From ec5371e3e31b7860d6b3996fd10420566a4377f2 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Fri, 4 Mar 2022 11:45:41 +0000 Subject: 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 Change-Id: Ie8f02cdfdd7b7e8474e62b6d0acda8f20c371184 --- src/vnet/ip/ip_frag.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'src/vnet/ip/ip_frag.c') diff --git a/src/vnet/ip/ip_frag.c b/src/vnet/ip/ip_frag.c index b9bc90dcc11..9c223c3d0ae 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 @@ format_ip_frag_trace (u8 * s, va_list * args) 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 @@ frag_node_inline (vlib_main_t * vm, vlib_node_runtime_t * node, 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_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u16 mtu, 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_do_fragment (vlib_main_t * vm, u32 from_bi, u16 mtu, 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 @@ ip6_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u16 mtu, /* 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 @@ ip6_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u16 mtu, 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; -- cgit 1.2.3-korg