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- /*
- * 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.
- *
- * 19 Jan 2002 Harald Welte <laforge@gnumonks.org>
- * - increase module usage count as soon as we have rules inside
- * a table
- * 08 Oct 2005 Harald Welte <lafore@netfilter.org>
- * - Generalize into "x_tables" layer and "{ip,ip6,arp}_tables"
- */
- #include <linux/cache.h>
- #include <linux/capability.h>
- #include <linux/skbuff.h>
- #include <linux/kmod.h>
- #include <linux/vmalloc.h>
- #include <linux/netdevice.h>
- #include <linux/module.h>
- #include <linux/icmp.h>
- #include <net/ip.h>
- #include <net/compat.h>
- #include <asm/uaccess.h>
- #include <linux/mutex.h>
- #include <linux/proc_fs.h>
- #include <linux/err.h>
- #include <linux/cpumask.h>
- #include <linux/netfilter/x_tables.h>
- #include <linux/netfilter_ipv4/ip_tables.h>
- MODULE_LICENSE("GPL");
- MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
- MODULE_DESCRIPTION("IPv4 packet filter");
- /*#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. */
- /* Returns whether matches rule or not. */
- static inline int
- ip_packet_match(const struct iphdr *ip,
- const char *indev,
- const char *outdev,
- const struct ipt_ip *ipinfo,
- int isfrag)
- {
- size_t i;
- unsigned long ret;
- #define FWINV(bool,invflg) ((bool) ^ !!(ipinfo->invflags & invflg))
- if (FWINV((ip->saddr&ipinfo->smsk.s_addr) != ipinfo->src.s_addr,
- IPT_INV_SRCIP)
- || FWINV((ip->daddr&ipinfo->dmsk.s_addr) != ipinfo->dst.s_addr,
- IPT_INV_DSTIP)) {
- dprintf("Source or dest mismatch.\n");
- dprintf("SRC: %u.%u.%u.%u. Mask: %u.%u.%u.%u. Target: %u.%u.%u.%u.%s\n",
- NIPQUAD(ip->saddr),
- NIPQUAD(ipinfo->smsk.s_addr),
- NIPQUAD(ipinfo->src.s_addr),
- ipinfo->invflags & IPT_INV_SRCIP ? " (INV)" : "");
- dprintf("DST: %u.%u.%u.%u Mask: %u.%u.%u.%u Target: %u.%u.%u.%u.%s\n",
- NIPQUAD(ip->daddr),
- NIPQUAD(ipinfo->dmsk.s_addr),
- NIPQUAD(ipinfo->dst.s_addr),
- ipinfo->invflags & IPT_INV_DSTIP ? " (INV)" : "");
- return 0;
- }
- /* 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 *)ipinfo->iniface)[i])
- & ((const unsigned long *)ipinfo->iniface_mask)[i];
- }
- if (FWINV(ret != 0, IPT_INV_VIA_IN)) {
- dprintf("VIA in mismatch (%s vs %s).%s\n",
- indev, ipinfo->iniface,
- ipinfo->invflags&IPT_INV_VIA_IN ?" (INV)":"");
- return 0;
- }
- for (i = 0, ret = 0; i < IFNAMSIZ/sizeof(unsigned long); i++) {
- ret |= (((const unsigned long *)outdev)[i]
- ^ ((const unsigned long *)ipinfo->outiface)[i])
- & ((const unsigned long *)ipinfo->outiface_mask)[i];
- }
- if (FWINV(ret != 0, IPT_INV_VIA_OUT)) {
- dprintf("VIA out mismatch (%s vs %s).%s\n",
- outdev, ipinfo->outiface,
- ipinfo->invflags&IPT_INV_VIA_OUT ?" (INV)":"");
- return 0;
- }
- /* Check specific protocol */
- if (ipinfo->proto
- && FWINV(ip->protocol != ipinfo->proto, IPT_INV_PROTO)) {
- dprintf("Packet protocol %hi does not match %hi.%s\n",
- ip->protocol, ipinfo->proto,
- ipinfo->invflags&IPT_INV_PROTO ? " (INV)":"");
- return 0;
- }
- /* If we have a fragment rule but the packet is not a fragment
- * then we return zero */
- if (FWINV((ipinfo->flags&IPT_F_FRAG) && !isfrag, IPT_INV_FRAG)) {
- dprintf("Fragment rule but not fragment.%s\n",
- ipinfo->invflags & IPT_INV_FRAG ? " (INV)" : "");
- return 0;
- }
- return 1;
- }
- static inline int
- ip_checkentry(const struct ipt_ip *ip)
- {
- if (ip->flags & ~IPT_F_MASK) {
- duprintf("Unknown flag bits set: %08X\n",
- ip->flags & ~IPT_F_MASK);
- return 0;
- }
- if (ip->invflags & ~IPT_INV_MASK) {
- duprintf("Unknown invflag bits set: %08X\n",
- ip->invflags & ~IPT_INV_MASK);
- return 0;
- }
- return 1;
- }
- static unsigned int
- ipt_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("ip_tables: error: `%s'\n", (char *)targinfo);
- return NF_DROP;
- }
- static inline
- int do_match(struct ipt_entry_match *m,
- const struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- int offset,
- int *hotdrop)
- {
- /* Stop iteration if it doesn't match */
- if (!m->u.kernel.match->match(skb, in, out, m->u.kernel.match, m->data,
- offset, skb->nh.iph->ihl*4, hotdrop))
- return 1;
- else
- return 0;
- }
- static inline struct ipt_entry *
- get_entry(void *base, unsigned int offset)
- {
- return (struct ipt_entry *)(base + offset);
- }
- /* Returns one of the generic firewall policies, like NF_ACCEPT. */
- unsigned int
- ipt_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))));
- u_int16_t offset;
- struct iphdr *ip;
- u_int16_t datalen;
- int hotdrop = 0;
- /* Initializing verdict to NF_DROP keeps gcc happy. */
- unsigned int verdict = NF_DROP;
- const char *indev, *outdev;
- void *table_base;
- struct ipt_entry *e, *back;
- struct xt_table_info *private;
- /* Initialization */
- ip = (*pskb)->nh.iph;
- datalen = (*pskb)->len - ip->ihl * 4;
- 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. */
- offset = ntohs(ip->frag_off) & IP_OFFSET;
- read_lock_bh(&table->lock);
- IP_NF_ASSERT(table->valid_hooks & (1 << hook));
- private = table->private;
- 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 (ip_packet_match(ip, indev, outdev, &e->ip, offset)) {
- struct ipt_entry_target *t;
- if (IPT_MATCH_ITERATE(e, do_match,
