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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /net/sched/act_pedit.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/sched/act_pedit.c')
-rw-r--r-- | net/sched/act_pedit.c | 541 |
1 files changed, 541 insertions, 0 deletions
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c new file mode 100644 index 000000000..aeb8f84cb --- /dev/null +++ b/net/sched/act_pedit.c @@ -0,0 +1,541 @@ +/* + * net/sched/act_pedit.c Generic packet editor + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Jamal Hadi Salim (2002-4) + */ + +#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_pedit.h> +#include <net/tc_act/tc_pedit.h> +#include <uapi/linux/tc_act/tc_pedit.h> + +static unsigned int pedit_net_id; +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_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] = { .type = NLA_U16 }, + [TCA_PEDIT_KEY_EX_CMD] = { .type = NLA_U16 }, +}; + +static struct tcf_pedit_key_ex *tcf_pedit_keys_ex_parse(struct nlattr *nla, + u8 n) +{ + 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 = kcalloc(n, sizeof(*k), GFP_KERNEL); + 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) { + err = -EINVAL; + goto err_out; + } + n--; + + if (nla_type(ka) != TCA_PEDIT_KEY_EX) { + err = -EINVAL; + goto err_out; + } + + err = nla_parse_nested(tb, TCA_PEDIT_KEY_EX_MAX, ka, + pedit_key_ex_policy, NULL); + if (err) + goto err_out; + + if (!tb[TCA_PEDIT_KEY_EX_HTYPE] || + !tb[TCA_PEDIT_KEY_EX_CMD]) { + 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]); + + if (k->htype > TCA_PEDIT_HDR_TYPE_MAX || + k->cmd > TCA_PEDIT_CMD_MAX) { + err = -EINVAL; + goto err_out; + } + + k++; + } + + if (n) { + 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(skb, TCA_PEDIT_KEYS_EX); + + if (!keys_start) + goto nla_failure; + for (; n > 0; n--) { + struct nlattr *key_start; + + key_start = nla_nest_start(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 int tcf_pedit_init(struct net *net, struct nlattr *nla, + struct nlattr *est, struct tc_action **a, + int ovr, int bind, bool rtnl_held, + struct netlink_ext_ack *extack) +{ + struct tc_action_net *tn = net_generic(net, pedit_net_id); + struct nlattr *tb[TCA_PEDIT_MAX + 1]; + struct tc_pedit_key *keys = NULL; + struct tcf_pedit_key_ex *keys_ex; + 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(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); + if (!parm->nkeys) { + NL_SET_ERR_MSG_MOD(extack, "Pedit requires keys to be passed"); + return -EINVAL; + } + 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"); + return -EINVAL; + } + + keys_ex = tcf_pedit_keys_ex_parse(tb[TCA_PEDIT_KEYS_EX], parm->nkeys); + if (IS_ERR(keys_ex)) + return PTR_ERR(keys_ex); + + index = parm->index; + err = tcf_idr_check_alloc(tn, &index, a, bind); + if (!err) { + ret = tcf_idr_create(tn, index, est, a, + &act_pedit_ops, bind, false); + if (ret) { + tcf_idr_cleanup(tn, index); + goto out_free; + } + ret = ACT_P_CREATED; + } else if (err > 0) { + if (bind) + goto out_free; + if (!ovr) { + ret = -EEXIST; + goto out_release; + } + } else { + ret = err; + goto out_free; + } + + p = to_pedit(*a); + spin_lock_bh(&p->tcf_lock); + + if (ret == ACT_P_CREATED || + (p->tcfp_nkeys && p->tcfp_nkeys != parm->nkeys)) { + keys = kmalloc(ksize, GFP_ATOMIC); + if (!keys) { + spin_unlock_bh(&p->tcf_lock); + ret = -ENOMEM; + goto out_release; + } + kfree(p->tcfp_keys); + p->tcfp_keys = keys; + p->tcfp_nkeys = parm->nkeys; + } + memcpy(p->tcfp_keys, parm->keys, ksize); + p->tcfp_off_max_hint = 0; + for (i = 0; i < p->tcfp_nkeys; ++i) { + u32 cur = p->tcfp_keys[i].off; + + /* sanitize the shift value for any later use */ + p->tcfp_keys[i].shift = min_t(size_t, BITS_PER_TYPE(int) - 1, + p->tcfp_keys[i].shift); + + /* The AT option can read a single byte, we can bound the actual + * value with uchar max. + */ + cur += (0xff & p->tcfp_keys[i].offmask) >> p->tcfp_keys[i].shift; + + /* Each key touches 4 bytes starting from the computed offset */ + p->tcfp_off_max_hint = max(p->tcfp_off_max_hint, cur + 4); + } + + p->tcfp_flags = parm->flags; + p->tcf_action = parm->action; + + kfree(p->tcfp_keys_ex); + p->tcfp_keys_ex = keys_ex; + + spin_unlock_bh(&p->tcf_lock); + if (ret == ACT_P_CREATED) + tcf_idr_insert(tn, *a); + return ret; + +out_release: + tcf_idr_release(*a, bind); +out_free: + kfree(keys_ex); + return ret; + +} + +static void tcf_pedit_cleanup(struct tc_action *a) +{ + struct tcf_pedit *p = to_pedit(a); + struct tc_pedit_key *keys = p->tcfp_keys; + + kfree(keys); + kfree(p->tcfp_keys_ex); +} + +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_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: + case TCA_PEDIT_KEY_EX_HDR_TYPE_UDP: + if (skb_transport_header_was_set(skb)) { + *hoffset = skb_transport_offset(skb); + ret = 0; + } + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static int tcf_pedit_act(struct sk_buff *skb, const struct tc_action *a, + struct tcf_result *res) +{ + struct tcf_pedit *p = to_pedit(a); + u32 max_offset; + int i; + + spin_lock(&p->tcf_lock); + + max_offset = (skb_transport_header_was_set(skb) ? + skb_transport_offset(skb) : + skb_network_offset(skb)) + + p->tcfp_off_max_hint; + if (skb_ensure_writable(skb, min(skb->len, max_offset))) + goto unlock; + + tcf_lastuse_update(&p->tcf_tm); + + if (p->tcfp_nkeys > 0) { + struct tc_pedit_key *tkey = p->tcfp_keys; + struct tcf_pedit_key_ex *tkey_ex = p->tcfp_keys_ex; + enum pedit_header_type htype = + TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK; + enum pedit_cmd cmd = TCA_PEDIT_KEY_EX_CMD_SET; + + for (i = p->tcfp_nkeys; i > 0; i--, tkey++) { + u32 *ptr, hdata; + int offset = tkey->off; + int hoffset; + 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("tc action pedit bad header type specified (0x%x)\n", + htype); + goto bad; + } + + if (tkey->offmask) { + u8 *d, _d; + + if (!offset_valid(skb, hoffset + tkey->at)) { + pr_info("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("tc action pedit offset must be on 32 bit boundaries\n"); + goto bad; + } + + if (!offset_valid(skb, hoffset + offset)) { + pr_info("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; + /* just do it, baby */ + 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("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; + } else { + WARN(1, "pedit BUG: index %d\n", p->tcf_index); + } + +bad: + p->tcf_qstats.overlimits++; +done: + bstats_update(&p->tcf_bstats, skb); +unlock: + spin_unlock(&p->tcf_lock); + return p->tcf_action; +} + +static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a, + int bind, int ref) +{ + unsigned char *b = skb_tail_pointer(skb); + struct tcf_pedit *p = to_pedit(a); + struct tc_pedit *opt; + struct tcf_t t; + int s; + + s = sizeof(*opt) + p->tcfp_nkeys * sizeof(struct tc_pedit_key); + + /* netlink spinlocks held above us - must use ATOMIC */ + opt = kzalloc(s, GFP_ATOMIC); + if (unlikely(!opt)) + return -ENOBUFS; + + spin_lock_bh(&p->tcf_lock); + memcpy(opt->keys, p->tcfp_keys, + p->tcfp_nkeys * sizeof(struct tc_pedit_key)); + opt->index = p->tcf_index; + opt->nkeys = p->tcfp_nkeys; + opt->flags = p->tcfp_flags; + opt->action = p->tcf_action; + opt->refcnt = refcount_read(&p->tcf_refcnt) - ref; + opt->bindcnt = atomic_read(&p->tcf_bindcnt) - bind; + + if (p->tcfp_keys_ex) { + if (tcf_pedit_key_ex_dump(skb, + p->tcfp_keys_ex, + p->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; + spin_unlock_bh(&p->tcf_lock); + + kfree(opt); + return skb->len; + +nla_put_failure: + spin_unlock_bh(&p->tcf_lock); + nlmsg_trim(skb, b); + kfree(opt); + return -1; +} + +static int tcf_pedit_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, pedit_net_id); + + return tcf_generic_walker(tn, skb, cb, type, ops, extack); +} + +static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index, + struct netlink_ext_ack *extack) +{ + struct tc_action_net *tn = net_generic(net, pedit_net_id); + + return tcf_idr_search(tn, a, index); +} + +static struct tc_action_ops act_pedit_ops = { + .kind = "pedit", + .type = TCA_ACT_PEDIT, + .owner = THIS_MODULE, + .act = tcf_pedit_act, + .dump = tcf_pedit_dump, + .cleanup = tcf_pedit_cleanup, + .init = tcf_pedit_init, + .walk = tcf_pedit_walker, + .lookup = tcf_pedit_search, + .size = sizeof(struct tcf_pedit), +}; + +static __net_init int pedit_init_net(struct net *net) +{ + struct tc_action_net *tn = net_generic(net, pedit_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, pedit_net_id); +} + +static struct pernet_operations pedit_net_ops = { + .init = pedit_init_net, + .exit_batch = pedit_exit_net, + .id = &pedit_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); |