diff options
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/ip_fragment.c | 2 | ||||
-rw-r--r-- | net/ipv4/netfilter/Kconfig | 20 | ||||
-rw-r--r-- | net/ipv4/netfilter/Makefile | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_amanda.c | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_core.c | 38 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_ftp.c | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_irc.c | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_netbios_ns.c | 131 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_netlink.c | 13 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_proto_tcp.c | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_standalone.c | 2 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_conntrack_tftp.c | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_nat_rule.c | 21 | ||||
-rw-r--r-- | net/ipv4/netfilter/ip_nat_standalone.c | 8 |
14 files changed, 213 insertions, 28 deletions
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 9e6e683cc34..e7d26d9943c 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -457,7 +457,7 @@ static void ip_frag_queue(struct ipq *qp, struct sk_buff *skb) if (pskb_pull(skb, ihl) == NULL) goto err; - if (pskb_trim(skb, end-offset)) + if (pskb_trim_rcsum(skb, end-offset)) goto err; /* Find out which fragments are in front and at the back of us diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index e046f552181..30aa8e2ee21 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -34,6 +34,7 @@ config IP_NF_CT_ACCT config IP_NF_CONNTRACK_MARK bool 'Connection mark tracking support' + depends on IP_NF_CONNTRACK help This option enables support for connection marks, used by the `CONNMARK' target and `connmark' match. Similar to the mark value @@ -85,6 +86,25 @@ config IP_NF_IRC To compile it as a module, choose M here. If unsure, say Y. +config IP_NF_NETBIOS_NS + tristate "NetBIOS name service protocol support (EXPERIMENTAL)" + depends on IP_NF_CONNTRACK && EXPERIMENTAL + help + NetBIOS name service requests are sent as broadcast messages from an + unprivileged port and responded to with unicast messages to the + same port. This make them hard to firewall properly because connection + tracking doesn't deal with broadcasts. This helper tracks locally + originating NetBIOS name service requests and the corresponding + responses. It relies on correct IP address configuration, specifically + netmask and broadcast address. When properly configured, the output + of "ip address show" should look similar to this: + + $ ip -4 address show eth0 + 4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000 + inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0 + + To compile it as a module, choose M here. If unsure, say N. + config IP_NF_TFTP tristate "TFTP protocol support" depends on IP_NF_CONNTRACK diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index a7bd38f5052..1ba0db74681 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_IP_NF_AMANDA) += ip_conntrack_amanda.o obj-$(CONFIG_IP_NF_TFTP) += ip_conntrack_tftp.o obj-$(CONFIG_IP_NF_FTP) += ip_conntrack_ftp.o obj-$(CONFIG_IP_NF_IRC) += ip_conntrack_irc.o +obj-$(CONFIG_IP_NF_NETBIOS_NS) += ip_conntrack_netbios_ns.o # NAT helpers obj-$(CONFIG_IP_NF_NAT_AMANDA) += ip_nat_amanda.o diff --git a/net/ipv4/netfilter/ip_conntrack_amanda.c b/net/ipv4/netfilter/ip_conntrack_amanda.c index be4c9eb3243..dc20881004b 100644 --- a/net/ipv4/netfilter/ip_conntrack_amanda.c +++ b/net/ipv4/netfilter/ip_conntrack_amanda.c @@ -108,6 +108,7 @@ static int help(struct sk_buff **pskb, } exp->expectfn = NULL; + exp->flags = 0; exp->tuple.src.