- *pskb, in, out,
- offset, &hotdrop) != 0)
- goto no_match;
- ADD_COUNTER(e->counters, ntohs(ip->tot_len), 1);
- t = ipt_get_target(e);
- IP_NF_ASSERT(t->u.kernel.target);
- /* Standard target? */
- if (!t->u.kernel.target->target) {
- int v;
- v = ((struct ipt_standard_target *)t)->verdict;
- if (v < 0) {
- /* Pop from stack? */
- if (v != IPT_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->ip.flags & IPT_F_GOTO)) {
- /* Save old back ptr in next entry */
- struct ipt_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 ipt_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 ipt_entry *)table_base)->comefrom
- != 0xeeeeeeec
- && verdict == IPT_CONTINUE) {
- printk("Target %s reentered!\n",
- t->u.kernel.target->name);
- verdict = NF_DROP;
- }
- ((struct ipt_entry *)table_base)->comefrom
- = 0x57acc001;
- #endif
- /* Target might have changed stuff. */
- ip = (*pskb)->nh.iph;
- datalen = (*pskb)->len - ip->ihl * 4;
- if (verdict == IPT_CONTINUE)
- e = (void *)e + e->next_offset;
- else
- /* Verdict */
- break;
- }
- } else {
- no_match:
- e = (void *)e + e->next_offset;
- }
- } while (!hotdrop);
- 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 ipt_ip *ip)
- {
- unsigned int i;
- for (i = 0; i < sizeof(*ip)/sizeof(__u32); i++)
- if (((__u32 *)ip)[i])
- return 0;
- return 1;
- }
- /* 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_IP_NUMHOOKS; hook++) {
- unsigned int pos = newinfo->hook_entry[hook];
- struct ipt_entry *e
- = (struct ipt_entry *)(entry0 + pos);
- if (!(valid_hooks & (1 << hook)))
- continue;
- /* Set initial back pointer. */
- e->counters.pcnt = pos;
- for (;;) {
- struct ipt_standard_target *t
- = (void *)ipt_get_target(e);
- int visited = e->comefrom & (1 << hook);
- if (e->comefrom & (1 << NF_IP_NUMHOOKS)) {
- printk("iptables: loop hook %u pos %u %08X.\n",
- hook, pos, e->comefrom);
- return 0;
- }
- e->comefrom
- |= ((1 << hook) | (1 << NF_IP_NUMHOOKS));
- /* Unconditional return/END. */
- if ((e->target_offset == sizeof(struct ipt_entry)
- && (strcmp(t->target.u.user.name,
- IPT_STANDARD_TARGET) == 0)
- && t->verdict < 0
- && unconditional(&e->ip)) || 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_IP_NUMHOOKS);
- #ifdef DEBUG_IP_FIREWALL_USER
- if (e->comefrom
- & (1 << NF_IP_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 ipt_entry *)
- (entry0 + pos);
- } while (oldpos == pos + e->next_offset);
- /* Move along one */
- size = e->next_offset;
- e = (struct ipt_entry *)
- (entry0 + pos + size);
- e->counters.pcnt = pos;
- pos += size;
- } else {
- int newpos = t->verdict;
- if (strcmp(t->target.u.user.name,
- IPT_STANDARD_TARGET) == 0
- && newpos >= 0) {
- if (newpos > newinfo->size -
- sizeof(struct ipt_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 ipt_entry *)
- (entry0 + newpos);
- e->counters.pcnt = pos;
- pos = newpos;
- }
- }
- next:
- duprintf("Finished chain %u\n", hook);
- }
- return 1;
- }
- static inline int
- cleanup_match(struct ipt_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_entry(struct ipt_entry *e, const char *name)
- {
- struct ipt_entry_target *t;
- if (!ip_checkentry(&e->ip)) {
- duprintf("ip_tables: ip check failed %p %s.\n", e, name);
- return -EINVAL;
- }
- if (e->target_offset + sizeof(struct ipt_entry_target) > e->next_offset)
- return -EINVAL;
- t = ipt_get_target(e);
- if (e->target_offset + t->u.target_size > e->next_offset)
- return -EINVAL;
- return 0;
- }
- static inline int check_match(struct ipt_entry_match *m, const char *name,
- const struct ipt_ip *ip, unsigned int hookmask)
- {
- struct xt_match *match;
- int ret;
- match = m->u.kernel.match;
- ret = xt_check_match(match, AF_INET, m->u.match_size - sizeof(*m),
- name, hookmask, ip->proto,
- ip->invflags & IPT_INV_PROTO);
- if (!ret && m->u.kernel.match->checkentry
- && !m->u.kernel.match->checkentry(name, ip, match, m->data,
- hookmask)) {
- duprintf("ip_tables: check failed for `%s'.\n",
- m->u.kernel.match->name);
- ret = -EINVAL;
- }
- return ret;
- }
- static inline int
- find_check_match(struct ipt_entry_match *m,
- const char *name,
- const struct ipt_ip *ip,
- unsigned int hookmask,
- unsigned int *i)
- {
- struct xt_match *match;
- int ret;
- match = try_then_request_module(xt_find_match(AF_INET, m->u.user.name,
- m->u.user.revision),
- "ipt_%s", m->u.user.name);
- if (IS_ERR(match) || !match) {
- duprintf("find_check_match: `%s' not found\n", m->u.user.name);
- return match ? PTR_ERR(match) : -ENOENT;
- }
- m->u.kernel.match = match;
- ret = check_match(m, name, ip, hookmask);
- if (ret)
- goto err;
- (*i)++;
- return 0;
- err:
- module_put(m->u.kernel.match->me);
- return ret;
- }
- static inline int check_target(struct ipt_entry *e, const char *name)
- {
- struct ipt_entry_target *t;
- struct xt_target *target;
- int ret;
- t = ipt_get_target(e);
- target = t->u.kernel.target;
- ret = xt_check_target(target, AF_INET, t->u.target_size - sizeof(*t),
- name, e->comefrom, e->ip.proto,
- e->ip.invflags & IPT_INV_PROTO);
- if (!ret && 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;
- }
- return ret;
- }
- static inline int
- find_check_entry(struct ipt_entry *e, const char *name, unsigned int size,
