| 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 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 12 | #include <linux/capability.h> |
| 13 | #include <linux/in.h> |
| 14 | #include <linux/skbuff.h> |
| 15 | #include <linux/kmod.h> |
| 16 | #include <linux/vmalloc.h> |
| 17 | #include <linux/netdevice.h> |
| 18 | #include <linux/module.h> |
| 19 | #include <linux/poison.h> |
| 20 | #include <linux/icmpv6.h> |
| 21 | #include <net/ipv6.h> |
| 22 | #include <net/compat.h> |
| 23 | #include <asm/uaccess.h> |
| 24 | #include <linux/mutex.h> |
| 25 | #include <linux/proc_fs.h> |
| 26 | #include <linux/err.h> |
| 27 | #include <linux/cpumask.h> |
| 28 | |
| 29 | #include <linux/netfilter_ipv6/ip6_tables.h> |
| 30 | #include <linux/netfilter/x_tables.h> |
| 31 | #include <net/netfilter/nf_log.h> |
| 32 | #include "../../netfilter/xt_repldata.h" |
| 33 | |
| 34 | MODULE_LICENSE("GPL"); |
| 35 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); |
| 36 | MODULE_DESCRIPTION("IPv6 packet filter"); |
| 37 | |
| 38 | /*#define DEBUG_IP_FIREWALL*/ |
| 39 | /*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */ |
| 40 | /*#define DEBUG_IP_FIREWALL_USER*/ |
| 41 | |
| 42 | #ifdef DEBUG_IP_FIREWALL |
| 43 | #define dprintf(format, args...) printk(format , ## args) |
| 44 | #else |
| 45 | #define dprintf(format, args...) |
| 46 | #endif |
| 47 | |
| 48 | #ifdef DEBUG_IP_FIREWALL_USER |
| 49 | #define duprintf(format, args...) printk(format , ## args) |
| 50 | #else |
| 51 | #define duprintf(format, args...) |
| 52 | #endif |
| 53 | |
| 54 | #ifdef CONFIG_NETFILTER_DEBUG |
| 55 | #define IP_NF_ASSERT(x) \ |
| 56 | do { \ |
| 57 | if (!(x)) \ |
| 58 | printk("IP_NF_ASSERT: %s:%s:%u\n", \ |
| 59 | __func__, __FILE__, __LINE__); \ |
| 60 | } while(0) |
| 61 | #else |
| 62 | #define IP_NF_ASSERT(x) |
| 63 | #endif |
| 64 | |
| 65 | #if 0 |
| 66 | /* All the better to debug you with... */ |
| 67 | #define static |
| 68 | #define inline |
| 69 | #endif |
| 70 | |
| 71 | void *ip6t_alloc_initial_table(const struct xt_table *info) |
| 72 | { |
| 73 | return xt_alloc_initial_table(ip6t, IP6T); |
| 74 | } |
| 75 | EXPORT_SYMBOL_GPL(ip6t_alloc_initial_table); |
| 76 | |
| 77 | /* |
| 78 | We keep a set of rules for each CPU, so we can avoid write-locking |
| 79 | them in the softirq when updating the counters and therefore |
| 80 | only need to read-lock in the softirq; doing a write_lock_bh() in user |
| 81 | context stops packets coming through and allows user context to read |
| 82 | the counters or update the rules. |
| 83 | |
| 84 | Hence the start of any table is given by get_table() below. */ |
| 85 | |
| 86 | /* Check for an extension */ |
| 87 | int |
| 88 | ip6t_ext_hdr(u8 nexthdr) |
| 89 | { |
| 90 | return ( (nexthdr == IPPROTO_HOPOPTS) || |
| 91 | (nexthdr == IPPROTO_ROUTING) || |
| 92 | (nexthdr == IPPROTO_FRAGMENT) || |
| 93 | (nexthdr == IPPROTO_ESP) || |
| 94 | (nexthdr == IPPROTO_AH) || |
| 95 | (nexthdr == IPPROTO_NONE) || |
| 96 | (nexthdr == IPPROTO_DSTOPTS) ); |
| 97 | } |
| 98 | |
| 99 | /* Returns whether matches rule or not. */ |
| 100 | /* Performance critical - called for every packet */ |
| 101 | static inline bool |
| 102 | ip6_packet_match(const struct sk_buff *skb, |
| 103 | const char *indev, |
| 104 | const char *outdev, |
| 105 | const struct ip6t_ip6 *ip6info, |
| 106 | unsigned int *protoff, |
| 107 | int *fragoff, bool *hotdrop) |
| 108 | { |
| 109 | unsigned long ret; |
| 110 | const struct ipv6hdr *ipv6 = ipv6_hdr(skb); |
| 111 | |
| 112 | #define FWINV(bool, invflg) ((bool) ^ !!(ip6info->invflags & (invflg))) |
| 113 | |
| 114 | if (FWINV(ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk, |
| 115 | &ip6info->src), IP6T_INV_SRCIP) || |
| 116 | FWINV(ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk, |
| 117 | &ip6info->dst), IP6T_INV_DSTIP)) { |
| 118 | dprintf("Source or dest mismatch.\n"); |
| 119 | /* |
| 120 | dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr, |
| 121 | ipinfo->smsk.s_addr, ipinfo->src.s_addr, |
| 122 | ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : ""); |
| 123 | dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr, |
| 124 | ipinfo->dmsk.s_addr, ipinfo->dst.s_addr, |
| 125 | ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/ |
| 126 | return false; |
| 127 | } |
| 128 | |
| 129 | ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask); |
| 130 | |
| 131 | if (FWINV(ret != 0, IP6T_INV_VIA_IN)) { |
| 132 | dprintf("VIA in mismatch (%s vs %s).%s\n", |
| 133 | indev, ip6info->iniface, |
| 134 | ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":""); |
| 135 | return false; |
| 136 | } |
| 137 | |
| 138 | ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask); |
| 139 | |
| 140 | if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) { |
| 141 | dprintf("VIA out mismatch (%s vs %s).%s\n", |
| 142 | outdev, ip6info->outiface, |
| 143 | ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":""); |
| 144 | return false; |
| 145 | } |
| 146 | |
| 147 | /* ... might want to do something with class and flowlabel here ... */ |
| 148 | |
| 149 | /* look for the desired protocol header */ |
| 150 | if((ip6info->flags & IP6T_F_PROTO)) { |
| 151 | int protohdr; |
| 152 | unsigned short _frag_off; |
| 153 | |
| 154 | protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off); |
| 155 | if (protohdr < 0) { |
| 156 | if (_frag_off == 0) |
| 157 | *hotdrop = true; |
| 158 | return false; |
| 159 | } |
| 160 | *fragoff = _frag_off; |
| 161 | |
| 162 | dprintf("Packet protocol %hi ?= %s%hi.\n", |
| 163 | protohdr, |
| 164 | ip6info->invflags & IP6T_INV_PROTO ? "!":"", |
| 165 | ip6info->proto); |
| 166 | |
| 167 | if (ip6info->proto == protohdr) { |
| 168 | if(ip6info->invflags & IP6T_INV_PROTO) { |
| 169 | return false; |
| 170 | } |
| 171 | return true; |
| 172 | } |
| 173 | |
| 174 | /* We need match for the '-p all', too! */ |
| 175 | if ((ip6info->proto != 0) && |
| 176 | !(ip6info->invflags & IP6T_INV_PROTO)) |
| 177 | return false; |
| 178 | } |
| 179 | return true; |
| 180 | } |
| 181 | |
| 182 | /* should be ip6 safe */ |
| 183 | static bool |
| 184 | ip6_checkentry(const struct ip6t_ip6 *ipv6) |
| 185 | { |
| 186 | if (ipv6->flags & ~IP6T_F_MASK) { |
| 187 | duprintf("Unknown flag bits set: %08X\n", |
| 188 | ipv6->flags & ~IP6T_F_MASK); |
| 189 | return false; |
| 190 | } |
| 191 | if (ipv6->invflags & ~IP6T_INV_MASK) { |
| 192 | duprintf("Unknown invflag bits set: %08X\n", |
| 193 | ipv6->invflags & ~IP6T_INV_MASK); |
| 194 | return false; |
| 195 | } |
| 196 | return true; |
| 197 | } |
| 198 | |
| 199 | static unsigned int |
| 200 | ip6t_error(struct sk_buff *skb, const struct xt_target_param *par) |
| 201 | { |
| 202 | if (net_ratelimit()) |
| 203 | printk("ip6_tables: error: `%s'\n", |
| 204 | (const char *)par->targinfo); |
| 205 | |
| 206 | return NF_DROP; |
| 207 | } |
| 208 | |
| 209 | /* Performance critical - called for every packet */ |
| 210 | static inline bool |
| 211 | do_match(const struct ip6t_entry_match *m, const struct sk_buff *skb, |
| 212 | struct xt_match_param *par) |
| 213 | { |
| 214 | par->match = m->u.kernel.match; |
| 215 | par->matchinfo = m->data; |
| 216 | |
| 217 | /* Stop iteration if it doesn't match */ |
| 218 | if (!m->u.kernel.match->match(skb, par)) |
| 219 | return true; |
| 220 | else |
| 221 | return false; |
| 222 | } |
| 223 | |
| 224 | static inline struct ip6t_entry * |
| 225 | get_entry(const void *base, unsigned int offset) |
| 226 | { |
| 227 | return (struct ip6t_entry *)(base + offset); |
| 228 | } |
| 229 | |
| 230 | /* All zeroes == unconditional rule. */ |
| 231 | /* Mildly perf critical (only if packet tracing is on) */ |
| 232 | static inline bool unconditional(const struct ip6t_ip6 *ipv6) |
| 233 | { |
| 234 | static const struct ip6t_ip6 uncond; |
| 235 | |
| 236 | return memcmp(ipv6, &uncond, sizeof(uncond)) == 0; |
| 237 | } |
| 238 | |
| 239 | static inline const struct ip6t_entry_target * |
| 240 | ip6t_get_target_c(const struct ip6t_entry *e) |
| 241 | { |
| 242 | return ip6t_get_target((struct ip6t_entry *)e); |
| 243 | } |
| 244 | |
| 245 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
| 246 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) |
| 247 | /* This cries for unification! */ |
| 248 | static const char *const hooknames[] = { |
| 249 | [NF_INET_PRE_ROUTING] = "PREROUTING", |
| 250 | [NF_INET_LOCAL_IN] = "INPUT", |
| 251 | [NF_INET_FORWARD] = "FORWARD", |
| 252 | [NF_INET_LOCAL_OUT] = "OUTPUT", |
| 253 | [NF_INET_POST_ROUTING] = "POSTROUTING", |
| 254 | }; |
| 255 | |
| 256 | enum nf_ip_trace_comments { |
| 257 | NF_IP6_TRACE_COMMENT_RULE, |
| 258 | NF_IP6_TRACE_COMMENT_RETURN, |
| 259 | NF_IP6_TRACE_COMMENT_POLICY, |
| 260 | }; |
| 261 | |
| 262 | static const char *const comments[] = { |
| 263 | [NF_IP6_TRACE_COMMENT_RULE] = "rule", |
| 264 | [NF_IP6_TRACE_COMMENT_RETURN] = "return", |
| 265 | [NF_IP6_TRACE_COMMENT_POLICY] = "policy", |
| 266 | }; |
| 267 | |
| 268 | static struct nf_loginfo trace_loginfo = { |
| 269 | .type = NF_LOG_TYPE_LOG, |
| 270 | .u = { |
| 271 | .log = { |
| 272 | .level = 4, |
| 273 | .logflags = NF_LOG_MASK, |
| 274 | }, |
| 275 | }, |
| 276 | }; |
| 277 | |
| 278 | /* Mildly perf critical (only if packet tracing is on) */ |
| 279 | static inline int |
| 280 | get_chainname_rulenum(const struct ip6t_entry *s, const struct ip6t_entry *e, |
| 281 | const char *hookname, const char **chainname, |
| 282 | const char **comment, unsigned int *rulenum) |
| 283 | { |
| 284 | const struct ip6t_standard_target *t = (void *)ip6t_get_target_c(s); |
| 285 | |
| 286 | if (strcmp(t->target.u.kernel.target->name, IP6T_ERROR_TARGET) == 0) { |
| 287 | /* Head of user chain: ERROR target with chainname */ |
| 288 | *chainname = t->target.data; |
| 289 | (*rulenum) = 0; |
| 290 | } else if (s == e) { |
| 291 | (*rulenum)++; |
| 292 | |
| 293 | if (s->target_offset == sizeof(struct ip6t_entry) && |
| 294 | strcmp(t->target.u.kernel.target->name, |
| 295 | IP6T_STANDARD_TARGET) == 0 && |
| 296 | t->verdict < 0 && |
| 297 | unconditional(&s->ipv6)) { |
