| /* |
| * ebtables |
| * |
| * Author: |
| * Bart De Schuymer <bdschuym@pandora.be> |
| * |
| * ebtables.c,v 2.0, July, 2002 |
| * |
| * This code is stongly inspired on the iptables code which is |
| * Copyright (C) 1999 Paul `Rusty' Russell & Michael J. Neuling |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| /* used for print_string */ |
| #include <linux/sched.h> |
| #include <linux/tty.h> |
| |
| #include <linux/kmod.h> |
| #include <linux/module.h> |
| #include <linux/vmalloc.h> |
| #include <linux/netfilter_bridge/ebtables.h> |
| #include <linux/spinlock.h> |
| #include <asm/uaccess.h> |
| #include <linux/smp.h> |
| #include <linux/cpumask.h> |
| #include <net/sock.h> |
| /* needed for logical [in,out]-dev filtering */ |
| #include "../br_private.h" |
| |
| /* list_named_find */ |
| #define ASSERT_READ_LOCK(x) |
| #define ASSERT_WRITE_LOCK(x) |
| #include <linux/netfilter_ipv4/listhelp.h> |
| |
| #if 0 |
| /* use this for remote debugging |
| * Copyright (C) 1998 by Ori Pomerantz |
| * Print the string to the appropriate tty, the one |
| * the current task uses |
| */ |
| static void print_string(char *str) |
| { |
| struct tty_struct *my_tty; |
| |
| /* The tty for the current task */ |
| my_tty = current->signal->tty; |
| if (my_tty != NULL) { |
| my_tty->driver->write(my_tty, 0, str, strlen(str)); |
| my_tty->driver->write(my_tty, 0, "\015\012", 2); |
| } |
| } |
| |
| #define BUGPRINT(args) print_string(args); |
| #else |
| #define BUGPRINT(format, args...) printk("kernel msg: ebtables bug: please "\ |
| "report to author: "format, ## args) |
| /* #define BUGPRINT(format, args...) */ |
| #endif |
| #define MEMPRINT(format, args...) printk("kernel msg: ebtables "\ |
| ": out of memory: "format, ## args) |
| /* #define MEMPRINT(format, args...) */ |
| |
| |
| |
| /* |
| * Each cpu has its own set of counters, so there is no need for write_lock in |
| * the softirq |
| * For reading or updating the counters, the user context needs to |
| * get a write_lock |
| */ |
| |
| /* The size of each set of counters is altered to get cache alignment */ |
| #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1)) |
| #define COUNTER_OFFSET(n) (SMP_ALIGN(n * sizeof(struct ebt_counter))) |
| #define COUNTER_BASE(c, n, cpu) ((struct ebt_counter *)(((char *)c) + \ |
| COUNTER_OFFSET(n) * cpu)) |
| |
| |
| |
| static DECLARE_MUTEX(ebt_mutex); |
| static LIST_HEAD(ebt_tables); |
| static LIST_HEAD(ebt_targets); |
| static LIST_HEAD(ebt_matches); |
| static LIST_HEAD(ebt_watchers); |
| |
| static struct ebt_target ebt_standard_target = |
| { {NULL, NULL}, EBT_STANDARD_TARGET, NULL, NULL, NULL, NULL}; |
| |
| static inline int ebt_do_watcher (struct ebt_entry_watcher *w, |
| const struct sk_buff *skb, unsigned int hooknr, const struct net_device *in, |
| const struct net_device *out) |
| { |
| w->u.watcher->watcher(skb, hooknr, in, out, w->data, |
| w->watcher_size); |
| /* watchers don't give a verdict */ |
| return 0; |
| } |
| |
| static inline int ebt_do_match (struct ebt_entry_match *m, |
| const struct sk_buff *skb, const struct net_device *in, |
| const struct net_device *out) |
| { |
| return m->u.match->match(skb, in, out, m->data, |
| m->match_size); |
| } |
| |
| static inline int ebt_dev_check(char *entry, const struct net_device *device) |
| { |
| int i = 0; |
| char *devname = device->name; |
| |
| if (*entry == '\0') |
| return 0; |
| if (!device) |
| return 1; |
| /* 1 is the wildcard token */ |
| while (entry[i] != '\0' && entry[i] != 1 && entry[i] == devname[i]) |
| i++; |
| return (devname[i] != entry[i] && entry[i] != 1); |
| } |
| |
| #define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg)) |
| /* process standard matches */ |
| static inline int ebt_basic_match(struct ebt_entry *e, struct ethhdr *h, |
| const struct net_device *in, const struct net_device *out) |
| { |
| int verdict, i; |
| |
| if (e->bitmask & EBT_802_3) { |
| if (FWINV2(ntohs(h->h_proto) >= 1536, EBT_IPROTO)) |
| return 1; |
| } else if (!(e->bitmask & EBT_NOPROTO) && |
| FWINV2(e->ethproto != h->h_proto, EBT_IPROTO)) |
| return 1; |
| |
| if (FWINV2(ebt_dev_check(e->in, in), EBT_IIN)) |
| return 1; |
| if (FWINV2(ebt_dev_check(e->out, out), EBT_IOUT)) |
| return 1; |
| if ((!in || !in->br_port) ? 0 : FWINV2(ebt_dev_check( |
| e->logical_in, in->br_port->br->dev), EBT_ILOGICALIN)) |
| return 1; |
| if ((!out || !out->br_port) ? 0 : FWINV2(ebt_dev_check( |
| e->logical_out, out->br_port->br->dev), EBT_ILOGICALOUT)) |
| return 1; |
| |
| if (e->bitmask & EBT_SOURCEMAC) { |
| verdict = 0; |
| for (i = 0; i < 6; i++) |
| verdict |= (h->h_source[i] ^ e->sourcemac[i]) & |
| e->sourcemsk[i]; |
| if (FWINV2(verdict != 0, EBT_ISOURCE) ) |
| return 1; |
| } |
| if (e->bitmask & EBT_DESTMAC) { |
| verdict = 0; |
| for (i = 0; i < 6; i++) |
| verdict |= (h->h_dest[i] ^ e->destmac[i]) & |
| e->destmsk[i]; |
| if (FWINV2(verdict != 0, EBT_IDEST) ) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* Do some firewalling */ |
| unsigned int ebt_do_table (unsigned int hook, struct sk_buff **pskb, |
| const struct net_device *in, const struct net_device *out, |
| struct ebt_table *table) |
| { |
| int i, nentries; |
| struct ebt_entry *point; |
| struct ebt_counter *counter_base, *cb_base; |
| struct ebt_entry_target *t; |
| int verdict, sp = 0; |
