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netfilter: ctnetlink: add kernel side filtering for dump

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Conntrack dump does not support kernel side filtering (only get exists,
but it returns only one entry. And user has to give a full valid tuple)

It means that userspace has to implement filtering after receiving many
irrelevant entries, consuming resources (conntrack table is sometimes
very huge, much more than a routing table for example).

This patch adds filtering in kernel side. To achieve this goal, we:

 * Add a new CTA_FILTER netlink attributes, actually a flag list to
   parametize filtering
 * Convert some *nlattr_to_tuple() functions, to allow a partial parsing
   of CTA_TUPLE_ORIG and CTA_TUPLE_REPLY (so nf_conntrack_tuple it not
   fully set)

Filtering is now possible on:
 * IP SRC/DST values
 * Ports for TCP and UDP flows
 * IMCP(v6) codes types and IDs

Filtering is done as an "AND" operator. For example, when flags
PROTO_SRC_PORT, PROTO_NUM and IP_SRC are sets, only entries matching all
values are dumped.

Changes since v1:
  Set NLM_F_DUMP_FILTERED in nlm flags if entries are filtered

Changes since v2:
  Move several constants to nf_internals.h
  Move a fix on netlink values check in a separate patch
  Add a check on not-supported flags
  Return EOPNOTSUPP if CDA_FILTER is set in ctnetlink_flush_conntrack
  (not yet implemented)
  Code style issues

Changes since v3:
  Fix compilation warning reported by kbuild test robot

Changes since v4:
  Fix a regression introduced in v3 (returned EINVAL for valid netlink
  messages without CTA_MARK)

Changes since v5:
  Change definition of CTA_FILTER_F_ALL
  Fix a regression when CTA_TUPLE_ZONE is not set

Signed-off-by: Romain Bellan <romain.bellan@wifirst.fr>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Romain Bellan 2020-05-04 21:34:29 +02:00 committed by Pablo Neira Ayuso
parent 626a83238e
commit cb8aa9a3af
7 changed files with 390 additions and 69 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/net/netfilter/nf_conntrack_l4proto.h
View File

@ -42,7 +42,8 @@ struct nf_conntrack_l4proto {
/* Calculate tuple nlattr size */ /* Calculate tuple nlattr size */
unsigned int (*nlattr_tuple_size)(void); unsigned int (*nlattr_tuple_size)(void);
int (*nlattr_to_tuple)(struct nlattr *tb[], int (*nlattr_to_tuple)(struct nlattr *tb[],
struct nf_conntrack_tuple *t); struct nf_conntrack_tuple *t,
u_int32_t flags);
const struct nla_policy *nla_policy; const struct nla_policy *nla_policy;
struct { struct {
@ -152,7 +153,8 @@ const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto);
int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb, int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
const struct nf_conntrack_tuple *tuple); const struct nf_conntrack_tuple *tuple);
int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *t); struct nf_conntrack_tuple *t,
u_int32_t flags);
unsigned int nf_ct_port_nlattr_tuple_size(void); unsigned int nf_ct_port_nlattr_tuple_size(void);
extern const struct nla_policy nf_ct_port_nla_policy[]; extern const struct nla_policy nf_ct_port_nla_policy[];

9
include/uapi/linux/netfilter/nfnetlink_conntrack.h
View File

@ -55,6 +55,7 @@ enum ctattr_type {
CTA_LABELS, CTA_LABELS,
CTA_LABELS_MASK, CTA_LABELS_MASK,
CTA_SYNPROXY, CTA_SYNPROXY,
CTA_FILTER,
__CTA_MAX __CTA_MAX
}; };
#define CTA_MAX (__CTA_MAX - 1) #define CTA_MAX (__CTA_MAX - 1)
@ -276,4 +277,12 @@ enum ctattr_expect_stats {
}; };
#define CTA_STATS_EXP_MAX (__CTA_STATS_EXP_MAX - 1) #define CTA_STATS_EXP_MAX (__CTA_STATS_EXP_MAX - 1)
enum ctattr_filter {
CTA_FILTER_UNSPEC,
CTA_FILTER_ORIG_FLAGS,
CTA_FILTER_REPLY_FLAGS,
__CTA_FILTER_MAX
};
#define CTA_FILTER_MAX (__CTA_FILTER_MAX - 1)
#endif /* _IPCONNTRACK_NETLINK_H */ #endif /* _IPCONNTRACK_NETLINK_H */

