[fwd] / inet.c

/* -*-c-*-
 *
 * Protocol specific definitions for IPv4 sockets
 *
 * (c) 1999 Straylight/Edgeware
 */

/*----- Licensing notice --------------------------------------------------* 
 *
 * This file is part of the `fw' port forwarder.
 *
 * `fw' is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * `fw' is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with `fw'; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#include "config.h"

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <sys/types.h>
#include <unistd.h>

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>

#include <mLib/alloc.h>
#include <mLib/dstr.h>
#include <mLib/fdflags.h>
#include <mLib/report.h>
#include <mLib/sub.h>

#include "acl.h"
#include "addr.h"
#include "conf.h"
#include "fw.h"
#include "identify.h"
#include "inet.h"
#include "privconn.h"
#include "reffd.h"
#include "scan.h"
#include "socket.h"

/*----- Data structures ---------------------------------------------------*/

typedef struct inet_addrx {
  addr a;
  struct sockaddr_in sin;
} inet_addrx;

typedef struct inet_opts {
  addr_opts ao;
  struct in_addr bind;
} inet_opts;

typedef struct inet_srcopts {
  inet_opts io;
  acl_entry *acl;
  acl_entry **acltail;
} inet_srcopts;

typedef struct inet_targopts {
  inet_opts io;
  int ipriv;
} inet_targopts;

#define ADDRF_PRIVCONN 16u

static inet_srcopts inet_globalsrc =
  { { { 0 }, { INADDR_ANY } }, 0, &inet_globalsrc.acl };
static inet_targopts inet_globaltarg =
  { { { 0 }, { INADDR_ANY } } };

/*----- Protocol operations -----------------------------------------------*/

/* --- @read@ --- */

static addr *inet_read(scanner *sc, unsigned type)
{
  inet_addrx *ia = xmalloc(sizeof(*ia));

  ia->a.ops = &inet_ops;
  ia->a.sz = sizeof(struct sockaddr_in);
  memset(&ia->sin, 0, sizeof(ia->sin));
  ia->sin.sin_family = AF_INET;

  /* --- Read the host address part --- */

  switch (type) {
    case ADDR_SRC:
      if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "port") == 0)
	token(sc);
      ia->sin.sin_addr.s_addr = htonl(INADDR_ANY);
      break;
    case ADDR_DEST: {
      struct hostent *h;
      dstr d = DSTR_INIT;
      conf_name(sc, '.', &d);
      if ((h = gethostbyname(d.buf)) == 0)
	error(sc, "couldn't resolve Internet address `%s'", d.buf);
      memcpy(&ia->sin.sin_addr, h->h_addr, sizeof(struct in_addr));
      dstr_destroy(&d);
      if (sc->t == ':')
	token(sc);
    } break;
  }

  /* --- Read the port number --- */

  {
    struct servent *s;

    if (sc->t != CTOK_WORD)
      error(sc, "parse error, TCP port expected");
    if (isdigit((unsigned char)sc->d.buf[0]))
      ia->sin.sin_port = htons(atoi(sc->d.buf));
    else if ((s = getservbyname(sc->d.buf, "tcp")) == 0)
      error(sc, "unknown tcp service `%s'", sc->d.buf);
    else
      ia->sin.sin_port = s->s_port;
    token(sc);
  }

  return (&ia->a);
}

/* --- @destroy@ --- */

static void inet_destroy(addr *a)
{
  inet_addrx *ia = (inet_addrx *)a;
  DESTROY(ia);
}

/* --- @print@ --- */

static void inet_print(addr *a, unsigned type, dstr *d)
{
  inet_addrx *ia = (inet_addrx *)a;
  switch (type) {
    case ADDR_SRC:
      dstr_putf(d, "inet:%u", (unsigned)ntohs(ia->sin.sin_port));
      break;
    case ADDR_DEST:
      dstr_putf(d, "inet:%s:%u",
		inet_ntoa(ia->sin.sin_addr),
		(unsigned)ntohs(ia->sin.sin_port));
      break;
  }
}