| struct ebt_chainstack *cs; |
| struct ebt_entries *chaininfo; |
| char *base; |
| struct ebt_table_info *private; |
| |
| read_lock_bh(&table->lock); |
| private = table->private; |
| cb_base = COUNTER_BASE(private->counters, private->nentries, |
| smp_processor_id()); |
| if (private->chainstack) |
| cs = private->chainstack[smp_processor_id()]; |
| else |
| cs = NULL; |
| chaininfo = private->hook_entry[hook]; |
| nentries = private->hook_entry[hook]->nentries; |
| point = (struct ebt_entry *)(private->hook_entry[hook]->data); |
| counter_base = cb_base + private->hook_entry[hook]->counter_offset; |
| /* base for chain jumps */ |
| base = private->entries; |
| i = 0; |
| while (i < nentries) { |
| if (ebt_basic_match(point, eth_hdr(*pskb), in, out)) |
| goto letscontinue; |
| |
| if (EBT_MATCH_ITERATE(point, ebt_do_match, *pskb, in, out) != 0) |
| goto letscontinue; |
| |
| /* increase counter */ |
| (*(counter_base + i)).pcnt++; |
| (*(counter_base + i)).bcnt+=(**pskb).len; |
| |
| /* these should only watch: not modify, nor tell us |
| what to do with the packet */ |
| EBT_WATCHER_ITERATE(point, ebt_do_watcher, *pskb, hook, in, |
| out); |
| |
| t = (struct ebt_entry_target *) |
| (((char *)point) + point->target_offset); |
| /* standard target */ |
| if (!t->u.target->target) |
| verdict = ((struct ebt_standard_target *)t)->verdict; |
| else |
| verdict = t->u.target->target(pskb, hook, |
| in, out, t->data, t->target_size); |
| if (verdict == EBT_ACCEPT) { |
| read_unlock_bh(&table->lock); |
| return NF_ACCEPT; |
| } |
| if (verdict == EBT_DROP) { |
| read_unlock_bh(&table->lock); |
| return NF_DROP; |
| } |
| if (verdict == EBT_RETURN) { |
| letsreturn: |
| #ifdef CONFIG_NETFILTER_DEBUG |
| if (sp == 0) { |
| BUGPRINT("RETURN on base chain"); |
| /* act like this is EBT_CONTINUE */ |
| goto letscontinue; |
| } |
| #endif |
| sp--; |
| /* put all the local variables right */ |
| i = cs[sp].n; |
| chaininfo = cs[sp].chaininfo; |
| nentries = chaininfo->nentries; |
| point = cs[sp].e; |
| counter_base = cb_base + |
| chaininfo->counter_offset; |
| continue; |
| } |
| if (verdict == EBT_CONTINUE) |
| goto letscontinue; |
| #ifdef CONFIG_NETFILTER_DEBUG |
| if (verdict < 0) { |
| BUGPRINT("bogus standard verdict\n"); |
| read_unlock_bh(&table->lock); |
| return NF_DROP; |
| } |
| #endif |
| /* jump to a udc */ |
| cs[sp].n = i + 1; |
| cs[sp].chaininfo = chaininfo; |
| cs[sp].e = (struct ebt_entry *) |
| (((char *)point) + point->next_offset); |
| i = 0; |
| chaininfo = (struct ebt_entries *) (base + verdict); |
| #ifdef CONFIG_NETFILTER_DEBUG |
| if (chaininfo->distinguisher) { |
| BUGPRINT("jump to non-chain\n"); |
| read_unlock_bh(&table->lock); |
| return NF_DROP; |
| } |
| #endif |
| nentries = chaininfo->nentries; |
| point = (struct ebt_entry *)chaininfo->data; |
| counter_base = cb_base + chaininfo->counter_offset; |
| sp++; |
| continue; |
| letscontinue: |
| point = (struct ebt_entry *) |
| (((char *)point) + point->next_offset); |
| i++; |
| } |
| |
| /* I actually like this :) */ |
| if (chaininfo->policy == EBT_RETURN) |
| goto letsreturn; |
| if (chaininfo->policy == EBT_ACCEPT) { |
| read_unlock_bh(&table->lock); |
| return NF_ACCEPT; |
| } |
| read_unlock_bh(&table->lock); |
| return NF_DROP; |
| } |
| |
| /* If it succeeds, returns element and locks mutex */ |
| static inline void * |
| find_inlist_lock_noload(struct list_head *head, const char *name, int *error, |
| struct semaphore *mutex) |
| { |
| void *ret; |
| |
| *error = down_interruptible(mutex); |
| if (*error != 0) |
| return NULL; |
| |
| ret = list_named_find(head, name); |
| if (!ret) { |
| *error = -ENOENT; |
| up(mutex); |
| } |
| return ret; |
| } |
| |
| #ifndef CONFIG_KMOD |
| #define find_inlist_lock(h,n,p,e,m) find_inlist_lock_noload((h),(n),(e),(m)) |
| #else |
| static void * |
| find_inlist_lock(struct list_head *head, const char *name, const char *prefix, |
| int *error, struct semaphore *mutex) |
| { |
| void *ret; |
| |
| ret = find_inlist_lock_noload(head, name, error, mutex); |
| if (!ret) { |
| request_module("%s%s", prefix, name); |
| ret = find_inlist_lock_noload(head, name, error, mutex); |
| } |
| return ret; |
| } |
| #endif |
| |
| static inline struct ebt_table * |
| find_table_lock(const char *name, int *error, struct semaphore *mutex) |
| { |
| return find_inlist_lock(&ebt_tables, name, "ebtable_", error, mutex); |
| } |
| |
| static inline struct ebt_match * |
| find_match_lock(const char *name, int *error, struct semaphore *mutex) |
| { |
| return find_inlist_lock(&ebt_matches, name, "ebt_", error, mutex); |
| } |
| |
| static inline struct ebt_watcher * |
| find_watcher_lock(const char *name, int *error, struct semaphore *mutex) |
| { |
| return find_inlist_lock(&ebt_watchers, name, "ebt_", error, mutex); |
| } |
| |
| static inline struct ebt_target * |
| find_target_lock(const char *name, int *error, struct semaphore *mutex) |
| { |
| return find_inlist_lock(&ebt_targets, name, "ebt_", error, mutex); |
| } |
| |
| static inline int |
| ebt_check_match(struct ebt_entry_match *m, struct ebt_entry *e, |
| const char *name, unsigned int hookmask, unsigned int *cnt) |
| { |
| struct ebt_match *match; |
| int ret; |
| |
| if (((char *)m) + m->match_size + sizeof(struct ebt_entry_match) > |
| ((char *)e) + e->watchers_offset) |
| return -EINVAL; |
