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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /net/sched/act_ipt.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/sched/act_ipt.c')
-rw-r--r-- | net/sched/act_ipt.c | 464 |
1 files changed, 464 insertions, 0 deletions
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c new file mode 100644 index 0000000000..598d6e2991 --- /dev/null +++ b/net/sched/act_ipt.c @@ -0,0 +1,464 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * net/sched/act_ipt.c iptables target interface + * + *TODO: Add other tables. For now we only support the ipv4 table targets + * + * Copyright: Jamal Hadi Salim (2002-13) + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/skbuff.h> +#include <linux/rtnetlink.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <net/netlink.h> +#include <net/pkt_sched.h> +#include <linux/tc_act/tc_ipt.h> +#include <net/tc_act/tc_ipt.h> +#include <net/tc_wrapper.h> +#include <net/ip.h> + +#include <linux/netfilter_ipv4/ip_tables.h> + + +static struct tc_action_ops act_ipt_ops; +static struct tc_action_ops act_xt_ops; + +static int ipt_init_target(struct net *net, struct xt_entry_target *t, + char *table, unsigned int hook) +{ + struct xt_tgchk_param par; + struct xt_target *target; + struct ipt_entry e = {}; + int ret = 0; + + target = xt_request_find_target(AF_INET, t->u.user.name, + t->u.user.revision); + if (IS_ERR(target)) + return PTR_ERR(target); + + t->u.kernel.target = target; + memset(&par, 0, sizeof(par)); + par.net = net; + par.table = table; + par.entryinfo = &e; + par.target = target; + par.targinfo = t->data; + par.hook_mask = 1 << hook; + par.family = NFPROTO_IPV4; + + ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false); + if (ret < 0) { + module_put(t->u.kernel.target->me); + return ret; + } + return 0; +} + +static void ipt_destroy_target(struct xt_entry_target *t, struct net *net) +{ + struct xt_tgdtor_param par = { + .target = t->u.kernel.target, + .targinfo = t->data, + .family = NFPROTO_IPV4, + .net = net, + }; + if (par.target->destroy != NULL) + par.target->destroy(&par); + module_put(par.target->me); +} + +static void tcf_ipt_release(struct tc_action *a) +{ + struct tcf_ipt *ipt = to_ipt(a); + + if (ipt->tcfi_t) { + ipt_destroy_target(ipt->tcfi_t, a->idrinfo->net); + kfree(ipt->tcfi_t); + } + kfree(ipt->tcfi_tname); +} + +static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = { + [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ }, + [TCA_IPT_HOOK] = NLA_POLICY_RANGE(NLA_U32, NF_INET_PRE_ROUTING, + NF_INET_NUMHOOKS), + [TCA_IPT_INDEX] = { .type = NLA_U32 }, + [TCA_IPT_TARG] = { .len = sizeof(struct xt_entry_target) }, +}; + +static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + const struct tc_action_ops *ops, + struct tcf_proto *tp, u32 flags) +{ + struct tc_action_net *tn = net_generic(net, id); + bool bind = flags & TCA_ACT_FLAGS_BIND; + struct nlattr *tb[TCA_IPT_MAX + 1]; + struct tcf_ipt *ipt; + struct xt_entry_target *td, *t; + char *tname; + bool exists = false; + int ret = 0, err; + u32 hook = 0; + u32 index = 0; + + if (nla == NULL) + return -EINVAL; + + err = nla_parse_nested_deprecated(tb, TCA_IPT_MAX, nla, ipt_policy, + NULL); + if (err < 0) + return err; + + if (tb[TCA_IPT_INDEX] != NULL) + index = nla_get_u32(tb[TCA_IPT_INDEX]); + + err = tcf_idr_check_alloc(tn, &index, a, bind); + if (err < 0) + return err; + exists = err; + if (exists && bind) + return 0; + + if (tb[TCA_IPT_HOOK] == NULL || tb[TCA_IPT_TARG] == NULL) { + if (exists) + tcf_idr_release(*a, bind); + else + tcf_idr_cleanup(tn, index); + return -EINVAL; + } + + td = (struct xt_entry_target *)nla_data(tb[TCA_IPT_TARG]); + if (nla_len(tb[TCA_IPT_TARG]) != td->u.target_size) { + if (exists) + tcf_idr_release(*a, bind); + else + tcf_idr_cleanup(tn, index); + return -EINVAL; + } + + if (!exists) { + ret = tcf_idr_create(tn, index, est, a, ops, bind, + false, flags); + if (ret) { + tcf_idr_cleanup(tn, index); + return ret; + } + ret = ACT_P_CREATED; + } else { + if (bind)/* dont override defaults */ + return 0; + + if (!