| 298 | /* Tail of chains: STANDARD target (return/policy) */ |
| 299 | *comment = *chainname == hookname |
| 300 | ? comments[NF_IP6_TRACE_COMMENT_POLICY] |
| 301 | : comments[NF_IP6_TRACE_COMMENT_RETURN]; |
| 302 | } |
| 303 | return 1; |
| 304 | } else |
| 305 | (*rulenum)++; |
| 306 | |
| 307 | return 0; |
| 308 | } |
| 309 | |
| 310 | static void trace_packet(const struct sk_buff *skb, |
| 311 | unsigned int hook, |
| 312 | const struct net_device *in, |
| 313 | const struct net_device *out, |
| 314 | const char *tablename, |
| 315 | const struct xt_table_info *private, |
| 316 | const struct ip6t_entry *e) |
| 317 | { |
| 318 | const void *table_base; |
| 319 | const struct ip6t_entry *root; |
| 320 | const char *hookname, *chainname, *comment; |
| 321 | const struct ip6t_entry *iter; |
| 322 | unsigned int rulenum = 0; |
| 323 | |
| 324 | table_base = private->entries[smp_processor_id()]; |
| 325 | root = get_entry(table_base, private->hook_entry[hook]); |
| 326 | |
| 327 | hookname = chainname = hooknames[hook]; |
| 328 | comment = comments[NF_IP6_TRACE_COMMENT_RULE]; |
| 329 | |
| 330 | xt_entry_foreach(iter, root, private->size - private->hook_entry[hook]) |
| 331 | if (get_chainname_rulenum(iter, e, hookname, |
| 332 | &chainname, &comment, &rulenum) != 0) |
| 333 | break; |
| 334 | |
| 335 | nf_log_packet(AF_INET6, hook, skb, in, out, &trace_loginfo, |
| 336 | "TRACE: %s:%s:%s:%u ", |
| 337 | tablename, chainname, comment, rulenum); |
| 338 | } |
| 339 | #endif |
| 340 | |
| 341 | static inline __pure struct ip6t_entry * |
| 342 | ip6t_next_entry(const struct ip6t_entry *entry) |
| 343 | { |
| 344 | return (void *)entry + entry->next_offset; |
| 345 | } |
| 346 | |
| 347 | /* Returns one of the generic firewall policies, like NF_ACCEPT. */ |
| 348 | unsigned int |
| 349 | ip6t_do_table(struct sk_buff *skb, |
| 350 | unsigned int hook, |
| 351 | const struct net_device *in, |
| 352 | const struct net_device *out, |
| 353 | struct xt_table *table) |
| 354 | { |
| 355 | #define tb_comefrom ((struct ip6t_entry *)table_base)->comefrom |
| 356 | |
| 357 | static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
| 358 | bool hotdrop = false; |
| 359 | /* Initializing verdict to NF_DROP keeps gcc happy. */ |
| 360 | unsigned int verdict = NF_DROP; |
| 361 | const char *indev, *outdev; |
| 362 | const void *table_base; |
| 363 | struct ip6t_entry *e, *back; |
| 364 | const struct xt_table_info *private; |
| 365 | struct xt_match_param mtpar; |
| 366 | struct xt_target_param tgpar; |
| 367 | |
| 368 | /* Initialization */ |
| 369 | indev = in ? in->name : nulldevname; |
| 370 | outdev = out ? out->name : nulldevname; |
| 371 | /* We handle fragments by dealing with the first fragment as |
| 372 | * if it was a normal packet. All other fragments are treated |
| 373 | * normally, except that they will NEVER match rules that ask |
| 374 | * things we don't know, ie. tcp syn flag or ports). If the |
| 375 | * rule is also a fragment-specific rule, non-fragments won't |
| 376 | * match it. */ |
| 377 | mtpar.hotdrop = &hotdrop; |
| 378 | mtpar.in = tgpar.in = in; |
| 379 | mtpar.out = tgpar.out = out; |
| 380 | mtpar.family = tgpar.family = NFPROTO_IPV6; |
| 381 | mtpar.hooknum = tgpar.hooknum = hook; |
| 382 | |
| 383 | IP_NF_ASSERT(table->valid_hooks & (1 << hook)); |
| 384 | |
| 385 | xt_info_rdlock_bh(); |
| 386 | private = table->private; |
| 387 | table_base = private->entries[smp_processor_id()]; |
| 388 | |
| 389 | e = get_entry(table_base, private->hook_entry[hook]); |
| 390 | |
| 391 | /* For return from builtin chain */ |
| 392 | back = get_entry(table_base, private->underflow[hook]); |
| 393 | |
| 394 | do { |
| 395 | const struct ip6t_entry_target *t; |
| 396 | const struct xt_entry_match *ematch; |
| 397 | |
| 398 | IP_NF_ASSERT(e); |
| 399 | IP_NF_ASSERT(back); |
| 400 | if (!ip6_packet_match(skb, indev, outdev, &e->ipv6, |
| 401 | &mtpar.thoff, &mtpar.fragoff, &hotdrop)) { |
| 402 | no_match: |
| 403 | e = ip6t_next_entry(e); |
| 404 | continue; |
| 405 | } |
| 406 | |
| 407 | xt_ematch_foreach(ematch, e) |
| 408 | if (do_match(ematch, skb, &mtpar) != 0) |
| 409 | goto no_match; |
| 410 | |
| 411 | ADD_COUNTER(e->counters, |
| 412 | ntohs(ipv6_hdr(skb)->payload_len) + |
| 413 | sizeof(struct ipv6hdr), 1); |
| 414 | |
| 415 | t = ip6t_get_target_c(e); |
| 416 | IP_NF_ASSERT(t->u.kernel.target); |
| 417 | |
| 418 | #if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \ |
| 419 | defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE) |
| 420 | /* The packet is traced: log it */ |
| 421 | if (unlikely(skb->nf_trace)) |
| 422 | trace_packet(skb, hook, in, out, |
| 423 | table->name, private, e); |
| 424 | #endif |
| 425 | /* Standard target? */ |
| 426 | if (!t->u.kernel.target->target) { |
| 427 | int v; |
| 428 | |
| 429 | v = ((struct ip6t_standard_target *)t)->verdict; |
| 430 | if (v < 0) { |
| 431 | /* Pop from stack? */ |
| 432 | if (v != IP6T_RETURN) { |
| 433 | verdict = (unsigned)(-v) - 1; |
| 434 | break; |
| 435 | } |
| 436 | e = back; |
| 437 | back = get_entry(table_base, back->comefrom); |
| 438 | continue; |
| 439 | } |
| 440 | if (table_base + v != ip6t_next_entry(e) && |
| 441 | !(e->ipv6.flags & IP6T_F_GOTO)) { |
| 442 | /* Save old back ptr in next entry */ |
| 443 | struct ip6t_entry *next = ip6t_next_entry(e); |
| 444 | next->comefrom = (void *)back - table_base; |
| 445 | /* set back pointer to next entry */ |
| 446 | back = next; |
| 447 | } |
| 448 | |
| 449 | e = get_entry(table_base, v); |
| 450 | continue; |
| 451 | } |
| 452 | |
| 453 | /* Targets which reenter must return |
| 454 | abs. verdicts */ |
| 455 | tgpar.target = t->u.kernel.target; |
| 456 | tgpar.targinfo = t->data; |
| 457 | |
| 458 | #ifdef CONFIG_NETFILTER_DEBUG |
| 459 | tb_comefrom = 0xeeeeeeec; |
| 460 | #endif |
| 461 | verdict = t->u.kernel.target->target(skb, &tgpar); |
| 462 | |
| 463 | #ifdef CONFIG_NETFILTER_DEBUG |
| 464 | if (tb_comefrom != 0xeeeeeeec && verdict == IP6T_CONTINUE) { |
| 465 | printk("Target %s reentered!\n", |
| 466 | t->u.kernel.target->name); |
| 467 | verdict = NF_DROP; |
| 468 | } |
| 469 | tb_comefrom = 0x57acc001; |
| 470 | #endif |
| 471 | if (verdict == IP6T_CONTINUE) |
| 472 | e = ip6t_next_entry(e); |
| 473 | else |
| 474 | /* Verdict */ |
| 475 | break; |
| 476 | } while (!hotdrop); |
| 477 | |
| 478 | #ifdef CONFIG_NETFILTER_DEBUG |
| 479 | tb_comefrom = NETFILTER_LINK_POISON; |
| 480 | #endif |
| 481 | xt_info_rdunlock_bh(); |
| 482 | |
| 483 | #ifdef DEBUG_ALLOW_ALL |
| 484 | return NF_ACCEPT; |
| 485 | #else |
| 486 | if (hotdrop) |
| 487 | return NF_DROP; |
| 488 | else return verdict; |
| 489 | #endif |
| 490 | |
| 491 | #undef tb_comefrom |
| 492 | } |
| 493 | |
| 494 | /* Figures out from what hook each rule can be called: returns 0 if |
| 495 | there are loops. Puts hook bitmask in comefrom. */ |
| 496 | static int |
| 497 | mark_source_chains(const struct xt_table_info *newinfo, |
| 498 | unsigned int valid_hooks, void *entry0) |
| 499 | { |
| 500 | unsigned int hook; |
| 501 | |
| 502 | /* No recursion; use packet counter to save back ptrs (reset |
| 503 | to 0 as we leave), and comefrom to save source hook bitmask */ |
| 504 | for (hook = 0; hook < NF_INET_NUMHOOKS; hook++) { |
| 505 | unsigned int pos = newinfo->hook_entry[hook]; |
| 506 | struct ip6t_entry *e = (struct ip6t_entry *)(entry0 + pos); |
| 507 | |
| 508 | if (!(valid_hooks & (1 << hook))) |
| 509 | continue; |
| 510 | |
| 511 | /* Set initial back pointer. */ |
| 512 | e->counters.pcnt = pos; |
| 513 | |
| 514 | for (;;) { |
| 515 | const struct ip6t_standard_target *t |
| 516 | = (void *)ip6t_get_target_c(e); |
| 517 | int visited = e->comefrom & (1 << hook); |
| 518 | |
| 519 | if (e->comefrom & (1 << NF_INET_NUMHOOKS)) { |
| 520 | printk("iptables: loop hook %u pos %u %08X.\n", |
| 521 | hook, pos, e->comefrom); |
| 522 | return 0; |
| 523 | } |
| 524 | e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS)); |
| 525 | |
| 526 | /* Unconditional return/END. */ |
| 527 | if ((e->target_offset == sizeof(struct ip6t_entry) && |
| 528 | (strcmp(t->target.u.user.name, |
| 529 | IP6T_STANDARD_TARGET) == 0) && |
| 530 | t->verdict < 0 && |
| 531 | unconditional(&e->ipv6)) || visited) { |
| 532 | unsigned int oldpos, size; |
| 533 | |
| 534 | if ((strcmp(t->target.u.user.name, |
| 535 | IP6T_STANDARD_TARGET) == 0) && |
| 536 | t->verdict < -NF_MAX_VERDICT - 1) { |
| 537 | duprintf("mark_source_chains: bad " |
| 538 | "negative verdict (%i)\n", |
| 539 | t->verdict); |
| 540 | return 0; |
| 541 | } |
| 542 | |
| 543 | /* Return: backtrack through the last |
| 544 | big jump. */ |
| 545 | do { |
| 546 | e->comefrom ^= (1<<NF_INET_NUMHOOKS); |
| 547 | #ifdef DEBUG_IP_FIREWALL_USER |
| 548 | if (e->comefrom |
| 549 | & (1 << NF_INET_NUMHOOKS)) { |
| 550 | duprintf("Back unset " |
| 551 | "on hook %u " |
| 552 | "rule %u\n", |
| 553 | hook, pos); |
| 554 | } |
| 555 | #endif |
| 556 | oldpos = pos; |
| 557 | pos = e->counters.pcnt; |
| 558 | e->counters.pcnt = 0; |
| 559 | |
| 560 | /* We're at the start. */ |
| 561 | if (pos == oldpos) |
| 562 | goto next; |
| 563 | |
| 564 | e = (struct ip6t_entry *) |
| 565 | (entry0 + pos); |
| 566 | } while (oldpos == pos + e->next_offset); |
| 567 | |
| 568 | /* Move along one */ |
| 569 | size = e->next_offset; |
| 570 | e = (struct ip6t_entry *) |
| 571 | (entry0 + pos + size); |
| 572 | e->counters.pcnt = pos; |
| 573 | pos += size; |
| 574 | } else { |
| 575 | int newpos = t->verdict; |
| 576 | |
| 577 | if (strcmp(t->target.u.user.name, |
| 578 | IP6T_STANDARD_TARGET) == 0 && |
| 579 | newpos >= 0) { |
| 580 | if (newpos > newinfo->size - |
| 581 | sizeof(struct ip6t_entry)) { |
| 582 | duprintf("mark_source_chains: " |
| 583 | "bad verdict (%i)\n", |
| 584 | newpos); |
| 585 | return 0; |
| 586 | } |
| 587 | /* This a jump; chase it. */ |
| 588 | duprintf("Jump rule %u -> %u\n", |
| 589 | pos, newpos); |
| 590 | } else { |
| 591 | /* ... this is a fallthru */ |
| 592 | newpos = pos + e->next_offset; |
| 593 | } |
| 594 | e = (struct ip6t_entry *) |
