// tcp.c - TCP module

//

// © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.

//

/*

 * This file is part of zsh, the Z shell.

 *

 * Copyright (c) 1998-2001 Peter Stephenson

 * All rights reserved.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and to distribute modified versions of this software for any

 * purpose, provided that the above copyright notice and the following

 * two paragraphs appear in all copies of this software.

 *

 * In no event shall Peter Stephenson or the Zsh Development

 * Group be liable to any party for direct, indirect, special, incidental,

 * or consequential damages arising out of the use of this software and

 * its documentation, even if Peter Stephenson, and the Zsh

 * Development Group have been advised of the possibility of such damage.

 *

 * Peter Stephenson and the Zsh Development Group specifically

 * disclaim any warranties, including, but not limited to, the implied

 * warranties of merchantability and fitness for a particular purpose.  The

 * software provided hereunder is on an "as is" basis, and Peter Stephenson

 * and the Zsh Development Group have no obligation to provide maintenance,

 * support, updates, enhancements, or modifications.

 *

 */

/*

 * We need to include the zsh headers later to avoid clashes with

 * the definitions on some systems, however we need the configuration

 * file to decide whether we can include netinet/in_systm.h, which

 * doesn't exist on cygwin.

 */

#include "tcp.h"

#include "tcp.mdh"

#ifdef __SYMBIAN32__

#ifdef __WINSCW__

#pragma warn_unusedarg off

#endif//__WINSCW__

#endif//__SYMBIAN32__

#ifdef __SYMBIAN32__

#include "dummy.h"

#endif //__SYMBIAN32__

/*

 * We use poll() in preference to select because some subset of manuals says

 * that's the thing to do, plus it's a bit less fiddly.  I don't actually

 * have access to a system with poll but not select, however, though

 * both bits of the code have been tested on a machine with both.

 */

#ifdef HAVE_POLL_H

#ifndef __SYMBIAN32__

# include <sys/poll.h>

#else

# include "poll.h"

#endif

#endif

#if defined(HAVE_POLL) && !defined(POLLIN) && !defined(POLLNORM)

# undef HAVE_POLL

#endif

#ifdef USE_LOCAL_H_ERRNO

int h_errno;

#endif

/* We use the RFC 2553 interfaces.  If the functions don't exist in the

 * library, simulate them. */

#ifndef INET_ADDRSTRLEN

# define INET_ADDRSTRLEN 16

#endif

#ifndef INET6_ADDRSTRLEN

# define INET6_ADDRSTRLEN 46

#endif

/**/

#ifndef HAVE_INET_NTOP

/**/

mod_export char const *

zsh_inet_ntop(int af, void const *cp, char *buf, size_t len)

{       

    if (af != AF_INET) {

	errno = EAFNOSUPPORT;

	return NULL;

    } 

    if (len < INET_ADDRSTRLEN) {

	errno = ENOSPC;

	return NULL;

    }

    strcpy(buf, inet_ntoa(*(struct in_addr *)cp));

    return buf;

}

/**/

#else /* !HAVE_INET_NTOP */

/**/

# define zsh_inet_ntop inet_ntop

/**/

#endif /* !HAVE_INET_NTOP */

/**/

#ifndef HAVE_INET_ATON

# ifndef INADDR_NONE

#  define INADDR_NONE 0xffffffffUL

# endif

/**/

mod_export int zsh_inet_aton(char const *src, struct in_addr *dst)

{

    return (dst->s_addr = inet_addr(src)) != INADDR_NONE;

}

/**/

#else /* !HAVE_INET_ATON */

/**/

# define zsh_inet_aton inet_aton

/**/

#endif /* !HAVE_INET_ATON */

/**/

#ifndef HAVE_INET_PTON

/**/

mod_export int

zsh_inet_pton(int af, char const *src, void *dst)

{

    if (af != AF_INET) {

	errno = EAFNOSUPPORT;

	return -1;

    }

    return !!zsh_inet_aton(src, dst);

}

#else /* !HAVE_INET_PTON */

# define zsh_inet_pton inet_pton

/**/

#endif /* !HAVE_INET_PTON */

/**/

#ifndef HAVE_GETIPNODEBYNAME

/**/

# ifndef HAVE_GETHOSTBYNAME2

/**/

mod_export struct hostent *

zsh_gethostbyname2(char const *name, int af)

{

    if (af != AF_INET) {

	h_errno = NO_RECOVERY;

	return NULL;

    }

    return gethostbyname(name);

}

/**/

#else /* !HAVE_GETHOSTBYNAME2 */

/**/

# define zsh_gethostbyname2 gethostbyname2

/**/

# endif /* !HAVE_GETHOSTBYNAME2 */

/* note: this is not a complete implementation.  If ignores the flags,

   and does not provide the memory allocation of the standard interface.