- unsigned int *i)
- {
- struct ipt_entry_target *t;
- struct xt_target *target;
- int ret;
- unsigned int j;
- ret = check_entry(e, name);
- if (ret)
- return ret;
- j = 0;
- ret = IPT_MATCH_ITERATE(e, find_check_match, name, &e->ip,
- e->comefrom, &j);
- if (ret != 0)
- goto cleanup_matches;
- t = ipt_get_target(e);
- target = try_then_request_module(xt_find_target(AF_INET,
- t->u.user.name,
- t->u.user.revision),
- "ipt_%s", t->u.user.name);
- if (IS_ERR(target) || !target) {
- duprintf("find_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 = check_target(e, name);
- if (ret)
- goto err;
- (*i)++;
- return 0;
- err:
- module_put(t->u.kernel.target->me);
- cleanup_matches:
- IPT_MATCH_ITERATE(e, cleanup_match, &j);
- return ret;
- }
- static inline int
- check_entry_size_and_hooks(struct ipt_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 ipt_entry) != 0
- || (unsigned char *)e + sizeof(struct ipt_entry) >= limit) {
- duprintf("Bad offset %p\n", e);
- return -EINVAL;
- }
- if (e->next_offset
- < sizeof(struct ipt_entry) + sizeof(struct ipt_entry_target)) {
- duprintf("checking: element %p size %u\n",
- e, e->next_offset);
- return -EINVAL;
- }
- /* Check hooks & underflows */
- for (h = 0; h < NF_IP_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 IPT_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 ipt_entry *e, unsigned int *i)
- {
- struct ipt_entry_target *t;
- if (i && (*i)-- == 0)
- return 1;
- /* Cleanup all matches */
- IPT_MATCH_ITERATE(e, cleanup_match, NULL);
- t = ipt_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_IP_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 = IPT_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_IP_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 = IPT_ENTRY_ITERATE(entry0, newinfo->size,
- find_check_entry, name, size, &i);
- if (ret != 0) {
- IPT_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 ret;
- }
- /* Gets counters. */
- static inline int
- add_entry_to_counter(const struct ipt_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 ipt_entry *e,
- struct ipt_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;
- IPT_ENTRY_ITERATE(t->entries[curcpu],
- t->size,
- set_entry_to_counter,
- counters,
- &i);
- for_each_possible_cpu(cpu) {
- if (cpu == curcpu)
- continue;
- i = 0;
- IPT_ENTRY_ITERATE(t->entries[cpu],
- t->size,
- add_entry_to_counter,
- counters,
- &i);
- }
- }
- static inline struct xt_counters * alloc_counters(struct xt_table *table)
- {
- unsigned int countersize;
- struct xt_counters *counters;
- struct xt_table_info *private = table->private;
- /* 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_node(countersize, numa_node_id());
- if (counters == NULL)
- return ERR_PTR(-ENOMEM);
- /* First, sum counters... */
- write_lock_bh(&table->lock);
- get_counters(private, counters);
- write_unlock_bh(&table->lock);
- return counters;
- }
- static int
- copy_entries_to_user(unsigned int total_size,
- struct xt_table *table,
- void __user *userptr)
- {
- unsigned int off, num;
- struct ipt_entry *e;
- struct xt_counters *counters;
- struct xt_table_info *private = table->private;
- int ret = 0;
- void *loc_cpu_entry;
- counters = alloc_counters(table);
- if (IS_ERR(counters))
- return PTR_ERR(counters);
- /* choose the copy that is on our node/cpu, ...
- * This choice is lazy (because current thread is
- * allowed to migrate to another cpu)
- */
- loc_cpu_entry = private->entries[raw_smp_processor_id()];
- /* ... then copy entire thing ... */
- 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 ipt_entry_match *m;
- struct ipt_entry_target *t;
- e = (struct ipt_entry *)(loc_cpu_entry + off);
- if (copy_to_user(userptr + off
- + offsetof(struct ipt_entry, counters),
- &counters[num],
- sizeof(counters[num])) != 0) {
- ret = -EFAULT;
- goto free_counters;
- }
- for (i = sizeof(struct ipt_entry);
- i < e->target_offset;
- i += m->u.match_size) {
- m = (void *)e + i;
- if (copy_to_user(userptr + off + i
- + offsetof(struct ipt_entry_match,
- u.user.name),
- m->u.kernel.match->name,
- strlen(m->u.kernel.match->name)+1)
- != 0) {
- ret = -EFAULT;
- goto free_counters;
- }
- }
- t = ipt_get_target(e);
- if (copy_to_user(userptr + off + e->target_offset
- + offsetof(struct ipt_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;
- }
- #ifdef CONFIG_COMPAT
- struct compat_delta {
- struct compat_delta *next;
- unsigned int offset;
- short delta;
- };
- static struct compat_delta *compat_offsets = NULL;
- static int compat_add_offset(unsigned int offset, short delta)
- {
- struct compat_delta *tmp;
- tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
- if (!tmp)
- return -ENOMEM;
- tmp->offset = offset;
- tmp->delta = delta;
- if (compat_offsets) {
- tmp->next = compat_offsets->next;
- compat_offsets->next = tmp;
- } else {
- compat_offsets = tmp;
- tmp->next = NULL;
- }
- return 0;
- }
- static void compat_flush_offsets(void)
- {
- struct compat_delta *tmp, *next;
- if (compat_offsets) {
- for(tmp = compat_offsets; tmp; tmp = next) {
- next = tmp->next;
- kfree(tmp);
- }
- compat_offsets = NULL;
- }
- }
- static short compat_calc_jump(unsigned int offset)