| 595 | (entry0 + newpos); |
| 596 | e->counters.pcnt = pos; |
| 597 | pos = newpos; |
| 598 | } |
| 599 | } |
| 600 | next: |
| 601 | duprintf("Finished chain %u\n", hook); |
| 602 | } |
| 603 | return 1; |
| 604 | } |
| 605 | |
| 606 | static void cleanup_match(struct ip6t_entry_match *m, struct net *net) |
| 607 | { |
| 608 | struct xt_mtdtor_param par; |
| 609 | |
| 610 | par.net = net; |
| 611 | par.match = m->u.kernel.match; |
| 612 | par.matchinfo = m->data; |
| 613 | par.family = NFPROTO_IPV6; |
| 614 | if (par.match->destroy != NULL) |
| 615 | par.match->destroy(&par); |
| 616 | module_put(par.match->me); |
| 617 | } |
| 618 | |
| 619 | static int |
| 620 | check_entry(const struct ip6t_entry *e, const char *name) |
| 621 | { |
| 622 | const struct ip6t_entry_target *t; |
| 623 | |
| 624 | if (!ip6_checkentry(&e->ipv6)) { |
| 625 | duprintf("ip_tables: ip check failed %p %s.\n", e, name); |
| 626 | return -EINVAL; |
| 627 | } |
| 628 | |
| 629 | if (e->target_offset + sizeof(struct ip6t_entry_target) > |
| 630 | e->next_offset) |
| 631 | return -EINVAL; |
| 632 | |
| 633 | t = ip6t_get_target_c(e); |
| 634 | if (e->target_offset + t->u.target_size > e->next_offset) |
| 635 | return -EINVAL; |
| 636 | |
| 637 | return 0; |
| 638 | } |
| 639 | |
| 640 | static int check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par) |
| 641 | { |
| 642 | const struct ip6t_ip6 *ipv6 = par->entryinfo; |
| 643 | int ret; |
| 644 | |
| 645 | par->match = m->u.kernel.match; |
| 646 | par->matchinfo = m->data; |
| 647 | |
| 648 | ret = xt_check_match(par, m->u.match_size - sizeof(*m), |
| 649 | ipv6->proto, ipv6->invflags & IP6T_INV_PROTO); |
| 650 | if (ret < 0) { |
| 651 | duprintf("ip_tables: check failed for `%s'.\n", |
| 652 | par.match->name); |
| 653 | return ret; |
| 654 | } |
| 655 | return 0; |
| 656 | } |
| 657 | |
| 658 | static int |
| 659 | find_check_match(struct ip6t_entry_match *m, struct xt_mtchk_param *par) |
| 660 | { |
| 661 | struct xt_match *match; |
| 662 | int ret; |
| 663 | |
| 664 | match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name, |
| 665 | m->u.user.revision), |
| 666 | "ip6t_%s", m->u.user.name); |
| 667 | if (IS_ERR(match) || !match) { |
| 668 | duprintf("find_check_match: `%s' not found\n", m->u.user.name); |
| 669 | return match ? PTR_ERR(match) : -ENOENT; |
| 670 | } |
| 671 | m->u.kernel.match = match; |
| 672 | |
| 673 | ret = check_match(m, par); |
| 674 | if (ret) |
| 675 | goto err; |
| 676 | |
| 677 | return 0; |
| 678 | err: |
| 679 | module_put(m->u.kernel.match->me); |
| 680 | return ret; |
| 681 | } |
| 682 | |
| 683 | static int check_target(struct ip6t_entry *e, struct net *net, const char *name) |
| 684 | { |
| 685 | struct ip6t_entry_target *t = ip6t_get_target(e); |
| 686 | struct xt_tgchk_param par = { |
| 687 | .net = net, |
| 688 | .table = name, |
| 689 | .entryinfo = e, |
| 690 | .target = t->u.kernel.target, |
| 691 | .targinfo = t->data, |
| 692 | .hook_mask = e->comefrom, |
| 693 | .family = NFPROTO_IPV6, |
| 694 | }; |
| 695 | int ret; |
| 696 | |
| 697 | t = ip6t_get_target(e); |
| 698 | ret = xt_check_target(&par, t->u.target_size - sizeof(*t), |
| 699 | e->ipv6.proto, e->ipv6.invflags & IP6T_INV_PROTO); |
| 700 | if (ret < 0) { |
| 701 | duprintf("ip_tables: check failed for `%s'.\n", |
| 702 | t->u.kernel.target->name); |
| 703 | return ret; |
| 704 | } |
| 705 | return 0; |
| 706 | } |
| 707 | |
| 708 | static int |
| 709 | find_check_entry(struct ip6t_entry *e, struct net *net, const char *name, |
| 710 | unsigned int size) |
| 711 | { |
| 712 | struct ip6t_entry_target *t; |
| 713 | struct xt_target *target; |
| 714 | int ret; |
| 715 | unsigned int j; |
| 716 | struct xt_mtchk_param mtpar; |
| 717 | struct xt_entry_match *ematch; |
| 718 | |
| 719 | ret = check_entry(e, name); |
| 720 | if (ret) |
| 721 | return ret; |
| 722 | |
| 723 | j = 0; |
| 724 | mtpar.net = net; |
| 725 | mtpar.table = name; |
| 726 | mtpar.entryinfo = &e->ipv6; |
| 727 | mtpar.hook_mask = e->comefrom; |
| 728 | mtpar.family = NFPROTO_IPV6; |
| 729 | xt_ematch_foreach(ematch, e) { |
| 730 | ret = find_check_match(ematch, &mtpar); |
| 731 | if (ret != 0) |
| 732 | goto cleanup_matches; |
| 733 | ++j; |
| 734 | } |
| 735 | |
| 736 | t = ip6t_get_target(e); |
| 737 | target = try_then_request_module(xt_find_target(AF_INET6, |
| 738 | t->u.user.name, |
| 739 | t->u.user.revision), |
| 740 | "ip6t_%s", t->u.user.name); |
| 741 | if (IS_ERR(target) || !target) { |
| 742 | duprintf("find_check_entry: `%s' not found\n", t->u.user.name); |
| 743 | ret = target ? PTR_ERR(target) : -ENOENT; |
| 744 | goto cleanup_matches; |
| 745 | } |
| 746 | t->u.kernel.target = target; |
| 747 | |
| 748 | ret = check_target(e, net, name); |
| 749 | if (ret) |
| 750 | goto err; |
| 751 | return 0; |
| 752 | err: |
| 753 | module_put(t->u.kernel.target->me); |
| 754 | cleanup_matches: |
| 755 | xt_ematch_foreach(ematch, e) { |
| 756 | if (j-- == 0) |
| 757 | break; |
| 758 | cleanup_match(ematch, net); |
| 759 | } |
| 760 | return ret; |
| 761 | } |
| 762 | |
| 763 | static bool check_underflow(const struct ip6t_entry *e) |
| 764 | { |
| 765 | const struct ip6t_entry_target *t; |
| 766 | unsigned int verdict; |
| 767 | |
| 768 | if (!unconditional(&e->ipv6)) |
| 769 | return false; |
| 770 | t = ip6t_get_target_c(e); |
| 771 | if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0) |
| 772 | return false; |
| 773 | verdict = ((struct ip6t_standard_target *)t)->verdict; |
| 774 | verdict = -verdict - 1; |
| 775 | return verdict == NF_DROP || verdict == NF_ACCEPT; |
| 776 | } |
| 777 | |
| 778 | static int |
| 779 | check_entry_size_and_hooks(struct ip6t_entry *e, |
| 780 | struct xt_table_info *newinfo, |
| 781 | const unsigned char *base, |
| 782 | const unsigned char *limit, |
| 783 | const unsigned int *hook_entries, |
| 784 | const unsigned int *underflows, |
| 785 | unsigned int valid_hooks) |
| 786 | { |
| 787 | unsigned int h; |
| 788 | |
| 789 | if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 || |
| 790 | (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) { |
| 791 | duprintf("Bad offset %p\n", e); |
| 792 | return -EINVAL; |
| 793 | } |
| 794 | |
| 795 | if (e->next_offset |
| 796 | < sizeof(struct ip6t_entry) + sizeof(struct ip6t_entry_target)) { |
| 797 | duprintf("checking: element %p size %u\n", |
| 798 | e, e->next_offset); |
| 799 | return -EINVAL; |
| 800 | } |
| 801 | |
| 802 | /* Check hooks & underflows */ |
| 803 | for (h = 0; h < NF_INET_NUMHOOKS; h++) { |
| 804 | if (!(valid_hooks & (1 << h))) |
| 805 | continue; |
| 806 | if ((unsigned char *)e - base == hook_entries[h]) |
| 807 | newinfo->hook_entry[h] = hook_entries[h]; |
| 808 | if ((unsigned char *)e - base == underflows[h]) { |
| 809 | if (!check_underflow(e)) { |
| 810 | pr_err("Underflows must be unconditional and " |
| 811 | "use the STANDARD target with " |
| 812 | "ACCEPT/DROP\n"); |
| 813 | return -EINVAL; |
| 814 | } |
| 815 | newinfo->underflow[h] = underflows[h]; |
| 816 | } |
| 817 | } |
| 818 | |
| 819 | /* Clear counters and comefrom */ |
| 820 | e->counters = ((struct xt_counters) { 0, 0 }); |
| 821 | e->comefrom = 0; |
| 822 | return 0; |
| 823 | } |
| 824 | |
| 825 | static void cleanup_entry(struct ip6t_entry *e, struct net *net) |
| 826 | { |
| 827 | struct xt_tgdtor_param par; |
| 828 | struct ip6t_entry_target *t; |
| 829 | struct xt_entry_match *ematch; |
| 830 | |
| 831 | /* Cleanup all matches */ |
| 832 | xt_ematch_foreach(ematch, e) |
| 833 | cleanup_match(ematch, net); |
| 834 | t = ip6t_get_target(e); |
| 835 | |
| 836 | par.net = net; |
| 837 | par.target = t->u.kernel.target; |
| 838 | par.targinfo = t->data; |
| 839 | par.family = NFPROTO_IPV6; |
| 840 | if (par.target->destroy != NULL) |
| 841 | par.target->destroy(&par); |
| 842 | module_put(par.target->me); |
| 843 | } |
| 844 | |
| 845 | /* Checks and translates the user-supplied table segment (held in |
| 846 | newinfo) */ |
| 847 | static int |
| 848 | translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, |
| 849 | const struct ip6t_replace *repl) |
| 850 | { |
| 851 | struct ip6t_entry *iter; |
| 852 | unsigned int i; |
| 853 | int ret = 0; |
| 854 | |
| 855 | newinfo->size = repl->size; |
| 856 | newinfo->number = repl->num_entries; |
| 857 | |
| 858 | /* Init all hooks to impossible value. */ |
| 859 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 860 | newinfo->hook_entry[i] = 0xFFFFFFFF; |
| 861 | newinfo->underflow[i] = 0xFFFFFFFF; |
| 862 | } |
| 863 | |
| 864 | duprintf("translate_table: size %u\n", newinfo->size); |
| 865 | i = 0; |
| 866 | /* Walk through entries, checking offsets. */ |
| 867 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 868 | ret = check_entry_size_and_hooks(iter, newinfo, entry0, |
| 869 | entry0 + repl->size, |
| 870 | repl->hook_entry, |
| 871 | repl->underflow, |
| 872 | repl->valid_hooks); |
| 873 | if (ret != 0) |
| 874 | return ret; |
| 875 | ++i; |
| 876 | } |
| 877 | |
| 878 | if (i != repl->num_entries) { |
| 879 | duprintf("translate_table: %u not %u entries\n", |
| 880 | i, repl->num_entries); |
| 881 | return -EINVAL; |
| 882 | } |
| 883 | |
| 884 | /* Check hooks all assigned */ |
| 885 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 886 | /* Only hooks which are valid */ |
| 887 | if (!(repl->valid_hooks & (1 << i))) |
| 888 | continue; |
| 889 | if (newinfo->hook_entry[i] == 0xFFFFFFFF) { |
| 890 | duprintf("Invalid hook entry %u %u\n", |
| 891 | i, repl->hook_entry[i]); |
| 892 | return -EINVAL; |
| 893 | } |
| 894 | if (newinfo->underflow[i] == 0xFFFFFFFF) { |
| 895 | duprintf("Invalid underflow %u %u\n", |
| 896 | i, repl->underflow[i]); |
| 897 | return -EINVAL; |
| 898 | } |
| 899 | } |
| 900 | |
| 901 | if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) |
| 902 | return -ELOOP; |
| 903 | |
| 904 | /* Finally, each sanity check must pass */ |
| 905 | i = 0; |
| 906 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 907 | ret = find_check_entry(iter, net, repl->name, repl->size); |
| 908 | if (ret != 0) |
| 909 | break; |
