb_cc;
+ do_echo=-1;
+ return(2);
+ }
+#else
+ return 0;
+#endif
+}