/* --- @initopts@ --- */

static addr_opts *inet_initsrcopts(void)
{
  inet_srcopts *io = CREATE(inet_srcopts);
  *io = inet_globalsrc;
  io->acl = 0;
  io->acltail = &io->acl;
  return (&io->io.ao);
}

static addr_opts *inet_inittargopts(void)
{
  inet_targopts *io = CREATE(inet_targopts);
  *io = inet_globaltarg;
  io->ipriv = -1;
  return (&io->io.ao);
}

/* --- @option@ --- */

static void addropt(scanner *sc, inet_opts *io)
{
  dstr d = DSTR_INIT;
  struct hostent *h;

  token(sc);
  if (sc->t == '=')
    token(sc);
  if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "any") == 0)
    io->bind.s_addr = INADDR_ANY;
  else {
    conf_name(sc, '.', &d);
    if ((h = gethostbyname(d.buf)) == 0)
      error(sc, "couldn't resolve address `%s'", d.buf);
    memcpy(&io->bind, h->h_addr, sizeof(struct in_addr));
  }
}

static int srcopt(scanner *sc, addr_opts *ao)
{
  inet_srcopts *io = (inet_srcopts *)ao;
  unsigned act;

  CONF_BEGIN(sc, "source", "Internet socket source")

  /* --- Initialization --- */

  if (!io) {
    if (!inet_globalsrc.acltail)
      inet_globalsrc.acltail = &inet_globalsrc.acl;
    io = &inet_globalsrc;
  }

  /* --- Source address configuration --- */

  if (strcmp(sc->d.buf, "addr") == 0) {
    addropt(sc, &io->io);
    CONF_ACCEPT;
  }

  /* --- Access control limitations --- */

  if ((strcmp(sc->d.buf, "allow") == 0 && (act = ACL_ALLOW, 1)) ||
       (strcmp(sc->d.buf, "deny") == 0 && (act = ACL_DENY, 1))) {
    struct hostent *h;
    struct netent *n;
    struct in_addr a, m;
    dstr d = DSTR_INIT;

    /* --- Find out what's going on --- */

    token(sc);
    if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "from") == 0)
      token(sc);

    if (sc->t == CTOK_WORD && (strcmp(sc->d.buf, "priv") == 0 ||
			       strcmp(sc->d.buf, "priv-port") == 0)) {
      acl_addpriv(&io->acltail, act);
      token(sc);
    } else {
      if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "host") == 0)
	token(sc);

      /* --- Find the host or network address --- */

      conf_name(sc, '.', &d);
#ifdef HAVE_GETNETBYNAME
      if ((n = getnetbyname(d.buf)) != 0)
	a.s_addr = htonl(n->n_net);
      else
#endif
	if ((h = gethostbyname(d.buf)) == 0)
	  error(sc, "couldn't resolve address `%s'", d.buf);
	else
	  memcpy(&a, h->h_addr, sizeof(struct in_addr));

      /* --- Find the netmask, if any --- */

      if (sc->t != '/')
	m.s_addr = ~0ul;
      else {
	token(sc);
	DRESET(&d);
	conf_name(sc, '.', &d);
	if (strchr(d.buf, '.') == 0) {
	  int n = atoi(d.buf);
	  if (n == 0)
	    m.s_addr = 0;
	  else
	    m.s_addr = htonl((~0ul << (32 - n)) & 0xffffffff);
	} else {
#ifdef HAVE_INET_ATON
	  if (!inet_aton(d.buf, &m))
	    error(sc, "bad netmask `%s'", d.buf);
#else
	  m.s_addr = inet_addr(d.buf);
#endif
	}
      }
      dstr_destroy(&d);

      /* --- Add the access control entry --- */

      acl_addhost(&io->acltail, act, a, m);
    }
    CONF_ACCEPT;
  }

  /* --- Anything unrecognized --- */

  CONF_END;
}

static int targopt(scanner *sc, addr_opts *ao)
{
  inet_targopts *io = (inet_targopts *)ao;