| 910 | ++i; |
| 911 | } |
| 912 | |
| 913 | if (ret != 0) { |
| 914 | xt_entry_foreach(iter, entry0, newinfo->size) { |
| 915 | if (i-- == 0) |
| 916 | break; |
| 917 | cleanup_entry(iter, net); |
| 918 | } |
| 919 | return ret; |
| 920 | } |
| 921 | |
| 922 | /* And one copy for every other CPU */ |
| 923 | for_each_possible_cpu(i) { |
| 924 | if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
| 925 | memcpy(newinfo->entries[i], entry0, newinfo->size); |
| 926 | } |
| 927 | |
| 928 | return ret; |
| 929 | } |
| 930 | |
| 931 | static void |
| 932 | get_counters(const struct xt_table_info *t, |
| 933 | struct xt_counters counters[]) |
| 934 | { |
| 935 | struct ip6t_entry *iter; |
| 936 | unsigned int cpu; |
| 937 | unsigned int i; |
| 938 | unsigned int curcpu; |
| 939 | |
| 940 | /* Instead of clearing (by a previous call to memset()) |
| 941 | * the counters and using adds, we set the counters |
| 942 | * with data used by 'current' CPU |
| 943 | * |
| 944 | * Bottom half has to be disabled to prevent deadlock |
| 945 | * if new softirq were to run and call ipt_do_table |
| 946 | */ |
| 947 | local_bh_disable(); |
| 948 | curcpu = smp_processor_id(); |
| 949 | |
| 950 | i = 0; |
| 951 | xt_entry_foreach(iter, t->entries[curcpu], t->size) { |
| 952 | SET_COUNTER(counters[i], iter->counters.bcnt, |
| 953 | iter->counters.pcnt); |
| 954 | ++i; |
| 955 | } |
| 956 | |
| 957 | for_each_possible_cpu(cpu) { |
| 958 | if (cpu == curcpu) |
| 959 | continue; |
| 960 | i = 0; |
| 961 | xt_info_wrlock(cpu); |
| 962 | xt_entry_foreach(iter, t->entries[cpu], t->size) { |
| 963 | ADD_COUNTER(counters[i], iter->counters.bcnt, |
| 964 | iter->counters.pcnt); |
| 965 | ++i; |
| 966 | } |
| 967 | xt_info_wrunlock(cpu); |
| 968 | } |
| 969 | local_bh_enable(); |
| 970 | } |
| 971 | |
| 972 | static struct xt_counters *alloc_counters(const struct xt_table *table) |
| 973 | { |
| 974 | unsigned int countersize; |
| 975 | struct xt_counters *counters; |
| 976 | const struct xt_table_info *private = table->private; |
| 977 | |
| 978 | /* We need atomic snapshot of counters: rest doesn't change |
| 979 | (other than comefrom, which userspace doesn't care |
| 980 | about). */ |
| 981 | countersize = sizeof(struct xt_counters) * private->number; |
| 982 | counters = vmalloc_node(countersize, numa_node_id()); |
| 983 | |
| 984 | if (counters == NULL) |
| 985 | return ERR_PTR(-ENOMEM); |
| 986 | |
| 987 | get_counters(private, counters); |
| 988 | |
| 989 | return counters; |
| 990 | } |
| 991 | |
| 992 | static int |
| 993 | copy_entries_to_user(unsigned int total_size, |
| 994 | const struct xt_table *table, |
| 995 | void __user *userptr) |
| 996 | { |
| 997 | unsigned int off, num; |
| 998 | const struct ip6t_entry *e; |
| 999 | struct xt_counters *counters; |
| 1000 | const struct xt_table_info *private = table->private; |
| 1001 | int ret = 0; |
| 1002 | const void *loc_cpu_entry; |
| 1003 | |
| 1004 | counters = alloc_counters(table); |
| 1005 | if (IS_ERR(counters)) |
| 1006 | return PTR_ERR(counters); |
| 1007 | |
| 1008 | /* choose the copy that is on our node/cpu, ... |
| 1009 | * This choice is lazy (because current thread is |
| 1010 | * allowed to migrate to another cpu) |
| 1011 | */ |
| 1012 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
| 1013 | if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { |
| 1014 | ret = -EFAULT; |
| 1015 | goto free_counters; |
| 1016 | } |
| 1017 | |
| 1018 | /* FIXME: use iterator macros --RR */ |
| 1019 | /* ... then go back and fix counters and names */ |
| 1020 | for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ |
| 1021 | unsigned int i; |
| 1022 | const struct ip6t_entry_match *m; |
| 1023 | const struct ip6t_entry_target *t; |
| 1024 | |
| 1025 | e = (struct ip6t_entry *)(loc_cpu_entry + off); |
| 1026 | if (copy_to_user(userptr + off |
| 1027 | + offsetof(struct ip6t_entry, counters), |
| 1028 | &counters[num], |
| 1029 | sizeof(counters[num])) != 0) { |
| 1030 | ret = -EFAULT; |
| 1031 | goto free_counters; |
| 1032 | } |
| 1033 | |
| 1034 | for (i = sizeof(struct ip6t_entry); |
| 1035 | i < e->target_offset; |
| 1036 | i += m->u.match_size) { |
| 1037 | m = (void *)e + i; |
| 1038 | |
| 1039 | if (copy_to_user(userptr + off + i |
| 1040 | + offsetof(struct ip6t_entry_match, |
| 1041 | u.user.name), |
| 1042 | m->u.kernel.match->name, |
| 1043 | strlen(m->u.kernel.match->name)+1) |
| 1044 | != 0) { |
| 1045 | ret = -EFAULT; |
| 1046 | goto free_counters; |
| 1047 | } |
| 1048 | } |
| 1049 | |
| 1050 | t = ip6t_get_target_c(e); |
| 1051 | if (copy_to_user(userptr + off + e->target_offset |
| 1052 | + offsetof(struct ip6t_entry_target, |
| 1053 | u.user.name), |
| 1054 | t->u.kernel.target->name, |
| 1055 | strlen(t->u.kernel.target->name)+1) != 0) { |
| 1056 | ret = -EFAULT; |
| 1057 | goto free_counters; |
| 1058 | } |
| 1059 | } |
| 1060 | |
| 1061 | free_counters: |
| 1062 | vfree(counters); |
| 1063 | return ret; |
| 1064 | } |
| 1065 | |
| 1066 | #ifdef CONFIG_COMPAT |
| 1067 | static void compat_standard_from_user(void *dst, const void *src) |
| 1068 | { |
| 1069 | int v = *(compat_int_t *)src; |
| 1070 | |
| 1071 | if (v > 0) |
| 1072 | v += xt_compat_calc_jump(AF_INET6, v); |
| 1073 | memcpy(dst, &v, sizeof(v)); |
| 1074 | } |
| 1075 | |
| 1076 | static int compat_standard_to_user(void __user *dst, const void *src) |
| 1077 | { |
| 1078 | compat_int_t cv = *(int *)src; |
| 1079 | |
| 1080 | if (cv > 0) |
| 1081 | cv -= xt_compat_calc_jump(AF_INET6, cv); |
| 1082 | return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0; |
| 1083 | } |
| 1084 | |
| 1085 | static int compat_calc_entry(const struct ip6t_entry *e, |
| 1086 | const struct xt_table_info *info, |
| 1087 | const void *base, struct xt_table_info *newinfo) |
| 1088 | { |
| 1089 | const struct xt_entry_match *ematch; |
| 1090 | const struct ip6t_entry_target *t; |
| 1091 | unsigned int entry_offset; |
| 1092 | int off, i, ret; |
| 1093 | |
| 1094 | off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1095 | entry_offset = (void *)e - base; |
| 1096 | xt_ematch_foreach(ematch, e) |
| 1097 | off += xt_compat_match_offset(ematch->u.kernel.match); |
| 1098 | t = ip6t_get_target_c(e); |
| 1099 | off += xt_compat_target_offset(t->u.kernel.target); |
| 1100 | newinfo->size -= off; |
| 1101 | ret = xt_compat_add_offset(AF_INET6, entry_offset, off); |
| 1102 | if (ret) |
| 1103 | return ret; |
| 1104 | |
| 1105 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1106 | if (info->hook_entry[i] && |
| 1107 | (e < (struct ip6t_entry *)(base + info->hook_entry[i]))) |
| 1108 | newinfo->hook_entry[i] -= off; |
| 1109 | if (info->underflow[i] && |
| 1110 | (e < (struct ip6t_entry *)(base + info->underflow[i]))) |
| 1111 | newinfo->underflow[i] -= off; |
| 1112 | } |
| 1113 | return 0; |
| 1114 | } |
| 1115 | |
| 1116 | static int compat_table_info(const struct xt_table_info *info, |
| 1117 | struct xt_table_info *newinfo) |
| 1118 | { |
| 1119 | struct ip6t_entry *iter; |
| 1120 | void *loc_cpu_entry; |
| 1121 | int ret; |
| 1122 | |
| 1123 | if (!newinfo || !info) |
| 1124 | return -EINVAL; |
| 1125 | |
| 1126 | /* we dont care about newinfo->entries[] */ |
| 1127 | memcpy(newinfo, info, offsetof(struct xt_table_info, entries)); |
| 1128 | newinfo->initial_entries = 0; |
| 1129 | loc_cpu_entry = info->entries[raw_smp_processor_id()]; |
| 1130 | xt_entry_foreach(iter, loc_cpu_entry, info->size) { |
| 1131 | ret = compat_calc_entry(iter, info, loc_cpu_entry, newinfo); |
| 1132 | if (ret != 0) |
| 1133 | return ret; |
| 1134 | } |
| 1135 | return 0; |
| 1136 | } |
| 1137 | #endif |
| 1138 | |
| 1139 | static int get_info(struct net *net, void __user *user, |
| 1140 | const int *len, int compat) |
| 1141 | { |
| 1142 | char name[IP6T_TABLE_MAXNAMELEN]; |
| 1143 | struct xt_table *t; |
| 1144 | int ret; |
| 1145 | |
| 1146 | if (*len != sizeof(struct ip6t_getinfo)) { |
| 1147 | duprintf("length %u != %zu\n", *len, |
| 1148 | sizeof(struct ip6t_getinfo)); |
| 1149 | return -EINVAL; |
| 1150 | } |
| 1151 | |
| 1152 | if (copy_from_user(name, user, sizeof(name)) != 0) |
| 1153 | return -EFAULT; |
| 1154 | |
| 1155 | name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; |
| 1156 | #ifdef CONFIG_COMPAT |
| 1157 | if (compat) |
| 1158 | xt_compat_lock(AF_INET6); |
| 1159 | #endif |
| 1160 | t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), |
| 1161 | "ip6table_%s", name); |
| 1162 | if (t && !IS_ERR(t)) { |
| 1163 | struct ip6t_getinfo info; |
| 1164 | const struct xt_table_info *private = t->private; |
| 1165 | #ifdef CONFIG_COMPAT |
| 1166 | struct xt_table_info tmp; |
| 1167 | |
| 1168 | if (compat) { |
| 1169 | ret = compat_table_info(private, &tmp); |
| 1170 | xt_compat_flush_offsets(AF_INET6); |
| 1171 | private = &tmp; |
| 1172 | } |
| 1173 | #endif |
| 1174 | info.valid_hooks = t->valid_hooks; |
| 1175 | memcpy(info.hook_entry, private->hook_entry, |
| 1176 | sizeof(info.hook_entry)); |
| 1177 | memcpy(info.underflow, private->underflow, |
| 1178 | sizeof(info.underflow)); |
| 1179 | info.num_entries = private->number; |
| 1180 | info.size = private->size; |
| 1181 | strcpy(info.name, name); |
| 1182 | |
| 1183 | if (copy_to_user(user, &info, *len) != 0) |
| 1184 | ret = -EFAULT; |
| 1185 | else |
| 1186 | ret = 0; |
| 1187 | |
| 1188 | xt_table_unlock(t); |
| 1189 | module_put(t->me); |
| 1190 | } else |
| 1191 | ret = t ? PTR_ERR(t) : -ENOENT; |
| 1192 | #ifdef CONFIG_COMPAT |
| 1193 | if (compat) |
| 1194 | xt_compat_unlock(AF_INET6); |
| 1195 | #endif |
| 1196 | return ret; |
| 1197 | } |
| 1198 | |
| 1199 | static int |
| 1200 | get_entries(struct net *net, struct ip6t_get_entries __user *uptr, |
| 1201 | const int *len) |
| 1202 | { |
| 1203 | int ret; |
| 1204 | struct ip6t_get_entries get; |
| 1205 | struct xt_table *t; |
| 1206 | |
| 1207 | if (*len < sizeof(get)) { |
| 1208 | duprintf("get_entries: %u < %zu\n", *len, sizeof(get)); |
| 1209 | return -EINVAL; |
| 1210 | } |
| 1211 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) |
| 1212 | return -EFAULT; |
