act_tunnel_key.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2016, Amir Vadai <amir@vadai.me>
* Copyright (c) 2016, Mellanox Technologies. All rights reserved.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <net/geneve.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/dst.h>
#include <net/pkt_cls.h>
#include <linux/tc_act/tc_tunnel_key.h>
#include <net/tc_act/tc_tunnel_key.h>
static unsigned int tunnel_key_net_id;
static struct tc_action_ops act_tunnel_key_ops;
static int tunnel_key_act(struct sk_buff *skb, const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_tunnel_key *t = to_tunnel_key(a);
struct tcf_tunnel_key_params *params;
int action;
params = rcu_dereference_bh(t->params);
tcf_lastuse_update(&t->tcf_tm);
bstats_cpu_update(this_cpu_ptr(t->common.cpu_bstats), skb);
action = READ_ONCE(t->tcf_action);
switch (params->tcft_action) {
case TCA_TUNNEL_KEY_ACT_RELEASE:
skb_dst_drop(skb);
break;
case TCA_TUNNEL_KEY_ACT_SET:
skb_dst_drop(skb);
skb_dst_set(skb, dst_clone(¶ms->tcft_enc_metadata->dst));
break;
default:
WARN_ONCE(1, "Bad tunnel_key action %d.\n",
params->tcft_action);
break;
}
return action;
}
static const struct nla_policy
enc_opts_policy[TCA_TUNNEL_KEY_ENC_OPTS_MAX + 1] = {
[TCA_TUNNEL_KEY_ENC_OPTS_GENEVE] = { .type = NLA_NESTED },
};
static const struct nla_policy
geneve_opt_policy[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX + 1] = {
[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_CLASS] = { .type = NLA_U16 },
[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_TYPE] = { .type = NLA_U8 },
[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA] = { .type = NLA_BINARY,
.len = 128 },
};
static int
tunnel_key_copy_geneve_opt(const struct nlattr *nla, void *dst, int dst_len,
struct netlink_ext_ack *extack)
{
struct nlattr *tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX + 1];
int err, data_len, opt_len;
u8 *data;
err = nla_parse_nested_deprecated(tb,
TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX,
nla, geneve_opt_policy, extack);
if (err < 0)
return err;
if (!tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_CLASS] ||
!tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_TYPE] ||
!tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA]) {
NL_SET_ERR_MSG(extack, "Missing tunnel key geneve option class, type or data");
return -EINVAL;
}
data = nla_data(tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA]);
data_len = nla_len(tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA]);
if (data_len < 4) {
NL_SET_ERR_MSG(extack, "Tunnel key geneve option data is less than 4 bytes long");
return -ERANGE;
}
if (data_len % 4) {
NL_SET_ERR_MSG(extack, "Tunnel key geneve option data is not a multiple of 4 bytes long");
return -ERANGE;
}
opt_len = sizeof(struct geneve_opt) + data_len;
if (dst) {
struct geneve_opt *opt = dst;
WARN_ON(dst_len < opt_len);
opt->opt_class =
nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_CLASS]);
opt->type = nla_get_u8(tb[TCA_TUNNEL_KEY_ENC_OPT_GENEVE_TYPE]);
opt->length = data_len / 4; /* length is in units of 4 bytes */
opt->r1 = 0;
