| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: un.c,v 1.7 2003/11/29 20:36:07 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 1.7 2003/11/29 20:36:07 mdw |
| 33 | * Privileged outgoing connections. |
| 34 | * |
| 35 | * Revision 1.6 2003/11/25 14:08:23 mdw |
| 36 | * Debianization. Socket target options. Internet binding. |
| 37 | * |
| 38 | * Revision 1.5 2002/02/22 23:43:32 mdw |
| 39 | * Call @xfree@ rather than @free@. |
| 40 | * |
| 41 | * Revision 1.4 2000/08/01 17:59:56 mdw |
| 42 | * Switch over to using `size_t' for socket address lengths. |
| 43 | * |
| 44 | * Revision 1.3 2000/08/01 17:58:32 mdw |
| 45 | * Remove unnecessary <ctype.h> header. |
| 46 | * |
| 47 | * Revision 1.2 1999/07/27 18:30:53 mdw |
| 48 | * Various minor portability fixes. |
| 49 | * |
| 50 | * Revision 1.1 1999/07/26 23:34:11 mdw |
| 51 | * New socket address types. |
| 52 | * |
| 53 | */ |
| 54 | |
| 55 | /*----- Header files ------------------------------------------------------*/ |
| 56 | |
| 57 | #include "config.h" |
| 58 | #undef sun /* Cretins */ |
| 59 | |
| 60 | #include <errno.h> |
| 61 | #include <limits.h> |
| 62 | #include <stddef.h> |
| 63 | #include <stdio.h> |
| 64 | #include <stdlib.h> |
| 65 | #include <string.h> |
| 66 | |
| 67 | #include <sys/types.h> |
| 68 | #include <unistd.h> |
| 69 | |
| 70 | #include <sys/socket.h> |
| 71 | #include <sys/un.h> |
| 72 | #include <arpa/inet.h> |
| 73 | #include <netdb.h> |
| 74 | |
| 75 | #include <mLib/alloc.h> |
| 76 | #include <mLib/dstr.h> |
| 77 | #include <mLib/report.h> |
| 78 | #include <mLib/sub.h> |
| 79 | |
| 80 | #include "addr.h" |
| 81 | #include "conf.h" |
| 82 | #include "fattr.h" |
| 83 | #include "fw.h" |
| 84 | #include "reffd.h" |
| 85 | #include "scan.h" |
| 86 | #include "socket.h" |
| 87 | #include "un.h" |
| 88 | |
| 89 | /*----- Data structures ---------------------------------------------------*/ |
| 90 | |
| 91 | typedef struct un_addr { |
| 92 | addr a; |
| 93 | struct sockaddr_un sun; |
| 94 | } un_addr; |
| 95 | |
| 96 | typedef struct un_opts { |
| 97 | addr_opts ao; |
| 98 | fattr f; |
| 99 | } un_opts; |
| 100 | |
| 101 | /*----- Protocol operations -----------------------------------------------*/ |
| 102 | |
| 103 | /* --- @read@ --- */ |
| 104 | |
| 105 | static addr *un_read(scanner *sc, unsigned type) |
| 106 | { |
| 107 | dstr d = DSTR_INIT; |
| 108 | un_addr *ua; |
| 109 | |
| 110 | conf_name(sc, '/', &d); |
| 111 | ua = xmalloc(sizeof(addr) + |
| 112 | offsetof(struct sockaddr_un, sun_path) + |
| 113 | d.len + 1); |
| 114 | ua->a.ops = &un_ops; |
| 115 | ua->a.sz = offsetof(struct sockaddr_un, sun_path) + d.len + 1; |
| 116 | memset(&ua->sun, 0, ua->a.sz); |
| 117 | ua->sun.sun_family = AF_UNIX; |
| 118 | memcpy(ua->sun.sun_path, d.buf, d.len + 1); |
| 119 | dstr_destroy(&d); |
| 120 | return (&ua->a); |
| 121 | } |
| 122 | |
| 123 | /* --- @destroy@ --- */ |
| 124 | |
| 125 | static void un_destroy(addr *a) |
| 126 | { |
| 127 | un_addr *ua = (un_addr *)a; |
| 128 | xfree(ua); |
| 129 | } |
| 130 | |
| 131 | /* --- @print@ --- */ |
| 132 | |
| 133 | static void un_print(addr *a, unsigned type, dstr *d) |
| 134 | { |
| 135 | un_addr *ua = (un_addr *)a; |
| 136 | dstr_puts(d, "unix:"); |
| 137 | dstr_puts(d, ua->sun.sun_path); |
| 138 | } |
| 139 | |
| 140 | /* --- @initopts@ --- */ |
| 141 | |
| 142 | static addr_opts *un_initopts(void) |
| 143 | { |
