| /* |
| * Packet matching code. |
| * |
| * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
| * Copyright (C) 2000-2005 Netfilter Core Team <coreteam@netfilter.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/capability.h> |
| #include <linux/in.h> |
| #include <linux/skbuff.h> |
| #include <linux/kmod.h> |
| #include <linux/vmalloc.h> |
| #include <linux/netdevice.h> |
| #include <linux/module.h> |
| #include <linux/poison.h> |
| #include <linux/icmpv6.h> |
| #include <net/ipv6.h> |
| #include <asm/uaccess.h> |
| #include <linux/mutex.h> |
| #include <linux/proc_fs.h> |
| #include <linux/cpumask.h> |
| |
| #include <linux/netfilter_ipv6/ip6_tables.h> |
| #include <linux/netfilter/x_tables.h> |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); |
| MODULE_DESCRIPTION("IPv6 packet filter"); |
| |
| #define IPV6_HDR_LEN (sizeof(struct ipv6hdr)) |
| #define IPV6_OPTHDR_LEN (sizeof(struct ipv6_opt_hdr)) |
| |
| /*#define DEBUG_IP_FIREWALL*/ |
| /*#define DEBUG_ALLOW_ALL*/ /* Useful for remote debugging */ |
| /*#define DEBUG_IP_FIREWALL_USER*/ |
| |
| #ifdef DEBUG_IP_FIREWALL |
| #define dprintf(format, args...) printk(format , ## args) |
| #else |
| #define dprintf(format, args...) |
| #endif |
| |
| #ifdef DEBUG_IP_FIREWALL_USER |
| #define duprintf(format, args...) printk(format , ## args) |
| #else |
| #define duprintf(format, args...) |
| #endif |
| |
| #ifdef CONFIG_NETFILTER_DEBUG |
| #define IP_NF_ASSERT(x) \ |
| do { \ |
| if (!(x)) \ |
| printk("IP_NF_ASSERT: %s:%s:%u\n", \ |
| __FUNCTION__, __FILE__, __LINE__); \ |
| } while(0) |
| #else |
| #define IP_NF_ASSERT(x) |
| #endif |
| |
| #if 0 |
| /* All the better to debug you with... */ |
| #define static |
| #define inline |
| #endif |
| |
| /* |
| We keep a set of rules for each CPU, so we can avoid write-locking |
| them in the softirq when updating the counters and therefore |
| only need to read-lock in the softirq; doing a write_lock_bh() in user |
| context stops packets coming through and allows user context to read |
| the counters or update the rules. |
| |
| Hence the start of any table is given by get_table() below. */ |
| |
| #if 0 |
| #define down(x) do { printk("DOWN:%u:" #x "\n", __LINE__); down(x); } while(0) |
| #define down_interruptible(x) ({ int __r; printk("DOWNi:%u:" #x "\n", __LINE__); __r = down_interruptible(x); if (__r != 0) printk("ABORT-DOWNi:%u\n", __LINE__); __r; }) |
| #define up(x) do { printk("UP:%u:" #x "\n", __LINE__); up(x); } while(0) |
| #endif |
| |
| /* Check for an extension */ |
| int |
| ip6t_ext_hdr(u8 nexthdr) |
| { |
| return ( (nexthdr == IPPROTO_HOPOPTS) || |
| (nexthdr == IPPROTO_ROUTING) || |
| (nexthdr == IPPROTO_FRAGMENT) || |
| (nexthdr == IPPROTO_ESP) || |
| (nexthdr == IPPROTO_AH) || |
| (nexthdr == IPPROTO_NONE) || |
| (nexthdr == IPPROTO_DSTOPTS) ); |
| } |
| |
| /* Returns whether matches rule or not. */ |
| static inline bool |
| ip6_packet_match(const struct sk_buff *skb, |
| const char *indev, |
| const char *outdev, |
| const struct ip6t_ip6 *ip6info, |
| unsigned int *protoff, |
| int *fragoff, bool *hotdrop) |
| { |
| size_t i; |
| unsigned long ret; |
| const struct ipv6hdr *ipv6 = ipv6_hdr(skb); |
| |
| #define FWINV(bool,invflg) ((bool) ^ !!(ip6info->invflags & invflg)) |
| |
| if (FWINV(ipv6_masked_addr_cmp(&ipv6->saddr, &ip6info->smsk, |
| &ip6info->src), IP6T_INV_SRCIP) |
| || FWINV(ipv6_masked_addr_cmp(&ipv6->daddr, &ip6info->dmsk, |
| &ip6info->dst), IP6T_INV_DSTIP)) { |
| dprintf("Source or dest mismatch.\n"); |
| /* |
| dprintf("SRC: %u. Mask: %u. Target: %u.%s\n", ip->saddr, |
| ipinfo->smsk.s_addr, ipinfo->src.s_addr, |
| ipinfo->invflags & IP6T_INV_SRCIP ? " (INV)" : ""); |
| dprintf("DST: %u. Mask: %u. Target: %u.%s\n", ip->daddr, |
| ipinfo->dmsk.s_addr, ipinfo->dst.s_addr, |
| ipinfo->invflags & IP6T_INV_DSTIP ? " (INV)" : "");*/ |
| return false; |
| } |
| |
| /* Look for ifname matches; this should unroll nicely. */ |
| for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { |
| ret |= (((const unsigned long *)indev)[i] |
| ^ ((const unsigned long *)ip6info->iniface)[i]) |
| & ((const unsigned long *)ip6info->iniface_mask)[i]; |
| } |
| |
| if (FWINV(ret != 0, IP6T_INV_VIA_IN)) { |
| dprintf("VIA in mismatch (%s vs %s).%s\n", |
| indev, ip6info->iniface, |
| ip6info->invflags&IP6T_INV_VIA_IN ?" (INV)":""); |
| return false; |
| } |
| |
| for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) { |
| ret |= (((const unsigned long *)outdev)[i] |
| ^ ((const unsigned long *)ip6info->outiface)[i]) |
| & ((const unsigned long *)ip6info->outiface_mask)[i]; |
| } |
| |
| if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) { |
| dprintf("VIA out mismatch (%s vs %s).%s\n", |
| outdev, ip6info->outiface, |
| ip6info->invflags&IP6T_INV_VIA_OUT ?" (INV)":""); |
| return false; |
| } |
| |
| /* ... might want to do something with class and flowlabel here ... */ |
| |
| /* look for the desired protocol header */ |
| if((ip6info->flags & IP6T_F_PROTO)) { |