  CONF_BEGIN(sc, "dest", "Internet socket target");
  if (strcmp(sc->d.buf, "addr") == 0) {
    addropt(sc, &io->io);
    CONF_ACCEPT;
  }
  if (strcmp(sc->d.buf, "priv") == 0 ||
      strcmp(sc->d.buf, "priv-port") == 0) {
    token(sc);
    if (sc->t == '=') token(sc);
    if (conf_enum(sc, "no,yes", ENUM_ABBREV, "privileged connection status"))
      io->io.ao.f |= ADDRF_PRIVCONN;
    else
      io->io.ao.f &= ~ADDRF_PRIVCONN;
    CONF_ACCEPT;
  }
  CONF_END;
}

static int inet_option(scanner *sc, addr_opts *ao, unsigned type)
{
  CONF_BEGIN(sc, "inet", "Internet socket");
  if (type != ADDR_DEST && srcopt(sc, ao))
    CONF_ACCEPT;
  if (type != ADDR_SRC && targopt(sc, ao))
    CONF_ACCEPT;
  CONF_END;
}

/* --- @confirm@ --- */

static void inet_confirm(addr *a, unsigned type, addr_opts *ao)
{
  inet_addrx *ia = (inet_addrx *)a;

  switch (type) {
    case ADDR_DEST: {
      inet_targopts *io = (inet_targopts *)ao;
      if ((io->io.ao.f & ADDRF_PRIVCONN) &&
	  (io->ipriv = privconn_adddest(ia->sin.sin_addr,
					ia->sin.sin_port)) < 0)
	die(1, "couldn't add privileged connection target (too late)");
    } break;
  }
}

/* --- @freeopts@ --- */

static void inet_freesrcopts(addr_opts *ao)
{
  inet_srcopts *io = (inet_srcopts *)ao;
  acl_free(io->acl);
  DESTROY(io);
}

static void inet_freetargopts(addr_opts *ao)
{
  inet_targopts *io = (inet_targopts *)ao;
  DESTROY(io);
}

/* --- @bind@ --- */

static int inet_bind(addr *a, addr_opts *ao)
{
  inet_addrx *ia = (inet_addrx *)a;
  inet_srcopts *io = (inet_srcopts *)ao;
  struct sockaddr_in sin;
  int opt = 1;
  int fd;

  if ((fd = socket(PF_INET, SOCK_STREAM, 0)) < 0)
    goto fail_0;
  setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
  fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
  sin = ia->sin;
  sin.sin_addr = io->io.bind;
  if (bind(fd, (struct sockaddr *)&sin, sizeof(ia->sin)))
    goto fail_1;
  return (fd);

fail_1:
  close(fd);
fail_0:
  return (-1);
}

/* --- @accept@ --- */

static reffd *inet_accept(int fd, addr_opts *ao, const char *desc)
{
  inet_srcopts *io = (inet_srcopts *)ao;
  int nfd;
  id_req q;
  size_t lsinsz = sizeof(q.lsin), rsinsz = sizeof(q.rsin);
  int act = ACL_ALLOW;

  /* --- Accept the new connection --- */

  if ((nfd = accept(fd, (struct sockaddr *)&q.rsin, &rsinsz)) < 0)
    return (0);
  if (getsockname(nfd, (struct sockaddr *)&q.lsin, &lsinsz)) {
    close(nfd);
    return (0);
  }
  q.desc = desc;
  q.r = reffd_init(nfd);

  /* --- Find out whether this connection is allowed --- */

  if (!acl_check(io->acl, q.rsin.sin_addr, ntohs(q.rsin.sin_port), &act))
    acl_check(inet_globalsrc.acl, q.rsin.sin_addr,
	      ntohs(q.rsin.sin_port), &act);
  if (act != ACL_ALLOW) {
    q.act = "refused";
    if (!(io->io.ao.f & ADDRF_NOLOG))
      identify(&q);
    REFFD_DEC(q.r);
    return (0);
  }

  /* --- Everything seems to be OK --- */

  q.act = "accepted";
  if (!(io->io.ao.f & ADDRF_NOLOG))
    identify(&q);
  return (q.r);
}

