| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1484430764-30788-1-git-send-email-jhs@emojatatu.com>
Date: Sat, 14 Jan 2017 16:52:44 -0500
From: Jamal Hadi Salim <jhs@...atatu.com>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org, jiri@...lanox.com, paulb@...lanox.com,
john.fastabend@...il.com, simon.horman@...ronome.com,
mrv@...atatu.com, hadarh@...lanox.com, ogerlitz@...lanox.com,
roid@...lanox.com, xiyou.wangcong@...il.com, daniel@...earbox.net,
Jamal Hadi Salim <jhs@...atatu.com>
Subject: [PATCH net-next 1/1] net sched actions: Add support for user cookies
From: Jamal Hadi Salim <jhs@...atatu.com>
Introduce optional 128-bit action cookie.
Like all other cookie schemes in the networking world (eg in protocols
like http or existing kernel fib protocol field, etc) the idea is to save
user state that when retrieved serves as a correlator. The kernel
_should not_ intepret it. The user can store whatever they wish in the
128 bits.
Sample exercise(using two 64bit values to represent the 128 bits):
.. create an accept action with cookie a1b2c3d4
sudo $TC actions add action ok index 1 cookie a1b2c3d4
.. dump all gact actions..
sudo $TC -s actions ls action gact
action order 0: gact action pass
random type none pass val 0
index 1 ref 1 bind 0 installed 5 sec used 5 sec
Action statistics:
Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
cookie a1b2c3d4
.. bind the accept action to a filter..
sudo $TC filter add dev lo parent ffff: protocol ip prio 1 \
u32 match ip dst 127.0.0.1/32 flowid 1:1 action gact index 1
... send some traffic..
$ ping 127.0.0.1 -c 3
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.020 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.027 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.038 ms
--- 127.0.0.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2109ms
rtt min/avg/max/mdev = 0.020/0.028/0.038/0.008 ms 1
... show some stats
$ sudo $TC -s actions get action gact index 1
action order 1: gact action pass
random type none pass val 0
index 1 ref 2 bind 1 installed 204 sec used 5 sec
Action statistics:
Sent 12168 bytes 164 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
cookie a1b2c3d4
.. try longer cookie...
$ sudo $TC actions replace action ok index 1 cookie 1234567890abcdef
.. dump..
$ sudo $TC -s actions ls action gact
action order 1: gact action pass
random type none pass val 0
index 1 ref 2 bind 1 installed 204 sec used 5 sec
Action statistics:
Sent 12168 bytes 164 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
cookie 1234567890abcdef
Signed-off-by: Jamal Hadi Salim <jhs@...atatu.com>
---
include/net/act_api.h | 1 +
include/uapi/linux/pkt_cls.h | 11 +++++++++++
net/sched/act_api.c | 28 ++++++++++++++++++++++++++--
3 files changed, 38 insertions(+), 2 deletions(-)
diff --git a/include/net/act_api.h b/include/net/act_api.h
index 1d71644..0692458 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -41,6 +41,7 @@ struct tc_action {
struct rcu_head tcfa_rcu;
struct gnet_stats_basic_cpu __percpu *cpu_bstats;
struct gnet_stats_queue __percpu *cpu_qstats;
+ struct tc_cookie *act_ck;
};
#define tcf_head common.tcfa_head
#define tcf_index common.tcfa_index
diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
index 1e5e1dd..063bc89 100644
--- a/include/uapi/linux/pkt_cls.h
+++ b/include/uapi/linux/pkt_cls.h
@@ -4,6 +4,16 @@
#include <linux/types.h>
#include <linux/pkt_sched.h>
+#define MAX_TC_COOKIE_SZ 16
+
+/* This structure holds cookie structure that is passed from user
+ * to the kernel for actions and classifiers
+ */
+struct tc_cookie {
+ unsigned char ck[MAX_TC_COOKIE_SZ];
+ unsigned char ck_len;
+};
+
/* Action attributes */
enum {
TCA_ACT_UNSPEC,
@@ -12,6 +22,7 @@ enum {
TCA_ACT_INDEX,
TCA_ACT_STATS,
TCA_ACT_PAD,
+ TCA_ACT_COOKIE,
__TCA_ACT_MAX
};
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index f04715a..b82908a 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -33,6 +33,7 @@ static void free_tcf(struct rcu_head *head)
free_percpu(p->cpu_bstats);
free_percpu(p->cpu_qstats);
+ kfree(p->act_ck);
kfree(p);
}
@@ -464,8 +465,8 @@ int tcf_action_destroy(struct list_head *actions, int bind)
return a->ops->dump(skb, a, bind, ref);
}
-int
-tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
+int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind,
+ int ref)
{
int err = -EINVAL;
unsigned char *b = skb_tail_pointer(skb);
@@ -475,6 +476,12 @@ int tcf_action_destroy(struct list_head *actions, int bind)
goto nla_put_failure;
if (tcf_action_copy_stats(skb, a, 0))
goto nla_put_failure;
+ if (a->act_ck) {
+ if (nla_put(skb, TCA_ACT_COOKIE, a->act_ck->ck_len,
+ a->act_ck))
+ goto nla_put_failure;
+ }
+
nest = nla_nest_start(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
@@ -575,6 +582,23 @@ struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla,
if (err < 0)
goto err_mod;
+ if (tb[TCA_ACT_COOKIE]) {
+ if (nla_len(tb[TCA_ACT_COOKIE]) > MAX_TC_COOKIE_SZ) {
+ err = -EINVAL;
+ goto err_mod;
+ }
+
+ a->act_ck = kzalloc(sizeof(*a->act_ck), GFP_KERNEL);
+ if (unlikely(!a->act_ck)) {
+ err = -ENOMEM;
+ goto err_mod;
+ }
+
+ memcpy((void *)a->act_ck->ck, nla_data(tb[TCA_ACT_COOKIE]),
+ nla_len(tb[TCA_ACT_COOKIE]));
+ a->act_ck->ck_len = nla_len(tb[TCA_ACT_COOKIE]);
+ }
+
/* module count goes up only when brand new policy is created
* if it exists and is only bound to in a_o->init() then
* ACT_P_CREATED is not returned (a zero is).
--
1.9.1
Powered by blists - more mailing lists