13
net/netfilter/nf_conntrack_core.c
View File

@ -1974,13 +1974,22 @@ const struct nla_policy nf_ct_port_nla_policy[CTA_PROTO_MAX+1] = {
EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy); EXPORT_SYMBOL_GPL(nf_ct_port_nla_policy);
int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[], int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *t) struct nf_conntrack_tuple *t,
u_int32_t flags)
{ {
if (!tb[CTA_PROTO_SRC_PORT] || !tb[CTA_PROTO_DST_PORT]) if (flags & CTA_FILTER_FLAG(CTA_PROTO_SRC_PORT)) {
if (!tb[CTA_PROTO_SRC_PORT])
return -EINVAL; return -EINVAL;
t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]); t->src.u.tcp.port = nla_get_be16(tb[CTA_PROTO_SRC_PORT]);
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_DST_PORT)) {
if (!tb[CTA_PROTO_DST_PORT])
return -EINVAL;
t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]); t->dst.u.tcp.port = nla_get_be16(tb[CTA_PROTO_DST_PORT]);
}
return 0; return 0;
} }

306
net/netfilter/nf_conntrack_netlink.c
View File

@ -54,6 +54,8 @@
#include <linux/netfilter/nfnetlink.h> #include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_conntrack.h> #include <linux/netfilter/nfnetlink_conntrack.h>
#include "nf_internals.h"
MODULE_LICENSE("GPL"); MODULE_LICENSE("GPL");
static int ctnetlink_dump_tuples_proto(struct sk_buff *skb, static int ctnetlink_dump_tuples_proto(struct sk_buff *skb,
@ -544,14 +546,16 @@ static int ctnetlink_dump_info(struct sk_buff *skb, struct nf_conn *ct)
static int static int
ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type, ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
struct nf_conn *ct, bool extinfo) struct nf_conn *ct, bool extinfo, unsigned int flags)
{ {
const struct nf_conntrack_zone *zone; const struct nf_conntrack_zone *zone;
struct nlmsghdr *nlh; struct nlmsghdr *nlh;
struct nfgenmsg *nfmsg; struct nfgenmsg *nfmsg;
struct nlattr *nest_parms; struct nlattr *nest_parms;
unsigned int flags = portid ? NLM_F_MULTI : 0, event; unsigned int event;
if (portid)
flags |= NLM_F_MULTI;
event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW); event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW);
nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags); nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
if (nlh == NULL) if (nlh == NULL)
@ -847,17 +851,70 @@ static int ctnetlink_done(struct netlink_callback *cb)
} }
struct ctnetlink_filter { struct ctnetlink_filter {
u_int32_t cta_flags;
u8 family; u8 family;
u_int32_t orig_flags;
u_int32_t reply_flags;
struct nf_conntrack_tuple orig;
struct nf_conntrack_tuple reply;
struct nf_conntrack_zone zone;
struct { struct {
u_int32_t val; u_int32_t val;
u_int32_t mask; u_int32_t mask;
} mark; } mark;
}; };
static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = {
[CTA_FILTER_ORIG_FLAGS] = { .type = NLA_U32 },
[CTA_FILTER_REPLY_FLAGS] = { .type = NLA_U32 },
};
static int ctnetlink_parse_filter(const struct nlattr *attr,
struct ctnetlink_filter *filter)
{
struct nlattr *tb[CTA_FILTER_MAX + 1];
int ret = 0;
ret = nla_parse_nested(tb, CTA_FILTER_MAX, attr, cta_filter_nla_policy,
NULL);
if (ret)
return ret;
if (tb[CTA_FILTER_ORIG_FLAGS]) {
filter->orig_flags = nla_get_u32(tb[CTA_FILTER_ORIG_FLAGS]);
if (filter->orig_flags & ~CTA_FILTER_F_ALL)
return -EOPNOTSUPP;
}
if (tb[CTA_FILTER_REPLY_FLAGS]) {
filter->reply_flags = nla_get_u32(tb[CTA_FILTER_REPLY_FLAGS]);
if (filter->reply_flags & ~CTA_FILTER_F_ALL)
return -EOPNOTSUPP;
}
return 0;
}
static int ctnetlink_parse_zone(const struct nlattr *attr,
struct nf_conntrack_zone *zone);
static int ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
struct nf_conntrack_tuple *tuple,
u32 type, u_int8_t l3num,
struct nf_conntrack_zone *zone,
u_int32_t flags);
/* applied on filters */
#define CTA_FILTER_F_CTA_MARK (1 << 0)
#define CTA_FILTER_F_CTA_MARK_MASK (1 << 1)
static struct ctnetlink_filter * static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family) ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
{ {
struct ctnetlink_filter *filter; struct ctnetlink_filter *filter;
int err;
#ifndef CONFIG_NF_CONNTRACK_MARK #ifndef CONFIG_NF_CONNTRACK_MARK
if (cda[CTA_MARK] || cda[CTA_MARK_MASK]) if (cda[CTA_MARK] || cda[CTA_MARK_MASK])
@ -871,12 +928,63 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
filter->family = family; filter->family = family;
#ifdef CONFIG_NF_CONNTRACK_MARK #ifdef CONFIG_NF_CONNTRACK_MARK
if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) { if (cda[CTA_MARK]) {
filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK])); filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