| int protohdr; |
| unsigned short _frag_off; |
| |
| protohdr = ipv6_find_hdr(skb, protoff, -1, &_frag_off); |
| if (protohdr < 0) { |
| if (_frag_off == 0) |
| *hotdrop = true; |
| return false; |
| } |
| *fragoff = _frag_off; |
| |
| dprintf("Packet protocol %hi ?= %s%hi.\n", |
| protohdr, |
| ip6info->invflags & IP6T_INV_PROTO ? "!":"", |
| ip6info->proto); |
| |
| if (ip6info->proto == protohdr) { |
| if(ip6info->invflags & IP6T_INV_PROTO) { |
| return false; |
| } |
| return true; |
| } |
| |
| /* We need match for the '-p all', too! */ |
| if ((ip6info->proto != 0) && |
| !(ip6info->invflags & IP6T_INV_PROTO)) |
| return false; |
| } |
| return true; |
| } |
| |
| /* should be ip6 safe */ |
| static inline int |
| ip6_checkentry(const struct ip6t_ip6 *ipv6) |
| { |
| if (ipv6->flags & ~IP6T_F_MASK) { |
| duprintf("Unknown flag bits set: %08X\n", |
| ipv6->flags & ~IP6T_F_MASK); |
| return 0; |
| } |
| if (ipv6->invflags & ~IP6T_INV_MASK) { |
| duprintf("Unknown invflag bits set: %08X\n", |
| ipv6->invflags & ~IP6T_INV_MASK); |
| return 0; |
| } |
| return 1; |
| } |
| |
| static unsigned int |
| ip6t_error(struct sk_buff **pskb, |
| const struct net_device *in, |
| const struct net_device *out, |
| unsigned int hooknum, |
| const struct xt_target *target, |
| const void *targinfo) |
| { |
| if (net_ratelimit()) |
| printk("ip6_tables: error: `%s'\n", (char *)targinfo); |
| |
| return NF_DROP; |
| } |
| |
| static inline |
| bool do_match(struct ip6t_entry_match *m, |
| const struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| int offset, |
| unsigned int protoff, |
| bool *hotdrop) |
| { |
| /* Stop iteration if it doesn't match */ |
| if (!m->u.kernel.match->match(skb, in, out, m->u.kernel.match, m->data, |
| offset, protoff, hotdrop)) |
| return true; |
| else |
| return false; |
| } |
| |
| static inline struct ip6t_entry * |
| get_entry(void *base, unsigned int offset) |
| { |
| return (struct ip6t_entry *)(base + offset); |
| } |
| |
| /* Returns one of the generic firewall policies, like NF_ACCEPT. */ |
| unsigned int |
| ip6t_do_table(struct sk_buff **pskb, |
| unsigned int hook, |
| const struct net_device *in, |
| const struct net_device *out, |
| struct xt_table *table) |
| { |
| static const char nulldevname[IFNAMSIZ] __attribute__((aligned(sizeof(long)))); |
| int offset = 0; |
| unsigned int protoff = 0; |
| bool hotdrop = false; |
| /* Initializing verdict to NF_DROP keeps gcc happy. */ |
| unsigned int verdict = NF_DROP; |
| const char *indev, *outdev; |
| void *table_base; |
| struct ip6t_entry *e, *back; |
| struct xt_table_info *private; |
| |
| /* Initialization */ |
| indev = in ? in->name : nulldevname; |
| outdev = out ? out->name : nulldevname; |
| /* We handle fragments by dealing with the first fragment as |
| * if it was a normal packet. All other fragments are treated |
| * normally, except that they will NEVER match rules that ask |
| * things we don't know, ie. tcp syn flag or ports). If the |
| * rule is also a fragment-specific rule, non-fragments won't |
| * match it. */ |
| |
| read_lock_bh(&table->lock); |
| private = table->private; |
| IP_NF_ASSERT(table->valid_hooks & (1 << hook)); |
| table_base = (void *)private->entries[smp_processor_id()]; |
| e = get_entry(table_base, private->hook_entry[hook]); |
| |
| /* For return from builtin chain */ |
| back = get_entry(table_base, private->underflow[hook]); |
| |
| do { |
| IP_NF_ASSERT(e); |
| IP_NF_ASSERT(back); |
| if (ip6_packet_match(*pskb, indev, outdev, &e->ipv6, |
| &protoff, &offset, &hotdrop)) { |
| struct ip6t_entry_target *t; |
| |
| if (IP6T_MATCH_ITERATE(e, do_match, |
| *pskb, in, out, |
| offset, protoff, &hotdrop) != 0) |
| goto no_match; |
| |
| ADD_COUNTER(e->counters, |
| ntohs(ipv6_hdr(*pskb)->payload_len) |
| + IPV6_HDR_LEN, |
| 1); |
| |
| t = ip6t_get_target(e); |
| IP_NF_ASSERT(t->u.kernel.target); |
| /* Standard target? */ |
| if (!t->u.kernel.target->target) { |
| int v; |
| |
| v = ((struct ip6t_standard_target *)t)->verdict; |
| if (v < 0) { |
| /* Pop from stack? */ |
| if (v != IP6T_RETURN) { |
| verdict = (unsigned)(-v) - 1; |
| break; |
| } |
| e = back; |
| back = get_entry(table_base, |
| back->comefrom); |
| continue; |
| } |
| if (table_base + v != (void *)e + e->next_offset |
| && !(e->ipv6.flags & IP6T_F_GOTO)) { |
| /* Save old back ptr in next entry */ |
| struct ip6t_entry *next |
| = (void *)e + e->next_offset; |
| next->comefrom |
| = (void *)back - table_base; |
| /* set back pointer to next entry */ |
| back = next; |
| } |
| |
| e = get_entry(table_base, v); |
| } else { |
| /* Targets which reenter must return |
| abs. verdicts */ |
| #ifdef CONFIG_NETFILTER_DEBUG |
| ((struct ip6t_entry *)table_base)->comefrom |
| = 0xeeeeeeec; |
| #endif |
| verdict = t->u.kernel.target->target(pskb, |
| in, out, |
| hook, |
| t->u.kernel.target, |
| t->data); |
| |
| #ifdef CONFIG_NETFILTER_DEBUG |
| if (((struct ip6t_entry *)table_base)->comefrom |
| != 0xeeeeeeec |