/* --- @connect@ --- */

static int inet_connect(addr *a, addr_opts *ao, conn *c, endpt *e)
{
  inet_addrx *ia = (inet_addrx *)a;
  inet_targopts *io = (inet_targopts *)ao;
  int fd;

  if (io->ipriv >= 0) {
    return (privconn_connect(c, sel, io->ipriv, io->io.bind,
			     starget_connected, e));
  }
  if ((fd = socket(PF_INET, SOCK_STREAM, 0)) < 0)
    goto fail_0;
  if (io->io.bind.s_addr != INADDR_ANY) {
    struct sockaddr_in sin;
    memset(&sin, 0, sizeof(sin));
    sin.sin_family = AF_INET;
    sin.sin_addr = io->io.bind;
    sin.sin_port = 0;
    if (bind(fd, (struct sockaddr *)&sin, sizeof(sin)))
      goto fail_1;
  }
  fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
  return (conn_init(c, sel, fd, (struct sockaddr *)&ia->sin, sizeof(ia->sin),
		    starget_connected, e));
fail_1:
  close(fd);
fail_0:
  return (-1);
}

/* --- Ops table --- */

addr_ops inet_ops = {
  "inet",
  inet_read, inet_destroy, inet_print,
  inet_initsrcopts, inet_option, inet_confirm, inet_freesrcopts,
  inet_bind, 0, inet_accept,
  inet_inittargopts, inet_freetargopts,
  inet_connect  
};