| 1213 | if (*len != sizeof(struct ip6t_get_entries) + get.size) { |
| 1214 | duprintf("get_entries: %u != %zu\n", |
| 1215 | *len, sizeof(get) + get.size); |
| 1216 | return -EINVAL; |
| 1217 | } |
| 1218 | |
| 1219 | t = xt_find_table_lock(net, AF_INET6, get.name); |
| 1220 | if (t && !IS_ERR(t)) { |
| 1221 | struct xt_table_info *private = t->private; |
| 1222 | duprintf("t->private->number = %u\n", private->number); |
| 1223 | if (get.size == private->size) |
| 1224 | ret = copy_entries_to_user(private->size, |
| 1225 | t, uptr->entrytable); |
| 1226 | else { |
| 1227 | duprintf("get_entries: I've got %u not %u!\n", |
| 1228 | private->size, get.size); |
| 1229 | ret = -EAGAIN; |
| 1230 | } |
| 1231 | module_put(t->me); |
| 1232 | xt_table_unlock(t); |
| 1233 | } else |
| 1234 | ret = t ? PTR_ERR(t) : -ENOENT; |
| 1235 | |
| 1236 | return ret; |
| 1237 | } |
| 1238 | |
| 1239 | static int |
| 1240 | __do_replace(struct net *net, const char *name, unsigned int valid_hooks, |
| 1241 | struct xt_table_info *newinfo, unsigned int num_counters, |
| 1242 | void __user *counters_ptr) |
| 1243 | { |
| 1244 | int ret; |
| 1245 | struct xt_table *t; |
| 1246 | struct xt_table_info *oldinfo; |
| 1247 | struct xt_counters *counters; |
| 1248 | const void *loc_cpu_old_entry; |
| 1249 | struct ip6t_entry *iter; |
| 1250 | |
| 1251 | ret = 0; |
| 1252 | counters = vmalloc_node(num_counters * sizeof(struct xt_counters), |
| 1253 | numa_node_id()); |
| 1254 | if (!counters) { |
| 1255 | ret = -ENOMEM; |
| 1256 | goto out; |
| 1257 | } |
| 1258 | |
| 1259 | t = try_then_request_module(xt_find_table_lock(net, AF_INET6, name), |
| 1260 | "ip6table_%s", name); |
| 1261 | if (!t || IS_ERR(t)) { |
| 1262 | ret = t ? PTR_ERR(t) : -ENOENT; |
| 1263 | goto free_newinfo_counters_untrans; |
| 1264 | } |
| 1265 | |
| 1266 | /* You lied! */ |
| 1267 | if (valid_hooks != t->valid_hooks) { |
| 1268 | duprintf("Valid hook crap: %08X vs %08X\n", |
| 1269 | valid_hooks, t->valid_hooks); |
| 1270 | ret = -EINVAL; |
| 1271 | goto put_module; |
| 1272 | } |
| 1273 | |
| 1274 | oldinfo = xt_replace_table(t, num_counters, newinfo, &ret); |
| 1275 | if (!oldinfo) |
| 1276 | goto put_module; |
| 1277 | |
| 1278 | /* Update module usage count based on number of rules */ |
| 1279 | duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", |
| 1280 | oldinfo->number, oldinfo->initial_entries, newinfo->number); |
| 1281 | if ((oldinfo->number > oldinfo->initial_entries) || |
| 1282 | (newinfo->number <= oldinfo->initial_entries)) |
| 1283 | module_put(t->me); |
| 1284 | if ((oldinfo->number > oldinfo->initial_entries) && |
| 1285 | (newinfo->number <= oldinfo->initial_entries)) |
| 1286 | module_put(t->me); |
| 1287 | |
| 1288 | /* Get the old counters, and synchronize with replace */ |
| 1289 | get_counters(oldinfo, counters); |
| 1290 | |
| 1291 | /* Decrease module usage counts and free resource */ |
| 1292 | loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
| 1293 | xt_entry_foreach(iter, loc_cpu_old_entry, oldinfo->size) |
| 1294 | cleanup_entry(iter, net); |
| 1295 | |
| 1296 | xt_free_table_info(oldinfo); |
| 1297 | if (copy_to_user(counters_ptr, counters, |
| 1298 | sizeof(struct xt_counters) * num_counters) != 0) |
| 1299 | ret = -EFAULT; |
| 1300 | vfree(counters); |
| 1301 | xt_table_unlock(t); |
| 1302 | return ret; |
| 1303 | |
| 1304 | put_module: |
| 1305 | module_put(t->me); |
| 1306 | xt_table_unlock(t); |
| 1307 | free_newinfo_counters_untrans: |
| 1308 | vfree(counters); |
| 1309 | out: |
| 1310 | return ret; |
| 1311 | } |
| 1312 | |
| 1313 | static int |
| 1314 | do_replace(struct net *net, const void __user *user, unsigned int len) |
| 1315 | { |
| 1316 | int ret; |
| 1317 | struct ip6t_replace tmp; |
| 1318 | struct xt_table_info *newinfo; |
| 1319 | void *loc_cpu_entry; |
| 1320 | struct ip6t_entry *iter; |
| 1321 | |
| 1322 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| 1323 | return -EFAULT; |
| 1324 | |
| 1325 | /* overflow check */ |
| 1326 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) |
| 1327 | return -ENOMEM; |
| 1328 | |
| 1329 | newinfo = xt_alloc_table_info(tmp.size); |
| 1330 | if (!newinfo) |
| 1331 | return -ENOMEM; |
| 1332 | |
| 1333 | /* choose the copy that is on our node/cpu */ |
| 1334 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; |
| 1335 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
| 1336 | tmp.size) != 0) { |
| 1337 | ret = -EFAULT; |
| 1338 | goto free_newinfo; |
| 1339 | } |
| 1340 | |
| 1341 | ret = translate_table(net, newinfo, loc_cpu_entry, &tmp); |
| 1342 | if (ret != 0) |
| 1343 | goto free_newinfo; |
| 1344 | |
| 1345 | duprintf("ip_tables: Translated table\n"); |
| 1346 | |
| 1347 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
| 1348 | tmp.num_counters, tmp.counters); |
| 1349 | if (ret) |
| 1350 | goto free_newinfo_untrans; |
| 1351 | return 0; |
| 1352 | |
| 1353 | free_newinfo_untrans: |
| 1354 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
| 1355 | cleanup_entry(iter, net); |
| 1356 | free_newinfo: |
| 1357 | xt_free_table_info(newinfo); |
| 1358 | return ret; |
| 1359 | } |
| 1360 | |
| 1361 | static int |
| 1362 | do_add_counters(struct net *net, const void __user *user, unsigned int len, |
| 1363 | int compat) |
| 1364 | { |
| 1365 | unsigned int i, curcpu; |
| 1366 | struct xt_counters_info tmp; |
| 1367 | struct xt_counters *paddc; |
| 1368 | unsigned int num_counters; |
| 1369 | char *name; |
| 1370 | int size; |
| 1371 | void *ptmp; |
| 1372 | struct xt_table *t; |
| 1373 | const struct xt_table_info *private; |
| 1374 | int ret = 0; |
| 1375 | const void *loc_cpu_entry; |
| 1376 | struct ip6t_entry *iter; |
| 1377 | #ifdef CONFIG_COMPAT |
| 1378 | struct compat_xt_counters_info compat_tmp; |
| 1379 | |
| 1380 | if (compat) { |
| 1381 | ptmp = &compat_tmp; |
| 1382 | size = sizeof(struct compat_xt_counters_info); |
| 1383 | } else |
| 1384 | #endif |
| 1385 | { |
| 1386 | ptmp = &tmp; |
| 1387 | size = sizeof(struct xt_counters_info); |
| 1388 | } |
| 1389 | |
| 1390 | if (copy_from_user(ptmp, user, size) != 0) |
| 1391 | return -EFAULT; |
| 1392 | |
| 1393 | #ifdef CONFIG_COMPAT |
| 1394 | if (compat) { |
| 1395 | num_counters = compat_tmp.num_counters; |
| 1396 | name = compat_tmp.name; |
| 1397 | } else |
| 1398 | #endif |
| 1399 | { |
| 1400 | num_counters = tmp.num_counters; |
| 1401 | name = tmp.name; |
| 1402 | } |
| 1403 | |
| 1404 | if (len != size + num_counters * sizeof(struct xt_counters)) |
| 1405 | return -EINVAL; |
| 1406 | |
| 1407 | paddc = vmalloc_node(len - size, numa_node_id()); |
| 1408 | if (!paddc) |
| 1409 | return -ENOMEM; |
| 1410 | |
| 1411 | if (copy_from_user(paddc, user + size, len - size) != 0) { |
| 1412 | ret = -EFAULT; |
| 1413 | goto free; |
| 1414 | } |
| 1415 | |
| 1416 | t = xt_find_table_lock(net, AF_INET6, name); |
| 1417 | if (!t || IS_ERR(t)) { |
| 1418 | ret = t ? PTR_ERR(t) : -ENOENT; |
| 1419 | goto free; |
| 1420 | } |
| 1421 | |
| 1422 | |
| 1423 | local_bh_disable(); |
| 1424 | private = t->private; |
| 1425 | if (private->number != num_counters) { |
| 1426 | ret = -EINVAL; |
| 1427 | goto unlock_up_free; |
| 1428 | } |
| 1429 | |
| 1430 | i = 0; |
| 1431 | /* Choose the copy that is on our node */ |
| 1432 | curcpu = smp_processor_id(); |
| 1433 | xt_info_wrlock(curcpu); |
| 1434 | loc_cpu_entry = private->entries[curcpu]; |
| 1435 | xt_entry_foreach(iter, loc_cpu_entry, private->size) { |
| 1436 | ADD_COUNTER(iter->counters, paddc[i].bcnt, paddc[i].pcnt); |
| 1437 | ++i; |
| 1438 | } |
| 1439 | xt_info_wrunlock(curcpu); |
| 1440 | |
| 1441 | unlock_up_free: |
| 1442 | local_bh_enable(); |
| 1443 | xt_table_unlock(t); |
| 1444 | module_put(t->me); |
| 1445 | free: |
| 1446 | vfree(paddc); |
| 1447 | |
| 1448 | return ret; |
| 1449 | } |
| 1450 | |
| 1451 | #ifdef CONFIG_COMPAT |
| 1452 | struct compat_ip6t_replace { |
| 1453 | char name[IP6T_TABLE_MAXNAMELEN]; |
| 1454 | u32 valid_hooks; |
| 1455 | u32 num_entries; |
| 1456 | u32 size; |
| 1457 | u32 hook_entry[NF_INET_NUMHOOKS]; |
| 1458 | u32 underflow[NF_INET_NUMHOOKS]; |
| 1459 | u32 num_counters; |
| 1460 | compat_uptr_t counters; /* struct ip6t_counters * */ |
| 1461 | struct compat_ip6t_entry entries[0]; |
| 1462 | }; |
| 1463 | |
| 1464 | static int |
| 1465 | compat_copy_entry_to_user(struct ip6t_entry *e, void __user **dstptr, |
| 1466 | unsigned int *size, struct xt_counters *counters, |
| 1467 | unsigned int i) |
| 1468 | { |
| 1469 | struct ip6t_entry_target *t; |
| 1470 | struct compat_ip6t_entry __user *ce; |
| 1471 | u_int16_t target_offset, next_offset; |
| 1472 | compat_uint_t origsize; |
| 1473 | const struct xt_entry_match *ematch; |
| 1474 | int ret = 0; |
| 1475 | |
| 1476 | origsize = *size; |
| 1477 | ce = (struct compat_ip6t_entry __user *)*dstptr; |
| 1478 | if (copy_to_user(ce, e, sizeof(struct ip6t_entry)) != 0 || |
| 1479 | copy_to_user(&ce->counters, &counters[i], |
| 1480 | sizeof(counters[i])) != 0) |
| 1481 | return -EFAULT; |
| 1482 | |
| 1483 | *dstptr += sizeof(struct compat_ip6t_entry); |
| 1484 | *size -= sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1485 | |
| 1486 | xt_ematch_foreach(ematch, e) { |
| 1487 | ret = xt_compat_match_to_user(ematch, dstptr, size); |
| 1488 | if (ret != 0) |
| 1489 | return ret; |
| 1490 | } |
| 1491 | target_offset = e->target_offset - (origsize - *size); |
| 1492 | t = ip6t_get_target(e); |
| 1493 | ret = xt_compat_target_to_user(t, dstptr, size); |
| 1494 | if (ret) |
| 1495 | return ret; |
| 1496 | next_offset = e->next_offset - (origsize - *size); |
| 1497 | if (put_user(target_offset, &ce->target_offset) != 0 || |
| 1498 | put_user(next_offset, &ce->next_offset) != 0) |
| 1499 | return -EFAULT; |
| 1500 | return 0; |
| 1501 | } |
| 1502 | |
| 1503 | static int |
| 1504 | compat_find_calc_match(struct ip6t_entry_match *m, |
| 1505 | const char *name, |
| 1506 | const struct ip6t_ip6 *ipv6, |
| 1507 | unsigned int hookmask, |
| 1508 | int *size) |
| 1509 | { |
| 1510 | struct xt_match *match; |
| 1511 | |
| 1512 | match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name, |
