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 #include "opt_ddb.h" 31 #include "opt_inet.h" 32 #include "opt_inet6.h" 33 34 #include <sys/param.h> 35 #include <sys/types.h> 36 #include <sys/kernel.h> 37 #include <sys/systm.h> 38 #include <sys/errno.h> 39 #include <sys/sysproto.h> 40 #include <sys/malloc.h> 41 #include <sys/osd.h> 42 #include <sys/priv.h> 43 #include <sys/proc.h> 44 #include <sys/taskqueue.h> 45 #include <sys/fcntl.h> 46 #include <sys/jail.h> 47 #include <sys/lock.h> 48 #include <sys/mutex.h> 49 #include <sys/racct.h> 50 #include <sys/refcount.h> 51 #include <sys/sx.h> 52 #include <sys/namei.h> 53 #include <sys/mount.h> 54 #include <sys/queue.h> 55 #include <sys/socket.h> 56 #include <sys/syscallsubr.h> 57 #include <sys/sysctl.h> 58 #include <sys/vnode.h> 59 60 #include <net/if.h> 61 #include <net/vnet.h> 62 63 #include <netinet/in.h> 64 65 static in_addr_t 66 prison_primary_ip4(const struct prison *pr) 67 { 68 69 return (((const struct in_addr *)prison_ip_get0(pr, PR_INET))->s_addr); 70 } 71 72 int 73 prison_qcmp_v4(const void *ip1, const void *ip2) 74 { 75 in_addr_t iaa, iab; 76 77 /* 78 * We need to compare in HBO here to get the list sorted as expected 79 * by the result of the code. Sorting NBO addresses gives you 80 * interesting results. If you do not understand, do not try. 81 */ 82 iaa = ntohl(((const struct in_addr *)ip1)->s_addr); 83 iab = ntohl(((const struct in_addr *)ip2)->s_addr); 84 85 /* 86 * Do not simply return the difference of the two numbers, the int is 87 * not wide enough. 88 */ 89 if (iaa > iab) 90 return (1); 91 else if (iaa < iab) 92 return (-1); 93 else 94 return (0); 95 } 96 97 bool 98 prison_valid_v4(const void *ip) 99 { 100 return (!in_broadcast(*(const struct in_addr *)ip)); 101 } 102 103 /* 104 * Pass back primary IPv4 address of this jail. 105 * 106 * If not restricted return success but do not alter the address. Caller has 107 * to make sure to initialize it correctly (e.g. INADDR_ANY). 108 * 109 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv4. 110 * Address returned in NBO. 111 */ 112 int 113 prison_get_ip4(struct ucred *cred, struct in_addr *ia) 114 { 115 struct prison *pr; 116 117 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 118 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 119 120 pr = cred->cr_prison; 121 if (!(pr->pr_flags & PR_IP4)) 122 return (0); 123 mtx_lock(&pr->pr_mtx); 124 if (!(pr->pr_flags & PR_IP4)) { 125 mtx_unlock(&pr->pr_mtx); 126 return (0); 127 } 128 if (pr->pr_addrs[PR_INET] == NULL) { 129 mtx_unlock(&pr->pr_mtx); 130 return (EAFNOSUPPORT); 131 } 132 133 ia->s_addr = prison_primary_ip4(pr); 134 mtx_unlock(&pr->pr_mtx); 135 return (0); 136 } 137 138 /* 139 * Return true if we should do proper source address selection or are not jailed. 140 * We will return false if we should bypass source address selection in favour 141 * of the primary jail IPv4 address. Only in this case *ia will be updated and 142 * returned in NBO. 143 * Return true, even in case this jail does not allow IPv4. 144 */ 145 bool 146 prison_saddrsel_ip4(struct ucred *cred, struct in_addr *ia) 147 { 148 struct prison *pr; 149 struct in_addr lia; 150 151 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 152 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 153 154 if (!jailed(cred)) 155 return (true); 156 157 pr = cred->cr_prison; 158 if (pr->pr_flags & PR_IP4_SADDRSEL) 159 return (true); 160 161 lia.s_addr = INADDR_ANY; 162 if (prison_get_ip4(cred, &lia) != 0) 163 return (true); 164 if (lia.s_addr == INADDR_ANY) 165 return (true); 166 167 ia->s_addr = lia.s_addr; 168 return (false); 169 } 170 171 /* 172 * Return true if pr1 and pr2 have the same IPv4 address restrictions. 173 */ 174 bool 175 prison_equal_ip4(struct prison *pr1, struct prison *pr2) 176 { 177 178 if (pr1 == pr2) 179 return (true); 180 181 /* 182 * No need to lock since the PR_IP4_USER flag can't be altered for 183 * existing prisons. 