| 1 | /* |
| 2 | * Packet matching code. |
| 3 | * |
| 4 | * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
| 5 | * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> |
| 6 | * Copyright (c) 2006-2010 Patrick McHardy <kaber@trash.net> |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
| 9 | * it under the terms of the GNU General Public License version 2 as |
| 10 | * published by the Free Software Foundation. |
| 11 | */ |
| 12 | |
| 13 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 14 | |
| 15 | #include <linux/kernel.h> |
| 16 | #include <linux/capability.h> |
| 17 | #include <linux/in.h> |
| 18 | #include <linux/skbuff.h> |
| 19 | #include <linux/kmod.h> |
| 20 | #include <linux/vmalloc.h> |
| 21 | #include <linux/netdevice.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/poison.h> |
| 24 | #include <linux/icmpv6.h> |
| 25 | #include <net/ipv6.h> |
| 26 | #include <net/compat.h> |
| 27 | #include <linux/uaccess.h> |
| 28 | #include <linux/mutex.h> |
| 29 | #include <linux/proc_fs.h> |
| 30 | #include <linux/err.h> |
| 31 | #include <linux/cpumask.h> |
| 32 | |
| 33 | #include <linux/netfilter_ipv6/ip6_tables.h> |
| 34 | #include <linux/netfilter/x_tables.h> |
| 35 | #include <net/netfilter/nf_log.h> |
| 36 | #include "../../netfilter/xt_repldata.h" |
| 37 | |
| 38 | MODULE_LICENSE("GPL"); |
| 39 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); |
| 40 | MODULE_DESCRIPTION("IPv6 packet filter"); |
| 41 | |
| 42 | void *ip6t_alloc_initial_table(const struct xt_table *info) |
| 43 | { |
| 44 | return xt_alloc_initial_table(ip6t, IP6T); |
| 45 | } |
| 46 | EXPORT_SYMBOL_GPL(ip6t_alloc_initial_table); |
| 47 | |
| 48 | /* Returns whether matches rule or not. */ |
| 49 | /* Performance critical - called for every packet */ |
| 50 | static inline bool |
| 51 | ip6_packet_match(const struct sk_buff *skb, |
| 52 | const char *indev, |
| 53 | const char *outdev, |
| 54 | const struct ip6t_ip6 *ip6info, |
| 55 | unsigned int *protoff, |
| 56 | int *fragoff, bool *hotdrop) |
| 57 | { |
| 58 | unsigned long ret; |
| 59 | const struct ipv6hdr *ipv6 = ipv6_hdr(skb); |
| 60 | |
| 61 | if (NF_INVF(ip6info, IP6T_INV_SRCIP, |
| 62 | ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk, |
| 63 | &ip6info->src)) || |
| 64 | NF_INVF(ip6info, IP6T_INV_DSTIP, |
| 65 | ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk, |
| 66 | &ip6info->dst))) |
| 67 | return false; |
| 68 | |
| 69 | ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask); |
| 70 | |
| 71 | if (NF_INVF(ip6info, IP6T_INV_VIA_IN, ret != 0)) |
| 72 | return false; |
| 73 | |
| 74 | ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask); |
| 75 | |
| 76 | if (NF_INVF(ip6info, IP6T_INV_VIA_OUT, ret != 0)) |
| 77 | return false; |
| 78 | |
| 79 | /* ... might want to do something with class and flowlabel here ... */ |
| 80 | |
| 81 | /* look for the desired protocol header */ |
| 82 | if (ip6info->flags & IP6T_F_PROTO) { |
| 83 | int protohdr; |
| 84 | unsigned short _frag_off; |
| 85 | |
| 86 | protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off, NULL); |
| 87 | if (protohdr < 0) { |
| 88 | if (_frag_off == 0) |
| 89 | *hotdrop = true; |
| 90 | return false; |
| 91 | } |
| 92 | *fragoff = _frag_off; |
| 93 | |
| 94 | if (ip6info->proto == protohdr) { |
| 95 | if (ip6info->invflags & IP6T_INV_PROTO) |
| 96 | return false; |
| 97 | |
| 98 | return true; |
| 99 | } |
| 100 | |
| 101 | /* We need match for the '-p all', too! */ |
| 102 | if ((ip6info->proto != 0) && |
| 103 | !(ip6info->invflags & IP6T_INV_PROTO)) |
| 104 | return false; |
| 105 | } |
| 106 | return true; |
| 107 | } |
| 108 | |
| 109 | /* should be ip6 safe */ |
| 110 | static bool |
| 111 | ip6_checkentry(const struct ip6t_ip6 *ipv6) |
| 112 | { |
| 113 | if (ipv6->flags & ~IP6T_F_MASK) |
| 114 | return false; |
| 115 | if (ipv6->invflags & ~IP6T_INV_MASK) |
| 116 | return false; |
| 117 | |
| 118 | return true; |
| 119 | } |
| 120 | |
| 121 | static unsigned int |
| 122 | ip6t_error(struct sk_buff *skb, const struct xt_action_param *par) |
| 123 | { |
| 124 | net_info_ratelimited("error: `%s'\n", (const char *)par->targinfo); |
| 125 | |
| 126 | return NF_DROP; |
| 127 | } |
| 128 | |
| 129 | static inline struct ip6t_entry * |
| 130 | get_entry(const void *base, unsigned int offset) |
| 131 | { |
| 132 | return (struct ip6t_entry *)(base + offset); |
| 133 | } |
| 134 | |
| 135 | /* All zeroes == unconditional rule. */ |
| 136 | /* Mildly perf critical (only if packet tracing is on) */ |
| 137 | static inline bool unconditional(const struct ip6t_entry *e) |
| 138 | { |
| 139 | static const struct ip6t_ip6 uncond; |
| 140 | |
| 141 | return e->target_offset == sizeof(struct ip6t_entry) && |
| 142 | memcmp(&e->ipv6, &uncond, sizeof(uncond)) == 0; |
| 143 | } |
| 144 | |
| 145 | static inline const struct xt_entry_target * |
| 146 | ip6t_get_target_c(const struct ip6t_entry *e) |
| 147 | { |
| 148 | return ip6t_get_target((struct ip6t_entry *)e); |
| 149 | } |
| 150 | |
| 151 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) |
| 152 | /* This cries for unification! */ |
| 153 | static const char *const hooknames[] = { |
| 154 | [NF_INET_PRE_ROUTING] = "PREROUTING", |
| 155 | [NF_INET_LOCAL_IN] = "INPUT", |
| 156 | [NF_INET_FORWARD] = "FORWARD", |
| 157 | [NF_INET_LOCAL_OUT] = "OUTPUT", |
| 158 | [NF_INET_POST_ROUTING] = "POSTROUTING", |
| 159 | }; |
| 160 | |
| 161 | enum nf_ip_trace_comments { |
| 162 | NF_IP6_TRACE_COMMENT_RULE, |
| 163 | NF_IP6_TRACE_COMMENT_RETURN, |
| 164 | NF_IP6_TRACE_COMMENT_POLICY, |
| 165 | }; |
| 166 | |
| 167 | static const char *const comments[] = { |
| 168 | [NF_IP6_TRACE_COMMENT_RULE] = "rule", |
| 169 | [NF_IP6_TRACE_COMMENT_RETURN] = "return", |
| 170 | [NF_IP6_TRACE_COMMENT_POLICY] = "policy", |
| 171 | }; |
| 172 | |
| 173 | static const struct nf_loginfo trace_loginfo = { |
| 174 | .type = NF_LOG_TYPE_LOG, |
| 175 | .u = { |
| 176 | .log = { |
| 177 | .level = LOGLEVEL_WARNING, |
| 178 | .logflags = NF_LOG_DEFAULT_MASK, |
| 179 | }, |
| 180 | }, |
| 181 | }; |
| 182 | |
| 183 | /* Mildly perf critical (only if packet tracing is on) */ |
| 184 | static inline int |
| 185 | get_chainname_rulenum(const struct ip6t_entry *s, const struct ip6t_entry *e, |
| 186 | const char *hookname, const char **chainname, |
| 187 | const char **comment, unsigned int *rulenum) |
| 188 | { |
| 189 | const struct xt_standard_target *t = (void *)ip6t_get_target_c(s); |
| 190 | |
| 191 | if (strcmp(t->target.u.kernel.target->name, XT_ERROR_TARGET) == 0) { |
| 192 | /* Head of user chain: ERROR target with chainname */ |
| 193 | *chainname = t->target.data; |
| 194 | (*rulenum) = 0; |
| 195 | } else if (s == e) { |
| 196 | (*rulenum)++; |
| 197 | |
| 198 | if (unconditional(s) && |
| 199 | strcmp(t->target.u.kernel.target->name, |
| 200 | XT_STANDARD_TARGET) == 0 && |
| 201 | t->verdict < 0) { |
| 202 | /* Tail of chains: STANDARD target (return/policy) */ |
| 203 | *comment = *chainname == hookname |
| 204 | ? comments[NF_IP6_TRACE_COMMENT_POLICY] |
| 205 | : comments[NF_IP6_TRACE_COMMENT_RETURN]; |
| 206 | } |
| 207 | return 1; |
| 208 | } else |
| 209 | (*rulenum)++; |
| 210 | |
| 211 | return 0; |
| 212 | } |
| 213 | |
| 214 | static void trace_packet(struct net *net, |
| 215 | const struct sk_buff *skb, |
| 216 | unsigned int hook, |
| 217 | const struct net_device *in, |
| 218 | const struct net_device *out, |
| 219 | const char *tablename, |
| 220 | const struct xt_table_info *private, |
| 221 | const struct ip6t_entry *e) |
| 222 | { |
| 223 | const struct ip6t_entry *root; |
| 224 | const char *hookname, *chainname, *comment; |
| 225 | const struct ip6t_entry *iter; |
| 226 | unsigned int rulenum = 0; |
| 227 | |
| 228 | root = get_entry(private->entries, private->hook_entry[hook]); |
| 229 | |
| 230 | hookname = chainname = hooknames[hook]; |
| 231 | comment = comments[NF_IP6_TRACE_COMMENT_RULE]; |
| 232 | |
| 233 | xt_entry_foreach(iter, root, private->size - private->hook_entry[hook]) |
| 234 | if (get_chainname_rulenum(iter, e, hookname, |
| 235 | &chainname, &comment, &rulenum) != 0) |
