[PATCH 14/24] udp: move udpX_l2_buf_t and udpX_l2_mh_sock out of udp_update_hdrX()

[Laurent Vivier <lvivier@redhat.com>]

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 udp.c | 126 ++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 73 insertions(+), 53 deletions(-)

diff --git a/udp.c b/udp.c
index db635742319b..77168fb0a2af 100644
--- a/udp.c
+++ b/udp.c
@@ -562,47 +562,48 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
  *
  * Return: size of tap frame with headers
  */
-static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport,
-			      const struct timespec *now)
+static size_t udp_update_hdr4(const struct ctx *c, struct iphdr *iph,
+			      size_t data_len, struct sockaddr_in *s_in,
+			      in_port_t dstport, const struct timespec *now)
 {
-	struct udp4_l2_buf_t *b = &udp4_l2_buf[n];
+	struct udphdr *uh = (struct udphdr *)(iph + 1);
 	in_port_t src_port;
 	size_t ip_len;
 
-	ip_len = udp4_l2_mh_sock[n].msg_len + sizeof(b->iph) + sizeof(b->uh);
+	ip_len = data_len + sizeof(struct iphdr) + sizeof(struct udphdr);
 
-	b->iph.tot_len = htons(ip_len);
-	b->iph.daddr = c->ip4.addr_seen.s_addr;
+	iph->tot_len = htons(ip_len);
+	iph->daddr = c->ip4.addr_seen.s_addr;
 
-	src_port = ntohs(b->s_in.sin_port);
+	src_port = ntohs(s_in->sin_port);
 
 	if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
-	    IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr, &c->ip4.dns_host) &&
+	    IN4_ARE_ADDR_EQUAL(&s_in->sin_addr, &c->ip4.dns_host) &&
 	    src_port == 53) {
-		b->iph.saddr = c->ip4.dns_match.s_addr;
-	} else if (IN4_IS_ADDR_LOOPBACK(&b->s_in.sin_addr) ||
-		   IN4_IS_ADDR_UNSPECIFIED(&b->s_in.sin_addr)||
-		   IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr, &c->ip4.addr_seen)) {
-		b->iph.saddr = c->ip4.gw.s_addr;
+		iph->saddr = c->ip4.dns_match.s_addr;
+	} else if (IN4_IS_ADDR_LOOPBACK(&s_in->sin_addr) ||
+		   IN4_IS_ADDR_UNSPECIFIED(&s_in->sin_addr)||
+		   IN4_ARE_ADDR_EQUAL(&s_in->sin_addr, &c->ip4.addr_seen)) {
+		iph->saddr = c->ip4.gw.s_addr;
 		udp_tap_map[V4][src_port].ts = now->tv_sec;
 		udp_tap_map[V4][src_port].flags |= PORT_LOCAL;
 
-		if (IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr.s_addr, &c->ip4.addr_seen))
+		if (IN4_ARE_ADDR_EQUAL(&s_in->sin_addr.s_addr, &c->ip4.addr_seen))
 			udp_tap_map[V4][src_port].flags &= ~PORT_LOOPBACK;
 		else
 			udp_tap_map[V4][src_port].flags |= PORT_LOOPBACK;
 
 		bitmap_set(udp_act[V4][UDP_ACT_TAP], src_port);
 	} else {
-		b->iph.saddr = b->s_in.sin_addr.s_addr;
+		iph->saddr = s_in->sin_addr.s_addr;
 	}
 
-	b->iph.check = ipv4_hdr_checksum(&b->iph, IPPROTO_UDP);
-	b->uh.source = b->s_in.sin_port;
-	b->uh.dest = htons(dstport);
-	b->uh.len = htons(udp4_l2_mh_sock[n].msg_len + sizeof(b->uh));
+	iph->check = ipv4_hdr_checksum(iph, IPPROTO_UDP);
+	uh->source = s_in->sin_port;
+	uh->dest = htons(dstport);
+	uh->len= htons(data_len + sizeof(struct udphdr));
 
