Streamline the logic here slightly, by introducing a 'src' temporary for brevity. We also transform the logic for setting/clearing PORT_LOOPBACK. This makes udp_update_hdr4() more closely match the corresponding logic from udp_update_udp6(). Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- udp.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/udp.c b/udp.c index 97518d92..87f440f5 100644 --- a/udp.c +++ b/udp.c @@ -583,6 +583,7 @@ 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; in_port_t src_port; size_t ip_len; @@ -591,26 +592,26 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport, b->iph.tot_len = htons(ip_len); b->iph.daddr = c->ip4.addr_seen.s_addr; + src = &b->s_in.sin_addr; src_port = ntohs(b->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) && - src_port == 53) { + IN4_ARE_ADDR_EQUAL(src, &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_ARE_ADDR_EQUAL(&b->s_in.sin_addr, &c->ip4.addr_seen)) { + } 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_port_flags[V4][src_port].ts = now->tv_sec; udp_port_flags[V4][src_port].flags |= PORT_LOCAL; - if (IN4_ARE_ADDR_EQUAL(&b->s_in.sin_addr.s_addr, &c->ip4.addr_seen)) - udp_port_flags[V4][src_port].flags &= ~PORT_LOOPBACK; - else + if (IN4_IS_ADDR_LOOPBACK(src)) udp_port_flags[V4][src_port].flags |= PORT_LOOPBACK; + else + udp_port_flags[V4][src_port].flags &= ~PORT_LOOPBACK; bitmap_set(udp_act[V4][UDP_ACT_FLAGS], src_port); } else { - b->iph.saddr = b->s_in.sin_addr.s_addr; + b->iph.saddr = src->s_addr; } udp_update_check4(b); -- 2.43.2