1 /* $NetBSD: addr.c,v 1.2 2021/03/05 17:47:15 christos Exp $ */ 2 /* $OpenBSD: addr.c,v 1.1 2021/01/09 11:58:50 dtucker Exp $ */ 3 4 /* 5 * Copyright (c) 2004-2008 Damien Miller <djm@mindrot.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include "includes.h" 21 __RCSID("$NetBSD: addr.c,v 1.2 2021/03/05 17:47:15 christos Exp $"); 22 23 #include <sys/types.h> 24 #include <sys/socket.h> 25 #include <netinet/in.h> 26 #include <arpa/inet.h> 27 28 #include <netdb.h> 29 #include <string.h> 30 #include <stdlib.h> 31 #include <stdio.h> 32 33 #include "addr.h" 34 35 #define _SA(x) ((struct sockaddr *)(x)) 36 37 int 38 addr_unicast_masklen(int af) 39 { 40 switch (af) { 41 case AF_INET: 42 return 32; 43 case AF_INET6: 44 return 128; 45 default: 46 return -1; 47 } 48 } 49 50 static inline int 51 masklen_valid(int af, u_int masklen) 52 { 53 switch (af) { 54 case AF_INET: 55 return masklen <= 32 ? 0 : -1; 56 case AF_INET6: 57 return masklen <= 128 ? 0 : -1; 58 default: 59 return -1; 60 } 61 } 62 63 int 64 addr_xaddr_to_sa(const struct xaddr *xa, struct sockaddr *sa, socklen_t *len, 65 u_int16_t port) 66 { 67 struct sockaddr_in *in4 = (struct sockaddr_in *)sa; 68 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)sa; 69 70 if (xa == NULL || sa == NULL || len == NULL) 71 return -1; 72 73 switch (xa->af) { 74 case AF_INET: 75 if (*len < sizeof(*in4)) 76 return -1; 77 memset(sa, '\0', sizeof(*in4)); 78 *len = sizeof(*in4); 79 #ifdef SOCK_HAS_LEN 80 in4->sin_len = sizeof(*in4); 81 #endif 82 in4->sin_family = AF_INET; 83 in4->sin_port = htons(port); 84 memcpy(&in4->sin_addr, &xa->v4, sizeof(in4->sin_addr)); 85 break; 86 case AF_INET6: 87 if (*len < sizeof(*in6)) 88 return -1; 89 memset(sa, '\0', sizeof(*in6)); 90 *len = sizeof(*in6); 91 #ifdef SOCK_HAS_LEN 92 in6->sin6_len = sizeof(*in6); 93 #endif 94 in6->sin6_family = AF_INET6; 95 in6->sin6_port = htons(port); 96 memcpy(&in6->sin6_addr, &xa->v6, sizeof(in6->sin6_addr)); 97 in6->sin6_scope_id = xa->scope_id; 98 break; 99 default: 100 return -1; 101 } 102 return 0; 103 } 104 105 /* 106 * Convert struct sockaddr to struct xaddr 107 * Returns 0 on success, -1 on failure. 108 */ 109 int 110 addr_sa_to_xaddr(struct sockaddr *sa, socklen_t slen, struct xaddr *xa) 111 { 112 struct sockaddr_in *in4 = (struct sockaddr_in *)sa; 113 struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)sa; 114 115 memset(xa, '\0', sizeof(*xa)); 116 117 switch (sa->sa_family) { 118 case AF_INET: 119 if (slen < (socklen_t)sizeof(*in4)) 120 return -1; 121 xa->af = AF_INET; 122 memcpy(&xa->v4, &in4->sin_addr, sizeof(xa->v4)); 123 break; 124 case AF_INET6: 125 if (slen < (socklen_t)sizeof(*in6)) 126 return -1; 127 xa->af = AF_INET6; 128 memcpy(&xa->v6, &in6->sin6_addr, sizeof(xa->v6)); 129 #ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_SCOPE_ID 130 xa->scope_id = in6->sin6_scope_id; 131 #endif 132 break; 133 default: 134 return -1; 135 } 136 137 return 0; 138 } 139 140 int 141 addr_invert(struct xaddr *n) 142 { 143 int i; 144 145 if (n == NULL) 146 return -1; 147 148 switch (n->af) { 149 case AF_INET: 150 n->v4.s_addr = ~n->v4.s_addr; 151 return 0; 152 case AF_INET6: 153 for (i = 0; i < 4; i++) 154 n->addr32[i] = ~n->addr32[i]; 155 return 0; 156 default: 157 return -1; 158 } 159 } 160 161 /* 162 * Calculate a netmask of length 'l' for address family 'af' and 163 * store it in 'n'. 