-	return tap_iov_len(c, &b->taph, ip_len);
+	return ip_len;
 }
 
 /**
@@ -614,38 +615,39 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport,
  *
  * Return: size of tap frame with headers
  */
-static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
-			      const struct timespec *now)
+static size_t udp_update_hdr6(const struct ctx *c, struct ipv6hdr *ip6h,
+			      size_t data_len, struct sockaddr_in6 *s_in6,
+			      in_port_t dstport, const struct timespec *now)
 {
-	struct udp6_l2_buf_t *b = &udp6_l2_buf[n];
+	struct udphdr *uh = (struct udphdr *)(ip6h + 1);
 	struct in6_addr *src;
 	in_port_t src_port;
 	size_t ip_len;
 
-	src = &b->s_in6.sin6_addr;
-	src_port = ntohs(b->s_in6.sin6_port);
+	src = &s_in6->sin6_addr;
+	src_port = ntohs(s_in6->sin6_port);
 
-	ip_len = udp6_l2_mh_sock[n].msg_len + sizeof(b->ip6h) + sizeof(b->uh);
+	ip_len = data_len + sizeof(struct ipv6hdr) + sizeof(struct udphdr);
 
-	b->ip6h.payload_len = htons(udp6_l2_mh_sock[n].msg_len + sizeof(b->uh));
+	ip6h->payload_len = htons(data_len + sizeof(struct udphdr));
 
 	if (IN6_IS_ADDR_LINKLOCAL(src)) {
-		b->ip6h.daddr = c->ip6.addr_ll_seen;
-		b->ip6h.saddr = b->s_in6.sin6_addr;
+		ip6h->daddr = c->ip6.addr_ll_seen;
+		ip6h->saddr = s_in6->sin6_addr;
 	} else if (!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match) &&
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.dns_host) &&
 		   src_port == 53) {
-		b->ip6h.daddr = c->ip6.addr_seen;
-		b->ip6h.saddr = c->ip6.dns_match;
+		ip6h->daddr = c->ip6.addr_seen;
+		ip6h->saddr = c->ip6.dns_match;
 	} else if (IN6_IS_ADDR_LOOPBACK(src)			||
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.addr_seen)	||
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.addr)) {
-		b->ip6h.daddr = c->ip6.addr_ll_seen;
+		ip6h->daddr = c->ip6.addr_ll_seen;
 
 		if (IN6_IS_ADDR_LINKLOCAL(&c->ip6.gw))
-			b->ip6h.saddr = c->ip6.gw;
+			ip6h->saddr = c->ip6.gw;
 		else
-			b->ip6h.saddr = c->ip6.addr_ll;
+			ip6h->saddr = c->ip6.addr_ll;
 
 		udp_tap_map[V6][src_port].ts = now->tv_sec;
 		udp_tap_map[V6][src_port].flags |= PORT_LOCAL;
@@ -662,20 +664,20 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
 
 		bitmap_set(udp_act[V6][UDP_ACT_TAP], src_port);
 	} else {
-		b->ip6h.daddr = c->ip6.addr_seen;
-		b->ip6h.saddr = b->s_in6.sin6_addr;
+		ip6h->daddr = c->ip6.addr_seen;
+		ip6h->saddr = s_in6->sin6_addr;
 	}
 
-	b->uh.source = b->s_in6.sin6_port;
-	b->uh.dest = htons(dstport);
-	b->uh.len = b->ip6h.payload_len;
-	b->uh.check = csum(&b->uh, ntohs(b->ip6h.payload_len),
-			 proto_ipv6_header_checksum(&b->ip6h, IPPROTO_UDP));
-	b->ip6h.version = 6;
-	b->ip6h.nexthdr = IPPROTO_UDP;
-	b->ip6h.hop_limit = 255;
+	uh->source = s_in6->sin6_port;
+	uh->dest = htons(dstport);
+	uh->len = ip6h->payload_len;
+	uh->check = csum(uh, ntohs(ip6h->payload_len),
+			 proto_ipv6_header_checksum(ip6h, IPPROTO_UDP));
+	ip6h->version = 6;
+	ip6h->nexthdr = IPPROTO_UDP;
+	ip6h->hop_limit = 255;
 
