| Message ID | 20210811131523.6339-1-fw@strlen.de (mailing list archive) |
|---|---|
| Headers | show |
| Series | mptcp: add SOL_MPTCP getsockopt support | expand |
Hello Florian, On Wed, 2021-08-11 at 15:15 +0200, Florian Westphal wrote: > This adds the MPTCP_INFO, MPTCP_TCPINFO and MPTCP_SUBFLOW_ADDRS > mptcp getsockopt optnames. > > MPTCP_INFO exposes the mptcp_info struct as an alternative to the > existing netlink diag interface. > > MPTCP_TCPINFO exposes the tcp_info struct. > Unlike SOL_TCP/TCP_INFO, this returns one struct for each active > subflow. > > MPTCP_SUBFLOW_ADDRS allows userspace to discover the ip addresses/ports > used by the local and remote endpoints, one for each active tcp subflow. > > MPTCP_TCPINFO and MPTCP_SUBFLOW_ADDRS share the same meta-header that > needs to be pre-filled by userspace with the size of the data structures > it expects. This is done to allow extension of the involved structs > later on, without breaking backwards compatibility. > > The meta-structure can also be used to discover the required space > to obtain all information, as kernel will fill in the number of > active subflows even if there is not enough room for the requested info > itself. > > More information is available in the individual patches. > Last patch adds test cases for the three optnames. > > Florian Westphal (5): > mptcp: add new mptcp_fill_diag helper > mptcp: add MPTCP_INFO getsockopt > mptcp: add MPTCP_TCPINFO getsockopt support > mptcp: add MPTCP_SUBFLOW_ADDRS getsockopt support > selftests: mptcp: add mptcp getsockopt test cases > > include/linux/socket.h | 1 + > include/net/mptcp.h | 4 + > include/uapi/linux/mptcp.h | 29 + > net/mptcp/mptcp_diag.c | 26 +- > net/mptcp/sockopt.c | 258 +++++++++ > tools/testing/selftests/net/mptcp/Makefile | 4 +- > .../selftests/net/mptcp/mptcp_sockopt.c | 545 ++++++++++++++++++ > .../selftests/net/mptcp/mptcp_sockopt.sh | 31 +- > 8 files changed, 869 insertions(+), 29 deletions(-) > create mode 100644 tools/testing/selftests/net/mptcp/mptcp_sockopt.c The patches LGTM! I have just a couple of minor curiosity. In some helper the argument that carries the option length from user space is named '_u_optlen', any special reason for that? Encoding the argument attribute into the user name looks really win32 style from the early 2000, afaik ;))) [no offense intended!!!] I don't see how the mptcp_subflow_addrs is going to change/increase the size with time... do you have some possible ideas/guess? Anyhow, Acked-by: Paolo Abeni <pabeni@redhat.com>
Paolo Abeni <pabeni@redhat.com> wrote: > > 8 files changed, 869 insertions(+), 29 deletions(-) > > create mode 100644 tools/testing/selftests/net/mptcp/mptcp_sockopt.c > > The patches LGTM! I have just a couple of minor curiosity. > > In some helper the argument that carries the option length from user > space is named '_u_optlen', any special reason for that? Encoding the > argument attribute into the user name looks really win32 style from the > early 2000, afaik ;))) [no offense intended!!!] Ok, I'll rename it to 'int __user *optlen' in v2. > I don't see how the mptcp_subflow_addrs is going to change/increase the > size with time... do you have some possible ideas/guess? No idea. IPv8? I added struct sockaddr_storage into the union so it will hopefully be enough but who knows, this API might well live on for decades and I'd rather have a small back door that allows to increase this if needed.