#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/ip.h>
#include <linux/ipv6.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <linux/tc_act/tc_pedit.h>
#include <net/tc_act/tc_pedit.h>
#include <uapi/linux/tc_act/tc_pedit.h>
#include <net/pkt_cls.h>
#include <net/tc_wrapper.h>
static struct tc_action_ops act_pedit_ops;
static const struct nla_policy pedit_policy[TCA_PEDIT_MAX + 1] = {
[TCA_PEDIT_PARMS] = { .len = sizeof(struct tc_pedit) },
[TCA_PEDIT_PARMS_EX] = { .len = sizeof(struct tc_pedit) },
[TCA_PEDIT_KEYS_EX] = { .type = NLA_NESTED },
};
static const struct nla_policy pedit_key_ex_policy[TCA_PEDIT_KEY_EX_MAX + 1] = {
[TCA_PEDIT_KEY_EX_HTYPE] =
NLA_POLICY_MAX(NLA_U16, TCA_PEDIT_HDR_TYPE_MAX),
[TCA_PEDIT_KEY_EX_CMD] = NLA_POLICY_MAX(NLA_U16, TCA_PEDIT_CMD_MAX),
};
static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla,
u8 n, struct netlink_ext_ack *extack)
{
struct tcf_pedit_key_ex *keys_ex;
struct tcf_pedit_key_ex *k;
const struct nlattr *ka;
int err = -EINVAL;
int rem;
if (!nla)
return NULL;
keys_ex = kzalloc_objs(*k, n);
if (!keys_ex)
return ERR_PTR(-ENOMEM);
k = keys_ex;
nla_for_each_nested(ka, nla, rem) {
struct nlattr *tb[TCA_PEDIT_KEY_EX_MAX + 1];
if (!n) {
NL_SET_ERR_MSG_MOD(extack, "Can't parse more extended keys than requested");
err = -EINVAL;
goto err_out;
}
n--;
if (nla_type(ka) != TCA_PEDIT_KEY_EX) {
NL_SET_ERR_MSG_ATTR(extack, ka, "Unknown attribute, expected extended key");
err = -EINVAL;
goto err_out;
}
err = nla_parse_nested_deprecated(tb, TCA_PEDIT_KEY_EX_MAX,
ka, pedit_key_ex_policy,
NULL);
if (err)
goto err_out;
if (NL_REQ_ATTR_CHECK(extack, nla, tb, TCA_PEDIT_KEY_EX_HTYPE)) {
NL_SET_ERR_MSG(extack, "Missing required attribute");
err = -EINVAL;
goto err_out;
}
if (NL_REQ_ATTR_CHECK(extack, nla, tb, TCA_PEDIT_KEY_EX_CMD)) {
NL_SET_ERR_MSG(extack, "Missing required attribute");
err = -EINVAL;
goto err_out;
}
k->htype = nla_get_u16(tb[TCA_PEDIT_KEY_EX_HTYPE]);
k->cmd = nla_get_u16(tb[TCA_PEDIT_KEY_EX_CMD]);
k++;
}
if (n) {
NL_SET_ERR_MSG_MOD(extack, "Not enough extended keys to parse");
err = -EINVAL;
goto err_out;
}
return keys_ex;
err_out:
kfree(keys_ex);
return ERR_PTR(err);
}
static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
struct tcf_pedit_key_ex *keys_ex, int n)
{
struct nlattr *keys_start = nla_nest_start_noflag(skb,
TCA_PEDIT_KEYS_EX);
if (!keys_start)
goto nla_failure;
for (; n > 0; n--) {
struct nlattr *key_start;
key_start = nla_nest_start_noflag(skb, TCA_PEDIT_KEY_EX);
if (!key_start)
goto nla_failure;
if (nla_put_u16(skb, TCA_PEDIT_KEY_EX_HTYPE, keys_ex->htype) ||
nla_put_u16(skb, TCA_PEDIT_KEY_EX_CMD, keys_ex->cmd))
goto nla_failure;
nla_nest_end(skb, key_start);
keys_ex++;
}
nla_nest_end(skb, keys_start);
return 0;
nla_failure:
nla_nest_cancel(skb, keys_start);
return -EINVAL;
}
static void tcf_pedit_cleanup_rcu(struct rcu_head *head)
{
struct tcf_pedit_parms *parms =
container_of(head, struct tcf_pedit_parms, rcu);
kfree(parms->tcfp_keys_ex);
kfree(parms->tcfp_keys);
kfree(parms);
}
static int tcf_pedit_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)
{
struct tc_action_net *tn = net_generic(net, act_pedit_ops.net_id);
bool bind = flags & TCA_ACT_FLAGS_BIND;
struct tcf_chain *goto_ch = NULL;
struct tcf_pedit_parms *oparms, *nparms;
struct nlattr *tb[TCA_PEDIT_MAX + 1];
struct tc_pedit *parm;
struct nlattr *pattr;
struct tcf_pedit *p;
int ret = 0, err;
int i, ksize;
u32 index;
if (!nla) {
NL_SET_ERR_MSG_MOD(extack, "Pedit requires attributes to be passed");
return -EINVAL;
}
