We will need to build the UDP header at other locations than in function
tap_udp6_send(), so we break that part out to a separate function.
Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au>
Signed-off-by: Jon Maloy <jmaloy(a)redhat.com>
---
tap.c | 40 ++++++++++++++++++++++++++++++----------
tap.h | 4 ++++
2 files changed, 34 insertions(+), 10 deletions(-)
diff --git a/tap.c b/tap.c
index c0fa6ab..cb1bdba 100644
--- a/tap.c
+++ b/tap.c
@@ -266,27 +266,22 @@ static void *tap_push_ip6h(struct ipv6hdr *ip6h,
}
/**
- * tap_udp6_send() - Send UDP over IPv6 packet
+ * tap_push_uh6() - Build UDPv6 header with checksum
* @c: Execution context
* @src: IPv6 source address
* @sport: UDP source port
* @dst: IPv6 destination address
* @dport: UDP destination port
* @flow: Flow label
- * @in: UDP payload contents (not including UDP header)
+ * @in: UDP payload contents (not including UDP header)
* @dlen: UDP payload length (not including UDP header)
*/
-void tap_udp6_send(const struct ctx *c,
+void *tap_push_uh6(struct udphdr *uh,
const struct in6_addr *src, in_port_t sport,
const struct in6_addr *dst, in_port_t dport,
- uint32_t flow, void *in, size_t dlen)
+ void *in, size_t dlen)
{
size_t l4len = dlen + sizeof(struct udphdr);
- char buf[USHRT_MAX];
- struct ipv6hdr *ip6h = tap_push_l2h(c, buf, ETH_P_IPV6);
- struct udphdr *uh = tap_push_ip6h(ip6h, src, dst,
- l4len, IPPROTO_UDP, flow);
- char *data = (char *)(uh + 1);
const struct iovec iov = {
.iov_base = in,
.iov_len = dlen
@@ -297,8 +292,33 @@ void tap_udp6_send(const struct ctx *c,
uh->dest = htons(dport);
uh->len = htons(l4len);
csum_udp6(uh, src, dst, &payload);
- memcpy(data, in, dlen);
+ return uh + 1;
+}
+
+/**
+ * tap_udp6_send() - Send UDP over IPv6 packet
+ * @c: Execution context
+ * @src: IPv6 source address
+ * @sport: UDP source port
+ * @dst: IPv6 destination address
+ * @dport: UDP destination port
+ * @flow: Flow label
+ * @in: UDP payload contents (not including UDP header)
+ * @dlen: UDP payload length (not including UDP header)
+ */
+void tap_udp6_send(const struct ctx *c,
+ const struct in6_addr *src, in_port_t sport,
+ const struct in6_addr *dst, in_port_t dport,
+ uint32_t flow, void *in, size_t dlen)
+{
+ size_t l4len = dlen + sizeof(struct udphdr);
+ char buf[USHRT_MAX];
+ struct ipv6hdr *ip6h = tap_push_l2h(c, buf, ETH_P_IPV6);
+ struct udphdr *uh = tap_push_ip6h(ip6h, src, dst,
+ l4len, IPPROTO_UDP, flow);
+ char *data = tap_push_uh6(uh, src, sport, dst, dport, in, dlen);
+ memcpy(data, in, dlen);
tap_send_single(c, buf, dlen + (data - buf));
}
diff --git a/tap.h b/tap.h
index 37da21d..b7b8cef 100644
--- a/tap.h
+++ b/tap.h
@@ -47,6 +47,10 @@ static inline void tap_hdr_update(struct tap_hdr *thdr, size_t l2len)
void *tap_push_uh4(struct udphdr *uh, struct in_addr src, in_port_t sport,
struct in_addr dst, in_port_t dport,
const void *in, size_t dlen);
+void *tap_push_uh6(struct udphdr *uh,
+ const struct in6_addr *src, in_port_t sport,
+ const struct in6_addr *dst, in_port_t dport,
+ void *in, size_t dlen);
void *tap_push_ip4h(struct iphdr *ip4h, struct in_addr src,
struct in_addr dst, size_t l4len, uint8_t proto);
void tap_udp4_send(const struct ctx *c, struct in_addr src, in_port_t sport,
--
2.48.1