[PATCH nf-next,v3 1/3] netfilter: nft_payload: fix C-VLAN offload support

[PATCH nf-next,v3 1/3] netfilter: nft_payload: fix C-VLAN offload support

[Pablo Neira Ayuso]

- add another struct flow_dissector_key_vlan for C-VLAN
- update layer 3 dependency to allow to match on IPv4/IPv6

Fixes: 89d8fd44abfb ("netfilter: nft_payload: add C-VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
v3: no changes

 include/net/netfilter/nf_tables_offload.h | 1 +
 net/netfilter/nft_payload.c               | 5 +++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index 1d34fe154fe0..b4d080061399 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -45,6 +45,7 @@ struct nft_flow_key {
 	struct flow_dissector_key_ports			tp;
 	struct flow_dissector_key_ip			ip;
 	struct flow_dissector_key_vlan			vlan;
+	struct flow_dissector_key_vlan			cvlan;
 	struct flow_dissector_key_eth_addrs		eth_addrs;
 	struct flow_dissector_key_meta			meta;
 } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index cb1c8c231880..a990f37e0a60 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -241,7 +241,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
+		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 				  vlan_tci, sizeof(__be16), reg);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
@@ -249,8 +249,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
+		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
 				  vlan_tpid, sizeof(__be16), reg);
+		nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
 		break;
 	default:
 		return -EOPNOTSUPP;
-- 
2.30.2

[PATCH nf-next,v3 2/3] netfilter: nftables_offload: VLAN id needs host byteorder in flow dissector

[Pablo Neira Ayuso]

The flow dissector representation expects the VLAN id in host byteorder.
Add the NFT_OFFLOAD_F_NETWORK2HOST flag to swap the bytes from nft_cmp.

Fixes: a82055af5959 ("netfilter: nft_payload: add VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reported-by: kernel test robot <lkp@intel.com>
---
v3: fix sparse warnings.

 include/net/netfilter/nf_tables_offload.h | 11 +++++-
 net/netfilter/nft_cmp.c                   | 41 +++++++++++++++++++++--
 net/netfilter/nft_payload.c               | 10 +++---
 3 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index b4d080061399..434a6158852f 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -4,11 +4,16 @@
 #include <net/flow_offload.h>
 #include <net/netfilter/nf_tables.h>
 
+enum nft_offload_reg_flags {
+	NFT_OFFLOAD_F_NETWORK2HOST	= (1 << 0),
+};
+
 struct nft_offload_reg {
 	u32		key;
 	u32		len;
 	u32		base_offset;
 	u32		offset;
+	u32		flags;
 	struct nft_data data;
 	struct nft_data	mask;
 };
@@ -72,13 +77,17 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net, const struct nft_rul
 void nft_flow_rule_destroy(struct nft_flow_rule *flow);
 int nft_flow_rule_offload_commit(struct net *net);
 
-#define NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg)		\
+#define NFT_OFFLOAD_MATCH_FLAGS(__key, __base, __field, __len, __reg, __flags)	\
 	(__reg)->base_offset	=					\
 		offsetof(struct nft_flow_key, __base);			\
 	(__reg)->offset		=					\
 		offsetof(struct nft_flow_key, __base.__field);		\
 	(__reg)->len		= __len;				\
 	(__reg)->key		= __key;				\
+	(__reg)->flags		= __flags;
+
+#define NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg)		\
+	NFT_OFFLOAD_MATCH_FLAGS(__key, __base, __field, __len, __reg, 0)
 
 #define NFT_OFFLOAD_MATCH_EXACT(__key, __base, __field, __len, __reg)	\
 	NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg)		\
diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c
index eb6a43a180bb..e78de1fb547a 100644
--- a/net/netfilter/nft_cmp.c
+++ b/net/netfilter/nft_cmp.c
@@ -114,19 +114,56 @@ static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr)
 	return -1;
 }
 
+union nft_cmp_offload_data {
+	u16	val16;
+	u32	val32;
+	u64	val64;
+};
+
+static void nft_payload_n2h(union nft_cmp_offload_data *data,
+			    const u8 *val, u32 len)
+{
+	switch (len) {
+	case 2:
+		data->val16 = ntohs(*((__be16 *)val));
+		break;
+	case 4:
+		data->val32 = ntohl(*((__be32 *)val));
+		break;
+	case 8:
+		data->val64 = be64_to_cpu(*((__be64 *)val));
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		break;
+	}
+}
+
 static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
 			     struct nft_flow_rule *flow,
 			     const struct nft_cmp_expr *priv)
 {
 	struct nft_offload_reg *reg = &ctx->regs[priv->sreg];
+	union nft_cmp_offload_data _data, _datamask;
 	u8 *mask = (u8 *)&flow->match.mask;
 	u8 *key = (u8 *)&flow->match.key;
+	u8 *data, *datamask;
 
 	if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
 		return -EOPNOTSUPP;
 