err = nla_parse_nested_deprecated(tb, TCA_PEDIT_MAX, nla,
pedit_policy, NULL);
if (err < 0)
return err;
pattr = tb[TCA_PEDIT_PARMS];
if (!pattr)
pattr = tb[TCA_PEDIT_PARMS_EX];
if (!pattr) {
NL_SET_ERR_MSG_MOD(extack, "Missing required TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute");
return -EINVAL;
}
parm = nla_data(pattr);
index = parm->index;
err = tcf_idr_check_alloc(tn, &index, a, bind);
if (!err) {
ret = tcf_idr_create_from_flags(tn, index, est, a,
&act_pedit_ops, bind, flags);
if (ret) {
tcf_idr_cleanup(tn, index);
return ret;
}
ret = ACT_P_CREATED;
} else if (err > 0) {
if (bind)
return ACT_P_BOUND;
if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
ret = -EEXIST;
goto out_release;
}
} else {
return err;
}
if (!parm->nkeys) {
NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed");
ret = -EINVAL;
goto out_release;
}
ksize = parm->nkeys * sizeof(struct tc_pedit_key);
if (nla_len(pattr) < sizeof(*parm) + ksize) {
NL_SET_ERR_MSG_ATTR(extack, pattr, "Length of TCA_PEDIT_PARMS or TCA_PEDIT_PARMS_EX pedit attribute is invalid");
ret = -EINVAL;
goto out_release;
}
nparms = kzalloc_obj(*nparms);
if (!nparms) {
ret = -ENOMEM;
goto out_release;
}
nparms->tcfp_keys_ex =
tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys, extack);
if (IS_ERR(nparms->tcfp_keys_ex)) {
ret = PTR_ERR(nparms->tcfp_keys_ex);
goto out_free;
}
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0) {
ret = err;
goto out_free_ex;
}
nparms->tcfp_off_max_hint = 0;
nparms->tcfp_flags = parm->flags;
nparms->tcfp_nkeys = parm->nkeys;
nparms->tcfp_keys = kmemdup(parm->keys, ksize, GFP_KERNEL);
if (!nparms->tcfp_keys) {
ret = -ENOMEM;
goto put_chain;
}
for (i = 0; i < nparms->tcfp_nkeys; ++i) {
u32 offmask = nparms->tcfp_keys[i].offmask;
u32 cur = nparms->tcfp_keys[i].off;
if (!offmask && cur % 4) {
NL_SET_ERR_MSG_MOD(extack, "Offsets must be on 32bit boundaries");
ret = -EINVAL;
goto out_free_keys;
}
nparms->tcfp_keys[i].shift = min_t(size_t,
BITS_PER_TYPE(int) - 1,
nparms->tcfp_keys[i].shift);
cur += (0xff & offmask) >> nparms->tcfp_keys[i].shift;
nparms->tcfp_off_max_hint =
max(nparms->tcfp_off_max_hint, cur + 4);
}
p = to_pedit(*a);
nparms->action = parm->action;
spin_lock_bh(&p->tcf_lock);
goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
oparms = rcu_replace_pointer(p->parms, nparms, 1);
spin_unlock_bh(&p->tcf_lock);
if (oparms)
call_rcu(&oparms->rcu, tcf_pedit_cleanup_rcu);
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
return ret;
out_free_keys:
kfree(nparms->tcfp_keys);
put_chain:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
out_free_ex:
kfree(nparms->tcfp_keys_ex);
out_free:
kfree(nparms);
out_release:
tcf_idr_release(*a, bind);
return ret;
}
static void tcf_pedit_cleanup(struct tc_action *a)
{
struct tcf_pedit *p = to_pedit(a);
struct tcf_pedit_parms *parms;
parms = rcu_dereference_protected(p->parms, 1);
if (parms)
call_rcu(&parms->rcu, tcf_pedit_cleanup_rcu);
}
static bool offset_valid(struct sk_buff *skb, int offset)
{
if (offset > 0 && offset > skb->len)
return false;
if (offset < 0 && -offset > skb_headroom(skb))
return false;
return true;
}
static int pedit_l4_skb_offset(struct sk_buff *skb, int *hoffset, const int header_type)
{
const int noff = skb_network_offset(skb);
int ret = -EINVAL;
struct iphdr _iph;
switch (skb->protocol) {
case htons(ETH_P_IP): {
const struct iphdr *iph = skb_header_pointer(skb, noff, sizeof(_iph), &_iph);
if (!iph)
goto out;
*hoffset = noff + iph->ihl * 4;
ret = 0;
break;
}
case htons(ETH_P_IPV6):
