From 42f39036cda808d3de243192a2cf5125f12f3047 Mon Sep 17 00:00:00 2001 From: Victor Nogueira Date: Tue, 19 Dec 2023 15:16:23 -0300 Subject: net/sched: act_mirred: Allow mirred to block So far the mirred action has dealt with syntax that handles mirror/redirection for netdev. A matching packet is redirected or mirrored to a target netdev. In this patch we enable mirred to mirror to a tc block as well. IOW, the new syntax looks as follows: ... mirred [index INDEX] < | > > Examples of mirroring or redirecting to a tc block: $ tc filter add block 22 protocol ip pref 25 \ flower dst_ip 192.168.0.0/16 action mirred egress mirror blockid 22 $ tc filter add block 22 protocol ip pref 25 \ flower dst_ip 10.10.10.10/32 action mirred egress redirect blockid 22 Co-developed-by: Jamal Hadi Salim Signed-off-by: Jamal Hadi Salim Co-developed-by: Pedro Tammela Signed-off-by: Pedro Tammela Signed-off-by: Victor Nogueira Signed-off-by: David S. Miller --- include/net/tc_act/tc_mirred.h | 1 + include/uapi/linux/tc_act/tc_mirred.h | 1 + net/sched/act_mirred.c | 119 +++++++++++++++++++++++++++++++++- 3 files changed, 119 insertions(+), 2 deletions(-) diff --git a/include/net/tc_act/tc_mirred.h b/include/net/tc_act/tc_mirred.h index 32ce8ea36950..75722d967bf2 100644 --- a/include/net/tc_act/tc_mirred.h +++ b/include/net/tc_act/tc_mirred.h @@ -8,6 +8,7 @@ struct tcf_mirred { struct tc_action common; int tcfm_eaction; + u32 tcfm_blockid; bool tcfm_mac_header_xmit; struct net_device __rcu *tcfm_dev; netdevice_tracker tcfm_dev_tracker; diff --git a/include/uapi/linux/tc_act/tc_mirred.h b/include/uapi/linux/tc_act/tc_mirred.h index 2500a0005d05..c61e76f3c23b 100644 --- a/include/uapi/linux/tc_act/tc_mirred.h +++ b/include/uapi/linux/tc_act/tc_mirred.h @@ -21,6 +21,7 @@ enum { TCA_MIRRED_TM, TCA_MIRRED_PARMS, TCA_MIRRED_PAD, + TCA_MIRRED_BLOCKID, __TCA_MIRRED_MAX }; #define TCA_MIRRED_MAX (__TCA_MIRRED_MAX - 1) diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index a1be8f3c4a8e..d1f9794ca9b7 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -85,6 +85,7 @@ static void tcf_mirred_release(struct tc_action *a) static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, + [TCA_MIRRED_BLOCKID] = NLA_POLICY_MIN(NLA_U32, 1), }; static struct tc_action_ops act_mirred_ops; @@ -136,6 +137,17 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, if (exists && bind) return 0; + if (tb[TCA_MIRRED_BLOCKID] && parm->ifindex) { + NL_SET_ERR_MSG_MOD(extack, + "Cannot specify Block ID and dev simultaneously"); + if (exists) + tcf_idr_release(*a, bind); + else + tcf_idr_cleanup(tn, index); + + return -EINVAL; + } + switch (parm->eaction) { case TCA_EGRESS_MIRROR: case TCA_EGRESS_REDIR: @@ -152,9 +164,10 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, } if (!exists) { - if (!parm->ifindex) { + if (!parm->ifindex && !tb[TCA_MIRRED_BLOCKID]) { tcf_idr_cleanup(tn, index); - NL_SET_ERR_MSG_MOD(extack, "Specified device does not exist"); + NL_SET_ERR_MSG_MOD(extack, + "Must specify device or block"); return -EINVAL; } ret = tcf_idr_create_from_flags(tn, index, est, a, @@ -192,6 +205,11 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, tcf_mirred_replace_dev(m, ndev); netdev_tracker_alloc(ndev, &m->tcfm_dev_tracker, GFP_ATOMIC); m->tcfm_mac_header_xmit = mac_header_xmit; + m->tcfm_blockid = 0; + } else if (tb[TCA_MIRRED_BLOCKID]) { + tcf_mirred_replace_dev(m, NULL); + m->tcfm_mac_header_xmit = false; + m->tcfm_blockid = nla_get_u32(tb[TCA_MIRRED_BLOCKID]); } goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); m->tcfm_eaction = parm->eaction; @@ -316,6 +334,89 @@ out: return retval; } +static int tcf_blockcast_redir(struct sk_buff *skb, struct tcf_mirred *m, + struct tcf_block *block, int m_eaction, + const u32 exception_ifindex, int retval) +{ + struct net_device *dev_prev = NULL; + struct net_device *dev = NULL; + unsigned long index; + int mirred_eaction; + + mirred_eaction = tcf_mirred_act_wants_ingress(m_eaction) ? + TCA_INGRESS_MIRROR : TCA_EGRESS_MIRROR; + + xa_for_each(&block->ports, index, dev) { + if (index == exception_ifindex) + continue; + + if (!dev_prev) + goto assign_prev; + + tcf_mirred_to_dev(skb, m, dev_prev, + dev_is_mac_header_xmit(dev), + mirred_eaction, retval); +assign_prev: + dev_prev = dev; + } + + if (dev_prev) + return tcf_mirred_to_dev(skb, m, dev_prev, + dev_is_mac_header_xmit(dev_prev), + m_eaction, retval); + + return retval; +} + +static int tcf_blockcast_mirror(struct sk_buff *skb, struct tcf_mirred *m, + struct tcf_block *block, int m_eaction, + const u32 exception_ifindex, int retval) +{ + struct net_device *dev = NULL; + unsigned long index; + + xa_for_each(&block->ports, index, dev) { + if (index == exception_ifindex) + continue; + + tcf_mirred_to_dev(skb, m, dev, + dev_is_mac_header_xmit(dev), + m_eaction, retval); + } + + return retval; +} + +static int tcf_blockcast(struct sk_buff *skb, struct tcf_mirred *m, + const u32 blockid, struct tcf_result *res, + int retval) +{ + const u32 exception_ifindex = skb->dev->ifindex; + struct tcf_block *block; + bool is_redirect; + int m_eaction; + + m_eaction = READ_ONCE(m->tcfm_eaction); + is_redirect = tcf_mirred_is_act_redirect(m_eaction); + + /* we are already under rcu protection, so can call block lookup + * directly. + */ + block = tcf_block_lookup(dev_net(skb->dev), blockid); + if (!block || xa_empty(&block->ports)) { + tcf_action_inc_overlimit_qstats(&m->common); + return retval; + } + + if (is_redirect) + return tcf_blockcast_redir(skb, m, block, m_eaction, + exception_ifindex, retval); + + /* If it's not redirect, it is mirror */ + return tcf_blockcast_mirror(skb, m, block, m_eaction, exception_ifindex, + retval); +} + TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a, struct tcf_result *res) @@ -326,6 +427,7 @@ TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, bool m_mac_header_xmit; struct net_device *dev; int m_eaction; + u32 blockid; nest_level = __this_cpu_inc_return(mirred_nest_level); if (unlikely(nest_level > MIRRED_NEST_LIMIT)) { @@ -338,6 +440,12 @@ TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, tcf_lastuse_update(&m->tcf_tm); tcf_action_update_bstats(&m->common, skb); + blockid = READ_ONCE(m->tcfm_blockid); + if (blockid) { + retval = tcf_blockcast(skb, m, blockid, res, retval); + goto dec_nest_level; + } + dev = rcu_dereference_bh(m->tcfm_dev); if (unlikely(!dev)) { pr_notice_once("tc mirred: target device is gone\n"); @@ -379,6 +487,7 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, }; struct net_device *dev; struct tcf_t t; + u32 blockid; spin_lock_bh(&m->tcf_lock); opt.action = m->tcf_action; @@ -390,6 +499,10 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) goto nla_put_failure; + blockid = m->tcfm_blockid; + if (blockid && nla_put_u32(skb, TCA_MIRRED_BLOCKID, blockid)) + goto nla_put_failure; + tcf_tm_dump(&t, &m->tcf_tm); if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD)) goto nla_put_failure; @@ -420,6 +533,8 @@ static int mirred_device_event(struct notifier_block *unused, * net_device are already rcu protected. */ RCU_INIT_POINTER(m->tcfm_dev, NULL); + } else if (m->tcfm_blockid) { + m->tcfm_blockid = 0; } spin_unlock_bh(&m->tcf_lock); } -- cgit