net: add IPv6 header extension parsing function

[dpdk.git] / lib / librte_net / rte_ip.h

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index 26b089e..4465073 100644 (file)
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -440,6 +440,56 @@ rte_ipv6_udptcp_cksum(const struct rte_ipv6_hdr *ipv6_hdr, const void *l4_hdr)
        return (uint16_t)cksum;
 }
 
+/* IPv6 fragmentation header size */
+#define RTE_IPV6_FRAG_HDR_SIZE 8
+
+/**
+ * Parse next IPv6 header extension
+ *
+ * This function checks if proto number is an IPv6 extensions and parses its
+ * data if so, providing information on next header and extension length.
+ *
+ * @param p
+ *   Pointer to an extension raw data.
+ * @param proto
+ *   Protocol number extracted from the "next header" field from
+ *   the IPv6 header or the previous extension.
+ * @param ext_len
+ *   Extension data length.
+ * @return
+ *   next protocol number if proto is an IPv6 extension, -EINVAL otherwise
+ */
+__rte_experimental
+static inline int
+rte_ipv6_get_next_ext(uint8_t *p, int proto, size_t *ext_len)
+{
+       int next_proto;
+
+       switch (proto) {
+       case IPPROTO_AH:
+               next_proto = *p++;
+               *ext_len = (*p + 2) * sizeof(uint32_t);
+               break;
+
+       case IPPROTO_HOPOPTS:
+       case IPPROTO_ROUTING:
+       case IPPROTO_DSTOPTS:
+               next_proto = *p++;
+               *ext_len = (*p + 1) * sizeof(uint64_t);
+               break;
+
+       case IPPROTO_FRAGMENT:
+               next_proto = *p;
+               *ext_len = RTE_IPV6_FRAG_HDR_SIZE;
+               break;
+
+       default:
+               return -EINVAL;
+       }
+
+       return next_proto;
+}
+
 #ifdef __cplusplus
 }
 #endif