| 1513 | m->u.user.revision), |
| 1514 | "ip6t_%s", m->u.user.name); |
| 1515 | if (IS_ERR(match) || !match) { |
| 1516 | duprintf("compat_check_calc_match: `%s' not found\n", |
| 1517 | m->u.user.name); |
| 1518 | return match ? PTR_ERR(match) : -ENOENT; |
| 1519 | } |
| 1520 | m->u.kernel.match = match; |
| 1521 | *size += xt_compat_match_offset(match); |
| 1522 | return 0; |
| 1523 | } |
| 1524 | |
| 1525 | static void compat_release_entry(struct compat_ip6t_entry *e) |
| 1526 | { |
| 1527 | struct ip6t_entry_target *t; |
| 1528 | struct xt_entry_match *ematch; |
| 1529 | |
| 1530 | /* Cleanup all matches */ |
| 1531 | xt_ematch_foreach(ematch, e) |
| 1532 | module_put(ematch->u.kernel.match->me); |
| 1533 | t = compat_ip6t_get_target(e); |
| 1534 | module_put(t->u.kernel.target->me); |
| 1535 | } |
| 1536 | |
| 1537 | static int |
| 1538 | check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e, |
| 1539 | struct xt_table_info *newinfo, |
| 1540 | unsigned int *size, |
| 1541 | const unsigned char *base, |
| 1542 | const unsigned char *limit, |
| 1543 | const unsigned int *hook_entries, |
| 1544 | const unsigned int *underflows, |
| 1545 | const char *name) |
| 1546 | { |
| 1547 | struct xt_entry_match *ematch; |
| 1548 | struct ip6t_entry_target *t; |
| 1549 | struct xt_target *target; |
| 1550 | unsigned int entry_offset; |
| 1551 | unsigned int j; |
| 1552 | int ret, off, h; |
| 1553 | |
| 1554 | duprintf("check_compat_entry_size_and_hooks %p\n", e); |
| 1555 | if ((unsigned long)e % __alignof__(struct compat_ip6t_entry) != 0 || |
| 1556 | (unsigned char *)e + sizeof(struct compat_ip6t_entry) >= limit) { |
| 1557 | duprintf("Bad offset %p, limit = %p\n", e, limit); |
| 1558 | return -EINVAL; |
| 1559 | } |
| 1560 | |
| 1561 | if (e->next_offset < sizeof(struct compat_ip6t_entry) + |
| 1562 | sizeof(struct compat_xt_entry_target)) { |
| 1563 | duprintf("checking: element %p size %u\n", |
| 1564 | e, e->next_offset); |
| 1565 | return -EINVAL; |
| 1566 | } |
| 1567 | |
| 1568 | /* For purposes of check_entry casting the compat entry is fine */ |
| 1569 | ret = check_entry((struct ip6t_entry *)e, name); |
| 1570 | if (ret) |
| 1571 | return ret; |
| 1572 | |
| 1573 | off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1574 | entry_offset = (void *)e - (void *)base; |
| 1575 | j = 0; |
| 1576 | xt_ematch_foreach(ematch, e) { |
| 1577 | ret = compat_find_calc_match(ematch, name, |
| 1578 | &e->ipv6, e->comefrom, &off); |
| 1579 | if (ret != 0) |
| 1580 | goto release_matches; |
| 1581 | ++j; |
| 1582 | } |
| 1583 | |
| 1584 | t = compat_ip6t_get_target(e); |
| 1585 | target = try_then_request_module(xt_find_target(AF_INET6, |
| 1586 | t->u.user.name, |
| 1587 | t->u.user.revision), |
| 1588 | "ip6t_%s", t->u.user.name); |
| 1589 | if (IS_ERR(target) || !target) { |
| 1590 | duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", |
| 1591 | t->u.user.name); |
| 1592 | ret = target ? PTR_ERR(target) : -ENOENT; |
| 1593 | goto release_matches; |
| 1594 | } |
| 1595 | t->u.kernel.target = target; |
| 1596 | |
| 1597 | off += xt_compat_target_offset(target); |
| 1598 | *size += off; |
| 1599 | ret = xt_compat_add_offset(AF_INET6, entry_offset, off); |
| 1600 | if (ret) |
| 1601 | goto out; |
| 1602 | |
| 1603 | /* Check hooks & underflows */ |
| 1604 | for (h = 0; h < NF_INET_NUMHOOKS; h++) { |
| 1605 | if ((unsigned char *)e - base == hook_entries[h]) |
| 1606 | newinfo->hook_entry[h] = hook_entries[h]; |
| 1607 | if ((unsigned char *)e - base == underflows[h]) |
| 1608 | newinfo->underflow[h] = underflows[h]; |
| 1609 | } |
| 1610 | |
| 1611 | /* Clear counters and comefrom */ |
| 1612 | memset(&e->counters, 0, sizeof(e->counters)); |
| 1613 | e->comefrom = 0; |
| 1614 | return 0; |
| 1615 | |
| 1616 | out: |
| 1617 | module_put(t->u.kernel.target->me); |
| 1618 | release_matches: |
| 1619 | xt_ematch_foreach(ematch, e) { |
| 1620 | if (j-- == 0) |
| 1621 | break; |
| 1622 | module_put(ematch->u.kernel.match->me); |
| 1623 | } |
| 1624 | return ret; |
| 1625 | } |
| 1626 | |
| 1627 | static int |
| 1628 | compat_copy_entry_from_user(struct compat_ip6t_entry *e, void **dstptr, |
| 1629 | unsigned int *size, const char *name, |
| 1630 | struct xt_table_info *newinfo, unsigned char *base) |
| 1631 | { |
| 1632 | struct ip6t_entry_target *t; |
| 1633 | struct xt_target *target; |
| 1634 | struct ip6t_entry *de; |
| 1635 | unsigned int origsize; |
| 1636 | int ret, h; |
| 1637 | struct xt_entry_match *ematch; |
| 1638 | |
| 1639 | ret = 0; |
| 1640 | origsize = *size; |
| 1641 | de = (struct ip6t_entry *)*dstptr; |
| 1642 | memcpy(de, e, sizeof(struct ip6t_entry)); |
| 1643 | memcpy(&de->counters, &e->counters, sizeof(e->counters)); |
| 1644 | |
| 1645 | *dstptr += sizeof(struct ip6t_entry); |
| 1646 | *size += sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry); |
| 1647 | |
| 1648 | xt_ematch_foreach(ematch, e) { |
| 1649 | ret = xt_compat_match_from_user(ematch, dstptr, size); |
| 1650 | if (ret != 0) |
| 1651 | return ret; |
| 1652 | } |
| 1653 | de->target_offset = e->target_offset - (origsize - *size); |
| 1654 | t = compat_ip6t_get_target(e); |
| 1655 | target = t->u.kernel.target; |
| 1656 | xt_compat_target_from_user(t, dstptr, size); |
| 1657 | |
| 1658 | de->next_offset = e->next_offset - (origsize - *size); |
| 1659 | for (h = 0; h < NF_INET_NUMHOOKS; h++) { |
| 1660 | if ((unsigned char *)de - base < newinfo->hook_entry[h]) |
| 1661 | newinfo->hook_entry[h] -= origsize - *size; |
| 1662 | if ((unsigned char *)de - base < newinfo->underflow[h]) |
| 1663 | newinfo->underflow[h] -= origsize - *size; |
| 1664 | } |
| 1665 | return ret; |
| 1666 | } |
| 1667 | |
| 1668 | static int compat_check_entry(struct ip6t_entry *e, struct net *net, |
| 1669 | const char *name) |
| 1670 | { |
| 1671 | unsigned int j; |
| 1672 | int ret = 0; |
| 1673 | struct xt_mtchk_param mtpar; |
| 1674 | struct xt_entry_match *ematch; |
| 1675 | |
| 1676 | j = 0; |
| 1677 | mtpar.net = net; |
| 1678 | mtpar.table = name; |
| 1679 | mtpar.entryinfo = &e->ipv6; |
| 1680 | mtpar.hook_mask = e->comefrom; |
| 1681 | mtpar.family = NFPROTO_IPV6; |
| 1682 | xt_ematch_foreach(ematch, e) { |
| 1683 | ret = check_match(ematch, &mtpar); |
| 1684 | if (ret != 0) |
| 1685 | goto cleanup_matches; |
| 1686 | ++j; |
| 1687 | } |
| 1688 | |
| 1689 | ret = check_target(e, net, name); |
| 1690 | if (ret) |
| 1691 | goto cleanup_matches; |
| 1692 | return 0; |
| 1693 | |
| 1694 | cleanup_matches: |
| 1695 | xt_ematch_foreach(ematch, e) { |
| 1696 | if (j-- == 0) |
| 1697 | break; |
| 1698 | cleanup_match(ematch, net); |
| 1699 | } |
| 1700 | return ret; |
| 1701 | } |
| 1702 | |
| 1703 | static int |
| 1704 | translate_compat_table(struct net *net, |
| 1705 | const char *name, |
| 1706 | unsigned int valid_hooks, |
| 1707 | struct xt_table_info **pinfo, |
| 1708 | void **pentry0, |
| 1709 | unsigned int total_size, |
| 1710 | unsigned int number, |
| 1711 | unsigned int *hook_entries, |
| 1712 | unsigned int *underflows) |
| 1713 | { |
| 1714 | unsigned int i, j; |
| 1715 | struct xt_table_info *newinfo, *info; |
| 1716 | void *pos, *entry0, *entry1; |
| 1717 | struct compat_ip6t_entry *iter0; |
| 1718 | struct ip6t_entry *iter1; |
| 1719 | unsigned int size; |
| 1720 | int ret = 0; |
| 1721 | |
| 1722 | info = *pinfo; |
| 1723 | entry0 = *pentry0; |
| 1724 | size = total_size; |
| 1725 | info->number = number; |
| 1726 | |
| 1727 | /* Init all hooks to impossible value. */ |
| 1728 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1729 | info->hook_entry[i] = 0xFFFFFFFF; |
| 1730 | info->underflow[i] = 0xFFFFFFFF; |
| 1731 | } |
| 1732 | |
| 1733 | duprintf("translate_compat_table: size %u\n", info->size); |
| 1734 | j = 0; |
| 1735 | xt_compat_lock(AF_INET6); |
| 1736 | /* Walk through entries, checking offsets. */ |
| 1737 | xt_entry_foreach(iter0, entry0, total_size) { |
| 1738 | ret = check_compat_entry_size_and_hooks(iter0, info, &size, |
| 1739 | entry0, |
| 1740 | entry0 + total_size, |
| 1741 | hook_entries, |
| 1742 | underflows, |
| 1743 | name); |
| 1744 | if (ret != 0) |
| 1745 | goto out_unlock; |
| 1746 | ++j; |
| 1747 | } |
| 1748 | |
| 1749 | ret = -EINVAL; |
| 1750 | if (j != number) { |
| 1751 | duprintf("translate_compat_table: %u not %u entries\n", |
| 1752 | j, number); |
| 1753 | goto out_unlock; |
| 1754 | } |
| 1755 | |
| 1756 | /* Check hooks all assigned */ |
| 1757 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1758 | /* Only hooks which are valid */ |
| 1759 | if (!(valid_hooks & (1 << i))) |
| 1760 | continue; |
| 1761 | if (info->hook_entry[i] == 0xFFFFFFFF) { |
| 1762 | duprintf("Invalid hook entry %u %u\n", |
| 1763 | i, hook_entries[i]); |
| 1764 | goto out_unlock; |
| 1765 | } |
| 1766 | if (info->underflow[i] == 0xFFFFFFFF) { |
| 1767 | duprintf("Invalid underflow %u %u\n", |
| 1768 | i, underflows[i]); |
| 1769 | goto out_unlock; |
| 1770 | } |
| 1771 | } |
| 1772 | |
| 1773 | ret = -ENOMEM; |
| 1774 | newinfo = xt_alloc_table_info(size); |
| 1775 | if (!newinfo) |
| 1776 | goto out_unlock; |
| 1777 | |
| 1778 | newinfo->number = number; |
| 1779 | for (i = 0; i < NF_INET_NUMHOOKS; i++) { |
| 1780 | newinfo->hook_entry[i] = info->hook_entry[i]; |
| 1781 | newinfo->underflow[i] = info->underflow[i]; |
| 1782 | } |
| 1783 | entry1 = newinfo->entries[raw_smp_processor_id()]; |
| 1784 | pos = entry1; |
| 1785 | size = total_size; |
| 1786 | xt_entry_foreach(iter0, entry0, total_size) { |
| 1787 | ret = compat_copy_entry_from_user(iter0, &pos, &size, |
| 1788 | name, newinfo, entry1); |
| 1789 | if (ret != 0) |
| 1790 | break; |
| 1791 | } |
| 1792 | xt_compat_flush_offsets(AF_INET6); |
| 1793 | xt_compat_unlock(AF_INET6); |
| 1794 | if (ret) |
| 1795 | goto free_newinfo; |
| 1796 | |
| 1797 | ret = -ELOOP; |
| 1798 | if (!mark_source_chains(newinfo, valid_hooks, entry1)) |
| 1799 | goto free_newinfo; |
| 1800 | |
| 1801 | i = 0; |
| 1802 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
| 1803 | ret = compat_check_entry(iter1, net, name); |
| 1804 | if (ret != 0) |
| 1805 | break; |