ret = ipv6_find_hdr(skb, hoffset, header_type, NULL, NULL) == header_type ? 0 : -EINVAL;
break;
}
out:
return ret;
}
static int pedit_skb_hdr_offset(struct sk_buff *skb,
enum pedit_header_type htype, int *hoffset)
{
int ret = -EINVAL;
switch (htype) {
case TCA_PEDIT_KEY_EX_HDR_TYPE_ETH:
if (skb_mac_header_was_set(skb)) {
*hoffset = skb_mac_offset(skb);
ret = 0;
}
break;
case TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK:
case TCA_PEDIT_KEY_EX_HDR_TYPE_IP4:
case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
*hoffset = skb_network_offset(skb);
ret = 0;
break;
case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
ret = pedit_l4_skb_offset(skb, hoffset, IPPROTO_TCP);
break;
case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP:
ret = pedit_l4_skb_offset(skb, hoffset, IPPROTO_UDP);
break;
default:
break;
}
return ret;
}
TC_INDIRECT_SCOPE int tcf_pedit_act(struct sk_buff *skb,
const struct tc_action *a,
struct tcf_result *res)
{
enum pedit_header_type htype = TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK;
enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET;
struct tcf_pedit *p = to_pedit(a);
struct tcf_pedit_key_ex *tkey_ex;
struct tcf_pedit_parms *parms;
struct tc_pedit_key *tkey;
u32 max_offset;
int i;
parms = rcu_dereference_bh(p->parms);
max_offset = (skb_transport_header_was_set(skb) ?
skb_transport_offset(skb) :
skb_network_offset(skb)) +
parms->tcfp_off_max_hint;
if (skb_ensure_writable(skb, min(skb->len, max_offset)))
goto done;
tcf_lastuse_update(&p->tcf_tm);
tcf_action_update_bstats(&p->common, skb);
tkey = parms->tcfp_keys;
tkey_ex = parms->tcfp_keys_ex;
for (i = parms->tcfp_nkeys; i > 0; i--, tkey++) {
int offset = tkey->off;
int hoffset = 0;
u32 *ptr, hdata;
u32 val;
int rc;
if (tkey_ex) {
htype = tkey_ex->htype;
cmd = tkey_ex->cmd;
tkey_ex++;
}
rc = pedit_skb_hdr_offset(skb, htype, &hoffset);
if (rc) {
pr_info_ratelimited("tc action pedit unable to extract header offset for header type (0x%x)\n", htype);
goto bad;
}
if (tkey->offmask) {
u8 *d, _d;
if (!offset_valid(skb, hoffset + tkey->at)) {
pr_info_ratelimited("tc action pedit 'at' offset %d out of bounds\n",
hoffset + tkey->at);
goto bad;
}
d = skb_header_pointer(skb, hoffset + tkey->at,
sizeof(_d), &_d);
if (!d)
goto bad;
offset += (*d & tkey->offmask) >> tkey->shift;
if (offset % 4) {
pr_info_ratelimited("tc action pedit offset must be on 32 bit boundaries\n");
goto bad;
}
}
if (!offset_valid(skb, hoffset + offset)) {
pr_info_ratelimited("tc action pedit offset %d out of bounds\n", hoffset + offset);
goto bad;
}
ptr = skb_header_pointer(skb, hoffset + offset,
sizeof(hdata), &hdata);
if (!ptr)
goto bad;
switch (cmd) {
case TCA_PEDIT_KEY_EX_CMD_SET:
val = tkey->val;
break;
case TCA_PEDIT_KEY_EX_CMD_ADD:
val = (*ptr + tkey->val) & ~tkey->mask;
break;
default:
pr_info_ratelimited("tc action pedit bad command (%d)\n", cmd);
goto bad;
}
*ptr = ((*ptr & tkey->mask) ^ val);
if (ptr == &hdata)
skb_store_bits(skb, hoffset + offset, ptr, 4);
}
goto done;
bad:
tcf_action_inc_overlimit_qstats(&p->common);
done:
return parms->action;
}
static void tcf_pedit_stats_update(struct tc_action *a, u64 bytes, u64 packets,
u64 drops, u64 lastuse, bool hw)
{
struct tcf_pedit *d = to_pedit(a);
struct tcf_t *tm = &d->tcf_tm;
tcf_action_update_stats(a, bytes, packets, drops, hw);
tm->lastuse = max_t(u64, tm->lastuse, lastuse);
}
static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
const struct tcf_pedit *p = to_pedit(a);
const struct tcf_pedit_parms *parms;
struct tc_pedit *opt;
struct tcf_t t;
int s;
