--- /dev/null
+<?xml version="1.0" encoding="US-ASCII"?>
+<testcase>
+<info>
+<keywords>
+HTTP
+HTTP GET
+HTTP proxy
+HTTP proxy auth
+</keywords>
+</info>
+
+# Server-side
+<reply>
+
+# this is returned first since we get no proxy-auth
+<data crlf="headers" nocheck="yes">
+HTTP/1.1 407 Authorization Required to proxy me my dear
+Proxy-Authenticate: Digest realm="weirdorealm", nonce="12345"
+Content-Length: 33
+
+And you should ignore this data.
+</data>
+
+</reply>
+
+# Client-side
+<client>
+<server>
+http
+</server>
+# tool is what to use instead of 'curl'
+<tool>
+lib%TESTNUMBER
+</tool>
+<features>
+proxy
+</features>
+<name>
+HTTP proxy with auth, change proxy, clear auth
+</name>
+<command>
+%HOSTIP %HTTPPORT
+</command>
+</client>
+
+# Verify data after the test has been "shot"
+<verify>
+<protocol crlf="headers">
+GET http://example.com/ HTTP/1.1
+Host: example.com
+Proxy-Authorization: Basic %b64[victim:secret]b64%
+Accept: */*
+Proxy-Connection: Keep-Alive
+
+GET http://example.com/ HTTP/1.1
+Host: example.com
+Accept: */*
+Proxy-Connection: Keep-Alive
+
+</protocol>
+
+</verify>
+</testcase>
--- /dev/null
+/***************************************************************************
+ * _ _ ____ _
+ * Project ___| | | | _ \| |
+ * / __| | | | |_) | |
+ * | (__| |_| | _ <| |___
+ * \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * SPDX-License-Identifier: curl
+ *
+ ***************************************************************************/
+/*
+ * URL = host
+ * arg2 = port
+ */
+
+#include "first.h"
+
+/* this is meant to pick up the proxy from the environment variable */
+static CURLcode init1648(CURL *curl, const char *url, const char *proxy)
+{
+ CURLcode result = CURLE_OK;
+
+ res_easy_setopt(curl, CURLOPT_URL, url);
+ if(result)
+ goto init_failed;
+
+ res_easy_setopt(curl, CURLOPT_PROXY, proxy);
+ if(result)
+ goto init_failed;
+
+ res_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
+ if(result)
+ goto init_failed;
+
+ return CURLE_OK; /* success */
+
+init_failed:
+ return result; /* failure */
+}
+
+static CURLcode run1648(CURL *curl, const char *url, const char *userpwd)
+{
+ CURLcode result = CURLE_OK;
+
+ result = init1648(curl, url, userpwd);
+ if(result)
+ return result;
+
+ return curl_easy_perform(curl);
+}
+
+#define GET_THIS "http://example.com/"
+
+/*
+ * First get the URL over 'firstproxy' with auth.
+ * Then clear the auth and get the URL again over 'secondproxy'.
+ */
+static CURLcode test_lib1648(const char *hostip)
+{
+ CURLcode result = CURLE_OK;
+ CURL *curl = NULL;
+ struct curl_slist *host = NULL;
+ struct curl_slist *host2 = NULL;
+ char proxy1_resolve[128];
+ char proxy2_resolve[128];
+ char proxy1_connect[128];
+ char proxy2_connect[128];
+
+ curl_msnprintf(proxy1_resolve, sizeof(proxy1_resolve),
+ "firstproxy:%s:%s", libtest_arg2, hostip);
+ curl_msnprintf(proxy2_resolve, sizeof(proxy2_resolve),
+ "secondproxy:%s:%s", libtest_arg2, hostip);
+
+ /* we connect to the fake host name but the right port number */
+ curl_msnprintf(proxy1_connect, sizeof(proxy1_connect),
+ "firstproxy:%s", libtest_arg2);
+ curl_msnprintf(proxy2_connect, sizeof(proxy2_connect),
+ "secondproxy:%s", libtest_arg2);
+
+ res_global_init(CURL_GLOBAL_ALL);
+ if(result)
+ return result;
+
+ curl = curl_easy_init();
+ if(!curl) {
+ curl_mfprintf(stderr, "curl_easy_init() failed\n");
+ curl_global_cleanup();
+ return TEST_ERR_MAJOR_BAD;
+ }
+
+ host = curl_slist_append(NULL, proxy1_resolve);
+ if(!host)
+ goto test_cleanup;
+ host2 = curl_slist_append(host, proxy2_resolve);
+ if(!host2)
+ goto test_cleanup;
+ host = host2;
+
+ start_test_timing();
+
+ easy_setopt(curl, CURLOPT_RESOLVE, host);
+ easy_setopt(curl, CURLOPT_PROXYUSERPWD, "victim:secret");
+
+ curl_mprintf("--- First get over %s\n", proxy1_connect);
+ result = run1648(curl, GET_THIS, proxy1_connect);
+ if(result)
+ goto test_cleanup;
+
+ easy_setopt(curl, CURLOPT_PROXYUSERPWD, NULL);
+
+ curl_mprintf("--- Then over '%s'\n", proxy2_connect);
+ result = run1648(curl, GET_THIS, proxy2_connect);
+
+test_cleanup:
+
+ /* proper cleanup sequence - type PB */
+
+ curl_easy_cleanup(curl);
+ curl_global_cleanup();
+ curl_slist_free_all(host);
+ return result;
+}