| 1806 | ++i; |
| 1807 | } |
| 1808 | if (ret) { |
| 1809 | /* |
| 1810 | * The first i matches need cleanup_entry (calls ->destroy) |
| 1811 | * because they had called ->check already. The other j-i |
| 1812 | * entries need only release. |
| 1813 | */ |
| 1814 | int skip = i; |
| 1815 | j -= i; |
| 1816 | xt_entry_foreach(iter0, entry0, newinfo->size) { |
| 1817 | if (skip-- > 0) |
| 1818 | continue; |
| 1819 | if (j-- == 0) |
| 1820 | break; |
| 1821 | compat_release_entry(iter0); |
| 1822 | } |
| 1823 | xt_entry_foreach(iter1, entry1, newinfo->size) { |
| 1824 | if (i-- == 0) |
| 1825 | break; |
| 1826 | cleanup_entry(iter1, net); |
| 1827 | } |
| 1828 | xt_free_table_info(newinfo); |
| 1829 | return ret; |
| 1830 | } |
| 1831 | |
| 1832 | /* And one copy for every other CPU */ |
| 1833 | for_each_possible_cpu(i) |
| 1834 | if (newinfo->entries[i] && newinfo->entries[i] != entry1) |
| 1835 | memcpy(newinfo->entries[i], entry1, newinfo->size); |
| 1836 | |
| 1837 | *pinfo = newinfo; |
| 1838 | *pentry0 = entry1; |
| 1839 | xt_free_table_info(info); |
| 1840 | return 0; |
| 1841 | |
| 1842 | free_newinfo: |
| 1843 | xt_free_table_info(newinfo); |
| 1844 | out: |
| 1845 | xt_entry_foreach(iter0, entry0, total_size) { |
| 1846 | if (j-- == 0) |
| 1847 | break; |
| 1848 | compat_release_entry(iter0); |
| 1849 | } |
| 1850 | return ret; |
| 1851 | out_unlock: |
| 1852 | xt_compat_flush_offsets(AF_INET6); |
| 1853 | xt_compat_unlock(AF_INET6); |
| 1854 | goto out; |
| 1855 | } |
| 1856 | |
| 1857 | static int |
| 1858 | compat_do_replace(struct net *net, void __user *user, unsigned int len) |
| 1859 | { |
| 1860 | int ret; |
| 1861 | struct compat_ip6t_replace tmp; |
| 1862 | struct xt_table_info *newinfo; |
| 1863 | void *loc_cpu_entry; |
| 1864 | struct ip6t_entry *iter; |
| 1865 | |
| 1866 | if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| 1867 | return -EFAULT; |
| 1868 | |
| 1869 | /* overflow check */ |
| 1870 | if (tmp.size >= INT_MAX / num_possible_cpus()) |
| 1871 | return -ENOMEM; |
| 1872 | if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) |
| 1873 | return -ENOMEM; |
| 1874 | |
| 1875 | newinfo = xt_alloc_table_info(tmp.size); |
| 1876 | if (!newinfo) |
| 1877 | return -ENOMEM; |
| 1878 | |
| 1879 | /* choose the copy that is on our node/cpu */ |
| 1880 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; |
| 1881 | if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
| 1882 | tmp.size) != 0) { |
| 1883 | ret = -EFAULT; |
| 1884 | goto free_newinfo; |
| 1885 | } |
| 1886 | |
| 1887 | ret = translate_compat_table(net, tmp.name, tmp.valid_hooks, |
| 1888 | &newinfo, &loc_cpu_entry, tmp.size, |
| 1889 | tmp.num_entries, tmp.hook_entry, |
| 1890 | tmp.underflow); |
| 1891 | if (ret != 0) |
| 1892 | goto free_newinfo; |
| 1893 | |
| 1894 | duprintf("compat_do_replace: Translated table\n"); |
| 1895 | |
| 1896 | ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, |
| 1897 | tmp.num_counters, compat_ptr(tmp.counters)); |
| 1898 | if (ret) |
| 1899 | goto free_newinfo_untrans; |
| 1900 | return 0; |
| 1901 | |
| 1902 | free_newinfo_untrans: |
| 1903 | xt_entry_foreach(iter, loc_cpu_entry, newinfo->size) |
| 1904 | cleanup_entry(iter, net); |
| 1905 | free_newinfo: |
| 1906 | xt_free_table_info(newinfo); |
| 1907 | return ret; |
| 1908 | } |
| 1909 | |
| 1910 | static int |
| 1911 | compat_do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, |
| 1912 | unsigned int len) |
| 1913 | { |
| 1914 | int ret; |
| 1915 | |
| 1916 | if (!capable(CAP_NET_ADMIN)) |
| 1917 | return -EPERM; |
| 1918 | |
| 1919 | switch (cmd) { |
| 1920 | case IP6T_SO_SET_REPLACE: |
| 1921 | ret = compat_do_replace(sock_net(sk), user, len); |
| 1922 | break; |
| 1923 | |
| 1924 | case IP6T_SO_SET_ADD_COUNTERS: |
| 1925 | ret = do_add_counters(sock_net(sk), user, len, 1); |
| 1926 | break; |
| 1927 | |
| 1928 | default: |
| 1929 | duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); |
| 1930 | ret = -EINVAL; |
| 1931 | } |
| 1932 | |
| 1933 | return ret; |
| 1934 | } |
| 1935 | |
| 1936 | struct compat_ip6t_get_entries { |
| 1937 | char name[IP6T_TABLE_MAXNAMELEN]; |
| 1938 | compat_uint_t size; |
| 1939 | struct compat_ip6t_entry entrytable[0]; |
| 1940 | }; |
| 1941 | |
| 1942 | static int |
| 1943 | compat_copy_entries_to_user(unsigned int total_size, struct xt_table *table, |
| 1944 | void __user *userptr) |
| 1945 | { |
| 1946 | struct xt_counters *counters; |
| 1947 | const struct xt_table_info *private = table->private; |
| 1948 | void __user *pos; |
| 1949 | unsigned int size; |
| 1950 | int ret = 0; |
| 1951 | const void *loc_cpu_entry; |
| 1952 | unsigned int i = 0; |
| 1953 | struct ip6t_entry *iter; |
| 1954 | |
| 1955 | counters = alloc_counters(table); |
| 1956 | if (IS_ERR(counters)) |
| 1957 | return PTR_ERR(counters); |
| 1958 | |
| 1959 | /* choose the copy that is on our node/cpu, ... |
| 1960 | * This choice is lazy (because current thread is |
| 1961 | * allowed to migrate to another cpu) |
| 1962 | */ |
| 1963 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
| 1964 | pos = userptr; |
| 1965 | size = total_size; |
| 1966 | xt_entry_foreach(iter, loc_cpu_entry, total_size) { |
| 1967 | ret = compat_copy_entry_to_user(iter, &pos, |
| 1968 | &size, counters, i++); |
| 1969 | if (ret != 0) |
| 1970 | break; |
| 1971 | } |
| 1972 | |
| 1973 | vfree(counters); |
| 1974 | return ret; |
| 1975 | } |
| 1976 | |
| 1977 | static int |
| 1978 | compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr, |
| 1979 | int *len) |
| 1980 | { |
| 1981 | int ret; |
| 1982 | struct compat_ip6t_get_entries get; |
| 1983 | struct xt_table *t; |
| 1984 | |
| 1985 | if (*len < sizeof(get)) { |
| 1986 | duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get)); |
| 1987 | return -EINVAL; |
| 1988 | } |
| 1989 | |
| 1990 | if (copy_from_user(&get, uptr, sizeof(get)) != 0) |
| 1991 | return -EFAULT; |
| 1992 | |
| 1993 | if (*len != sizeof(struct compat_ip6t_get_entries) + get.size) { |
| 1994 | duprintf("compat_get_entries: %u != %zu\n", |
| 1995 | *len, sizeof(get) + get.size); |
| 1996 | return -EINVAL; |
| 1997 | } |
| 1998 | |
| 1999 | xt_compat_lock(AF_INET6); |
| 2000 | t = xt_find_table_lock(net, AF_INET6, get.name); |
| 2001 | if (t && !IS_ERR(t)) { |
| 2002 | const struct xt_table_info *private = t->private; |
| 2003 | struct xt_table_info info; |
| 2004 | duprintf("t->private->number = %u\n", private->number); |
| 2005 | ret = compat_table_info(private, &info); |
| 2006 | if (!ret && get.size == info.size) { |
| 2007 | ret = compat_copy_entries_to_user(private->size, |
| 2008 | t, uptr->entrytable); |
| 2009 | } else if (!ret) { |
| 2010 | duprintf("compat_get_entries: I've got %u not %u!\n", |
| 2011 | private->size, get.size); |
| 2012 | ret = -EAGAIN; |
| 2013 | } |
| 2014 | xt_compat_flush_offsets(AF_INET6); |
| 2015 | module_put(t->me); |
| 2016 | xt_table_unlock(t); |
| 2017 | } else |
| 2018 | ret = t ? PTR_ERR(t) : -ENOENT; |
| 2019 | |
| 2020 | xt_compat_unlock(AF_INET6); |
| 2021 | return ret; |
| 2022 | } |
| 2023 | |
| 2024 | static int do_ip6t_get_ctl(struct sock *, int, void __user *, int *); |
| 2025 | |
| 2026 | static int |
| 2027 | compat_do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| 2028 | { |
| 2029 | int ret; |
| 2030 | |
| 2031 | if (!capable(CAP_NET_ADMIN)) |
| 2032 | return -EPERM; |
| 2033 | |
| 2034 | switch (cmd) { |
| 2035 | case IP6T_SO_GET_INFO: |
| 2036 | ret = get_info(sock_net(sk), user, len, 1); |
| 2037 | break; |
| 2038 | case IP6T_SO_GET_ENTRIES: |
| 2039 | ret = compat_get_entries(sock_net(sk), user, len); |
| 2040 | break; |
| 2041 | default: |
| 2042 | ret = do_ip6t_get_ctl(sk, cmd, user, len); |
| 2043 | } |
| 2044 | return ret; |
| 2045 | } |
| 2046 | #endif |
| 2047 | |
| 2048 | static int |
| 2049 | do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
| 2050 | { |
| 2051 | int ret; |
| 2052 | |
| 2053 | if (!capable(CAP_NET_ADMIN)) |
| 2054 | return -EPERM; |
| 2055 | |
| 2056 | switch (cmd) { |
| 2057 | case IP6T_SO_SET_REPLACE: |
| 2058 | ret = do_replace(sock_net(sk), user, len); |
| 2059 | break; |
| 2060 | |
| 2061 | case IP6T_SO_SET_ADD_COUNTERS: |
| 2062 | ret = do_add_counters(sock_net(sk), user, len, 0); |
| 2063 | break; |
| 2064 | |
| 2065 | default: |
| 2066 | duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); |
| 2067 | ret = -EINVAL; |
| 2068 | } |
| 2069 | |
| 2070 | return ret; |
| 2071 | } |
| 2072 | |
| 2073 | static int |
| 2074 | do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| 2075 | { |
| 2076 | int ret; |
| 2077 | |
| 2078 | if (!capable(CAP_NET_ADMIN)) |
| 2079 | return -EPERM; |
| 2080 | |
| 2081 | switch (cmd) { |
| 2082 | case IP6T_SO_GET_INFO: |
| 2083 | ret = get_info(sock_net(sk), user, len, 0); |
| 2084 | break; |
| 2085 | |
| 2086 | case IP6T_SO_GET_ENTRIES: |
| 2087 | ret = get_entries(sock_net(sk), user, len); |
| 2088 | break; |
| 2089 | |
| 2090 | case IP6T_SO_GET_REVISION_MATCH: |
| 2091 | case IP6T_SO_GET_REVISION_TARGET: { |
| 2092 | struct ip6t_get_revision rev; |
| 2093 | int target; |
| 2094 | |
| 2095 | if (*len != sizeof(rev)) { |
| 2096 | ret = -EINVAL; |
| 2097 | break; |
| 2098 | } |
| 2099 | if (copy_from_user(&rev, user, sizeof(rev)) != 0) { |
| 2100 | ret = -EFAULT; |
| 2101 | break; |
| 2102 | } |
| 2103 | |
| 2104 | if (cmd == IP6T_SO_GET_REVISION_TARGET) |
| 2105 | target = 1; |
| 2106 | else |
| 2107 | target = 0; |
| 2108 | |
| 2109 | try_then_request_module(xt_find_revision(AF_INET6, rev.name, |
| 2110 | rev.revision, |
| 2111 | target, &ret), |
| 2112 | "ip6t_%s", rev.name); |
| 2113 | break; |
| 2114 | } |
| 2115 | |
| 2116 | default: |
| 2117 | duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); |
| 2118 | ret = -EINVAL; |
| 2119 | } |
| 2120 | |
| 2121 | return ret; |
| 2122 | } |
| 2123 | |
| 2124 | struct xt_table *ip6t_register_table(struct net *net, |
| 2125 | const struct xt_table *table, |
| 2126 | const struct ip6t_replace *repl) |
| 2127 | { |
| 2128 | int ret; |
| 2129 | struct xt_table_info *newinfo; |
| 2130 | struct xt_table_info bootstrap |
