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_ddb.h" 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 36 #include <sys/param.h> 37 #include <sys/types.h> 38 #include <sys/kernel.h> 39 #include <sys/systm.h> 40 #include <sys/errno.h> 41 #include <sys/sysproto.h> 42 #include <sys/malloc.h> 43 #include <sys/osd.h> 44 #include <sys/priv.h> 45 #include <sys/proc.h> 46 #include <sys/taskqueue.h> 47 #include <sys/fcntl.h> 48 #include <sys/jail.h> 49 #include <sys/lock.h> 50 #include <sys/mutex.h> 51 #include <sys/racct.h> 52 #include <sys/refcount.h> 53 #include <sys/sx.h> 54 #include <sys/namei.h> 55 #include <sys/mount.h> 56 #include <sys/queue.h> 57 #include <sys/socket.h> 58 #include <sys/syscallsubr.h> 59 #include <sys/sysctl.h> 60 #include <sys/vnode.h> 61 62 #include <net/if.h> 63 #include <net/vnet.h> 64 65 #include <netinet/in.h> 66 67 static in_addr_t 68 prison_primary_ip4(const struct prison *pr) 69 { 70 71 return (((const struct in_addr *)prison_ip_get0(pr, PR_INET))->s_addr); 72 } 73 74 int 75 prison_qcmp_v4(const void *ip1, const void *ip2) 76 { 77 in_addr_t iaa, iab; 78 79 /* 80 * We need to compare in HBO here to get the list sorted as expected 81 * by the result of the code. Sorting NBO addresses gives you 82 * interesting results. If you do not understand, do not try. 83 */ 84 iaa = ntohl(((const struct in_addr *)ip1)->s_addr); 85 iab = ntohl(((const struct in_addr *)ip2)->s_addr); 86 87 /* 88 * Do not simply return the difference of the two numbers, the int is 89 * not wide enough. 90 */ 91 if (iaa > iab) 92 return (1); 93 else if (iaa < iab) 94 return (-1); 95 else 96 return (0); 97 } 98 99 bool 100 prison_valid_v4(const void *ip) 101 { 102 in_addr_t ia = ((const struct in_addr *)ip)->s_addr; 103 104 /* 105 * We do not have to care about byte order for these 106 * checks so we will do them in NBO. 107 */ 108 return (ia != INADDR_ANY && ia != INADDR_BROADCAST); 109 } 110 111 /* 112 * Pass back primary IPv4 address of this jail. 113 * 114 * If not restricted return success but do not alter the address. Caller has 115 * to make sure to initialize it correctly (e.g. INADDR_ANY). 116 * 117 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv4. 118 * Address returned in NBO. 119 */ 120 int 121 prison_get_ip4(struct ucred *cred, struct in_addr *ia) 122 { 123 struct prison *pr; 124 125 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 126 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 127 128 pr = cred->cr_prison; 129 if (!(pr->pr_flags & PR_IP4)) 130 return (0); 131 mtx_lock(&pr->pr_mtx); 132 if (!(pr->pr_flags & PR_IP4)) { 133 mtx_unlock(&pr->pr_mtx); 134 return (0); 135 } 136 if (pr->pr_addrs[PR_INET] == NULL) { 137 mtx_unlock(&pr->pr_mtx); 138 return (EAFNOSUPPORT); 139 } 140 141 ia->s_addr = prison_primary_ip4(pr); 142 mtx_unlock(&pr->pr_mtx); 143 return (0); 144 } 145 146 /* 147 * Return true if we should do proper source address selection or are not jailed. 148 * We will return false if we should bypass source address selection in favour 149 * of the primary jail IPv4 address. Only in this case *ia will be updated and 150 * returned in NBO. 151 * Return true, even in case this jail does not allow IPv4. 152 */ 153 bool 154 prison_saddrsel_ip4(struct ucred *cred, struct in_addr *ia) 155 { 156 struct prison *pr; 157 struct in_addr lia; 158 159 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 160 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 161 162 if (!jailed(cred)) 163 return (true); 164 165 pr = cred->cr_prison; 166 if (pr->pr_flags & PR_IP4_SADDRSEL) 167 return (true); 168 169 lia.s_addr = INADDR_ANY; 170 if (prison_get_ip4(cred, &lia) != 0) 171 return (true); 172 if (lia.s_addr == INADDR_ANY) 173 return (true); 174 175 ia->s_addr = lia.s_addr; 176 return (false); 177 } 178 179 /* 180 * Return true if pr1 and pr2 have the same IPv4 address restrictions. 181 */ 182 bool 183 prison_equal_ip4(struct prison *pr1, struct prison *pr2) 184 { 185 186 if (pr1 == pr2) 187 return (true); 188 189 /* 190 * No need to lock since the PR_IP4_USER flag can't be altered for 191 * existing prisons. 