/*----- That's all, folks -------------------------------------------------*/
Commit	Line	Data
aa1f699e	1	/* --c--
aa1f699e	2	*
aa1f699e	3	* Protocol specific definitions for IPv4 sockets
	4	*
	5	* (c) 1999 Straylight/Edgeware
	6	*/
	7
	8	/----- Licensing notice --------------------------------------------------
	9	*
	10	* This file is part of the `fw' port forwarder.
	11	*
	12	* `fw' is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License as published by
	14	* the Free Software Foundation; either version 2 of the License, or
	15	* (at your option) any later version.
	16	*
	17	* `fw' is distributed in the hope that it will be useful,
	18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	* GNU General Public License for more details.
	21	*
	22	* You should have received a copy of the GNU General Public License
	23	* along with `fw'; if not, write to the Free Software Foundation,
	24	* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	25	*/
	26
aa1f699e	27	/----- Header files ------------------------------------------------------/
	28
	29	#include "config.h"
	30
	31	#include <ctype.h>
	32	#include <errno.h>
	33	#include <stdio.h>
	34	#include <stdlib.h>
	35	#include <string.h>
	36
	37	#include <sys/types.h>
	38	#include <unistd.h>
	39
	40	#include <sys/socket.h>
	41	#include <netinet/in.h>
	42	#include <arpa/inet.h>
	43	#include <netdb.h>
	44
	45	#include <mLib/alloc.h>
	46	#include <mLib/dstr.h>
0ac54f22	47	#include <mLib/fdflags.h>
aa1f699e	48	#include <mLib/report.h>
	49	#include <mLib/sub.h>
	50
	51	#include "acl.h"
	52	#include "addr.h"
	53	#include "conf.h"
0ac54f22	54	#include "fw.h"
aa1f699e	55	#include "identify.h"
aa1f699e	56	#include "inet.h"
ee599f55	57	#include "privconn.h"
aa1f699e	58	#include "reffd.h"
aa1f699e	59	#include "scan.h"
0ac54f22	60	#include "socket.h"
aa1f699e	61
	62	/----- Data structures ---------------------------------------------------/
	63
	64	typedef struct inet_addrx {
	65	addr a;
	66	struct sockaddr_in sin;
	67	} inet_addrx;
	68
	69	typedef struct inet_opts {
	70	addr_opts ao;
0ac54f22	71	struct in_addr bind;
	72	} inet_opts;
	73
	74	typedef struct inet_srcopts {
	75	inet_opts io;
aa1f699e	76	acl_entry *acl;
aa1f699e	77	acl_entry **acltail;
0ac54f22	78	} inet_srcopts;
	79
	80	typedef struct inet_targopts {
	81	inet_opts io;
ee599f55	82	int ipriv;
0ac54f22	83	} inet_targopts;
0ac54f22	84
ee599f55	85	#define ADDRF_PRIVCONN 16u
ee599f55	86
0ac54f22	87	static inet_srcopts inet_globalsrc =
	88	{ { { 0 }, { INADDR_ANY } }, 0, &inet_globalsrc.acl };
	89	static inet_targopts inet_globaltarg =
	90	{ { { 0 }, { INADDR_ANY } } };
aa1f699e	91
	92	/----- Protocol operations -----------------------------------------------/
	93
	94	/* --- @read@ --- */
	95
	96	static addr inet_read(scanner sc, unsigned type)
	97	{
	98	inet_addrx ia = xmalloc(sizeof(ia));
	99
	100	ia->a.ops = &inet_ops;
	101	ia->a.sz = sizeof(struct sockaddr_in);
e0ce9d38	102	memset(&ia->sin, 0, sizeof(ia->sin));
aa1f699e	103	ia->sin.sin_family = AF_INET;
	104
	105	/* --- Read the host address part --- */
	106
	107	switch (type) {
	108	case ADDR_SRC:
	109	if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "port") == 0)
	110	token(sc);
	111	ia->sin.sin_addr.s_addr = htonl(INADDR_ANY);
	112	break;
	113	case ADDR_DEST: {
	114	struct hostent *h;
	115	dstr d = DSTR_INIT;
