ila: allow configuration of identifier type

Allow identifier to be explicitly configured for a mapping.
This can either be one of the identifier types specified in the
ILA draft or a value of ILA_ATYPE_USE_FORMAT which means the
identifier type is inferred from the identifier type field.
If a value other than ILA_ATYPE_USE_FORMAT is set for a
mapping then it is assumed that the identifier type field is
not present in an identifier.

Signed-off-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/ila.h

@@ -17,6 +17,7 @@ enum {
 	ILA_ATTR_DIR,				/* u32 */
 	ILA_ATTR_PAD,
 	ILA_ATTR_CSUM_MODE,			/* u8 */
+	ILA_ATTR_IDENT_TYPE,			/* u8 */
 
 	__ILA_ATTR_MAX,
 };
@@ -44,4 +45,16 @@ enum {
 	ILA_CSUM_NEUTRAL_MAP_AUTO,
 };
 
+enum {
+	ILA_ATYPE_IID = 0,
+	ILA_ATYPE_LUID,
+	ILA_ATYPE_VIRT_V4,
+	ILA_ATYPE_VIRT_UNI_V6,
+	ILA_ATYPE_VIRT_MULTI_V6,
+	ILA_ATYPE_NONLOCAL_ADDR,
+	ILA_ATYPE_RSVD_1,
+	ILA_ATYPE_RSVD_2,
+
+	ILA_ATYPE_USE_FORMAT = 32, /* Get type from type field in identifier */
+};
 #endif /* _UAPI_LINUX_ILA_H */

net/ipv6/ila/ila.h

@@ -55,17 +55,6 @@ struct ila_identifier {
 	};
 };
 
-enum {
-	ILA_ATYPE_IID = 0,
-	ILA_ATYPE_LUID,
-	ILA_ATYPE_VIRT_V4,
-	ILA_ATYPE_VIRT_UNI_V6,
-	ILA_ATYPE_VIRT_MULTI_V6,
-	ILA_ATYPE_RSVD_1,
-	ILA_ATYPE_RSVD_2,
-	ILA_ATYPE_RSVD_3,
-};
-
 #define CSUM_NEUTRAL_FLAG	htonl(0x10000000)
 
 struct ila_addr {
@@ -93,6 +82,7 @@ struct ila_params {
 	struct ila_locator locator_match;
 	__wsum csum_diff;
 	u8 csum_mode;
+	u8 ident_type;
 };
 
 static inline __wsum compute_csum_diff8(const __be32 *from, const __be32 *to)

net/ipv6/ila/ila_lwt.c

@@ -114,6 +114,7 @@ drop:
 static const struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = {
 	[ILA_ATTR_LOCATOR] = { .type = NLA_U64, },
 	[ILA_ATTR_CSUM_MODE] = { .type = NLA_U8, },
+	[ILA_ATTR_IDENT_TYPE] = { .type = NLA_U8, },
 };
 
 static int ila_build_state(struct nlattr *nla,
@@ -127,19 +128,14 @@ static int ila_build_state(struct nlattr *nla,
 	struct lwtunnel_state *newts;
 	const struct fib6_config *cfg6 = cfg;
 	struct ila_addr *iaddr;
+	u8 ident_type = ILA_ATYPE_USE_FORMAT;
 	u8 csum_mode = ILA_CSUM_NO_ACTION;
+	u8 eff_ident_type;
 	int ret;
 
 	if (family != AF_INET6)
 		return -EINVAL;
 
-	if (cfg6->fc_dst_len < 8 * sizeof(struct ila_locator) + 3) {
-		/* Need to have full locator and at least type field
-		 * included in destination
-		 */
-		return -EINVAL;
-	}
-
 	ret = nla_parse_nested(tb, ILA_ATTR_MAX, nla, ila_nl_policy, extack);
 	if (ret < 0)
 		return ret;
@@ -149,6 +145,41 @@ static int ila_build_state(struct nlattr *nla,
 
 	iaddr = (struct ila_addr *)&cfg6->fc_dst;
 
+	if (tb[ILA_ATTR_IDENT_TYPE])
+		ident_type = nla_get_u8(tb[ILA_ATTR_IDENT_TYPE]);
+
+	if (ident_type == ILA_ATYPE_USE_FORMAT) {
+		/* Infer identifier type from type field in formatted
+		 * identifier.
+		 */
+
+		if (cfg6->fc_dst_len < 8 * sizeof(struct ila_locator) + 3) {
+			/* Need to have full locator and at least type field
+			 * included in destination
+			 */
+			return -EINVAL;
+		}
+
+		eff_ident_type = iaddr->ident.type;
+	} else {
+		eff_ident_type = ident_type;
+	}
+
+	switch (eff_ident_type) {
+	case ILA_ATYPE_IID:
+		/* Don't allow ILA for IID type */
+		return -EINVAL;
+	case ILA_ATYPE_LUID:
+		break;
+	case ILA_ATYPE_VIRT_V4:
+	case ILA_ATYPE_VIRT_UNI_V6:
+	case ILA_ATYPE_VIRT_MULTI_V6:
+	case ILA_ATYPE_NONLOCAL_ADDR:
+		/* These ILA formats are not supported yet. */
+	default:
+		return -EINVAL;
+	}
+
 	if (tb[ILA_ATTR_CSUM_MODE])
 		csum_mode = nla_get_u8(tb[ILA_ATTR_CSUM_MODE]);
 