| 144 | un_opts *uo = CREATE(un_opts); |
| 145 | uo->f = fattr_global; |
| 146 | return (&uo->ao); |
| 147 | } |
| 148 | |
| 149 | /* --- @option@ --- */ |
| 150 | |
| 151 | static int srcopt(scanner *sc, addr_opts *ao) |
| 152 | { |
| 153 | un_opts *uo = (un_opts *)ao; |
| 154 | CONF_BEGIN(sc, "unix", "Unix domain socket") |
| 155 | |
| 156 | if (fattr_option(sc, uo ? &uo->f : &fattr_global)) |
| 157 | CONF_ACCEPT; |
| 158 | |
| 159 | CONF_END; |
| 160 | } |
| 161 | |
| 162 | static int un_option(scanner *sc, addr_opts *ao, unsigned type) |
| 163 | { |
| 164 | CONF_BEGIN(sc, "unix", "Unix domain socket"); |
| 165 | if (type != ADDR_DEST && srcopt(sc, ao)) |
| 166 | CONF_ACCEPT; |
| 167 | CONF_END; |
| 168 | } |
| 169 | |
| 170 | /* --- @accept@ --- */ |
| 171 | |
| 172 | static reffd *un_accept(int fd, addr_opts *ao, const char *desc) |
| 173 | { |
| 174 | int nfd; |
| 175 | un_opts *uo = (un_opts *)ao; |
| 176 | |
| 177 | /* --- Accept the new connection --- */ |
| 178 | |
| 179 | { |
| 180 | char buf[PATH_MAX + sizeof(struct sockaddr)]; |
| 181 | struct sockaddr_un *sun = (struct sockaddr_un *)buf; |
| 182 | size_t sunsz = sizeof(buf); |
| 183 | |
| 184 | if ((nfd = accept(fd, (struct sockaddr *)sun, &sunsz)) < 0) |
| 185 | return (0); |
| 186 | } |
| 187 | |
| 188 | /* --- Log the connection --- * |
| 189 | * |
| 190 | * It'd be really nice if I could find out who the user is, but I can't in |
| 191 | * anything like a portable way. |
| 192 | */ |
| 193 | |
| 194 | if (!(uo->ao.f & ADDRF_NOLOG)) |
| 195 | fw_log(-1, "[%s] accepted", desc); |
| 196 | return (reffd_init(nfd)); |
| 197 | } |
| 198 | |
| 199 | /* --- @freeopts@ --- */ |
| 200 | |
| 201 | static void un_freeopts(addr_opts *ao) |
| 202 | { |
| 203 | un_opts *uo = (un_opts *)ao; |
| 204 | DESTROY(uo); |
| 205 | } |
| 206 | |
| 207 | /* --- @bind@ --- */ |
| 208 | |
| 209 | static int un_bind(addr *a, addr_opts *ao) |
| 210 | { |
| 211 | un_addr *ua = (un_addr *)a; |
| 212 | un_opts *uo = (un_opts *)ao; |
| 213 | int fd; |
| 214 | |
| 215 | if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) |
| 216 | goto fail_0; |
| 217 | if (bind(fd, (struct sockaddr *)&ua->sun, sizeof(ua->sun))) |
| 218 | goto fail_1; |
| 219 | if (fattr_apply(ua->sun.sun_path, &uo->f)) |
| 220 | goto fail_1; |
| 221 | return (fd); |
| 222 | |
| 223 | fail_1: |
| 224 | close(fd); |
| 225 | fail_0: |
| 226 | return (-1); |
| 227 | } |
| 228 | |
| 229 | /* --- @unbind@ --- */ |
| 230 | |
| 231 | static void un_unbind(addr *a) |
| 232 | { |
| 233 | un_addr *ua = (un_addr *)a; |
| 234 | unlink(ua->sun.sun_path); |
| 235 | } |
| 236 | |
| 237 | /* --- @connect@ --- */ |
| 238 | |
| 239 | static int un_connect(addr *a, addr_opts *ao, conn *c, endpt *e) |
| 240 | { |
| 241 | un_addr *ua = (un_addr *)a; |
| 242 | int fd; |
| 243 | |
| 244 | if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) |
| 245 | goto fail_0; |
| 246 | return (conn_init(c, sel, fd, (struct sockaddr *)&ua->sun, sizeof(ua->sun), |
| 247 | starget_connected, e)); |
| 248 | fail_0: |
| 249 | return (-1); |
| 250 | } |
| 251 | |
| 252 | /* --- Protocol definition --- */ |
| 253 | |
| 254 | addr_ops un_ops = { |
| 255 | "unix", |
| 256 | un_read, un_destroy, un_print, |
| 257 | un_initopts, un_option, 0, un_freeopts, un_bind, un_unbind, un_accept, |
| 258 | 0, 0, un_connect |
| 259 | }; |
| 260 | |
| 261 | /*----- That's all, folks -------------------------------------------------*/ |