-	return tap_iov_len(c, &b->taph, ip_len);
+	return ip_len;
 }
 
 /**
@@ -689,6 +691,11 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
  *
  * Return: size of tap frame with headers
  */
+#pragma GCC diagnostic push
+/* ignore unaligned pointer value warning for &udp6_l2_buf[i].ip6h and 
+ * &udp4_l2_buf[i].iph
+ */
+#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
 static void udp_tap_send(const struct ctx *c,
 			 unsigned int start, unsigned int n,
 			 in_port_t dstport, bool v6, const struct timespec *now)
@@ -702,18 +709,31 @@ static void udp_tap_send(const struct ctx *c,
 		tap_iov = udp4_l2_iov_tap;
 
 	for (i = start; i < start + n; i++) {
-		size_t buf_len;
-
-		if (v6)
-			buf_len = udp_update_hdr6(c, i, dstport, now);
-		else
-			buf_len = udp_update_hdr4(c, i, dstport, now);
-
-		tap_iov[i].iov_len = buf_len;
+		size_t ip_len;
+
+		if (v6) {
+			ip_len = udp_update_hdr6(c, &udp6_l2_buf[i].ip6h,
+						 udp6_l2_mh_sock[i].msg_len,
+						 &udp6_l2_buf[i].s_in6, dstport,
+						 now);
+			tap_iov[i].iov_len = tap_iov_len(c,
+							 &udp6_l2_buf[i].taph,
+							 ip_len);
+		} else {
+			ip_len = udp_update_hdr4(c, &udp4_l2_buf[i].iph,
+						 udp4_l2_mh_sock[i].msg_len,
+						 &udp4_l2_buf[i].s_in,
+						 dstport, now);
+
+			tap_iov[i].iov_len = tap_iov_len(c,
+							 &udp4_l2_buf[i].taph,
+							 ip_len);
+		}
 	}
 
 	tap_send_frames(c, tap_iov + start, n);
 }
+#pragma GCC diagnostic pop
 
 /**
  * udp_sock_handler() - Handle new data from socket
-- 
@@ -562,47 +562,48 @@ static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
  *
  * Return: size of tap frame with headers
  */
-static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport,
-			      const struct timespec *now)
+static size_t udp_update_hdr4(const struct ctx *c, struct iphdr *iph,
+			      size_t data_len, struct sockaddr_in *s_in,
+			      in_port_t dstport, const struct timespec *now)
 {
-	struct udp4_l2_buf_t *b = &udp4_l2_buf[n];
+	struct udphdr *uh = (struct udphdr *)(iph + 1);
 	in_port_t src_port;
 	size_t ip_len;
 
-	ip_len = udp4_l2_mh_sock[n].msg_len + sizeof(b->iph) + sizeof(b->uh);
+	ip_len = data_len + sizeof(struct iphdr) + sizeof(struct udphdr);
 
-	b->iph.tot_len = htons(ip_len);
-	b->iph.daddr = c->ip4.addr_seen.s_addr;
+	iph->tot_len = htons(ip_len);
+	iph->daddr = c->ip4.addr_seen.s_addr;
 
-	src_port = ntohs(b->s_in.sin_port);
+	src_port = ntohs(s_in->sin_port);
 
 	if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
-	    IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr, &c->ip4.dns_host) &&
+	    IN4_ARE_ADDR_EQUAL(&s_in->sin_addr, &c->ip4.dns_host) &&
 	    src_port == 53) {
-		b->iph.saddr = c->ip4.dns_match.s_addr;
-	} else if (IN4_IS_ADDR_LOOPBACK(&b->s_in.sin_addr) ||
-		   IN4_IS_ADDR_UNSPECIFIED(&b->s_in.sin_addr)||
-		   IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr, &c->ip4.addr_seen)) {
-		b->iph.saddr = c->ip4.gw.s_addr;
+		iph->saddr = c->ip4.dns_match.s_addr;
+	} else if (IN4_IS_ADDR_LOOPBACK(&s_in->sin_addr) ||
+		   IN4_IS_ADDR_UNSPECIFIED(&s_in->sin_addr)||
+		   IN4_ARE_ADDR_EQUAL(&s_in->sin_addr, &c->ip4.addr_seen)) {
+		iph->saddr = c->ip4.gw.s_addr;
 		udp_tap_map[V4][src_port].ts = now->tv_sec;
 		udp_tap_map[V4][src_port].flags |= PORT_LOCAL;
 