| match = find_match_lock(m->u.name, &ret, &ebt_mutex); |
| if (!match) |
| return ret; |
| m->u.match = match; |
| if (!try_module_get(match->me)) { |
| up(&ebt_mutex); |
| return -ENOENT; |
| } |
| up(&ebt_mutex); |
| if (match->check && |
| match->check(name, hookmask, e, m->data, m->match_size) != 0) { |
| BUGPRINT("match->check failed\n"); |
| module_put(match->me); |
| return -EINVAL; |
| } |
| (*cnt)++; |
| return 0; |
| } |
| |
| static inline int |
| ebt_check_watcher(struct ebt_entry_watcher *w, struct ebt_entry *e, |
| const char *name, unsigned int hookmask, unsigned int *cnt) |
| { |
| struct ebt_watcher *watcher; |
| int ret; |
| |
| if (((char *)w) + w->watcher_size + sizeof(struct ebt_entry_watcher) > |
| ((char *)e) + e->target_offset) |
| return -EINVAL; |
| watcher = find_watcher_lock(w->u.name, &ret, &ebt_mutex); |
| if (!watcher) |
| return ret; |
| w->u.watcher = watcher; |
| if (!try_module_get(watcher->me)) { |
| up(&ebt_mutex); |
| return -ENOENT; |
| } |
| up(&ebt_mutex); |
| if (watcher->check && |
| watcher->check(name, hookmask, e, w->data, w->watcher_size) != 0) { |
| BUGPRINT("watcher->check failed\n"); |
| module_put(watcher->me); |
| return -EINVAL; |
| } |
| (*cnt)++; |
| return 0; |
| } |
| |
| /* |
| * this one is very careful, as it is the first function |
| * to parse the userspace data |
| */ |
| static inline int |
| ebt_check_entry_size_and_hooks(struct ebt_entry *e, |
| struct ebt_table_info *newinfo, char *base, char *limit, |
| struct ebt_entries **hook_entries, unsigned int *n, unsigned int *cnt, |
| unsigned int *totalcnt, unsigned int *udc_cnt, unsigned int valid_hooks) |
| { |
| int i; |
| |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| if ((valid_hooks & (1 << i)) == 0) |
| continue; |
| if ( (char *)hook_entries[i] - base == |
| (char *)e - newinfo->entries) |
| break; |
| } |
| /* beginning of a new chain |
| if i == NF_BR_NUMHOOKS it must be a user defined chain */ |
| if (i != NF_BR_NUMHOOKS || !(e->bitmask & EBT_ENTRY_OR_ENTRIES)) { |
| if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) != 0) { |
| /* we make userspace set this right, |
| so there is no misunderstanding */ |
| BUGPRINT("EBT_ENTRY_OR_ENTRIES shouldn't be set " |
| "in distinguisher\n"); |
| return -EINVAL; |
| } |
| /* this checks if the previous chain has as many entries |
| as it said it has */ |
| if (*n != *cnt) { |
| BUGPRINT("nentries does not equal the nr of entries " |
| "in the chain\n"); |
| return -EINVAL; |
| } |
| /* before we look at the struct, be sure it is not too big */ |
| if ((char *)hook_entries[i] + sizeof(struct ebt_entries) |
| > limit) { |
| BUGPRINT("entries_size too small\n"); |
| return -EINVAL; |
| } |
| if (((struct ebt_entries *)e)->policy != EBT_DROP && |
| ((struct ebt_entries *)e)->policy != EBT_ACCEPT) { |
| /* only RETURN from udc */ |
| if (i != NF_BR_NUMHOOKS || |
| ((struct ebt_entries *)e)->policy != EBT_RETURN) { |
| BUGPRINT("bad policy\n"); |
| return -EINVAL; |
| } |
| } |
| if (i == NF_BR_NUMHOOKS) /* it's a user defined chain */ |
| (*udc_cnt)++; |
| else |
| newinfo->hook_entry[i] = (struct ebt_entries *)e; |
| if (((struct ebt_entries *)e)->counter_offset != *totalcnt) { |
| BUGPRINT("counter_offset != totalcnt"); |
| return -EINVAL; |
| } |
| *n = ((struct ebt_entries *)e)->nentries; |
| *cnt = 0; |
| return 0; |
| } |
| /* a plain old entry, heh */ |
| if (sizeof(struct ebt_entry) > e->watchers_offset || |
| e->watchers_offset > e->target_offset || |
| e->target_offset >= e->next_offset) { |
| BUGPRINT("entry offsets not in right order\n"); |
| return -EINVAL; |
| } |
| /* this is not checked anywhere else */ |
| if (e->next_offset - e->target_offset < sizeof(struct ebt_entry_target)) { |
| BUGPRINT("target size too small\n"); |
| return -EINVAL; |
| } |
| |
| (*cnt)++; |
| (*totalcnt)++; |
| return 0; |
| } |
| |
| struct ebt_cl_stack |
| { |
| struct ebt_chainstack cs; |
| int from; |
| unsigned int hookmask; |
| }; |
| |
| /* |
| * we need these positions to check that the jumps to a different part of the |
| * entries is a jump to the beginning of a new chain. |
| */ |
| static inline int |
| ebt_get_udc_positions(struct ebt_entry *e, struct ebt_table_info *newinfo, |
| struct ebt_entries **hook_entries, unsigned int *n, unsigned int valid_hooks, |
| struct ebt_cl_stack *udc) |
| { |
| int i; |
| |
| /* we're only interested in chain starts */ |
| if (e->bitmask & EBT_ENTRY_OR_ENTRIES) |
| return 0; |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| if ((valid_hooks & (1 << i)) == 0) |
| continue; |
| if (newinfo->hook_entry[i] == (struct ebt_entries *)e) |
| break; |
| } |
| /* only care about udc */ |
| if (i != NF_BR_NUMHOOKS) |
| return 0; |
| |
| udc[*n].cs.chaininfo = (struct ebt_entries *)e; |
| /* these initialisations are depended on later in check_chainloops() */ |
| udc[*n].cs.n = 0; |
| udc[*n].hookmask = 0; |
| |
| (*n)++; |
| return 0; |
| } |
| |
| static inline int |
| ebt_cleanup_match(struct ebt_entry_match *m, unsigned int *i) |
| { |
| if (i && (*i)-- == 0) |
| return 1; |
| if (m->u.match->destroy) |
| m->u.match->destroy(m->data, m->match_size); |
| module_put(m->u.match->me); |
| |
| return 0; |
| } |
| |
| static inline int |
| ebt_cleanup_watcher(struct ebt_entry_watcher *w, unsigned int *i) |
| { |
| if (i && (*i)-- == 0) |