| 236 | break; |
| 237 | |
| 238 | nf_log_trace(net, AF_INET6, hook, skb, in, out, &trace_loginfo, |
| 239 | "TRACE: %s:%s:%s:%u ", |
| 240 | tablename, chainname, comment, rulenum); |
| 241 | } |
| 242 | #endif |
| 243 | |
| 244 | static inline struct ip6t_entry * |
| 245 | ip6t_next_entry(const struct ip6t_entry *entry) |
| 246 | { |
| 247 | return (void *)entry + entry->next_offset; |
| 248 | } |
| 249 | |
| 250 | /* Returns one of the generic firewall policies, like NF_ACCEPT. */ |
| 251 | unsigned int |
| 252 | ip6t_do_table(struct sk_buff *skb, |
| 253 | const struct nf_hook_state *state, |
| 254 | struct xt_table *table) |
| 255 | { |
| 256 | unsigned int hook = state->hook; |
| 257 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
| 258 | /* Initializing verdict to NF_DROP keeps gcc happy. */ |
| 259 | unsigned int verdict = NF_DROP; |
| 260 | const char *indev, *outdev; |
| 261 | const void *table_base; |
| 262 | struct ip6t_entry *e, **jumpstack; |
| 263 | unsigned int stackidx, cpu; |
| 264 | const struct xt_table_info *private; |
| 265 | struct xt_action_param acpar; |
| 266 | unsigned int addend; |
| 267 | |
| 268 | /* Initialization */ |
| 269 | stackidx = 0; |
| 270 | indev = state->in ? state->in->name : nulldevname; |
| 271 | outdev = state->out ? state->out->name : nulldevname; |
| 272 | /* We handle fragments by dealing with the first fragment as |
| 273 | * if it was a normal packet. All other fragments are treated |
| 274 | * normally, except that they will NEVER match rules that ask |
| 275 | * things we don't know, ie. tcp syn flag or ports). If the |
| 276 | * rule is also a fragment-specific rule, non-fragments won't |
| 277 | * match it. */ |
| 278 | acpar.hotdrop = false; |
| 279 | acpar.state = state; |
| 280 | |
| 281 | WARN_ON(!(table->valid_hooks & (1 << hook))); |
| 282 | |
| 283 | local_bh_disable(); |
| 284 | addend = xt_write_recseq_begin(); |
| 285 | private = table->private; |
| 286 | /* |
| 287 | * Ensure we load private-> members after we've fetched the base |
| 288 | * pointer. |
| 289 | */ |
| 290 | smp_read_barrier_depends(); |
| 291 | cpu = smp_processor_id(); |
| 292 | table_base = private->entries; |
| 293 | jumpstack = (struct ip6t_entry **)private->jumpstack[cpu]; |
| 294 | |
| 295 | /* Switch to alternate jumpstack if we're being invoked via TEE. |
| 296 | * TEE issues XT_CONTINUE verdict on original skb so we must not |
| 297 | * clobber the jumpstack. |
| 298 | * |
| 299 | * For recursion via REJECT or SYNPROXY the stack will be clobbered |
| 300 | * but it is no problem since absolute verdict is issued by these. |
| 301 | */ |
| 302 | if (static_key_false(&xt_tee_enabled)) |
| 303 | jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated); |
| 304 | |
| 305 | e = get_entry(table_base, private->hook_entry[hook]); |
| 306 | |
| 307 | do { |
| 308 | const struct xt_entry_target *t; |
| 309 | const struct xt_entry_match *ematch; |
| 310 | struct xt_counters *counter; |
| 311 | |
| 312 | WARN_ON(!e); |
| 313 | acpar.thoff = 0; |
| 314 | if (!ip6_packet_match(skb, indev, outdev, &e->ipv6, |
| 315 | &acpar.thoff, &acpar.fragoff, &acpar.hotdrop)) { |
| 316 | no_match: |
| 317 | e = ip6t_next_entry(e); |
| 318 | continue; |
| 319 | } |
| 320 | |
| 321 | xt_ematch_foreach(ematch, e) { |
| 322 | acpar.match = ematch->u.kernel.match; |
| 323 | acpar.matchinfo = ematch->data; |
| 324 | if (!acpar.match->match(skb, &acpar)) |
| 325 | goto no_match; |
| 326 | } |
| 327 | |
| 328 | counter = xt_get_this_cpu_counter(&e->counters); |
| 329 | ADD_COUNTER(*counter, skb->len, 1); |
| 330 | |
| 331 | t = ip6t_get_target_c(e); |
| 332 | WARN_ON(!t->u.kernel.target); |
| 333 | |
| 334 | #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) |
| 335 | /* The packet is traced: log it */ |
| 336 | if (unlikely(skb->nf_trace)) |
| 337 | trace_packet(state->net, skb, hook, state->in, |
| 338 | state->out, table->name, private, e); |
| 339 | #endif |
| 340 | /* Standard target? */ |
| 341 | if (!t->u.kernel.target->target) { |
| 342 | int v; |
| 343 | |
| 344 | v = ((struct xt_standard_target *)t)->verdict; |
| 345 | if (v < 0) { |
| 346 | /* Pop from stack? */ |
| 347 | if (v != XT_RETURN) { |
| 348 | verdict = (unsigned int)(-v) - 1; |
| 349 | break; |
| 350 | } |
| 351 | if (stackidx == 0) |
| 352 | e = get_entry(table_base, |
| 353 | private->underflow[hook]); |
| 354 | else |
| 355 | e = ip6t_next_entry(jumpstack[--stackidx]); |
| 356 | continue; |
| 357 | } |
| 358 | if (table_base + v != ip6t_next_entry(e) && |
| 359 | !(e->ipv6.flags & IP6T_F_GOTO)) { |
| 360 | if (unlikely(stackidx >= private->stacksize)) { |
| 361 | verdict = NF_DROP; |
| 362 | break; |
| 363 | } |
| 364 | jumpstack[stackidx++] = e; |
| 365 | } |
| 366 | |
| 367 | e = get_entry(table_base, v); |
| 368 | continue; |
| 369 | } |
| 370 | |
| 371 | acpar.target = t->u.kernel.target; |
| 372 | acpar.targinfo = t->data; |
| 373 | |
| 374 | verdict = t->u.kernel.target->target(skb, &acpar); |
| 375 | if (verdict == XT_CONTINUE) |
| 376 | e = ip6t_next_entry(e); |
| 377 | else |
| 378 | /* Verdict */ |
| 379 | break; |
| 380 | } while (!acpar.hotdrop); |
| 381 | |
| 382 | xt_write_recseq_end(addend); |
| 383 | local_bh_enable(); |
| 384 | |
| 385 | if (acpar.hotdrop) |
| 386 | return NF_DROP; |
| 387 | else return verdict; |
| 388 | } |
| 389 | |
| 390 | /* Figures out from what hook each rule can be called: returns 0 if |
| 391 | there are loops. Puts hook bitmask in comefrom. */ |
| 392 | static int |
| 393 | mark_source_chains(const struct xt_table_info *newinfo, |
| 394 | unsigned int valid_hooks, void *entry0, |
| 395 | unsigned int *offsets) |
| 396 | { |
| 397 | unsigned int hook; |
| 398 | |
| 399 | /* No recursion; use packet counter to save back ptrs (reset |
| 400 | to 0 as we leave), and comefrom to save source hook bitmask */ |
| 401 | for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) { |
| 402 | unsigned int pos = newinfo->hook_entry[hook]; |
| 403 | struct ip6t_entry *e = entry0 + pos; |
| 404 | |
| 405 | if (!(valid_hooks & (1 << hook))) |
| 406 | continue; |
| 407 | |
| 408 | /* Set initial back pointer. */ |
| 409 | e->counters.pcnt = pos; |
| 410 | |
| 411 | for (;;) { |
| 412 | const struct xt_standard_target *t |
| 413 | = (void *)ip6t_get_target_c(e); |
| 414 | int visited = e->comefrom & (1 << hook); |
| 415 | |
| 416 | if (e->comefrom & (1 << NF_INET_NUMHOOKS)) |
| 417 | return 0; |
| 418 | |
| 419 | e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS)); |
| 420 | |
| 421 | /* Unconditional return/END. */ |
| 422 | if ((unconditional(e) && |
| 423 | (strcmp(t->target.u.user.name, |
| 424 | XT_STANDARD_TARGET) == 0) && |
| 425 | t->verdict < 0) || visited) { |
| 426 | unsigned int oldpos, size; |
| 427 | |
| 428 | if ((strcmp(t->target.u.user.name, |
| 429 | XT_STANDARD_TARGET) == 0) && |
| 430 | t->verdict < -NF_MAX_VERDICT - 1) |
| 431 | return 0; |
| 432 | |
| 433 | /* Return: backtrack through the last |
| 434 | big jump. */ |
| 435 | do { |
| 436 | e->comefrom ^= (1<<NF_INET_NUMHOOKS); |
| 437 | oldpos = pos; |
| 438 | pos = e->counters.pcnt; |
| 439 | e->counters.pcnt = 0; |
| 440 | |
| 441 | /* We're at the start. */ |
| 442 | if (pos == oldpos) |
| 443 | goto next; |
| 444 | |
| 445 | e = entry0 + pos; |
| 446 | } while (oldpos == pos + e->next_offset); |
| 447 | |
| 448 | /* Move along one */ |
| 449 | size = e->next_offset; |
| 450 | e = entry0 + pos + size; |
| 451 | if (pos + size >= newinfo->size) |
| 452 | return 0; |
| 453 | e->counters.pcnt = pos; |
| 454 | pos += size; |
| 455 | } else { |
| 456 | int newpos = t->verdict; |
| 457 | |
| 458 | if (strcmp(t->target.u.user.name, |
| 459 | XT_STANDARD_TARGET) == 0 && |
| 460 | newpos >= 0) { |
| 461 | /* This a jump; chase it. */ |
| 462 | if (!xt_find_jump_offset(offsets, newpos, |
| 463 | newinfo->number)) |
| 464 | return 0; |
| 465 | e = entry0 + newpos; |
| 466 | } else { |
| 467 | /* ... this is a fallthru */ |
| 468 | newpos = pos + e->next_offset; |
| 469 | if (newpos >= newinfo->size) |
| 470 | return 0; |
| 471 | } |
| 472 | e = entry0 + newpos; |