filter->cta_flags |= CTA_FILTER_FLAG(CTA_MARK);
if (cda[CTA_MARK_MASK]) {
filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK])); filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
filter->cta_flags |= CTA_FILTER_FLAG(CTA_MARK_MASK);
} else {
filter->mark.mask = 0xffffffff;
}
} else if (cda[CTA_MARK_MASK]) {
return ERR_PTR(-EINVAL);
} }
#endif #endif
if (!cda[CTA_FILTER])
return filter; return filter;
err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
if (err < 0)
return ERR_PTR(err);
err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
if (err < 0)
return ERR_PTR(err);
if (filter->orig_flags) {
if (!cda[CTA_TUPLE_ORIG])
return ERR_PTR(-EINVAL);
err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
CTA_TUPLE_ORIG,
filter->family,
&filter->zone,
filter->orig_flags);
if (err < 0)
return ERR_PTR(err);
}
if (filter->reply_flags) {
if (!cda[CTA_TUPLE_REPLY])
return ERR_PTR(-EINVAL);
err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
CTA_TUPLE_REPLY,
filter->family,
&filter->zone,
filter->orig_flags);
if (err < 0)
return ERR_PTR(err);
}
return filter;
}
static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
{
return family || cda[CTA_MARK] || cda[CTA_FILTER];
} }
static int ctnetlink_start(struct netlink_callback *cb) static int ctnetlink_start(struct netlink_callback *cb)
@ -886,7 +994,7 @@ static int ctnetlink_start(struct netlink_callback *cb)
struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh); struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
u8 family = nfmsg->nfgen_family; u8 family = nfmsg->nfgen_family;
if (family || (cda[CTA_MARK] && cda[CTA_MARK_MASK])) { if (ctnetlink_needs_filter(family, cda)) {
filter = ctnetlink_alloc_filter(cda, family); filter = ctnetlink_alloc_filter(cda, family);
if (IS_ERR(filter)) if (IS_ERR(filter))
return PTR_ERR(filter); return PTR_ERR(filter);
@ -896,9 +1004,79 @@ static int ctnetlink_start(struct netlink_callback *cb)
return 0; return 0;
} }
static int ctnetlink_filter_match_tuple(struct nf_conntrack_tuple *filter_tuple,
struct nf_conntrack_tuple *ct_tuple,
u_int32_t flags, int family)
{
switch (family) {
case NFPROTO_IPV4:
if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
filter_tuple->src.u3.ip != ct_tuple->src.u3.ip)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
filter_tuple->dst.u3.ip != ct_tuple->dst.u3.ip)
return 0;
break;
case NFPROTO_IPV6:
if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
!ipv6_addr_cmp(&filter_tuple->src.u3.in6,
&ct_tuple->src.u3.in6))
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
!ipv6_addr_cmp(&filter_tuple->dst.u3.in6,
&ct_tuple->dst.u3.in6))
return 0;
break;
}
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) &&
filter_tuple->dst.protonum != ct_tuple->dst.protonum)
return 0;
switch (ct_tuple->dst.protonum) {
case IPPROTO_TCP:
case IPPROTO_UDP:
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_SRC_PORT)) &&
filter_tuple->src.u.tcp.port != ct_tuple->src.u.tcp.port)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_DST_PORT)) &&
filter_tuple->dst.u.tcp.port != ct_tuple->dst.u.tcp.port)
return 0;
break;
case IPPROTO_ICMP:
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_TYPE)) &&
filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_CODE)) &&
filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_ID)) &&
filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
return 0;
break;
case IPPROTO_ICMPV6:
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_TYPE)) &&
filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_CODE)) &&
filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
return 0;
if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_ID)) &&
filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
return 0;
break;
}
return 1;
}
static int ctnetlink_filter_match(struct nf_conn *ct, void *data) static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
{ {
struct ctnetlink_filter *filter = data; struct ctnetlink_filter *filter = data;
struct nf_conntrack_tuple *tuple;
if (filter == NULL) if (filter == NULL)
goto out; goto out;
@ -910,8 +1088,28 @@ static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
if (filter->family && nf_ct_l3num(ct) != filter->family) if (filter->family && nf_ct_l3num(ct) != filter->family)
goto ignore_entry; goto ignore_entry;
if (filter->orig_flags) {
tuple = nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL);
if (!ctnetlink_filter_match_tuple(&filter->orig, tuple,
filter->orig_flags,
filter->family))
goto ignore_entry;
}
if (filter->reply_flags) {
tuple = nf_ct_tuple(ct, IP_CT_DIR_REPLY);