164 * Returns 0 on success, -1 on failure. 165 */ 166 int 167 addr_netmask(int af, u_int l, struct xaddr *n) 168 { 169 int i; 170 171 if (masklen_valid(af, l) != 0 || n == NULL) 172 return -1; 173 174 memset(n, '\0', sizeof(*n)); 175 switch (af) { 176 case AF_INET: 177 n->af = AF_INET; 178 if (l == 0) 179 return 0; 180 n->v4.s_addr = htonl((0xffffffff << (32 - l)) & 0xffffffff); 181 return 0; 182 case AF_INET6: 183 n->af = AF_INET6; 184 for (i = 0; i < 4 && l >= 32; i++, l -= 32) 185 n->addr32[i] = 0xffffffffU; 186 if (i < 4 && l != 0) 187 n->addr32[i] = htonl((0xffffffff << (32 - l)) & 188 0xffffffff); 189 return 0; 190 default: 191 return -1; 192 } 193 } 194 195 int 196 addr_hostmask(int af, u_int l, struct xaddr *n) 197 { 198 if (addr_netmask(af, l, n) == -1 || addr_invert(n) == -1) 199 return -1; 200 return 0; 201 } 202 203 /* 204 * Perform logical AND of addresses 'a' and 'b', storing result in 'dst'. 205 * Returns 0 on success, -1 on failure. 206 */ 207 int 208 addr_and(struct xaddr *dst, const struct xaddr *a, const struct xaddr *b) 209 { 210 int i; 211 212 if (dst == NULL || a == NULL || b == NULL || a->af != b->af) 213 return -1; 214 215 memcpy(dst, a, sizeof(*dst)); 216 switch (a->af) { 217 case AF_INET: 218 dst->v4.s_addr &= b->v4.s_addr; 219 return 0; 220 case AF_INET6: 221 dst->scope_id = a->scope_id; 222 for (i = 0; i < 4; i++) 223 dst->addr32[i] &= b->addr32[i]; 224 return 0; 225 default: 226 return -1; 227 } 228 } 229 230 int 231 addr_cmp(const struct xaddr *a, const struct xaddr *b) 232 { 233 int i; 234 235 if (a->af != b->af) 236 return (a->af == AF_INET6 ? 1 : -1); 237 238 switch (a->af) { 239 case AF_INET: 240 /* 241 * Can't just subtract here as 255.255.255.255 - 0.0.0.0 is 242 * too big to fit into a signed int 243 */ 244 if (a->v4.s_addr == b->v4.s_addr) 245 return 0; 246 return (ntohl(a->v4.s_addr) > ntohl(b->v4.s_addr) ? 1 : -1); 247 case AF_INET6:; 248 /* 249 * Do this a byte at a time to avoid the above issue and 250 * any endian problems 251 */ 252 for (i = 0; i < 16; i++) 253 if (a->addr8[i] - b->addr8[i] != 0) 254 return (a->addr8[i] - b->addr8[i]); 255 if (a->scope_id == b->scope_id) 256 return (0); 257 return (a->scope_id > b->scope_id ? 1 : -1); 258 default: 259 return (-1); 260 } 261 } 262 263 int 264 addr_is_all0s(const struct xaddr *a) 265 { 266 int i; 267 268 switch (a->af) { 269 case AF_INET: 270 return (a->v4.s_addr == 0 ? 0 : -1); 271 case AF_INET6:; 272 for (i = 0; i < 4; i++) 273 if (a->addr32[i] != 0) 274 return -1; 275 return 0; 276 default: 277 return -1; 278 } 279 } 280 281 /* 282 * Test whether host portion of address 'a', as determined by 'masklen' 283 * is all zeros. 284 * Returns 0 on if host portion of address is all-zeros, 285 * -1 if not all zeros or on failure. 