diff options
| author |   Neale Ranns <neale.ranns@cisco.com> | 2018-02-09 06:05:16 -0800 |
|---|---|---|
| committer |   Damjan Marion <dmarion.lists@gmail.com> | 2018-02-12 11:23:33 +0000 |
| commit | ffd78d1ef8fe80d1b756a71d42d5eadda60ae996 (patch) | |
| tree | 99770e8773a7c3dd27c8b9b116edb6a39ace09ea /src/vnet/ip | |
| parent | 2d6f66e1748be190664cbd72c826db32616d759a (diff) | |
Improve MTU handling
- setting MTU on an interface updates the L3 max bytes too
- value cached in the adjacency is also updated
- MTU exceeded generates ICMP to sender
Change-Id: I343ec71d8e903b529594c4bd0543f04bc7f370b3
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
Diffstat (limited to 'src/vnet/ip')
| -rw-r--r-- | src/vnet/ip/ip4_forward.c | 43 |
1 files changed, 30 insertions, 13 deletions
diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c index ae4510626d0..b9875d72b8e 100644 --- a/src/vnet/ip/ip4_forward.c +++ b/src/vnet/ip/ip4_forward.c @@ -2109,16 +2109,26 @@ ip4_rewrite_inline (vlib_main_t * vm, vnet_buffer (p1)->ip.save_rewrite_length = rw_len1; /* Check MTU of outgoing interface. */ - error0 = - (vlib_buffer_length_in_chain (vm, p0) > - adj0[0]. - rewrite_header.max_l3_packet_bytes ? IP4_ERROR_MTU_EXCEEDED : - error0); - error1 = - (vlib_buffer_length_in_chain (vm, p1) > - adj1[0]. - rewrite_header.max_l3_packet_bytes ? IP4_ERROR_MTU_EXCEEDED : - error1); + if (vlib_buffer_length_in_chain (vm, p0) > + adj0[0].rewrite_header.max_l3_packet_bytes) + { + error0 = IP4_ERROR_MTU_EXCEEDED; + next0 = IP4_REWRITE_NEXT_ICMP_ERROR; + icmp4_error_set_vnet_buffer + (p0, ICMP4_destination_unreachable, + ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, + 0); + } + if (vlib_buffer_length_in_chain (vm, p1) > + adj1[0].rewrite_header.max_l3_packet_bytes) + { + error1 = IP4_ERROR_MTU_EXCEEDED; + next1 = IP4_REWRITE_NEXT_ICMP_ERROR; + icmp4_error_set_vnet_buffer + (p1, ICMP4_destination_unreachable, + ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, + 0); + } if (is_mcast) { @@ -2290,9 +2300,16 @@ ip4_rewrite_inline (vlib_main_t * vm, vlib_buffer_length_in_chain (vm, p0) + rw_len0); /* Check MTU of outgoing interface. */ - error0 = (vlib_buffer_length_in_chain (vm, p0) - > adj0[0].rewrite_header.max_l3_packet_bytes - ? IP4_ERROR_MTU_EXCEEDED : error0); + if (vlib_buffer_length_in_chain (vm, p0) > + adj0[0].rewrite_header.max_l3_packet_bytes) + { + error0 = IP4_ERROR_MTU_EXCEEDED; + next0 = IP4_REWRITE_NEXT_ICMP_ERROR; + icmp4_error_set_vnet_buffer + (p0, ICMP4_destination_unreachable, + ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, + 0); + } if (is_mcast) { error0 = ((adj0[0].rewrite_header.sw_if_index == |