1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 #include "opt_inet.h" 31 #include "opt_inet6.h" 32 #include <sys/types.h> 33 #include <sys/malloc.h> 34 #include <sys/rmlock.h> 35 #include <sys/socket.h> 36 37 #include <machine/stdarg.h> 38 39 #include <net/if.h> 40 #include <net/route.h> 41 #include <net/route/nhop.h> 42 43 #include <net/route/route_ctl.h> 44 #include <netlink/netlink.h> 45 #include <netlink/netlink_ctl.h> 46 #include <netlink/netlink_var.h> 47 #include <netlink/netlink_route.h> 48 49 #define DEBUG_MOD_NAME nl_parser 50 #define DEBUG_MAX_LEVEL LOG_DEBUG3 51 #include <netlink/netlink_debug.h> 52 _DECLARE_DEBUG(LOG_DEBUG); 53 54 bool 55 nlmsg_report_err_msg(struct nl_pstate *npt, const char *fmt, ...) 56 { 57 va_list ap; 58 59 if (npt->err_msg != NULL) 60 return (false); 61 char *buf = npt_alloc(npt, NL_MAX_ERROR_BUF); 62 if (buf == NULL) 63 return (false); 64 va_start(ap, fmt); 65 vsnprintf(buf, NL_MAX_ERROR_BUF, fmt, ap); 66 va_end(ap); 67 68 npt->err_msg = buf; 69 return (true); 70 } 71 72 bool 73 nlmsg_report_err_offset(struct nl_pstate *npt, uint32_t off) 74 { 75 if (npt->err_off != 0) 76 return (false); 77 npt->err_off = off; 78 return (true); 79 } 80 81 static const struct nlattr_parser * 82 search_states(const struct nlattr_parser *ps, int pslen, int key) 83 { 84 int left_i = 0, right_i = pslen - 1; 85 86 if (key < ps[0].type || key > ps[pslen - 1].type) 87 return (NULL); 88 89 while (left_i + 1 < right_i) { 90 int mid_i = (left_i + right_i) / 2; 91 if (key < ps[mid_i].type) 92 right_i = mid_i; 93 else if (key > ps[mid_i].type) 94 left_i = mid_i + 1; 95 else 96 return (&ps[mid_i]); 97 } 98 if (ps[left_i].type == key) 99 return (&ps[left_i]); 100 else if (ps[right_i].type == key) 101 return (&ps[right_i]); 102 return (NULL); 103 } 104 105 int 106 nl_parse_attrs_raw(struct nlattr *nla_head, int len, const struct nlattr_parser *ps, int pslen, 107 struct nl_pstate *npt, void *target) 108 { 109 struct nlattr *nla = NULL; 110 int error = 0; 111 112 NL_LOG(LOG_DEBUG3, "parse %p remaining_len %d", nla_head, len); 113 int orig_len = len; 114 NLA_FOREACH(nla, nla_head, len) { 115 NL_LOG(LOG_DEBUG3, ">> parsing %p attr_type %d len %d (rem %d)", nla, nla->nla_type, nla->nla_len, len); 116 if (nla->nla_len < sizeof(struct nlattr)) { 117 NLMSG_REPORT_ERR_MSG(npt, "Invalid attr %p type %d len: %d", 118 nla, nla->nla_type, nla->nla_len); 119 uint32_t off = (char *)nla - (char *)npt->hdr; 120 nlmsg_report_err_offset(npt, off); 121 return (EINVAL); 122 } 123 124 int nla_type = nla->nla_type & NLA_TYPE_MASK; 125 const struct nlattr_parser *s = search_states(ps, pslen, nla_type); 126 if (s != NULL) { 127 void *ptr = (void *)((char *)target + s->off); 128 error = s->cb(nla, npt, s->arg, ptr); 129 if (error != 0) { 130 uint32_t off = (char *)nla - (char *)npt->hdr; 131 nlmsg_report_err_offset(npt, off); 132 NL_LOG(LOG_DEBUG3, "parse failed att offset %u", off); 133 return (error); 134 } 135 } else { 136 /* Ignore non-specified attributes */ 137 NL_LOG(LOG_DEBUG3, "ignoring attr %d", nla->nla_type); 138 } 139 } 140 if (len >= sizeof(struct nlattr)) { 141 nla = (struct nlattr *)((char *)nla_head + (orig_len - len)); 142 NL_LOG(LOG_DEBUG3, " >>> end %p attr_type %d len %d", nla, 143 nla->nla_type, nla->nla_len); 144 } 145 NL_LOG(LOG_DEBUG3, "end parse: %p remaining_len %d", nla, len); 146 147 return (0); 148 } 149 150 int 151 nl_parse_attrs(struct nlmsghdr *hdr, int hdrlen, struct nlattr_parser *ps, int pslen, 152 struct nl_pstate *npt, void *target) 153 { 154 int off = NLMSG_HDRLEN + NETLINK_ALIGN(hdrlen); 155 int len = hdr->nlmsg_len - off; 156 struct nlattr *nla_head = (struct nlattr *)((char *)hdr + off); 157 158 return (nl_parse_attrs_raw(nla_head, len, ps, pslen, npt, target)); 159 } 160 161 int 162 nlattr_get_flag(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 163 { 164 if (__predict_false(NLA_DATA_LEN(nla) != 0)) { 165 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not a flag", 166 nla->nla_type, NLA_DATA_LEN(nla)); 167 return (EINVAL); 168 } 169 170 *((uint8_t *)target) = 1; 171 return (0); 172 } 173 174 static struct sockaddr * 175 parse_rta_ip4(void *rta_data, struct nl_pstate *npt, int *perror) 176 { 177 struct sockaddr_in *sin; 178 179 sin = (struct sockaddr_in *)npt_alloc_sockaddr(npt, sizeof(struct sockaddr_in)); 180 if (__predict_false(sin == NULL)) { 181 *perror = ENOBUFS; 182 return (NULL); 183 } 184 sin->sin_len = sizeof(struct sockaddr_in); 185 sin->sin_family = AF_INET; 186 memcpy(&sin->sin_addr, rta_data, sizeof(struct in_addr)); 187 return ((struct sockaddr *)sin); 188 } 189 190 static struct sockaddr * 191 parse_rta_ip6(void *rta_data, struct nl_pstate *npt, int *perror) 192 { 193 struct sockaddr_in6 *sin6; 194 195 sin6 = (struct sockaddr_in6 *)npt_alloc_sockaddr(npt, sizeof(struct sockaddr_in6)); 196 if (__predict_false(sin6 == NULL)) { 197 *perror = ENOBUFS; 198 return (NULL); 199 } 200 sin6->sin6_len = sizeof(struct sockaddr_in6); 201 sin6->sin6_family = AF_INET6; 202 memcpy(&sin6->sin6_addr, rta_data, sizeof(struct in6_addr)); 203 return ((struct sockaddr *)sin6); 204 } 205 206 static struct sockaddr * 207 parse_rta_ip(struct rtattr *rta, struct nl_pstate *npt, int *perror) 208 { 209 void *rta_data = NL_RTA_DATA(rta); 210 int rta_len = NL_RTA_DATA_LEN(rta); 211 212 if (rta_len == sizeof(struct in_addr)) { 213 return (parse_rta_ip4(rta_data, npt, perror)); 214 } else if (rta_len == sizeof(struct in6_addr)) { 215 return (parse_rta_ip6(rta_data, npt, perror)); 216 } else { 217 NLMSG_REPORT_ERR_MSG(npt, "unknown IP len: %d for rta type %d", 218 rta_len, rta->rta_type); 219 *perror = ENOTSUP; 220 return (NULL); 221 } 222 return (NULL); 223 } 224 225 int 226 nlattr_get_ip(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 227 { 228 int error = 0; 229 230 struct sockaddr *sa = parse_rta_ip((struct rtattr *)nla, npt, &error); 231 232 *((struct sockaddr **)target) = sa; 233 return (error); 234 } 235 236 static struct sockaddr * 237 parse_rta_via(struct rtattr *rta, struct nl_pstate *npt, int *perror) 238 { 239 struct rtvia *via = NL_RTA_DATA(rta); 240 int data_len = NL_RTA_DATA_LEN(rta); 