- {
- struct compat_delta *tmp;
- short delta;
- for(tmp = compat_offsets, delta = 0; tmp; tmp = tmp->next)
- if (tmp->offset < offset)
- delta += tmp->delta;
- return delta;
- }
- static void compat_standard_from_user(void *dst, void *src)
- {
- int v = *(compat_int_t *)src;
- if (v > 0)
- v += compat_calc_jump(v);
- memcpy(dst, &v, sizeof(v));
- }
- static int compat_standard_to_user(void __user *dst, void *src)
- {
- compat_int_t cv = *(int *)src;
- if (cv > 0)
- cv -= compat_calc_jump(cv);
- return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
- }
- static inline int
- compat_calc_match(struct ipt_entry_match *m, int * size)
- {
- *size += xt_compat_match_offset(m->u.kernel.match);
- return 0;
- }
- static int compat_calc_entry(struct ipt_entry *e, struct xt_table_info *info,
- void *base, struct xt_table_info *newinfo)
- {
- struct ipt_entry_target *t;
- unsigned int entry_offset;
- int off, i, ret;
- off = 0;
- entry_offset = (void *)e - base;
- IPT_MATCH_ITERATE(e, compat_calc_match, &off);
- t = ipt_get_target(e);
- off += xt_compat_target_offset(t->u.kernel.target);
- newinfo->size -= off;
- ret = compat_add_offset(entry_offset, off);
- if (ret)
- return ret;
- for (i = 0; i< NF_IP_NUMHOOKS; i++) {
- if (info->hook_entry[i] && (e < (struct ipt_entry *)
- (base + info->hook_entry[i])))
- newinfo->hook_entry[i] -= off;
- if (info->underflow[i] && (e < (struct ipt_entry *)
- (base + info->underflow[i])))
- newinfo->underflow[i] -= off;
- }
- return 0;
- }
- static int compat_table_info(struct xt_table_info *info,
- struct xt_table_info *newinfo)
- {
- void *loc_cpu_entry;
- int i;
- if (!newinfo || !info)
- return -EINVAL;
- memset(newinfo, 0, sizeof(struct xt_table_info));
- newinfo->size = info->size;
- newinfo->number = info->number;
- for (i = 0; i < NF_IP_NUMHOOKS; i++) {
- newinfo->hook_entry[i] = info->hook_entry[i];
- newinfo->underflow[i] = info->underflow[i];
- }
- loc_cpu_entry = info->entries[raw_smp_processor_id()];
- return IPT_ENTRY_ITERATE(loc_cpu_entry, info->size,
- compat_calc_entry, info, loc_cpu_entry, newinfo);
- }
- #endif
- static int get_info(void __user *user, int *len, int compat)
- {
- char name[IPT_TABLE_MAXNAMELEN];
- struct xt_table *t;
- int ret;
- if (*len != sizeof(struct ipt_getinfo)) {
- duprintf("length %u != %u\n", *len,
- (unsigned int)sizeof(struct ipt_getinfo));
- return -EINVAL;
- }
- if (copy_from_user(name, user, sizeof(name)) != 0)
- return -EFAULT;
- name[IPT_TABLE_MAXNAMELEN-1] = '\0';
- #ifdef CONFIG_COMPAT
- if (compat)
- xt_compat_lock(AF_INET);
- #endif
- t = try_then_request_module(xt_find_table_lock(AF_INET, name),
- "iptable_%s", name);
- if (t && !IS_ERR(t)) {
- struct ipt_getinfo info;
- struct xt_table_info *private = t->private;
- #ifdef CONFIG_COMPAT
- if (compat) {
- struct xt_table_info tmp;
- ret = compat_table_info(private, &tmp);
- compat_flush_offsets();
- private = &tmp;
- }
- #endif
- 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;
- strcpy(info.name, 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;
- #ifdef CONFIG_COMPAT
- if (compat)
- xt_compat_unlock(AF_INET);
- #endif
- return ret;
- }
- static int
- get_entries(struct ipt_get_entries __user *uptr, int *len)
- {
- int ret;
- struct ipt_get_entries get;
- struct xt_table *t;
- if (*len < sizeof(get)) {
- duprintf("get_entries: %u < %d\n", *len,
- (unsigned int)sizeof(get));
- return -EINVAL;
- }
- if (copy_from_user(&get, uptr, sizeof(get)) != 0)
- return -EFAULT;
- if (*len != sizeof(struct ipt_get_entries) + get.size) {
- duprintf("get_entries: %u != %u\n", *len,
- (unsigned int)(sizeof(struct ipt_get_entries) +
- get.size));
- return -EINVAL;
- }
- t = xt_find_table_lock(AF_INET, get.name);
- if (t && !IS_ERR(t)) {
- struct xt_table_info *private = t->private;
- duprintf("t->private->number = %u\n",
- private->number);
- if (get.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,
- get.size);
- ret = -EINVAL;
- }
- module_put(t->me);
- xt_table_unlock(t);
- } else
- ret = t ? PTR_ERR(t) : -ENOENT;
- return ret;
- }
- static int
- __do_replace(const char *name, unsigned int valid_hooks,
- struct xt_table_info *newinfo, unsigned int num_counters,
- void __user *counters_ptr)
- {
- int ret;
- struct xt_table *t;
- struct xt_table_info *oldinfo;
- struct xt_counters *counters;
- void *loc_cpu_old_entry;
- ret = 0;
- counters = vmalloc(num_counters * sizeof(struct xt_counters));
- if (!counters) {
- ret = -ENOMEM;
- goto out;
- }
- t = try_then_request_module(xt_find_table_lock(AF_INET, name),
- "iptable_%s", name);
- if (!t || IS_ERR(t)) {
- ret = t ? PTR_ERR(t) : -ENOENT;
- goto free_newinfo_counters_untrans;
- }
- /* You lied! */
- if (valid_hooks != t->valid_hooks) {
- duprintf("Valid hook crap: %08X vs %08X\n",
- valid_hooks, t->valid_hooks);
- ret = -EINVAL;
- goto put_module;
- }
- oldinfo = xt_replace_table(t, 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()];
- IPT_ENTRY_ITERATE(loc_cpu_old_entry, oldinfo->size, cleanup_entry,NULL);
- xt_free_table_info(oldinfo);
- if (copy_to_user(counters_ptr, counters,
- sizeof(struct xt_counters) * 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:
