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Diffstat (limited to 'udp.c')
-rw-r--r--udp.c132
1 files changed, 55 insertions, 77 deletions
diff --git a/udp.c b/udp.c
index c940749..3abafc9 100644
--- a/udp.c
+++ b/udp.c
@@ -189,44 +189,27 @@ udp_payload[UDP_MAX_FRAMES];
/* Ethernet header for IPv4 frames */
static struct ethhdr udp4_eth_hdr;
-/**
- * udp4_l2_buf_t - Pre-cooked IPv4 packet buffers for tap connections
- * @s_in: Source socket address, filled in by recvmmsg()
- * @taph: Tap backend specific header
- * @iph: Pre-filled IP header (except for tot_len and saddr)
- */
-static struct udp4_l2_buf_t {
- struct sockaddr_in s_in;
-
- struct tap_hdr taph;
- struct iphdr iph;
-} __attribute__ ((packed, aligned(__alignof__(unsigned int))))
-udp4_l2_buf[UDP_MAX_FRAMES];
-
/* Ethernet header for IPv6 frames */
static struct ethhdr udp6_eth_hdr;
/**
- * udp6_l2_buf_t - Pre-cooked IPv6 packet buffers for tap connections
- * @s_in6: Source socket address, filled in by recvmmsg()
+ * struct udp_meta_t - Pre-cooked headers and metadata for UDP packets
+ * @ip6h: Pre-filled IPv6 header (except for payload_len and addresses)
+ * @ip4h: Pre-filled IPv4 header (except for tot_len and saddr)
* @taph: Tap backend specific header
- * @ip6h: Pre-filled IP header (except for payload_len and addresses)
+ * @s_in: Source socket address, filled in by recvmmsg()
*/
-struct udp6_l2_buf_t {
- struct sockaddr_in6 s_in6;
-#ifdef __AVX2__
- /* Align ip6h to 32-byte boundary. */
- uint8_t pad[64 - (sizeof(struct sockaddr_in6) + sizeof(struct tap_hdr))];
-#endif
-
- struct tap_hdr taph;
+static struct udp_meta_t {
struct ipv6hdr ip6h;
+ struct iphdr ip4h;
+ struct tap_hdr taph;
+
+ union sockaddr_inany s_in;
+}
#ifdef __AVX2__
-} __attribute__ ((packed, aligned(32)))
-#else
-} __attribute__ ((packed, aligned(__alignof__(unsigned int))))
+__attribute__ ((aligned(32)))
#endif
-udp6_l2_buf[UDP_MAX_FRAMES];
+udp_meta[UDP_MAX_FRAMES];
/**
* enum udp_iov_idx - Indices for the buffers making up a single UDP frame
@@ -321,6 +304,12 @@ static void udp_iov_init_one(const struct ctx *c, size_t i)
{
struct udp_payload_t *payload = &udp_payload[i];
struct iovec *siov = &udp_l2_iov_sock[i];
+ struct udp_meta_t *meta = &udp_meta[i];
+
+ *meta = (struct udp_meta_t) {
+ .ip4h = L2_BUF_IP4_INIT(IPPROTO_UDP),
+ .ip6h = L2_BUF_IP6_INIT(IPPROTO_UDP),
+ };
*siov = IOV_OF_LVALUE(payload->data);
udp4_eth_hdr.h_proto = htons_constant(ETH_P_IP);
@@ -328,41 +317,31 @@ static void udp_iov_init_one(const struct ctx *c, size_t i)
if (c->ifi4) {
struct msghdr *mh = &udp4_l2_mh_sock[i].msg_hdr;
- struct udp4_l2_buf_t *buf = &udp4_l2_buf[i];
struct iovec *tiov = udp4_l2_iov_tap[i];
- *buf = (struct udp4_l2_buf_t) {
- .iph = L2_BUF_IP4_INIT(IPPROTO_UDP)
- };
-