if (!ctnetlink_filter_match_tuple(&filter->reply, tuple,
filter->reply_flags,
filter->family))
goto ignore_entry;
}
#ifdef CONFIG_NF_CONNTRACK_MARK #ifdef CONFIG_NF_CONNTRACK_MARK
if ((ct->mark & filter->mark.mask) != filter->mark.val) if ((filter->cta_flags & CTA_FILTER_FLAG(CTA_MARK_MASK)) &&
(ct->mark & filter->mark.mask) != filter->mark.val)
goto ignore_entry;
else if ((filter->cta_flags & CTA_FILTER_FLAG(CTA_MARK)) &&
ct->mark != filter->mark.val)
goto ignore_entry; goto ignore_entry;
#endif #endif
@ -925,6 +1123,7 @@ ignore_entry:
static int static int
ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb) ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
{ {
unsigned int flags = cb->data ? NLM_F_DUMP_FILTERED : 0;
struct net *net = sock_net(skb->sk); struct net *net = sock_net(skb->sk);
struct nf_conn *ct, *last; struct nf_conn *ct, *last;
struct nf_conntrack_tuple_hash *h; struct nf_conntrack_tuple_hash *h;
@ -979,7 +1178,7 @@ restart:
ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid, ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, cb->nlh->nlmsg_seq,
NFNL_MSG_TYPE(cb->nlh->nlmsg_type), NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
ct, true); ct, true, flags);
if (res < 0) { if (res < 0) {
nf_conntrack_get(&ct->ct_general); nf_conntrack_get(&ct->ct_general);
cb->args[1] = (unsigned long)ct; cb->args[1] = (unsigned long)ct;
@ -1014,31 +1213,50 @@ out:
} }
static int ipv4_nlattr_to_tuple(struct nlattr *tb[], static int ipv4_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *t) struct nf_conntrack_tuple *t,
u_int32_t flags)
{ {
if (!tb[CTA_IP_V4_SRC] || !tb[CTA_IP_V4_DST]) if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
if (!tb[CTA_IP_V4_SRC])
return -EINVAL; return -EINVAL;
t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]); t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]);
}
if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
if (!tb[CTA_IP_V4_DST])
return -EINVAL;
t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]); t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]);
}
return 0; return 0;
} }
static int ipv6_nlattr_to_tuple(struct nlattr *tb[], static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *t) struct nf_conntrack_tuple *t,
u_int32_t flags)
{ {
if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST]) if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
if (!tb[CTA_IP_V6_SRC])
return -EINVAL; return -EINVAL;
t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]); t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
}
if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
if (!tb[CTA_IP_V6_DST])
return -EINVAL;
t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]); t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
}
return 0; return 0;
} }
static int ctnetlink_parse_tuple_ip(struct nlattr *attr, static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
struct nf_conntrack_tuple *tuple) struct nf_conntrack_tuple *tuple,
u_int32_t flags)
{ {
struct nlattr *tb[CTA_IP_MAX+1]; struct nlattr *tb[CTA_IP_MAX+1];
int ret = 0; int ret = 0;
@ -1054,10 +1272,10 @@ static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
switch (tuple->src.l3num) { switch (tuple->src.l3num) {
case NFPROTO_IPV4: case NFPROTO_IPV4:
ret = ipv4_nlattr_to_tuple(tb, tuple); ret = ipv4_nlattr_to_tuple(tb, tuple, flags);
break; break;
case NFPROTO_IPV6: case NFPROTO_IPV6:
ret = ipv6_nlattr_to_tuple(tb, tuple); ret = ipv6_nlattr_to_tuple(tb, tuple, flags);
break; break;
} }
@ -1069,7 +1287,8 @@ static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
}; };
static int ctnetlink_parse_tuple_proto(struct nlattr *attr, static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
struct nf_conntrack_tuple *tuple) struct nf_conntrack_tuple *tuple,
u_int32_t flags)
{ {
const struct nf_conntrack_l4proto *l4proto; const struct nf_conntrack_l4proto *l4proto;
struct nlattr *tb[CTA_PROTO_MAX+1]; struct nlattr *tb[CTA_PROTO_MAX+1];
@ -1080,8 +1299,12 @@ static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
if (ret < 0) if (ret < 0)
return ret; return ret;
if (!(flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)))
return 0;
if (!tb[CTA_PROTO_NUM]) if (!tb[CTA_PROTO_NUM])
return -EINVAL; return -EINVAL;
tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]); tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
rcu_read_lock(); rcu_read_lock();
@ -1092,7 +1315,7 @@ static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
l4proto->nla_policy, l4proto->nla_policy,
NULL); NULL);
if (ret == 0) if (ret == 0)
ret = l4proto->nlattr_to_tuple(tb, tuple); ret = l4proto->nlattr_to_tuple(tb, tuple, flags);