- vfree(counters);
- out:
- return ret;
- }
- static int
- do_replace(void __user *user, unsigned int len)
- {
- int ret;
- struct ipt_replace tmp;
- struct xt_table_info *newinfo;
- void *loc_cpu_entry;
- if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
- return -EFAULT;
- /* Hack: Causes ipchains to give correct error msg --RR */
- if (len != sizeof(tmp) + tmp.size)
- return -ENOPROTOOPT;
- /* 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 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;
- }
- 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;
- duprintf("ip_tables: Translated table\n");
- ret = __do_replace(tmp.name, tmp.valid_hooks,
- newinfo, tmp.num_counters,
- tmp.counters);
- if (ret)
- goto free_newinfo_untrans;
- return 0;
- free_newinfo_untrans:
- IPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL);
- 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 ipt_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, int compat)
- {
- unsigned int i;
- struct xt_counters_info tmp;
- struct xt_counters *paddc;
- unsigned int num_counters;
- char *name;
- int size;
- void *ptmp;
- struct xt_table *t;
- struct xt_table_info *private;
- int ret = 0;
- void *loc_cpu_entry;
- #ifdef CONFIG_COMPAT
- struct compat_xt_counters_info compat_tmp;
- if (compat) {
- ptmp = &compat_tmp;
- size = sizeof(struct compat_xt_counters_info);
- } else
- #endif
- {
- ptmp = &tmp;
- size = sizeof(struct xt_counters_info);
- }
- if (copy_from_user(ptmp, user, size) != 0)
- return -EFAULT;
- #ifdef CONFIG_COMPAT
- if (compat) {
- num_counters = compat_tmp.num_counters;
- name = compat_tmp.name;
- } else
- #endif
- {
- num_counters = tmp.num_counters;
- name = tmp.name;
- }
- if (len != size + num_counters * sizeof(struct xt_counters))
- return -EINVAL;
- paddc = vmalloc_node(len - size, numa_node_id());
- if (!paddc)
- return -ENOMEM;
- if (copy_from_user(paddc, user + size, len - size) != 0) {
- ret = -EFAULT;
- goto free;
- }
- t = xt_find_table_lock(AF_INET, 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 != num_counters) {
- ret = -EINVAL;
- goto unlock_up_free;
- }
- i = 0;
- /* Choose the copy that is on our node */
- loc_cpu_entry = private->entries[raw_smp_processor_id()];
- IPT_ENTRY_ITERATE(loc_cpu_entry,
- private->size,
- add_counter_to_entry,
- paddc,
- &i);
- unlock_up_free:
- write_unlock_bh(&t->lock);
- xt_table_unlock(t);
- module_put(t->me);
- free:
- vfree(paddc);
- return ret;
- }
- #ifdef CONFIG_COMPAT
- struct compat_ipt_replace {
- char name[IPT_TABLE_MAXNAMELEN];
- u32 valid_hooks;
- u32 num_entries;
- u32 size;
- u32 hook_entry[NF_IP_NUMHOOKS];
- u32 underflow[NF_IP_NUMHOOKS];
- u32 num_counters;
- compat_uptr_t counters; /* struct ipt_counters * */
- struct compat_ipt_entry entries[0];
- };
- static inline int compat_copy_match_to_user(struct ipt_entry_match *m,
- void __user **dstptr, compat_uint_t *size)
- {
- return xt_compat_match_to_user(m, dstptr, size);
- }
- static int compat_copy_entry_to_user(struct ipt_entry *e,
- void __user **dstptr, compat_uint_t *size)
- {
- struct ipt_entry_target *t;
- struct compat_ipt_entry __user *ce;
- u_int16_t target_offset, next_offset;
- compat_uint_t origsize;
- int ret;
- ret = -EFAULT;
- origsize = *size;
- ce = (struct compat_ipt_entry __user *)*dstptr;
- if (copy_to_user(ce, e, sizeof(struct ipt_entry)))
- goto out;
- *dstptr += sizeof(struct compat_ipt_entry);
- ret = IPT_MATCH_ITERATE(e, compat_copy_match_to_user, dstptr, size);
- target_offset = e->target_offset - (origsize - *size);
- if (ret)
- goto out;
- t = ipt_get_target(e);
- ret = xt_compat_target_to_user(t, dstptr, size);
- if (ret)
- goto out;
- ret = -EFAULT;
- next_offset = e->next_offset - (origsize - *size);
- if (put_user(target_offset, &ce->target_offset))
- goto out;
- if (put_user(next_offset, &ce->next_offset))
- goto out;
- return 0;
- out:
- return ret;
- }
- static inline int
- compat_check_calc_match(struct ipt_entry_match *m,
- const char *name,
- const struct ipt_ip *ip,
- unsigned int hookmask,
- int *size, int *i)
- {
- struct xt_match *match;
- match = try_then_request_module(xt_find_match(AF_INET, m->u.user.name,
- m->u.user.revision),
- "ipt_%s", m->u.user.name);
- if (IS_ERR(match) || !match) {
- duprintf("compat_check_calc_match: `%s' not found\n",
- m->u.user.name);
- return match ? PTR_ERR(match) : -ENOENT;
- }
- m->u.kernel.match = match;
- *size += xt_compat_match_offset(match);
- (*i)++;
- return 0;
- }
- static inline int
- check_compat_entry_size_and_hooks(struct ipt_entry *e,
- struct xt_table_info *newinfo,
- unsigned int *size,
- unsigned char *base,
- unsigned char *limit,
- unsigned int *hook_entries,
- unsigned int *underflows,
- unsigned int *i,
- const char *name)
- {
- struct ipt_entry_target *t;
- struct xt_target *target;
- unsigned int entry_offset;
- int ret, off, h, j;
- duprintf("check_compat_entry_size_and_hooks %p\n", e);
- if ((unsigned long)e % __alignof__(struct compat_ipt_entry) != 0
- || (unsigned char *)e + sizeof(struct compat_ipt_entry) >= limit) {
- duprintf("Bad offset %p, limit = %p\n", e, limit);
- return -EINVAL;
- }
- if (e->next_offset < sizeof(struct compat_ipt_entry) +