| 473 | e->counters.pcnt = pos; |
| 474 | pos = newpos; |
| 475 | } |
| 476 | } |
| 477 | next: ; |
| 478 | } |
| 479 | return 1; |
| 480 | } |
| 481 | |
| 482 | static void cleanup_match(struct xt_entry_match *m, struct net *net) |
| 483 | { |
| 484 | struct xt_mtdtor_param par; |
| 485 | |
| 486 | par.net = net; |
| 487 | par.match = m->u.kernel.match; |
| 488 | par.matchinfo = m->data; |
| 489 | par.family = NFPROTO_IPV6; |
| 490 | if (par.match->destroy != NULL) |
| 491 | par.match->destroy(&par); |
| 492 | module_put(par.match->me); |
| 493 | } |
| 494 | |
| 495 | static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par) |
| 496 | { |
| 497 | const struct ip6t_ip6 *ipv6 = par->entryinfo; |
| 498 | |
| 499 | par->match = m->u.kernel.match; |
| 500 | par->matchinfo = m->data; |
| 501 | |
| 502 | return xt_check_match(par, m->u.match_size - sizeof(*m), |
| 503 | ipv6->proto, ipv6->invflags & IP6T_INV_PROTO); |
| 504 | } |
| 505 | |
| 506 | static int |
| 507 | find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par) |
| 508 | { |
| 509 | struct xt_match *match; |
| 510 | int ret; |
| 511 | |
| 512 | match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name, |
| 513 | m->u.user.revision); |
| 514 | if (IS_ERR(match)) |
| 515 | return PTR_ERR(match); |
| 516 | |
| 517 | m->u.kernel.match = match; |
| 518 | |
| 519 | ret = check_match(m, par); |
| 520 | if (ret) |
| 521 | goto err; |
| 522 | |
| 523 | return 0; |
| 524 | err: |
| 525 | module_put(m->u.kernel.match->me); |
| 526 | return ret; |
| 527 | } |
| 528 | |
| 529 | static int check_target(struct ip6t_entry *e, struct net *net, const char *name) |
| 530 | { |
| 531 | struct xt_entry_target *t = ip6t_get_target(e); |
| 532 | struct xt_tgchk_param par = { |
| 533 | .net = net, |
| 534 | .table = name, |
| 535 | .entryinfo = e, |
| 536 | .target = t->u.kernel.target, |
| 537 | .targinfo = t->data, |
| 538 | .hook_mask = e->comefrom, |
| 539 | .family = NFPROTO_IPV6, |
| 540 | }; |
| 541 | |
| 542 | t = ip6t_get_target(e); |
| 543 | return xt_check_target(&par, t->u.target_size - sizeof(*t), |
| 544 | e->ipv6.proto, |
| 545 | e->ipv6.invflags & IP6T_INV_PROTO); |
| 546 | } |
| 547 | |
| 548 | static int |
| 549 | find_check_entry(struct ip6t_entry *e, struct net *net, const char *name, |
| 550 | unsigned int size, |
| 551 | struct xt_percpu_counter_alloc_state *alloc_state) |
| 552 | { |
| 553 | struct xt_entry_target *t; |
| 554 | struct xt_target *target; |
| 555 | int ret; |
| 556 | unsigned int j; |
| 557 | struct xt_mtchk_param mtpar; |
| 558 | struct xt_entry_match *ematch; |
| 559 | |
| 560 | if (!xt_percpu_counter_alloc(alloc_state, &e->counters)) |
| 561 | return -ENOMEM; |
| 562 | |
| 563 | j = 0; |
| 564 | memset(&mtpar, 0, sizeof(mtpar)); |
| 565 | mtpar.net = net; |
| 566 | mtpar.table = name; |
| 567 | mtpar.entryinfo = &e->ipv6; |
| 568 | mtpar.hook_mask = e->comefrom; |
| 569 | mtpar.family = NFPROTO_IPV6; |
| 570 | xt_ematch_foreach(ematch, e) { |
| 571 | ret = find_check_match(ematch, &mtpar); |
| 572 | if (ret != 0) |
| 573 | goto cleanup_matches; |
| 574 | ++j; |
| 575 | } |
| 576 | |
| 577 | t = ip6t_get_target(e); |
| 578 | target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name, |
| 579 | t->u.user.revision); |
| 580 | if (IS_ERR(target)) { |
| 581 | ret = PTR_ERR(target); |
| 582 | goto cleanup_matches; |
| 583 | } |
| 584 | t->u.kernel.target = target; |
| 585 | |
| 586 | ret = check_target(e, net, name); |
| 587 | if (ret) |
| 588 | goto err; |
| 589 | return 0; |
| 590 | err: |
| 591 | module_put(t->u.kernel.target->me); |
| 592 | cleanup_matches: |
| 593 | xt_ematch_foreach(ematch, e) { |
| 594 | if (j-- == 0) |
| 595 | break; |
| 596 | cleanup_match(ematch, net); |
| 597 | } |
| 598 | |
| 599 | xt_percpu_counter_free(&e->counters); |
| 600 | |
| 601 | return ret; |
| 602 | } |
| 603 | |
| 604 | static bool check_underflow(const struct ip6t_entry *e) |
| 605 | { |
| 606 | const struct xt_entry_target *t; |
| 607 | unsigned int verdict; |
| 608 | |
| 609 | if (!unconditional(e)) |
| 610 | return false; |
| 611 | t = ip6t_get_target_c(e); |
| 612 | if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0) |
| 613 | return false; |
| 614 | verdict = ((struct xt_standard_target *)t)->verdict; |
| 615 | verdict = -verdict - 1; |
| 616 | return verdict == NF_DROP || verdict == NF_ACCEPT; |
| 617 | } |
| 618 | |
| 619 | static int |
| 620 | check_entry_size_and_hooks(struct ip6t_entry *e, |
| 621 | struct xt_table_info *newinfo, |
| 622 | const unsigned char *base, |
| 623 | const unsigned char *limit, |
| 624 | const unsigned int *hook_entries, |
| 625 | const unsigned int *underflows, |
| 626 | unsigned int valid_hooks) |
| 627 | { |
| 628 | unsigned int h; |
| 629 | int err; |
| 630 | |
| 631 | if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 || |
| 632 | (unsigned char *)e + sizeof(struct ip6t_entry) >= limit || |
| 633 | (unsigned char *)e + e->next_offset > limit) |
| 634 | return -EINVAL; |
| 635 | |
| 636 | if (e->next_offset |
| 637 | < sizeof(struct ip6t_entry) + sizeof(struct xt_entry_target)) |
| 638 | return -EINVAL; |
| 639 | |
| 640 | if (!ip6_checkentry(&e->ipv6)) |
| 641 | return -EINVAL; |
| 642 | |
| 643 | err = xt_check_entry_offsets(e, e->elems, e->target_offset, |
| 644 | e->next_offset); |
| 645 | if (err) |
| 646 | return err; |
| 647 | |
| 648 | /* Check hooks & underflows */ |
| 649 | for (h = 0; h < NF_INET_NUMHOOKS; h++) { |
| 650 | if (!(valid_hooks & (1 << h))) |
| 651 | continue; |
| 652 | if ((unsigned char *)e - base == hook_entries[h]) |
| 653 | newinfo->hook_entry[h] = hook_entries[h]; |
| 654 | if ((unsigned char *)e - base == underflows[h]) { |
| 655 | if (!check_underflow(e)) |
| 656 | return -EINVAL; |
| 657 | |
| 658 | newinfo->underflow[h] = underflows[h]; |
| 659 | } |
| 660 | } |
| 661 | |
| 662 | /* Clear counters and comefrom */ |
| 663 | e->counters = ((struct xt_counters) { 0, 0 }); |
| 664 | e->comefrom = 0; |
| 665 | return 0; |
| 666 | } |
| 667 | |
| 668 | static void cleanup_entry(struct ip6t_entry *e, struct net *net) |
| 669 | { |
| 670 | struct xt_tgdtor_param par; |
| 671 | struct xt_entry_target *t; |
| 672 | struct xt_entry_match *ematch; |
| 673 | |
| 674 | /* Cleanup all matches */ |
| 675 | xt_ematch_foreach(ematch, e) |
| 676 | cleanup_match(ematch, net); |
| 677 | t = ip6t_get_target(e); |
| 678 | |
| 679 | par.net = net; |
| 680 | par.target = t->u.kernel.target; |
| 681 | par.targinfo = t->data; |
| 682 | par.family = NFPROTO_IPV6; |
| 683 | if (par.target->destroy != NULL) |
| 684 | par.target->destroy(&par); |
| 685 | module_put(par.target->me); |
| 686 | xt_percpu_counter_free(&e->counters); |
| 687 | } |
| 688 | |
| 689 | /* Checks and translates the user-supplied table segment (held in |
| 690 | newinfo) */ |
| 691 | static int |
| 692 | translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, |
| 693 | const struct ip6t_replace *repl) |
| 694 | { |
| 695 | struct xt_percpu_counter_alloc_state alloc_state = { 0 }; |
| 696 | struct ip6t_entry *iter; |
| 697 | unsigned int *offsets; |
| 698 | unsigned int i; |
| 699 | int ret = 0; |
| 700 | |
| 701 | newinfo->size = repl->size; |
| 702 | newinfo->number = repl->num_entries; |
| 703 | |
| 704 | /* Init all hooks to impossible value. */ |
| 705 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 706 | newinfo->hook_entry[i] = 0xFFFFFFFF; |
| 707 | newinfo->underflow[i] = 0xFFFFFFFF; |
| 708 | } |
| 709 | |
| 710 | offsets = xt_alloc_entry_offsets(newinfo->number); |
| 711 | if (!offsets) |
| 712 | return -ENOMEM; |
| 713 | i = 0; |
| 714 | /* Walk through entries, checking offsets. */ |
| 715 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 716 | ret = check_entry_size_and_hooks(iter, newinfo, entry0, |
| 717 | entry0 + repl->size, |
| 718 | repl->hook_entry, |
| 719 | repl->underflow, |
| 720 | repl->valid_hooks); |
| 721 | if (ret != 0) |
| 722 | goto out_free; |
| 723 | if (i < repl->num_entries) |
| 724 | offsets[i] = (void *)iter - entry0; |
| 725 | ++i; |
| 726 | if (strcmp(ip6t_get_target(iter)->u.user.name, |
| 727 | XT_ERROR_TARGET) == 0) |