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip; exp->tuple.src.u.tcp.port = 0; diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c index a0648600190..19cba16e6e1 100644 --- a/net/ipv4/netfilter/ip_conntrack_core.c +++ b/net/ipv4/netfilter/ip_conntrack_core.c @@ -197,7 +197,7 @@ ip_ct_invert_tuple(struct ip_conntrack_tuple *inverse, /* ip_conntrack_expect helper functions */ -static void unlink_expect(struct ip_conntrack_expect *exp) +void ip_ct_unlink_expect(struct ip_conntrack_expect *exp) { ASSERT_WRITE_LOCK(&ip_conntrack_lock); IP_NF_ASSERT(!timer_pending(&exp->timeout)); @@ -207,18 +207,12 @@ static void unlink_expect(struct ip_conntrack_expect *exp) ip_conntrack_expect_put(exp); } -void __ip_ct_expect_unlink_destroy(struct ip_conntrack_expect *exp) -{ - unlink_expect(exp); - ip_conntrack_expect_put(exp); -} - static void expectation_timed_out(unsigned long ul_expect) { struct ip_conntrack_expect *exp = (void *)ul_expect; write_lock_bh(&ip_conntrack_lock); - unlink_expect(exp); + ip_ct_unlink_expect(exp); write_unlock_bh(&ip_conntrack_lock); ip_conntrack_expect_put(exp); } @@ -264,10 +258,14 @@ find_expectation(const struct ip_conntrack_tuple *tuple) master ct never got confirmed, we'd hold a reference to it and weird things would happen to future packets). */ if (ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask) - && is_confirmed(i->master) - && del_timer(&i->timeout)) { - unlink_expect(i); - return i; + && is_confirmed(i->master)) { + if (i->flags & IP_CT_EXPECT_PERMANENT) { + atomic_inc(&i->use); + return i; + } else if (del_timer(&i->timeout)) { + ip_ct_unlink_expect(i); + return i; + } } } return NULL; @@ -284,7 +282,7 @@ void ip_ct_remove_expectations(struct ip_conntrack *ct) list_for_each_entry_safe(i, tmp, &ip_conntrack_expect_list, list) { if (i->master == ct && del_timer(&i->timeout)) { - unlink_expect(i); + ip_ct_unlink_expect(i); ip_conntrack_expect_put(i); } } @@ -925,7 +923,7 @@ void ip_conntrack_unexpect_related(struct ip_conntrack_expect *exp) /* choose the the oldest expectation to evict */ list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { if (expect_matches(i, exp) && del_timer(&i->timeout)) { - unlink_expect(i); + ip_ct_unlink_expect(i); write_unlock_bh(&ip_conntrack_lock); ip_conntrack_expect_put(i); return; @@ -934,6 +932,9 @@ void ip_conntrack_unexpect_related(struct ip_conntrack_expect *exp) write_unlock_bh(&ip_conntrack_lock); } +/* We don't increase the master conntrack refcount for non-fulfilled + * conntracks. During the conntrack destruction, the expectations are + * always killed before the conntrack itself */ struct ip_conntrack_expect *ip_conntrack_expect_alloc(struct ip_conntrack *me) { struct ip_conntrack_expect *new; @@ -944,17 +945,14 @@ struct ip_conntrack_expect *ip_conntrack_expect_alloc(struct ip_conntrack *me) return NULL; } new->master = me; - atomic_inc(&new->master->ct_general.use); atomic_set(&new->use, 1); return new; } void ip_conntrack_expect_put(struct ip_conntrack_expect *exp) { - if (atomic_dec_and_test(&exp->use)) { - ip_conntrack_put(exp->master); + if (atomic_dec_and_test(&exp->use)) kmem_cache_free(ip_conntrack_expect_cachep, exp); - } } static void ip_conntrack_expect_insert(struct ip_conntrack_expect *exp) @@ -982,7 +980,7 @@ static void evict_oldest_expect(struct ip_conntrack *master) list_for_each_entry_reverse(i, &ip_conntrack_expect_list, list) { if (i->master == master) { if (del_timer(&i->timeout)) { - unlink_expect(i); + ip_ct_unlink_expect(i); ip_conntrack_expect_put(i); } break; @@ -1099,7 +1097,7 @@ void ip_conntrack_helper_unregister(struct ip_conntrack_helper *me) /* Get rid of expectations */ list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list, list) { if (exp->master->helper == me && del_timer(&exp->timeout)) { - unlink_expect(exp); + ip_ct_unlink_expect(exp); ip_conntrack_expect_put(exp); } } diff --git a/net/ipv4/netfilter/ip_conntrack_ftp.c b/net/ipv4/netfilter/ip_conntrack_ftp.c index 3a2627db172..1b79ec36085 100644 --- a/net/ipv4/netfilter/ip_conntrack_ftp.c +++ b/net/ipv4/netfilter/ip_conntrack_ftp.c @@ -421,6 +421,7 @@ static int help(struct sk_buff **pskb, { 0xFFFFFFFF, { .tcp = { 0xFFFF } }, 0xFF }}); exp->expectfn = NULL; + exp->flags = 0; /* Now, NAT might want to mangle the packet, and register the * (possibly changed) expectation itself. */ diff --git a/net/ipv4/netfilter/ip_conntrack_irc.c b/net/ipv4/netfilter/ip_conntrack_irc.c index 25438eec21a..d7a8a98c05e 100644 --- a/net/ipv4/netfilter/ip_conntrack_irc.c +++ b/net/ipv4/netfilter/ip_conntrack_irc.c @@ -221,6 +221,7 @@ static int help(struct