-		if (IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr.s_addr, &c->ip4.addr_seen))
+		if (IN4_ARE_ADDR_EQUAL(&s_in->sin_addr.s_addr, &c->ip4.addr_seen))
 			udp_tap_map[V4][src_port].flags &= ~PORT_LOOPBACK;
 		else
 			udp_tap_map[V4][src_port].flags |= PORT_LOOPBACK;
 
 		bitmap_set(udp_act[V4][UDP_ACT_TAP], src_port);
 	} else {
-		b->iph.saddr = b->s_in.sin_addr.s_addr;
+		iph->saddr = s_in->sin_addr.s_addr;
 	}
 
-	b->iph.check = ipv4_hdr_checksum(&b->iph, IPPROTO_UDP);
-	b->uh.source = b->s_in.sin_port;
-	b->uh.dest = htons(dstport);
-	b->uh.len = htons(udp4_l2_mh_sock[n].msg_len + sizeof(b->uh));
+	iph->check = ipv4_hdr_checksum(iph, IPPROTO_UDP);
+	uh->source = s_in->sin_port;
+	uh->dest = htons(dstport);
+	uh->len= htons(data_len + sizeof(struct udphdr));
 
-	return tap_iov_len(c, &b->taph, ip_len);
+	return ip_len;
 }
 
 /**
@@ -614,38 +615,39 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport,
  *
  * Return: size of tap frame with headers
  */
-static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
-			      const struct timespec *now)
+static size_t udp_update_hdr6(const struct ctx *c, struct ipv6hdr *ip6h,
+			      size_t data_len, struct sockaddr_in6 *s_in6,
+			      in_port_t dstport, const struct timespec *now)
 {
-	struct udp6_l2_buf_t *b = &udp6_l2_buf[n];
+	struct udphdr *uh = (struct udphdr *)(ip6h + 1);
 	struct in6_addr *src;
 	in_port_t src_port;
 	size_t ip_len;
 
-	src = &b->s_in6.sin6_addr;
-	src_port = ntohs(b->s_in6.sin6_port);
+	src = &s_in6->sin6_addr;
+	src_port = ntohs(s_in6->sin6_port);
 
-	ip_len = udp6_l2_mh_sock[n].msg_len + sizeof(b->ip6h) + sizeof(b->uh);
+	ip_len = data_len + sizeof(struct ipv6hdr) + sizeof(struct udphdr);
 
-	b->ip6h.payload_len = htons(udp6_l2_mh_sock[n].msg_len + sizeof(b->uh));
+	ip6h->payload_len = htons(data_len + sizeof(struct udphdr));
 
 	if (IN6_IS_ADDR_LINKLOCAL(src)) {
-		b->ip6h.daddr = c->ip6.addr_ll_seen;
-		b->ip6h.saddr = b->s_in6.sin6_addr;
+		ip6h->daddr = c->ip6.addr_ll_seen;
+		ip6h->saddr = s_in6->sin6_addr;
 	} else if (!IN6_IS_ADDR_UNSPECIFIED(&c->ip6.dns_match) &&
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.dns_host) &&
 		   src_port == 53) {
-		b->ip6h.daddr = c->ip6.addr_seen;
-		b->ip6h.saddr = c->ip6.dns_match;
+		ip6h->daddr = c->ip6.addr_seen;
+		ip6h->saddr = c->ip6.dns_match;
 	} else if (IN6_IS_ADDR_LOOPBACK(src)			||
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.addr_seen)	||
 		   IN6_ARE_ADDR_EQUAL(src, &c->ip6.addr)) {
-		b->ip6h.daddr = c->ip6.addr_ll_seen;
+		ip6h->daddr = c->ip6.addr_ll_seen;
 
