Merge pull request #14089 from dmytroshytyi-6WIND/srv6_multiple_segs_sids

 bgpd,doc,lib,sharpd,staticd,yang,zebra: SRv6 multiple segs SIDs

5 files changed, 145 insertions, 41 deletions

diff --git a/lib/nexthop.c b/lib/nexthop.c
index 4f92ef9c8b..8df57e36a2 100644
--- a/lib/nexthop.c
+++ b/lib/nexthop.c
@@ -56,6 +56,7 @@ static int _nexthop_srv6_cmp(const struct nexthop *nh1,
 			     const struct nexthop *nh2)
 {
 	int ret = 0;
+	int i = 0;
 
 	if (!nh1->nh_srv6 && !nh2->nh_srv6)
 		return 0;
@@ -78,9 +79,26 @@ static int _nexthop_srv6_cmp(const struct nexthop *nh1,
 	if (ret != 0)
 		return ret;
 
-	ret = memcmp(&nh1->nh_srv6->seg6_segs,
-		     &nh2->nh_srv6->seg6_segs,
-		     sizeof(struct in6_addr));
+	if (!nh1->nh_srv6->seg6_segs && !nh2->nh_srv6->seg6_segs)
+		return 0;
+
+	if (!nh1->nh_srv6->seg6_segs && nh2->nh_srv6->seg6_segs)
+		return -1;
+
+	if (nh1->nh_srv6->seg6_segs && !nh2->nh_srv6->seg6_segs)
+		return 1;
+
+	if (nh1->nh_srv6->seg6_segs->num_segs !=
+	    nh2->nh_srv6->seg6_segs->num_segs)
+		return -1;
+
+	for (i = 0; i < nh1->nh_srv6->seg6_segs->num_segs; i++) {
+		ret = memcmp(&nh1->nh_srv6->seg6_segs->seg[i],
+			     &nh2->nh_srv6->seg6_segs->seg[i],
+			     sizeof(struct in6_addr));
+		if (ret != 0)
+			break;
+	}
 
 	return ret;
 }
@@ -362,7 +380,7 @@ struct nexthop *nexthop_new(void)
 	 * The linux kernel does some weird stuff with adding +1 to
 	 * all nexthop weights it gets over netlink.
 	 * To handle this, just default everything to 1 right from
-	 * from the beginning so we don't have to special case
+	 * the beginning so we don't have to special case
 	 * default weights in the linux netlink code.
 	 *
 	 * 1 should be a valid on all platforms anyway.
@@ -568,15 +586,25 @@ void nexthop_del_srv6_seg6local(struct nexthop *nexthop)
 	if (!nexthop->nh_srv6)
 		return;
 
+	if (nexthop->nh_srv6->seg6local_action == ZEBRA_SEG6_LOCAL_ACTION_UNSPEC)
+		return;
+
 	nexthop->nh_srv6->seg6local_action = ZEBRA_SEG6_LOCAL_ACTION_UNSPEC;
 
-	if (sid_zero(&nexthop->nh_srv6->seg6_segs))
+	if (nexthop->nh_srv6->seg6_segs &&
+	    (nexthop->nh_srv6->seg6_segs->num_segs == 0 ||
+	     sid_zero(nexthop->nh_srv6->seg6_segs)))
+		XFREE(MTYPE_NH_SRV6, nexthop->nh_srv6->seg6_segs);
+
+	if (nexthop->nh_srv6->seg6_segs == NULL)
 		XFREE(MTYPE_NH_SRV6, nexthop->nh_srv6);
 }
 
-void nexthop_add_srv6_seg6(struct nexthop *nexthop,
-			   const struct in6_addr *segs)
+void nexthop_add_srv6_seg6(struct nexthop *nexthop, const struct in6_addr *segs,
+			   int num_segs)
 {
+	int i;
+
 	if (!segs)
 		return;
 
@@ -584,7 +612,22 @@ void nexthop_add_srv6_seg6(struct nexthop *nexthop,
 		nexthop->nh_srv6 = XCALLOC(MTYPE_NH_SRV6,
 					   sizeof(struct nexthop_srv6));
 