rcu_read_lock();
parms = rcu_dereference(p->parms);
s = struct_size(opt, keys, parms->tcfp_nkeys);
opt = kzalloc(s, GFP_ATOMIC);
if (unlikely(!opt)) {
rcu_read_unlock();
return -ENOBUFS;
}
opt->nkeys = parms->tcfp_nkeys;
memcpy(opt->keys, parms->tcfp_keys,
flex_array_size(opt, keys, parms->tcfp_nkeys));
opt->index = p->tcf_index;
opt->flags = parms->tcfp_flags;
opt->action = parms->action;
opt->refcnt = refcount_read(&p->tcf_refcnt) - ref;
opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind;
if (parms->tcfp_keys_ex) {
if (tcf_pedit_key_ex_dump(skb, parms->tcfp_keys_ex,
parms->tcfp_nkeys))
goto nla_put_failure;
if (nla_put(skb, TCA_PEDIT_PARMS_EX, s, opt))
goto nla_put_failure;
} else {
if (nla_put(skb, TCA_PEDIT_PARMS, s, opt))
goto nla_put_failure;
}
tcf_tm_dump(&t, &p->tcf_tm);
if (nla_put_64bit(skb, TCA_PEDIT_TM, sizeof(t), &t, TCA_PEDIT_PAD))
goto nla_put_failure;
rcu_read_unlock();
kfree(opt);
return skb->len;
nla_put_failure:
rcu_read_unlock();
nlmsg_trim(skb, b);
kfree(opt);
return -1;
}
static int tcf_pedit_offload_act_setup(struct tc_action *act, void *entry_data,
u32 *index_inc, bool bind,
struct netlink_ext_ack *extack)
{
if (bind) {
struct flow_action_entry *entry = entry_data;
int k;
for (k = 0; k < tcf_pedit_nkeys(act); k++) {
switch (tcf_pedit_cmd(act, k)) {
case TCA_PEDIT_KEY_EX_CMD_SET:
entry->id = FLOW_ACTION_MANGLE;
break;
case TCA_PEDIT_KEY_EX_CMD_ADD:
entry->id = FLOW_ACTION_ADD;
break;
default:
NL_SET_ERR_MSG_MOD(extack, "Unsupported pedit command offload");
return -EOPNOTSUPP;
}
entry->mangle.htype = tcf_pedit_htype(act, k);
entry->mangle.mask = tcf_pedit_mask(act, k);
entry->mangle.val = tcf_pedit_val(act, k);
entry->mangle.offset = tcf_pedit_offset(act, k);
entry->hw_stats = tc_act_hw_stats(act->hw_stats);
entry++;
}
*index_inc = k;
} else {
struct flow_offload_action *fl_action = entry_data;
u32 cmd = tcf_pedit_cmd(act, 0);
int k;
switch (cmd) {
case TCA_PEDIT_KEY_EX_CMD_SET:
fl_action->id = FLOW_ACTION_MANGLE;
break;
case TCA_PEDIT_KEY_EX_CMD_ADD:
fl_action->id = FLOW_ACTION_ADD;
break;
default:
NL_SET_ERR_MSG_MOD(extack, "Unsupported pedit command offload");
return -EOPNOTSUPP;
}
for (k = 1; k < tcf_pedit_nkeys(act); k++) {
if (cmd != tcf_pedit_cmd(act, k)) {
NL_SET_ERR_MSG_MOD(extack, "Unsupported pedit command offload");
return -EOPNOTSUPP;
}
}
}
return 0;
}
static struct tc_action_ops act_pedit_ops = {
.kind = "pedit",
.id = TCA_ID_PEDIT,
.owner = THIS_MODULE,
.act = tcf_pedit_act,
.stats_update = tcf_pedit_stats_update,
.dump = tcf_pedit_dump,
.cleanup = tcf_pedit_cleanup,
.init = tcf_pedit_init,
.offload_act_setup = tcf_pedit_offload_act_setup,
.size = sizeof(struct tcf_pedit),
};
MODULE_ALIAS_NET_ACT("pedit");
static __net_init int pedit_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, act_pedit_ops.net_id);
return tc_action_net_init(net, tn, &act_pedit_ops);
}
static void __net_exit pedit_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, act_pedit_ops.net_id);
}
static struct pernet_operations pedit_net_ops = {
.init = pedit_init_net,
.exit_batch = pedit_exit_net,
.id = &act_pedit_ops.net_id,
.size = sizeof(struct tc_action_net),
};
MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Generic Packet Editor actions");
MODULE_LICENSE("GPL");
static int __init pedit_init_module(void)
{
return tcf_register_action(&act_pedit_ops, &pedit_net_ops);
}
static void __exit pedit_cleanup_module(void)
{
tcf_unregister_action(&act_pedit_ops, &pedit_net_ops);
}
module_init(pedit_init_module);
module_exit(pedit_cleanup_module);