} }
rcu_read_unlock(); rcu_read_unlock();
@ -1143,10 +1366,21 @@ static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
[CTA_TUPLE_ZONE] = { .type = NLA_U16 }, [CTA_TUPLE_ZONE] = { .type = NLA_U16 },
}; };
#define CTA_FILTER_F_ALL_CTA_PROTO \
(CTA_FILTER_F_CTA_PROTO_SRC_PORT | \
CTA_FILTER_F_CTA_PROTO_DST_PORT | \
CTA_FILTER_F_CTA_PROTO_ICMP_TYPE | \
CTA_FILTER_F_CTA_PROTO_ICMP_CODE | \
CTA_FILTER_F_CTA_PROTO_ICMP_ID | \
CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE | \
CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE | \
CTA_FILTER_F_CTA_PROTO_ICMPV6_ID)
static int static int
ctnetlink_parse_tuple(const struct nlattr * const cda[], ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
struct nf_conntrack_tuple *tuple, u32 type, struct nf_conntrack_tuple *tuple, u32 type,
u_int8_t l3num, struct nf_conntrack_zone *zone) u_int8_t l3num, struct nf_conntrack_zone *zone,
u_int32_t flags)
{ {
struct nlattr *tb[CTA_TUPLE_MAX+1]; struct nlattr *tb[CTA_TUPLE_MAX+1];
int err; int err;
@ -1158,23 +1392,32 @@ ctnetlink_parse_tuple(const struct nlattr * const cda[],
if (err < 0) if (err < 0)
return err; return err;
if (!tb[CTA_TUPLE_IP])
return -EINVAL;
tuple->src.l3num = l3num; tuple->src.l3num = l3num;
err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple); if (flags & CTA_FILTER_FLAG(CTA_IP_DST) ||
flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
if (!tb[CTA_TUPLE_IP])
return -EINVAL;
err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple, flags);
if (err < 0) if (err < 0)
return err; return err;
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) {
if (!tb[CTA_TUPLE_PROTO]) if (!tb[CTA_TUPLE_PROTO])
return -EINVAL; return -EINVAL;
err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple); err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple, flags);
if (err < 0) if (err < 0)
return err; return err;
} else if (flags & CTA_FILTER_FLAG(ALL_CTA_PROTO)) {
/* Can't manage proto flags without a protonum */
return -EINVAL;
}
if (tb[CTA_TUPLE_ZONE]) { if ((flags & CTA_FILTER_FLAG(CTA_TUPLE_ZONE)) && tb[CTA_TUPLE_ZONE]) {
if (!zone) if (!zone)
return -EINVAL; return -EINVAL;
@ -1193,6 +1436,15 @@ ctnetlink_parse_tuple(const struct nlattr * const cda[],
return 0; return 0;
} }
static int
ctnetlink_parse_tuple(const struct nlattr * const cda[],
struct nf_conntrack_tuple *tuple, u32 type,
u_int8_t l3num, struct nf_conntrack_zone *zone)
{
return ctnetlink_parse_tuple_filter(cda, tuple, type, l3num, zone,
CTA_FILTER_FLAG(ALL));
}
static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = { static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
[CTA_HELP_NAME] = { .type = NLA_NUL_STRING, [CTA_HELP_NAME] = { .type = NLA_NUL_STRING,
.len = NF_CT_HELPER_NAME_LEN - 1 }, .len = NF_CT_HELPER_NAME_LEN - 1 },
@ -1240,6 +1492,7 @@ static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
.len = NF_CT_LABELS_MAX_SIZE }, .len = NF_CT_LABELS_MAX_SIZE },
[CTA_LABELS_MASK] = { .type = NLA_BINARY, [CTA_LABELS_MASK] = { .type = NLA_BINARY,
.len = NF_CT_LABELS_MAX_SIZE }, .len = NF_CT_LABELS_MAX_SIZE },
[CTA_FILTER] = { .type = NLA_NESTED },
}; };
static int ctnetlink_flush_iterate(struct nf_conn *ct, void *data) static int ctnetlink_flush_iterate(struct nf_conn *ct, void *data)
@ -1256,7 +1509,10 @@ static int ctnetlink_flush_conntrack(struct net *net,
{ {
struct ctnetlink_filter *filter = NULL; struct ctnetlink_filter *filter = NULL;
if (family || (cda[CTA_MARK] && cda[CTA_MARK_MASK])) { if (ctnetlink_needs_filter(family, cda)) {
if (cda[CTA_FILTER])
return -EOPNOTSUPP;
filter = ctnetlink_alloc_filter(cda, family); filter = ctnetlink_alloc_filter(cda, family);
if (IS_ERR(filter)) if (IS_ERR(filter))
return PTR_ERR(filter); return PTR_ERR(filter);
@ -1385,7 +1641,7 @@ static int ctnetlink_get_conntrack(struct net *net, struct sock *ctnl,
} }
err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq, err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq,
NFNL_MSG_TYPE(nlh->nlmsg_type), ct, true); NFNL_MSG_TYPE(nlh->nlmsg_type), ct, true, 0);
nf_ct_put(ct); nf_ct_put(ct);
if (err <= 0) if (err <= 0)
goto free; goto free;
@ -1458,7 +1714,7 @@ restart:
res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid, res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, cb->nlh->nlmsg_seq,
NFNL_MSG_TYPE(cb->nlh->nlmsg_type), NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
ct, dying ? true : false); ct, dying ? true : false, 0);
if (res < 0) { if (res < 0) {
if (!atomic_inc_not_zero(&ct->ct_general.use)) if (!atomic_inc_not_zero(&ct->ct_general.use))
continue; continue;