-	nexthop->nh_srv6->seg6_segs = *segs;
+	/* Enforce limit on srv6 seg stack size */
+	if (num_segs > SRV6_MAX_SIDS)
+		num_segs = SRV6_MAX_SIDS;
+
+	if (!nexthop->nh_srv6->seg6_segs) {
+		nexthop->nh_srv6->seg6_segs =
+			XCALLOC(MTYPE_NH_SRV6,
+				sizeof(struct seg6_seg_stack) +
+					num_segs * sizeof(struct in6_addr));
+	}
+
+	nexthop->nh_srv6->seg6_segs->num_segs = num_segs;
+
+	for (i = 0; i < num_segs; i++)
+		memcpy(&nexthop->nh_srv6->seg6_segs->seg[i], &segs[i],
+		       sizeof(struct in6_addr));
 }
 
 void nexthop_del_srv6_seg6(struct nexthop *nexthop)
@@ -592,12 +635,14 @@ void nexthop_del_srv6_seg6(struct nexthop *nexthop)
 	if (!nexthop->nh_srv6)
 		return;
 
-	memset(&nexthop->nh_srv6->seg6_segs, 0,
-	       sizeof(nexthop->nh_srv6->seg6_segs));
-
-	if (nexthop->nh_srv6->seg6local_action ==
-	    ZEBRA_SEG6_LOCAL_ACTION_UNSPEC)
-		XFREE(MTYPE_NH_SRV6, nexthop->nh_srv6);
+	if (nexthop->nh_srv6->seg6local_action == ZEBRA_SEG6_LOCAL_ACTION_UNSPEC &&
+			nexthop->nh_srv6->seg6_segs) {
+		memset(nexthop->nh_srv6->seg6_segs->seg, 0,
+		       sizeof(struct in6_addr) *
+			       nexthop->nh_srv6->seg6_segs->num_segs);
+		XFREE(MTYPE_NH_SRV6, nexthop->nh_srv6->seg6_segs);
+	}
+	XFREE(MTYPE_NH_SRV6, nexthop->nh_srv6);
 }
 
 const char *nexthop2str(const struct nexthop *nexthop, char *str, int size)
@@ -743,11 +788,32 @@ uint32_t nexthop_hash_quick(const struct nexthop *nexthop)
 	}
 
 	if (nexthop->nh_srv6) {
-		key = jhash_1word(nexthop->nh_srv6->seg6local_action, key);
-		key = jhash(&nexthop->nh_srv6->seg6local_ctx,
-			    sizeof(nexthop->nh_srv6->seg6local_ctx), key);
-		key = jhash(&nexthop->nh_srv6->seg6_segs,
-			    sizeof(nexthop->nh_srv6->seg6_segs), key);
+		int segs_num = 0;
+		int i = 0;
+
+		if (nexthop->nh_srv6->seg6local_action !=
+		    ZEBRA_SEG6_LOCAL_ACTION_UNSPEC) {
+			key = jhash_1word(nexthop->nh_srv6->seg6local_action,
+					  key);
+			key = jhash(&nexthop->nh_srv6->seg6local_ctx,
+				    sizeof(nexthop->nh_srv6->seg6local_ctx),
+				    key);
+			if (nexthop->nh_srv6->seg6_segs)
+				key = jhash(&nexthop->nh_srv6->seg6_segs->seg[0],
+					    sizeof(struct in6_addr), key);
+		} else {
+			if (nexthop->nh_srv6->seg6_segs) {
+				segs_num = nexthop->nh_srv6->seg6_segs->num_segs;
+				while (segs_num >= 1) {
+					key = jhash(&nexthop->nh_srv6->seg6_segs
+							    ->seg[i],
+						    sizeof(struct in6_addr),
+						    key);
+					segs_num -= 1;
+					i += 1;
+				}
+			}
+		}
 	}
 
