udp_splice_namebuf is now used only for spliced sending, and so it is
only ever populated with the localhost address, either IPv4 or IPv6.
So, replace the awkward initialization in udp_sock_handler_splice()
with statically initialized versions for IPv4 and IPv6. We then just
need to update the port number in udp_sock_handler_splice().
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
udp.c | 40 ++++++++++++++++++----------------------
util.h | 7 +++++++
2 files changed, 25 insertions(+), 22 deletions(-)
diff --git a/udp.c b/udp.c
index 24fa984..98d8687 100644
--- a/udp.c
+++ b/udp.c
@@ -232,11 +232,18 @@ static struct mmsghdr udp4_l2_mh_tap [UDP_MAX_FRAMES];
static struct mmsghdr udp6_l2_mh_tap [UDP_MAX_FRAMES];
/* recvmmsg()/sendmmsg() data for "spliced" connections */
-static struct sockaddr_storage udp_splice_namebuf;
-
static struct iovec udp4_iov_splice [UDP_MAX_FRAMES];
static struct iovec udp6_iov_splice [UDP_MAX_FRAMES];
+static struct sockaddr_in udp4_localname = {
+ .sin_family = AF_INET,
+ .sin_addr = IN4ADDR_LOOPBACK_INIT,
+};
+static struct sockaddr_in6 udp6_localname = {
+ .sin6_family = AF_INET6,
+ .sin6_addr = IN6ADDR_LOOPBACK_INIT,
+};
+
static struct mmsghdr udp4_mh_splice [UDP_MAX_FRAMES];
static struct mmsghdr udp6_mh_splice [UDP_MAX_FRAMES];
@@ -610,23 +617,10 @@ static void udp_sock_handler_splice(const struct ctx *c, union
epoll_ref ref,
if (n <= 0)
return;
- if (v6) {
- *((struct sockaddr_in6 *)&udp_splice_namebuf) =
- ((struct sockaddr_in6) {
- .sin6_family = AF_INET6,
- .sin6_addr = IN6ADDR_LOOPBACK_INIT,
- .sin6_port = htons(dst),
- .sin6_scope_id = 0,
- });
- } else {
- *((struct sockaddr_in *)&udp_splice_namebuf) =
- ((struct sockaddr_in) {
- .sin_family = AF_INET,
- .sin_addr = { .s_addr = htonl(INADDR_LOOPBACK) },
- .sin_port = htons(dst),
- .sin_zero = { 0 },
- });
- }
+ if (v6)
+ udp6_localname.sin6_port = htons(dst);
+ else
+ udp4_localname.sin_port = htons(dst);
for (i = 0; i < n; i += m) {
in_port_t src = sa_port(v6, mmh_recv[i].msg_hdr.msg_name);
@@ -1252,9 +1246,11 @@ static void udp_splice_iov_init(void)
struct msghdr *mh4 = &udp4_mh_splice[i].msg_hdr;
struct msghdr *mh6 = &udp6_mh_splice[i].msg_hdr;
- mh4->msg_name = mh6->msg_name = &udp_splice_namebuf;
- mh4->msg_namelen = sizeof(udp_splice_namebuf);
- mh6->msg_namelen = sizeof(udp_splice_namebuf);
+ mh4->msg_name = &udp4_localname;
+ mh4->msg_namelen = sizeof(udp4_localname);
+
+ mh6->msg_name = &udp6_localname;
+ mh6->msg_namelen = sizeof(udp6_localname);
udp4_iov_splice[i].iov_base = udp4_l2_buf[i].data;
udp6_iov_splice[i].iov_base = udp6_l2_buf[i].data;
diff --git a/util.h b/util.h
index 02b55a9..3baec91 100644
--- a/util.h
+++ b/util.h
@@ -79,6 +79,13 @@
(IN_MULTICAST(ntohl((a)->s_addr)))
#define IN4_ARE_ADDR_EQUAL(a, b) \
(((struct in_addr *)(a))->s_addr == ((struct in_addr *)b)->s_addr)
+#if __BYTE_ORDER == __BIG_ENDIAN
+#define IN4ADDR_LOOPBACK_INIT \
+ { .s_addr = INADDR_LOOPBACK }
+#else
+#define IN4ADDR_LOOPBACK_INIT \
+ { .s_addr = __bswap_constant_32(INADDR_LOOPBACK) }
+#endif
#define NS_FN_STACK_SIZE (RLIMIT_STACK_VAL * 1024 / 8)
int do_clone(int (*fn)(void *), char *stack_area, size_t stack_size, int flags,
--
2.38.1