- mh->msg_name = &buf->s_in;
- mh->msg_namelen = sizeof(buf->s_in);
+ mh->msg_name = &meta->s_in;
+ mh->msg_namelen = sizeof(struct sockaddr_in);
mh->msg_iov = siov;
mh->msg_iovlen = 1;
- tiov[UDP_IOV_TAP] = tap_hdr_iov(c, &buf->taph);
+ tiov[UDP_IOV_TAP] = tap_hdr_iov(c, &meta->taph);
tiov[UDP_IOV_ETH] = IOV_OF_LVALUE(udp4_eth_hdr);
- tiov[UDP_IOV_IP] = IOV_OF_LVALUE(buf->iph);
+ tiov[UDP_IOV_IP] = IOV_OF_LVALUE(meta->ip4h);
tiov[UDP_IOV_PAYLOAD].iov_base = payload;
}
if (c->ifi6) {
struct msghdr *mh = &udp6_l2_mh_sock[i].msg_hdr;
- struct udp6_l2_buf_t *buf = &udp6_l2_buf[i];
struct iovec *tiov = udp6_l2_iov_tap[i];
- *buf = (struct udp6_l2_buf_t) {
- .ip6h = L2_BUF_IP6_INIT(IPPROTO_UDP)
- };
-
- mh->msg_name = &buf->s_in6;
- mh->msg_namelen = sizeof(buf->s_in6);
+ mh->msg_name = &meta->s_in;
+ mh->msg_namelen = sizeof(struct sockaddr_in6);
mh->msg_iov = siov;
mh->msg_iovlen = 1;
- tiov[UDP_IOV_TAP] = tap_hdr_iov(c, &buf->taph);
+ tiov[UDP_IOV_TAP] = tap_hdr_iov(c, &meta->taph);
tiov[UDP_IOV_ETH] = IOV_OF_LVALUE(udp6_eth_hdr);
- tiov[UDP_IOV_IP] = IOV_OF_LVALUE(buf->ip6h);
+ tiov[UDP_IOV_IP] = IOV_OF_LVALUE(meta->ip6h);
tiov[UDP_IOV_PAYLOAD].iov_base = payload;
}
}
@@ -577,7 +556,7 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
/**
* udp_update_hdr4() - Update headers for one IPv4 datagram
* @c: Execution context
- * @bh: Pointer to udp4_l2_buf to update
+ * @bm: Pointer to udp_meta_t to update
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -585,16 +564,16 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
*
* Return: size of IPv4 payload (UDP header + data)
*/
-static size_t udp_update_hdr4(const struct ctx *c, struct udp4_l2_buf_t *bh,
- struct udp_payload_t *bp,
+static size_t udp_update_hdr4(const struct ctx *c,
+ struct udp_meta_t *bm, struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- in_port_t srcport = ntohs(bh->s_in.sin_port);
+ in_port_t srcport = ntohs(bm->s_in.sa4.sin_port);
const struct in_addr dst = c->ip4.addr_seen;
- struct in_addr src = bh->s_in.sin_addr;
+ struct in_addr src = bm->s_in.sa4.sin_addr;
size_t l4len = dlen + sizeof(bp->uh);
- size_t l3len = l4len + sizeof(bh->iph);
+ size_t l3len = l4len + sizeof(bm->ip4h);
if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
IN4_ARE_ADDR_EQUAL(&src, &c->ip4.dns_host) && srcport == 53 &&
@@ -615,24 +594,24 @@ static size_t udp_update_hdr4(const struct ctx *c, struct udp4_l2_buf_t *bh,
src = c->ip4.gw;
}
- bh->iph.tot_len = htons(l3len);
- bh->iph.daddr = dst.s_addr;
- bh->iph.saddr = src.s_addr;
- bh->iph.check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
+ bm->ip4h.tot_len = htons(l3len);
+ bm->ip4h.daddr = dst.s_addr;
+ bm->ip4h.saddr = src.s_addr;
+ bm->ip4h.check = csum_ip4_header(l3len, IPPROTO_UDP, src, dst);
