mdw@git.distorted.org.uk Git - fwd/blob - un.c

   1 /* -*-c-*-
   2  *
   3  * $Id: un.c,v 1.6 2003/11/25 14:08:23 mdw Exp $
   4  *
   5  * Protocol specific definitions for Unix-domain sockets
   6  *
   7  * (c) 1999 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of the `fw' port forwarder.
  13  *
  14  * `fw' is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * `fw' is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with `fw'; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: un.c,v $
  32  * Revision 1.6  2003/11/25 14:08:23  mdw
  33  * Debianization.  Socket target options.  Internet binding.
  34  *
  35  * Revision 1.5  2002/02/22 23:43:32  mdw
  36  * Call @xfree@ rather than @free@.
  37  *
  38  * Revision 1.4  2000/08/01 17:59:56  mdw
  39  * Switch over to using `size_t' for socket address lengths.
  40  *
  41  * Revision 1.3  2000/08/01 17:58:32  mdw
  42  * Remove unnecessary <ctype.h> header.
  43  *
  44  * Revision 1.2  1999/07/27 18:30:53  mdw
  45  * Various minor portability fixes.
  46  *
  47  * Revision 1.1  1999/07/26 23:34:11  mdw
  48  * New socket address types.
  49  *
  50  */
  51
  52 /*----- Header files ------------------------------------------------------*/
  53
  54 #include "config.h"
  55 #undef sun /* Cretins */
  56
  57 #include <errno.h>
  58 #include <limits.h>
  59 #include <stddef.h>
  60 #include <stdio.h>
  61 #include <stdlib.h>
  62 #include <string.h>
  63
  64 #include <sys/types.h>
  65 #include <unistd.h>
  66
  67 #include <sys/socket.h>
  68 #include <sys/un.h>
  69 #include <arpa/inet.h>
  70 #include <netdb.h>
  71
  72 #include <mLib/alloc.h>
  73 #include <mLib/dstr.h>
  74 #include <mLib/report.h>
  75 #include <mLib/sub.h>
  76
  77 #include "addr.h"
  78 #include "conf.h"
  79 #include "fattr.h"
  80 #include "fw.h"
  81 #include "reffd.h"
  82 #include "scan.h"
  83 #include "socket.h"
  84 #include "un.h"
  85
  86 /*----- Data structures ---------------------------------------------------*/
  87
  88 typedef struct un_addr {
  89   addr a;
  90   struct sockaddr_un sun;
  91 } un_addr;
  92
  93 typedef struct un_opts {
  94   addr_opts ao;
  95   fattr f;
  96 } un_opts;
  97
  98 /*----- Protocol operations -----------------------------------------------*/
  99
 100 /* --- @read@ --- */
 101
 102 static addr *un_read(scanner *sc, unsigned type)
 103 {
 104   dstr d = DSTR_INIT;
 105   un_addr *ua;
 106
 107   conf_name(sc, '/', &d);
 108   ua = xmalloc(sizeof(addr) +
 109                offsetof(struct sockaddr_un, sun_path) +
 110                d.len + 1);
 111   ua->a.ops = &un_ops;
 112   ua->a.sz = offsetof(struct sockaddr_un, sun_path) + d.len + 1;
 113   memset(&ua->sun, 0, ua->a.sz);
 114   ua->sun.sun_family = AF_UNIX;
 115   memcpy(ua->sun.sun_path, d.buf, d.len + 1);
 116   dstr_destroy(&d);
 117   return (&ua->a);
 118 }
 119
 120 /* --- @destroy@ --- */
 121
 122 static void un_destroy(addr *a)
 123 {
 124   un_addr *ua = (un_addr *)a;
 125   xfree(ua);
 126 }
 127
 128 /* --- @print@ --- */
 129
 130 static void un_print(addr *a, unsigned type, dstr *d)
 131 {
 132   un_addr *ua = (un_addr *)a;
