uipc_accf.c revision 1.3.2.2
1 1.3.2.2 mjf /*- 2 1.3.2.2 mjf * Copyright (c) 2000 Paycounter, Inc. 3 1.3.2.2 mjf * Copyright (c) 2005 Robert N. M. Watson 4 1.3.2.2 mjf * Author: Alfred Perlstein <alfred (at) paycounter.com>, <alfred (at) FreeBSD.org> 5 1.3.2.2 mjf * All rights reserved. 6 1.3.2.2 mjf * 7 1.3.2.2 mjf * Redistribution and use in source and binary forms, with or without 8 1.3.2.2 mjf * modification, are permitted provided that the following conditions 9 1.3.2.2 mjf * are met: 10 1.3.2.2 mjf * 1. Redistributions of source code must retain the above copyright 11 1.3.2.2 mjf * notice, this list of conditions and the following disclaimer. 12 1.3.2.2 mjf * 2. Redistributions in binary form must reproduce the above copyright 13 1.3.2.2 mjf * notice, this list of conditions and the following disclaimer in the 14 1.3.2.2 mjf * documentation and/or other materials provided with the distribution. 15 1.3.2.2 mjf * 16 1.3.2.2 mjf * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 1.3.2.2 mjf * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 1.3.2.2 mjf * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 1.3.2.2 mjf * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 1.3.2.2 mjf * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 1.3.2.2 mjf * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 1.3.2.2 mjf * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 1.3.2.2 mjf * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 1.3.2.2 mjf * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 1.3.2.2 mjf * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 1.3.2.2 mjf * SUCH DAMAGE. 27 1.3.2.2 mjf */ 28 1.3.2.2 mjf 29 1.3.2.2 mjf #include <sys/cdefs.h> 30 1.3.2.2 mjf __KERNEL_RCSID(0, "$NetBSD: uipc_accf.c,v 1.3.2.2 2008/09/28 10:40:54 mjf Exp $"); 31 1.3.2.2 mjf 32 1.3.2.2 mjf #define ACCEPT_FILTER_MOD 33 1.3.2.2 mjf 34 1.3.2.2 mjf #include "opt_inet.h" 35 1.3.2.2 mjf #include <sys/param.h> 36 1.3.2.2 mjf #include <sys/systm.h> 37 1.3.2.2 mjf #include <sys/domain.h> 38 1.3.2.2 mjf #include <sys/kernel.h> 39 1.3.2.2 mjf #include <sys/lock.h> 40 1.3.2.2 mjf #include <sys/malloc.h> 41 1.3.2.2 mjf #include <sys/mbuf.h> 42 1.3.2.2 mjf #include <sys/lkm.h> 43 1.3.2.2 mjf #include <sys/mutex.h> 44 1.3.2.2 mjf #include <sys/protosw.h> 45 1.3.2.2 mjf #include <sys/sysctl.h> 46 1.3.2.2 mjf #include <sys/socket.h> 47 1.3.2.2 mjf #include <sys/socketvar.h> 48 1.3.2.2 mjf #include <sys/queue.h> 49 1.3.2.2 mjf #include <sys/once.h> 50 1.3.2.2 mjf 51 1.3.2.2 mjf static kmutex_t accept_filter_mtx; 52 1.3.2.2 mjf #define ACCEPT_FILTER_LOCK() mutex_spin_enter(&accept_filter_mtx) 53 1.3.2.2 mjf #define ACCEPT_FILTER_UNLOCK() mutex_spin_exit(&accept_filter_mtx); 54 1.3.2.2 mjf #define SOCK_LOCK(so) 55 1.3.2.2 mjf #define