   Each returned structure will overwrite the previous one. */

/**/

mod_export struct hostent *

zsh_getipnodebyname(char const *name, int af, UNUSED(int flags), int *errorp)

{

    static struct hostent ahe;

    static char nbuf[16];

    static char *addrlist[] = { nbuf, NULL };

# ifdef SUPPORT_IPV6

    static char pbuf[INET6_ADDRSTRLEN];

# else

    static char pbuf[INET_ADDRSTRLEN];

# endif

    struct hostent *he;

    if (zsh_inet_pton(af, name, nbuf) == 1) {

	zsh_inet_ntop(af, nbuf, pbuf, sizeof(pbuf));

	ahe.h_name = pbuf;

	ahe.h_aliases = addrlist+1;

	ahe.h_addrtype = af;

	ahe.h_length = (af == AF_INET) ? 4 : 16;

	ahe.h_addr_list = addrlist;

	return &ahe;

    }

    he = (struct hostent *)zsh_gethostbyname2(name, af);

    if (!he)

	*errorp = h_errno;

    return he;

}

/**/

mod_export void

freehostent(UNUSED(struct hostent *ptr))

{

}

/**/

#else /* !HAVE_GETIPNODEBYNAME */

/**/

# define zsh_getipnodebyname getipnodebyname

/**/

#endif /* !HAVE_GETIPNODEBYNAME */

LinkList ztcp_sessions;

/* "allocate" a tcp_session */

static Tcp_session

zts_alloc(int ztflags)

{

    Tcp_session sess;

    sess = (Tcp_session)zshcalloc(sizeof(struct tcp_session));

    if (!sess) return NULL;

    sess->fd=-1;

    sess->flags=ztflags;

    zinsertlinknode(ztcp_sessions, lastnode(ztcp_sessions), (void *)sess);

    return sess;

}

/**/

mod_export Tcp_session

tcp_socket(int domain, int type, int protocol, int ztflags)

{

    Tcp_session sess;

    sess = zts_alloc(ztflags);

    if (!sess) return NULL;

    sess->fd = socket(domain, type, protocol);

    return sess;

}

static int

ztcp_free_session(Tcp_session sess)

{

    zfree(sess, sizeof(struct tcp_session));

    return 0;

}

static int

zts_delete(Tcp_session sess)

{

    LinkNode node;

    node = linknodebydatum(ztcp_sessions, (void *)sess);

    if (!node)

    {

	return 1;

    }

    ztcp_free_session(getdata(node));

    remnode(ztcp_sessions, node);

    return 0;

}

static Tcp_session

zts_byfd(int fd)

{

    LinkNode node;

    for (node = firstnode(ztcp_sessions); node; incnode(node))

	if (((Tcp_session)getdata(node))->fd == fd)

	    return (Tcp_session)getdata(node);

    return NULL;

}

static void

tcp_cleanup(void)

{

    LinkNode node, next;

    for (node = firstnode(ztcp_sessions); node; node = next) {

	next = node->next;

	tcp_close((Tcp_session)getdata(node));

    }

}

/**/

mod_export int

tcp_close(Tcp_session sess)

{

    int err;

    if (sess)

    {  

	if (sess->fd != -1)

	{

	    err = close(sess->fd);

	    if (err)

		zwarn("connection close failed: %e", NULL, errno);

	}

	zts_delete(sess);

	return 0;

    }

    return -1;

}

/**/

mod_export int

tcp_connect(Tcp_session sess, char *addrp, struct hostent *zhost, int d_port)

{

    int salen;

#ifdef SUPPORT_IPV6

    if (zhost->h_addrtype==AF_INET6) {

	memcpy(&(sess->peer.in6.sin6_addr), addrp, zhost->h_length);

	sess->peer.in6.sin6_port = d_port;

	sess->peer.in6.sin6_flowinfo = 0;

# ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_SCOPE_ID

	sess->peer.in6.sin6_scope_id = 0;

# endif

	sess->peer.in6.sin6_family = zhost->h_addrtype;

	salen = sizeof(struct sockaddr_in6);

    } else

#endif /* SUPPORT_IPV6 */

    {

	memcpy(&(sess->peer.in.sin_addr), addrp, zhost->h_length);

	sess->peer.in.sin_port = d_port;

	sess->peer.in.sin_family = zhost->h_addrtype;

	salen = sizeof(struct sockaddr_in);

    }

    return connect(sess->fd, (struct sockaddr *)&(sess->peer), salen);

}

static int

bin_ztcp(char *nam, char **args, Options ops, UNUSED(int func))

{

    int herrno, err=1, destport, force=0, verbose=0, test=0, targetfd=0;

    ZSOCKLEN_T  len;

    char **addrp, *desthost, *localname, *remotename;

    struct hostent *zthost = NULL, *ztpeer = NULL;

    struct servent *srv;