sk_buff **pskb, { { 0, { 0 } }, { 0xFFFFFFFF, { .tcp = { 0xFFFF } }, 0xFF }}); exp->expectfn = NULL; + exp->flags = 0; if (ip_nat_irc_hook) ret = ip_nat_irc_hook(pskb, ctinfo, addr_beg_p - ib_ptr, diff --git a/net/ipv4/netfilter/ip_conntrack_netbios_ns.c b/net/ipv4/netfilter/ip_conntrack_netbios_ns.c new file mode 100644 index 00000000000..2b5cf9c5130 --- /dev/null +++ b/net/ipv4/netfilter/ip_conntrack_netbios_ns.c @@ -0,0 +1,131 @@ +/* + * NetBIOS name service broadcast connection tracking helper + * + * (c) 2005 Patrick McHardy <kaber@trash.net> + * + * 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. + */ +/* + * This helper tracks locally originating NetBIOS name service + * requests by issuing permanent expectations (valid until + * timing out) matching all reply connections from the + * destination network. The only NetBIOS specific thing is + * actually the port number. + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/inetdevice.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/udp.h> +#include <net/route.h> + +#include <linux/netfilter.h> +#include <linux/netfilter_ipv4.h> +#include <linux/netfilter_ipv4/ip_conntrack.h> +#include <linux/netfilter_ipv4/ip_conntrack_helper.h> + +MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); +MODULE_DESCRIPTION("NetBIOS name service broadcast connection tracking helper"); +MODULE_LICENSE("GPL"); + +static unsigned int timeout = 3; +module_param(timeout, int, 0600); +MODULE_PARM_DESC(timeout, "timeout for master connection/replies in seconds"); + +static int help(struct sk_buff **pskb, + struct ip_conntrack *ct, enum ip_conntrack_info ctinfo) +{ + struct ip_conntrack_expect *exp; + struct iphdr *iph = (*pskb)->nh.iph; + struct udphdr _uh, *uh; + struct rtable *rt = (struct rtable *)(*pskb)->dst; + struct in_device *in_dev; + u_int32_t mask = 0; + + /* we're only interested in locally generated packets */ + if ((*pskb)->sk == NULL) + goto out; + if (rt == NULL || !(rt->rt_flags & RTCF_BROADCAST)) + goto out; + if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) + goto out; + + rcu_read_lock(); + in_dev = __in_dev_get(rt->u.dst.dev); + if (in_dev != NULL) { + for_primary_ifa(in_dev) { + if (ifa->ifa_broadcast == iph->daddr) { + mask = ifa->ifa_mask; + break; + } + } endfor_ifa(in_dev); + } + rcu_read_unlock(); + + if (mask == 0) + goto out; + + uh = skb_header_pointer(*pskb, iph->ihl * 4, sizeof(_uh), &_uh); + BUG_ON(uh == NULL); + + exp = ip_conntrack_expect_alloc(ct); + if (exp == NULL) + goto out; + memset(&exp->tuple, 0, sizeof(exp->tuple)); + exp->tuple.src.ip = iph->daddr & mask; + exp->tuple.dst.ip = iph->saddr; + exp->tuple.dst.u.udp.port = uh->source; + exp->tuple.dst.protonum = IPPROTO_UDP; + + memset(&exp->mask, 0, sizeof(exp->mask)); + exp->mask.src.ip = mask; + exp->mask.dst.ip = 0xFFFFFFFF; + exp->mask.dst.u.udp.port = 0xFFFF; + exp->mask.dst.protonum = 0xFF; + + exp->expectfn = NULL; + exp->flags = IP_CT_EXPECT_PERMANENT; + + ip_conntrack_expect_related(exp); + ip_conntrack_expect_put(exp); + + ip_ct_refresh_acct(ct, ctinfo, NULL, timeout * HZ); +out: + return NF_ACCEPT; +} + +static struct ip_conntrack_helper helper = { + .name = "netbios-ns", + .tuple = { + .src.u.udp.port = __constant_htons(137), + .dst.protonum = IPPROTO_UDP, + }, + .mask = { + .src.u.udp.port = 0xFFFF, + .dst.protonum = 0xFF, + }, + .max_expected = 1, + .me = THIS_MODULE, + .help = help, +}; + +static int __init init(void) +{ + helper.timeout = timeout; + return ip_conntrack_helper_register(&helper); +} + +static void __exit fini(void) +{ + ip_conntrack_helper_unregister(&helper); +} + +module_init(init); +module_exit(fini); diff --git a/net/ipv4/netfilter/ip_conntrack_netlink.c b/net/ipv4/netfilter/ip_conntrack_netlink.c index a4e9278db4e..15aef356474 100644 --- a/net/ipv4/netfilter/ip_conntrack_netlink.c +++ b/net/ipv4/netfilter/ip_conntrack_netlink.c @@ -1349,8 +1349,10 @@ ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb, list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list, list) { if (exp->master->helper == h - && del_timer(&exp->timeout)) - __ip_ct_expect_unlink_destroy(exp); + && del_timer(&exp->timeout)) { + ip_ct_unlink_expect(exp); + ip_conntrack_expect_put(exp); + } } write_unlock(&ip_conntrack_lock); } else { @@ -1358,8 +1360,10 @@ ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb, write_lock_bh(&ip_conntrack_lock); list_for_each_entry_safe(exp, tmp, &ip_conntrack_expect_list, list) { - if (del_timer(&exp->timeout)) - __ip_ct_expect_unlink_destroy(exp); + if (del_timer(&exp->timeout)) { + ip_ct_unlink_expect(exp); + ip_conntrack_expect_put(exp); + } } write_unlock_bh(&ip_conntrack_lock); } @@ -1413,6 +1417,7 @@ ctnetlink_create_expect(struct nfattr *cda[]) } exp->expectfn = NULL; + exp->flags = 0; exp->master = ct; memcpy(&exp->tuple, &tuple, sizeof(struct ip_conntrack_tuple)); memcpy(&exp->mask, &mask, sizeof(struct ip_conntrack_tuple)); diff --git a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c index f23ef1f88c4..1985abc59d2 100644 --- a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c +++ b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c @@ -349,6 +349,7 @@ static int tcp_to_nfattr(struct sk_buff *skb, struct nfattr *nfa, return 0; nfattr_failure: + read_unlock_bh(&tcp_lock); return -1; } #endif diff --git a/net/ipv4/netfilter/ip_conntrack_standalone.c b/net/ipv4/netfilter/ip_conntrack_standalone.c index ee5895afd0c..ae3e3e655db 100644 --- a/net/ipv4/netfilter/ip_conntrack_standalone.c +++ b/net/ipv4/netfilter/ip_conntrack_standalone.c @@ -998,7 +998,7 @@ EXPORT_SYMBOL(ip_conntrack_expect_related); EXPORT_SYMBOL(ip_conntrack_unexpect_related); EXPORT_SYMBOL_GPL(ip_conntrack_expect_list); EXPORT_SYMBOL_GPL(__ip_conntrack_expect_find); -EXPORT_SYMBOL_GPL(__ip_ct_expect_unlink_destroy); +EXPORT_SYMBOL_GPL(ip_ct_unlink_expect); EXPORT_SYMBOL(ip_conntrack_tuple_taken); EXPORT_SYMBOL(ip_ct_gather_frags); diff --git a/net/ipv4/netfilter/ip_conntrack_tftp.c b/net/ipv4/netfilter/ip_conntrack_tftp.c index f8ff170f390..d2b59053345 100644 --- a/net/ipv4/netfilter/ip_conntrack_tftp.c +++ b/net/ipv4/netfilter/ip_conntrack_tftp.c @@ -75,6 +75,7 @@ static int tftp_help(struct sk_buff **pskb, exp->mask.dst.u.udp.port = 0xffff; exp->mask.dst.protonum = 0xff; exp->expectfn = NULL; + exp->flags = 0; DEBUGP("expect: "); DUMP_TUPLE(&exp->tuple); diff --git a/net/ipv4/netfilter/ip_nat_rule.c b/net/ipv4/netfilter/ip_nat_rule.c index 60d70fa41a1..cb66b8bddeb 100644 --- a/net/ipv4/netfilter/ip_nat_rule.c +++ b/net/ipv4/netfilter/ip_nat_rule.c @@ -255,6 +255,27 @@ alloc_null_binding(struct ip_conntrack *conntrack, return ip_nat_setup_info(conntrack, &range, hooknum); } +unsigned int +alloc_null_binding_confirmed(struct ip_conntrack *conntrack, + struct ip_nat_info *info, + unsigned int hooknum) +{ + u_int32_t ip + = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC + ? conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip + : conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip); + u_int16_t all + = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC + ? conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.all + : conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.src.u.all); + struct ip_nat_range range + = { IP_NAT_RANGE_MAP_IPS, ip, ip, { all }, { all } }; + + DEBUGP("Allocating NULL binding for confirmed %p (%u.%u.%u.%u)\n", + conntrack, NIPQUAD(ip)); + return ip_nat_setup_info(conntrack, &range, hooknum); +} + int ip_nat_rule_find(struct sk_buff **pskb, unsigned int hooknum, const struct net_device *in, diff --git a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c index 89db052add8..0ff368b131f 100644 --- a/net/ipv4/netfilter/ip_nat_standalone.c +++ b/net/ipv4/netfilter/ip_nat_standalone.c @@ -123,8 +123,12 @@ ip_nat_fn(unsigned int hooknum, if (!ip_nat_initialized(ct, maniptype)) { unsigned int ret; - /* LOCAL_IN hook doesn't have a chain! */ - if (hooknum == NF_IP_LOCAL_IN) + if (unlikely(is_confirmed(ct))) + /* NAT module was loaded late */ + ret = alloc_null_binding_confirmed(ct, info, + hooknum); + else if (hooknum == NF_IP_LOCAL_IN) + /* LOCAL_IN hook doesn't have a chain! */ ret = alloc_null_binding(ct, info, hooknum); else ret = ip_nat_rule_find(pskb, hooknum, |