	116	conf_name(sc, '.', &d);
	117	if ((h = gethostbyname(d.buf)) == 0)
	118	error(sc, "couldn't resolve Internet address `%s'", d.buf);
	119	memcpy(&ia->sin.sin_addr, h->h_addr, sizeof(struct in_addr));
	120	dstr_destroy(&d);
	121	if (sc->t == ':')
	122	token(sc);
	123	} break;
	124	}
	125
	126	/* --- Read the port number --- */
	127
	128	{
	129	struct servent *s;
	130
	131	if (sc->t != CTOK_WORD)
	132	error(sc, "parse error, TCP port expected");
	133	if (isdigit((unsigned char)sc->d.buf[0]))
	134	ia->sin.sin_port = htons(atoi(sc->d.buf));
	135	else if ((s = getservbyname(sc->d.buf, "tcp")) == 0)
	136	error(sc, "unknown tcp service `%s'", sc->d.buf);
	137	else
	138	ia->sin.sin_port = s->s_port;
	139	token(sc);
	140	}
	141
	142	return (&ia->a);
	143	}
	144
	145	/* --- @destroy@ --- */
	146
	147	static void inet_destroy(addr *a)
	148	{
	149	inet_addrx ia = (inet_addrx )a;
	150	DESTROY(ia);
	151	}
	152
	153	/* --- @print@ --- */
	154
	155	static void inet_print(addr a, unsigned type, dstr d)
	156	{
	157	inet_addrx ia = (inet_addrx )a;
	158	switch (type) {
	159	case ADDR_SRC:
	160	dstr_putf(d, "inet:%u", (unsigned)ntohs(ia->sin.sin_port));
	161	break;
	162	case ADDR_DEST:
	163	dstr_putf(d, "inet:%s:%u",
	164	inet_ntoa(ia->sin.sin_addr),
	165	(unsigned)ntohs(ia->sin.sin_port));
	166	break;
167	}
168	}
169
170	/* --- @initopts@ --- */
171
0ac54f22	172	static addr_opts *inet_initsrcopts(void)
aa1f699e	173	{
0ac54f22	174	inet_srcopts *io = CREATE(inet_srcopts);
0ac54f22	175	*io = inet_globalsrc;
aa1f699e	176	io->acl = 0;
aa1f699e	177	io->acltail = &io->acl;
0ac54f22	178	return (&io->io.ao);
	179	}
	180
	181	static addr_opts *inet_inittargopts(void)
	182	{
	183	inet_targopts *io = CREATE(inet_targopts);
	184	*io = inet_globaltarg;
ee599f55	185	io->ipriv = -1;
0ac54f22	186	return (&io->io.ao);
aa1f699e	187	}
	188
	189	/* --- @option@ --- */
	190
0ac54f22	191	static void addropt(scanner sc, inet_opts io)
aa1f699e	192	{
0ac54f22	193	dstr d = DSTR_INIT;
0ac54f22	194	struct hostent *h;
aa1f699e	195
0ac54f22	196	token(sc);
	197	if (sc->t == '=')
	198	token(sc);
	199	if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "any") == 0)
	200	io->bind.s_addr = INADDR_ANY;
	201	else {
	202	conf_name(sc, '.', &d);
	203	if ((h = gethostbyname(d.buf)) == 0)
	204	error(sc, "couldn't resolve address `%s'", d.buf);
	205	memcpy(&io->bind, h->h_addr, sizeof(struct in_addr));
	206	}
	207	}
aa1f699e	208
0ac54f22	209	static int srcopt(scanner sc, addr_opts ao)
	210	{
	211	inet_srcopts io = (inet_srcopts )ao;
aa1f699e	212	unsigned act;
aa1f699e	213
0ac54f22	214	CONF_BEGIN(sc, "source", "Internet socket source")
	215
	216	/* --- Initialization --- */
	217
	218	if (!io) {
	219	if (!inet_globalsrc.acltail)
	220	inet_globalsrc.acltail = &inet_globalsrc.acl;
	221	io = &inet_globalsrc;
	222	}
	223
	224	/* --- Source address configuration --- */
	225
	226	if (strcmp(sc->d.buf, "addr") == 0) {
	227	addropt(sc, &io->io);
	228	CONF_ACCEPT;
	229	}
	230
aa1f699e	231	/* --- Access control limitations --- */
	232
	233	if ((strcmp(sc->d.buf, "allow") == 0 && (act = ACL_ALLOW, 1)) \|\|
	234	(strcmp(sc->d.buf, "deny") == 0 && (act = ACL_DENY, 1))) {
	235	struct hostent *h;
	236	struct netent *n;
	237	struct in_addr a, m;
	238	dstr d = DSTR_INIT;
	239
0ac54f22	240	/* --- Find out what's going on --- */
aa1f699e	241
	242	token(sc);