241 242 if (__predict_false(data_len) < sizeof(struct rtvia)) { 243 NLMSG_REPORT_ERR_MSG(npt, "undersized RTA_VIA(%d) attr: len %d", 244 rta->rta_type, data_len); 245 *perror = EINVAL; 246 return (NULL); 247 } 248 data_len -= offsetof(struct rtvia, rtvia_addr); 249 250 switch (via->rtvia_family) { 251 case AF_INET: 252 if (__predict_false(data_len < sizeof(struct in_addr))) { 253 *perror = EINVAL; 254 return (NULL); 255 } 256 return (parse_rta_ip4(via->rtvia_addr, npt, perror)); 257 case AF_INET6: 258 if (__predict_false(data_len < sizeof(struct in6_addr))) { 259 *perror = EINVAL; 260 return (NULL); 261 } 262 return (parse_rta_ip6(via->rtvia_addr, npt, perror)); 263 default: 264 *perror = ENOTSUP; 265 return (NULL); 266 } 267 } 268 269 int 270 nlattr_get_ipvia(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 271 { 272 int error = 0; 273 274 struct sockaddr *sa = parse_rta_via((struct rtattr *)nla, npt, &error); 275 276 *((struct sockaddr **)target) = sa; 277 return (error); 278 } 279 280 281 int 282 nlattr_get_uint16(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 283 { 284 if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint16_t))) { 285 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", 286 nla->nla_type, NLA_DATA_LEN(nla)); 287 return (EINVAL); 288 } 289 *((uint16_t *)target) = *((const uint16_t *)NL_RTA_DATA_CONST(nla)); 290 return (0); 291 } 292 293 int 294 nlattr_get_uint32(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 295 { 296 if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint32_t))) { 297 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", 298 nla->nla_type, NLA_DATA_LEN(nla)); 299 return (EINVAL); 300 } 301 *((uint32_t *)target) = *((const uint32_t *)NL_RTA_DATA_CONST(nla)); 302 return (0); 303 } 304 305 int 306 nlattr_get_uint64(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 307 { 308 if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint64_t))) { 309 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint64", 310 nla->nla_type, NLA_DATA_LEN(nla)); 311 return (EINVAL); 312 } 313 memcpy(target, NL_RTA_DATA_CONST(nla), sizeof(uint64_t)); 314 return (0); 315 } 316 317 static int 318 nlattr_get_ifp_internal(struct nlattr *nla, struct nl_pstate *npt, 319 void *target, bool zero_ok) 320 { 321 if (__predict_false(NLA_DATA_LEN(nla) != sizeof(uint32_t))) { 322 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not uint32", 323 nla->nla_type, NLA_DATA_LEN(nla)); 324 return (EINVAL); 325 } 326 uint32_t ifindex = *((const uint32_t *)NLA_DATA_CONST(nla)); 327 328 if (ifindex == 0 && zero_ok) { 329 *((struct ifnet **)target) = NULL; 330 return (0); 331 } 332 333 NET_EPOCH_ASSERT(); 334 335 struct ifnet *ifp = ifnet_byindex(ifindex); 336 if (__predict_false(ifp == NULL)) { 337 NLMSG_REPORT_ERR_MSG(npt, "nla type %d: ifindex %u invalid", 338 nla->nla_type, ifindex); 339 return (ENOENT); 340 } 341 *((struct ifnet **)target) = ifp; 342 NL_LOG(LOG_DEBUG3, "nla type %d: ifindex %u -> %s", nla->nla_type, 343 ifindex, if_name(ifp)); 344 345 return (0); 346 } 