[PATCH dpdk v2 15/16] net: add utilities for well known ipv6 address types

[Robin Jarry <rjarry@redhat.com>]

Add more utilities to work with IPv6 addresses. These functions will be
required in order to help building IPv6 routing applications.

Signed-off-by: Robin Jarry <rjarry@redhat.com>
---

Notes:
    v2:
    
    - added more multicast helpers
    - fixed all routers well known multicast addresses

 app/test/test_net_ipv6.c |  74 +++++++++++++++++++
 lib/net/rte_ip6.h        | 149 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 223 insertions(+)

diff --git a/app/test/test_net_ipv6.c b/app/test/test_net_ipv6.c
index c2b42d67285e..b087b5c60d73 100644
--- a/app/test/test_net_ipv6.c
+++ b/app/test/test_net_ipv6.c
@@ -93,26 +93,97 @@ static int
 test_ipv6_addr_kind(void)
 {
 	TEST_ASSERT(rte_ipv6_addr_is_unspec(&zero_addr), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_linklocal(&zero_addr), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_loopback(&zero_addr), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_mcast(&zero_addr), "");
 
 	struct rte_ipv6_addr ucast = {
 		"\x2a\x01\xcb\x00\x02\x54\x33\x00\x62\x39\xe1\xf4\x7a\x0b\x23\x71"
 	};
 	TEST_ASSERT(!rte_ipv6_addr_is_unspec(&ucast), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_linklocal(&ucast), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_loopback(&ucast), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_mcast(&ucast), "");
 
 	struct rte_ipv6_addr mcast = {
 		"\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"
 	};
 	TEST_ASSERT(!rte_ipv6_addr_is_unspec(&mcast), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_linklocal(&mcast), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_loopback(&mcast), "");
+	TEST_ASSERT(rte_ipv6_addr_is_mcast(&mcast), "");
 
 	struct rte_ipv6_addr lo = {
 		"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"
 	};
 	TEST_ASSERT(!rte_ipv6_addr_is_unspec(&lo), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_linklocal(&lo), "");
+	TEST_ASSERT(rte_ipv6_addr_is_loopback(&lo), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_mcast(&lo), "");
 
 	struct rte_ipv6_addr local = {
 		"\xfe\x80\x00\x00\x00\x00\x00\x00\x5a\x84\xc5\x2c\x6a\xef\x46\x39"
 	};
 	TEST_ASSERT(!rte_ipv6_addr_is_unspec(&local), "");
+	TEST_ASSERT(rte_ipv6_addr_is_linklocal(&local), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_loopback(&local), "");
+	TEST_ASSERT(!rte_ipv6_addr_is_mcast(&local), "");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_ipv6_llocal_from_ethernet(void)
+{
+	const struct rte_ether_addr local_mac = { "\x04\x7b\xcb\x5c\x08\x44" };
+	const struct rte_ipv6_addr local_ip = {
+		"\xfe\x80\x00\x00\x00\x00\x00\x00\x04\x7b\xcb\xff\xfe\x5c\x08\x44"
+	};
+	struct rte_ipv6_addr ip;
+
+	rte_ipv6_llocal_from_ethernet(&ip, &local_mac);
+	TEST_ASSERT(rte_ipv6_addr_eq(&ip, &local_ip), "");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_ipv6_solnode_from_addr(void)
+{
+	struct rte_ipv6_addr sol;
+
+	const struct rte_ipv6_addr llocal = {
+		"\xfe\x80\x00\x00\x00\x00\x00\x00\x04\x7b\xcb\xff\xfe\x5c\x08\x44"
+	};
+	const struct rte_ipv6_addr llocal_sol = {
+		"\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xff\x5c\x08\x44"
+	};
+	rte_ipv6_solnode_from_addr(&sol, &llocal);
+	TEST_ASSERT(rte_ipv6_addr_eq(&sol, &llocal_sol), "");
+
+	const struct rte_ipv6_addr ucast = {
+		"\x2a\x01\xcb\x00\x02\x54\x33\x00\x1b\x9f\x80\x71\x67\xcd\xbf\x20"
+	};
+	const struct rte_ipv6_addr ucast_sol = {
+		"\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xff\xcd\xbf\x20"
+	};
+	rte_ipv6_solnode_from_addr(&sol, &ucast);
+	TEST_ASSERT(rte_ipv6_addr_eq(&sol, &ucast_sol), "");
+
+	return TEST_SUCCESS;
+}
+
+static int
+test_ether_mcast_from_ipv6(void)
+{
+	const struct rte_ether_addr mcast_mac = { "\x33\x33\xd3\x00\x02\x01" };
+	const struct rte_ipv6_addr mcast_ip = {
+		"\xff\x02\x00\x00\x00\x00\x02\x01\x00\x00\x00\x00\xd3\x00\x02\x01"
+	};
+	struct rte_ether_addr mac;
+
+	rte_ether_mcast_from_ipv6(&mac, &mcast_ip);
+	TEST_ASSERT(rte_is_same_ether_addr(&mac, &mcast_mac), "");
 