192 */ 193 while (pr1 != &prison0 && 194 #ifdef VIMAGE 195 !(pr1->pr_flags & PR_VNET) && 196 #endif 197 !(pr1->pr_flags & PR_IP4_USER)) 198 pr1 = pr1->pr_parent; 199 while (pr2 != &prison0 && 200 #ifdef VIMAGE 201 !(pr2->pr_flags & PR_VNET) && 202 #endif 203 !(pr2->pr_flags & PR_IP4_USER)) 204 pr2 = pr2->pr_parent; 205 return (pr1 == pr2); 206 } 207 208 /* 209 * Make sure our (source) address is set to something meaningful to this 210 * jail. 211 * 212 * Returns 0 if jail doesn't restrict IPv4 or if address belongs to jail, 213 * EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if the jail 214 * doesn't allow IPv4. Address passed in in NBO and returned in NBO. 215 */ 216 int 217 prison_local_ip4(struct ucred *cred, struct in_addr *ia) 218 { 219 struct prison *pr; 220 struct in_addr ia0; 221 int error; 222 223 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 224 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 225 226 pr = cred->cr_prison; 227 if (!(pr->pr_flags & PR_IP4)) 228 return (0); 229 mtx_lock(&pr->pr_mtx); 230 if (!(pr->pr_flags & PR_IP4)) { 231 mtx_unlock(&pr->pr_mtx); 232 return (0); 233 } 234 if (pr->pr_addrs[PR_INET] == NULL) { 235 mtx_unlock(&pr->pr_mtx); 236 return (EAFNOSUPPORT); 237 } 238 239 ia0.s_addr = ntohl(ia->s_addr); 240 241 if (ia0.s_addr == INADDR_ANY) { 242 /* 243 * In case there is only 1 IPv4 address, bind directly. 244 */ 245 if (prison_ip_cnt(pr, PR_INET) == 1) 246 ia->s_addr = prison_primary_ip4(pr); 247 mtx_unlock(&pr->pr_mtx); 248 return (0); 249 } 250 251 error = prison_check_ip4_locked(pr, ia); 252 if (error == EADDRNOTAVAIL && ia0.s_addr == INADDR_LOOPBACK) { 253 ia->s_addr = prison_primary_ip4(pr); 254 error = 0; 255 } 256 257 mtx_unlock(&pr->pr_mtx); 258 return (error); 259 } 260 261 /* 262 * Rewrite destination address in case we will connect to loopback address. 263 * 264 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv4. 265 * Address passed in in NBO and returned in NBO. 266 */ 267 int 268 prison_remote_ip4(struct ucred *cred, struct in_addr *ia) 269 { 270 struct prison *pr; 271 272 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 273 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 274 275 pr = cred->cr_prison; 276 if (!(pr->pr_flags & PR_IP4)) 277 return (0); 278 mtx_lock(&pr->pr_mtx); 279 if (!(pr->pr_flags & PR_IP4)) { 280 mtx_unlock(&pr->pr_mtx); 281 return (0); 282 } 283 if (pr->pr_addrs[PR_INET] == NULL) { 284 mtx_unlock(&pr->pr_mtx); 285 return (EAFNOSUPPORT); 286 } 287 288 if (ntohl(ia->s_addr) == INADDR_LOOPBACK && 289 prison_check_ip4_locked(pr, ia) == EADDRNOTAVAIL) { 290 ia->s_addr = prison_primary_ip4(pr); 291 mtx_unlock(&pr->pr_mtx); 292 return (0); 293 } 294 295 /* 296 * Return success because nothing had to be changed. 297 */ 298 mtx_unlock(&pr->pr_mtx); 299 return (0); 300 } 301 302 /* 303 * Check if given address belongs to the jail referenced by cred/prison. 304 * 305 * Returns 0 if address belongs to jail, 306 * EADDRNOTAVAIL if the address doesn't belong to the jail. 307 */ 308 int 309 prison_check_ip4_locked(const struct prison *pr, const struct in_addr *ia) 310 { 311 312 if (!(pr->pr_flags & PR_IP4)) 313 return (0); 314 315 return (prison_ip_check(pr, PR_INET, ia)); 316 } 317 318 int 319 prison_check_ip4(const struct ucred *cred, const struct in_addr *ia) 320 { 321 struct prison *pr; 322 int error; 323 324 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 325 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 326 327 pr = cred->cr_prison; 328 if (!(pr->pr_flags & PR_IP4)) 329 return (0); 330 mtx_lock(&pr->pr_mtx); 331 if (!(pr->pr_flags & PR_IP4)) { 332 mtx_unlock(&pr->pr_mtx); 333 return (0); 334 } 335 if (pr->pr_addrs[PR_INET] == NULL) { 336 mtx_unlock(&pr->pr_mtx); 337 return (EAFNOSUPPORT); 338 } 339 340 error = prison_check_ip4_locked(pr, ia); 341 mtx_unlock(&pr->pr_mtx); 342 return (error); 343 } 344