| Message ID | 1485259361-16860-1-git-send-email-jhs@emojatatu.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
Tue, Jan 24, 2017 at 01:02:41PM CET, jhs@mojatatu.com wrote: >From: Jamal Hadi Salim <jhs@mojatatu.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(showing variable length use of cookie) > >.. 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@mojatatu.com> >--- >Changes in v7: > -put guard around freeing cookie (caught by Simon) > -separate out the creation of the cookie (suggested by Simon) > >Changes in v6: > - fix mem leak caught by Florian > >Changes in V5: > - kill the stylistic changes > - Adopt a new structure with length-valuepointer representation > - rename some things > >Changes in v4: > - move stylistic changes out into a separate patch > (and add more stylistic changes) > >Changes in v3: > - use TC_ prefix for the max size > - move the cookie struct so visible only to kernel > - remove unneeded void * cast > >Changes in V2: > -move from a union to a length-value representation > > include/net/act_api.h | 1 + > include/net/pkt_cls.h | 8 ++++++++ > include/uapi/linux/pkt_cls.h | 3 +++ > net/sched/act_api.c | 45 ++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 57 insertions(+) > >diff --git a/include/net/act_api.h b/include/net/act_api.h >index 1d71644..cfa2ae3 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_cookie; > }; > #define tcf_head common.tcfa_head > #define tcf_index common.tcfa_index >diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h >index f0a0514..b43077e 100644 >--- a/include/net/pkt_cls.h >+++ b/include/net/pkt_cls.h >@@ -515,4 +515,12 @@ struct tc_cls_bpf_offload { > u32 gen_flags; > }; > >+ >+/* This structure holds cookie structure that is passed from user >+ * to the kernel for actions and classifiers >+ */ >+struct tc_cookie { >+ u8 *data; >+ u32 len; >+}; > #endif >diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h >index fd373eb..345551e 100644 >--- a/include/uapi/linux/pkt_cls.h >+++ b/include/uapi/linux/pkt_cls.h >@@ -4,6 +4,8 @@ > #include <linux/types.h> > #include <linux/pkt_sched.h> > >+#define TC_COOKIE_MAX_SIZE 16 >+ > /* Action attributes */ > enum { > TCA_ACT_UNSPEC, >@@ -12,6 +14,7 @@ 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 cd08df9..3c5e29b 100644 >--- a/net/sched/act_api.c >+++ b/net/sched/act_api.c >@@ -24,6 +24,7 @@ > #include <net/net_namespace.h> > #include <net/sock.h> > #include <net/sch_generic.h> >+#include <net/pkt_cls.h> > #include <net/act_api.h> > #include <net/netlink.h> > >@@ -33,6 +34,12 @@ static void free_tcf(struct rcu_head *head) > > free_percpu(p->cpu_bstats); > free_percpu(p->cpu_qstats); >+ >+ if (p->act_cookie) { >+ kfree(p->act_cookie->data); >+ kfree(p->act_cookie); >+ } >+ > kfree(p); > } > >@@ -475,6 +482,12 @@ 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_cookie) { >+ if (nla_put(skb, TCA_ACT_COOKIE, a->act_cookie->len, >+ a->act_cookie->data)) >+ goto nla_put_failure; >+ } >+ > nest = nla_nest_start(skb, TCA_OPTIONS); > if (nest == NULL) > goto nla_put_failure; >@@ -516,6 +529,22 @@ int tcf_action_dump(struct sk_buff *skb, struct list_head *actions, > return err; > } > >+int nla_memdup_cookie(struct tc_action *a, struct nlattr **tb) >+{ >+ a->act_cookie = kzalloc(sizeof(*a->act_cookie), GFP_KERNEL); >+ if (!a->act_cookie) >+ return -ENOMEM; >+ >+ a->act_cookie->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL); you can do just: size_t len = nla_len(tb[TCA_ACT_COOKIE]; a->act_cookie = kzalloc(sizeof(*a->act_cookie) + len, GFP_KERNEL); if (!a->act_cookie) return -ENOMEM; memcpy(a->act_cookie->data, nla_data(tb[TCA_ACT_COOKIE], len)); a->act_cookie->len = len; return 0; Really see no need to alloc 2 chunks instead of one. But as you like. >+ if (!a->act_cookie->data) { >+ kfree(a->act_cookie); >+ return -ENOMEM; >+ } >+ a->act_cookie->len = nla_len(tb[TCA_ACT_COOKIE]); >+ >+ return 0; >+} >+ > struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla, > struct nlattr *est, char *name, int ovr, > int bind) >@@ -575,6 +604,22 @@ struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla, > if (err < 0) > goto err_mod; > >+ if (tb[TCA_ACT_COOKIE]) { >+ int cklen = nla_len(tb[TCA_ACT_COOKIE]); >+ >+ if (cklen > TC_COOKIE_MAX_SIZE) { >+ err = -EINVAL; >+ tcf_hash_release(a, bind); >+ goto err_mod; >+ } >+ >+ err = nla_memdup_cookie(a, tb); >+ if (err < 0) { You can do just "if (err)", but anyway: Reviewed-by: Jiri Pirko <jiri@mellanox.com> >+ tcf_hash_release(a, bind); >+ goto err_mod; >+ } >+ } >+ > /* 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 >
From: Jamal Hadi Salim <jhs@mojatatu.com> Date: Tue, 24 Jan 2017 07:02:41 -0500 > Introduce optional 128-bit action cookie. Applied, but like Jiri I think you can use one buffer instead of two to store the user's cookie data. Thanks.
