1 /*- 2 * Copyright (c) 1999 Poul-Henning Kamp. 3 * Copyright (c) 2008 Bjoern A. Zeeb. 4 * Copyright (c) 2009 James Gritton. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_compat.h" 33 #include "opt_ddb.h" 34 #include "opt_inet.h" 35 #include "opt_inet6.h" 36 37 #include <sys/param.h> 38 #include <sys/types.h> 39 #include <sys/kernel.h> 40 #include <sys/systm.h> 41 #include <sys/errno.h> 42 #include <sys/sysproto.h> 43 #include <sys/malloc.h> 44 #include <sys/osd.h> 45 #include <sys/priv.h> 46 #include <sys/proc.h> 47 #include <sys/taskqueue.h> 48 #include <sys/fcntl.h> 49 #include <sys/jail.h> 50 #include <sys/lock.h> 51 #include <sys/mutex.h> 52 #include <sys/racct.h> 53 #include <sys/refcount.h> 54 #include <sys/sx.h> 55 #include <sys/sysent.h> 56 #include <sys/namei.h> 57 #include <sys/mount.h> 58 #include <sys/queue.h> 59 #include <sys/socket.h> 60 #include <sys/syscallsubr.h> 61 #include <sys/sysctl.h> 62 #include <sys/vnode.h> 63 64 #include <net/if.h> 65 #include <net/vnet.h> 66 67 #include <netinet/in.h> 68 69 int 70 prison_qcmp_v6(const void *ip1, const void *ip2) 71 { 72 const struct in6_addr *ia6a, *ia6b; 73 int i, rc; 74 75 ia6a = (const struct in6_addr *)ip1; 76 ia6b = (const struct in6_addr *)ip2; 77 78 rc = 0; 79 for (i = 0; rc == 0 && i < sizeof(struct in6_addr); i++) { 80 if (ia6a->s6_addr[i] > ia6b->s6_addr[i]) 81 rc = 1; 82 else if (ia6a->s6_addr[i] < ia6b->s6_addr[i]) 83 rc = -1; 84 } 85 return (rc); 86 } 87 88 int 89 prison_restrict_ip6(struct prison *pr, struct in6_addr *newip6) 90 { 91 int ii, ij, used; 92 struct prison *ppr; 93 94 ppr = pr->pr_parent; 95 if (!(pr->pr_flags & PR_IP6_USER)) { 96 /* This has no user settings, so just copy the parent's list. */ 97 if (pr->pr_ip6s < ppr->pr_ip6s) { 98 /* 99 * There's no room for the parent's list. Use the 100 * new list buffer, which is assumed to be big enough 101 * (if it was passed). If there's no buffer, try to 102 * allocate one. 103 */ 104 used = 1; 105 if (newip6 == NULL) { 106 newip6 = malloc(ppr->pr_ip6s * sizeof(*newip6), 107 M_PRISON, M_NOWAIT); 108 if (newip6 != NULL) 109 used = 0; 110 } 111 if (newip6 != NULL) { 112 bcopy(ppr->pr_ip6, newip6, 113 ppr->pr_ip6s * sizeof(*newip6)); 114 free(pr->pr_ip6, M_PRISON); 115 pr->pr_ip6 = newip6; 116 pr->pr_ip6s = ppr->pr_ip6s; 117 } 118 return (used); 119 } 120 pr->pr_ip6s = ppr->pr_ip6s; 121 if (pr->pr_ip6s > 0) 122 bcopy(ppr->pr_ip6, pr->pr_ip6, 123 pr->pr_ip6s * sizeof(*newip6)); 124 else if (pr->pr_ip6 != NULL) { 125 free(pr->pr_ip6, M_PRISON); 126 pr->pr_ip6 = NULL; 127 } 128 } else if (pr->pr_ip6s > 0) { 129 /* Remove addresses that aren't in the parent. */ 130 for (ij = 0; ij < ppr->pr_ip6s; ij++) 131 if (IN6_ARE_ADDR_EQUAL(&pr->pr_ip6[0], 132 &ppr->pr_ip6[ij])) 133 break; 134 if (ij < ppr->pr_ip6s) 135 ii = 1; 136 else { 137 bcopy(pr->pr_ip6 + 1, pr->pr_ip6, 138 --pr->pr_ip6s * sizeof(*pr->pr_ip6)); 139 ii = 0; 140 } 141 for (ij = 1; ii < pr->pr_ip6s; ) { 142 if (IN6_ARE_ADDR_EQUAL(&pr->pr_ip6[ii], 143 &ppr->pr_ip6[0])) { 144 ii++; 145 continue; 146 } 147 switch (ij >= ppr->pr_ip6s ? -1 : 148 prison_qcmp_v6(&pr->pr_ip6[ii], &ppr->pr_ip6[ij])) { 149 case -1: 150 bcopy(pr->pr_ip6 + ii + 1, pr->pr_ip6 + ii, 151 (--pr->pr_ip6s - ii) * sizeof(*pr->pr_ip6)); 152 break; 153 case 0: 154 ii++; 155 ij++; 156 break; 157 case 1: 158 ij++; 159 break; 160 } 161 } 162 if (pr->pr_ip6s == 0) { 163 free(pr->pr_ip6, M_PRISON); 164 pr->pr_ip6 = NULL; 165 } 166 } 167 return 0; 168 } 169 170 /* 171 * Pass back primary IPv6 address for this jail. 172 * 173 * If not restricted return success but do not alter the address. Caller has 174 * to make sure to initialize it correctly (e.g. IN6ADDR_ANY_INIT). 