| return 1; |
| if (w->u.watcher->destroy) |
| w->u.watcher->destroy(w->data, w->watcher_size); |
| module_put(w->u.watcher->me); |
| |
| return 0; |
| } |
| |
| static inline int |
| ebt_cleanup_entry(struct ebt_entry *e, unsigned int *cnt) |
| { |
| struct ebt_entry_target *t; |
| |
| if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0) |
| return 0; |
| /* we're done */ |
| if (cnt && (*cnt)-- == 0) |
| return 1; |
| EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, NULL); |
| EBT_MATCH_ITERATE(e, ebt_cleanup_match, NULL); |
| t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| if (t->u.target->destroy) |
| t->u.target->destroy(t->data, t->target_size); |
| module_put(t->u.target->me); |
| |
| return 0; |
| } |
| |
| static inline int |
| ebt_check_entry(struct ebt_entry *e, struct ebt_table_info *newinfo, |
| const char *name, unsigned int *cnt, unsigned int valid_hooks, |
| struct ebt_cl_stack *cl_s, unsigned int udc_cnt) |
| { |
| struct ebt_entry_target *t; |
| struct ebt_target *target; |
| unsigned int i, j, hook = 0, hookmask = 0; |
| int ret; |
| |
| /* don't mess with the struct ebt_entries */ |
| if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0) |
| return 0; |
| |
| if (e->bitmask & ~EBT_F_MASK) { |
| BUGPRINT("Unknown flag for bitmask\n"); |
| return -EINVAL; |
| } |
| if (e->invflags & ~EBT_INV_MASK) { |
| BUGPRINT("Unknown flag for inv bitmask\n"); |
| return -EINVAL; |
| } |
| if ( (e->bitmask & EBT_NOPROTO) && (e->bitmask & EBT_802_3) ) { |
| BUGPRINT("NOPROTO & 802_3 not allowed\n"); |
| return -EINVAL; |
| } |
| /* what hook do we belong to? */ |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| if ((valid_hooks & (1 << i)) == 0) |
| continue; |
| if ((char *)newinfo->hook_entry[i] < (char *)e) |
| hook = i; |
| else |
| break; |
| } |
| /* (1 << NF_BR_NUMHOOKS) tells the check functions the rule is on |
| a base chain */ |
| if (i < NF_BR_NUMHOOKS) |
| hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); |
| else { |
| for (i = 0; i < udc_cnt; i++) |
| if ((char *)(cl_s[i].cs.chaininfo) > (char *)e) |
| break; |
| if (i == 0) |
| hookmask = (1 << hook) | (1 << NF_BR_NUMHOOKS); |
| else |
| hookmask = cl_s[i - 1].hookmask; |
| } |
| i = 0; |
| ret = EBT_MATCH_ITERATE(e, ebt_check_match, e, name, hookmask, &i); |
| if (ret != 0) |
| goto cleanup_matches; |
| j = 0; |
| ret = EBT_WATCHER_ITERATE(e, ebt_check_watcher, e, name, hookmask, &j); |
| if (ret != 0) |
| goto cleanup_watchers; |
| t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| target = find_target_lock(t->u.name, &ret, &ebt_mutex); |
| if (!target) |
| goto cleanup_watchers; |
| if (!try_module_get(target->me)) { |
| up(&ebt_mutex); |
| ret = -ENOENT; |
| goto cleanup_watchers; |
| } |
| up(&ebt_mutex); |
| |
| t->u.target = target; |
| if (t->u.target == &ebt_standard_target) { |
| if (e->target_offset + sizeof(struct ebt_standard_target) > |
| e->next_offset) { |
| BUGPRINT("Standard target size too big\n"); |
| ret = -EFAULT; |
| goto cleanup_watchers; |
| } |
| if (((struct ebt_standard_target *)t)->verdict < |
| -NUM_STANDARD_TARGETS) { |
| BUGPRINT("Invalid standard target\n"); |
| ret = -EFAULT; |
| goto cleanup_watchers; |
| } |
| } else if ((e->target_offset + t->target_size + |
| sizeof(struct ebt_entry_target) > e->next_offset) || |
| (t->u.target->check && |
| t->u.target->check(name, hookmask, e, t->data, t->target_size) != 0)){ |
| module_put(t->u.target->me); |
| ret = -EFAULT; |
| goto cleanup_watchers; |
| } |
| (*cnt)++; |
| return 0; |
| cleanup_watchers: |
| EBT_WATCHER_ITERATE(e, ebt_cleanup_watcher, &j); |
| cleanup_matches: |
| EBT_MATCH_ITERATE(e, ebt_cleanup_match, &i); |
| return ret; |
| } |
| |
| /* |
| * checks for loops and sets the hook mask for udc |
| * the hook mask for udc tells us from which base chains the udc can be |
| * accessed. This mask is a parameter to the check() functions of the extensions |
| */ |
| static int check_chainloops(struct ebt_entries *chain, struct ebt_cl_stack *cl_s, |
| unsigned int udc_cnt, unsigned int hooknr, char *base) |
| { |
| int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict; |
| struct ebt_entry *e = (struct ebt_entry *)chain->data; |
| struct ebt_entry_target *t; |
| |
| while (pos < nentries || chain_nr != -1) { |
| /* end of udc, go back one 'recursion' step */ |
| if (pos == nentries) { |
| /* put back values of the time when this chain was called */ |
| e = cl_s[chain_nr].cs.e; |
| if (cl_s[chain_nr].from != -1) |
| nentries = |
| cl_s[cl_s[chain_nr].from].cs.chaininfo->nentries; |
| else |
| nentries = chain->nentries; |
| pos = cl_s[chain_nr].cs.n; |
| /* make sure we won't see a loop that isn't one */ |
| cl_s[chain_nr].cs.n = 0; |
| chain_nr = cl_s[chain_nr].from; |
| if (pos == nentries) |
| continue; |
| } |
| t = (struct ebt_entry_target *) |
| (((char *)e) + e->target_offset); |
| if (strcmp(t->u.name, EBT_STANDARD_TARGET)) |
| goto letscontinue; |
| if (e->target_offset + sizeof(struct ebt_standard_target) > |
| e->next_offset) { |
| BUGPRINT("Standard target size too big\n"); |
| return -1; |
| } |
| verdict = ((struct ebt_standard_target *)t)->verdict; |
| if (verdict >= 0) { /* jump to another chain */ |
| struct ebt_entries *hlp2 = |
| (struct ebt_entries *)(base + verdict); |
| for (i = 0; i < udc_cnt; i++) |