-	memcpy(key + reg->offset, &priv->data, reg->len);
-	memcpy(mask + reg->offset, &reg->mask, reg->len);
+	if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) {
+		nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len);
+		nft_payload_n2h(&_datamask, (u8 *)&reg->mask, reg->len);
+		data = (u8 *)&_data;
+		datamask = (u8 *)&_datamask;
+	} else {
+		data = (u8 *)&priv->data;
+		datamask = (u8 *)&reg->mask;
+	}
+
+	memcpy(key + reg->offset, data, reg->len);
+	memcpy(mask + reg->offset, datamask, reg->len);
 
 	flow->match.dissector.used_keys |= BIT(reg->key);
 	flow->match.dissector.offset[reg->key] = reg->base_offset;
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index a990f37e0a60..501c5b24cc39 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -226,8 +226,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
-				  vlan_tci, sizeof(__be16), reg);
+		NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_VLAN, vlan,
+					vlan_tci, sizeof(__be16), reg,
+					NFT_OFFLOAD_F_NETWORK2HOST);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
@@ -241,8 +242,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
 		if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
 			return -EOPNOTSUPP;
 
-		NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
-				  vlan_tci, sizeof(__be16), reg);
+		NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
+					vlan_tci, sizeof(__be16), reg,
+					NFT_OFFLOAD_F_NETWORK2HOST);
 		break;
 	case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
 							sizeof(struct vlan_hdr):
-- 
2.30.2

[PATCH nf-next,v3 3/3] netfilter: nftables_offload: special ethertype handling for VLAN

[Pablo Neira Ayuso]

The nftables offload parser sets FLOW_DISSECTOR_KEY_BASIC .n_proto to the
ethertype field in the ethertype frame. However:

- FLOW_DISSECTOR_KEY_BASIC .n_proto field always stores either IPv4 or IPv6
  ethertypes.
- FLOW_DISSECTOR_KEY_VLAN .vlan_tpid stores either the 802.1q and 802.1ad
  ethertypes. Same as for FLOW_DISSECTOR_KEY_CVLAN.

This function adjusts the flow dissector to handle two scenarios:

1) FLOW_DISSECTOR_KEY_VLAN .vlan_tpid is set to 802.1q or 802.1ad.
   Then, transfer:
   - the .n_proto field to FLOW_DISSECTOR_KEY_VLAN .tpid.
   - the original FLOW_DISSECTOR_KEY_VLAN .tpid to the
     FLOW_DISSECTOR_KEY_CVLAN .tpid
   - the original FLOW_DISSECTOR_KEY_CVLAN .tpid to the .n_proto field.

2) .n_proto is set to 802.1q or 802.1ad. Then, transfer:
   - the .n_proto field to FLOW_DISSECTOR_KEY_VLAN .tpid.
   - the original FLOW_DISSECTOR_KEY_VLAN .tpid to the .n_proto field.

Fixes: a82055af5959 ("netfilter: nft_payload: add VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
v3: no changes.

 net/netfilter/nf_tables_offload.c | 45 +++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index 43b56eff3b04..0ae2fbf3d97b 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -47,6 +47,49 @@ void nft_flow_rule_set_addr_type(struct nft_flow_rule *flow,
 		offsetof(struct nft_flow_key, control);
 }
 
+struct nft_offload_ethertype {
+	__be16 value;
+	__be16 mask;
+};
+
+static void nft_flow_rule_transfer_vlan(struct nft_offload_ctx *ctx,
+					struct nft_flow_rule *flow)
+{
+	struct nft_flow_match *match = &flow->match;
+	struct nft_offload_ethertype ethertype;
+
+	if (match->key.basic.n_proto != htons(ETH_P_8021Q) &&
+	    match->key.basic.n_proto != htons(ETH_P_8021AD))
+		return;
+
+	ethertype.value = match->key.basic.n_proto;
+	ethertype.mask = match->mask.basic.n_proto;
+
+	if (match->key.vlan.vlan_tpid == htons(ETH_P_8021Q) ||
+	    match->key.vlan.vlan_tpid == htons(ETH_P_8021AD)) {
+		match->key.basic.n_proto = match->key.cvlan.vlan_tpid;
+		match->mask.basic.n_proto = match->mask.cvlan.vlan_tpid;
+		match->key.cvlan.vlan_tpid = match->key.vlan.vlan_tpid;
+		match->mask.cvlan.vlan_tpid = match->mask.vlan.vlan_tpid;
+		match->key.vlan.vlan_tpid = ethertype.value;
+		match->mask.vlan.vlan_tpid = ethertype.mask;
+		match->dissector.offset[FLOW_DISSECTOR_KEY_VLAN] =
+			offsetof(struct nft_flow_key, vlan);
+		match->dissector.offset[FLOW_DISSECTOR_KEY_CVLAN] =
+			offsetof(struct nft_flow_key, cvlan);
+		match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_VLAN) |
+					      BIT(FLOW_DISSECTOR_KEY_CVLAN);
+	} else {
+		match->key.basic.n_proto = match->key.vlan.vlan_tpid;
+		match->mask.basic.n_proto = match->mask.vlan.vlan_tpid;
+		match->key.vlan.vlan_tpid = ethertype.value;
+		match->mask.vlan.vlan_tpid = ethertype.mask;
+		match->dissector.offset[FLOW_DISSECTOR_KEY_VLAN] =
+			offsetof(struct nft_flow_key, vlan);
+		match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_VLAN);
+	}
+}
+
 struct nft_flow_rule *nft_flow_rule_create(struct net *net,
 					   const struct nft_rule *rule)
 {
@@ -91,6 +134,8 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net,
 
 		expr = nft_expr_next(expr);
 	}
+	nft_flow_rule_transfer_vlan(ctx, flow);
+
 	flow->proto = ctx->dep.l3num;
 	kfree(ctx);
 
-- 
2.30.2