SOCK_UNLOCK(so) 56 1.3.2.2 mjf 57 1.3.2.2 mjf static SLIST_HEAD(, accept_filter) accept_filtlsthd = 58 1.3.2.2 mjf SLIST_HEAD_INITIALIZER(&accept_filtlsthd); 59 1.3.2.2 mjf 60 1.3.2.2 mjf MALLOC_DEFINE(M_ACCF, "accf", "accept filter data"); 61 1.3.2.2 mjf 62 1.3.2.2 mjf static int unloadable = 0; 63 1.3.2.2 mjf 64 1.3.2.2 mjf /* 65 1.3.2.2 mjf * Names of Accept filter sysctl objects 66 1.3.2.2 mjf */ 67 1.3.2.2 mjf 68 1.3.2.2 mjf #define ACCFCTL_UNLOADABLE 1 /* Allow module to be unloaded */ 69 1.3.2.2 mjf 70 1.3.2.2 mjf 71 1.3.2.2 mjf SYSCTL_SETUP(sysctl_net_inet_accf_setup, "sysctl net.inet.accf subtree setup") 72 1.3.2.2 mjf { 73 1.3.2.2 mjf sysctl_createv(clog, 0, NULL, NULL, 74 1.3.2.2 mjf CTLFLAG_PERMANENT, 75 1.3.2.2 mjf CTLTYPE_NODE, "net", NULL, 76 1.3.2.2 mjf NULL, 0, NULL, 0, 77 1.3.2.2 mjf CTL_NET, CTL_EOL); 78 1.3.2.2 mjf sysctl_createv(clog, 0, NULL, NULL, 79 1.3.2.2 mjf CTLFLAG_PERMANENT, 80 1.3.2.2 mjf CTLTYPE_NODE, "inet", NULL, 81 1.3.2.2 mjf NULL, 0, NULL, 0, 82 1.3.2.2 mjf CTL_NET, PF_INET, CTL_EOL); 83 1.3.2.2 mjf sysctl_createv(clog, 0, NULL, NULL, 84 1.3.2.2 mjf CTLFLAG_PERMANENT, 85 1.3.2.2 mjf CTLTYPE_NODE, "accf", 86 1.3.2.2 mjf SYSCTL_DESCR("Accept filters"), 87 1.3.2.2 mjf NULL, 0, NULL, 0, 88 1.3.2.2 mjf CTL_NET, PF_INET, SO_ACCEPTFILTER, CTL_EOL); 89 1.3.2.2 mjf sysctl_createv(clog, 0, NULL, NULL, 90 1.3.2.2 mjf CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 91 1.3.2.2 mjf CTLTYPE_INT, "unloadable", 92 1.3.2.2 mjf SYSCTL_DESCR("Allow unload of accept filters " 93 1.3.2.2 mjf "(not recommended)"), 94 1.3.2.2 mjf NULL, 0, &unloadable, 0, 95 1.3.2.2 mjf CTL_NET, PF_INET, SO_ACCEPTFILTER, 96 1.3.2.2 mjf ACCFCTL_UNLOADABLE, CTL_EOL); 97 1.3.2.2 mjf } 98 1.3.2.2 mjf 99 1.3.2.2 mjf /* 100 1.3.2.2 mjf * Must be passed a malloc'd structure so we don't explode if the kld is 101 1.3.2.2 mjf * unloaded, we leak the struct on deallocation to deal with this, but if a 102 1.3.2.2 mjf * filter is loaded with the same name as a leaked one we re-use the entry. 103 1.3.2.2 mjf */ 104 1.3.2.2 mjf int 105 1.3.2.2 mjf accept_filt_add(struct accept_filter *filt) 106 1.3.2.2 mjf { 107 1.3.2.2 mjf struct accept_filter *p; 108 1.3.2.2 mjf 109 1.3.2.2 mjf ACCEPT_FILTER_LOCK(); 110 1.3.2.2 mjf SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 111 1.3.2.2 mjf if (strcmp(p->accf_name, filt->accf_name) == 0) { 112 1.3.2.2 mjf if (p->accf_callback != NULL) { 113 1.3.2.2 mjf ACCEPT_FILTER_UNLOCK(); 114 1.3.2.2 mjf return (EEXIST); 115 1.3.2.2 mjf } else { 116 1.3.2.2 mjf p->accf_callback = filt->accf_callback; 117 1.3.2.2 mjf ACCEPT_FILTER_UNLOCK(); 118 1.3.2.2 mjf FREE(filt, M_ACCF); 119 1.3.2.2 mjf return (0); 120 1.3.2.2 mjf } 121 1.3.2.2 mjf } 122 1.3.2.2 mjf 123 1.3.2.2 mjf if (p == NULL) 124 1.3.2.2 