| 728 | ++newinfo->stacksize; |
| 729 | } |
| 730 | |
| 731 | ret = -EINVAL; |
| 732 | if (i != repl->num_entries) |
| 733 | goto out_free; |
| 734 | |
| 735 | /* Check hooks all assigned */ |
| 736 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 737 | /* Only hooks which are valid */ |
| 738 | if (!(repl->valid_hooks & (1 << i))) |
| 739 | continue; |
| 740 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) |
| 741 | goto out_free; |
| 742 | if (newinfo->underflow[i] == 0xFFFFFFFF) |
| 743 | goto out_free; |
| 744 | } |
| 745 | |
| 746 | if (!mark_source_chains(newinfo, repl->valid_hooks, entry0, offsets)) { |
| 747 | ret = -ELOOP; |
| 748 | goto out_free; |
| 749 | } |
| 750 | kvfree(offsets); |
| 751 | |
| 752 | /* Finally, each sanity check must pass */ |
| 753 | i = 0; |
| 754 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 755 | ret = find_check_entry(iter, net, repl->name, repl->size, |
| 756 | &alloc_state); |
| 757 | if (ret != 0) |
| 758 | break; |
| 759 | ++i; |
| 760 | } |
| 761 | |
| 762 | if (ret != 0) { |
| 763 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 764 | if (i-- == 0) |
| 765 | break; |
| 766 | cleanup_entry(iter, net); |
| 767 | } |
| 768 | return ret; |
| 769 | } |
| 770 | |
| 771 | return ret; |
| 772 | out_free: |
| 773 | kvfree(offsets); |
| 774 | return ret; |
| 775 | } |
| 776 | |
| 777 | static void |
| 778 | get_counters(const struct xt_table_info *t, |
| 779 | struct xt_counters counters[]) |
| 780 | { |
| 781 | struct ip6t_entry *iter; |
| 782 | unsigned int cpu; |
| 783 | unsigned int i; |
| 784 | |
| 785 | for_each_possible_cpu(cpu) { |
| 786 | seqcount_t *s = &per_cpu(xt_recseq, cpu); |
| 787 | |
| 788 | i = 0; |
| 789 | xt_entry_foreach(iter, t->entries, t->size) { |
| 790 | struct xt_counters *tmp; |
| 791 | u64 bcnt, pcnt; |
| 792 | unsigned int start; |
| 793 | |
| 794 | tmp = xt_get_per_cpu_counter(&iter->counters, cpu); |
| 795 | do { |
| 796 | start = read_seqcount_begin(s); |
| 797 | bcnt = tmp->bcnt; |
| 798 | pcnt = tmp->pcnt; |
| 799 | } while (read_seqcount_retry(s, start)); |
| 800 | |
| 801 | ADD_COUNTER(counters[i], bcnt, pcnt); |
| 802 | ++i; |
| 803 | cond_resched(); |
| 804 | } |
| 805 | } |
| 806 | } |
| 807 | |
| 808 | static struct xt_counters *alloc_counters(const struct xt_table *table) |
| 809 | { |
| 810 | unsigned int countersize; |
| 811 | struct xt_counters *counters; |
| 812 | const struct xt_table_info *private = table->private; |
| 813 | |
| 814 | /* We need atomic snapshot of counters: rest doesn't change |
| 815 | (other than comefrom, which userspace doesn't care |
| 816 | about). */ |
| 817 | countersize = sizeof(struct xt_counters) * private->number; |
| 818 | counters = vzalloc(countersize); |
| 819 | |
| 820 | if (counters == NULL) |
| 821 | return ERR_PTR(-ENOMEM); |
| 822 | |
| 823 | get_counters(private, counters); |
| 824 | |
| 825 | return counters; |
| 826 | } |
| 827 | |
| 828 | static int |
| 829 | copy_entries_to_user(unsigned int total_size, |
| 830 | const struct xt_table *table, |
| 831 | void __user *userptr) |
| 832 | { |
| 833 | unsigned int off, num; |
| 834 | const struct ip6t_entry *e; |
| 835 | struct xt_counters *counters; |
| 836 | const struct xt_table_info *private = table->private; |
| 837 | int ret = 0; |
| 838 | const void *loc_cpu_entry; |
| 839 | |
| 840 | counters = alloc_counters(table); |
| 841 | if (IS_ERR(counters)) |
| 842 | return PTR_ERR(counters); |
| 843 | |
| 844 | loc_cpu_entry = private->entries; |
| 845 | |
| 846 | /* FIXME: use iterator macros --RR */ |
| 847 | /* ... then go back and fix counters and names */ |
| 848 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ |
| 849 | unsigned int i; |
| 850 | const struct xt_entry_match *m; |
| 851 | const struct xt_entry_target *t; |
| 852 | |
| 853 | e = loc_cpu_entry + off; |
| 854 | if (copy_to_user(userptr + off, e, sizeof(*e))) { |
| 855 | ret = -EFAULT; |
| 856 | goto free_counters; |
| 857 | } |
| 858 | if (copy_to_user(userptr + off |
| 859 | + offsetof(struct ip6t_entry, counters), |
| 860 | &counters[num], |
| 861 | sizeof(counters[num])) != 0) { |
| 862 | ret = -EFAULT; |
| 863 | goto free_counters; |
| 864 | } |
| 865 | |
| 866 | for (i = sizeof(struct ip6t_entry); |
| 867 | i < e->target_offset; |
| 868 | i += m->u.match_size) { |
| 869 | m = (void *)e + i; |
| 870 | |
| 871 | if (xt_match_to_user(m, userptr + off + i)) { |
| 872 | ret = -EFAULT; |
| 873 | goto free_counters; |
| 874 | } |
| 875 | } |
| 876 | |
| 877 | t = ip6t_get_target_c(e); |
| 878 | if (xt_target_to_user(t, userptr + off + e->target_offset)) { |
| 879 | ret = -EFAULT; |
| 880 | goto free_counters; |
| 881 | } |
| 882 | } |
| 883 | |
| 884 | free_counters: |
| 885 | vfree(counters); |
| 886 | return ret; |
| 887 | } |
| 888 | |
| 889 | #ifdef CONFIG_COMPAT |
| 890 | static void compat_standard_from_user(void *dst, const void *src) |
| 891 | { |
| 892 | int v = *(compat_int_t *)src; |
| 893 | |
| 894 | if (v > 0) |
| 895 | v += xt_compat_calc_jump(AF_INET6, v); |
| 896 | memcpy(dst, &v, sizeof(v)); |
| 897 | } |
| 898 | |
| 899 | static int compat_standard_to_user(void __user *dst, const void *src) |
| 900 | { |
| 901 | compat_int_t cv = *(int *)src; |
| 902 | |
| 903 | if (cv > 0) |
| 904 | cv -= xt_compat_calc_jump(AF_INET6, cv); |
| 905 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; |
| 906 | } |
| 907 | |
| 908 | static int compat_calc_entry(const struct ip6t_entry *e, |
| 909 | const struct xt_table_info *info, |
| 910 | const void *base, struct xt_table_info *newinfo) |
| 911 | { |
| 912 | const struct xt_entry_match *ematch; |
| 913 | const struct xt_entry_target *t; |
| 914 | unsigned int entry_offset; |
| 915 | int off, i, ret; |
| 916 | |
| 917 | off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 918 | entry_offset = (void *)e - base; |
| 919 | xt_ematch_foreach(ematch, e) |
| 920 | off += xt_compat_match_offset(ematch->u.kernel.match); |
| 921 | t = ip6t_get_target_c(e); |
| 922 | off += xt_compat_target_offset(t->u.kernel.target); |
| 923 | newinfo->size -= off; |
| 924 | ret = xt_compat_add_offset(AF_INET6, entry_offset, off); |
| 925 | if (ret) |
| 926 | return ret; |
| 927 | |
| 928 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 929 | if (info->hook_entry[i] && |
| 930 | (e < (struct ip6t_entry *)(base + info->hook_entry[i]))) |
| 931 | newinfo->hook_entry[i] -= off; |
| 932 | if (info->underflow[i] && |
| 933 | (e < (struct ip6t_entry *)(base + info->underflow[i]))) |
| 934 | newinfo->underflow[i] -= off; |
| 935 | } |
| 936 | return 0; |
| 937 | } |
| 938 | |
| 939 | static int compat_table_info(const struct xt_table_info *info, |
| 940 | struct xt_table_info *newinfo) |
| 941 | { |
| 942 | struct ip6t_entry *iter; |
| 943 | const void *loc_cpu_entry; |
| 944 | int ret; |
| 945 | |
| 946 | if (!newinfo || !info) |
| 947 | return -EINVAL; |
| 948 | |
| 949 | /* we dont care about newinfo->entries */ |
| 950 | memcpy(newinfo, info, offsetof(struct xt_table_info, entries)); |
| 951 | newinfo->initial_entries = 0; |
| 952 | loc_cpu_entry = info->entries; |
| 953 | ret = xt_compat_init_offsets(AF_INET6, info->number); |
| 954 | if (ret) |
| 955 | return ret; |
| 956 | xt_entry_foreach(iter, loc_cpu_entry, info->size) { |
| 957 | ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo); |
| 958 | if (ret != 0) |
| 959 | return ret; |
| 960 | } |
| 961 | return 0; |
| 962 | } |
| 963 | #endif |
| 964 | |
| 965 | static int get_info(struct net *net, void __user *user, |
| 966 | const int *len, int compat) |
| 967 | { |
| 968 | char name[XT_TABLE_MAXNAMELEN]; |
| 969 | struct xt_table *t; |
| 970 | int ret; |
| 971 | |
| 972 | if (*len != sizeof(struct ip6t_getinfo)) |
| 973 | return -EINVAL; |
| 974 | |
| 975 | if (copy_from_user(name, user, sizeof(name)) != 0) |
| 976 | return -EFAULT; |
| 977 | |
| 978 | name[XT_TABLE_MAXNAMELEN-1] = '\0'; |
| 979 | #ifdef CONFIG_COMPAT |
| 980 | if (compat) |
| 981 | xt_compat_lock(AF_INET6); |
| 982 | #endif |
| 983 | t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), |
| 984 | "ip6table_%s", name); |
| 985 | if (t) { |