| if (hlp2 == cl_s[i].cs.chaininfo) |
| break; |
| /* bad destination or loop */ |
| if (i == udc_cnt) { |
| BUGPRINT("bad destination\n"); |
| return -1; |
| } |
| if (cl_s[i].cs.n) { |
| BUGPRINT("loop\n"); |
| return -1; |
| } |
| /* this can't be 0, so the above test is correct */ |
| cl_s[i].cs.n = pos + 1; |
| pos = 0; |
| cl_s[i].cs.e = ((void *)e + e->next_offset); |
| e = (struct ebt_entry *)(hlp2->data); |
| nentries = hlp2->nentries; |
| cl_s[i].from = chain_nr; |
| chain_nr = i; |
| /* this udc is accessible from the base chain for hooknr */ |
| cl_s[i].hookmask |= (1 << hooknr); |
| continue; |
| } |
| letscontinue: |
| e = (void *)e + e->next_offset; |
| pos++; |
| } |
| return 0; |
| } |
| |
| /* do the parsing of the table/chains/entries/matches/watchers/targets, heh */ |
| static int translate_table(struct ebt_replace *repl, |
| struct ebt_table_info *newinfo) |
| { |
| unsigned int i, j, k, udc_cnt; |
| int ret; |
| struct ebt_cl_stack *cl_s = NULL; /* used in the checking for chain loops */ |
| |
| i = 0; |
| while (i < NF_BR_NUMHOOKS && !(repl->valid_hooks & (1 << i))) |
| i++; |
| if (i == NF_BR_NUMHOOKS) { |
| BUGPRINT("No valid hooks specified\n"); |
| return -EINVAL; |
| } |
| if (repl->hook_entry[i] != (struct ebt_entries *)repl->entries) { |
| BUGPRINT("Chains don't start at beginning\n"); |
| return -EINVAL; |
| } |
| /* make sure chains are ordered after each other in same order |
| as their corresponding hooks */ |
| for (j = i + 1; j < NF_BR_NUMHOOKS; j++) { |
| if (!(repl->valid_hooks & (1 << j))) |
| continue; |
| if ( repl->hook_entry[j] <= repl->hook_entry[i] ) { |
| BUGPRINT("Hook order must be followed\n"); |
| return -EINVAL; |
| } |
| i = j; |
| } |
| |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) |
| newinfo->hook_entry[i] = NULL; |
| |
| newinfo->entries_size = repl->entries_size; |
| newinfo->nentries = repl->nentries; |
| |
| /* do some early checkings and initialize some things */ |
| i = 0; /* holds the expected nr. of entries for the chain */ |
| j = 0; /* holds the up to now counted entries for the chain */ |
| k = 0; /* holds the total nr. of entries, should equal |
| newinfo->nentries afterwards */ |
| udc_cnt = 0; /* will hold the nr. of user defined chains (udc) */ |
| ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| ebt_check_entry_size_and_hooks, newinfo, repl->entries, |
| repl->entries + repl->entries_size, repl->hook_entry, &i, &j, &k, |
| &udc_cnt, repl->valid_hooks); |
| |
| if (ret != 0) |
| return ret; |
| |
| if (i != j) { |
| BUGPRINT("nentries does not equal the nr of entries in the " |
| "(last) chain\n"); |
| return -EINVAL; |
| } |
| if (k != newinfo->nentries) { |
| BUGPRINT("Total nentries is wrong\n"); |
| return -EINVAL; |
| } |
| |
| /* check if all valid hooks have a chain */ |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) { |
| if (newinfo->hook_entry[i] == NULL && |
| (repl->valid_hooks & (1 << i))) { |
| BUGPRINT("Valid hook without chain\n"); |
| return -EINVAL; |
| } |
| } |
| |
| /* get the location of the udc, put them in an array |
| while we're at it, allocate the chainstack */ |
| if (udc_cnt) { |
| /* this will get free'd in do_replace()/ebt_register_table() |
| if an error occurs */ |
| newinfo->chainstack = (struct ebt_chainstack **) |
| vmalloc((highest_possible_processor_id()+1) |
| * sizeof(struct ebt_chainstack)); |
| if (!newinfo->chainstack) |
| return -ENOMEM; |
| for_each_cpu(i) { |
| newinfo->chainstack[i] = |
| vmalloc(udc_cnt * sizeof(struct ebt_chainstack)); |
| if (!newinfo->chainstack[i]) { |
| while (i) |
| vfree(newinfo->chainstack[--i]); |
| vfree(newinfo->chainstack); |
| newinfo->chainstack = NULL; |
| return -ENOMEM; |
| } |
| } |
| |
| cl_s = (struct ebt_cl_stack *) |
| vmalloc(udc_cnt * sizeof(struct ebt_cl_stack)); |
| if (!cl_s) |
| return -ENOMEM; |
| i = 0; /* the i'th udc */ |
| EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| ebt_get_udc_positions, newinfo, repl->hook_entry, &i, |
| repl->valid_hooks, cl_s); |
| /* sanity check */ |
| if (i != udc_cnt) { |
| BUGPRINT("i != udc_cnt\n"); |
| vfree(cl_s); |
| return -EFAULT; |
| } |
| } |
| |
| /* Check for loops */ |
| for (i = 0; i < NF_BR_NUMHOOKS; i++) |
| if (repl->valid_hooks & (1 << i)) |
| if (check_chainloops(newinfo->hook_entry[i], |
| cl_s, udc_cnt, i, newinfo->entries)) { |
| vfree(cl_s); |
| return -EINVAL; |
| } |
| |
| /* we now know the following (along with E=mc²): |
| - the nr of entries in each chain is right |
| - the size of the allocated space is right |
| - all valid hooks have a corresponding chain |
| - there are no loops |
| - wrong data can still be on the level of a single entry |
| - could be there are jumps to places that are not the |
| beginning of a chain. This can only occur in chains that |
| are not accessible from any base chains, so we don't care. */ |
| |
| /* used to know what we need to clean up if something goes wrong */ |
| i = 0; |
| ret = EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| ebt_check_entry, newinfo, repl->name, &i, repl->valid_hooks, |
| cl_s, udc_cnt); |
| if (ret != 0) { |
| EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| ebt_cleanup_entry, &i); |
| } |
| vfree(cl_s); |
| return ret; |
| } |
| |
| /* called under write_lock */ |
| static void get_counters(struct ebt_counter *oldcounters, |