mjf SLIST_INSERT_HEAD(&accept_filtlsthd, filt, accf_next); 125 1.3.2.2 mjf ACCEPT_FILTER_UNLOCK(); 126 1.3.2.2 mjf return (0); 127 1.3.2.2 mjf } 128 1.3.2.2 mjf 129 1.3.2.2 mjf int 130 1.3.2.2 mjf accept_filt_del(char *name) 131 1.3.2.2 mjf { 132 1.3.2.2 mjf struct accept_filter *p; 133 1.3.2.2 mjf 134 1.3.2.2 mjf p = accept_filt_get(name); 135 1.3.2.2 mjf if (p == NULL) 136 1.3.2.2 mjf return (ENOENT); 137 1.3.2.2 mjf 138 1.3.2.2 mjf p->accf_callback = NULL; 139 1.3.2.2 mjf return (0); 140 1.3.2.2 mjf } 141 1.3.2.2 mjf 142 1.3.2.2 mjf struct accept_filter * 143 1.3.2.2 mjf accept_filt_get(char *name) 144 1.3.2.2 mjf { 145 1.3.2.2 mjf struct accept_filter *p; 146 1.3.2.2 mjf 147 1.3.2.2 mjf ACCEPT_FILTER_LOCK(); 148 1.3.2.2 mjf SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 149 1.3.2.2 mjf if (strcmp(p->accf_name, name) == 0) 150 1.3.2.2 mjf break; 151 1.3.2.2 mjf ACCEPT_FILTER_UNLOCK(); 152 1.3.2.2 mjf 153 1.3.2.2 mjf return (p); 154 1.3.2.2 mjf } 155 1.3.2.2 mjf 156 1.3.2.2 mjf /* 157 1.3.2.2 mjf * Accept filter initialization routine. 158 1.3.2.2 mjf * This should be called only once. 159 1.3.2.2 mjf */ 160 1.3.2.2 mjf 161 1.3.2.2 mjf static int 162 1.3.2.2 mjf accept_filter_init0(void) 163 1.3.2.2 mjf { 164 1.3.2.2 mjf mutex_init(&accept_filter_mtx, MUTEX_DEFAULT, IPL_NET); 165 1.3.2.2 mjf 166 1.3.2.2 mjf return 0; 167 1.3.2.2 mjf } 168 1.3.2.2 mjf 169 1.3.2.2 mjf /* 170 1.3.2.2 mjf * Initialization routine: This can also be replaced with 171 1.3.2.2 mjf * accept_filt_generic_mod_event for attaching new accept filter. 172 1.3.2.2 mjf */ 173 1.3.2.2 mjf 174 1.3.2.2 mjf void 175 1.3.2.2 mjf accept_filter_init(void) 176 1.3.2.2 mjf { 177 1.3.2.2 mjf static ONCE_DECL(accept_filter_init_once); 178 1.3.2.2 mjf 179 1.3.2.2 mjf RUN_ONCE(&accept_filter_init_once, accept_filter_init0); 180 1.3.2.2 mjf } 181 1.3.2.2 mjf 182 1.3.2.2 mjf int 183 1.3.2.2 mjf accept_filt_generic_mod_event(struct lkm_table *lkmtp, int event, void *data) 184 1.3.2.2 mjf { 185 1.3.2.2 mjf struct accept_filter *p; 186 1.3.2.2 mjf struct accept_filter *accfp = (struct accept_filter *) data; 187 1.3.2.2 mjf int error; 188 1.3.2.2 mjf 189 1.3.2.2 mjf switch (event) { 190 1.3.2.2 mjf case LKM_E_LOAD: 191 1.3.2.2 mjf accept_filter_init(); 192 1.3.2.2 mjf MALLOC(p, struct accept_filter *, sizeof(*p), M_ACCF, 193 1.3.2.2 mjf M_WAITOK); 194 1.3.2.2 mjf bcopy(accfp, p, sizeof(*p)); 195 1.3.2.2 mjf error = accept_filt_add(p); 196 1.3.2.2 mjf break; 197 1.3.2.2 mjf 198 1.3.2.2 mjf case LKM_E_UNLOAD: 199 1.3.2.2 mjf /* 200 1.3.2.2 mjf * Do not support unloading yet. we don't keep track of 201 1.3.2.2 mjf * refcounts and unloading an accept filter callback and then 202 1.3.2.2 mjf * having it called is a bad thing. A simple fix would be to 203 1.3.2.2 mjf * track the refcount in the struct accept_filter. 