uipc_accf.c revision 1.2.2.2
1 1.2.2.2 wrstuden /*- 2 1.2.2.2 wrstuden * Copyright (c) 2000 Paycounter, Inc. 3 1.2.2.2 wrstuden * Copyright (c) 2005 Robert N. M. Watson 4 1.2.2.2 wrstuden * Author: Alfred Perlstein <alfred (at) paycounter.com>, <alfred (at) FreeBSD.org> 5 1.2.2.2 wrstuden * All rights reserved. 6 1.2.2.2 wrstuden * 7 1.2.2.2 wrstuden * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 wrstuden * modification, are permitted provided that the following conditions 9 1.2.2.2 wrstuden * are met: 10 1.2.2.2 wrstuden * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 wrstuden * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 wrstuden * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 wrstuden * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 wrstuden * documentation and/or other materials provided with the distribution. 15 1.2.2.2 wrstuden * 16 1.2.2.2 wrstuden * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 1.2.2.2 wrstuden * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 1.2.2.2 wrstuden * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 1.2.2.2 wrstuden * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 1.2.2.2 wrstuden * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 1.2.2.2 wrstuden * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 1.2.2.2 wrstuden * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 1.2.2.2 wrstuden * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 1.2.2.2 wrstuden * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 1.2.2.2 wrstuden * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 1.2.2.2 wrstuden * SUCH DAMAGE. 27 1.2.2.2 wrstuden */ 28 1.2.2.2 wrstuden 29 1.2.2.2 wrstuden #include <sys/cdefs.h> 30 1.2.2.2 wrstuden __KERNEL_RCSID(0, "$NetBSD: uipc_accf.c,v 1.2.2.2 2008/09/18 04:31:44 wrstuden Exp $"); 31 1.2.2.2 wrstuden 32 1.2.2.2 wrstuden #define ACCEPT_FILTER_MOD 33 1.2.2.2 wrstuden 34 1.2.2.2 wrstuden #include "opt_inet.h" 35 1.2.2.2 wrstuden #include <sys/param.h> 36 1.2.2.2 wrstuden #include <sys/systm.h> 37 1.2.2.2 wrstuden #include <sys/domain.h> 38 1.2.2.2 wrstuden #include <sys/kernel.h> 39 1.2.2.2 wrstuden #include <sys/lock.h> 40 1.2.2.2 wrstuden #include <sys/malloc.h> 41 1.2.2.2 wrstuden #include <sys/mbuf.h> 42 1.2.2.2 wrstuden #include <sys/lkm.h> 43 1.2.2.2 wrstuden #include <sys/mutex.h> 44 1.2.2.2 wrstuden #include <sys/protosw.h> 45 1.2.2.2 wrstuden #include <sys/sysctl.h> 46 1.2.2.2 wrstuden #include <sys/socket.h> 47 1.2.2.2 wrstuden #include <sys/socketvar.h> 48 1.2.2.2 wrstuden #include <sys/queue.h> 49 