opt->r2 = 0;
opt->r3 = 0;
memcpy(opt + 1, data, data_len);
}
return opt_len;
}
static int tunnel_key_copy_opts(const struct nlattr *nla, u8 *dst,
int dst_len, struct netlink_ext_ack *extack)
{
int err, rem, opt_len, len = nla_len(nla), opts_len = 0;
const struct nlattr *attr, *head = nla_data(nla);
err = nla_validate_deprecated(head, len, TCA_TUNNEL_KEY_ENC_OPTS_MAX,
enc_opts_policy, extack);
if (err)
return err;
nla_for_each_attr(attr, head, len, rem) {
switch (nla_type(attr)) {
case TCA_TUNNEL_KEY_ENC_OPTS_GENEVE:
opt_len = tunnel_key_copy_geneve_opt(attr, dst,
dst_len, extack);
if (opt_len < 0)
return opt_len;
opts_len += opt_len;
if (dst) {
dst_len -= opt_len;
dst += opt_len;
}
break;
}
}
if (!opts_len) {
NL_SET_ERR_MSG(extack, "Empty list of tunnel options");
return -EINVAL;
}
if (rem > 0) {
NL_SET_ERR_MSG(extack, "Trailing data after parsing tunnel key options attributes");
return -EINVAL;
}
return opts_len;
}
static int tunnel_key_get_opts_len(struct nlattr *nla,
struct netlink_ext_ack *extack)
{
return tunnel_key_copy_opts(nla, NULL, 0, extack);
}
static int tunnel_key_opts_set(struct nlattr *nla, struct ip_tunnel_info *info,
int opts_len, struct netlink_ext_ack *extack)
{
info->options_len = opts_len;
switch (nla_type(nla_data(nla))) {
case TCA_TUNNEL_KEY_ENC_OPTS_GENEVE:
#if IS_ENABLED(CONFIG_INET)
info->key.tun_flags |= TUNNEL_GENEVE_OPT;
return tunnel_key_copy_opts(nla, ip_tunnel_info_opts(info),
opts_len, extack);
#else
return -EAFNOSUPPORT;
#endif
default:
NL_SET_ERR_MSG(extack, "Cannot set tunnel options for unknown tunnel type");
return -EINVAL;
}
}
static const struct nla_policy tunnel_key_policy[TCA_TUNNEL_KEY_MAX + 1] = {
[TCA_TUNNEL_KEY_PARMS] = { .len = sizeof(struct tc_tunnel_key) },
[TCA_TUNNEL_KEY_ENC_IPV4_SRC] = { .type = NLA_U32 },
[TCA_TUNNEL_KEY_ENC_IPV4_DST] = { .type = NLA_U32 },
[TCA_TUNNEL_KEY_ENC_IPV6_SRC] = { .len = sizeof(struct in6_addr) },
[TCA_TUNNEL_KEY_ENC_IPV6_DST] = { .len = sizeof(struct in6_addr) },
[TCA_TUNNEL_KEY_ENC_KEY_ID] = { .type = NLA_U32 },
[TCA_TUNNEL_KEY_ENC_DST_PORT] = {.type = NLA_U16},
[TCA_TUNNEL_KEY_NO_CSUM] = { .type = NLA_U8 },
[TCA_TUNNEL_KEY_ENC_OPTS] = { .type = NLA_NESTED },
[TCA_TUNNEL_KEY_ENC_TOS] = { .type = NLA_U8 },
[TCA_TUNNEL_KEY_ENC_TTL] = { .type = NLA_U8 },
};
static void tunnel_key_release_params(struct tcf_tunnel_key_params *p)
{
if (!p)
return;
if (p->tcft_action == TCA_TUNNEL_KEY_ACT_SET)
dst_release(&p->tcft_enc_metadata->dst);
kfree_rcu(p, rcu);
}
static int tunnel_key_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a,
int ovr, int bind, bool rtnl_held,
struct tcf_proto *tp,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
struct nlattr *tb[TCA_TUNNEL_KEY_MAX + 1];
struct tcf_tunnel_key_params *params_new;
struct metadata_dst *metadata = NULL;
struct tcf_chain *goto_ch = NULL;
struct tc_tunnel_key *parm;
struct tcf_tunnel_key *t;
bool exists = false;
__be16 dst_port = 0;
__be64 key_id = 0;
int opts_len = 0;
__be16 flags = 0;
u8 tos, ttl;
int ret = 0;
u32 index;
int err;
if (!nla) {
NL_SET_ERR_MSG(extack, "Tunnel requires attributes to be passed");
