ip: Fixes for IPv6 and MPLS fragmentation
Type: fix
- IPv6 fragmentation did not work if the packet spaneed multiple buffers, because the 'len' calculation to did max out at the size of a buffer
- IPv6 fragmentation did not work when the l2unfragmentable size was non-zero, it was not used in the correct places
- IPv6oMPLS fragmentation would fragment all IPv6, it should do so only for link local
- IPv6oMPLS should send back TooBig ICMP6 for non locally generated
Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: Ie8f02cdfdd7b7e8474e62b6d0acda8f20c371184
diff --git a/src/vnet/ip/ip_frag.c b/src/vnet/ip/ip_frag.c
index b9bc90d..9c223c3 100644
--- a/src/vnet/ip/ip_frag.c
+++ b/src/vnet/ip/ip_frag.c
@@ -25,10 +25,10 @@
typedef struct
{
- u8 ipv6;
u16 mtu;
u8 next;
u16 n_fragments;
+ u16 pkt_size;
} ip_frag_trace_t;
static u8 *
@@ -37,8 +37,8 @@
CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
ip_frag_trace_t *t = va_arg (*args, ip_frag_trace_t *);
- s = format (s, "IPv%s mtu: %u fragments: %u next: %d",
- t->ipv6 ? "6" : "4", t->mtu, t->n_fragments, t->next);
+ s = format (s, "mtu: %u pkt-size: %u fragments: %u next: %d", t->mtu,
+ t->pkt_size, t->n_fragments, t->next);
return s;
}
@@ -286,7 +286,7 @@
ip_frag_trace_t *tr =
vlib_add_trace (vm, node, p0, sizeof (*tr));
tr->mtu = mtu;
- tr->ipv6 = is_ip6 ? 1 : 0;
+ tr->pkt_size = vlib_buffer_length_in_chain (vm, p0);
tr->n_fragments = vec_len (buffer);
tr->next = vnet_buffer (p0)->ip_frag.next_index;
}
@@ -385,13 +385,17 @@
ip6_header_t *ip6;
u16 len, max, rem, ip_frag_id;
u8 *org_from_packet;
+ u16 head_bytes;
from_b = vlib_get_buffer (vm, from_bi);
org_from_packet = vlib_buffer_get_current (from_b);
ip6 = vlib_buffer_get_current (from_b) + l2unfragmentablesize;
+ head_bytes =
+ (sizeof (ip6_header_t) + sizeof (ip6_frag_hdr_t) + l2unfragmentablesize);
rem = clib_net_to_host_u16 (ip6->payload_length);
- max = (mtu - sizeof (ip6_header_t) - sizeof (ip6_frag_hdr_t)) & ~0x7; // TODO: Is max correct??
+ max = (clib_min (mtu, vlib_buffer_get_default_data_size (vm)) - head_bytes) &
+ ~0x7;
if (rem >
(vlib_buffer_length_in_chain (vm, from_b) - sizeof (ip6_header_t)))
@@ -423,9 +427,7 @@
ip6_frag_hdr_t *to_frag_hdr;
u8 *to_data;
- len =
- (rem >
- (mtu - sizeof (ip6_header_t) - sizeof (ip6_frag_hdr_t)) ? max : rem);
+ len = (rem > max ? max : rem);
if (len != rem) /* Last fragment does not need to divisible by 8 */
len &= ~0x7;
if ((to_b = frag_buffer_alloc (org_from_b, &to_bi)) == 0)
@@ -438,7 +440,7 @@
/* Copy ip6 header */
clib_memcpy_fast (to_b->data, org_from_packet,
l2unfragmentablesize + sizeof (ip6_header_t));
- to_ip6 = vlib_buffer_get_current (to_b);
+ to_ip6 = vlib_buffer_get_current (to_b) + l2unfragmentablesize;
to_frag_hdr = (ip6_frag_hdr_t *) (to_ip6 + 1);
to_data = (void *) (to_frag_hdr + 1);
@@ -484,8 +486,7 @@
to_ptr += bytes_to_copy;
}
- to_b->current_length =
- len + sizeof (ip6_header_t) + sizeof (ip6_frag_hdr_t);
+ to_b->current_length = len + head_bytes;
to_ip6->payload_length =
clib_host_to_net_u16 (len + sizeof (ip6_frag_hdr_t));
to_ip6->protocol = IP_PROTOCOL_IPV6_FRAGMENTATION;