diff options
Diffstat (limited to 'udp.c')
| -rw-r--r-- | udp.c | 33 |
1 files changed, 30 insertions, 3 deletions
@@ -168,6 +168,7 @@ udp_meta[UDP_MAX_FRAMES]; * @UDP_IOV_ETH Ethernet header * @UDP_IOV_IP IP (v4/v6) header * @UDP_IOV_PAYLOAD IP payload (UDP header + data) + * @UDP_IOV_ETH_PAD Ethernet (802.3) padding to 60 bytes * @UDP_NUM_IOVS the number of entries in the iovec array */ enum udp_iov_idx { @@ -175,6 +176,7 @@ enum udp_iov_idx { UDP_IOV_ETH, UDP_IOV_IP, UDP_IOV_PAYLOAD, + UDP_IOV_ETH_PAD, UDP_NUM_IOVS, }; @@ -239,6 +241,7 @@ static void udp_iov_init_one(const struct ctx *c, size_t i) tiov[UDP_IOV_ETH] = IOV_OF_LVALUE(udp_eth_hdr[i]); tiov[UDP_IOV_TAP] = tap_hdr_iov(c, &meta->taph); tiov[UDP_IOV_PAYLOAD].iov_base = payload; + tiov[UDP_IOV_ETH_PAD].iov_base = eth_pad; mh->msg_iov = siov; mh->msg_iovlen = 1; @@ -345,6 +348,22 @@ size_t udp_update_hdr6(struct ipv6hdr *ip6h, struct udp_payload_t *bp, } /** + * udp_tap_pad() - Calculate padding to send out of padding (zero) buffer + * @iov: Pointer to iovec of frame parts we're about to send + */ +static void udp_tap_pad(struct iovec *iov) +{ + size_t l2len = iov[UDP_IOV_ETH].iov_len + + iov[UDP_IOV_IP].iov_len + + iov[UDP_IOV_PAYLOAD].iov_len; + + if (l2len < ETH_ZLEN) + iov[UDP_IOV_ETH_PAD].iov_len = ETH_ZLEN - l2len; + else + iov[UDP_IOV_ETH_PAD].iov_len = 0; +} + +/** * udp_tap_prepare() - Convert one datagram into a tap frame * @mmh: Receiving mmsghdr array * @idx: Index of the datagram to prepare @@ -362,23 +381,31 @@ static void udp_tap_prepare(const struct mmsghdr *mmh, struct ethhdr *eh = (*tap_iov)[UDP_IOV_ETH].iov_base; struct udp_payload_t *bp = &udp_payload[idx]; struct udp_meta_t *bm = &udp_meta[idx]; - size_t l4len; + size_t l4len, l2len; eth_update_mac(eh, NULL, tap_omac); if (!inany_v4(&toside->eaddr) || !inany_v4(&toside->oaddr)) { l4len = udp_update_hdr6(&bm->ip6h, bp, toside, mmh[idx].msg_len, no_udp_csum); - tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip6h) + ETH_HLEN); + + l2len = MAX(l4len + sizeof(bm->ip6h) + ETH_HLEN, ETH_ZLEN); + tap_hdr_update(&bm->taph, l2len); + eh->h_proto = htons_constant(ETH_P_IPV6); (*tap_iov)[UDP_IOV_IP] = IOV_OF_LVALUE(bm->ip6h); } else { l4len = udp_update_hdr4(&bm->ip4h, bp, toside, mmh[idx].msg_len, no_udp_csum); - tap_hdr_update(&bm->taph, l4len + sizeof(bm->ip4h) + ETH_HLEN); + + l2len = MAX(l4len + sizeof(bm->ip4h) + ETH_HLEN, ETH_ZLEN); + tap_hdr_update(&bm->taph, l2len); + eh->h_proto = htons_constant(ETH_P_IP); (*tap_iov)[UDP_IOV_IP] = IOV_OF_LVALUE(bm->ip4h); } (*tap_iov)[UDP_IOV_PAYLOAD].iov_len = l4len; + + udp_tap_pad(*tap_iov); } /** |