| 986 | struct ip6t_getinfo info; |
| 987 | const struct xt_table_info *private = t->private; |
| 988 | #ifdef CONFIG_COMPAT |
| 989 | struct xt_table_info tmp; |
| 990 | |
| 991 | if (compat) { |
| 992 | ret = compat_table_info(private, &tmp); |
| 993 | xt_compat_flush_offsets(AF_INET6); |
| 994 | private = &tmp; |
| 995 | } |
| 996 | #endif |
| 997 | memset(&info, 0, sizeof(info)); |
| 998 | info.valid_hooks = t->valid_hooks; |
| 999 | memcpy(info.hook_entry, private->hook_entry, |
| 1000 | sizeof(info.hook_entry)); |
| 1001 | memcpy(info.underflow, private->underflow, |
| 1002 | sizeof(info.underflow)); |
| 1003 | info.num_entries = private->number; |
| 1004 | info.size = private->size; |
| 1005 | strcpy(info.name, name); |
| 1006 | |
| 1007 | if (copy_to_user(user, &info, *len) != 0) |
| 1008 | ret = -EFAULT; |
| 1009 | else |
| 1010 | ret = 0; |
| 1011 | |
| 1012 | xt_table_unlock(t); |
| 1013 | module_put(t->me); |
| 1014 | } else |
| 1015 | ret = -ENOENT; |
| 1016 | #ifdef CONFIG_COMPAT |
| 1017 | if (compat) |
| 1018 | xt_compat_unlock(AF_INET6); |
| 1019 | #endif |
| 1020 | return ret; |
| 1021 | } |
| 1022 | |
| 1023 | static int |
| 1024 | get_entries(struct net *net, struct ip6t_get_entries __user *uptr, |
| 1025 | const int *len) |
| 1026 | { |
| 1027 | int ret; |
| 1028 | struct ip6t_get_entries get; |
| 1029 | struct xt_table *t; |
| 1030 | |
| 1031 | if (*len < sizeof(get)) |
| 1032 | return -EINVAL; |
| 1033 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) |
| 1034 | return -EFAULT; |
| 1035 | if (*len != sizeof(struct ip6t_get_entries) + get.size) |
| 1036 | return -EINVAL; |
| 1037 | |
| 1038 | get.name[sizeof(get.name) - 1] = '\0'; |
| 1039 | |
| 1040 | t = xt_find_table_lock(net, AF_INET6, get.name); |
| 1041 | if (t) { |
| 1042 | struct xt_table_info *private = t->private; |
| 1043 | if (get.size == private->size) |
| 1044 | ret = copy_entries_to_user(private->size, |
| 1045 | t, uptr->entrytable); |
| 1046 | else |
| 1047 | ret = -EAGAIN; |
| 1048 | |
| 1049 | module_put(t->me); |
| 1050 | xt_table_unlock(t); |
| 1051 | } else |
| 1052 | ret = -ENOENT; |
| 1053 | |
| 1054 | return ret; |
| 1055 | } |
| 1056 | |
| 1057 | static int |
| 1058 | __do_replace(struct net *net, const char *name, unsigned int valid_hooks, |
| 1059 | struct xt_table_info *newinfo, unsigned int num_counters, |
| 1060 | void __user *counters_ptr) |
| 1061 | { |
| 1062 | int ret; |
| 1063 | struct xt_table *t; |
| 1064 | struct xt_table_info *oldinfo; |
| 1065 | struct xt_counters *counters; |
| 1066 | struct ip6t_entry *iter; |
| 1067 | |
| 1068 | ret = 0; |
| 1069 | counters = xt_counters_alloc(num_counters); |
| 1070 | if (!counters) { |
| 1071 | ret = -ENOMEM; |
| 1072 | goto out; |
| 1073 | } |
| 1074 | |
| 1075 | t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), |
| 1076 | "ip6table_%s", name); |
| 1077 | if (!t) { |
| 1078 | ret = -ENOENT; |
| 1079 | goto free_newinfo_counters_untrans; |
| 1080 | } |
| 1081 | |
| 1082 | /* You lied! */ |
| 1083 | if (valid_hooks != t->valid_hooks) { |
| 1084 | ret = -EINVAL; |
| 1085 | goto put_module; |
| 1086 | } |
| 1087 | |
| 1088 | oldinfo = xt_replace_table(t, num_counters, newinfo, &ret); |
| 1089 | if (!oldinfo) |
| 1090 | goto put_module; |
| 1091 | |
| 1092 | /* Update module usage count based on number of rules */ |
| 1093 | if ((oldinfo->number > oldinfo->initial_entries) || |
| 1094 | (newinfo->number <= oldinfo->initial_entries)) |
| 1095 | module_put(t->me); |
| 1096 | if ((oldinfo->number > oldinfo->initial_entries) && |
| 1097 | (newinfo->number <= oldinfo->initial_entries)) |
| 1098 | module_put(t->me); |
| 1099 | |
| 1100 | /* Get the old counters, and synchronize with replace */ |
| 1101 | get_counters(oldinfo, counters); |
| 1102 | |
| 1103 | /* Decrease module usage counts and free resource */ |
| 1104 | xt_entry_foreach(iter, oldinfo->entries, oldinfo->size) |
| 1105 | cleanup_entry(iter, net); |
| 1106 | |
| 1107 | xt_free_table_info(oldinfo); |
| 1108 | if (copy_to_user(counters_ptr, counters, |
| 1109 | sizeof(struct xt_counters) * num_counters) != 0) { |
| 1110 | /* Silent error, can't fail, new table is already in place */ |
| 1111 | net_warn_ratelimited("ip6tables: counters copy to user failed while replacing table\n"); |
| 1112 | } |
| 1113 | vfree(counters); |
| 1114 | xt_table_unlock(t); |
| 1115 | return ret; |
| 1116 | |
| 1117 | put_module: |
| 1118 | module_put(t->me); |
| 1119 | xt_table_unlock(t); |
| 1120 | free_newinfo_counters_untrans: |
| 1121 | vfree(counters); |
| 1122 | out: |
| 1123 | return ret; |
| 1124 | } |
| 1125 | |
| 1126 | static int |
| 1127 | do_replace(struct net *net, const void __user *user, unsigned int len) |
| 1128 | { |
| 1129 | int ret; |
| 1130 | struct ip6t_replace tmp; |
| 1131 | struct xt_table_info *newinfo; |
| 1132 | void *loc_cpu_entry; |
| 1133 | struct ip6t_entry *iter; |
| 1134 | |
| 1135 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| 1136 | return -EFAULT; |
| 1137 | |
| 1138 | /* overflow check */ |
| 1139 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) |
| 1140 | return -ENOMEM; |
| 1141 | if (tmp.num_counters == 0) |
| 1142 | return -EINVAL; |
| 1143 | |
| 1144 | tmp.name[sizeof(tmp.name)-1] = 0; |
| 1145 | |
| 1146 | newinfo = xt_alloc_table_info(tmp.size); |
| 1147 | if (!newinfo) |
| 1148 | return -ENOMEM; |
| 1149 | |
| 1150 | loc_cpu_entry = newinfo->entries; |
| 1151 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
| 1152 | tmp.size) != 0) { |
| 1153 | ret = -EFAULT; |
| 1154 | goto free_newinfo; |
| 1155 | } |
| 1156 | |
| 1157 | ret = translate_table(net, newinfo, loc_cpu_entry, &tmp); |
| 1158 | if (ret != 0) |
| 1159 | goto free_newinfo; |
| 1160 | |
| 1161 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
| 1162 | tmp.num_counters, tmp.counters); |
| 1163 | if (ret) |
| 1164 | goto free_newinfo_untrans; |
| 1165 | return 0; |
| 1166 | |
| 1167 | free_newinfo_untrans: |
| 1168 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
| 1169 | cleanup_entry(iter, net); |
| 1170 | free_newinfo: |
| 1171 | xt_free_table_info(newinfo); |
| 1172 | return ret; |
| 1173 | } |
| 1174 | |
| 1175 | static int |
| 1176 | do_add_counters(struct net *net, const void __user *user, unsigned int len, |
| 1177 | int compat) |
| 1178 | { |
| 1179 | unsigned int i; |
| 1180 | struct xt_counters_info tmp; |
| 1181 | struct xt_counters *paddc; |
| 1182 | struct xt_table *t; |
| 1183 | const struct xt_table_info *private; |
| 1184 | int ret = 0; |
| 1185 | struct ip6t_entry *iter; |
| 1186 | unsigned int addend; |
| 1187 | |
| 1188 | paddc = xt_copy_counters_from_user(user, len, &tmp, compat); |
| 1189 | if (IS_ERR(paddc)) |
| 1190 | return PTR_ERR(paddc); |
| 1191 | t = xt_find_table_lock(net, AF_INET6, tmp.name); |
| 1192 | if (!t) { |
| 1193 | ret = -ENOENT; |
| 1194 | goto free; |
| 1195 | } |
| 1196 | |
| 1197 | local_bh_disable(); |
| 1198 | private = t->private; |
| 1199 | if (private->number != tmp.num_counters) { |
| 1200 | ret = -EINVAL; |
| 1201 | goto unlock_up_free; |
| 1202 | } |
| 1203 | |
| 1204 | i = 0; |
| 1205 | addend = xt_write_recseq_begin(); |
| 1206 | xt_entry_foreach(iter, private->entries, private->size) { |
| 1207 | struct xt_counters *tmp; |
| 1208 | |
| 1209 | tmp = xt_get_this_cpu_counter(&iter->counters); |
| 1210 | ADD_COUNTER(*tmp, paddc[i].bcnt, paddc[i].pcnt); |
| 1211 | ++i; |
| 1212 | } |
| 1213 | xt_write_recseq_end(addend); |
| 1214 | unlock_up_free: |
| 1215 | local_bh_enable(); |
| 1216 | xt_table_unlock(t); |
| 1217 | module_put(t->me); |
| 1218 | free: |
| 1219 | vfree(paddc); |
| 1220 | |
| 1221 | return ret; |
| 1222 | } |
| 1223 | |
| 1224 | #ifdef CONFIG_COMPAT |
| 1225 | struct compat_ip6t_replace { |
| 1226 | char name[XT_TABLE_MAXNAMELEN]; |
| 1227 | u32 valid_hooks; |
| 1228 | u32 num_entries; |
| 1229 | u32 size; |
| 1230 | u32 hook_entry[NF_INET_NUMHOOKS]; |
| 1231 | u32 underflow[NF_INET_NUMHOOKS]; |
| 1232 | u32 num_counters; |
| 1233 | compat_uptr_t counters; /* struct xt_counters * */ |
| 1234 | struct compat_ip6t_entry entries[0]; |
| 1235 | }; |
| 1236 | |
| 1237 | static int |
