Add support for source-specific IPv6 routes to BIRD core

This patch adds support for source-specific IPv6 routes to BIRD core.
This is based on Dean Luga's original patch, with the review comments
addressed. SADR support is added to network address parsing in confbase.Y
and to the kernel protocol on Linux.

Currently there is no way to mix source-specific and non-source-specific
routes (i.e., SADR tables cannot be connected to non-SADR tables).

Thanks to Toke Hoiland-Jorgensen for the original patch.
Minor changes by Ondrej Santiago Zajicek.

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/net.c b/lib/net.c
index 3e5d62e2..976ddbcc 100644
--- a/lib/net.c
+++ b/lib/net.c
@@ -14,6 +14,7 @@ const char * const net_label[] = {
   [NET_ROA6]	= "roa6",
   [NET_FLOW4]	= "flow4",
   [NET_FLOW6]	= "flow6",
+  [NET_IP6_SADR]= "ipv6-sadr",
   [NET_MPLS]	= "mpls",
 };
 
@@ -26,6 +27,7 @@ const u16 net_addr_length[] = {
   [NET_ROA6]	= sizeof(net_addr_roa6),
   [NET_FLOW4]	= 0,
   [NET_FLOW6]	= 0,
+  [NET_IP6_SADR]= sizeof(net_addr_ip6_sadr),
   [NET_MPLS]	= sizeof(net_addr_mpls),
 };
 
@@ -38,6 +40,7 @@ const u8 net_max_prefix_length[] = {
   [NET_ROA6]	= IP6_MAX_PREFIX_LENGTH,
   [NET_FLOW4]	= IP4_MAX_PREFIX_LENGTH,
   [NET_FLOW6]	= IP6_MAX_PREFIX_LENGTH,
+  [NET_IP6_SADR]= IP6_MAX_PREFIX_LENGTH,
   [NET_MPLS]	= 0,
 };
 
@@ -50,6 +53,7 @@ const u16 net_max_text_length[] = {
   [NET_ROA6]	= 60,	/* "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128-128 AS4294967295" */
   [NET_FLOW4]	= 0,	/* "flow4 { ... }" */
   [NET_FLOW6]	= 0,	/* "flow6 { ... }" */
+  [NET_IP6_SADR]= 92,	/* "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128 from ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128" */
   [NET_MPLS]	= 7,	/* "1048575" */
 };
 
@@ -102,6 +106,8 @@ net_format(const net_addr *N, char *buf, int buflen)
     return flow4_net_format(buf, buflen, &n->flow4);
   case NET_FLOW6:
     return flow6_net_format(buf, buflen, &n->flow6);
+  case NET_IP6_SADR:
+    return bsnprintf(buf, buflen, "%I6/%d from %I6/%d", n->ip6_sadr.dst_prefix, n->ip6_sadr.dst_pxlen, n->ip6_sadr.src_prefix, n->ip6_sadr.src_pxlen);
   case NET_MPLS:
     return bsnprintf(buf, buflen, "%u", n->mpls.label);
   }
@@ -124,6 +130,7 @@ net_pxmask(const net_addr *a)
   case NET_VPN6:
   case NET_ROA6:
   case NET_FLOW6:
+  case NET_IP6_SADR:
     return ipa_from_ip6(ip6_mkmask(net6_pxlen(a)));
 
   case NET_MPLS:
@@ -156,6 +163,8 @@ net_compare(const net_addr *a, const net_addr *b)
     return net_compare_flow4((const net_addr_flow4 *) a, (const net_addr_flow4 *) b);
   case NET_FLOW6:
     return net_compare_flow6((const net_addr_flow6 *) a, (const net_addr_flow6 *) b);
+  case NET_IP6_SADR:
+    return net_compare_ip6_sadr((const net_addr_ip6_sadr *) a, (const net_addr_ip6_sadr *) b);
   case NET_MPLS:
     return net_compare_mpls((const net_addr_mpls *) a, (const net_addr_mpls *) b);
   }
@@ -177,6 +186,7 @@ net_hash(const net_addr *n)
   case NET_ROA6: return NET_HASH(n, roa6);
   case NET_FLOW4: return NET_HASH(n, flow4);
   case NET_FLOW6: return NET_HASH(n, flow6);
+  case NET_IP6_SADR: return NET_HASH(n, ip6_sadr);
   case NET_MPLS: return NET_HASH(n, mpls);
   default: bug("invalid type");
   }
@@ -198,6 +208,7 @@ net_validate(const net_addr *n)
   case NET_ROA6: return NET_VALIDATE(n, roa6);
   case NET_FLOW4: return NET_VALIDATE(n, flow4);
   case NET_FLOW6: return NET_VALIDATE(n, flow6);
+  case NET_IP6_SADR: return NET_VALIDATE(n, ip6_sadr);
   case NET_MPLS: return NET_VALIDATE(n, mpls);
   default: return 0;
   }
@@ -222,6 +233,9 @@ net_normalize(net_addr *N)
   case NET_FLOW6:
     return net_normalize_ip6(&n->ip6);
 
+  case NET_IP6_SADR:
+    return net_normalize_ip6_sadr(&n->ip6_sadr);
+
   case NET_MPLS:
     return;
   }
@@ -246,6 +260,9 @@ net_classify(const net_addr *N)
   case NET_FLOW6:
     return ip6_zero(n->ip6.prefix) ? (IADDR_HOST | SCOPE_UNIVERSE) : ip6_classify(&n->ip6.prefix);
 
+  case NET_IP6_SADR:
+    return ip6_zero(n->ip6_sadr.dst_prefix) ? (IADDR_HOST | SCOPE_UNIVERSE) : ip6_classify(&n->ip6_sadr.dst_prefix);
+
   case NET_MPLS:
     return IADDR_HOST | SCOPE_UNIVERSE;
   }
@@ -274,6 +291,11 @@ ipa_in_netX(const ip_addr a, const net_addr *n)
     return ip6_zero(ip6_and(ip6_xor(ipa_to_ip6(a), net6_prefix(n)),
 			    ip6_mkmask(net6_pxlen(n))));
 
+  case NET_IP6_SADR:
+    if (ipa_is_ip4(a)) return 0;
+    return ip6_zero(ip6_and(ip6_xor(ipa_to_ip6(a), net6_prefix(n)),
+			    ip6_mkmask(net6_pxlen(n))));
+
   case NET_MPLS:
   default:
     return 0;
@@ -304,5 +326,6 @@ net_init(void)
   CHECK_NET(net_addr_roa6,	28);
   CHECK_NET(net_addr_flow4,	 8);
   CHECK_NET(net_addr_flow6,	20);
+  CHECK_NET(net_addr_ip6_sadr,	40);
   CHECK_NET(net_addr_mpls,	 8);
 }