QA/webconnectivity: EOF in the redirect chain (#849)

Part of #810

Strictly speaking we don't need a redirect chain to perform
this measurement but we have been hiding the initial request
from TCP/IP errors, so let's keep using that pattern.

QA/webconnectivity.py

@@ -300,6 +300,40 @@ def webconnectivity_http_nxdomain_with_consistent_dns(ooni_exe, outfile):
     assert tk["accessible"] == False
 
 
+def webconnectivity_http_eof_error_with_consistent_dns(ooni_exe, outfile):
+    """ Test case where there's a redirection and the redirected request cannot
+        continue because an eof_error error occurs. """
+    # We use a bit.ly link redirecting to nexa.polito.it. We block the HTTP request
+    # for nexa.polito.it using the cleartext bad proxy. So the error should happen in
+    # the redirect chain and should be EOF.
+    args = [
+        "-iptables-hijack-dns-to",
+        "127.0.0.1:53",
+        "-dns-proxy-hijack",
+        "nexa.polito.it",
+        "-iptables-hijack-http-to",
+        "127.0.0.1:7117",  # this is badproxy's cleartext endpoint
+    ]
+    tk = execute_jafar_and_return_validated_test_keys(
+        ooni_exe,
+        outfile,
+        "-i https://bit.ly/3h9EJR3 web_connectivity",  # bit.ly uses https
+        "webconnectivity_http_eof_error_with_consistent_dns",
+        args,
+    )
+    assert tk["dns_experiment_failure"] == None
+    assert tk["dns_consistency"] == "consistent"
+    assert tk["control_failure"] == None
+    assert tk["http_experiment_failure"] == "eof_error"
+    assert tk["body_length_match"] == None
+    assert tk["body_proportion"] == 0
+    assert tk["status_code_match"] == None
+    assert tk["headers_match"] == None
+    assert tk["title_match"] == None
+    assert tk["blocking"] == "http-failure"
+    assert tk["accessible"] == False
+
+
 def main():
     if len(sys.argv) != 2:
         sys.exit("usage: %s /path/to/ooniprobelegacy-like/binary" % sys.argv[0])
@@ -315,6 +349,7 @@ def main():
         webconnectivity_http_connection_refused_with_consistent_dns,
         webconnectivity_http_connection_reset_with_consistent_dns,
         webconnectivity_http_nxdomain_with_consistent_dns,
+        webconnectivity_http_eof_error_with_consistent_dns,
     ]
     for test in tests:
         test(ooni_exe, outfile)