204 1.3.2.2 mjf */ 205 1.3.2.2 mjf if (unloadable != 0) { 206 1.3.2.2 mjf error = accept_filt_del(accfp->accf_name); 207 1.3.2.2 mjf } else 208 1.3.2.2 mjf error = EOPNOTSUPP; 209 1.3.2.2 mjf break; 210 1.3.2.2 mjf 211 1.3.2.2 mjf case LKM_E_STAT: 212 1.3.2.2 mjf error = 0; 213 1.3.2.2 mjf break; 214 1.3.2.2 mjf 215 1.3.2.2 mjf default: 216 1.3.2.2 mjf error = EOPNOTSUPP; 217 1.3.2.2 mjf break; 218 1.3.2.2 mjf } 219 1.3.2.2 mjf 220 1.3.2.2 mjf return (error); 221 1.3.2.2 mjf } 222 1.3.2.2 mjf 223 1.3.2.2 mjf int 224 1.3.2.2 mjf do_getopt_accept_filter(struct socket *so, struct sockopt *sopt) 225 1.3.2.2 mjf { 226 1.3.2.2 mjf struct accept_filter_arg afa; 227 1.3.2.2 mjf int error; 228 1.3.2.2 mjf 229 1.3.2.2 mjf SOCK_LOCK(so); 230 1.3.2.2 mjf if ((so->so_options & SO_ACCEPTCONN) == 0) { 231 1.3.2.2 mjf error = EINVAL; 232 1.3.2.2 mjf goto out; 233 1.3.2.2 mjf } 234 1.3.2.2 mjf if ((so->so_options & SO_ACCEPTFILTER) == 0) { 235 1.3.2.2 mjf error = EINVAL; 236 1.3.2.2 mjf goto out; 237 1.3.2.2 mjf } 238 1.3.2.2 mjf 239 1.3.2.2 mjf memset(&afa, 0, sizeof(afa)); 240 1.3.2.2 mjf strcpy(afa.af_name, so->so_accf->so_accept_filter->accf_name); 241 1.3.2.2 mjf if (so->so_accf->so_accept_filter_str != NULL) 242 1.3.2.2 mjf strcpy(afa.af_arg, so->so_accf->so_accept_filter_str); 243 1.3.2.2 mjf error = sockopt_set(sopt, &afa, sizeof(afa)); 244 1.3.2.2 mjf out: 245 1.3.2.2 mjf SOCK_UNLOCK(so); 246 1.3.2.2 mjf return (error); 247 1.3.2.2 mjf } 248 1.3.2.2 mjf 249 1.3.2.2 mjf int 250 1.3.2.2 mjf do_setopt_accept_filter(struct socket *so, const struct sockopt *sopt) 251 1.3.2.2 mjf { 252 1.3.2.2 mjf struct accept_filter_arg afa; 253 1.3.2.2 mjf struct accept_filter *afp; 254 1.3.2.2 mjf struct so_accf *newaf; 255 1.3.2.2 mjf int error; 256 1.3.2.2 mjf 257 1.3.2.2 mjf /* 258 1.3.2.2 mjf * Handle the simple delete case first. 259 1.3.2.2 mjf */ 260 1.3.2.2 mjf if (sopt == NULL || sopt->sopt_size == 0) { 261 1.3.2.2 mjf SOCK_LOCK(so); 262 1.3.2.2 mjf if ((so->so_options & SO_ACCEPTCONN) == 0) { 263 1.3.2.2 mjf SOCK_UNLOCK(so); 264 1.3.2.2 mjf return (EINVAL); 265 1.3.2.2 mjf } 266 1.3.2.2 mjf if (so->so_accf != NULL) { 267 1.3.2.2 mjf struct so_accf *af = so->so_accf; 268 1.3.2.2 mjf if (af->so_accept_filter != NULL && 269 1.3.2.2 mjf af->so_accept_filter->accf_destroy != NULL) { 270 1.3.2.2 mjf af->so_accept_filter->accf_destroy(so); 271 1.3.2.2 mjf } 272 1.3.2.2 mjf if (af->so_accept_filter_str != NULL) 273 1.3.2.2 mjf FREE(af->so_accept_filter_str, M_ACCF); 274 1.3.2.2 mjf FREE(af, M_ACCF); 275 1.3.2.2 mjf so->so_accf = NULL; 276 1.3.2.2 mjf } 277 1.3.2.2 mjf so->so_options &= ~SO_ACCEPTFILTER; 278 1.3.2.2 mjf SOCK_UNLOCK(so); 279 1.3.2.2 mjf return (0); 280 1.3.2.2 mjf } 281 1.3.2.2 mjf 282 1.3.2.2 mjf /* 283 1.3.2.2 mjf * Pre-allocate any memory we may need later to avoid blocking at 284 1.3.2.2 mjf * untimely moments. This does not optimize for invalid arguments. 