return -EINVAL;
}
err = nla_parse_nested_deprecated(tb, TCA_TUNNEL_KEY_MAX, nla,
tunnel_key_policy, extack);
if (err < 0) {
NL_SET_ERR_MSG(extack, "Failed to parse nested tunnel key attributes");
return err;
}
if (!tb[TCA_TUNNEL_KEY_PARMS]) {
NL_SET_ERR_MSG(extack, "Missing tunnel key parameters");
return -EINVAL;
}
parm = nla_data(tb[TCA_TUNNEL_KEY_PARMS]);
index = parm->index;
err = tcf_idr_check_alloc(tn, &index, a, bind);
if (err < 0)
return err;
exists = err;
if (exists && bind)
return 0;
switch (parm->t_action) {
case TCA_TUNNEL_KEY_ACT_RELEASE:
break;
case TCA_TUNNEL_KEY_ACT_SET:
if (tb[TCA_TUNNEL_KEY_ENC_KEY_ID]) {
__be32 key32;
key32 = nla_get_be32(tb[TCA_TUNNEL_KEY_ENC_KEY_ID]);
key_id = key32_to_tunnel_id(key32);
flags = TUNNEL_KEY;
}
flags |= TUNNEL_CSUM;
if (tb[TCA_TUNNEL_KEY_NO_CSUM] &&
nla_get_u8(tb[TCA_TUNNEL_KEY_NO_CSUM]))
flags &= ~TUNNEL_CSUM;
if (tb[TCA_TUNNEL_KEY_ENC_DST_PORT])
dst_port = nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_DST_PORT]);
if (tb[TCA_TUNNEL_KEY_ENC_OPTS]) {
opts_len = tunnel_key_get_opts_len(tb[TCA_TUNNEL_KEY_ENC_OPTS],
extack);
if (opts_len < 0) {
ret = opts_len;
goto err_out;
}
}
tos = 0;
if (tb[TCA_TUNNEL_KEY_ENC_TOS])
tos = nla_get_u8(tb[TCA_TUNNEL_KEY_ENC_TOS]);
ttl = 0;
if (tb[TCA_TUNNEL_KEY_ENC_TTL])
ttl = nla_get_u8(tb[TCA_TUNNEL_KEY_ENC_TTL]);
if (tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC] &&
tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]) {
__be32 saddr;
__be32 daddr;
saddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC]);
daddr = nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]);
metadata = __ip_tun_set_dst(saddr, daddr, tos, ttl,
dst_port, flags,
key_id, opts_len);
} else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
struct in6_addr saddr;
struct in6_addr daddr;
saddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC]);
daddr = nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]);
metadata = __ipv6_tun_set_dst(&saddr, &daddr, tos, ttl, dst_port,
0, flags,
key_id, 0);
} else {
NL_SET_ERR_MSG(extack, "Missing either ipv4 or ipv6 src and dst");
ret = -EINVAL;
goto err_out;
}
if (!metadata) {
NL_SET_ERR_MSG(extack, "Cannot allocate tunnel metadata dst");
ret = -ENOMEM;
goto err_out;
}
#ifdef CONFIG_DST_CACHE
ret = dst_cache_init(&metadata->u.tun_info.dst_cache, GFP_KERNEL);
if (ret)
goto release_tun_meta;
#endif
if (opts_len) {
ret = tunnel_key_opts_set(tb[TCA_TUNNEL_KEY_ENC_OPTS],
&metadata->u.tun_info,
opts_len, extack);
if (ret < 0)
goto release_tun_meta;
}
metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX;
break;
default:
NL_SET_ERR_MSG(extack, "Unknown tunnel key action");
ret = -EINVAL;
goto err_out;
}
if (!exists) {
ret = tcf_idr_create(tn, index, est, a,
&act_tunnel_key_ops, bind, true);
if (ret) {
NL_SET_ERR_MSG(extack, "Cannot create TC IDR");
goto release_tun_meta;
}
ret = ACT_P_CREATED;
} else if (!ovr) {
NL_SET_ERR_MSG(extack, "TC IDR already exists");
ret = -EEXIST;
goto release_tun_meta;
}
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0) {
ret = err;
exists = true;
goto release_tun_meta;
}