175 * 176 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv6. 177 */ 178 int 179 prison_get_ip6(struct ucred *cred, struct in6_addr *ia6) 180 { 181 struct prison *pr; 182 183 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 184 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__)); 185 186 pr = cred->cr_prison; 187 if (!(pr->pr_flags & PR_IP6)) 188 return (0); 189 mtx_lock(&pr->pr_mtx); 190 if (!(pr->pr_flags & PR_IP6)) { 191 mtx_unlock(&pr->pr_mtx); 192 return (0); 193 } 194 if (pr->pr_ip6 == NULL) { 195 mtx_unlock(&pr->pr_mtx); 196 return (EAFNOSUPPORT); 197 } 198 199 bcopy(&pr->pr_ip6[0], ia6, sizeof(struct in6_addr)); 200 mtx_unlock(&pr->pr_mtx); 201 return (0); 202 } 203 204 /* 205 * Return 1 if we should do proper source address selection or are not jailed. 206 * We will return 0 if we should bypass source address selection in favour 207 * of the primary jail IPv6 address. Only in this case *ia will be updated and 208 * returned in NBO. 209 * Return EAFNOSUPPORT, in case this jail does not allow IPv6. 210 */ 211 int 212 prison_saddrsel_ip6(struct ucred *cred, struct in6_addr *ia6) 213 { 214 struct prison *pr; 215 struct in6_addr lia6; 216 int error; 217 218 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 219 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__)); 220 221 if (!jailed(cred)) 222 return (1); 223 224 pr = cred->cr_prison; 225 if (pr->pr_flags & PR_IP6_SADDRSEL) 226 return (1); 227 228 lia6 = in6addr_any; 229 error = prison_get_ip6(cred, &lia6); 230 if (error) 231 return (error); 232 if (IN6_IS_ADDR_UNSPECIFIED(&lia6)) 233 return (1); 234 235 bcopy(&lia6, ia6, sizeof(struct in6_addr)); 236 return (0); 237 } 238 239 /* 240 * Return true if pr1 and pr2 have the same IPv6 address restrictions. 241 */ 242 int 243 prison_equal_ip6(struct prison *pr1, struct prison *pr2) 244 { 245 246 if (pr1 == pr2) 247 return (1); 248 249 while (pr1 != &prison0 && 250 #ifdef VIMAGE 251 !(pr1->pr_flags & PR_VNET) && 252 #endif 253 !(pr1->pr_flags & PR_IP6_USER)) 254 pr1 = pr1->pr_parent; 255 while (pr2 != &prison0 && 256 #ifdef VIMAGE 257 !(pr2->pr_flags & PR_VNET) && 258 #endif 259 !(pr2->pr_flags & PR_IP6_USER)) 260 pr2 = pr2->pr_parent; 261 return (pr1 == pr2); 262 } 263 264 /* 265 * Make sure our (source) address is set to something meaningful to this jail. 266 * 267 * v6only should be set based on (inp->inp_flags & IN6P_IPV6_V6ONLY != 0) 268 * when needed while binding. 269 * 270 * Returns 0 if jail doesn't restrict IPv6 or if address belongs to jail, 271 * EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if the jail 272 * doesn't allow IPv6. 273 */ 274 int 275 prison_local_ip6(struct ucred *cred, struct in6_addr *ia6, int v6only) 276 { 277 struct prison *pr; 278 int error; 279 280 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 281 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__)); 282 283 pr = cred->cr_prison; 284 if (!