| 2131 | = { 0, 0, 0, { 0 }, { 0 }, { } }; |
| 2132 | void *loc_cpu_entry; |
| 2133 | struct xt_table *new_table; |
| 2134 | |
| 2135 | newinfo = xt_alloc_table_info(repl->size); |
| 2136 | if (!newinfo) { |
| 2137 | ret = -ENOMEM; |
| 2138 | goto out; |
| 2139 | } |
| 2140 | |
| 2141 | /* choose the copy on our node/cpu, but dont care about preemption */ |
| 2142 | loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; |
| 2143 | memcpy(loc_cpu_entry, repl->entries, repl->size); |
| 2144 | |
| 2145 | ret = translate_table(net, newinfo, loc_cpu_entry, repl); |
| 2146 | if (ret != 0) |
| 2147 | goto out_free; |
| 2148 | |
| 2149 | new_table = xt_register_table(net, table, &bootstrap, newinfo); |
| 2150 | if (IS_ERR(new_table)) { |
| 2151 | ret = PTR_ERR(new_table); |
| 2152 | goto out_free; |
| 2153 | } |
| 2154 | return new_table; |
| 2155 | |
| 2156 | out_free: |
| 2157 | xt_free_table_info(newinfo); |
| 2158 | out: |
| 2159 | return ERR_PTR(ret); |
| 2160 | } |
| 2161 | |
| 2162 | void ip6t_unregister_table(struct net *net, struct xt_table *table) |
| 2163 | { |
| 2164 | struct xt_table_info *private; |
| 2165 | void *loc_cpu_entry; |
| 2166 | struct module *table_owner = table->me; |
| 2167 | struct ip6t_entry *iter; |
| 2168 | |
| 2169 | private = xt_unregister_table(table); |
| 2170 | |
| 2171 | /* Decrease module usage counts and free resources */ |
| 2172 | loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
| 2173 | xt_entry_foreach(iter, loc_cpu_entry, private->size) |
| 2174 | cleanup_entry(iter, net); |
| 2175 | if (private->number > private->initial_entries) |
| 2176 | module_put(table_owner); |
| 2177 | xt_free_table_info(private); |
| 2178 | } |
| 2179 | |
| 2180 | /* Returns 1 if the type and code is matched by the range, 0 otherwise */ |
| 2181 | static inline bool |
| 2182 | icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, |
| 2183 | u_int8_t type, u_int8_t code, |
| 2184 | bool invert) |
| 2185 | { |
| 2186 | return (type == test_type && code >= min_code && code <= max_code) |
| 2187 | ^ invert; |
| 2188 | } |
| 2189 | |
| 2190 | static bool |
| 2191 | icmp6_match(const struct sk_buff *skb, const struct xt_match_param *par) |
| 2192 | { |
| 2193 | const struct icmp6hdr *ic; |
| 2194 | struct icmp6hdr _icmph; |
| 2195 | const struct ip6t_icmp *icmpinfo = par->matchinfo; |
| 2196 | |
| 2197 | /* Must not be a fragment. */ |
| 2198 | if (par->fragoff != 0) |
| 2199 | return false; |
| 2200 | |
| 2201 | ic = skb_header_pointer(skb, par->thoff, sizeof(_icmph), &_icmph); |
| 2202 | if (ic == NULL) { |
| 2203 | /* We've been asked to examine this packet, and we |
| 2204 | * can't. Hence, no choice but to drop. |
| 2205 | */ |
| 2206 | duprintf("Dropping evil ICMP tinygram.\n"); |
| 2207 | *par->hotdrop = true; |
| 2208 | return false; |
| 2209 | } |
| 2210 | |
| 2211 | return icmp6_type_code_match(icmpinfo->type, |
| 2212 | icmpinfo->code[0], |
| 2213 | icmpinfo->code[1], |
| 2214 | ic->icmp6_type, ic->icmp6_code, |
| 2215 | !!(icmpinfo->invflags&IP6T_ICMP_INV)); |
| 2216 | } |
| 2217 | |
| 2218 | /* Called when user tries to insert an entry of this type. */ |
| 2219 | static bool icmp6_checkentry(const struct xt_mtchk_param *par) |
| 2220 | { |
| 2221 | const struct ip6t_icmp *icmpinfo = par->matchinfo; |
| 2222 | |
| 2223 | /* Must specify no unknown invflags */ |
| 2224 | return !(icmpinfo->invflags & ~IP6T_ICMP_INV); |
| 2225 | } |
| 2226 | |
| 2227 | /* The built-in targets: standard (NULL) and error. */ |
| 2228 | static struct xt_target ip6t_standard_target __read_mostly = { |
| 2229 | .name = IP6T_STANDARD_TARGET, |
| 2230 | .targetsize = sizeof(int), |
| 2231 | .family = NFPROTO_IPV6, |
| 2232 | #ifdef CONFIG_COMPAT |
| 2233 | .compatsize = sizeof(compat_int_t), |
| 2234 | .compat_from_user = compat_standard_from_user, |
| 2235 | .compat_to_user = compat_standard_to_user, |
| 2236 | #endif |
| 2237 | }; |
| 2238 | |
| 2239 | static struct xt_target ip6t_error_target __read_mostly = { |
| 2240 | .name = IP6T_ERROR_TARGET, |
| 2241 | .target = ip6t_error, |
| 2242 | .targetsize = IP6T_FUNCTION_MAXNAMELEN, |
| 2243 | .family = NFPROTO_IPV6, |
| 2244 | }; |
| 2245 | |
| 2246 | static struct nf_sockopt_ops ip6t_sockopts = { |
| 2247 | .pf = PF_INET6, |
| 2248 | .set_optmin = IP6T_BASE_CTL, |
| 2249 | .set_optmax = IP6T_SO_SET_MAX+1, |
| 2250 | .set = do_ip6t_set_ctl, |
| 2251 | #ifdef CONFIG_COMPAT |
| 2252 | .compat_set = compat_do_ip6t_set_ctl, |
| 2253 | #endif |
| 2254 | .get_optmin = IP6T_BASE_CTL, |
| 2255 | .get_optmax = IP6T_SO_GET_MAX+1, |
| 2256 | .get = do_ip6t_get_ctl, |
| 2257 | #ifdef CONFIG_COMPAT |
| 2258 | .compat_get = compat_do_ip6t_get_ctl, |
| 2259 | #endif |
| 2260 | .owner = THIS_MODULE, |
| 2261 | }; |
| 2262 | |
| 2263 | static struct xt_match icmp6_matchstruct __read_mostly = { |
| 2264 | .name = "icmp6", |
| 2265 | .match = icmp6_match, |
| 2266 | .matchsize = sizeof(struct ip6t_icmp), |
| 2267 | .checkentry = icmp6_checkentry, |
| 2268 | .proto = IPPROTO_ICMPV6, |
| 2269 | .family = NFPROTO_IPV6, |
| 2270 | }; |
| 2271 | |
| 2272 | static int __net_init ip6_tables_net_init(struct net *net) |
| 2273 | { |
| 2274 | return xt_proto_init(net, NFPROTO_IPV6); |
| 2275 | } |
| 2276 | |
| 2277 | static void __net_exit ip6_tables_net_exit(struct net *net) |
| 2278 | { |
| 2279 | xt_proto_fini(net, NFPROTO_IPV6); |
| 2280 | } |
| 2281 | |
| 2282 | static struct pernet_operations ip6_tables_net_ops = { |
| 2283 | .init = ip6_tables_net_init, |
| 2284 | .exit = ip6_tables_net_exit, |
| 2285 | }; |
| 2286 | |
| 2287 | static int __init ip6_tables_init(void) |
| 2288 | { |
| 2289 | int ret; |
| 2290 | |
| 2291 | ret = register_pernet_subsys(&ip6_tables_net_ops); |
| 2292 | if (ret < 0) |
| 2293 | goto err1; |
| 2294 | |
| 2295 | /* Noone else will be downing sem now, so we won't sleep */ |
| 2296 | ret = xt_register_target(&ip6t_standard_target); |
| 2297 | if (ret < 0) |
| 2298 | goto err2; |
| 2299 | ret = xt_register_target(&ip6t_error_target); |
| 2300 | if (ret < 0) |
| 2301 | goto err3; |
| 2302 | ret = xt_register_match(&icmp6_matchstruct); |
| 2303 | if (ret < 0) |
| 2304 | goto err4; |
| 2305 | |
| 2306 | /* Register setsockopt */ |
| 2307 | ret = nf_register_sockopt(&ip6t_sockopts); |
| 2308 | if (ret < 0) |
| 2309 | goto err5; |
| 2310 | |
| 2311 | printk(KERN_INFO "ip6_tables: (C) 2000-2006 Netfilter Core Team\n"); |
| 2312 | return 0; |
| 2313 | |
| 2314 | err5: |
| 2315 | xt_unregister_match(&icmp6_matchstruct); |
| 2316 | err4: |
| 2317 | xt_unregister_target(&ip6t_error_target); |
| 2318 | err3: |
| 2319 | xt_unregister_target(&ip6t_standard_target); |
| 2320 | err2: |
| 2321 | unregister_pernet_subsys(&ip6_tables_net_ops); |
| 2322 | err1: |
| 2323 | return ret; |
| 2324 | } |
| 2325 | |
| 2326 | static void __exit ip6_tables_fini(void) |
| 2327 | { |
| 2328 | nf_unregister_sockopt(&ip6t_sockopts); |
| 2329 | |
| 2330 | xt_unregister_match(&icmp6_matchstruct); |
| 2331 | xt_unregister_target(&ip6t_error_target); |
| 2332 | xt_unregister_target(&ip6t_standard_target); |
| 2333 | |
| 2334 | unregister_pernet_subsys(&ip6_tables_net_ops); |
| 2335 | } |
| 2336 | |
| 2337 | /* |
| 2338 | * find the offset to specified header or the protocol number of last header |
| 2339 | * if target < 0. "last header" is transport protocol header, ESP, or |
| 2340 | * "No next header". |
| 2341 | * |
| 2342 | * If target header is found, its offset is set in *offset and return protocol |
| 2343 | * number. Otherwise, return -1. |
| 2344 | * |
| 2345 | * If the first fragment doesn't contain the final protocol header or |
| 2346 | * NEXTHDR_NONE it is considered invalid. |
| 2347 | * |
| 2348 | * Note that non-1st fragment is special case that "the protocol number |
| 2349 | * of last header" is "next header" field in Fragment header. In this case, |
| 2350 | * *offset is meaningless and fragment offset is stored in *fragoff if fragoff |
| 2351 | * isn't NULL. |
| 2352 | * |
| 2353 | */ |
| 2354 | int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, |
| 2355 | int target, unsigned short *fragoff) |
| 2356 | { |
| 2357 | unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr); |
| 2358 | u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
| 2359 | unsigned int len = skb->len - start; |
| 2360 | |
| 2361 | if (fragoff) |
| 2362 | *fragoff = 0; |
| 2363 | |
| 2364 | while (nexthdr != target) { |
| 2365 | struct ipv6_opt_hdr _hdr, *hp; |
| 2366 | unsigned int hdrlen; |
| 2367 | |
| 2368 | if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) { |
| 2369 | if (target < 0) |
| 2370 | break; |
| 2371 | return -ENOENT; |
| 2372 | } |
| 2373 | |
| 2374 | hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); |
| 2375 | if (hp == NULL) |
| 2376 | return -EBADMSG; |
| 2377 | if (nexthdr == NEXTHDR_FRAGMENT) { |
| 2378 | unsigned short _frag_off; |
| 2379 | __be16 *fp; |
| 2380 | fp = skb_header_pointer(skb, |
| 2381 | start+offsetof(struct frag_hdr, |
| 2382 | frag_off), |
| 2383 | sizeof(_frag_off), |
| 2384 | &_frag_off); |
| 2385 | if (fp == NULL) |
| 2386 | return -EBADMSG; |
| 2387 | |
| 2388 | _frag_off = ntohs(*fp) & ~0x7; |
| 2389 | if (_frag_off) { |
| 2390 | if (target < 0 && |
| 2391 | ((!ipv6_ext_hdr(hp->nexthdr)) || |
| 2392 | hp->nexthdr == NEXTHDR_NONE)) { |
| 2393 | if (fragoff) |
| 2394 | *fragoff = _frag_off; |
| 2395 | return hp->nexthdr; |
| 2396 | } |
| 2397 | return -ENOENT; |
| 2398 | } |
| 2399 | hdrlen = 8; |
| 2400 | } else if (nexthdr == NEXTHDR_AUTH) |
| 2401 | hdrlen = (hp->hdrlen + 2) << 2; |
| 2402 | else |
| 2403 | hdrlen = ipv6_optlen(hp); |
| 2404 | |
| 2405 | nexthdr = hp->nexthdr; |
| 2406 | len -= hdrlen; |
| 2407 | start += hdrlen; |
| 2408 | } |
| 2409 | |
| 2410 | *offset = start; |
| 2411 | return nexthdr; |
| 2412 | } |
| 2413 | |
| 2414 | EXPORT_SYMBOL(ip6t_register_table); |
| 2415 | EXPORT_SYMBOL(ip6t_unregister_table); |
| 2416 | EXPORT_SYMBOL(ip6t_do_table); |
| 2417 | EXPORT_SYMBOL(ip6t_ext_hdr); |
| 2418 | EXPORT_SYMBOL(ipv6_find_hdr); |
| 2419 | |
| 2420 | module_init(ip6_tables_init); |
| 2421 | module_exit(ip6_tables_fini); |