Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

netfilter: implement xt_cgroup cgroup2 path match

Browse source 
This patch implements xt_cgroup path match which matches cgroup2
membership of the associated socket.  The match is recursive and
invertible.

For rationales on introducing another cgroup based match, please refer
to a preceding commit "sock, cgroup: add sock->sk_cgroup".

v3: Folded into xt_cgroup as a new revision interface as suggested by
    Pablo.

v2: Included linux/limits.h from xt_cgroup2.h for PATH_MAX.  Added
    explicit alignment to the priv field.  Both suggested by Jan.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Daniel Wagner <daniel.wagner@bmw-carit.de>
CC: Neil Horman <nhorman@tuxdriver.com>
Cc: Jan Engelhardt <jengelh@inai.de>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Tejun Heo 2015-12-07 17:38:55 -05:00 committed by Pablo Neira Ayuso
parent 4ec8ff0edc
commit c38c4597e4
2 changed files with 82 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

13
include/uapi/linux/netfilter/xt_cgroup.h
View file

@ -2,10 +2,23 @@
#define _UAPI_XT_CGROUP_H
#include <linux/types.h>
#include <linux/limits.h>
struct xt_cgroup_info_v0 {
__u32 id;
__u32 invert;
};
struct xt_cgroup_info_v1 {
__u8 has_path;
__u8 has_classid;
__u8 invert_path;
__u8 invert_classid;
char path[PATH_MAX];
__u32 classid;
/* kernel internal data */
void *priv __attribute__((aligned(8)));
};
#endif /* _UAPI_XT_CGROUP_H */

69
net/netfilter/xt_cgroup.c
View file

@ -34,6 +34,37 @@ static int cgroup_mt_check_v0(const struct xt_mtchk_param *par)
return 0;
}
static int cgroup_mt_check_v1(const struct xt_mtchk_param *par)
{
struct xt_cgroup_info_v1 *info = par->matchinfo;
struct cgroup *cgrp;
if ((info->invert_path & ~1) || (info->invert_classid & ~1))
return -EINVAL;
if (!info->has_path && !info->has_classid) {
pr_info("xt_cgroup: no path or classid specified\n");
return -EINVAL;
}
if (info->has_path && info->has_classid) {
pr_info("xt_cgroup: both path and classid specified\n");
return -EINVAL;
}
if (info->has_path) {
cgrp = cgroup_get_from_path(info->path);
if (IS_ERR(cgrp)) {
pr_info("xt_cgroup: invalid path, errno=%ld\n",
PTR_ERR(cgrp));
return -EINVAL;
}
info->priv = cgrp;
}
return 0;
}
static bool
cgroup_mt_v0(const struct sk_buff *skb, struct xt_action_param *par)
{
@ -46,6 +77,31 @@ cgroup_mt_v0(const struct sk_buff *skb, struct xt_action_param *par)
info->invert;
}
static bool cgroup_mt_v1(const struct sk_buff *skb, struct xt_action_param *par)
{
const struct xt_cgroup_info_v1 *info = par->matchinfo;
struct sock_cgroup_data *skcd = &skb->sk->sk_cgrp_data;
struct cgroup *ancestor = info->priv;
if (!skb->sk || !sk_fullsock(skb->sk))
return false;
if (ancestor)
return cgroup_is_descendant(sock_cgroup_ptr(skcd), ancestor) ^
info->invert_path;
else
return (info->classid == sock_cgroup_classid(skcd)) ^
info->invert_classid;
}
static void cgroup_mt_destroy_v1(const struct xt_mtdtor_param *par)
{
struct xt_cgroup_info_v1 *info = par->matchinfo;
if (info->priv)
cgroup_put(info->priv);
}
static struct xt_match cgroup_mt_reg[] __read_mostly = {
{
.name = "cgroup",
@ -59,6 +115,19 @@ static struct xt_match cgroup_mt_reg[] __read_mostly = {
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_IN),
},
{
.name = "cgroup",
.revision = 1,
.family = NFPROTO_UNSPEC,
.checkentry = cgroup_mt_check_v1,
.match = cgroup_mt_v1,
.matchsize = sizeof(struct xt_cgroup_info_v1),
.destroy = cgroup_mt_destroy_v1,
.me = THIS_MODULE,
.hooks = (1 << NF_INET_LOCAL_OUT) |
(1 << NF_INET_POST_ROUTING) |
(1 << NF_INET_LOCAL_IN),
},
};
static int __init cgroup_mt_init(void)