285 1.3.2.2 mjf */ 286 1.3.2.2 mjf error = sockopt_get(sopt, &afa, sizeof(afa)); 287 1.3.2.2 mjf if (error) { 288 1.3.2.2 mjf return (error); 289 1.3.2.2 mjf } 290 1.3.2.2 mjf afa.af_name[sizeof(afa.af_name)-1] = '\0'; 291 1.3.2.2 mjf afa.af_arg[sizeof(afa.af_arg)-1] = '\0'; 292 1.3.2.2 mjf afp = accept_filt_get(afa.af_name); 293 1.3.2.2 mjf if (afp == NULL) { 294 1.3.2.2 mjf return (ENOENT); 295 1.3.2.2 mjf } 296 1.3.2.2 mjf /* 297 1.3.2.2 mjf * Allocate the new accept filter instance storage. We may 298 1.3.2.2 mjf * have to free it again later if we fail to attach it. If 299 1.3.2.2 mjf * attached properly, 'newaf' is NULLed to avoid a free() 300 1.3.2.2 mjf * while in use. 301 1.3.2.2 mjf */ 302 1.3.2.2 mjf MALLOC(newaf, struct so_accf *, sizeof(*newaf), M_ACCF, M_WAITOK | 303 1.3.2.2 mjf M_ZERO); 304 1.3.2.2 mjf if (afp->accf_create != NULL && afa.af_name[0] != '\0') { 305 1.3.2.2 mjf int len = strlen(afa.af_name) + 1; 306 1.3.2.2 mjf MALLOC(newaf->so_accept_filter_str, char *, len, M_ACCF, 307 1.3.2.2 mjf M_WAITOK); 308 1.3.2.2 mjf strcpy(newaf->so_accept_filter_str, afa.af_name); 309 1.3.2.2 mjf } 310 1.3.2.2 mjf 311 1.3.2.2 mjf /* 312 1.3.2.2 mjf * Require a listen socket; don't try to replace an existing filter 313 1.3.2.2 mjf * without first removing it. 314 1.3.2.2 mjf */ 315 1.3.2.2 mjf SOCK_LOCK(so); 316 1.3.2.2 mjf if (((so->so_options & SO_ACCEPTCONN) == 0) || 317 1.3.2.2 mjf (so->so_accf != NULL)) { 318 1.3.2.2 mjf error = EINVAL; 319 1.3.2.2 mjf goto out; 320 1.3.2.2 mjf } 321 1.3.2.2 mjf 322 1.3.2.2 mjf /* 323 1.3.2.2 mjf * Invoke the accf_create() method of the filter if required. The 324 1.3.2.2 mjf * socket mutex is held over this call, so create methods for filters 325 1.3.2.2 mjf * can't block. 326 1.3.2.2 mjf */ 327 1.3.2.2 mjf if (afp->accf_create != NULL) { 328 1.3.2.2 mjf newaf->so_accept_filter_arg = 329 1.3.2.2 mjf afp->accf_create(so, afa.af_arg); 330 1.3.2.2 mjf if (newaf->so_accept_filter_arg == NULL) { 331 1.3.2.2 mjf error = EINVAL; 332 1.3.2.2 mjf goto out; 333 1.3.2.2 mjf } 334 1.3.2.2 mjf } 335 1.3.2.2 mjf newaf->so_accept_filter = afp; 336 1.3.2.2 mjf so->so_accf = newaf; 337 1.3.2.2 mjf so->so_options |= SO_ACCEPTFILTER; 338 1.3.2.2 mjf newaf = NULL; 339 1.3.2.2 mjf out: 340 1.3.2.2 mjf SOCK_UNLOCK(so); 341 1.3.2.2 mjf if (newaf != NULL) { 342 1.3.2.2 mjf if (newaf->so_accept_filter_str != NULL) 343 1.3.2.2 mjf FREE(newaf->so_accept_filter_str, M_ACCF); 344 1.3.2.2 mjf FREE(newaf, M_ACCF); 345 1.3.2.2 mjf } 346 1.3.2.2 mjf return (error); 347 1.3.2.2 mjf } 348
Indexes created Thu Oct 23 22:10:10 GMT 2025