net/sched: add tunnel option support to act_tunnel_key

Allow setting tunnel options using the act_tunnel_key action.

Options are expressed as class:type:data and multiple options
may be listed using a comma delimiter.

 # ip link add name geneve0 type geneve dstport 0 external
 # tc qdisc add dev eth0 ingress
 # tc filter add dev eth0 protocol ip parent ffff: \
     flower indev eth0 \
        ip_proto udp \
        action tunnel_key \
            set src_ip 10.0.99.192 \
            dst_ip 10.0.99.193 \
            dst_port 6081 \
            id 11 \
            geneve_opts 0102:80:00800022,0102:80:00800022 \
    action mirred egress redirect dev geneve0
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/tc_act/tc_tunnel_key.h

@@ -36,9 +36,35 @@ enum {
 	TCA_TUNNEL_KEY_PAD,
 	TCA_TUNNEL_KEY_ENC_DST_PORT,	/* be16 */
 	TCA_TUNNEL_KEY_NO_CSUM,		/* u8 */
+	TCA_TUNNEL_KEY_ENC_OPTS,	/* Nested TCA_TUNNEL_KEY_ENC_OPTS_
+					 * attributes
+					 */
 	__TCA_TUNNEL_KEY_MAX,
 };
 
 #define TCA_TUNNEL_KEY_MAX (__TCA_TUNNEL_KEY_MAX - 1)
 
+enum {
+	TCA_TUNNEL_KEY_ENC_OPTS_UNSPEC,
+	TCA_TUNNEL_KEY_ENC_OPTS_GENEVE,		/* Nested
+						 * TCA_TUNNEL_KEY_ENC_OPTS_
+						 * attributes
+						 */
+	__TCA_TUNNEL_KEY_ENC_OPTS_MAX,
+};
+
+#define TCA_TUNNEL_KEY_ENC_OPTS_MAX (__TCA_TUNNEL_KEY_ENC_OPTS_MAX - 1)
+
+enum {
+	TCA_TUNNEL_KEY_ENC_OPT_GENEVE_UNSPEC,
+	TCA_TUNNEL_KEY_ENC_OPT_GENEVE_CLASS,		/* be16 */
+	TCA_TUNNEL_KEY_ENC_OPT_GENEVE_TYPE,		/* u8 */
+	TCA_TUNNEL_KEY_ENC_OPT_GENEVE_DATA,		/* 4 to 128 bytes */
+
+	__TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX,
+};
+
+#define TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX \
+	(__TCA_TUNNEL_KEY_ENC_OPT_GENEVE_MAX - 1)
+
 #endif

net/sched/act_tunnel_key.c

@@ -13,6 +13,7 @@
 #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>
@@ -57,6 +58,135 @@ static int tunnel_key_act(struct sk_buff *skb, const struct tc_action *a,
 	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(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(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 },
@@ -66,6 +196,7 @@ static const struct nla_policy tunnel_key_policy[TCA_TUNNEL_KEY_MAX + 1] = {
 	[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 },
 };
 
 static int tunnel_key_init(struct net *net, struct nlattr *nla,
@@ -81,6 +212,7 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla,
 	struct tcf_tunnel_key *t;
 	bool exists = false;
 	__be16 dst_port = 0;
+	int opts_len = 0;
 	__be64 key_id;
 	__be16 flags;
 	int ret = 0;
@@ -128,6 +260,15 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla,
 		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;
+			}
+		}
+
 		if (tb[TCA_TUNNEL_KEY_ENC_IPV4_SRC] &&
 		    tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]) {
 			__be32 saddr;
@@ -138,7 +279,7 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla,
 
 			metadata = __ip_tun_set_dst(saddr, daddr, 0, 0,
 						    dst_port, flags,
-						    key_id, 0);
+						    key_id, opts_len);
 		} else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
 			   tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
 			struct in6_addr saddr;
@@ -162,6 +303,14 @@ static int tunnel_key_init(struct net *net, struct nlattr *nla,
 			goto err_out;
 		}
 
+		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 err_out;
+		}
+
 		metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX;
 		break;
 	default:
@@ -234,6 +383,61 @@ static void tunnel_key_release(struct tc_action *a)
 	}
 }
 
+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(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))
+			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;
+
+	if (!info->options_len)
+		return 0;
+
+	start = nla_nest_start(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)
+			return err;
+	} else {
+		return -EINVAL;
+	}
+
+	nla_nest_end(skb, start);
+	return 0;
+}
+
 static int tunnel_key_dump_addresses(struct sk_buff *skb,
 				     const struct ip_tunnel_info *info)
 {
@@ -284,8 +488,9 @@ static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
 		goto nla_put_failure;
 
 	if (params->tcft_action == TCA_TUNNEL_KEY_ACT_SET) {
-		struct ip_tunnel_key *key =
-			&params->tcft_enc_metadata->u.tun_info.key;
+		struct ip_tunnel_info *info =
+			&params->tcft_enc_metadata->u.tun_info;
+		struct ip_tunnel_key *key = &info->key;
 		__be32 key_id = tunnel_id_to_key32(key->tun_id);
 
 		if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
@@ -293,7 +498,8 @@ static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
 					      &params->tcft_enc_metadata->u.tun_info) ||
 		    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)))
+			       !(key->tun_flags & TUNNEL_CSUM)) ||
+		    tunnel_key_opts_dump(skb, info))
 			goto nla_put_failure;
 	}