# HG changeset patch # User Anthony Doeraene <anthony.doeraene....@gmail.com> # Date 1723532143 -7200 # Tue Aug 13 08:55:43 2024 +0200 # Node ID d5b3c722c6796f5b163821b9a8402457420ade4a # Parent b72362042b52f378e18ff6d01ec533e447331214 HTTP: added MPTCP support.
Multipath TCP (MPTCP), standardized in RFC8684 [1], is a TCP extension that enables a TCP connection to use different paths. Multipath TCP has been used for several use cases. On smartphones, MPTCP enables seamless handovers between cellular and Wi-Fi networks while preserving Established connections. This use-case is what pushed Apple to use MPTCP since 2013 in multiple applications [2]. On dual-stack hosts, Multipath TCP enables the TCP connection to automatically use the best performing path, either IPv4 or IPv6. If one path fails, MPTCP automatically uses the other path. The benefit from MPTCP, both the client and the server have to support it. Multipath TCP is a backward-compatible TCP extension that is enabled by default on recent Linux distributions (Debian, Ubuntu, Redhat, ...). Multipath TCP is included in the Linux kernel since version 5.6 [3]. To use it on Linux, an application must explicitly enable it when creating the socket. No need to change anything else in the application. Even if MPTCP is supported by different OS, only Linux supports the `IPPROTO_MPTCP` protocol, which is why this feature is currently limited to Linux only. This patch adds a new parameter 'multipath' to the 'listen' directive in the HTTP module. This new parameter is only compatible with TCP if IPPROTO_MPTCP is defined, not with QUIC so far. Co-developed-by: Maxime Dourov <mu...@live.be> Link: https://www.rfc-editor.org/rfc/rfc8684.html [1] Link: https://www.tessares.net/apples-mptcp-story-so-far/ [2] Link: https://www.mptcp.dev [3] diff -r b72362042b52 -r d5b3c722c679 contrib/vim/syntax/nginx.vim --- a/contrib/vim/syntax/nginx.vim Tue Aug 13 08:50:15 2024 +0200 +++ b/contrib/vim/syntax/nginx.vim Tue Aug 13 08:55:43 2024 +0200 @@ -65,7 +65,7 @@ \ contained \ nextgroup=@ngxListenParams skipwhite skipempty syn keyword ngxListenOptions contained - \ default_server ssl quic proxy_protocol + \ default_server ssl quic proxy_protocol multipath \ setfib fastopen backlog rcvbuf sndbuf accept_filter deferred bind \ ipv6only reuseport so_keepalive \ nextgroup=@ngxListenParams skipwhite skipempty diff -r b72362042b52 -r d5b3c722c679 src/http/ngx_http.c --- a/src/http/ngx_http.c Tue Aug 13 08:50:15 2024 +0200 +++ b/src/http/ngx_http.c Tue Aug 13 08:55:43 2024 +0200 @@ -1845,6 +1845,7 @@ #endif ls->type = addr->opt.type; + ls->protocol = addr->opt.protocol; ls->backlog = addr->opt.backlog; ls->rcvbuf = addr->opt.rcvbuf; ls->sndbuf = addr->opt.sndbuf; diff -r b72362042b52 -r d5b3c722c679 src/http/ngx_http_core_module.c --- a/src/http/ngx_http_core_module.c Tue Aug 13 08:50:15 2024 +0200 +++ b/src/http/ngx_http_core_module.c Tue Aug 13 08:55:43 2024 +0200 @@ -4062,6 +4062,13 @@ } #endif +#ifdef IPPROTO_MPTCP + if (ngx_strcmp(value[n].data, "multipath") == 0) { + lsopt.protocol = IPPROTO_MPTCP; + continue; + } +#endif + if (ngx_strncmp(value[n].data, "backlog=", 8) == 0) { lsopt.backlog = ngx_atoi(value[n].data + 8, value[n].len - 8); lsopt.set = 1; @@ -4351,6 +4358,12 @@ } #endif +#ifdef IPPROTO_MPTCP + if (lsopt.protocol == IPPROTO_MPTCP) { + return "\"multipath\" parameter is incompatible with \"quic\""; + } +#endif + #if (NGX_HTTP_V2) if (lsopt.http2) { return "\"http2\" parameter is incompatible with \"quic\""; diff -r b72362042b52 -r d5b3c722c679 src/http/ngx_http_core_module.h --- a/src/http/ngx_http_core_module.h Tue Aug 13 08:50:15 2024 +0200 +++ b/src/http/ngx_http_core_module.h Tue Aug 13 08:55:43 2024 +0200 @@ -88,6 +88,7 @@ int rcvbuf; int sndbuf; int type; + int protocol; #if (NGX_HAVE_SETFIB) int setfib; #endif