| 1238 | compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr, |
| 1239 | unsigned int *size, struct xt_counters *counters, |
| 1240 | unsigned int i) |
| 1241 | { |
| 1242 | struct xt_entry_target *t; |
| 1243 | struct compat_ip6t_entry __user *ce; |
| 1244 | u_int16_t target_offset, next_offset; |
| 1245 | compat_uint_t origsize; |
| 1246 | const struct xt_entry_match *ematch; |
| 1247 | int ret = 0; |
| 1248 | |
| 1249 | origsize = *size; |
| 1250 | ce = *dstptr; |
| 1251 | if (copy_to_user(ce, e, sizeof(struct ip6t_entry)) != 0 || |
| 1252 | copy_to_user(&ce->counters, &counters[i], |
| 1253 | sizeof(counters[i])) != 0) |
| 1254 | return -EFAULT; |
| 1255 | |
| 1256 | *dstptr += sizeof(struct compat_ip6t_entry); |
| 1257 | *size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1258 | |
| 1259 | xt_ematch_foreach(ematch, e) { |
| 1260 | ret = xt_compat_match_to_user(ematch, dstptr, size); |
| 1261 | if (ret != 0) |
| 1262 | return ret; |
| 1263 | } |
| 1264 | target_offset = e->target_offset - (origsize - *size); |
| 1265 | t = ip6t_get_target(e); |
| 1266 | ret = xt_compat_target_to_user(t, dstptr, size); |
| 1267 | if (ret) |
| 1268 | return ret; |
| 1269 | next_offset = e->next_offset - (origsize - *size); |
| 1270 | if (put_user(target_offset, &ce->target_offset) != 0 || |
| 1271 | put_user(next_offset, &ce->next_offset) != 0) |
| 1272 | return -EFAULT; |
| 1273 | return 0; |
| 1274 | } |
| 1275 | |
| 1276 | static int |
| 1277 | compat_find_calc_match(struct xt_entry_match *m, |
| 1278 | const struct ip6t_ip6 *ipv6, |
| 1279 | int *size) |
| 1280 | { |
| 1281 | struct xt_match *match; |
| 1282 | |
| 1283 | match = xt_request_find_match(NFPROTO_IPV6, m->u.user.name, |
| 1284 | m->u.user.revision); |
| 1285 | if (IS_ERR(match)) |
| 1286 | return PTR_ERR(match); |
| 1287 | |
| 1288 | m->u.kernel.match = match; |
| 1289 | *size += xt_compat_match_offset(match); |
| 1290 | return 0; |
| 1291 | } |
| 1292 | |
| 1293 | static void compat_release_entry(struct compat_ip6t_entry *e) |
| 1294 | { |
| 1295 | struct xt_entry_target *t; |
| 1296 | struct xt_entry_match *ematch; |
| 1297 | |
| 1298 | /* Cleanup all matches */ |
| 1299 | xt_ematch_foreach(ematch, e) |
| 1300 | module_put(ematch->u.kernel.match->me); |
| 1301 | t = compat_ip6t_get_target(e); |
| 1302 | module_put(t->u.kernel.target->me); |
| 1303 | } |
| 1304 | |
| 1305 | static int |
| 1306 | check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e, |
| 1307 | struct xt_table_info *newinfo, |
| 1308 | unsigned int *size, |
| 1309 | const unsigned char *base, |
| 1310 | const unsigned char *limit) |
| 1311 | { |
| 1312 | struct xt_entry_match *ematch; |
| 1313 | struct xt_entry_target *t; |
| 1314 | struct xt_target *target; |
| 1315 | unsigned int entry_offset; |
| 1316 | unsigned int j; |
| 1317 | int ret, off; |
| 1318 | |
| 1319 | if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 || |
| 1320 | (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit || |
| 1321 | (unsigned char *)e + e->next_offset > limit) |
| 1322 | return -EINVAL; |
| 1323 | |
| 1324 | if (e->next_offset < sizeof(struct compat_ip6t_entry) + |
| 1325 | sizeof(struct compat_xt_entry_target)) |
| 1326 | return -EINVAL; |
| 1327 | |
| 1328 | if (!ip6_checkentry(&e->ipv6)) |
| 1329 | return -EINVAL; |
| 1330 | |
| 1331 | ret = xt_compat_check_entry_offsets(e, e->elems, |
| 1332 | e->target_offset, e->next_offset); |
| 1333 | if (ret) |
| 1334 | return ret; |
| 1335 | |
| 1336 | off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1337 | entry_offset = (void *)e - (void *)base; |
| 1338 | j = 0; |
| 1339 | xt_ematch_foreach(ematch, e) { |
| 1340 | ret = compat_find_calc_match(ematch, &e->ipv6, &off); |
| 1341 | if (ret != 0) |
| 1342 | goto release_matches; |
| 1343 | ++j; |
| 1344 | } |
| 1345 | |
| 1346 | t = compat_ip6t_get_target(e); |
| 1347 | target = xt_request_find_target(NFPROTO_IPV6, t->u.user.name, |
| 1348 | t->u.user.revision); |
| 1349 | if (IS_ERR(target)) { |
| 1350 | ret = PTR_ERR(target); |
| 1351 | goto release_matches; |
| 1352 | } |
| 1353 | t->u.kernel.target = target; |
| 1354 | |
| 1355 | off += xt_compat_target_offset(target); |
| 1356 | *size += off; |
| 1357 | ret = xt_compat_add_offset(AF_INET6, entry_offset, off); |
| 1358 | if (ret) |
| 1359 | goto out; |
| 1360 | |
| 1361 | return 0; |
| 1362 | |
| 1363 | out: |
| 1364 | module_put(t->u.kernel.target->me); |
| 1365 | release_matches: |
| 1366 | xt_ematch_foreach(ematch, e) { |
| 1367 | if (j-- == 0) |
| 1368 | break; |
| 1369 | module_put(ematch->u.kernel.match->me); |
| 1370 | } |
| 1371 | return ret; |
| 1372 | } |
| 1373 | |
| 1374 | static void |
| 1375 | compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr, |
| 1376 | unsigned int *size, |
| 1377 | struct xt_table_info *newinfo, unsigned char *base) |
| 1378 | { |
| 1379 | struct xt_entry_target *t; |
| 1380 | struct ip6t_entry *de; |
| 1381 | unsigned int origsize; |
| 1382 | int h; |
| 1383 | struct xt_entry_match *ematch; |
| 1384 | |
| 1385 | origsize = *size; |
| 1386 | de = *dstptr; |
| 1387 | memcpy(de, e, sizeof(struct ip6t_entry)); |
| 1388 | memcpy(&de->counters, &e->counters, sizeof(e->counters)); |
| 1389 | |
| 1390 | *dstptr += sizeof(struct ip6t_entry); |
| 1391 | *size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1392 | |
| 1393 | xt_ematch_foreach(ematch, e) |
| 1394 | xt_compat_match_from_user(ematch, dstptr, size); |
| 1395 | |
| 1396 | de->target_offset = e->target_offset - (origsize - *size); |
| 1397 | t = compat_ip6t_get_target(e); |
| 1398 | xt_compat_target_from_user(t, dstptr, size); |
| 1399 | |
| 1400 | de->next_offset = e->next_offset - (origsize - *size); |
| 1401 | for (h = 0; h < NF_INET_NUMHOOKS; h++) { |
| 1402 | if ((unsigned char *)de - base < newinfo->hook_entry[h]) |
| 1403 | newinfo->hook_entry[h] -= origsize - *size; |
| 1404 | if ((unsigned char *)de - base < newinfo->underflow[h]) |
| 1405 | newinfo->underflow[h] -= origsize - *size; |
| 1406 | } |
| 1407 | } |
| 1408 | |
| 1409 | static int |
| 1410 | translate_compat_table(struct net *net, |
| 1411 | struct xt_table_info **pinfo, |
| 1412 | void **pentry0, |
| 1413 | const struct compat_ip6t_replace *compatr) |
| 1414 | { |
| 1415 | unsigned int i, j; |
| 1416 | struct xt_table_info *newinfo, *info; |
| 1417 | void *pos, *entry0, *entry1; |
| 1418 | struct compat_ip6t_entry *iter0; |
| 1419 | struct ip6t_replace repl; |
| 1420 | unsigned int size; |
| 1421 | int ret; |
| 1422 | |
| 1423 | info = *pinfo; |
| 1424 | entry0 = *pentry0; |
| 1425 | size = compatr->size; |
| 1426 | info->number = compatr->num_entries; |
| 1427 | |
| 1428 | j = 0; |
| 1429 | xt_compat_lock(AF_INET6); |
| 1430 | ret = xt_compat_init_offsets(AF_INET6, compatr->num_entries); |
| 1431 | if (ret) |
| 1432 | goto out_unlock; |
| 1433 | /* Walk through entries, checking offsets. */ |
| 1434 | xt_entry_foreach(iter0, entry0, compatr->size) { |
| 1435 | ret = check_compat_entry_size_and_hooks(iter0, info, &size, |
| 1436 | entry0, |
| 1437 | entry0 + compatr->size); |
| 1438 | if (ret != 0) |
| 1439 | goto out_unlock; |
| 1440 | ++j; |
| 1441 | } |
| 1442 | |
| 1443 | ret = -EINVAL; |
| 1444 | if (j != compatr->num_entries) |
| 1445 | goto out_unlock; |
| 1446 | |
| 1447 | ret = -ENOMEM; |
| 1448 | newinfo = xt_alloc_table_info(size); |
| 1449 | if (!newinfo) |
| 1450 | goto out_unlock; |
| 1451 | |
| 1452 | newinfo->number = compatr->num_entries; |
| 1453 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1454 | newinfo->hook_entry[i] = compatr->hook_entry[i]; |
| 1455 | newinfo->underflow[i] = compatr->underflow[i]; |
| 1456 | } |
| 1457 | entry1 = newinfo->entries; |
| 1458 | pos = entry1; |
| 1459 | size = compatr->size; |
| 1460 | xt_entry_foreach(iter0, entry0, compatr->size) |
| 1461 | compat_copy_entry_from_user(iter0, &pos, &size, |
| 1462 | newinfo, entry1); |
| 1463 | |
| 1464 | /* all module references in entry0 are now gone. */ |
| 1465 | xt_compat_flush_offsets(AF_INET6); |
| 1466 | xt_compat_unlock(AF_INET6); |
| 1467 | |
| 1468 | memcpy(&repl, compatr, sizeof(*compatr)); |
| 1469 | |
