VPP-1283: IPv6 PMTU missing MTU value in ICMP6 message.
Fix GRE/IPv6 setting of ip->payload_length (which has never worked).
Change-Id: Ie68f1cc7bbb70489d6ec97356132c783f2345e1e
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/src/vnet/gre/gre.c b/src/vnet/gre/gre.c
index 0b8d2cc..e82befe 100644
--- a/src/vnet/gre/gre.c
+++ b/src/vnet/gre/gre.c
@@ -292,8 +292,8 @@
/* Fixup the payload length field in the GRE tunnel encap that was applied
* at the midchain node */
ip0->payload_length =
- clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0))
- - sizeof (*ip0);
+ clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
+ sizeof (*ip0));
}
void
diff --git a/src/vnet/ip/icmp6.c b/src/vnet/ip/icmp6.c
index fd5d0ec..6ebdef4 100644
--- a/src/vnet/ip/icmp6.c
+++ b/src/vnet/ip/icmp6.c
@@ -526,13 +526,15 @@
b->current_length = 0;
}
}
- p0->current_length =
- p0->current_length > 1280 ? 1280 : p0->current_length;
/* Add IP header and ICMPv6 header including a 4 byte data field */
vlib_buffer_advance (p0,
-sizeof (ip6_header_t) -
sizeof (icmp46_header_t) - 4);
+
+ p0->current_length =
+ p0->current_length > 1280 ? 1280 : p0->current_length;
+
out_ip0 = vlib_buffer_get_current (p0);
icmp0 = (icmp46_header_t *) & out_ip0[1];
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index c45b65f..f4c51e2 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -1561,6 +1561,19 @@
*/
#define IP6_MCAST_ADDR_MASK 0xffffffff
+always_inline void
+ip6_mtu_check (vlib_buffer_t * b, u16 packet_bytes,
+ u16 adj_packet_bytes, u32 * next, u32 * error)
+{
+ if (adj_packet_bytes >= 1280 && packet_bytes > adj_packet_bytes)
+ {
+ *error = IP6_ERROR_MTU_EXCEEDED;
+ icmp6_error_set_vnet_buffer (b, ICMP6_packet_too_big, 0,
+ adj_packet_bytes);
+ *next = IP6_REWRITE_NEXT_ICMP_ERROR;
+ }
+}
+
always_inline uword
ip6_rewrite_inline (vlib_main_t * vm,
vlib_node_runtime_t * node,
@@ -1706,16 +1719,14 @@
}
/* Check MTU of outgoing interface. */
- error0 =
- (vlib_buffer_length_in_chain (vm, p0) >
- adj0[0].
- rewrite_header.max_l3_packet_bytes ? IP6_ERROR_MTU_EXCEEDED :
- error0);
- error1 =
- (vlib_buffer_length_in_chain (vm, p1) >
- adj1[0].
- rewrite_header.max_l3_packet_bytes ? IP6_ERROR_MTU_EXCEEDED :
- error1);
+ ip6_mtu_check (p0, clib_net_to_host_u16 (ip0->payload_length) +
+ sizeof (ip6_header_t),
+ adj0[0].rewrite_header.max_l3_packet_bytes,
+ &next0, &error0);
+ ip6_mtu_check (p1, clib_net_to_host_u16 (ip1->payload_length) +
+ sizeof (ip6_header_t),
+ adj1[0].rewrite_header.max_l3_packet_bytes,
+ &next1, &error1);
/* Don't adjust the buffer for hop count issue; icmp-error node
* wants to see the IP headerr */
@@ -1849,14 +1860,13 @@
}
/* Check MTU of outgoing interface. */
- error0 =
- (vlib_buffer_length_in_chain (vm, p0) >
- adj0[0].
- rewrite_header.max_l3_packet_bytes ? IP6_ERROR_MTU_EXCEEDED :
- error0);
+ ip6_mtu_check (p0, clib_net_to_host_u16 (ip0->payload_length) +
+ sizeof (ip6_header_t),
+ adj0[0].rewrite_header.max_l3_packet_bytes,
+ &next0, &error0);
/* Don't adjust the buffer for hop count issue; icmp-error node
- * wants to see the IP headerr */
+ * wants to see the IP header */
if (PREDICT_TRUE (error0 == IP6_ERROR_NONE))
{
p0->current_data -= rw_len0;