From: Laurent Vivier <lvivier(a)redhat.com>
in udp_update_hdr4():
Assign the source address to src, either b->s_in.sin_addr,
c->ip4.dns_match or c->ip4.gw and then set b->iph.saddr to src->s_addr.
in udp_update_hdr6():
Assign the source address to src, either b->s_in6.sin6_addr,
c->ip6.dns_match, c->ip6.gw or c->ip6.addr_ll.
Assign the destination to dst, either c->ip6.addr_seen or
&c->ip6.addr_ll_seen.
Then set dst to b->ip6h.daddr and src to b->ip6h.saddr.
Signed-off-by: Laurent Vivier <lvivier(a)redhat.com>
Message-ID: <20240303135114.1023026-6-lvivier(a)redhat.com>
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
udp.c | 39 +++++++++++++++++++--------------------
1 file changed, 19 insertions(+), 20 deletions(-)
diff --git a/udp.c b/udp.c
index 26774df7..2b41a1bd 100644
--- a/udp.c
+++ b/udp.c
@@ -588,7 +588,7 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t
dstport,
const struct timespec *now)
{
struct udp4_l2_buf_t *b = &udp4_l2_buf[n];
- struct in_addr *src;
+ const struct in_addr *src;
in_port_t src_port;
size_t ip_len;
@@ -602,10 +602,9 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t
dstport,
if (!IN4_IS_ADDR_UNSPECIFIED(&c->ip4.dns_match) &&
IN4_ARE_ADDR_EQUAL(src, &c->ip4.dns_host) && src_port == 53) {
- b->iph.saddr = c->ip4.dns_match.s_addr;
+ src = &c->ip4.dns_match;
} else if (IN4_IS_ADDR_LOOPBACK(src) ||
IN4_ARE_ADDR_EQUAL(src, &c->ip4.addr_seen)) {
- b->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;
@@ -615,9 +614,10 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t
dstport,
udp_tap_map[V4][src_port].flags &= ~PORT_LOOPBACK;
bitmap_set(udp_act[V4][UDP_ACT_TAP], src_port);
- } else {
- b->iph.saddr = src->s_addr;
+
+ src = &c->ip4.gw;
}
+ b->iph.saddr = src->s_addr;
udp_update_check4(b);
b->uh.source = b->s_in.sin_port;
@@ -640,10 +640,11 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t
dstport,
const struct timespec *now)
{
struct udp6_l2_buf_t *b = &udp6_l2_buf[n];
- struct in6_addr *src;
+ const struct in6_addr *src, *dst;
in_port_t src_port;
size_t ip_len;
+ dst = &c->ip6.addr_seen;
src = &b->s_in6.sin6_addr;
src_port = ntohs(b->s_in6.sin6_port);
@@ -652,23 +653,14 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t
dstport,
b->ip6h.payload_len = htons(udp6_l2_mh_sock[n].msg_len + sizeof(b->uh));
if (IN6_IS_ADDR_LINKLOCAL(src)) {
- b->ip6h.daddr = c->ip6.addr_ll_seen;
- b->ip6h.saddr = b->s_in6.sin6_addr;
+ dst = &c->ip6.addr_ll_seen;
} 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;
+ src = &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;
-
- if (IN6_IS_ADDR_LINKLOCAL(&c->ip6.gw))
- b->ip6h.saddr = c->ip6.gw;
- else
- b->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;
@@ -683,10 +675,17 @@ static size_t udp_update_hdr6(const struct ctx *c, int n, in_port_t
dstport,
udp_tap_map[V6][src_port].flags &= ~PORT_GUA;
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;
+
+ dst = &c->ip6.addr_ll_seen;
+
+ if (IN6_IS_ADDR_LINKLOCAL(&c->ip6.gw))
+ src = &c->ip6.gw;
+ else
+ src = &c->ip6.addr_ll;
+
}
+ b->ip6h.daddr = *dst;
+ b->ip6h.saddr = *src;
b->uh.source = b->s_in6.sin6_port;
b->uh.dest = htons(dstport);
--
2.44.0