[PATCH] http: add a config to limit the connection time

@@ -300,6 +300,13 @@ for most push problems, but can increase memory consumption
 significantly since the entire buffer is allocated even for small
 pushes.
 
+http.connectTimeoutMS::
+	Maximum time in milliseconds that you allow the connection phase
+	to take. The connection phase includes DNS lookup and subsequent
+	TCP, TLS or QUIC handshakes.
+	Can be overridden by the `GIT_HTTP_CONNECT_TIMEOUT_MS`
+	environment variable.
+
 http.lowSpeedLimit::
 http.lowSpeedTime::
 	If the HTTP transfer speed, in bytes per second, is less than

@@ -68,6 +68,7 @@ static char *ssl_capath;
 static char *curl_no_proxy;
 static char *ssl_pinnedkey;
 static char *ssl_cainfo;
+static long curl_connect_timeout_ms = -1;
 static long curl_low_speed_limit = -1;
 static long curl_low_speed_time = -1;
 static int curl_ftp_no_epsv;

@@ -450,6 +451,10 @@ static int http_options(const char *var, const char *value,
 		max_requests = git_config_int(var, value, ctx->kvi);
 		return 0;
 	}
+	if (!strcmp("http.connecttimeoutms", var)) {
+		curl_connect_timeout_ms = git_config_int(var, value, ctx->kvi);
+		return 0;
+	}
 	if (!strcmp("http.lowspeedlimit", var)) {
 		curl_low_speed_limit = git_config_int(var, value, ctx->kvi);
 		return 0;

@@ -1215,6 +1220,10 @@ static CURL *get_curl_handle(void)
 			curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, http_proxy_ssl_ca_info);
 	}
 
+	if (curl_connect_timeout_ms > 0)
+		curl_easy_setopt(result, CURLOPT_CONNECTTIMEOUT_MS,
+				 curl_connect_timeout_ms);
+
 	if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 		curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 				 curl_low_speed_limit);

@@ -1474,6 +1483,8 @@ void http_init(struct remote *remote, const char *url, int proactive_auth)
 
 	set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 
+	set_long_from_env(&curl_connect_timeout_ms, "GIT_HTTP_CONNECT_TIMEOUT_MS");
+
 	set_long_from_env(&curl_low_speed_limit, "GIT_HTTP_LOW_SPEED_LIMIT");
 	set_long_from_env(&curl_low_speed_time, "GIT_HTTP_LOW_SPEED_TIME");
 

@@ -724,6 +724,7 @@ integration_tests = [
   't5582-fetch-negative-refspec.sh',
   't5583-push-branches.sh',
   't5584-http-429-retry.sh',
+  't5585-http-connect-timeout.sh',
   't5600-clone-fail-cleanup.sh',
   't5601-clone.sh',
   't5602-clone-remote-exec.sh',

@@ -0,0 +1,60 @@
+#!/bin/sh
+
+test_description='test http.connecttimeoutms and GIT_HTTP_CONNECT_TIMEOUT_MS'
+
+. ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-httpd.sh
+start_httpd
+
+test_expect_success 'setup repository' '
+	test_commit initial &&
+	git clone --bare . "$HTTPD_DOCUMENT_ROOT_PATH/repo.git" &&
+	git --git-dir="$HTTPD_DOCUMENT_ROOT_PATH/repo.git" config http.receivepack true
+'
+
+test_expect_success 'http.connecttimeoutms accepts a positive integer via config' '
+	test_config http.connecttimeoutms 5000 &&
+	git ls-remote "$HTTPD_URL/smart/repo.git" >output &&
+	test_grep "refs/heads/" output
+'
+
+test_expect_success 'http.connecttimeoutms=0 is accepted (disables the option)' '
+	test_config http.connecttimeoutms 0 &&
+	git ls-remote "$HTTPD_URL/smart/repo.git" >output &&
+	test_grep "refs/heads/" output
+'
+
+test_expect_success 'GIT_HTTP_CONNECT_TIMEOUT_MS env var is accepted' '
+	GIT_HTTP_CONNECT_TIMEOUT_MS=5000 \
+		git ls-remote "$HTTPD_URL/smart/repo.git" >output 2>err &&
+	test_grep "refs/heads/" output &&
+	test_grep ! . err
+'
+
+test_expect_success 'http.connecttimeoutms rejects non-numeric config value' '
+	test_config http.connecttimeoutms not-a-number &&
+	test_must_fail git ls-remote "$HTTPD_URL/smart/repo.git" 2>err &&
+	test_grep "bad numeric config value .not-a-number. for .http\.connecttimeoutms." err
+'
+
+test_expect_success 'http.connecttimeoutms rejects empty config value' '
+	test_config http.connecttimeoutms "" &&
+	test_must_fail git ls-remote "$HTTPD_URL/smart/repo.git" 2>err &&
+	test_grep "bad numeric config value" err
+'
+
+test_expect_success 'GIT_HTTP_CONNECT_TIMEOUT_MS warns on non-numeric value but succeeds' '
+	GIT_HTTP_CONNECT_TIMEOUT_MS=not-a-number \
+		git ls-remote "$HTTPD_URL/smart/repo.git" >output 2>err &&
+	test_grep "refs/heads/" output &&
+	test_grep "failed to parse GIT_HTTP_CONNECT_TIMEOUT_MS" err
+'
+
+test_expect_success 'GIT_HTTP_CONNECT_TIMEOUT_MS warns on empty value but succeeds' '
+	GIT_HTTP_CONNECT_TIMEOUT_MS= \
+		git ls-remote "$HTTPD_URL/smart/repo.git" >output 2>err &&
+	test_grep "refs/heads/" output &&
+	test_grep "failed to parse GIT_HTTP_CONNECT_TIMEOUT_MS" err
+'
+
+test_done