hw/net/net_tx_pkt: Implement TCP segmentation

There was no proper implementation of TCP segmentation before this
change, and net_tx_pkt relied solely on IPv4 fragmentation. Not only
this is not aligned with the specification, but it also resulted in
corrupted IPv6 packets.

This is particularly problematic for the igb, a new proposed device
implementation; igb provides loopback feature for VMDq and the feature
relies on software segmentation.

Implement proper TCP segmentation in net_tx_pkt to fix such a scenario.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

1 files changed, 0 insertions, 27 deletions

diff --git a/net/eth.c b/net/eth.c
index f074b2f..36d39b4 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -315,33 +315,6 @@ eth_strip_vlan_ex(const struct iovec *iov, int iovcnt, size_t iovoff,
 }
 
 void
-eth_setup_ip4_fragmentation(const void *l2hdr, size_t l2hdr_len,
-                            void *l3hdr, size_t l3hdr_len,
-                            size_t l3payload_len,
-                            size_t frag_offset, bool more_frags)
-{
-    const struct iovec l2vec = {
-        .iov_base = (void *) l2hdr,
-        .iov_len = l2hdr_len
-    };
-
-    if (eth_get_l3_proto(&l2vec, 1, l2hdr_len) == ETH_P_IP) {
-        uint16_t orig_flags;
-        struct ip_header *iphdr = (struct ip_header *) l3hdr;
-        uint16_t frag_off_units = frag_offset / IP_FRAG_UNIT_SIZE;
-        uint16_t new_ip_off;
-
-        assert(frag_offset % IP_FRAG_UNIT_SIZE == 0);
-        assert((frag_off_units & ~IP_OFFMASK) == 0);
-
-        orig_flags = be16_to_cpu(iphdr->ip_off) & ~(IP_OFFMASK|IP_MF);
-        new_ip_off = frag_off_units | orig_flags  | (more_frags ? IP_MF : 0);
-        iphdr->ip_off = cpu_to_be16(new_ip_off);
-        iphdr->ip_len = cpu_to_be16(l3payload_len + l3hdr_len);
-    }
-}
-
-void
 eth_fix_ip4_checksum(void *l3hdr, size_t l3hdr_len)
 {
     struct ip_header *iphdr = (struct ip_header *) l3hdr;