 		if (IN6_IS_ADDR_LINKLOCAL(&c->ip6.gw))
-			b->ip6h.saddr = c->ip6.gw;
+			ip6h->saddr = c->ip6.gw;
 		else
-			b->ip6h.saddr = c->ip6.addr_ll;
+			ip6h->saddr = c->ip6.addr_ll;
 
 		udp_tap_map[V6][src_port].ts = now->tv_sec;
 		udp_tap_map[V6][src_port].flags |= PORT_LOCAL;
@@ -662,20 +664,20 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
 
 		bitmap_set(udp_act[V6][UDP_ACT_TAP], src_port);
 	} else {
-		b->ip6h.daddr = c->ip6.addr_seen;
-		b->ip6h.saddr = b->s_in6.sin6_addr;
+		ip6h->daddr = c->ip6.addr_seen;
+		ip6h->saddr = s_in6->sin6_addr;
 	}
 
-	b->uh.source = b->s_in6.sin6_port;
-	b->uh.dest = htons(dstport);
-	b->uh.len = b->ip6h.payload_len;
-	b->uh.check = csum(&b->uh, ntohs(b->ip6h.payload_len),
-			 proto_ipv6_header_checksum(&b->ip6h, IPPROTO_UDP));
-	b->ip6h.version = 6;
-	b->ip6h.nexthdr = IPPROTO_UDP;
-	b->ip6h.hop_limit = 255;
+	uh->source = s_in6->sin6_port;
+	uh->dest = htons(dstport);
+	uh->len = ip6h->payload_len;
+	uh->check = csum(uh, ntohs(ip6h->payload_len),
+			 proto_ipv6_header_checksum(ip6h, IPPROTO_UDP));
+	ip6h->version = 6;
+	ip6h->nexthdr = IPPROTO_UDP;
+	ip6h->hop_limit = 255;
 
-	return tap_iov_len(c, &b->taph, ip_len);
+	return ip_len;
 }
 
 /**
@@ -689,6 +691,11 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t dstport,
  *
  * Return: size of tap frame with headers
  */
+#pragma GCC diagnostic push
+/* ignore unaligned pointer value warning for &udp6_l2_buf[i].ip6h and 
+ * &udp4_l2_buf[i].iph
+ */
+#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
 static void udp_tap_send(const struct ctx *c,
 			 unsigned int start, unsigned int n,
 			 in_port_t dstport, bool v6, const struct timespec *now)
@@ -702,18 +709,31 @@ static void udp_tap_send(const struct ctx *c,
 		tap_iov = udp4_l2_iov_tap;
 
 	for (i = start; i < start + n; i++) {
-		size_t buf_len;
-
-		if (v6)
-			buf_len = udp_update_hdr6(c, i, dstport, now);
-		else
-			buf_len = udp_update_hdr4(c, i, dstport, now);
-
-		tap_iov[i].iov_len = buf_len;
+		size_t ip_len;
+
+		if (v6) {
+			ip_len = udp_update_hdr6(c, &udp6_l2_buf[i].ip6h,
+						 udp6_l2_mh_sock[i].msg_len,
+						 &udp6_l2_buf[i].s_in6, dstport,
+						 now);
+			tap_iov[i].iov_len = tap_iov_len(c,
+							 &udp6_l2_buf[i].taph,
+							 ip_len);
+		} else {
+			ip_len = udp_update_hdr4(c, &udp4_l2_buf[i].iph,
+						 udp4_l2_mh_sock[i].msg_len,
+						 &udp4_l2_buf[i].s_in,
+						 dstport, now);
+
+			tap_iov[i].iov_len = tap_iov_len(c,
+							 &udp4_l2_buf[i].taph,
+							 ip_len);
+		}
 	}
 
 	tap_send_frames(c, tap_iov + start, n);
 }
+#pragma GCC diagnostic pop
 
 /**
  * udp_sock_handler() - Handle new data from socket
-- 
2.42.0