[dpdk-dev] [PATCH 1/8] net: export IPv6 header extensions skip function

[Didier Pallard]

skip_ip6_ext function can be exported as a helper, it may be used
by some PMD to skip IPv6 header extensions.

Signed-off-by: Didier Pallard <didier.pallard at 6wind.com>
---
 lib/librte_net/Makefile            |  1 +
 lib/librte_net/rte_net.c           | 21 ++++++++++++++-------
 lib/librte_net/rte_net.h           | 27 +++++++++++++++++++++++++++
 lib/librte_net/rte_net_version.map |  1 +
 4 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/lib/librte_net/Makefile b/lib/librte_net/Makefile
index 95ff54900..85e403f41 100644
--- a/lib/librte_net/Makefile
+++ b/lib/librte_net/Makefile
@@ -5,6 +5,7 @@ include $(RTE_SDK)/mk/rte.vars.mk
 
 LIB = librte_net.a
 
+CFLAGS += -DALLOW_EXPERIMENTAL_API
 CFLAGS += $(WERROR_FLAGS) -I$(SRCDIR) -O3
 LDLIBS += -lrte_mbuf -lrte_eal -lrte_mempool
 
diff --git a/lib/librte_net/rte_net.c b/lib/librte_net/rte_net.c
index 56a13e3c4..9eb7c7438 100644
--- a/lib/librte_net/rte_net.c
+++ b/lib/librte_net/rte_net.c
@@ -178,8 +178,8 @@ ip4_hlen(const struct ipv4_hdr *hdr)
 }
 
 /* parse ipv6 extended headers, update offset and return next proto */
-static uint16_t
-skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
+int __rte_experimental
+rte_net_skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
 	int *frag)
 {
 	struct ext_hdr {
@@ -201,7 +201,7 @@ skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
 			xh = rte_pktmbuf_read(m, *off, sizeof(*xh),
 				&xh_copy);
 			if (xh == NULL)
-				return 0;
+				return -1;
 			*off += (xh->len + 1) * 8;
 			proto = xh->next_hdr;
 			break;
@@ -209,7 +209,7 @@ skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
 			xh = rte_pktmbuf_read(m, *off, sizeof(*xh),
 				&xh_copy);
 			if (xh == NULL)
-				return 0;
+				return -1;
 			*off += 8;
 			proto = xh->next_hdr;
 			*frag = 1;
@@ -220,7 +220,7 @@ skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
 			return proto;
 		}
 	}
-	return 0;
+	return -1;
 }
 
 /* parse mbuf data to get packet type */
@@ -233,6 +233,7 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
 	uint32_t pkt_type = RTE_PTYPE_L2_ETHER;
 	uint32_t off = 0;
 	uint16_t proto;
+	int ret;
 
 	if (hdr_lens == NULL)
 		hdr_lens = &local_hdr_lens;
@@ -316,7 +317,10 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
 		off += hdr_lens->l3_len;
 		pkt_type |= ptype_l3_ip6(proto);
 		if ((pkt_type & RTE_PTYPE_L3_MASK) == RTE_PTYPE_L3_IPV6_EXT) {
-			proto = skip_ip6_ext(proto, m, &off, &frag);
+			ret = rte_net_skip_ip6_ext(proto, m, &off, &frag);
+			if (ret < 0)
+				return pkt_type;
+			proto = ret;
 			hdr_lens->l3_len = off - hdr_lens->l2_len;
 		}
 		if (proto == 0)
@@ -449,7 +453,10 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
 			uint32_t prev_off;
 
 			prev_off = off;
-			proto = skip_ip6_ext(proto, m, &off, &frag);
+			ret = rte_net_skip_ip6_ext(proto, m, &off, &frag);
+			if (ret < 0)
+				return pkt_type;
+			proto = ret;
 			hdr_lens->inner_l3_len += off - prev_off;
 		}
 		if (proto == 0)
diff --git a/lib/librte_net/rte_net.h b/lib/librte_net/rte_net.h
index 0e97901f3..b6ab6e1d5 100644
--- a/lib/librte_net/rte_net.h
+++ b/lib/librte_net/rte_net.h
@@ -29,6 +29,33 @@ struct rte_net_hdr_lens {
 };
 
 /**
+ * Skip IPv6 header extensions.
+ *
+ * This function skips all IPv6 extensions, returning size of
+ * complete header including options and final protocol value.
+ *
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * @param proto
+ *   Protocol field of IPv6 header.
+ * @param m
+ *   The packet mbuf to be parsed.
+ * @param off
+ *   On input, must contain the offset to the first byte following
+ *   IPv6 header, on output, contains offset to the first byte
+ *   of next layer (after any IPv6 extension header)
+ * @param frag
+ *   Contains 1 in output if packet is an IPv6 fragment.
+ * @return
+ *   Protocol that follows IPv6 header.
+ *   -1 if an error occurs during mbuf parsing.
+ */
+int __rte_experimental
+rte_net_skip_ip6_ext(uint16_t proto, const struct rte_mbuf *m, uint32_t *off,
+	int *frag);
+
+/**
  * Parse an Ethernet packet to get its packet type.
  *
  * This function parses the network headers in mbuf data and return its
diff --git a/lib/librte_net/rte_net_version.map b/lib/librte_net/rte_net_version.map
index 213e6fd32..8bc57d51c 100644
--- a/lib/librte_net/rte_net_version.map
+++ b/lib/librte_net/rte_net_version.map
@@ -17,4 +17,5 @@ EXPERIMENTAL {
 	global:
 
 	rte_net_make_rarp_packet;
+	rte_net_skip_ip6_ext;
 } DPDK_17.05;
-- 
2.11.0