| && verdict == IP6T_CONTINUE) { |
| printk("Target %s reentered!\n", |
| t->u.kernel.target->name); |
| verdict = NF_DROP; |
| } |
| ((struct ip6t_entry *)table_base)->comefrom |
| = 0x57acc001; |
| #endif |
| if (verdict == IP6T_CONTINUE) |
| e = (void *)e + e->next_offset; |
| else |
| /* Verdict */ |
| break; |
| } |
| } else { |
| |
| no_match: |
| e = (void *)e + e->next_offset; |
| } |
| } while (!hotdrop); |
| |
| #ifdef CONFIG_NETFILTER_DEBUG |
| ((struct ip6t_entry *)table_base)->comefrom = NETFILTER_LINK_POISON; |
| #endif |
| read_unlock_bh(&table->lock); |
| |
| #ifdef DEBUG_ALLOW_ALL |
| return NF_ACCEPT; |
| #else |
| if (hotdrop) |
| return NF_DROP; |
| else return verdict; |
| #endif |
| } |
| |
| /* All zeroes == unconditional rule. */ |
| static inline int |
| unconditional(const struct ip6t_ip6 *ipv6) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < sizeof(*ipv6); i++) |
| if (((char *)ipv6)[i]) |
| break; |
| |
| return (i == sizeof(*ipv6)); |
| } |
| |
| /* Figures out from what hook each rule can be called: returns 0 if |
| there are loops. Puts hook bitmask in comefrom. */ |
| static int |
| mark_source_chains(struct xt_table_info *newinfo, |
| unsigned int valid_hooks, void *entry0) |
| { |
| unsigned int hook; |
| |
| /* No recursion; use packet counter to save back ptrs (reset |
| to 0 as we leave), and comefrom to save source hook bitmask */ |
| for (hook = 0; hook < NF_IP6_NUMHOOKS; hook++) { |
| unsigned int pos = newinfo->hook_entry[hook]; |
| struct ip6t_entry *e |
| = (struct ip6t_entry *)(entry0 + pos); |
| int visited = e->comefrom & (1 << hook); |
| |
| if (!(valid_hooks & (1 << hook))) |
| continue; |
| |
| /* Set initial back pointer. */ |
| e->counters.pcnt = pos; |
| |
| for (;;) { |
| struct ip6t_standard_target *t |
| = (void *)ip6t_get_target(e); |
| |
| if (e->comefrom & (1 << NF_IP6_NUMHOOKS)) { |
| printk("iptables: loop hook %u pos %u %08X.\n", |
| hook, pos, e->comefrom); |
| return 0; |
| } |
| e->comefrom |
| |= ((1 << hook) | (1 << NF_IP6_NUMHOOKS)); |
| |
| /* Unconditional return/END. */ |
| if ((e->target_offset == sizeof(struct ip6t_entry) |
| && (strcmp(t->target.u.user.name, |
| IP6T_STANDARD_TARGET) == 0) |
| && t->verdict < 0 |
| && unconditional(&e->ipv6)) || visited) { |
| unsigned int oldpos, size; |
| |
| if (t->verdict < -NF_MAX_VERDICT - 1) { |
| duprintf("mark_source_chains: bad " |
| "negative verdict (%i)\n", |
| t->verdict); |
| return 0; |
| } |
| |
| /* Return: backtrack through the last |
| big jump. */ |
| do { |
| e->comefrom ^= (1<<NF_IP6_NUMHOOKS); |
| #ifdef DEBUG_IP_FIREWALL_USER |
| if (e->comefrom |
| & (1 << NF_IP6_NUMHOOKS)) { |
| duprintf("Back unset " |
| "on hook %u " |
| "rule %u\n", |
| hook, pos); |
| } |
| #endif |
| oldpos = pos; |
| pos = e->counters.pcnt; |
| e->counters.pcnt = 0; |
| |
| /* We're at the start. */ |
| if (pos == oldpos) |
| goto next; |
| |
| e = (struct ip6t_entry *) |
| (entry0 + pos); |
| } while (oldpos == pos + e->next_offset); |
| |
| /* Move along one */ |
| size = e->next_offset; |
| e = (struct ip6t_entry *) |
| (entry0 + pos + size); |
| e->counters.pcnt = pos; |
| pos += size; |
| } else { |
| int newpos = t->verdict; |
| |
| if (strcmp(t->target.u.user.name, |
| IP6T_STANDARD_TARGET) == 0 |
| && newpos >= 0) { |
| if (newpos > newinfo->size - |
| sizeof(struct ip6t_entry)) { |
| duprintf("mark_source_chains: " |
| "bad verdict (%i)\n", |
| newpos); |
| return 0; |
| } |
| /* This a jump; chase it. */ |
| duprintf("Jump rule %u -> %u\n", |
| pos, newpos); |
| } else { |
| /* ... this is a fallthru */ |
| newpos = pos + e->next_offset; |
| } |
| e = (struct ip6t_entry *) |
| (entry0 + newpos); |
| e->counters.pcnt = pos; |
| pos = newpos; |
| } |
| } |
| next: |
| duprintf("Finished chain %u\n", hook); |
| } |
| return 1; |
| } |
| |
| static inline int |
| cleanup_match(struct ip6t_entry_match *m, unsigned int *i) |
| { |
| if (i && (*i)-- == 0) |
| return 1; |
| |
| if (m->u.kernel.match->destroy) |
| m->u.kernel.match->destroy(m->u.kernel.match, m->data); |
| module_put(m->u.kernel.match->me); |
| return 0; |
| } |
| |
| static inline int |
| check_match(struct ip6t_entry_match *m, |
| const char *name, |
| const struct ip6t_ip6 *ipv6, |
| unsigned int hookmask, |
| unsigned int *i) |
| { |
| struct xt_match *match; |
| int ret; |
| |
| match = try_then_request_module(xt_find_match(AF_INET6, m->u.user.name, |
| m->u.user.revision), |
| "ip6t_%s", m->u.user.name); |
| if (IS_ERR(match) || !match) { |
| duprintf("check_match: `%s' not found\n", m->u.user.name); |
| return match ? PTR_ERR(match) : -ENOENT; |
| } |
| m->u.kernel.match = match; |
| |
| ret = xt_check_match(match, AF_INET6, m->u.match_size - sizeof(*m), |
| name, hookmask, ipv6->proto, |
| ipv6->invflags & IP6T_INV_PROTO); |
| if (ret) |
| goto err; |
| |
| if (m->u.kernel.match->checkentry |
| && !m->u.kernel.match->checkentry(name, ipv6, match, m->data, |
| hookmask)) { |
| duprintf("ip_tables: check failed for `%s'.\n", |
