> -----Original Message-----
> From: Burakov, Anatoly
> Sent: Tuesday, November 6, 2018 10:54 AM
> To: Ananyev, Konstantin <konstantin.anan...@intel.com>; dev@dpdk.org
> Cc: sta...@dpdk.org; Hall, Ryan E <ryan.e.h...@intel.com>; Gutkin, Alexander
> V <alexander.v.gut...@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v2 2/2] ip_frag: use key length for key
> comparision
>
> On 05-Nov-18 12:18 PM, Konstantin Ananyev wrote:
> > Right now reassembly code relies on src_dst[] being all zeroes to
> > determine is it free/occupied entry in the fragments table.
> > This is suboptimal and error prone - user can crash DPDK ip_reassembly
> > app by something like the following scapy script:
> > x=Ether(src=...,dst=...)/IP(dst='0.0.0.0',src='0.0.0.0',id=0)/('X'*1000)
> > frags=fragment(x, fragsize=500)
> > sendp(frags, iface=...)
> > To overcome that issue and reduce overhead of
> > 'key invalidate' and 'key is empty' operations -
> > add key_len into keys comparision procedure.
> >
> > Fixes: 4f1a8f633862 ("ip_frag: add IPv6 reassembly")
> > Cc: sta...@dpdk.org
> >
> > Reported-by: Ryan E Hall <ryan.e.h...@intel.com>
> > Reported-by: Alexander V Gutkin <alexander.v.gut...@intel.com>
> > Signed-off-by: Konstantin Ananyev <konstantin.anan...@intel.com>
> > ---
>
>
>
> > @@ -44,9 +44,17 @@ struct ip_frag {
> >
> > /** @internal <src addr, dst_addr, id> to uniquely identify fragmented
> > datagram. */
> > struct ip_frag_key {
> > - uint64_t src_dst[4]; /**< src address, first 8 bytes used for IPv4
> > */
> > - uint32_t id; /**< dst address */
> > - uint32_t key_len; /**< src/dst key length */
> > + uint64_t src_dst[4];
> > + /**< src and dst address, only first 8 bytes used for IPv4 */
> > + RTE_STD_C11
> > + union {
> > + uint64_t id_key_len; /**< combined for easy fetch */
> > + __extension__
> > + struct {
> > + uint32_t id; /**< packet id */
> > + uint32_t key_len; /**< src/dst key length */
> > + };
> > + };
> > };
>
> Would that break ABI?
No, size and layout of the structure remains the same.
Konstantin
