lib, zebra: Add SR-TE policy infrastructure to zebra

For the sake of Segment Routing (SR) and Traffic Engineering (TE)
Policies there's a need for additional infrastructure within zebra.
The infrastructure in this PR is supposed to manage such policies
in terms of installing binding SIDs and LSPs. Also it is capable of
managing MPLS labels using the label manager, keeping track of
nexthops (for resolving labels) and notifying interested parties about
changes of a policy/LSP state. Further it enables a route map mechanism
for BGP and SR-TE colors such that learned BGP routes can be mapped
onto SR-TE Policies.

This PR does not introduce any usable features by now, it is just
infrastructure for other upcoming PRs which will introduce 'pathd',
a new SR-TE daemon.

Co-authored-by: Renato Westphal <renato@opensourcerouting.org>
Co-authored-by: GalaxyGorilla <sascha@netdef.org>
Signed-off-by: Sebastien Merle <sebastien@netdef.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/lib/stream.c b/lib/stream.c
index d3afebbf1..768114e69 100644
--- a/lib/stream.c
+++ b/lib/stream.c
@@ -586,6 +586,43 @@ uint32_t stream_get_ipv4(struct stream *s)
 	return l;
 }
 
+bool stream_get_ipaddr(struct stream *s, struct ipaddr *ip)
+{
+	uint16_t ipa_len;
+
+	STREAM_VERIFY_SANE(s);
+
+	/* Get address type. */
+	if (STREAM_READABLE(s) < sizeof(uint16_t)) {
+		STREAM_BOUND_WARN2(s, "get ipaddr");
+		return false;
+	}
+	ip->ipa_type = stream_getw(s);
+
+	/* Get address value. */
+	switch (ip->ipa_type) {
+	case IPADDR_V4:
+		ipa_len = IPV4_MAX_BYTELEN;
+		break;
+	case IPADDR_V6:
+		ipa_len = IPV6_MAX_BYTELEN;
+		break;
+	default:
+		flog_err(EC_LIB_DEVELOPMENT,
+			 "%s: unknown ip address-family: %u", __func__,
+			 ip->ipa_type);
+		return false;
+	}
+	if (STREAM_READABLE(s) < ipa_len) {
+		STREAM_BOUND_WARN2(s, "get ipaddr");
+		return false;
+	}
+	memcpy(&ip->ip, s->data + s->getp, ipa_len);
+	s->getp += ipa_len;
+
+	return true;
+}
+
 float stream_getf(struct stream *s)
 {
 	union {
@@ -852,6 +889,27 @@ int stream_put_in_addr(struct stream *s, const struct in_addr *addr)
 	return sizeof(uint32_t);
 }
 
+bool stream_put_ipaddr(struct stream *s, struct ipaddr *ip)
+{
+	stream_putw(s, ip->ipa_type);
+
+	switch (ip->ipa_type) {
+	case IPADDR_V4:
+		stream_put_in_addr(s, &ip->ipaddr_v4);
+		break;
+	case IPADDR_V6:
+		stream_write(s, (uint8_t *)&ip->ipaddr_v6, 16);
+		break;
+	default:
+		flog_err(EC_LIB_DEVELOPMENT,
+			 "%s: unknown ip address-family: %u", __func__,
+			 ip->ipa_type);
+		return false;
+	}
+
+	return true;
+}
+
 /* Put in_addr at location in the stream. */
 int stream_put_in_addr_at(struct stream *s, size_t putp,
 			  const struct in_addr *addr)