286 */ 287 int 288 addr_host_is_all0s(const struct xaddr *a, u_int masklen) 289 { 290 struct xaddr tmp_addr, tmp_mask, tmp_result; 291 292 memcpy(&tmp_addr, a, sizeof(tmp_addr)); 293 if (addr_hostmask(a->af, masklen, &tmp_mask) == -1) 294 return -1; 295 if (addr_and(&tmp_result, &tmp_addr, &tmp_mask) == -1) 296 return -1; 297 return addr_is_all0s(&tmp_result); 298 } 299 300 /* 301 * Parse string address 'p' into 'n' 302 * Returns 0 on success, -1 on failure. 303 */ 304 int 305 addr_pton(const char *p, struct xaddr *n) 306 { 307 struct addrinfo hints, *ai; 308 309 memset(&hints, '\0', sizeof(hints)); 310 hints.ai_flags = AI_NUMERICHOST; 311 312 if (p == NULL || getaddrinfo(p, NULL, &hints, &ai) != 0) 313 return -1; 314 315 if (ai == NULL || ai->ai_addr == NULL) 316 return -1; 317 318 if (n != NULL && addr_sa_to_xaddr(ai->ai_addr, ai->ai_addrlen, 319 n) == -1) { 320 freeaddrinfo(ai); 321 return -1; 322 } 323 324 freeaddrinfo(ai); 325 return 0; 326 } 327 328 int 329 addr_sa_pton(const char *h, const char *s, struct sockaddr *sa, socklen_t slen) 330 { 331 struct addrinfo hints, *ai; 332 333 memset(&hints, '\0', sizeof(hints)); 334 hints.ai_flags = AI_NUMERICHOST; 335 336 if (h == NULL || getaddrinfo(h, s, &hints, &ai) != 0) 337 return -1; 338 339 if (ai == NULL || ai->ai_addr == NULL) 340 return -1; 341 342 if (sa != NULL) { 343 if (slen < ai->ai_addrlen) 344 return -1; 345 memcpy(sa, &ai->ai_addr, ai->ai_addrlen); 346 } 347 348 freeaddrinfo(ai); 349 return 0; 350 } 351 352 int 353 addr_ntop(const struct xaddr *n, char *p, size_t len) 354 { 355 struct sockaddr_storage ss; 356 socklen_t slen = sizeof(ss); 357 358 if (addr_xaddr_to_sa(n, _SA(&ss), &slen, 0) == -1) 359 return -1; 360 if (n == NULL || p == NULL || len == 0) 361 return -1; 362 if (getnameinfo(_SA(&ss), slen, p, len, NULL, 0, 363 NI_NUMERICHOST) == -1) 364 return -1; 365 366 return 0; 367 } 368 369 /* 370 * Parse a CIDR address (x.x.x.x/y or xxxx:yyyy::/z). 371 * Return -1 on parse error, -2 on inconsistency or 0 on success. 372 */ 373 int 374 addr_pton_cidr(const char *p, struct xaddr *n, u_int *l) 375 { 376 struct xaddr tmp; 377 long unsigned int masklen = 999; 378 char addrbuf[64], *mp, *cp; 379 380 /* Don't modify argument */ 381 if (p == NULL || strlcpy(addrbuf, p, sizeof(addrbuf)) >= sizeof(addrbuf)) 382 return -1; 383 384 if ((mp = strchr(addrbuf, '/')) != NULL) { 385 *mp = '\0'; 386 mp++; 387 masklen = strtoul(mp, &cp, 10); 388 if (*mp == '\0' || *cp != '\0' || masklen > 128) 389 return -1; 390 } 391 392 if (addr_pton(addrbuf, &tmp) == -1) 393 return -1; 394 395 if (mp == NULL) 396 masklen = addr_unicast_masklen(tmp.af); 397 if (masklen_valid(tmp.af, masklen) == -1) 398 return -2; 399 if (addr_host_is_all0s(&tmp, masklen) != 0) 400 return -2; 401 402 if (n != NULL) 403 memcpy(n, &tmp, sizeof(*n)); 404 if (l != NULL) 405 *l = masklen; 406 407 return 0; 408 } 409 410 int 411 addr_netmatch(const struct xaddr *host, const struct xaddr *net, u_int masklen) 412 { 413 struct xaddr tmp_mask, tmp_result; 414 415 if (host->af != net->af) 416 return -1; 417 418 if (addr_netmask(host->af, masklen, &tmp_mask) == -1) 419 return -1; 420 if (addr_and(&tmp_result, host, &tmp_mask) == -1) 421 return -1; 422 return addr_cmp(&tmp_result, net); 423 } 424