| struct ebt_counter *counters, unsigned int nentries) |
| { |
| int i, cpu; |
| struct ebt_counter *counter_base; |
| |
| /* counters of cpu 0 */ |
| memcpy(counters, oldcounters, |
| sizeof(struct ebt_counter) * nentries); |
| |
| /* add other counters to those of cpu 0 */ |
| for_each_cpu(cpu) { |
| if (cpu == 0) |
| continue; |
| counter_base = COUNTER_BASE(oldcounters, nentries, cpu); |
| for (i = 0; i < nentries; i++) { |
| counters[i].pcnt += counter_base[i].pcnt; |
| counters[i].bcnt += counter_base[i].bcnt; |
| } |
| } |
| } |
| |
| /* replace the table */ |
| static int do_replace(void __user *user, unsigned int len) |
| { |
| int ret, i, countersize; |
| struct ebt_table_info *newinfo; |
| struct ebt_replace tmp; |
| struct ebt_table *t; |
| struct ebt_counter *counterstmp = NULL; |
| /* used to be able to unlock earlier */ |
| struct ebt_table_info *table; |
| |
| if (copy_from_user(&tmp, user, sizeof(tmp)) != 0) |
| return -EFAULT; |
| |
| if (len != sizeof(tmp) + tmp.entries_size) { |
| BUGPRINT("Wrong len argument\n"); |
| return -EINVAL; |
| } |
| |
| if (tmp.entries_size == 0) { |
| BUGPRINT("Entries_size never zero\n"); |
| return -EINVAL; |
| } |
| countersize = COUNTER_OFFSET(tmp.nentries) * |
| (highest_possible_processor_id()+1); |
| newinfo = (struct ebt_table_info *) |
| vmalloc(sizeof(struct ebt_table_info) + countersize); |
| if (!newinfo) |
| return -ENOMEM; |
| |
| if (countersize) |
| memset(newinfo->counters, 0, countersize); |
| |
| newinfo->entries = (char *)vmalloc(tmp.entries_size); |
| if (!newinfo->entries) { |
| ret = -ENOMEM; |
| goto free_newinfo; |
| } |
| if (copy_from_user( |
| newinfo->entries, tmp.entries, tmp.entries_size) != 0) { |
| BUGPRINT("Couldn't copy entries from userspace\n"); |
| ret = -EFAULT; |
| goto free_entries; |
| } |
| |
| /* the user wants counters back |
| the check on the size is done later, when we have the lock */ |
| if (tmp.num_counters) { |
| counterstmp = (struct ebt_counter *) |
| vmalloc(tmp.num_counters * sizeof(struct ebt_counter)); |
| if (!counterstmp) { |
| ret = -ENOMEM; |
| goto free_entries; |
| } |
| } |
| else |
| counterstmp = NULL; |
| |
| /* this can get initialized by translate_table() */ |
| newinfo->chainstack = NULL; |
| ret = translate_table(&tmp, newinfo); |
| |
| if (ret != 0) |
| goto free_counterstmp; |
| |
| t = find_table_lock(tmp.name, &ret, &ebt_mutex); |
| if (!t) { |
| ret = -ENOENT; |
| goto free_iterate; |
| } |
| |
| /* the table doesn't like it */ |
| if (t->check && (ret = t->check(newinfo, tmp.valid_hooks))) |
| goto free_unlock; |
| |
| if (tmp.num_counters && tmp.num_counters != t->private->nentries) { |
| BUGPRINT("Wrong nr. of counters requested\n"); |
| ret = -EINVAL; |
| goto free_unlock; |
| } |
| |
| /* we have the mutex lock, so no danger in reading this pointer */ |
| table = t->private; |
| /* make sure the table can only be rmmod'ed if it contains no rules */ |
| if (!table->nentries && newinfo->nentries && !try_module_get(t->me)) { |
| ret = -ENOENT; |
| goto free_unlock; |
| } else if (table->nentries && !newinfo->nentries) |
| module_put(t->me); |
| /* we need an atomic snapshot of the counters */ |
| write_lock_bh(&t->lock); |
| if (tmp.num_counters) |
| get_counters(t->private->counters, counterstmp, |
| t->private->nentries); |
| |
| t->private = newinfo; |
| write_unlock_bh(&t->lock); |
| up(&ebt_mutex); |
| /* so, a user can change the chains while having messed up her counter |
| allocation. Only reason why this is done is because this way the lock |
| is held only once, while this doesn't bring the kernel into a |
| dangerous state. */ |
| if (tmp.num_counters && |
| copy_to_user(tmp.counters, counterstmp, |
| tmp.num_counters * sizeof(struct ebt_counter))) { |
| BUGPRINT("Couldn't copy counters to userspace\n"); |
| ret = -EFAULT; |
| } |
| else |
| ret = 0; |
| |
| /* decrease module count and free resources */ |
| EBT_ENTRY_ITERATE(table->entries, table->entries_size, |
| ebt_cleanup_entry, NULL); |
| |
| vfree(table->entries); |
| if (table->chainstack) { |
| for_each_cpu(i) |
| vfree(table->chainstack[i]); |
| vfree(table->chainstack); |
| } |
| vfree(table); |
| |
| vfree(counterstmp); |
| return ret; |
| |
| free_unlock: |
| up(&ebt_mutex); |
| free_iterate: |
| EBT_ENTRY_ITERATE(newinfo->entries, newinfo->entries_size, |
| ebt_cleanup_entry, NULL); |
| free_counterstmp: |
| vfree(counterstmp); |
| /* can be initialized in translate_table() */ |
| if (newinfo->chainstack) { |
| for_each_cpu(i) |
| vfree(newinfo->chainstack[i]); |
| vfree(newinfo->chainstack); |
| } |
| free_entries: |
| vfree(newinfo->entries); |
| free_newinfo: |
| vfree(newinfo); |
| return ret; |
| } |
| |
| int ebt_register_target(struct ebt_target *target) |
| { |
| int ret; |
| |
| ret = down_interruptible(&ebt_mutex); |
| if (ret != 0) |
| return ret; |
| if (!list_named_insert(&ebt_targets, target)) { |
| up(&ebt_mutex); |
| return -EEXIST; |
| } |
| up(&ebt_mutex); |
| |
| return 0; |
| } |
| |
| void ebt_unregister_target(struct ebt_target *target) |
| { |
| down(&ebt_mutex); |
| LIST_DELETE(&ebt_targets, target); |
| up(&ebt_mutex); |
| } |
| |
| int ebt_register_match(struct ebt_match *match) |
| { |
| int ret; |
| |
| ret = down_interruptible(&ebt_mutex); |
| if (ret != 0) |
| return ret; |
| if (!list_named_insert(&ebt_matches, match)) { |