184 */ 185 while (pr1 != &prison0 && 186 #ifdef VIMAGE 187 !(pr1->pr_flags & PR_VNET) && 188 #endif 189 !(pr1->pr_flags & PR_IP4_USER)) 190 pr1 = pr1->pr_parent; 191 while (pr2 != &prison0 && 192 #ifdef VIMAGE 193 !(pr2->pr_flags & PR_VNET) && 194 #endif 195 !(pr2->pr_flags & PR_IP4_USER)) 196 pr2 = pr2->pr_parent; 197 return (pr1 == pr2); 198 } 199 200 /* 201 * Make sure our (source) address is set to something meaningful to this 202 * jail. 203 * 204 * Returns 0 if jail doesn't restrict IPv4 or if address belongs to jail, 205 * EADDRNOTAVAIL if the address doesn't belong, or EAFNOSUPPORT if the jail 206 * doesn't allow IPv4. Address passed in in NBO and returned in NBO. 207 */ 208 int 209 prison_local_ip4(struct ucred *cred, struct in_addr *ia) 210 { 211 struct prison *pr; 212 struct in_addr ia0; 213 int error; 214 215 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 216 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 217 218 pr = cred->cr_prison; 219 if (!(pr->pr_flags & PR_IP4)) 220 return (0); 221 mtx_lock(&pr->pr_mtx); 222 if (!(pr->pr_flags & PR_IP4)) { 223 mtx_unlock(&pr->pr_mtx); 224 return (0); 225 } 226 if (pr->pr_addrs[PR_INET] == NULL) { 227 mtx_unlock(&pr->pr_mtx); 228 return (EAFNOSUPPORT); 229 } 230 231 ia0.s_addr = ntohl(ia->s_addr); 232 233 if (ia0.s_addr == INADDR_ANY) { 234 /* 235 * In case there is only 1 IPv4 address, bind directly. 236 */ 237 if (prison_ip_cnt(pr, PR_INET) == 1) 238 ia->s_addr = prison_primary_ip4(pr); 239 mtx_unlock(&pr->pr_mtx); 240 return (0); 241 } 242 243 error = prison_check_ip4_locked(pr, ia); 244 if (error == EADDRNOTAVAIL && ia0.s_addr == INADDR_LOOPBACK) { 245 ia->s_addr = prison_primary_ip4(pr); 246 error = 0; 247 } 248 249 mtx_unlock(&pr->pr_mtx); 250 return (error); 251 } 252 253 /* 254 * Rewrite destination address in case we will connect to loopback address. 255 * 256 * Returns 0 on success, EAFNOSUPPORT if the jail doesn't allow IPv4. 257 * Address passed in in NBO and returned in NBO. 258 */ 259 int 260 prison_remote_ip4(struct ucred *cred, struct in_addr *ia) 261 { 262 struct prison *pr; 263 264 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 265 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 266 267 pr = cred->cr_prison; 268 if (!(pr->pr_flags & PR_IP4)) 269 return (0); 270 mtx_lock(&pr->pr_mtx); 271 if (!(pr->pr_flags & PR_IP4)) { 272 mtx_unlock(&pr->pr_mtx); 273 return (0); 274 } 275 if (pr->pr_addrs[PR_INET] == NULL) { 276 mtx_unlock(&pr->pr_mtx); 277 return (EAFNOSUPPORT); 278 } 279 280 if (ntohl(ia->s_addr) == INADDR_LOOPBACK && 281 prison_check_ip4_locked(pr, ia) == EADDRNOTAVAIL) { 282 ia->s_addr = prison_primary_ip4(pr); 283 mtx_unlock(&pr->pr_mtx); 284 return (0); 285 } 286 287 /* 288 * Return success because nothing had to be changed. 289 */ 290 mtx_unlock(&pr->pr_mtx); 291 return (0); 292 } 293 294 /* 295 * Check if given address belongs to the jail referenced by cred/prison. 296 * 297 * Returns 0 if address belongs to jail, 298 * EADDRNOTAVAIL if the address doesn't belong to the jail. 299 */ 300 int 301 prison_check_ip4_locked(const struct prison *pr, const struct in_addr *ia) 302 { 303 304 if (!(pr->pr_flags & PR_IP4)) 305 return (0); 306 307 return (prison_ip_check(pr, PR_INET, ia)); 308 } 309 310 int 311 prison_check_ip4(const struct ucred *cred, const struct in_addr *ia) 312 { 313 struct prison *pr; 314 int error; 315 316 KASSERT(cred != NULL, ("%s: cred is NULL", __func__)); 317 KASSERT(ia != NULL, ("%s: ia is NULL", __func__)); 318 319 pr = cred->cr_prison; 320 if (!(pr->pr_flags & PR_IP4)) 321 return (0); 322 mtx_lock(&pr->pr_mtx); 323 if (!(pr->pr_flags & PR_IP4)) { 324 mtx_unlock(&pr->pr_mtx); 325 return (0); 326 } 327 if (pr->pr_addrs[PR_INET] == NULL) { 328 mtx_unlock(&pr->pr_mtx); 329 return (EAFNOSUPPORT); 330 } 331 332 error = prison_check_ip4_locked(pr, ia); 333 mtx_unlock(&pr->pr_mtx); 334 return (error); 335 } 336