| m->u.kernel.match->name); |
| ret = -EINVAL; |
| goto err; |
| } |
| |
| (*i)++; |
| return 0; |
| err: |
| module_put(m->u.kernel.match->me); |
| return ret; |
| } |
| |
| static struct xt_target ip6t_standard_target; |
| |
| static inline int |
| check_entry(struct ip6t_entry *e, const char *name, unsigned int size, |
| unsigned int *i) |
| { |
| struct ip6t_entry_target *t; |
| struct xt_target *target; |
| int ret; |
| unsigned int j; |
| |
| if (!ip6_checkentry(&e->ipv6)) { |
| duprintf("ip_tables: ip check failed %p %s.\n", e, name); |
| return -EINVAL; |
| } |
| |
| if (e->target_offset + sizeof(struct ip6t_entry_target) > |
| e->next_offset) |
| return -EINVAL; |
| |
| j = 0; |
| ret = IP6T_MATCH_ITERATE(e, check_match, name, &e->ipv6, e->comefrom, &j); |
| if (ret != 0) |
| goto cleanup_matches; |
| |
| t = ip6t_get_target(e); |
| ret = -EINVAL; |
| if (e->target_offset + t->u.target_size > e->next_offset) |
| goto cleanup_matches; |
| target = try_then_request_module(xt_find_target(AF_INET6, |
| t->u.user.name, |
| t->u.user.revision), |
| "ip6t_%s", t->u.user.name); |
| if (IS_ERR(target) || !target) { |
| duprintf("check_entry: `%s' not found\n", t->u.user.name); |
| ret = target ? PTR_ERR(target) : -ENOENT; |
| goto cleanup_matches; |
| } |
| t->u.kernel.target = target; |
| |
| ret = xt_check_target(target, AF_INET6, t->u.target_size - sizeof(*t), |
| name, e->comefrom, e->ipv6.proto, |
| e->ipv6.invflags & IP6T_INV_PROTO); |
| if (ret) |
| goto err; |
| |
| if (t->u.kernel.target->checkentry |
| && !t->u.kernel.target->checkentry(name, e, target, t->data, |
| e->comefrom)) { |
| duprintf("ip_tables: check failed for `%s'.\n", |
| t->u.kernel.target->name); |
| ret = -EINVAL; |
| goto err; |
| } |
| |
| (*i)++; |
| return 0; |
| err: |
| module_put(t->u.kernel.target->me); |
| cleanup_matches: |
| IP6T_MATCH_ITERATE(e, cleanup_match, &j); |
| return ret; |
| } |
| |
| static inline int |
| check_entry_size_and_hooks(struct ip6t_entry *e, |
| struct xt_table_info *newinfo, |
| unsigned char *base, |
| unsigned char *limit, |
| const unsigned int *hook_entries, |
| const unsigned int *underflows, |
| unsigned int *i) |
| { |
| unsigned int h; |
| |
| if ((unsigned long)e % __alignof__(struct ip6t_entry) != 0 |
| || (unsigned char *)e + sizeof(struct ip6t_entry) >= limit) { |
| duprintf("Bad offset %p\n", e); |
| return -EINVAL; |
| } |
| |
| if (e->next_offset |
| < sizeof(struct ip6t_entry) + sizeof(struct ip6t_entry_target)) { |
| duprintf("checking: element %p size %u\n", |
| e, e->next_offset); |
| return -EINVAL; |
| } |
| |
| /* Check hooks & underflows */ |
| for (h = 0; h < NF_IP6_NUMHOOKS; h++) { |
| if ((unsigned char *)e - base == hook_entries[h]) |
| newinfo->hook_entry[h] = hook_entries[h]; |
| if ((unsigned char *)e - base == underflows[h]) |
| newinfo->underflow[h] = underflows[h]; |
| } |
| |
| /* FIXME: underflows must be unconditional, standard verdicts |
| < 0 (not IP6T_RETURN). --RR */ |
| |
| /* Clear counters and comefrom */ |
| e->counters = ((struct xt_counters) { 0, 0 }); |
| e->comefrom = 0; |
| |
| (*i)++; |
| return 0; |
| } |
| |
| static inline int |
| cleanup_entry(struct ip6t_entry *e, unsigned int *i) |
| { |
| struct ip6t_entry_target *t; |
| |
| if (i && (*i)-- == 0) |
| return 1; |
| |
| /* Cleanup all matches */ |
| IP6T_MATCH_ITERATE(e, cleanup_match, NULL); |
| t = ip6t_get_target(e); |
| if (t->u.kernel.target->destroy) |
| t->u.kernel.target->destroy(t->u.kernel.target, t->data); |
| module_put(t->u.kernel.target->me); |
| return 0; |
| } |
| |
| /* Checks and translates the user-supplied table segment (held in |
| newinfo) */ |
| static int |
| translate_table(const char *name, |
| unsigned int valid_hooks, |
| struct xt_table_info *newinfo, |
| void *entry0, |
| unsigned int size, |
| unsigned int number, |
| const unsigned int *hook_entries, |
| const unsigned int *underflows) |
| { |
| unsigned int i; |
| int ret; |
| |
| newinfo->size = size; |
| newinfo->number = number; |
| |
| /* Init all hooks to impossible value. */ |
| for (i = 0; i < NF_IP6_NUMHOOKS; i++) { |
| newinfo->hook_entry[i] = 0xFFFFFFFF; |
| newinfo->underflow[i] = 0xFFFFFFFF; |
| } |
| |
| duprintf("translate_table: size %u\n", newinfo->size); |
| i = 0; |
| /* Walk through entries, checking offsets. */ |
| ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
| check_entry_size_and_hooks, |
| newinfo, |
| entry0, |
| entry0 + size, |
| hook_entries, underflows, &i); |
| if (ret != 0) |
| return ret; |
| |
| if (i != number) { |
| duprintf("translate_table: %u not %u entries\n", |
| i, number); |
| return -EINVAL; |
| } |
| |
| /* Check hooks all assigned */ |
| for (i = 0; i < NF_IP6_NUMHOOKS; i++) { |
| /* Only hooks which are valid */ |
| if (!(valid_hooks & (1 << i))) |
| continue; |
| if (newinfo->hook_entry[i] == 0xFFFFFFFF) { |
| duprintf("Invalid hook entry %u %u\n", |
| i, hook_entries[i]); |
| return -EINVAL; |
| } |
| if (newinfo->underflow[i] == 0xFFFFFFFF) { |