- sizeof(struct compat_xt_entry_target)) {
- duprintf("checking: element %p size %u\n",
- e, e->next_offset);
- return -EINVAL;
- }
- ret = check_entry(e, name);
- if (ret)
- return ret;
- off = 0;
- entry_offset = (void *)e - (void *)base;
- j = 0;
- ret = IPT_MATCH_ITERATE(e, compat_check_calc_match, name, &e->ip,
- e->comefrom, &off, &j);
- if (ret != 0)
- goto cleanup_matches;
- t = ipt_get_target(e);
- target = try_then_request_module(xt_find_target(AF_INET,
- t->u.user.name,
- t->u.user.revision),
- "ipt_%s", t->u.user.name);
- if (IS_ERR(target) || !target) {
- duprintf("check_compat_entry_size_and_hooks: `%s' not found\n",
- t->u.user.name);
- ret = target ? PTR_ERR(target) : -ENOENT;
- goto cleanup_matches;
- }
- t->u.kernel.target = target;
- off += xt_compat_target_offset(target);
- *size += off;
- ret = compat_add_offset(entry_offset, off);
- if (ret)
- goto out;
- /* Check hooks & underflows */
- for (h = 0; h < NF_IP_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];
- }
- /* Clear counters and comefrom */
- e->counters = ((struct ipt_counters) { 0, 0 });
- e->comefrom = 0;
- (*i)++;
- return 0;
- out:
- module_put(t->u.kernel.target->me);
- cleanup_matches:
- IPT_MATCH_ITERATE(e, cleanup_match, &j);
- return ret;
- }
- static inline int compat_copy_match_from_user(struct ipt_entry_match *m,
- void **dstptr, compat_uint_t *size, const char *name,
- const struct ipt_ip *ip, unsigned int hookmask)
- {
- xt_compat_match_from_user(m, dstptr, size);
- return 0;
- }
- static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr,
- unsigned int *size, const char *name,
- struct xt_table_info *newinfo, unsigned char *base)
- {
- struct ipt_entry_target *t;
- struct xt_target *target;
- struct ipt_entry *de;
- unsigned int origsize;
- int ret, h;
- ret = 0;
- origsize = *size;
- de = (struct ipt_entry *)*dstptr;
- memcpy(de, e, sizeof(struct ipt_entry));
- *dstptr += sizeof(struct compat_ipt_entry);
- ret = IPT_MATCH_ITERATE(e, compat_copy_match_from_user, dstptr, size,
- name, &de->ip, de->comefrom);
- if (ret)
- return ret;
- de->target_offset = e->target_offset - (origsize - *size);
- t = ipt_get_target(e);
- target = t->u.kernel.target;
- xt_compat_target_from_user(t, dstptr, size);
- de->next_offset = e->next_offset - (origsize - *size);
- for (h = 0; h < NF_IP_NUMHOOKS; h++) {
- if ((unsigned char *)de - base < newinfo->hook_entry[h])
- newinfo->hook_entry[h] -= origsize - *size;
- if ((unsigned char *)de - base < newinfo->underflow[h])
- newinfo->underflow[h] -= origsize - *size;
- }
- return ret;
- }
- static inline int compat_check_entry(struct ipt_entry *e, const char *name)
- {
- int ret;
- ret = IPT_MATCH_ITERATE(e, check_match, name, &e->ip, e->comefrom);
- if (ret)
- return ret;
- return check_target(e, name);
- }
- static int
- translate_compat_table(const char *name,
- unsigned int valid_hooks,
- struct xt_table_info **pinfo,
- void **pentry0,
- unsigned int total_size,
- unsigned int number,
- unsigned int *hook_entries,
- unsigned int *underflows)
- {
- unsigned int i, j;
- struct xt_table_info *newinfo, *info;
- void *pos, *entry0, *entry1;
- unsigned int size;
- int ret;
- info = *pinfo;
- entry0 = *pentry0;
- size = total_size;
- info->number = number;
- /* Init all hooks to impossible value. */
- for (i = 0; i < NF_IP_NUMHOOKS; i++) {
- info->hook_entry[i] = 0xFFFFFFFF;
- info->underflow[i] = 0xFFFFFFFF;
- }
- duprintf("translate_compat_table: size %u\n", info->size);
- j = 0;
- xt_compat_lock(AF_INET);
- /* Walk through entries, checking offsets. */
- ret = IPT_ENTRY_ITERATE(entry0, total_size,
- check_compat_entry_size_and_hooks,
- info, &size, entry0,
- entry0 + total_size,
- hook_entries, underflows, &j, name);
- if (ret != 0)
- goto out_unlock;
- ret = -EINVAL;
- if (j != number) {
- duprintf("translate_compat_table: %u not %u entries\n",
- j, number);
- goto out_unlock;
- }
- /* Check hooks all assigned */
- for (i = 0; i < NF_IP_NUMHOOKS; i++) {
- /* Only hooks which are valid */
- if (!(valid_hooks & (1 << i)))
- continue;
- if (info->hook_entry[i] == 0xFFFFFFFF) {
- duprintf("Invalid hook entry %u %u\n",
- i, hook_entries[i]);
- goto out_unlock;
- }
- if (info->underflow[i] == 0xFFFFFFFF) {
- duprintf("Invalid underflow %u %u\n",
- i, underflows[i]);
- goto out_unlock;
- }
- }
- ret = -ENOMEM;
- newinfo = xt_alloc_table_info(size);
- if (!newinfo)
- goto out_unlock;
- newinfo->number = number;
- for (i = 0; i < NF_IP_NUMHOOKS; i++) {
- newinfo->hook_entry[i] = info->hook_entry[i];
- newinfo->underflow[i] = info->underflow[i];
- }
- entry1 = newinfo->entries[raw_smp_processor_id()];
- pos = entry1;
- size = total_size;
- ret = IPT_ENTRY_ITERATE(entry0, total_size,
- compat_copy_entry_from_user, &pos, &size,
- name, newinfo, entry1);
- compat_flush_offsets();
- xt_compat_unlock(AF_INET);
- if (ret)
- goto free_newinfo;
- ret = -ELOOP;
- if (!mark_source_chains(newinfo, valid_hooks, entry1))
- goto free_newinfo;
- ret = IPT_ENTRY_ITERATE(entry1, newinfo->size, compat_check_entry,
- name);
- if (ret)
- goto free_newinfo;
- /* And one copy for every other CPU */
- for_each_possible_cpu(i)