347 348 int 349 nlattr_get_ifp(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 350 { 351 return (nlattr_get_ifp_internal(nla, npt, target, false)); 352 } 353 354 int 355 nlattr_get_ifpz(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 356 { 357 return (nlattr_get_ifp_internal(nla, npt, target, true)); 358 } 359 360 int 361 nlattr_get_string(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 362 { 363 int maxlen = NLA_DATA_LEN(nla); 364 365 if (__predict_false(strnlen((char *)NLA_DATA(nla), maxlen) >= maxlen)) { 366 NLMSG_REPORT_ERR_MSG(npt, "nla type %d size(%u) is not NULL-terminated", 367 nla->nla_type, maxlen); 368 return (EINVAL); 369 } 370 371 *((char **)target) = (char *)NLA_DATA(nla); 372 return (0); 373 } 374 375 int 376 nlattr_get_stringn(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 377 { 378 int maxlen = NLA_DATA_LEN(nla); 379 380 char *buf = npt_alloc(npt, maxlen + 1); 381 if (buf == NULL) 382 return (ENOMEM); 383 buf[maxlen] = '\0'; 384 memcpy(buf, NLA_DATA(nla), maxlen); 385 386 *((char **)target) = buf; 387 return (0); 388 } 389 int 390 nlattr_get_nla(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 391 { 392 NL_LOG(LOG_DEBUG3, "STORING %p len %d", nla, nla->nla_len); 393 *((struct nlattr **)target) = nla; 394 return (0); 395 } 396 397 int 398 nlattr_get_nested(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 399 { 400 const struct nlhdr_parser *p = (const struct nlhdr_parser *)arg; 401 int error; 402 403 /* Assumes target points to the beginning of the structure */ 404 error = nl_parse_header(NLA_DATA(nla), NLA_DATA_LEN(nla), p, npt, target); 405 return (error); 406 } 407 408 int 409 nlf_get_ifp(void *src, struct nl_pstate *npt, void *target) 410 { 411 int ifindex = *((const int *)src); 412 413 NET_EPOCH_ASSERT(); 414 415 struct ifnet *ifp = ifnet_byindex(ifindex); 416 if (ifp == NULL) { 417 NL_LOG(LOG_DEBUG, "ifindex %u invalid", ifindex); 418 return (ENOENT); 419 } 420 *((struct ifnet **)target) = ifp; 421 422 return (0); 423 } 424 425 int 426 nlf_get_ifpz(void *src, struct nl_pstate *npt, void *target) 427 { 428 int ifindex = *((const int *)src); 429 430 NET_EPOCH_ASSERT(); 431 432 struct ifnet *ifp = ifnet_byindex(ifindex); 433 if (ifindex != 0 && ifp == NULL) { 434 NL_LOG(LOG_DEBUG, "ifindex %u invalid", ifindex); 435 return (ENOENT); 436 } 437 *((struct ifnet **)target) = ifp; 438 439 return (0); 440 } 441 442 int 443 nlf_get_u8(void *src, struct nl_pstate *npt, void *target) 444 { 445 uint8_t val = *((const uint8_t *)src); 446 447 *((uint8_t *)target) = val; 448 449 return (0); 450 } 451 452 int 453 nlf_get_u8_u32(void *src, struct nl_pstate *npt, void *target) 454 { 455 *((uint32_t *)target) = *((const uint8_t *)src); 456 return (0); 457 } 458 459 int 460 nlf_get_u16(void *src, struct nl_pstate *npt, void *target) 461 { 462 *((uint16_t *)target) = *((const uint16_t *)src); 463 return (0); 464 } 465 466 int 467 nlf_get_u32(void *src, struct nl_pstate *npt, void *target) 468 { 469 *((uint32_t *)target) = *((const uint32_t *)src); 470 return (0); 471 } 472 473