t = to_tunnel_key(*a);
params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
if (unlikely(!params_new)) {
NL_SET_ERR_MSG(extack, "Cannot allocate tunnel key parameters");
ret = -ENOMEM;
exists = true;
goto put_chain;
}
params_new->tcft_action = parm->t_action;
params_new->tcft_enc_metadata = metadata;
spin_lock_bh(&t->tcf_lock);
goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
rcu_swap_protected(t->params, params_new,
lockdep_is_held(&t->tcf_lock));
spin_unlock_bh(&t->tcf_lock);
tunnel_key_release_params(params_new);
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
if (ret == ACT_P_CREATED)
tcf_idr_insert(tn, *a);
return ret;
put_chain:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
release_tun_meta:
if (metadata)
dst_release(&metadata->dst);
err_out:
if (exists)
tcf_idr_release(*a, bind);
else
tcf_idr_cleanup(tn, index);
return ret;
}
static void tunnel_key_release(struct tc_action *a)
{
struct tcf_tunnel_key *t = to_tunnel_key(a);
struct tcf_tunnel_key_params *params;
params = rcu_dereference_protected(t->params, 1);
tunnel_key_release_params(params);
}
static int tunnel_key_geneve_opts_dump(struct sk_buff *skb,
const struct ip_tunnel_info *info)
{
int len = info->options_len;
u8 *src = (u8 *)(info + 1);
struct nlattr *start;
start = nla_nest_start_noflag(skb, TCA_TUNNEL_KEY_ENC_OPTS_GENEVE);
if (!start)
return -EMSGSIZE;
while (len > 0) {
struct geneve_opt *opt = (struct geneve_opt *)src;
if (nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_OPT_GENEVE_CLASS,
opt->opt_class) ||
nla_put_u8(skb, TCA_TUNNEL_KEY_ENC_OPT_GENEVE_TYPE,
opt->type) ||
nla_put(skb, TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA,
opt->length * 4, opt + 1)) {
nla_nest_cancel(skb, start);
return -EMSGSIZE;
}
len -= sizeof(struct geneve_opt) + opt->length * 4;
src += sizeof(struct geneve_opt) + opt->length * 4;
}
nla_nest_end(skb, start);
return 0;
}
static int tunnel_key_opts_dump(struct sk_buff *skb,
const struct ip_tunnel_info *info)
{
struct nlattr *start;
int err = -EINVAL;
if (!info->options_len)
return 0;
start = nla_nest_start_noflag(skb, TCA_TUNNEL_KEY_ENC_OPTS);
if (!start)
return -EMSGSIZE;
if (info->key.tun_flags & TUNNEL_GENEVE_OPT) {
err = tunnel_key_geneve_opts_dump(skb, info);
if (err)
goto err_out;
} else {
err_out:
nla_nest_cancel(skb, start);
return err;
}
nla_nest_end(skb, start);
return 0;
}
static int tunnel_key_dump_addresses(struct sk_buff *skb,
const struct ip_tunnel_info *info)
{
unsigned short family = ip_tunnel_info_af(info);
if (family == AF_INET) {
__be32 saddr = info->key.u.ipv4.src;
__be32 daddr = info->key.u.ipv4.dst;
if (!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_SRC, saddr) &&
!nla_put_in_addr(skb, TCA_TUNNEL_KEY_ENC_IPV4_DST, daddr))
return 0;
}
if (family == AF_INET6) {
const struct in6_addr *saddr6 = &info->key.u.ipv6.src;
const struct in6_addr *daddr6 = &info->key.u.ipv6.dst;
if (!nla_put_in6_addr(skb,
TCA_TUNNEL_KEY_ENC_IPV6_SRC, saddr6) &&
!nla_put_in6_addr(skb,
TCA_TUNNEL_KEY_ENC_IPV6_DST, daddr6))
return 0;
}
return -EINVAL;
}
static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_tunnel_key *t = to_tunnel_key(a);
