From: Leslie Cheng <leslie.cheng5@xxxxxxxxx> This changeset introduces an `http.unixSocket` option so that users can proxy their git over HTTP remotes to a unix domain socket. In terms of why, since UDS are local and git already has a local protocol: some corporate environments use a UDS to proxy requests to internal resources (ie. source control), so this change would support those use-cases. This proxy can occasionally be necessary to attach MFA tokens or client certificates for CLI tools. The implementation leverages `--unix-socket` option [0] via the `CURLOPT_UNIX_SOCKET_PATH` flag available with libcurl [1]. `GIT_CURL_HAVE_CURLOPT_UNIX_SOCKET_PATH` and `NO_UNIX_SOCKETS` were kept separate so that we can spit out better error messages for users if git was compiled with `NO_UNIX_SOCKETS`. [0] https://curl.se/docs/manpage.html#--unix-socket [1] https://curl.se/libcurl/c/CURLOPT_UNIX_SOCKET_PATH.html Signed-off-by: Leslie Cheng <leslie@xxxxxx> --- Add unix domain socket support to HTTP transport Changes since v1: * Updated test to use Perl instead of nc to proxy between UDS and TCP socket; I chose not to split this out into a library since its use is hyper-specific and has a dependency on lib-httpd.sh Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1681%2Flcfyi%2Flcfyi%2Fadd-unix-socket-support-v2 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1681/lcfyi/lcfyi/add-unix-socket-support-v2 Pull-Request: https://github.com/git/git/pull/1681 Range-diff vs v1: 1: 3e531632329 ! 1: 2af5cc8089b Add unix domain socket support to HTTP transport. @@ Metadata Author: Leslie Cheng <leslie.cheng5@xxxxxxxxx> ## Commit message ## - Add unix domain socket support to HTTP transport. + Add unix domain socket support to HTTP transport This changeset introduces an `http.unixSocket` option so that users can proxy their git over HTTP remotes to a unix domain socket. In terms of @@ t/t5565-http-unix-domain-socket.sh (new) + test_done +} + -+UDS_TO_TCP_FIFO=uds_to_tcp -+TCP_TO_UDS_FIFO=tcp_to_uds -+UDS_PID= -+TCP_PID= ++if ! test_have_prereq PERL ++then ++ skip_all='skipping http-unix-socket tests; perl not available' ++ test_done ++fi ++ ++SOCKET_PROXY_PIDFILE="$(pwd)/proxy.pid" +UDS_SOCKET="$(pwd)/uds.sock" -+UNRESOLVABLE_ENDPOINT=http://localhost:4242 ++UNRESOLVABLE_ENDPOINT=http://unresolved + +start_proxy_unix_to_tcp() { -+ local socket_path="$UDS_SOCKET" -+ local host=127.0.0.1 -+ local port=$LIB_HTTPD_PORT -+ -+ rm -f "$UDS_TO_TCP_FIFO" -+ rm -f "$TCP_TO_UDS_FIFO" -+ rm -f "$socket_path" -+ mkfifo "$UDS_TO_TCP_FIFO" -+ mkfifo "$TCP_TO_UDS_FIFO" -+ nc -klU "$socket_path" <tcp_to_uds >uds_to_tcp & -+ UDS_PID=$! -+ -+ nc "$host" "$port" >tcp_to_uds <uds_to_tcp & -+ TCP_PID=$! -+ -+ test_atexit 'stop_proxy_unix_to_tcp' ++ test_atexit 'stop_proxy_unix_to_tcp' ++ ++ perl -Mstrict -MIO::Select -MIO::Socket::INET -MIO::Socket::UNIX -e ' ++ my $uds_path = $ARGV[0]; ++ my $host = $ARGV[1]; ++ my $port = $ARGV[2]; ++ my $pidfile = $ARGV[3]; ++ ++ open(my $fh, ">", $pidfile) or die "failed to create pidfile"; ++ print $fh "$$"; ++ close($fh); ++ ++ my $uds = IO::Socket::UNIX->new( ++ Local => $uds_path, ++ Type => SOCK_STREAM, ++ Listen => 5, ++ ) or die "failed to create unix domain socket"; ++ ++ while (my $conn = $uds->accept()) { ++ my $tcp_client = IO::Socket::INET->new( ++ PeerAddr => $host, ++ PeerPort => $port, ++ Proto => "tcp", ++ ) or die "failed to create TCP socket"; ++ ++ my $sel = IO::Select->new($conn, $tcp_client); ++ ++ while (my @ready = $sel->can_read(10)) { ++ foreach my $socket (@ready) { ++ my $other = ($socket == $conn) ? $tcp_client : $conn; ++ my $data; ++ my $bytes = $socket->sysread($data, 4096); ++ ++ if ($bytes) { ++ $other->syswrite($data, $bytes); ++ } else { ++ $socket->close(); ++ } ++ } ++ } ++ } ++ ' "$UDS_SOCKET" "127.0.0.1" "$LIB_HTTPD_PORT" "$SOCKET_PROXY_PIDFILE" & ++ SOCKET_PROXY_PID=$! +} + +stop_proxy_unix_to_tcp() { -+ kill "$UDS_PID" -+ kill "$TCP_PID" -+ rm -f "$UDS_TO_TCP_FIFO" -+ rm -f "$TCP_TO_UDS_FIFO" ++ kill -9 "$(cat "$SOCKET_PROXY_PIDFILE")" ++ rm -f "$SOCKET_PROXY_PIDFILE" ++ rm -f "$UDS_SOCKET" +} + +start_httpd @@ t/t5565-http-unix-domain-socket.sh (new) + +# sanity check that we can't clone normally +test_expect_success 'cloning without UDS fails' ' -+ test_must_fail git clone "$UNRESOLVABLE_ENDPOINT/smart/repo.git" clone ++ test_must_fail git clone "$UNRESOLVABLE_ENDPOINT/smart/repo.git" clone +' + +test_expect_success 'cloning with UDS succeeds' ' -+ test_when_finished "rm -rf clone" && ++ test_when_finished "rm -rf clone" && + test_config_global http.unixsocket "$UDS_SOCKET" && + git clone "$UNRESOLVABLE_ENDPOINT/smart/repo.git" clone +' + +test_expect_success 'cloning with a non-existent http proxy fails' ' -+ git clone $HTTPD_URL/smart/repo.git clone && -+ rm -rf clone && -+ test_config_global http.proxy 127.0.0.1:0 && -+ test_must_fail git clone $HTTPD_URL/smart/repo.git clone ++ git clone $HTTPD_URL/smart/repo.git clone && ++ rm -rf clone && ++ test_config_global http.proxy 127.0.0.1:0 && ++ test_must_fail git clone $HTTPD_URL/smart/repo.git clone +' + +test_expect_success 'UDS socket takes precedence over http proxy' ' -+ test_when_finished "rm -rf clone" && -+ test_config_global http.proxy 127.0.0.1:0 && -+ test_config_global http.unixsocket "$UDS_SOCKET" && -+ git clone $HTTPD_URL/smart/repo.git clone ++ test_when_finished "rm -rf clone" && ++ test_config_global http.proxy 127.0.0.1:0 && ++ test_config_global http.unixsocket "$UDS_SOCKET" && ++ git clone $HTTPD_URL/smart/repo.git clone +' + +test_done Documentation/config/http.txt | 5 ++ git-curl-compat.h | 7 ++ http.c | 23 ++++++ t/t5565-http-unix-domain-socket.sh | 109 +++++++++++++++++++++++++++++ 4 files changed, 144 insertions(+) create mode 100755 t/t5565-http-unix-domain-socket.sh diff --git a/Documentation/config/http.txt b/Documentation/config/http.txt index 2d4e0c9b869..bf48cbd599a 100644 --- a/Documentation/config/http.txt +++ b/Documentation/config/http.txt @@ -277,6 +277,11 @@ http.followRedirects:: the base for the follow-up requests, this is generally sufficient. The default is `initial`. +http.unixSocket:: + Connect through this Unix domain socket via HTTP, instead of using the + network. If set, this config takes precendence over `http.proxy` and + is incompatible with the proxy options (see `curl(1)`). + http.<url>.*:: Any of the http.* options above can be applied selectively to some URLs. For a config key to match a URL, each element of the config key is diff --git a/git-curl-compat.h b/git-curl-compat.h index fd96b3cdffd..f0f3bec0e17 100644 --- a/git-curl-compat.h +++ b/git-curl-compat.h @@ -74,6 +74,13 @@ #define GIT_CURL_HAVE_CURLE_SSL_PINNEDPUBKEYNOTMATCH 1 #endif +/** + * CURLOPT_UNIX_SOCKET_PATH was added in 7.40.0, released in January 2015. + */ +#if LIBCURL_VERSION_NUM >= 0x074000 +#define GIT_CURL_HAVE_CURLOPT_UNIX_SOCKET_PATH 1 +#endif + /** * CURL_HTTP_VERSION_2 was added in 7.43.0, released in June 2015. * diff --git a/http.c b/http.c index e73b136e589..8cfdcaeac82 100644 --- a/http.c +++ b/http.c @@ -79,6 +79,9 @@ static const char *http_proxy_ssl_ca_info; static struct credential proxy_cert_auth = CREDENTIAL_INIT; static int proxy_ssl_cert_password_required; +#if defined(GIT_CURL_HAVE_CURLOPT_UNIX_SOCKET_PATH) && !defined(NO_UNIX_SOCKETS) +static const char *curl_unix_socket_path; +#endif static struct { const char *name; long curlauth_param; @@ -455,6 +458,20 @@ static int http_options(const char *var, const char *value, return 0; } + if (!strcmp("http.unixsocket", var)) { +#ifdef GIT_CURL_HAVE_CURLOPT_UNIX_SOCKET_PATH +#ifndef NO_UNIX_SOCKETS + return git_config_string(&curl_unix_socket_path, var, value); +#else + warning(_("Unix socket support unavailable in this build of Git")); + return 0; +#endif +#else + warning(_("Unix socket support is not supported with cURL < 7.40.0")); + return 0; +#endif + } + if (!strcmp("http.cookiefile", var)) return git_config_pathname(&curl_cookie_file, var, value); if (!strcmp("http.savecookies", var)) { @@ -1203,6 +1220,12 @@ static CURL *get_curl_handle(void) } init_curl_proxy_auth(result); +#if defined(GIT_CURL_HAVE_CURLOPT_UNIX_SOCKET_PATH) && !defined(NO_UNIX_SOCKETS) + if (curl_unix_socket_path) { + curl_easy_setopt(result, CURLOPT_UNIX_SOCKET_PATH, curl_unix_socket_path); + } +#endif + set_curl_keepalive(result); return result; diff --git a/t/t5565-http-unix-domain-socket.sh b/t/t5565-http-unix-domain-socket.sh new file mode 100755 index 00000000000..2f9c53ab14f --- /dev/null +++ b/t/t5565-http-unix-domain-socket.sh @@ -0,0 +1,109 @@ +#!/bin/sh + +test_description="test fetching through http via unix domain socket" + +. ./test-lib.sh +. "$TEST_DIRECTORY"/lib-httpd.sh + +test -z "$NO_UNIX_SOCKETS" || { + skip_all='skipping http-unix-socket tests, unix sockets not available' + test_done +} + +if ! test_have_prereq PERL +then + skip_all='skipping http-unix-socket tests; perl not available' + test_done +fi + +SOCKET_PROXY_PIDFILE="$(pwd)/proxy.pid" +UDS_SOCKET="$(pwd)/uds.sock" +UNRESOLVABLE_ENDPOINT=http://unresolved + +start_proxy_unix_to_tcp() { + test_atexit 'stop_proxy_unix_to_tcp' + + perl -Mstrict -MIO::Select -MIO::Socket::INET -MIO::Socket::UNIX -e ' + my $uds_path = $ARGV[0]; + my $host = $ARGV[1]; + my $port = $ARGV[2]; + my $pidfile = $ARGV[3]; + + open(my $fh, ">", $pidfile) or die "failed to create pidfile"; + print $fh "$$"; + close($fh); + + my $uds = IO::Socket::UNIX->new( + Local => $uds_path, + Type => SOCK_STREAM, + Listen => 5, + ) or die "failed to create unix domain socket"; + + while (my $conn = $uds->accept()) { + my $tcp_client = IO::Socket::INET->new( + PeerAddr => $host, + PeerPort => $port, + Proto => "tcp", + ) or die "failed to create TCP socket"; + + my $sel = IO::Select->new($conn, $tcp_client); + + while (my @ready = $sel->can_read(10)) { + foreach my $socket (@ready) { + my $other = ($socket == $conn) ? $tcp_client : $conn; + my $data; + my $bytes = $socket->sysread($data, 4096); + + if ($bytes) { + $other->syswrite($data, $bytes); + } else { + $socket->close(); + } + } + } + } + ' "$UDS_SOCKET" "127.0.0.1" "$LIB_HTTPD_PORT" "$SOCKET_PROXY_PIDFILE" & + SOCKET_PROXY_PID=$! +} + +stop_proxy_unix_to_tcp() { + kill -9 "$(cat "$SOCKET_PROXY_PIDFILE")" + rm -f "$SOCKET_PROXY_PIDFILE" + rm -f "$UDS_SOCKET" +} + +start_httpd +start_proxy_unix_to_tcp + +test_expect_success 'setup repository' ' + test_commit foo && + git init --bare "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" && + git push --mirror "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" +' + +# sanity check that we can't clone normally +test_expect_success 'cloning without UDS fails' ' + test_must_fail git clone "$UNRESOLVABLE_ENDPOINT/smart/repo.git" clone +' + +test_expect_success 'cloning with UDS succeeds' ' + test_when_finished "rm -rf clone" && + test_config_global http.unixsocket "$UDS_SOCKET" && + git clone "$UNRESOLVABLE_ENDPOINT/smart/repo.git" clone +' + +test_expect_success 'cloning with a non-existent http proxy fails' ' + git clone $HTTPD_URL/smart/repo.git clone && + rm -rf clone && + test_config_global http.proxy 127.0.0.1:0 && + test_must_fail git clone $HTTPD_URL/smart/repo.git clone +' + +test_expect_success 'UDS socket takes precedence over http proxy' ' + test_when_finished "rm -rf clone" && + test_config_global http.proxy 127.0.0.1:0 && + test_config_global http.unixsocket "$UDS_SOCKET" && + git clone $HTTPD_URL/smart/repo.git clone +' + +test_done base-commit: 3e0d3cd5c7def4808247caf168e17f2bbf47892b -- gitgitgadget