- if (newinfo->entries[i] && newinfo->entries[i] != entry1)
- memcpy(newinfo->entries[i], entry1, newinfo->size);
- *pinfo = newinfo;
- *pentry0 = entry1;
- xt_free_table_info(info);
- return 0;
- free_newinfo:
- xt_free_table_info(newinfo);
- out:
- IPT_ENTRY_ITERATE(entry0, total_size, cleanup_entry, &j);
- return ret;
- out_unlock:
- compat_flush_offsets();
- xt_compat_unlock(AF_INET);
- goto out;
- }
- static int
- compat_do_replace(void __user *user, unsigned int len)
- {
- int ret;
- struct compat_ipt_replace tmp;
- struct xt_table_info *newinfo;
- void *loc_cpu_entry;
- if (copy_from_user(&tmp, user, sizeof(tmp)) != 0)
- return -EFAULT;
- /* Hack: Causes ipchains to give correct error msg --RR */
- if (len != sizeof(tmp) + tmp.size)
- return -ENOPROTOOPT;
- /* 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 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;
- }
- ret = translate_compat_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;
- duprintf("compat_do_replace: Translated table\n");
- ret = __do_replace(tmp.name, tmp.valid_hooks,
- newinfo, tmp.num_counters,
- compat_ptr(tmp.counters));
- if (ret)
- goto free_newinfo_untrans;
- return 0;
- free_newinfo_untrans:
- IPT_ENTRY_ITERATE(loc_cpu_entry, newinfo->size, cleanup_entry,NULL);
- free_newinfo:
- xt_free_table_info(newinfo);
- return ret;
- }
- static int
- compat_do_ipt_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 IPT_SO_SET_REPLACE:
- ret = compat_do_replace(user, len);
- break;
- case IPT_SO_SET_ADD_COUNTERS:
- ret = do_add_counters(user, len, 1);
- break;
- default:
- duprintf("do_ipt_set_ctl: unknown request %i\n", cmd);
- ret = -EINVAL;
- }
- return ret;
- }
- struct compat_ipt_get_entries
- {
- char name[IPT_TABLE_MAXNAMELEN];
- compat_uint_t size;
- struct compat_ipt_entry entrytable[0];
- };
- static int compat_copy_entries_to_user(unsigned int total_size,
- struct xt_table *table, void __user *userptr)
- {
- unsigned int off, num;
- struct compat_ipt_entry e;
- struct xt_counters *counters;
- struct xt_table_info *private = table->private;
- void __user *pos;
- unsigned int size;
- int ret = 0;
- void *loc_cpu_entry;
- counters = alloc_counters(table);
- if (IS_ERR(counters))
- return PTR_ERR(counters);
- /* choose the copy that is on our node/cpu, ...
- * This choice is lazy (because current thread is
- * allowed to migrate to another cpu)
- */
- loc_cpu_entry = private->entries[raw_smp_processor_id()];
- pos = userptr;
- size = total_size;
- ret = IPT_ENTRY_ITERATE(loc_cpu_entry, total_size,
- compat_copy_entry_to_user, &pos, &size);
- if (ret)
- goto free_counters;
- /* ... then go back and fix counters and names */
- for (off = 0, num = 0; off < size; off += e.next_offset, num++) {
- unsigned int i;
- struct ipt_entry_match m;
- struct ipt_entry_target t;
- ret = -EFAULT;
- if (copy_from_user(&e, userptr + off,
- sizeof(struct compat_ipt_entry)))
- goto free_counters;
- if (copy_to_user(userptr + off +
- offsetof(struct compat_ipt_entry, counters),
- &counters[num], sizeof(counters[num])))
- goto free_counters;
- for (i = sizeof(struct compat_ipt_entry);
- i < e.target_offset; i += m.u.match_size) {
- if (copy_from_user(&m, userptr + off + i,
- sizeof(struct ipt_entry_match)))
- goto free_counters;
- if (copy_to_user(userptr + off + i +
- offsetof(struct ipt_entry_match, u.user.name),
- m.u.kernel.match->name,
- strlen(m.u.kernel.match->name) + 1))
- goto free_counters;
- }
- if (copy_from_user(&t, userptr + off + e.target_offset,
- sizeof(struct ipt_entry_target)))
- goto free_counters;
- if (copy_to_user(userptr + off + e.target_offset +
- offsetof(struct ipt_entry_target, u.user.name),
- t.u.kernel.target->name,
- strlen(t.u.kernel.target->name) + 1))
- goto free_counters;
- }
- ret = 0;
- free_counters:
- vfree(counters);
- return ret;
- }
- static int
- compat_get_entries(struct compat_ipt_get_entries __user *uptr, int *len)
- {
- int ret;
- struct compat_ipt_get_entries get;
- struct xt_table *t;
- if (*len < sizeof(get)) {
- duprintf("compat_get_entries: %u < %u\n",
- *len, (unsigned int)sizeof(get));
- return -EINVAL;
- }
- if (copy_from_user(&get, uptr, sizeof(get)) != 0)
- return -EFAULT;
- if (*len != sizeof(struct compat_ipt_get_entries) + get.size) {
- duprintf("compat_get_entries: %u != %u\n", *len,
- (unsigned int)(sizeof(struct compat_ipt_get_entries) +
- get.size));
- return -EINVAL;
- }
- xt_compat_lock(AF_INET);
- t = xt_find_table_lock(AF_INET, get.name);
- if (t && !IS_ERR(t)) {
- struct xt_table_info *private = t->private;
- struct xt_table_info info;
- duprintf("t->private->number = %u\n",
- private->number);
- ret = compat_table_info(private, &info);
- if (!ret && get.size == info.size) {
- ret = compat_copy_entries_to_user(private->size,
- t, uptr->entrytable);
- } else if (!ret) {
- duprintf("compat_get_entries: I've got %u not %u!\n",
- private->size,
- get.size);
- ret = -EINVAL;
- }
- compat_flush_offsets();
- module_put(t->me);
- xt_table_unlock(t);
- } else
- ret = t ? PTR_ERR(t) : -ENOENT;
- xt_compat_unlock(AF_INET);
- return ret;
- }
- static int do_ipt_get_ctl(struct sock *, int, void __user *, int *);
- static int
