diff options
| -rw-r--r-- | include/net/netfilter/nf_conntrack_extend.h | 4 | ||||
| -rw-r--r-- | include/net/netfilter/nf_conntrack_labels.h | 55 | ||||
| -rw-r--r-- | include/net/netns/conntrack.h | 4 | ||||
| -rw-r--r-- | include/uapi/linux/netfilter/xt_connlabel.h | 12 | ||||
| -rw-r--r-- | net/netfilter/Kconfig | 18 | ||||
| -rw-r--r-- | net/netfilter/Makefile | 2 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 12 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_labels.c | 72 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_netlink.c | 3 | ||||
| -rw-r--r-- | net/netfilter/xt_connlabel.c | 99 |
10 files changed, 281 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_conntrack_extend.h b/include/net/netfilter/nf_conntrack_extend.h index 8b4d1fc2909..977bc8a4644 100644 --- a/include/net/netfilter/nf_conntrack_extend.h +++ b/include/net/netfilter/nf_conntrack_extend.h @@ -23,6 +23,9 @@ enum nf_ct_ext_id { #ifdef CONFIG_NF_CONNTRACK_TIMEOUT NF_CT_EXT_TIMEOUT, #endif +#ifdef CONFIG_NF_CONNTRACK_LABELS + NF_CT_EXT_LABELS, +#endif NF_CT_EXT_NUM, }; @@ -33,6 +36,7 @@ enum nf_ct_ext_id { #define NF_CT_EXT_ZONE_TYPE struct nf_conntrack_zone #define NF_CT_EXT_TSTAMP_TYPE struct nf_conn_tstamp #define NF_CT_EXT_TIMEOUT_TYPE struct nf_conn_timeout +#define NF_CT_EXT_LABELS_TYPE struct nf_conn_labels /* Extensions: optional stuff which isn't permanently in struct. */ struct nf_ct_ext { diff --git a/include/net/netfilter/nf_conntrack_labels.h b/include/net/netfilter/nf_conntrack_labels.h new file mode 100644 index 00000000000..b94fe31c7b3 --- /dev/null +++ b/include/net/netfilter/nf_conntrack_labels.h @@ -0,0 +1,55 @@ +#include <linux/types.h> +#include <net/net_namespace.h> +#include <linux/netfilter/nf_conntrack_common.h> +#include <linux/netfilter/nf_conntrack_tuple_common.h> +#include <net/netfilter/nf_conntrack.h> +#include <net/netfilter/nf_conntrack_extend.h> + +#include <uapi/linux/netfilter/xt_connlabel.h> + +struct nf_conn_labels { + u8 words; + unsigned long bits[]; +}; + +static inline struct nf_conn_labels *nf_ct_labels_find(const struct nf_conn *ct) +{ +#ifdef CONFIG_NF_CONNTRACK_LABELS + return nf_ct_ext_find(ct, NF_CT_EXT_LABELS); +#else + return NULL; +#endif +} + +static inline struct nf_conn_labels *nf_ct_labels_ext_add(struct nf_conn *ct) +{ +#ifdef CONFIG_NF_CONNTRACK_LABELS + struct nf_conn_labels *cl_ext; + struct net *net = nf_ct_net(ct); + u8 words; + + words = ACCESS_ONCE(net->ct.label_words); + if (words == 0 || WARN_ON_ONCE(words > 8)) + return NULL; + + cl_ext = nf_ct_ext_add_length(ct, NF_CT_EXT_LABELS, + words * sizeof(long), GFP_ATOMIC); + if (cl_ext != NULL) + cl_ext->words = words; + + return cl_ext; +#else + return NULL; +#endif +} + +bool nf_connlabel_match(const struct nf_conn *ct, u16 bit); +int nf_connlabel_set(struct nf_conn *ct, u16 bit); + +#ifdef CONFIG_NF_CONNTRACK_LABELS +int nf_conntrack_labels_init(struct net *net); +void nf_conntrack_labels_fini(struct net *net); +#else +static inline int nf_conntrack_labels_init(struct net *n) { return 0; } +static inline void nf_conntrack_labels_fini(struct net *net) {} +#endif diff --git a/include/net/netns/conntrack.h b/include/net/netns/conntrack.h index 923cb20051e..c9c0c538b68 100644 --- a/include/net/netns/conntrack.h +++ b/include/net/netns/conntrack.h @@ -84,6 +84,10 @@ struct netns_ct { int sysctl_auto_assign_helper; bool auto_assign_helper_warned; struct nf_ip_net nf_ct_proto; +#if defined(CONFIG_NF_CONNTRACK_LABELS) + unsigned int labels_used; + u8 label_words; +#endif #ifdef CONFIG_NF_NAT_NEEDED struct hlist_head *nat_bysource; unsigned int nat_htable_size; diff --git a/include/uapi/linux/netfilter/xt_connlabel.h b/include/uapi/linux/netfilter/xt_connlabel.h new file mode 100644 index 00000000000..c4bc9ee9b33 --- /dev/null +++ b/include/uapi/linux/netfilter/xt_connlabel.h @@ -0,0 +1,12 @@ +#include <linux/types.h> + +#define XT_CONNLABEL_MAXBIT 127 +enum xt_connlabel_mtopts { + XT_CONNLABEL_OP_INVERT = 1 << 0, + XT_CONNLABEL_OP_SET = 1 << 1, +}; + +struct xt_connlabel_mtinfo { + __u16 bit; + __u16 options; +}; diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 49e96df5fbc..bb48607d4ee 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -124,6 +124,12 @@ config NF_CONNTRACK_TIMESTAMP If unsure, say `N'. +config NF_CONNTRACK_LABELS + bool + help + This option enables support for assigning user-defined flag bits + to connection tracking entries. It selected by the connlabel match. + config NF_CT_PROTO_DCCP tristate 'DCCP protocol connection tracking support (EXPERIMENTAL)' depends on EXPERIMENTAL @@ -842,6 +848,18 @@ config NETFILTER_XT_MATCH_CONNBYTES If you want to compile it as a module, say M here and read <file:Documentation/kbuild/modules.txt>. If unsure, say `N'. +config NETFILTER_XT_MATCH_CONNLABEL + tristate '"connlabel" match support' + select NF_CONNTRACK_LABELS + depends on NETFILTER_ADVANCED + ---help--- + This match allows you to test and assign userspace-defined labels names + to a connection. The kernel only stores bit values - mapping + names to bits is done by userspace. + + Unlike connmark, more than 32 flag bits may be assigned to a + connection simultaneously. + config NETFILTER_XT_MATCH_CONNLIMIT tristate '"connlimit" match support"' depends on NF_CONNTRACK diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 32596978df1..b3bbda60945 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -4,6 +4,7 @@ nf_conntrack-y := nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_exp nf_conntrack-$(CONFIG_NF_CONNTRACK_TIMEOUT) += nf_conntrack_timeout.o nf_conntrack-$(CONFIG_NF_CONNTRACK_TIMESTAMP) += nf_conntrack_timestamp.o nf_conntrack-$(CONFIG_NF_CONNTRACK_EVENTS) += nf_conntrack_ecache.o +nf_conntrack-$(CONFIG_NF_CONNTRACK_LABELS) += nf_conntrack_labels.o obj-$(CONFIG_NETFILTER) = netfilter.o @@ -101,6 +102,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_ADDRTYPE) += xt_addrtype.o obj-$(CONFIG_NETFILTER_XT_MATCH_CLUSTER) += xt_cluster.o obj-$(CONFIG_NETFILTER_XT_MATCH_COMMENT) += xt_comment.o obj-$(CONFIG_NETFILTER_XT_MATCH_CONNBYTES) += xt_connbytes.o +obj-$(CONFIG_NETFILTER_XT_MATCH_CONNLABEL) += xt_connlabel.o obj-$(CONFIG_NETFILTER_XT_MATCH_CONNLIMIT) += xt_connlimit.o obj-$(CONFIG_NETFILTER_XT_MATCH_CONNTRACK) += xt_conntrack.o obj-$(CONFIG_NETFILTER_XT_MATCH_CPU) += xt_cpu.o diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index e4a0c4fb3a7..85aa4b7149c 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -45,6 +45,7 @@ #include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/nf_conntrack_timestamp.h> #include <net/netfilter/nf_conntrack_timeout.h> +#include <net/netfilter/nf_conntrack_labels.h> #include <net/netfilter/nf_nat.h> #include <net/netfilter/nf_nat_core.h> @@ -763,6 +764,7 @@ void nf_conntrack_free(struct nf_conn *ct) } EXPORT_SYMBOL_GPL(nf_conntrack_free); + /* Allocate a new conntrack: we return -ENOMEM if classification failed due to stress. Otherwise it really is unclassifiable. */ static struct nf_conntrack_tuple_hash * @@ -809,6 +811,7 @@ init_conntrack(struct net *net, struct nf_conn *tmpl, nf_ct_acct_ext_add(ct, GFP_ATOMIC); nf_ct_tstamp_ext_add(ct, GFP_ATOMIC); + nf_ct_labels_ext_add(ct); ecache = tmpl ? nf_ct_ecache_find(tmpl) : NULL; nf_ct_ecache_ext_add(ct, ecache ? ecache->ctmask : 0, @@ -1352,6 +1355,7 @@ static void nf_conntrack_cleanup_net(struct net *net) } nf_ct_free_hashtable(net->ct.hash, net->ct.htable_size); + nf_conntrack_labels_fini(net); nf_conntrack_helper_fini(net); nf_conntrack_timeout_fini(net); nf_conntrack_ecache_fini(net); @@ -1583,7 +1587,15 @@ static int nf_conntrack_init_net(struct net *net) ret = nf_conntrack_helper_init(net); if (ret < 0) goto err_helper; + + ret = nf_conntrack_labels_init(net); + if (ret < 0) + goto err_labels; + return 0; + +err_labels: + nf_conntrack_helper_fini(net); err_helper: nf_conntrack_timeout_fini(net); err_timeout: diff --git a/net/netfilter/nf_conntrack_labels.c b/net/netfilter/nf_conntrack_labels.c new file mode 100644 index 00000000000..0c542f41f33 --- /dev/null +++ b/net/netfilter/nf_conntrack_labels.c @@ -0,0 +1,72 @@ +/* + * test/set flag bits stored in conntrack extension area. + * + * (C) 2013 Astaro GmbH & Co KG + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/ctype.h> +#include <linux/export.h> +#include <linux/jhash.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <linux/slab.h> + +#include <net/netfilter/nf_conntrack_ecache.h> +#include <net/netfilter/nf_conntrack_labels.h> + +static unsigned int label_bits(const struct nf_conn_labels *l) +{ + unsigned int longs = l->words; + return longs * BITS_PER_LONG; +} + +bool nf_connlabel_match(const struct nf_conn *ct, u16 bit) +{ + struct nf_conn_labels *labels = nf_ct_labels_find(ct); + + if (!labels) + return false; + + return bit < label_bits(labels) && test_bit(bit, labels->bits); +} +EXPORT_SYMBOL_GPL(nf_connlabel_match); + +int nf_connlabel_set(struct nf_conn *ct, u16 bit) +{ + struct nf_conn_labels *labels = nf_ct_labels_find(ct); + + if (!labels || bit >= label_bits(labels)) + return -ENOSPC; + + if (test_bit(bit, labels->bits)) + return 0; + + if (test_and_set_bit(bit, labels->bits)) + return 0; + + return 0; +} +EXPORT_SYMBOL_GPL(nf_connlabel_set); + +static struct nf_ct_ext_type labels_extend __read_mostly = { + .len = sizeof(struct nf_conn_labels), + .align = __alignof__(struct nf_conn_labels), + .id = NF_CT_EXT_LABELS, +}; + +int nf_conntrack_labels_init(struct net *net) +{ + if (net_eq(net, &init_net)) + return nf_ct_extend_register(&labels_extend); + return 0; +} + +void nf_conntrack_labels_fini(struct net *net) +{ + if (net_eq(net, &init_net)) + nf_ct_extend_unregister(&labels_extend); +} diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 627b0e50b23..e0b10ee180e 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -43,6 +43,7 @@ #include <net/netfilter/nf_conntrack_acct.h> #include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/nf_conntrack_timestamp.h> +#include <net/netfilter/nf_conntrack_labels.h> #ifdef CONFIG_NF_NAT_NEEDED #include <net/netfilter/nf_nat_core.h> #include <net/netfilter/nf_nat_l4proto.h> @@ -1598,6 +1599,8 @@ ctnetlink_create_conntrack(struct net *net, u16 zone, nf_ct_acct_ext_add(ct, GFP_ATOMIC); nf_ct_tstamp_ext_add(ct, GFP_ATOMIC); nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC); + nf_ct_labels_ext_add(ct); + /* we must add conntrack extensions before confirmation. */ ct->status |= IPS_CONFIRMED; diff --git a/net/netfilter/xt_connlabel.c b/net/netfilter/xt_connlabel.c new file mode 100644 index 00000000000..9f8719df200 --- /dev/null +++ b/net/netfilter/xt_connlabel.c @@ -0,0 +1,99 @@ +/* + * (C) 2013 Astaro GmbH & Co KG + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/skbuff.h> +#include <net/netfilter/nf_conntrack.h> +#include <net/netfilter/nf_conntrack_labels.h> +#include <linux/netfilter/x_tables.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); +MODULE_DESCRIPTION("Xtables: add/match connection trackling labels"); +MODULE_ALIAS("ipt_connlabel"); +MODULE_ALIAS("ip6t_connlabel"); + +static bool +connlabel_mt(const struct sk_buff *skb, struct xt_action_param *par) +{ + const struct xt_connlabel_mtinfo *info = par->matchinfo; + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + bool invert = info->options & XT_CONNLABEL_OP_INVERT; + + ct = nf_ct_get(skb, &ctinfo); + if (ct == NULL || nf_ct_is_untracked(ct)) + return invert; + + if (info->options & XT_CONNLABEL_OP_SET) + return (nf_connlabel_set(ct, info->bit) == 0) ^ invert; + + return nf_connlabel_match(ct, info->bit) ^ invert; +} + +static int connlabel_mt_check(const struct xt_mtchk_param *par) +{ + const int options = XT_CONNLABEL_OP_INVERT | + XT_CONNLABEL_OP_SET; + struct xt_connlabel_mtinfo *info = par->matchinfo; + int ret; + size_t words; + + if (info->bit > XT_CONNLABEL_MAXBIT) + return -ERANGE; + + if (info->options & ~options) { + pr_err("Unknown options in mask %x\n", info->options); + return -EINVAL; + } + + ret = nf_ct_l3proto_try_module_get(par->family); + if (ret < 0) { + pr_info("cannot load conntrack support for proto=%u\n", + par->family); + return ret; + } + + par->net->ct.labels_used++; + words = BITS_TO_LONGS(info->bit+1); + if (words > par->net->ct.label_words) + par->net->ct.label_words = words; + + return ret; +} + +static void connlabel_mt_destroy(const struct xt_mtdtor_param *par) +{ + par->net->ct.labels_used--; + if (par->net->ct.labels_used == 0) + par->net->ct.label_words = 0; + nf_ct_l3proto_module_put(par->family); +} + +static struct xt_match connlabels_mt_reg __read_mostly = { + .name = "connlabel", + .family = NFPROTO_UNSPEC, + .checkentry = connlabel_mt_check, + .match = connlabel_mt, + .matchsize = sizeof(struct xt_connlabel_mtinfo), + .destroy = connlabel_mt_destroy, + .me = THIS_MODULE, +}; + +static int __init connlabel_mt_init(void) +{ + return xt_register_match(&connlabels_mt_reg); +} + +static void __exit connlabel_mt_exit(void) +{ + xt_unregister_match(&connlabels_mt_reg); +} + +module_init(connlabel_mt_init); +module_exit(connlabel_mt_exit); |