diff options
Diffstat (limited to 'net/ipv4/netfilter/ip_tables.c')
-rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 259 |
1 files changed, 44 insertions, 215 deletions
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 0984ea3fc..54906e0e8 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -35,34 +35,12 @@ 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...) pr_info(format , ## args) -#else -#define dprintf(format, args...) -#endif - -#ifdef DEBUG_IP_FIREWALL_USER -#define duprintf(format, args...) pr_info(format , ## args) -#else -#define duprintf(format, args...) -#endif - #ifdef CONFIG_NETFILTER_DEBUG #define IP_NF_ASSERT(x) WARN_ON(!(x)) #else #define IP_NF_ASSERT(x) #endif -#if 0 -/* All the better to debug you with... */ -#define static -#define inline -#endif - void *ipt_alloc_initial_table(const struct xt_table *info) { return xt_alloc_initial_table(ipt, IPT); @@ -85,52 +63,28 @@ ip_packet_match(const struct iphdr *ip, 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: %pI4. Mask: %pI4. Target: %pI4.%s\n", - &ip->saddr, &ipinfo->smsk.s_addr, &ipinfo->src.s_addr, - ipinfo->invflags & IPT_INV_SRCIP ? " (INV)" : ""); - dprintf("DST: %pI4 Mask: %pI4 Target: %pI4.%s\n", - &ip->daddr, &ipinfo->dmsk.s_addr, &ipinfo->dst.s_addr, - ipinfo->invflags & IPT_INV_DSTIP ? " (INV)" : ""); + IPT_INV_DSTIP)) return false; - } ret = ifname_compare_aligned(indev, ipinfo->iniface, ipinfo->iniface_mask); - 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)" : ""); + if (FWINV(ret != 0, IPT_INV_VIA_IN)) return false; - } ret = ifname_compare_aligned(outdev, ipinfo->outiface, ipinfo->outiface_mask); - 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)" : ""); + if (FWINV(ret != 0, IPT_INV_VIA_OUT)) return false; - } /* 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)" : ""); + FWINV(ip->protocol != ipinfo->proto, IPT_INV_PROTO)) return false; - } /* 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)" : ""); + if (FWINV((ipinfo->flags&IPT_F_FRAG) && !isfrag, IPT_INV_FRAG)) return false; - } return true; } @@ -138,16 +92,10 @@ ip_packet_match(const struct iphdr *ip, static bool 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); + if (ip->flags & ~IPT_F_MASK) return false; - } - if (ip->invflags & ~IPT_INV_MASK) { - duprintf("Unknown invflag bits set: %08X\n", - ip->invflags & ~IPT_INV_MASK); + if (ip->invflags & ~IPT_INV_MASK) return false; - } return true; } @@ -346,10 +294,6 @@ ipt_do_table(struct sk_buff *skb, e = get_entry(table_base, private->hook_entry[hook]); - pr_debug("Entering %s(hook %u), UF %p\n", - table->name, hook, - get_entry(table_base, private->underflow[hook])); - do { const struct xt_entry_target *t; const struct xt_entry_match *ematch; @@ -396,22 +340,15 @@ ipt_do_table(struct sk_buff *skb, if (stackidx == 0) { e = get_entry(table_base, private->underflow[hook]); - pr_debug("Underflow (this is normal) " - "to %p\n", e); } else { e = jumpstack[--stackidx]; - pr_debug("Pulled %p out from pos %u\n", - e, stackidx); e = ipt_next_entry(e); } continue; } if (table_base + v != ipt_next_entry(e) && - !(e->ip.flags & IPT_F_GOTO)) { + !(e->ip.flags & IPT_F_GOTO)) jumpstack[stackidx++] = e; - pr_debug("Pushed %p into pos %u\n", - e, stackidx - 1); - } e = get_entry(table_base, v); continue; @@ -429,18 +366,13 @@ ipt_do_table(struct sk_buff *skb, /* Verdict */ break; } while (!acpar.hotdrop); - pr_debug("Exiting %s; sp at %u\n", __func__, stackidx); xt_write_recseq_end(addend); local_bh_enable(); -#ifdef DEBUG_ALLOW_ALL - return NF_ACCEPT; -#else if (acpar.hotdrop) return NF_DROP; else return verdict; -#endif } static bool find_jump_target(const struct xt_table_info *t, @@ -480,11 +412,9 @@ mark_source_chains(const struct xt_table_info *newinfo, = (void *)ipt_get_target_c(e); int visited = e->comefrom & (1 << hook); - if (e->comefrom & (1 << NF_INET_NUMHOOKS)) { - pr_err("iptables: loop hook %u pos %u %08X.