1.2.2.2 wrstuden #include <sys/once.h> 50 1.2.2.2 wrstuden 51 1.2.2.2 wrstuden static kmutex_t accept_filter_mtx; 52 1.2.2.2 wrstuden #define ACCEPT_FILTER_LOCK() mutex_spin_enter(&accept_filter_mtx) 53 1.2.2.2 wrstuden #define ACCEPT_FILTER_UNLOCK() mutex_spin_exit(&accept_filter_mtx); 54 1.2.2.2 wrstuden #define SOCK_LOCK(so) 55 1.2.2.2 wrstuden #define SOCK_UNLOCK(so) 56 1.2.2.2 wrstuden 57 1.2.2.2 wrstuden static SLIST_HEAD(, accept_filter) accept_filtlsthd = 58 1.2.2.2 wrstuden SLIST_HEAD_INITIALIZER(&accept_filtlsthd); 59 1.2.2.2 wrstuden 60 1.2.2.2 wrstuden MALLOC_DEFINE(M_ACCF, "accf", "accept filter data"); 61 1.2.2.2 wrstuden 62 1.2.2.2 wrstuden static int unloadable = 0; 63 1.2.2.2 wrstuden 64 1.2.2.2 wrstuden /* 65 1.2.2.2 wrstuden * Names of Accept filter sysctl objects 66 1.2.2.2 wrstuden */ 67 1.2.2.2 wrstuden 68 1.2.2.2 wrstuden #define ACCFCTL_UNLOADABLE 1 /* Allow module to be unloaded */ 69 1.2.2.2 wrstuden 70 1.2.2.2 wrstuden 71 1.2.2.2 wrstuden SYSCTL_SETUP(sysctl_net_inet_accf_setup, "sysctl net.inet.accf subtree setup") 72 1.2.2.2 wrstuden { 73 1.2.2.2 wrstuden sysctl_createv(clog, 0, NULL, NULL, 74 1.2.2.2 wrstuden CTLFLAG_PERMANENT, 75 1.2.2.2 wrstuden CTLTYPE_NODE, "net", NULL, 76 1.2.2.2 wrstuden NULL, 0, NULL, 0, 77 1.2.2.2 wrstuden CTL_NET, CTL_EOL); 78 1.2.2.2 wrstuden sysctl_createv(clog, 0, NULL, NULL, 79 1.2.2.2 wrstuden CTLFLAG_PERMANENT, 80 1.2.2.2 wrstuden CTLTYPE_NODE, "inet", NULL, 81 1.2.2.2 wrstuden NULL, 0, NULL, 0, 82 1.2.2.2 wrstuden CTL_NET, PF_INET, CTL_EOL); 83 1.2.2.2 wrstuden sysctl_createv(clog, 0, NULL, NULL, 84 1.2.2.2 wrstuden CTLFLAG_PERMANENT, 85 1.2.2.2 wrstuden CTLTYPE_NODE, "accf", 86 1.2.2.2 wrstuden SYSCTL_DESCR("Accept filters"), 87 1.2.2.2 wrstuden NULL, 0, NULL, 0, 88 1.2.2.2 wrstuden CTL_NET, PF_INET, SO_ACCEPTFILTER, CTL_EOL); 89 1.2.2.2 wrstuden sysctl_createv(clog, 0, NULL, NULL, 90 1.2.2.2 wrstuden CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 91 1.2.2.2 wrstuden CTLTYPE_INT, "unloadable", 92 1.2.2.2 wrstuden SYSCTL_DESCR("Allow unload of accept filters " 93 1.2.2.2 wrstuden "(not recommended)"), 94 1.2.2.2 wrstuden NULL, 0, &unloadable, 0, 95 1.2.2.2 wrstuden CTL_NET, PF_INET, SO_ACCEPTFILTER, 96 1.2.2.2 wrstuden ACCFCTL_UNLOADABLE, CTL_EOL); 97 1.2.2.2 wrstuden } 98 1.2.2.2 wrstuden 99 1.2.2.2 wrstuden /* 100 1.2.2.2 wrstuden * Must be passed a malloc'd structure so we don't explode if the kld is 101 1.2.2.2 wrstuden * unloaded, we leak the struct on deallocation to deal with this, but if a 102 1.2.2.2 wrstuden * filter is loaded with the same name as a leaked one we re-use the entry. 