28
net/netfilter/nf_conntrack_proto_icmp.c
View File

@ -20,6 +20,8 @@
#include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_log.h> #include <net/netfilter/nf_log.h>
#include "nf_internals.h"
static const unsigned int nf_ct_icmp_timeout = 30*HZ; static const unsigned int nf_ct_icmp_timeout = 30*HZ;
bool icmp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff, bool icmp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
@ -271,20 +273,32 @@ static const struct nla_policy icmp_nla_policy[CTA_PROTO_MAX+1] = {
}; };
static int icmp_nlattr_to_tuple(struct nlattr *tb[], static int icmp_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *tuple) struct nf_conntrack_tuple *tuple,
u_int32_t flags)
{ {
if (!tb[CTA_PROTO_ICMP_TYPE] || if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_TYPE)) {
!tb[CTA_PROTO_ICMP_CODE] || if (!tb[CTA_PROTO_ICMP_TYPE])
!tb[CTA_PROTO_ICMP_ID])
return -EINVAL; return -EINVAL;
tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMP_TYPE]); tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMP_TYPE]);
tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMP_CODE]);
tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMP_ID]);
if (tuple->dst.u.icmp.type >= sizeof(invmap) || if (tuple->dst.u.icmp.type >= sizeof(invmap) ||
!invmap[tuple->dst.u.icmp.type]) !invmap[tuple->dst.u.icmp.type])
return -EINVAL; return -EINVAL;
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_CODE)) {
if (!tb[CTA_PROTO_ICMP_CODE])
return -EINVAL;
tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMP_CODE]);
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_ID)) {
if (!tb[CTA_PROTO_ICMP_ID])
return -EINVAL;
tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMP_ID]);
}
return 0; return 0;
} }