 133   dstr_puts(d, "unix:");
 134   dstr_puts(d, ua->sun.sun_path);
 135 }
 136
 137 /* --- @initopts@ --- */
 138
 139 static addr_opts *un_initopts(void)
 140 {
 141   un_opts *uo = CREATE(un_opts);
 142   uo->f = fattr_global;
 143   return (&uo->ao);
 144 }
 145
 146 /* --- @option@ --- */
 147
 148 static int srcopt(scanner *sc, addr_opts *ao)
 149 {
 150   un_opts *uo = (un_opts *)ao;
 151   CONF_BEGIN(sc, "unix", "Unix domain socket")
 152
 153   if (fattr_option(sc, uo ? &uo->f : &fattr_global))
 154     CONF_ACCEPT;
 155
 156   CONF_END;
 157 }
 158
 159 static int un_option(scanner *sc, addr_opts *ao, unsigned type)
 160 {
 161   CONF_BEGIN(sc, "unix", "Unix domain socket");
 162   if (type != ADDR_DEST && srcopt(sc, ao))
 163     CONF_ACCEPT;
 164   CONF_END;
 165 }
 166
 167 /* --- @accept@ --- */
 168
 169 static reffd *un_accept(int fd, addr_opts *ao, const char *desc)
 170 {
 171   int nfd;
 172   un_opts *uo = (un_opts *)ao;
 173
 174   /* --- Accept the new connection --- */
 175
 176   {
 177     char buf[PATH_MAX + sizeof(struct sockaddr)];
 178     struct sockaddr_un *sun = (struct sockaddr_un *)buf;
 179     size_t sunsz = sizeof(buf);
 180
 181     if ((nfd = accept(fd, (struct sockaddr *)sun, &sunsz)) < 0)
 182       return (0);
 183   }
 184
 185   /* --- Log the connection --- *
 186    *
 187    * It'd be really nice if I could find out who the user is, but I can't in
 188    * anything like a portable way.
 189    */
 190
 191   if (!(uo->ao.f & ADDRF_NOLOG))
 192     fw_log(-1, "[%s] accepted", desc);
 193   return (reffd_init(nfd));
 194 }
 195
 196 /* --- @freeopts@ --- */
 197
 198 static void un_freeopts(addr_opts *ao)
 199 {
 200   un_opts *uo = (un_opts *)ao;
 201   DESTROY(uo);
 202 }
 203
 204 /* --- @bind@ --- */
 205
 206 static int un_bind(addr *a, addr_opts *ao)
 207 {
 208   un_addr *ua = (un_addr *)a;
 209   un_opts *uo = (un_opts *)ao;
 210   int fd;
 211
 212   if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
 213     goto fail_0;
 214   if (bind(fd, (struct sockaddr *)&ua->sun, sizeof(ua->sun)))
 215     goto fail_1;
 216   if (fattr_apply(ua->sun.sun_path, &uo->f))
 217     goto fail_1;
 218   return (fd);
 219
 220 fail_1:
 221   close(fd);
 222 fail_0:
 223   return (-1);
 224 }
 225
 226 /* --- @unbind@ --- */
 227
 228 static void un_unbind(addr *a)
 229 {
 230   un_addr *ua = (un_addr *)a;
 231   unlink(ua->sun.sun_path);
 232 }
 233
 234 /* --- @connect@ --- */
 235
 236 static int un_connect(addr *a, addr_opts *ao, conn *c, endpt *e)
 237 {
 238   un_addr *ua = (un_addr *)a;
 239   int fd;
 240
 241   if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
 242     goto fail_0;
 243   return (conn_init(c, sel, fd, (struct sockaddr *)&ua->sun, sizeof(ua->sun),
 244                     starget_connected, e));
 245 fail_0:
 246   return (-1);
 247 }
 248
 249 /* --- Protocol definition --- */
 250
 251 addr_ops un_ops = {
 252   "unix",
 253   un_read, un_destroy, un_print,
 254   un_initopts, un_option, un_freeopts, un_bind, un_unbind, un_accept,
 255   0, 0, un_connect
 256 };
 257
 258 /*----- That's all, folks -------------------------------------------------*/