From c9626a2cbdb20e26587b3fad99960520a023432b Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 9 Jul 2019 23:00:43 +0200 Subject: netfilter: nf_tables: add hardware offload support This patch adds hardware offload support for nftables through the existing netdev_ops->ndo_setup_tc() interface, the TC_SETUP_CLSFLOWER classifier and the flow rule API. This hardware offload support is available for the NFPROTO_NETDEV family and the ingress hook. Each nftables expression has a new ->offload interface, that is used to populate the flow rule object that is attached to the transaction object. There is a new per-table NFT_TABLE_F_HW flag, that is set on to offload an entire table, including all of its chains. This patch supports for basic metadata (layer 3 and 4 protocol numbers), 5-tuple payload matching and the accept/drop actions; this also includes basechain hardware offload only. Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- net/netfilter/nf_tables_offload.c | 267 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 267 insertions(+) create mode 100644 net/netfilter/nf_tables_offload.c (limited to 'net/netfilter/nf_tables_offload.c') diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c new file mode 100644 index 000000000000..2c3302845f67 --- /dev/null +++ b/net/netfilter/nf_tables_offload.c @@ -0,0 +1,267 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include +#include +#include +#include +#include +#include +#include + +static struct nft_flow_rule *nft_flow_rule_alloc(int num_actions) +{ + struct nft_flow_rule *flow; + + flow = kzalloc(sizeof(struct nft_flow_rule), GFP_KERNEL); + if (!flow) + return NULL; + + flow->rule = flow_rule_alloc(num_actions); + if (!flow->rule) { + kfree(flow); + return NULL; + } + + flow->rule->match.dissector = &flow->match.dissector; + flow->rule->match.mask = &flow->match.mask; + flow->rule->match.key = &flow->match.key; + + return flow; +} + +struct nft_flow_rule *nft_flow_rule_create(const struct nft_rule *rule) +{ + struct nft_offload_ctx ctx = { + .dep = { + .type = NFT_OFFLOAD_DEP_UNSPEC, + }, + }; + struct nft_flow_rule *flow; + int num_actions = 0, err; + struct nft_expr *expr; + + expr = nft_expr_first(rule); + while (expr->ops && expr != nft_expr_last(rule)) { + if (expr->ops->offload_flags & NFT_OFFLOAD_F_ACTION) + num_actions++; + + expr = nft_expr_next(expr); + } + + flow = nft_flow_rule_alloc(num_actions); + if (!flow) + return ERR_PTR(-ENOMEM); + + expr = nft_expr_first(rule); + while (expr->ops && expr != nft_expr_last(rule)) { + if (!expr->ops->offload) { + err = -EOPNOTSUPP; + goto err_out; + } + err = expr->ops->offload(&ctx, flow, expr); + if (err < 0) + goto err_out; + + expr = nft_expr_next(expr); + } + flow->proto = ctx.dep.l3num; + + return flow; +err_out: + nft_flow_rule_destroy(flow); + + return ERR_PTR(err); +} + +void nft_flow_rule_destroy(struct nft_flow_rule *flow) +{ + kfree(flow->rule); + kfree(flow); +} + +void nft_offload_set_dependency(struct nft_offload_ctx *ctx, + enum nft_offload_dep_type type) +{ + ctx->dep.type = type; +} + +void nft_offload_update_dependency(struct nft_offload_ctx *ctx, + const void *data, u32 len) +{ + switch (ctx->dep.type) { + case NFT_OFFLOAD_DEP_NETWORK: + WARN_ON(len != sizeof(__u16)); + memcpy(&ctx->dep.l3num, data, sizeof(__u16)); + break; + case NFT_OFFLOAD_DEP_TRANSPORT: + WARN_ON(len != sizeof(__u8)); + memcpy(&ctx->dep.protonum, data, sizeof(__u8)); + break; + default: + break; + } + ctx->dep.type = NFT_OFFLOAD_DEP_UNSPEC; +} + +static void nft_flow_offload_common_init(struct flow_cls_common_offload *common, + __be16 proto, + struct netlink_ext_ack *extack) +{ + common->protocol = proto; + common->extack = extack; +} + +static int nft_setup_cb_call(struct nft_base_chain *basechain, + enum