| up(&ebt_mutex); |
| return -EEXIST; |
| } |
| up(&ebt_mutex); |
| |
| return 0; |
| } |
| |
| void ebt_unregister_match(struct ebt_match *match) |
| { |
| down(&ebt_mutex); |
| LIST_DELETE(&ebt_matches, match); |
| up(&ebt_mutex); |
| } |
| |
| int ebt_register_watcher(struct ebt_watcher *watcher) |
| { |
| int ret; |
| |
| ret = down_interruptible(&ebt_mutex); |
| if (ret != 0) |
| return ret; |
| if (!list_named_insert(&ebt_watchers, watcher)) { |
| up(&ebt_mutex); |
| return -EEXIST; |
| } |
| up(&ebt_mutex); |
| |
| return 0; |
| } |
| |
| void ebt_unregister_watcher(struct ebt_watcher *watcher) |
| { |
| down(&ebt_mutex); |
| LIST_DELETE(&ebt_watchers, watcher); |
| up(&ebt_mutex); |
| } |
| |
| int ebt_register_table(struct ebt_table *table) |
| { |
| struct ebt_table_info *newinfo; |
| int ret, i, countersize; |
| |
| if (!table || !table->table ||!table->table->entries || |
| table->table->entries_size == 0 || |
| table->table->counters || table->private) { |
| BUGPRINT("Bad table data for ebt_register_table!!!\n"); |
| return -EINVAL; |
| } |
| |
| countersize = COUNTER_OFFSET(table->table->nentries) * |
| (highest_possible_processor_id()+1); |
| newinfo = (struct ebt_table_info *) |
| vmalloc(sizeof(struct ebt_table_info) + countersize); |
| ret = -ENOMEM; |
| if (!newinfo) |
| return -ENOMEM; |
| |
| newinfo->entries = (char *)vmalloc(table->table->entries_size); |
| if (!(newinfo->entries)) |
| goto free_newinfo; |
| |
| memcpy(newinfo->entries, table->table->entries, |
| table->table->entries_size); |
| |
| if (countersize) |
| memset(newinfo->counters, 0, countersize); |
| |
| /* fill in newinfo and parse the entries */ |
| newinfo->chainstack = NULL; |
| ret = translate_table(table->table, newinfo); |
| if (ret != 0) { |
| BUGPRINT("Translate_table failed\n"); |
| goto free_chainstack; |
| } |
| |
| if (table->check && table->check(newinfo, table->valid_hooks)) { |
| BUGPRINT("The table doesn't like its own initial data, lol\n"); |
| return -EINVAL; |
| } |
| |
| table->private = newinfo; |
| rwlock_init(&table->lock); |
| ret = down_interruptible(&ebt_mutex); |
| if (ret != 0) |
| goto free_chainstack; |
| |
| if (list_named_find(&ebt_tables, table->name)) { |
| ret = -EEXIST; |
| BUGPRINT("Table name already exists\n"); |
| goto free_unlock; |
| } |
| |
| /* Hold a reference count if the chains aren't empty */ |
| if (newinfo->nentries && !try_module_get(table->me)) { |
| ret = -ENOENT; |
| goto free_unlock; |
| } |
| list_prepend(&ebt_tables, table); |
| up(&ebt_mutex); |
| return 0; |
| free_unlock: |
| up(&ebt_mutex); |
| free_chainstack: |
| if (newinfo->chainstack) { |
| for_each_cpu(i) |
| vfree(newinfo->chainstack[i]); |
| vfree(newinfo->chainstack); |
| } |
| vfree(newinfo->entries); |
| free_newinfo: |
| vfree(newinfo); |
| return ret; |
| } |
| |
| void ebt_unregister_table(struct ebt_table *table) |
| { |
| int i; |
| |
| if (!table) { |
| BUGPRINT("Request to unregister NULL table!!!\n"); |
| return; |
| } |
| down(&ebt_mutex); |
| LIST_DELETE(&ebt_tables, table); |
| up(&ebt_mutex); |
| vfree(table->private->entries); |
| if (table->private->chainstack) { |
| for_each_cpu(i) |
| vfree(table->private->chainstack[i]); |
| vfree(table->private->chainstack); |
| } |
| vfree(table->private); |
| } |
| |
| /* userspace just supplied us with counters */ |
| static int update_counters(void __user *user, unsigned int len) |
| { |
| int i, ret; |
| struct ebt_counter *tmp; |
| struct ebt_replace hlp; |
| struct ebt_table *t; |
| |
| if (copy_from_user(&hlp, user, sizeof(hlp))) |
| return -EFAULT; |
| |
| if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) |
| return -EINVAL; |
| if (hlp.num_counters == 0) |
| return -EINVAL; |
| |
| if ( !(tmp = (struct ebt_counter *) |
| vmalloc(hlp.num_counters * sizeof(struct ebt_counter))) ){ |
| MEMPRINT("Update_counters && nomemory\n"); |
| return -ENOMEM; |
| } |
| |
| t = find_table_lock(hlp.name, &ret, &ebt_mutex); |
| if (!t) |
| goto free_tmp; |
| |
| if (hlp.num_counters != t->private->nentries) { |
| BUGPRINT("Wrong nr of counters\n"); |
| ret = -EINVAL; |
| goto unlock_mutex; |
| } |
| |
| if ( copy_from_user(tmp, hlp.counters, |
| hlp.num_counters * sizeof(struct ebt_counter)) ) { |
| BUGPRINT("Updata_counters && !cfu\n"); |
| ret = -EFAULT; |
| goto unlock_mutex; |
| } |
| |
| /* we want an atomic add of the counters */ |
| write_lock_bh(&t->lock); |
| |
| /* we add to the counters of the first cpu */ |
| for (i = 0; i < hlp.num_counters; i++) { |
| t->private->counters[i].pcnt += tmp[i].pcnt; |
| t->private->counters[i].bcnt += tmp[i].bcnt; |
| } |
| |
| write_unlock_bh(&t->lock); |
| ret = 0; |
| unlock_mutex: |
| up(&ebt_mutex); |
| free_tmp: |
| vfree(tmp); |
| return ret; |
| } |
| |
| static inline int ebt_make_matchname(struct ebt_entry_match *m, |
| char *base, char *ubase) |
| { |
| char *hlp = ubase - base + (char *)m; |
| if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| static inline int ebt_make_watchername(struct ebt_entry_watcher *w, |
| char *base, char *ubase) |
| { |
| char *hlp = ubase - base + (char *)w; |
| if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| static inline int ebt_make_names(struct ebt_entry *e, char *base, char *ubase) |
| { |
| int ret; |
| char *hlp; |
| struct ebt_entry_target *t; |
| |