103 1.2.2.2 wrstuden */ 104 1.2.2.2 wrstuden int 105 1.2.2.2 wrstuden accept_filt_add(struct accept_filter *filt) 106 1.2.2.2 wrstuden { 107 1.2.2.2 wrstuden struct accept_filter *p; 108 1.2.2.2 wrstuden 109 1.2.2.2 wrstuden ACCEPT_FILTER_LOCK(); 110 1.2.2.2 wrstuden SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 111 1.2.2.2 wrstuden if (strcmp(p->accf_name, filt->accf_name) == 0) { 112 1.2.2.2 wrstuden if (p->accf_callback != NULL) { 113 1.2.2.2 wrstuden ACCEPT_FILTER_UNLOCK(); 114 1.2.2.2 wrstuden return (EEXIST); 115 1.2.2.2 wrstuden } else { 116 1.2.2.2 wrstuden p->accf_callback = filt->accf_callback; 117 1.2.2.2 wrstuden ACCEPT_FILTER_UNLOCK(); 118 1.2.2.2 wrstuden FREE(filt, M_ACCF); 119 1.2.2.2 wrstuden return (0); 120 1.2.2.2 wrstuden } 121 1.2.2.2 wrstuden } 122 1.2.2.2 wrstuden 123 1.2.2.2 wrstuden if (p == NULL) 124 1.2.2.2 wrstuden SLIST_INSERT_HEAD(&accept_filtlsthd, filt, accf_next); 125 1.2.2.2 wrstuden ACCEPT_FILTER_UNLOCK(); 126 1.2.2.2 wrstuden return (0); 127 1.2.2.2 wrstuden } 128 1.2.2.2 wrstuden 129 1.2.2.2 wrstuden int 130 1.2.2.2 wrstuden accept_filt_del(char *name) 131 1.2.2.2 wrstuden { 132 1.2.2.2 wrstuden struct accept_filter *p; 133 1.2.2.2 wrstuden 134 1.2.2.2 wrstuden p = accept_filt_get(name); 135 1.2.2.2 wrstuden if (p == NULL) 136 1.2.2.2 wrstuden return (ENOENT); 137 1.2.2.2 wrstuden 138 1.2.2.2 wrstuden p->accf_callback = NULL; 139 1.2.2.2 wrstuden return (0); 140 1.2.2.2 wrstuden } 141 1.2.2.2 wrstuden 142 1.2.2.2 wrstuden struct accept_filter * 143 1.2.2.2 wrstuden accept_filt_get(char *name) 144 1.2.2.2 wrstuden { 145 1.2.2.2 wrstuden struct accept_filter *p; 146 1.2.2.2 wrstuden 147 1.2.2.2 wrstuden ACCEPT_FILTER_LOCK(); 148 1.2.2.2 wrstuden SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 149 1.2.2.2 wrstuden if (strcmp(p->accf_name, name) == 0) 150 1.2.2.2 wrstuden break; 151 1.2.2.2 wrstuden ACCEPT_FILTER_UNLOCK(); 152 1.2.2.2 wrstuden 153 1.2.2.2 wrstuden return (p); 154 1.2.2.2 wrstuden } 155 1.2.2.2 wrstuden 156 1.2.2.2 wrstuden /* 157 1.2.2.2 wrstuden * Accept filter initialization routine. 158 1.2.2.2 wrstuden * This should be called only once. 159 1.2.2.2 wrstuden */ 160 1.2.2.2 wrstuden 161 1.2.2.2 wrstuden static int 162 1.2.2.2 wrstuden accept_filter_init0(void) 163 1.2.2.2 wrstuden { 164 1.2.2.2 wrstuden mutex_init(&accept_filter_mtx, MUTEX_DEFAULT, IPL_NET); 165 1.2.2.2 wrstuden 166 1.2.2.2 wrstuden return 0; 167 1.2.2.2 wrstuden } 168 1.2.2.2 wrstuden 169 1.2.2.2 wrstuden /* 170 1.2.2.2 wrstuden * Initialization routine: This can also be replaced with 171 1.2.2.2 wrstuden * accept_filt_generic_mod_event for attaching new accept filter. 