    Tcp_session sess = NULL;

    if (OPT_ISSET(ops,'f'))

	force = 1;

    if (OPT_ISSET(ops,'v'))

	verbose = 1;

    if (OPT_ISSET(ops,'t'))

        test = 1;

    if (OPT_ISSET(ops,'d')) {

	targetfd = atoi(OPT_ARG(ops,'d'));

	if (!targetfd) {

	    zwarnnam(nam, "%s is an invalid argument to -d",

		     OPT_ARG(ops,'d'), 0);

	    return 1;

	}

    }

    if (OPT_ISSET(ops,'c')) {

	if (!args[0]) {

	    tcp_cleanup();

	}

	else {

	    targetfd = atoi(args[0]);

	    sess = zts_byfd(targetfd);

	    if(!targetfd) {

		zwarnnam(nam, "%s is an invalid argument to -c", args[0], 0);

		return 1;

	    }

	    if (sess)

	    {

		if ((sess->flags & ZTCP_ZFTP) && !force)

		{

		    zwarnnam(nam, "use -f to force closure of a zftp control connection", NULL, 0);

		    return 1;

		}

		tcp_close(sess);

		return 0;

	    }

	    else

	    {

		zwarnnam(nam, "fd %s not found in tcp table", args[0], 0);

		return 1;

	    }

	}

    }

    else if (OPT_ISSET(ops,'l')) {

	int lport = 0;

	if (!args[0]) {

	    zwarnnam(nam, "-l requires an argument", NULL, 0);

	    return 1;

	}

	srv = getservbyname(args[0], "tcp");

	if (srv)

	    lport = srv->s_port;

	else

	    lport = htons(atoi(args[0]));

	if (!lport) { zwarnnam(nam, "bad service name or port number", NULL, 0);

	return 1;

	}

	sess = tcp_socket(PF_INET, SOCK_STREAM, 0, ZTCP_LISTEN);

	if (!sess) {

	    zwarnnam(nam, "unable to allocate a TCP session slot", NULL, 0);

	    return 1;

	}

#ifdef SO_OOBINLINE

	len = 1;

	setsockopt(sess->fd, SOL_SOCKET, SO_OOBINLINE, (char *)&len, sizeof(len));

#endif

#ifndef __SYMBIAN32__

	if (!zsh_inet_aton("0.0.0.0", &(sess->sock.in.sin_addr)))

	{

	    zwarnnam(nam, "bad address: %s", "0.0.0.0", 0);

	    return 1;

	}

#endif//__SYMBIAN32__

	sess->sock.in.sin_family = AF_INET;

	sess->sock.in.sin_port = lport;

	if (bind(sess->fd, (struct sockaddr *)&sess->sock.in, sizeof(struct sockaddr_in)))

	{

	    char buf[DIGBUFSIZE];

	    convbase(buf, (zlong)lport, 10);

	    zwarnnam(nam, "could not bind to port %s: %e", buf, errno);

	    tcp_close(sess);

	    return 1;

	}

	if (listen(sess->fd, 1))

	{

	    zwarnnam(nam, "could not listen on socket: %e", NULL, errno);

	    tcp_close(sess);

	    return 1;

	}

	if (targetfd) {

	    redup(sess->fd,targetfd);

	    sess->fd = targetfd;

	}

	else {

	    /* move the fd since no one will want to read from it */

	    sess->fd = movefd(sess->fd);

	}

	setiparam("REPLY", sess->fd);

	if (verbose)

	    printf("%d listener is on fd %d\n", ntohs(sess->sock.in.sin_port), sess->fd);

	return 0;

    }

    else if (OPT_ISSET(ops,'a'))

    {

	int lfd, rfd;

	if (!args[0]) {

	    zwarnnam(nam, "-a requires an argument", NULL, 0);

	    return 1;

	}

	lfd = atoi(args[0]);

	if (!lfd) {

	    zwarnnam(nam, "invalid numerical argument", NULL, 0);

	    return 1;

	}

	sess = zts_byfd(lfd);

	if (!sess) {

	    zwarnnam(nam, "fd %s is not registered as a tcp connection", args[0], 0);

	    return 1;

	}

	if (!(sess->flags & ZTCP_LISTEN))

	{

	    zwarnnam(nam, "tcp connection not a listener", NULL, 0);

	    return 1;

	}

	if (test) {

#if defined(HAVE_POLL) || defined(HAVE_SELECT)

# ifdef HAVE_POLL

	    struct pollfd pfd;

	    int ret;

	    pfd.fd = lfd;

	    pfd.events = POLLIN;

	    if ((ret = poll(&pfd, 1, 0)) == 0) return 1;

	    else if (ret == -1)

	    {

		zwarnnam(nam, "poll error: %e", NULL, errno);

		return 1;

	    }

# else