Re: [MPTCP] [PATCH v2 00/25] TCP Extra-option framework for TCP-MD5 and SMC

On Wed, 29 Nov 2017, Christoph Paasch wrote: > On 29/11/17 - 12:56:17, Christoph Paasch wrote: > > Oh, and one more thing. > > > > tcp_extra_options_* is quite long, and function-names are really long, > > bringing us often close to the 80-char "limit". > > > > What do you think of abbreviating it to "tcp_eo" or "teo" or something like > > that? > > tcp_xopt_* ? :) I don't have a strong preference, but tcp_extopt_* maps a little better to "extra" or "extended" options (in my mind, anyway).

Mat > > > > > > Christoph > > > > On 28/11/17 - 17:15:54, Mat Martineau wrote: > > > > > > Christoph - > > > > > > On Mon, 27 Nov 2017, Christoph Paasch wrote: > > > > > > > Finally, the second version of this patch-set. > > > > > > > > At netdev I talked about this with Eric, and he is looking forward to see > > > > TCP-MD5 get out of the hot TCP data-path. He was planning to avoid TCP-MD5 > > > > with static jump-labels and also move TCP-MD5 in a separate file. > > > > > > Good to hear that he's interested. > > > > > > > > > > > > > > > There are quite a few changes in this new set. I extended much more the > > > > extra-option framework. Making the list on a per-socket basis in the > > > > request-socket, tcp-socket and time-wait-socket. This eliminates the need > > > > for RCU-locking. See patch "tcp_extra_options: Make extra-option list per-socket" > > > > > > > > I also added callbacks for response_write/prepare that can be called from the > > > > tcp_v4_send_ack/rst, and v6 counterparts. This is needed because in these > > > > code-paths the skb and sk have entirely different semantics. > > > > > > > > Finally, in the input-path I added a check-callback and a post-process callback. > > > > > > > > This is needed because after parsing the option in tcp_parse_options() we also > > > > need to act on them. The actions can be either before any other checks (e.g., > > > > as is the case for TCP_MD5, because we want to drop segments) or after the > > > > validity checks (e.g., as is needed for SMC). > > > > > > > > And I also opted SMC into the new framework. > > > > > > > > And, I made the TCP-MD5 input code-path use the framework. > > > > > > All of these seem like the right way to go. Nice to have two users of the > > > framework already. > > > > > > > > > > > > > > > There are still a few things that I need to double-check, notably > > > > sk_nocaps_add() in TCP_MD5. > > > > > > > > And, I need to test ;-) > > > > > > Yeah, that testing :) > > > > > > > > > > > But I would like to have some early feedback already - especially on the patches > > > > prefixed with "tcp_extra_options". If they look good, I can merge them into Mat's > > > > patch, which will simplify my patch-juggling. > > > > > > I have a few comments, but no major structural changes. I'll reply to the > > > individual patches where needed. > > > > > > > I want to get this patch-set out to netdev as an RFC as quickly as possible, so > > > > that we can make some progress. > > > > > > Agreed! > > > > > > Mat > > > > > > > > > > > > > > > > > > Christoph Paasch (24): > > > > tcp: Write options after the header has been fully done > > > > tcp: Pass sock to tcp_options_write instead of tcp_sock > > > > tcp: Pass skb in tcp_options_write > > > > tcp: Allow tcp_fast_parse_options to drop segments > > > > tcp: Make smc_parse_options return 1 on success > > > > tcp_md5: Don't pass along md5-key > > > > tcp_md5: Detect key inside tcp_v4_send_ack instead of passing it as an > > > > argument > > > > tcp_md5: Detect key inside tcp_v6_send_response instead of passing it > > > > as an argument > > > > tcp_extra_options: Extend tcp_extra_options_write > > > > tcp_extra_options: Make extra-option list per-socket > > > > tcp_extra_options: Export module fixes > > > > tcp_extra_options: Add response_prepare callback > > > > tcp_extra_options: Check static branch before _parse > > > > tcp_extra_options: Skip fast-path when extra-options are present > > > > tcp_extra_options: Pass sk to tcp_parse_options instead of tp > > > > tcp_extra_options: Add check-callback right after parsing the option > > > > tcp_extra_options: Allow to parse experimental options > > > > tcp_extra_options: Add post_process callback > > > > tcp_smc: Make SMC use TCP extra-option framework > > > > tcp_md5: Check for TCP_MD5 after TCP Timestamps in > > > > tcp_established_options > > > > tcp_md5: Move TCP-MD5 code out of TCP itself > > > > tcp_md5: Use tcp_extra_options in output path > > > > tcp_md5: Cleanup TCP-code > > > > tcp_md5: Use TCP extra-options on the input path > > > > > > > > Mat Martineau (1): > > > > tcp: Register handlers for extra TCP options > > > > > > > > drivers/infiniband/hw/cxgb4/cm.c | 2 +- > > > > include/linux/inet_diag.h | 1 + > > > > include/linux/tcp.h | 41 +- > > > > include/linux/tcp_md5.h | 38 ++ > > > > include/net/inet_sock.h | 3 +- > > > > include/net/tcp.h | 216 ++++--- > > > > net/ipv4/Makefile | 1 + > > > > net/ipv4/syncookies.c | 6 +- > > > > net/ipv4/tcp.c | 372 ++++++++--- > > > > net/ipv4/tcp_diag.c | 81 +-- > > > > net/ipv4/tcp_input.c | 134 ++-- > > > > net/ipv4/tcp_ipv4.c | 553 ++-------------- > > > > net/ipv4/tcp_md5.c | 1317 ++++++++++++++++++++++++++++++++++++++ > > > > net/ipv4/tcp_minisocks.c | 76 +-- > > > > net/ipv4/tcp_output.c | 183 +----- > > > > net/ipv6/syncookies.c | 6 +- > > > > net/ipv6/tcp_ipv6.c | 386 ++--------- > > > > net/smc/af_smc.c | 170 ++++- > > > > 18 files changed, 2148 insertions(+), 1438 deletions(-) > > > > create mode 100644 include/linux/tcp_md5.h > > > > create mode 100644 net/ipv4/tcp_md5.c > > > > > > > > -- > > > > 2.15.0 > > > > > > > > > > > > > > -- > > > Mat Martineau > > > Intel OTC > > _______________________________________________ > > mptcp mailing list > > mptcp(a)lists.01.org > > https://lists.01.org/mailman/listinfo/mptcp > -- Mat Martineau Intel OTC