- compat_do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
- {
- int ret;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
- switch (cmd) {
- case IPT_SO_GET_INFO:
- ret = get_info(user, len, 1);
- break;
- case IPT_SO_GET_ENTRIES:
- ret = compat_get_entries(user, len);
- break;
- default:
- ret = do_ipt_get_ctl(sk, cmd, user, len);
- }
- return ret;
- }
- #endif
- static int
- do_ipt_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 IPT_SO_SET_REPLACE:
- ret = do_replace(user, len);
- break;
- case IPT_SO_SET_ADD_COUNTERS:
- ret = do_add_counters(user, len, 0);
- break;
- default:
- duprintf("do_ipt_set_ctl: unknown request %i\n", cmd);
- ret = -EINVAL;
- }
- return ret;
- }
- static int
- do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
- {
- int ret;
- if (!capable(CAP_NET_ADMIN))
- return -EPERM;
- switch (cmd) {
- case IPT_SO_GET_INFO:
- ret = get_info(user, len, 0);
- break;
- case IPT_SO_GET_ENTRIES:
- ret = get_entries(user, len);
- break;
- case IPT_SO_GET_REVISION_MATCH:
- case IPT_SO_GET_REVISION_TARGET: {
- struct ipt_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 == IPT_SO_GET_REVISION_TARGET)
- target = 1;
- else
- target = 0;
- try_then_request_module(xt_find_revision(AF_INET, rev.name,
- rev.revision,
- target, &ret),
- "ipt_%s", rev.name);
- break;
- }
- default:
- duprintf("do_ipt_get_ctl: unknown request %i\n", cmd);
- ret = -EINVAL;
- }
- return ret;
- }
- int ipt_register_table(struct xt_table *table, const struct ipt_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
- * but dont care of preemption
- */
- 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 ipt_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()];
- IPT_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
- icmp_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 ((test_type == 0xFF) || (type == test_type && code >= min_code && code <= max_code))
- ^ invert;
- }
- static int
- icmp_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,
- int *hotdrop)
- {
- struct icmphdr _icmph, *ic;
- const struct ipt_icmp *icmpinfo = matchinfo;
- /* Must not be a fragment. */
- if (offset)
- return 0;
- ic = skb_header_pointer(skb, protoff, sizeof(_icmph), &_icmph);
- 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 = 1;
- return 0;
- }
- return icmp_type_code_match(icmpinfo->type,
- icmpinfo->code[0],
- icmpinfo->code[1],
- ic->type, ic->code,
- !!(icmpinfo->invflags&IPT_ICMP_INV));
- }
- /* Called when user tries to insert an entry of this type. */
- static int
- icmp_checkentry(const char *tablename,
- const void *info,
- const struct xt_match *match,
- void *matchinfo,
- unsigned int hook_mask)
- {
- const struct ipt_icmp *icmpinfo = matchinfo;
- /* Must specify no unknown invflags */
- return !(icmpinfo->invflags & ~IPT_ICMP_INV);
- }
- /* The built-in targets: standard (NULL) and error. */
- static struct xt_target ipt_standard_target = {
- .name = IPT_STANDARD_TARGET,
- .targetsize = sizeof(int),
- .family = AF_INET,
- #ifdef CONFIG_COMPAT
- .compatsize = sizeof(compat_int_t),
- .compat_from_user = compat_standard_from_user,
- .compat_to_user = compat_standard_to_user,
- #endif
- };
- static struct xt_target ipt_error_target = {
- .name = IPT_ERROR_TARGET,
- .target = ipt_error,
- .targetsize = IPT_FUNCTION_MAXNAMELEN,
- .family = AF_INET,
- };
- static struct nf_sockopt_ops ipt_sockopts = {
- .pf = PF_INET,
- .set_optmin = IPT_BASE_CTL,
- .set_optmax = IPT_SO_SET_MAX+1,
- .set = do_ipt_set_ctl,
- #ifdef CONFIG_COMPAT
- .compat_set = compat_do_ipt_set_ctl,
- #endif
- .get_optmin = IPT_BASE_CTL,
- .get_optmax = IPT_SO_GET_MAX+1,
- .get = do_ipt_get_ctl,
- #ifdef CONFIG_COMPAT
- .compat_get = compat_do_ipt_get_ctl,
- #endif
- };
- static struct xt_match icmp_matchstruct = {
- .name = "icmp",
- .match = icmp_match,
- .matchsize = sizeof(struct ipt_icmp),
- .proto = IPPROTO_ICMP,
- .family = AF_INET,
- .checkentry = icmp_checkentry,
- };
- static int __init ip_tables_init(void)
- {
- int ret;
- ret = xt_proto_init(AF_INET);
- if (ret < 0)
- goto err1;
- /* Noone else will be downing sem now, so we won't sleep */
- ret = xt_register_target(&ipt_standard_target);
- if (ret < 0)
- goto err2;
- ret = xt_register_target(&ipt_error_target);
- if (ret < 0)
- goto err3;
- ret = xt_register_match(&icmp_matchstruct);
- if (ret < 0)
- goto err4;
- /* Register setsockopt */
- ret = nf_register_sockopt(&ipt_sockopts);
- if (ret < 0)
- goto err5;
- printk("ip_tables: (C) 2000-2006 Netfilter Core Team\n");
- return 0;
- err5:
- xt_unregister_match(&icmp_matchstruct);
- err4:
- xt_unregister_target(&ipt_error_target);
- err3:
- xt_unregister_target(&ipt_standard_target);
- err2:
- xt_proto_fini(AF_INET);
- err1:
- return ret;
- }
- static void __exit ip_tables_fini(void)
- {
- nf_unregister_sockopt(&ipt_sockopts);
- xt_unregister_match(&icmp_matchstruct);
- xt_unregister_target(&ipt_error_target);
- xt_unregister_target(&ipt_standard_target);
- xt_proto_fini(AF_INET);
- }
- EXPORT_SYMBOL(ipt_register_table);
- EXPORT_SYMBOL(ipt_unregister_table);
- EXPORT_SYMBOL(ipt_do_table);
- module_init(ip_tables_init);
- module_exit(ip_tables_fini);
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