(pr->pr_flags & PR_IP6)) 285 return (0); 286 mtx_lock(&pr->pr_mtx); 287 if (!(pr->pr_flags & PR_IP6)) { 288 mtx_unlock(&pr->pr_mtx); 289 return (0); 290 } 291 if (pr->pr_ip6 == NULL) { 292 mtx_unlock(&pr->pr_mtx); 293 return (EAFNOSUPPORT); 294 } 295 296 if (IN6_IS_ADDR_UNSPECIFIED(ia6)) { 297 /* 298 * In case there is only 1 IPv6 address, and v6only is true, 299 * then bind directly. 300 */ 301 if (v6only != 0 && pr->pr_ip6s == 1) 302 bcopy(&pr->pr_ip6[0], ia6, sizeof(struct in6_addr)); 303 mtx_unlock(&pr->pr_mtx); 304 return (0); 305 } 306 307 error = prison_check_ip6_locked(pr, ia6); 308 if (error == EADDRNOTAVAIL && IN6_IS_ADDR_LOOPBACK(ia6)) { 309 bcopy(&pr->pr_ip6[0], ia6, sizeof(struct in6_addr)); 310 error = 0; 311 } 312 313 mtx_unlock(&pr->pr_mtx); 314 return (error); 315 } 316 317 /* 318 * Rewrite destination address in case we will connect to loopback address. 319 * 320 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv6. 321 */ 322 int 323 prison_remote_ip6(struct ucred *cred, struct in6_addr *ia6) 324 { 325 struct prison *pr; 326 327 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 328 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__)); 329 330 pr = cred->cr_prison; 331 if (!(pr->pr_flags & PR_IP6)) 332 return (0); 333 mtx_lock(&pr->pr_mtx); 334 if (!(pr->pr_flags & PR_IP6)) { 335 mtx_unlock(&pr->pr_mtx); 336 return (0); 337 } 338 if (pr->pr_ip6 == NULL) { 339 mtx_unlock(&pr->pr_mtx); 340 return (EAFNOSUPPORT); 341 } 342 343 if (IN6_IS_ADDR_LOOPBACK(ia6) && 344 prison_check_ip6_locked(pr, ia6) == EADDRNOTAVAIL) { 345 bcopy(&pr->pr_ip6[0], ia6, sizeof(struct in6_addr)); 346 mtx_unlock(&pr->pr_mtx); 347 return (0); 348 } 349 350 /* 351 * Return success because nothing had to be changed. 352 */ 353 mtx_unlock(&pr->pr_mtx); 354 return (0); 355 } 356 357 /* 358 * Check if given address belongs to the jail referenced by cred/prison. 359 * 360 * Returns 0 if address belongs to jail, 361 * EADDRNOTAVAIL if the address doesn't belong to the jail. 362 */ 363 int 364 prison_check_ip6_locked(const struct prison *pr, const struct in6_addr *ia6) 365 { 366 int i, a, z, d; 367 368 /* 369 * Check the primary IP. 370 */ 371 if (IN6_ARE_ADDR_EQUAL(&pr->pr_ip6[0], ia6)) 372 return (0); 373 374 /* 375 * All the other IPs are sorted so we can do a binary search. 376 */ 377 a = 0; 378 z = pr->pr_ip6s - 2; 379 while (a <= z) { 380 i = (a + z) / 2; 381 d = prison_qcmp_v6(&pr->pr_ip6[i+1], ia6); 382 if (d > 0) 383 z = i - 1; 384 else if (d < 0) 385 a = i + 1; 386 else 387 return (0); 388 } 389 390 return (EADDRNOTAVAIL); 391 } 392 393 int 394 prison_check_ip6(const struct ucred *cred, const struct in6_addr *ia6) 395 { 396 struct prison *pr; 397 int error; 398 399 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 400 KASSERT(ia6 != NULL, ("%s: ia6 is NULL", __func__)); 401 402 pr = cred->cr_prison; 403 if (!(pr->pr_flags & PR_IP6)) 404 return (0); 405 mtx_lock(&pr->pr_mtx); 406 if (!(pr->pr_flags & PR_IP6)) { 407 mtx_unlock(&pr->pr_mtx); 408 return (0); 409 } 410 if (pr->pr_ip6 == NULL) { 411 mtx_unlock(&pr->pr_mtx); 412 return (EAFNOSUPPORT); 413 } 414 415 error = prison_check_ip6_locked(pr, ia6); 416 mtx_unlock(&pr->pr_mtx); 417 return (error); 418 } 419