| duprintf("Invalid underflow %u %u\n", |
| i, underflows[i]); |
| return -EINVAL; |
| } |
| } |
| |
| if (!mark_source_chains(newinfo, valid_hooks, entry0)) |
| return -ELOOP; |
| |
| /* Finally, each sanity check must pass */ |
| i = 0; |
| ret = IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
| check_entry, name, size, &i); |
| |
| if (ret != 0) { |
| IP6T_ENTRY_ITERATE(entry0, newinfo->size, |
| cleanup_entry, &i); |
| return ret; |
| } |
| |
| /* And one copy for every other CPU */ |
| for_each_possible_cpu(i) { |
| if (newinfo->entries[i] && newinfo->entries[i] != entry0) |
| memcpy(newinfo->entries[i], entry0, newinfo->size); |
| } |
| |
| return 0; |
| } |
| |
| /* Gets counters. */ |
| static inline int |
| add_entry_to_counter(const struct ip6t_entry *e, |
| struct xt_counters total[], |
| unsigned int *i) |
| { |
| ADD_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); |
| |
| (*i)++; |
| return 0; |
| } |
| |
| static inline int |
| set_entry_to_counter(const struct ip6t_entry *e, |
| struct ip6t_counters total[], |
| unsigned int *i) |
| { |
| SET_COUNTER(total[*i], e->counters.bcnt, e->counters.pcnt); |
| |
| (*i)++; |
| return 0; |
| } |
| |
| static void |
| get_counters(const struct xt_table_info *t, |
| struct xt_counters counters[]) |
| { |
| unsigned int cpu; |
| unsigned int i; |
| unsigned int curcpu; |
| |
| /* Instead of clearing (by a previous call to memset()) |
| * the counters and using adds, we set the counters |
| * with data used by 'current' CPU |
| * We dont care about preemption here. |
| */ |
| curcpu = raw_smp_processor_id(); |
| |
| i = 0; |
| IP6T_ENTRY_ITERATE(t->entries[curcpu], |
| t->size, |
| set_entry_to_counter, |
| counters, |
| &i); |
| |
| for_each_possible_cpu(cpu) { |
| if (cpu == curcpu) |
| continue; |
| i = 0; |
| IP6T_ENTRY_ITERATE(t->entries[cpu], |
| t->size, |
| add_entry_to_counter, |
| counters, |
| &i); |
| } |
| } |
| |
| static int |
| copy_entries_to_user(unsigned int total_size, |
| struct xt_table *table, |
| void __user *userptr) |
| { |
| unsigned int off, num, countersize; |
| struct ip6t_entry *e; |
| struct xt_counters *counters; |
| struct xt_table_info *private = table->private; |
| int ret = 0; |
| void *loc_cpu_entry; |
| |
| /* We need atomic snapshot of counters: rest doesn't change |
| (other than comefrom, which userspace doesn't care |
| about). */ |
| countersize = sizeof(struct xt_counters) * private->number; |
| counters = vmalloc(countersize); |
| |
| if (counters == NULL) |
| return -ENOMEM; |
| |
| /* First, sum counters... */ |
| write_lock_bh(&table->lock); |
| get_counters(private, counters); |
| write_unlock_bh(&table->lock); |
| |
| /* choose the copy that is on ourc node/cpu */ |
| loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
| if (copy_to_user(userptr, loc_cpu_entry, total_size) != 0) { |
| ret = -EFAULT; |
| goto free_counters; |
| } |
| |
| /* FIXME: use iterator macros --RR */ |
| /* ... then go back and fix counters and names */ |
| for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){ |
| unsigned int i; |
| struct ip6t_entry_match *m; |
| struct ip6t_entry_target *t; |
| |
| e = (struct ip6t_entry *)(loc_cpu_entry + off); |
| if (copy_to_user(userptr + off |
| + offsetof(struct ip6t_entry, counters), |
| &counters[num], |
| sizeof(counters[num])) != 0) { |
| ret = -EFAULT; |
| goto free_counters; |
| } |
| |
| for (i = sizeof(struct ip6t_entry); |
| i < e->target_offset; |
| i += m->u.match_size) { |
| m = (void *)e + i; |
| |
| if (copy_to_user(userptr + off + i |
| + offsetof(struct ip6t_entry_match, |
| u.user.name), |
| m->u.kernel.match->name, |
| strlen(m->u.kernel.match->name)+1) |
| != 0) { |
| ret = -EFAULT; |
| goto free_counters; |
| } |
| } |
| |
| t = ip6t_get_target(e); |
| if (copy_to_user(userptr + off + e->target_offset |
| + offsetof(struct ip6t_entry_target, |
| u.user.name), |
| t->u.kernel.target->name, |
| strlen(t->u.kernel.target->name)+1) != 0) { |
| ret = -EFAULT; |
| goto free_counters; |
| } |
| } |
| |
| free_counters: |
| vfree(counters); |
| return ret; |
| } |
| |
| static int |
| get_entries(const struct ip6t_get_entries *entries, |
| struct ip6t_get_entries __user *uptr) |
| { |
| int ret; |
| struct xt_table *t; |
| |
| t = xt_find_table_lock(AF_INET6, entries->name); |
| if (t && !IS_ERR(t)) { |
| struct xt_table_info *private = t->private; |
| duprintf("t->private->number = %u\n", private->number); |
| if (entries->size == private->size) |
| ret = copy_entries_to_user(private->size, |
| t, uptr->entrytable); |
| else { |
| duprintf("get_entries: I've got %u not %u!\n", |
| private->size, entries->size); |
| ret = -EINVAL; |
| } |
| module_put(t->me); |
| xt_table_unlock(t); |
| } else |
| ret = t ? PTR_ERR(t) : -ENOENT; |
| |
| return ret; |
| } |
| |
| static int |
| do_replace(void __user *user, unsigned int len) |
| { |
| int ret; |
| struct ip6t_replace tmp; |
| struct xt_table *t; |
| struct xt_table_info *newinfo, *oldinfo; |
| struct xt_counters *counters; |