| 1470 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1471 | repl.hook_entry[i] = newinfo->hook_entry[i]; |
| 1472 | repl.underflow[i] = newinfo->underflow[i]; |
| 1473 | } |
| 1474 | |
| 1475 | repl.num_counters = 0; |
| 1476 | repl.counters = NULL; |
| 1477 | repl.size = newinfo->size; |
| 1478 | ret = translate_table(net, newinfo, entry1, &repl); |
| 1479 | if (ret) |
| 1480 | goto free_newinfo; |
| 1481 | |
| 1482 | *pinfo = newinfo; |
| 1483 | *pentry0 = entry1; |
| 1484 | xt_free_table_info(info); |
| 1485 | return 0; |
| 1486 | |
| 1487 | free_newinfo: |
| 1488 | xt_free_table_info(newinfo); |
| 1489 | return ret; |
| 1490 | out_unlock: |
| 1491 | xt_compat_flush_offsets(AF_INET6); |
| 1492 | xt_compat_unlock(AF_INET6); |
| 1493 | xt_entry_foreach(iter0, entry0, compatr->size) { |
| 1494 | if (j-- == 0) |
| 1495 | break; |
| 1496 | compat_release_entry(iter0); |
| 1497 | } |
| 1498 | return ret; |
| 1499 | } |
| 1500 | |
| 1501 | static int |
| 1502 | compat_do_replace(struct net *net, void __user *user, unsigned int len) |
| 1503 | { |
| 1504 | int ret; |
| 1505 | struct compat_ip6t_replace tmp; |
| 1506 | struct xt_table_info *newinfo; |
| 1507 | void *loc_cpu_entry; |
| 1508 | struct ip6t_entry *iter; |
| 1509 | |
| 1510 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| 1511 | return -EFAULT; |
| 1512 | |
| 1513 | /* overflow check */ |
| 1514 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) |
| 1515 | return -ENOMEM; |
| 1516 | if (tmp.num_counters == 0) |
| 1517 | return -EINVAL; |
| 1518 | |
| 1519 | tmp.name[sizeof(tmp.name)-1] = 0; |
| 1520 | |
| 1521 | newinfo = xt_alloc_table_info(tmp.size); |
| 1522 | if (!newinfo) |
| 1523 | return -ENOMEM; |
| 1524 | |
| 1525 | loc_cpu_entry = newinfo->entries; |
| 1526 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
| 1527 | tmp.size) != 0) { |
| 1528 | ret = -EFAULT; |
| 1529 | goto free_newinfo; |
| 1530 | } |
| 1531 | |
| 1532 | ret = translate_compat_table(net, &newinfo, &loc_cpu_entry, &tmp); |
| 1533 | if (ret != 0) |
| 1534 | goto free_newinfo; |
| 1535 | |
| 1536 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
| 1537 | tmp.num_counters, compat_ptr(tmp.counters)); |
| 1538 | if (ret) |
| 1539 | goto free_newinfo_untrans; |
| 1540 | return 0; |
| 1541 | |
| 1542 | free_newinfo_untrans: |
| 1543 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
| 1544 | cleanup_entry(iter, net); |
| 1545 | free_newinfo: |
| 1546 | xt_free_table_info(newinfo); |
| 1547 | return ret; |
| 1548 | } |
| 1549 | |
| 1550 | static int |
| 1551 | compat_do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, |
| 1552 | unsigned int len) |
| 1553 | { |
| 1554 | int ret; |
| 1555 | |
| 1556 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
| 1557 | return -EPERM; |
| 1558 | |
| 1559 | switch (cmd) { |
| 1560 | case IP6T_SO_SET_REPLACE: |
| 1561 | ret = compat_do_replace(sock_net(sk), user, len); |
| 1562 | break; |
| 1563 | |
| 1564 | case IP6T_SO_SET_ADD_COUNTERS: |
| 1565 | ret = do_add_counters(sock_net(sk), user, len, 1); |
| 1566 | break; |
| 1567 | |
| 1568 | default: |
| 1569 | ret = -EINVAL; |
| 1570 | } |
| 1571 | |
| 1572 | return ret; |
| 1573 | } |
| 1574 | |
| 1575 | struct compat_ip6t_get_entries { |
| 1576 | char name[XT_TABLE_MAXNAMELEN]; |
| 1577 | compat_uint_t size; |
| 1578 | struct compat_ip6t_entry entrytable[0]; |
| 1579 | }; |
| 1580 | |
| 1581 | static int |
| 1582 | compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table, |
| 1583 | void __user *userptr) |
| 1584 | { |
| 1585 | struct xt_counters *counters; |
| 1586 | const struct xt_table_info *private = table->private; |
| 1587 | void __user *pos; |
| 1588 | unsigned int size; |
| 1589 | int ret = 0; |
| 1590 | unsigned int i = 0; |
| 1591 | struct ip6t_entry *iter; |
| 1592 | |
| 1593 | counters = alloc_counters(table); |
| 1594 | if (IS_ERR(counters)) |
| 1595 | return PTR_ERR(counters); |
| 1596 | |
| 1597 | pos = userptr; |
| 1598 | size = total_size; |
| 1599 | xt_entry_foreach(iter, private->entries, total_size) { |
| 1600 | ret = compat_copy_entry_to_user(iter, &pos, |
| 1601 | &size, counters, i++); |
| 1602 | if (ret != 0) |
| 1603 | break; |
| 1604 | } |
| 1605 | |
| 1606 | vfree(counters); |
| 1607 | return ret; |
| 1608 | } |
| 1609 | |
| 1610 | static int |
| 1611 | compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr, |
| 1612 | int *len) |
| 1613 | { |
| 1614 | int ret; |
| 1615 | struct compat_ip6t_get_entries get; |
| 1616 | struct xt_table *t; |
| 1617 | |
| 1618 | if (*len < sizeof(get)) |
| 1619 | return -EINVAL; |
| 1620 | |
| 1621 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) |
| 1622 | return -EFAULT; |
| 1623 | |
| 1624 | if (*len != sizeof(struct compat_ip6t_get_entries) + get.size) |
| 1625 | return -EINVAL; |
| 1626 | |
| 1627 | get.name[sizeof(get.name) - 1] = '\0'; |
| 1628 | |
| 1629 | xt_compat_lock(AF_INET6); |
| 1630 | t = xt_find_table_lock(net, AF_INET6, get.name); |
| 1631 | if (t) { |
| 1632 | const struct xt_table_info *private = t->private; |
| 1633 | struct xt_table_info info; |
| 1634 | ret = compat_table_info(private, &info); |
| 1635 | if (!ret && get.size == info.size) |
| 1636 | ret = compat_copy_entries_to_user(private->size, |
| 1637 | t, uptr->entrytable); |
| 1638 | else if (!ret) |
| 1639 | ret = -EAGAIN; |
| 1640 | |
| 1641 | xt_compat_flush_offsets(AF_INET6); |
| 1642 | module_put(t->me); |
| 1643 | xt_table_unlock(t); |
| 1644 | } else |
| 1645 | ret = -ENOENT; |
| 1646 | |
| 1647 | xt_compat_unlock(AF_INET6); |
| 1648 | return ret; |
| 1649 | } |
| 1650 | |
| 1651 | static int do_ip6t_get_ctl(struct sock *, int, void __user *, int *); |
| 1652 | |
| 1653 | static int |
| 1654 | compat_do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| 1655 | { |
| 1656 | int ret; |
| 1657 | |
| 1658 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
| 1659 | return -EPERM; |
| 1660 | |
| 1661 | switch (cmd) { |
| 1662 | case IP6T_SO_GET_INFO: |
| 1663 | ret = get_info(sock_net(sk), user, len, 1); |
| 1664 | break; |
| 1665 | case IP6T_SO_GET_ENTRIES: |
| 1666 | ret = compat_get_entries(sock_net(sk), user, len); |
| 1667 | break; |
| 1668 | default: |
| 1669 | ret = do_ip6t_get_ctl(sk, cmd, user, len); |
| 1670 | } |
| 1671 | return ret; |
| 1672 | } |
| 1673 | #endif |
| 1674 | |
| 1675 | static int |
| 1676 | do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
| 1677 | { |
| 1678 | int ret; |
| 1679 | |
| 1680 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
| 1681 | return -EPERM; |
| 1682 | |
| 1683 | switch (cmd) { |
| 1684 | case IP6T_SO_SET_REPLACE: |
| 1685 | ret = do_replace(sock_net(sk), user, len); |
| 1686 | break; |
| 1687 | |
| 1688 | case IP6T_SO_SET_ADD_COUNTERS: |
| 1689 | ret = do_add_counters(sock_net(sk), user, len, 0); |
| 1690 | break; |
| 1691 | |
| 1692 | default: |
| 1693 | ret = -EINVAL; |
| 1694 | } |
| 1695 | |
| 1696 | return ret; |
| 1697 | } |
| 1698 | |
| 1699 | static int |
| 1700 | do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| 1701 | { |
| 1702 | int ret; |
| 1703 | |
| 1704 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) |
| 1705 | return -EPERM; |
| 1706 | |
| 1707 | switch (cmd) { |
| 1708 | case IP6T_SO_GET_INFO: |
| 1709 | ret = get_info(sock_net(sk), user, len, 0); |
| 1710 | break; |
| 1711 | |
| 1712 | case IP6T_SO_GET_ENTRIES: |
| 1713 | ret = get_entries(sock_net(sk), user, len); |
| 1714 | break; |
| 1715 | |
| 1716 | case IP6T_SO_GET_REVISION_MATCH: |
| 1717 | case IP6T_SO_GET_REVISION_TARGET: { |
| 1718 | struct xt_get_revision rev; |
| 1719 | int target; |
| 1720 | |
| 1721 | if (*len != sizeof(rev)) { |
| 1722 | ret = -EINVAL; |
| 1723 | break; |
| 1724 | } |
| 1725 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { |
| 1726 | ret = -EFAULT; |
| 1727 | break; |
| 1728 | } |
| 1729 | rev.name[sizeof(rev.name)-1] = 0; |
| 1730 | |
| 1731 | if (cmd == IP6T_SO_GET_REVISION_TARGET) |
| 1732 | target = 1; |
| 1733 | else |
| 1734 | target = 0; |
| 1735 | |
| 1736 | try_then_request_module(xt_find_revision(AF_INET6, rev.name, |
| 1737 | rev.revision, |
| 1738 | target, &ret), |
| 1739 | "ip6t_%s", rev.name); |