28
net/netfilter/nf_conntrack_proto_icmpv6.c
View File

@ -24,6 +24,8 @@
#include <net/netfilter/nf_conntrack_zones.h> #include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_log.h> #include <net/netfilter/nf_log.h>
#include "nf_internals.h"
static const unsigned int nf_ct_icmpv6_timeout = 30*HZ; static const unsigned int nf_ct_icmpv6_timeout = 30*HZ;
bool icmpv6_pkt_to_tuple(const struct sk_buff *skb, bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
@ -193,21 +195,33 @@ static const struct nla_policy icmpv6_nla_policy[CTA_PROTO_MAX+1] = {
}; };
static int icmpv6_nlattr_to_tuple(struct nlattr *tb[], static int icmpv6_nlattr_to_tuple(struct nlattr *tb[],
struct nf_conntrack_tuple *tuple) struct nf_conntrack_tuple *tuple,
u_int32_t flags)
{ {
if (!tb[CTA_PROTO_ICMPV6_TYPE] || if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_TYPE)) {
!tb[CTA_PROTO_ICMPV6_CODE] || if (!tb[CTA_PROTO_ICMPV6_TYPE])
!tb[CTA_PROTO_ICMPV6_ID])
return -EINVAL; return -EINVAL;
tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]); tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]);
tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]);
tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]);
if (tuple->dst.u.icmp.type < 128 || if (tuple->dst.u.icmp.type < 128 ||
tuple->dst.u.icmp.type - 128 >= sizeof(invmap) || tuple->dst.u.icmp.type - 128 >= sizeof(invmap) ||
!invmap[tuple->dst.u.icmp.type - 128]) !invmap[tuple->dst.u.icmp.type - 128])
return -EINVAL; return -EINVAL;
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_CODE)) {
if (!tb[CTA_PROTO_ICMPV6_CODE])
return -EINVAL;
tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]);
}
if (flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_ID)) {
if (!tb[CTA_PROTO_ICMPV6_ID])
return -EINVAL;
tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]);
}
return 0; return 0;
} }

17
net/netfilter/nf_internals.h
View File

@ -6,6 +6,23 @@
#include <linux/skbuff.h> #include <linux/skbuff.h>
#include <linux/netdevice.h> #include <linux/netdevice.h>
/* nf_conntrack_netlink.c: applied on tuple filters */
#define CTA_FILTER_F_CTA_IP_SRC (1 << 0)
#define CTA_FILTER_F_CTA_IP_DST (1 << 1)
#define CTA_FILTER_F_CTA_TUPLE_ZONE (1 << 2)
#define CTA_FILTER_F_CTA_PROTO_NUM (1 << 3)
#define CTA_FILTER_F_CTA_PROTO_SRC_PORT (1 << 4)
#define CTA_FILTER_F_CTA_PROTO_DST_PORT (1 << 5)
#define CTA_FILTER_F_CTA_PROTO_ICMP_TYPE (1 << 6)
#define CTA_FILTER_F_CTA_PROTO_ICMP_CODE (1 << 7)
#define CTA_FILTER_F_CTA_PROTO_ICMP_ID (1 << 8)
#define CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE (1 << 9)
#define CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE (1 << 10)
#define CTA_FILTER_F_CTA_PROTO_ICMPV6_ID (1 << 11)
#define CTA_FILTER_F_MAX (1 << 12)
#define CTA_FILTER_F_ALL (CTA_FILTER_F_MAX-1)
#define CTA_FILTER_FLAG(ctattr) CTA_FILTER_F_ ## ctattr
/* nf_queue.c */ /* nf_queue.c */
void nf_queue_nf_hook_drop(struct net *net); void nf_queue_nf_hook_drop(struct net *net);