struct tcf_tunnel_key_params *params;
struct tc_tunnel_key opt = {
.index = t->tcf_index,
.refcnt = refcount_read(&t->tcf_refcnt) - ref,
.bindcnt = atomic_read(&t->tcf_bindcnt) - bind,
};
struct tcf_t tm;
spin_lock_bh(&t->tcf_lock);
params = rcu_dereference_protected(t->params,
lockdep_is_held(&t->tcf_lock));
opt.action = t->tcf_action;
opt.t_action = params->tcft_action;
if (nla_put(skb, TCA_TUNNEL_KEY_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
struct ip_tunnel_info *info =
¶ms->tcft_enc_metadata->u.tun_info;
struct ip_tunnel_key *key = &info->key;
__be32 key_id = tunnel_id_to_key32(key->tun_id);
if (((key->tun_flags & TUNNEL_KEY) &&
nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id)) ||
tunnel_key_dump_addresses(skb,
¶ms->tcft_enc_metadata->u.tun_info) ||
(key->tp_dst &&
nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT,
key->tp_dst)) ||
nla_put_u8(skb, TCA_TUNNEL_KEY_NO_CSUM,
!(key->tun_flags & TUNNEL_CSUM)) ||
tunnel_key_opts_dump(skb, info))
goto nla_put_failure;
if (key->tos && nla_put_u8(skb, TCA_TUNNEL_KEY_ENC_TOS, key->tos))
goto nla_put_failure;
if (key->ttl && nla_put_u8(skb, TCA_TUNNEL_KEY_ENC_TTL, key->ttl))
goto nla_put_failure;
}
tcf_tm_dump(&tm, &t->tcf_tm);
if (nla_put_64bit(skb, TCA_TUNNEL_KEY_TM, sizeof(tm),
&tm, TCA_TUNNEL_KEY_PAD))
goto nla_put_failure;
spin_unlock_bh(&t->tcf_lock);
return skb->len;
nla_put_failure:
spin_unlock_bh(&t->tcf_lock);
nlmsg_trim(skb, b);
return -1;
}
static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
struct netlink_callback *cb, int type,
const struct tc_action_ops *ops,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
return tcf_generic_walker(tn, skb, cb, type, ops, extack);
}
static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
{
struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
return tcf_idr_search(tn, a, index);
}
static struct tc_action_ops act_tunnel_key_ops = {
.kind = "tunnel_key",
.id = TCA_ID_TUNNEL_KEY,
.owner = THIS_MODULE,
.act = tunnel_key_act,
.dump = tunnel_key_dump,
.init = tunnel_key_init,
.cleanup = tunnel_key_release,
.walk = tunnel_key_walker,
.lookup = tunnel_key_search,
.size = sizeof(struct tcf_tunnel_key),
};
static __net_init int tunnel_key_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
return tc_action_net_init(tn, &act_tunnel_key_ops);
}
static void __net_exit tunnel_key_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, tunnel_key_net_id);
}
static struct pernet_operations tunnel_key_net_ops = {
.init = tunnel_key_init_net,
.exit_batch = tunnel_key_exit_net,
.id = &tunnel_key_net_id,
.size = sizeof(struct tc_action_net),
};
static int __init tunnel_key_init_module(void)
{
return tcf_register_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
}
static void __exit tunnel_key_cleanup_module(void)
{
tcf_unregister_action(&act_tunnel_key_ops, &tunnel_key_net_ops);
}
module_init(tunnel_key_init_module);
module_exit(tunnel_key_cleanup_module);
MODULE_AUTHOR("Amir Vadai <amir@vadai.me>");
MODULE_DESCRIPTION("ip tunnel manipulation actions");
MODULE_LICENSE("GPL v2");