 	return key;
@@ -810,9 +876,13 @@ void nexthop_copy_no_recurse(struct nexthop *copy,
 			nexthop_add_srv6_seg6local(copy,
 				nexthop->nh_srv6->seg6local_action,
 				&nexthop->nh_srv6->seg6local_ctx);
-		if (!sid_zero(&nexthop->nh_srv6->seg6_segs))
+		if (nexthop->nh_srv6->seg6_segs &&
+		    nexthop->nh_srv6->seg6_segs->num_segs &&
+		    !sid_zero(nexthop->nh_srv6->seg6_segs))
 			nexthop_add_srv6_seg6(copy,
-				&nexthop->nh_srv6->seg6_segs);
+					      &nexthop->nh_srv6->seg6_segs->seg[0],
+					      nexthop->nh_srv6->seg6_segs
+						      ->num_segs);
 	}
 }
 
diff --git a/lib/nexthop.h b/lib/nexthop.h
index 2be89f8240..bed6447d49 100644
--- a/lib/nexthop.h
+++ b/lib/nexthop.h
@@ -157,8 +157,8 @@ void nexthop_del_labels(struct nexthop *);
 void nexthop_add_srv6_seg6local(struct nexthop *nexthop, uint32_t action,
 				const struct seg6local_context *ctx);
 void nexthop_del_srv6_seg6local(struct nexthop *nexthop);
-void nexthop_add_srv6_seg6(struct nexthop *nexthop,
-			   const struct in6_addr *segs);
+void nexthop_add_srv6_seg6(struct nexthop *nexthop, const struct in6_addr *seg,
+			   int num_segs);
 void nexthop_del_srv6_seg6(struct nexthop *nexthop);
 
 /*
diff --git a/lib/srv6.h b/lib/srv6.h
index 7c8c6b4a65..fb34f861c8 100644
--- a/lib/srv6.h
+++ b/lib/srv6.h
@@ -14,8 +14,11 @@
 #include <arpa/inet.h>
 #include <netinet/in.h>
 
-#define SRV6_MAX_SIDS 16
+#define SRV6_MAX_SIDS	  16
+#define SRV6_MAX_SEGS	  8
 #define SRV6_LOCNAME_SIZE 256
+#define SRH_BASE_HEADER_LENGTH 8
+#define SRH_SEGMENT_LENGTH     16
 
 #ifdef __cplusplus
 extern "C" {
@@ -74,6 +77,8 @@ enum seg6local_flavor_op {
 	ZEBRA_SEG6_LOCAL_FLV_OP_NEXT_CSID    = 4,
 };
 
+#define SRV6_SEG_STRLEN 1024
+
 struct seg6_segs {
 	size_t num_segs;
 	struct in6_addr segs[256];
@@ -89,6 +94,11 @@ struct seg6local_flavors_info {
 	uint8_t lcnode_func_len;
 };
 
+struct seg6_seg_stack {
+	uint8_t num_segs;
+	struct in6_addr seg[0]; /* 1 or more segs */
+};
+
 struct seg6local_context {
 	struct in_addr nh4;
 	struct in6_addr nh6;
@@ -170,7 +180,7 @@ struct nexthop_srv6 {
 	struct seg6local_context seg6local_ctx;
 
 	/* SRv6 Headend-behaviour */
-	struct in6_addr seg6_segs;
+	struct seg6_seg_stack *seg6_segs;
 };
 
 static inline const char *seg6_mode2str(enum seg6_mode_t mode)
@@ -206,12 +216,21 @@ static inline bool sid_diff(
 	return !sid_same(a, b);
 }
 
-static inline bool sid_zero(
-		const struct in6_addr *a)
+
+static inline bool sid_zero(const struct seg6_seg_stack *a)
+{
+	struct in6_addr zero = {};
+
+	assert(a);
+
+	return sid_same(&a->seg[0], &zero);
+}
+
+static inline bool sid_zero_ipv6(const struct in6_addr *a)
 {
 	struct in6_addr zero = {};
 
-	return sid_same(a, &zero);
+	return sid_same(&a[0], &zero);
 }
 
 static inline void *sid_copy(struct in6_addr *dst,
diff --git a/lib/zclient.c b/lib/zclient.c
index 68a3429822..f8f9cf7aba 100644
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -1061,10 +1061,11 @@ int zapi_nexthop_encode(struct stream *s, const struct zapi_nexthop *api_nh,
 			     sizeof(struct seg6local_context));
 	}
 