| void *loc_cpu_entry, *loc_cpu_old_entry; |
| |
| if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| return -EFAULT; |
| |
| /* overflow check */ |
| if (tmp.size >= (INT_MAX - sizeof(struct xt_table_info)) / NR_CPUS - |
| SMP_CACHE_BYTES) |
| return -ENOMEM; |
| if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) |
| return -ENOMEM; |
| |
| newinfo = xt_alloc_table_info(tmp.size); |
| if (!newinfo) |
| return -ENOMEM; |
| |
| /* choose the copy that is on our node/cpu */ |
| loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; |
| if (copy_from_user(loc_cpu_entry, user + sizeof(tmp), |
| tmp.size) != 0) { |
| ret = -EFAULT; |
| goto free_newinfo; |
| } |
| |
| counters = vmalloc(tmp.num_counters * sizeof(struct xt_counters)); |
| if (!counters) { |
| ret = -ENOMEM; |
| goto free_newinfo; |
| } |
| |
| ret = translate_table(tmp.name, tmp.valid_hooks, |
| newinfo, loc_cpu_entry, tmp.size, tmp.num_entries, |
| tmp.hook_entry, tmp.underflow); |
| if (ret != 0) |
| goto free_newinfo_counters; |
| |
| duprintf("ip_tables: Translated table\n"); |
| |
| t = try_then_request_module(xt_find_table_lock(AF_INET6, tmp.name), |
| "ip6table_%s", tmp.name); |
| if (!t || IS_ERR(t)) { |
| ret = t ? PTR_ERR(t) : -ENOENT; |
| goto free_newinfo_counters_untrans; |
| } |
| |
| /* You lied! */ |
| if (tmp.valid_hooks != t->valid_hooks) { |
| duprintf("Valid hook crap: %08X vs %08X\n", |
| tmp.valid_hooks, t->valid_hooks); |
| ret = -EINVAL; |
| goto put_module; |
| } |
| |
| oldinfo = xt_replace_table(t, tmp.num_counters, newinfo, &ret); |
| if (!oldinfo) |
| goto put_module; |
| |
| /* Update module usage count based on number of rules */ |
| duprintf("do_replace: oldnum=%u, initnum=%u, newnum=%u\n", |
| oldinfo->number, oldinfo->initial_entries, newinfo->number); |
| if ((oldinfo->number > oldinfo->initial_entries) || |
| (newinfo->number <= oldinfo->initial_entries)) |
| module_put(t->me); |
| if ((oldinfo->number > oldinfo->initial_entries) && |
| (newinfo->number <= oldinfo->initial_entries)) |
| module_put(t->me); |
| |
| /* Get the old counters. */ |
| get_counters(oldinfo, counters); |
| /* Decrease module usage counts and free resource */ |
| loc_cpu_old_entry = oldinfo->entries[raw_smp_processor_id()]; |
| IP6T_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL); |
| xt_free_table_info(oldinfo); |
| if (copy_to_user(tmp.counters, counters, |
| sizeof(struct xt_counters) * tmp.num_counters) != 0) |
| ret = -EFAULT; |
| vfree(counters); |
| xt_table_unlock(t); |
| return ret; |
| |
| put_module: |
| module_put(t->me); |
| xt_table_unlock(t); |
| free_newinfo_counters_untrans: |
| IP6T_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL); |
| free_newinfo_counters: |
| vfree(counters); |
| free_newinfo: |
| xt_free_table_info(newinfo); |
| return ret; |
| } |
| |
| /* We're lazy, and add to the first CPU; overflow works its fey magic |
| * and everything is OK. */ |
| static inline int |
| add_counter_to_entry(struct ip6t_entry *e, |
| const struct xt_counters addme[], |
| unsigned int *i) |
| { |
| #if 0 |
| duprintf("add_counter: Entry %u %lu/%lu + %lu/%lu\n", |
| *i, |
| (long unsigned int)e->counters.pcnt, |
| (long unsigned int)e->counters.bcnt, |
| (long unsigned int)addme[*i].pcnt, |
| (long unsigned int)addme[*i].bcnt); |
| #endif |
| |
| ADD_COUNTER(e->counters, addme[*i].bcnt, addme[*i].pcnt); |
| |
| (*i)++; |
| return 0; |
| } |
| |
| static int |
| do_add_counters(void __user *user, unsigned int len) |
| { |
| unsigned int i; |
| struct xt_counters_info tmp, *paddc; |
| struct xt_table_info *private; |
| struct xt_table *t; |
| int ret = 0; |
| void *loc_cpu_entry; |
| |
| if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| return -EFAULT; |
| |
| if (len != sizeof(tmp) + tmp.num_counters*sizeof(struct xt_counters)) |
| return -EINVAL; |
| |
| paddc = vmalloc(len); |
| if (!paddc) |
| return -ENOMEM; |
| |
| if (copy_from_user(paddc, user, len) != 0) { |
| ret = -EFAULT; |
| goto free; |
| } |
| |
| t = xt_find_table_lock(AF_INET6, tmp.name); |
| if (!t || IS_ERR(t)) { |
| ret = t ? PTR_ERR(t) : -ENOENT; |
| goto free; |
| } |
| |
| write_lock_bh(&t->lock); |
| private = t->private; |
| if (private->number != tmp.num_counters) { |
| ret = -EINVAL; |
| goto unlock_up_free; |
| } |
| |
| i = 0; |
| /* Choose the copy that is on our node */ |
| loc_cpu_entry = private->entries[smp_processor_id()]; |
| IP6T_ENTRY_ITERATE(loc_cpu_entry, |
| private->size, |
| add_counter_to_entry, |
| paddc->counters, |
| &i); |
| unlock_up_free: |
| write_unlock_bh(&t->lock); |
| xt_table_unlock(t); |
| module_put(t->me); |
| free: |
| vfree(paddc); |
| |
| return ret; |
| } |
| |
| static int |
| do_ip6t_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) |
| { |
| int ret; |
| |
| if (!capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| switch (cmd) { |
| case IP6T_SO_SET_REPLACE: |
| ret = do_replace(user, len); |
| break; |
| |
| case IP6T_SO_SET_ADD_COUNTERS: |