\n", - hook, pos, e->comefrom); + if (e->comefrom & (1 << NF_INET_NUMHOOKS)) return 0; - } + e->comefrom |= ((1 << hook) | (1 << NF_INET_NUMHOOKS)); /* Unconditional return/END. */ @@ -496,26 +426,13 @@ mark_source_chains(const struct xt_table_info *newinfo, if ((strcmp(t->target.u.user.name, XT_STANDARD_TARGET) == 0) && - t->verdict < -NF_MAX_VERDICT - 1) { - duprintf("mark_source_chains: bad " - "negative verdict (%i)\n", - t->verdict); + t->verdict < -NF_MAX_VERDICT - 1) return 0; - } /* Return: backtrack through the last big jump. */ do { e->comefrom ^= (1<<NF_INET_NUMHOOKS); -#ifdef DEBUG_IP_FIREWALL_USER - if (e->comefrom - & (1 << NF_INET_NUMHOOKS)) { - duprintf("Back unset " - "on hook %u " - "rule %u\n", - hook, pos); - } -#endif oldpos = pos; pos = e->counters.pcnt; e->counters.pcnt = 0; @@ -542,16 +459,7 @@ mark_source_chains(const struct xt_table_info *newinfo, if (strcmp(t->target.u.user.name, XT_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); e = (struct ipt_entry *) (entry0 + newpos); if (!find_jump_target(newinfo, e)) @@ -568,8 +476,7 @@ mark_source_chains(const struct xt_table_info *newinfo, pos = newpos; } } -next: - duprintf("Finished chain %u\n", hook); +next: ; } return 1; } @@ -591,18 +498,12 @@ static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par) { const struct ipt_ip *ip = par->entryinfo; - int ret; par->match = m->u.kernel.match; par->matchinfo = m->data; - ret = xt_check_match(par, m->u.match_size - sizeof(*m), - ip->proto, ip->invflags & IPT_INV_PROTO); - if (ret < 0) { - duprintf("check failed for `%s'.\n", par->match->name); - return ret; - } - return 0; + return xt_check_match(par, m->u.match_size - sizeof(*m), + ip->proto, ip->invflags & IPT_INV_PROTO); } static int @@ -613,10 +514,8 @@ find_check_match(struct xt_entry_match *m, struct xt_mtchk_param *par) match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name, m->u.user.revision); - if (IS_ERR(match)) { - duprintf("find_check_match: `%s' not found\n", m->u.user.name); + if (IS_ERR(match)) return PTR_ERR(match); - } m->u.kernel.match = match; ret = check_match(m, par); @@ -641,16 +540,9 @@ static int check_target(struct ipt_entry *e, struct net *net, const char *name) .hook_mask = e->comefrom, .family = NFPROTO_IPV4, }; - int ret; - ret = xt_check_target(&par, t->u.target_size - sizeof(*t), - e->ip.proto, e->ip.invflags & IPT_INV_PROTO); - if (ret < 0) { - duprintf("check failed for `%s'.\n", - t->u.kernel.target->name); - return ret; - } - return 0; + return xt_check_target(&par, t->u.target_size - sizeof(*t), + e->ip.proto, e->ip.invflags & IPT_INV_PROTO); } static int @@ -663,10 +555,12 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name, unsigned int j; struct xt_mtchk_param mtpar; struct xt_entry_match *ematch; + unsigned long pcnt; - e->counters.pcnt = xt_percpu_counter_alloc(); - if (IS_ERR_VALUE(e->counters.pcnt)) + pcnt = xt_percpu_counter_alloc(); + if (IS_ERR_VALUE(pcnt)) return -ENOMEM; + e->counters.pcnt = pcnt; j = 0; mtpar.net = net; @@ -685,7 +579,6 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name, target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name, t->u.user.revision); if (IS_ERR(target)) { - duprintf("find_check_entry: `%s' not found\n", t->u.user.name); ret = PTR_ERR(target); goto cleanup_matches; } @@ -739,17 +632,12 @@ check_entry_size_and_hooks(struct ipt_entry *e, if ((unsigned long)e % __alignof__(struct ipt_entry) != 0 || (unsigned char *)e + sizeof(struct ipt_entry) >= limit || - (unsigned char *)e + e->next_offset > limit) { - duprintf("Bad offset %p\n", e); + (unsigned char *)e + e->next_offset > limit) return -EINVAL; - } if (e->next_offset - < sizeof(struct ipt_entry) + sizeof(struct xt_entry_target)) { - duprintf("checking: element %p size %u\n", - e, e->next_offset); + < sizeof(struct ipt_entry) + sizeof(struct xt_entry_target)) return -EINVAL; - } if (!ip_checkentry(&e->ip)) return -EINVAL; @@ -766,12 +654,9 @@ check_entry_size_and_hooks(struct ipt_entry *e, if ((unsigned char *)e - base == hook_entries[h]) newinfo->hook_entry[h] = hook_entries[h]; if ((unsigned char *)e - base == underflows[h]) { - if (!check_underflow(e)) { - pr_debug("Underflows must be unconditional and " - "use the STANDARD target with " - "ACCEPT/DROP\n"); + if (!check_underflow(e)) return -EINVAL; - } + newinfo->underflow[h] = underflows[h]; } } @@ -823,7 +708,6 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, newinfo->underflow[i] = 0xFFFFFFFF; } - duprintf("translate_table: size %u\n", newinfo->size); i = 0; /* Walk through entries, checking offsets. */ xt_entry_foreach(iter, entry0, newinfo->size) { @@ -840,27 +724,18 @@ translate_table(struct net *net, struct xt_table_info *newinfo, void *entry0, ++newinfo->stacksize; } - if (i != repl->num_entries) { - duprintf("translate_table: %u not %u entries\n", - i, repl->num_entries); + if (i != repl->num_entries) return -EINVAL; - } /* Check hooks all assigned */ for (i = 0; i < NF_INET_NUMHOOKS; i++) { /* Only hooks which are valid */ if (!(repl->valid_hooks & (1 << i))) continue; - if (newinfo->hook_entry[i] == 0xFFFFFFFF) { - duprintf("Invalid hook entry %u %u\n", - i, repl->hook_entry[i]); + if (newinfo->hook_entry[i] == 0xFFFFFFFF) return -EINVAL; - } - if (newinfo->underflow[i] == 0xFFFFFFFF) { - duprintf("Invalid underflow %u %u\n", - i, repl->underflow[i]); + if (newinfo->underflow[i] == 0xFFFFFFFF) return -EINVAL; - } } if (!mark_source_chains(newinfo, repl->valid_hooks, entry0)) @@ -1088,11 +963,8 @@ static int get_info(struct net *net, void __user *user, struct xt_table *t; int ret; - if (*len != sizeof(struct ipt_getinfo)) { - duprintf("length %u != %zu\n", *len, - sizeof(struct ipt_getinfo)); + if (*len != sizeof(struct ipt_getinfo)) return -EINVAL; - } if (copy_from_user(name, user, sizeof(name)) != 0) return -EFAULT; @@ -1150,31 +1022,23 @@ get_entries(struct net *net, struct ipt_get_entries __user *uptr, struct ipt_get_entries get; struct xt_table *t; - if (*len < sizeof(get)) { - duprintf("get_entries: %u < %zu\n", *len, sizeof(get)); + if (*len < 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 != %zu\n", - *len, sizeof(get) + get.size); + if (*len != sizeof(struct ipt_get_entries) + get.size) return -EINVAL; - } get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, AF_INET, get.name); if (!IS_ERR_OR_NULL(t)) { const 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); + else ret = -EAGAIN; - } + module_put(t->me); xt_table_unlock(t); } else @@ -1210,8 +1074,6 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, /* 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; } @@ -1221,8 +1083,6 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks, 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); @@ -1291,8 +1151,6 @@ do_replace(struct net *net, const void __user *user, unsigned int len) if (ret != 0) goto free_newinfo; - duprintf("Translated table\n"); - ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, tmp.num_counters, tmp.counters); if (ret) @@ -1418,11 +1276,9 @@ compat_find_calc_match(struct xt_entry_match *m, match = xt_request_find_match(NFPROTO_IPV4, m->u.user.name, m->u.user.revision); - if (IS_ERR(match)) { - duprintf("compat_check_calc_match: `%s' not