172 1.2.2.2 wrstuden */ 173 1.2.2.2 wrstuden 174 1.2.2.2 wrstuden void 175 1.2.2.2 wrstuden accept_filter_init(void) 176 1.2.2.2 wrstuden { 177 1.2.2.2 wrstuden static ONCE_DECL(accept_filter_init_once); 178 1.2.2.2 wrstuden 179 1.2.2.2 wrstuden RUN_ONCE(&accept_filter_init_once, accept_filter_init0); 180 1.2.2.2 wrstuden } 181 1.2.2.2 wrstuden 182 1.2.2.2 wrstuden int 183 1.2.2.2 wrstuden accept_filt_generic_mod_event(struct lkm_table *lkmtp, int event, void *data) 184 1.2.2.2 wrstuden { 185 1.2.2.2 wrstuden struct accept_filter *p; 186 1.2.2.2 wrstuden struct accept_filter *accfp = (struct accept_filter *) data; 187 1.2.2.2 wrstuden int error; 188 1.2.2.2 wrstuden 189 1.2.2.2 wrstuden switch (event) { 190 1.2.2.2 wrstuden case LKM_E_LOAD: 191 1.2.2.2 wrstuden accept_filter_init(); 192 1.2.2.2 wrstuden MALLOC(p, struct accept_filter *, sizeof(*p), M_ACCF, 193 1.2.2.2 wrstuden M_WAITOK); 194 1.2.2.2 wrstuden bcopy(accfp, p, sizeof(*p)); 195 1.2.2.2 wrstuden error = accept_filt_add(p); 196 1.2.2.2 wrstuden break; 197 1.2.2.2 wrstuden 198 1.2.2.2 wrstuden case LKM_E_UNLOAD: 199 1.2.2.2 wrstuden /* 200 1.2.2.2 wrstuden * Do not support unloading yet. we don't keep track of 201 1.2.2.2 wrstuden * refcounts and unloading an accept filter callback and then 202 1.2.2.2 wrstuden * having it called is a bad thing. A simple fix would be to 203 1.2.2.2 wrstuden * track the refcount in the struct accept_filter. 204 1.2.2.2 wrstuden */ 205 1.2.2.2 wrstuden if (unloadable != 0) { 206 1.2.2.2 wrstuden error = accept_filt_del(accfp->accf_name); 207 1.2.2.2 wrstuden } else 208 1.2.2.2 wrstuden error = EOPNOTSUPP; 209 1.2.2.2 wrstuden break; 210 1.2.2.2 wrstuden 211 1.2.2.2 wrstuden case LKM_E_STAT: 212 1.2.2.2 wrstuden error = 0; 213 1.2.2.2 wrstuden break; 214 1.2.2.2 wrstuden 215 1.2.2.2 wrstuden default: 216 1.2.2.2 wrstuden error = EOPNOTSUPP; 217 1.2.2.2 wrstuden break; 218 1.2.2.2 wrstuden } 219 1.2.2.2 wrstuden 220 1.2.2.2 wrstuden return (error); 221 1.2.2.2 wrstuden } 222 1.2.2.2 wrstuden 223 1.2.2.2 wrstuden int 224 1.2.2.2 wrstuden do_getopt_accept_filter(struct socket *so, struct sockopt *sopt) 225 1.2.2.2 wrstuden { 226 1.2.2.2 wrstuden struct accept_filter_arg afa; 227 1.2.2.2 wrstuden int error; 228 1.2.2.2 wrstuden 229 1.2.2.2 wrstuden SOCK_LOCK(so); 230 1.2.2.2 wrstuden if ((so->so_options & SO_ACCEPTCONN) == 0) { 231 1.2.2.2 wrstuden error = EINVAL; 232 1.2.2.2 wrstuden goto out; 233 1.2.2.2 wrstuden } 234 1.2.2.2 wrstuden if ((so->so_options & SO_ACCEPTFILTER) == 0) { 235 1.2.2.2 wrstuden error = EINVAL; 236 1.2.2.2 wrstuden goto out; 237 1.2.2.2 wrstuden } 238 1.2.2.2 wrstuden 239 1.2.2.2 wrstuden memset(&afa, 0, sizeof(afa)); 240 1.2.2.2 wrstuden strcpy(afa.af_name, so->so_accf->so_accept_filter->accf_name); 241 1.2.2.2 wrstuden if (so->so_accf->so_accept_filter_str != NULL) 242 1.2.2.2 wrstuden strcpy(afa.af_arg, so->so_accf->so_accept_filter_str); 243 1.2.2.2 wrstuden error = sockopt_set(sopt, &afa, sizeof(afa)); 244 1.2.2.2 wrstuden out: 245 1.2.2.2 wrstuden SOCK_UNLOCK(so); 246 1.2.2.2 wrstuden return (error); 247 1.2.2.2 wrstuden } 248 1.2.2.2 wrstuden 249 1.2.2.2 wrstuden int 250 1.2.2.2 wrstuden do_setopt_accept_filter(struct socket *so, const struct sockopt *sopt) 251 1.2.2.2 wrstuden { 252 1.2.2.2 wrstuden struct accept_filter_arg afa; 253 1.2.2.2 wrstuden struct accept_filter *afp; 254 1.2.2.2 wrstuden struct so_accf *newaf; 255 1.2.2.2 wrstuden int error; 256 1.2.2.2 wrstuden 257 1.2.2.2 wrstuden /* 258 1.2.2.2 wrstuden * Handle the simple delete case first. 259 1.2.2.2 wrstuden */ 260 1.2.2.2 wrstuden if (sopt == NULL || sopt->sopt_size == 0) { 261 1.2.2.2 wrstuden SOCK_LOCK(so); 262 1.2.2.2 wrstuden if ((so->so_options & SO_ACCEPTCONN) == 0) { 263 1.2.2.2 wrstuden SOCK_UNLOCK(so); 264 1.2.2.2 wrstuden return (EINVAL); 265 1.2.2.2 wrstuden } 266 1.2.2.2 wrstuden if (so->so_accf != NULL) { 267 1.2.2.2 wrstuden struct so_accf *af = so->so_accf; 268 1.2.2.2 wrstuden if (af->so_accept_filter != NULL && 269 1.2.2.2 wrstuden af->so_accept_filter->accf_destroy != NULL) { 270 1.2.2.2 wrstuden af->so_accept_filter->accf_destroy(so); 271 1.2.2.2 wrstuden } 272 1.2.2.2 wrstuden if (af->so_accept_filter_str != NULL) 273 1.2.2.2 wrstuden FREE(af->so_accept_filter_str, M_ACCF); 274 1.2.2.2 wrstuden FREE(af, M_ACCF); 275 1.2.2.2 wrstuden so->so_accf = NULL; 276 1.2.2.2 wrstuden } 277 1.2.2.2 wrstuden so->so_options &= ~SO_ACCEPTFILTER; 278 1.2.2.2 wrstuden SOCK_UNLOCK(so); 279 1.2.2.2 wrstuden return (0); 280 1.2.2.2 wrstuden } 281 1.2.2.2 wrstuden 282 1.2.2.2 wrstuden /* 283 1.2.2.2 wrstuden * Pre-allocate any memory we may need later to avoid blocking at 284 1.2.2.2 wrstuden * untimely moments. This does not optimize for invalid arguments. 