| if ((e->bitmask & EBT_ENTRY_OR_ENTRIES) == 0) |
| return 0; |
| |
| hlp = ubase - base + (char *)e + e->target_offset; |
| t = (struct ebt_entry_target *)(((char *)e) + e->target_offset); |
| |
| ret = EBT_MATCH_ITERATE(e, ebt_make_matchname, base, ubase); |
| if (ret != 0) |
| return ret; |
| ret = EBT_WATCHER_ITERATE(e, ebt_make_watchername, base, ubase); |
| if (ret != 0) |
| return ret; |
| if (copy_to_user(hlp, t->u.target->name, EBT_FUNCTION_MAXNAMELEN)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| /* called with ebt_mutex down */ |
| static int copy_everything_to_user(struct ebt_table *t, void __user *user, |
| int *len, int cmd) |
| { |
| struct ebt_replace tmp; |
| struct ebt_counter *counterstmp, *oldcounters; |
| unsigned int entries_size, nentries; |
| char *entries; |
| |
| if (cmd == EBT_SO_GET_ENTRIES) { |
| entries_size = t->private->entries_size; |
| nentries = t->private->nentries; |
| entries = t->private->entries; |
| oldcounters = t->private->counters; |
| } else { |
| entries_size = t->table->entries_size; |
| nentries = t->table->nentries; |
| entries = t->table->entries; |
| oldcounters = t->table->counters; |
| } |
| |
| if (copy_from_user(&tmp, user, sizeof(tmp))) { |
| BUGPRINT("Cfu didn't work\n"); |
| return -EFAULT; |
| } |
| |
| if (*len != sizeof(struct ebt_replace) + entries_size + |
| (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) { |
| BUGPRINT("Wrong size\n"); |
| return -EINVAL; |
| } |
| |
| if (tmp.nentries != nentries) { |
| BUGPRINT("Nentries wrong\n"); |
| return -EINVAL; |
| } |
| |
| if (tmp.entries_size != entries_size) { |
| BUGPRINT("Wrong size\n"); |
| return -EINVAL; |
| } |
| |
| /* userspace might not need the counters */ |
| if (tmp.num_counters) { |
| if (tmp.num_counters != nentries) { |
| BUGPRINT("Num_counters wrong\n"); |
| return -EINVAL; |
| } |
| counterstmp = (struct ebt_counter *) |
| vmalloc(nentries * sizeof(struct ebt_counter)); |
| if (!counterstmp) { |
| MEMPRINT("Couldn't copy counters, out of memory\n"); |
| return -ENOMEM; |
| } |
| write_lock_bh(&t->lock); |
| get_counters(oldcounters, counterstmp, nentries); |
| write_unlock_bh(&t->lock); |
| |
| if (copy_to_user(tmp.counters, counterstmp, |
| nentries * sizeof(struct ebt_counter))) { |
| BUGPRINT("Couldn't copy counters to userspace\n"); |
| vfree(counterstmp); |
| return -EFAULT; |
| } |
| vfree(counterstmp); |
| } |
| |
| if (copy_to_user(tmp.entries, entries, entries_size)) { |
| BUGPRINT("Couldn't copy entries to userspace\n"); |
| return -EFAULT; |
| } |
| /* set the match/watcher/target names right */ |
| return EBT_ENTRY_ITERATE(entries, entries_size, |
| ebt_make_names, entries, tmp.entries); |
| } |
| |
| static int do_ebt_set_ctl(struct sock *sk, |
| int cmd, void __user *user, unsigned int len) |
| { |
| int ret; |
| |
| switch(cmd) { |
| case EBT_SO_SET_ENTRIES: |
| ret = do_replace(user, len); |
| break; |
| case EBT_SO_SET_COUNTERS: |
| ret = update_counters(user, len); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| return ret; |
| } |
| |
| static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) |
| { |
| int ret; |
| struct ebt_replace tmp; |
| struct ebt_table *t; |
| |
| if (copy_from_user(&tmp, user, sizeof(tmp))) |
| return -EFAULT; |
| |
| t = find_table_lock(tmp.name, &ret, &ebt_mutex); |
| if (!t) |
| return ret; |
| |
| switch(cmd) { |
| case EBT_SO_GET_INFO: |
| case EBT_SO_GET_INIT_INFO: |
| if (*len != sizeof(struct ebt_replace)){ |
| ret = -EINVAL; |
| up(&ebt_mutex); |
| break; |
| } |
| if (cmd == EBT_SO_GET_INFO) { |
| tmp.nentries = t->private->nentries; |
| tmp.entries_size = t->private->entries_size; |
| tmp.valid_hooks = t->valid_hooks; |
| } else { |
| tmp.nentries = t->table->nentries; |
| tmp.entries_size = t->table->entries_size; |
| tmp.valid_hooks = t->table->valid_hooks; |
| } |
| up(&ebt_mutex); |
| if (copy_to_user(user, &tmp, *len) != 0){ |
| BUGPRINT("c2u Didn't work\n"); |
| ret = -EFAULT; |
| break; |
| } |
| ret = 0; |
| break; |
| |
| case EBT_SO_GET_ENTRIES: |
| case EBT_SO_GET_INIT_ENTRIES: |
| ret = copy_everything_to_user(t, user, len, cmd); |
| up(&ebt_mutex); |
| break; |
| |
| default: |
| up(&ebt_mutex); |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| static struct nf_sockopt_ops ebt_sockopts = |
| { { NULL, NULL }, PF_INET, EBT_BASE_CTL, EBT_SO_SET_MAX + 1, do_ebt_set_ctl, |
| EBT_BASE_CTL, EBT_SO_GET_MAX + 1, do_ebt_get_ctl, 0, NULL |
| }; |
| |
| static int __init init(void) |
| { |
| int ret; |
| |
| down(&ebt_mutex); |
| list_named_insert(&ebt_targets, &ebt_standard_target); |
| up(&ebt_mutex); |
| if ((ret = nf_register_sockopt(&ebt_sockopts)) < 0) |
| return ret; |
| |
| printk(KERN_NOTICE "Ebtables v2.0 registered\n"); |
| return 0; |
| } |
| |
| static void __exit fini(void) |
| { |
| nf_unregister_sockopt(&ebt_sockopts); |
| printk(KERN_NOTICE "Ebtables v2.0 unregistered\n"); |
| } |
| |
| EXPORT_SYMBOL(ebt_register_table); |
| EXPORT_SYMBOL(ebt_unregister_table); |
| EXPORT_SYMBOL(ebt_register_match); |
| EXPORT_SYMBOL(ebt_unregister_match); |
| EXPORT_SYMBOL(ebt_register_watcher); |
| EXPORT_SYMBOL(ebt_unregister_watcher); |
| EXPORT_SYMBOL(ebt_register_target); |
| EXPORT_SYMBOL(ebt_unregister_target); |
| EXPORT_SYMBOL(ebt_do_table); |
| module_init(init); |
| module_exit(fini); |
| MODULE_LICENSE("GPL"); |