[PATCH 4/4] proxy_pass: more tests for giant headers and truncations

[Eric Wong <e@80x24.org>]

We need to ensure more uncommon cases such as gigantic upstream
headers and truncated upstream responses are handled properly
and predictably.
---
 lib/yahns/proxy_http_response.rb |  9 ++++--
 test/test_proxy_pass.rb          | 62 ++++++++++++++++++++++++++++++++++++++--
 2 files changed, 66 insertions(+), 5 deletions(-)

diff --git a/lib/yahns/proxy_http_response.rb b/lib/yahns/proxy_http_response.rb
index 31505d3..8f4790e 100644
--- a/lib/yahns/proxy_http_response.rb
+++ b/lib/yahns/proxy_http_response.rb
@@ -28,10 +28,13 @@ def proxy_write(wbuf, buf, alive)
 
   def proxy_err_response(code, req_res, exc, wbuf)
     logger = @hs.env['rack.logger']
-    if exc
-      Yahns::Log.exception(logger, 'upstream error', exc)
-    else
+    case exc
+    when nil
       logger.error('premature upstream EOF')
+    when Kcar::ParserError
+      logger.error("upstream response error: #{exc.message}")
+    else
+      Yahns::Log.exception(logger, 'upstream error', exc)
     end
     # try to write something, but don't care if we fail
     Integer === code and
diff --git a/test/test_proxy_pass.rb b/test/test_proxy_pass.rb
index 163a0f7..47fc231 100644
--- a/test/test_proxy_pass.rb
+++ b/test/test_proxy_pass.rb
@@ -13,6 +13,11 @@ class TestProxyPass < Testcase
   TRUNCATE_HEAD = "HTTP/1.1 200 OK\r\n" \
                   "Content-Length: 666\r\n".freeze
 
+  # not too big, or kcar will reject
+  BIG_HEADER = [%w(Content-Type text/plain), %W(Content-Length #{OMFG.size})]
+  3000.times { |i| BIG_HEADER << %W(X-#{i} BIG-HEADER!!!!!!!!!!!!!!) }
+  BIG_HEADER.freeze
+
   class ProxiedApp
     def call(env)
       h = [ %w(Content-Length 3), %w(Content-Type text/plain) ]
@@ -22,6 +27,11 @@ def call(env)
         when '/giant-body'
           h = [ %W(Content-Length #{OMFG.size}), %w(Content-Type text/plain) ]
           [ 200, h, [ OMFG ] ]
+        when '/big-headers'
+          [ 200, BIG_HEADER, [ OMFG ] ]
+        when '/oversize-headers'
+          100000.times { |x| h << %W(X-TOOBIG-#{x} #{x}) }
+          [ 200, h, [ "big" ] ]
         when %r{\A/slow-headers-(\d+(?:\.\d+)?)\z}
           delay = $1.to_f
           io = env['rack.hijack'].call
@@ -61,7 +71,12 @@ def chunky.each
           [ 200, h, [ "hi\n"] ]
         end
       when 'HEAD'
-        [ 200, h, [] ]
+        case env['PATH_INFO']
+        when '/big-headers'
+          [ 200, BIG_HEADER, [] ]
+        else
+          [ 200, h, [] ]
+        end
       when 'PUT'
         buf = env['rack.input'].read
         [ 201, {
@@ -158,7 +173,7 @@ def test_proxy_pass
       @srv2.close
       cfg.instance_eval do
         app(:rack, Yahns::ProxyPass.new("http://#{host2}:#{port2}")) do
-          listen "#{host}:#{port}"
+          listen "#{host}:#{port}", sndbuf: 16384
           client_max_body_size nil
         end
         stderr_path err.path
@@ -245,6 +260,14 @@ def test_proxy_pass
       res = http.request(req)
       assert_equal OMFG, res.body
       assert_equal 201, res.code.to_i
+
+      # sometimes upstream feeds kcar too much
+      req = Net::HTTP::Get.new('/oversize-headers')
+      res = http.request(req)
+      errs = File.readlines(@err.path).grep(/ERROR/)
+      assert_equal 1, errs.size
+      assert_match %r{upstream response error:}, errs[0]
+      @err.truncate(0)
     end
 
     # ensure we do not chunk responses back to an HTTP/1.0 client even if
@@ -264,6 +287,8 @@ def test_proxy_pass
       end
     end
     check_truncated_upstream(host, port)
+    check_slow_giant_body(host, port)
+    check_slow_read_headers(host, port)
   ensure
     gplv3.close if gplv3
     quit_wait pid
@@ -376,4 +401,37 @@ def check_truncated_upstream(host, port)
       @err.truncate(0)
     end
   end
+
+  def check_slow_giant_body(host, port)
+    s = TCPSocket.new(host, port)
+    s.write "GET /giant-body HTTP/1.0\r\n\r\n"
+    sleep 0.1
+    str = ''
+    buf = ''
+    assert_raises(EOFError) { loop { str << s.readpartial(400, buf) } }
+    h, b = str.split(/\r\n\r\n/, 2)
+    assert_equal OMFG, b
+    assert_match %r{\AHTTP/1\.1 200\b}, h
+  ensure
+    s.close if s
+  end
+
+  def check_slow_read_headers(host, port)
+    s = TCPSocket.new(host, port)
+    s.write "GET /big-headers HTTP/1.1\r\nHost: example.com\r\n\r\n"
+    s.write "HEAD /big-headers HTTP/1.0\r\n\r\n"
+    buf = ''
+    res = ''
+    sleep 0.1
+    begin
+      res << s.readpartial(32786, buf)
+    rescue EOFError
+      break
+    end while true
+    # res = Timeout.timeout(60) { s.read }
+    assert_match %r{\r\n\r\n\z}, res
+    assert_match %r{\AHTTP/1\.1 200 OK}, res
+  ensure
+    s.close if s
+  end
 end
-- 
EW