Use packet_data() and extract headers using IOV_PEEK_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier
Reviewed-by: David Gibson
---
tap.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)
diff --git a/tap.c b/tap.c
index d7852fad6069..4fbcad3b385f 100644
--- a/tap.c
+++ b/tap.c
@@ -706,28 +706,34 @@ static int tap4_handler(struct ctx *c, const struct pool *in,
i = 0;
resume:
for (seq_count = 0, seq = NULL; i < in->count; i++) {
- size_t l2len, l3len, hlen, l4len;
+ size_t l3len, hlen, l4len;
+ struct ethhdr eh_storage;
+ struct iphdr iph_storage;
+ struct udphdr uh_storage;
const struct ethhdr *eh;
const struct udphdr *uh;
struct iov_tail data;
struct iphdr *iph;
- const char *l4h;
- packet_get(in, i, 0, 0, &l2len);
+ if (!packet_data(in, i, &data))
+ continue;
- eh = packet_get(in, i, 0, sizeof(*eh), &l3len);
+ eh = IOV_PEEK_HEADER(&data, eh_storage);
if (!eh)
continue;
if (ntohs(eh->h_proto) == ETH_P_ARP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
packet_add(pkt, &data);
arp(c, pkt);
continue;
}
- iph = packet_get(in, i, sizeof(*eh), sizeof(*iph), NULL);
+ if (!iov_tail_drop(&data, sizeof(*eh)))
+ continue;
+ l3len = iov_tail_size(&data);
+
+ iph = IOV_PEEK_HEADER(&data, iph_storage);
if (!iph)
continue;
@@ -755,8 +761,9 @@ resume:
if (iph->saddr && c->ip4.addr_seen.s_addr != iph->saddr)
c->ip4.addr_seen.s_addr = iph->saddr;
- l4h = packet_get(in, i, sizeof(*eh) + hlen, l4len, NULL);
- if (!l4h)
+ if (!iov_tail_drop(&data, hlen))
+ continue;
+ if (iov_tail_size(&data) != l4len)
continue;
if (iph->protocol == IPPROTO_ICMP) {
@@ -767,7 +774,6 @@ resume:
tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add(pkt, &data);
icmp_tap_handler(c, PIF_TAP, AF_INET,
&iph->saddr, &iph->daddr,
@@ -775,15 +781,17 @@ resume:
continue;
}
- uh = packet_get(in, i, sizeof(*eh) + hlen, sizeof(*uh), NULL);
+ uh = IOV_PEEK_HEADER(&data, uh_storage);
if (!uh)
continue;
if (iph->protocol == IPPROTO_UDP) {
+ struct iov_tail eh_data;
+
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
- packet_add(pkt, &data);
+ packet_data(in, i, &eh_data);
+ packet_add(pkt, &eh_data);
if (dhcp(c, pkt))
continue;
}
@@ -834,7 +842,6 @@ resume:
#undef L4_SET
append:
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add((struct pool *)&seq->p, &data);
}
--
2.49.0