| ret = do_add_counters(user, len); |
| break; |
| |
| default: |
| duprintf("do_ip6t_set_ctl: unknown request %i\n", cmd); |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| static int |
| do_ip6t_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| { |
| int ret; |
| |
| if (!capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| switch (cmd) { |
| case IP6T_SO_GET_INFO: { |
| char name[IP6T_TABLE_MAXNAMELEN]; |
| struct xt_table *t; |
| |
| if (*len != sizeof(struct ip6t_getinfo)) { |
| duprintf("length %u != %u\n", *len, |
| sizeof(struct ip6t_getinfo)); |
| ret = -EINVAL; |
| break; |
| } |
| |
| if (copy_from_user(name, user, sizeof(name)) != 0) { |
| ret = -EFAULT; |
| break; |
| } |
| name[IP6T_TABLE_MAXNAMELEN-1] = '\0'; |
| |
| t = try_then_request_module(xt_find_table_lock(AF_INET6, name), |
| "ip6table_%s", name); |
| if (t && !IS_ERR(t)) { |
| struct ip6t_getinfo info; |
| struct xt_table_info *private = t->private; |
| |
| info.valid_hooks = t->valid_hooks; |
| memcpy(info.hook_entry, private->hook_entry, |
| sizeof(info.hook_entry)); |
| memcpy(info.underflow, private->underflow, |
| sizeof(info.underflow)); |
| info.num_entries = private->number; |
| info.size = private->size; |
| memcpy(info.name, name, sizeof(info.name)); |
| |
| if (copy_to_user(user, &info, *len) != 0) |
| ret = -EFAULT; |
| else |
| ret = 0; |
| xt_table_unlock(t); |
| module_put(t->me); |
| } else |
| ret = t ? PTR_ERR(t) : -ENOENT; |
| } |
| break; |
| |
| case IP6T_SO_GET_ENTRIES: { |
| struct ip6t_get_entries get; |
| |
| if (*len < sizeof(get)) { |
| duprintf("get_entries: %u < %u\n", *len, sizeof(get)); |
| ret = -EINVAL; |
| } else if (copy_from_user(&get, user, sizeof(get)) != 0) { |
| ret = -EFAULT; |
| } else if (*len != sizeof(struct ip6t_get_entries) + get.size) { |
| duprintf("get_entries: %u != %u\n", *len, |
| sizeof(struct ip6t_get_entries) + get.size); |
| ret = -EINVAL; |
| } else |
| ret = get_entries(&get, user); |
| break; |
| } |
| |
| case IP6T_SO_GET_REVISION_MATCH: |
| case IP6T_SO_GET_REVISION_TARGET: { |
| struct ip6t_get_revision rev; |
| int target; |
| |
| if (*len != sizeof(rev)) { |
| ret = -EINVAL; |
| break; |
| } |
| if (copy_from_user(&rev, user, sizeof(rev)) != 0) { |
| ret = -EFAULT; |
| break; |
| } |
| |
| if (cmd == IP6T_SO_GET_REVISION_TARGET) |
| target = 1; |
| else |
| target = 0; |
| |
| try_then_request_module(xt_find_revision(AF_INET6, rev.name, |
| rev.revision, |
| target, &ret), |
| "ip6t_%s", rev.name); |
| break; |
| } |
| |
| default: |
| duprintf("do_ip6t_get_ctl: unknown request %i\n", cmd); |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| int ip6t_register_table(struct xt_table *table, |
| const struct ip6t_replace *repl) |
| { |
| int ret; |
| struct xt_table_info *newinfo; |
| static struct xt_table_info bootstrap |
| = { 0, 0, 0, { 0 }, { 0 }, { } }; |
| void *loc_cpu_entry; |
| |
| newinfo = xt_alloc_table_info(repl->size); |
| if (!newinfo) |
| return -ENOMEM; |
| |
| /* choose the copy on our node/cpu */ |
| loc_cpu_entry = newinfo->entries[raw_smp_processor_id()]; |
| memcpy(loc_cpu_entry, repl->entries, repl->size); |
| |
| ret = translate_table(table->name, table->valid_hooks, |
| newinfo, loc_cpu_entry, repl->size, |
| repl->num_entries, |
| repl->hook_entry, |
| repl->underflow); |
| if (ret != 0) { |
| xt_free_table_info(newinfo); |
| return ret; |
| } |
| |
| ret = xt_register_table(table, &bootstrap, newinfo); |
| if (ret != 0) { |
| xt_free_table_info(newinfo); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| void ip6t_unregister_table(struct xt_table *table) |
| { |
| struct xt_table_info *private; |
| void *loc_cpu_entry; |
| |
| private = xt_unregister_table(table); |
| |
| /* Decrease module usage counts and free resources */ |
| loc_cpu_entry = private->entries[raw_smp_processor_id()]; |
| IP6T_ENTRY_ITERATE(loc_cpu_entry, private->size, cleanup_entry, NULL); |
| xt_free_table_info(private); |
| } |
| |
| /* Returns 1 if the type and code is matched by the range, 0 otherwise */ |
| static inline int |
| icmp6_type_code_match(u_int8_t test_type, u_int8_t min_code, u_int8_t max_code, |
| u_int8_t type, u_int8_t code, |
| int invert) |
| { |
| return (type == test_type && code >= min_code && code <= max_code) |
| ^ invert; |
| } |
| |
| static bool |
| icmp6_match(const struct sk_buff *skb, |
| const struct net_device *in, |
| const struct net_device *out, |
| const struct xt_match *match, |
| const void *matchinfo, |
| int offset, |
| unsigned int protoff, |
| bool *hotdrop) |
| { |
| struct icmp6hdr _icmp, *ic; |
| const struct ip6t_icmp *icmpinfo = matchinfo; |
| |
| /* Must not be a fragment. */ |
| if (offset) |
| return false; |
| |
| ic = skb_header_pointer(skb, protoff, sizeof(_icmp), &_icmp); |
| if (ic == NULL) { |
| /* We've been asked to examine this packet, and we |
| can't. Hence, no choice but to drop. */ |
| duprintf("Dropping evil ICMP tinygram.\n"); |
| *hotdrop = true; |
| return false; |
| } |
| |