- bp->uh.source = bh->s_in.sin_port;
+ bp->uh.source = bm->s_in.sa4.sin_port;
bp->uh.dest = htons(dstport);
bp->uh.len = htons(l4len);
csum_udp4(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bh->taph, l3len + sizeof(udp4_eth_hdr));
+ tap_hdr_update(&bm->taph, l3len + sizeof(udp4_eth_hdr));
return l4len;
}
/**
* udp_update_hdr6() - Update headers for one IPv6 datagram
* @c: Execution context
- * @bh: Pointer to udp6_l2_buf to update
+ * @bm: Pointer to udp_meta_t to update
* @bp: Pointer to udp_payload_t to update
* @dstport: Destination port number
* @dlen: Length of UDP payload
@@ -640,14 +619,14 @@ static size_t udp_update_hdr4(const struct ctx *c, struct udp4_l2_buf_t *bh,
*
* Return: size of IPv6 payload (UDP header + data)
*/
-static size_t udp_update_hdr6(const struct ctx *c, struct udp6_l2_buf_t *bh,
- struct udp_payload_t *bp,
+static size_t udp_update_hdr6(const struct ctx *c,
+ struct udp_meta_t *bm, struct udp_payload_t *bp,
in_port_t dstport, size_t dlen,
const struct timespec *now)
{
- const struct in6_addr *src = &bh->s_in6.sin6_addr;
+ const struct in6_addr *src = &bm->s_in.sa6.sin6_addr;
const struct in6_addr *dst = &c->ip6.addr_seen;
- in_port_t srcport = ntohs(bh->s_in6.sin6_port);
+ in_port_t srcport = ntohs(bm->s_in.sa6.sin6_port);
uint16_t l4len = dlen + sizeof(bp->uh);
if (IN6_IS_ADDR_LINKLOCAL(src)) {
@@ -684,19 +663,19 @@ static size_t udp_update_hdr6(const struct ctx *c, struct udp6_l2_buf_t *bh,
}
- bh->ip6h.payload_len = htons(l4len);
- bh->ip6h.daddr = *dst;
- bh->ip6h.saddr = *src;
- bh->ip6h.version = 6;
- bh->ip6h.nexthdr = IPPROTO_UDP;
- bh->ip6h.hop_limit = 255;
+ bm->ip6h.payload_len = htons(l4len);
+ bm->ip6h.daddr = *dst;
+ bm->ip6h.saddr = *src;
+ bm->ip6h.version = 6;
+ bm->ip6h.nexthdr = IPPROTO_UDP;
+ bm->ip6h.hop_limit = 255;
- bp->uh.source = bh->s_in6.sin6_port;
+ bp->uh.source = bm->s_in.sa6.sin6_port;
bp->uh.dest = htons(dstport);
- bp->uh.len = bh->ip6h.payload_len;
+ bp->uh.len = bm->ip6h.payload_len;
csum_udp6(&bp->uh, src, dst, bp->data, dlen);
- tap_hdr_update(&bh->taph, l4len + sizeof(bh->ip6h) + sizeof(udp6_eth_hdr));
+ tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + sizeof(udp6_eth_hdr));
return l4len;
}
@@ -725,15 +704,14 @@ static void udp_tap_send(const struct ctx *c,
for (i = start; i < start + n; i++) {
struct udp_payload_t *bp = &udp_payload[i];
+ struct udp_meta_t *bm = &udp_meta[i];
size_t l4len;
if (v6) {
- l4len = udp_update_hdr6(c, &udp6_l2_buf[i], bp,
- dstport,
+ l4len = udp_update_hdr6(c, bm, bp, dstport,
udp6_l2_mh_sock[i].msg_len, now);
} else {
- l4len = udp_update_hdr4(c, &udp4_l2_buf[i], bp,
- dstport,
+ l4len = udp_update_hdr4(c, bm, bp, dstport,
udp4_l2_mh_sock[i].msg_len, now);
}
tap_iov[i][UDP_IOV_PAYLOAD].iov_len = l4len;