(flags & TCA_ACT_FLAGS_REPLACE)) { + tcf_idr_release(*a, bind); + return -EEXIST; + } + } + + err = -EINVAL; + hook = nla_get_u32(tb[TCA_IPT_HOOK]); + switch (hook) { + case NF_INET_PRE_ROUTING: + break; + case NF_INET_POST_ROUTING: + break; + default: + goto err1; + } + + if (tb[TCA_IPT_TABLE]) { + /* mangle only for now */ + if (nla_strcmp(tb[TCA_IPT_TABLE], "mangle")) + goto err1; + } + + tname = kstrdup("mangle", GFP_KERNEL); + if (unlikely(!tname)) + goto err1; + + t = kmemdup(td, td->u.target_size, GFP_KERNEL); + if (unlikely(!t)) + goto err2; + + err = ipt_init_target(net, t, tname, hook); + if (err < 0) + goto err3; + + ipt = to_ipt(*a); + + spin_lock_bh(&ipt->tcf_lock); + if (ret != ACT_P_CREATED) { + ipt_destroy_target(ipt->tcfi_t, net); + kfree(ipt->tcfi_tname); + kfree(ipt->tcfi_t); + } + ipt->tcfi_tname = tname; + ipt->tcfi_t = t; + ipt->tcfi_hook = hook; + spin_unlock_bh(&ipt->tcf_lock); + return ret; + +err3: + kfree(t); +err2: + kfree(tname); +err1: + tcf_idr_release(*a, bind); + return err; +} + +static int tcf_ipt_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + struct tcf_proto *tp, + u32 flags, struct netlink_ext_ack *extack) +{ + return __tcf_ipt_init(net, act_ipt_ops.net_id, nla, est, + a, &act_ipt_ops, tp, flags); +} + +static int tcf_xt_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + struct tcf_proto *tp, + u32 flags, struct netlink_ext_ack *extack) +{ + return __tcf_ipt_init(net, act_xt_ops.net_id, nla, est, + a, &act_xt_ops, tp, flags); +} + +static bool tcf_ipt_act_check(struct sk_buff *skb) +{ + const struct iphdr *iph; + unsigned int nhoff, len; + + if (!pskb_may_pull(skb, sizeof(struct iphdr))) + return false; + + nhoff = skb_network_offset(skb); + iph = ip_hdr(skb); + if (iph->ihl < 5 || iph->version != 4) + return false; + + len = skb_ip_totlen(skb); + if (skb->len < nhoff + len || len < (iph->ihl * 4u)) + return false; + + return pskb_may_pull(skb, iph->ihl * 4u); +} + +TC_INDIRECT_SCOPE int tcf_ipt_act(struct sk_buff *skb, + const struct tc_action *a, + struct tcf_result *res) +{ + char saved_cb[sizeof_field(struct sk_buff, cb)]; + int ret = 0, result = 0; + struct tcf_ipt *ipt = to_ipt(a); + struct xt_action_param par; + struct nf_hook_state state = { + .net = dev_net(skb->dev), + .in = skb->dev, + .hook = ipt->tcfi_hook, + .pf = NFPROTO_IPV4, + }; + + if (skb_protocol(skb, false) != htons(ETH_P_IP)) + return TC_ACT_UNSPEC; + + if (skb_unclone(skb, GFP_ATOMIC)) + return TC_ACT_UNSPEC; + + if (!tcf_ipt_act_check(skb)) + return TC_ACT_UNSPEC; + + if (state.hook == NF_INET_POST_ROUTING) { + if (!skb_dst(skb)) + return TC_ACT_UNSPEC; + + state.out = skb->dev; + } + + memcpy(saved_cb, skb->cb, sizeof(saved_cb)); + + spin_lock(&ipt->tcf_lock); + + tcf_lastuse_update(&ipt->tcf_tm); + bstats_update(&ipt->tcf_bstats, skb); + + /* yes, we have to worry about both in and out dev + * worry later - danger - this API seems to have changed + * from earlier kernels + */ + par.state = &state; + par.target = ipt->tcfi_t->u.kernel.target; + par.targinfo = ipt->tcfi_t->data; + + memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); + + ret = par.target->target(skb, &par); + + switch (ret) { + case NF_ACCEPT: + result = TC_ACT_OK; + break; + case NF_DROP: + result = TC_ACT_SHOT; + ipt->tcf_qstats.drops++; + break; + case XT_CONTINUE: + result = TC_ACT_PIPE; + break; + default: + net_notice_ratelimited("tc filter: Bogus netfilter code %d assume ACCEPT\n", + ret); + result = TC_ACT_OK; + break; + } + spin_unlock(&ipt->tcf_lock); + + memcpy(skb->cb, saved_cb, sizeof(skb->cb)); + + return result; + +} + +static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, + int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_ipt *ipt = to_ipt(a); + struct xt_entry_target *t; + struct tcf_t tm; + struct tc_cnt c; + + /* for simple targets kernel size == user size + * user name = target name + * for foolproof you need to not assume this + */ + + spin_lock_bh(&ipt->tcf_lock); + t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC); + if (unlikely(!t)) + goto nla_put_failure; + + c.bindcnt = atomic_read(&ipt->tcf_bindcnt) - bind; + c.refcnt = refcount_read(&ipt->tcf_refcnt) - ref; + strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name); + + if (nla_put(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t) || + nla_put_u32(skb, TCA_IPT_INDEX, ipt->tcf_index) || + nla_put_u32(skb, TCA_IPT_HOOK, ipt->tcfi_hook) || + nla_put(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c) || + nla_put_string(skb, TCA_IPT_TABLE, ipt->tcfi_tname)) + goto nla_put_failure; + + tcf_tm_dump(&tm, &ipt->tcf_tm); + if (nla_put_64bit(skb, TCA_IPT_TM, sizeof(tm), &tm, TCA_IPT_PAD)) + goto nla_put_failure; + + spin_unlock_bh(&ipt->tcf_lock); + kfree(t); + return skb->len; + +nla_put_failure: + spin_unlock_bh(&ipt->tcf_lock); + nlmsg_trim(skb, b); + kfree(t); + return -1; +} + +static struct tc_action_ops act_ipt_ops = { + .kind = "ipt", + .id = TCA_ID_IPT, + .owner = THIS_MODULE, + .act = tcf_ipt_act, + .dump = tcf_ipt_dump, + .cleanup = tcf_ipt_release, + .init = tcf_ipt_init, + .size = sizeof(struct tcf_ipt), +}; + +static __net_init int ipt_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, act_ipt_ops.net_id); + + return tc_action_net_init(net, tn, &act_ipt_ops); +} + +static void __net_exit ipt_exit_net(struct list_head *net_list) +{ + tc_action_net_exit(net_list, act_ipt_ops.net_id); +} + +static struct pernet_operations ipt_net_ops = { + .init = ipt_init_net, + .exit_batch = ipt_exit_net, + .id = &act_ipt_ops.net_id, + .size = sizeof(struct tc_action_net), +}; + +static struct tc_action_ops act_xt_ops = { + .kind = "xt", + .id = TCA_ID_XT, + .owner = THIS_MODULE, + .act = tcf_ipt_act, + .dump = tcf_ipt_dump, + .cleanup = tcf_ipt_release, + .init = tcf_xt_init, + .size = sizeof(struct tcf_ipt), +}; + +static __net_init int xt_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, act_xt_ops.net_id); + + return tc_action_net_init(net, tn, &act_xt_ops); +} + +static void __net_exit xt_exit_net(struct list_head *net_list) +{ + tc_action_net_exit(net_list, act_xt_ops.net_id); +} + +static struct pernet_operations xt_net_ops = { + .init = xt_init_net, + .exit_batch = xt_exit_net, + .id = &act_xt_ops.net_id, + .size = sizeof(struct tc_action_net), +}; + +MODULE_AUTHOR("Jamal Hadi Salim(2002-13)"); +MODULE_DESCRIPTION("Iptables target actions"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("act_xt"); + +static int __init ipt_init_module(void) +{ + int ret1, ret2; + + ret1 = tcf_register_action(&act_xt_ops, &xt_net_ops); + if (ret1 < 0) + pr_err("Failed to load xt action\n"); + + ret2 = tcf_register_action(&act_ipt_ops, &ipt_net_ops); + if (ret2 < 0) + pr_err("Failed to load ipt action\n"); + + if (ret1 < 0 && ret2 < 0) { + return ret1; + } else + return 0; +} + +static void __exit ipt_cleanup_module(void) +{ + tcf_unregister_action(&act_ipt_ops, &ipt_net_ops); + tcf_unregister_action(&act_xt_ops, &xt_net_ops); +} + +module_init(ipt_init_module); +module_exit(ipt_cleanup_module); |