| return icmp6_type_code_match(icmpinfo->type, |
| icmpinfo->code[0], |
| icmpinfo->code[1], |
| ic->icmp6_type, ic->icmp6_code, |
| !!(icmpinfo->invflags&IP6T_ICMP_INV)); |
| } |
| |
| /* Called when user tries to insert an entry of this type. */ |
| static int |
| icmp6_checkentry(const char *tablename, |
| const void *entry, |
| const struct xt_match *match, |
| void *matchinfo, |
| unsigned int hook_mask) |
| { |
| const struct ip6t_icmp *icmpinfo = matchinfo; |
| |
| /* Must specify no unknown invflags */ |
| return !(icmpinfo->invflags & ~IP6T_ICMP_INV); |
| } |
| |
| /* The built-in targets: standard (NULL) and error. */ |
| static struct xt_target ip6t_standard_target = { |
| .name = IP6T_STANDARD_TARGET, |
| .targetsize = sizeof(int), |
| .family = AF_INET6, |
| }; |
| |
| static struct xt_target ip6t_error_target = { |
| .name = IP6T_ERROR_TARGET, |
| .target = ip6t_error, |
| .targetsize = IP6T_FUNCTION_MAXNAMELEN, |
| .family = AF_INET6, |
| }; |
| |
| static struct nf_sockopt_ops ip6t_sockopts = { |
| .pf = PF_INET6, |
| .set_optmin = IP6T_BASE_CTL, |
| .set_optmax = IP6T_SO_SET_MAX+1, |
| .set = do_ip6t_set_ctl, |
| .get_optmin = IP6T_BASE_CTL, |
| .get_optmax = IP6T_SO_GET_MAX+1, |
| .get = do_ip6t_get_ctl, |
| }; |
| |
| static struct xt_match icmp6_matchstruct = { |
| .name = "icmp6", |
| .match = &icmp6_match, |
| .matchsize = sizeof(struct ip6t_icmp), |
| .checkentry = icmp6_checkentry, |
| .proto = IPPROTO_ICMPV6, |
| .family = AF_INET6, |
| }; |
| |
| static int __init ip6_tables_init(void) |
| { |
| int ret; |
| |
| ret = xt_proto_init(AF_INET6); |
| if (ret < 0) |
| goto err1; |
| |
| /* Noone else will be downing sem now, so we won't sleep */ |
| ret = xt_register_target(&ip6t_standard_target); |
| if (ret < 0) |
| goto err2; |
| ret = xt_register_target(&ip6t_error_target); |
| if (ret < 0) |
| goto err3; |
| ret = xt_register_match(&icmp6_matchstruct); |
| if (ret < 0) |
| goto err4; |
| |
| /* Register setsockopt */ |
| ret = nf_register_sockopt(&ip6t_sockopts); |
| if (ret < 0) |
| goto err5; |
| |
| printk("ip6_tables: (C) 2000-2006 Netfilter Core Team\n"); |
| return 0; |
| |
| err5: |
| xt_unregister_match(&icmp6_matchstruct); |
| err4: |
| xt_unregister_target(&ip6t_error_target); |
| err3: |
| xt_unregister_target(&ip6t_standard_target); |
| err2: |
| xt_proto_fini(AF_INET6); |
| err1: |
| return ret; |
| } |
| |
| static void __exit ip6_tables_fini(void) |
| { |
| nf_unregister_sockopt(&ip6t_sockopts); |
| xt_unregister_match(&icmp6_matchstruct); |
| xt_unregister_target(&ip6t_error_target); |
| xt_unregister_target(&ip6t_standard_target); |
| xt_proto_fini(AF_INET6); |
| } |
| |
| /* |
| * find the offset to specified header or the protocol number of last header |
| * if target < 0. "last header" is transport protocol header, ESP, or |
| * "No next header". |
| * |
| * If target header is found, its offset is set in *offset and return protocol |
| * number. Otherwise, return -1. |
| * |
| * If the first fragment doesn't contain the final protocol header or |
| * NEXTHDR_NONE it is considered invalid. |
| * |
| * Note that non-1st fragment is special case that "the protocol number |
| * of last header" is "next header" field in Fragment header. In this case, |
| * *offset is meaningless and fragment offset is stored in *fragoff if fragoff |
| * isn't NULL. |
| * |
| */ |
| int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset, |
| int target, unsigned short *fragoff) |
| { |
| unsigned int start = skb_network_offset(skb) + sizeof(struct ipv6hdr); |
| u8 nexthdr = ipv6_hdr(skb)->nexthdr; |
| unsigned int len = skb->len - start; |
| |
| if (fragoff) |
| *fragoff = 0; |
| |
| while (nexthdr != target) { |
| struct ipv6_opt_hdr _hdr, *hp; |
| unsigned int hdrlen; |
| |
| if ((!ipv6_ext_hdr(nexthdr)) || nexthdr == NEXTHDR_NONE) { |
| if (target < 0) |
| break; |
| return -ENOENT; |
| } |
| |
| hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr); |
| if (hp == NULL) |
| return -EBADMSG; |
| if (nexthdr == NEXTHDR_FRAGMENT) { |
| unsigned short _frag_off; |
| __be16 *fp; |
| fp = skb_header_pointer(skb, |
| start+offsetof(struct frag_hdr, |
| frag_off), |
| sizeof(_frag_off), |
| &_frag_off); |
| if (fp == NULL) |
| return -EBADMSG; |
| |
| _frag_off = ntohs(*fp) & ~0x7; |
| if (_frag_off) { |
| if (target < 0 && |
| ((!ipv6_ext_hdr(hp->nexthdr)) || |
| hp->nexthdr == NEXTHDR_NONE)) { |
| if (fragoff) |
| *fragoff = _frag_off; |
| return hp->nexthdr; |
| } |
| return -ENOENT; |
| } |
| hdrlen = 8; |
| } else if (nexthdr == NEXTHDR_AUTH) |
| hdrlen = (hp->hdrlen + 2) << 2; |
| else |
| hdrlen = ipv6_optlen(hp); |
| |
| nexthdr = hp->nexthdr; |
| len -= hdrlen; |
| start += hdrlen; |
| } |
| |
| *offset = start; |
| return nexthdr; |
| } |
| |
| EXPORT_SYMBOL(ip6t_register_table); |
| EXPORT_SYMBOL(ip6t_unregister_table); |
| EXPORT_SYMBOL(ip6t_do_table); |
| EXPORT_SYMBOL(ip6t_ext_hdr); |
| EXPORT_SYMBOL(ipv6_find_hdr); |
| |
| module_init(ip6_tables_init); |
| module_exit(ip6_tables_fini); |