| 1740 | break; |
| 1741 | } |
| 1742 | |
| 1743 | default: |
| 1744 | ret = -EINVAL; |
| 1745 | } |
| 1746 | |
| 1747 | return ret; |
| 1748 | } |
| 1749 | |
| 1750 | static void __ip6t_unregister_table(struct net *net, struct xt_table *table) |
| 1751 | { |
| 1752 | struct xt_table_info *private; |
| 1753 | void *loc_cpu_entry; |
| 1754 | struct module *table_owner = table->me; |
| 1755 | struct ip6t_entry *iter; |
| 1756 | |
| 1757 | private = xt_unregister_table(table); |
| 1758 | |
| 1759 | /* Decrease module usage counts and free resources */ |
| 1760 | loc_cpu_entry = private->entries; |
| 1761 | xt_entry_foreach(iter, loc_cpu_entry, private->size) |
| 1762 | cleanup_entry(iter, net); |
| 1763 | if (private->number > private->initial_entries) |
| 1764 | module_put(table_owner); |
| 1765 | xt_free_table_info(private); |
| 1766 | } |
| 1767 | |
| 1768 | int ip6t_register_table(struct net *net, const struct xt_table *table, |
| 1769 | const struct ip6t_replace *repl, |
| 1770 | const struct nf_hook_ops *ops, |
| 1771 | struct xt_table **res) |
| 1772 | { |
| 1773 | int ret; |
| 1774 | struct xt_table_info *newinfo; |
| 1775 | struct xt_table_info bootstrap = {0}; |
| 1776 | void *loc_cpu_entry; |
| 1777 | struct xt_table *new_table; |
| 1778 | |
| 1779 | newinfo = xt_alloc_table_info(repl->size); |
| 1780 | if (!newinfo) |
| 1781 | return -ENOMEM; |
| 1782 | |
| 1783 | loc_cpu_entry = newinfo->entries; |
| 1784 | memcpy(loc_cpu_entry, repl->entries, repl->size); |
| 1785 | |
| 1786 | ret = translate_table(net, newinfo, loc_cpu_entry, repl); |
| 1787 | if (ret != 0) |
| 1788 | goto out_free; |
| 1789 | |
| 1790 | new_table = xt_register_table(net, table, &bootstrap, newinfo); |
| 1791 | if (IS_ERR(new_table)) { |
| 1792 | ret = PTR_ERR(new_table); |
| 1793 | goto out_free; |
| 1794 | } |
| 1795 | |
| 1796 | /* set res now, will see skbs right after nf_register_net_hooks */ |
| 1797 | WRITE_ONCE(*res, new_table); |
| 1798 | |
| 1799 | ret = nf_register_net_hooks(net, ops, hweight32(table->valid_hooks)); |
| 1800 | if (ret != 0) { |
| 1801 | __ip6t_unregister_table(net, new_table); |
| 1802 | *res = NULL; |
| 1803 | } |
| 1804 | |
| 1805 | return ret; |
| 1806 | |
| 1807 | out_free: |
| 1808 | xt_free_table_info(newinfo); |
| 1809 | return ret; |
| 1810 | } |
| 1811 | |
| 1812 | void ip6t_unregister_table(struct net *net, struct xt_table *table, |
| 1813 | const struct nf_hook_ops *ops) |
| 1814 | { |
| 1815 | nf_unregister_net_hooks(net, ops, hweight32(table->valid_hooks)); |
| 1816 | __ip6t_unregister_table(net, table); |
| 1817 | } |
| 1818 | |
| 1819 | /* Returns 1 if the type and code is matched by the range, 0 otherwise */ |
| 1820 | static inline bool |
| 1821 | icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, |
| 1822 | u_int8_t type, u_int8_t code, |
| 1823 | bool invert) |
| 1824 | { |
| 1825 | return (type == test_type && code >= min_code && code <= max_code) |
| 1826 | ^ invert; |
| 1827 | } |
| 1828 | |
| 1829 | static bool |
| 1830 | icmp6_match(const struct sk_buff *skb, struct xt_action_param *par) |
| 1831 | { |
| 1832 | const struct icmp6hdr *ic; |
| 1833 | struct icmp6hdr _icmph; |
| 1834 | const struct ip6t_icmp *icmpinfo = par->matchinfo; |
| 1835 | |
| 1836 | /* Must not be a fragment. */ |
| 1837 | if (par->fragoff != 0) |
| 1838 | return false; |
| 1839 | |
| 1840 | ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph); |
| 1841 | if (ic == NULL) { |
| 1842 | /* We've been asked to examine this packet, and we |
| 1843 | * can't. Hence, no choice but to drop. |
| 1844 | */ |
| 1845 | par->hotdrop = true; |
| 1846 | return false; |
| 1847 | } |
| 1848 | |
| 1849 | return icmp6_type_code_match(icmpinfo->type, |
| 1850 | icmpinfo->code[0], |
| 1851 | icmpinfo->code[1], |
| 1852 | ic->icmp6_type, ic->icmp6_code, |
| 1853 | !!(icmpinfo->invflags&IP6T_ICMP_INV)); |
| 1854 | } |
| 1855 | |
| 1856 | /* Called when user tries to insert an entry of this type. */ |
| 1857 | static int icmp6_checkentry(const struct xt_mtchk_param *par) |
| 1858 | { |
| 1859 | const struct ip6t_icmp *icmpinfo = par->matchinfo; |
| 1860 | |
| 1861 | /* Must specify no unknown invflags */ |
| 1862 | return (icmpinfo->invflags & ~IP6T_ICMP_INV) ? -EINVAL : 0; |
| 1863 | } |
| 1864 | |
| 1865 | /* The built-in targets: standard (NULL) and error. */ |
| 1866 | static struct xt_target ip6t_builtin_tg[] __read_mostly = { |
| 1867 | { |
| 1868 | .name = XT_STANDARD_TARGET, |
| 1869 | .targetsize = sizeof(int), |
| 1870 | .family = NFPROTO_IPV6, |
| 1871 | #ifdef CONFIG_COMPAT |
| 1872 | .compatsize = sizeof(compat_int_t), |
| 1873 | .compat_from_user = compat_standard_from_user, |
| 1874 | .compat_to_user = compat_standard_to_user, |
| 1875 | #endif |
| 1876 | }, |
| 1877 | { |
| 1878 | .name = XT_ERROR_TARGET, |
| 1879 | .target = ip6t_error, |
| 1880 | .targetsize = XT_FUNCTION_MAXNAMELEN, |
| 1881 | .family = NFPROTO_IPV6, |
| 1882 | }, |
| 1883 | }; |
| 1884 | |
| 1885 | static struct nf_sockopt_ops ip6t_sockopts = { |
| 1886 | .pf = PF_INET6, |
| 1887 | .set_optmin = IP6T_BASE_CTL, |
| 1888 | .set_optmax = IP6T_SO_SET_MAX+1, |
| 1889 | .set = do_ip6t_set_ctl, |
| 1890 | #ifdef CONFIG_COMPAT |
| 1891 | .compat_set = compat_do_ip6t_set_ctl, |
| 1892 | #endif |
| 1893 | .get_optmin = IP6T_BASE_CTL, |
| 1894 | .get_optmax = IP6T_SO_GET_MAX+1, |
| 1895 | .get = do_ip6t_get_ctl, |
| 1896 | #ifdef CONFIG_COMPAT |
| 1897 | .compat_get = compat_do_ip6t_get_ctl, |
| 1898 | #endif |
| 1899 | .owner = THIS_MODULE, |
| 1900 | }; |
| 1901 | |
| 1902 | static struct xt_match ip6t_builtin_mt[] __read_mostly = { |
| 1903 | { |
| 1904 | .name = "icmp6", |
| 1905 | .match = icmp6_match, |
| 1906 | .matchsize = sizeof(struct ip6t_icmp), |
| 1907 | .checkentry = icmp6_checkentry, |
| 1908 | .proto = IPPROTO_ICMPV6, |
| 1909 | .family = NFPROTO_IPV6, |
| 1910 | .me = THIS_MODULE, |
| 1911 | }, |
| 1912 | }; |
| 1913 | |
| 1914 | static int __net_init ip6_tables_net_init(struct net *net) |
| 1915 | { |
| 1916 | return xt_proto_init(net, NFPROTO_IPV6); |
| 1917 | } |
| 1918 | |
| 1919 | static void __net_exit ip6_tables_net_exit(struct net *net) |
| 1920 | { |
| 1921 | xt_proto_fini(net, NFPROTO_IPV6); |
| 1922 | } |
| 1923 | |
| 1924 | static struct pernet_operations ip6_tables_net_ops = { |
| 1925 | .init = ip6_tables_net_init, |
| 1926 | .exit = ip6_tables_net_exit, |
| 1927 | }; |
| 1928 | |
| 1929 | static int __init ip6_tables_init(void) |
| 1930 | { |
| 1931 | int ret; |
| 1932 | |
| 1933 | ret = register_pernet_subsys(&ip6_tables_net_ops); |
| 1934 | if (ret < 0) |
| 1935 | goto err1; |
| 1936 | |
| 1937 | /* No one else will be downing sem now, so we won't sleep */ |
| 1938 | ret = xt_register_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg)); |
| 1939 | if (ret < 0) |
| 1940 | goto err2; |
| 1941 | ret = xt_register_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt)); |
| 1942 | if (ret < 0) |
| 1943 | goto err4; |
| 1944 | |
| 1945 | /* Register setsockopt */ |
| 1946 | ret = nf_register_sockopt(&ip6t_sockopts); |
| 1947 | if (ret < 0) |
| 1948 | goto err5; |
| 1949 | |
| 1950 | pr_info("(C) 2000-2006 Netfilter Core Team\n"); |
| 1951 | return 0; |
| 1952 | |
| 1953 | err5: |
| 1954 | xt_unregister_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt)); |
| 1955 | err4: |
| 1956 | xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg)); |
| 1957 | err2: |
| 1958 | unregister_pernet_subsys(&ip6_tables_net_ops); |
| 1959 | err1: |
| 1960 | return ret; |
| 1961 | } |
| 1962 | |
| 1963 | static void __exit ip6_tables_fini(void) |
| 1964 | { |
| 1965 | nf_unregister_sockopt(&ip6t_sockopts); |
| 1966 | |
| 1967 | xt_unregister_matches(ip6t_builtin_mt, ARRAY_SIZE(ip6t_builtin_mt)); |
| 1968 | xt_unregister_targets(ip6t_builtin_tg, ARRAY_SIZE(ip6t_builtin_tg)); |
| 1969 | unregister_pernet_subsys(&ip6_tables_net_ops); |
| 1970 | } |
| 1971 | |
| 1972 | EXPORT_SYMBOL(ip6t_register_table); |
| 1973 | EXPORT_SYMBOL(ip6t_unregister_table); |
| 1974 | EXPORT_SYMBOL(ip6t_do_table); |
| 1975 | |
| 1976 | module_init(ip6_tables_init); |
| 1977 | module_exit(ip6_tables_fini); |