found\n", - m->u.user.name); + if (IS_ERR(match)) return PTR_ERR(match); - } + m->u.kernel.match = match; *size += xt_compat_match_offset(match); return 0; @@ -1454,20 +1310,14 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, unsigned int j; int ret, off; - 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 || - (unsigned char *)e + e->next_offset > limit) { - duprintf("Bad offset %p, limit = %p\n", e, limit); + (unsigned char *)e + e->next_offset > 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); + sizeof(struct compat_xt_entry_target)) return -EINVAL; - } if (!ip_checkentry(&e->ip)) return -EINVAL; @@ -1491,8 +1341,6 @@ check_compat_entry_size_and_hooks(struct compat_ipt_entry *e, target = xt_request_find_target(NFPROTO_IPV4, t->u.user.name, t->u.user.revision); if (IS_ERR(target)) { - duprintf("check_compat_entry_size_and_hooks: `%s' not found\n", - t->u.user.name); ret = PTR_ERR(target); goto release_matches; } @@ -1574,7 +1422,6 @@ translate_compat_table(struct net *net, size = compatr->size; info->number = compatr->num_entries; - duprintf("translate_compat_table: size %u\n", info->size); j = 0; xt_compat_lock(AF_INET); xt_compat_init_offsets(AF_INET, compatr->num_entries); @@ -1589,11 +1436,8 @@ translate_compat_table(struct net *net, } ret = -EINVAL; - if (j != compatr->num_entries) { - duprintf("translate_compat_table: %u not %u entries\n", - j, compatr->num_entries); + if (j != compatr->num_entries) goto out_unlock; - } ret = -ENOMEM; newinfo = xt_alloc_table_info(size); @@ -1668,8 +1512,6 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) return -EFAULT; /* overflow check */ - if (tmp.size >= INT_MAX / num_possible_cpus()) - return -ENOMEM; if (tmp.num_counters >= INT_MAX / sizeof(struct xt_counters)) return -ENOMEM; if (tmp.num_counters == 0) @@ -1692,8 +1534,6 @@ compat_do_replace(struct net *net, void __user *user, unsigned int len) if (ret != 0) goto free_newinfo; - duprintf("compat_do_replace: Translated table\n"); - ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo, tmp.num_counters, compat_ptr(tmp.counters)); if (ret) @@ -1727,7 +1567,6 @@ compat_do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user, break; default: - duprintf("do_ipt_set_ctl: unknown request %i\n", cmd); ret = -EINVAL; } @@ -1777,19 +1616,15 @@ compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr, struct compat_ipt_get_entries get; struct xt_table *t; - if (*len < sizeof(get)) { - duprintf("compat_get_entries: %u < %zu\n", *len, sizeof(get)); + if (*len < 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 != %zu\n", - *len, sizeof(get) + get.size); + if (*len != sizeof(struct compat_ipt_get_entries) + get.size) return -EINVAL; - } + get.name[sizeof(get.name) - 1] = '\0'; xt_compat_lock(AF_INET); @@ -1797,16 +1632,13 @@ compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr, if (!IS_ERR_OR_NULL(t)) { const 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) { + 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); + else if (!ret) ret = -EAGAIN; - } + xt_compat_flush_offsets(AF_INET); module_put(t->me); xt_table_unlock(t); @@ -1859,7 +1691,6 @@ do_ipt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned int len) break; default: - duprintf("do_ipt_set_ctl: unknown request %i\n", cmd); ret = -EINVAL; } @@ -1911,7 +1742,6 @@ do_ipt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) } default: - duprintf("do_ipt_get_ctl: unknown request %i\n", cmd); ret = -EINVAL; } @@ -2013,7 +1843,6 @@ icmp_match(const struct sk_buff *skb, struct xt_action_param *par) /* We've been asked to examine this packet, and we * can't. Hence, no choice but to drop. */ - duprintf("Dropping evil ICMP tinygram.\n"); par->hotdrop = true; return false; } |