@@ -174,6 +205,7 @@ static int ila_build_state(struct nlattr *nla,
 	p = ila_params_lwtunnel(newts);
 
 	p->csum_mode = csum_mode;
+	p->ident_type = ident_type;
 	p->locator.v64 = (__force __be64)nla_get_u64(tb[ILA_ATTR_LOCATOR]);
 
 	/* Precompute checksum difference for translation since we
@@ -208,9 +240,13 @@ static int ila_fill_encap_info(struct sk_buff *skb,
 	if (nla_put_u64_64bit(skb, ILA_ATTR_LOCATOR, (__force u64)p->locator.v64,
 			      ILA_ATTR_PAD))
 		goto nla_put_failure;
+
 	if (nla_put_u8(skb, ILA_ATTR_CSUM_MODE, (__force u8)p->csum_mode))
 		goto nla_put_failure;
 
+	if (nla_put_u8(skb, ILA_ATTR_IDENT_TYPE, (__force u8)p->ident_type))
+		goto nla_put_failure;
+
 	return 0;
 
 nla_put_failure:
@@ -221,6 +257,7 @@ static int ila_encap_nlsize(struct lwtunnel_state *lwtstate)
 {
 	return nla_total_size_64bit(sizeof(u64)) + /* ILA_ATTR_LOCATOR */
 	       nla_total_size(sizeof(u8)) +        /* ILA_ATTR_CSUM_MODE */
+	       nla_total_size(sizeof(u8)) +        /* ILA_ATTR_IDENT_TYPE */
 	       0;
 }
 

net/ipv6/ila/ila_xlat.c

@@ -121,6 +121,7 @@ static const struct nla_policy ila_nl_policy[ILA_ATTR_MAX + 1] = {
 	[ILA_ATTR_LOCATOR_MATCH] = { .type = NLA_U64, },
 	[ILA_ATTR_IFINDEX] = { .type = NLA_U32, },
 	[ILA_ATTR_CSUM_MODE] = { .type = NLA_U8, },
+	[ILA_ATTR_IDENT_TYPE] = { .type = NLA_U8, },
 };
 
 static int parse_nl_config(struct genl_info *info,
@@ -141,6 +142,12 @@ static int parse_nl_config(struct genl_info *info,
 	else
 		xp->ip.csum_mode = ILA_CSUM_NO_ACTION;
 
+	if (info->attrs[ILA_ATTR_IDENT_TYPE])
+		xp->ip.ident_type = nla_get_u8(
+				info->attrs[ILA_ATTR_IDENT_TYPE]);
+	else
+		xp->ip.ident_type = ILA_ATYPE_USE_FORMAT;
+
 	if (info->attrs[ILA_ATTR_IFINDEX])
 		xp->ifindex = nla_get_s32(info->attrs[ILA_ATTR_IFINDEX]);
 
@@ -398,7 +405,8 @@ static int ila_fill_info(struct ila_map *ila, struct sk_buff *msg)
 			      (__force u64)ila->xp.ip.locator_match.v64,
 			      ILA_ATTR_PAD) ||
 	    nla_put_s32(msg, ILA_ATTR_IFINDEX, ila->xp.ifindex) ||
-	    nla_put_u8(msg, ILA_ATTR_CSUM_MODE, ila->xp.ip.csum_mode))
+	    nla_put_u8(msg, ILA_ATTR_CSUM_MODE, ila->xp.ip.csum_mode) ||
+	    nla_put_u8(msg, ILA_ATTR_IDENT_TYPE, ila->xp.ip.ident_type))
 		return -1;
 
 	return 0;
@@ -619,10 +627,10 @@ static int ila_xlat_addr(struct sk_buff *skb, bool sir2ila)
 
 	/* Assumes skb contains a valid IPv6 header that is pulled */
 
-	if (!ila_addr_is_ila(iaddr)) {
-		/* Type indicates this is not an ILA address */
-		return 0;
-	}
+	/* No check here that ILA type in the mapping matches what is in the
+	 * address. We assume that whatever sender gaves us can be translated.
+	 * The checksum mode however is relevant.
+	 */
 
 	rcu_read_lock();