Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging

# gpg: Signature made Mon 22 Mar 2021 09:35:08 GMT
# gpg:                using RSA key EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  net/eth: Add an assert() and invert if() statement to simplify code
  net/eth: Read ip6_ext_hdr_routing buffer before accessing it
  net/eth: Check iovec has enough data earlier
  net/eth: Check size earlier in _eth_get_rss_ex_dst_addr()
  net/eth: Better describe _eth_get_rss_ex_dst_addr's offset argument
  net/eth: Simplify _eth_get_rss_ex_dst_addr()
  net/eth: Use correct in6_address offset in _eth_get_rss_ex_dst_addr()
  net/colo-compare.c: Optimize removal of secondary packet
  net/colo-compare.c: Fix memory leak for non-tcp packet
  hw/net: virtio-net: Initialize nc->do_not_pad to true
  net: Pad short frames to minimum size before sending from SLiRP/TAP
  net: Add a 'do_not_pad" to NetClientState
  net: eth: Add a helper to pad a short Ethernet frame

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 18 insertions, 0 deletions

diff --git a/include/net/eth.h b/include/net/eth.h
index 0671be6..7767ae8 100644
--- a/include/net/eth.h
+++ b/include/net/eth.h
@@ -31,6 +31,7 @@
 
 #define ETH_ALEN 6
 #define ETH_HLEN 14
+#define ETH_ZLEN 60     /* Min. octets in frame without FCS */
 
 struct eth_header {
     uint8_t  h_dest[ETH_ALEN];   /* destination eth addr */
@@ -422,4 +423,20 @@ bool
 eth_parse_ipv6_hdr(const struct iovec *pkt, int pkt_frags,
                    size_t ip6hdr_off, eth_ip6_hdr_info *info);
 
+/**
+ * eth_pad_short_frame - pad a short frame to the minimum Ethernet frame length
+ *
+ * If the Ethernet frame size is shorter than 60 bytes, it will be padded to
+ * 60 bytes at the address @padded_pkt.
+ *
+ * @padded_pkt: buffer address to hold the padded frame
+ * @padded_buflen: pointer holding length of @padded_pkt. If the frame is
+ *                 padded, the length will be updated to the padded one.
+ * @pkt: address to hold the original Ethernet frame
+ * @pkt_size: size of the original Ethernet frame
+ * @return true if the frame is padded, otherwise false
+ */
+bool eth_pad_short_frame(uint8_t *padded_pkt, size_t *padded_buflen,
+                         const void *pkt, size_t pkt_size);
+
 #endif
diff --git a/include/net/net.h b/include/net/net.h
index a02949f..3559f3c 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -103,6 +103,7 @@ struct NetClientState {
     int vring_enable;
     int vnet_hdr_len;
     bool is_netdev;
+    bool do_not_pad; /* do not pad to the minimum ethernet frame length */
     QTAILQ_HEAD(, NetFilterState) filters;
 };