tc_setup_type type, void *type_data) +{ + struct flow_block_cb *block_cb; + int err; + + list_for_each_entry(block_cb, &basechain->cb_list, list) { + err = block_cb->cb(type, type_data, block_cb->cb_priv); + if (err < 0) + return err; + } + return 0; +} + +static int nft_flow_offload_rule(struct nft_trans *trans, + enum flow_cls_command command) +{ + struct nft_flow_rule *flow = nft_trans_flow_rule(trans); + struct nft_rule *rule = nft_trans_rule(trans); + struct flow_cls_offload cls_flow = {}; + struct nft_base_chain *basechain; + struct netlink_ext_ack extack; + __be16 proto = ETH_P_ALL; + + if (!nft_is_base_chain(trans->ctx.chain)) + return -EOPNOTSUPP; + + basechain = nft_base_chain(trans->ctx.chain); + + if (flow) + proto = flow->proto; + + nft_flow_offload_common_init(&cls_flow.common, proto, &extack); + cls_flow.command = command; + cls_flow.cookie = (unsigned long) rule; + if (flow) + cls_flow.rule = flow->rule; + + return nft_setup_cb_call(basechain, TC_SETUP_CLSFLOWER, &cls_flow); +} + +static int nft_flow_offload_bind(struct flow_block_offload *bo, + struct nft_base_chain *basechain) +{ + list_splice(&bo->cb_list, &basechain->cb_list); + return 0; +} + +static int nft_flow_offload_unbind(struct flow_block_offload *bo, + struct nft_base_chain *basechain) +{ + struct flow_block_cb *block_cb, *next; + + list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { + list_del(&block_cb->list); + flow_block_cb_free(block_cb); + } + + return 0; +} + +#define FLOW_SETUP_BLOCK TC_SETUP_BLOCK + +static int nft_flow_offload_chain(struct nft_trans *trans, + enum flow_block_command cmd) +{ + struct nft_chain *chain = trans->ctx.chain; + struct netlink_ext_ack extack = {}; + struct flow_block_offload bo = {}; + struct nft_base_chain *basechain; + struct net_device *dev; + int err; + + if (!nft_is_base_chain(chain)) + return -EOPNOTSUPP; + + basechain = nft_base_chain(chain); + dev = basechain->ops.dev; + if (!dev || !dev->netdev_ops->ndo_setup_tc) + return -EOPNOTSUPP; + + /* Only default policy to accept is supported for now. */ + if (cmd == FLOW_BLOCK_BIND && + nft_trans_chain_policy(trans) != -1 && + nft_trans_chain_policy(trans) != NF_ACCEPT) + return -EOPNOTSUPP; + + bo.command = cmd; + bo.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS; + bo.extack = &extack; + INIT_LIST_HEAD(&bo.cb_list); + + err = dev->netdev_ops->ndo_setup_tc(dev, FLOW_SETUP_BLOCK, &bo); + if (err < 0) + return err; + + switch (cmd) { + case FLOW_BLOCK_BIND: + err = nft_flow_offload_bind(&bo, basechain); + break; + case FLOW_BLOCK_UNBIND: + err = nft_flow_offload_unbind(&bo, basechain); + break; + } + + return err; +} + +int nft_flow_rule_offload_commit(struct net *net) +{ + struct nft_trans *trans; + int err = 0; + + list_for_each_entry(trans, &net->nft.commit_list, list) { + if (trans->ctx.family != NFPROTO_NETDEV) + continue; + + switch (trans->msg_type) { + case NFT_MSG_NEWCHAIN: + if (!(trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)) + continue; + + err = nft_flow_offload_chain(trans, FLOW_BLOCK_BIND); + break; + case NFT_MSG_DELCHAIN: + if (!(trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)) + continue; + + err = nft_flow_offload_chain(trans, FLOW_BLOCK_UNBIND); + break; + case NFT_MSG_NEWRULE: + if (!(trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)) + continue; + + if (trans->ctx.flags & NLM_F_REPLACE || + !(trans->ctx.flags & NLM_F_APPEND)) + return -EOPNOTSUPP; + + err = nft_flow_offload_rule(trans, FLOW_CLS_REPLACE); + nft_flow_rule_destroy(nft_trans_flow_rule(trans)); + break; + case NFT_MSG_DELRULE: + if (!(trans->ctx.chain->flags & NFT_CHAIN_HW_OFFLOAD)) + continue; + + err = nft_flow_offload_rule(trans, FLOW_CLS_DESTROY); + break; + } + + if (err) + return err; + } + + return err; +} -- cgit v1.2.3