-	if (CHECK_FLAG(nh_flags, ZAPI_NEXTHOP_FLAG_SEG6))
-		stream_write(s, &api_nh->seg6_segs,
-			     sizeof(struct in6_addr));
-
+	if (CHECK_FLAG(nh_flags, ZAPI_NEXTHOP_FLAG_SEG6)) {
+		stream_putc(s, api_nh->seg_num);
+		stream_put(s, &api_nh->seg6_segs[0],
+			   api_nh->seg_num * sizeof(struct in6_addr));
+	}
 done:
 	return ret;
 }
@@ -1430,9 +1431,18 @@ int zapi_nexthop_decode(struct stream *s, struct zapi_nexthop *api_nh,
 			   sizeof(struct seg6local_context));
 	}
 
-	if (CHECK_FLAG(api_nh->flags, ZAPI_NEXTHOP_FLAG_SEG6))
-		STREAM_GET(&api_nh->seg6_segs, s,
-			   sizeof(struct in6_addr));
+	if (CHECK_FLAG(api_nh->flags, ZAPI_NEXTHOP_FLAG_SEG6)) {
+		STREAM_GETC(s, api_nh->seg_num);
+		if (api_nh->seg_num > SRV6_MAX_SIDS) {
+			flog_err(EC_LIB_ZAPI_ENCODE,
+				 "%s: invalid number of SRv6 Segs (%u)",
+				 __func__, api_nh->seg_num);
+			return -1;
+		}
+
+		STREAM_GET(&api_nh->seg6_segs[0], s,
+			   api_nh->seg_num * sizeof(struct in6_addr));
+	}
 
 	/* Success */
 	ret = 0;
@@ -2132,8 +2142,8 @@ struct nexthop *nexthop_from_zapi_nexthop(const struct zapi_nexthop *znh)
 		nexthop_add_srv6_seg6local(n, znh->seg6local_action,
 					   &znh->seg6local_ctx);
 
-	if (!sid_zero(&znh->seg6_segs))
-		nexthop_add_srv6_seg6(n, &znh->seg6_segs);
+	if (znh->seg_num && !sid_zero_ipv6(znh->seg6_segs))
+		nexthop_add_srv6_seg6(n, &znh->seg6_segs[0], znh->seg_num);
 
 	return n;
 }
@@ -2193,10 +2203,14 @@ int zapi_nexthop_from_nexthop(struct zapi_nexthop *znh,
 			       sizeof(struct seg6local_context));
 		}
 
-		if (!sid_zero(&nh->nh_srv6->seg6_segs)) {
+		if (nh->nh_srv6->seg6_segs && nh->nh_srv6->seg6_segs->num_segs &&
+		    !sid_zero(nh->nh_srv6->seg6_segs)) {
 			SET_FLAG(znh->flags, ZAPI_NEXTHOP_FLAG_SEG6);
-			memcpy(&znh->seg6_segs, &nh->nh_srv6->seg6_segs,
-			       sizeof(struct in6_addr));
+			znh->seg_num = nh->nh_srv6->seg6_segs->num_segs;
+			for (i = 0; i < nh->nh_srv6->seg6_segs->num_segs; i++)
+				memcpy(&znh->seg6_segs[i],
+				       &nh->nh_srv6->seg6_segs->seg[i],
+				       sizeof(struct in6_addr));
 		}
 	}
 
diff --git a/lib/zclient.h b/lib/zclient.h
index 42c5a5fdac..2a3ce4e488 100644
--- a/lib/zclient.h
+++ b/lib/zclient.h
@@ -438,7 +438,8 @@ struct zapi_nexthop {
 	struct seg6local_context seg6local_ctx;
 
 	/* SRv6 Headend-behaviour */
-	struct in6_addr seg6_segs;
+	int seg_num;
+	struct in6_addr seg6_segs[SRV6_MAX_SEGS];
 };
 
 /*