diff --git a/include/net/act_api.h b/include/net/act_api.h index 1d71644..cfa2ae3 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_cookie; }; #define tcf_head common.tcfa_head #define tcf_index common.tcfa_index diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h index f0a0514..b43077e 100644 --- a/include/net/pkt_cls.h +++ b/include/net/pkt_cls.h @@ -515,4 +515,12 @@ struct tc_cls_bpf_offload { u32 gen_flags; }; + +/* This structure holds cookie structure that is passed from user + * to the kernel for actions and classifiers + */ +struct tc_cookie { + u8 *data; + u32 len; +}; #endif diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h index fd373eb..345551e 100644 --- a/include/uapi/linux/pkt_cls.h +++ b/include/uapi/linux/pkt_cls.h @@ -4,6 +4,8 @@ #include <linux/types.h> #include <linux/pkt_sched.h> +#define TC_COOKIE_MAX_SIZE 16 + /* Action attributes */ enum { TCA_ACT_UNSPEC, @@ -12,6 +14,7 @@ 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 cd08df9..3c5e29b 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -24,6 +24,7 @@ #include <net/net_namespace.h> #include <net/sock.h> #include <net/sch_generic.h> +#include <net/pkt_cls.h> #include <net/act_api.h> #include <net/netlink.h> @@ -33,6 +34,12 @@ static void free_tcf(struct rcu_head *head) free_percpu(p->cpu_bstats); free_percpu(p->cpu_qstats); + + if (p->act_cookie) { + kfree(p->act_cookie->data); + kfree(p->act_cookie); + } + kfree(p); } @@ -475,6 +482,12 @@ 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_cookie) { + if (nla_put(skb, TCA_ACT_COOKIE, a->act_cookie->len, + a->act_cookie->data)) + goto nla_put_failure; + } + nest = nla_nest_start(skb, TCA_OPTIONS); if (nest == NULL) goto nla_put_failure; @@ -516,6 +529,22 @@ int tcf_action_dump(struct sk_buff *skb, struct list_head *actions, return err; } +int nla_memdup_cookie(struct tc_action *a, struct nlattr **tb) +{ + a->act_cookie = kzalloc(sizeof(*a->act_cookie), GFP_KERNEL); + if (!a->act_cookie) + return -ENOMEM; + + a->act_cookie->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL); + if (!a->act_cookie->data) { + kfree(a->act_cookie); + return -ENOMEM; + } + a->act_cookie->len = nla_len(tb[TCA_ACT_COOKIE]); + + return 0; +} + struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind) @@ -575,6 +604,22 @@ struct tc_action *tcf_action_init_1(struct net *net, struct nlattr *nla, if (err < 0) goto err_mod; + if (tb[TCA_ACT_COOKIE]) { + int cklen = nla_len(tb[TCA_ACT_COOKIE]); + + if (cklen > TC_COOKIE_MAX_SIZE) { + err = -EINVAL; + tcf_hash_release(a, bind); + goto err_mod; + } + + err = nla_memdup_cookie(a, tb); + if (err < 0) { + tcf_hash_release(a, bind); + goto err_mod; + } + } + /* 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).