 	return TEST_SUCCESS;
 }
@@ -123,6 +194,9 @@ test_net_ipv6(void)
 	TEST_ASSERT_SUCCESS(test_ipv6_addr_mask(), "");
 	TEST_ASSERT_SUCCESS(test_ipv6_addr_eq_prefix(), "");
 	TEST_ASSERT_SUCCESS(test_ipv6_addr_kind(), "");
+	TEST_ASSERT_SUCCESS(test_ipv6_llocal_from_ethernet(), "");
+	TEST_ASSERT_SUCCESS(test_ipv6_solnode_from_addr(), "");
+	TEST_ASSERT_SUCCESS(test_ether_mcast_from_ipv6(), "");
 	return TEST_SUCCESS;
 }
 
diff --git a/lib/net/rte_ip6.h b/lib/net/rte_ip6.h
index c139193e93f3..c552fa54c095 100644
--- a/lib/net/rte_ip6.h
+++ b/lib/net/rte_ip6.h
@@ -28,6 +28,7 @@
 #include <netinet/ip6.h>
 #endif
 
+#include <rte_ether.h>
 #include <rte_byteorder.h>
 #include <rte_mbuf.h>
 #include <rte_memcpy.h>
@@ -162,6 +163,154 @@ rte_ipv6_addr_is_unspec(const struct rte_ipv6_addr *ip)
 	return rte_ipv6_addr_eq(ip, &unspec);
 }
 