285 1.2.2.2 wrstuden */ 286 1.2.2.2 wrstuden error = sockopt_get(sopt, &afa, sizeof(afa)); 287 1.2.2.2 wrstuden if (error) { 288 1.2.2.2 wrstuden return (error); 289 1.2.2.2 wrstuden } 290 1.2.2.2 wrstuden afa.af_name[sizeof(afa.af_name)-1] = '\0'; 291 1.2.2.2 wrstuden afa.af_arg[sizeof(afa.af_arg)-1] = '\0'; 292 1.2.2.2 wrstuden afp = accept_filt_get(afa.af_name); 293 1.2.2.2 wrstuden if (afp == NULL) { 294 1.2.2.2 wrstuden return (ENOENT); 295 1.2.2.2 wrstuden } 296 1.2.2.2 wrstuden /* 297 1.2.2.2 wrstuden * Allocate the new accept filter instance storage. We may 298 1.2.2.2 wrstuden * have to free it again later if we fail to attach it. If 299 1.2.2.2 wrstuden * attached properly, 'newaf' is NULLed to avoid a free() 300 1.2.2.2 wrstuden * while in use. 301 1.2.2.2 wrstuden */ 302 1.2.2.2 wrstuden MALLOC(newaf, struct so_accf *, sizeof(*newaf), M_ACCF, M_WAITOK | 303 1.2.2.2 wrstuden M_ZERO); 304 1.2.2.2 wrstuden if (afp->accf_create != NULL && afa.af_name[0] != '\0') { 305 1.2.2.2 wrstuden int len = strlen(afa.af_name) + 1; 306 1.2.2.2 wrstuden MALLOC(newaf->so_accept_filter_str, char *, len, M_ACCF, 307 1.2.2.2 wrstuden M_WAITOK); 308 1.2.2.2 wrstuden strcpy(newaf->so_accept_filter_str, afa.af_name); 309 1.2.2.2 wrstuden } 310 1.2.2.2 wrstuden 311 1.2.2.2 wrstuden /* 312 1.2.2.2 wrstuden * Require a listen socket; don't try to replace an existing filter 313 1.2.2.2 wrstuden * without first removing it. 314 1.2.2.2 wrstuden */ 315 1.2.2.2 wrstuden SOCK_LOCK(so); 316 1.2.2.2 wrstuden if (((so->so_options & SO_ACCEPTCONN) == 0) || 317 1.2.2.2 wrstuden (so->so_accf != NULL)) { 318 1.2.2.2 wrstuden error = EINVAL; 319 1.2.2.2 wrstuden goto out; 320 1.2.2.2 wrstuden } 321 1.2.2.2 wrstuden 322 1.2.2.2 wrstuden /* 323 1.2.2.2 wrstuden * Invoke the accf_create() method of the filter if required. The 324 1.2.2.2 wrstuden * socket mutex is held over this call, so create methods for filters 325 1.2.2.2 wrstuden * can't block. 326 1.2.2.2 wrstuden */ 327 1.2.2.2 wrstuden if (afp->accf_create != NULL) { 328 1.2.2.2 wrstuden newaf->so_accept_filter_arg = 329 1.2.2.2 wrstuden afp->accf_create(so, afa.af_arg); 330 1.2.2.2 wrstuden if (newaf->so_accept_filter_arg == NULL) { 331 1.2.2.2 wrstuden error = EINVAL; 332 1.2.2.2 wrstuden goto out; 333 1.2.2.2 wrstuden } 334 1.2.2.2 wrstuden } 335 1.2.2.2 wrstuden newaf->so_accept_filter = afp; 336 1.2.2.2 wrstuden so->so_accf = newaf; 337 1.2.2.2 wrstuden so->so_options |= SO_ACCEPTFILTER; 338 1.2.2.2 wrstuden newaf = NULL; 339 1.2.2.2 wrstuden out: 340 1.2.2.2 wrstuden SOCK_UNLOCK(so); 341 1.2.2.2 wrstuden if (newaf != NULL) { 342 1.2.2.2 wrstuden if (newaf->so_accept_filter_str != NULL) 343 1.2.2.2 wrstuden FREE(newaf->so_accept_filter_str, M_ACCF); 344 1.2.2.2 wrstuden FREE(newaf, M_ACCF); 345 1.2.2.2 wrstuden } 346 1.2.2.2 wrstuden return (error); 347 1.2.2.2 wrstuden } 348
Indexes created Tue Oct 14 01:09:49 GMT 2025