	243	if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "from") == 0)
	244	token(sc);
aa1f699e	245
ee599f55	246	if (sc->t == CTOK_WORD && (strcmp(sc->d.buf, "priv") == 0 \|\|
ee599f55	247	strcmp(sc->d.buf, "priv-port") == 0)) {
0ac54f22	248	acl_addpriv(&io->acltail, act);
aa1f699e	249	token(sc);
0ac54f22	250	} else {
	251	if (sc->t == CTOK_WORD && strcmp(sc->d.buf, "host") == 0)
	252	token(sc);
	253
	254	/* --- Find the host or network address --- */
	255
aa1f699e	256	conf_name(sc, '.', &d);
0ac54f22	257	#ifdef HAVE_GETNETBYNAME
	258	if ((n = getnetbyname(d.buf)) != 0)
	259	a.s_addr = htonl(n->n_net);
	260	else
	261	#endif
	262	if ((h = gethostbyname(d.buf)) == 0)
	263	error(sc, "couldn't resolve address `%s'", d.buf);
aa1f699e	264	else
0ac54f22	265	memcpy(&a, h->h_addr, sizeof(struct in_addr));
	266
	267	/* --- Find the netmask, if any --- */
	268
	269	if (sc->t != '/')
	270	m.s_addr = ~0ul;
	271	else {
	272	token(sc);
	273	DRESET(&d);
	274	conf_name(sc, '.', &d);
	275	if (strchr(d.buf, '.') == 0) {
	276	int n = atoi(d.buf);
	277	if (n == 0)
	278	m.s_addr = 0;
	279	else
	280	m.s_addr = htonl((~0ul << (32 - n)) & 0xffffffff);
	281	} else {
aa1f699e	282	#ifdef HAVE_INET_ATON
0ac54f22	283	if (!inet_aton(d.buf, &m))
0ac54f22	284	error(sc, "bad netmask `%s'", d.buf);
aa1f699e	285	#else
0ac54f22	286	m.s_addr = inet_addr(d.buf);
aa1f699e	287	#endif
0ac54f22	288	}
aa1f699e	289	}
0ac54f22	290	dstr_destroy(&d);
aa1f699e	291
0ac54f22	292	/* --- Add the access control entry --- */
aa1f699e	293
0ac54f22	294	acl_addhost(&io->acltail, act, a, m);
0ac54f22	295	}
aa1f699e	296	CONF_ACCEPT;
	297	}
	298
	299	/* --- Anything unrecognized --- */
	300
	301	CONF_END;
	302	}
	303
0ac54f22	304	static int targopt(scanner sc, addr_opts ao)
	305	{
	306	inet_targopts io = (inet_targopts )ao;
	307
	308	CONF_BEGIN(sc, "dest", "Internet socket target");
	309	if (strcmp(sc->d.buf, "addr") == 0) {
	310	addropt(sc, &io->io);
	311	CONF_ACCEPT;
	312	}
ee599f55	313	if (strcmp(sc->d.buf, "priv") == 0 \|\|
	314	strcmp(sc->d.buf, "priv-port") == 0) {
	315	token(sc);
	316	if (sc->t == '=') token(sc);
	317	if (conf_enum(sc, "no,yes", ENUM_ABBREV, "privileged connection status"))
	318	io->io.ao.f \|= ADDRF_PRIVCONN;
	319	else
	320	io->io.ao.f &= ~ADDRF_PRIVCONN;
	321	CONF_ACCEPT;
	322	}
0ac54f22	323	CONF_END;
	324	}
	325
	326	static int inet_option(scanner sc, addr_opts ao, unsigned type)
	327	{
	328	CONF_BEGIN(sc, "inet", "Internet socket");
	329	if (type != ADDR_DEST && srcopt(sc, ao))
	330	CONF_ACCEPT;
	331	if (type != ADDR_SRC && targopt(sc, ao))
	332	CONF_ACCEPT;
	333	CONF_END;
	334	}
	335
ee599f55	336	/* --- @confirm@ --- */
	337
	338	static void inet_confirm(addr a, unsigned type, addr_opts ao)
	339	{
	340	inet_addrx ia = (inet_addrx )a;
	341
	342	switch (type) {
	343	case ADDR_DEST: {
	344	inet_targopts io = (inet_targopts )ao;
	345	if ((io->io.ao.f & ADDRF_PRIVCONN) &&
	346	(io->ipriv = privconn_adddest(ia->sin.sin_addr,
	347	ia->sin.sin_port)) < 0)
	348	die(1, "couldn't add privileged connection target (too late)");
	349	} break;
	350	}
	351	}
	352
0ac54f22	353	/* --- @freeopts@ --- */
	354
	355	static void inet_freesrcopts(addr_opts *ao)
	356	{
	357	inet_srcopts io = (inet_srcopts )ao;
	358	acl_free(io->acl);
	359	DESTROY(io);
	360	}
	361
	362	static void inet_freetargopts(addr_opts *ao)
	363	{
	364	inet_targopts io = (inet_targopts )ao;