+/** Loopback address as defined in RFC 4291, section 2.7.1. */
+#define RTE_IPV6_ADDR_LOOPBACK RTE_IPV6_ADDR(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1)
+
+/**
+ * Check if an IPv6 address is the loopback address as defined in RFC 4291,
+ * section 2.5.3.
+ */
+static inline bool
+rte_ipv6_addr_is_loopback(const struct rte_ipv6_addr *ip)
+{
+	struct rte_ipv6_addr loopback = RTE_IPV6_ADDR_LOOPBACK;
+	return rte_ipv6_addr_eq(ip, &loopback);
+}
+
+/**
+ * Check if an IPv6 address is link-local as defined in RFC 4291, section 2.5.6.
+ */
+static inline bool
+rte_ipv6_addr_is_linklocal(const struct rte_ipv6_addr *ip)
+{
+	return ip->a[0] == 0xfe && (ip->a[1] & 0xc0) == 0x80;
+}
+
+/**
+ * Check if an IPv6 address is site-local as defined in RFC 4291, section 2.5.7.
+ */
+static inline bool
+rte_ipv6_addr_is_sitelocal(const struct rte_ipv6_addr *ip)
+{
+	return ip->a[0] == 0xfe && (ip->a[1] & 0xc0) == 0xc0;
+}
+
+/**
+ * Check if an IPv6 address is an IPv4-compatible address as defined in RFC 4291,
+ * section 2.5.5.1.
+ */
+static inline bool
+rte_ipv6_addr_is_v4compat(const struct rte_ipv6_addr *ip)
+{
+	const rte_be32_t *a32 = (const rte_be32_t *)ip;
+	return a32[0] == 0 && a32[1] == 0 && a32[2] == 0 && a32[3] != 0 && a32[3] != RTE_BE32(1);
+}
+
+/**
+ * Check if an IPv6 address is an IPv4-mapped address as defined in RFC 4291,
+ * section 2.5.5.2.
+ */
+static inline bool
+rte_ipv6_addr_is_v4mapped(const struct rte_ipv6_addr *ip)
+{
+	const rte_be32_t *a32 = (const rte_be32_t *)ip;
+	return a32[0] == 0 && a32[1] == 0 && a32[2] == RTE_BE32(0x0000ffff);
+}
+
+/**
+ * IPv6 multicast scope values as defined in RFC 4291, section 2.7.
+ */
+typedef enum {
+	RTE_IPV6_MC_SCOPE_RESERVED = 0x00,
+	RTE_IPV6_MC_SCOPE_IFACELOCAL = 0x01,
+	RTE_IPV6_MC_SCOPE_LINKLOCAL = 0x02,
+	RTE_IPV6_MC_SCOPE_SITELOCAL = 0x05,
+	RTE_IPV6_MC_SCOPE_ORGLOCAL = 0x08,
+	RTE_IPV6_MC_SCOPE_GLOBAL = 0x0e,
+} __rte_packed rte_ipv6_mc_scope_t;
+
+/**
+ * Extract the IPv6 multicast scope value as defined in RFC 4291, section 2.7.
+ */
+static inline rte_ipv6_mc_scope_t
+rte_ipv6_mc_scope(const struct rte_ipv6_addr *ip)
+{
+	return (rte_ipv6_mc_scope_t)(ip->a[1] & 0x0f);
+}
+
+/**
+ * Check if an IPv6 address is multicast as defined in RFC 4291, section 2.7.
+ */
+static inline bool
+rte_ipv6_addr_is_mcast(const struct rte_ipv6_addr *ip)
+{
+	return ip->a[0] == 0xff;
+}
+
+/** Well known multicast addresses as defined in RFC 4291, section 2.7.1. */
+#define RTE_IPV6_ADDR_ALLNODES_IFACE_LOCAL \
+	RTE_IPV6_ADDR(0xff, 0x01, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1)
+#define RTE_IPV6_ADDR_ALLNODES_LINK_LOCAL \
+	RTE_IPV6_ADDR(0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1)
+#define RTE_IPV6_ADDR_ALLROUTERS_IFACE_LOCAL \
+	RTE_IPV6_ADDR(0xff, 0x01, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2)
+#define RTE_IPV6_ADDR_ALLROUTERS_LINK_LOCAL \
+	RTE_IPV6_ADDR(0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2)
+#define RTE_IPV6_ADDR_ALLROUTERS_SITE_LOCAL \
+	RTE_IPV6_ADDR(0xff, 0x05, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2)
+
+/**
+ * Generate a link-local IPv6 address from an ethernet address as specified in
+ * RFC 2464, section 5.
+ */
+static inline void
+rte_ipv6_llocal_from_ethernet(struct rte_ipv6_addr *ip, const struct rte_ether_addr *mac)
+{
+	ip->a[0] = 0xfe;
+	ip->a[1] = 0x80;
+	memset(&ip->a[2], 0, 6);
+	ip->a[8] = mac->addr_bytes[0];
+	ip->a[9] = mac->addr_bytes[1];
+	ip->a[10] = mac->addr_bytes[2];
+	ip->a[11] = 0xff;
+	ip->a[12] = 0xfe;
+	ip->a[13] = mac->addr_bytes[3];
+	ip->a[14] = mac->addr_bytes[4];
+	ip->a[15] = mac->addr_bytes[5];
+}
+
+/**
+ * Convert a unicast or anycast IPv6 address to a solicited-node multicast
+ * address as defined in RFC 4291, section 2.7.1.
+ */
+static inline void
+rte_ipv6_solnode_from_addr(struct rte_ipv6_addr *sol, const struct rte_ipv6_addr *ip)
+{
+	sol->a[0] = 0xff;
+	sol->a[1] = 0x02;
+	memset(&sol->a[2], 0, 9);
+	sol->a[11] = 0x01;
+	sol->a[12] = 0xff;
+	sol->a[13] = ip->a[13];
+	sol->a[14] = ip->a[14];
+	sol->a[15] = ip->a[15];
+}
+
+/**
+ * Generate a multicast ethernet address from a multicast IPv6 address as defined
+ * in RFC 2464, section 7.
+ */
+static inline void
+rte_ether_mcast_from_ipv6(struct rte_ether_addr *mac, const struct rte_ipv6_addr *ip)
+{
+	mac->addr_bytes[0] = 0x33;
+	mac->addr_bytes[1] = 0x33;
+	mac->addr_bytes[2] = ip->a[12];
+	mac->addr_bytes[3] = ip->a[13];
+	mac->addr_bytes[4] = ip->a[14];
+	mac->addr_bytes[5] = ip->a[15];
+}
+
 /**
  * IPv6 Header
  */
-- 
2.46.1