	365	DESTROY(io);
	366	}
	367
	368	/* --- @bind@ --- */
	369
	370	static int inet_bind(addr a, addr_opts ao)
	371	{
	372	inet_addrx ia = (inet_addrx )a;
	373	inet_srcopts io = (inet_srcopts )ao;
	374	struct sockaddr_in sin;
	375	int opt = 1;
	376	int fd;
	377
	378	if ((fd = socket(PF_INET, SOCK_STREAM, 0)) < 0)
	379	goto fail_0;
	380	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
	381	fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
	382	sin = ia->sin;
	383	sin.sin_addr = io->io.bind;
	384	if (bind(fd, (struct sockaddr *)&sin, sizeof(ia->sin)))
	385	goto fail_1;
	386	return (fd);
	387
	388	fail_1:
	389	close(fd);
	390	fail_0:
	391	return (-1);
	392	}
	393
aa1f699e	394	/* --- @accept@ --- */
	395
	396	static reffd inet_accept(int fd, addr_opts ao, const char *desc)
	397	{
0ac54f22	398	inet_srcopts io = (inet_srcopts )ao;
aa1f699e	399	int nfd;
aa1f699e	400	id_req q;
bc241e98	401	size_t lsinsz = sizeof(q.lsin), rsinsz = sizeof(q.rsin);
0ac54f22	402	int act = ACL_ALLOW;
aa1f699e	403
	404	/* --- Accept the new connection --- */
	405
	406	if ((nfd = accept(fd, (struct sockaddr *)&q.rsin, &rsinsz)) < 0)
	407	return (0);
	408	if (getsockname(nfd, (struct sockaddr *)&q.lsin, &lsinsz)) {
	409	close(nfd);
	410	return (0);
	411	}
	412	q.desc = desc;
	413	q.r = reffd_init(nfd);
	414
	415	/* --- Find out whether this connection is allowed --- */
	416
0ac54f22	417	if (!acl_check(io->acl, q.rsin.sin_addr, ntohs(q.rsin.sin_port), &act))
	418	acl_check(inet_globalsrc.acl, q.rsin.sin_addr,
	419	ntohs(q.rsin.sin_port), &act);
	420	if (act != ACL_ALLOW) {
aa1f699e	421	q.act = "refused";
0ac54f22	422	if (!(io->io.ao.f & ADDRF_NOLOG))
aa1f699e	423	identify(&q);
	424	REFFD_DEC(q.r);
	425	return (0);
	426	}
	427
	428	/* --- Everything seems to be OK --- */
	429
	430	q.act = "accepted";
0ac54f22	431	if (!(io->io.ao.f & ADDRF_NOLOG))
aa1f699e	432	identify(&q);
	433	return (q.r);
	434	}
	435
0ac54f22	436	/* --- @connect@ --- */
aa1f699e	437
0ac54f22	438	static int inet_connect(addr a, addr_opts ao, conn c, endpt e)
aa1f699e	439	{
0ac54f22	440	inet_addrx ia = (inet_addrx )a;
	441	inet_targopts io = (inet_targopts )ao;
	442	int fd;
	443
ee599f55	444	if (io->ipriv >= 0) {
	445	return (privconn_connect(c, sel, io->ipriv, io->io.bind,
	446	starget_connected, e));
	447	}
0ac54f22	448	if ((fd = socket(PF_INET, SOCK_STREAM, 0)) < 0)
	449	goto fail_0;
	450	if (io->io.bind.s_addr != INADDR_ANY) {
	451	struct sockaddr_in sin;
	452	memset(&sin, 0, sizeof(sin));
	453	sin.sin_family = AF_INET;
	454	sin.sin_addr = io->io.bind;
	455	sin.sin_port = 0;
	456	if (bind(fd, (struct sockaddr *)&sin, sizeof(sin)))
	457	goto fail_1;
	458	}
	459	fdflags(fd, O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC);
	460	return (conn_init(c, sel, fd, (struct sockaddr *)&ia->sin, sizeof(ia->sin),
	461	starget_connected, e));
	462	fail_1:
	463	close(fd);
	464	fail_0:
	465	return (-1);
aa1f699e	466	}
	467
	468	/* --- Ops table --- */
	469
	470	addr_ops inet_ops = {
0ac54f22	471	"inet",
aa1f699e	472	inet_read, inet_destroy, inet_print,
ee599f55	473	inet_initsrcopts, inet_option, inet_confirm, inet_freesrcopts,
0ac54f22	474	inet_bind, 0, inet_accept,
	475	inet_inittargopts, inet_freetargopts,
	476	inet_connect
aa1f699e	477	};
	478
	479	/----- That's all, folks -------------------------------------------------/